JPS6337525Y2 - - Google Patents

Description

[Detailed explanation of the invention] This invention is a telescopic pipe, specifically, it is installed in a closet etc. and used as a support for hanging clothes, between a chest of drawers and a wall and used as a curtain rail, and furthermore, it is installed between opposing walls in a hallway. This relates to a telescopic tube that can be used for a variety of purposes, including as a clothesline.

Conventionally, as this type of telescopic tube, one described in Japanese Utility Model Publication No. 56-878 has been known. That is, as shown in FIG. 1, this telescopic tube has an outer tube 1, an inner tube 2 that can be freely inserted into the outer tube 1, and is inserted inside the outer tube 1 and the inner tube 2, with one end being large. The diameter portion 5 is caulked and fixed inside one end of the outer cylinder 1, and the other end 6 is tightly fixed to the coil spring 3 which is unwound to the one end side, and is fixed in the inner cylinder 2 so as to extend in the diametrical direction. It consists of a shaft 7 which is threadably engaged with the spring 3, and an elastic cap 10 which is attached to the outer ends of the outer cylinder 1 and the inner cylinder 2 so as to cover at least the caulked part 9.
By rotating the outer cylinder 1 and the inner cylinder 2, the shaft 7 slides on the helical surface of the coil spring 3, and the inner cylinder 2 can move in and out of the outer cylinder 1. By compressing the inner cylinder 2 and the inner cylinder 2 in opposite directions, the telescopic tube can be attached between the two objects.

However, in the case of this telescopic tube, the guide portion that engages with the coil spring 3 is the shaft 7 extending in the diametrical direction of the inner tube 2, so even in an unloaded state, the shaft 7 has a force in the direction of the arrow in FIG. Moment acts constantly, and not only can the shaft 7 not slide smoothly on the coil spring 3, but also the shaft 7 or the coil spring 3 is severely worn.
In addition, since the tip 6 of the coil spring 3 is wound back to the other end to prevent the shaft 7 from falling off, the shaft 7 is fixed to the inner cylinder 2 with the coil spring 3 inserted into the inner cylinder 2. Therefore, the manufacturing and assembly work was extremely troublesome.

The present invention was devised in view of these conventional drawbacks.The purpose of the present invention is to enable the guide portion formed in the inner cylinder to slide smoothly with the coil spring, reduce wear, and make the telescopic tube easy to manufacture and assemble. Our goal is to provide the following.

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below with reference to the accompanying drawings showing embodiments thereof.

FIGS. 2 and 3 show an example of an extensible tube according to the present invention, and this extensible tube includes an outer tube 11, an inner tube 13, a cap 15 made of an elastic material such as rubber, and a coil spring 16, as in the conventional tube. ing.

_This coil spring 16, as shown in FIG. pitch _P2 , and therefore the coil spring 17 on the outer cylinder side has a smaller spring constant (repulsive force) than the other coil spring 18. At the tip of the coil spring 17 on the outer cylinder side,
A hook 17a is formed to be fixed to the fixed shaft 12 fixed to the outer end of the outer cylinder 11, and the tip 18a of the other coil spring 18 terminates while maintaining a constant lead angle. The inner cylinder 13 is attached to the helical surface of the coil spring 18 with a large pitch.
Cut and raised piece 14 which is a guide part formed on the tip edge of
(see FIGS. 5 and 6) are in sliding contact with each other, and the inclination angle of this cut and raised piece 14 is determined by the angle of inclination of the coil spring 1.
It is equal to the lead angle of 8. Therefore, when the inner cylinder 13 is rotated in either direction, the cut and raised pieces 14 smoothly slide into contact with the coil spring 18, and the inner cylinder 1
3 protrudes from or retracts from the outer cylinder 11. In order to assemble this telescopic tube, the inner tube 13 may be inserted into the opening of the outer tube 11 while being rotated clockwise. That is, as the cut and raised piece 14 rotates, it naturally engages with the tip 18a of the coil spring 18, and the cut and raised piece 14 is guided inward while slidingly contacting the helical surface of the coil spring 18. Note that when the inner cylinder 13 is retracted to a predetermined position, the cut and raised pieces 14
Since this contacts the screw member 19, further retraction of the inner cylinder 13 is restricted.

