JPH0332638Y2 - - Google Patents

Description

[Detailed explanation of the invention] - Industrial application field This invention involves drilling a vertical hole from the ground, then drilling a hole horizontally within the vertical hole using an auger, and then inserting a resin pipe into the tip of the auger. This relates to a jig that is used when pulling a resin pipe into a horizontal hole while connecting the tips of the auger and retracting the auger.

・Prior art and its problems A cable grip as shown in FIG. 3 is known as a method for connecting a traction wire or the like to a pipe without processing the pipe when the pipe is drawn into a hole.

However, although this cable grip has a high gripping force and is easy to use, when pulling the pipe into a hole excavated in the soil, it is necessary to bring the outside diameter of the hole and the pipe as close as possible. When using a burying method that prevents gaps between the pipe and the hole, the cable grip portion becomes considerably larger than the outer diameter of the pipe, which may cause the hole to collapse or the diameter of the hole to be increased. This has the disadvantage of creating gaps.

One possible solution to the above drawback is to fit an insert tool into the tip of the tube and connect a traction tool to this insert tool.
In order to fit the insert tool into the tip of the pipe and resist the traction force, it is necessary to increase the frictional force between the pipe and the insert tool, and in the case of resin pipes, only the part where the insert tool is inserted The outer diameter of the tube is thicker than other tubes, and this thickening often becomes a problem when connecting to other tubes.

Furthermore, when a resin pipe is drawn into a hole in the ground, the outer circumferential surface on the tip side of the pipe is most likely to be damaged, and this damage will impede airtightness if it joins with another pipe.

・Purpose of this invention This invention is proposed in view of the above points.
The first objective is to propose a drawing jig that does not damage or enlarge the hole previously drilled for drawing in the resin pipe. A second objective is to propose a drawing jig that does not damage the outer circumferential surface of the distal end of a resin pipe when drawing the resin pipe.

- Structure of the present invention As a means to achieve the above object, the present invention sets the outer diameter of the tip side to be approximately the same as the inner diameter of the resin tube, and sets the outer diameter of the rear end side to be slightly larger than the inner diameter of the resin tube. an insert with a step formed on the outer peripheral surface consisting of a large-diameter part and a small-diameter part, and a female thread cut in the center of the distal end; We propose a jig for drawing a resin pipe into a horizontal hole consisting of a cylindrical protective cap formed with a mating engagement edge, and a horizontal hole.

The above-mentioned jig is used by first fitting an insert into the tip of a resin tube, then covering the insert with a protective cap, and screwing the male thread on the traction tool side into the female thread.

・Example Figure 1 shows a cross section of a retracting jig according to the present invention and an example of its use. ~ side
An insert in which the outer diameter of L' is set slightly larger than the inner diameter of the resin tube, a step 4 consisting of a large diameter part 2 and a small diameter part 3 is provided on the outer peripheral surface, and a female thread 5 is cut in the center of the tip side. , 6 is a cylindrical protective cap whose inner diameter is slightly larger than the outer diameter of the target resin pipe, and which has an engaging edge 7 formed on the distal end side to engage with the insert. In the figure, 8 indicates the target resin pipe, 9 indicates the joint on the pulling side, and 10 indicates the male thread.

The embodiment has the above-mentioned configuration. First, the insert 1 is inserted into the resin pipe 8 until it stops at the stopper 1a, and then the protective cap 6 is placed over it, and the male thread 10 of the joint 9 on the traction side is inserted into the insert 1.
The joint 9 and the insert 1 are connected by screwing into the female screw 5 of the insert 1, and the resin pipe 8 is drawn into the horizontal hole while retracting the auger.

・Effects of the present invention As described above, the present invention involves inserting an insert with a step consisting of a large-diameter part and a small-diameter part into the tip of a resin tube, covering it with a protective tube, and drawing it into a horizontal hole. You can expect similar effects.

a) The insert has a step consisting of a large diameter part and a small diameter part, which increases the frictional force in the large diameter part to connect the insert and the resin pipe, and prevents the outer diameter of the resin pipe from increasing in the small diameter part. Therefore, the outer diameter of the resin pipe does not change at the joining portion, and therefore, no problem occurs when joining the resin pipe to a branch member such as a service cable.

b A protective cap is placed over the tip of the resin pipe to protect it when it is being drawn in, so there is no need to worry about damaging the outer circumferential surface of the joint of the resin pipe during the process of drawing it in, making it easier to carry the resin pipe to the service center. The airtightness will not deteriorate when joined to a branch member such as.

[Brief explanation of the drawing]

FIG. 1 is a sectional view of a jig according to the present invention attached to a resin pipe, FIG. 2 is an exploded perspective view of the jig, and FIG. 3 is an explanatory diagram of a cable grip. DESCRIPTION OF SYMBOLS 1...insert, 2...large diameter part, 3...small diameter part, 4...step, 5...female thread, 6...protective cap, 7...engaging edge, 8...resin pipe, 9... ...Joint, 10...Male thread.

Claims (1)

[Claim for Utility Model Registration] The outer diameter of the tip side is set to be approximately the same as the inner diameter of the resin tube, and the outer diameter of the rear end side is set slightly larger than the inner diameter of the resin tube, so that a large diameter part is formed on the outer peripheral surface. The insert has a step formed by a small diameter part and has a female thread cut in the center of the distal end, and the insert has an inner diameter slightly larger than the outer diameter of the resin tube and has an engaging edge on the distal end that engages with the insert. A cylindrical protective cap consisting of , and a jig for drawing a resin pipe into a horizontal hole consisting of .