JP2000145994A - Back flow preventing indoor stop cock for cold district - Google Patents

Abstract

PROBLEM TO BE SOLVED: To shorten a fitting span so as to facilitate piping work in a narrow space by disposing an operation rod to which a check valve body also serving as water stop coaxially without separately installing a stop valve and a check valve in series, and lifting the operating rod to separate the check valve main body from the valve seat at the time of draining. SOLUTION: When a faucet is opened, the water pressure of the check valve body 29 overcomes the frictional force of a sealing packing 32, so that while a check valve body 29 compresses a nonreturn spring 30, it rises along a small diameter part 23 to enter the water passing state. When a handle 19 connected to the operating rod 17 is rotated, a spindle 10 having a male side detent part 11 fitted with a female side detent part 18 is rotated, and simultaneously lowered by an operating male screw 7 so that the lower end part abuts on a check valve body 29 to enter the cutoff state. At the time of draining in winter, the handle 19 is lifted to raise the operating rod 17, and the check valve body 29 locked on a stop ring 24 is raised to enter the drain sate. That is, since the a check packing 3 is separated from the valve seat 4, water is discharged to prevent a freezing accident.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an indoor water stopcock having a backflow preventing function for use in cold regions.

[0002]

2. Description of the Related Art Hitherto, for example, Japanese Patent Application No. Hei 6-3029 by the same applicant has been proposed for this type of apparatus and has been put to practical use. However, in the above-mentioned thing, since the valve that shuts off water and the check valve are separately provided in series, the installation span is inevitably long, such as around the indoor boiler,
When installed in a narrow space, there is a defect that piping work is very difficult, and improvement has been desired.

[0003]

SUMMARY OF THE INVENTION In view of the above, it is an object of the present invention to provide a backflow prevention type indoor water stopcock for a cold district, which has a mounting span as short as possible.

[0004]

Therefore, in the present invention, the check valve is stopped by a spindle provided on the same axis as the check valve so that the check valve and the check valve are mounted separately without being connected in series. The span is shortened, and at the time of drainage, the operating rod, which is housed in the spindle and is connected to the check valve at the lower end, is raised to disengage the check valve from the valve seat. By acting downward water pressure,
The automatic return is performed.

[0005]

DESCRIPTION OF THE PREFERRED EMBODIMENTS A check spring is provided in a valve box provided with an inflow port formed on the same axis, an upward valve seat inclined toward the outflow port at an intermediate portion of the outflow port, and a female screw for operation above the valve seat. A check valve that closes the valve seat by being pressed by the valve, and a spindle that has a male screw for operation that is screwed into the female screw for operation, and further has an operating rod inside the spindle that connects the check valve to the lower end. And a pressure receiving chamber and an air chamber are formed by the spindle and the operating rod, and the operating rod is held downward by a downward water pressure acting on the pressure receiving chamber. as,

[0006] The upper lid connected to the upper end of the valve box may be omitted, and screws or the like may be screwed into the valve box to serve as a stopper for raising the spindle. The female screw for operation is provided on the upper lid instead of the valve box. Is also possible.

A detent is formed inside the handle connected to the operation rod and at the upper end of the spindle so that the handle is fitted to the spindle so that it cannot rotate and can move up and down. The role may be given to the user. Further, it is also possible to connect the handle to the spindle and make the operation stick protrude from the upper end of the handle so that only the operation stick is pulled up without operating the handle when draining water.

In the spindle, an air chamber forming member for forming an air chamber is inserted from the lower end of the spindle so as to be easily assembled and disassembled. However, the air chamber forming member is formed integrally with the spindle. At the upper part, the spindle may be disassembled into two parts.

[0009]

FIG. 1 shows an embodiment of the present invention.
Is a valve box having an inlet 2 at the left end and an outlet 3 at the right end on the same axis, and an upward valve seat inclined to the outlet 3 side in the middle part in consideration of drainage and low loss head. 4, a sealing gasket 5 is mounted above, and an operating female screw 6 is formed further above.

