JPH0111809Y2 - - Google Patents

Description

[Detailed Description of the Invention] The present invention relates to a check valve that is used in cold regions by being connected to indoor piping on the downstream side of an antifreeze faucet.

Conventionally, backflow prevention valves have been installed in the downstream piping of boilers and other water heaters to prevent thermal deformation of plastic parts such as meters due to backflow of hot water when negative pressure is generated in the water mains due to a water outage, etc. It is often done to make a profit. In addition, even when the water heater is not in use, in order to prevent sewage from being sucked in from the faucet at the end of the pipe and contaminating the main pipe, a backflow prevention valve should be installed downstream of the antifreeze faucet. It can also be found inside indoor plumbing. However, in any case, even if you try to drain the water by operating the anti-freeze water faucet during the freezing season, the backflow prevention valve will operate and the water in the pipes will not be able to be drained. Faucets were installed at the front and rear, and after operating the antifreeze faucet, both faucets were opened to drain the water.

As a result, the cost is high and the operation is complicated, and water may gush out if you forget to close the faucet when water is flowing, or the backflow prevention valve may remain closed, causing the valve to freeze and prevent water from flowing when water is flowing. There was also a drawback.

In view of the above, this invention allows for reliable water removal with simple operations, does not impede water reflow, and is automatically restored by water pressure when water is reflowed.
The purpose of this invention is to provide a check valve for use in cold regions, and the basic structure of the present invention for this purpose is as follows.

In other words, an inlet, an outlet, and a check face between them are provided on the same axis, a valve chamber is formed between the check face and the outlet, a water inlet chamber is formed between the inlet and the check face, and A check packing is installed in a valve box that has an operation chamber that opens perpendicularly or obliquely to the water chamber, and the valve body, which is always pressed toward the inlet by a spring, is connected perpendicularly or diagonally to the valve body. Contains an operating rod that opens between the inlet and outlet by pressing from a direction,
A large diameter pressing part is attached to the tip of the operation chamber side of the above operation stick.
The diameter of the adjacent downstream part is made slightly smaller to form a stopping part, and a recessed part in which the above-mentioned pressing part is locked is formed at the tip of the inflow side of the valve body. After draining the water from the valve, simply press the operating rod to move the valve body while compressing the spring, opening the space between the inlet and outlet, thereby preventing drainage from being obstructed or the flow path freezing. Moreover, since the operating rod is locked to the valve body, the operating rod and the valve element will not be returned to their original positions due to water pressure during draining, and when water is recirculated, the operating rod will automatically move due to the water supply pressure. It was designed so that it would return to normal.

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

In FIG. 1, reference numeral 1 denotes a valve box of the non-return valve of the present invention, which has an inlet 2 and an outlet 3 on the same axis. A mounting bracket 4 is connected to the outlet 3 side in consideration of ease of connection to piping and repair. A cylindrical non-return surface 5 is provided approximately midway between the inflow port 2 and the outflow port 3 on the same axis as the inflow port 2 and the outflow port 3, and a cylindrical non-return surface 5 is provided on the downstream side of the non-return surface 5. A large-diameter valve chamber 6 is formed, and the inner surface is used as a sliding surface 7. A water inlet chamber 8 is formed between the backstop 5 and the inlet 2, and an operation chamber 9 is formed by opening the upper part of the water inlet chamber 8 at an angle of 45 degrees.
A top lid 10 is connected to the top end. As shown in FIG. 2, the valve body 11 housed in the valve box 1 consists of a check part 13 to which a check gasket 12 is mounted at the tip, four support arms 14, and a spring holding part 15. The outer periphery of the support arm 14 and the spring holding part 15 is the same as that of the valve box 1.
It is made to slide using the sliding surface 7 of as a guide. Further, the inside is bored to form a passageway 16, and an entrance/exit 17 is opened to the passageway 16 between the support arms 14, and a circular recess 18 is bored at the tip of the check portion 12. The valve body 11 is a spring 19
The support arm 14 is always pressed in the direction of the inlet 2, and in the state shown in the figure, the tip of the support arm 14 comes into contact with the left end of the non-return surface 5 to prevent further movement. Reference numeral 20 denotes an operation rod, which has a large-diameter pressing portion 2 at its tip on the operation chamber 9 side.
1. The downstream adjacent part is made slightly smaller in diameter to form the stop part 22. An operating section 23 is provided at the upper end,
Gaskets 25 and 26 are attached to the middle part to tightly contact the sealing surface 24 inside the upper lid 10. The sealing surface 24 has a smaller diameter than the non-returning surface 5. Check gasket 12 of valve body 11 and gaskets 25 and 26 of operating rod 20
The valve uses a one-way sealing gasket with a Y-shaped cross section, which reduces frictional resistance compared to using a circular O-ring, making the valve operation easier and more reliable. In addition, in the figure, two gaskets are attached to the operation stick 20 for safety reasons, but the gasket 25 may be omitted, the gasket 25 may be replaced with a flat gasket, or the operation may be further enhanced by using a diaphragm or the like. It can also be made lighter. Reference numeral 27 is a clip link for holding the spring, and also serves as a stopper when the valve body 11 moves to its maximum.

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

Figure 1 shows a state in which the antifreeze faucet is open and the faucet at the end of the pipe (not shown) is closed, that is, the water is stopped. The water compresses the spring 19 and pushes open the valve body 11, and the water that has passed through the water inlet chamber 8 and the valve chamber 6 enters the water passage 16 through the inlet/outlet 17 of the valve body 11, and flows downstream from the outlet 3. It flows out into the pipes.
At this time, since the gaskets 25 and 26 are in close contact with the sealing surface 24, there is no leakage from there. When the faucet is closed from this state, or when negative pressure is generated in the water main, the flow of water from the inlet 2 to the outlet 3 side disappears, so the valve body 11 is pressed by the spring 19. It immediately moves to the right and stops moving with the non-return gasket 12 in close contact with the non-return surface 5 as shown in the figure. That is, even if negative pressure is generated on the main pipe side, hot water or sewage will not flow back from the outlet 3 side, and the above-mentioned accident can be completely prevented. Also, at this time, it is possible that the operating rod 20 is lowered by negative pressure and applies a pressing force to the valve body 11, but the valve body 11 is pressed by the spring 19, and the check surface 5 is larger than the sealing surface 24. Since the valve body 11 is configured to have the same diameter, there is no possibility that the valve body 11 will be pressed by the operating rod 20 to open the space between the inlet 2 and the outlet 3.

Next, when operating the anti-freeze faucet to set it to the drain state, it is best to press down the operating rod 20 from the state shown in the figure, so that the pressing part 21 comes into contact with the tip of the check part 13 of the valve body 11, and the state When pressed further down, the valve body 11 moves to the left using the sliding surface 7 as a guide.
The operating portion 23 of the operating rod 20 comes into contact with the upper lid 10 and the pressing portion 21 enters the recess 18 of the valve body 11 and stops moving. That is, the state shown in FIG. 3 is reached. At this time, the check portion 13 of the valve body 11 has completely separated from the check surface 5, so the water flow path will not be blocked due to freezing, so water will not come out when water is recirculated. Such a thing does not happen.
At the time of drainage, the water pressure of the difference between the heads of the downstream piping acts on the operating rod 20 as a rising force, but the non-returning part 13
The tip contacts the stop portion 22, and the pressing force of the valve body 11 due to the spring 19 and water pressure during draining acts as a frictional force on the operating rod 20, so that the operating rod 20 naturally rises under normal conditions. There isn't. However, when there is a large difference in the head of the downstream piping, such as when piping is installed on the second floor, or when the backflow prevention valve of this invention is installed vertically,
The operating rod 20 returns naturally due to vibrations, etc., and returns to the state shown in Fig. 1, and the outflow port 3 and inflow port 2
There is a risk that the flow path between the drains will be blocked and drainage will not take place.

However, in the present invention, as shown in FIG. 3, when the operation stick 20 is pressed, the pressing part 21, which has a slightly larger diameter than the stop part 22, is locked to the upper end of the concave part 18 of the valve body 11, and the spring 19 always keeps the valve open. Since the body 11 is pressed in the direction of the inlet 2, the operating rod 20 will not return naturally due to vibrations or the water flow level during drainage. Also at this time Patsukin 25
has separated from the sealing surface 24, but the seal 26
Since it is in close contact with the sealing surface 24, there is no water leakage from that part.

Next, when the antifreeze faucet is opened and water is supplied again, the valve body 11 moves to the left due to the water pressure.
Therefore, the locked state between the valve body 11 and the operating rod 20 is released, and the operating rod 20 is raised by the water pressure and returns to its previous position. In addition, if you want to return the operation stick 20 manually, if you rotate the operation stick 20 and pull it up, some pressing force will be generated in the downstream direction on the valve body 11 during rotation, and the pressing part 21 will be Once removed from the recess 18, the operating rod 20 can be returned to its original position more smoothly.

FIG. 4 is a longitudinal cross-sectional view of a main part showing another embodiment of the present invention, and the differences from the above embodiment are as follows. Note that the same reference numerals are given to the same parts as in FIG. 1 below.

