JPS6339048Y2 - - Google Patents

Description

[Detailed Description of the Invention] [Industrial Field of Application] The present invention relates to a drill for drilling large-diameter holes in concrete such as concrete plates, particularly lightweight foamed concrete plates.

[Conventional technology]

Conventionally, this type of drill has a cylindrical (cap-shaped) shape with a large number of cutting teeth A, A arranged on one end edge, as shown in Fig. 3.
It is known that a hole having a large diameter corresponding to the diameter of the main body B is bored while a center drill C is mounted on the center line of the main body B and positioned.

[Problem that the invention attempts to solve]

The conventional drill as shown in FIG. 3 has a disadvantage in that a part of the workpiece drilled inside the main body B becomes a doughnut-shaped lump that is difficult to remove.

In view of these points, the present invention has been devised to prevent the object to be cut from forming a lump and clogging the inside of the main body.

[Means for solving problems]

The present invention has a cylindrical main body 1 in which a large number of cutting teeth 2, 2 are arranged on one end edge, and a center awl 3 is mounted on the center line, from the center where the center awl is located to the peripheral edge where the cutting teeth are located. A wing-shaped rake blade 4 is disposed toward the.

[Effect]

When the tip of the center awl 3 is placed in the center of the hole and rotated, the large diameter is A hole is drilled.

At this time, the object to be cut located inside the cylindrical main body 1 is cut into small pieces by the rake blade 4, and large lumps do not get stuck inside the cylindrical main body 1.
Unlike conventional products whose main body is cap-shaped and which limits the depth of one drilling, drilling progresses without any limitation on the depth of drilling.

〔Example〕

Embodiments of the present invention will be described based on the accompanying drawings.

On the lower edge of the cylindrical main body 1, a large number of cutting teeth 2, 2, which are slightly serrated like saw teeth, are arranged in a row. A rake blade 4 is fixed inside the cylindrical main body in close proximity to the cutting teeth 2.

In order to fix the rake blade 4 inside the cylindrical main body 1, it is preferable to weld or screw the tip of the wing-shaped rake blade to the inner surface of the cylindrical main body.

That is, the rake blade 4 is made to protrude radially (in three directions in the drawing) from the boss 5 through which the center awl 3 can pass,
The tip is welded or screwed to the inner surface of the cylindrical main body 1.

A set bolt 6 is provided on the boss 5 so that the center cone 3 and the cylindrical main body 1 can be fixed at a desired position.

In the drawing, 7 is for tightening the set bolt 6.
This is a hole drilled in the cylindrical main body 1 so that a wrench can be inserted.

Note that the number of rake blades 4 may be plural as in the illustrated example, or may be only one.

Moreover, although the cylindrical main body 1 is illustrated as a so-called cylinder, it is of course possible to have a cap shape as shown in FIG. 3, and to provide a rake blade inside thereof.

The total length L of the cylindrical main body 1 is arbitrarily selected depending on the application. In other words, when drilling a deep hole, the overall length L is lengthened so that the hole can be drilled straight using the cylindrical main body 1 itself as a guide. Even if the cone protrudes, a portion that serves as a guide at the rear of the cone remains and the cone does not completely penetrate, making it easy to remove the cone from the object to be drilled.

[Effect of idea]

According to the concrete drill of the present invention, since the material to be cut inside the cylindrical main body, which is the chips during drilling, is finely cut, there is no drawback that the material becomes lumps and gets clogged inside, unlike the conventional method.

In particular, in areas where core materials such as reinforcing bars are inserted into the concrete plate, conventional cutting would result in a tough donut-shaped lump that would become stuck inside the cylindrical main body, but with this invention, the first step is to scoop it out. Since the concrete part is cut away by the blade, the concrete and core material can be easily separated and removed as separate parts very easily.

[Brief explanation of drawings]

Figures 1 and 2 of the accompanying drawings show an embodiment of the concrete cone of the present invention, in which Figure 1 is a longitudinal sectional view, Figure 2 is a bottom view, and Figure 3 is a longitudinal sectional view of a conventional product. It is. 1... Cylindrical main body, 2... Cutting teeth, 3... Center drill, 4... Rake blade.

Claims (1)

[Scope of utility model registration request] In a large-diameter aperture in which a center aperture 3 is mounted on the center line of a cylindrical main body 1 with a large number of cutting teeth 2, 2 arranged on one end edge, the inside of the cylindrical main body 3 contains a material to be cut. A concrete awl characterized in that a wing-shaped rake blade 4 is disposed from the center where the center awl 3 is located to the peripheral edge where the cutting teeth 2 are located for cutting.