JP2000046272A - Joint for soft pipe - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent connecting failure of a soft pipe by enlarging a visual piece and projecting it from a window hole when a length for inserting the soft pipe into a pipe inserting part is not less than a predetermined rate, and engaging a stopper with cutout formed on a box nut by restoring force of the visual piece when the length is less than the predetermined rate. SOLUTION: In a condition in which the degree for inserting a soft pipe P into a pipe inserting part 1b is shallow, a stopper 2b is engaged with a cutout 4a of a box nut 4 screwed around a male screw part 1c, and rotation of the box nut 4 is restricted. In the case where the soft pipe P is pushed and inserted to the most end of the pipe inserting part 1b, a ring part 2a of an indicator 2 is pushed to a pipe end of the soft pipe P, the stopper 2b is moved to a flange 1a along a guide groove 1d, a visual piece 2c is more enlarged, and the visual piece 2 is exposed from a window hole 1e for a constant rate while sliding. A worker visually confirms the exposed visual piece 2c from the window hole 1e. It is thus possible to beforehand prevent connecting failure.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a joint for a soft tube, and more particularly, to a structure capable of preventing a poor connection of a soft tube.

[0002]

2. Description of the Related Art Conventionally, as a joint for a soft tube, as shown in FIG. 6, a tube insertion portion (b) is provided on a body (a) of a joint main body and a male screw portion (d) provided coaxially outside the tube insertion portion. ) And insert a soft tube (c), and insert this soft tube (c) into the male thread (d)
Chuck ring (F) with cap nut (E) screwed into
There has been widely known a structure in which the tube is fastened to a tube insertion portion (b) through a hole.

In the above conventional pipe joint, the insertion depth of the soft pipe (c) into the pipe insertion portion (b) is entirely dependent on the pipe of the operator, so that the insertion depth L is not constant. When the insertion length L is shorter than the predetermined amount, the cap nut (e) is frequently tightened, which causes a leak of the soft pipe (e) due to poor connection of the soft pipe (e), and the like. Things.

In order to solve the above-mentioned inconveniences, a connection pipe insertion confirmation hole is opened at the back end of the male thread portion of the joint body, and the inside pipe end position can be directly checked through this confirmation hole to confirm. Alternatively, a pin is inserted into a pin hole formed in the enlarged diameter portion of the joint main body, and an annular bulge contacting the lower end of the pin is formed at the tip of the connection pipe. However, there has been known a technical means for confirming the insertion amount of a tube by exposing a pin pushed up to the above-mentioned bulging portion when the tube has been inserted for a predetermined length from a pin hole (for example, Japanese Utility Model Application Laid-Open No. HEI 1-1990). No. 133593).

[0005]

However, in the former, that is, the pipe joint disclosed in Japanese Patent Application Laid-Open No. 2-163592, it is not easy to confirm the inner pipe end through the window in a narrow and dark field environment. Its accuracy was difficult to achieve, and in the latter case, that is, in the connector for connecting a small-diameter pipe described in Japanese Utility Model Application Laid-Open No. 1-133593, the set position and shape of the annular bulge formed near the tip of the connection pipe were highly accurate. It is the greatest requirement to finish it, and the processing can not be done on site at any time.In addition, if the joint body is not installed so that the pin hole is located at least in the upper half of the joint body, the pin will not be There is a risk that the pin may fall off, and in order to overcome this, there has been a problem that the complicated structure of the engagement between the pin and the pin hole is unavoidable.

SUMMARY OF THE INVENTION The present invention has been made based on the above-mentioned problems, and an object of the present invention is to make it easier to visually recognize the insertion condition of a soft tube than in the prior art, and to reduce the insertion length of the soft tube. If not enough, it is an object of the present invention to provide a joint structure that can more reliably prevent poor connection of a soft tube by restricting rotation of a cap nut.

