KR0177144B1 - Tool exchange device for a machine tool - Google Patents

Abstract

None.

Description

Drive mechanism of tool change arm

1 is a partial cross-sectional view of a swing arm drive mechanism as one embodiment of a drive mechanism of a tool changer arm of the present invention.

2 is a perspective view of a machining center equipped with this drive mechanism.

3 is a partial cross-sectional view.

4 is a view of the main part of the slewing rock from below.

5 is a vertical cross-sectional view of the bilimate.

6 is a configuration diagram showing the tip of the rock shaft.

7 is a cross-sectional view taken along line X-X in FIG.

8 is a timing chart centering on the operation of the swivel rock.

* Explanation of symbols for main parts of the drawings

16: Finger Pair 21-24: Cam

25: hollow spindle 29: rotating member

31: arm axial 34: segment gear

35: rocker

The present invention relates to a drive mechanism of a tool change arm, and more particularly, to a drive mechanism of a tool change arm for exchanging a tool between a main shaft of a machine tool and a tool magazine.

2. Description of the Related Art A tool change arm capable of exchanging a tool between a main shaft of a machine tool and a tool magazine is known. As one of them, a plurality of finger pairs capable of holding a tool on a main body and a finger capable of opening and closing the finger pair Some actuators for opening and closing are installed (Japanese Patent Laid-Open No. 63 (1988) -123646). The finger opening and closing actuator is, for example, using a rack and pinion, and is operated with the finger pair open from the closed state to hold the tool mounted on the spindle and the tool supported by the tool magazine with both finger pairs, respectively. By turning around the axis of the main body, the tools mounted on the main shaft and the tool magazine are replaced.

The tool change arm is pivoted by the rotation of a hollow shaft (hollow shaft) fixed to the main body, and moves through the hollow shaft to reciprocally rotate independently of the hollow shaft (rear shaft shaft). The finger opening / closing actuator was operated and driven.

In such a drive mechanism of a tool changer arm having a hollow shaft and a through shaft, the following two reasons: (1) the drive member for rotating the through shaft is provided on an extension line of the end opposite to the tool change arm side of the through shaft. Since the size of the direction of the coaxial shaft becomes larger by the shape of (2), and (2) the member that supports the hollow shaft separately from the through shaft, there is a problem that the whole of the machine tool is enlarged.

That is, as shown in FIG. 1 of Unexamined-Japanese-Patent No. 63-123646, the pinion is provided in the extension line of the edge part on the opposite side to the pivot rock side of a rotation rod. The rack, which is moved according to the planar groove cam and reciprocated, engages with the pinion, and the rotation rod is configured to regulate the rotation position. Therefore, there is a drawback that the size of the drive member (planar groove cam, rack) and the rotating rod in the axial direction is increased.

An object of the present invention is to provide a drive mechanism of a tool changer arm capable of solving the above problems and making the machine tool compact.

The drive mechanism of the tool changer arm of the present invention which achieves the above object comprises a tool changer arm having a finger opening and closing actuator capable of opening and closing a finger pair for holding a tool for a machine tool, and a main body of the tool changer arm. And a hollow shaft for rotating the tool changer arm reciprocating along one axis and rotating around the axis, and being inserted into the hollow spindle, and actuating the actuator in accordance with the actuator. A drive shaft of a tool changer arm comprising an arm central shaft and a rotating member rotatably mounted to the box body and coupled to the arm central shaft, wherein the hollow shaft is located near the end of the side on which the tool change arm is fixed. The shaft and the reciprocating movement in the axial direction by the inner peripheral surface of the hollow hole formed in the rotating member on the other end side and the shaft It is possible to support the rotation of the circumference, and at the same time between the box body and the support of the rotating member is provided with a hollow spindle drive means for imparting the reciprocating movement in the axial direction and the rotation around the axis, the rotation The member comprises a rotating member driving means for reciprocating the rotating member vehicle body around the axis at the side of the rotating member and simultaneously operating the female central shaft.

The hollow shaft is supported by the inner circumferential surface of the box body and the rotating member so as to enable rotation in the axial direction and the axial direction, and the two movements are performed by the hollow spindle driving means provided between the support parts. The tool change arm fixed to the hollow spindle carries out axial reciprocation or pivoting in accordance with these two motions. The tool change arm exchanges the tool between the spindle and the tool magazine by this action.

