JP7589601B2 - Flush water tank device and flush toilet device equipped with same - Google Patents

Description

The present invention relates to a flush water tank device, and in particular to a flush water tank device that supplies flush water to a flush toilet, and a flush toilet device equipped with the same.

JP 2009-257061 A (Patent Document 1) describes a low tank device. In this low tank device, a hydraulic cylinder device having a piston and a water draining section is placed inside a low tank equipped with a drain valve, and the piston and the drain valve are connected by a connecting section. When flushing water is to be discharged from the low tank, the solenoid valve is opened to supply water to the hydraulic cylinder device and push up the piston. Since the piston is connected to the drain valve by the connecting section, the movement of the piston pulls up the drain valve, opening the drain valve and discharging the flushing water from the low tank. The water supplied to the hydraulic cylinder device flows out from the water draining section and flows into the low tank.

Furthermore, when closing the drain valve, the solenoid valve is closed to stop the supply of water to the hydraulic cylinder device. This causes the piston that was pushed up to descend, and the drain valve returns to its closed position under its own weight. At this time, the water in the hydraulic cylinder device gradually flows out from the water drain section, so the piston descends slowly and the drain valve also slowly returns to its closed position.

JP 2009-257061 A

However, in the low tank device described in Patent Document 1, it takes a long time for the piston of the hydraulic cylinder device to return to its original position, and there is a problem in that it takes a long time after one toilet flush before the next toilet flush is possible. That is, in the low tank device described in Patent Document 1, water flows into the cylinder of the hydraulic cylinder device, pushing up the piston and raising the drain valve. After the drain valve is raised, the water that flowed into the cylinder flows out from the gap (water drainage section) between the rod section attached to the piston and the through hole provided in the cylinder, and the piston lowers and returns to its original position. Because the gap between the rod section and the through hole is narrow, it takes a relatively long time for the water in the cylinder to be discharged. Furthermore, if this gap is made larger, the pressure in the cylinder is less likely to increase, making it difficult to push up the piston during toilet flushing, so the gap cannot simply be set large.

Patent Document 1 also describes a low-tank device that drains water from within a cylinder by connecting a drain pipe to the cylinder of a hydraulic cylinder device and providing a drain pipe solenoid valve on the drain pipe. With this low-tank device, the water in the cylinder can be quickly drained through the drain pipe by opening the drain pipe solenoid valve after the drain valve is pulled up. However, this type of low-tank device requires a dedicated solenoid valve to drain the water from the cylinder, which complicates the device structure and increases the size of the hydraulic cylinder device.

Therefore, the objective of the present invention is to provide a flush water tank device that uses supplied water pressure to open the drain valve while quickly draining the water from the water pressure cylinder device (water pressure drive for the drain valve) using a simple mechanism, and to quickly return to a state where the next toilet flush can be performed, and a flush toilet device equipped with the same.

In order to solve the above-mentioned problems, the present invention provides a flush water tank device that supplies flush water to a flush toilet, comprising a water storage tank that stores flush water to be supplied to the flush toilet and has a drain port formed therein for discharging the stored flush water to the flush toilet, a drain valve that opens and closes the drain port to start and stop the supply of flush water to the flush toilet, a drain valve hydraulic drive unit that uses the water supply pressure of the supplied water to drive the drain valve, and a drain/vacuum breaker valve device that is provided upstream of the drain valve hydraulic drive unit and supplies water supplied from the upstream side to the downstream drain valve hydraulic drive unit, the drain valve hydraulic drive unit having a cylinder into which water supplied through the drain/vacuum breaker valve device flows, and a piston that is slidably disposed within the cylinder and is moved by the pressure of the water that has flowed into the cylinder to move the drain valve, and the drain/vacuum breaker valve device is characterized in that it is provided with a valve body that operates to open the upstream side to the atmosphere when the supply of water from the upstream side is stopped, and at the same time drain water that has flowed back from the drain valve hydraulic drive unit.

In the present invention thus configured, the drain valve hydraulic drive unit uses the water supply pressure of the supplied water to drive the drain valve, opening the drain outlet of the water tank, and the stored flush water is discharged into the flush toilet. A drain/vacuum breaker valve device is provided upstream of the drain valve hydraulic drive unit, and this drain/vacuum breaker valve device supplies water supplied from the upstream side to the downstream drain valve hydraulic drive unit. The drain valve hydraulic drive unit has a cylinder and a piston, and when water supplied through the drain/vacuum breaker valve device flows into the cylinder, the piston slidably arranged within the cylinder is moved by the pressure of the inflowing water, moving the drain valve. When the supply of water from the upstream side is stopped, the drain/vacuum breaker valve device opens the upstream side to the atmosphere and simultaneously drains the water that has flowed back from the drain valve hydraulic drive unit.

According to the present invention configured in this way, when the water supply from the upstream side is stopped, the drain/vacuum breaker valve device drains the water that has flowed back from the drain valve hydraulic drive unit, so that the water that has flowed into the cylinder of the drain valve hydraulic drive unit can be discharged with a simple mechanism. This allows the piston to be returned to its initial position quickly, and the toilet can be restored to a state in which the next flush can be performed in a short time. Furthermore, according to the present invention configured as above, when the water supply from the upstream side is stopped, the drain/vacuum breaker valve device opens the upstream side to the atmosphere, so that if the upstream side of the drain/vacuum breaker valve device becomes negative pressure, the atmosphere is sucked in, preventing water from flowing back to the upstream side.

In the present invention, the drain/vacuum breaker valve device preferably includes an inlet for allowing the supplied water to flow in, an outlet for supplying the inflowing water to the drain valve hydraulic drive unit, and an intake/drain opening that is opened and closed by a valve body, the inlet being provided above the outlet, and the intake/drain opening being formed on a vertical or inclined surface.

According to the present invention configured in this way, since the inlet is provided above the outlet, water that has flowed back from the drain valve hydraulic drive unit to the outlet can be reliably prevented from flowing back into the inlet. In addition, since the intake/drain opening that is opened and closed by the valve body is formed on a vertical or inclined surface, water that has flowed back from the drain valve hydraulic drive unit to the outlet can be discharged from the lower part of the intake/drain opening, and at the same time, air can be sucked in from the upper part of the intake/drain opening, allowing drainage and intake to be performed simultaneously.

In the present invention, preferably, the area of the intake/drain opening of the drain/vacuum break valve device is greater than the area of the outlet of the drain/vacuum break valve device.
According to the present invention configured in this manner, the area of the air intake/drain opening is larger than the area of the outlet of the drain/vacuum breaker valve device, so that water that has flowed back from the drain valve water pressure drive unit to the outlet can be drained while also reliably drawing in atmospheric air.

In the present invention, the intake/drain opening of the drain/vacuum breaker valve device is preferably formed to be longer in the vertical direction than in the horizontal direction.
According to the present invention configured in this manner, the intake/drain opening is formed longer in the vertical direction than in the horizontal direction, so that backflowing water can be drained and atmospheric air can be drawn in reliably with a small opening area.

In the present invention, the valve body of the drain/vacuum breaker valve device is preferably provided rotatably about a predetermined central axis, and opens and closes the intake/drain opening by being rotated.
According to the present invention configured in this manner, the valve body of the drain/vacuum break valve device opens and closes the air intake/drain opening by being rotated, so that the opening and closing mechanism for the air intake/drain opening can be configured compactly and the freedom of design of the drain/vacuum break valve device can be increased.

In the present invention, the predetermined central axis about which the valve body is rotated is preferably disposed outside the vertical projection plane of the intake/drain opening.
According to the present invention configured in this manner, the central axis about which the valve body rotates is positioned outside the vertical projection plane of the intake/drain opening. Therefore, when a gasket is provided to seal between the edge of the intake/drain opening and the valve body, a crush allowance for the gasket can be reliably secured, and the intake/drain opening can be reliably closed.

In the present invention, the intake/drain opening is preferably formed so that its lower edge extends horizontally, and water that flows back from the drain valve hydraulic drive unit to the drain/vacuum breaker valve device is discharged over the lower edge into the water tank.

According to the present invention configured in this way, the lower edge of the intake/drain opening extends horizontally, and backflowing water is discharged over this lower edge into the water tank, so a large flow path area for the drainage water flowing over the lower edge can be secured, and the rise in the water level in the drain/vacuum breaker valve device can be suppressed.

In the present invention, the air intake/drain opening is preferably formed so that its upper edge extends horizontally.
According to the present invention configured in this manner, the upper edge of the intake/drain opening extends horizontally, so that even when water is being discharged from the intake/drain opening, a large flow path area can be secured for drawing in outside air through the intake/drain opening, and atmospheric air can be reliably drawn in.

In the present invention, the valve body is preferably in a standby position in which the center of gravity of the valve body is at its lowest when water is not being supplied to the drain/vacuum breaker valve device.
According to the present invention configured in this manner, when water is not supplied to the drain/vacuum breaker valve device, the valve body is in a standby position with its center of gravity at the lowest position, so that the valve body can be returned to the standby position by its own weight with a simple structure.

In the present invention, the valve body preferably includes a weight.
According to the present invention configured in this manner, the valve disc is provided with a weight, so that the gravity acting on the valve disc can be increased, and the valve disc can be reliably returned to the standby position with a simple structure.

In the present invention, the drain/vacuum break valve device preferably includes a biasing spring, which biases the valve body in a direction that opens the intake/drain opening.
According to the present invention configured in this manner, a biasing spring is provided which biases the valve body in the direction of opening the intake/drain opening, so that the intake/drain opening can be reliably opened when the supply of water to the drain/vacuum break valve device is stopped.

In the present invention, the biasing spring is preferably configured such that the increment of the biasing force relative to the increment of the deformation amount increases as the deformation amount increases.
First, when the intake/drain opening is closed, hydrostatic pressure acts on the valve body, so a large force is required to open it, whereas when the intake/drain opening is opened even slightly, hydrostatic pressure does not act on the valve body, so the valve body can be moved with a small force. According to the present invention configured as described above, the biasing spring is configured so that the increment of the biasing force relative to the increment of the deformation amount increases as the deformation amount increases, so that the biasing force in the direction of opening the valve body is the largest when the intake/drain opening is closed and the biasing spring is most deformed. Therefore, when the supply of water to the drain/vacuum breaker valve device is stopped, the valve body can be easily opened. On the other hand, in an area where the deformation amount of the biasing spring is small, the biasing force is small, so that when the supply of water to the drain/vacuum breaker valve device is started, the valve body can be easily moved to close.

In the present invention, the biasing spring is preferably configured so as not to apply a biasing force to the valve body when the intake/drain opening is open by a predetermined amount or more.
According to the present invention thus configured, when the intake/drain opening is opened to a predetermined amount or more, no biasing force acts on the valve body, so that when water supply to the drain/vacuum breaker valve device is started, the valve body can be easily moved to close. On the other hand, when the opening of the intake/drain opening is less than the predetermined amount, a biasing force acts on the valve body, so that when water supply to the drain/vacuum breaker valve device is stopped, the valve body can be easily opened.

In the present invention, it is preferable that the device further comprises a flow rate suppressing means for suppressing the flow rate of water flowing back from the drain valve water pressure drive portion to the drain/vacuum breaker valve device.
According to the present invention configured in this manner, the flow rate suppression means suppresses the flow rate of water flowing back into the drain/vacuum breaker valve device, thereby preventing a large flow rate of water from flowing back from the drain valve water pressure drive unit, filling the intake/drain opening with water and making it impossible to take in outside air.

In the present invention, preferably, the device further comprises a generator having a water wheel rotated by the flow of supplied water and a power generation unit that generates electricity by the rotation of the water wheel, and a water supply control device having an electromagnetic valve operated by the electricity generated by the generator and controlling the start and stop of water supply to the drain/vacuum breaker valve device, the drain valve hydraulic drive unit having an outer shell arranged to surround at least a part of the drain valve in a plan view, the generator is arranged above the stop water level in the water storage tank, and is arranged on the opposite side of the outer shell in the left-right direction in a plan view from the water landing position where the water drained from the drain/vacuum breaker valve device lands on the water surface in the water storage tank.

In the present invention configured in this manner, the generator is positioned above the stop water level in the water tank, and is positioned on the opposite side of the outer casing in the left-right direction in a plan view from the water landing position where the water discharged from the drain/vacuum breaker valve device lands on the water surface in the water tank. As a result, the outer casing prevents water from splashing when the water flowing out of the drain/vacuum breaker valve device lands on the water surface in the water tank, preventing the water from getting on the generator.

In the present invention, the generator is preferably disposed in a region different from the region in which the water landing position is located when the water tank is divided into three equal regions in the left-right direction in a plan view: a left region, a central region, and a right region.

In the present invention configured in this way, the generator is disposed in one of the left, center, and right regions in plan view, which is different from the region to which the water landing position belongs, so that a relatively large distance can be secured between the water landing position and the generator. This effectively prevents water flowing out of the drain/vacuum breaker valve device from landing on the water surface in the water tank and splashing onto the generator.

In the present invention, preferably, the water landing position is located in either the left or right area of the water tank in a plan view, and the generator is disposed in the other of the left or right area of the water tank in a plan view.

In the present invention configured in this manner, the landing position of the water flowing out of the drain/vacuum breaker valve device is located in either the left or right area of the water storage tank, while the generator is disposed in the other of the left or right area. This allows a relatively large distance to be secured between the landing position of the water in the water storage tank and the generator, effectively preventing the water flowing out of the drain/vacuum breaker valve device from landing on the water surface in the water storage tank and splashing onto the generator.

In the present invention, the generator is preferably disposed on the opposite side of the outer casing of the drain valve hydraulic drive unit in the fore-and-aft direction with respect to the water landing position.

In the present invention configured in this manner, the generator is positioned on the opposite side of the outer casing in the front-to-rear direction from the landing position of the water flowing out of the drain/vacuum breaker valve device, so that the outer casing can prevent the water flowing out of the drain/vacuum breaker valve device from landing at the landing position and splashing, effectively preventing the generator from becoming wet.

In the present invention, the cylinder of the drain valve hydraulic drive unit is preferably provided above the outer shell.

In the present invention configured in this manner, the cylinder of the drain valve hydraulic drive unit is provided above the outer shell, so that the water that flows out of the drain/vacuum breaker valve device lands on the water landing position and splashes can be blocked by the cylinder, making it possible to more effectively prevent the generator from becoming wet.

The present invention also provides a flush toilet device, characterized in that it has a flush water tank device of the present invention and a flush toilet that is flushed with flush water supplied from the flush water tank device.

The present invention provides a flush water tank device that uses supplied water pressure to open the drain valve, quickly drains water from the drain valve water pressure drive unit using a simple mechanism, and quickly returns the toilet to a state where it can be flushed the next time, and a flush toilet device equipped with the same.

