JP2000246585A - Tool holder - Google Patents

Abstract

(57) [Summary] [PROBLEMS] To easily cope with tool exchange with a simple configuration. A collet (6) is fitted into a tapered hole (2b) of a holder body (1), and a nut (7) is screwed into a small diameter part (4) of the holder body (1). Collet ring 8 between collet 6 and nut 7
The inner peripheral surface of the collet ring 8 is engaged with the outer peripheral surface of the collet 6, and the outer peripheral surface of the collet ring 8 is
Rotatably connected to. A nut ring 11 having a tool insertion hole 13 is screwed into a front portion of the inner peripheral surface of the nut 7. The inner diameter of the tool insertion hole 13 is slightly larger than the outer diameter of the tool T, and a pair of fluid ejection grooves 14 extending in the axial direction are formed at equal intervals on the inner peripheral surface of the tool insertion hole 13. The portions other than the fluid ejection groove 14 prevent the leakage of the fluid and maintain the pressure of the fluid high, so that the fluid is ejected from the fluid ejection groove 14 to the tip of the tool T.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a tool holder for holding a tool in a detachable manner and injecting a fluid such as coolant, oil mist, air, etc., along the outer peripheral surface of the tool to the tip of the tool.

[0002]

2. Description of the Related Art Conventionally, a tool holder of this kind has been disclosed in
No. 17452, JP-A-8-112731, and the like. In these tool holders, the coolant or cutting fluid that has flowed into the rear portion of the holder main body passes through the coolant or liquid supply passage of the holder main body and the slot of the collet located in the passage to the front of the holder main body. Distribute. In the tool holder disclosed in Japanese Unexamined Utility Model Publication No. 7-17452, the coolant circulating in the front part of the holder body is sprayed to the tip of the tool from a plurality of nozzle holes of the nozzle disk or a clearance on the outer periphery of the tool. 8-112732
In the tool holder disclosed in Japanese Unexamined Patent Application Publication No. H11-115, the cutting fluid is jetted from the gap on the outer periphery of the tool to the tip of the tool.

[0003]

SUMMARY OF THE INVENTION
In the tool holder disclosed in Japanese Patent No. 17452, since the area of the gap on the outer periphery of the tool is large, the pressure of the coolant is greatly reduced, and the coolant may not reach the tip of the tool.
Further, when the length of the tool changes, there is a possibility that the coolant may be injected to a position off the tip of the tool. Furthermore,
Is the nozzle disc pressed and fixed directly on the nut?
Since it is pressed and fixed to the adapter engaged with the collet,
It is necessary to completely remove the nut from the holder body when exchanging the tool, and the collet comes off together with the adapter, resulting in poor operability of exchanging the tool.

On the other hand, in the tool holder disclosed in Japanese Patent Application Laid-Open No. H8-112731, since the area of the gap around the outer periphery of the tool is large as described above, the pressure of the cutting fluid is greatly reduced and the cutting fluid does not reach the tip of the tool. There is a fear. In addition, the nozzle for injecting the cutting fluid is detachably incorporated in the hole of the cap body, and the nozzle incorporates a ball valve having a hole and a spring for crimping at the outlet of the through hole of the screw member, and Since the direction of injection of the cutting fluid is changed by adjusting the direction of the holes, the structure is extremely complicated and the workability is poor.

An object of the present invention is to solve the above-mentioned problems,
It is an object of the present invention to provide a tool holder which can easily cope with tool exchange with a simple configuration.

[0006]

According to the present invention, there is provided a tool holder having a passage through which a fluid flows, the holder body being mountable to a main shaft of a machine tool, and a front part of the holder body. A collet for tightening the installation tool to
A nut that is screwed to the front part of the holder body to drive the collet; and a nut ring that has a tool insertion hole for inserting the tool and is screwed to an inner peripheral surface of the nut. An inner diameter is made slightly larger than an outer shape of the tool, and a plurality of grooves extending in an axial direction and passing the fluid are provided on an inner peripheral surface of the tool insertion hole.

[0007]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described in detail with reference to the illustrated embodiment. FIG. 1 is a partial cross-sectional view of the first embodiment, and FIG. 2 is a right side view. The holder main body 1 has a rear end surface 1a held on a main shaft of a machine tool and a front end surface on a side holding a tool T. 1b, and the holder main body 1 is formed with a through hole 2 penetrating the rear end face 1a and the front end face 1b. A fluid such as a coolant and an oil mist is supplied to the through hole 2. When the oil mist is supplied, a small amount of lubrication becomes possible, thereby improving the oil consumption and the environment. . The through hole 2 includes a straight hole 2a on the rear end face 1a and a tapered hole 2b on the front end face 1b.
The diameter of the tapered hole portion 2b is enlarged toward the rear end surface 1a. A tapered portion 3 attached to the main shaft is formed on the rear end surface 1b side of the outer peripheral surface of the holder main body 1, a small diameter portion 4 is provided on the front end surface 1b side, and a flange gripped by a tool changing device is provided in the middle. The member 5 is fixed.