On the other hand, the arm central shaft may be engaged with or detached from the finger opening / closing actuator which reciprocates in conjunction with the hollow main shaft in accordance with the axial reciprocating movement of the moving hollow spindle independently of the arm central shaft. When engaged, the arm central shaft operates by receiving the movement of the coupled rotating member, that is, the reciprocating rotation around the axis by the action of the rotating member driving means, and drives the finger opening and closing actuator in the engaged state.

By this operation, the finger is opened and closed, and the tool of the spindle or the tool magazine is held or released.

Along with the holding and releasing of the tool by such a finger, a series of movements such as axial reciprocation of the tool changer and rotation around the axis are interlocked, thereby exchanging the tool between the main shaft and the tool magazine.

If the actuator has a hollow camshaft having a hollow portion, and the tip of the arm axial shaft is a guide portion, a slide portion, and a engaging portion, and the guide portion is always inserted into the hollow portion of the hollow camshaft, the arm axial shaft and hollow In the engagement with the camshaft, the guide portion engages with the guide and the slide portion enables smooth relative access to the engagement, so that the arm middle shaft and the hollow camshaft are securely engaged.

EMBODIMENT OF THE INVENTION In order to make clear the structure and operation | movement of this invention demonstrated above, the Example of the drive mechanism of the tool change arm of this invention is described next.

1 is a partial cross-sectional view of a swing arm drive mechanism as one embodiment of a drive mechanism of a tool change arm of the present invention, FIG. 2 is a perspective view showing a machining center to which the drive mechanism is mounted, and FIG. 3 is a partial cross-sectional view thereof.

First, the entire machining center on which the swing rock drive mechanism of the present embodiment is mounted will be described schematically with reference to FIG. 2 mainly.

As shown in FIG. 2, the machining center 3 is supported by the column 2 fixed to the base 1 in the machining center. The headstock 3 is guided to the linear guide 4 and moved up and down by the Z-axis feed motor 5 and the feed screw 6. The base 7 is further provided with a table 7. The table 7 is movable in the horizontal plane direction.

The spindle shaft 3 is equipped with a spindle motor 8, a spindle 9, and a rotary tool magazine 10. Since the spindle 9 and the tool magazine 10 are the same as those disclosed in Japanese Patent Application Laid-Open No. 63 (1988) -123646, the configuration thereof will be briefly described (the description of the spindle 9 is shown in FIG. 3). Reference). The main shaft 9 is connected to the tool mounting portion 11 capable of mounting and detaching the tool T and the tool mounting portion 11 through the drawbar 12 and pushed down to release the tool T. A tool release pin 13 is provided. The tool magazine 10 supports the tool T so that the tool T can be mounted and detached, and a plurality of support feet which are usually in a horizontal posture are provided at the periphery of the turntable. Only the lowermost support foot is rotated 90 degrees downward to assume a vertical position, and the swing arm A is in a state where tools can be changed. The selection of the tool T (positioning at the lowest position) is performed by the rotation of the magazine motor 14.

The spindle arm 3 is further equipped with a swing arm drive mechanism of the present embodiment for driving the swing arm A between the tool magazine 10 and the spindle 9.

Slewing rock (tool changing arm) A is composed of a main shaft (9) and a main shaft (16), a pair of fingers (17) arranged in two pairs so as to extend outward from the main body 16 and open and close. The tool T mounted on the tool magazine 10 is gripped by a pair of fingers 17 and exchanged by turning the tool change arm main body 16. The detailed structure of such a turning rock A is demonstrated using FIG. 4, FIG. 5 prior to the detailed description of the whole turning rock drive mechanism of this embodiment.

4 is a view of the main part of the slewing rock from below, and FIG. 5 is a vertical sectional view of the slewing rock. As shown in both figures, the arm body 16 of the turning rock A has a point symmetrical shape with respect to the center hole, and the hollow cam shaft 51 rotates independently of the arm body 16 through the bush B in the center hole. (Corresponding to an operating body for opening / closing a finger to the pivot arm A).

The hollow camshaft 51 is integrally provided with the cam part 51a extended in the horizontal direction near the center part of the perpendicular direction. A space S is mounted between the cam portion 5a and the bush B. FIG. The cam portion 51a has a shape in which two circular symmetric positions are cut out when viewed from below (see FIG. 4). The two cut parts 51b are the same shape. As shown in the cross section of the hollow portion 51c of the hollow camshaft 51, the hollow portion 51c has a groove shape (hollow groove).

