JPH116506A - Expansion pipe - Google Patents

Abstract

PROBLEM TO BE SOLVED: To facilitate an operation for loosening in the case of releasing tightening and fixing for outer and inner pipes. SOLUTION: An edge is formed in a boundary between a flat face and an outer wall of the circumferential direction by cutting out in parallel to the axial direction of a supporting part 5 the outer wall of the supporting part 5 of a locking body 3 fixed to a tip of an inner pipe 2 to form the flat face. A back face of an annular body 6 is brought into contact with an inner wall of an outer pipe 1 by rotating oppositely the outer pipe 1 and the inner pipe 2 so as to bring the annular body 6 fitted with an annular groove 51 in the circumferential direction of the supporting part 5 into contact with the inner wall of the outer pipe 1. At this time, a pressing force in the back face of the annular body 6 is dispersed to two edges of the supporting part 5, a weld scar (bead) is difficult to be bitten in even when one of the edge of the supporting part 5 is located in the weld scar (bead) of the inner wall of the pipe 1, and a bit-in portion is easy to be released at the time of loosening the outer pipe 1 and the inner pipe 2 so as to allow the loosening easily.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

TECHNICAL FIELD The present invention relates to a telescopic clothesline,
The present invention relates to a telescopic pipe used for a telescopic shelf or the like.

[0002]

2. Description of the Related Art Conventionally, as a telescopic pipe which is used by connecting two types of pipes so as to be able to expand and contract, for example, Japanese Utility Model Publication No. 55-30475 discloses a telescopic pipe having a locking member attached to an end of an inner pipe. An annular groove is formed in the support portion, and an annular body is slidably fitted in the groove.When connecting two pipes, one of the pipes is rotated in the circumferential direction to make the annular body shallow. A telescopic pipe is disclosed in which the back of the ring-shaped body and the outer wall of the support located on the opposite side of the back come into contact with and are locked to the inner wall of the outer pipe.

[0003] However, in such a conventional telescopic pipe, only two points, that is, the back of the annular body inserted into the support at the end of the inner pipe and the outer wall of the support located opposite to the back, correspond to the inner wall of the outer pipe. Since the outer pipe is thin, the outer pipe has a disadvantage that it is easily deformed when the outer pipe is thin. In addition, when there is a welding mark (bead) on the inner wall of the outer pipe, the outer wall of the support portion comes into contact with the welding mark (bead). Then, as the time elapses, the welding mark (bead) bites into the outer wall of the support portion, and there is a disadvantage that the bite portion is hard to come off even if the support portion is loosened in order to expand and contract the outer pipe and the inner pipe.

[0004]

SUMMARY OF THE INVENTION The present invention has been made to solve the above-mentioned problems, and an object of the present invention is to provide a telescopic pipe excellent in workability, in which a support bites into a welding mark (bead) during use.

[0005]

In order to achieve the above object, a telescopic pipe according to the present invention has a locking member fixed to a tip of an inner pipe which can be freely inserted into an outer pipe, and the locking member is provided in an end of the inner pipe. An annular groove is formed in the support portion, which has a width slightly smaller than the inner diameter of the outer pipe and has the same width in the circumferential direction and is gradually deepened toward the deepest portion in the circumferential direction. An annular body partially circumferentially separated from the annular groove is slidably fitted in the circumferential direction, and the annular body has a protruding portion formed inward from one end of the separated end. The thickness of the ring-shaped body other than the protruding portion is smaller than the depth of the annular groove, and a part of the outer wall of the support is cut out in parallel with the axial direction of the support to form a flat surface. A ridge is formed at the boundary between the surface and the outer wall in the circumferential direction.

In the telescopic pipe of the present invention, the flat surface of the support portion is formed at a position substantially facing the shallowest portion of the annular groove.

Further, in the telescopic pipe of the present invention, the fitting insertion portion of the locking body and the support portion are connected by a slidable shaft, and a coil spring is inserted through the shaft.

[0008]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. In the drawing, reference numeral 1 denotes an outer pipe, 2 denotes an inner pipe, 3 denotes a locking body composed of a fitting portion 4 and a support portion 5, and 6 denotes a ring-shaped body.

The outer pipe 1 is a long body having a circular cross section, such as a metal pipe such as stainless steel, aluminum, or brass, or a steel pipe coated with a synthetic resin such as polyethylene, polypropylene, ABS resin, or polyvinyl chloride. Is used. For the inner pipe 2, a metal pipe similar to the outer pipe 1 is used.

The locking member 3 is usually made of a synthetic resin such as ABS resin, polypropylene, polyamide or the like, and comprises a fitting portion 4 fitted into the end of the inner pipe and a supporting portion 5 substantially equal to the inner diameter of the outer pipe 1. .

An annular groove 5 having the same width in the circumferential direction and being gradually deeper in the circumferential direction toward the deepest portion 52 is formed in the support portion 5.
1 is formed, and a ring-shaped body 6 partly cut in the circumferential direction is fitted into the annular groove 51 so as to be slidable in the circumferential direction, and the ring-shaped body 6 faces inward from one end of the cut-off end. Protruding part 6
1 is formed, and the thickness of the ring-shaped body 6 other than the protruding portion 61 is smaller than the depth of the annular groove 51.

It is preferable that the height of the protruding portion 61 of the ring-shaped body 6 is made substantially equal to the depth of the deepest portion 52 of the annular groove 51 because there is no play in the circumferential direction of the ring-shaped body 6.