A tapered collet 6 is fitted in the tapered hole portion 2b of the holder body 1 so as to be movable back and forth. The collet 6 is formed with a plurality of slits (not shown) and has a reduced diameter inward. It is possible to do. The female screw 7 at the rear of the nut 7 is attached to the male screw 4a of the small diameter portion 4 of the holder body 1.
a is screwed together, whereby a nut 7 is attached to the small diameter portion 4, and a collet ring 8 is interposed between the collet 6 and the nut 7. The inner peripheral surface of the collet ring 8 is engaged with the outer peripheral surface of the collet 6, and the outer peripheral surface of the collet ring 8 is rotatably connected to a nut 7 via a ball 9. The female screw portion 7b at the front of the nut 7 has O
Male thread portion 11a of nut ring 11 via ring 10
Is screwed.

A fluid receiving chamber 12 having a straight surface 12a for receiving a fluid is formed on a rear surface of the nut ring 11, and a tool insertion hole 13 for inserting a tool T is formed on an axis of the nut ring 11. Have been. Tool insertion hole 13
Is slightly larger than the outer diameter of the tool T,
The fluid is prevented from leaking from between the outer peripheral surface of the tool T and the inner peripheral surface of the tool insertion hole 13. On the inner peripheral surface of the tool insertion hole 13, for example, a pair of fluid ejection grooves 14 for ejecting a fluid toward the tip of the tool T are formed at equal intervals along the axial direction. On the front surface of the nut ring 11, a pair of jig retaining grooves 15 for retaining a jig such as a spanner (not shown) is formed.

In the tool holder having such a configuration, when the rear portion of the tool T is inserted into the inside of the collet 6 from the tool insertion hole 13 of the nut ring 11 and the nut 7 is tightened, the nut 7 and the collet 6 The collet 6 receives the pressing force from the inner peripheral surface of the tapered hole portion 2b while moving to the rear end surface 1a side, reduces the diameter inward, and tightens the tool T.
In the tool holder holding the tool T in this manner, the flange member 5 is gripped by the tool changing device, and the tapered portion 3 is mounted on the main shaft of the machine tool.

In such a state, when the fluid flows into the through hole 2 from the rear end face 1a side of the holder body 1, the fluid passes through the straight hole 2a of the through hole 2 and the slot of the collet 6 and the fluid receiving chamber. 12 and then into the fluid ejection grooves 14
To the tip of the tool T.

When replacing the tool T, when the tool T is within the range of holding the collet 6, the nut 7 is loosened and the tool T is removed. If the diameter of the tool T is the same and only the length is different, the nut ring 11
The tool T is attached through the tool insertion hole 13 as described above. At this time, the projection length of the tool T changes, but the fluid is ejected along the axial direction, so that the fluid reaches the tip of the tool T without fail.

When the tool T is replaced with a tool T having a different diameter, the nut 7 is loosened and the tool T is pulled out. Rotate 11 and remove from nut 7. Then, the tool insertion hole 1 that matches the diameter of the new tool T
The nut ring 11 having 3 is screwed into the nut 7, and after inserting a new tool T into the tool insertion hole 13, the nut 7 is tightened.

On the other hand, when the tool T is not within the holding range of the collet 6, the nut 7 is loosened, the tool T is pulled out, the nut 7 is further loosened, and the nut 7 holding the collet 6 is removed from the holder body 1. Next, the collet 6 is reduced in diameter and removed from the collet ring 8, and the collet 6 corresponding to a new tool T is attached to the collet ring 8. Also,
The nut ring 11 is removed from the nut 7, and a new nut ring 11 having a fluid injection groove 14 corresponding to a new tool T is screwed into the nut 7. Then, the nut 7 with the new collet 6 and the nut ring 11 is inserted into the holder body 1.
Then, the tool T is inserted into the tool insertion hole 13 and the nut 7 is tightened.

As described above, in the first embodiment, the inner diameter of the tool insertion hole 13 of the nut ring 11 is slightly larger than the outer diameter of the tool T, and the inner peripheral surface of the tool insertion hole 13 extends in the axial direction. Since only a pair of fluid ejection grooves 14 are formed,
In addition to simplifying the configuration, it is possible to prevent the fluid from leaking from portions other than the fluid ejection groove 14 and to eject the fluid from the fluid ejection groove 14 to the tip of the tool T at a high pressure.