In FIG. 4, the valve body 11 has a rod-shaped guide part 28 on the outflow port 3 side and a cylindrical guide part 29 on the inflow port 2 side, and each guide plate 30 has several passages 16. The inner peripheral wall of the check face 5 formed in the shape of a valve seat is moved. Therefore, water from the inlet 2 passes through the water inlet chamber 8, the recess 18 of the valve body, and the inlet/outlet 17, and flows from the valve chamber 6 through the water passage 16 toward the outlet 3 side. The operation room 9 is provided in a direction perpendicular to the water entry chamber 8,
Protruding therein is a large-diameter pressing part 21 whose tip is formed into a conical shape as shown in the figure, and an operating rod 20 whose downstream side is slightly smaller in diameter and has a stop part 22. When the operation stick 20 is pressed, the pressing part 2
The valve body 11 retreats while being pressed by the tapered surface of the valve body 1 and compressing the spring 19, and the pressing portion 21 is locked to the upper end of the inner circumference of the recess 18, thereby preventing the operating rod 20 from returning. A plate-shaped check packing 12 is attached to the valve body 11.
Since the check face 5 in the shape of a valve seat is sealed, the distance the valve body moves can be reduced accordingly even when water is flowing or draining. At the time of maximum movement, the spring holding portion 15 is brought into contact with the right end of the guide plate 30. Note that the guide does not necessarily need to be provided at two locations, and the guide portion may be made longer so that it is provided at either one location.

Figure 5 shows an embodiment in which the water inside the valve box 1 and the outflow pipe can also be discharged from the check valve itself.The difference from the one in Figure 1 is that the operation chamber 9 faces downward. so that it is installed and the operation stick 20
A communication hole 31 that opens from between the gaskets 25 and 26 to the tip on the atmosphere side is provided, and the operation part 23
The tip is formed so that a vinyl tube for drainage can be attached, and other aspects are the same as the embodiment shown in the first figure. According to this embodiment, since the communication hole 31 is provided, water can be drained and air can be taken in from that part. Therefore, if it is installed near a faucet, etc., the water can be drained from the antifreeze faucet without opening the faucet. It also has the effect of functioning as an intake valve when installed in so-called gate-type piping, which has upper and lower bends in the piping.

The present invention has been explained above based on the embodiments shown in the drawings, but if a one-way sealing seal is used for the valve body 11 as shown in FIGS. It has the advantage that the water-stopping effect is more reliable than that using a plate-shaped non-return packing as shown in the figure. It is also possible to deform the check packing 12 to release abnormal pressure rises to the upstream side, such as when water is frozen due to forgetting to drain the water, thereby preventing damage to pipes and joints. When connecting the non-return valve of the present invention to piping, it may be connected horizontally as shown in the figure or vertically; however, when connecting horizontally, The one in Figure 4 has the operation chamber 8 facing upward, and the one in Figure 5 has the operation chamber 8 facing upward.
It is preferable to install it so that it faces downwards as this will minimize the amount of water remaining in that area, but it is not always necessary to do so. Also, although it is a matter of course, the mounting bracket 4 can be omitted and the valve box 1 can be
may be connected directly to the piping.

As described above, in this invention, water can be drained easily and reliably, and there is no need for the valve body to freeze and block the water passage, preventing water from coming out when water is supplied again. can automatically return when water is flowing,
Compared to the conventional system, which had two faucets before and after the backflow prevention valve, the cost is significantly lower.
There is no chance of water gushing out if you forget to close the faucet, and there is no problem with re-flowing the water.Furthermore, when draining water, the operating rod is locked to the valve body and does not vibrate until the water flows through the inlet. This has the effect that it will not return automatically due to the head difference with the downstream piping, and since the control rod is installed on the inlet side, it is easier to recycle than the one installed on the outlet side. A large amount of heat can be expected to be supplied when water is passed through,
The ice thawing time is shortened accordingly, and the operation stick 2
Using plate-shaped packing for 0 packing 25,
It also has the advantage that by incorporating a valve into the operating rod 20, it can easily function as a vacuum breaker.

[Brief explanation of the drawing]

FIG. 1 is a vertical cross-sectional view showing an embodiment of the present invention in a water-stopped state, FIG. 2 is a perspective view of the valve body in FIG. 1, and FIG. 3 is a diagram of the embodiment in FIG. FIG. 4 and FIG. 5 are vertical cross-sectional views of main parts showing other embodiments of the present invention. 1...Valve box, 2...Inflow port, 3...Outflow port, 5
...Return surface, 6...Valve chamber, 8...Water entry chamber, 9...
Operation chamber, 10...Top lid, 11...Valve body, 12...
Non-return gasket, 18... recess, 19... spring, 2
0...operation stick, 21...pressing part, 22...stopping part.

Claims (1)

[Scope of utility model registration request] An inlet, an outlet, and a check surface between them are provided on the same axis, a valve chamber is formed between the check surface and the outlet, a water inlet chamber is formed between the inlet and the check surface, and the water inlet chamber is formed between the inlet and the outlet. a valve box having an operation chamber that opens perpendicularly or obliquely to the valve body; a valve body that is housed in the valve body and is fitted with a check packing that closely contacts the check surface; The operating stick has a large diameter pressing part at its tip end facing the operating room, and a spring that applies a pressing force to the operating room. A backflow prevention device for use in cold regions, characterized in that the side portion has a slightly smaller diameter to form a stopper, and a concave portion in which the large-diameter pressing portion is locked is formed at the tip of the inflow side of the valve body. valve.