JPH06159599A - Opening/closing valve for high pressure gas - Google Patents

Abstract

PURPOSE:To provide an opening/closing valve for high pressure gas of extremely high airtightness. CONSTITUTION:The upper side of a container valve main body 2 forms a cylinder part 21, and a bonnet 4 is screwed into the upper end part of the cylinder part 21 so that the cylinder part is covered from outside. A recessed part 5 is formed on a connection surface 51 of the bonnet 4 with the cylinder 21, and a gasket 7 longer than the depth of the recessed part 5 is provided in the recessed part 5. The outer peripheral part of the gasket 7 is extended to and is thereby interposed between the bonnet 4 and the connection surface W the cylinder part 21 by sandwiching the gasket 7 between the bonnet 4 and the cylinder part 21 from both of the surfaces. Sealing effect due to the elasticity of the gasket is provided, and an opening/closing valve for high pressure gas of extremely high airtightness can thus be provided.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an on-off valve for high pressure gas such as a container valve.

[0002]

2. Description of the Related Art FIG. 6 is a sectional view showing a conventional container valve 1. The container valve 1 is attached to the opening of the high-pressure gas container G, and the cylinder valve 21 is formed on the upper side of the container valve body 2. A kelep 3 is provided in the cylinder portion 21 by screwing. When the kelep 3 is moved up and down,
The first gas passage 22 communicating with the container G and the second gas passage 23 connected to an external pipe (not shown) are opened and closed.

A bonnet 4 is screwed onto the upper end of the cylinder portion 21 so as to cover it from the outside, and a through hole 41 communicating with the inside of the cylinder portion 21 is provided at the center of the bonnet 4 in the length of the cylinder portion 21. It is formed in the vertical direction. The bonnet 4 is configured to be closely fitted to the upper end surface 20 and the outer peripheral surface of the pipe wall of the cylinder portion 21, and the inside of the joint surface 51 that is joined to the upper end surface 20 of the pipe wall has the above-mentioned penetration. The recess 5 is formed so as to surround the hole 41, and the outer edge (inner edge of the joint surface 51) of the recess 5 is the upper end surface 2 of the pipe wall.
It is located almost in the center of 0.

In the through hole 41 of the bonnet 4, a spindle 6 having a handle 60 engaged at its upper part is airtightly fitted so as to project into the cylinder portion 21, and the lower end portion of the spindle 6 is The kerep 3 is rotated so that the kerep 3 can be moved up and down relative to the kerep 3.
Is engaged with the upper end of the. For example, an engaging hole having a quadrangular cross section is formed on the side of the kelep 3, and the lower end portion of the spindle 6 is formed in a shape that fits the engaging hole.

In the recess 5 of the bonnet 4, there is provided a ring-shaped gasket 7 having a thickness slightly larger than the depth of the recess 5 as shown in FIG. 7 and having a mortar-shaped tapered portion 71 formed therein. The spindle 6 is tightly fitted onto the spindle 6. For example, the depth of the recess 5 is set to 1.8 mm, and the thickness of the gasket 7 is set to 2.0 mm. On the other hand, a flange portion 61 is formed on the spindle 6, but a spring 62 installed between the handle 60 and the spindle 6 is used.
Since the spindle 6 is always urged upward by the flange portion 61,
It is pressed to the side. Reference numeral 63 is a screw for adjusting the elastic force of the spring 62.

In the container valve 1 having such a structure, the handle 60 is operated to rotate the spindle 6 to move the kelep 3 up and down in the cylinder portion 21 while the opening and closing operations are performed. . Then, when the container valve 1 is opened, the gas in the container G is discharged from the kelep 3 and the cylinder portion 21.
Through the gap between the inner wall of the cylinder portion 21 and the inner wall of the cylinder portion 21, and fills the upper end of the cylinder portion 21. In this case, attach the bonnet 4 to the cylinder portion 21.
By strongly tightening it, the joint surface 51 of the bonnet 4 and the upper end surface 20 of the tube wall of the cylinder portion 21 are pressed against each other to keep airtightness in this portion.

[0007]

In the above-mentioned container valve, the gasket 7 is interposed between the bonnet 4 and the cylinder portion 21, and the joint surface 51 of the bonnet 4 and the upper end surface 20 of the pipe wall of the cylinder portion 21. And are pressure-contacted with each other, and the airtightness is maintained by the pressure-contact between the metal surfaces.
It is said that there is no risk of gas leakage even under high pressure of about kg / cm ² · G.