1 is a perspective view showing an entire flush toilet apparatus equipped with a flush water tank apparatus according to a first embodiment of the present invention. 1 is a cross-sectional view showing the schematic configuration of a flush water tank assembly according to a first embodiment of the present invention. 1 is a cross-sectional view of a drain valve hydraulic drive unit and a drain valve provided in a flush water tank apparatus according to a first embodiment of the present invention, showing a state in which the piston of the drain valve hydraulic drive unit is in a lowered first position. 1 is a cross-sectional view of a drain valve hydraulic drive unit and a drain valve provided in a flush water tank apparatus according to a first embodiment of the present invention, showing a state in which the piston of the drain valve hydraulic drive unit is in a raised second position. FIG. 1 is a cross-sectional view of a drain valve water pressure drive unit and a drain valve provided in a flush water tank apparatus according to a first embodiment of the present invention, showing a state in which the drain valve is held by a drain valve float mechanism. FIG. 1 is an exploded perspective view showing components that make up a clutch mechanism in a flush water tank assembly according to a first embodiment of the present invention; FIG. 4 is a partially enlarged cross-sectional view showing the state of the clutch mechanism when the drain valve is closed in the flush water tank assembly according to the first embodiment of the present invention; FIG. 4 is a partially enlarged cross-sectional view showing the state of the clutch mechanism when disconnected, in the flush water tank apparatus according to the first embodiment of the present invention. FIG. 4 is a partially enlarged cross-sectional view showing the state of the clutch mechanism immediately before engagement in the flush water tank assembly according to the first embodiment of the present invention; FIG. 4 is a partially enlarged cross-sectional view showing the state when the clutch mechanism is engaged in the flush water tank assembly according to the first embodiment of the present invention; FIG. 1 is a perspective view of a drain/vacuum breaker valve device provided in a flush water tank apparatus according to a first embodiment of the present invention; FIG. 1 is a cross-sectional view of a drain/vacuum break valve device provided in a flush water tank apparatus according to a first embodiment of the present invention, showing a state in which water is not being supplied from the water supply control device. 1 is a cross-sectional view of a drain/vacuum break valve device provided in a flush water tank apparatus according to a first embodiment of the present invention, showing a state in which water is being supplied from a water supply control device. 4A to 4C are diagrams for explaining the forces acting on the flap valve body of the drain/vacuum breaker valve device provided in the flush water tank apparatus according to the first embodiment of the present invention in various operating conditions. 11 is a perspective view of a drain/vacuum breaker valve device provided in a flush water tank apparatus according to a second embodiment of the present invention; FIG. 11 is a cross-sectional view of a drain/vacuum breaker valve device provided in a flush water tank apparatus according to a second embodiment of the present invention, showing a state in which water is not being supplied from the water supply control device. FIG. 11 is a cross-sectional view of a drain/vacuum breaker valve device provided in a flush water tank apparatus according to a second embodiment of the present invention, showing the state in which water is being supplied from the water supply control device. FIG. 13 is a perspective view of a drain/vacuum breaker valve device provided in a flush water tank apparatus according to a third embodiment of the present invention. FIG. 13 is a perspective view showing a part of a case of a drain/vacuum breaker valve device provided in a flush water tank apparatus according to a third embodiment of the present invention, with a part cut away; FIG. 13 is a perspective view showing a part of a case of a drain/vacuum breaker valve device provided in a flush water tank apparatus according to a third embodiment of the present invention, with a part cut away; FIG. 11 is a horizontal cross-sectional view of a drain/vacuum breaker valve device provided in a flush water tank apparatus according to a third embodiment of the present invention. FIG. A front cross-sectional view showing the schematic configuration of a flush water tank assembly according to a fourth embodiment of the present invention. A plan cross-sectional view showing the schematic configuration of a flush water tank assembly according to a fourth embodiment of the present invention. FIG. 2 is a cross-sectional view showing a typical configuration of a normal negative pressure release valve.

Next, a flush water tank apparatus and a flush toilet apparatus equipped with the same according to an embodiment of the present invention will be described with reference to the accompanying drawings.
Fig. 1 is a perspective view showing an entire flush toilet apparatus equipped with a flush water tank apparatus according to a first embodiment of the present invention. Fig. 2 is a cross-sectional view showing the schematic configuration of a flush water tank apparatus according to a first embodiment of the present invention. Figs. 3 to 5 are cross-sectional views of a drain valve water pressure drive unit and a drain valve provided in a flush water tank apparatus according to a first embodiment of the present invention.

As shown in FIG. 1, the flush toilet device 1 according to the first embodiment of the present invention is composed of a flush toilet main body 2, which is a flush toilet, and a flush water tank device 4 according to the first embodiment of the present invention, which is placed on the rear of the flush toilet main body 2. The flush toilet device 1 of this embodiment is configured to flush the bowl section 2a of the flush toilet main body 2 after use by operating a remote control device 6 attached to a wall surface or by a human body detection sensor 8, which is a human body detection sensor provided on the toilet seat, detecting that the user has left the seat and then allowing a predetermined time to pass. The flush water tank device 4 according to this embodiment is configured to discharge flush water stored inside into the flush toilet main body 2 based on an instruction signal from the remote control device 6 or the human body detection sensor 8, and to flush the bowl section 2a with this flush water. Note that in this embodiment, the human body sensor 8 is provided on the toilet seat, but the present invention is not limited to this form, and it may be provided in a position that can detect the user's sitting, leaving, approaching, leaving, and hand-waving actions, and may be provided in the flush toilet main body 2 or the flush water tank device 4, for example. Furthermore, the human presence sensor 8 can be anything that can detect the user sitting down, leaving their seat, approaching, leaving, or waving their hand. For example, an infrared sensor or a microwave sensor can be used as the human presence sensor 8.

Next, as shown in Figure 2, the flush water tank device 4 has a water storage tank 10 that stores flush water to be supplied to the flush toilet body 2, a drain valve 12 for opening and closing a drain outlet 10a provided in this water storage tank 10, and a drain valve hydraulic drive unit 14 that drives this drain valve 12. Furthermore, the flush water tank device 4 has inside the water storage tank 10 a water supply control device 18 that controls the drain valve hydraulic drive unit 14 and the supply of water into the water storage tank 10, and an electromagnetic valve 20 attached to the water supply control device 18.

The water storage tank 10 is a tank configured to store flush water to be supplied to the flush toilet body 2, and a drain outlet 10a is formed at the bottom of the tank to discharge the stored flush water into the flush toilet body 2. An overflow pipe 10b is connected to the downstream side of the drain outlet 10a inside the water storage tank 10. This overflow pipe 10b rises vertically from near the drain outlet 10a and extends above the water surface of the flush water stored in the water storage tank 10. Therefore, flush water that flows in from the upper end of the overflow pipe 10b bypasses the drain outlet 10a and flows directly into the flush toilet body 2.

Furthermore, as shown in FIG. 2, a drain/vacuum breaker valve device 30 is provided in the inlet pipe 24a between the water supply control device 18 and the drain valve hydraulic drive unit 14.
When the water supply from the water supply control device 18 is stopped, the drain/vacuum breaker valve device 30 draws outside air into the inlet pipe 24a and discharges water remaining in the cylinder 14a of the drain valve hydraulic drive unit 14 and the like from the inlet pipe 24a into the water storage tank 10. The structure and operation of the drain/vacuum breaker valve device 30 will be described later.

As shown in FIG. 2, the water supply control device 18 is configured to control the water supply to the drain valve hydraulic drive unit 14 based on the operation of the solenoid valve 20, and to control the supply and stop of water to the water storage tank 10. That is, the water supply control device 18 is connected between the water supply pipe 32 connected to the water supply and the inflow pipe 24a connected to the drain valve hydraulic drive unit 14, and controls the supply and stop of water supplied from the water supply pipe 32 to the drain valve hydraulic drive unit 14 based on an instruction signal from the controller 28. In this embodiment, all of the water flowing out of the water supply control device 18 is supplied to the drain valve hydraulic drive unit 14 through the inflow pipe 24a. In addition, most of the water supplied to the drain valve hydraulic drive unit 14 flows out of the cylinder 14a through the outflow pipe 24b, and is branched at the outflow pipe branching part 24c into a part that flows into the water storage tank 10 and a part that flows into the flush toilet body 2 through the overflow pipe 10b.

Furthermore, an orifice 24d, which is a flow rate suppression means, is provided midway in the inflow pipe 24a between the drain/vacuum breaker valve device 30 and the drain valve hydraulic drive unit 14. The orifice 24d is a throttle section provided inside the inflow pipe 24a, and is configured so that the flow path cross-sectional area gradually decreases from the upstream side to the downstream side. The orifice 24d is configured to suppress the flow rate of water flowing through the inflow pipe 24a, and in particular, is configured to suppress the flow rate of water flowing back from the drain valve hydraulic drive unit 14 to the drain/vacuum breaker valve device 30.

Meanwhile, water supplied from the water mains is supplied to the water supply control device 18 via a stop valve 32a located outside the water storage tank 10 and a constant flow valve 32b located inside the water storage tank 10 downstream of this stop valve 32a. The stop valve 32a is provided to stop the supply of water to the flush water tank device 4 during maintenance, etc., and is normally used in an open state. The constant flow valve 32b is provided to allow water supplied from the water mains to flow into the water supply control device 18 at a predetermined flow rate, and is configured to supply a constant flow rate of water to the water supply control device 18 regardless of the installation environment of the flush toilet device 1.

The water supply control device 18 is also equipped with a solenoid valve 20, and the water supply from the water supply control device 18 to the drain valve water pressure drive unit 14 is controlled based on the operation of this solenoid valve 20. Specifically, the controller 28 receives signals from the remote control device 6 and the human presence sensor 8, and sends an electrical signal to the solenoid valve 20 to operate it.

Furthermore, a water supply valve float 34 is also connected to the water supply control device 18 and is configured to set the water level in the water storage tank 10 to a predetermined water stop water level _L1 . The water supply valve float 34 is disposed in the water storage tank 10 and is configured to rise together with the water level in the water storage tank 10 and to stop the water supply from the water supply control device 18 to the drain valve water pressure drive unit 14 when the water level rises to the predetermined water stop water level _L1 .

The water supply control device 18 has a main body 36 to which the water supply pipe 32 and the inlet pipe 24a are connected, a main valve body 38 disposed within the main body 36, a valve seat 40 on which the main valve body 38 sits, an arm portion 42 that is rotated by the water supply valve float 34, a float side pilot valve 44 that is moved by the rotation of the arm portion 42, and a solenoid valve side pilot valve 50.

The main body 36 is a member having a connection for the water supply pipe 32 at the bottom and a connection for the drain/vacuum breaker valve device 30 on one side, and is configured so that the solenoid valve 20 can be attached to the side opposite the drain/vacuum breaker valve device 30. A valve seat 40 is formed inside the main body 36, and this valve seat 40 is configured to communicate with the drain/vacuum breaker valve device 30. Furthermore, a main valve body 38 is arranged inside the main body 36 to open and close the valve seat 40, and is configured so that when the valve is open, tap water flowing in from the water supply pipe 32 flows through the valve seat 40 and into the drain/vacuum breaker valve device 30.

The main valve body 38 is a generally disc-shaped diaphragm-type valve body that is attached inside the main body 36 so that it can seat and unseat on the valve seat 40. A pressure chamber 36a is formed inside the main body 36 on the opposite side of the valve seat 40 from the main valve body 38. That is, the pressure chamber 36a is defined by the inner wall surface of the main body 36 and the main valve body 38, and when the pressure inside this pressure chamber 36a increases, the main valve body 38 is pressed against the valve seat 40 by this pressure and seats on the valve seat 40.

On the other hand, the solenoid valve 20 is attached to the main body 36 and is configured to be able to move the solenoid valve side pilot valve 50 back and forth. That is, the solenoid valve side pilot valve 50 is configured to open and close a pilot valve port (not shown) provided in the pressure chamber 36a. Also, the float side pilot valve 44 is configured to open and close a float side pilot valve port (not shown) provided in the pressure chamber 36a.

Meanwhile, the feed valve float 34 is supported by an arm portion 42, to which a float side pilot valve 44 is connected. When the water level in the water storage tank 10 has risen to a predetermined water stop level _L1 , the feed valve float 34 is pushed upward, and the float side pilot valve 44 closes the float side pilot valve port (not shown) of the pressure chamber 36a. Meanwhile, when flush water is drained from the water storage tank 10 and the water level in the water storage tank 10 drops, the feed valve float 34 moves downward, and the float side pilot valve 44 moves, opening the float side pilot valve port.

With this configuration, when the water level in the water tank 10 is at a predetermined stop water level _L1 and no current is applied to the solenoid valve 20, during standby for toilet flushing, the pilot valve port (not shown) of the main valve body 38 and the float side pilot valve port (not shown) of the main body 36 are both in a closed state.

Tap water supplied from the water supply pipe 32 flows into the pressure chamber 36a. When the solenoid valve side pilot valve 50 closes the pilot valve port (not shown) and the float side pilot valve 44 closes the float side pilot valve port (not shown), the pressure in the pressure chamber 36a increases due to the inflowing tap water. When the pressure in the pressure chamber 36a increases in this way, this pressure presses the main valve body 38 toward the valve seat 40, causing the main valve body 38 to close the valve seat 40.

On the other hand, when the solenoid valve 20 is energized and the solenoid valve side pilot valve 50 opens the pilot valve port (not shown), the pressure in the pressure chamber 36a drops, which causes the main valve body 38 to move away from the valve seat 40 and open the valve seat 40. When the water level in the water storage tank 10 is lower than a predetermined water stop water level _L1 , the water supply valve float 34 drops and the float side pilot valve 44 opens the float side pilot valve port (not shown). This causes the pressure in the pressure chamber 36a to drop and the valve seat 40 to open. In this way, when either the pilot valve port of the main valve body 38 or the float side pilot valve port is open, the pressure in the pressure chamber 36a drops and the valve seat 40 opens.

Next, the structure of the drain valve hydraulic drive unit and the drain valve will be described with reference to Figures 3 to 5. Figure 3 is a cross-sectional view of the drain valve hydraulic drive unit 14 and the drain valve 12, showing the state in which the piston of the drain valve hydraulic drive unit 14 is in a lowered first position. Figure 4 is a cross-sectional view of the drain valve hydraulic drive unit 14 and the drain valve 12, showing the state in which the piston of the drain valve hydraulic drive unit 14 is in a raised second position. Figure 5 is a cross-sectional view of the drain valve hydraulic drive unit 14 and the drain valve 12, showing the state in which the drain valve 12 is held by the drain valve float mechanism.

As shown in Figures 3 and 4, the drain valve 12 is a direct acting valve body arranged to open and close the drain outlet 10a, and is composed of a rod-shaped valve shaft 12a and a valve body portion 12b attached to its lower end. When the drain valve 12 is pulled up vertically, the drain outlet 10a opens and flush water in the water storage tank 10 is discharged into the flush toilet body 2, flushing the bowl portion 2a.

The drain valve hydraulic drive unit 14 is provided above the drain valve 12 and is configured to drive the drain valve 12 using the water supply pressure of the cleaning water supplied from the waterworks. Specifically, the drain valve hydraulic drive unit 14 has a cylinder 14a into which water supplied from the water supply control device 18 (Fig. 2) flows in through an inlet pipe 24a, and a piston 14b slidably arranged within the cylinder 14a. Furthermore, a rod 15, which is a drive member, is attached to the underside of the piston 14b, and this rod 15 protrudes from the lower end of the cylinder 14a and extends toward the drain valve 12 (Fig. 3). The rod 15 is also arranged so as to be positioned in the same straight line as the valve shaft 12a that rises from the center of the valve body portion 12b of the drain valve 12, and the drain valve 12 and the rod 15 are arranged coaxially.

Furthermore, a spring 14c is disposed inside the cylinder 14a, and biases the piston 14b downward. An elastic annular packing 14e is attached to the outer periphery of the piston 14b, and this packing 14e is formed with an inverted U-shaped cross section that is open on the bottom. Furthermore, the packing 14e contacts the inner wall surface of the cylinder 14a in an elastically deformed state, ensuring watertightness between the inner wall surface of the cylinder 14a and the piston 14b. A clutch mechanism 22 is provided at the connection between the lower end of the rod 15 and the drain valve 12, and this clutch mechanism 22 connects the rod 15 and the drain valve 12, and releases the connection between the rod 15 and the drain valve 12 at a predetermined timing.

The cylinder 14a is a cylindrical member, the axis of which is arranged vertically, and the piston 14b is slidably received inside. The internal space of the cylinder 14a is divided by the piston 14b into a pressure chamber 16a below the piston 14b and a back pressure chamber 16b above the piston 14b. The piston 14b is arranged in the cylinder 14a so as to be able to slide between a first position shown in FIG. 3 and a second position shown in FIG. 4. As shown in FIG. 3, in the first position where the piston 14b is located at the lowest position, the volume of the pressure chamber 16a below the piston 14b is smallest, and the volume of the back pressure chamber 16b above the piston 14b is largest. On the other hand, in the second position of the piston 14b shown in FIG. 4, the volume of the pressure chamber 16a below the piston 14b is largest, and the volume of the back pressure chamber 16b above the piston 14b is smallest.