[0010] Inside the valve box 1, there is provided an external male screw 7 for screwing with the internal female screw 6, and an air hole 8 is drilled above it.
The upper lid 9 connected to the upper end of the valve box 1 accommodates a spindle 10 serving as a stopper when ascending, and the upper end is protruded upward from the cap 9 to provide several flat surfaces to form the male-side detent portion 11. . Further, a small-diameter pressure-receiving packing 12 is attached to the upper end of the spindle 10, and a cylinder 13 is provided below the small-diameter pressure-receiving packing 12.

A lower portion of the air hole 8 in the spindle 10 is formed to have a slightly larger diameter than the cylinder 13 and an inner O-ring 1 is formed therein.
4. Position the air chamber forming member 16 to which the outer O-ring 15 is mounted.

Reference numeral 17 denotes an operation rod for moving up and down in the spindle 10. A handle 19 having a female detent part 18 fitted to the male detent part 11 is connected to the upper end thereof. 20, a large-diameter pressure receiving portion 21 is further provided thereunder, and a large-diameter pressure receiving packing 22 is mounted thereon.

A small diameter portion 23 penetrating the air chamber forming member 16 is formed below the large diameter pressure receiving portion 21, and a retaining ring 24 is attached to a lower end thereof. The small-diameter portion 23 to which the inner O-ring 14 is in close contact is referred to as a small-diameter pressure receiving portion 25.

A pressure water introduction hole 26 communicating with the upper end of the large-diameter pressure-receiving packing 22 from the lower end is formed in the operation rod 17.
A pressure receiving chamber 27 is formed between the pressure receiving chamber 27 and the spindle 10. Further, the air chamber 2 is disposed between the large-diameter pressure receiving portion 21 and the air chamber forming member 16.
8 is formed and communicates with the air hole 8.

Reference numeral 29 denotes a check valve body which is pressed by a check spring 30 having the air chamber forming member 16 as a pedestal so that the check packing 31 is brought into close contact with the valve seat 4 to stop water. Part 2
A sealing packing 32 that is in close contact with 3 is mounted.

The figure shows a state in which a faucet (not shown) at the end of the outflow-side pipe is closed, that is, a water stop state. The operation rod 17 is introduced into the pressure receiving chamber 27 through the pressure water introduction hole 26. The air chamber forming member 16 receives the downward force obtained by subtracting the water pressure based on the area of the small-diameter pressure receiving section 25 from the water pressure based on the area difference between the large-diameter pressure receiving section 21 and the small-diameter pressure receiving section 20. are doing.

When the faucet is opened from this state, the check valve body 29 is opened.
The pressure rises with the small-diameter portion 23 as a guide while compressing the check spring 30 by overcoming the frictional force of the sealing packing 32 by water pressure, and enters a water-permeable state. Spin up to the maximum 10
It contacts the lower end.

When a negative pressure is generated on the main pipe side due to water cutoff or the like in the water flowing state, the check valve body 29 is immediately pressed by the check spring 30 and the check packing 31 is moved to the valve seat 4. The sealing gasket 32 and the sealing packing 32 prevent backflow of water in the outflow-side pipe.

When it is desired to stop the water, when the handle 19 connected to the operation rod 17 is rotated from the state shown in the figure, the spindle 10 in which the male detent part 11 is fitted to the female detent part 18 also rotates, At the same time, it is lowered by the operating male screw 7,
The water is stopped when the lower end portion is in contact with the check valve body 29. If stopped before contact, the rising distance of the check valve body 29 is limited, and the flow rate can be freely adjusted.

In the winter, when water is to be drained, an antifreeze water tap (not shown) installed in the upstream pipe of the present invention in a flowing state.
, The handle 19 is lifted, and then the operating rod 17 is also lifted and the retaining ring 2 is lifted.
4 and the check valve body 29 rises to the drained state shown in FIG.

That is, since the check packing 31 is detached from the valve seat 4, the water in the pipe and the water stopcock is discharged from the antifreeze water tap into the ground, and a freezing accident may occur. Can be prevented. At this time, if the rising distance of the check packing 31 is small, a water film is formed between the valve seat 4 and the check packing 31,
When the spindle 10 is lowered by adjusting the flow rate, it is desirable that the spindle 10 be fully opened because there is a possibility that water will not come out even if the antifreeze water tap is opened after freezing.

