JPH0675607U - Collet chuck - Google Patents

Abstract

(57) [Abstract] [Purpose] When cutting the coolant while drawing it out from the front end of the split groove of the taper collet, there is no wasteful leakage of the coolant in the chuck part, good coolant utilization efficiency and cooling efficiency, and Provided is a collet chuck which does not become dirty and does not impair the lubricating function between the tightening nut and the thrust ring. A tool 8 is inserted into a taper hole 2 of a chuck body 1 via a taper collet 3 and fixed by tightening a tightening nut 4. In the chuck body 1, a coolant communicating with the taper hole 2 is provided inside the chuck body 1. Equipped with a liquid conduit 9
An annular seal layer 12 made of an elastic material is interposed between a front end surface 10 of the chuck cylinder portion 1 a and an inner end surface 11 of a thrust ring 6 fitted on the inner circumference of the tightening nut 4.

Description

[Detailed description of the device]

[0001]

[Industrial applications]

 The present invention relates to a collet chuck for fixing a tool to a chuck body via a taper collet and a tightening nut, and more particularly to a collet chuck suitable for machining while drawing out a coolant from a front end of a split groove of the taper collet.

[0002]

[Prior art]

 Generally, as shown in FIGS. 1 to 3, in a collet chuck, a tool 8 is fitted through a tapered collet 3 into a narrow tapered hole 2 opened at the front end of a chuck body 1, and the front portion of the body 1 is fitted. When the tightening nut 4 is externally fitted and tightened, the taper collet 3 is pushed into the taper hole 2 to reduce the diameter, and thus the tool 8 is firmly fixed to the chuck body 1. The tapered collet 3 is provided with a plurality of split grooves 5a and 5b which are alternately cut from the front and rear ends in the axial direction, and has a tapered surface 3a on the outer periphery of the front end and an annular groove 3b adjacent thereto. have. A thrust ring 6 is fitted on the front side of the inner periphery of the tightening nut 4 via a ball bearing 7 so as to be relatively rotatable and non-separable. A taper collet is attached to the front side of the inner periphery of the thrust ring 6. A tapered taper surface 6a facing the taper surface 3a of the collet 3 and an annular projecting edge portion 6b engaging with the annular groove 3b of the collet 3 are formed on the rear side thereof.

In cutting using such a collet chuck, coolant supplied from the machine tool is communicated with the tapered hole 2 in order to prevent deterioration of workability due to overheating of the tool 8 and the cutting position. The liquid is introduced into the split grooves 5a and 5b of the taper collet 3 from the liquid guide path 9 and jetted forward along the tool 8 from the open front end of the split groove 5a as shown by an arrow A in FIG. Means to wet and cool the site are used.

[0004]

However, in the related art, when the cutting process is performed while cooling with the coolant as described above, the supply pressure of the coolant is high, so that the tightening nut 4 and the thrust ring are not provided. The coolant leaks from the interface S1 with 6 and the screw interface S2 between the tightening nut 4 and the chuck cylinder 1A as shown by the arrow B, and the amount of coolant contributing to the cooling of the tool 8 and the cutting portion is reduced accordingly. It is economical, cooling efficiency is reduced to impede high-speed cutting performance, and because the entire chuck part rotates at high speed, the leaked coolant scatters due to centrifugal force and pollutes a wide area around it, creating a work environment. In addition to the deterioration, it causes a malfunction of peripheral equipment, and there is a problem that the lubricating oil of the ball bearing 7 is deteriorated or replaced by the coolant and the lubricating function is lost.

In view of the above situation, the present invention eliminates wasteful leakage of the coolant in the chuck portion when performing the cutting work while drawing out the coolant from the front end of the split groove of the taper collet, so that the utilization efficiency of the coolant and the coolant can be improved. The objective is to provide a collet chuck that has good cooling efficiency, does not stain the surrounding area, and does not impair the lubrication function between the tightening nut and thrust ring.

[0006]

[Means for Solving the Problems]

 In order to achieve the above-mentioned object, the present invention comprises a tightening nut 4 which is inserted into a taper hole 2 of a chuck body 1 through a taper collet 3 and is externally screwed to a front portion of the chuck body 1. In a collet chuck for fixing a collapsing tool 8 by tightening, a coolant liquid guide path 9 communicating with the tapered hole 2 is provided inside the chuck body 1, a front end surface 10 of the chuck cylinder portion 1a, and an inner circumference of a tightening nut. In this structure, an annular seal layer 12 made of an elastic material is interposed between the thrust ring 6 and the inner end surface 11 of the thrust ring 6, which is rotatably fitted to the inner ring.