As shown in FIG. 3, the lower end of the cylinder 14a is connected to an inlet pipe 24a, which is a water supply passage for the drive unit, and this inlet pipe 24a communicates with the pressure chamber 16a in the cylinder 14a via an inlet 25a. That is, water flowing out from the water supply control device 18 (FIG. 2) flows into the pressure chamber 16a in the cylinder 14a through the inlet 25a. The water flowing into the pressure chamber 16a increases the pressure in the pressure chamber 16a, and the piston 14b is pushed up against the biasing force of the spring 14c. That is, the piston 14b is moved from the first position to the second position by the pressure of the tap water, and the drain valve 12 is driven accordingly.

On the other hand, an outlet 25b is provided at the top of the cylinder 14a, and the outflow pipe 24b communicates with the back pressure chamber 16b in the cylinder 14a through this outlet 25b. Therefore, water that flows into the back pressure chamber 16b of the cylinder 14a flows out through the outlet 25b. Also, as shown in FIG. 2, an outflow pipe branch 24c is provided at the tip of the outflow pipe 24b extending from the cylinder 14a. The outflow pipe 24b branched at the outflow pipe branch 24c is configured so that one of the pipes flows water into the water storage tank 10 and the other flows water into the overflow pipe 10b. Therefore, part of the water that flows out of the cylinder 14a is discharged through the overflow pipe 10b into the flush toilet body 2, and the rest is stored in the water storage tank 10.

As shown in Figures 3 and 4, the rod 15 is a rod-shaped member connected to the underside of the piston 14b, and extends through a sleeve 14f formed on the bottom surface of the cylinder 14a so as to protrude downward from within the cylinder 14a. The sleeve 14f is a cylindrical part extending vertically, and is provided so as to penetrate the bottom surface of the cylinder 14a, and the rod 15 extends through the inside of the sleeve 14f. The lower end of the rod 15 is connected to the drain valve 12 via a clutch mechanism 22. Therefore, when water flows into the cylinder 14a and the piston 14b is pushed up, the rod 15 connected to the piston 14b lifts the drain valve 12 upward, and the drain valve 12 opens.

A gap 14d is provided between the rod 15 protruding from below the cylinder 14a and the inner wall surface of the sleeve 14f of the cylinder 14a, and some of the water that flows into the cylinder 14a flows out from this gap 14d. The water that flows out from the gap 14d flows into the water storage tank 10. Note that this gap has a relatively narrow cross-sectional area and a large flow resistance. Therefore, even if water flows out from the gap 14d, if the water force is strong, the pressure in the pressure chamber 16a increases due to the water flowing into the cylinder 14a from the inlet pipe 24a, and the piston 14b is pushed up against the biasing force of the spring 14c.

Furthermore, as shown in Figs. 3 and 4, a communication passage 17 is provided at the upper end of the rod 15, and this communication passage 17 extends inside the rod 15 along the central axis from the upper end of the rod 15. The communication passage 17 extends from an upper end opening 17a, which is a back pressure chamber opening provided at the upper end of the rod 15, to a side opening 17b, which is a rod opening provided at the middle part of the side of the rod 15. In this embodiment, the rod 15 is provided so as to penetrate the piston 14b, and the upper end opening 17a formed at the upper end of the rod 15 opens into the back pressure chamber 16b above the piston 14b. This upper end opening 17a opens into the back pressure chamber 16b upward, i.e., in the sliding direction of the piston 14b.

In addition, an outflow guide portion 14g is provided on the ceiling surface of the cylinder 14a so as to hang down downward. This outflow guide portion 14g is provided inside the spring 14c arranged in the cylinder 14a, and is formed in a shape in which a part of a cylinder is cut out. In addition, the cutout part of the cylinder that constitutes the outflow guide portion 14g is directed toward the outflow port 25b of the cylinder 14a. Therefore, water that flows into the back pressure chamber 16b from the upper end opening 17a through the communication flow path 17 is guided toward the outflow port 25b by the outflow guide portion 14g. In addition, as shown in FIG. 4, when the piston 14b is moved to the second position, the lower end of the outflow guide portion 14g abuts against the upper surface of the piston 14b. In other words, the piston 14b is positioned at the second position by abutting against the lower end of the outflow guide portion 14g.

In this embodiment, the upper end opening 17a formed at the upper end of the rod 15 functions as a back pressure chamber opening that opens to the back pressure chamber 16b, but the back pressure chamber opening does not necessarily have to be provided in the rod 15, and may be provided in the piston 14b. In this case, a part of the communication flow passage 17 is formed inside the piston 14b, and the communication flow passage 17 extending from the back pressure chamber opening provided on the back pressure chamber 16b side of the piston 14b is connected to the communication flow passage 17 provided inside the rod 15.

On the other hand, the side opening 17b, which is a rod opening, is located at the lower end of the communication flow passage 17 and opens to the side of the middle part of the rod 15. In addition, in this embodiment, two side openings 17b are provided at the same height on both sides of the center line of the rod 15. Preferably, when multiple side openings 17b are provided, they are provided at the same height in symmetrical positions with respect to the central axis of the rod. That is, in this embodiment, the two side openings 17b are provided at a central angle of 180 degrees around the central axis of the rod, but for example, when three side openings 17b are provided, each side opening 17b is preferably provided at a central angle of 120 degrees, and when four side openings are provided, each side opening 17b is preferably provided at a central angle of 90 degrees.

3, when the piston 14b is in the first position, each side opening 17b provided on the rod 15 is located outside the pressure chamber 16a, i.e., outside the cylinder 14a. That is, when the piston 14b is in the first position where it is lowered, each side opening 17b provided on the side of the rod 15 is located below the lower end of the sleeve 14f, and each side opening 17b opens to the outside of the cylinder 14a. In this state, the back pressure chamber 16b above the piston 14b is communicated with the outside of the cylinder 14a via the communication flow passage 17. Note that when the piston 14b is in the first position, each side opening 17b of the rod 15 is located below the water stop water level L1 shown by the dashed line in FIG. ₃ , and the side opening 17b is submerged.

On the other hand, as shown in FIG. 4, when the piston 14b is in the second position, each side opening 17b on the rod 15 is located inside the pressure chamber 16a. That is, when the piston 14b is raised to the second position, each side opening 17b on the side of the rod 15 is located above the upper end of the sleeve 14f, and each side opening 17b opens to the inside of the pressure chamber 16a in the cylinder 14a. In this state, the back pressure chamber 16b above the piston 14b and the pressure chamber 16a below the piston 14b are connected via the communication flow path 17.

Also, as shown in FIG. 5, the edge 17c of each side opening 17b on the piston 14b side is formed to extend linearly in a direction perpendicular to the central axis of the rod 15 (horizontal direction in FIG. 5). Here, when the piston 14b approaches the second position and the upper edge 17c of the side opening 17b reaches above the upper end of the sleeve 14f, each side opening 17b begins to open into the pressure chamber 16a. At this time, since the edge 17c is formed to extend perpendicular to the central axis of the rod 15, when the upper edge 17c reaches slightly above the upper end of the linearly formed sleeve 14f, the area of each side opening 17b opening into the pressure chamber 16a suddenly becomes wider. For this reason, the water in the pressure chamber 16a flows rapidly into the communication flow passage 17 through each side opening 17b. This allows the water pressure in the pressure chamber 16a to be rapidly reduced, preventing the pressure in the pressure chamber 16a and the pressure in the back pressure chamber 16b from reaching equilibrium while the piston 14b is moving, preventing the piston 14b from becoming stuck.

Next, the clutch mechanism 22 is provided between the rod 15 and the valve shaft 12a of the drain valve 12. The clutch mechanism 22 is configured to separate the valve shaft 12a of the drain valve 12 from the rod 15 when the drain valve 12 is lifted to a predetermined position. When the clutch mechanism 22 is in a disconnected state, the drain valve 12 is no longer linked to the movement of the piston 14b and the rod 15, and descends due to gravity while resisting buoyancy. Details of the clutch mechanism 22 will be described later.

On the other hand, as shown in FIG. 5, a float mechanism, a drain valve float mechanism 26, is provided near the valve shaft 12a of the drain valve 12. Note that FIG. 5 is a cross-sectional view showing the state in which the drain valve 12 is held by the drain valve float mechanism 26, and the cutting direction of the cross section is rotated 90 degrees from FIG. 3 and FIG. 4. The drain valve float mechanism 26 is configured to delay the drain valve 12 descending and closing the drain port 10a after the rod 15 is lifted a predetermined distance and the drain valve 12 is separated by the clutch mechanism 22. Specifically, the drain valve float mechanism 26 has a float portion 26a, which is a float, an engagement portion 26b interlocked with the float portion 26a, and a float shaft 26c that connects the float portion 26a and the engagement portion 26b.

On the other hand, an engagement protrusion 12c is provided on the valve shaft 12a of the drain valve 12, and when the drain valve 12 is lifted up, the engagement protrusion 12c is located above the engagement portion 26b of the drain valve float mechanism 26. When the lifted drain valve 12 is separated by the clutch mechanism 22, the engagement protrusion 12c of the descending drain valve 12 engages with the engagement portion 26b, preventing the drain valve 12 from descending (FIG. 5 shows the state in which the engagement portion 26b and the engagement protrusion 12c are engaged and the drain valve 12 is held). Next, the float portion 26a descends as the water level in the water storage tank 10 drops, and when the water level in the water storage tank 10 drops to a predetermined water level, the float portion 26a rotates the engagement portion 26b to the release position shown by the imaginary line in FIG. 5. When the engagement portion 26b is rotated to the release position, the engagement between the engagement portion 26b and the engagement protrusion 12c is released. When the engagement is released, the drain valve 12 descends and seats on the drain outlet 10a. This delays the closing of the drain valve 12, allowing the appropriate amount of flush water to be discharged from the drain outlet 10a.

Next, with additional reference to FIGS. 6 to 10, the clutch mechanism 22 that connects the drain valve 12 and the rod 15 will be described.
Fig. 6 is an exploded perspective view showing the components constituting the clutch mechanism 22. Fig. 7 is a partially enlarged cross-sectional view showing the state of the clutch mechanism 22 when the drain valve 12 is closed. Fig. 8 is a partially enlarged cross-sectional view showing the state of the clutch mechanism 22 when it is released from engagement. Fig. 9 is a partially enlarged cross-sectional view showing the state of the clutch mechanism 22 just before engagement. Fig. 10 is a partially enlarged cross-sectional view showing the state when the clutch mechanism 22 is engaged.

First, as shown in FIG. 6, the clutch mechanism 22 is composed of the lower end of the rod 15, the upper end of the valve shaft 12a of the drain valve 12, and a movable member 60 attached to this upper end. That is, the rod 15 extends downward from the underside of the piston 14b of the drain valve hydraulic drive unit 14, and the lower end of this rod 15 forms part of the clutch mechanism 22. In addition, a movable member 60 is rotatably attached to the upper end of the valve shaft 12a, and the movable member 60 engages/disengages with the lower end of the rod 15, thereby connecting/disconnecting the rod 15 and the drain valve 12.

The lower end of the rod 15 is formed with a thin-walled portion 15a and a lifting portion 15b, which function as part of the clutch mechanism 22. On the other hand, a support portion 12d is provided at the upper end of the valve shaft 12a of the drain valve 12. This support portion 12d is composed of a pair of bearings formed so that the sides are open, and both ends of the movable member 60 are rotatably attached to it.

The thin-walled portion 15a at the lower end of the rod 15 is thinner than the upper portion of the rod 15. The lifting portion 15b of the rod 15 is formed to protrude horizontally on both sides from the lower end of the thin-walled portion 15a, and when the drain valve 12 is lifted, the lifting portion 15b of the rod 15 engages with the movable member 60.

The movable member 60 has a base plate 62 extending laterally, a pair of rotation shafts 66 extending outward from both ends of the base plate 62, a pair of arms 64 rising vertically from both ends of the base plate 62, and abutment portions 68 extending inward from the upper ends of each arm 64. Each rotation shaft 66 of the movable member 60 is received by each support portion 12d provided at the upper end of the valve shaft 12a, and the movable member 60 is supported so that it can rotate.

The base plate 62 is a plate-like portion that extends laterally and is formed in a T-shape when viewed from above. The arms 64 are formed to rise upward from both ends of the T-shaped base plate 62. When the clutch mechanism 22 is connected, the thin-walled portion 15a and the lifting portion 15b at the lower end of the rod 15 are located between the pair of arms 64. The rotating shafts 66 are formed to protrude horizontally from both the left and right ends of the base plate 62 and from the base ends of each arm 64, and are received by each support portion 12d of the valve shaft 12a.

The abutment portions 68 are formed to protrude inward from the upper end of each arm 64. When viewed from a direction parallel to the rotation shaft 66, the abutment portions 68 have a teardrop-shaped cross section, and the lower side is formed into an arc-shaped curved surface. When the clutch mechanism 22 is engaged, the thin-walled portion 15a at the lower end of the rod 15 is located between the abutment portions 68, and both ends of the lifting portion 15b are located below the abutment portions 68.

Next, the operation of the clutch mechanism 22 will be described with reference to FIGS.
First, when the drain valve 12 is seated on the drain port 10a and the clutch mechanism 22 is connected, the movable member 60 is in the "engaged position" shown in Fig. 7. When the movable member 60 is in the engaged position, the lifting portion 15b at the lower end of the rod 15 is located directly below the abutment portion 68 of the movable member 60. When flushing water is supplied to the drain valve hydraulic drive unit 14 (Fig. 2) and the rod 15 is pulled upward from the state shown in Fig. 7, the rod 15 pulls the drain valve 12 vertically upward. That is, when the rod 15 is pulled up, the upper surface 15c of the lifting portion 15b of the rod 15 engages with the lower end of the abutment portion 68 of the movable member 60 while the movable member 60 maintains the engaged position, and the drain valve 12 is pulled up.

In addition, when the drain valve 12 is pulled up together with the rod 15 with the clutch mechanism 22 connected, the movable member 60 approaches the bottom surface of the cylinder 14a of the drain valve hydraulic drive unit 14. Then, when the drain valve 12 is pulled up to a predetermined position, as shown in FIG. 8, the tip of the regulating portion 70 protruding downward from the bottom surface of the cylinder 14a abuts against the base plate 62 of the movable member 60. When the base plate 62 abuts against the tip of the regulating portion 70, the movable member 60 is rotated about the rotation shaft 66 from the "engaged position" shown in FIG. 7 to the "disengaged position" shown in FIG. 8. When the movable member 60 is rotated to the "disengaged position", the engagement between the lifting portion 15b of the rod 15 and the abutting portion 68 of the movable member 60 is released, and the clutch mechanism 22 is released. That is, when the movable member 60 is rotated around the rotation axis 66, the abutment portion 68 provided at the tip of the arm 64 moves and disengages from the lifting portion 15b at the lower end of the rod 15, and the engagement between the abutment portion 68 and the lifting portion 15b is released.

When the clutch mechanism 22 is released, the drain valve 12 is separated from the rod 15 and the drain valve 12 descends and seats on the drain port 10a. This stops the discharge of flush water from the water storage tank 10 to the flush toilet body 2.
Next, when the supply of flush water to the drain valve hydraulic drive unit 14 is stopped, the piston 14b and rod 15 are lowered by the biasing force of the spring 14c arranged inside the cylinder 14a. As shown in Fig. 9, as the rod 15 is lowered, the lower end of the rod 15 approaches the movable member 60 attached to the drain valve 12 seated in the drain port 10a. Note that since the center of gravity of the movable member 60 is located to the left of the center of the rotation shaft 66 in Fig. 9, the movable member 60 maintains the "disengaged position" even after the clutch mechanism 22 is released in Fig. 7.

