JPH0454488Y2 - - Google Patents

Description

[Detailed explanation of the idea] [Industrial application field]

The present invention relates to improvements in pressure reducing valves for boilers used in cold regions.

[Conventional technology]

Conventionally, this type of pressure reducing valve has generally been used, for example, Utility Model Publication No. 196479/1983, but all of these have a strainer, check valve, and negative pressure operation on the inlet side. It has a structure that includes a valve and a drain plug on the outlet side, which is the secondary side. Therefore, the structure is inevitably complicated and large, and the flow path shape is complicated, which increases flow path loss. Even if you open the plug and drain the water inside the valve box, the check valve remains closed, so it will inevitably freeze in that area.
Next, even if the antifreeze faucet was opened, water would not come out, which could easily lead to an accident.

[Problem that the idea aims to solve]

In view of the above points, the present invention simplifies the structure of the valve and increases the flow rate by attaching or housing the check valve and negative pressure operated valve to the piston. The valve is removed from the valve seat to open the primary and secondary flow paths to prevent accidents due to freezing.

[Means to solve the problem]

That is, the primary pressure chamber on the inlet side is formed below the secondary pressure chamber on the outlet side, and a pressure reducing spring is installed in the valve box having upper and lower sealing surfaces at the upper and lower ends of the partition wall between the two. It houses a piston that moves up and down due to downward force and upward water pressure applied to the diaphragm, houses a negative pressure operating valve in the lower end of the piston, and has a small diameter above it on the side of the secondary pressure chamber. At the same time, a check valve is fitted into the lower end of the valve box and is fitted into the upper sealing surface.
A push rod is arranged that allows the piston and check valve to be moved upward by means of a screw.

[Effect]

Due to the above structure, the piston normally moves up and down due to the above spring and the secondary pressure acting on the diaphragm to act as a pressure reducing valve, and when negative pressure is generated on the primary side, the check valve moves to the upper sealing surface. In addition to preventing the backflow of secondary water by being in close contact, the negative pressure operating valve works to suck in the atmosphere and reduce the negative pressure.When draining water, the pressure rod is moved upward with a screw to activate the check valve together with the piston. If necessary, the negative pressure operated valve can also be raised to allow complete drainage of water.