On the upper surface of the arm body 16, two sets of two through holes 52 and 53 (see FIG. 5) are formed symmetrically with respect to the hollow camshaft 51. FIG. Two pairs of finger pairs 17 having the same configuration are supported by the arm body 16 so that the bolt 54 and the nut 55 can be rotated by using the through holes 52 and 53 of each pair.

The finger FA on the side close to the center camshaft 51 of each pair of finger pairs 17 extends outward from the cylindrical portion 17a through which the bolt 54 is inserted and from the outside of the arm body 16 to be held click G at the tip. A finger main body 17b having a recess, a passive part 17c extending in a substantially opposite direction from the finger main body 17b from the cylindrical part 17a, and contacting the cam part 51a, and protruding substantially perpendicularly to these. The protrusion 17d is formed integrally. The other finger FB is approximately symmetrical with the finger FA. However, the point where the passive counterpart 17x corresponding to the passive part 17c is slightly smaller than that of the passive part 17c, and the protruding part (hereinafter referred to as the engaging part) 17y corresponding to the protruding part 17d is the protruding part. It is somewhat different from (17d).

Each finger FA, FB is inserted into the cylindrical part 17a, and the end part of the bolt 54 passed through is supported by the arm main body 16 with the nut 55, and is parallel to the axis line of the hollow camshaft 51 of the turning arm A. In the state rotatable about one axis, the protrusion 17d and the engaging portion 17y are opposed to each other, and the passive portion 17c of the finger FA is provided in the cutout portion 51b. . A bush 56 is inserted between the inner surface of the cylindrical portion 17a and the outer surface of the bolt 54, and the raceway 57 is sandwiched between the arm body 16 and the upper surface of the cylindrical portion 17a.

A spring (compression spring) 58 is attached to the arm body 16 as a spring holder 59 so as to be located between the passive portion 17c and the passive counter portion 17x of each finger pair 17. The spring 58 exerts a force in the opening direction (outward direction) of opening the passive part 17c and the passive counterpart 17x. For this reason, the force is applied in the direction which the both-finger body parts 17b of the finger pair 17 close with the cylindrical part 17a fixed as a support point. However, the finger FA is in a state where the passive part 17c contacts the cam part 51a and does not close to a certain degree or more. On the other hand, the finger FB is also restrained from being closed for a certain degree because the engaging portion 17y is engaged with the protrusion 17D of the finger FA.

When the passive portion 17c is pressed against the turning force of the spring 58, the finger FA rotates in the opening direction with the cylindrical portion 17a as a supporting point, and the engaging portion 17x of the finger FB also has the protrusion 17d. Rotates toward the open side because it is pressed. The opening of the finger pair 17 is performed by applying a pressing force against the passive portion 17b by rotating the cam portion 51a at a predetermined angle in the direction of the arrow N around the central axis.

In order to prevent intrusion of the cutting powder or the like, the turning rock A is provided with a central axis pressing body 62 and an arm body pressing body 63 on the lower surface of the arm body 16 as shown in FIG.

The pivotal rock drive mechanism of the present embodiment for driving the pivotal rock A having the above-described configuration will be described.

As shown in FIG. 1, the swing arm drive mechanism of this embodiment has a tool change motor (hereinafter referred to as an ATC motor) 15 as a drive source. The tool change drive shaft (hereinafter referred to as the ATC drive shaft) 18 coupled to the ATC motor 15 is disposed in the vertical direction and rotates on the main shaft 3 by the bearings 19 and 20. It is so supported. Four cams 21, 22, 23, and 24 are provided on the ATC drive shaft 18.

On the other hand, on the side of the ATC drive shaft 18, the hollow spindle 25 having the spline 25a at the lower cut portion and the caller 25b at the lowermost end is disposed in the vertical direction. The hollow spindle 25 penetrates through the through hole 3a of the spindle head (box) 3 together with the bearing member 26 surrounding the lower end thereof, and is surrounded by the bush 27 around the central axis. Rotation and the reciprocating movement along the axis is supported. Moreover, the hollow member 25 penetrates the through-hole 3b of the headstock 3 with the bearing member 28 which surrounds the upper end part, and between this bearing member 28 and the hollow spindle 25 is carried out. The rotating member 29 and the bush 30 are rotatably mounted.