When the rod 15 is further lowered, as shown in FIG. 10, the abutment portion 15d of the rod 15 abuts against the base plate 62 of the movable member 60, and the movable member 60 is rotated clockwise in FIG. 10. As a result, the movable member 60, which was in the "disengaged position", is rotated to the "engaged position" shown in FIG. 7 and returns to the state shown in FIG. 7, and the clutch mechanism 22 is connected.

11 to 13, the drain/vacuum breaker valve assembly 30 connected between the water supply control device 18 and the drain valve hydraulic actuator 14 will now be described.
Fig. 11 is a perspective view of the drain/vacuum breaker valve device 30. Fig. 12 is a cross-sectional view of the drain/vacuum breaker valve device 30 in a state in which water is not being supplied from the water supply control device 18, and Fig. 13 is a cross-sectional view of the drain/vacuum breaker valve device 30 in a state in which water is being supplied.

As shown in FIGS. 12 and 13, the drain/vacuum breaker valve device 30 has a valve body case 72, a flap valve body 80 which is a valve body, and a packing 82.
As shown in Figure 11, the valve body case 72 is composed of a box-shaped main body 74, an inlet pipe connecting member 76 attached to the upper surface of the main body 74, and an outlet pipe connecting member 78 attached to the lower side of the main body 74.

The main body 74 of the valve body case 72 is configured in the shape of a roughly rectangular box with one lower corner cut out. The top surface of the main body 74 is open, and an inlet pipe connecting member 76 is attached to close this opening 74a. In addition, an attachment portion 74b for an outlet pipe connecting member 78 is provided on the lower side surface of the main body 74 that is not cut out, and the outlet pipe connecting member 78 is attached thereto. Furthermore, an intake/drain opening 74c is provided on the side surface of the main body 74, above the attachment portion 74b.

The intake/drain opening 74c is a vertically elongated rectangular opening oriented in a generally vertical direction. When the flap valve body 80 is open, outside air is sucked in through the intake/drain opening 74c, and water that has flowed back from the inlet pipe 24a flows out and is discharged into the water storage tank 10. That is, the intake/drain opening 74c is formed on a vertical surface oriented in a generally vertical direction of the main body 74, and is formed to be longer in the vertical direction than in the horizontal direction. In addition, the upper edge 74d and the lower edge 74e of the intake/drain opening 74c are each formed in a straight line extending in the horizontal direction, and water that has flowed back into the drain/vacuum breaker valve device 30 is discharged into the water storage tank 10 beyond the lower edge 74e. The intake/drain opening 74c may be provided on an inclined surface that is inclined with respect to the horizontal direction.

The inlet pipe connection member 76 is provided with a water pipe attachment portion 76a that protrudes upward, and a water pipe extending from the water supply control device 18 (Figure 2) is connected to this water pipe attachment portion 76a. The lower end of the water pipe attachment portion 76a opens into the inside of the main body portion 74, and water supplied from the water supply control device 18 flows into the drain/vacuum breaker valve device 30 through the inlet 76c at the lower end of the water pipe attachment portion 76a. In other words, water flowing out from the water supply control device 18 flows vertically downward from the inlet 76c into the valve body case 72 through the water pipe attachment portion 76a provided at the top of the drain/vacuum breaker valve device 30.

The outlet pipe connection member 78 is provided with a water pipe attachment 78a that protrudes horizontally, and the inlet pipe 24a is connected to the water pipe attachment 78a. Therefore, water supplied from the water supply control device 18 and flowing into the valve body case 72 flows out of the drain/vacuum breaker valve device 30 through the outlet 78b at the upstream end of the water pipe attachment 78a, and is supplied to the drain valve hydraulic drive unit 14 via the inlet pipe 24a. In other words, the water that flows into the drain/vacuum breaker valve device 30 is supplied to the drain valve hydraulic drive unit 14 through the outlet 78b. The area of the intake/drain opening 74c is formed larger than the area of the outlet 78b, and the inlet 76c is provided above the outlet 78b.

The flap valve body 80 is a generally L-shaped member rotatably attached inside the valve body case 72, and is configured to open and close the intake/drain opening 74c. In addition, a support shaft 80a, which is a central axis extending horizontally, is formed near the corner of the L-shaped flap valve body 80. This support shaft 80a is rotatably supported by a bearing portion 76b provided on the inlet pipe connection member 76, and the flap valve body 80 is rotated between the state shown in FIG. 12 and the state shown in FIG. 13. The support shaft 80a is located outside the vertical projection plane of the intake/drain opening 74c. In other words, the support shaft 80a is located outside the projection plane of the intake/drain opening 74c formed by shining light perpendicularly to the surface (vertical surface) on which the intake/drain opening 74c is formed.

The flap valve body 80 also has an arm portion extending laterally, and a supply water receiver 80b is provided at the tip of this arm portion. The supply water receiver 80b is disposed below the water pipe attachment portion 76a so as to cover the inlet 76c. Therefore, when water flows in through the inlet 76c, the supply water receiver 80b of the flap valve body 80 is pushed downward, and the flap valve body 80 is rotated from the state shown in FIG. 12 to the state shown in FIG. 13.

Furthermore, the flap valve body 80 has a valve plate portion 80c extending downward from the support shaft 80a, and a drainage receiving portion 80d provided on the lower side of the valve plate portion 80c. The valve plate portion 80c is arranged to face the intake/drain opening 74c provided on the side of the main body portion 74, and is configured to cover the intake/drain opening 74c when the flap valve body 80 is rotated to the state shown in Figure 13. In addition, a thin plate-shaped packing 82 is attached to the surface of the valve plate portion 80c facing the intake/drain opening 74c, and when the flap valve body 80 is rotated to the state shown in Figure 13, the gap between the valve plate portion 80c and the intake/drain opening 74c is sealed. Here, the support shaft 80a of the flap valve body 80 is positioned outside the vertical projection plane of the intake/drain opening 74c, so that the crushing allowance of the packing 82 can be reliably secured when the flap valve body 80 is rotated to the state shown in FIG. 13.

The drain receiver 80d is formed on the underside of the valve plate portion 80c and is positioned to face the outlet port 78b of the outlet pipe connection member 78. Therefore, when water flows back from the inlet pipe 24a to the water pipe attachment portion 78a, the drain receiver 80d is pushed and rotated from the state shown in FIG. 13 to the state shown in FIG. 12. The water that flows back from the water pipe attachment portion 78a flows out through the intake/drain opening 74c and is discharged into the water storage tank 10.

Furthermore, the valve plate portion 80c is provided with a weight attachment portion 80e so as to protrude from the intake/drain opening 74c, and a weight 82a is attached to the tip of this weight attachment portion 80e. By attaching this weight 82a, the center of gravity of the entire flap valve body 80 is located on the side closer to the intake/drain opening 74c than the support shaft 80a (the right side in Figures 12 and 13). As a result, a moment of force acts to rotate the flap valve body 80 clockwise in Figure 13 around the support shaft 80a, and in a standby state where the static pressure and dynamic pressure of water are not acting, the flap valve body 80 is rotated to the position shown in Figure 12. In other words, when water is not supplied to the drain/vacuum breaker valve device 30, the flap valve body 80 is in the standby position shown in Figure 12, where the center of gravity of the flap valve body 80 is at its lowest position.

In addition, a coil spring 84, which is a biasing spring, is attached to the bottom surface of the cutout portion of the main body 74 facing vertically upward. The upper end of this coil spring 84 is located below the supply water receiving portion 80b of the flap valve body 80. As shown in FIG. 13, when the intake/drain opening 74c is closed by the valve plate portion 80c, the upper end of the coil spring 84 abuts against the supply water receiving portion 80b, and the flap valve body 80 is biased in a direction to rotate clockwise. That is, the coil spring 84 biases the flap valve body 80 in a direction to open the intake/drain opening 74c. On the other hand, when the flap valve body 80 is rotated to the position shown in FIG. 12, the upper end of the coil spring 84 does not abut against the supply water receiving portion 80b, and the biasing force of the coil spring 84 does not act. In this way, the coil spring 84 does not exert a biasing force on the flap valve body 80 when the intake/drain opening 74c is open to a predetermined amount or more.

In this embodiment, a cylindrical biasing spring is used as the coil spring 84, and the increment of the biasing force relative to the increment of the deformation amount is almost constant. In contrast, as a modified example, a conical coil spring can be used as the biasing spring. A conical coil spring has a characteristic that the increment of the biasing force relative to the increment of the deformation amount increases as the deformation amount increases. Therefore, even if a conical coil spring is arranged to constantly bias the flap valve body 80, a biasing force similar to that of this embodiment can be applied. In other words, by using a conical coil spring, a biasing force can be applied so that the biasing force is relatively small when the flap valve body 80 is in an open state, and the biasing force becomes suddenly stronger as the flap valve body 80 approaches the closed position.

Next, the operation of the flush water tank apparatus 4 according to the first embodiment of the present invention and the flush toilet apparatus 1 equipped with it will be described.
First, in the toilet flush standby state, the water level in the water storage tank 10 is at a predetermined water level _L1 , and no current is being applied to the solenoid valve 20. In this state, the solenoid valve side pilot valve 50 and the float side pilot valve 44 (FIG. 2) of the water supply control device 18 are both in a closed state, and the valve seat 40 is closed by the main valve body 38. Next, when the user presses the flush button on the remote control device 6 (FIG. 1), the remote control device 6 transmits a toilet flush command signal to the controller 28 (FIG. 2). Note that in the flush toilet device 1 of this embodiment, a toilet flush command signal is also transmitted to the controller 28 if a predetermined time has passed without the flush button on the remote control device 6 being pressed after the human presence sensor 8 (FIG. 1) detects that the user has left the seat.

When a toilet flush command signal is received, the controller 28 energizes the solenoid valve 20 and opens the solenoid valve pilot valve 50. This reduces the pressure in the pressure chamber 36a, causing the main valve body 38 to move away from the valve seat 40 and open the valve seat 40. As a result, tap water supplied from the water supply pipe 32 to the water supply control device 18 (Figure 2) flows out of the water supply control device 18 and into the drain/vacuum breaker valve device 30.

When water flows into the drain/vacuum breaker valve device 30, as shown in FIG. 13, the supply water receiver 80b of the flap valve body 80 is pushed downward, and the flap valve body 80 is rotated to the position shown in FIG. 13. This causes the intake/drain opening 74c of the drain/vacuum breaker valve device 30 to be blocked by the flap valve body 80. Water that flows in from the inlet 76c of the drain/vacuum breaker valve device 30 bypasses the supply water receiver 80b and flows into the valve body case 72, as shown by the arrow in FIG. 13, and then bypasses the drain receiver 80d and flows into the inlet pipe 24a from the outlet 78b.

Furthermore, as shown in FIG. 2, the water that has flowed into the inlet pipe 24a flows into the cylinder 14a of the drain valve hydraulic drive unit 14. The water that has flowed into the cylinder 14a pushes up the piston 14b against the biasing force of the spring 14c. At this time, because the clutch mechanism 22 is connected (FIG. 3), the rod 15 connected to the piston 14b and the drain valve 12 connected to this rod 15 are also pulled up, and the drain valve 12 moves away from the drain port 10a. In other words, the drain valve 12 is driven and opened by the driving force of the drain valve hydraulic drive unit 14, which is based on the water supply pressure of the tap water supplied through the water supply pipe 32.

When the drain valve 12 is opened, flush water (tap water) stored in the water storage tank 10 is discharged through the drain port 10a into the bowl portion 2a of the flush toilet body 2, flushing the bowl portion 2a. When flush water is discharged from the water storage tank 10, the water level in the water storage tank 10 drops below a predetermined stop water level _L1 , so the water supply valve float 34 drops. This causes the arm portion 42 (Fig. 2) to rotate, and the float-side pilot valve 44 to open.

When the float side pilot valve port (not shown) is open, the pressure in the pressure chamber 36a does not increase even if the solenoid valve side pilot valve 50 is closed, so the main valve body 38 can be maintained in an open state. Therefore, after the controller 28 energizes the solenoid valve 20 to open the main valve body 38, when a predetermined time has elapsed and the water level in the water storage tank 10 has dropped, the controller 28 stops energizing the solenoid valve 20. As a result, the solenoid valve side pilot valve 50 is closed, but because the float side pilot valve port is open, the main valve body 38 remains unseated from the valve seat 40. In other words, the controller 28 can keep the main valve body 38 open for a long time by simply energizing the solenoid valve 20 for a short time.

Meanwhile, water flowing from the inlet pipe 24a into the pressure chamber 16a of the cylinder 14a of the drain valve hydraulic drive unit 14 pushes the piston 14b up from the position shown in Figure 3 to the position shown in Figure 4. Here, when the piston 14b is in the first position (Figure 3), the side opening 17b provided in the rod 15 is located outside the pressure chamber 16a, so the water in the pressure chamber 16a does not flow out through the side opening 17b, and the pressure in the pressure chamber 16a can be easily increased. When the piston 14b is pushed up and the rod 15 and drain valve 12 are raised to a predetermined position, the clutch mechanism 22 separates the drain valve 12 from the rod 15.

That is, as shown in FIG. 8, the restricting portion 70 protruding downward from the cylinder 14a rotates the movable member 60 to the "disengaged position," and the engagement between the lifting portion 15b of the rod 15 and the abutment portion 68 of the movable member 60 is released. As a result, the rod 15 remains pushed upward together with the piston 14b, while the drain valve 12 descends under its own weight. However, the engagement protrusion 12c (FIG. 5) of the detached drain valve 12 engages with the engagement portion 26b of the drain valve float mechanism 26, preventing the drain valve 12 from descending. As a result, the drain port 10a of the water storage tank 10 remains open, and water continues to be discharged from the water storage tank 10.

On the other hand, when the piston 14b is pushed up from the first position shown in FIG. 3 to the second position shown in FIG. 4, the side opening 17b provided in the rod 15 moves from the outside of the cylinder 14a into the pressure chamber 16a. That is, as shown in FIG. 4, when the side opening 17b moves above the upper end of the sleeve 14f provided in the cylinder 14a, the side opening 17b opens into the pressure chamber 16a. As a result, the pressure chamber 16a and the back pressure chamber 16b in the cylinder 14a are communicated through the communication flow path 17. That is, the water that flows into the pressure chamber 16a flows into the communication flow path 17 from the side opening 17b, and flows into the back pressure chamber 16b through the upper end opening 17a.

In addition, when the upper edge 17c of the horizontally oriented side opening 17b moves above the upper end of the sleeve 14f, the opening area of the side opening 17b into the pressure chamber 16a suddenly widens, and the water in the pressure chamber 16a rapidly flows into the back pressure chamber 16b. The water that flows into the back pressure chamber 16b flows out of the cylinder 14a through the outflow pipe 24b. At this time, the outflow guide portion 14g provided on the ceiling surface of the cylinder 14a guides the water that flows out from the upper end opening 17a toward the outflow pipe 24b. The water that flows out through the outflow pipe 24b is branched at the outflow pipe branching portion 24c (Figure 2) and flows into the water storage tank 10 and the overflow pipe 10b, respectively. In addition, some of the water that flows into the cylinder 14a from the inlet pipe 24a flows out from the gap 14d between the inner wall of the sleeve 14f of the cylinder 14a and the rod 15, and this water flows into the water tank 10.

Next, when the water level in the water storage tank 10 drops to a second predetermined water level lower than the stop water level _L1 , the float portion 26a (FIG. 5) of the drain valve float mechanism 26 drops, which moves the engagement portion 26b to the disengagement position shown by imaginary lines in FIG. 5. This releases the engagement between the engagement protrusion 12c of the drain valve 12 and the engagement portion 26b, and the drain valve 12 starts to drop again. After that, the drain valve 12 closes the drain outlet 10a of the water storage tank 10, and the discharge of flush water to the flush toilet body 2 is stopped. Since the valve seat 40 in the water supply control device 18 remains open even after the drain outlet 10a is closed, water supplied from the water supply pipe 32 flows into the drain valve hydraulic drive portion 14, and the water flowing out of the drain valve hydraulic drive portion 14 flows into the water storage tank 10 through the outflow pipe 24b, so the water level in the water storage tank 10 rises.

