JPS5915794Y2 - Pressure vessel check and low pressure outflow prevention valve - Google Patents

Description

[Detailed Description of the Invention] The present invention relates to a check and low-pressure outflow prevention valve interposed in a delivery hole of a main valve attached to a pressure vessel such as a gas cylinder.

This check and low-pressure outflow prevention valve is designed to prevent fluids from flowing into the pressure vessel from the outlet port of the main valve, and then the contents will be sent out and the pressure vessel will be left with the main valve open. This is provided to prevent water, dust, etc. from entering during the event.

By preventing the purity of the contents from decreasing due to these impurities, it is also possible to reduce the cost of filling the contents by omitting the vacuum work and gas replacement work that are required when refilling the contents. This is one of the reasons for providing an outflow prevention valve.

The inventor developed a non-return and low-pressure outflow prevention system that allows the valve to be forcibly opened by simply pushing a rod-shaped jig through the outlet of the delivery hole of the main valve, and to return to the closed state by simply removing the jig from the delivery hole. He was the first to invent a valve (Japanese Patent Application No. 89848/1989).

As shown in FIG. 4, this invention forms a valve chamber 72 with a larger diameter than the starting end 71 at the middle part of the outlet hole 70 of the main valve, and connects the valve chamber 72 and the outlet hole 70. Termination part 73
An outer passage 75 is provided concentrically with the outer end wall 74 that partitions the
is provided through the valve seat 7 at the periphery of the inner end of the outer passage 75.
6, a guide cylinder 79 is recessed in the outlet side end face of the spring seat 78 which is received by the inner end face 77 of the valve chamber 72, and the outlet side end face of the piston 80 is fitted into the cylinder 79 so as to be able to move forward and backward. 81 is concentric with this and has a smaller diameter valve 82
A valve-closing spring 84 is installed in a spring chamber 83 defined by a piston 80 inside the cylinder 79 so that the valve element 82 can be pressed against the valve seat 76, and the outer end wall 74 A valve opening pressure receiving surface 85 disposed in a pressure receiving chamber 85 formed between the spring receiving seat 78 and the opening pressure receiving surface 85 is formed by the outlet side end surface 81 of the piston 80 remaining around the valve element 82, and the spring receiving seat When the internal pressure communicating with the starting end 71 of the delivery hole 70 through the inner passage 87 formed between the peripheral wall of the valve chamber 78 and the peripheral wall of the valve chamber 72 is equal to or higher than a predetermined minimum allowable outflow pressure, the valve element 82 moves away from the valve seat 76. The valve is configured to be opened by being pulled apart, and further, with the valve element 82 being received by the valve seat 76,
The outer passage 75 and the spring chamber 83 are connected to each other through a communication hole 88 provided through the valve element 82 and the piston 80,
The valve element 82 is configured to be pressed against the valve seat 76 by the differential pressure between the pressure applied to the outer end surface 81 of the valve element 82 and the internal pressure of the spring chamber 83 applied to the piston 8o, and by the elasticity of the valve closing spring 84. .

However, according to the invention, the relative position between the outer end wall 74 and the spring seat 78 is determined by receiving the outer end wall 74 on a receiving surface 89 formed on the peripheral wall of the delivery hole 70. Therefore, depending on the fit of the outer end wall 74 and the spring seat 78, their relative positions may be distorted, and the minimum allowable outflow pressure may not be set accurately. Since the spring 84, piston 80, valve element 82, and outer end wall 74 are assembled into the delivery hole 70 one by one, there is a drawback that the assembly work becomes complicated.

In addition, unless they are installed in the delivery hole 70, the performance as a check and low pressure outflow prevention valve cannot be tested, so especially after replacing or repairing a malfunctioning check and low pressure outflow prevention valve. In the performance test, the main valve must be removed from the pressure vessel, which has disadvantages such as the risk of contamination of the pressure vessel with impurities.

