JPH087456Y2 - Pressure reducing valve with water stop device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a pressure reducing valve provided with a water stop device.

Conventionally, a pressure reducing valve is generally used in a high-pressure area for the purpose of preventing damage to piping equipment due to a water hammer, and in a place where a hot water supply equipment such as a boiler is used, a pressure reducing valve is generally used to protect a can. Since all of them do not have a water stop device, a water stop device such as a water stop valve or a stop valve was inevitably required upstream of the pressure reducing valve in order to replace the packing of the faucet. As an exception, in cold region pressure reducing valves, it is also proposed that the pressure reducing valve incorporates a water stop and drainage device, as disclosed in JP-B-58-45346 by the same applicant. Since it is necessary to connect the operation rod and the like, there is a defect that the size is inevitably increased and the structure is complicated. Therefore, the present invention has been proposed for the purpose of providing a small-sized pressure reducing valve with a water shut-off device having a very simple structure, and a specific configuration for achieving the above object is as follows.

That is, it has an inflow port below the side wall and an outflow port above.
An upward valve seat is provided in the middle part, and an annular packing that slides on the cylinder and a water blocking packing that closes the valve seat are installed inside a valve box that has a cylinder coaxial with the valve seat below the inlet. The mounted piston moves up and down due to the upward pressing force of the spring housed in the spring chamber formed at the lower end of the piston and the downward secondary pressure of the secondary pressure chamber that is located above the valve seat and adjacent to the outlet. In addition to moving it to provide a pressure reducing function, position the operating rod above the piston separately from the piston, lower the operating rod with a screw, etc., and bring the water-stop packing into close contact with the valve seat to stop water. It was done like this.

The present invention will be described below with reference to the embodiments shown in the drawings.

FIG. 1 mainly shows an embodiment of a pressure reducing valve housed in a meter box in the ground. In the figure, 1 is a valve box, and an inlet 2 is located below the side wall and an outlet 3 is located above the side wall. A valve seat 4 facing upward is provided inside, and a cylinder 5 is provided below the outlet 2 on the same axis. Further, between the valve seat 4 and the cylinder 5, the primary pressure chamber 6 adjacent to the inflow port 2 is provided.
The secondary pressure chamber 7 adjacent to the outlet 3 above the valve seat 4.
To form. An annular packing 8 that slides on the cylinder 5 and a piston 10 that mounts a water blocking packing 9 that closes the valve seat 4 are housed inside. A bottom lid 11 is connected to the bottom of the valve box 1, and a spring chamber 12 is formed between the piston 10 and the bottom lid 11. The spring chamber 12 accommodates a spring 13 that is locked to the bottom lid 11, and the spring 13
The decompression function is provided by the ascending force of the piston 10 by the and the descending force by the secondary pressure in the secondary pressure chamber 7. The bottom lid 11 is equipped with a one-way sealing packing 14 in order to release the pressure in the spring chamber 12 when the pressure in the spring chamber 12 becomes high to some extent, and to prevent underground water from entering the spring chamber 12. However, this can also be used as an air chamber by forming a large spring chamber 12 using, for example, a normal O-ring. In the valve box 1, an operating screw 15 is drilled upward, an operating rod 16 screwed onto the operating screw 15 is positioned, and an upper lid 17 is connected. The water blocking packing 9 is fixed by the valve piece 18 and the nut 19 so as not to come off from the piston 10.

 Next, the operation mode of the present invention will be described.

