JP4205970B2 - Collet chuck device - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a collet chuck device used for machine tools such as NC benders, automatic lathes, and milling machines.
[0002]
[Prior art]
For example, a collet chuck is known from Patent Document 1 below as a workpiece gripping device used in machine tools such as NC benders, automatic lathes, and milling machines.
[0003]
[Patent Document 1]
JP 2002-66815 A [Patent Document 2]
Japanese Patent Laid-Open No. 2000-158216
In this type of collet chuck, the tip of a cylindrical collet sleeve is usually formed in a split groove by forming a longitudinal groove, and a tapered surface is formed on the outer peripheral surface of the tip. The chuck sleeve is externally fitted, and a pressing taper surface is formed at the tip of the chuck sleeve. The chuck sleeve is moved with respect to the collet sleeve, and the taper surface of the collet is pressed by the pressing taper surface, thereby reducing the diameter of the collet sleeve, and this collet chuck operates to grip the inner workpiece. To do.
[0005]
[Problems to be solved by the invention]
However, this type of collet chuck is used in a machine tool such as an NC bender that performs very precise bending, so that the outer diameter of the workpiece is, for example, in order to grip the workpiece with a very strong gripping force. Even when the diameter is changed by 0.5 mm, an error occurs in the bending accuracy, so that it is necessary to replace it with another collet chuck having a size corresponding to the outer diameter of the workpiece. For this reason, each time the workpiece changes, the collet chuck is replaced by loosening many fixing screws, and the complicated work of tightening many fixing screws again to fix another collet chuck is forced. There was a problem that a lot of work man-hours and work time were required at the time of setup.
[0006]
Therefore, conventionally, a collet member that grips the workpiece is divided into a plurality of parts, and these collet members are engaged with the tip of the collet sleeve, and a tapered surface provided on the outer periphery of the collet member is formed on the outer side. A collet chuck device that presses against a pressing surface of a positioned pressing sleeve to reduce the diameter of these collet members has been proposed in Patent Document 2 and the like.
[0007]
However, even in a collet chuck device using this type of split collet member, various sizes of collet members are prepared corresponding to the size of the workpiece, and the outer diameter of the workpiece changes. In such a case, the collet member needs to be exchanged according to its size, and there is a problem that a large number of work steps and work time are required for the work.
[0008]
SUMMARY OF THE INVENTION The present invention solves the above-described problems, and can collide workpieces having different outer diameters with high accuracy and with a large gripping force, and can eliminate the collet chuck replacement operation. An object is to provide a chuck device.
[0010]
[Means for Solving the Problems]
In order to achieve the above object, a collet chuck device according to the present invention includes a base member fixed to the tip of a main shaft, a plurality of connecting rods that rotate together with the main shaft and are arranged to be movable in the axial direction with respect to the main shaft. An annular sliding body that is disposed in front of the base member, is fixed to the tip of the connecting rod and is movable in the axial direction, and is fitted inside the annular sliding body so as to be slidable in the axial direction and the diameter-reducing and expanding directions. At least three collet gripping members mounted, and radial sliding grooves are formed radially on the front portion of the base member so that the collet gripping members are fitted and slid radially. Inside, each collet gripping member is inserted to form an axial sliding groove that slides in the axial direction. Each axial sliding groove of the annular sliding body has a tapered surface, and the corresponding collet gripping member Inclined surface in contact with the tapered surface A sliding guide portion is formed on each side of each radial sliding groove of the base member in a radial direction, and is slidably fitted to the side portion of the collet gripping member so as to be slidable with the sliding guide portion. A guide portion is formed, a slide guide portion is formed along the tapered surface inside the axial slide groove in the annular slide body, and a sliding guide portion is fitted to the side portion of the collet gripping member. The moving guide portion is formed along an inclined surface .