However, when the used container valve is reconditioned, the smoothness of the metal surface may be impaired and the hermeticity at the contact interface of the metal surface may be slightly reduced. On the other hand, the gas filling the upper end of the cylinder portion 21 passes through between the bonnet 4 and the cylinder portion 21 and the gasket 7 and reaches the inside of the contact interface. Therefore, if the contact interface has low airtightness, There was a problem that gas might leak through.

[0009]

According to the present invention, the joint surfaces of the outer peripheral portions of the first cylinder portion and the second cylinder portion are axially pressed against each other so as to be airtightly joined together, and the first cylinder portion is also provided. An on-off valve for high-pressure gas having a structure in which a shaft portion extends from the first cylinder portion to the second cylinder portion, at least one inner side of the joint surfaces of the first cylinder portion and the second cylinder portion. A recess is formed over the entire circumference so as to surround the shaft, and a ring-shaped gasket having a height greater than the depth of the recess is disposed in the recess, and the gasket is provided in the first The outer edge portion of the gasket is extended outward by pinching from both sides by the cylinder portion and the second cylinder portion so that the gasket is sandwiched between the joint surfaces of the first cylinder portion and the second cylinder portion. It is characterized in that .

[0010]

A recess is formed in at least one of the joint surfaces of the first cylinder part made of, for example, the bonnet and the second cylinder part made of, for example, the cylinder part of the container body, and the depth of the recess is greater than the depth of the recess. Provide a gasket with a large height. Then, by sandwiching the gasket from both sides by the first cylinder portion and the second cylinder portion, the outer edge portion of the gasket is extended and interposed between the first cylinder portion and the second cylinder portion. Therefore, since the metal surfaces do not contact each other at the joint surface between the first cylinder portion and the second cylinder portion, high airtightness can be maintained.

[0011]

EXAMPLES Next, examples of the present invention will be described. The container valve 1 of the present embodiment has the features described above with reference to FIG. 6 except that the bonnet 4 is joined to the upper end surface 20 of the pipe wall of the container valve body 2 (the pipe wall of the cylinder portion 21) and the gasket 7. It has the same structure as the conventional container valve 1 shown in FIG.

The main part of this embodiment will be described in detail below with reference to an enlarged view of the main part shown in FIG. That is, as described in FIG. 6 of the conventional example, the bonnet 4 is configured to be closely fitted to the upper end surface 20 and the outer peripheral surface of the pipe wall of the cylinder portion 21, and is joined to the upper end surface 20 of the pipe wall. A concave portion 5 is formed on the inner side of the joint surface 51 so as to surround the through hole 41, and an outer edge of the concave portion 5 (an inner edge of the joint surface 51) is substantially at the center of the upper end surface 20 of the pipe wall. Is located in.

The dimensions of each part will be described. The cylinder part 21 has an inner diameter A of 19 mm and the spindle 6 has a shaft diameter B of 12 mm. The recess 5 provided in the bonnet 4 has an outer diameter C of 22 mm and a deep depth. The thickness D is formed to be 1.8 mm.

As shown in FIG. 2, a ring-shaped gasket 7 made of, for example, Teflon and having a flat surface on both sides is externally fitted to the spindle 6 and the upper end surface of the cylinder portion 21 is fitted into the recess 5 of the bonnet 4. 20 and the joint surface 51 of the bonnet 4 are pressed into close contact with each other. The gasket 7 has a thickness E larger than the depth of the recess 5 and is formed to, for example, 2.5 mm. Since the thickness E of the gasket 7 is formed to be larger than the depth D of the recess 5 of the bonnet 4, when the gasket 7 is fitted into the recess 5, as shown in FIG. A gap is formed in the joint portion of the upper end surface 20 of the pipe wall of the portion 21. At this time, the spindle 6 is attached to the bonnet 4, and the flange portion 61 of the spindle 6 is pressed against the lower surface side of the gasket 7 by the spring 62.

