JPH0631670B2 - Double pipe connection method - Google Patents

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method of connecting a double pipe having flexibility to supply a pressure fluid to a fluid actuator such as a cylinder, and more specifically, to a double pipe connection method. The present invention relates to a method for connecting a double pipe to a connector having a concave hole in which a chuck member for holding an outer pipe is provided.

(Prior Art) Conventionally, as seen in Japanese Utility Model Laid-Open No. 61-28989, a connector in which a connecting pipe having an annular projection on the outer periphery of the tip end is planted at the bottom of a concave hole containing a chuck member is used.
The connecting end of the heavy pipe is inserted into the concave hole of the connector, the inner pipe is externally fitted to the connecting pipe, and in this state, the outer pipe is gripped by the chuck member to connect the inner pipe and the outer pipe to the connector. It is known that it is to be pulled out.

(Problems to be Solved by the Invention) By the way, a double pipe is generally constructed by simply inserting an inner pipe into an outer pipe, and the inner pipe is not centered with respect to the outer pipe. When inserting the connecting end into the concave hole of the connector,
The inner pipe may be misaligned and may not fit onto the connecting pipe well, and when the fluid supply pressure is high, the inner pipe expands radially and tries to contract in the axial direction. I may get out.

In order to solve such a problem, it may be possible to form the double pipe by an extrusion molded product having a rib that connects the inner pipe and the outer pipe, but with this, the flexibility of the double pipe is impaired by the rib, The ease of handling of the pipes deteriorates, and the inner pipe expands radially in the circumferential portion where there are no ribs, creating a gap on the outer periphery of the connecting pipe, which may cause fluid to leak. It would be desirable to have a tubing that could be connected to a connector without the above disadvantages.

An object of the present invention is to provide a connecting method for double pipes that meets such a demand.

(Means for Solving the Problems) In order to achieve the above-mentioned object, the present invention is a check member for gripping a flexible double tube composed of an inner tube and an outer tube with an outer tube of the double tube. A method for connecting a connector having a recessed hole in which an inner portion of the double tube is connected to an outer pipe in a state in which the inner pipe of the double pipe is externally fitted to a connecting pipe having an annular projection of an outer periphery of a tip end portion planted at the bottom of the recessed hole. In a structure in which a pipe is gripped by the chuck member, a tubular portion externally fitted to a portion of an inner pipe externally fitted to the connecting pipe and a fitting part internally fitted to the outer pipe at a connection end portion of the double pipe to the connector. It is characterized in that the connecting end portion is inserted into the concave hole in a state where a spacer having a portion is attached.

(Operation) At the connecting end of the double pipe, the inner pipe is centered and held by the outer pipe through the spacer, and when inserting the connecting end into the concave hole of the connector, the inner pipe is not misaligned, and The inner pipe can be securely fitted onto the connecting pipe.

Also, the inner pipe portion that is externally fitted to the connecting pipe is tightened over the entire circumference by the cylindrical portion of the spacer that is externally fitted to the connecting pipe, and the annular projection of the connecting pipe strongly digs into the inner peripheral surface of the inner pipe. Even if the fluid supply pressure is increased, the inner pipe does not come off from the connecting pipe, and the fluid does not leak from the fitting portion of the inner pipe and the connecting pipe.

(Example) Referring to FIG. 1, (1) shows an outer tube (1a) made of a flexible tube and an inner tube also made of a flexible tube.
Double tube constructed by inserting (1b), (2) shows a connector, and a concave hole (3) capable of receiving the double tube (1) in the connector (2)
And a chuck member (4) for gripping the outer tube (1a) is provided in the recessed hole (3), and the outer periphery of the tip end portion in the center of the bottom of the recessed hole (3), that is, the outer periphery of the upper end portion in the drawing, is formed. A connecting pipe (5) having an annular protrusion (5a) is planted, an inner pipe (1b) is fitted onto the connecting pipe (5), and the fluid supplied via the inner pipe (1b) is connected to the connecting pipe (5). Supply to a fluid passage (not shown) connected to the pipe (5)
A guide sleeve (6) into which the outer pipe (1a) can be inserted is provided around the connecting pipe (5) at the bottom of (3), and the fluid supplied through the outer pipe (1a) is supplied to the sleeve (6). Notch (6a) formed in the lower end of the
Fluid passage (7) opened at the periphery of the bottom surface of the concave hole (3) via
To be supplied to.