[0012]
According to a second aspect of the present invention, there are eight collet gripping members, and eight radial sliding grooves are formed radially at equal intervals in the circumferential direction at the front of the base member. Can be formed radially at equal intervals in the circumferential direction by inserting eight collet gripping members and sliding them in the axial direction.
[0013]
[Action]
In the collet chuck device configured as described above, the plurality of connecting rods are moved back and forth in the axial direction with respect to the main shaft, and the annular sliding body is moved back and forth with respect to the base member. At this time, as the annular sliding body moves, the collet gripping member slidably fitted in the inner axial sliding groove receives a radial force from the inner tapered surface through the outer inclined surface. Each collet gripping member is moved in the radial direction while being held in the radial sliding groove of the base member in the annular sliding body. Accordingly, each collet gripping member moves in the diameter reducing direction or the diameter expanding direction, and operates to grip the workpiece inside the collet gripping member or release the gripping.
[0014]
In this way, at least three collet gripping members for gripping the workpiece slide in the axial direction as the annular sliding body moves back and forth, and guide to the sliding guide portion of the radial sliding groove of the base member. Because it moves in the radial direction, even if the outer diameter of the workpiece changes, each collet gripping member is moved according to the outer diameter to grip the workpiece powerfully and with high accuracy. Can do. Further, if the number of collet gripping members is set to eight and arranged at intervals of 45 degrees in the circumferential direction, even a relatively large-diameter workpiece can be strengthened by the eight collet gripping members. In addition, it can be gripped with high accuracy, and processing such as bending and cutting can be performed with high accuracy.
[0015]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, an embodiment of the present invention will be described with reference to the drawings. 1 is a perspective view of the collet chuck device, FIG. 2 is an enlarged perspective view of a collet gripping member 10 used therein, and FIG. 3 is an exploded perspective view of the collet gripping member 10 removed.
[0016]
The collet chuck device includes a base member 3 fixed to the front end of the main shaft 1 and a plurality of the collet chuck devices disposed at the front portion of the base member 3 and slidable in the axial direction with respect to the main shaft 1 and the base member 3. The sliding member 2 is slidably fitted into the annular sliding member 2 fixed to the tip of the connecting rod 4 and the radial sliding groove 31 formed radially at the front portion of the base member 3. A plurality of collet gripping members 10 that are slidably fitted into the inner axial sliding groove 22 and perform a gripping operation of the workpiece in accordance with the movement of the annular sliding body 2.
[0017]
The main shaft 1 is supported by a main shaft base (not shown) via a bearing, and is rotationally driven by a driving device. The base member 3 is fixed to the tip of the main shaft 1. As shown in FIG. 3, the base member 3 is formed in an approximately octagonal columnar shape, and has eight axial holes 33 at equal intervals in the circumferential direction in the vicinity of the outer peripheral portion thereof, that is, at an interval of 45 degrees. The connecting rod 4 is slidably inserted into each hole 33.
[0018]
Further, eight radial sliding grooves 31 are formed at intervals of 45 degrees in the circumferential direction at each side position of the octagonal base member 3 on the front surface of the base member 3. These radial sliding grooves 31 are formed by forming a wide groove portion slightly wider at the back of the substantially rectangular groove and providing a protrusion 32 in the radial direction as a sliding guide portion in front of the groove. The end portion (original portion) of the collet gripping member 10 is slidably fitted into the moving groove 31.
[0019]
As shown in FIGS. 3 and 6, the annular sliding body 2 positioned in front of the base member 3 is formed in a substantially octagonal column shape with a substantially circular opening 25 at the center, and an axial rod near the outer periphery thereof. Eight fixing holes 21 are formed, that is, at intervals of 45 degrees, and the tips of the connecting rods 4 are fitted into the rod fixing holes 21 and fixed by fixing screws or the like. Eight axial sliding grooves 22 are formed at intervals of 45 degrees on the inner side of the annular sliding body 2, that is, on the inner wall portion of the opening 25.
