JPH0647679Y2 - Drilling jig - Google Patents

Description

[Detailed Description of the Invention] [Industrial field of application] The present invention relates to a jig for punching a circular hole in foamed resin,
In particular, it relates to improvement of efficiency of drilling when drilling a long distance in a foamed resin used as a civil engineering material.

[Prior Art] In recent years, by applying Styrofoam to earth structures such as embankments and retaining walls, a Styrofoam civil engineering method that effectively utilizes the characteristics of the material such as lightweight, self-standing when stacked, and water resistance has been developed. Has been adopted.

Also, when burying oil pipes, gas pipes, water pipes, etc. in the ground, a styrofoam block that can support earth pressure is temporarily placed in a groove formed by excavating earth and sand, and then immediately backfilled. , By drilling holes from the side of the backfilled block to form piping holes and drawing the pipes into the piping holes to improve the work efficiency and prevent vertical earth pressure etc. acting on the buried pipe. A civil engineering method for underground pipes has been proposed that can reduce the additional load and prevent damage to the underground pipes (Japanese Patent Application No. 2-88295, Heisei 2).
Application on April 4, 2012).

[Problems to be solved by the invention] When Styrofoam is applied to embankments, retaining walls, etc. as described above, the Styrofoam block may be cut in a straight line, so that processing that corresponds to the local topography can be performed easily. be able to.

However, in order to bury the pipe, it is necessary to make a hole for piping in the styrofoam block buried in the ground. In this case, it is possible to use a cutter, a drill, etc. to make a hole with a short distance in the Styrofoam block, but if you try to make a hole over a long distance using a drill, etc., the resin will soften during processing. Stickiness and rough surface finish. For this reason, it was difficult to form a hole having the same diameter and having a uniform surface in a foam block over a long distance.

The present invention has been made in order to solve such disadvantages, and an object thereof is to obtain a drilling jig capable of drilling holes having the same diameter and having a uniform surface in a foamed resin over a long distance. .

[Means for Solving the Problem] A drilling jig according to the present invention has a steel pipe having a tapered surface on the inner surface of the tip, a conical tip, and a lot connecting portion at the rear end, and a tip portion. Is projected from the tip of the steel pipe and is fixed to the center line of the steel pipe by a support frame, the inner and outer surfaces of the steel pipe, the tip of the center shaft and the heating element fixed to the support frame, and the lot connecting part of the center shaft. And a linked lot to be linked.

[Operation] In the present invention, the center shaft and the steel pipe are inserted into the foamed resin while the foamed resin is melted by the heat generated by the heating elements fixed to the inner and outer surfaces of the steel pipe and the tip of the center shaft, and the circular shape is applied to the foamed resin. Make a hole in.

Further, when the center shaft and the steel pipe are inserted into the foamed resin, the foamed resin is melted by the heating element fixed to the support frame, so that the pushing resistance force by the support frame is reduced.

After the steel pipe has entered the foamed resin, the connected lots are connected to the lot connecting portion of the center shaft to sequentially extend the holes of the foamed resin.

[Embodiment] FIGS. 1 and 2 show an embodiment of the present invention. FIG. 1 is a front sectional view and FIG. 2 is a side view. As shown in the figure,
The drilling jig 1 is a steel pipe 2 having a tapered surface 3 on the inner surface of the tip.
And a center shaft fixed by a support frame 5 on the center line of the steel pipe 2.
It is composed of a linear heating element 6 and a connected lot 7.

The center shaft 4 has a conical front end 8 and a hollow connecting lot 7 at the rear end as shown in the partial sectional view of FIG.
There is provided a lot connecting section 9 for connecting the. Further, a wiring hole 11 through which the electric wire 10 is passed is provided inside the center shaft 4.

As shown in the partial cross-sectional view of FIG. 4, the support frame 5 has a tapered surface 12 at its tip and is fixed so that the tip 8 of the center shaft 4 projects from the tip of the steel pipe 2.

Further, the linear heating element 6 is wound around the inner and outer surfaces of the steel pipe 1 and the portion of the center shaft 4 in front of the support frame 5, and the linear heating element 6 is also stretched at the tip of the tapered surface 12 of the support frame 5. There is. The linear heating element 6 is connected to a power source (not shown) by a wiring hole 11 of the center shaft 4 and an electric wire 10 passing through the hollow portion of the connecting lot 7.

