JPH07290444A - Diamond core bit - Google Patents

Abstract

(57) [Summary] [Object] The present invention relates to a diamond core bit, and when a dry drilling work is performed on a material such as concrete, the cutting dust is automatically discharged and the diamond core bit tip is It is to suppress the temperature rise of the chip. [Structure] In a diamond core bit comprising a shank 2 having a joint 1 and a tip 3 on the tip circumferential portion, a fanned air hole 4 is provided on the side surface of the shank 2, or a fan 6 is arranged in the shank 2. There is.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a dry type diamond core bit capable of forming a large diameter hole in a material such as concrete without using water.

[0002]

2. Description of the Related Art FIG. 3 shows a diamond core bit according to the prior art. A conventional diamond core bit is composed of a joint 1 and a shank 2 which are held in a chuck of a rotary drive machine such as an electric motor (hereinafter referred to as a drill),
The shank 2 has a tip-shaped tip 3 made of a metal sintered product containing diamond abrasive grains on the tip circumferential portion.

[0003]

As shown in FIG. 4, in the conventional diamond core bit, cutting dust generated during drilling remains, and the cutting dust is present between the side surface of the shank 2 and the concrete cutting side surface, or between the tip 3 and the concrete. Enter between the cutting surface. As the amount of cutting dust between the side surface of the shank 2 and the concrete cutting side surface increases as the drilling progresses, the load resistance against the rotation of the diamond core bit increases, and the cutting speed extremely decreases. At the end, the diamond core bit and the concrete are intermeshed and cannot rotate. Further, when the amount of cutting dust around the tip 3 increases, the tip 3 does not hit the concrete surface, so that the cutting speed is extremely reduced, and finally drilling becomes impossible. As a countermeasure against this, as shown in FIG. 5, there is a method in which a dust collecting adapter 5 is installed around the diamond core bit being drilled, and a dust collector (not shown) sucks cutting dust to perform the work. However, in this method, firstly, the dust collector must be carried around at all times, so that workability is poor. Second, the dust collection adapter cannot be used when there are obstacles or the like near the corners and perforations. There is such a problem. Thirdly, if the depth of drilling becomes deeper, the cutting dust around the tip 3 cannot be completely sucked in, and the work efficiency also decreases.
It's not a perfect measure. Fourthly, the dry diamond core bit is said to cause the temperature of the tip 3 to remarkably rise as compared with the wet diamond core bit using water, which is the cause of shortening the life. The problem remains.

The object of the present invention is to perform a drilling operation with a dry diamond core bit, which enables efficient work without using a dust collector, and more reliably discharges cutting dust when a dust collector is used. By doing so, it is to greatly improve the work efficiency. Moreover,
At the same time, the temperature rise of the tip 3 is suppressed and the life of the diamond core bit is improved.

[0005]

The above-mentioned object is to achieve the shank 2
Shank 2 to force the flow of air inside
This is achieved by providing a vane-shaped air hole 4 on the side surface of the fan, or by disposing a fan 6 in the shank 2.

[0006]

The bladed air holes 4 provided on the side surface of the shank 2 configured as described above and the fan 6 disposed in the shank 2 rotate the diamond core bit,
Forced air suction into shank 2 or shank 2
The air inside is forced out. Therefore, during the drilling operation, the cutting dust accumulated in the shank 2 and the cutting dust around the tip 3 are automatically discharged, and at the same time, the tip 3 is cooled.

[0007]

FIG. 1 and FIG. 2 show an embodiment according to the present invention. FIG. 1 shows an embodiment of claim 1 in which a vane-like air hole 4 is provided on a side surface of a shank 2 of a conventional diamond core bit, and FIG. 2 shows a fan 6 arranged in the shank 2 of a conventional diamond core bit. It is an example of. An example of work when the diamond core bit according to the embodiment is used will be described with reference to FIG. In this embodiment,
Vane holes are provided on the side of the shank 2. When a boring operation is performed with this diamond core bit, air is forcibly sucked into the shank 2 due to the effect of the blades of the air holes during rotation. The sucked air travels toward the tip 3 along the inner side surface of the shank 2 while carrying cutting dust. Further, the air also carries the cutting dust around the tip 3 and travels along the side surface on the outer side of the shank 2 so that the cutting dust can be discharged to the outside. Furthermore, the chip 3 can be cooled by this series of air flows. In the case of the present embodiment, it goes without saying that the effect becomes more reliable if the dust collection adapter 5 is used.

[0008]

According to the present invention, bladed air holes 4 are provided on the side surface of the shank 2 or a fan 6 is arranged in the shank 2 so as to forcibly create the flow of air in the shank 2. Therefore, not only the cutting dust in the shank 2 and the peripheral portion of the tip 3 can be discharged, but also the temperature rise of the tip 3 can be suppressed.

[Brief description of drawings]

FIG. 1 is a sectional view showing an embodiment of a diamond core bit according to the present invention.

FIG. 2 is a sectional view showing an embodiment of the diamond core bit according to the present invention.

FIG. 3 is a cross-sectional view of a prior art diamond core bit.

FIG. 4 is a cross-sectional view of a prior art diamond core bit during a boring operation.

FIG. 5 is a perspective view during a punching operation using the dust collecting adapter.

[Explanation of symbols]

Reference numeral 1 is a joint, 2 is a shank, 3 is a tip, 4 is an air hole with blades, and 6 is a fan.

Claims (2)

[Claims] 1. A shank having a cylindrical shape and a projection-shaped tip made of a metal sintered material containing diamond abrasive grains on the circumference of the tip of the shank are opposite to the tip placement surface of the shank. A diamond core bit having a projection-shaped joint on the end face side so that it can be fixed to a rotary drive such as an electric motor, wherein the side surface of the shank is provided with air holes with blades. 2. A diamond core bit, wherein a fan is arranged in the shank at the same time when air holes are provided on the side surface of the shank.