JP2002028807A - Tool holder and unchucking method for it - Google Patents

Abstract

PROBLEM TO BE SOLVED: To reduce the cost of an unchucking system capable of easily unchucking a collet chuck press-fittingly chucked to a holder main body by simple operation. SOLUTION: In this tool holder, a tapered shank part 12A1 of the collet chuck 12 holding a tool 9 is connected to a tapered hole 114 of the holder main body 11 by press-fitting. In the tool holder, a female screw part 131 of an antichucking jig 13 is engaged with a male screw part 12A4 of a flange part 12A3, and with the engaging tip of the unchucking jig 13 abutted on the front end face 113A of the holder main body 11, the unchucking jig 13 and the holder main body 11 are rotated in the direction of screwing the flange part 12A3 into the unchucking jig 13. By this rotation, the engagement side tip of the unchucking jig 14 is pressed to the front end face 113A of the holder main body 11 to pull out the taper shank part 12A of the collet chuck 12 from the tapered hole 114 of the holder main body 11.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention has a holder body having a tapered hole on the inner periphery of a tip end, and a collet chuck for gripping a cutting tool such as a drill. The present invention relates to an unchucking method for detaching a collet chuck coupled to a tool holder and a holder main body which are coupled by press-fitting.

[0002]

2. Description of the Related Art Conventionally, as a tool holder for holding a tool such as a drill having a shank diameter of 2 mm or less, a tool holder having a structure shown in FIG. 4 is known. 4, the tool holder 30 includes a holder main body 31, a taper collet 32, a lock nut 33, and the like. Holder body 3
Reference numeral 1 denotes a taper shank 311 inserted into a main shaft of a machine tool (not shown), a gripping flange 312 formed at a large-diameter end of the taper shank 311, and an anti-taper shank of the flange 312. It has a cylindrical tool mounting portion 313 extending from the end face on the side of the portion 311 in the direction opposite to the tapered shank portion 311 so as to coincide with the axis, and a tapered hole 314 near the tip in the tool mounting portion 313. It is formed so as to coincide with the axis. A male screw 3 into which a lock nut 33 is screwed is provided on the outer peripheral surface of the tip of the tool mounting portion 313.
15 are formed.

[0003] The taper collet 32 grips the shank portion 341 of the tool 34 and has a structure to be fitted into a tapered hole 314 of a tool mounting portion 313. The taper collet 32 is arranged concentrically inside the lock nut 33, and by engaging a ring-shaped protrusion 331 provided on the inner periphery of the lock nut 33 with a ring-shaped groove 321 formed on the outer periphery of the lower end thereof. Both are connected so as to be relatively rotatable. Reference numeral 35 denotes a steel cover that covers the tool insertion opening 332 of the lock nut 33 so that chips and the like do not enter the collet or the holder body.
5 is fixed to the lock nut 33.

When the tool 34 is chucked in the tool holder 30 configured as described above, the lock nut 33 with the tapered collet 32 mounted thereon is attached to the tool mounting portion 3.
Then, the tapered collet 32 is temporarily inserted into the tapered hole 314 of the tool mounting portion 313. In this state, the shank portion 141 of the tool 14 is
After the tool is inserted into the taper collet 32 from the tool insertion opening 332, the lock nut 33 is tightened. This allows
The taper collet 32 is the taper hole 31 of the tool mounting portion 313.
4, the shank 341 of the tool 34
Will be grasped.

[0005]

In the conventional tool holder as described above, the taper collet 32 is tightened by the lock nut 33 so that the taper hole 31 of the holder body 31 is formed.
4, the shank portion 341 of the tool 34 is gripped, so that the grip length L2 that effectively functions for gripping the tool 34 is shown in FIG. 4 with respect to the grip length L1 of the taper collet 32 itself. Thus, only the portion where the taper collet 32 and the tool mounting portion 313 overlap each other is provided.
As a result, the effective gripping length of the taper collet 32 with respect to the tool 34 is shortened, so that a sufficient gripping force cannot be obtained, and the tool 34 easily swings, adversely affecting the cutting accuracy, and being damaged by swinging the tool. There's a problem. In particular, the above problem becomes remarkable in a tool having a shank portion having a diameter of 2 mm or less.

