JP3358968B2 - Fitting for container valve - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method of rotating a cap nut screwed into a thread portion of one piece on a container valve side to press a sealing face of the other piece against a sealing face of one piece via a gasket. The present invention relates to a joint for a container valve for sealingly connecting both pieces.

[0002]

2. Description of the Related Art For example, in the semiconductor industry such as ICs and LSIs, work is performed in a clean room from which fine particles and the like are eliminated, and the environment and conditions for manufacturing work are becoming even more severe. The special gas used in this manufacturing operation is introduced into the room from outside the clean room through a pipe or the like. However, it is extremely disliked that other unnecessary gas molecules such as air are mixed into the special gas.

[0003] For this reason, there has been a demand for ultra-precision joints for connecting pipes and valves (such as container valves) as well as pipes. Further, in the case of a joint for a container valve applied to a high-pressure gas container or the like, complete sealing is required from the viewpoint of security and the like.

Therefore, regarding such a joint for a container valve,
In Japan, JIS standards have been established,
Overseas, CGA standards (COMPRESSED GAS
ASSOCIATION) has been established.

FIGS. 7 and 8 show a conventional structure of a joint for a container valve manufactured according to the CGA standard. In these figures, 10 is one piece on the container valve side, 20 is the other piece (nipple), 30 is a gasket, and 40 is a cap nut.

On the other hand, a screw portion (male screw portion 11) is integrally formed on the outer peripheral surface of the piece 10,
A sealing surface 15 is formed on the inner surface thereof. On the other hand, the piece (nipple) 20 is hermetically attached to a connection pipe (not shown), and a seal surface 25 is formed at a tip end thereof.

The gasket 30 is made of, for example, metal, and has a sealing surface 15 of one piece 10 and another piece 20.
And the sealing surface 25.

[0008] The cap nut 40 is formed on its inner peripheral surface with a female screw part 41 which is rotatable by screwing with the screw part (11) of the one piece 10, and the other piece 20 is covered in the axial direction. A through hole 42 is formed to be fittable. On the inner surface of the cap nut 40, a pressing surface 46 capable of pressing the rear end surface 27 of the engaging flange 26 of the other piece 20 is formed.

Each of the pieces (10, 20) and the cap nut 40 are made of metal (for example, stainless steel or brass).

The cap nut 40 (female screw portion 41) of the other piece 20 is screwed into the male screw portion 11 of the one piece 10 and rotated in a predetermined direction so that the other piece 20 is pressed by the pressing surface 46 of the other piece 20. When pressed against 10, both sealing surfaces (15, 25) are pressed and closely attached to gasket 30. As a result, the two pieces (10, 20) are sealed and connected.

Here, in the above-mentioned container valve joint, when the cap nut member 40 is rotated to tighten the two pieces (10, 20) in the axial direction, the other piece 20 rotates following (co-rotation). As a result, a situation may occur in which the seal surface 25 rotates while being pressed against the seal surface 15 via the gasket 30.

When such a situation occurs, the sealing surface (1)
5, 25) and the abutment surface of the gasket 30 may be scratched and sealability may be impaired, and there is a risk that gas (toxic gas or the like) in the piping may leak. In addition, a metal sealing surface (1
5, 25) and the gasket 30 rub against each other to generate particles, which may flow into the pipe.

Conventionally, an engagement groove 13 is provided on the outer peripheral surface 12 on the distal end side of the one piece 10 so that the other piece 20 does not rotate together with the cap nut 40 when the cap nut 40 is rotated. Is integrally formed with a projection (key portion 23K) that engages with the engagement groove 13 and makes the two pieces (10, 20) relatively unrotatable.

Here, the engagement groove 13 on the one piece 10 side extends in the axial direction of the piece 10 and has a constant width dimension, and the end face on the back side has a semicircular arc shape. Further, the key portion 23K on the other piece 20 side extends in the axial direction of the piece 20 and has a constant width dimension and a semicircular arc shape at the tip end so that the key portion 23K on the other piece 20 can be fitted into the engagement groove 13 without play. I have.

[0015]

In the joint for a container valve described above, the key portion 23K integrally formed on the outer peripheral surface 22 of the other piece 20 is provided with the engaging groove 1 on the one piece 10 side.
It is necessary to perform precision processing so as to be inserted into the shaft 3 in the axial direction so as to prevent play in the rotation direction.

Accordingly, the outer peripheral surface 22 of the other piece 20
Is first machined with a lathe so as to have an outer diameter dimension including the key portion 23K, and then cut using an end mill at a machining center so that the outer diameter becomes a predetermined size except for the portion to be the key portion 23K. Thereafter, the chucking is changed, and the tip portion of the key portion 23K is processed into a semicircular shape, and the width is processed in accordance with the width of the engagement groove 13.

As described above, the outer peripheral surface 22 of the other piece 20
In order to integrally form the key portion 23K, a large number of processing steps are required and the cost is increased.

An object of the present invention is to provide a joint for a container valve which can reduce the number of processing steps and reduce the cost while preventing the other piece from rotating together when the cap nut is rotated.