FIG. 1 shows a state in which water is passed through by opening the faucet at the end of the pipe. In this state, water from the inflow port 2 passes through the primary pressure chamber 6 and the valve seat 4 and the secondary pressure chamber. Flowing into 7,
It flows through the outlet 3 to the downstream pipe. When the faucet is opened further, the secondary pressure in the secondary pressure chamber 7 decreases,
The restoring force of the spring 13 raises the piston 10 to increase the flow rate. On the contrary, when the faucet is closed, the secondary pressure rises and the spring
The piston 10 is lowered by compressing 13 and the flow rate is reduced. When the faucet is completely closed, the secondary pressure becomes maximum, and the water blocking packing 9 contacts the valve seat 4 and shuts off the primary water from the inflow port 2. The strength of the spring 13 may be determined in advance so that the secondary pressure at this time becomes the set pressure. It is of course possible to change the strength of the spring 13 by providing an adjusting screw so that the set pressure can be adjusted freely. Further, as the water blocking packing 9, instead of using a flat packing as shown in the figure, the shape of the valve seat 4 may be changed and an O ring may be used. By any chance, the spring chamber 12
If water enters and accumulates in the piston, it may interfere with the normal operation of the pressure reducing valve.However, in the present invention, the one-way sealing packing 14 works
When 10 descends, the water in the pressure chamber 12 can be pushed out, so that it does not interfere with its normal operation. Further, also in the normal state and when the piston 10 rises, the unidirectional sealing packing 14 also prevents the underground dirty water from entering the spring chamber 12.

For example, if you want to stop the water to replace packing such as a faucet, you can attach a handle separately and rotate the operating rod 16. The operating screw 16 lowers the operating rod 16 and the water blocking packing 9 is used as the valve seat. Water can be stopped by pressing on 4. In addition, if the cylinder 5 and the portion where the water blocking packing 9 contacts the valve seat 4 have the same diameter, even if the primary pressure fluctuates, the secondary pressure does not fluctuate, and a precise pressure reducing valve is provided accordingly. However, when the set secondary pressure is allowed to fluctuate to some extent, the diameters of the inner peripheral walls of the cylinder 5 and the valve seat 4 may be made the same so that the piston 10 can be easily pulled out from above. At this time, the operating rod 16 and the piston 10 can be easily connected to each other so that the piston 10 can be pulled out more easily.

In the conventional underground piping, the instep water stopper was used on the upstream side of the pressure reducing valve, but it can be omitted in the present invention.

 Next, FIG. 2 will be described.

FIG. 2 shows an embodiment when it is used for indoor piping in a cold region, and the differences from the one in FIG. 1 are as follows. In the figure, the same parts as those in FIG. 1 are designated by the same reference numerals.

In the present embodiment, the valve box 1 is formed by inclining the axis of the valve portion by 30 ° toward the outlet side with respect to the mounting axes of the inlet 2 and the outlet 3, and the piston 10 is provided with a frictional force. In order to make the size smaller, a one-way sealing annular packing 8 is mounted, and a valve piece 18 integrally formed with a specially shaped water blocking packing 9 is mounted.
Between the piston (10) and the valve piece (18), a one-way sealing escape packing (20) for letting the secondary pressure escape to the primary side only when the secondary pressure becomes larger than the primary pressure. The valve box 1 is not directly provided with an operating screw, the upper lid 17 is provided with an operating screw 15, and the operating rod 16 is screwed. The operating rod 16 has an intake hole 21 formed therein, and normally closes the intake hole 21. The intake valve body 23 equipped with an O-ring 22 is pressed against the intake valve seat 25 by the intake spring 24 to the intake hole 21. To prevent water leakage. The operation rod 16 is equipped with a water leakage stop ring 27 having two water leakage prevention packings 26, and should water leak into the intake hole 21,
Raise the water stop ring 27 until it abuts the handle 28, and
Water is stopped by the individual leak-proof packing 26.

The mode of operation as a pressure reducing valve is almost the same as that of FIG. 1, but since the one of this embodiment is used for indoor piping, there is no concern that dirty water will enter the valve box 1, and therefore the spring chamber 12
Is open to the atmosphere.

