JPH0330885Y2 - - Google Patents

Description

[Detailed Description of the Invention] The present invention relates to a pressure reducing valve for use in cold regions that can quickly discharge water on the secondary side in one operation.

Conventionally, pressure reducing valves used in cold regions have a water drain such as a pico stock attached to the bottom of the valve body, and when draining water at night, first close the stop valve provided on the upstream side of the pressure reducing valve, and then open the water drain. The water in the pressure reducing valve itself and the secondary piping was drained from there. However, this type of system requires two operations, and since the area of the drain port of the drain is small, it takes a long time to drain the water, and it is prone to freezing.

The purpose of the present invention is to eliminate the above-mentioned defects and provide a pressure reducing valve for use in cold regions that can quickly discharge water from the secondary side in a single operation. Another purpose of this is to minimize the frictional force between the piston and cylinder to ensure stable operation.

The basic structure of the present invention for achieving the above object is as follows.

In other words, an inlet and an outlet are provided on the sides, cylinders are provided inside that are adjacent to the upper and lower sides of the inlet, a downward facing valve seat is formed at the bottom end of the lower cylinder, and the cylinder and shaft center are provided at the bottom end. Inside the valve box, which has different drainage ports, are two ring-shaped packings that closely fit the cylinder, a piece packing that closes the valve seat, and a piston with a diaphragm mounted above the upper ring-shaped packing. The piston is moved up and down by the upward secondary water pressure acting on the diaphragm and the downward force of the spring to provide a pressure reducing function, and the piston is connected to an operating rod disposed above the piston, and the piston is connected to an operating rod disposed above the piston. At the bottom, there is a drain valve that is normally pressed by a spring to shut off the drain channel, and when draining water, the operating rod and the piston connected to the operating rod are lowered by operating the handle.
The two ring-shaped gaskets shut off water from the inlet, and the piston presses the drain valve to open the drain channel.

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

In the figure, reference numeral 1 denotes a valve box of the pressure reducing valve of the present invention, and an inlet 2 serving as a primary side port and an outlet 3 serving as a secondary side port are opened on the side. Inside, cylinders 4 and 5 are provided above and below the inlet 2, and a downward facing valve seat 6 is provided at the lower end of the cylinder 5. A drain port 7 is opened at the lower end with different axes from the cylinders 4 and 5, and a passage from the outlet 3 to the drain port 7 is defined as a drain channel 8. A piston 9 that is housed in the valve box 1 and performs a pressure reducing action slides on the cylinders 4 and 5.
Ring-shaped packings 10 and 11 are attached, and a valve piece 13 with a piece packing 12 attached to the lower end is connected by screws. A large-diameter upper chamber 16 is formed below a bonnet 15 connected to the upper end of the valve box 1 with screws 14, and the upper chamber 16 is used as a pressure receiving chamber 17 that receives secondary water pressure and the upper side thereof is opened to the atmosphere. A diaphragm 19 divided into two chambers 18 is fixed to the upper end of the piston 9 via a sandwich plate 20 with a joint 21.
The outer periphery of the valve body 1 is fixed by the upper end of the valve body 1 and the bonnet 15. A cam case 23 is connected and fixed to the upper end of the bonnet 15 with a nut 22. Cam case 2
As shown in FIG. 2, the cam handle 26 is made up of two circular cam parts 24 and a handle part 25 that sandwich the cam part 24 between the two circular cam parts 24 and the handle part 25. As shown in FIG. 28, so when it rotates, it rotates in the vertical direction while moving its axis, and the operating rod 27 also moves up and down accordingly. The operating rod 27 has a vertically long notched hole 29 in its lower part, and is connected to the piston 9 by a pin 30 passed through the vertically long notched hole 29.
The piston 9 is housed in a vertical hole 31 formed at the upper end thereof, and is always subjected to a downward force from a spring 32 secured to the lower end of the operating rod 27. A drain valve box 35 having a downward facing valve seat 33 and a side hole 34 is connected to the lower end drain channel 8 of the valve box 1, and the valve seat 33 is connected inside the drain valve box 35.
Drain valve 37 equipped with a gasket 36 to block the drain valve 37
is housed by being pressed against the valve seat 33 by a spring 38, and the tip of the guide portion 39 is made to protrude from the upper end of the drain valve box 35. The drain valve 37 is pressed by the spring 38 with a force stronger than the downward pressing force caused by the set secondary pressure of the pressure reducing valve.
An adjusting nut 40 is connected to the lower end of the drain valve box 35 so as to press it against the valve seat. Reference numeral 41 is a conduit passage for guiding the secondary pressure water on the side of the outlet 3 to the pressure receiving chamber 17.

