JPH0529234Y2 - - Google Patents

Description

[Detailed description of the invention] (Technical field to which the invention belongs) The present invention relates to a retractable hollow pipe for constructing sand piles.

(Problems with the invention and its features) An inner tube with teeth on its upper and lower outer circumferential surfaces, an outer tube with teeth on its upper outer circumference, and teeth that mesh with the teeth on its inner circumferential surface. A retractable hollow tube for constructing sand piles equipped with a band (joint body) is conventionally known (see Japanese Patent Publication No. 35685/1983).

Band (joint body) in this conventional example
It consists of a pair of half-split bodies connected by a pivot on one side, and when changing the length of the hollow tube, it must be removed from the hollow tube, which is inconvenient in handling. .

The present invention aims at improving the conventional example, and its structural features are as described in the claims of the utility model registration.

That is, in the present invention, the band is composed of a pair of half-band members bolted together on both sides, and these half-band members are attached via hinges at symmetrical positions on the outer circumference of the upper end of the outer tube. This makes it easier to handle.

(Specific explanation of the invention based on the drawings) In the drawings, 1 is a hollow tube main body, which is composed of an inner tube 2 and an outer tube 3 so as to be expandable and retractable.

A plurality of teeth 4 are provided on each of the upper and lower outer peripheral surfaces of the inner tube 2, which is slidably inserted into the outer tube 3 from above, and a plurality of teeth 4 are provided on the outer circumference of the upper end of the outer tube 3. 5 is provided.

The band 6 for connecting the inner tube 2 and the outer tube 3 is
1 with teeth 7 and 8 that mesh with teeth 4 and 5 on the inner peripheral surface
It consists of a pair of half-band bodies 9, 9', and these half-band bodies 9, 9' have bolts 10, 10 on both sides.
It is designed to be joined by

The half band members 9, 9' are attached to symmetrical positions on the outer periphery of the upper end of the outer tube 3 via hinges 11, 11', respectively.
1' is composed of a pin 12 attached to the lower part of one side of the half band members 9 and 9', and a short tube 14 attached to the outer tube 3 via a plate 13. A locking nut 15 is screwed on.

The pin hole of the short tube 14 may have the same shape (circular) as the pin 12, but it is convenient to form it into a long hole that is long in the tangential direction of the outer tube 3, since this improves the tightening effect of the bolt 10.

Numeral 16 is a packing fitted to the joint between the inner tube 2 and the outer tube 3, and prevents leakage of compressed air supplied to the main body 1 to improve sand removal.

17 is a pipe that supplies jet water to the outer periphery of the lower end of the outer tube 3, and is a pipe 17 that connects the pipe 17' disposed inside the inner tube 2, the pipe 17'' disposed outside the outer tube 3, and the pipe 17 connecting these. When the main body 1 is in the contracted state, the upper end of the pipe 17 is connected to a pipe joint (not shown) at the upper end of the pipe 17'.

FIG. 1A shows a state in which the main body 1 is extended, that is, a state in which the lower teeth 4 of the inner tube 2 are engaged with the teeth 7 of the band 6 to connect the inner tube 2 and the outer tube 3. In order to make the main body 1 contracted from this state, remove the pipe 17 and bolts 10, 10 as shown in FIG.
, move inner tube 2 downward, and now inner tube 2
The upper teeth 4 (not shown) may be engaged with the teeth 7 to perform the connection. During this time, the half band members 9, 9' are supported by the outer tube 3 via the hinges 11, 11'. It remains as it is.

(Effect of the invention) The retractable hollow pipe for constructing sand piles of the present invention is as described above, and the band connecting the inner pipe and the outer pipe can be opened and closed while being attached to the outer pipe. Therefore, there is no inconvenience in handling the band as in the conventional case, and the hinges of each half-band body are located at two symmetrical locations, making it easy to open and close even if the hinges are placed close to the outer periphery of the outer tube. This has the advantage that when the band part goes underground, the holes that are formed are small and there is little loss of sand.

[Brief explanation of drawings]

The drawings are explanatory diagrams of one embodiment of the present invention, in which FIGS. 1A and B are perspective views of the main parts, FIG. 2 is a plan view showing the state in which the band is attached, and FIG.
It is an arrow view. 2...Inner pipe, 3...Outer pipe, 4, 5...Teeth, 6...
... band, 7, 8 ... teeth, 9, 9' ... half-split band body, 10 ... bolt, 11, 11' ... hinge, ...

Claims (1)

[Claims for Utility Model Registration] (1) An inner tube with teeth on its upper and lower outer circumferential surfaces, an outer tube with teeth on its upper outer circumference, and teeth that mesh with the teeth on its inner circumferential surface. In a retractable hollow pipe for constructing sand piles, the band is composed of a pair of half-band bodies bolted together on both sides, and each half-band body is attached to the outer circumference of the upper end of the outer pipe. A retractable hollow pipe for constructing sand piles, characterized in that the hollow pipes are attached at symmetrical positions via hinges. (2) The retractable hollow pipe for constructing sand piles according to claim (1), wherein the pin hole of the hinge is a long hole extending in the tangential direction of the outer pipe.