Therefore, as a measure for solving the above problem, it is conceivable to increase the length of the shank fitting hole of the taper collet into which the tool shank is inserted, thereby increasing the effective gripping length of the tool shank. . However, if the shank fitting hole of the taper collet is made longer than necessary to obtain the effective gripping length of the tool shank, there is no problem if the diameter of the shank fitting hole is large, but the tool shank diameter of 2 mm or less In the case of a small-diameter shank fitting hole corresponding to the above, polishing of the inner periphery of this shank fitting hole is substantially impossible. Therefore, such a method cannot be applied to a tool holder in which a small-diameter shank portion is gripped by a holder body by a taper collet and a lock nut.

Conventionally, as a tool holder for obtaining an effective grip length with respect to a tool shank, FIG.
The structure shown in FIG. The tool holder 40 shown in FIG. 5 has a tapered shank portion 411, a hollow holder body 41 having a gripping flange portion 412 and a tool mounting portion 413 in the longitudinal direction, and an axial line formed in the tool mounting portion 413. The tapered collet 42 fitted in the tapered hole 414 and the stepped portion 416 in the hollow hole 415 of the holder main body 41 support the tapered collet 42 in the tapered hole 41.
The draw bolt 43 is drawn in. The draw bolt 43 is screwed into the taper collet 42 and tightened, whereby the taper collet 42 is pulled in and the shank portion 441 of the tool 44 is gripped.

In the tool holder 40 having such a structure, almost the entire tapered collet 42 is drawn into the tapered hole 414 by the draw bolt 43, so that a sufficient gripping length for the tool 44 can be ensured. However, since the draw bolt 43 for drawing in must be inserted into the hollow hole 415 from the rear end of the holder main body 41, the tool 44 whose taper shank portion 411 of the holder main body 41 is small and whose diameter of the shank portion is 2 mm or less is used. It is impossible in shape to insert the draw bolt 43 from the rear end of the holder main body 41 into a small holder main body applied to the above.

Therefore, conventionally, there has been known a tool holder having a small taper shank portion and capable of holding a tool by a draw bolt method even with a small holder body. A tool holder of this type will be described with reference to FIG. The tool holder 50 shown in FIG. 6 includes a holder body 51 having a taper shank portion 511, a gripping flange portion 512, and a chuck fitting portion 513 in a longitudinal direction in a series, and a taper hole 514 formed in the chuck fitting portion 513. Is provided with a collet chuck 52 that is press-fitted to the nip.

The collet chuck 52 grips a tool 53 such as a drill. The collet chuck 52 has a hollow chuck body 54 having a tapered shank portion 541 and a tool mounting portion 542 in the longitudinal direction. The collet 55 fitted in the tapered hole 543 formed in this way and the step portion 545 in the hollow hole 544 of the chuck body 54 are supported.
A draw bolt 56 for pulling the collet 55 into the tapered hole 543 is provided. The draw bolt 56 is screwed into the collet 55 and tightened, whereby the collet 55 is pulled in and the shank portion 531 of the tool 53 is gripped. I have. Further, a flange portion 56 is formed at an outer peripheral portion located at a boundary between the taper shank portion 541 and the tool mounting portion 542 of the chuck body 54.

However, in the tool holder 50 shown in FIG. 6, the tapered shank 541 of the collet chuck 52 is inserted into the tapered hole 514 of the holder main body 51 until the flange 56 comes into contact with the tip end surface of the holder main body 51. Since the collet chuck 52 is connected to the holder main body 51 by press-fitting, when the collet chuck 52 is removed from the holder main body 51 when the tool 53 is exchanged, a heating / cooling device for unchucking is used. And the like, and there is a problem that the equipment cost for unchucking and the management cost thereof increase.