In order to eliminate the above-mentioned drawbacks of the above-mentioned invention, the present invention has a concentric cylindrical connecting wall extended from the peripheral edge of the inner end surface of the outer end wall attached to the delivery hole, and the inner circumference of the connecting wall. By screwing the spring seat onto the surface and incorporating the valve/valve closing spring into the space formed by the inside of the connecting wall and the spring seat,
Each part inserted into the delivery hole forms a check and low-pressure outflow prevention valve in the form of an integrated cassette, and the cassette can be easily attached and removed from the delivery hole, just like attaching and removing a single bolt. At the same time, the performance of the cassette can be tested before it is assembled into the main valve, and at least one part of the connecting wall extending from the outer end wall is cut out along its entire length to connect the inner passage to the circumferential surface of the valve chamber. A relative position defining means having a protrusion is formed between the spring receiver and the outer end wall, and a portion of the protrusion is located between the inner end surface of the outer end wall inside the connecting wall and the outlet side end surface of the spring receiver. The piston is positioned so as to protrude into the reciprocating region of the valve pressure receiving surface, and a portion corresponding to the protrusion of the relative position determining means on either the curved surface portion of the piston on the valve opening pressure receiving surface side and the outer end wall opposing thereto. A recess is formed in the axial direction of the piston to form a rotation prevention part of the piston, and when the protrusion of the relative position determining means is received in this rotation prevention part, the valve element can come into contact with the valve seat. By configuring the valve so that it can be held in an open state by receiving a protrusion on the wall outside the detent assembly, the minimum allowable outflow pressure of the cassette-shaped check and low-pressure outflow prevention valve is reduced. The present invention is characterized in that settings can be easily performed and the valve can be easily and reliably held in the open state when refilling the cylinder.

Hereinafter, embodiments of the present invention will be described based on the drawings.

As shown in FIG. 1, a main valve chamber 5, a take-out hole 6, and a delivery hole 7 are formed inside the valve box 4 of the main valve 3 fixed to the outlet port 2 of the gas cylinder 1. The main valve 10 is accommodated by the rotation of the rotating stem 8 and moved toward and away from the main valve seat 9.

The middle part or the end part of the delivery hole 7 is formed to have a larger diameter than the starting end part 11, and a valve chamber 12 is formed in the middle part.

A check and low pressure outflow prevention valve cassette 13 is screwed into this valve chamber 12 .

The cassette case 14 of the cassette 13 consists of a holder case 15 and a spring seat 16, as shown in FIGS. 2 and 3.

The holder case 15 has the valve chamber 12 and the terminal end 1 of the delivery hole 7.
7 and a connecting wall 20 extending concentrically from the peripheral edge of the inner end surface 19 thereof.

Reference numeral 21 denotes an outer passage provided concentrically through the outer end wall 18;
A valve seat 22 is formed on the circumferential surface of the rear end of this valve.

The spring receiving seat 16, which is screwed into the inner circumferential surface 23 of the connecting wall 20, is formed with a guide cylinder 25 recessed concentrically from the outlet end surface 24 thereof. Possibly a piston 26 is fitted inside.

A valve element 27, which is concentric with the piston 26 and has a smaller diameter than the piston 26, is protruded from the outlet end of the piston 26.

The valve element 27 is pressed against the valve seat 22 by a valve-closing spring 29 housed in a spring chamber 28 in which the guide cylinder 25 is partitioned by a piston 26 (FIG. 2).

A pressure receiving chamber 30 is formed inside the cassette case 14 between the outer end wall 18 and the spring seat 16, and this pressure receiving chamber 30
A valve-opening pressure receiving surface 31 for urging the valve element 27 and the piston 26 to open in response to internal pressure is formed by the outlet side end surface of the piston 26 remaining around the valve element 27.

The connecting wall 20 of the holder case 15 is notched along its entire length at two locations deviating from each other by 180 degrees in the circumferential direction.
1 is formed.

With this configuration, when the internal pressure of the pressure receiving chamber 30 is low pressure below the minimum allowable outflow pressure, the valve closing spring 2
At 9, the valve 27 is pressed against the valve seat 22 to prevent the contents of the cylinder 1 from flowing out and impurities from entering the cylinder 1.

A spring pin 33 is implanted in the inner end surface 19 of the outer end wall 18, and a portion 34 of the pin 33 protruding from the inner end surface 19 serves as a spacer that defines the proper screwing amount of the spring seat 16 into the holder case 15. He plays 34 roles.

That is, by screwing the spring seat 16 into the holder case 15 until the outlet side end surface 24 of the spring seat 16 is received by the tip end surface 35 of the pin 33, the valve formed on the spring seat 16 and the outer end wall 18 is removed. A relative position with the seat 22 is defined.

When the pin 33 is arranged on the radius passing through the back passage 32 of the outer end wall 18, the pin 33 can be seen through the back passage 32 from the outside of the cassette case 14, so the spring seat 1
The advantage is that it can be clearly determined whether or not 6 is screwed in to the proper depth.

In addition, when the spacer 34 is formed by the pin 33 as described above, the shape of the holder case 15 can be simplified, for example.
The advantage is that it can be easily and inexpensively manufactured.

A communication hole 36 that communicates between the outer passage 21 and the spring chamber 28 in a state where the valve element 27 is received by the valve seat 22 is connected to the valve element 2.
7 and the piston 26, and is fitted onto the inner end of the piston 26.
and the circumferential surface of the guide cylinder 25, and another O-ring 38 fitted onto the middle part of the valve element 27 connects the valve element 27 and the valve seat 22.
Seal the space between each.