Now, when the outer cylinder 11 and the inner cylinder 13 are compressed in opposite directions, the coil spring located between the fixed shaft 12 and the raised piece 14 is pressed, but the coil spring 17 with a smaller pitch has a smaller pitch. Since the spring constant is smaller than the large coil spring 18, only the small pitch coil spring 17 is compressed and the large pitch coil spring 1 is compressed.
8 is hardly compressed.

In other words, the repulsive force acting on the outer cylinder 11 and the inner cylinder 13 depends only on the spring force of the coil spring 17 with a small pitch, and the repulsive force acts on the outer cylinder 11 and the inner cylinder 13 depending on whether the inner cylinder 13 is recessed or protruded from the outer cylinder 11. The repulsive force remains almost unchanged. Therefore, no matter what the distance between the two objects, the telescopic tube can always be easily attached with a constant force.

In the above embodiment, when the outer cylinder 11 and the inner cylinder 13 are compressed in opposite directions, a very large pressing force acts on the cut and raised pieces 14, and there is a risk that the cut and raised pieces 14 may be deformed. However, since the outer diameter of the coil spring 18 is set to be approximately equal to the inner diameter of the inner cylinder 13, the strands of the coil spring 18 are pressed against the root part of the cut and raised piece 14, and the cut and raised piece 14 is pressed against the root of the inner cylinder 13. Approximately 1/3 of the entire circumference is cut up, so
The strength of the cut and raised piece 14 as a whole is high, so there is no fear that the cut and raised piece 14 will be deformed.

Further, the cut and raised piece 14 may be formed by cutting and raising the middle part of the inner cylinder 13 inward, but this method is troublesome to process, and when the inner cylinder 13 is made to protrude from the outer cylinder 11, The maximum overall length of the expandable tube is shorter than that of a tube in which the cut and raised piece 14 is provided at the tip edge. For this reason, the cut and raised piece 14 is provided at the tip end edge of the inner cylinder 13.

As is clear from the above explanation, according to the present invention, the cut and raised pieces are formed by cutting and raising the tip edge of the inner cylinder along the helical surface of the coil spring with a large pitch. It slides effortlessly and smoothly with the coil spring, making it easy to rotate the inner cylinder and reducing wear on the cutting pieces and coil spring. Furthermore, when assembling, if the inner cylinder is rotated and inserted into the outer cylinder, the cut and raised pieces and the coil spring will naturally engage with each other, so assembly is simple and the process of the cut and raised pieces is also extremely easy. Furthermore, since the repulsive force is always obtained from a coil spring with a small pitch, the telescopic tube can be easily attached to the wall surface with a constant force regardless of the length of the telescopic tube.

[Brief explanation of the drawing]

Fig. 1 is a vertical cross-sectional view of a conventional telescopic tube, Fig. 2 is a front view of a telescopic tube according to the present invention, Fig. 3 is a cross-sectional view thereof, Fig. 4 is a vertical cross-sectional view of a coil spring, and Fig. 5 is a longitudinal cross-sectional view of a conventional telescopic tube.
6 are a perspective view and a sectional view of the end of the inner cylinder. DESCRIPTION OF SYMBOLS 11... Outer cylinder, 13... Inner cylinder, 14... Cut-off piece, 15... Cap, 16, 17, 18... Coil spring.

Claims (1)

[Scope of utility model claims] an outer cylinder, an inner cylinder that can be freely inserted into the outer cylinder, a coil spring that is inserted inside the outer cylinder and the inner cylinder and has one end fixed inside one end of the outer cylinder, and an inside of the inner cylinder. A telescopic tube consisting of a guide portion that protrudes from the tube and is threadably engaged with the coil spring, and an elastic cap that is fitted to the outer ends of the outer tube and the inner tube, the coil spring being the same. It is composed of a coil part with a small pitch and a coil part with a large pitch, and the outer end of the coil part with a small pitch is fixed to the outer cylinder, while the guide part is connected to the coil part with a large pitch. A telescoping tube characterized in that it is constructed with a cut-and-raised piece in which the inner end edge of the inner cylinder is cut and raised inward so as to follow a spiral surface.