SUMMARY OF THE INVENTION The present invention has been made to solve the above-mentioned conventional problems, and an object of the present invention is to easily unchucking a collet chuck chucked by press-fitting into a holder body by a simple operation. Another object of the present invention is to provide a tool holder capable of reducing the cost of an unchucking system and a method for unchucking the tool holder. Further, according to the present invention, in a tool holder having a small taper shank portion and capable of holding a tool by a draw bolt method even for a small holder main body, when supplying air or coolant for cutting to the tool, Provided is a tool holder configured to prevent scattering of a cutting fluid.

[0013]

SUMMARY OF THE INVENTION In order to achieve the above object, the present invention provides a holder body having a chuck fitting portion, wherein the holder body is provided in the chuck fitting portion from a front end face to a rear end of the chuck fitting portion. A tool holder including a collet chuck that is press-fitted into a tapered hole formed so as to have a small diameter according to an axis thereof, wherein the collet chuck includes a tapered shank portion that is press-fitted into a tapered hole of the holder body. A hollow chuck body having a tool mounting portion connected to the front end of the tapered shank portion so as to be aligned with the axis thereof, and a collet which is fitted in a tapered hole formed so as to have an axis aligned with the tool mounting portion and grips the tool. The collet, which is axially supported by a support portion provided in a hollow hole of the chuck body and is drawn into the taper hole of the tool mounting portion by the collet; A draw bolt to be gripped, formed along the outer periphery at a boundary between the tapered shank portion and the tool mounting portion, and the chuck is formed when the tapered shank portion of the chuck body is press-fitted into the tapered hole of the holder body and joined. And a flange portion closely contacting the distal end surface of the fitting portion, wherein a male screw portion is formed on the outer peripheral surface of the flange portion, and the male screw portion of the flange portion is pulled out when the collet chuck pressed into the tapered hole of the holder body is pulled out. An unchucking jig having an internal thread portion screwed into the male screw portion until the unengaging jig is pressed against the tip end surface of the chuck fitting portion. The collet chuck is moved forward by relative rotation of the unchucking jig and the holder body in a direction in which the flange portion enters the unchucking jig in the fitted state. Characterized in that it is configured to pull the tapered bore of the holder body. Further, the present invention is characterized in that a dustproof cover is engaged with a tip end of the collet chuck on a tool mounting side, and the dustproof cover is screwed to the male screw portion. Further, the present invention is characterized in that a through hole is formed in an axial direction of the draw bolt so that a fluid such as air or coolant can be supplied from a rear end of the holder body.

Further, the present invention comprises a holder main body and a collet chuck, wherein the collet chuck has a chuck main body having a tapered shank portion and a collet for holding a tool, and is inserted from a rear end of the chuck main body. The collet is pulled into the chuck body from the front end side by a draw bolt to grip a tool, and the taper shank portion of the chuck body is pressed into a taper hole provided in the holder body to thereby insert the collet chuck into the holder body. A method of unchucking the collet chuck coupled to the holder body in a tool holder coupled to the holder body, wherein the chuck body has a tapered shank portion that is press-fitted into a tapered hole of the holder body. It has a flange that is in close contact with the distal end surface, and the flange has an external thread on its outer peripheral surface. An unchucking jig screwed into the male screw portion of the flange portion, and the male screw is held on the unchucking jig until the screw-side tip thereof is pressed against the tip end surface of the holder body. The collet chuck is screwed onto the holder body in this state by relatively rotating the unchucking jig and the holder body in a direction in which the flange enters the unchucking jig. It is characterized by being pulled out from the tapered hole.