This rotating member 29 is a substantially cylindrical member, and the operation in the vertical direction is restricted. An upper portion of the hollow spindle 25 having a diameter smaller than the diameter of the center hole is inserted into a lower portion of the center hole of the rotating member 29. The upper part of the hollow hole of the rotating member 29 is smaller in diameter than the lower part thereof, and the upper end of the female central shaft 31 penetrating through the hollow spindle 25 uses keys 32 and bolts 33. It is inserted and fixed.

A gear 29a is formed on the outer circumference of the lower end of the rotating member 29. The gear 29a is meshed with the segment gear 34 provided on the side of the gear 29a. The swing gear 35 (sliding part) is fixed to this segment gear 34, and this follows the cam 24. As shown in FIG. Therefore, the rotating member 29 also operates as described later by the cam 24. Further, since the hollow spindle 25 between the inner circumferential surface of the rotating member 29 and the outer circumferential surface of the arm central shaft 31 is not fixed to both the 29 and 31, the rotating member 29 and the arm central shaft 31 and Exercise independently.

The hollow shaft 25 is reciprocated in the vertical direction by moving the cylindrical member 36 having the circumferential groove fixed in the vertical center thereof in the vertical direction. In the hollow spindle 25, the spline 25a below the hollow spindle 25 is surrounded by the spline minor shaft 37. In addition, the spline shaft 37 has a longitudinal roller 38 as a follower of the cam 21 on the upper and lower surfaces of the collar portion 37a formed on the outer circumference of the spline shaft 37. The lowest colo 25b of the hollow spindle 25 is screwed to the periphery of the hollow camshaft 51 in the arm body 16 of the turning arm A. As shown in FIG. Therefore, the hollow spindle 25 and the swivel rock main body 16 operate together. However, since the hollow spindle 25 and the hollow camshaft 51 are not fixed, they do not work together.

As shown in FIG. 6, the lower end of the arm axial shaft 31 which penetrates inside the hollow spindle 25 is formed as three different shape parts extended in a perpendicular direction.

The lowermost part of the shape part is a thin round part 31a. The central part on the round bar part 31a is the conical part 31b enclosed by the two inclined planes and the cylindrical peripheral surface which inclined so that the thickness of the center part might become narrow toward the round bar part 31a side. The upper part on the conical part 31b is the parallel surface part 31c enclosed by the two parallel planes and the cylindrical peripheral surface parallel to each other in the axis line of the arm center axis | shaft 31. As shown in FIG. The diameter of the round bar part 31a is considerably smaller than the groove width of the hollow groove of the hollow part 51C of the hollow cam shaft 51 of the turning arm A, and the parallel surface part 31C has a shape fitted with the hollow groove.

The hollow cam groove 51 of the turning arm A may approach or move away from the hollow spindle 25 and the turning arm A fixed to the hollow spindle 25 with respect to the arm central shaft 31 having such a tip.

The arm axial shaft 31 supports the round bar portion 31a at the tip of the arm axial shaft 31 in the hollow groove of the hollow portion 51b in the hollow cam shaft 51 of the pivot arm A even when it is as far away from the pivot arm A as possible. It is. Then, when the arm axial shaft 31 and the turning arm A approach, the conical portion 31b slides the hollow groove of the hollow camshaft 51 for a while, and then the parallel surface portion 31c is fitted into the hollow groove and engaged.

That is, the round bar part 31a functions as a quantum proximity guide first until the arm center axis | shaft 31 and the parallel surface part 31c approach and fit, and then the conical part 31b becomes a slide part, and the parallel surface part 31c is carried out. To guide the hollow camshaft (51). Therefore, the fitting between the arm center shaft 31 and the hollow cam shaft 51 of the turning arm A is always performed reliably.

As mentioned above, since the whole structure of the swivel drive mechanism of this embodiment became clear, the function of this drive mechanism is demonstrated with reference to the structure of the four cams 21-24 arrange | positioned at the ATC shaft 18. As shown in FIG.

The swing rock drive mechanism of the present embodiment pivots the swing rock A in the horizontal direction. This is for exchanging the tool T of the main shaft 9 and the tool magazine 10. Related to this operation is a parallel cam 21 positioned between the upper machine frame 28 and the lower machine frame 26 and fixed to the lowest position of the ATC drive shaft 18. The operation by this is the same as the counterpart of the apparatus disclosed in Japanese Patent Laid-Open No. 63 (1988) -123646, and will be briefly described (the same applies to the cams 22 and 23 described later). The parallel cam 21 is a composite cam composed of two plate cams, which are in contact with the terminating roller 38 as a follower provided on the spline shaft 37. Based on this configuration, the spline subshaft 37, the hollow spindle 25 splined thereto and the pivoting rock A fixed to the lower end thereof rotate 180 degrees while the ATC drive shaft 18 is rotated once. do.