Next, for example, as shown in the cross-sectional view of FIG. 5, an operation when a hole for burying a pipe is drilled by using a hole-piercing jig 1 in a block 21 made of a foamed polystyrene molded product buried in the ground 20. Will be explained. In FIG. 5, 22 is an asphalt concrete, and 23 is a floor slab placed to prevent the block 21 from slipping and preventing it from rising when the block 21 is installed.

First, insert the hole making jig 1 without the connecting lot 7 into the groove for piping / joining provided in the buried portion of the block 21, and make a hole in the block 21 at the conical tip 8 of the center shaft 4. Position the desired position. Then, the punching jig 1 is pressed against the block 21 while applying a current to the linear heating element 6. Since the portion of the block 21 pressed by the drilling jig 1 is melted by the heat of the linear heating element 6, the drilling jig 1
The center shaft 4 and the steel pipe 2 are inserted into the block 21. At this time, since the tip of the steel pipe 2 is formed by the tapered surface 3 and the tip 8 of the center shaft 4 has a conical shape, the drilling jig 1 can be easily inserted into the block 21. As the hole making jig 1 is inserted into the block 21, the support frame 5 hits the block 21, but the linear heating element 6 stretched at the tip of the support frame 5 melts the contact part of the block 21. Since the tapered surface 12 is inserted into this melted portion, the pushing resistance by the support frame 5 can be reduced.

In this way, while the block 21 is being melted by the linear heating element 6, the punching jig 1 is inserted into the block 21, the steel pipe 2 completely enters the block 21, and the block 21 at the rear end of the center shaft 4 is inserted. When the protruding length becomes shorter, the connected lot 7 is attached to the lot connecting portion 9 of the center shaft 4, and the linear heating element 6 is subsequently used to melt the block 21 and punch the jig 1.
Is inserted into the block 21 to extend the hole for embedding the pipe. After that, by sequentially connecting the connected lots 7, holes for burying a pipe having a predetermined long distance can be formed in the block 21.

The block pieces remaining in the holes formed in the block 21 may be removed from the rear end of the hole forming jig 1 or may be extruded and discharged after the hole formation is completed.

[Advantage of the Invention] As described above, the present invention inserts the center shaft and the steel pipe into the foamed resin while melting the foamed resin by the heat generated by the heating elements fixed to the inner and outer surfaces of the steel pipe and the tip of the center shaft. Since the circular holes are formed in the foamed resin, holes having the same diameter and a uniform surface can be formed in the foamed resin.

Also, since the tip of the center shaft is formed in a conical shape and the steel pipe and the tip of the support frame are provided with tapered surfaces, it is possible to insert the drilling jig with a small resistance when inserting it into the foamed resin. it can.

Furthermore, after the steel pipe has entered the foamed resin, the lots of foamed resin can be sequentially extended by sequentially connecting the connected lots to the lot connecting part of the center shaft, so that a circular hole with a long distance can be made into the foamed resin. Can be formed within.

BRIEF DESCRIPTION OF THE DRAWINGS FIGS. 1 and 2 show an embodiment of the present invention, FIG. 1 is a front sectional view, FIG. 2 is a side view, and FIG. 3 is a partial sectional view showing a center shaft, FIG. 4 is a partial cross-sectional view showing the support frame, and FIG. 5 is a cross-sectional view showing an embedded styrofoam block. 1 ... Drilling jig, 2 ... Steel pipe, 4 ... Center shaft, 6 ...
... Linear heating element, 7 ... Connected lot, 9 ... Lot connecting part, 9 ... Electric wire.

Claims (1)

[Scope of utility model registration request] Claim: What is claimed is: 1. A steel pipe having a tapered inner surface at the tip, a conical tip, a lot connecting portion at the rear end, the tip protruding from the tip of the steel pipe, and a supporting frame on the center line of the steel pipe. A fixed center shaft, a heating element fixed to the inner and outer surfaces of the steel pipe, the tip of the center shaft and a support frame, and a connected lot connected to the lot connecting part of the center shaft. A jig for drilling.