In the tool holder and the unchucking method of the present invention, the unchucking jig and the holder main body are connected to each other by the flange while the unchucking jig is screwed into the male thread of the flange. Relative rotation is performed in a direction to enter the inside of the unchucking jig. With the relative rotation of the unchucking jig and the holder body, the flange enters the unchucking jig, and at the same time, the screw-side tip of the unchucking jig presses the tip surface of the holder body. Then, the taper shank portion of the chuck body acts so as to be removed from the taper hole of the holder body. This allows
The collet chuck is withdrawn from the tapered hole of the holder body. Therefore, according to the present invention, the collet chuck chucked by press-fitting into the holder body can be easily unchucked by a simple operation, and the cost of the unchucking system can be reduced. Further, in the tool holder of the present invention, in a state in which the unchucking jig is not screwed into the male screw portion of the flange portion, a dustproof cover is engaged with a tool mounting side end of the collet chuck, and the dustproof cover is provided. Is screwed into the male screw portion to prevent chips or dust from adhering to the male screw portion to which the unchucking jig is screwed. And the fluid such as air or coolant can be prevented from scattering from the slot of the collet from the rear end of the holder body.

[0016]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a sectional view showing an example of a tool holder and an unchucking jig according to an embodiment of the present invention. FIG. 2 is a sectional view showing a collet chuck from a holder body using the unchucking jig according to the embodiment of the present invention. It is an explanatory view at the time of extracting.

A tool holder 10 shown in FIG. 1 is used to hold a tool 9 such as a drill having a shank diameter of 2 mm or less, and includes a holder body 11 and a collet chuck 12, and a tool for unchucking. A jig 13 is provided. The holder body 11 includes a tapered shank portion 111 that is inserted into a main shaft of a machine tool (not shown), a gripping flange portion 112 formed at a large-diameter end of the tapered shank portion 111, and a flange portion 112. It has a cylindrical chuck fitting portion 113 extending from the end face on the side opposite to the taper shank portion 111 so as to coincide with the axis in a direction opposite to the taper shank portion 111. Is formed such that the tapered hole 114 is aligned with the axis. The diameter of the tapered hole 114 becomes smaller as going backward from the front end surface 113A of the chuck fitting portion 113.
It has a gentle taper angle such as / 100. In addition,
The total length of the holder main body 11 in this embodiment is 2 mm.
For example, 6 corresponding to the tool 9 having the following shank diameter
It has a length of about 7 mm.

The collet chuck 12 includes a hollow chuck body 12A, a collet 12B having a slot for holding the tool 9, and a draw bolt 12C. The chuck body 12A includes a tapered shank portion 12A1 press-fit into the tapered hole 114 of the holder body 11, a tool mounting portion 12A2 connected to the front end of the tapered shank portion 12A1 so as to coincide with the axis thereof, and a tapered shank portion 12A1. It has a flange 12A3 formed along the outer periphery at a boundary with the mounting portion 12A2, and the flange 12A3 is
13 is formed to have a diameter smaller than the outer diameter of the front end face 113A,
Further, a male screw portion 12A4 is formed on the outer peripheral surface of the flange portion 12A3. Further, the tapered shank portion 12A1 has a gentle taper angle such as 1/100 which becomes smaller in diameter from the side with the tool mounting portion 12A2 toward the rear end. The total length of the collet chuck 12 is about 42 mm.

Inside the tool mounting portion 12A2, a tapered hole 12A5 having a smaller diameter as it goes backward from the distal end surface of the tool mounting portion 12A2 is formed so as to coincide with the axis, and a collet 12B is fitted into the tapered hole 12A5. Is done. A support portion 12A7 that rotatably supports a draw bolt 12C inserted from the rear end into the hollow hole 12A6 of the chuck body 12A is provided concentrically at a position near the rear end in the hollow hole 12A6 of the chuck body 12A. ing. Draw bolt 1
2C is configured to hold the tool 9 by pulling the collet 12B fitted into the tapered hole 12A5 of the tool mounting portion 12A2 backward.

The unchucking jig 13 is used to pull out the collet chuck 12 press-fitted into the tapered hole 114 of the holder body 11 when the male screw portion 12A of the flange portion 12A3 is pulled out.
4 and has a cylindrical shape having an inner diameter corresponding to the outer diameter of the flange portion 12A3. A female screw portion 131 to be screwed to the male screw portion 12A4 of the flange portion 12A3 is formed on the inner peripheral surface of the unchucking jig 13 on the fitting side to the flange portion 12A3.

