JPH0213817Y2 - - Google Patents

Description

[Detailed Description of the Invention] The present invention relates to a gas release prevention device attached to a container containing LP gas or other high-pressure gas, and particularly to a container valve with an overflow prevention device.

Conventionally, a container valve attached to a container containing high-pressure gas such as a flammable gas, a combustion-supporting gas, or a toxic gas is always opened when a regulator or piping is connected to the container. Therefore, if the downstream joint, regulator, or connecting pipe of the container valve breaks due to some external cause such as an earthquake or external shock,
There is a drawback that the contents may be ejected due to the pressure inside the container (cylinder). Therefore, some container valves are equipped with a gas release prevention means, and when a connecting pipe or the like is ruptured and the amount of discharge increases, the gas release prevention means is activated to shut off the gas. However, the discharge flow rate varies depending on the internal pressure of the container, and the internal pressure of this container varies depending on the external temperature of the container. Therefore, if the gap 3 between the valve port 1 of the gas release prevention means A and the check valve 2 is constant, There was a drawback that the amount of working fluid passing through the gap 3 increased significantly. For example, if the container content is 1
Kgf/cm ² , the working fluid flowing out from the gap 3 is about 2.5 Kg/H, as shown in FIG. Furthermore, when the internal pressure of the container reaches 15 kgf/cm ² , even though the gap 3 is constant, the working fluid passing through the gap is approximately 7.5 kgf/cm 2 .
Kg/H, and although it is the same gas release prevention device, it has a drawback that its operating range M is wide, such as 2.5 to 7.5 Kg/H. This was extremely dangerous because the amount of gas released from the container to the outside until it was shut off by the gas release prevention device varied significantly depending on the internal pressure of the container.

In order to eliminate such drawbacks, the present invention maintains the operating flow rate within a constant range even if the internal pressure of the container changes.The present invention consists of a connection part for connecting pipes on one side, a safety valve on the other side, In a valve having a threaded portion for connecting the container at the lower part thereof, and a handle connected to a valve body for opening and closing the valve port provided inside, the valve is provided in the primary passage communicating with the valve port. The holder accommodates an operating rod that moves up and down due to a pressure difference, and the operating rod narrows the gap between the check valve and the valve opening to maintain a constant operating flow rate.

Hereinafter, an embodiment of the present invention will be described with reference to the drawings. A threaded portion 12 for connecting a container (not shown) is formed on the outer periphery of the lower part of the valve body 11.
A tapered first valve port 14 with a small diameter is provided at the bottom of a valve chamber 13 with a slightly large diameter provided in the upper part of the operating rod 16, which has an on-off valve 15 at the bottom for opening and closing the first valve port 14. A handle 17 is attached to the upper part of the valve body 11, and a lid body 18 passing through the operating rod 16 is screwed onto the upper part of the valve body 11. A reversely tapered second valve port 20 is formed below the first valve port 14, and a primary passage 21 is formed in communication with the second valve port 20 to the lower end of the valve body 11. 22 is the primary side passage 2
1, and a connecting portion 19 for connecting piping is formed on one side of the valve chamber 13. A holder 25 is attached to the lower part of the primary passage 21, and a partition wall 27 having a small diameter hole 26 in the center projects from the middle part. Inside this holder 25, an upper chamber 28 is provided above the partition wall 27, and a lower chamber 29 is provided below, and a plurality of openings 30 are formed in the circumferential surface of the holder in communication with the upper chamber 28. Reference numeral 31 designates a sensor having a guide disk 32 in contact with the inner wall of the upper chamber 28 at its lower end, and a blind receiving hole 34 formed at its upper end. 35
is a valve rod whose lower end is accommodated in the accommodation hole 34 so as to be movable up and down; the intermediate portion thereof is formed with a plurality of guide pieces 36, 36 projecting in the radial direction; and the upper end thereof is connected to the second valve port 20. A seated check valve 37 is provided, and a spring 38 is installed around the valve rod 35 between the guide pieces 36, 36 and the upper end of the sensor 33. By lowering the valve 37, a gap 39 between the second valve port 20 and the check valve 37 can be widened. This second valve port 20 and the check valve 37 form a gas release prevention device A. Reference numeral 40 designates a piston having a large diameter portion 41 at its lower end that is in contact with the inner wall of the lower chamber 29, and this locking portion 4
A small-diameter portion 43 is formed at the upper part of 1 with a hooking step portion 42 interposed therebetween. This small diameter portion 43 is formed longer than the locking portion 41 so that it can protrude into the upper chamber 28 from the small diameter hole 26. In addition, the small diameter portion 43 and the large diameter portion 4
O-rings 44 and 45 are attached to the outer periphery of each of the holes 1 to improve airtightness with the small-diameter hole 26 and the lower inner wall, respectively. A lower cover 47 is attached to the lower end of the holder 25, and has a hole 48 in the center.
Further, a spring 49 is provided between the partition wall 27 and the large diameter portion 41 of the piston. In this way, the second valve port 20, the check valve 27, and the sensor 3
3. The overflow prevention device B is formed by the piston 40 which is urged by a spring 49 and whose pressure receiving surface S ₂ of the small diameter portion 43 and pressure receiving surface S ₁ of the large diameter portion 41 are different.

