JPS591359B2 - tankless pump - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a so-called tankless pump having no pressure tank.

Conventionally, Wesco pumps and Hugal jet pumps used in wells, etc. are generally equipped with a pressure tank, and the compressed air pressure in this pressure tank is used to operate a pressure switch and automate the drive of the pump. was.

In such pumps, when the air in the pressure tank decreases, the pressure switch opens and closes frequently, which may cause premature burnout of the switch and adversely affect the pump and tank. In addition, an air replenishment device is required and expensive, and the large capacity pressure tank and air replenishment device are bulky, making handling inconvenient and requiring a large installation area.

Furthermore, even when using a fixed amount, the pressure switch opens and closes at regular intervals and the pump operates intermittently, so the water pressure is not constant and the amount of water is also changing, and when using a water heater etc., the water temperature is not constant. It also had drawbacks.

Therefore, in recent years, progress has been made in the development of so-called tankless pumps in which the pressure tank is significantly downsized or the pressure tank is eliminated, and the drive of the pump is automated in the same way as in the case with a pressure tank.

For example, in the case of a Wesco pump, if there is no pressure tank,
When a small amount of water less than the rated water amount is discharged with the faucet in a half-open state, the pressure in the discharge channel system immediately rises above 0FFFF of the pressure switch, and the pressure switch opens and closes extremely frequently.

Therefore, a bypass waterway equipped with an IJ valve is used to connect the pump's discharge side and suction side, and when the amount of water used is small, excess water is returned to the pump's suction side to suppress pressure rise. There is.

Even in such a bypass type tankless pump, when the amount of water used becomes a certain amount, the pressure of the discharge channel system is set to be above 0FFFF of the pressure switch, so if a small amount of water is continuously discharged and used. , the pressure switch will open and close frequently.

In addition, in order to prevent the frequent opening and closing of the pressure switch that occurs when using a small amount of water, a timer is connected in parallel with the pressure switch to continue operating the pump for a while after the pressure switch is opened, thereby delaying the actual opening. However, when using a small amount of water, the pump operation time is slightly extended due to the delay timer, but the pressure switch still opens and closes repeatedly.

Therefore, in the case of a tankless pump, in order to eliminate fluctuations in water supply pressure and to operate automatically, the opening and closing of the switch must be controlled so that the pump operates continuously while discharging water, regardless of the amount of water used. There is a need.

The present invention has been made as a result of various studies in view of the above points, and has resulted in the invention of a tankless pump that can reliably control the opening/closing action of the switch, that is, the operation of the pump, based on both the pressure on the discharge side and the flow rate of the discharge waterway. It is something that

That is, the present invention utilizes a diaphragm mechanism that extracts the differential pressure of a fluid through a variable throttle valve or the like provided in a discharge waterway and performs a displacement action based on the change in the pressure difference, and a piston mechanism that performs an advancing and retracting action based on pressure fluctuations on the discharge side. The diaphragm mechanism and the piston mechanism are positioned so that the direction of displacement of the diaphragm intersects the direction of movement of the piston, and a movable cam for operating a switch connected to the motor is disposed at the intersecting position. The cam is connected to both the diaphragm and the piston, and the movable cam cooperates with the displacement action of the diaphragm and the movement forward/backward action of the piston, thereby reliably opening and closing the switch.

Next, embodiments of the present invention will be described with reference to the drawings.

P is a Wesco pump, 1 is a water suction pipe from a well, etc., and 2 is a discharge waterway.

3 is a bypass water passage for water return that connects the discharge side and suction side of the pump P, and 4 is a relief valve.

Reference numeral 5 designates an orifice-type variable restrictor valve installed at an appropriate location in the discharge waterway 2, and there is a pressure difference between the upstream and downstream sides of the valve when the flow rate exceeds a certain amount, which is as small as a water leak; This is so that the differential pressure disappears.

Instead of the variable throttle valve 5, a normal resistance valve or the like can be provided in the discharge waterway 2 to generate a pressure difference (not shown).

Reference numeral 6 denotes a diaphragm mechanism provided separately from the above, and this diaphragm mechanism 6 has one of the water inflow chambers 61 and 62 partitioned by the diaphragm 60 on the upstream side of the variable throttle valve 5, and the other on the downstream side. They are connected to each other through communication pipes 63 and 64, and the differential pressure of the fluid caused by the variable throttle valve 5 is expanded and taken out by a diaphragm 60 having a large pressure receiving area, and the diaphragm 60 performs a displacement action in accordance with the differential pressure. It is set up.