When the water level in the water storage tank 10 rises to a predetermined water level _L1 , the water supply valve float 34 (FIG. 2) rises, and the float-side pilot valve 44 is moved via the arm portion 42, and the float-side pilot valve 44 is closed. This closes the float-side pilot valve port (not shown) and the pilot valve port (not shown) of the main valve body 38, so that the pressure in the pressure chamber 36a rises and the main valve body 38 seats on the valve seat 40. As a result, the water supply from the water supply control device 18 is stopped. When the water supply from the water supply control device 18 is stopped, the piston 14b of the drain valve water pressure drive unit 14 is pushed down by the biasing force of the spring 14c, and the rod 15 is also pushed down accordingly.

When the rod 15 is pushed down together with the piston 14b (Figure 9), the rod 15 and the drain valve 12, which had been disconnected by the clutch mechanism 22, are reconnected. That is, as shown in Figure 10, the abutted portion 15d of the descending rod 15 abuts against the movable member 60, rotating the movable member 60 to the "engagement position," and engaging the lifting portion 15b of the rod 15 with the abutting portion 68 of the movable member 60 (Figure 7). Therefore, the next time a toilet flush is performed, both the rod 15 and the drain valve 12 are pulled up by the piston 14b. This completes one toilet flush, and the flush toilet device 1 returns to its standby state for toilet flushing.

Next, the operation of the drain/vacuum breaker valve device 30 after the water supply from the water supply control device 18 is stopped will be described.
When the water supply from the water supply control device 18 is stopped, the dynamic pressure due to the water supply no longer acts on the supply water receiving portion 80b (FIG. 13) of the flap valve body 80 provided in the drain/vacuum breaker valve device 30. As a result, the flap valve body 80 is rotated from the state shown in FIG. 13 to the state shown in FIG. 12 by the biasing force of the coil spring 84, etc., and the intake/drain opening 74c is opened. On the other hand, when the water supply from the water supply control device 18 is stopped, the piston 14b (FIG. 4) of the drain valve water pressure drive unit 14, which had been pushed up to the second position, is pushed down by the biasing force of the spring 14c. As a result, most of the water filled in the pressure chamber 16a of the cylinder 14a flows back toward the drain/vacuum breaker valve device 30 through the inlet pipe 24a.

Water that flows back from the inlet pipe 24a to the drain/vacuum breaker valve device 30 flows into the valve body case 72 through the outlet 78b of the water pipe attachment part 78a, as shown by the solid arrow in FIG. 12, and flows out over the lower edge 74e of the intake/drain opening 74c. Water that flows out from the intake/drain opening 74c of the drain/vacuum breaker valve device 30 is discharged into the water storage tank 10. Here, since the lower edge 74e of the intake/drain opening 74c is formed in a straight line facing the horizontal direction, a relatively large flow path is secured for discharging the backflowing water when the intake/drain opening 74c is opened even slightly. In this way, water that flows back from the drain valve hydraulic drive part 14 can be quickly discharged, so that the water remaining in the cylinder 14a is quickly discharged, and the flushing water tank device 4 can be quickly restored to its initial state.

In addition, since the outlet 78b is provided below the inlet 76c, water that flows back into the drain/vacuum breaker valve device 30 through the outlet 78b can be prevented from flowing back into the inlet 76c. Furthermore, since the area of the intake/drain opening 74c is formed larger than the area of the outlet 78b, the intake/drain opening 74c is not filled with water that flows back through the outlet 78b, and the backflowing water is quickly discharged. In addition, since the orifice 24d (Figure 2), which is a flow rate suppression means, is provided in the flow path between the drain/vacuum breaker valve device 30 and the drain valve water pressure drive unit 14, it is possible to prevent a large amount of water from flowing back from the drain/vacuum breaker valve device 30, and it is possible to reliably prevent the intake/drain opening 74c from being filled with water. With these configurations, it is possible to reliably prevent water that flows back into the drain/vacuum breaker valve device 30 through the outlet 78b from flowing back into the upstream water supply control device 18. In this embodiment, an orifice 24d is provided as a flow rate suppression device, but the flow rate of backflowing water can also be suppressed by other configurations.

On the other hand, when the intake/drain opening 74c of the drain/vacuum break valve device 30 is opened, outside air is sucked into the valve body case 72 through the upper part of the intake/drain opening 74c, as shown by the dashed arrow in FIG. 12. That is, since the intake/drain opening 74c is formed vertically long, water that has flowed back through the outlet 78b is discharged from the lower part of the intake/drain opening 74c, and at the same time, outside air can be easily introduced from the upper part of the intake/drain opening 74c. In this way, even if the water supply from the water supply control device 18 is stopped and the water pipe attachment part 76a side becomes negative pressure, outside air is sucked in from the drain/vacuum break valve device 30, so that the water that has flowed back from the inlet pipe 24a is prevented from flowing back to the water supply control device 18. Here, since the upper edge 74d of the intake/drain opening 74c is formed in a straight line toward the horizontal direction, even if the intake/drain opening 74c is opened even slightly, a relatively large flow path for sucking in outside air is secured.

Furthermore, as shown in FIG. 12, the inlet 76c provided at the lower end of the water pipe mounting portion 76a is located below the upper edge 74d of the intake/drain opening 74c, so that the water in the valve body case 72 does not flow back into the water pipe mounting portion 76a, and backflow can be reliably prevented. In this way, when the supply of water from the upstream side is stopped, the flap valve body 80 of the drain/vacuum breaker valve device 30 opens the upstream side to the atmosphere and at the same time operates to drain the backflowing water from the drain valve hydraulic drive unit 14. The drain/vacuum breaker valve device 30 has both the function of discharging water that has flowed back from the downstream side and the function of drawing outside air into the pipeline, and the intake/drain opening 74c functions as an intake port for outside air and a drain port for water in the pipeline.

Next, the forces acting to open and close the flap valve body 80 will be described with reference to FIG.
FIG. 14 is a diagram for explaining the forces acting on the flap valve body 80 of the drain/vacuum breaker valve device 30 in each operating condition.

First, in the state shown in FIG. 14(a) before the start of water supply from the water supply control device 18, the flap valve body 80 of the drain/vacuum breaker valve device 30 is in a standby position. In this state, the only force acting on the flap valve body 80 is gravity, and the flap valve body 80 is rotated to the standby position (the state shown in FIG. 12) in which its center of gravity is at its lowest, and the intake/drain opening 74c is open. Note that when the flap valve body 80 is in the standby position, the coil spring 84 (FIG. 12) is not in contact with the flap valve body 80, and no biasing force from the coil spring 84 acts on the flap valve body 80.

Next, as shown in FIG. 14(b), when water supply from the water supply control device 18 starts, the supply water receiving portion 80b of the flap valve body 80 is pushed by the dynamic pressure of the water flowing in from the inlet 76c, and a force moment T1 based on the dynamic pressure acts on the flap valve body 80. This force moment T1 rotates the flap valve body 80 in a direction that closes the intake/drain opening 74c. In other words, the force moment T1 based on the dynamic pressure of the flowing in water overcomes the force moment Tg based on gravity that tries to maintain the flap valve body 80 in the standby position (T1-Tg>0), and the flap valve body 80 is rotated. Furthermore, when the flap valve body 80 is rotated in the closing direction by a predetermined amount or more, the coil spring 84 (FIG. 12) comes into contact with the flap valve body 80, and the force moment Tb based on the biasing force of the coil spring 84 also acts on the flap valve body 80. The flap valve body 80 overcomes the biasing force of the coil spring 84 (T1-Tg-Tb>0) and rotates in the closing direction.

Furthermore, when the flap valve body 80 is rotated and the intake/drain opening 74c approaches a closed state, the flap valve body 80 is also pressed in the direction of closure by the force moment Ts based on the static pressure of the water in the drain/vacuum breaker valve device 30, as shown in FIG. 14(c).

Next, as shown in FIG. 14(d), when the intake/drain opening 74c is closed by the flap valve body 80 and water supply from the water supply control device 18 continues, the flap valve body 80 is closed by static pressure and dynamic pressure. That is, the closed state of the intake/drain opening 74c is stably maintained by the force moment T1 based on the dynamic pressure of the water supply acting on the supply water receiving portion 80b of the flap valve body 80 and the force moment Ts based on the static pressure acting on the back surface of the flap valve body 80 (T1+Ts-Tg-Tb>0).

Furthermore, as shown in FIG. 14(e), when the water supply from the water supply control device 18 is stopped, the force moment T1 based on the dynamic pressure of the water supply no longer acts on the flap valve body 80. In this state, the sum of the force moments (Tg, Tb) in the direction to open the flap valve body 80 becomes greater than the force moment (Ts) in the direction to close it (Ts-Tg-Tb<0). As a result, the flap valve body 80 begins to rotate in the opening direction. Here, since the force based on the static pressure acting on the flap valve body 80 is proportional to the opening area of the intake/drain opening 74c, if the opening area is set too large, the force moment Ts based on the static pressure becomes too large, making it difficult to open the flap valve body 80.

Next, as shown in FIG. 14(f), when the flap valve body 80 is opened, air is introduced into the drain/vacuum breaker valve device 30 through the intake/drain opening 74c, and water in the drain/vacuum breaker valve device 30 is discharged through the intake/drain opening 74c. By introducing air into the drain/vacuum breaker valve device 30, the force moment Ts based on the static pressure no longer acts on the flap valve body 80 (Ts = 0). In addition, when the flap valve body 80 is rotated in the opening direction by more than a predetermined amount, the tip of the coil spring 84 (FIG. 12) separates from the flap valve body 80, and the force moment Tb based on the biasing force of the coil spring 84 also no longer acts (Tb = 0). Even in this state, the flap valve body 80 remains open (-Tg < 0).

Furthermore, as shown in FIG. 14(g), when water begins to flow back from the drain valve hydraulic drive unit 14 side through the outlet 78b, the flap valve body 80 is also rotated in the opening direction by the force moment T2 based on the dynamic pressure of the water flowing back through the outlet 78b (-Tg-T2<0).

Next, as shown in FIG. 14(h), when the discharge of the water that has flowed back through the outlet 78b is completed, the flap valve body 80 is maintained in the open state only by the force moment Tg based on gravity acting on the flap valve body 80, and returns to the state before the water supply from the water supply control device 18 started. In this embodiment, the drain/vacuum breaker valve device 30 ensures that the operations in FIG. 14(a) to (h) are performed by appropriately setting the force moments T1, T2, Tg, Tb, and Ts acting on the flap valve body 80.

As described above, the drain/vacuum breaker valve device 30 provided in the flush water tank device 4 of this embodiment not only drains backflow water but also functions as a negative pressure breaker (vacuum breaker) to introduce air into the pipeline, but is different from the normal negative pressure breaker valves provided in conventional flush water tank devices and the like. This will be explained below with reference to Figure 24.

FIG. 24 is a cross-sectional view showing a typical configuration of a negative pressure release valve, and shows the configuration of the negative pressure release valve disclosed in Japanese Patent Application Laid-Open No. 2013-204389 as an example.
As shown in FIG. 24, a normal negative pressure release valve 90 is composed of a negative pressure release valve body 92 and an atmospheric opening 94 that is opened and closed by the negative pressure release valve body 92. In the example shown in FIG. 24, the negative pressure release valve 90 is provided in the middle of the flow path from the main valve port 96a to the outlet 98. The flush water that flows in from the main valve port 96a and flows out from the outlet 98 can be used to supply to the water storage tank or to refill the toilet body via a make-up water hose and an overflow pipe. The negative pressure release valve body 92 is a valve body that is arranged to be movable in the vertical direction, and is configured to close the atmospheric opening 94 when moved upward. On the other hand, the atmospheric opening 94 is an opening formed in a wall surface oriented in the horizontal direction, and opens vertically upward. In the example shown in FIG. 24, the upper side of the atmospheric opening 94 is open to the atmosphere.

As shown in FIG. 24, when the main valve body 96b is opened, water flows in from the main valve port 96a, and the water flows upward along the flow path. The negative pressure release valve body 92 is pushed upward by the dynamic pressure of the water flowing upward, and closes the atmospheric opening 94. When the atmospheric opening 94 is closed, the water flowing in from the main valve port 96a flows out to the outlet 98. On the other hand, when the inflow of water from the main valve port 96a is stopped, the dynamic pressure no longer acts on the negative pressure release valve body 92, so the negative pressure release valve body 92 is moved downward by gravity, and the atmospheric opening 94 is opened to the atmosphere. Therefore, when negative pressure occurs upstream of the main valve port 96a, the atmosphere is introduced into the flow path from the atmospheric opening 94, and the negative pressure is broken. Therefore, the water downstream of the negative pressure release valve 90 is sucked upstream by the negative pressure generated upstream of the main valve port 96a, and it is possible to prevent water from flowing back upstream.

However, with a normal negative pressure release valve 90 with the structure shown in FIG. 24, it is not possible to introduce air into the pipeline and simultaneously discharge water that has flowed back from the downstream side. That is, with the structure shown in FIG. 24, in order to discharge backflow water from the atmospheric opening 94, the water level that has flowed back from the water storage tank or the like to the outlet 98 must rise above the atmospheric opening 94. In this state, the atmospheric opening 94 is filled with water, and it is no longer possible to introduce air from this atmospheric opening 94. Thus, with a normal negative pressure release valve, it is not possible to introduce air and discharge backflow water at the same time, and it is not possible to operate it like the drain/vacuum breaker valve device 30 in this embodiment.

According to the flush water tank device 4 of the first embodiment of the present invention, when the supply of water from the upstream side is stopped, the drain/vacuum breaker valve device 30 drains the water that has flowed back from the drain valve hydraulic drive unit 14 (FIG. 12), so that the water that has flowed into the cylinder 14a (FIG. 2) of the drain valve hydraulic drive unit 14 can be discharged with a simple mechanism. This allows the piston 14b to be returned to its initial position quickly, and the next toilet flush can be restored in a short time. Also, according to the flush water tank device 4 of this embodiment, when the supply of water from the upstream side is stopped, the drain/vacuum breaker valve device 30 opens the upstream side to the atmosphere, so that if the upstream side of the drain/vacuum breaker valve device 30 becomes negative pressure, the atmosphere is sucked in, preventing water from flowing back to the upstream side.

In addition, according to the flush water tank device 4 of this embodiment, the inlet 76c is provided above the outlet 78b (FIG. 12), so that water that has flowed back from the drain valve hydraulic drive unit 14 to the outlet 78b can be reliably prevented from flowing back into the inlet 96c. In addition, the intake/drain opening 74c, which is opened and closed by the flap valve body 80, is formed on a vertical surface, so that water that has flowed back from the drain valve hydraulic drive unit 14 to the outlet 78b can be discharged from the lower part of the intake/drain opening 74c, and at the same time, air can be sucked in from the upper part of the intake/drain opening 74c, allowing drainage and intake to be performed simultaneously.

Furthermore, according to the flush water tank device 4 of this embodiment, the area of the intake/drain opening 74c is larger than the area of the outlet 78b of the drain/vacuum breaker valve device 30, so that water that has flowed back from the drain valve hydraulic drive unit 14 to the outlet 78b can be drained while also reliably sucking in air.

In addition, according to the flush water tank device 4 of this embodiment, the intake/drain opening 74c is formed longer in the vertical direction than in the horizontal direction (Figure 11), so that backflowing water can be drained and air can be drawn in reliably with a small opening area.