[0007]

[Action]

 The tool 8 fits the taper collet 3 into which the tool 8 is inserted into the taper hole 2 of the chuck body 1, and the tightening nut 4 is externally screwed onto the front portion of the body 1 to tighten the chuck body 1. It is firmly fixed to. When cutting is performed by rotating the entire chuck part in this state, if coolant is supplied from the machine tool side to the liquid guide path 9 of the chuck body 1, the coolant will be distributed to the split grooves 5a and 5b of the taper collet 3. It flows in and jets forward from the open front end of the split groove 5a along the tool 8 as shown by the arrow A in FIG. 3 to wet the tool 8 and the cutting portion and cool them. However, since the annular seal layer 12 is interposed between the front end surface 10 of the chuck cylinder 1a and the inner end surface 11 of the thrust ring 6, the interface S1 between the tightening nut 4 and the thrust ring 6 and the tightening The coolant cannot penetrate into the screwing interface S2 between the nut 4 and the chuck cylinder portion 1A, so that the total amount of the coolant supplied without leaking from both interfaces S1 and S2 cools the tool 8 and the cutting part. Will be involved.

[0008]

【Example】

 The basic structure of the collet chuck to which the present invention is applied is the same as the conventional structure described above. As shown in FIGS. 1 to 3, a chuck body 1 having a narrow tapered hole 2 opened at the front end is provided. It comprises a taper collet 3 having a tapered outer peripheral surface corresponding to the taper hole 2 and a tightening nut 4. The chuck body 1 is provided with the threaded portion 13a on the outer periphery of the front portion 1a having a slightly smaller diameter, and the coolant liquid guiding passage 9 which is continuous from the rear end of the tapered hole 2 to the inner rear side along the axial center. Is provided. The taper collet 3 has a plurality of split grooves 5a and 5b, which are alternately cut from the front and rear ends in the axial direction (six in the figure), and are equally formed. And an annular groove 3b adjacent thereto.

The tightening nut 4 includes a nut body 4a having a threaded portion 13b corresponding to the threaded portion 13a of the chuck body 1 on the rear side of the inner peripheral surface, and a thrust member fitted on the front side of the inner peripheral surface. It is composed of two members such as a tring 6, and both members 4a, 6 are relatively rotatable and inseparable by a ball bearing 7 loaded in an annular hole 7a formed between the mutually facing surfaces. The thrust ring 6 has an outer tapered surface 6a corresponding to the taper surface 3a of the taper collet 3 on the front side of the inner circumference and an annular projecting edge 6b on the rear side thereof. The annular projecting edge portion 6b is loosely fitted in the annular groove 3b of the taper collet 3.

In the collet chuck of the present invention, as in the conventional one, the shank portion of the tool 8 is inserted into the taper collet 3 and the taper collet 3 is fitted into the taper hole 2 of the chuck body 1. When the tightening nut 4 is externally fitted and screwed on the front portion 1a of the main body 1, the tapered surface 6a of the thrust ring 6 presses the tapered surface 3a of the tapered collet 3, and the collet 3 is divided into the split grooves 5a, The tool 8 is pressed into the taper hole 2 while being reduced in diameter due to the reduction of the width of 5b, and the tool 8 is firmly tightened on the inner peripheral surface of the collet 3. In this tightened state, the front end surface 10 of the chuck tubular portion 1a is tightened. The annular seal layer 12 is interposed between the inner ring surface 11 of the thrust ring 6 and the inner surface 11 of the thrust ring 6 as shown by phantom lines in FIGS.

In order to interpose such an annular seal layer 12, before the tool 8 is attached to the chuck body 1, a rear portion formed between the inner periphery of the nut body 1 and the outer periphery of the taper collet 3 is formed in advance. 6, the elastic ring 12a having a rectangular cross section as in the first embodiment of FIG. 4, the elastic ring 12b having a circular cross section as in the second embodiment of FIG. 5, the third embodiment of FIG. An elastic ring 12c having an X-shaped cross section as in the example, an elastic ring 12d having a V-shaped cross section as in the fourth embodiment shown in FIG. You can leave it. Instead of fitting these rings, a solution or melt of an elastic polymer material is applied and cured on the entire circumference of the corner between the inner peripheral surface of the nut body 1 and the rear end surface of the thrust ring 6. For example, a raised elastic coating layer 12e may be formed as in the fifth embodiment of FIG. Then, the elastic rings 12a to 12d and the elastic coating layer 12e are clamped between the front end surface 10 of the chuck cylinder portion 1a and the inner end surface 11 of the thrust ring 6 in the tightened state of the tightening nut 4. To set the dimensions.