In particular, the water inflow chamber 61 on the low pressure side is equipped with a spring 65 that presses the diaphragm 60 toward the high pressure side, and when there is a differential pressure, the diaphragm 60 is displaced toward the low pressure side against the spring 65, creating a differential pressure. When the pressure is exhausted, the spring 65 allows the pressure to be displaced toward the high pressure side, thereby improving the displacement effect of the diaphragm 60.

7 is a piston mechanism, which connects one end side of a cylinder 71 containing a piston 70 to the pump discharge side, that is, a part of the discharge waterway 2 through a communication pipe 72, so that water can flow into the cylinder 71; A spring 73 that presses the piston 70 toward the water inflow side is provided on the other end side within the spring 71.
The piston 70 is equipped with a force relationship between the inflow water pressure and the pressing force of the spring 73 so that the piston 70 moves forward and backward as the inflow water pressure changes, and the inflow water pressure is 0FFFF.
In the upper and lower ONN pressure states, the piston 70 is located at relative positions close to both ends of the cylinder 71, that is, at a position with a large amount of inflow water and a position with a small amount of inflow water.

The diaphragm mechanism 6 and the piston mechanism 7 are positioned so that the direction of displacement of the diaphragm 60 and the direction of movement of the piston 70 intersect at right angles.

That is, a connecting rod 66 is connected to the center of the diaphragm 60 at right angles to the pressure receiving surface and protrudes outside the water inlet chamber 62 on the high pressure side.
The extension of the connecting rod 74 connected to the piston 70 intersects with the extension of the connecting rod 74.

Reference numeral 8 denotes a movable cam for opening/closing operations for a switch 9 such as a microswitch, and is arranged at the above-mentioned intersecting position.

The movable cam 8 is connected to the diaphragm 60 by a connecting rod 66, and is also connected to the piston 70 by fitting into the movable frame 10 connected to the connecting rod 74 of the piston 70 so as to be slidable in the direction of displacement of the diaphragm. Due to the displacement action of the diaphragm 60, the diaphragm moves in the diaphragm displacement direction independently of the movable frame 10, and at the same time, the piston 7
It is provided so that it can move integrally with the movable frame 10 in the direction of piston movement perpendicular to the above-mentioned movement due to the movement of the piston.

In this embodiment, the connecting rod 6 on the diaphragm 60 side
A pin joint structure 67 is formed in the middle of the movable cam 6 so that it can be bent, and a pin joint structure 68 is also used to connect the movable cam 8 and the connecting rod 66 so that the movable cam 8 can be moved in the piston forward and backward direction without any trouble. I try to do that.

Further, the movable cam 8 has a cam surface 80 on the side opposite to the side connected to the diaphragm 60, and this cam surface 80 is formed into two stages of a convex portion 81 and a concave portion 82.

On this cam surface 80, an active end 91 of an opening/closing lever 90, which is connected to a switch 9 connected to a motor for driving the pump, is attached.
The switch 9 is opened and closed by pressing and releasing the opening/closing lever 90 with the movable cam 8.

The switch 9 is a normally closed switch that opens when a switch button 92 is pressed by an open/close lever 90 and closes when it is not pressed.

Therefore, the positional relationship between the movable cam 8 and the working end 91 of the opening/closing lever 90 is such that when the inflow water pressure in the piston mechanism 7 is low, the recess 82 of the cam surface 80 is in contact with the working end 91; When the convex part 81 of the cam surface 80 is in a position where it comes into contact with the working end 9H, and when the diaphragm 60 of the diaphragm mechanism 6 is displaced toward the low pressure side due to the differential pressure, the convex part 81 and the concave part of the cam surface 80 are in contact with the working end 9H. No matter which of the movable cams 82 is in the position where it comes into contact with the working end 91, the movable cam 8
When the opening/closing lever 90 cannot be suppressed and the differential pressure disappears and the diaphragm 60 becomes non-displaced or is displaced to the high pressure side, if the convex portion 81 of the cam surface 80 is in a position where it comes into contact with the working end 91. , opening/closing lever 90 with movable cam 8
It is set up so that it can be suppressed.

Note that a roller is provided at the working end 91 in order to smoothly move the movable cam 8.