In addition, the swing arm drive mechanism of the present embodiment reciprocates the swing arm A in the axial direction (vertical direction) of the hollow spindle 25. This is for separating or mounting the tool T from the spindle 9 or the tool magazine 10. Related to this operation is the first cylindrical groove cam 23 on the upper surface of the cylindrical member 39 fixed to the ATC drive shaft 18 located between the upper machine frame 28 and the lower machine frame 26. A contactor 41 provided at the distal end of the swing lever 40 engaged with the first cylindrical groove cam 23 is engaged with the circumferential groove of the circumferential member 36 outside the hollow shaft 25. Based on this structure, the ATC drive shaft 18 reciprocates once in the axial direction the pivotal arm A fixed to the hollow spindle 25 and the hollow spindle 25 during one rotation.

In addition, the swing rock drive mechanism of the present embodiment opens and closes the finger pair 17 provided on the main body of the swing rock A. FIG. Related to the operation is the flat groove cam 24 on the upper surface of the cylindrical member 30 fixed to the ATC drive shaft 18. 7 is a cross-sectional view taken along line X-X in FIG.

As shown, the groove shape of the flat groove cam 24 is a closed ring shape, and the small diameter part 24b of the large diameter part 24a of the circular arc centered around the cam rotation axis, and the connection part 24c which connects them are shown. Have The pair of fingers 17 is in a closed state and an open state depending on where the rocker 35 (slide) rotates against the large diameter portion 24a, the small diameter portion 24b, and the soft portion 24c of the planar groove cam 24. , Or the opening and closing movement state (this detailed operation will be described later).

The second cylindrical groove cam 22 formed below the main surface of the cylindrical member 39 outside the ATC drive shaft 18 functions as follows (see FIG. 3). When the second cylindrical groove cam 22 rotates, the rocking member 42 swings in accordance with this, and the tool release pin 13 connected to the drawbar 12 of the tool mounting and detachment device of the spindle 9 is rotated. Press down As a result, the tool T is set in the tool mounting part 11 of the main shaft 9, and it can be made into this state.

The pivotal rock drive mechanism of the present embodiment has the functions described above, and how each of these functions is related will be described with reference to FIG. 8 is a timing chart showing the operation of the turning rock A. FIG.

When the tool change is performed, the main shaft 9 stops at the correct position, and when it is confirmed that the main shaft has stopped, the ATC drive shaft 18 immediately starts to rotate. In addition, when the ATC drive shaft 18 starts to rotate, the pivot arm A which is movable up and down is at the top dead center, and the hollow cam shaft 51 of the arm middle shaft 31 and the pivot arm A is fitted. have. And the cam part 51a around the outer side of the hollow camshaft 51 presses the passive part 17c of the finger FA, and makes the finger FA open in response to the elastic force of the spring 58. As shown in FIG. The finger FB is held open against the elastic force of the spring 58, similarly to the finger FA, because the engaging portion 17y of the finger FB is pressed by the protrusion 17d of the finger FA. That is, the finger pair 17 of two degrees is in the open state.

The tool T with the main shaft 9 clamped between the pair of finger grips G of the pair of finger pairs 17 in the open state is connected to the tool magazine 10 between the grip group G of the other foot of the pair of finger pairs 17. The clamped tool T is fitted.

