JPS6218726Y2 - - Google Patents

Description

[Detailed description of the invention] This invention relates to a retractable pipe used for clotheslines, motsupu handles, etc.

A small-diameter pipe is slidably inserted inside the large-diameter pipe, a camshaft is connected to the end of the small-diameter pipe, and a friction piece with an arcuate outer and inner circumference is fitted into an eccentric groove formed on the outer circumference of the camshaft. A conventional telescopic pipe in which this friction piece is brought into pressure contact with the inner periphery of the large diameter pipe and the groove bottom of the eccentric groove by rotating the small diameter pipe to lock the small diameter pipe at the adjusted position is conventional. Exists from

However, in the above telescopic pipe, the contact between the friction piece and the inner periphery of the large-diameter pipe and the contact between the friction piece and the bottom of the eccentric groove are line contacts, so there is a problem with the holding force that prevents the small-diameter pipe from sliding. There is.

The object of this invention is to improve the above-mentioned telescopic pipe in which the small diameter pipe is rotated and locked, and to provide a telescopic pipe that can reliably prevent the small diameter pipe from sliding.

The structure of this invention is that a tapered shaft is provided at the end of a small-diameter pipe that is slidably inserted inside a large-diameter pipe, and a spiral annular friction member that has a radial cutout in a spiral groove formed on the outer periphery of this tapered shaft. The inner periphery of the plate is fitted, the outer diameter of the friction plate is approximated to the inner diameter of the large-diameter pipe, and by rotating the small-diameter pipe, the diameter of the friction plate is expanded, and the entire outer periphery of the friction plate is expanded. is pressed against the inner periphery of a large-diameter pipe.

Hereinafter, embodiments of this invention will be described based on the accompanying drawings.

As shown in the figure, a small diameter pipe 2 is slidably inserted inside a large diameter pipe 1, and a tapered shaft 3 is connected to an end of the small diameter pipe 2 located inside the large diameter pipe 1.

The tapered shaft 3 is a taper whose outer diameter gradually increases toward the tip, and a flange 4 is provided at the tip. Further, a spiral groove 5 is formed on the outer periphery of the tapered shaft 3, and an inner peripheral portion of an annular friction plate 6 is fitted into this spiral groove 5.

The annular friction plate 6 is provided with a radial cutoff portion and can be fitted into the helical groove 5 from the side of the tapered shaft 3. Furthermore, the friction plate 6 is formed into a spiral shape so that its inner peripheral portion fits into the spiral groove 5 .

Furthermore, the friction plate 6 is molded from synthetic resin, and its outer diameter approximates the inner diameter of the large-diameter pipe 1, so that it lightly contacts the inner circumference of the large-diameter pipe 1, and the small-diameter pipe 2
It is designed so that it does not rotate together with this small diameter pipe 2 when it rotates.

By the way, since the groove width at both ends of the spiral groove 5 formed on the outer periphery of the tapered shaft 3 is gradually decreasing, if the small diameter pipe 2 is rotated more than necessary, the ends of the friction plate 6 will become stuck in the spiral groove 5. It may get stuck in the narrow parts at both ends. Therefore, in order to prevent this, stopper portions 7 are provided at both ends of the spiral groove 5 to prevent the friction plate 6 from coming off.

Now, after adjusting the length of the telescopic pipe by sliding the small-diameter pipe 2, when the small-diameter pipe 2 is rotated relative to the large-diameter pipe 1, it comes into contact with the inner circumference of the large-diameter pipe 1 and comes to a halt. A certain friction plate 6
The tapered shaft 3 moves in the axial direction. Therefore, when the large diameter part of the tapered shaft 3 is moved toward the inner circumference of the friction plate 6, the diameter of the friction plate 6 gradually expands, the outer circumference comes into pressure contact with the inner circumference of the large diameter pipe 1, and the inner circumference of the friction plate 6 gradually increases. Since the peripheral portion comes into pressure contact with the bottom of the spiral groove 5, the small diameter pipe 2 is held at the slide adjusted position.

When the small-diameter pipe 2 is rotated in the opposite direction to move the small-diameter portion of the tapered shaft 3 toward the inner circumferential portion of the friction plate 6, the friction plate 6 contracts due to its own elasticity and locks. is released, and the small diameter pipe 2 can be slid arbitrarily.

As described above, in this invention, when a small-diameter pipe is rotated, the taper shaft moves in the axial direction relative to the friction plate, causing the friction plate to expand or contract in diameter. Since the entire inner periphery is in pressure contact with the inner periphery of the large diameter pipe and the bottom of the spiral groove, the small diameter pipe The force for preventing movement is large, and the movement of the small diameter pipe can be reliably prevented.

In addition, a stopper part is provided at the end of the spiral groove to prevent the friction plate from slipping out, so when the small diameter pipe is rotated more than necessary, the end of the friction plate will bite into the narrowed end of the spiral groove. There is no inconvenience of getting stuck in the shaft, and it can be inserted inside a large diameter pipe with the friction plate attached to the spiral groove of the tapered shaft.
Assembly work is also easy.

[Brief explanation of the drawing]

Fig. 1 is a partially cutaway perspective view showing an embodiment of the telescopic pipe according to the invention, Fig. 2 is a perspective view showing the end of the same small diameter pipe, and Fig. 3 is an enlarged view of the main parts of the same. FIG. 1...Large diameter pipe, 2...Small diameter pipe, 3...
Tapered shaft, 5... spiral groove, 6... friction plate, 7...
Stoppa part.

Claims (1)

[Scope of utility model registration request] It consists of a large-diameter pipe and a small-diameter pipe slidably inserted inside the large-diameter pipe, and a tapered shaft is provided at the end of the small-diameter pipe located inside the large-diameter pipe, and the outer circumference of the tapered shaft is forming a spiral groove, fitting the inner peripheral part of a spiral annular friction plate having a radial cut-off part into the spiral groove, and making the outer diameter of the friction plate approximate the inner diameter of the large diameter pipe; The extensible pipe is provided with a stopper part for preventing the friction plate from coming off at the end of the spiral groove.