[0020]
These axial sliding grooves 22 are formed in the axial direction and in the radial direction, the grooves are formed with the same width in the axial direction, and in the radial direction, the depth of the groove gradually increases from the front part to the rear part. It is formed to be deep. That is, when viewed in a cross section along the axial direction, the eight axial sliding grooves 22 are formed in a substantially trapezoidal shape as shown in FIG. 6, and the tapered surface 24 is formed on the outer peripheral side, and the tapered surface. Reference numeral 24 denotes a structure in which the inclined surface 13 of the collet gripping member 10 contacts.
[0021]
Further, wide groove portions 23 are formed along the tapered surface 24 on both side inner walls of the axial sliding grooves 22, and protrusions 26 serving as sliding guide portions along the wide groove portions 23. Protrusively formed on the inside. Both sides of the collet gripping member 10 on the inclined surface 13 side can be fitted and slid in the wide groove portion 23, and the protruding portion 26 is slid along the inclined surface 13 of the collet gripping member 10. The first groove portion 14 serving as a moving guide portion is fitted and slidable.
[0022]
As shown in FIGS. 2, 4, and 5, the collet gripping member 10 that is fitted and fitted in each radial sliding groove 31 of the base member 3 and each axial sliding groove 22 of the annular sliding body 2 has a side surface. It is formed in a plate shape having a substantially trapezoidal view, an inclined surface 13 is formed on the upper surface, and an uneven gripping surface 16 is formed on the lower surface.
[0023]
That is, when viewed in a side view, the collet gripping member 10 has a short-side tip portion 11 at its tip portion, a long-side end portion 12 at its end portion (base portion), and the short-side tip portion 11. And the long side end portion 12 are connected to form an inclined surface 13, and the lower side thereof is connected to form an uneven gripping surface 16 parallel to the axial direction. The concavo-convex gripping surface 16 is a part that grips the workpiece, and fine concavo-convex portions are provided along the axial direction.
[0024]
Further, first side grooves 14 serving as sliding guide portions are formed along the inclined surface 13 on both side surfaces of the collet gripping member 10, and along the long side end portion 12 near the long side end portion 12. Second groove portions 15 serving as sliding guide portions are formed on both side surfaces. In this first groove portion 14, a ridge portion 26 on the side portion of the axial sliding groove 22 of the annular sliding body 2 is slidably fitted. Further, the protrusions 32 of the radial sliding grooves 31 of the base member 3 are fitted into the second groove 15 so as to be slidable in the radial direction.
[0025]
When the collet gripping member 10 is assembled to the collet chuck device having such a configuration, first, the eight collet gripping members 10 are respectively placed in the radial sliding grooves 31 on the front surface of the base member 3 and the long side end portion 12 of the collet gripping member 10 is inserted. The two groove portions 15 are fitted into the ridge portions 32 so as to be slidable. Then, the annular sliding body 2 is brought close to the front portion of the base member 3, and the eight collet gripping members 10 are fitted into the short side end portions 11 from the end side of the annular sliding body 2.
[0026]
As a result, each collet gripping member 10 has its inclined surface 13 in contact with the tapered surface 24 of the annular sliding body 2, and the protruding portion 26 of the annular sliding body 2 is slidably fitted into the first groove portion 14. And the front-end | tip part of the connecting rod 4 inserted in each hole 33 of the base member 3 is inserted in the rod fixing hole 21 of the cyclic | annular sliding body 2, and is fixed there with the fixing screw which is not shown in figure.
[0027]
Therefore, when the connecting rod 4 is moved in the axial direction with respect to the base member 3 in the direction of returning to the driving side, for example, the annular sliding body 2 moves in the axial direction as shown in FIGS. The member 10 receives an inward force from the tapered surface 24 of the annular sliding body 2 on the inclined surface 13 and moves inward, and the position of the gripping surface 16 of each collet gripping member 10 moves in the diameter-reducing direction. The object can be gripped.
