JPS5917537Y2 - Hole saw cutter - Google Patents

Description

[Detailed description of the invention] This invention relates to a hole saw cutter for drilling round holes in iron plates.

Larger than normal drill diameter, e.g. 25 mmφ
When drilling a round hole with a diameter of ~100 mmφ or more in a steel plate, conventionally, as shown in FIG. At the lower circumferential edge of the boring head 1, there is a blade 3 shaped like an endless band saw.
A hole saw cutter is used.

After this hole cutter is connected to a portable electric motor using a chuck, a hole is first drilled at the center of the hole using the drill 2, and the blade 3 is
This method cuts the iron plate into rounds, but this structure has the following drawbacks and is extremely inconvenient.

That is, one drawback is that after drilling, the round part of the iron plate that remains at the center will fit into the cup-shaped boring head 1, and this stuck piece must be removed in order to make the next drilling possible. However, this is extremely difficult and difficult to overcome.

In particular, the thicker the iron plate, the stronger this tendency is.

The second drawback is that even if the blade 3 is nicked, it is difficult to remove chips, and as a result, the cutting edge wears out quickly and becomes unable to cut quickly, forcing the entire blade to be discarded.

The third drawback is that the thickness of the steel plate that can be cut is only about 5 mm, and it is impossible to poll anything beyond that thickness.

The purpose of this invention is to provide a hole saw cutter that can remove the above-mentioned debris and chips well and can cut well even when the plate thickness is thick.
The approximate configuration will be explained using the embodiment shown in FIG.
It is as follows.

The hole saw cutter of this invention is also the same as the conventional example shown in FIG. 1 in that a twist drill 11 is protruded relatively long from the center of the boring head 10, but the boring head 10 has a rectangular groove. It differs from the conventional one in that it is disc-shaped with 12 holes formed at equal intervals in the radial direction.

In the illustrated example, the number of square grooves 12 is four, but the number is by no means limited to this example.

A flat plate bit 13 is fitted into each square groove 12, and is integrally mounted with a bold 14 so as to be tangential to the boring head recess 0.

To explain this in detail with reference to FIG. 3, in FIG.
Also, the thick solid line indicates the base circle A and the circle C concentric with this base circle A.
However, the plate bit 1 is placed exactly in the middle of the plate bit 13.
3. The inner surface is tangentially in contact with the base circle A, and at this time, the outer corner B of the plate cutting tool is on a circle C that is larger than the base circle A.

Therefore, if boring is performed using the plate cutting tool 13, the area between the base circle A and the circle C will be cut and removed.
In the end, a round hole corresponding to the circle C is drilled in the iron plate, while the inner part E of the base circle A remains as a remnant.

What should be noted is the area D surrounded by the base circle C and the outer surface of the plate cutting tool 13, which is shown diagonally hatched in the figure, and the area D surrounded by the base circle A and the inner surface of the plate cutting tool 13. The parts D' and D' before and after the cutting become a gap, and during cutting,
This point serves as a passageway for removing chips.

In order to perform the above-mentioned polling with the plate cutting tool 13, several blades 15 as shown in the figure are attached to the lower edge of the plate cutting tool 13.
This can be achieved by providing

That is, the tip of the blade in the rotational direction may be used to cut a portion inside the circle C, and the middle blade may be used to cut a portion outside the base circle A.

In addition, in the figure, 16 is an instance piece.

By appropriately changing the thickness of the distance piece 16, it is possible to change the diameter of the base circle A, in other words, the diameter of the hole to be cut into a circle.

As described above, the hole saw cutter of this invention has a disk-shaped boring head 10 in which square grooves 12 are formed at equal intervals in the radial direction, and a long drilled bore 11 protruding from the center, and several blades 15 on the lower edge. The flat plate cutting tool 13 with a hole formed thereon is inserted into the square groove 12 and attached so as to be in contact with the base circle A. Since it contacts the shaped plate bit 13 in a straight line, it can be removed very easily even when it is attached to the chuck without having to remove it from the chuck each time. If a hole is drilled to this point, the space between the continuously horizontally arranged chevron-shaped cutting edges will be buried in the workpiece, and since both sides of the arc-shaped saw blade are in close contact with the workpiece, there will be no outlet for the chips. In contrast, in this invention, flat plate pie 1~
Therefore, the drilling itself always forms a space I) and D' on both sides of the plate cutting tool, and the chip removal by each month 15 is carried out through the gap on the side. Since it can be carried out from both the angle and D', it is possible to prevent wear on the cutting edge, and because the contact area between the plate bit and the workpiece is small and there is less friction due to clogging, the amount of heat generated is small, and the sharpness of the cutting edge is not deteriorated due to this heat. It is small.

C. The above-mentioned voids and D' can be formed regardless of the height of the cutting edge or the depth of the hole, so it is possible to cut a steel plate with a thickness of about 30 mm, which makes it extremely effective in practical use. It is something.

[Brief explanation of the drawing]

FIG. 1 is a perspective view of a conventional example, FIG. 2 is a perspective view of the main business, and FIG. 3 is a diagram illustrating the principle of forming the gap and D' by the cutter of the present invention. 10...Boring head, 11...
Twist drill, 12... Square groove, 13...
...Plate bite, 15...Blade.

Claims (1)

[Scope of utility model registration request] A twist drill 11 is long protruding from the center of a disc-shaped boring head 10 in which square grooves 12 are formed at equal intervals in the radial direction, and a flat plate-shaped plate bit 13 with several blades 15 formed on the lower edge is attached to the above. It is installed by fitting into the square groove 12, and is located inside the base circle C passing through the outer corner B of the plate cutting tool 13 with the tip 15 of the several blades 15 mentioned above in the direction of rotation. Cut the plate byte 13 using the middle blade 15.
Cut a location outside the base circle A that is in contact with the inner surface of the plate cutting tool 13, thereby cutting a location D surrounded by the base circle C passing through the outer corner B of the plate cutting tool 13 and the outer surface of the plate cutting tool, and the plate cutting tool 13. Anteroposterior location D' formed by the base circle A and the inner surface of the plate cutting tool, which are in contact with
A hole saw cutter characterized in that D' is not used as a passage for removing chips.