[0019]

According to a first aspect of the present invention, a cap nut screwed into a threaded portion of one piece on a container valve side is rotated to seal a seal face of the other piece via a gasket. In a joint for a container valve, which seals the two pieces by pressing against the surface , an engagement concave portion is provided on the outer peripheral surface at the tip end of the one piece , and the outer peripheral surface of the other piece and the seal are provided.
A hole is formed at a position distant from the hole surface , and the hole can be attached to the hole and inserted into the engaging recess to prevent the other piece from rotating following the cap nut. An engaging projection shaft member having a circular cross section is provided.

In this invention, even if the cap nut is rotated to tighten the one and the other pieces in the axial direction, the other piece follows the engagement projection shaft member inserted into the engagement recess on the one piece side. Rotation (co-rotation) is prevented. For this reason, the sealing surfaces of the two pieces and the gasket do not rub against each other, causing scratches or particles.

Here, the engaging projection shaft member may be any as long as it can be attached to the hole of the other piece and is fitted into the engaging recess on the one piece side and does not rattle in the rotation direction. For example, if a screw hole is formed as a hole, a commercially available screw or the like can be used. Therefore, as compared with the conventional example in which the key portion is integrally formed on the outer peripheral surface of the other piece, the number of processing steps can be greatly reduced and cost can be reduced.

The invention according to claim 2 is a container valve joint in which a thrust bearing is interposed between the pressing surface of the cap nut and the other piece.

In this invention, when the cap nut is turned, the thrust bearing transmits the axial force (axial force) from the cap nut to the other piece, but transmits almost the rotational force (rotating power). do not do. Therefore, one and the other pieces can be tightened more strongly without rotating the other piece, and the seal connection can be made more reliably.

Further, since the turning power of the cap nut hardly acts on the engaging projection shaft member, there is no problem even if an inexpensive screw having a low structural strength is used. Therefore, the same operation and effect as those of the first aspect of the invention can be obtained, the cost can be further reduced, and the two pieces can be tightened with a stronger force to more securely seal-connect.

[0025]

Embodiments of the present invention will be described below with reference to the drawings. (First Embodiment) As shown in FIGS. 1 to 3, the basic structure of the present valve joint is the same as that of the conventional example (FIGS. 7 and 8). In addition to providing the concave portion (13), the other piece 20 is provided with an engaging projection shaft member (screw 23) that can be inserted into the engaging concave portion (13).
At the time of rotation of 0, the other piece 20 can be prevented from following and rotating.

Components common to those in the conventional example (FIGS. 7 and 8) are denoted by the same reference numerals, and description thereof will be simplified or omitted.

The one piece 10 on the container valve side is provided with an engagement recess (13). A hole (24) is formed in the other piece 20, and an engaging projection shaft member (23) is attached to the hole (24).

In this embodiment, a screw hole 24 as a perforated portion is formed on the outer peripheral surface of the engaging flange 26 of the other piece 20, and the screw hole 24 serves as an engaging projection shaft member. Screw 23 is screwed. The screw 23 uses a general commercial product.

The engagement recess is formed by an engagement groove 13 provided on the outer peripheral surface 12 on the tip end side of the one piece 10. The width and the like of the engagement groove 13 are selected so that the screw 23 can be fitted in the axial direction so as to be able to move in the axial direction and not to rotate in the rotational direction.

The gasket 30 is made of metal. The gasket 30 has an outer peripheral surface 2 of the other piece 20 via a retainer 35.
2 is held at the tip.

Next, the operation of this embodiment will be described. One piece 10 on the container valve side and connection piping (not shown)
In the case of sealing connection with the other piece 20 on the side, first, the two pieces (10, 20) are butted so that their axes coincide with each other, and in this state, the cap nut 40 is screwed into the threaded portion (11) on the one piece 10 side. And rotate in a predetermined direction.

At this time, the screw 23 fitted in the engagement groove 13 of the one piece 10 prevents the other piece 20 from following and rotating. Therefore, both pieces (10, 2
There is no occurrence of a situation in which the sealing surface (15, 25) of (0) rubs against the gasket 30 and is scratched or particles are generated.

Thus, when the cap nut 40 is rotated,
The engaging flange 26 of the other piece 20 is pressed toward the one piece 10 by the pressing surface 46 of the cap nut 40. As a result, the sealing surface 25 of the other piece 20 is
Is pressed against the sealing surface 15 of the one piece 10 via
As a result, the two pieces (10, 20) are sealed and connected.

According to the first embodiment,
One piece 10 is provided with an engaging recess (engaging groove 13), and the other piece 20 is formed with a hole (screw hole 24), and is attached to the hole (24) to engage with the engaging recess (13).
Into the other piece 20 when the cap nut 40 is rotated.
Is provided with an engagement projection shaft member (screw 23) that can prevent the following pieces from rotating, so that when the cap nut 40 is rotated, the other piece 20 is prevented from rotating together and the number of processing steps is reduced. Cost can be reduced.

Further, since a commercially available screw 23 is used as the engaging projection shaft member, the number of processing steps can be further reduced, and the cost can be further reduced. Also,
Exchange and the like can be performed more easily.