Next, the operating mode of the present invention will be explained.

FIG. 1 is a cross-sectional view when water is supplied from a collar or the like (not shown) provided at the end of the secondary piping, and water from the inlet 2 passes through the gap between the valve seat 6 and the piece packing 12. Then it flows to the outlet 3. At this time, the diaphragm 19 and the drain valve 37 prevent water from leaking elsewhere. If the collar is further opened from this state, the pressure on the secondary side will decrease, so the upward force acting on the diaphragm 19 through the conduit passage 41 will also decrease, and the restoring force of the spring 32 will cause the piston 9 to descend, increasing the flow rate. However, if the bell is turned in the direction of closing, the pressure on the secondary side increases, compressing the spring 32, and the piston 9 rises, reducing the flow rate. Since the piston 9 reaches its maximum, the piston 9 stops in the highest position, that is, the piece packing 12 comes into close contact with the valve seat 6, blocking the pressure water from the inflow port 2. The strength of the spring 32 may be selected in advance so that the secondary side pressure at this time is the set pressure. In this state, the ring-shaped gasket 10 is in close contact with the cylinder 4, and the bridge gasket 12 is in close contact with the valve seat 6, blocking water from the inlet 2 side. If the diameter of the part that contacts the valve seat 6 is the same as that of the cylinder 4, the inlet port 2
Since the pressure water from the piston 9 acts equally on the up and down sides of the piston 9, even if pressure fluctuations occur on the primary side, the piston 9 will not move up or down.
Therefore, the secondary pressure does not fluctuate. In other words, it functions as a complete pressure reducing valve. At this time, the drain valve 37 is pressed by the spring 38 and closes the valve seat 33, but if the water pressure on the outlet 3 side rises to some extent above the set secondary pressure due to water hammer or a rise in water temperature, for example, the spring 38 is pressed. If the drain valve 37 is compressed and the drain valve 37 is lowered to release the abnormal pressure to the drain port 7 side, it will function as a so-called commercially available safety valve. The relief pressure is adjusted using an adjustment nut 40.

Next, when draining water from the secondary side piping during the winter, all you have to do is turn the cam handle 26 vertically to the left as shown in the figure while the water is flowing. It descends without rotating, and the upper end of the vertical notch hole 29 is in contact with the pin 30, or before that, the piston 9 is also pushed down by the spring 32 and the ring-shaped packing 11 is in close contact with the cylinder 5. , and the ring-shaped gasket 10 block water from the inlet 2. When the valve piece 13 is further lowered, the lower end of the valve piece 13 pushes open the drain valve 37 to open the drain channel 8, so that the water in the outflow side piping starts to be discharged from the drain port 7 through the outlet 3 and the side hole 34. The cam handle 26 rotates 180 degrees, the piston 9 stops descending, and the water is completely drained. However, since the cross-sectional area of the drain channel 8 and the drain port 7 is made sufficiently large, the water in the outflow pipe is completely drained. and pressure receiving chamber 1
All the water inside 7 is quickly drained from the drain port 7,
Therefore, accidents due to freezing will not occur. During water flow, the pin 30 comes into contact with the lower end of the vertically elongated notch hole 29 to prevent the piston 9 from descending any further. Naturally, in this state, the ring-shaped packing 11 may come into close contact with the cylinder 5. Drain valve 39
There's no need to push it open.

When it is desired to remove the valve piece 13 due to a failure of the piece seal 12 or the like, the valve piece 13 can be easily removed using a screwdriver by removing the drain valve box 35. At this time, the pin 30 is locked in the vertical notch hole 29 and the piston 9 does not rotate.
It can also be easily removed. In addition, if the valve piece 13 is removed after the draining state is established, the water in the outflow side piping will not leak out from there, and there is no need to close the valve provided on the upstream side each time, which is convenient. A drainage pipe is usually connected to the drain port 7, but if the drain port 7 is located coaxially with the piston 9, it becomes difficult to remove the valve piece 13. However, in the present invention, the drain port 7 is offset from the axis of the piston 9 to such an extent that the valve piece 13 can be removed, so the above problem does not occur.