In the tool holder 10 configured as described above, when the tool 9 is to be gripped by the chuck body 12A, as shown in FIG. 1, the collet 12B is inserted into the tapered hole 12A5 of the chuck body 12A. The draw bolt 12C is inserted into the hollow hole 12A6 from the rear end of the chuck body 12A, and screwed into the female screw portion 12B1 provided at the insertion end of the collet 12B, thereby temporarily fixing the collet 12B. In this state, the shank portion 91 of the tool 9 is
After inserting the collet 12B into the collet 12B, the draw bolt 12C is tightened by a jig (not shown). Thereby, the tool 9 is chucked to the chuck body 12A.

Next, a case where the collet chuck 12 holding the tool 9 is chucked to the holder body 11 will be described. In this case, the flange portion 12A3 is attached to the front end surface 113A of the chuck fitting portion 113 of the holder body 11 by using a dedicated jig in which the tapered shank portion 12A1 of the chuck body 12A is not shown in the tapered hole 114 of the holder body 11. Press in until pressed. Thereby, the collet chuck 12 is firmly chucked to the holder main body 11.

Next, a case where the collet chuck 12 is unchucked from the holder body 11 will be described.
In this case, as shown in FIG. 2, the unchucking jig 13 is inserted from the tool mounting portion 12A2 of the collet chuck 12, and the female screw portion 131 is screwed into the male screw portion 12A4 of the flange portion 12A3. King jig 13
Is brought into contact with the front end surface 113A of the chuck fitting portion 113 of the holder body 11. After fixing the unchucking jig 13 in this state to fixing means such as a vise (not shown), the holder main body 11 is attached to the flange portion 112 of the holder main body 11 by using a tool such as a wrench (not shown). Is rotated in a direction in which the screw is screwed into the unchucking jig 13. When the holder body 11 is rotated,
Simultaneously with the flange portion 12A3 being screwed into the unchucking jig 13, the screw-side tip of the unchucking jig 13 presses the front end surface 113A of the chuck fitting portion 113,
The tapered shank portion 12A of the collet chuck 12 acts so as to be pulled out from the tapered hole 114 of the holder body 11. Thereby, the tapered shank portion 12A of the collet chuck 12 is pulled out from the tapered hole 114 of the holder body 11.

Therefore, according to the tool holder of this embodiment, the collet chuck 12 chucked by press-fitting into the holder body 11 can be easily unchucked by a simple operation, and the jig used for unchucking is used. 13 also has a simple structure, so that the unchucking system can be simple, eliminating the need for a conventional heating / cooling device for unchucking, thus reducing the cost of unchucking. can do. Further, according to the tool holder of this embodiment, the collet 12B inserted into the tapered hole 12A5 of the chuck main body 12A is pulled in by the draw bolt 12C inserted from the rear end of the chuck main body 12A, so that the tool 9 is gripped. Since the collet chuck 12 is used, a sufficient gripping length for the tool 9 can be ensured.

Incidentally, the unchucking jig 13 in the present invention is not limited to the structure shown in the above embodiment. In the above embodiment, the holder body 11
Chuck 12 chucked by press-fitting
When extracting the holder body 11 from the holder body 11, the unchucking jig 12 is fixed to a fixing means such as a vise, and the holder body 1
Although the method of rotating and extracting 1 has been described, the present invention is not limited to this, and the method of relatively rotating the unchucking jig 12 and the holder body 11 in the direction in which the collet chuck 12 is pulled out of the holder body 11 is described. It may be.

FIG. 3 is a side sectional view showing a modification of the tool holder according to the present invention. In this modified example, a tool holder 10 that supplies a cutting fluid such as air or coolant to the tool 9 attached to the tip side of the tool holder 10 through the inside of the tool holder 10 is shown. The same parts as those in the above-described embodiment are denoted by the same reference numerals, and the description thereof will be omitted, and different points will be described.