【Example】

The present invention will be described below with reference to embodiments shown in the drawings. In FIG. 1, 1 is a valve box of the pressure reducing valve of the present invention, and 2 and 3 are an inlet and an outlet provided protruding from the side wall of the valve box 1. 4 is a primary pressure chamber adjacent to the inlet 2, and 5 is a secondary pressure chamber adjacent to the outlet 3. Reference numeral 6 denotes a partition wall separating the primary pressure chamber 4 and the secondary pressure chamber 5, which has a through hole 7 in its center, an upper sealing surface 8 shaped like a valve seat at its upper end, and a lower sealing surface 9 at its lower end. 10 is a bottom cover connected to the lower end of the valve box 1, and a strainer 11 is attached to the upper end.
The upper end of the strainer 11 is brought into contact with the lower end of the partition wall 6, so that all the primary water from the inlet 2 flows through the strainer 11 to the outlet 3 side. A cylinder part 12 is formed inside the bottom cover 10, and a press rod 13 is screwed to the cylinder part 12 located below the cylinder part 12 so as to be vertically movable. A small hole is bored in the center to serve as an air intake hole 14. 15 is the bonnet;
A screw 1 is attached to the upper end of the valve body 1 through the diaphragm 16.
Connected and fixed by 7. 18 is a piston whose upper end is connected to a diaphragm 16 sandwiched between a spring receiver 19 and a sandwich plate 20 by a nut 21. A narrow diameter portion 22 is provided below the narrow diameter portion 2.
A small diameter flange portion 23 and a large diameter flange portion 24 are formed at the lower end of 2. A rectangular pressure reducing gasket 25 is attached to the large-diameter brim portion 24, and an annular gasket 26 that slides on the cylinder portion 12 of the bottom cover 10 is further attached below it. A valve chamber 27 is formed inside, and a communication hole 28 opening at the top and bottom of the annular packing 26 is bored to open into the valve chamber.
An air passage is formed from the primary pressure chamber 4 to the primary pressure chamber 4.
A valve seat 29 is provided at the lower end of the valve chamber 27.
A negative pressure operated valve 31 equipped with an O-ring 30 that is in close contact with the valve 9 is pressed downward by an intake spring 32. The narrow diameter portion 22 is equipped with a one-way sealing annular check packing 33 with a Y-shaped cross section that slides on the narrow diameter portion 22, and a square check packing 34 is attached to the lower end of the check valve. 35 is fitted and inserted so as to receive a downward pressing force from a check spring 36 locked to the spring receiver 19. Above bonnet 1
An adjusting screw 37 is screwed into the piston 5 so as to be movable up and down, and a pressure reducing spring 38 accommodated between the adjusting screw 37 and the sandwich plate 20 always applies a downward pressing force to the piston 18. Next, the operating mode of the present invention will be explained. Figure 1 shows a state in which the faucet at the end of the pipe is opened and water is flowing. In this state, high-pressure water from the inlet 2 passes through the strainer 11, the primary pressure chamber 4, and the through hole 7, and then passes through the low-pressure water. becomes secondary water, and the secondary pressure chamber 5
It flows into the downstream piping through the outlet 3. When the faucet is further opened, the secondary pressure in the secondary pressure chamber 5 decreases, and the upward force acting on the diaphragm 16 decreases, so the piston 18 descends due to the restoring force of the pressure reducing spring 38, increasing the flow rate. .
Conversely, as the faucet is closed, the secondary pressure increases and the upward force acting on the diaphragm 16 increases, compressing the pressure reducing spring 38 and causing the piston 18 to move upward, reducing the flow rate. When the faucet is completely closed, the secondary pressure reaches its maximum, and the pressure reducing gasket 25 comes into contact with the lower sealing surface 9, blocking the primary water from the inlet 2. The strength of the pressure reducing spring 38 may be adjusted in advance using the adjusting screw 37 so that the secondary pressure at this time becomes the set pressure. At this time, the check valve 35 is seated on the small diameter collar portion 23, and the check gasket 34 is not in contact with the upper sealing surface 8. When water is flowing, if negative pressure is generated on the main pipe side due to a water outage, etc., the secondary pressure will disappear, so the piston 18 will immediately descend under pressure from the pressure reducing spring 38, and at the same time, the piston 18 will be pressed against the check spring 36. Then, the check valve 35 also lowers, and the check gasket 34 comes into close contact with the upper sealing surface 8, and the check annular gasket 33 comes into close contact with the narrow diameter portion 22, so that water in the outflow side piping flows back toward the inlet 2 side. can be completely prevented. At this time, the negative pressure operated valve 31 presses the intake spring 32 and moves upward, and air from the air intake hole 14 flows into the main pipe through the communication hole 28, the primary pressure chamber 4, and the inlet 2. Reduce negative pressure. Next, when you want to drain water from the pipes during the winter, you can operate the anti-freeze faucet installed in the inflow side piping to drain water while the water is flowing as shown in the figure, and the secondary pressure in the outflow side piping is piston 1 because it runs out
8 is lowered to its lowest position, the check valve 35 is also lowered, and the check valve 34 comes into contact with the upper sealing surface 8 and stops. At this time, the negative pressure operation valve 31 rises and the pressure on the inlet 2 side becomes atmospheric, so that water can be drained from the inflow side piping, but the check valve 35 is activated and water cannot be drained from the outflow side piping. Therefore, in this invention, the pressure rod 1
By rotating and moving the press rod 13 upward, the negative pressure operating valve 31 first comes into contact with the upper end of the press rod 13 and is pushed open, and then the lower end of the piston 18 comes into contact. to move the piston 18 upward. When the piston 18 moves upward to a certain extent, the upper end of the small diameter flange 23 comes into contact with the lower end of the check valve 35, and the check valve 35 also moves upward. Finally, the pressing rod 13 comes into contact with the lower end of the bottom cover 10 and stops moving upward. In other words, the draining state shown in FIG. 2 is reached. In this state, the non-return gasket 34 and the decompression gasket 25 are
are separated from the upper sealing surface 8 and lower sealing surface 9, respectively, so the water in the outflow pipe can be completely drained, and furthermore, the water will not freeze even when the anti-freeze faucet is opened next time. The flow path is blocked and water does not come out.
Such an accident will not occur. In addition, if you forget to return the pressure rod 13 to the state shown in FIG. 1 at that time, the check valve 35 will not work and it will be impossible to prevent backflow. Since the negative pressure operation valve 31 is moved upward and the inflow port 2 and the air intake hole 14 are electrically connected, water will gush out from the air intake hole 14 and the user will immediately feel abnormal. Because of the age, accidents like the one mentioned above do not occur. However, if the above consideration is not required, the lower end of the negative pressure operated valve 31 is connected to the piston 18.
It is also possible to make it so that it does not protrude beyond the lower end of the . If the strainer 11 becomes clogged, it can be easily cleaned and repaired by removing the bottom cover 10. Next, explanation will be given based on the embodiment shown in the third figure. FIG. 3 is a vertical cross-sectional view showing another embodiment of the present invention, also in a water-flowing state, and the differences from that in FIG. 1 are as follows. Note that parts similar to those in FIG. 1 are given the same reference numerals. The valve box 1 does not have the strainer 11 and bottom cover 10 shown in FIG. 1, but has a screw at the lower end.
By the rotation of the cap nut 39 screwed into the screw, the pressing rod 13, which is locked to the cap nut 39, moves up and down without rotating. Therefore, when the vinyl hose 40 is attached in consideration of water leakage, etc., the vinyl hose 40 does not rotate, making the operation easier. The lower sealing surface 9 is a cylinder surface, the piston 18 is equipped with an annular pressure reducing packing 25 that slides on the lower sealing surface 9, and the narrow diameter portion 22 is fitted with a non-return annular packing 33. A ball-shaped negative pressure operating valve 31 is housed inside, and an O-ring is used for the valve seat 29. A small-diameter projection 41 is provided at the tip of the pressing rod 13, and the negative pressure operated valve 31 is pressed by the small-diameter projection 41, but the small-diameter projection 41 may be omitted if this is not necessary. A gland 42 is connected to the bonnet 15, and an adjustment screw 37 is screwed onto the outside of the gland 42, and a spindle 43 is screwed onto the inside so that the gland 42 can move vertically. The spindle 43 is capable of locking a pipe hanger 45 connected to its tip. In this state, the pipe hanger 45 does not contact the roll pin 44, and when the spindle 43 is moved up and down by the handle 46, or when the pressure on the primary side disappears, such as when draining water, the pipe hanger 45 is locked to the roll pin 44. I'm trying to make it happen. Therefore, in this embodiment, by rotating the handle 46, the piston 18 is also raised by being locked to the spindle 43, and the pressure reducing gasket 25 is moved downward, without having to install an indoor water stop valve in the middle of each piping. This is convenient because water can be stopped by coming into close contact with the sealing surface 9. In addition, since the lower sealing surface 9 and the cylinder 12 have the same diameter, if you wish to pull out the piston 18 for repairing the gasket, etc., simply remove the bonnet 15 and the piston 18 will come out of the valve box 1 as it is, making the repair easier. becomes very easy. Other operating modes are almost the same as those in FIG. In the embodiments shown in FIGS. 1 to 3, the air intake port 14 may not be provided in the pressure rod 13 itself, but may be provided in the bottom cover 10 or the valve box 1 itself.