When the tools T having different lengths are held, there is no need to adjust the injection angle of the fluid as in the prior art. When the tools T are within the holding range of the collet 6,
Since tools T having different diameters can be dealt with by replacing only the nut ring 11, workability for replacing the tool T is improved.

FIG. 3 is a partial cross-sectional view of the second embodiment, and FIG. 4 is a right side view. A projection 21a made of, for example, a hexahedron is provided on the front side of the nut ring 21; Is provided with a fluid receiving chamber 22 having a straight surface 22a. A tool insertion hole 23 and a fluid ejection groove 24 are formed in the nut ring 21 including the protruding portion 21 a, and a jig retaining groove 25 is formed on a front surface of the nut ring 21.

In the second embodiment, since the fluid ejection groove 24 is longer than the fluid ejection groove 14 of the first embodiment, the fluid can be ejected farther than in the first embodiment. Further, when the nut ring 21 is rotated, the protruding portion 21a can be used, and other effects similar to those of the first embodiment can be achieved.

FIG. 5 is a partial sectional view of the third embodiment.
A projection 31a is provided on the front side of the nut ring 31, and a fluid receiving chamber 32 having a tapered surface 32a is provided on the rear surface of the nut ring 31. The nut ring 31 including the protruding portion 31a has a tool insertion hole 33 and a fluid ejection groove 3.
4 are formed. The small-diameter portion of the tapered surface 32 a of the fluid receiving chamber 22 is smoothly connected to the fluid ejection groove 34.

In the third embodiment, since the tapered surface 32a of the fluid receiving chamber 32 smoothly communicates with the fluid ejection groove 34, the fluid smoothly flows from the fluid receiving chamber 32 into the fluid ejection groove 34, The fluid can be ejected farther than in the second embodiment,
In other respects, the same effect as the configuration of the second embodiment except for the jig retaining groove 25 can be achieved.

In the above-described first to third embodiments, a pair of fluid ejection grooves 14, 24, 34 are provided at equal intervals, but a larger number of fluid ejection grooves 14, 24, 34 are provided at equal intervals. If provided, the fluid can be evenly jetted to the tip of the tool T.
Further, if the portions other than the fluid ejection grooves 14, 24, and 34 are sealed with a seal member, the pressure of the fluid can be further increased. Further, the jig locking hole grooves 15 and 25 can have any shape as long as the jig can be engaged. Then, the protruding portions 21a, 31 of the second and third embodiments
Although a is a hexahedron, it may be a 3- to 5-hedron.

[0022]

As described above, in the tool holder according to the present invention, the inner diameter of the tool insertion hole is made slightly larger than the outer diameter of the tool, and the inner peripheral surface of the tool insertion hole is extended in the axial direction. Since only the groove is provided, the structure is simple, the leakage of the fluid from the tool insertion hole is small, the pressure of the fluid is small, and the fluid can be reliably jetted to the tip of the tool.

Further, when holding tools having different lengths, it is not necessary to adjust the jetting direction of the fluid as in the prior art. Only the nut ring needs to be replaced, and the work of removing the nut from the holder main body as in the related art is not required, and the workability is improved.

[Brief description of the drawings]

FIG. 1 is a partial sectional view of a first embodiment.

FIG. 2 is a right side view.

FIG. 3 is a partial sectional view of a second embodiment.

FIG. 4 is a right side view.

FIG. 5 is a partial sectional view of a third embodiment.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Holder main body 2 Through hole 6 Collet 7 Nut 8 Collet ring 11, 21, 31 Nut ring 13, 23, 33 Tool insertion hole 14, 24, 34 Fluid ejection groove 15, 25 Jig retaining groove 21a, 31a Projection

Claims (5)

[Claims] 1. A holder main body having a passage through which a fluid flows, the holder main body being mountable on a main shaft of a machine tool, a collet for tightening a mounting tool to a front portion of the holder main body, and a collet screwed to a front portion of the holder main body. A nut for driving a collet, and a nut ring having a tool insertion hole for inserting the tool and being screwed to an inner peripheral surface of the nut, wherein the inner diameter of the tool insertion hole is slightly larger than the outer shape of the tool. A tool holder, wherein a plurality of grooves extending in the axial direction and allowing the fluid to pass therethrough are provided on an inner peripheral surface of the tool insertion hole. 2. The tool holder according to claim 1, wherein a collet ring is attached to an outer periphery of the collet, and the collet ring is rotatably connected to the nut. 3. A projection having a tool insertion hole having the same inner diameter as the tool insertion hole and an axially extending groove communicating with the groove is provided on a front surface of the nut ring.
Tool holder according to 1. 4. The tool holder according to claim 3, wherein the protrusion is a polyhedron. 5. The tool holder according to claim 1, wherein a jig engaging portion is provided on a front surface of the nut ring.