JPH07151282A - Coupling for connecting resin tube - Google Patents

Abstract

PURPOSE:To sufficiently develop the function of an insertion member and permit the insertion of a tube having a small diameter in a reasonable manner by forming a large diameter part which is nearly equal or slightly larger than the inside diameter of a tube, at a part of the outer periphery of an insertion part corresponding to the hook wall part on the holding member side of the insertion member. CONSTITUTION:When an insertion member 3 is inserted inside the top end of a tube T or the top end of the tube T is externally fitted with the insertion member 3 which is inserted in a coupling body 1, the deflection deformation to the tube T side in the vicinity of the biting-in part of the hook wall part of a holding contact member 2 is effectively prevented by the insertion in a local contact state to the inner peripheral surface of the tube T side by a large diameter part 3' which is nearly equal or slightly larger than the nominal dimension of the inside diameter of the tube T of the insertion member 3. Accordingly, the holding force of the holding member 2 is sufficiently developed, and the trouble of the generation of leak even under an oscillation state is prevented. Further, even in the case of a tube having a small diameter, the insertion into the insertion member 3 in a reasonable manner is enabled by spreading the diameter on the tube side, accompanied with the local contact with the large diameter part 3'.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention generally relates to a vehicle or various machines and devices under vibration, and is provided with a relatively small thickness of about 20 m / m or less, which is provided as a supply passage for oil supply, air supply, etc. The present invention relates to a joint for connecting a resin tube made of nylon or polyurethane having a diameter, and particularly to an insert member inserted inside the tip of the tube.

[0002]

2. Description of the Related Art Conventionally, in the case of this type of connecting joint, as shown in FIG. 6, the connecting state is inserted into a tube (T ') incorporated in the shaft core hole of the joint body (11). The fitting part is simply a cylinder (13 ') having the same diameter, and is inserted into the tube by an insert member (13), and an elastic holding member (12) hung on the rear peripheral end of the joint body is used to form the claw wall part. Was pressed against the outer peripheral surface of the tube (T ′) in a biting manner to establish a connection.

[0003]

However, it is usually desired that the outer diameter of the insert member be substantially the same as the inner diameter of the tube. However, since the inner diameter of the tube generally varies in dimensional accuracy. In consideration of the minimum inner diameter on the tube side, the outer diameter of the insertion portion on the insert member side is slightly smaller than the nominal size of the inner diameter of the tube, and is loosely fitted. Therefore, in the insert member (13) in the prior art in which the insertion portion is simply a cylinder (13 ') of the same diameter over the entire length, the tube (T ') Side, there is a tendency for inward bending deformation (14) to occur due to biting, and the holding force at the holding part decreases and the connection becomes unstable, and it is under vibrating conditions. It often had the problem of causing leaks.

Further, in the case of a tube having a small diameter, the entire outer peripheral surface of the insert member comes into contact with the tube, so that a high frictional force is generated and it is necessary to forcefully insert the tube.

The present invention has been made in view of the above problems of the prior art, and effectively prevents flexural deformation toward the tube side near the biting portion of the claw wall portion formed by the holding member in the connected state. However, the holding force of the holding part is fully exerted to ensure a reliable connection, the function of an insert member is not lost by eliminating the fear of leakage even under a vibrating condition, and a tube with a small diameter is used. Even if it exists, it is an object of the present invention to propose a joint for resin tube connection that can be reasonably inserted by the extension of the tube side due to local contact at a corresponding large diameter portion.

[0006]

In order to achieve the above object, the present invention provides a tubular insert member inside the distal end of a tube to be connected in a diameter-expanding chamber penetrating inside a shaft core hole of a joint body. In the joint for connection formed by inserting and attaching the elastic holding member having a biting claw wall on the outer peripheral surface of the tube, and corresponding to the claw wall portion of the holding member side formed by the insert member. The resin tube connecting joint is configured to have a large diameter portion, which is approximately equal to or slightly larger than the nominal dimension of the tube inner diameter, on a part of the outer periphery of the insertion portion to be inserted. A member is inserted and attached to the tube side or the joint body side prior to connection.

[0007]

Since the present invention is configured in this way, when the insert member is inserted into the tip of the tube in advance, or the tube end is externally fitted to the insert member previously inserted into the joint body, By inserting the large diameter portion of the insert member into the inner peripheral surface of the tube side in a locally abutting state, it is possible to effectively bend and deform the claw wall portion of the holding member toward the tube side near the biting portion. It is possible to prevent this, and the holding force of the holding part is fully exerted to ensure a reliable connection, and there is no fear of leakage even under vibrating conditions, etc., and the function as an insert member is sufficient. ,
Further, even a tube having a small diameter can be reasonably inserted into the insert member due to the expansion of the diameter of the tube due to the local contact with the large diameter portion.

[0008]

Embodiments of the present invention will now be described with reference to the drawings. FIG. 1 is a longitudinal sectional view of a joint for resin tube connection according to the present invention, which is cut in half in a connected state, and FIG. 2 is an insert member of FIG. 5 is a plan view of the whole insert member of FIG. 3, and FIG. 3 is a plan view of the insert member of FIG.
1 is another view equivalent to FIG. 1, in which (1) is a joint body, and nylon, polyurethane, cross-linked polyethylene, fluorine which is connected in the diameter expansion chamber (1 ') penetrating inside the shaft core hole is connected. A resin tube (T) made of resin or the like, an insert member (3) inserted inside the tip, and a tubular elastic holding member (2) having a claw wall on the tip side that bites into the outer peripheral surface of the tube It will be. Then, either hold the holding member (2) with the resin tube (T) inserted in it on the rear peripheral end of the expansion chamber (1 ') (Fig. 1) or screw it onto the joint body (1). It is connected either by engaging with the matching tightening nut (4) (Fig. 3).

The insert member (3) is particularly a holding member formed by the insert member in the inserted state.
(2) on a part of the outer circumference of the insertion part corresponding to the claw wall part,
The tube (T) to be connected has a large diameter part (3 ') that is approximately the same as or slightly larger than the nominal size of the inner diameter, and the large diameter part is the tube.
It is inserted in a state of locally abutting on the inner peripheral surface on the (T) side and the bite portion is formed by the claw wall. Reference numeral (3 ") is a flange-shaped stopper wall provided near the end of the insert member (3).

According to the present invention, the holding member (2) is not only formed in the above-described embodiment but also formed in a circular or cross-sectional shape as shown in FIG. It can also be applied to a resin tube connection joint in which the unlocking means (6) is laid on the inner peripheral surface of the sleeve (5) by making contact with the taper surface (5 ') of the suspended sleeve (5). 1 and FIG. 5, the elastic seal ring 7 intervenes to further improve the sealing performance.

[0011]

As described above, the joint for resin tube connection according to the present invention has a part of the outer periphery of the insertion portion corresponding to the claw wall portion of the holding member (2) formed by the insert member (3). Since it has the large-diameter portion (3 '), the holding member (2) in the connected state is inserted by locally abutting the inner diameter of the tube (T) side by the large-diameter portion. It is possible to effectively prevent bending deformation of the claw wall of the claw wall to the side of the tube near the biting part, sufficiently exert the holding force of the holding part, and securely connect it to the tube side. It does not function as an insert member (3) by eliminating the fear of leakage from the tube, and even if it is a tube with a small diameter, the corresponding large diameter portion (3 ') causes local contact with the tube. It is a very useful joint for resin tube connection that can be installed comfortably by stretching.

[Brief description of drawings]

FIG. 1 is a vertical cross-sectional view of a joint for resin tube connection according to the present invention, which is cut in half in a connected state.

2 is a plan view of the entire insert member of FIG. 1. FIG.

FIG. 3 is a view corresponding to FIG. 1 of the same as another embodiment.

FIG. 4 is a plan view of the entire insert member of FIG.

FIG. 5 is a view corresponding to FIG. 1 of still another embodiment.

FIG. 6 is a vertical cross-sectional view of a conventional example in which a joint for resin tube connection is half-cut in a connected state.

[Explanation of symbols]

 2 Holding member 3 Insert member 3'Large diameter part T tube

Claims (2)

[Claims] 1. A cylindrical insert member is inserted into the inside of the distal end of a tube to be connected in a diameter-expanding chamber penetrating inside the shaft core hole of a joint body, and bites into the outer peripheral surface of the tube. In the joint for connection, which is configured by internally holding and holding an elastic holding member having a claw wall, the insert member
A part of the outer periphery of the insertion part corresponding to the holding member (2) side claw wall formed by (3) has a large diameter part (3) that is approximately equal to or slightly larger than the nominal size of the inner diameter of the tube (T). A joint for resin tube connection, characterized in that 2. The resin tube connection according to claim 1, wherein the insert member (3) is inserted and attached to the tube (T) side or the joint body (1) side prior to connection. Fittings.