[0028]
Further, when the connecting rod 4 is moved in the direction of pushing the connecting rod 4 toward the distal end side with respect to the base member 3, the annular sliding body 2 moves in the axial direction as shown in FIGS. 1 to 9, and at this time, each collet gripping member 10 The first groove portions 14 on both sides receive the force directed outward through the protrusions 26 on both sides of the annular sliding body 2 and move outward, and the positions of the gripping surfaces 16 of the collet gripping members 10 are in the diameter increasing direction. Then, the base member 3 moves outward along the radial sliding grooves 31 to release the workpiece.
[0029]
As shown in FIG. 7, the collet chuck device configured as described above is attached to the tip of the spindle 1 of a machine tool such as an NC bender and is used for gripping a workpiece. At the base portion of the main shaft 1, a sliding ring 5 having eight connecting rods 4 attached thereto is provided so as to be able to rotate together with the main shaft 1 and to be slidable in the axial direction. Is attached to the sliding ring 5 via a rolling bearing so as to be rotatable (to allow rotation of the main shaft 1). And the front-end | tip part of the opening / closing lever 6 is pivotally supported with respect to a fixed part, the extension part of the rotary joint 7 is connected with the intermediate part of the opening-and-closing lever 6 with a pin, and the opening-and-closing drive is carried out at the front-end | tip of the opening / closing lever 6 As the portion 8, a piston rod of a fluid pressure cylinder or the like is connected.
[0030]
When the work piece is gripped by the collet chuck device, first, the opening / closing drive unit 8 is driven to drive, and the sliding ring 5 and the connecting rod 4 are moved so as to be pushed to the right in FIG. As a result, the annular sliding body 2 moves forward as shown in FIG. 9, and at this time, the eight collet gripping members 10 in the annular sliding body 2 are moved from the protrusions 26 of the annular sliding body 2 to the first groove portion 14. The force in the outer direction is received through the base member 3, and the inside of the radial sliding groove 31 of the base member 3 is moved in the diameter increasing direction, so that the gripping inner diameter is increased.
[0031]
In this state, a workpiece (not shown) is put inside the collet gripping member 10 in the annular sliding body 2, and the opening / closing drive unit 8 is driven in the direction of the arrow in FIG. As a result, as shown in FIG. 7, the opening / closing lever 6 is rotated to the left, the sliding ring 5 and the connecting rod 4 are moved to the left in FIG. 7, and the annular sliding body 2 fixed to the tip of the connecting rod 4 is formed. The base member 3 moves so as to be pulled back.
[0032]
Accordingly, as shown in FIGS. 1 to 8, the annular slide body 2 moves to the base member 3 side, and at this time, the tapered surface 24 of the axial sliding groove 22 in the annular slide body 2 holds each collet. Each collet gripping member 10 moves in the diameter-reducing direction while being held in the radial sliding groove 31 of the base member 3 so that the inclined surface 13 of the member 10 is pushed inward. The workpiece is gripped strongly.
[0033]
As described above, the eight collet gripping members 10 that grip the workpiece slide in the axial direction as the annular sliding body 2 moves back and forth, and the ridges of the radial sliding grooves 31 of the base member 3. Since the outer diameter of the workpiece is changed, the collet gripping member 10 is moved in accordance with the outer diameter, so that the workpiece is powerfully and highly accurate. Can be gripped. Further, since the number of the collet gripping members 10 is eight and is arranged at intervals of 45 degrees in the circumferential direction, even if the workpiece has a relatively large diameter, the eight collet gripping members 10 are used. Therefore, it is possible to grip and powerfully perform high-precision processing such as bending and cutting.