A different point from the above-described embodiment according to this modification is that a through hole 1 axially penetrates a draw bolt 12C provided in a rear hollow hole 12A6 of a collet chuck 12.
2D is provided, and a cutting fluid supplied from the rear end portion of the tool holder body 11 is formed on a collet 12B by a slotting 12E.
, So that the tool 9 and the workpiece are supplied from the tip side of the collet 12B, and the dustproof cover 60 is engaged with the tool 9 mounting side tip of the collet chuck 12;
A female screw 60 formed on the inner peripheral surface of the rear end of the dustproof cover 60
A is configured so that A is screwed into the male screw portion 12A4, and a through hole 60B through which the tool 9 penetrates loosely is provided at the center of the tip end side of the dustproof cover 60. In some cases, a through-hole is provided at the center of the tool 9 in the axial direction, and a cutting fluid is supplied using the through-hole. However, when the cutting tool (tool) shank diameter is 2 mm or less, this through-hole is It is difficult to form, and the fluid is supplied from the slot 12E of the collet 12B.

In the tool holder 10 according to this modified example, by providing the dustproof cover 60, the cutting fluid supplied from the slit 12E formed in the collet 12B is passed through the through hole 60B formed in the central portion on the tip side. Supply to the tool 9. In the case of a small-diameter blade, the rotation speed becomes high and the cutting fluid scatters due to the cutting speed.
The above problem is solved because the tool 9 is supplied to the tool 9 through the through hole 60B.

When the collet chuck 12 is to be unchucked from the holder main body 11, the dustproof cover 60 is removed from the collet chuck 12, and as shown in FIG. The tool 13 is inserted from the tool mounting portion 12A2 of the collet chuck 12, the female screw portion 131 is screwed into the male screw portion 12A4 of the flange portion 12A3, and the screwing tip of the unchucking jig 13 is chuck-fitted to the holder body 11. Unchucking is performed by making contact with the front end surface 113A of the joining portion 113. Therefore, since the male screw portion 12A4 formed on the collet chuck 12 is always covered by the dustproof cover 60 during the operation, the attachment of cutting chips or dust during the operation can be prevented.

[0030]

As described above, according to the tool holder and the unchucking method of the present invention, the collet chuck chucked by press-fitting into the holder body can be easily unchucked by a simple operation, and the unchucking can be performed easily. Since the jig used for chucking may have a simple structure, the unchucking system may be simple, and the cost for unchucking may be reduced. According to the present invention, since the collet inserted into the tapered hole of the chuck body is pulled in by the draw bolt inserted from the rear end of the chuck body, the collet chuck having a structure for gripping the tool is used. This has the effect that a sufficient gripping length can be ensured. In addition, it is possible to prevent the cutting fluid from being scattered due to a high rotation speed, which is likely to occur on a small-diameter blade (tool).
There is an effect that it is possible to prevent chips, dust and the like during the operation from adhering to the male screw portion formed on the collet chuck.

[Brief description of the drawings]

FIG. 1 is a sectional view showing an example of a tool holder and an unchucking jig according to an embodiment of the present invention.

FIG. 2 is an explanatory diagram when a collet chuck is extracted from a holder main body using an unchucking jig according to an embodiment of the present invention.

FIG. 3 is a sectional view showing a modification of the tool holder according to the embodiment of the present invention.

FIG. 4 is a sectional view of a conventional tool holder.

FIG. 5 is a sectional view of a conventional tool holder.

FIG. 6 is a sectional view of a conventional tool holder.