When the ATC drive shaft 18 rotates to reach a rotation angle of 12 ° as shown in FIG. 8, the oscillator 35 leaves the small diameter portion 24b of the flat groove cam 24 and reaches the connecting portion 24c. Begin to swing. Thereby, the segment gear 34, the rotating member 29, and the arm shaft 31 which follow the oscillator 35 also begin to rotate. In addition, the hollow cam shaft 51 of the turning arm A fitted to the arm central shaft 31 also starts to rotate by the rotation of the arm central shaft 31. Then, the cam part 51a of the outer periphery of the hollow camshaft 51 starts to rotate in the direction of arrow M of FIG. 4, ie, the direction which reduces the pressing force to finger FA. Therefore, the finger FA starts to close by the elastic force of the spring 58. The finger FB receives the motion from the fitting portion 17y at the same time and starts to close under the elastic force of the spring 58. When the ATC drive shaft 18 rotates by 50 degrees and the oscillator 35 reaches the large diameter portion 24a of the flat groove cam 24, the oscillator 35 enters a stopped state. At that time, the dark central shaft 31 enters the stop state in the state which rotated 18 degrees from the initial state. The cam portion 51a of the hollow camshaft 51, which enters the stationary state while being rotated 18 degrees with the arm middle shaft 31, does not apply the pressing force for opening the finger to the finger FA in this stationary state. Therefore, the pair of finger pairs 17 is in the closed state by the spring 8. As a result, two pairs of finger pairs 17 hold the tool T of the main shaft 9 and the tool magazine 10, respectively.

While the finger pair 17 is in the closed state from the open state, precisely when the ATC drive shaft 18 is rotated 25 °, the tool release pin 13 starts to descend by the action of the second cylindrical groove cam 22. do. And when the ATC drive shaft 18 rotates 75 degrees, the tool T will be in the state (unclamped state) completely disengaged from the main shaft 9.

While turning from the clamp state of the tool T to the unclamp state, when the ATC drive shaft 18 is rotated by 65 degrees, the turning arm A starts to descend by the first cylindrical groove cam 23. Then, the turning arm A reaches the bottom dead center when the ATC drive shaft 18 rotates 125 degrees. In addition, when the ATC drive shaft 18 is near 100 °, the arm center shaft 310 is not fitted to the hollow cam shaft 51 of the swing arm A.

The tool T is separated and removed from the tool magazine 10 while the turning arm A reaches the bottom dead center from the top dead center. In the meantime, when the ATC drive shaft 18 is rotated 100 degrees, the turning arm A starts to rotate by the action of the parallel cam 21 or the like. Then, when the ATC drive shaft 18 rotates 280 °, the turning is finished. This operation replaces the arrangement of the two tools T set on the main shaft 9 and the tool magazine 10.

During turning of the turning arm A, exactly when the ATC drive shaft 18 rotates 235 degrees, the turning arm A starts to rise from a bottom dead center. And when ATC drive shaft 18 rotates 295 degrees, it reaches top dead center. At this time, the tool T is inserted into the tool magazine 10 and it is clamped. On the other hand, the tool is inserted into the main shaft 9, but is not yet clamped. In addition, the ATC drive shaft 18 is engaged with the arm center shaft 31 and the hollow cam shaft 51 of the swing arm A around 270 °. At this time, as described above, the tip of the arm central shaft 31 is a portion for performing the guide of the guide to the hollow portion 51c of the hollow camshaft 51, the portion sliding to the hollow portion 51c, and the hollow portion ( Since the part fitted into 51c is provided, the hollow cam shaft 51 and the arm center shaft 31 are reliably fitted.

While the turning arm A proceeds from the top dead center to the top dead center, exactly when the ATC drive shaft 18 rotates 285 °, the release pin 13 starts to rise by the action of the second cylindrical groove cam 22. . Then, when the ATC drive shaft 18 is rotated 335 degrees, the release pin 13 returns to the initial position, and the tool T is completely clamped to the main shaft 9.

When the ATC drive shaft 18 is rotated 310 degrees precisely while the tool T is clamped to the main shaft 9 from the unclamped state, the swinger 35 separates the large diameter portion 24a of the flat groove cam 24, The swinging motion is started again by engaging the connecting portion 24c. In this way, the arm axial shaft 31 starts to rotate opposite to the rotation. By the rotation of the arm center shaft 31, the hollow cam shaft 51 of the turning arm A fitted to the arm center shaft 31 also starts to rotate in reverse. Then, the cam portion 51a of the hollow camshaft 51 outer projection starts to rotate in the direction of the fourth arrow N, that is, in the direction of pushing the passive portion 17c of the finger FA. As a result, the finger FA starts to open. The finger FB also starts to open by receiving the motion through the protrusion 17b at the alignment portion 17y. Thus, the pair of finger pairs 17 is opened.