When the bonnet 4 is fastened to the cylinder portion 21 with a torque wrench, for example, as shown in FIG. 3B, the gasket 7 has a recess 5 in the bonnet 4.
The bottom surface (the upper surface in FIG. 1) and the upper end surface 20 of the cylinder portion 21 are pressed from both sides with a pressing force corresponding to the torque of the torque wrench. At this time, gasket 7
Attempts to extend laterally, but the inner edge side of the gasket 7 cannot spread to the inner edge side because the spindle 6 exists. Therefore, as shown in FIG. 3 (c), the gasket 7 includes the joint surface 51 of the bonnet 4 and the cylinder portion 21.
It extends into the gap with the upper end surface 20 and is deformed into a thin film to be pinched by the joint surface 51 and the upper end surface 20.

The relationship between the above-described embodiment and the present invention will be described. The bonnet 4 and the cylinder portion 21 are the first, respectively.
Corresponding to the cylinder part and the second cylinder part of the joint surface 5
1 and the upper end surface 20 correspond to the joint surface of the outer peripheral portion of each cylinder portion, and the spindle 6 corresponds to the shaft portion.

According to this structure, the gasket 7 extends and intervenes between the joint surface 51 of the bonnet 4 and the upper end surface 20 of the tube wall of the cylinder portion 21. Since the sealing effect is obtained by the elasticity of, even if the smoothness of the metal surface is impaired due to the reconditioning of the used container valve 1, the airtightness is lowered by the contact between the metal surfaces like the conventional container valve. There is no fear and high airtightness can be maintained.

Whether the gasket 7 extends and is interposed between the joint surface 51 of the bonnet 4 and the upper end surface 20 of the cylinder portion 21 when the bonnet 4 is fastened to the cylinder portion 21 depends on the material and thickness of the gasket 7. It is considered that it is decided in relation to the shape. The conventional gasket 7 has a mortar-shaped taper portion 71 formed inside thereof and a thickness of 2 mm. The gasket 7 is formed into a recess of a depth of 1.8 mm formed in the bonnet 4. 5 and then press it with torque applied from both sides.
Tries to extend laterally as described above, but since the gasket 7 has the tapered portion 71, when the torque is applied, the compressed thickness escapes to the tapered portion 71. On the other hand, since the gasket 7 has almost no gap between the bonnet 4 and the cylinder portion 21 in the outer peripheral direction thereof, it can hardly be extended in this direction. Therefore, when the conventional gasket 7 is pressed from both sides, it only extends in the center direction and does not extend between the joint surface 51 of the bonnet 4 and the upper end surface 20 of the cylinder portion 21 which is effective for improving airtightness. .

An experiment conducted to determine the shape of the gasket 7 that effectively extends on the contact surface between the bonnet 4 and the cylinder portion 21 will be described. Ring inner diameter is 1
2mm, outer diameter is 22mm, thickness is 2mm, 2.5
mm and 3 mm, which are each formed of three types of Teflon, are closely fitted in the recess 5 formed in the bonnet 4 and are pressed with various torque values to increase the height of the container body 2 after pressing. Was measured. For comparison, the height of the container valve body 2 without the gasket 7 was also measured.

In this method, the container body 2 after pressing
If the height of the gasket 7 changes, it means that the shape of the gasket 7 has changed, and by comparing with the height of the container main body 2 without the gasket 7, the gasket at the contact portion between the bonnet 4 and the cylinder portion 21 is changed. It is determined whether or not 7 is extended and interposed.

Further, the upper end surface 20 of the cylinder portion 21 is labeled with a magic mark, and this magic mark is used for the joining surface 5 of the bonnet 4.
1000kg · c by checking whether or not to move to 1.
The presence or absence of metal contact in the contact portion between the bonnet 4 and the cylinder portion 21 when a torque of m or more was applied was examined.
The results are shown in Tables 1, 2 and 3, respectively.

[0022]

[Table 1]

[0023]

[Table 2]

[0024]

[Table 3] As can be seen from Table 1, when the gasket 7 having a thickness of 2 mm is used, the height of the container body 2 is the same as when the gasket 7 is not adhered, regardless of the torque value. As a result, it is recognized that the gasket 7 does not exist between the joint surface 51 of the bonnet 4 and the upper end surface 20 of the cylinder portion 21, and metal contact occurs at the contact portion between the bonnet 4 and the cylinder portion 21. , This means torque value 1000kg
・ In the case of cm or more, it was confirmed by the experiment with or without metal contact.