Furthermore, according to the flush water tank device 4 of this embodiment, the flap valve body 80 of the drain/vacuum break valve device 30 opens and closes the intake/drain opening 74c by rotating, so that the opening and closing mechanism of the intake/drain opening 74c can be configured compactly, and the design freedom of the drain/vacuum break valve device 30 can be increased.

In addition, according to the flush water tank device 4 of this embodiment, the support shaft 80a on which the flap valve body 80 rotates is positioned outside the vertical projection plane of the intake/drain opening 74c (Figure 12), so that the crushing allowance of the gasket 82 that seals between the edge of the intake/drain opening 74c and the flap valve body 80 can be reliably secured, and the intake/drain opening 74c can be reliably closed.

Furthermore, according to the flush water tank device 4 of this embodiment, the lower edge 74e of the intake/drain opening 74c extends horizontally (Figure 11), and backflowing water is discharged beyond this lower edge 74e into the water storage tank 10, so that a large flow path area for the drainage water flowing beyond the lower edge 74e can be secured, and the rise in the water level within the drainage/vacuum breaker valve device 30 can be suppressed.

In addition, according to the flush water tank device 4 of this embodiment, the upper edge 74d of the intake/drain opening 74c extends horizontally (Figure 11), so that even when water is being discharged from the intake/drain opening 74c, a large flow path area can be secured for drawing in outside air through the intake/drain opening 74c, ensuring that atmospheric air can be drawn in reliably.

Furthermore, according to the flush water tank device 4 of this embodiment, when water is not being supplied to the drain/vacuum breaker valve device 30, the flap valve body 80 is in a standby position (Figure 12) with the center of gravity at its lowest position, so that the valve body can be returned to the standby position by its own weight with a simple structure.

In addition, according to the flush water tank device 4 of this embodiment, the flap valve body 80 is equipped with a weight 82a, so that the gravity acting on the flap valve body 80 can be increased, and the flap valve body 80 can be reliably returned to the standby position with a simple structure.

Furthermore, according to the flush water tank device 4 of this embodiment, a coil spring 84 is provided that biases the flap valve body 80 in the direction of opening the intake/drain opening 74c (Figure 13), so that when the supply of water to the drain/vacuum breaker valve device 30 is stopped, the intake/drain opening 74c can be reliably opened.

In addition, according to the flush water tank device 4 of this embodiment, when the intake/drain opening 74c is open to a predetermined amount or more, no biasing force acts on the flap valve body 80 (Fig. 12), so when water supply to the drain/vacuum breaker valve device 30 begins, the flap valve body 80 can be easily moved and closed. On the other hand, when the opening of the intake/drain opening 74c is less than the predetermined amount, a biasing force acts on the flap valve body 80 (Fig. 13), so when the supply of water to the drain/vacuum breaker valve device is stopped, the valve body can be easily opened.

Furthermore, according to the flush water tank device 4 of this embodiment, the flow rate suppression means, orifice 24d (Figure 2), suppresses the flow rate of water flowing back to the drain/vacuum breaker valve device 30, preventing a large flow rate of water from flowing back from the drain valve hydraulic drive unit 14, filling the intake/drain opening 74c with water and preventing outside air from being drawn in.

Next, a flush water tank apparatus and a flush toilet apparatus equipped with the same according to a second embodiment of the present invention will be described with reference to Figures 15 to 17.
The flush water tank apparatus of this embodiment differs from the first embodiment described above in the structure of the drain/vacuum breaker valve device, but the other configurations are the same as those of embodiment 1. Therefore, only the points of the second embodiment of the present invention that differ from the first embodiment will be described here, and a description of the similar configurations, actions, and effects will be omitted.

Figure 15 is a perspective view of a drain/vacuum break valve device provided in a flush water tank device according to a second embodiment of the present invention. Figure 16 is a cross-sectional view of the drain/vacuum break valve device when water is not being supplied from the water supply control device, and Figure 17 is a cross-sectional view of the drain/vacuum break valve device when water is being supplied.

As shown in FIGS. 15 to 17 , the drain/vacuum breaker valve device 130 in this embodiment has a valve body case 172 , a flap valve body 180 which is a valve body, and a packing 182 .
In addition, the valve body case 172 is composed of a box-shaped main body 174, a cover member 176 attached to the upper surface of the main body 174, an inlet pipe connecting member 177 (Figure 16), and an outlet pipe connecting member 178 attached to the lower side of the main body 174.

The main body 174 of the valve body case 172 is configured as a roughly trapezoidal box expanding downward, with one side oriented vertically and the other oriented inclined. The top surface of the main body 174 is open, and a cover member 176 is attached to cover this opening. Furthermore, an upper mounting portion 174a is provided on the upper portion of the vertically oriented side surface of the main body 174, and an inlet pipe connecting member 177 is attached thereto. Furthermore, a lower mounting portion 174b is provided on the lower portion of the inclined side surface of the main body 174, and an outlet pipe connecting member 178 is attached thereto. Furthermore, an intake/drain opening 174c is provided on the inclined side surface of the main body 174 above the lower mounting portion 174b.

The intake/drain opening 174c is a vertically long rectangular opening. When the flap valve body 180 is open, outside air is drawn in through the intake/drain opening 174c, and water that has flowed back from the inlet pipe 24a flows out and is discharged into the water tank 10. That is, the intake/drain opening 174c is an opening formed on the inclined side of the main body 174, and is formed longer in the vertical direction than in the horizontal direction. In addition, the upper edge 174d of the intake/drain opening 174c is formed linearly so as to extend horizontally, and the lower edge 174e extends in an arc shape. Water that has flowed back into the drain/vacuum breaker valve device 130 is discharged into the water tank 10 beyond the lower edge 174e.

The inlet pipe connection member 177 is provided with a water pipe attachment portion 177a extending horizontally so as to penetrate the main body portion 174. One end of the water pipe attachment portion 177a protrudes toward the outside of the main body portion 174 in the opposite direction to the intake/drain opening 174c, and a water pipe extending from the water supply control device 18 (FIG. 2) is connected thereto. Meanwhile, the other end of the water pipe attachment portion 177a opens into the inside of the main body portion 174, and water supplied from the water supply control device 18 flows into the drain/vacuum breaker valve device 130 through the inlet 177b at the other end of the water pipe attachment portion 177a. This inlet 177b opens toward the back surface of the flap valve body 180 arranged in the drain/vacuum breaker valve device 130. That is, the water flowing out of the water supply control device 18 passes through the water pipe attachment portion 177a provided on the upper side of the drain/vacuum breaker valve device 130 and flows horizontally into the valve body case 172 from the inlet 177b.

The outlet pipe connection member 178 is provided with a water pipe attachment portion 178a that protrudes horizontally, and the inlet pipe 24a is connected to the water pipe attachment portion 178a. Therefore, water supplied from the water supply control device 18 and flowing into the valve body case 172 flows out of the drain/vacuum breaker valve device 130 through the outlet 178b at the upstream end of the water pipe attachment portion 178a, and is supplied to the drain valve hydraulic drive portion 14 via the inlet pipe 24a. In other words, the water that flows into the drain/vacuum breaker valve device 130 is supplied to the drain valve hydraulic drive portion 14 through the outlet 178b. The area of the intake/drain opening 174c is formed larger than the area of the outlet 178b, and the inlet 177b is provided above the outlet 178b.

The flap valve body 180 is a generally rectangular plate-shaped member rotatably attached inside the valve body case 172, and is configured to open and close the intake/drain opening 174c. In addition, a support shaft 180a, which is a central axis extending horizontally, is formed at the upper end of the flap valve body 180. This support shaft 180a is rotatably supported by a bearing portion 176a provided on the cover member 176, and the flap valve body 180 is rotated between the state shown in FIG. 16 and the state shown in FIG. 17. The support shaft 180a is located outside the vertical projection plane of the intake/drain opening 174c. In other words, the support shaft 180a is located outside the projection plane of the intake/drain opening 174c formed by shining light perpendicularly onto the surface (inclined surface) on which the intake/drain opening 174c is formed.

As described above, the water pipe attachment portion 177a is disposed on the upper rear side of the flap valve body 180, and water supplied from the water supply control device 18 is discharged from the inlet 177b toward the rear side of the flap valve body 180. Therefore, when water flows in through the inlet 177b, the rear side of the flap valve body 180 is pushed toward the intake/drain opening 174c, and the flap valve body 180 is rotated from the state shown in FIG. 16 to the state shown in FIG. 17.

Furthermore, the flap valve body 180 has a valve plate portion 180b extending downward from the support shaft 180a, and a drainage receiving portion 180c provided on the lower side of the valve plate portion 180b. The valve plate portion 180b is arranged to face the intake/drain opening 174c provided on the inclined side surface of the main body portion 174, and is configured to cover the intake/drain opening 174c when the flap valve body 180 is rotated to the state shown in Figure 17. In addition, a thin plate-shaped packing 182 is attached to the surface of the valve plate portion 180b facing the intake/drain opening 174c, and when the flap valve body 180 is rotated to the state shown in Figure 17, the gap between the valve plate portion 180b and the intake/drain opening 174c is sealed. Here, the support shaft 180a of the flap valve body 180 is positioned outside the vertical projection plane of the intake/drain opening 174c, so that when the flap valve body 180 is rotated to the state shown in FIG. 17, the crushing allowance of the packing 182 can be reliably secured.

The drain receiver 180c is formed on the underside of the valve plate portion 180b and is positioned to face the outlet port 178b of the outlet pipe connection member 178. Therefore, when water flows back from the inlet pipe 24a to the water pipe attachment portion 178a, the drain receiver 180c is pushed and the flap valve body 180 is rotated from the state shown in FIG. 17 to the state shown in FIG. 16. The water that flows back from the water pipe attachment portion 178a flows out through the intake/drain opening 174c and is discharged into the water storage tank 10.

Furthermore, the valve plate portion 180b is provided with a weight attachment portion 180d so as to protrude from the intake/drain opening 174c, and a weight 182a is attached to the tip of this weight attachment portion 180d. By attaching this weight 182a, the center of gravity of the entire flap valve body 180 is located on the side closer to the intake/drain opening 174c than the support shaft 180a (the right side in Figures 16 and 17). As a result, a force moment acts on the flap valve body 180 in the clockwise direction in Figure 17 around the support shaft 180a, and in a standby state where the static pressure and dynamic pressure of water are not acting, the flap valve body 180 is rotated to the position shown in Figure 16. That is, when water is not supplied to the drain/vacuum breaker valve device 130, the flap valve body 180 is in the standby position shown in Figure 16, where the center of gravity of the flap valve body 180 is at its lowest position.

As a modified example, a cover can be attached to the outer peripheral surface of the main body 174 so as to cover the intake/drain opening 174c. This cover can prevent the water discharged from the intake/drain opening 174c into the water storage tank 10 from splashing. In addition, the discharged water collides with the surface of the cover facing the intake/drain opening 174c, causing the water to temporarily accumulate near the flap valve body 180, making it easier to rotate the flap valve body 180 in the opening direction.

As another modification, a space may be formed below the outlet 178b in the main body 174, and the flap valve body 180 may be extended into this space. That is, a tip extending downward from the lower end of the drainage receiving portion 180c may be formed. According to this modification, when water flows back from the inlet pipe 24a to the water pipe attachment portion 178a, the part forming the lower edge 174e can guide the backflowing water to the drainage receiving portion 180c. Also, when water flows in through the inlet 177b, the part forming the lower edge 174e prevents water from being discharged from the intake/drain opening 174c, increasing the internal pressure, and since there is no part protruding into the main body 174 at the lower position opposite the part forming the lower edge 174e, water can flow out smoothly from the outlet 178b. Furthermore, a biasing spring and a spring cover covering this biasing spring may be provided between the tip and the inner wall of the main body 174.

Next, the operation of the flush water tank apparatus and flush toilet apparatus according to the second embodiment of the present invention will be described.
First, when a command signal for flushing the toilet is received, water is supplied from the water supply control device 18, and water flows into the drain/vacuum breaker valve device 130. When water flows into the drain/vacuum breaker valve device 130, the back surface of the flap valve body 180 is pushed toward the intake/drain opening 174c, as shown in Fig. 16, and the flap valve body 180 is rotated to the position shown in Fig. 17. This causes the intake/drain opening 174c of the drain/vacuum breaker valve device 130 to be closed by the flap valve body 180. Water that flows in from the inlet 177b of the drain/vacuum breaker valve device 130 flows into the valve body case 172, as shown by the arrow in Fig. 17, and further flows into the inlet pipe 24a from the outlet 178b, bypassing the drain receiving portion 180c.

As a result, flush water is supplied to the drain valve hydraulic drive unit 14. The toilet flushing action by the flush water tank device after flush water is supplied to the drain valve hydraulic drive unit 14 is the same as in the first embodiment described above, so a description thereof will be omitted.

Next, when the water supply from the water supply control device 18 is stopped after the toilet flush is completed, the dynamic pressure from the water supply no longer acts on the back surface of the valve plate portion 180b (FIG. 17) of the flap valve body 180 provided in the drain/vacuum breaker valve device 130. As a result, the flap valve body 180 is rotated from the state shown in FIG. 17 to the state shown in FIG. 16 by gravity acting on the flap valve body 180, and the intake/drain opening 174c is opened. On the other hand, when the water supply from the water supply control device 18 is stopped, the piston 14b (FIG. 4) of the drain valve water pressure drive unit 14, which had been pushed up to the second position, is pushed down by the biasing force of the spring 14c. As a result, most of the water that had filled the pressure chamber 16a of the cylinder 14a flows back through the inlet pipe 24a toward the drain/vacuum breaker valve device 130.

Water that flows back from the inlet pipe 24a into the drain/vacuum breaker valve device 130 flows into the valve body case 172 through the outlet 178b of the water pipe attachment part 178a, as shown by the solid arrow in FIG. 16, and flows out over the lower edge 174e of the intake/drain opening 174c. Water that flows out from the intake/drain opening 174c of the drain/vacuum breaker valve device 130 is discharged into the water storage tank 10. In addition, since the outlet 178b is provided below the inlet 177b, water that flows back into the drain/vacuum breaker valve device 130 through the outlet 178b can be prevented from flowing back into the inlet 177b.

Furthermore, since the area of the intake/drain opening 174c is formed larger than the area of the outlet 178b, the intake/drain opening 174c is not filled with water that flows back through the outlet 178b, and the backflowing water is quickly discharged. This configuration reliably prevents water that flows back through the outlet 178b into the drain/vacuum breaker valve device 130 from flowing back into the upstream water supply control device 18. In addition, since the backflowing water can be quickly discharged from the drain valve hydraulic drive unit 14, the water remaining in the cylinder 14a is quickly discharged, and the flush water tank device can be quickly restored to its initial state.

On the other hand, when the intake/drain opening 174c of the drain/vacuum break valve device 130 is opened, outside air is sucked into the valve body case 172 through the upper part of the intake/drain opening 174c, as shown by the dashed arrow in Fig. 16. That is, since the intake/drain opening 174c is formed vertically, water that has flowed back through the outlet 178b is discharged from the lower part of the intake/drain opening 174c, and at the same time, outside air can be easily introduced from the upper part of the intake/drain opening 174c. In this way, even if the water supply from the water supply control device 18 is stopped and the water pipe attachment part 177a side becomes negative pressure, outside air is sucked in from the drain/vacuum break valve device 130, so that the water that has flowed back from the inlet pipe 24a is prevented from flowing back into the water supply control device 18. Here, the upper edge 174d of the intake/drain opening 174c is formed in a straight line in the horizontal direction, so that even if the intake/drain opening 174c is opened even slightly, a relatively large flow path is secured for drawing in outside air.

Furthermore, as shown in FIG. 16, the inlet 177b is located below the upper edge 174d of the intake/drain opening 174c, so that the water in the valve body case 172 does not flow back into the water pipe mounting portion 177a, and backflow can be reliably prevented. In this way, when the supply of water from the upstream side is stopped, the flap valve body 180 of the drain/vacuum breaker valve device 130 opens the upstream side to the atmosphere and at the same time operates to drain the backflowing water from the drain valve hydraulic drive unit 14. The drain/vacuum breaker valve device 130 has both the function of discharging water that has flowed back from the downstream side and the function of drawing outside air into the pipeline, and the intake/drain opening 174c functions as an intake port for outside air and a drain port for water in the pipeline.

According to the second embodiment of the flush water tank device of the present invention, the intake/drain opening 174c is provided on an inclined surface (Figure 16), so that the flap valve body 180 can be easily returned to the standby position by its own weight.

Next, a flush water tank apparatus and a flush toilet apparatus equipped with the same according to a third embodiment of the present invention will be described with reference to Figures 18 to 21.
The flush water tank apparatus of this embodiment differs from the first embodiment described above in the structure of the drain/vacuum breaker valve device, but the other configurations are the same as those of embodiment 1. Therefore, only the points of the third embodiment of the present invention that differ from the first embodiment will be described here, and a description of the similar configurations, actions, and effects will be omitted.

Figure 18 is a perspective view of a drain/vacuum break valve device provided in a flushing water tank device according to a third embodiment of the present invention. Figure 19 is a perspective view of the drain/vacuum break valve device with a portion of the case cut away, showing a state in which water is not being supplied from the water supply control device. Figure 20 is a perspective view of the drain/vacuum break valve device with a portion of the case cut away, showing a state in which water is being supplied from the water supply control device. Figure 21 is a horizontal cross-sectional view showing the internal structure of the drain/vacuum break valve device.

As shown in FIGS. 18 to 21 , the drain/vacuum breaker valve device 230 in this embodiment has a valve body case 272 , a flap valve body 280 which is a valve body, and a packing 282 .
The valve body case 272 is composed of a cylindrical main body 274 and a lid member 276 attached to the upper surface of the main body 274 .

The main body 274 of the valve body case 272 is generally cylindrical with its central axis oriented vertically. The top surface of the main body 274 is open, and a lid member 276 is attached to cover this opening. Furthermore, an inlet water pipe attachment portion 274a is provided on the upper part of the outer circumferential surface of the main body 274, and an outlet water pipe attachment portion 274b is provided on the lower part of the outer circumferential surface. An intake/drain opening 274c is also provided on the outer circumferential surface of the main body 274.

Furthermore, a cover 278 (Fig. 21) is attached to the outer periphery of the main body 274. This cover 278 is attached so as to cover the intake/drain opening 274c provided on the side of the main body 274. Water flowing out from the intake/drain opening 274c flows out to the outside of the drain/vacuum breaker valve device 230 through the gap between the cover 278 and the outer periphery of the main body 274.

The inlet water pipe mounting portion 274a is a circular pipe formed so as to protrude horizontally from the upper side surface of the main body portion 274 in a direction perpendicular to the central axis of the main body portion 274. The outlet water pipe mounting portion 274b is a circular pipe formed so as to protrude horizontally from the lower side surface of the main body portion 274 in a direction perpendicular to the central axis of the main body portion 274. Furthermore, the base end of the inlet water pipe mounting portion 274a opens to the inside of the main body portion 274 as an inlet 274d (FIG. 21) through which the supplied water flows in, and the base end of the outlet water pipe mounting portion 274b opens to the inside of the main body portion 274 as an outlet 274e through which the water in the drain/vacuum breaker valve device 230 flows out.

The inlet 274d at the base end of the inlet water pipe attachment part 274a is provided above the outlet 274e at the base end of the outlet water pipe attachment part 274b. The outlet 274e is provided below the lower end of the intake/drain opening 274c formed on the side of the main body part 274. A water pipe extending from the water supply control device 18 (Figure 2) is connected to the inlet water pipe attachment part 274a, and water supplied from the water supply control device 18 flows into the valve body case 272 through the inlet 274d. The inlet water pipe attachment part 274b is connected to the inlet pipe 24a, and water that flows into the valve body case 272 flows out through the outlet 274e.

In addition, the outlet water pipe mounting portion 274b is provided on the opposite side of the inlet water pipe mounting portion 274a, and these inlet water pipe mounting portion 274a and outlet water pipe mounting portion 274b are oriented parallel to each other when viewed from above (Figure 21). Furthermore, the intake/drain opening 274c provided on the outer peripheral surface of the main body portion 274 is oriented in a direction perpendicular to the inlet water pipe mounting portion 274a and the outlet water pipe mounting portion 274b.

The intake/drain opening 274c is a vertically long oval opening (Figure 19). When the flap valve body 280 is open, outside air is drawn in through the intake/drain opening 274c, and water that has flowed back from the inlet pipe 24a flows out and is discharged into the water tank 10. That is, the intake/drain opening 274c is an opening formed on the vertically oriented surface of the main body 274, and is longer in the vertical direction than in the horizontal direction. Water that has flowed back into the drain/vacuum breaker valve device 230 passes over the lower edge of the intake/drain opening 274c and is discharged into the water tank 10.

As shown in FIG. 19, the flap valve body 280 is a member composed of two rectangular plate-shaped parts rotatably attached inside the valve body case 272, and is configured to open and close the intake/drain opening 274c. The flap valve body 280 is composed of a first flat plate portion 280a, a second flat plate portion 280b, and a connecting portion 280c that connects them. The first flat plate portion 280a and the second flat plate portion 280b are joined at one long side so as to form a predetermined angle, and the first flat plate portion 280a and the second flat plate portion 280b are connected by a roughly fan-shaped connecting portion 280c. Also, as shown in FIG. 20, the second flat plate portion 280b extends from near the ceiling surface of the valve body case 272 to the bottom surface. In contrast, the first flat plate portion 280a extends from near the ceiling surface of the valve body case 272 to a position a predetermined distance above the bottom surface, and a gap is provided between the lower end of the first flat plate portion 280a and the bottom surface of the valve body case 272.

Furthermore, a shaft 281 extending in the axial direction is provided inside the cylindrical valve body case 272. This shaft 281 rotatably supports the joint between the first flat plate portion 280a and the second flat plate portion 280b of the flap valve body 280, and the flap valve body 280 is rotated around the shaft 281. When the flap valve body 280 is rotated to the position shown in FIG. 19, the second flat plate portion 280b faces the inlet side water pipe attachment portion 274a, and when it is rotated to the position shown in FIG. 20, the first flat plate portion 280a faces the intake/drain opening 274c. The shaft 281 is disposed outside the vertical projection plane of the intake/drain opening 274c. In other words, the shaft 281 is located outside the projection plane of the intake/drain opening 274c formed by shining light perpendicularly on the intake/drain opening 274c.

Furthermore, as shown in FIG. 20, a torsion coil spring 284 is disposed above the flap valve body 280, and this torsion coil spring 284 is attached so as to surround the periphery of the shaft 281. The flap valve body 280 is biased by the torsion coil spring 284 in the opening direction, that is, so as to rotate from the position shown in FIG. 20 to the position shown in FIG. 19.

As described above, the second flat plate portion 280b of the flap valve body 280 faces the inlet 274d at the base end of the inlet side water pipe attachment portion 274a, and a small disk-shaped packing 283 (Figure 21) is attached to the second flat plate portion 280b at a position facing the inlet 274d. Water supplied from the water supply control device 18 is discharged from the inlet 274d toward the second flat plate portion 280b, so that when water flows in, the second flat plate portion 280b is pressed, and the flap valve body 280 is rotated clockwise in Figure 21. As a result, the flap valve body 280 is rotated from the state shown in Figure 19 to the state shown in Figure 20.

Furthermore, as described above, the first flat plate portion 280a of the flap valve body 280 faces the intake/drain opening 274c, and is configured to cover the intake/drain opening 274c when the flap valve body 280 is rotated to the state shown in FIG. 20. A thin-plate packing 282 (FIG. 19) is attached to the surface of the first flat plate portion 280a facing the intake/drain opening 274c, and when the flap valve body 280 is rotated to the state shown in FIG. 20, the gap between the first flat plate portion 280a and the intake/drain opening 274c is sealed. Here, the shaft 281 supporting the flap valve body 280 is disposed outside the vertical projection plane of the intake/drain opening 274c, so that the crushing allowance of the packing 282 can be reliably secured when the flap valve body 280 is rotated to the state shown in FIG. 20.

On the other hand, if water flows back from the inlet pipe 24a to the outlet water pipe attachment portion 274b, the backflowing water passes through the gap between the first flat portion 280a of the flap valve body 280 and the bottom surface of the valve body case 272 and hits the back surface of the second flat portion 280b. This causes the flap valve body 280 to rotate from the state shown in FIG. 20 to the state shown in FIG. 19. The water that flows back from the outlet water pipe attachment portion 274b flows out through the intake/drain opening 274c and is discharged into the water storage tank 10.

Next, the operation of the flush water tank apparatus and flush toilet apparatus according to the third embodiment of the present invention will be described.
First, when a toilet flush command signal is received, water is supplied from the water supply control device 18, and water flows into the drain/vacuum breaker valve device 230. When water flows into the drain/vacuum breaker valve device 230, the second flat plate portion 280b of the flap valve body 280 is pressed, and the flap valve body 280 is rotated to the position shown in Fig. 20 against the biasing force of the torsion coil spring 284. As a result, the intake/drain opening 274c of the drain/vacuum breaker valve device 230 is closed by the first flat plate portion 280a of the flap valve body 280. Water that flows in from the inlet 274d of the drain/vacuum breaker valve device 230 bypasses the flap valve body 280 within the valve body case 272 and flows into the inlet pipe 24a from the outlet 274e.

As a result, flush water is supplied to the drain valve hydraulic drive unit 14. The toilet flushing action by the flush water tank device after flush water is supplied to the drain valve hydraulic drive unit 14 is the same as in the first embodiment described above, so a description thereof will be omitted.

Next, when the water supply from the water supply control device 18 is stopped after the toilet flush is completed, the dynamic pressure due to the water supply no longer acts on the second flat plate portion 280b of the flap valve body 280 provided in the drain/vacuum breaker valve device 230. As a result, the flap valve body 280 is rotated from the state shown in FIG. 20 to the state shown in FIG. 19 by the biasing force of the torsion coil spring 284, and the intake/drain opening 274c is opened. On the other hand, when the water supply from the water supply control device 18 is stopped, the piston 14b (FIG. 4) of the drain valve water pressure drive unit 14, which had been pushed up to the second position, is pushed down by the biasing force of the spring 14c. As a result, most of the water that had filled the pressure chamber 16a of the cylinder 14a flows back toward the drain/vacuum breaker valve device 230 through the inlet pipe 24a.

Water that flows back from the inlet pipe 24a into the drain/vacuum breaker valve device 230 flows into the valve body case 272 through the outlet 274e of the outlet water pipe mounting portion 274b, as shown by the solid arrow in FIG. 19, and flows out over the lower edge of the intake/drain opening 274c. Water that flows out from the intake/drain opening 274c of the drain/vacuum breaker valve device 230 is discharged into the water storage tank 10. In addition, since the outlet 274e is provided below the inlet 274d, water that flows back into the drain/vacuum breaker valve device 230 through the outlet 274e can be prevented from flowing back into the inlet 274d.

Furthermore, since the area of the intake/drain opening 274c is formed larger than the area of the outlet 274e, the intake/drain opening 274c is not filled with water that flows back through the outlet 274e, and the backflowing water is quickly discharged. This configuration reliably prevents water that flows back through the outlet 274e into the drain/vacuum breaker valve device 230 from flowing back into the upstream water supply control device 18. In addition, since the backflowing water can be quickly discharged from the drain valve hydraulic drive unit 14, the water remaining in the cylinder 14a is quickly discharged, and the flush water tank device can be quickly restored to its initial state.

On the other hand, when the intake/drain opening 274c of the drain/vacuum break valve device 230 is opened, outside air is sucked into the valve body case 272 through the upper part of the intake/drain opening 274c, as shown by the dashed arrow in FIG. 19. That is, since the intake/drain opening 274c is formed vertically long, water that has flowed back through the outlet 274e is discharged from the lower part of the intake/drain opening 274c, and at the same time, outside air can be easily introduced from the upper part of the intake/drain opening 274c. In this way, even if the water supply from the water supply control device 18 is stopped and the side of the inflow side water pipe attachment part 274a becomes negative pressure, outside air is sucked in from the drain/vacuum break valve device 230, so that the water that has flowed back from the inflow pipe 24a is prevented from flowing back into the water supply control device 18.

In this way, when the supply of water from the upstream side is stopped, the flap valve body 280 of the drain/vacuum breaker valve device 230 opens the upstream side to the atmosphere and simultaneously operates to drain backflowing water from the drain valve hydraulic drive unit 14. The drain/vacuum breaker valve device 230 has both the function of discharging backflowing water from the downstream side and the function of drawing outside air into the pipeline, and the intake/drain opening 274c functions as an intake port for outside air and a drain port for water in the pipeline.

According to the third embodiment of the flush water tank device of the present invention, the flap valve body 280 is supported by a shaft 281 oriented vertically, so that the flap valve body 280 can be rotated substantially without being affected by gravity.

Next, a flush water tank apparatus and a flush toilet apparatus equipped with the same according to a fourth embodiment of the present invention will be described with reference to Figures 22 and 23.
The flush water tank apparatus of this embodiment is equipped with a generator, and differs from the above-described first embodiment in that the solenoid valve of the water supply control device is operated by power generated by this generator. Therefore, only the configuration, action, and effects of the fourth embodiment of the present invention that differ from the first embodiment will be explained here, and similar configurations will be assigned the same reference numerals as in the first embodiment and explanations will be omitted.

Figure 22 is a front cross-sectional view showing the schematic configuration of a flush water tank device according to a fourth embodiment of the present invention. Figure 23 is a plan cross-sectional view showing the schematic configuration of a flush water tank device according to a fourth embodiment of the present invention.

As shown in Figures 22 and 23, the flush water tank device 304 according to the fourth embodiment of the present invention includes a generator 310 inside the water storage tank 10. The generator 310 includes a water wheel 310a and a power generation unit 310b. The water wheel 310a is configured to be rotated by the flow of water supplied to the generator 310. The power generation unit 310b is configured to generate electricity by the rotation of the water wheel 310a.

The power generated by the generator 310 is sent to the controller 28 and is configured to be stored in a storage battery (not shown) built into the controller 28. As a result, every time the flush water tank device 304 flushes the flush toilet body 2, water is supplied to the generator 310 to generate power, which is then stored in the storage battery (not shown). In the flush water tank device 304 of this embodiment, the controller 28 and the solenoid valve 20 of the water supply control device 18 are operated by the power generated by the generator 310 and stored in the storage battery (not shown). For this reason, the flush water tank device 304 can be installed in a toilet room where an external power source cannot be secured. Note that the control of the solenoid valve 20 of the water supply control device 18 by the controller 28 and the operation of the water supply control device 18 are the same as those in the first embodiment described above, and therefore will not be described.

As shown in Fig. 22, the generator 310 is attached to the upper end of the overflow pipe 10b so as to be located above the stop water level _L1 in the water storage tank 10. That is, since the generator 310 is located above the upper end opening of the upper end of the overflow pipe 10b, it will not be submerged even when the water level in the water storage tank 10 rises. Furthermore, in this embodiment, the generator 310 is located in the right region R of the left region L, the center region C, and the right region R, which are obtained by dividing the water storage tank 10 into three equal regions in the left-right direction X1 (Fig. 23) in a plan view. As shown in Fig. 23, in this embodiment, the generator 310 is located in the rear region, which is obtained by dividing the water storage tank 10 into two equal regions in the front-rear direction Y1 in a plan view.

Furthermore, in this embodiment, the water supply control device 18 and the drain/vacuum breaker valve device 30 are disposed in the left side region L, and the drain valve hydraulic drive unit 14 is disposed in the central region C. As shown in FIG. 23, in this embodiment, the drain valve hydraulic drive unit 14 is disposed approximately in the center of the water storage tank 10 in the front-to-rear direction in a plan view.