[0007]

First, the present invention is applied to a method in which a soft tube inserted into a tube insertion portion of a joint body is screwed with a cap nut on a male screw portion provided coaxially on the outer periphery of the tube insertion portion. This is a soft tube joint that is tightened via a chuck ring by joining. Then, as a means for achieving the above object, a stopper is raised in a radial direction from a ring portion which is inserted into the tube insertion portion of the joint main body and can contact the tube end of the soft tube. This stopper engages with a notch formed in the cap nut, as described later, to restrict rotation of the cap nut. Further, at least one pair of flexible visual pieces that expand in the axial direction from the ring portion is provided, and the ring portion, the stopper, and the visual piece constitute an indicator. In correspondence with the indicator, the male screw portion of the joint main body is provided with a window hole through which the visual piece can be inserted, and a guide groove that allows the stopper to move in the axial direction. When the insertion length with respect to the insertion portion is equal to or more than a predetermined amount, the visual piece is further expanded to protrude from the window hole, and when the insertion length is equal to or less than a predetermined amount, the stopper is moved by the restoring force of the visual piece. A configuration was adopted in which a notch formed in the cap nut could be engaged.

According to the second aspect of the present invention, in the above structure, the joint main body has a flange continuous with the male screw portion on the back end side, a guide groove is provided up to the flange, and the insertion length of the soft tube is longer than a predetermined amount. At some point, a means was adopted for the escape portion of the stopper.

[0009]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The configuration and operation of the present invention will be clarified below based on the preferred embodiment shown in FIGS. First, as shown in the exploded perspective view of FIG. 1, the soft tube joint according to this embodiment is roughly divided into four members: a joint main body 1, an indicator 2, a chuck ring 3, and a cap nut 4. The feature of the present invention resides in adopting the structure 2 and the structure corresponding thereto.
The connection of the soft tube P is the same as that of a conventional joint in that the soft tube P is fastened and fixed to the joint body 1 via the chuck ring 3 by the cap nut 4. That is, as shown in FIG. 2, the fitting body 1 has a flange 1a formed in the body portion as a rear end, and a tube insertion portion 1b communicating with the soft tube P to form a fluid passage.
And a male screw portion 1c for screwing the cap nut 4 around the outer periphery thereof. The soft tube P is inserted into the tube insertion portion 1b via the cap nut 4, and then the cap nut 4 is screwed into the male screw portion 1c. As a result, the tapered inner surface of the cap nut 4 acts on the tapered outer surface of the chuck ring 3, and the soft pipe P is tightened and fixed to the pipe insertion portion 1 b by the diameter reducing action of the chuck ring 3 accompanying the tightening of the cap nut 4. It is something to do.

In this configuration, as shown in FIGS. 1 and 3, the indicator 2 is provided with a ring 2a having a diameter insertable into the pipe insertion portion 1b of the joint body 1 and a predetermined length in the radial direction from the outer periphery thereof. The stopper 2b is provided upright, and a pair of visual pieces 2c, 2c are further provided in a hakama shape from the ring portion 2a in the axial direction. In the present embodiment, the visual indicators 2c are made flexible by molding the entire indicator from plastic.

In response to this, the joint body 1 is provided with a guide groove 1d in which the stopper 2b of the indicator 2 is movable from the male screw portion 1c to the flange 1a, as is apparent from FIG. Further, window holes 1e, 1e through which the visual pieces 2c, 2c of the indicator 2 can protrude are opened at the far end of the male screw portion 1c. In addition, a notch 4 a capable of engaging with the stopper 2 b of the indicator 2 is provided at an opening end of the cap nut 4 on the joint body 1 side.

However, the indicator 2 uses an appropriate jig to insert the ring portion 2a into the pipe insertion portion 1b of the joint body 1 and to align the stopper 2b along the guide groove 1d of the joint body 1 with the visual piece 2c. 2c is fitted into the window holes 1e and 1e, and set in the joint body 1 in advance (see FIG. 2).

The indicator 2 thus set
As shown in FIG. 4, before connecting the soft tube P, the stopper 2b is positioned in the middle of the male screw portion 1c of the joint body 1 due to the restoring force of the visual pieces 2c and 2c themselves. Therefore, in this state, or in a state where the degree of insertion of the soft tube P into the tube insertion portion 1b is shallow, the stopper 2b is trying to screw into the male screw portion 1c.
And the rotation of the cap nut 4 is regulated, so that the poor connection of the soft tube P is prevented beforehand.