When the ATC drive shaft 18 rotates 348 degrees and the oscillator 35 reaches the small diameter portion 24b of the flat groove cam 24, the oscillator 5 enters a stopped state. At that time, the dark central shaft 31 returns to the same stopped state as the initial stage. The cam part 51a of the outer projection of the hollow camshaft 51 also returns to an initial stop state along with this arm center shaft 31, and the manual part 17c of the finger FA is pressed, and the finger FA is opened. The finger FB is also opened by receiving the operation of the finger FA by the engaging portion 17y. As a result, the finger pair 17 opens the main shaft 9 and the tool T of the tool magazine 10.

The pivotal rock drive mechanism of the present embodiment described above has the following advantages.

A planar cam 24, a rocker 35, and a segment gear 34 for rotating the rotary member 29 to operate the arm shaft 31 fixed thereto are provided on the side of the rotary member 29. Therefore, the height of a machining center can be suppressed and the whole structure can be made compact.

Since the rotating member 29 may also play a role of stably supporting the hollow spindle 25, the movement of the hollow spindle 25 may be stably progressed. That is, the hollow spindle 25 is easy to be shaken by the pivoting motion by the parallel cam 21 or the vertical movement by the cylindrical groove cam 23 in spite of the support by the spindle 3 on the lower side, but the rotation is easy. Since the member 29 supports the hollow spindle 25 at its inner circumferential surface, the hollow spindle 25 is reliably kept vertical.

Thus, since the rotating member 29 also serves as the drive member of the arm center shaft 31, and the support member of a hollow spindle, it contributes also to the compaction of the whole structure of a machining center.

Since the tip of the arm axial shaft 31 is formed as a guide portion (round bar portion 31a), a slide portion (conical portion 31b), and a engagement portion (parallel surface portion 31c) in order from the tip, the arm axial axis 31 and the engagement portion are approached. The guide section functions first as a guide in proximity to each other until it is fitted, and then the slide section performs an induction function. Therefore, the arm center shaft 31 and the hollow cam shaft 51 of the turning arm A are always securely fitted and performed in the same state. Therefore, the operation of the finger pair 17 is assured.

As mentioned above, although the Example of this invention was described, this invention is not limited to this Example at all, For example, the tool change arm disclosed by Unexamined-Japanese-Patent No. 63 (1988) -123646 instead of the said slewing rock. It goes without saying that the present invention can be implemented in various aspects within the scope of not departing from the gist of the present invention, such as a configuration using the present invention.

As mentioned above, according to the drive mechanism of the tool change arm of this invention, since the drive member which operates an arm center shaft is provided in the side of an arm center shaft rather than the extension line of an arm center shaft, the whole structure of a machine tool can be made compact. . In addition, since the rotating member can serve to stably support the hollow spindle, which is easily shaken by the operation of the hollow shaft driving means, the movement of the hollow spindle and the operation of the entire machine tool proceed smoothly.

In this way, the rotary member also serves as the drive member of the arm central shaft and the support member of the hollow spindle, thus contributing to the compactness of the overall configuration of the machine tool.

Claims (2)

A tool change arm equipped with a finger open / close actuator for opening and closing a finger pair for holding a tool for a machine tool, and a main body of the tool change arm fixed at an end thereof, reciprocating the tool change arm along one axis. A hollow shaft which is moved and rotates around this axis, a female central shaft which is inserted into the hollow shaft and which can be engaged with the actuator to operate the actuator, and is rotatable to a box body A drive body of a tool changer arm provided with a rotating member coupled to the arm pivot, wherein the hollow shaft is formed by the box body near the end of the side on which the tool changer arm is fixed, and on the other end side; The inner circumferential surface of the hollow hole formed in the rotating member enables the reciprocating movement in the axial direction and the rotation around this axis to be supported. A hollow shaft drive means for imparting reciprocating movement in the axial direction with respect to the hollow shaft itself and rotation around the axis between the box body and the rotating member, wherein the rotating member is a rotating member on the side of the rotating member. And a rotating member drive means for reciprocating itself about the axis and operating the arm pivot. 2. The actuator according to claim 1, wherein the actuator has a hollow camshaft, and in the arm axial shaft, an end portion of the side engaged with the hollow camshaft is formed as a guide portion, a slide portion, and a engagement portion with respect to the hollow camshaft in order from a front end side. And driving the tool exchange arm which is supported with the guide portion of the arm central shaft inserted into the hollow portion of the hollow cam shaft, even when the arm central shaft and the hollow cam shaft fall as far as possible by the reciprocating movement in the axial direction of the hollow spindle. Instrument.

Images