In the above embodiment, the piston was moved up and down by a cam, but it may also be moved up and down by a normal screw, and one embodiment of this is shown in the third example.
The main part is shown in the figure as a longitudinal sectional view. Note that in FIG. 1, similar parts are given the same reference numerals.

In FIG. 3, the operating rod 27, which is screwed into the bonnet 15 with a screw 42 and moves up and down with the rotation of the handle 43, is bored inside to accommodate the spring 32.
The strength can be adjusted using an adjustment screw 44. In other words, when adjusting the set secondary pressure, remove the handle piston 45 and tighten the adjustment screw 45.
If you push down, the set secondary pressure will increase, and if you push it in the opposite direction, it will decrease. The operating rod 27 and the piston 9 are connected by a screw 30' that protrudes into a vertically elongated notch hole 29 formed in the operating rod 27. The diaphragm 19 is attached to a sandwich plate 20 instead of being attached directly to the piston 9.
The clamping plate 20 and the piston 9 are sealed with an O-ring 47. In other words, even if the piston 9 rotates due to handle operation, the diaphragm 1
9 to prevent excessive rotational force from acting on it. The piston 9 is seated on the sandwich plate 20, and the downward force of the spring 32 is applied to the piston 9, and the diaphragm 1
Since a lifting force due to water pressure is acting on the piston 9, the diaphragm 19, the sandwich plate 20, and the piston 9 move in the same manner under normal conditions. In addition, 48
is a stopper ring when the operation stick 27 is lowered.

As described above, the present invention has the effect of quickly discharging the water on the secondary side with a single operation without stopping the stop valve on the upstream side. Frictional force is generated between the ring-shaped packing 10 and the cylinder 4.
Since there is only the frictional force between the pistons 9 and
It is more reliable, and in particular, there is less risk that the seal will swell over time, causing the set pressure to fluctuate or the flow rate to decrease.
Since the axial center is different from that of the piston 9, the valve piece can be easily repaired.
Furthermore, when the water pressure on the outlet side rises to some extent above the set secondary pressure due to water hammer or rising water temperature, the drain valve functions to release the abnormal pressure to the drain outlet, which has the advantage of functioning as a so-called commercially available safety valve. have

[Brief explanation of the drawing]

Fig. 1 is a vertical cross-sectional view of an embodiment of the present invention in a water-flowing state, Fig. 2 is a vertical cross-sectional view of the main part in the right angle direction, and Fig. 3 is a main part showing another embodiment. FIG. 1...Valve box, 2...Inflow port, 3...Outflow port,
4, 5... Cylinder, 6... Valve seat, 7... Drain port, 8... Drain channel, 9... Piston, 10, 11
...Ring-shaped patchkin, 12... Piece patchkin, 1
3...Valve piece, 15...Bonnet, 16...Upper chamber, 17...Pressure receiving chamber, 18...Operation room, 19...
Diaphragm, 23...Cam case, 26...Cam handle, 27...Operation stick, 32...Spring, 3
5...Drain valve box, 37...Drain valve, 38...Spring.

Claims (1)

[Scope of utility model registration request] An inflow port and an outflow port are provided on the side, and a cylinder adjacent to the top and bottom of the inflow port is provided inside, a downward facing valve seat is formed at the bottom end of the lower cylinder, and the axis center is different from that of the cylinder at the bottom end. A valve box with a drain port provided therein, a ring-shaped packing that is always in close contact with the upper cylinder, a ring-shaped packing that is in close contact with the lower cylinder only when draining water, and a piece packing that closes the valve seat below it. Furthermore, a diaphragm is installed that divides the upper chamber formed by the bonnet connected to the upper end of the upper cylinder and the valve box into an upper operation chamber and a lower pressure receiving chamber, and a spring constantly applies downward pressing force. a piston that receives water, an operating rod that connects the piston so as to be able to move up and down, and a drain that is located below the piston and receives an upward pressing force that is stronger than the downward pressing force caused by the set secondary pressure due to a spring. A pressure reducing valve for cold regions, characterized in that when draining water, a piston is lowered and the drain valve is pressed to open the space between the outflow port and the drain port.