[0034]
In addition, the relationship of the protrusion 32 which forms the sliding guide part of the radial sliding groove 31 of the base member 3 of the said embodiment, and the 2nd groove part 15 of the collet holding member 10 fitted to it may be reversed. Moreover, the relationship between the protrusion 26 forming the sliding guide portion of the axial sliding groove 22 of the annular sliding body 2 and the first groove portion 14 of the collet gripping member 10 fitted thereto may be reversed. In the above embodiment, the base member 3 is provided with the eight radial sliding grooves 31 and the eight collet gripping members 10 at intervals of 45 degrees in the circumferential direction. Is small, it is possible to use a minimum of three collet gripping members.
[0035]
【The invention's effect】
As described above, according to the collet chuck device of the present invention, at least three collet gripping members for gripping the workpiece slide in the axial direction as the annular sliding body moves back and forth, and the base member Therefore, even if the outer diameter of the workpiece changes, each collet gripping member is moved according to the outer diameter, and the workpiece is moved. The workpiece can be gripped strongly and with high accuracy. Therefore, it is not necessary to prepare collet members of various sizes corresponding to the size of the workpiece, and even if the outer diameter of the workpiece changes, without performing the collet member replacement work, You can start working immediately. Further, if the number of collet gripping members is set to eight and arranged at intervals of 45 degrees in the circumferential direction, even a relatively large-diameter workpiece can be strengthened by the eight collet gripping members. In addition, it can be gripped with high accuracy, and processing such as bending and cutting can be performed with high accuracy.
[Brief description of the drawings]
FIG. 1 is a perspective view of a collet chuck device showing an embodiment of the present invention.
FIG. 2 is a perspective view of eight collet gripping members.
FIG. 3 is an exploded perspective view of a collet chuck device excluding a collet gripping member.
FIG. 4 is a perspective view of a collet gripping member.
5A is a side view of a collet gripping member, FIG. 5B is a front view thereof, and FIG. 5C is a plan view thereof.
FIG. 6 is an enlarged cross-sectional view of an annular sliding body.
FIG. 7 is a plan view showing a mounting state of the collet chuck device.
FIG. 8 is a perspective view showing a usage state of the collet chuck device.
FIG. 9 is a perspective view showing a usage state of the collet chuck device.
[Explanation of symbols]
1-main shaft 2-annular sliding body 3-base member 4-connecting rod 10-collet gripping member 13-inclined surface 14-first groove portion 15-second groove portion 22-axial sliding groove 24-taper surface 26-projection Part 31-radial sliding groove 32-ridge part

Claims (2)

A base member fixed to the tip of the main shaft;
A plurality of connecting rods that rotate together with the main shaft and are axially movable with respect to the main shaft;
An annular sliding body disposed in front of the base member, fixed to the tip of the connecting rod, and movable in the axial direction;
At least three collet gripping members fitted inside the annular sliding body so as to be slidable in the axial direction, the reduced diameter direction, and the increased diameter direction;
With
A radial slide groove is formed radially in the front portion of the base member so that the collet gripping members are fitted and slid in the radial direction. The collet gripping members are fitted inside the annular slide body. An axial sliding groove that slides in the axial direction is formed ,
A taper surface is formed in each axial sliding groove of the annular sliding body, and an inclined surface in contact with the taper surface is formed on a corresponding surface of the collet gripping member, and each radial sliding groove of the base member A sliding guide portion is formed in a radial direction on the side of the collet gripping member, and a sliding guide portion is formed on the side portion of the collet gripping member so as to be slidably fitted with the sliding guide portion. A sliding guide portion is formed along the tapered surface inside the axial sliding groove in the moving body, and a sliding guide portion into which the sliding guide portion is fitted is inclined on the side portion of the collet gripping member. A collet chuck device characterized by being formed along the line .   Eight collet gripping members are arranged, eight radial sliding grooves are radially formed in the circumferential direction at equal intervals in the front portion of the base member, and each collet gripping member is provided inside the annular sliding body. 2. The collet chuck device according to claim 1, wherein eight axial sliding grooves which are inserted and slid in the axial direction are formed radially at equal intervals in the circumferential direction.

Images