JPH11347819A - Drill - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a drill capable of being easily controlled in the fed height, when it is fed to the spindle of a printed circuit board working machine. SOLUTION: In this drill 14 integratedly formed out of a shank part 14a held with a working machine, a tapered head part 14b, and a cutting edge part 14c of smaller diameter than the shank part 14a, it is formed with a shaft part 14d of smaller diameter than the shank part 14a and larger diameter than the cutting edge part 14c and a taper part 14e connecting together between the shaft part 14d and the cutting edge part 14c, between the neck part 14b and the cutting edge part 14c, and the length from the head part 14b up to the extreme end of the cutting edge part 14c is made fixed regardless of the length of the cutting edge part 14c.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a drill for drilling a printed circuit board, for example, and more particularly to a drill suitable for processing a very small hole having a diameter of 0.7 mm or less.

[0002]

2. Description of the Related Art A printed board processing machine, for example, a printed board drilling machine for punching a printed board is shown in FIG.
The configuration is as shown in FIG. In FIG. 1, a table 2 is supported on a bed 1 via a linear guide mechanism (not shown) so as to be movable in the direction of arrow X, and is driven by a screw feed mechanism (not shown). Column 3 is arranged so as to straddle. The table 2 is set with a processing area 2a for mounting a printed circuit board and a tool supply area 2b for arranging a processing drill.

The column 3 is provided with a cross slide 6 movably supported in a direction indicated by an arrow Y via a linear guide mechanism 4 and driven by a screw feed mechanism (not shown) including a motor 5. . This cross slide 6
A pair of saddles 9 movably supported in a direction indicated by an arrow Z via a linear guide mechanism 7 and driven by a screw feed mechanism (not shown) including a motor 8 are arranged. Each saddle 9 is provided with a pair of spindle units 10.

[0004] A drill (not shown) supplied to a predetermined position of the tool supply area 2b of the table 2 is held by a spindle supported by the spindle unit 10, and is positioned and fixed to the processing area 2a of the table 2. X, the drill held on the printed circuit board and spindle
Drilling is performed on the printed circuit board by relatively moving in the Y and Z directions.

[0005] The number of holes formed in a printed circuit board is as large as tens of thousands per printed circuit board. On the other hand, the number of holes that can be drilled by one drill is several thousand, depending on the diameter of the drill. Therefore, it is required to supply a large amount of drills.

Therefore, a magazine for supplying a drill and a tool post for attaching and detaching a drill as shown in FIG. 6 have been proposed. This magazine 11 has, for example, 50
Drill holders 12 are formed, and are detachably supported on the base 13. A drill 14 is detachably held in each of the drill holding units 12. Magazine 11
A pair of tool posts 1 for attaching and detaching a drill, comprising a collar 15b and a holder 15c urged by a spring 15a, and a sleeve 15d for supporting them slidably.
5 is provided to transfer the drill 14 to and from the spindle.

In such a printed circuit board drilling machine, when drilling a printed circuit board, in order to improve the life of the drill, the processing speed, etc., the amount of cut of the drill into the printed circuit board is set to the minimum necessary. It is necessary to.

In order to control the amount of cutting of the drill into the printed circuit board, if the amount of movement of the spindle of the printed circuit board machine in the Z direction is constant, the amount of projection of the drill held by the spindle from the tip of the spindle is made constant. It is necessary to keep. For this reason, a metal or synthetic resin collar is mounted at a fixed position from the cutting edge of the shank of the drill, and the supply height of the drill is controlled by the collar.

[0009]

The diameter of a hole to be processed in a printed circuit board is reduced in accordance with the increase in the mounting density of the printed circuit board. I have. When machining such a very small diameter hole, for example, as the number of rotations required for the drill, for example,
High speed rotation of about 200 Krpm is required.

In order to realize such high-speed rotation, the diameter of the spindle is reduced and the weight of the printed board processing machine is reduced. For this reason, when a collar is attached to a shank portion of a drill as in the related art, if the collar has minute eccentricity due to processing accuracy or the like, the main shaft or the drill oscillates and cannot be processed.

For this reason, without using a collar, as shown in FIG. 7, the tapered surface of the neck 14b of the drill 14 is brought into contact with the shoulder 12a in the drill holding portion 12 to control the supply height of the drill 14. There must be.