[Explanation of symbols]

 9 Tool 10 Tool Holder 11 Holder Body 111 Taper Shank Part 112 Flange Part 113 Chuck Fitting Part 114 Tapered Hole 12 Collet Chuck 12A Chuck Body 12B Collet 12C Draw Bolt 12A1 Taper Shank Part 12A2 Tool Attachment Part 12A3 Flange Part 12A4 Male Thread Part 12A5 Hole 13 Unchucking jig 131 Female screw part 60 Dustproof cover

 ────────────────────────────────────────────────── ─── Continuing on the front page (72) Inventor Yusaku Yamamoto 1-6-153 Motomachi, Higashiosaka-shi, Osaka F-term in Niken Kozaku Co., Ltd. (reference) 3C032 BB12 FF05 JJ16

Claims (7)

[Claims] A holder body having a chuck fitting portion;
A tool holder including a collet chuck which is press-fitted into a tapered hole formed in the chuck fitting portion so as to have a smaller diameter as going from a front end surface to a rear end of the chuck fitting portion so as to have a smaller diameter. The collet chuck includes a hollow chuck body having a taper shank portion press-fit into a tapered hole of the holder body and a tool mounting portion connected to the front end of the taper shank portion so as to be aligned with the axis thereof. A collet which is fitted in a tapered hole formed so as to have an axis coincident with the grip, and which holds the tool; and a collet which is axially penetrated and supported by a support portion provided in a hollow hole of the chuck main body and which is inserted into the taper hole of the tool mounting portion. A draw bolt that grips the tool by drawing in, formed along the outer periphery at a boundary between the tapered shank portion and the tool mounting portion, And a flange portion which is in close contact with the distal end surface of the chuck fitting portion when the tapered shank portion of the chuck body is press-fitted into the tapered hole of the holder body and is coupled thereto, and a male screw portion is formed on the outer peripheral surface of the flange portion. An unchucking jig having an internal thread portion screwed into an external thread portion of the flange portion when pulling out the collet chuck press-fitted into the tapered hole of the holder main body, wherein the unchucking jig is provided. The unchucking jig and the holder body are inserted into the unchucking jig in a state where the unchucking jig and the holder main body are screwed into the male screw portion until the tip of the screwing side is pressed against the tip surface of the chuck fitting portion. A tool holder characterized in that a collet chuck is pulled out from a tapered hole of a holder body by relatively rotating in a direction of entry. 2. The taper hole of the holder main body is 1/10
The tool holder according to claim 1, wherein the tool holder has a gentle taper angle such as zero. 3. The tool holder according to claim 1, wherein the taper shank portion of the chuck body has a gentle taper angle such as 1/100. 4. The tool holder according to claim 1, wherein a dustproof cover is engaged with a tip end of the collet chuck on a tool mounting side, and the dustproof cover is screwed to the male screw portion. 5. The draw bolt according to claim 1, wherein a through hole is formed in an axial direction of the draw bolt so that a fluid such as air or a coolant can be supplied from a rear end of the holder body. Tool holder. 6. A collet chuck comprising a holder body and a collet chuck, wherein the collet chuck has a chuck body having a tapered shank portion and a collet for holding a tool, and the collet is formed by a draw bolt inserted from a rear end of the chuck body. A tool holder for holding the tool by pulling the collet chuck into the chuck body from the front end side, and pressing the taper shank portion of the chuck body into a taper hole provided in the holder body to couple the collet chuck to the holder body. The method of unchucking the collet chuck coupled to the holder main body, wherein the chuck main body is in close contact with the tip end surface of the holder main body when the tapered shank portion is press-fitted into the tapered hole of the holder main body. A flange portion, wherein the flange portion has an external thread portion on an outer peripheral surface thereof; An unchucking jig to be screwed to the male screw portion, and screwing the unchucking jig to the male screw portion until the screw-side tip thereof is pressed against the tip end surface of the holder main body; In this state, the collet chuck is pulled out from the tapered hole of the holder body by relatively rotating the unchucking jig and the holder body in a direction in which the flange portion enters the unchucking jig. Tool holder unchucking method. 7. One of the unchucking jig and the holder main body is fixed by a fixing means such as a vise, and the other unchucking jig or the holder main body which is not fixed by the fixing means is rotated. The method according to claim 6, wherein the collet chuck is pulled out from the tapered hole of the holder body.