JPH01122413A - Breaking blade of excavator - Google Patents

Abstract

PURPOSE:To enable the title blade to break a pipe simply with small force, by a method wherein a widening blade forming a V-shaped state narrower than a width of a cutter blade is provided on a position of a cone where the cutter blade meets at right angles with the cone. CONSTITUTION:The tip part of a breaking blade is inserted into a vinyl chloride pipe 7 and the vinyl chloride pipe 7 is deformed into an oval with a cutter blade 3 according as an excavator moves forward. A cutting-off line is formed further on the inside of a vinyl chloride pipe 7 with connecting protrusion 5 provided on the both edges 3a of the blade. When the excavator is moved forward further, after the vinyl chloride pipe 7 has been extended up to the limit, the same is cut off into two with the edge 3a of the cutter blade 3. A cut off vinyl chloride pipe 7' is deformed after a windening blade 6 and core 1 with them. At the time of breaking of the above-mentioned vinyl chloride pipe, which is spread larger than the diameter in a conventional one, while the pipe 7' is being deformed, a connecting protrusion 5 is connected with the beginning end part of cutting-off, therefore, it does not happen that the excavator receives force where the excavator is moved backward through restoring force of the vinyl chloride pipe.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a breaking blade for an excavator that breaks old pipes such as water pipes buried underground without excavation.

[Prior Art] Conventionally, as the breaking blade of the above-mentioned excavator, for example,
- As described in Publication No. 27873, a conical body attached to the tip of the casing of an excavator has a plurality of blades of the same width planted along its generatrix, or a hydraulic or electric motor is used from inside the conical body. A device is known in which a plurality of blades along the generatrix are provided so as to be freely extrudable to the outside.

[Problems to be Solved by the Invention] However, although asbestos pipes and ductile pipes can be broken relatively easily with the breaking blade of the conventional excavator, vinyl chloride pipes are not flexible and ductile. Because of this, there is a problem that once it begins to stretch, it takes too much time to break, and a force that moves the excavator backwards acts, making it necessary to increase the propulsion force.

Therefore, the present invention aims to provide a breaking blade for an excavator that can easily break not only asbestos pipes but also vinyl chloride pipes with a small force.

[Means for Solving the Problems] In order to solve the above-mentioned problems, the present invention provides a breaking blade for an excavator that breaks and expands a dilapidated pipe buried underground. A cone whose base is larger than the inner diameter of the old pipe, and a 7-shaped cut that extends further from the top of the cone and is implanted in the cone along its diametrically opposing generatrix. blade and
The cutting blade has locking protrusions on both cutting edges that are approximately the same width as half the circumference of the aged pipe, and a cone that is planted along the opposing generatrix at a position perpendicular to the cutting blade, and has a width smaller than the cutting blade. It consists of an expanding blade that has a shape.

[Function] According to the above means, the vinyl chloride pipe is stretched in the diametrical direction by the cutting blade and cut into two pieces, and then the expanding blade and the conical body push the pipe wider than the conventional diameter, and the pipe is locked. The protrusion is locked to the cutting start end, and the excavator is not subjected to the force of retreating due to the restoring force of the PVC pipe.

Further, after the asbestos pipe or the like is broken or cut into two pieces in the diametrical direction by the cutting blade, it is further broken into smaller pieces by the expanding blade and the conical body, and is expanded to a larger diameter than the conventional pipe.

[Example] Hereinafter, an example of the present invention will be described with reference to FIGS. 1 to 4.

In the figure, 1 is a cone attached to the tip of the casing 2 of the excavator, and its base has a diameter that is approximately the same as the outer diameter of the casing 2 and is larger than the inner diameter of the old pipe buried underground. The outer diameter of the new pipe to be replaced with the old pipe is the same as that of the new pipe), and inside the casing 2, a supply of compressed air is provided to move the piston forward impulsively, and also to move the piston forward with compressed air. A propulsion machine (not shown) that moves the excavator forward intermittently by slowly moving it backward is housed.