A pin (not shown) or the like may be used as the engaging projection shaft member. In this case, the other piece 1
At 0, a hole is formed as a perforated portion, into which a pin can be pressed.

(Second Embodiment) A second embodiment is shown in FIG.
6 to FIG. The container valve joint according to the second embodiment has a configuration in which a thrust bearing 50 is interposed between the pressing surface 46 of the cap nut 40 and the other piece 20. Thus, when the cap nut 40 rotates, the rotating force acting on the other piece 20 from the cap nut 40 is greatly reduced, and the co-rotation of the other piece 20 is more reliably prevented.

The same components as those in the first embodiment are denoted by the same reference numerals, and description thereof will be simplified or omitted.

The thrust bearing 50 is formed of a plurality of balls and a pair of annular plates, and is mounted in a concave portion 47 formed in the pressing surface 46 of the cap nut 40. That is, the thrust bearing 50 is provided between the pressing surface 46 of the cap nut 40 and the rear end surface 27 of the engagement flange 26 of the other piece 20.
Interposed between In FIG. 5, reference numeral 55 denotes a position regulating ring for regulating the position of the thrust bearing 50.

Here, when the cap nut 40 is rotated, the thrust bearing 50 transmits the axial force from the cap nut 40 to the other piece 20, but hardly transmits the rotating power. Therefore, the one and the other pieces (10, 20) can be further strongly tightened without rotating the other piece 20, and a more reliable seal connection can be achieved.

Since the turning power of the cap nut 40 hardly acts on the screw 23, there is no problem even if an inexpensive screw having a low structural strength is used.

Therefore, according to the second embodiment, the cost can be reduced while further preventing the other piece 20 from rotating together when the cap nut 40 is rotated.

In addition to the case where the cap nut 40 is rotated and the two pieces (10, 20) are tightened (when they are fully tightened), the engagement with the engaging recesses (13) is performed not only during the work before the full tightening. Since the relative rotation of the two sealing surfaces (15, 25) is prevented by cooperation with the projection shaft member (23), the gasket 30 rubs against the sealing surfaces (15, 25) and the sealing performance is impaired. Does not occur.

As described above, since the gasket 30 is reliably prevented from being scratched, the gasket 30 may be a soft gasket, such as a C-ring or Teflon / Diflon, in addition to the metal gasket. Further, the form of the sealing surfaces (15, 25) is not limited to a flat type having a flat shape, and may be any of a projection type in which a portion in contact with the gasket 30 becomes a ring-shaped convex portion or a concave type in which a ring-shaped concave portion is formed. May be.

[0045]

According to the first aspect of the present invention, an engagement recess is provided in one of the pieces on the container valve side, and the other piece is inserted into the hole in the hole of the other piece so as to follow the other piece. Since the engagement projection shaft member that can be prevented is provided, the number of processing steps can be reduced while preventing the other piece from rotating together when the cap nut is tightened and rotated.

According to the second aspect, in addition to the first aspect, a thrust bearing is interposed between the pressing surface of the cap nut and the other piece. In addition to the effect, the seal connection can be more reliably performed, and the cost can be further reduced.

[Brief description of the drawings]

FIG. 1 is a diagram for explaining a first embodiment of the present invention.

FIG. 2 is a view for explaining the internal structure of one piece, the other piece, and the cap nut.

FIG. 3 is a view for explaining one and the other pieces which are also sealed and connected via a gasket.

FIG. 4 is a diagram for explaining a second embodiment of the present invention.

FIG. 5 is a view for explaining the internal structure of one piece, the other piece, and the cap nut;

FIG. 6 is a view for explaining one and the other pieces which are also sealed and connected via a gasket.

FIG. 7 is a view for explaining a conventional configuration of a joint for a container valve.

FIG. 8 is a view for explaining one and the other pieces which are sealed and connected via a gasket.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 10 One piece 11 Male thread part (screw part) 12 Front end outer peripheral surface 13 Engagement groove (engagement concave part) 15 Seal surface 20 Other piece 22 Outer peripheral surface 23 Screw (engagement projection shaft member) 24 Screw hole (hole) Reference Signs List 25 sealing surface 26 engaging flange portion 27 rear end surface 30 gasket 35 retainer 40 cap nut 41 female screw portion 42 through hole portion 46 pressing surface 47 concave portion 50 thrust bearing 55 position regulating ring

Claims (2)

(57) [Claims] 1. A cap nut screwed into a threaded portion of one piece on a container valve side is rotated to press a sealing face of the other piece against a sealing face of one piece via a gasket, thereby sealingly connecting the two pieces. In the joint for a container valve, an engagement concave portion is provided on a tip outer peripheral surface of the one piece , and a perforated portion is formed on the outer peripheral surface of the other piece and at a position away from the sealing surface, and is attached to the perforated portion. A coupling member having a circular cross-section that can be inserted into the engagement recess and prevent the other piece from rotating following the rotation of the cap nut. . 2. The container valve joint according to claim 1, wherein a thrust bearing is interposed between the pressing surface of the cap nut and the other piece.