In addition, in the piston mechanism 7, as a spring 73 that presses the piston 70 toward the water inflow side, as shown in FIG.
It can be provided so as to press the entire movable frame 10 connected to the piston 70.

Furthermore, the movable cam 8 is connected to the diaphragm 60 and the piston 70 by making the connecting rod on the piston 70 side bendable and rotatably connecting the movable cam 8 to this connecting rod using a pin joint or the like. At the same time, it is also possible to connect a movable frame to the connecting rod on the diaphragm 60 side and fit the movable cam 8 thereto so that it can slide in the direction of movement of the piston. It is also possible to make both of the connecting rods bendable and to connect the movable cams 8 to both connecting rods by pin joints.

Of course, configurations other than those described above may be used as long as the movable cam 8 is configured to cooperate with the displacement action of the diaphragm 60 and the movement of the piston 70 in mutually intersecting directions.

The present invention is constructed as described above, and as shown in Fig. 1, an accumulator A having a capacity of about 30''-100 compared to a conventional pressure tank is provided, and a very small amount of water, equivalent to a leak, is allowed to flow. This prevents the pump P from operating immediately.

Next, the present invention will be explained in detail.

First, when the pump P is installed and started, water is not flowing into the discharge channel 2 and water is not flowing into the water inflow chambers 61 and 62 of the diaphragm mechanism 6.
The diaphragm 60 is in an undisplaced position or in a position displaced toward the high pressure side by the spring 65, and the movable cam 8 connected to the diaphragm 60 is in a position where it can press the opening/closing lever 90 of the switch 9, but it is in communication with the discharge waterway 2. Since no water is flowing into the piston mechanism 7 that has been installed, and the inflow water pressure cannot be sensed, the piston 70 is connected to the spring 7.
2, the movable cam 8 moves together with the inflow water at a small amount position. Do not press the lever 90 (Fig. 3)
, the switch 9 is closed and the pump P can be operated.

When water flows into the discharge channel 2, water also flows into the water inlet chambers 61, 62 in the diaphragm mechanism 6 and the cylinder 71 in the piston mechanism 7. However, if the faucet 10 is fully opened, the discharge A water inlet chamber 6 where the flow rate of the water channel 2 is high and communicates with the upstream side of the variable throttle valve 5, etc.
Naturally, there is a difference in pressure between 2 and the water inlet chamber 61 communicating with the downstream side, and this pressure difference causes the diaphragm 60 to be displaced toward the low pressure side, and the movable cam 8 cooperates with this displacement action, making it impossible to press the opening/closing lever 90. It will move away from the position.

Moreover, at this time, the inflow water pressure in the piston mechanism 7 has not increased significantly, the piston 70 is still in the small amount of inflow water position, and the movable cam 8 has a concave portion 82 in the cam surface 80 connected to the operating end 90 of the opening/closing lever 90. The operation of the pump P continues without pressing the opening/closing lever 90.

Next, when the faucet 10 is closed and a small amount of water exceeding a certain minimum amount is used, the pressure in the discharge channel 2, that is, the piston mechanism 7
The inflow water pressure increases, and with this pressure increase, the piston 70 moves against the spring 72 to a position with a large amount of inflow water, and the movable cam 8 moves together with this, and the convex part 81 is located at a position corresponding to the operating end 91 of the opening/closing lever 90. However, even if the flow rate of the discharge waterway 2 is small, the water flow of the diaphragm mechanism 6 communicating with the upstream and downstream sides of the variable throttle valve 5 There is a difference in the pressure of entry 61.62,
Similar to when the faucet is fully open, the diaphragm 60 still maintains its displaced state, and the movable cam 8 cannot press the opening/closing lever 90 even though the convex portion 81 and the working end 91 correspond and are in contact with each other. The pump P will be operated continuously as shown in FIG. 4.

The pressure increase at this time is limited by the relief valve 4.

Furthermore, when the faucet 10 is closed from the above case and the flow rate of the discharge waterway 2 is reduced to zero or below a certain amount of water that is as small as a water leak, the differential pressure between the upstream side and the downstream side of the variable throttle valve 5 etc., that is, the diaphragm. Since the differential pressure in the water inlet chambers 61, 62 of the mechanism 6 will disappear, the diaphragm 60 will
The movable cam 8 moves and contacts the convex portion 81 of the cam surface 80. When the active end 91 of the lever 90 is pressed (FIG. 5), this suppressing action opens the switch 9 and stops the pump P.

During this period, if a very small amount of water continues to flow out, such as water leakage, it is done by the accumulator A. When the accumulator A stops working, the inflow water pressure in the discharge channel 2 and the piston mechanism 7 becomes low pressure, and the piston 70 moves to the small inflow water position due to the pressing force of the spring 73, and the movable cam 8 that moves together with this moves so that the recess 82 of the cam surface 80 corresponds to the active end 91 of the opening/closing lever 90, and the movable cam 8 The pressure on the opening/closing lever 90 is released, and the pump P starts operating again.

When accumulator A becomes full of water, discharge channel 2
The water pressure and the inflow water pressure in the piston mechanism 7 rise, and the movable cam 8 cooperates with the movement of the piston 70 to the large amount of inflow water position to open the switch 9 and stop the operation of the pump P. It is something that makes you

Pump P operates automatically in this way.

Note that the present invention can be similarly implemented in a Hugal jet pump, but in this case, a bypass waterway is unnecessary.

As described above, the present invention is equipped with a diaphragm mechanism that extracts the differential pressure of fluid through a variable throttle valve or the like provided in the discharge waterway and performs a displacement action based on the change in differential pressure. It can be enlarged and taken out by action,
Moreover, by utilizing the fact that the pressure difference disappears when the flow rate becomes less than a certain minimum amount of water, it is possible to reliably detect whether the flow rate in the discharge channel is above or below a certain amount of extremely small amount of water.

Furthermore, since a piston mechanism is provided that moves forward and backward in response to pressure fluctuations on the discharge side, the pressure on the discharge side can also be reliably detected by the movement of the piston back and forth.

The diaphragm mechanism and the piston mechanism are positioned so that the direction of displacement of the diaphragm and the direction of movement of the piston intersect, and one movable cam for operation disposed at the crossing position is used to effect the movement of the diaphragm and the movement of the piston. Since the switch connected to the motor is operated in conjunction with the action, the cam shape of this movable cam is formed so that each movement in the above-mentioned cross directions is adapted to the opening and closing control of the switch. If the flow rate exceeds a very small constant amount of water, the displacement action of the diaphragm will allow the movable cam to be kept in the closed state regardless of pressure fluctuations, with the movable cam in a position where it does not act on the switch. In addition, when the flow rate becomes less than the above-mentioned certain amount of water, the displacement action of the diaphragm is canceled and the movable cam is moved in the direction of the above-mentioned diaphragm displacement by the movement of the piston back and forth due to pressure fluctuations on the discharge side. can be moved crosswise to open the switch.

In this way, the opening and closing of the switch can be reliably controlled by both flow rate and pressure, and when using a small amount of water, the switch will not open and close intermittently, preventing burnout of the switch and extending its life. This is something that can be extended over a long period of time.

- As mentioned above, the present invention is extremely suitable for use as a tankless pump such as a Wesco pump or a Hugal jet pump, and has a good control action and can significantly reduce the frequency of opening and closing switches, and has a simple structure. It has excellent effects such as being compact and lightweight, making it easy to handle during transportation, etc., and helping to reduce the installation area of the pump, which can promote cost reduction.

[Brief explanation of drawings]

FIG. 1 is an overall water map showing an embodiment of the present invention, FIG. 2 is a water map showing another embodiment, and FIGS. 3 to 5 are water charts showing operating states. P...Pump, 2...Discharge waterway, 5.
...Variable throttle valve, 6...Diaphragm mechanism, 60...Diaphragm, 7...Piston mechanism, 70...Piston, 8... ...
・Movable cam, 9... Switch, 90...
・Opening/closing lever.

Claims (1)

[Claims] 1 Equipped with a diaphragm mechanism that extracts the differential pressure of the fluid by a variable throttle valve etc. installed in the discharge waterway and performs a displacement action based on the change in pressure difference, and a piston mechanism that performs a forward and backward action according to pressure fluctuations on the discharge side. The diaphragm mechanism and the piston mechanism are positioned so that the direction of displacement of the diaphragm and the direction of movement of the piston intersect, and a movable cam for operating a switch connected to the motor is disposed at the intersecting position, and the movable cam is By connecting both the diaphragm and the piston, and making the movable cam work together with the movement of the diaphragm and the movement of the piston,
A tankless pump characterized in that the switch is configured to open and close.