Generally, the relationship between the diameter D and the length L of the cutting edge portion 14c of the drill is L = 8 to 17D. For example, as shown in FIG. 8A, the diameter of the shank portion 14a is 2.0 mm, and the taper angle of the neck portion 14b is 30 °.
The diameter of the cutting blade portion 14c is 1.0 mm and the total length is 31.7.
In the case of a 5 mm drill, the length of the neck is 1.87 mm, and if the length of the cutting edge 14c is 8.2 mm, the neck 1
The total length of 4b and the cutting edge portion 14c is 10.07 mm. At this time, the length of the shank portion 14a is 21.68 m
m.

As shown in FIG. 1B, the shank portion 14a has a diameter of 2.0 mm, the neck portion 14b has a taper angle of 30 ° and the cutting edge portion 14c has a diameter of 0.3 mm.
In the case of a drill having a total length of 31.75 mm, the length of the neck is 3.17 mm, and if the length of the cutting edge 14c is 5 mm, the total length of the neck 14b and the cutting edge 14c is 7.17.
mm. At this time, the length of the shank portion 14a is 2
It becomes 3.58 mm.

Further, as shown in FIG. 3C, the diameter of the shank portion 14a is 2.0 mm, the taper angle of the neck portion 14b is 30 °, and the diameter of the cutting edge portion 14c is 0.1 m.
m, the length of the neck is 3.55 mm in the case of a drill having a total length of 31.75 mm, and the length of the cutting edge portion 14c is 1.4 m.
Assuming m, the total length of the neck 14b and the cutting blade 14c is 4.95 mm. At this time, the length of the shank portion 14a is 26.8 mm.

Therefore, as shown in FIG. C, the supply height of the drill 14 is controlled by bringing the tapered surface of the neck portion 14b of the drill 14 into contact with the shoulder portion 12a in the drill holding portion 12, so that the drill is not attached or detached. When the amount of movement of the spindle is constant, when the drill 14 is mounted on the spindle, the amount of protrusion of the drill 14 from the end face of the spindle fluctuates due to the diameter of the cutting edge portion 14c of the drill 14, and proper machining can be performed. become unable.

Further, when setting the amount of projection of the drill by bringing the end face of the shank portion of the drill into contact with the bottom surface of the chuck on the spindle side, an unnecessary impact may be applied to the drill and the drill may be damaged.

In view of the above circumstances, an object of the present invention is to provide a drill capable of easily controlling a supply height.

[0018]

In order to achieve the above object, according to the first aspect of the present invention, a shank portion held by a processing machine, a tapered neck portion, and a smaller diameter than the shank portion are provided. In a drill in which a cutting edge is formed integrally, a shaft portion having a diameter smaller than the shank portion and larger than the cutting edge portion between the neck portion and the cutting edge portion, and between the shaft portion and the cutting edge portion. Was formed, and the length from the neck to the tip of the cutting edge was made constant regardless of the length of the cutting edge.

Further, in the invention according to claim 2,
The invention according to claim 1, wherein the diameter of the shank portion is 1.8 to 3.2 mm, and the taper angle of the neck portion is 20 to 4.
0 ° The cutting edge has a diameter of 0.05 to 0.7 mm, the shaft has a diameter of 1.2 to 1.6 mm, the taper has a taper angle of 10 to 50 °, and a total length of 25 to 40 mm. However, the existing printed circuit board processing machine can be used without any modification.

[0020]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a side view of a drill according to the present invention. In the figure, reference numeral 14 denotes a drill, which is a shank portion 14a, a tapered neck portion 14b, a cutting edge portion 14c smaller in diameter than the shank portion, and a shaft portion smaller in diameter than the shank portion 14a and larger in diameter than the cutting edge portion 14c. 14d and a tapered portion 14e for joining between the shaft portion 14d and the cutting edge portion 14c.
Are formed integrally, and the neck portion 14 is formed regardless of the length of the cutting blade portion 14c.
The length from b to the tip of the cutting edge portion 14c is constant.

The dimensions of each part are the same as those of the shank part 1.
4a has a diameter D1 of 1.8 to 3.2 mm, and the neck 14b
Is 20 to 40 degrees. The diameter D of the cutting edge portion 14c.
2 is 0.05 to 0.7 mm, the diameter D3 of the shaft portion 14d.
Is 1.2 to 1.6 mm, the taper angle β of the tapered portion 14e is 10 to 50 °, and the total length L is 25 to 40 mm.

The diameter D2 and the length L2 of the cutting edge 14c
Is L2 = 8 to 17D2. Also, neck 1
4b, the length L3 of the shaft portion 14d and the tapered portion 14e are
The diameter D of the shaft portion 14d such that L3 = constant length−L2.
Set 3 and its length. Further, the length L1 of the shank portion 14a is L1 = L−L2−L3.

