JP2002144182A - Tool holder - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a tool holder allowing stable cutting with little deflection through firm two-face restraint by a spindle of a cutting machine. SOLUTION: A clearance g formed between the front face of the spindle S and the back face of a flange 7 of an arbor is filled with a spacer 8 to restrain two faces of the arbor 1 by the spindle S at end point of drawing a taper shank 3 into a taper hole of the spindle S.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a tool holder having an improved holding stability by a spindle of a processing machine.

[0002]

2. Description of the Related Art A tool holder of a type in which a taper tool shank integrated with a main body is drawn into a tapered hole of a main shaft of a processing machine is provided with a rear surface of a flange provided at a root end of the taper tool shank at a drawing end point and a front surface of a main shaft. There is a gap between them. Therefore, the holder is restricted only by the taper fitting portion by the spindle, and the rigidity of supporting the holder is insufficient, so that it is difficult to meet the demand for high precision machining.

Therefore, a tool holder of a two-surface restraint type in which either the tapered surface of the shank or the rear surface of the flange is movable, and the rear surface of the flange is also in close contact with the front surface of the spindle at the position where the tapered shank is in close contact with the tapered hole. Have been devised and put to practical use.

[0004]

The two-surface restraint type tool holder presses the movable-side constrained surface with a spring. However, since the force of the spring that can be incorporated in the holder is limited, a strong two-sided tool holder is required. Can not expect surface constraint. Recently, it has been required to further increase the support rigidity of the holder and the support rigidity of the cutting tool by the holder in order to perform processing with higher precision, and such demands cannot be met.

[0005] Therefore, an object of the present invention is to provide a tool holder capable of obtaining a supporting rigidity that is superior to that of a two-surface restraint type tool holder.

[0006]

In order to solve the above-mentioned problems, according to the present invention, a taper tool shank integrated with a main body is drawn into a taper hole of a main shaft of a processing machine, and is inserted into a tool holder which is attached to the main shaft. Thus, a spacer is provided to fill a gap formed between the rear surface of the flange of the taper tool shank and the front surface of the spindle.

A tool holder for holding a tool by pulling a taper shank of a cutting tool into a taper hole at a tip of a main body, and pulling a taper tool shank integral with the main body into a taper hole of a main shaft of a processing machine to be attached to a main shaft. A gap formed between the front surface of the main body of the holder and the back surface of the main body of the cutting tool at the retraction end point of the taper shank, and the rear surface of the flange of the taper tool shank and the front surface of the spindle at the retraction end point of the taper tool shank. That is, two spacers are provided to fill gaps generated between the two.

[0008]

According to the tool holder of the present invention, the gap formed between the front surface of the spindle and the rear surface of the flange at the end point of the retraction of the taper tool shank is filled with the spacer, so that not only the tapered surface of the shank but also the rear surface of the flange is formed. It is firmly restrained via the spacer.

When the taper shank of the cutting tool is drawn into the tapered hole of the main body of the holder, the gap formed between the front surface of the main body of the holder and the back surface of the main body of the tool is filled with the spacer. Is firmly formed on the two surfaces, thereby preventing runout of the holder and the tool and improving the machining accuracy by the cutting tool.

FIG. 1 shows an embodiment of a tool holder according to the present invention. The figure shows an arbor with a tapered shank for a face cutter. The arbor 1 is formed by integrally providing a tapered tool shank 3 behind a cylindrical main body 2.

A boss 4 for centering which is inserted into the center hole of the face cutter A, and a key 5 for transmitting torque which is fitted into a key groove on the back of the cutter A are provided at the tip of the main body 2. A pull stud 6 is attached to the rear of the tapered tool shank 3. The pulling of the taper tool shank 3 into the main shaft S of the processing machine may be performed using a pull bolt.

The taper tool shank 3 includes a flange 7, and a spacer 8 is attached to the back surface of the flange 7 by screwing. The spacer 8 has a thickness that exactly fills a gap g generated between the main shaft S and the flange 7 at the end point of retraction of the shank 3.

When the shank 3 is pulled in strongly, the metal spacer is also elastically deformed, albeit in a small amount. Therefore, the thickness of the spacer 8 may be set in consideration of the thickness reduction due to the elastic deformation.

FIG. 2 shows a tool holder (a boring bar in the figure) of the second embodiment. This boring bar 10 is provided with an integrated taper tool shank 13 behind a main body 12 having a tapered hole 11, and a spacer 8 for filling a gap g between the main shaft S and the rear surface of a flange 14 at the tip of the shank is screwed. Mounted.

A spacer 15 is also attached to the front surface of the main body 2. Reference numeral 20 in the figure denotes a cutting tool having an integral taper shank 22 behind the main body 21. A throw-away tip 23 is attached to the tip of the main body of the tool.

The illustrated cutting tool 20 includes a boring bar 1.
Taper shank 22 with pull bolt 16 passing through the axis of
Is drawn into the tapered hole 11. At the end point of the retraction, a gap g1 is generated between the back surface of the tool body 21 and the front surface of the boring bar body 12. Spacer 15
Has a thickness that fills the gap g1. Therefore, the boring bar 10 is constrained by the spindle S and the cutting tool 20 is constrained by the boring bar 10 on both surfaces, and machining with less runout can be performed.

In the illustrated tool holders, the tapered surface of the shank and the inner surface of the tapered hole are worn due to repeated use, and the gaps g and g1 gradually decrease. It can respond by adjusting the thickness.

The adjustment of the spacer thickness can be performed by polishing or the like, and is not particularly difficult.

[0019]

As described above, the tool holder of the present invention fills the gap generated between the spindle of the processing machine and the flange of the holder at the end point of drawing in the taper tool shank with the spacer whose thickness has been adjusted. Therefore, the two surfaces of the holder are firmly restrained, the support rigidity of the holder is remarkably increased, and high-precision processing with little runout can be performed.

In the cutting tool having a tapered shank which is drawn into the tapered hole of the main body of the holder, a gap formed between the main body of the holder and the main body of the tool is filled with the spacer. Both the supports are stable, and the processing stability is further improved.

[Brief description of the drawings]

FIG. 1 is a side view showing an embodiment of a tool holder according to the present invention.

FIG. 2 is a partially broken side view of another embodiment.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Arbor 2, 12 Body part 3, 13 Taper tool shank 7, 14 Flange 8, 15 Spacer 10 Boring bar 11 Taper hole 20 Cutting tool 21 Body part 22 Taper shank S Main shaft g, g1 Gap

Claims (2)

[Claims] In a tool holder, a taper tool shank integrated with a main body is drawn into a tapered hole of a main shaft of a processing machine and attached to the main shaft. The tool holder is formed between a rear surface of a flange of the taper tool shank and a front surface of the main shaft at a drawing end point. A tool holder comprising a spacer for filling a gap. 2. A tool holder for pulling a taper shank of a cutting tool into a tapered hole at a tip end of a main body portion to hold the tool, and pulling a taper tool shank integral with the main body portion into a tapered hole of a main shaft of a processing machine and attaching the tool to the main shaft. In the gap between the front of the body of the holder and the back of the body of the cutting tool at the retraction end point of the taper shank, the back of the flange of the taper tool shank and the front of the spindle at the retraction end point of the taper tool shank. A tool holder comprising two spacers each of which fills a gap generated between the tool holders.