Next, to explain the operation of this embodiment, when the pressure P ₁ inside the container enters through the hole 48 of the lower lid and acts on the pressure receiving surface S ₁ of the large diameter portion of the piston 40, the load X on the large diameter portion 41 The equations =P ₁ and S ₁ hold true.
The pressure P ₁ enters into the upper chamber 28 through the opening 30 and acts on the pressure receiving surface S ₂ of the small diameter portion, and the equation of load Y=P ₁ , S ₂ of the small diameter portion 43 holds true. Here, S ₁ > S ₂
Therefore, X>Y, and the piston 40 in the lower chamber 29 rises when the internal pressure _P1 becomes stronger than the elastic force of the spring 49, and moves this small diameter portion 43 into the upper chamber 2.
8 and raises the sensor 33 and check valve 37 through the disc 32, thereby narrowing the gap 39 between the second valve port 20 and the check valve 37. In this way, by raising the check valve 37 in accordance with the rise in internal pressure, the gap 39 is narrowed, thereby reducing the amount of working fluid flowing out from the gap as shown in FIG. This maintains the operating range N, which is significantly narrower than the conventional one. In theory, it is possible to make this operating range N a parallel line, that is, constant, but it would increase the cost due to adjustments, additional parts, etc., so to prevent this cost increase as much as possible, it is possible to make it a narrow line as shown in Figure 7. I was able to accomplish a range of things.

As described above, since the present invention further adds a gas overflow prevention device to the gas prevention device, even if the internal pressure of the container changes due to changes in the environment outside the container, the gap between the second valve port and the check valve can be adjusted to prevent the pressure from changing. Since it can be narrowed in proportion to the container, the working fluid can be kept constant regardless of changes in the internal pressure of the container, making it extremely safe to handle.

[Brief explanation of the drawing]

The drawings show an embodiment of the present invention: Fig. 1 is a longitudinal sectional view of the whole, Fig. 2 is an enlarged sectional view of the main part, Fig. 3 is a front view of the operating rod, and Fig. 4 is a partial view of the rod. FIG. 5 is an explanatory diagram showing the operating flow rate of the present embodiment, FIG. 6 is a sectional view of a conventional gas release prevention device, and FIG. 7 is an explanatory diagram showing the operating flow rate of the conventional example. 11 is a valve body, 14 and 20 are valve ports, 21 is a primary passage, 25 is a holder, 37 is a check valve, 39 is a gap, and 40 is a piston.

Claims (1)

[Scope of utility model registration request] It has a connecting part for connecting pipes on one side, a safety valve on the other side, a threaded part for connecting the container at the bottom, and a handle connected to a valve body that opens and closes the valve opening provided inside. In the valve, a piston that moves up and down due to a pressure difference is housed in a holder provided in the primary passage communicating with the valve port, and this piston narrows the gap between the check valve and the valve port to adjust the operating flow rate. A container valve with an overflow prevention device that maintains a constant value.