[0023]

FIG. 2 shows a shank 14a having a diameter of 2 mm and a cutting blade 14a.
An example of a drill having a diameter c of 0.3 mm and an overall length L of 31.75 mm is shown.

The dimensions of each part are as follows: the shank part 14a has a diameter of 2 mm and a length of 21.68 mm; the cutting blade part 14c has a diameter of 0.3 mm and a length of 5 mm (L / D2 = 16.7); The diameter of 14d is 1.4 mm, and the taper angles α and β of the neck portion 14b and the tapered portion 14e are each 30 °.
b, the length of the shaft portion 14d and the length of the tapered portion 14e are 5.07
mm.

Embodiment 2 FIG. 3 shows that the shank 14a has a diameter of 2 mm and the cutting blade 14a has a diameter of 2 mm.
An example of a drill having a diameter c of 0.1 mm and an overall length L of 31.75 mm is shown.

The dimensions of each part are as follows: the shank part 14a has a diameter of 2 mm and a length of 21.68 mm; the cutting blade part 14c has a diameter of 0.1 mm and a length of 1.4 mm (L / D2 = 14); The diameter of 14d is 1.4 mm, and the taper angles α and β of the neck portion 14b and the tapered portion 14e are each 30 °.
b, the length of the shaft portion 14d and the length of the tapered portion 14e are 8.67.
mm.

As shown in the above embodiments, the cutting blade 14
The length (L2 + L3) from the neck 14b to the tip of the cutting edge 14c is constant (10.07 mm) even if the diameter of c is different.
Can be set to Therefore, by controlling the supply height of the drill 14 with the tapered surface of the neck 14b,
The protrusion amount of the drill 14 from the spindle when the drill is mounted on the spindle of the printed circuit board processing machine can be controlled to be constant.

As shown in FIG. 4, a tool post for delivering a drill to and from a spindle is formed with a plurality of slits in a holding portion of a sleeve 15d so as to be elastically deformable. A simple configuration in which the holder 15c that generates the holding force is simply fixed can be provided.

[0029]

As described above, according to the present invention, in a drill in which a shank portion held by a processing machine, a tapered neck portion, and a cutting blade portion smaller in diameter than the shank portion are integrally formed, A shaft portion smaller in diameter than the shank portion and larger in diameter than the cutting blade portion between the neck portion and the cutting blade portion, and a tapered portion joining the shaft portion and the cutting blade portion is formed. Because the length from the neck to the tip of the cutting edge is constant regardless of the length,
When supplying a drill to a processing machine, it is possible to easily manage the height of the drill (the length of the drill projecting from the spindle). In particular, it is possible to easily manage the protrusion length of the drill having a very small diameter (for example, 0.3 mm or less), from which the length of the cutting edge portion is reduced, from the spindle. Also,
It is not necessary to bring the chuck on the spindle side into contact with the shank of the drill, so that unnecessary impact is given to the drill and the drill is not damaged.

[Brief description of the drawings]

FIG. 1 is a side view of a drill according to the present invention.

FIG. 2 is a side view of a drill according to the present invention.

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

FIG. 4 is a sectional view of a tool post for holding a drill according to the present invention at the time of drill change.

FIG. 5 is a perspective view of a printed board processing machine.

FIG. 6 is a sectional view of a magazine and a tool post in the printed board processing machine.

FIG. 7 is an enlarged view showing a holding state of a drill in a magazine.

FIG. 8 is a side view showing the shape of a conventional drill.

[Explanation of symbols]

14 drill, 14a shank, 14b neck, 1
4c: cutting edge portion, 14d: large diameter shaft portion, 14e: tapered portion.

Claims (2)

[Claims] 1. A drill having a shank portion held by a processing machine, a tapered neck portion, and a cutting edge portion having a smaller diameter than the shank portion, wherein the shank is located between the neck portion and the cutting edge portion. A shaft portion smaller in diameter than the cutting portion and a taper portion for joining between the shaft portion and the cutting portion, and the tip of the cutting portion from the neck regardless of the length of the cutting portion. A drill characterized by a constant length up to. 2. The diameter of the shank portion is 1.8 to 3.2 m.
m, the taper angle of the neck is 20 to 40 °, the diameter of the cutting edge is 0.05 to 0.7 mm, and the diameter of the shaft is 1.2 to
1.6 mm, the taper angle of the tapered portion is 10 to 50 °,
The drill according to claim 1, wherein the total length is formed to be 25 to 40 mm.