Next, when water is re-flowed, that is, when the antifreeze water tap is opened and water is discharged, the pressure receiving chamber 2 passes through the pressure water introduction hole 26.
The operation rod 1 is actuated by the above-described downward water pressure acting on the operation rod 7.
7 descends while discharging the air in the air chamber 28 from the air hole 8, and when the faucet is closed, the check valve body 29 is also pushed down by the check spring 30, and returns to the state of FIG. .

At the time of installation, a test pump is often used to apply pressure from the end of the pipe on the outflow side to check whether or not the entire pipe is leaking. There was a drawback that it was not possible to withstand pressure.

However, in the present invention, the handle 19
By lifting the operating rod 17 and inserting a spacer between the handle 19 and the upper lid 9, the check valve body 29
Since the state of FIG. 2 is maintained, the pressure test of the entire pipe can be performed.

FIG. 3 shows another embodiment of the present invention. As compared with the embodiment shown in FIGS.
Does not penetrate the check valve body 29, and the pins 33 inserted into the small-diameter portion 23 are locked in the vertical grooves 34 provided on both sides of the check valve body 29, and are connected so as to be movable up and down. 1 can be omitted. Therefore, the pressure water introduction hole 26 is not provided in the operation rod 17, but is formed in the valve box 1, and the pressure inlet and the pressure receiving port are formed through the communication hole 35 formed in the spindle 10. Room 2
7 is conducted, and the air hole 8 is not provided in the spindle 10 but provided inside the operation rod 17.

Since the sealing gasket 32 can be omitted as compared with the one shown in FIG. 1, the function as a check valve and a water stop valve is further enhanced, and the check valve body 29 is not rotated by the pin 33. This has the advantage that the causes of vibration and wear when passing water can be eliminated.

[0027]

As described above, according to the present invention, while having the functions of the indoor stopcock such as flow control and water stoppage as it is, a backflow prevention function capable of draining water is added. The water stop valve and the check valve are not installed separately and in series in the mounting axis direction, but the operating rod connecting the check valve that doubles as the water stop is arranged on the same axis as the check valve to drain water. In some cases, the operation rod is lifted to release the check valve body from the valve seat, so that the installation span is shortened, and there is an effect that piping work in a narrow place becomes easier.

[Brief description of the drawings]

FIG. 1 is a longitudinal sectional view showing a water stop state according to an embodiment of the present invention.

FIG. 2 is a vertical cross-sectional view of the above-described device in a drained state.

FIG. 3 is a longitudinal sectional view showing another embodiment of the present invention in a water stopped state.

[Explanation of symbols]

1 valve box 2
Inlet 3 Outlet 4
Valve seat 5 Sealed packing 6
Female thread for actuation 7 Male thread for actuation 8
Air hole 9 top lid 10
Spindle 11 Male detent 12
Small diameter pressure receiving packing 13 Cylinder 14
Inner O-ring 15 Outer O-ring 16
Air chamber forming member 17 Operating rod 18
Female side detent part 19 Handle 20
Small diameter pressure receiving part 21 Large diameter pressure receiving part 22
Large Diameter Pressure Packing 23 Small Diameter 24
Retaining ring 25 Small diameter pressure receiving part 26
Pressure water introduction hole 27 Pressure receiving chamber 28
Air chamber 29 Check valve 30
Check spring 31 Check packing 32
Seal packing 33 Pin 34
Vertical groove 35 Communication hole

Claims (1)

[Claims] 1. A valve box having an upward valve seat inclined toward the outlet at an intermediate portion between an inlet and an outlet formed on the same axis, and the valve seat is closed by being pressed by a check spring. A check valve body, a spindle that receives the rotational force of the handle and presses the check valve body with a screw to stop water, and is housed in the spindle so as to be movable up and down. The spindle is basically composed of an operating rod freely connected, and the spindle has a pressure receiving chamber for introducing pressurized water from an inflow port between a large-diameter pressure receiving portion of the operating rod and a small-diameter pressure receiving portion above the operating rod. An air chamber that opens to the atmosphere is formed between the large-diameter pressure receiving portion and the small-diameter pressure receiving portion below the pressure receiving portion, and when draining, the operating rod is raised, and a check valve body connected to the operating rod is provided as a valve seat. From the pressure receiving chamber when water is re-flowed. In the cold regions for backflow prevention type indoor water shutoff valve, characterized in that it was.