As a result, when the valve element 27 is pulled away from the valve seat 22, the spring chamber 28 becomes a negative pressure state due to the ejection action of the contents of the cylinder flowing out into the outer passage 21, and this negative pressure causes the valve closing spring 29 to The open state in which the valve element 27 moves away from the valve seat 22 is maintained.

When the internal pressure of the rim pressure receiving chamber 30 is lower than the minimum allowable outflow pressure that causes the outflow speed of the contents to be slower than a predetermined speed, or when the internal pressure of the rim pressure receiving chamber 30 is
When the pressure at the terminal end 17 of the valve is higher than that of the pressure receiving chamber 30, the ejecting action of the contents is weakened or eliminated, and the pressure applied to the outlet end surface 39 of the valve element 27 and the spring chamber 28 acting on the piston 26 are reduced. The valve element 27 is pressed against the valve seat 22 by the pressure difference between the internal pressure of the cylinder 1 and the elasticity of the valve closing spring 29.
backflow is prevented.

Note that one side of the piston 26 is cut out from the outlet end to the middle, and the cutout side surface 40 forms a rotation preventing surface that is received on the outer peripheral surface of the spacer 34.

As shown in FIG. 3, the valve element 27 and the piston 26 are pushed into the fully open position where the rear end surface 41 of the piston 26 is received by the bottom surface 42 of the guide cylinder 25 using a rod-shaped jig (not shown), and the cassette By rotating the phase with respect to the case 14 by 180 degrees, the valve opening pressure receiving surface 31 is positioned on the back side of the pin 33, and then by removing the jig, the valve opening pressure receiving surface 31 is received by the pin 33, and the valve opening pressure receiving surface 31 is received by the pin 33 and reversed. The structure is such that the stop/low pressure outflow prevention valve can be maintained in an open state (double-dashed line diagram).

Reference numeral 43 indicates a notched end surface of the piston 26, which also serves as a valve opening pressure receiving surface.

Reference numeral 44 denotes another O-ring fitted onto the outlet end of the holder case 15, which allows the holder case 15 and the valve chamber 12 to be connected to each other.
The space between the outer surface and the surrounding surface is sealed.

Reference numeral 45 denotes a hexagonal hole for engaging a hexagonal wrench (not shown), which is formed in the middle of the outer passage 21.

As explained above, in the present invention, a cylindrical connecting wall 20 is extended concentrically from the peripheral edge of the inner end surface 19 of the outer end wall 18, and a spring receiver is provided on the inner peripheral surface 23 of the connecting wall 20. The seat 16 is screwed together, and a piston 26, a valve element 27 formed integrally with the piston 26, and a valve closing spring 29 are incorporated therein to form a so-called check and low pressure outflow prevention valve cassette. Since the valve is configured to be screwed into the delivery hole 7 of the main valve 3, the work of assembling the check and low pressure outflow prevention valve into the main valve 3 is as easy as installing and removing a single bolt. Can be done.

Further, the relative position defining means having the protrusion 33 is attached to the outer end wall 18.
The outer end wall 18 and the spring receiver are positioned between the rear end surface 19 on the inner side of the connecting wall 20 and the rising side end surface 24 of the spring receiver 16, and the outer end wall 18 and the spring receiver Since the relative position with respect to the seat 16 can be specified, the minimum elasticity of the valve closing spring 29 or the minimum allowable outflow pressure of the check and low pressure outflow prevention valve can be set accurately. The simple work of simply screwing in the seat 16 is sufficient.

Furthermore, whether or not this pressure setting was performed correctly is determined by the main valve 3.
The test can be carried out by screwing the cassette-shaped test hole into a test hole formed in the same manner as the delivery hole 7, and there is no need to remove the main valve 3 from the pressure vessel 1. The contamination of 1 with impurities can be completely eliminated.

Moreover, the protrusion 33 of the relative position defining means 34 is positioned such that a part of it protrudes into the advance/retreat area of the valve-opening pressure receiving surface 31 of the piston 26, and the protrusion 33 of the relative position defining means 34 is positioned so as to be opposed to the circumferential surface portion of the valve-opening pressure receiving surface of the piston 26 on the side of the valve-opening pressure receiving surface. Since the piston rotation prevention portion is formed by placing four positions corresponding to the projections 33 on either one of the outer end walls in the piston axial direction, the piston does not rotate when the projection 33 is inserted into the rotation prevention portion. 26 can be held in a state where the valve can be opened and closed, and the valve can be easily and reliably held in the open position when the protrusion 33 is in contact with the valve opening pressure receiving surface outside the detent assembly.