According to the above configuration, when the entire chuck portion having the tool 8 is rotated to perform cutting, if coolant is supplied from the machine tool (not shown) side to the liquid guide passage 9 of the chuck body 1, The coolant flows into the split grooves 5a and 5b of the taper collet 3, and is jetted forward along the tool 8 from the open front end of the split groove 5a as shown by an arrow A in FIG. 3 to wet the tool 8 and the cutting portion. Cooling. However, since the annular seal layer 12 is interposed between the front end surface 10 of the chuck cylinder portion 1a and the inner end surface 11 of the thrust ring 6, the interface S1 between the tightening nut 4 and the thrust ring 6 and the tightening The coolant does not enter the threaded interface S2 between the nut 4 and the chuck cylinder portion 1A, and no leakage occurs from both interfaces S1 and S2. Therefore, the entire amount of the supplied coolant contributes to the cooling of the tool 8 and the cutting part, and the high cooling efficiency improves the high-speed cutting performance, and because the coolant is not wasted, the machining cost is low and the coolant is scattered. Since there is no risk of soiling the surrounding area, a good working environment can be secured, damage due to dirt on peripheral equipment can be avoided, and the lubricating function between the nut body 4a of the tightening nut 4 and the thrust ring 6 is also maintained well. To be done.

[0013]

[Effect of device]

 According to the present invention, as a collet chuck for fixing a tool to the chuck body through the taper collet and the tightening nut, when the coolant is drawn from the front end of the split groove of the taper collet and is subjected to cutting, There is no useless leakage, the entire amount of supplied coolant contributes to the cooling of tools and cutting parts, high cooling efficiency improves high-speed cutting performance, and since there is no waste of coolant, the processing cost is low and it is economical. In addition, since there is no risk of the coolant splashing and contaminating the surrounding area, a good working environment is ensured, failures due to dirt on peripheral equipment can be avoided, and a lubricating function between the nut body of the tightening nut and the thrust ring is provided. Goods that can be maintained well are provided.

[Brief description of drawings]

FIG. 1 is a front view of a collet chuck to which the present invention is applied.

FIG. 2 is a cross-sectional arrow view taken along the line II of FIG.

FIG. 3 is a sectional view taken along line II-II of FIG.

FIG. 4 is an enlarged view of a portion of the collet chuck according to the first embodiment of the present invention, which corresponds to a portion within a virtual circle O of FIG.

FIG. 5 is an enlarged view of the collet chuck of the second embodiment.

FIG. 6 is an enlarged view of the collet chuck of the third embodiment.

FIG. 7 is an enlarged view of the same as the collet chuck of the fourth embodiment.

FIG. 8 is an enlarged view of the collet chuck of the fifth embodiment.

[Explanation of symbols]

 1 Chuck body 1a Front part 2 Tapered hole 3 Tapered collet 4 Tightening nut 4a Nut body 5a Split groove open to the front end 5b Split groove open to the rear end 6 Thrust ring 7 Ball bearing 8 Tool 9 Coolant guide passage 10 Front end surface 11 Rear end face 12 Annular seal layer 12a Elastic ring (annular seal layer) 12b Elastic ring (annular seal layer) 12c Elastic ring (annular seal layer) 12d Elastic ring (annular seal layer) 12e Elastic coating layer 13a Screw part 13b Screw part

Claims (1)

[Scope of utility model registration request] 1. A collet chuck in which a tool is inserted into a taper hole of a chuck body via a taper collet, and the tool is fixed by tightening a tightening nut that is externally fitted and screwed to the front portion of the chuck body. A coolant liquid guide path communicating with the tapered hole is provided inside the main body,
A collet characterized in that an annular seal layer made of an elastic material is interposed between the front end surface of the chuck cylinder portion and the inner end surface of the thrust ring rotatably fitted to the inner circumference of the tightening nut. Chuck.