Further, from Table 2, it was confirmed that the height of the container body 2 gradually decreased as the torque value increased, and the height of the container body 2 was lowered by pressing the gasket having a thickness of 2.5 mm. Was done. And the torque value is 1000kg
・ The height of the container body is constant when it is more than cm. Therefore, in this test, when the torque is larger than about 1000 kg · cm, the height of the container body does not change even if the torque is increased. The height of the container body is 0.1 mm (110.5
0-110.40) Since it is large, the joint surface 5
It is supported that a part of the gasket 7 is interposed between 1 and the upper end surface 21. And again from Table 3, thickness 3m
For the gasket 7 of m, the same result as that of the gasket of thickness 2.5 mm is obtained, and a part of the gasket is extended and interposed between the bonnet 4 and the cylinder portion 21 by pressing from both sides of the gasket. Was recognized.

In the experiments shown in Tables 2 and 3, the gasket 7 was removed from the container valve and observed. When the torque value is 800 kg · cm or less, the gasket 7 is
Although no remarkable extension was observed from the outer edge of the gasket 7, extension from the outer edge of the gasket 7 could be confirmed when the torque value was 1000 kg · cm or more. The torque value may be set appropriately, but for example, about 1200 kg · cm is desirable.

As can be seen from the above experimental results, when the Teflon gasket 7 is used, in the container valve of the above example, if the thickness of the gasket 7 is about 2.5 mm or more, the gasket 7 is placed between the bonnet 4 and the cylinder portion 21. Although it is possible to obtain a structure in which a portion of the gasket 7 is extended and sandwiched, if the thickness of the gasket 7 is about 2.0 mm as in the conventional case, such a structure will not be obtained even if there is no taper portion on the inner edge side of the gasket 7. . Note that a taper may be provided on the inner edge side as long as a structure can be obtained in which the gasket 7 is interposed between the bonnet 4 and the cylinder portion 21 in relation to the material and the thickness.

Next, another embodiment of the present invention will be described with reference to enlarged sectional views around the gasket shown in FIGS. As shown in the figure, a thin film collar 72 is formed in advance on the outer peripheral portion of the gasket 7 of this embodiment.
The collar portion 72 is configured to be interposed between the bonnet 4 and the cylinder portion 21. The collar portion 72 is formed in conformity with the shape of the contact portion between the bonnet 4 and the cylinder portion 21, and is formed, for example, on the lower surface side of the gasket 7 as shown in FIG. 4 or on the central portion of the gasket 7 as shown in FIG. Can be formed. The container valve thus configured also has the same effect as that of the first embodiment described above.

The present invention can be applied not only to the container valve but also to a flow rate adjusting valve, a pressure reducing valve and the like.

[0030]

According to the present invention, since the outer edge portion of the gasket is extended and interposed between the joint surfaces of the first cylinder portion and the second cylinder portion, the seal due to the elasticity of the gasket is used.
It is possible to provide an on-off valve for high-pressure gas having a very high airtightness.

[Brief description of drawings]

FIG. 1 is an enlarged view showing a main part of a container valve according to an embodiment of the present invention.

FIG. 2 is a perspective view of a gasket according to an embodiment of the present invention.

FIG. 3 is an explanatory diagram for explaining the operation of the present invention.

FIG. 4 is an enlarged view showing a main part of another embodiment of the container valve according to the present invention.

FIG. 5 is an enlarged view showing a main part of another embodiment of the container valve according to the present invention.

FIG. 6 is a cross-sectional view showing a conventional container valve.

FIG. 7 is a cross-sectional view showing a conventional gasket.

[Simple explanation of symbols]

 1 Container Valve 2 Container Valve Main Body 21 Cylinder 3 Kerep 4 Bonnet 5 Recess 6 Spindle 7 Gasket

Claims (1)

[Claims] 1. A first cylinder portion and a second cylinder portion are joined together while air-tightly joining them by axially pressing the joining surfaces of the outer peripheral portions of the first cylinder portion and the second cylinder portion. An on-off valve for high-pressure gas having a structure in which a shaft portion is penetrated, the shaft portion is surrounded on an inner side of at least one of joint surfaces of the first cylinder portion and the second cylinder portion. A recess is formed over the entire circumference, and a ring-shaped gasket having a height larger than the depth of the recess is disposed in the recess, and the gasket is provided in each of the first cylinder portion and the second cylinder portion. The outer edge portion of the gasket is extended outwardly by being pinched from both sides by the so as to be sandwiched between the joint surfaces of the first cylinder portion and the second cylinder portion. Open / close valve for high pressure gas.