JPH0248520Y2 - - Google Patents

Description

[Detailed description of the invention] (a) Industrial application field This invention relates to a valve structure for a drain valve that drains water from pipes in cold regions.

(b) Conventional technology In cold regions, the water in water pipes often freezes during the winter, and as a countermeasure, water in the pipes is drained underground before going to bed to prevent tap water from freezing. .

Figure 1 shows how the drain valve is used. 1 is the valve body, 2 is the outer shell pipe, 3 is the water pipe, 4 is the riser pipe,
7 is a drain port, and 9 is a faucet, and when it is cold, the water in the riser pipe 4 is discharged into the ground from the drain port 7 by operating a handle 8 provided at the upper part of the outer jacket pipe 2. FIG. 2 is a front sectional view of the valve body 1 of a conventional water drain valve, showing an inlet 5, an outlet 6, and a drain 7.
A piston 10 is disposed within the valve body 1 having cylinders 17, 18, 19 and a valve seat 20 therein.
The piston 10 is equipped with O-rings 12, 13, 15 that seal water tightly corresponding to the cylinders 17, 18, 19 in order from the top, and a flat O-ring that seats on the valve seat 20 and seals water. I am wearing Patsukin 14. An outer shell pipe 2 is screwed onto the valve body 1, a shaft 11 is screwed onto the piston 10,
It is connected to a handle mechanism (not shown) provided above. FIG. 2 shows the water supply state, in which water enters from the inlet 5, passes through the outlet 6, passes through the riser pipe 4, and flows out to the faucet 9. At this time, piston 10
is at the top position, and O-ring 1 is attached to it.
3 is tightly water-sealed to the cylinder 18, so water from the inlet 5 does not flow to the drain 7.
Next, when the O-ring 15 enters the cylinder 19 below the valve seat in the process of lowering the piston 10 using the handle mechanism to drain water, the O-rings 13 and 15 enter the cylinder 18 and the cylinder 19 below the valve seat. At the same time, a tight water seal is created, and the water from the inlet 5 does not flow out to the drain port 7 nor the water from the riser pipe 4 flows to the drain port 7, i.e., a neutral state is created, preventing water leakage due to the halfway position of the piston 10. It is. When the piston 10 further moves down, the flat packing 14 immediately reaches the valve seat 20 in the valve body 1.
The ring 13 comes off from the cylinder 18, and the water from the riser pipe 4 passes through the side wall of the piston 10, flows to the drain port 7, and is discharged underground.Finally, the flat packing 14 seats on the valve seat 20, completely stopping the water. That's what I do.

(c) Problems that the invention attempts to solve In Fig. 2, when the piston 10 is lowered and the water from the inlet 5 is stopped by the O-ring 15,
As the ring 15 approaches the valve seat lower cylinder 19, the valve seat 20 is removed from above the valve seat lower cylinder 19.
The flow rate of the water flowing out increases near the area, and there is a part on the outside of the O-ring 15 where the pressure is lower than that on the inside of the O-ring 15, so a force that pushes out the O-ring 15 from the inside is generated, and the O-ring 15 pushes against the piston 10.
When the piston 10 protrudes from the O-ring groove, and the piston 10 goes down further, the cylinder 19 below the valve seat
This can cause the O-ring 15 to become damaged or break.

(d) Means for solving the problems In order to solve the problems of the valve structure of the conventional water drain faucet, the present invention adopts the structure shown below. Below, regarding the part numbers in the drawings to be explained, the same numbers are used for the same functions as conventional products.

In Fig. 3, an inlet 5, an outlet 6, and a drain 7 are arranged in order from the bottom, and the drain 7 is placed inside.
Cylinders 17 and 18 with the same diameter at the top and bottom and the inlet 5
There is a piston 10 that moves up and down within the valve body 1 forming a valve seat 20 and a cylinder 19 below the valve seat concentrically with the cylinders 17 and 18 between the drain port 7 and the drain port 6. O-rings 12 and 13 are fitted around the cylinders 17 and 18 located above and below the piston 10 for tight water sealing.
A flat part 24 seats on the valve seat 20 in the valve body 1 in a concave part at the tip of the valve body 1, and a valve seat lower cylinder 19 is located below the flat part 24.
The upper part of the water stop valve body 21 having a slightly larger diameter and a protrusion 23 that tightly seals against the cylinder 19 below the valve seat is inserted, and the inner surface of the water stop valve body 21 has a slight gap as shown in FIG. is provided, and only the upper surface 25 inside the water stop valve body 21 is fixed by a valve holder 22. The lower part of the valve holder 22 has a slit shape 26 so that the lower part of the protrusion 23 of the water stop valve body 21 partially wraps around the lower part of the protrusion 23 so that the lower part of the protrusion 23 of the water stop valve body 21 is not affected by the water flow from the inlet 5 side. The diameter of the lower portion of the valve holder 22 is slightly smaller than that of the cylinder 19 below the valve seat. An outer tube 2 is screwed onto the upper end of the valve body 1, and a shaft 11 is screwed onto the upper end of the piston 10, thereby connecting to a handle mechanism (not shown) provided above.

(E) Function In Fig. 4, the diameter of the lower part of the valve holder 22 is
Since it is made slightly smaller than the cylinder 19 below the valve seat, the water from the inlet port 5 is once throttled and most of the pressure head in the A section changes to a velocity head, and as a result, the pressure head in the A section and Since the C part becomes lower, the water stop valve body 21 is lowered due to the pressure from the B part.
The protrusion 23 can smoothly enter the cylinder 19 below the valve seat without protruding due to the force applied inward to the cylinder 19 and the water flow.

Furthermore, as shown in FIG. 5, when the protrusion 23 of the water stop valve body 21 tightly seals the cylinder 19 below the valve seat, the pressure at the outflow side B is reduced by the faucet 9 at the end of the riser pipe 4. Since there is no pressure, the pressure from the inlet 5 acts on the C section inside the water stop valve body 21, exerting a force that pushes the protrusion 23 outward, improving the tight water sealing performance.

(F) Effect of the invention When stopping the pressure from the inflow side 5, according to the invention, the increase in flow velocity due to the throttling condition is used inversely,
Eliminate damage and breakage of the water stop valve body 21 due to water stop,
The neutral state described earlier can be created, and since the close water sealing method using pressure is adopted, even if the diameter difference between the valve seat lower cylinder 19 and the protrusion 23 of the water stop valve body 21 is small. Water can be stopped. In other words, even if the protrusion 23 is used for many years and is worn out, it can still be used, and the period for replacing the water stop valve body 21 can be extended.

[Brief explanation of the drawing]

FIG. 1 is a schematic diagram showing how the drain valve is used. Second
The figure is a front sectional view of the valve body of a conventional product, showing the water supply state. FIG. 3 is a front sectional view of the valve body of the present invention, showing the water supply state. FIG. 4 is a front sectional view of the main parts of the product of the present invention, showing the state immediately before the water stops. FIG. 5 is a front sectional view of the main parts of the product of the present invention, showing the state immediately after the water has stopped. FIG. 6 shows a perspective view of the water stop valve body 21 of the present invention.

Claims (1)

[Scope of utility model registration request] An inlet 5, an outlet 6, and a drain 7 are arranged in order from the bottom, and cylinders 17, 18 of the same diameter are arranged above and below the drain 7, and a valve seat 20 and a valve seat are placed between the inlet 5 and the outlet 6. O-rings 12 and 13 are fitted around the cylinders 17 and 18 provided above and below the drain port 7 in the valve body 1 forming the lower cylinder 19 concentrically with the cylinder, and O-rings 12 and 13 are fitted around the cylinders 17 and 18, which form a lower cylinder 19 concentrically with the cylinder. The lower tip of the piston 10 is a water drain valve that allows water to flow and drain water by moving up and down the piston 10, which is seated on a seat 20 and a cylinder 19 below the valve seat, and is fitted with a flat packing 14 and an O-ring 15 for a tight water seal. A flat part 24 that seats on the valve seat 20 in the valve body 1 and a protrusion 23 having a slightly larger diameter than the valve seat lower cylinder 19 are integrated into the concave part, and a slight gap is provided between the lower part and the inner surface of the protrusion 23. A valve holder 22 having a slit-like shape 26
A valve structure of a drain valve comprising a water stop valve body 21 fixed by.