JPH033101B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an air intake device (also referred to as a vacuum breaker or vacuum breaker valve) for a water supply pipe, which is installed in a water supply pipe such as a water supply pipe, and allows atmospheric air to be introduced when the inside of the pipe becomes negative pressure. ).

Jikosho developed this device to introduce atmospheric air to destroy the vacuum inside the pipe when the pressure inside the water supply pipe becomes negative due to a water outage.
A vacuum breaker valve as disclosed in Japanese Patent No. 50-27001 is known. As shown in FIG. 5, this device forms a cylindrical part b on the peripheral wall of a water supply pipe a, and fits into the cylindrical part a lid d formed around a ventilation hole c. A valve body g formed in a rubber cap-like body f is opposed to a valve seat e at the inner end, and when the inside of the water supply pipe a becomes negative pressure, the valve body g separates from the valve seat e and opens the ventilation hole. However, due to the small diameter of the vent hole c, if the vacuum suction speed that occurs at the water supply source during a water outage is fast, the amount of air that can be sucked through the vent hole c will be insufficient. Since the negative pressure in the passage could not be compensated immediately, there was a risk that backflow would occur and wastewater would be sucked up from the secondary side. In that case, the diameter of vent c should be made sufficiently large, but in order to solve this problem, the diameter of vent c should be made much larger than the diameter of water supply pipe a, so doing so would cause the equipment to become very unstable. This had the disadvantage of increasing the size.

The present invention has been made in view of the above-mentioned problems, and an object of the present invention is to provide a device that is small in size but can reliably break the vacuum and reliably prevent backflow of water. In order to achieve this purpose, the water supply pipe intake device of the present invention opens the water passage port widely for forward flow, and provides slight communication between the primary side and the secondary side through a small flow gap even for reverse flow. A semi-closed check valve is connected to the water supply pipe, and a vent wider than the flow gap is opened on the secondary side of the check valve, and the water supply pipe is under negative pressure. The system is equipped with an intake valve that introduces atmospheric air when water is cut off, and even if the check valve is closed during a water outage, the primary and secondary sides of the water supply pipe are slightly connected through the flow gap. Even if the vacuum suction speed on the primary side is high, the vacuum can be broken without causing backflow of water.

An embodiment of the present invention will be described below with reference to FIGS. 1 to 4. In the figure, 1 is a valve body formed in a substantially bifurcated shape, 2 is a union nut fixed to one end of the valve body with an engagement ring 3 for connection to a water supply source, and 4 is a washing machine to which water is supplied. Valve body 1 for connecting to a hose or shower hose
Connect this valve body 1 with the connection port formed on the other end.
A vent plug body 7 formed around the vent 6 is airtightly screwed onto the valve body 1 with a packing 8 interposed so that the vent 6 is located on the same axis as the water inlet 5 inside. . Reference numeral 9 denotes an air permeable lid that covers the outer end of the ventilation plug body 7. A cylindrical portion 10 of the ventilation plug body 7 having a ventilation hole 6 formed at its tip is provided in a protruding manner within the valve body 1. Reference numeral 11 designates a check valve having a dish-like shape and having a groove-shaped flow gap 12 formed on the surface facing the water inlet 5. The check valve allows the inside of the valve body 1 to be connected to the primary side 13 and the secondary side. 1
It is divided into 4. Reference numeral 15 denotes an intake valve that is in airtight contact with the vent 6. As shown in FIG. By slidingly contacting the cylindrical inner wall surface of the intake valve 1, the intake valve 15 can slide without tilting and come into close contact with the ventilation port 6.
Further, the check valve 11 is surrounded by the inner peripheral edge of the guide vane 16 so as to be slidable therein, and a relatively weak elastic coil spring 17 is installed between the intake valve 15 and the check valve 11. The intake valve 15 and the check valve 11 are interposed in a suitably compressed state and are brought into light contact with the ventilation port 6 and the water passage port 5, respectively.

The intake valve for a water supply pipe configured in this way is used by connecting the union nut 2 to a water supply source such as a water supply pipe or hot water supply of a boiler, and connecting the connection port 4 to, for example, a flexible shower hose. When water is supplied from the water supply source, the pressure of the water supply pushes up the check valve 11 as shown in FIG. The water flowing into the next side 14 passes through the connection port 4 and is supplied to a shower hose or the like. If the water supply source is cut off, the check valve 11 closes the water inlet 5 due to the elasticity of the coil spring 17, but the primary side 13 and the secondary side 14 are still in communication with each other through the flow gap 12. Therefore, the negative pressure on the primary side 13 gradually propagates to the secondary side 14 through the flow gap 12, and while the primary side 13 suddenly becomes a large negative pressure, the secondary side 14 gradually becomes negative pressure. . If the secondary side 14 becomes even slightly negative pressure, the intake valve 15 is opened and atmospheric air is introduced through the vent 6 which is wider than the flow gap 12. Therefore, even if the end of the shower hose connected to the connection port 4 is immersed in the bathtub, a negative pressure that can suck up the hot water in the bathtub will not be generated on the secondary side 14. Further, the vacuum in the primary side 13 is also destroyed by the air flowing in from the vent 6 into the primary side 13 through the flow gap 12. Note that by opening the water inlet 5 and the vent 6 on the same axis of the valve body 1 and interposing the coil spring 17 between the check valve 11 and the intake valve 15, the structure can be simplified and a single unit can be used. Both valves can be controlled by the coil spring 17, and the compression force of the coil spring 17 increases during water supply, so that the intake valve 1
5 more airtightly closes the vent 6, so reliable operation can be expected without fear of water leakage. In addition, as described above, in the device of the present invention, the primary side 13 and secondary side 14 of the check valve 11 are always kept in a state of communication, albeit slightly, so a drain plug (not shown) for preventing freezing is provided on the primary side. ), water in a shower hose attached to a hanger at a high position can be drained from the drain plug by operating the drain plug.

As explained above, the water supply pipe intake device of the present invention uses a semi-closed check valve to allow negative pressure on the primary side to propagate to the secondary side through a small flow gap during water outage. To prevent backflow of sewage, etc. without causing excessive negative pressure on the secondary side even if a vent for introducing the atmosphere is smaller than the diameter of a water supply pipe.
Therefore, the present invention has the advantageous effect of being able to realize the vacuum breaking function in a compact and reliable manner.

[Brief explanation of the drawing]

FIG. 1 is a longitudinal sectional view showing an embodiment of the present invention;
Figure 2 is a perspective view of the vent valve, check valve, and coil spring, Figures 3 and 4 are longitudinal sectional views showing the operating state of Figure 1, and Figure 5 is a longitudinal sectional view of a conventional vacuum breaker valve. It is a diagram. 1...Valve body, 5...Water port, 6...Vent hole, 11...Check valve, 12...Flow gap, 13
...Primary side, 14...Secondary side, 15...Intake valve,
17...Coil spring.

Claims (1)

[Scope of Claims] 1. A semi-closed inverter that opens the water port widely for forward flow and slightly communicates the primary and secondary sides through a small flow gap even for reverse flow. A stop valve is provided in the water supply pipe, and a vent wider than the flow gap is opened on the secondary side of the check valve, and air is introduced into the vent when the water supply pipe becomes negative pressure. An intake device for a water supply pipe characterized by being equipped with a valve. 2. A water inlet and a vent are opened on the same axis of the vibe body, and a coil spring is appropriately compressed and interposed between a check valve and an intake valve corresponding to the water inlet and the vent, respectively. An air intake device for a water supply pipe according to claim 1.