[Effect of the idea]

As described above, in this invention, the check valve is installed on the secondary side of the piston, and the negative pressure operated valve is housed inside the primary side of the piston, so the structure is simple and compact, and the flow path shape is also simple. This reduces pipe resistance, and since the check valve can be opened together with the piston by upward movement of the pressure rod attached to the lower end of the piston, there is no blockage of the flow channel due to freezing when water is drained. be.

[Brief explanation of the drawing]

Fig. 1 is a longitudinal cross-sectional view showing one embodiment of the present invention in a water-flowing state, Fig. 2 is a longitudinal cross-sectional view in a drained state, and Fig. 3 is a longitudinal cross-sectional view showing another embodiment of the present invention. , is a vertical cross-sectional view in a state where water is flowing. 1... Valve box, 2... Inlet, 3... Outlet, 4
...Primary pressure chamber, 5...Secondary pressure chamber, 6...Partition wall, 7...Through hole, 8...Upper sealing surface, 9...Lower sealing surface, 10...Bottom cover, 11...Strainer ,1
3...Press rod, 14...Air intake hole, 15...Bonnet, 16...Diaphragm, 18...Piston, 22...Small diameter part, 25...Decompression packing,
27... Valve chamber, 28... Communication hole, 31... Negative pressure operating valve, 32... Intake spring, 34... Check packing, 35... Check valve, 36... Check spring, 37...
...adjustment screw, 38 ... pressure reduction spring, 39 ... cap nut, 42 ... gland, 43 ... spindle, 4
6...Handle.

Claims (1)

[Scope of utility model registration request] A primary pressure chamber is formed on the inlet side, a secondary pressure chamber is formed on the outlet side, and the primary pressure chamber is located below the secondary pressure chamber, and there is a through hole in the center separating both pressure chambers. a valve box having a partition wall having upper and lower sealing surfaces at its upper and lower ends; a bonnet connected to the upper end of the valve box via a diaphragm therebetween; A piston that stops water, is connected to the diaphragm through the through hole, and is biased downward by a pressure reducing spring located above the diaphragm; a negative pressure operated valve that cuts off communication of the inflow side pressure water with the atmosphere; and a negative pressure operated valve that is fitted into a narrow diameter portion provided on the secondary pressure chamber side of the piston and tightly contacts the upper sealing surface to prevent backflow. A pressure reduction device for cold regions comprising a check valve that is biased downward by a check spring, and a pressure rod that is arranged at the lower end of the valve box and can move upward the piston and the check valve that is locked to the piston. valve.