JPH07314231A - Gun drill - Google Patents

Abstract

PURPOSE:To facilitate the chip removing work by reducing the dimension of the chip generated during the work as small as possible by forming a cutter from a plurality of cutting edges having each stage difference. CONSTITUTION:At the top end of a gun drill 3, the second gun drill 4 having a small diameter is formed integrally, and the diameter (d) of the second gun drill 4 is set smaller than the diameter D of the gun drill 3. On the A side between the top end A side and B side of the second gun drill 4, a cutting edge 5 is formed, while, on the A side between the top end A sides and B sides of the gun drill 3, a cutter 6 is formed. The cutter 6 is formed from a plurality of small cutters 6a,... having each stage difference. Working is carried out by the cutters 5 and 6, and in this case, chips are generated. Since the cutting edge 6 is formed from a plurality of small cutters 6a having each stage difference, the dimension of the chip generated during the work can be reduced in correspondence with the small cutting edge 6a.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a gun drill, and more particularly to a gun drill capable of reducing chips.

[0002]

2. Description of the Related Art FIG. 4 shows an example of a gun drill for cutting a work. In the figure, 100 is a gun drill, L is the center line of the gun drill 100, and the tip of the gun drill 100 has a second gun drill 101 of small diameter. Is provided.
A blade is formed on the A side of the tip A of the gun drill 100 and the side B, and C at the tip of the second gun drill 101.
The blade is formed on the C side of the side and the D side.

[0003]

By the way, when a work is cut by such a gun drill, chips are generated from a portion of the gun drill 100 that is cut by the blade A side, but the blade on the A side is relatively long. Therefore, the chips generated are also large. Therefore, when such a large chip is generated, there is a problem that it becomes difficult to remove the chip thereafter.

[0004]

In order to solve the above-mentioned problems, the present invention is a gun drill for forming a cutting edge at a tip and processing a work with this cutting edge, wherein the cutting edge has a plurality of cutting steps. It is characterized by being formed by a blade.

[0005]

Since the cutting blade of the gun drill is formed by a plurality of cutting blades having steps, the chips generated by each cutting blade are small.

[0006]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT A preferred embodiment of the present invention will be described below with reference to the accompanying drawings. FIG. 1 is a plan view of the work W, and FIG. 2 is a sectional view taken along line 2-2 of FIG. 1. In the present embodiment, the work W is a valve body of an automatic device of an automobile. A valve hole 1 is formed in the work W as shown in FIG. 2, and a plurality of oil holes 2 ... Are formed in a direction orthogonal to the valve hole 1.

FIG. 3 is a side view of a gun drill according to the present invention, which is for forming the valve hole 1 of the work W. As shown in FIG. As shown in this figure, a small diameter second gun drill 4 is integrally formed at the tip of the gun drill 3, and the diameter d of the second gun drill 4 is set smaller than the diameter D of the gun drill 3.

The center line of the second gun drill 4 coincides with the center line L of the gun drill 3, and the cutting edge 4a of the second gun drill 4 is deviated from the center line L of the gun drill 3. There is. This deviation amount is ¼ of the diameter d of the second gun drill 4, that is, d / 4.

Of the tip A side and B side of the second gun drill 4, a cutting edge 5 is formed on the A side, and similarly, the tip 6 of the gun drill 3 is attached to the A side of the tip A side and B side. Form. In the present invention, this blade 6 is provided with a plurality of steps (two in the embodiment).
3) small cutting blades 6a. When the valve hole 1 is formed in the work W by the gun drill as described above, the cutting blades 5 and 6 perform processing, and at that time, chips are generated. By the way, in this embodiment, since the cutting blade 6 is composed of a plurality of small cutting blades 6a having steps, the chips generated during processing are small in accordance with the small cutting blade 6a (this). Is clear when compared with the conventional example shown in FIG. 4). Therefore, the work of removing the chips after processing can be facilitated.

[0010]

As described above, according to the present invention, since the cutting blade of the gun drill is formed by a plurality of cutting blades having steps, the cutting dust generated by each cutting blade becomes small, and the cutting dust becomes small. Can be easily removed.

[Brief description of drawings]

[Figure 1] Plan view of work

FIG. 2 is a sectional view taken along line 2-2 of FIG.

FIG. 3 is a side view of the gun drill of the present invention.

FIG. 4 is a side view of a conventional gun drill.

[Explanation of symbols]

 3 ... Gun drill 6 ... Cutting edge 6a ... Small cutting edge

Claims (1)

[Claims] 1. A gun drill having a cutting edge formed at a tip thereof and a workpiece being machined by the cutting edge, wherein the cutting edge is formed by a plurality of cutting edges having steps.