In this embodiment, the drain valve hydraulic drive unit 14 also includes an outer shell 314. This outer shell 314 is a frame-like member that supports the cylinder 14a and the like of the drain valve hydraulic drive unit 14 relative to the water storage tank 10, and the cylinder 14a is provided above the outer shell 314. Furthermore, as shown in FIG. 23, the outer shell 314 is disposed so as to surround the drain valve 12 in a plan view.

As shown in FIG. 22, the water supply control device 18 and the drain/vacuum break valve device 30 are connected by a water pipe 320, and the drain/vacuum break valve device 30 and the cylinder 14a are connected by a water pipe 322. Furthermore, the cylinder 14a and the generator 310 are connected by a water pipe 324, and a water pipe 326 is connected to the downstream side of the generator 310. The water pipe 326 extending from the generator 310 extends upward once, so that water remains around the water wheel 310a inside the generator 310 even after the supply of water to the generator 310 is stopped.

With this configuration, water supplied from the water supply control device 18 flows into the drain/vacuum break valve device 30 through the water pipe 320, and water flowing out of the drain/vacuum break valve device 30 flows into the cylinder 14a through the water pipe 322. Furthermore, water flowing out of the cylinder 14a flows into the generator 310 through the water pipe 324, and water flowing out of the generator 310 flows into the water storage tank 10 through the water pipe 326. That is, water that flows into the water pipe 326 from the generator 310 flows out from the outlet 326a at the end of the water pipe 326 and lands at the water landing position Q1 on the water surface in the water storage tank 10.

22, the water pipe 326 extends in a generally horizontal direction from the generator 310 disposed in the right region R of the water storage tank 10 to the outlet 326a disposed in the left region L, and the water landing position Q1 of the water W1 flowing out from the outlet 326a is also located in the left region L. Therefore, the generator 310 disposed in the right region R is disposed on the opposite side of the outer casing 314 of the drain valve hydraulic drive unit 14 from the water landing position Q1 located in the left region L. In other words, when the water storage tank 10 is divided into three equal parts in the left-right direction X1 in a plan view into the left region L, the center region C, and the right region R, the generator 310 is disposed in a region different from the region to which the water landing position Q1 belongs. As a modified example, the present invention can also be configured so that the generator 310 is disposed in the left region L and the water landing position Q1 is located in the right region R.

In this embodiment, the drain/vacuum break valve device 30 is also disposed in the left region L, so the water landing position Q2 of the water W2 drained from the intake/drain opening 74c of the drain/vacuum break valve device 30 is also disposed in the left region L. Therefore, the generator 310 disposed in the right region R is disposed on the opposite side of the outer casing 314 of the drain valve hydraulic drive unit 14 from the water landing position Q2 located in the left region L. In other words, when the water storage tank 10 is divided into three equal parts in the left-right direction X1 in a plan view into the left region L, the central region C, and the right region R, the generator 310 is disposed in a region different from the region to which the water landing position Q2 belongs. As a modified example, the present invention can also be configured so that the generator 310 is disposed in the left region L and the water landing position Q2 is located in the right region R.

23, the water landing position Q2 of the water W2 drained from the intake/drain opening 74c of the drain/vacuum breaker valve device 30 is located in the front region of the water storage tank 10, which is divided into two equal parts in the front-to-rear direction Y1 in a plan view. Therefore, the generator 310 arranged in the rear region of the water storage tank 10 is arranged on the opposite side of the outer casing 314 of the drain valve hydraulic drive unit 14 from the water landing position Q2, which is located in the front region. In other words, the generator 310 is arranged in a region different from the region to which the water landing position Q2 belongs when the water storage tank 10 is divided into two equal parts in the front-to-rear direction. As a modified example, the present invention can also be configured so that the generator 310 is arranged in the front region and the water landing position Q2 is located in the rear region.

According to the flush water tank apparatus 304 of the fourth embodiment of the present invention, the generator 310 is positioned above the stop water level _L1 in the water storage tank 10 (FIG. 22), and is positioned on the opposite side, in the left-right direction in a plan view, across the outer shell 314 from the water landing position Q2 where the water discharged from the drain/vacuum breaker valve apparatus 30 lands on the water surface in the water storage tank 10. As a result, the water that flows out from the drain/vacuum breaker valve apparatus 30 lands on the water surface in the water storage tank 10 is blocked by the outer shell 314, so it is possible to prevent the generator 310 from becoming wet.

In addition, according to the flush water tank device 304 of this embodiment, the generator 310 is disposed in an area of the left area L, the center area C, and the right area R in a plan view that is different from the area to which the water landing position Q2 belongs (FIG. 22), so that a relatively large distance can be secured between the water landing position Q2 and the generator 310. This effectively prevents the water flowing out of the drain/vacuum breaker valve device 30 from landing on the water surface in the water storage tank 10 and splashing water from getting onto the generator 310.

Furthermore, according to the flush water tank device 304 of this embodiment, the landing position Q2 of the water flowing out from the drain/vacuum break valve device 30 is located in the left area L of the water storage tank 10, whereas the generator 310 is located in the right area R (Figure 22). Therefore, a relatively large distance can be secured between the landing position Q2 in the water storage tank 10 and the generator 310, and the water flowing out from the drain/vacuum break valve device 30 can be effectively prevented from landing on the water surface in the water storage tank 10 and splashing onto the generator 310.

In addition, according to the flush water tank device 304 of this embodiment, the generator 310 is positioned on the opposite side of the outer casing 314 in the front-to-rear direction from the landing position Q2 of the water flowing out of the drain/vacuum breaker valve device 30 (Figure 23), so that the water that flows out of the drain/vacuum breaker valve device 30 lands at the landing position Q2 and splashes can be blocked by the outer casing 314, effectively preventing the generator 310 from becoming wet.

Furthermore, according to the flush water tank device 304 of this embodiment, the cylinder 14a of the drain valve hydraulic drive unit 14 is provided above the outer shell 314 (Figure 22), so that the water that flows out of the drain/vacuum breaker valve device 30 lands at the water landing position Q2 and splashes can also be blocked by the cylinder 14a, making it possible to more effectively prevent the generator 310 from becoming wet.

The flush water tank device and the flush toilet device equipped with the same according to the embodiment of the present invention have been described above, but various modifications can be made to the above-described embodiment. In particular, in the above-described embodiment, the drain/vacuum breaker valve device is equipped with a flap-type valve body, but any type of valve body can be applied, such as a direct-acting valve body.

1 Flush toilet device 2 Flush toilet body (flush toilet)
Reference Signs List 2a Bowl section 4 Flush water tank device 6 Remote control device 8 Human presence sensor 10 Water storage tank 10a Drain port 10b Overflow pipe 12 Drain valve 12a Valve shaft 12b Valve body section 12c Engagement protrusion 12d Support section 14 Drain valve hydraulic drive section 14a Cylinder 14b Piston 14c Spring 14d Gap 14e Packing (elastic member)
14f Sleeve 14g Outflow guide portion 15 Rod (driving member)
15a Thin wall part 15b Pulling part 15c Upper surface 15d Abutted part 16a Pressure chamber 16b Back pressure chamber 17 Communication channel 17a Upper end opening (back pressure chamber opening)
17b Side opening (rod opening)
17c Edge portion 18 Water supply control device 20 Solenoid valve 22 Clutch mechanism 24a Inlet pipe 24b Outlet pipe 24c Outlet pipe branch portion 24d Orifice (flow rate suppression means)
25a inlet 25b outlet 26 drain valve float mechanism (float mechanism)
26a Float part (float)
26b Engagement portion 26c Float shaft 28 Controller 30 Drain/vacuum breaker valve device 32 Water supply pipe 32a Stopcock 32b Constant flow valve 34 Water supply valve float 36 Main body 36a Pressure chamber 38 Main valve body 40 Valve seat 42 Arm portion 44 Float side Pilot valve 50 Solenoid valve side pilot valve 60 Movable member 62 Base plate 64 Arm 66 Rotating shaft 68 Contact portion 70 Restricting portion 72 Valve body case 74 Main body portion 74a Opening 74b Mounting portion 74c Intake/drain opening 74d Upper edge 74e Lower edge 76 Inflow pipe connecting member 76a Water pipe mounting portion 76b Bearing portion 76c Inflow port 78 Outflow pipe connecting member 78a Water pipe attachment portion 78b Outlet 80 Flap valve body (valve body)
80a Support shaft (center axis)
80b Supply water receiving portion 80c Valve plate portion 80d Drainage receiving portion 80e Weight attachment portion 82 Gasket 82a Weight 84 Coil spring (biasing spring)
90 Negative pressure release valve 92 Negative pressure release valve body 94 Atmospheric opening 96a Main valve port 96b Main valve body 98 Outlet 130 Drain/vacuum release valve device 172 Valve body case 174 Body portion 174a Upper mounting portion 174b Lower mounting portion 174c Intake/ Drain opening 174d Upper edge 174e Lower edge 176 Cover member 176a Bearing portion 177 Inflow pipe connecting member 177a Water pipe mounting portion 177b Inflow port 178 Outflow pipe connecting member 178a Water pipe mounting portion 178b Outflow port 180 Flap valve body 180a Support shaft 180b Valve plate Part 180c Drain receiving part 180d Weight attachment part 182 Gasket 182a Weight 230 Drain/vacuum break valve device 272 Valve body case 274 Main body 274a Inlet water pipe mounting portion 274b Outlet water pipe mounting portion 274c Intake/drain opening 274d Inlet 274e Outlet 276 Lid member 278 Cover 280 Flap valve body 280a First flat plate portion 280b Second flat plate portion 280c Connection portion 281 Shaft 282, packing 283, small packing 284, torsion coil spring 304, flushing water tank device 310, generator 310a, water wheel 310b, power generating section 314, outer shell section 320, water pipe 322, water pipe 324, water pipe 326, water pipe 326a, outlet

Claims (19)

A flush water tank device that supplies flush water to a flush toilet,
a water storage tank for storing flush water to be supplied to the flush toilet and having a drain port for discharging the stored flush water into the flush toilet;
a drain valve that opens and closes the drain outlet and starts and stops the supply of flush water to the flush toilet;
a drain valve water pressure drive unit that drives the drain valve by utilizing the water supply pressure of the supplied water;
a drain/vacuum breaker valve device that is provided upstream of the drain valve hydraulic drive unit and supplies water supplied from the upstream side to the drain valve hydraulic drive unit downstream,
The drain valve hydraulic drive unit is
a cylinder into which water is fed through said drain/vacuum break valve arrangement;
a piston slidably disposed within the cylinder and moved by the pressure of water flowing into the cylinder to move the drain valve;
the drain/vacuum breaker valve device is provided with a valve body that operates to open the upstream side to the atmosphere and drain backflowing water from the drain valve water pressure drive unit when the supply of water from the upstream side is stopped ,
The flush water tank apparatus is characterized in that the drain/vacuum breaker valve device comprises an inlet for allowing supplied water to flow in, an outlet for supplying the inflowing water to the drain valve water pressure drive unit, and an air intake/drain opening that is opened and closed by the valve body, the inlet being provided above the outlet, and the air intake/drain opening being formed on a vertical surface or an inclined surface . 2. The flush water tank assembly of claim 1 , wherein the area of said intake/drain opening of said drain/vacuum break valve assembly is greater than the area of said outlet of said drain/vacuum break valve assembly. 3. A flush water tank apparatus according to claim 1, wherein the intake/drain opening of the drain/vacuum breaker valve device is formed to be longer in the vertical direction than in the horizontal direction. 4. A flush water tank apparatus as claimed in any one of claims 1 to 3, wherein the valve body of the drain/vacuum break valve device is provided rotatably about a predetermined central axis, and opens and closes the intake/drain opening by being rotated. 5. A flush water tank apparatus according to claim 4 , wherein said predetermined central axis is disposed outside a vertical projection plane of said intake/drain opening. A flush water tank apparatus as described in any one of claims 1 to 5, wherein the air intake/drain opening is formed so that its lower edge extends horizontally, and water that flows back from the drain valve water pressure drive unit to the drain/vacuum breaker valve device passes over the lower edge and is discharged into the water storage tank. 7. A flush water tank apparatus according to claim 6 , wherein the air intake/drain opening is formed so that its upper edge extends horizontally. A flush water tank apparatus as described in any one of claims 1 to 7, wherein the valve body is in a standby position in which the center of gravity of the valve body is at its lowest when water is not supplied to the drain/vacuum break valve device. 9. The flush water tank apparatus according to claim 8 , wherein the valve body is provided with a weight. 10. A flush water tank assembly according to claim 1, wherein the drain/vacuum break valve assembly includes a biasing spring which biases the valve body in a direction that opens the intake/drain opening. 11. The flush water tank apparatus according to claim 10 , wherein the biasing spring is configured such that the increment of the biasing force relative to the increment of the deformation increases as the amount of deformation increases. 11. A flush water tank apparatus according to claim 10 , wherein the biasing spring is configured so as not to apply a biasing force to the valve body when the intake/drain opening is open to a predetermined amount or more. 13. A flush water tank apparatus according to claim 1, further comprising flow rate suppression means for suppressing the flow rate of water flowing back from the drain valve water pressure drive portion to the drain/vacuum breaker valve device. A flush water tank device that supplies flush water to a flush toilet,
a water storage tank for storing flush water to be supplied to the flush toilet and having a drain port for discharging the stored flush water into the flush toilet;
a drain valve that opens and closes the drain outlet and starts and stops the supply of flush water to the flush toilet;
a drain valve water pressure drive unit that drives the drain valve by utilizing the water supply pressure of the supplied water;
a drain/vacuum breaker valve device that is provided upstream of the drain valve hydraulic drive unit and supplies water supplied from the upstream side to the drain valve hydraulic drive unit downstream,
The drain valve hydraulic drive unit is
a cylinder into which water is fed through said drain/vacuum break valve arrangement;
a piston slidably disposed within the cylinder and moved by the pressure of water flowing into the cylinder to move the drain valve;
a generator including a water wheel rotated by the flow of the supplied water and a power generation unit that generates electricity by the rotation of the water wheel;
a water supply control device that is provided with an electromagnetic valve that is operated by the power generated by the generator and controls the start and stop of water supply to the drain/vacuum breaker valve device,
the drain/vacuum breaker valve device is provided with a valve body that operates to open the upstream side to the atmosphere and drain backflowing water from the drain valve water pressure drive unit when the supply of water from the upstream side is stopped,
The drain valve hydraulic drive unit has an outer casing arranged to surround at least a portion of the drain valve in a planar view, and the generator is arranged above the stop water level in the water storage tank and is arranged on the opposite side of the outer casing in the left-right direction in a planar view from the water landing position where water drained from the drain/vacuum breaker valve device lands on the water surface in the water storage tank. A flush water tank device as described in claim 14, wherein the generator is arranged in an area other than the area to which the water landing position belongs when the water storage tank is divided into three equal parts in a left area, a central area, and a right area in a left - right direction when viewed in a plane. A flush water tank apparatus as described in claim 15, wherein the water landing position is located in either the left side area or the right side area of the water tank when viewed in a plan view, and the generator is positioned in the other of the left side area or the right side area of the water tank when viewed in a plan view. 17. A flush water tank apparatus according to any one of claims 14 to 16, wherein the generator is arranged on the opposite side of the water landing position in the front-to-rear direction, sandwiching the outer casing of the drain valve water pressure drive unit therebetween. 18. A flush water tank apparatus according to any one of claims 14 to 17 , wherein the cylinder of the drain valve hydraulic drive section is provided above the outer shell section. A flush toilet device comprising:
A flush water tank apparatus according to any one of claims 1 to 18 ;
the flush toilet that is flushed with flush water supplied from this flush water tank device;
A flush toilet device comprising:

Images