In cold regions, it is necessary to operate the upstream antifreeze water tap to drain water from the piping during the winter, but when draining water with the faucet open, the inside of the valve box 1 will be atmospheric. Since it is released to, the spring 13 is pressed and the piston 10 rises to the maximum,
The water in the pipe can be drained smoothly. At this time, the outlet 3 is located above the inlet 2, and the valve seat 4
Since the valve is inclined, there is no accident such as residual valve water sealing the valve seat 4 and freezing, and water does not come out when water is re-passed. Furthermore, the amount of water remaining in the pipe is reduced to that extent. be able to. In the case of so-called portal type piping with upper and lower bent parts, it is necessary to install an intake valve separately in the piping to completely drain water,
In the present embodiment, since the intake device is provided in the operating rod 16, there is an advantage that it is possible to save the labor of installing the intake valve in the piping. At the time of draining water, when the pressure inside the pipe is lower than the atmospheric pressure, the intake spring 24 is compressed and the intake valve body 23 descends. And it is done completely. In addition, when a negative pressure is generated in the water supply pipe due to water cutoff work or the like, it naturally functions as a so-called vacuum breaker that supplies the atmosphere into the water supply pipe to reduce the negative pressure. When the water draining operation is performed with the faucet closed, the normal pressure reducing valve keeps the valve seat 4 closed due to the secondary pressure even if the inlet 2 side is opened to the atmosphere. Therefore, even if the intake valve is installed in the pipe, water cannot be drained from the secondary pipe. However, in this embodiment, when the primary pressure is lower than the secondary pressure due to the action of the relief packing 20, the secondary pressure is released to the primary side, so that the secondary pressure is reduced and therefore the spring 13 The piston 10 is completely lifted by being pressed by and the inside of the pipe is opened to the atmosphere through the intake hole 21, so that the water is completely drained. This has the advantage that the opening operation of the faucet at the time of draining, which is often forgotten, can be omitted, freezing accidents can be reduced by that much, and it has come to be used recently.
It is an indispensable constituent element when it is used for antifreeze faucet that senses temperature and drains water automatically.

The other operation modes are almost the same as those in FIG. Incidentally, in the past, an indoor water stopcock was often provided upstream of the pressure reducing valve to stop the water, but according to this embodiment, the indoor water stopcock can be omitted. Has the advantage.

As described above, in the present invention, the water stopper, which was conventionally required, can be omitted, and further, the piston is lowered to close the valve seat, so that the piston and the operating rod are not connected. It will be done, for example, the real public Sho 58-45346
Compared with, the structure is much simpler and the size can be reduced.

[Brief description of drawings]

FIG. 1 is a vertical sectional view in a water passing state showing an embodiment of the present invention, and FIG. 2 is a vertical sectional view showing another embodiment in the same water passing state. 1 ... Valve box, 2 ... Inlet, 3 ... Outlet, 4 ... Valve seat, 5 ... Cylinder, 6 ... Primary pressure chamber, 7 ... Secondary pressure chamber, 8 ... Annular Packing, 9 ...... Waterproof packing,
10 …… Piston, 11 …… Bottom lid, 12 …… Spring chamber, 13 …… Spring, 14 …… One-way sealing packing, 15 …… Operating screw,
16 …… Operation stick, 17 …… Top lid, 20 …… Escape packing, 21…
… Intake hole, 23 …… Intake valve, 27 …… Leak stop ring, 28 ……
handle

Claims (1)

[Scope of utility model registration request] 1. An inlet is provided below the side wall and an outlet is provided above the side wall.
An upward facing valve seat is provided in the middle part, a primary pressure chamber adjacent to the inlet is formed below the valve seat, and a secondary pressure chamber adjacent to the outlet is formed above the valve seat, and the primary pressure chamber is formed. A valve box having a cylinder coaxial with the valve seat below, a ring packing that slides on the cylinder, and a piston equipped with a water blocking packing that closes the valve seat, and a spring chamber formed at the lower end of the piston. The spring that is housed and gives upward pressure to the piston and basically separates from the piston,
A pressure reducing valve with a water stop device, which is located above it and has an operating rod that stops the water by applying downward pressure to the piston.