The support portion 5 has a flat surface 53 in which a part of the outer wall in the circumferential direction is cut out in parallel with the axial direction of the support portion 5, and the flat surface 53 and the outer wall in the circumferential direction are formed. Edge 54 at the border
Are formed. The shape of the flat surface 53 may be smooth, may be slightly curved, and the ridge 54 may be angular or slightly rounded.

If the center angle of the two ridges 54 exceeds 120 degrees, the contact position between the two ridges 54 and the inner wall of the outer pipe 1 is too far away, and if the center angle is less than 120 degrees, the support 5
And the inner wall of the outer pipe is stably abutted, which is preferable.

The fitting portion 4 and the support portion 5 of the locking body 3 may be integrated as shown in FIG. 1, or may be slidably connected via a shaft 31 as shown in FIG. In this case, either end of the shaft 31 may be fitted into the insertion portion 4 or the support portion 5.
And a coil spring 32 that separates the fitting portion 4 and the supporting portion 5 from each other is fitted into the shaft 31.

[0016]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An anchor 3 having a flat surface 53 formed on a support portion 5 as shown in FIG. 3 is fixed to the tip of an inner pipe and inserted into an outer pipe as shown in FIG. 1, and the inner pipe is rotated to form a ring-shaped body. The back face and the two ridges of the support part were in contact with the inner wall of the outer pipe.
In this case, the flat surface 53 was set so as to be located at a welding mark (bead) on the inner wall of the outer pipe. Eight such samples were set, left in this state for 4 days, loosened using a torque wrench, and the torque at that time was measured. As a result, the average value of the eight samples was 20.4 kgf.

For comparison, eight samples in which a telescopic pipe using a conventional locking portion having no flat surface was fixed in the same manner as in the above embodiment were set, and after leaving for 4 days, loosened using a torque wrench. The torque was measured. As a result, the average value of the eight samples was 29.4 Kgf, which was less loose and less operable than that of the above-described embodiment.

[0018]

As described in detail above, in the telescopic pipe of the present invention, the outer wall of the support portion of the locking member fixed to the tip of the inner pipe is cut out parallel to the axial direction of the support portion to form a flat surface,
Since the ridge is formed at the boundary between the flat surface and the outer wall in the circumferential direction, it is slidably fitted in the annular groove formed in the circumferential direction of the support portion and gradually deepened toward the deepest portion. The outer pipe and the inner pipe are rotated in opposite directions so that the ring-shaped body abuts against the inner wall of the outer pipe, and when the back surface of the ring-shaped body abuts the inner wall of the outer pipe, the pressing force on the back surface of the ring-shaped body Are dispersed on the two ridges of the support part, and even if one of the ridges of the support part is located at the weld mark (bead) on the inner wall of the outer pipe, the weld mark (bead) is hard to bite, and When the inner pipe is loosened, the bite portion easily comes off and can be easily loosened, and the three points of the back of the annular body and the two ridges of the support are abutted on the inner wall of the outer pipe, Even when the thickness of the outer pipe is thin, deformation of the outer pipe hardly occurs.

Further, in the telescopic pipe of the present invention, when the flat surface of the support portion is formed at a position almost facing the shallowest portion of the annular groove, the outer pipe and the inner pipe are slightly rotated when being fixed. Just tighten it and it is easy to operate.

Further, in the telescopic pipe according to the present invention, the outer pipe and the inner pipe are connected to each other when the insertion portion and the support portion of the locking body are connected by a slidable shaft and a coil spring is inserted through the shaft. It can be used by being stretched between two opposing surfaces within the range of the repulsive force of the coil spring.

[Brief description of the drawings]

FIG. 1 is a partially cutaway sectional view of one embodiment of an expansion pipe according to the present invention.

FIG. 2 is a partially cutaway sectional view of another embodiment of the telescopic pipe of the present invention.

FIG. 3 is a cross-sectional view of an example of a locking body used in the present invention.

FIG. 4 is a cross-sectional view showing a state where a ring-shaped body is fitted to a locking body used in the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Outer pipe 2 Inner pipe 3 Locking body 31 Shaft 32 Coil spring 4 Fitting part 5 Supporting part 51 Annular groove 52 Deepest part 53 Flat surface 54 Ridge part 6 Ring body 61 Projecting part

Claims (3)

[Claims] 1. A locking member is fixed to a tip of an inner pipe which can be inserted into an outer pipe. The locking member has a fitting portion to be inserted into the inner pipe and a support portion having a diameter slightly smaller than the inner diameter of the outer pipe. An annular groove having the same width in the circumferential direction and gradually deepening in the circumferential direction toward the deepest portion is formed in the support portion, and a ring-shaped body in which a part of the circumferential direction is cut off in the annular groove. Are fitted slidably in the circumferential direction, the annular body has a protruding portion formed inward from one end of the cut-off end, and the thickness of the annular body other than the projecting portion is smaller than the depth of the annular groove. A part of the outer wall of the support is cut out in parallel with the axial direction of the support to form a flat surface, and a ridge is formed at a boundary between the flat surface and the outer wall in the circumferential direction. Telescopic pipe. 2. The telescopic pipe according to claim 1, wherein the flat surface of the support portion is formed at a position substantially facing the shallowest portion of the annular groove. 3. The telescopic pipe according to claim 1, wherein the fitting portion of the locking body and the supporting portion are connected by a slidable shaft, and a coil spring is inserted through the shaft.