On the outside of the cone 1, a relatively wide, figure-7-shaped cutting blade 3 is implanted along its diametrically opposed generatrix lines. The tip of the cutting blade 3 extends further from the top of the cone 1, and this tip has a wire locking hole 4 for locking a wire lobe of an electric winch that moves the excavator forward together with the propulsion machine. It is provided. Furthermore, locking protrusions 5 are provided on both cutting edges 3a of the cutting blade 3, which have approximately the same width as the half circumference of the aged pipe. As will be described later, the locking protrusion 5 is locked to the cutting start end of the old pipe cut by the cutting blade 3, and prevents the excavator from receiving a backward force due to the restoring force of the old pipe.

Further, on the outside of the conical body 1, an expanding blade 6 having a shape of 7, which is narrower than the cutting blade 3, is installed along the opposing generatrix at a position perpendicular to the cutting blade 3. The expansion blade 6 is used to expand an old pipe made of vinyl chloride or the like which has been cut together with the cone 1 to a diameter larger than that of a conventional pipe.

Next, the action of breaking an old pipe made of vinyl chloride by the breaking blade having the above structure will be explained using FIGS. 5a"-e.

The tip of the Ishitomo cutting blade is inserted into the PVC pipe 7 (the fifth
(See Figure C), as the excavator moves forward, the PVC pipe 7
is deformed into an elliptical shape by the cutting blade 3 (see Fig. 5), and then a cutting line is made inside the PVC pipe 7 by the locking protrusions 5 provided on both cutting edges 3a of the cutting blade 3 (see Fig. 5). (See Figure 5C). As the excavator moves further forward, the vinyl chloride pipe 7 is stretched to the limit and then cut into two by the cutting edge 3a of the cutting blade 3 (see Fig. 5C), and this cut vinyl chloride pipe 7' is As the machine moves forward, the expanding blade 6 and the cone 1 deform the shape into a shape that follows these shapes, and the diameter is expanded to be larger than the conventional diameter (see FIG. 5C).

When the vinyl chloride pipe is broken, the locking protrusion 5 is locked to the cutting start end, so that the excavator is not subjected to a force that causes the excavator to retreat due to the restoring force of the vinyl chloride pipe.

In addition, a new vinyl chloride pipe, ductile pipe, etc. is inserted into the cut and expanded vinyl chloride pipe 7'.
It is something.

Further, after the asbestos pipe or the like is broken or cut into two in the diametrical direction by the cutting blade 3, it is further broken into smaller pieces by the expanding blade 6 and the conical body, and is expanded to a larger diameter than the conventional pipe.

[Effects of the Invention] As described above, according to the present invention, not only asbestos pipes but also vinyl chloride pipes are stretched in the diametrical direction by the cutting blade and cut into two parts, and then the expanding blade and the The diameter of the cutting blade is pushed wider by the cone, and the locking protrusion is locked to the cutting start end, so the excavator is not subjected to the force of retreating due to the restoring force of the PVC pipe, so it is larger than the conventional cutting blade. It can be broken easily and with a small amount of force.

[Brief explanation of the drawing]

1, 2, 3 and 4 are a front view, a top view, a left side view and a right side view of a breaking blade showing one embodiment of the present invention, and FIGS. 5a, b, c, d and e are explanatory views of the action of the breaking blade, respectively.

Claims (1)

[Claims] This is a breaking blade of an excavator that breaks and expands old pipes buried underground.It is attached to the tip of the casing of the excavator, and has a cone whose base is larger than the inside diameter of the old pipe, and a cone with a base larger than the inside diameter of the old pipe. A V-shaped cutting blade is installed along the opposing generatrix in the diametrical direction and extends further from the top of the cone, and a retaining blade is provided on both cutting edges of the cutting blade, which have approximately the same width as half the circumference of the old pipe. A breaking blade for an excavator comprising a stop protrusion and a V-shaped expanding blade that is installed along opposing generatrix lines at a position orthogonal to the cutting blade in a conical body and has a narrower width than the cutting blade.