JPS5842536Y2 - Valve structure of backflow prevention type antifreeze faucet - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a valve structure for a backflow prevention type antifreeze faucet that prevents water from flowing backward from an outlet to an inlet.

Conventionally, when hot water equipment such as instantaneous water heaters was directly connected to the piping downstream of the antifreeze faucet, negative pressure would occur due to water outages, etc. on the upstream side of the antifreeze faucet, that is, on the main pipe side. In such cases, hot water inside the hot water supply equipment often flows backwards, causing thermal deformation or damage to plastic parts of plumbing fixtures.

However, if a backflow prevention valve is installed in the downstream piping of the antifreeze faucet to prevent backflow, the backflow prevention valve will work and the water in the piping will not drain even if the antifreeze faucet is operated. The problem arises that it cannot be done.

Therefore, it is possible to install a backflow prevention valve upstream of the antifreeze faucet, but since it is buried in the ground, it would be a laborious task to repair it even if an accident occurs with the backflow prevention valve. Become.

In order to eliminate the above-mentioned drawbacks, the present invention attaches a one-way sealing packing that functions as a check valve to the piston, and by pulling out the piston, the above-mentioned packing can be repaired.
The present invention relates to a valve structure for an antifreeze faucet that can be easily inspected on the ground.

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

In FIG. 1, reference numeral 1 denotes the valve body of the antifreeze faucet of the present invention, which has an inlet 2, an outlet 3, and a drain 4 in order from the bottom on the side wall.

Inside, four cylinders 5, 6, 7.8 are arranged in order from the top.

The piston 9 has a small-diameter portion 10 formed in the middle thereof, and is joined by a screw at that portion.

On the outer periphery, there is a ring-shaped packing 11 on the upper piston 9'.
12, and the lower piston 9'' has a ring-shaped gasket 13.
14, and inside, a communication hole 15 in the central axis direction is provided in the upper piston 9', a communication horizontal hole 16 is provided intersecting with the communication hole 15, and a communication hole 15' is provided in the lower piston 9''. ing.

Between the upper piston 9' and the lower piston 9'', a one-way sealing packing 17 with a roughly L-shaped cross section, which widens from the root to the tip, is installed with a screw to an appropriate tightness to ensure flow. It's making and pinching.

In this embodiment, the one-side private and opposite gasket 17 has a size such that its tip lightly contacts the cylinder 7, but this is not necessarily an essential requirement, and when backflow occurs, a small amount of water A gap may be provided to allow the flow to immediately close the cylinder 7.

A conduit passage 18 is formed between the cylinder 7 and the narrow diameter portion 10 of the piston 9, and the one-way sealing gasket 17 is located in the conduit passage 18, at least in the open state. There is.

Although not shown, the valve body 1 is connected to an upper support metal fitting through a pipe 19, and the piston 9 is connected to an upper operating mechanism such as a spindle through a rod 20.

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

Figure 1 shows a state in which the anti-freeze faucet is open and no water is being supplied by the faucet or water heater (σ), that is, the water is stopped. Then, the water from the inlet 2 first flows into the conduit 18, pushes the tip of the one-way sealing packing 17, passes through the gap with the cylinder 7, and flows to the outlet 3.

Although not shown, water from the outlet 3 flows through downstream piping to a faucet or water heater.

At this time, since the ring-shaped packing 12 is in close contact with the cylinder 6 and the ring-shaped packing 14 is in close contact with the cylinder 8, no water leaks into the living room.

When negative pressure is generated on the main pipe side in this state, the flow of water from the inflow port 2 to the outflow port 3 stops, so the one-way sealing packing 17 expands outward, and its tip contacts the cylinder 7, causing the water to flow. The flow of water from the outlet 3 to the inlet 2 is blocked.

The greater the pressure difference between the inlet 2 side and the outlet 3 side, the better the adhesion of the one-way sealing packing 17 to the cylinder 7, and therefore, accidents such as hot water in the instantaneous water heater flowing back to the main pipe side are prevented. It won't happen.

Next, when you want to drain the water in the downstream piping, it is best to raise the rod 20 using the operating mechanism at the top.
The piston 9 connected to the cylinder 7 also rises at the same time, and the ring-shaped gasket 13 first comes into close contact with the cylinder 7 to block water from the inflow port 2, and then the ring-shaped gasket 12 connects to the cylinder 6.
The water in the downstream pipe passes through the outlet 3 and the gap between the cylinder 6 and the outer periphery of the piston 9, and is discharged into the ground from the drain 4.

At this time, since the ring-shaped packing 11 is in close contact with the cylinder 5, water in the downstream piping does not enter the pipe 19.

Of course, in this state, due to the sealing properties of the ring-shaped packing 13, backflow to the main pipe side does not occur.

When opening the bottle again, it is best to lower the rod 20 so that the non-glue gasket 12 comes into close contact with the cylinder 6.
Thereafter, the ring-shaped gasket 13 separates from the cylinder 7 and returns to the open state shown in the figure.

Due to the communication holes 15, 15' and the communication horizontal hole 16 that open up and down inside the piston 9, when the piston 9 moves up and down, it does not create negative pressure or try to compress the water.
The operation becomes smooth.

Next, FIG. 2 will be explained.

FIG. 2 is a longitudinal cross-sectional view showing another embodiment of the present invention, also in a water-stopped state, and the differences from the embodiment of FIG. 1 are as follows.

Note that the same parts as in the embodiment shown in FIG. 1 are given the same reference numerals.

The valve body 1 has an inlet 2 above the side wall, an outlet 3 in the middle, and a drain 4 below.
cylinders 6.7.8 are provided.

The piston 9 has three ring-shaped gaskets 12, 13, and 14 mounted on the outside in order from the bottom.

Furthermore, it has three joints, one-way sealing packing 1
Appropriate tightening force is applied to the piston 7, and the piston itself is prevented from loosening.

That is, extending the threaded portion to the lower part of the upper piston 9',
The middle piston 9″′ is inserted through the one-way sealing packing 17.
After applying an appropriate tightening force, the lower piston 9'' is tightened and fixed, so that the one-way sealing packing 17 is not subjected to excessive deformation.

The one-way sealing packing 17 has a downward protrusion 17' at the tip of the root to prevent it from shifting laterally.

The upper piston 9' is provided with a communication hole 15 and a communication horizontal hole 16,
The lower piston 9'' is similar to the embodiment shown in FIG. 1 in that it has a communication hole 15', but the lower part of the communication hole 15' is expanded to form a valve seat 21, and a ball valve 22 is formed in the lower piston 9''. is accommodated, and a roll pin 23 prevents the ball valve 22 from separating from the piston 9.

An O-ring 24 is attached to the lower end of the upper piston 9' to prevent water from the inlet 2 from directly entering the communication holes 15, 15'.

Further, the lower part of the ring-shaped packing 13 is made into a narrow diameter part 10,
A conduction path 18 is formed between the cylinder 7 and the cylinder 7.

The figure shows a water stop state, but when a faucet or the like is opened from this state, the water from the inlet 2 flows into the conduction path 18 as in FIG. and flows from the outlet 3 to the faucet side.

Even when negative pressure occurs on the main pipe side, as in the embodiment shown in Fig. 1,
Since the one-way sealing packing 17 closely contacts the cylinder 7 and blocks the flow of water from the outlet 3 to the inlet 2, no backflow occurs.

When draining water from the downstream piping, next time use piston 9.
It is best to lower the ring-shaped packing 13 to close the cylinder 7 to block the water from the inlet 2, and then the ring-shaped packing 12 separates from the cylinder 6 and the water in the downstream pipe is drained. It is discharged underground from mouth 4.

At this time, the water on the outflow port 3 side tries to rise into the pipe 19 through the communication holes 15' and 15, but the water flow instantly causes the ball valve 22 to rise and block the valve seat 21, which prevents the water from flowing into the pipe 19. Water never reaches within 19.

When the piston 9 is raised to open the valve, the ball valve 22 is disengaged from the valve seat 21, so negative pressure is generated at the lower end of the piston 9 and sewage is sucked from the drain port 4. Not at all.

Other operating modes are similar to those in FIG.

Note that the one-way sealing packing 17 is made of soft rubber.
It is advantageous in terms of flow rate to make the tip part as long and thin as possible.

This is especially true at low pressures.

The present invention has been described above with reference to the embodiments shown in FIGS. 1 and 2, but the one-way sealing packing 17 is basically L-shaped as in the embodiment shown in FIG. If so, it makes no difference to change the shape a little, and it is also possible to make the shape like the embodiment shown in FIG. 2 and install it with less tightening force by the piston, or without tightening it.

In addition, the shape of the valve body 1 may be changed as appropriate, such as by changing the positional relationship of the inlet, outlet, and drain, and the shape of the piston 9, the number of seals used, or the location where the piston is divided may be changed accordingly. or change the connection method as appropriate,
The design may be changed without departing from the gist of the present invention, such as by variously changing the method of attaching the one-way sealing packing to the piston.

As described above, in this invention, there is no need to install a separate check valve in the middle of the piping, so the construction work is simplified, and a one-way sealing packing that functions as a check valve is attached to the piston. Therefore, the one-way sealing packing can be easily repaired and inspected by pulling out the piston, and since the spring can be omitted, a large amount of water can be obtained especially at low pressure. Moreover, it has a very simple structure and is a low-cost antifreeze. Water taps can be provided.

[Brief explanation of the drawing]

FIG. 1 is a longitudinal cross-sectional view showing one embodiment of the present invention in a water-stopped state, and FIG. 2 is a longitudinal cross-sectional view showing another embodiment of the invention, also in a water-stopped state. 1...Valve body, 2...Inflow port, 3...
... Outlet, 4... Drain port, 5, 6, 7.
8...Cylinder, 9...Piston, 1
0...Small diameter part, 11, 12, 13.14...
...Ring-shaped packing, 15.15'...Communication hole, 17...One-way sealing packing, 18.
... Conduction path.

Claims (1)

[Scope of utility model registration request] The valve body has an inlet, an outlet, and a drain on the side wall, and has a cylinder inside, and the required number of ring-shaped packings that slide on the cylinder are attached to the outer periphery, and the valve body has a communication hole inside. In an antifreeze faucet in which a piston moves up and down to shut off water and drain water, the piston has at least two joints, and a ring is provided to cut off the inlet and the outlet, and the outlet and the drain. A narrow diameter part is provided between the shaped packings to form a conduction path that serves as a water flow path between the inlet and outlet ports, and the tip is expanded, basically L-shaped. A valve structure for a backflow prevention type antifreeze faucet, characterized in that a one-way sealing packing is fixedly attached between the narrow diameter portions of the piston.