Next, when the soft tube P is pushed deep into the tube insertion portion 1b, the ring portion 2a of the indicator 2 is pushed by the tube end of the soft tube P as shown in FIG. As a result, the stopper 2b moves along the guide groove 1d to the flange 1a, and the visual pieces 2c, 2c further expand and slide out to be exposed from the window holes 1e, 1e by a certain amount. Then, the operator can confirm that the soft tube P has been inserted into the tube insertion portion 1b to a position suitable for connection by visually checking the visual pieces 2c and 2c exposed from the window holes 1e and 1e. At this time, the stopper 2b moves to the flange 1a.
Since the cap nut 4 is not engaged, the screwing operation of the cap nut 4 can be performed with an optimum insertion state. In other words, of the guide grooves 1d formed in the male screw portion 1c of the joint body 1,
A portion corresponding to the flange 1a can be referred to as a relief portion of the stopper 2b. In the present embodiment, the stopper 2b
Is formed in an L-shape such that the tip side is closer to the flange, the escape of the stopper 2b can be ensured, and the cap nut 4 can be tightened to a position where it comes into contact with the flange 1a. Further, in the present embodiment, the pair of visual pieces 2c, 2c are provided at the opposing positions. Therefore, even if one of them cannot be visually recognized depending on the viewing angle, the other can always be visually recognized. Confirmation is certain.

In the above-described embodiment, the visual strip 2c is used.
Is set to two, but the object of the present invention is achieved even if the number is three or more. In addition, it is possible to ensure the visibility by attaching a mark such as a color or a line to the visual piece 2c, and when a plurality of marks are provided according to the degree of insertion of the soft tube P, fine marks are provided. Confirmation work becomes possible.

[0016]

As described above, according to the joint for a soft tube according to the present invention, when the insertion of the soft tube is shallow, the rotation of the cap nut is restricted by the stopper, thereby preventing the connection failure. Can be. At the same time, the insertion length of the soft tube can be confirmed based on the amount of exposure of the visual piece, and the visual piece can be visually recognized from any angle, so that poor connection of the soft tube can be more reliably prevented. In addition, in the invention according to claim 2, since the escape portion of the stopper is provided, the screwing operation of the cap nut in the optimum insertion state is reliable.

[Brief description of the drawings]

FIG. 1 is an exploded perspective view of a soft tube and a joint.

FIG. 2 is a half sectional side view of a joint when a soft tube is inserted.

FIG. 3 is a front view (A) and a cross-sectional view (B) of the indicator.

FIG. 4 is a perspective view of a joint before insertion of a soft tube.

FIG. 5 is a perspective view of a joint when a soft tube is inserted.

FIG. 6 is a half sectional side view showing a conventional soft tube joint.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Joint main body 1a Flange 1b Pipe insertion part 1c Male thread part 1d Guide groove 1e Window hole 2 Indicator 2a Ring part 2b Stopper 2c Visual strip 3 Chuck ring 4 Cap nut 4a Notch P Soft tube

Claims (2)

[Claims] 1. A soft tube inserted into a tube insertion portion of a joint body,
In a joint of a soft tube in which a cap nut is screwed into a male screw portion provided coaxially on the outer periphery of the tube insertion portion to tighten the tube via a chuck ring, the soft tube tube is inserted into the tube insertion portion, and The joint main body includes an indicator which is provided with at least one pair of flexible visual pieces which are provided in a radial direction from a ring portion capable of coming into contact with an end and which expand in the axial direction from the ring portion. The male screw portion is provided with a window hole through which the visual piece can be inserted, and a guide groove that allows the stopper to move in the axial direction, and the insertion length of the soft tube into the tube insertion portion is a predetermined amount or more. Sometimes, while the visual piece is further expanded and projected from the window hole, when the insertion length is less than a predetermined amount, the stopper can be engaged with the notch formed in the cap nut by the restoring force of the visual piece. Joint soft tube, characterized in that it has. 2. The joint body has a flange connected to the male screw portion on the back end side, a guide groove extending to the flange, and a relief portion of the stopper when the insertion length of the soft tube is a predetermined amount or more. The joint for a soft pipe according to claim 1, wherein