As a result, with the check and low pressure outflow prevention valve of the present invention, refilling the pressure vessel with gas can be easily performed.

[Brief explanation of drawings]

The drawings show an embodiment of the present invention, and FIG. 1 is a longitudinal sectional front view of the main valve, FIG. 2 is a sectional view taken along the line A-A in FIG. 1 in the closed state, and FIG. 3 is FIG. 1 in the open state. The sectional view taken along the line A-A, FIG. 4, is a diagram corresponding to FIG. 2 of the conventional example. 1...Pressure vessel, 2...Outlet port, 3.
...Main valve, 7...Outlet hole, 11...
...Starting end of the delivery hole, 12... Valve chamber, 16...
... Spring seat, 17 ... End of delivery hole,
18... Outer end wall, 19... Rear end surface of outer end wall, 20... Connecting wall, 21... Outer passage, 22... ... Valve seat, 23 ... Inner peripheral surface of connecting wall, 24 ... Outlet side end surface of spring seat, 2
5... Guide cylinder, 26... Piston, 27... Valve, 28... Spring chamber,
29... Valve closing spring, 30... Pressure receiving chamber,
31... Valve opening pressure receiving surface, 32... Back passage, 33... Protrusion (pin), 34...
Relative position defining means, 36...Communication hole, 37, 3
8... Sealing means, 39... Valve outlet side.

Claims (1)

[Scope of utility model registration request] A valve chamber 12 is formed in the middle of the outlet hole 7 of the main valve 3 which is fixed to the outlet port 2 of the pressure vessel 1, and an outer end wall 18 is screwed to the outlet side end of the valve chamber 12 in an airtight manner. A valve seat 22 is formed around the inner end of the outer passage 21 which is concentrically provided through the outer end wall 18, and an outlet side end surface 24 of the spring seat 16 inserted into the inner part of the valve chamber 12. A guide cylinder 25 concentric with this is recessed, and a valve 27 concentric with the piston 26 and having a smaller diameter than the piston 26 is inserted from the outlet side end of a piston 26 fitted into the cylinder 25 so as to be able to move forward and backward. a spring chamber 2 that is partitioned by the piston 26 inside the cylinder 25;
A valve-closing spring 29 for urging the valve element 27 and the piston 26 to move forward is housed in the pressure receiving chamber 8, and the valve closing spring 29 is located inside the pressure receiving chamber 30 formed between the outer end wall 18 and the spring seat 16. 3
A valve-opening pressure receiving surface 31 that urges the valve element 27 and the piston 26 to open in response to an internal pressure of 0 is formed by the exit side end surface of the piston 26 remaining around the valve element 27, and the pressure receiving chamber 3
0 and the starting end 11 of the delivery hole 7 are provided, and a relative position defining means 34 is provided to define the relative position of the outer end wall 18 and the spring seat 16. A communication hole 36 that connects the outer passage 21 and the spring chamber 28 in the closed state received by the valve 22 is connected between the valve element 27 and the piston 26, and the piston 26 and the circumferential surface of the guide cylinder 25 communicate with each other. In a pressure vessel check and low pressure outflow prevention valve provided with a sealing means 37 for sealing between the valve element 27 and the valve seat 22 in a closed state, and a sealing means 38 for sealing between the valve element 27 and the valve seat 22 in a closed state. A concentric cylindrical connecting wall 20 is extended from the peripheral edge of the inner end surface 19 of the outer end wall 18, and the spring receiver 16 is screwed onto the inner circumferential surface 23 of the connecting wall 20. A valve element 27 and a valve-closing spring 29 are assembled into the space formed by the spring seat 16 and the inner passage 32 is connected to the circumferential surface of the valve chamber 12 by cutting out at least one part of the connecting wall 20 along its entire length. The protrusion 33 is formed between the spring seat 16 and the spring seat 16.
A portion of the protrusion 33 is placed between the inner end surface 19 of the outer end wall 18 on the inner side of the connecting wall 20 and the outlet end surface 24 of the spring seat 16, so that a portion of the protrusion 33 is connected to the opening pressure receiving surface of the piston 26. 31, and the protrusion 33 of the relative position defining means 34 on either one of the circumferential surface portion of the piston 26 on the side of the valve opening pressure receiving surface 31 and the outer end wall 18 facing thereto. A corresponding portion is recessed in the axial direction of the piston 26 to form a rotation prevention portion of the piston 26, and the protrusion 3 of the relative position defining means 34 is inserted into this rotation prevention portion.
3 is received, the valve element 27 can come into contact with the valve seat 22, and the projection 33 is received on the wall surface other than the rotation stop part, so that the valve element 27 can be held in an open state. A pressure vessel check and low pressure outflow prevention valve characterized by: