JP2003207084A - Pipe fitting - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a pipe fitting having an enhanced reliability on the tube inserting and connecting operations by preventing missing of a small sleeve to hold a tube connected with the pipe fitting. <P>SOLUTION: The body 2 of the pipe fitting 1 is furnished at its one end with an inner cylindrical part 5 and an outer cylinder part 6, between the two with a ring-shaped sleeve inserting groove 7, and with a tube fitting cylinder part 8 continued to the inside surface of the inner cylinder part 5, having a small wall thickness and furnished with an engaging pawl 10 on the peripheral surface. The sleeve 3 is fitted on the periphery of the tube 4 to be fitted to the cylinder part 8, slidable inside the groove 7, and when slided in the direction of Arrow A, it holds the tube in the slipoff prevented condition in which the tube 4 bites into the pawl 10. A stopper 3a at the end of the sleeve 3 is engaged with stoppers 6a protruding from the open side end of the groove 7 so that the sleeve 3 has no risk of slipping off and missing. If the sleeve 3 is formed from a transparent material, it is possible to ocularly check the inserted condition of the tube 4, and the reliance upon the works executed is enhanced. <P>COPYRIGHT: (C)2003,JPO

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a tube having a small diameter and a high flexibility for supplying and discharging a gas such as air to and from a fine speed cylinder, especially for supplying and discharging a small amount of gas. The present invention relates to a pipe joint suitable for connecting and using.

[0002]

2. Description of the Related Art Conventionally, as this type of pipe fitting, a tube is fitted to a tube fitting tubular portion having a locking claw portion in a fitting body, and a sleeve is fitted to the outer circumference of the tube to fit the tube. A configuration is known in which the engaging claw portion is bitten into and held in a retaining state.

[0003]

In the conventional structure as described above, the sleeve is fitted to the outer circumference of the tube to hold the tube in the retaining claw so as to prevent the tube from being pulled out. Strength and sealability can be improved. However, the tube fitting tubular portion in the fitting body, in which the tube and the sleeve are fitted, is thin and inferior in strength. Therefore, when a force is applied to the tube in the lateral direction from above, below, left or right, the tube fitting tubular portion may be broken at the base portion, resulting in poor vibration resistance and lateral tensile strength. Therefore, the applicant of the present application was previously published as Japanese Patent Laid-Open No. 2001-248776, and as shown in FIG. 4, a pipe joint 1 is composed of a joint body 2 and a sleeve 3, and the joint body 2 is an inner tubular portion 5. It has an outer tubular portion 6, an annular sleeve insertion groove 7 between the inner tubular portion 5 and the outer tubular portion 6, and a thin wall following the inner peripheral portion of the inner tubular portion 5. Locking claw 1 on the outer peripheral surface
0 has a tube fitting tubular portion 8 while the sleeve 3 is fitted to the outer peripheral portion of the tube 4 fitted to the tube fitting tubular portion 8 and has an end portion with a sleeve insertion groove 7 It is proposed that the tube 4 is fitted in the inner tubular portion 5 and the tube 4 is held in a retaining state so as to bite into the locking claw portion 10 of the tube fitting tubular portion 8.

According to the technique thus constructed, the sleeve can be fitted to the outer circumference of the tube and the tube can be held in a retaining state so as to bite into the locking claw portion.
Also, since the end of the sleeve is fitted to the inner tubular part that is thicker and has better strength than the tubular part for tube fitting, even if force is applied to the tube in the lateral direction, it will be attached to the base part of the tubular part for tube fitting. It is possible to prevent the strain force from being concentrated and prevent the breakage.

However, in such a pipe joint, since the sleeve is very small, there is a problem in that the sleeve is lost during the work of inserting or withdrawing the tube. Furthermore, since the sleeve is made of a metal material, it is opaque, and it is not possible to visually check whether the tube has been inserted to the specified size. I can not judge whether,
The certainty of the work remained a problem.

The present invention is intended to solve the problems of the conventional pipe joints as described above, and there is no concern that the sleeve will be lost during the operation, and the pipe joints can be surely inserted. It is intended to provide.

[0007]

According to the present invention, there is provided an inner sleeve portion and an outer sleeve portion on one end side, and an annular sleeve is provided between the both sleeve portions. A joint body including an insertion groove, a tube fitting tubular portion having an inner peripheral portion of the inner tubular portion and a thin wall and an engaging claw portion on an outer peripheral surface thereof, and the tube fitting tubular portion. The tube is fitted to the outer peripheral portion of the tube, and the end portion is slidably fitted to the inner tubular portion within the sleeve insertion groove, and the tube is fitted to the tube fitting tube. A sleeve that holds the tube in a retaining state such that the inner surface of the tube slides into the locking claw portion of the tubular portion for tube fitting after the sleeve is slid, and the sleeve is slid.
A stopper is projected at the outer cylindrical portion at the opening side end of the sleeve insertion groove of the joint body and at the end of the sleeve at the innermost side of the sleeve insertion groove to separate the joint body from the sleeve. This is solved by preventing the sleeve from falling off by engaging both stoppers when operating in the direction.

Further, according to the present invention, the above-mentioned problems can be solved by forming the sleeve from a transparent material or a semi-transparent material in the preceding paragraph.

[0009]

BEST MODE FOR CARRYING OUT THE INVENTION According to the present invention, a pipe joint, which is used by connecting a tube to supply and discharge gas to and from a device, uses a sleeve in addition to the joint body, and the sleeve does not separate from the joint body. It was done like this.

The joint body has an inner tubular portion and an outer tubular portion on one end side, and is provided with an annular sleeve insertion groove between the both tubular portions. Following the inner peripheral portion, a tube fitting tubular portion having a thin wall and an outer peripheral surface having locking claw portions is provided. On the other hand, the sleeve is fitted to the outer peripheral portion of the tube that is fitted to the outer peripheral portion of the fitting tubular portion, and the end portion is slidable to the inner tubular portion within the sleeve insertion groove. After being fitted, the tube is fitted into the tube fitting tubular portion, and then the sleeve is slid so that the inner surface of the tube bites into the locking claw portion of the tube fitting tubular portion to prevent the tube from coming off. Configure to hold the tube.

Then, stoppers are made to project respectively at the outer cylindrical portion at the opening side end of the sleeve insertion groove of the joint main body and at the end of the sleeve on the innermost side of the sleeve insertion groove, and the joint main body When the sleeve and the sleeve are operated in the separating direction, the stoppers are prevented from coming off by engaging both stoppers.

The sleeve is made of a transparent material or a translucent material. As a result, it is possible to visually confirm whether or not the inserted state of the tube has reached the predetermined size, and it is possible to determine whether or not the inserted state is sufficient, so that the reliability of the work is improved.

[0013]

Embodiments of the present invention will be described below with reference to the drawings. 1 shows a pipe joint according to an embodiment of the present invention, a partially cutaway side view of a tube being connected, FIG. 2 is a partially cutaway side view of the tube not connected, and FIG. 3 shows a tube. It is a partially broken side view of the connected state.

In FIG. 1, reference numeral 1 denotes a pipe joint of the present invention, which is composed of a joint body 2 and a sleeve 3. Four
Is the tube being connected.

The joint body 2 is made of metal (for example, brass is electrolessly Ni-plated) or the like, and has an inner cylindrical portion 5
And an outer tubular portion 6, and an annular sleeve insertion groove 7 is provided between the inner tubular portion 5 and the outer tubular portion 6.
A thin-walled tube fitting tubular portion 8 is integrally provided along the inner peripheral portion of the inner tubular portion 5. The continuous portion 9 of the tube fitting tubular portion 8 and the inner tubular portion 5 has an arcuate surface that gradually becomes thicker from the base side of the tube fitting tubular portion 8 to the inner tubular portion 5 side. The strain force is prevented from being concentrated. On the outer peripheral surface of the tube fitting tubular portion 8 at a position closer to the tip end side, a locking claw portion 10 is integrally projected in an annular shape.

As shown in FIG. 2, the locking claw portion 10 has a tapered guide surface 11 that gradually becomes thicker from the front end side to the rear side of the tube fitting tubular portion 8.
The rear end has a locking surface 12 that is substantially perpendicular to the axis. The interval between the outer peripheral surface of the tube fitting tubular portion 8 and the extended surface of the outer peripheral surface of the inner tubular portion 5 is set to be substantially equal to the wall thickness of the tube 4 described later. Further, a stopper 7a is projected radially inward at the opening side end of the sleeve insertion groove 7 in a state of integrally extending from the outer tubular portion 6.

In the joint body 2, a flow passage 1 formed inside the tube fitting tubular portion 8 and subsequently to the other end is opened.
3 is formed, the flow path 13 has two step portions 14 on the inner circumference of the intermediate portion of the inner tubular portion 5, and the tube fitting tubular portion 8 side is set to have a slightly smaller diameter.

On the side of the joint body 2 opposite to the tube connection side, the outer shape is formed to be thinner than the outer tubular portion 6, and a flange 15 is formed on the outer periphery of the end portion side. The inside of the flange 15 may come into contact with the end surface of the outer tubular portion 6 O
A ring 16 is provided. Flange 15 and O-ring 16
The pipe joint 1 is attached to the target device by using the above.

The sleeve 3 is made of a transparent resin such as polycarbonate and has an inner diameter that fits into the outer diameter of the inner tubular portion 5 and is slidable, and is substantially equal to the outer diameter of the tube 4. The outer diameter can be inserted into the inner diameter of the outer tubular portion 6, and a stopper 3a is projecting outward in the radial direction in a state of integrally extending in a ring shape at the end portion. The outer diameter of the stopper 3a is substantially equal to the inner diameter of the outer tubular portion 6,
Alternatively, the diameter is set to be slightly smaller. Further, a concave portion 3b is provided on the outer circumference of the sleeve 3 so that the sleeve 3 can be easily operated by pinching it with a fingertip.

The length of the sleeve 3 is set to be slightly shorter than the sum of the length of the inner tubular portion 5 and the length of the tube fitting tubular portion 8. It has tapered portions 17 and 18 that gradually expand as they reach each other.

The tube 4 is made of, for example, conductive urethane and has flexibility.

The sleeve 3 is mounted in the sleeve insertion groove 7 as shown in FIG.

The operation of connecting the tube 4 having the above structure will be described. First, the sleeve 3 is moved in the direction of arrow A in FIG.
It is placed at a position as shown in FIG. One end of the tube 4 is inserted into the outer periphery of the tube fitting tubular portion 8.
At this time, the tube 4 has flexibility, the locking claw portion 10 of the tube fitting tubular portion 8 has the guide surface 11 on the tube insertion side, and the sleeve 3 has the tapered portion 1.
Since 8 is provided, insertion and fitting can be performed relatively easily. Further, since the sleeve 3 is made of a transparent material, the tip of the tube 4 has a connecting portion 9 at a predetermined position.
It is possible to visually check whether the insertion and fitting state has been reached. This state is the state shown in FIG.

Thereafter, the sleeve 3 is placed in the sleeve insertion groove 7 along the surface of the inner tubular portion 5 and the outer surface of the tube 4 as shown in FIG.
3 in the direction of arrow B until the stopper 3a of the sleeve 3 is brought into contact with and locked by the stopper 7a of the sleeve insertion groove 7 to obtain the state of FIG. This operation is easy to carry out because the concave portion 3b provided on the outer circumference of the sleeve 3 facilitates gripping by the operator.

The state of FIG. 3 is obtained after performing such an operation. Since the inner diameter of the sleeve 3 reaches the position of the locking claw portion 10 of the tube fitting tubular portion 8, the tube 4
By utilizing its flexibility, the hook can be held in a retaining state that bites into the locking claw portion 10. Since the locking claw portion 10 has the locking surface 12 that is substantially orthogonal to the axial direction inside thereof as described above, this locking claw portion 1
By setting 0, the tube 4 can be reliably held in the retaining state.

When the tube 4 is to be replaced, the sleeve 3 is operated in the direction of arrow A, and the tip of the sleeve 3 is moved to a position where it abuts against the innermost surface of the sleeve insertion groove 7. In this operation, the tapered portion 17 provided at the tip of the sleeve 3 easily gets over the end portion of the inner tubular portion 5, and the concave portion 3b provided at the outer periphery of the sleeve 3 facilitates gripping by the operator. , Is easy to implement. Then, pull out the tube 4 and remove it. Even after the tube 4 is removed, the stopper 3a of the sleeve 3 does not come off or get lost because the stopper 3a thereof is abutted and locked by the stopper 7a of the sleeve insertion groove 7.

The pipe joint 1 is connected, for example, between a fine speed cylinder and a switching valve. At this time, the tube 4 may be connected to the pipe joint 1 in advance, or may be connected to the pipe joint 1 after connecting the pipe joint 1 to a fine speed cylinder or the like. Even when a force is applied to the tube 4 in the lateral direction at the time of connection, use, etc., the sleeve 3 fitted to the tube 4 has the end portion as described above on the outer periphery of the inner tubular portion 5. Since the tube fitting tubular portion 8 is fitted to the base portion, the strain force is prevented from concentrating on the base portion of the tube fitting tubular portion 8 to prevent the breakage.

A male screw, a swivel nut or the like may be used on the side of the connection with a desired device such as a fine speed cylinder, and the flow passage 13 is not limited to a straight line, and both ends may be opened in a right angle direction. it can. In addition, the present invention can be modified in various ways without departing from the basic technical idea thereof.

[0029]

As described above, according to the present invention, the outer cylindrical portion at the opening side end portion of the sleeve insertion groove of the joint body and the end portion of the sleeve on the innermost side of the sleeve insertion groove are provided. In the above, since both stoppers are engaged with each other when the stopper is projected and the sleeve is slid to operate in the direction away from the joint body, the sleeve does not separate from the joint body, and there is a risk of loss. Since there is no such thing, it is possible to concentrate on the work with confidence even in the case of replacement work.
Tube insertion and mounting can be performed easily and easily with few operation steps.

Further, by forming the sleeve with a transparent material or a semi-transparent material, it is possible to visually confirm whether the inserted state of the tube has reached a predetermined dimension,
Since it can be determined whether or not the insertion is sufficient, the certainty of the work is improved.

[Brief description of drawings]

FIG. 1 is a partially cutaway sectional view showing a pipe joint according to an embodiment of the present invention, showing a state where a tube is being connected.

FIG. 2 is a partially cutaway cross-sectional view showing a pipe joint according to an embodiment of the present invention and showing a state in which a tube is not connected.

FIG. 3 is a partially cutaway sectional view showing a pipe joint according to an embodiment of the present invention and showing a state after connecting tubes.

FIG. 4 is a partially cutaway cross-sectional view showing a conventional pipe joint and having tubes connected thereto.

[Explanation of symbols]

1 Pipe fitting 2 Joint body 3 sleeves 3a stopper 4 tubes 5 Inner tubular part 6 Outer tubular part 7 Sleeve insertion groove 7a stopper 8 Tube fitting tubular part 10 Locking claw

Claims (2)

[Claims] 1. An inner peripheral portion of the inner tubular portion having an inner tubular portion and an outer tubular portion on one end side, and an annular sleeve insertion groove provided between the two tubular portions. And a fitting main body including a tube fitting tubular portion having a locking claw portion on the outer peripheral surface subsequent to the portion, and fitted to the outer peripheral portion of the tube fitted to the outer peripheral portion of the tube fitting tubular portion. And the end portion is slidably fitted to the inner tubular portion in the sleeve insertion groove, the tube is fitted to the tube fitting tubular portion, and then the sleeve is slid. A sleeve for holding the tube in a retaining state such that the inner surface of the tube bites into the locking claw portion of the tube fitting tubular portion, and an outer tube at the opening side end of the sleeve insertion groove of the joint body. On the end of the sleeve on the innermost part of the groove and the groove for inserting the sleeve. , Respectively are protruded stopper, when operating the joint body and the sleeve in the detaching direction, by the two stoppers are engaged, pipe fitting, characterized in that to prevent falling off of the sleeve. 2. The pipe joint according to claim 1, wherein the sleeve is made of a transparent material or a translucent material.