The chuck member (4) includes a collect (9) fitted inside a sleeve (8) fitted and fixed to the upper end of the recessed hole (3), and the collect (9).
A split claw that can be attached to the outer tube (1a) at the lower end fitted inside (9)
A chuck cylinder (10) having (10a) and a ring-shaped elastic member (11) in which the collar (12a) fitted in the chuck cylinder (10) is pushed down to place the split claw (10a) on its lower surface. And an operating sleeve (12) that pushes downward against the above.

Here, as shown in FIGS. 2 and 3, the connecting end portion of the double pipe (1) to the connector (2) is attached to the outer periphery of the cylindrical portion (13a) which is externally fitted to the inner pipe (1b). Rib-shaped part that fits inside the outer tube (1a)
Spacers (13) formed by radially protruding a plurality of (13b) are to be mounted, and this part is designed to facilitate this mounting work.
The outer edge of (13b) was inclined inward in the radial direction toward the front in the insertion direction.

As the spacer (13), as shown in FIGS. 4 and 5, a tubular portion (13a) externally fitted to the inner pipe (1b) and a tubular contact portion (internally fitted to the outer pipe (1a) ( It is also possible to use a double cylindrical shape having 13b) and a flange (13c) that integrates both parts (13a) and (13b). In this case, the flange (13c) is connected to the outer pipe (1a) from the outer tube (1a). A through hole (13d) through which the supplied fluid passes is formed.

When connecting the double pipe (1) to the connector (2), the spacer (13) is attached to the connecting end of the double pipe (1) so that the cylindrical portion (13a) of the spacer (13) is fitted onto the connecting pipe (5). After bonding the tip of the pipe (1b) so that it fits externally, the connecting end is inserted into the concave hole (3) of the connector (2). According to this, the end of the inner pipe (1b) Make sure that the part is centered on the spacer (13) and fit securely onto the connecting pipe (5).
A check cylinder that forms a check member (4) on the outer peripheral surface of (1a)
The split claw (10a) of (10) bites, and the outer tube (1a) is retained in the concave hole (3).

In this connection state, the end portion of the inner pipe (1b) is tightened over the entire circumference by the tubular portion (13a) of the spacer (13) fitted onto the inner pipe (1b), and the annular projection (5a) of the connecting pipe (5) is Even if the inner pipe (1b) strongly digs into the inner peripheral surface and the fluid supply pressure is increased, the inner pipe (1b) may come out of the connecting pipe (5), or the inner pipe (1b) and the connecting pipe (5). The fluid does not leak from the fitting portion with.

(Effects of the Invention) As described above, according to the present invention, the spacer mounted on the connecting end portion of the double pipe can surely fit the outer pipe onto the connecting pipe in a state where the inner pipe is centered, and the connecting workability is improved. In addition, the pressure resistance against the disconnection of the inner pipe and the leakage of fluid is enhanced, and since the spacer is simply attached to the connecting end of the double pipe, 2
It also has the effect of not impairing the flexibility of the heavy pipe.

[Brief description of drawings]

FIG. 1 is a cross-sectional view of an essential part of a connector to which a double pipe is connected by the method of the present invention, FIG. 2 is a vertical cross-sectional view of a connecting end of a double pipe having a spacer, and FIG. III-III line cross-sectional view, FIG. 4 is a vertical cross-sectional view of a modification of the spacer, and FIG. 5 is a VV line cross-sectional view of FIG. (1) …… Double tube, (1a) …… Outer tube (1b) …… Inner tube, (2) …… Connector (3) …… Recessed hole, (4) …… Check member (5) …… Connection pipe, (5a) …… annular protrusion (13) …… spacer, (13a) …… cylindrical part (13b) …… this part

 ─────────────────────────────────────────────────── ─── Continuation of the front page (56) Reference JP 61-130697 (JP, A) Actually open 61-28989 (JP, U) Actually open 57-75030 (JP, U)

Claims (1)

[Claims] 1. A method of connecting a flexible double tube composed of an inner tube and an outer tube to a connector having a recessed hole in which a chuck member for holding the outer tube of the double tube is provided. In the case where the outer pipe is gripped by the chuck member in a state where the inner pipe of the double pipe is externally fitted to the connecting pipe having the annular projection on the outer periphery of the tip end portion which is planted in the bottom of the recessed hole, The connecting end portion of the pipe is attached with a spacer having a tubular portion externally fitted to a portion of the inner pipe externally fitted to the connecting pipe and a corresponding portion fitting internally to the outer pipe. A method for connecting a double pipe, characterized in that the double pipe is inserted into a recess.