JP2000084777A - Automatic tool exchanger - Google Patents

Abstract

PROBLEM TO BE SOLVED: To shorten the tool exchange time and to surely exchange a tool. SOLUTION: This automatic tool exchanger comprises a tool exchange arm 203; an arm driving mechanism part 201 holding the tool exchange arm 203 and executing the specific tool exchanging operation comprising the revolving motion and the linear motion; a driving motor 210 for driving the arm driving mechanism part 201; a fastening and releasing mechanism part 51 for fastening a tool 301 to a spindle by the fastening force by the elastic force of an elastic means, and releasing the engagement with the tool 301 by the action of the releasing force against the fastening force; a cam mechanism part 151 generating the releasing force to the fastening and releasing mechanism part 51 linked with the tool exchanging motion of the tool exchange arm 203, from the torque of the driving motor 210; and a releasing force transmitting mechanism part for transmitting the releasing force supplied from a cam mechanism part to the fastening and releasing mechanism part 51 through a specific transmission passage.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an automatic tool changer for changing a tool mounted on a main shaft of a machine tool such as a machining center.

[0002]

2. Description of the Related Art An automatic tool changer built in or attached to a machine tool such as a machining center includes, for example, a tool magazine for accommodating a plurality of tools, and a gripper for gripping a tool at both ends formed with a spindle of the machine tool. And a tool change arm for changing a tool between the tool changer and the tool magazine.
The tool change by the tool change arm is performed, for example, by turning the tool change arm between the tool moved to the predetermined standby position of the tool magazine and the main spindle positioned at the predetermined tool change position with respect to the tool change arm. The tool in the standby position and the tool mounted on the spindle are gripped, the tool change arm moves linearly, removes the tool mounted on the spindle, and the tool change arm pivots and linearly moves again, so that it is in the standby position. The new tool is mounted on the spindle.

[0003] In the automatic tool changer having the above configuration,
The tool mounted on the spindle is clamped by a clamp device provided in the spindle. The clamp device is provided, for example, in a mounting hole for mounting a tool formed in the axial direction of the main shaft, and is provided movably in the main shaft with an openable / closable chuck claw engaging with an end of the tool. It has a push rod for opening and closing the chuck jaws, and a spring for urging the push rods in the axial direction. The elastic force of the spring urges the push rods in a predetermined direction, so that the chuck jaws move the main shaft. The tool is engaged with one end of the tool mounted on the to clamp the tool. The tool clamped by the clamp device is unclamped by applying a force against the elastic force of the spring in the axial direction of the push rod to open the chuck jaws.

[0004]

In the prior art, the drive of the push rod for unclamping of the clamp device has been performed by, for example, providing a hydraulic cylinder device in the axial direction of the push rod. However, in the unclamping operation of the tool by the hydraulic cylinder device, the time required for the tool to be in the unclamped state is not constant because the response of the hydraulic cylinder device is relatively poor, and the like.
In many cases, tool unclamping is not completed within a predetermined time. If the unclamping of the tool mounted on the spindle is not completed, the tool change arm cannot remove the tool mounted on the spindle until the unclamping of the tool mounted on the spindle is completed. There was the disadvantage of longer time. In addition, if the time required to complete the unclamping of the tool mounted on the spindle is not constant, the turning and linear movement of the tool changing arm and the unclamping of the tool mounted on the spindle are required to shorten the tool changing time. When the operation is duplicated, the tool change arm may not be able to reliably remove the tool from the spindle.

SUMMARY OF THE INVENTION The present invention has been made in view of the above problems, and has as its object to provide an automatic tool changer capable of shortening a tool change time and reliably performing a tool change operation. And

[0006]

SUMMARY OF THE INVENTION According to the present invention, there is provided a tool changing arm having grips at both ends for holding a tool, the tool changing arm being held, and the tool changing arm having a predetermined rotation axis as a center. An arm drive mechanism for performing a predetermined tool change operation including a turning operation and a linear motion in the direction of the rotation axis; a drive motor provided in the arm drive mechanism for driving the arm drive mechanism; and the tool It is built into a main shaft movably provided to a predetermined tool gripping position with respect to the exchange arm, and engages with the tool by a fastening force due to elastic force of elastic means, fastens the tool to the main shaft, and reduces the fastening force. A fastening release mechanism for releasing engagement with the tool by the action of a resisting release force, and the fastening release mechanism cooperating with a predetermined tool changing operation of the tool changing arm from a rotational force of the drive motor. Has a cam mechanism for generating a release force, and a release force transmitting mechanism for transmitting a predetermined transmission path to said fastening releasing mechanism release force supplied from the cam mechanism portion for.

In the present invention, a rotational force is supplied to the cam mechanism from a drive motor that drives an arm drive mechanism for performing a predetermined tool changing operation of the tool changing arm. A release force is generated in association with a predetermined tool change operation of the tool change arm. This release force is transmitted from the cam mechanism to the fastening release mechanism through the release force transmission mechanism. As a result, the predetermined tool exchanging operation of the tool exchanging arm and the releasing operation of the fastening and releasing mechanism are reliably performed in cooperation with each other, and the releasing force output from the cam mechanism is transmitted to the fastening and releasing mechanism with good responsiveness. The time required for the release of the tool by the fastening and releasing mechanism is always constant, so that the tool exchange arm can smoothly extract the tool without waiting, and reliably perform the tool exchange operation.

The arm drive mechanism has a cam mechanism for defining a predetermined tool changing operation including a turning operation and a linear moving operation of the tool changing arm.

[0009]

Embodiments of the present invention will be described below with reference to the drawings. 1 and 2 are views showing an example of the configuration of a machining center to which the present invention is applied. FIG. 1 is a side view, and FIG. 2 is a front view. The machining center 1 is a column 3 erected on a bed 2
A spindle device 11 provided movably in each of X, Y, and Z axes perpendicular to the axis; an arm drive mechanism 201 provided at a predetermined position above the spindle device 11; And a tool magazine section 101 provided above to accommodate a plurality of tools.

[0010] The spindle device 11 has a tool 301 mounted from the front end thereof, and a fastening release mechanism for clamping the tool 301 described later is provided inside. Also, the spindle device 1
1 drives the tool 301 to rotate, and X, Y,
It can be positioned at an arbitrary position in each direction of the Z-axis by a feed mechanism (not shown) built in the machining center 1, and when the tool 301 is replaced, the tool 301 is moved and positioned at a tool replacement position Pc in the figure.

The tool magazine 101 has a plurality of tool pots 102 for holding tools arranged on the same circumference.
These tool pots 102 are provided on a disk 103 that rotates about a predetermined rotation axis. The disk 103 provided with the tool pot 102 is driven by a drive motor (not shown), and moves to a predetermined position in order to hold the tool pot 102 holding a desired tool 301 with the tool changing arm 203. Tool magazine part 10
For example, a moving mechanism (not shown) for moving the tool moved to a predetermined position to a standby position PH located on the outer circumference of the circumference on which the tool pots 102 are arranged is provided at 1.

The arm driving mechanism 201 has an arm holding shaft 202 for holding a tool changing arm 203, and a driving mechanism for rotating and linearly moving the arm holding shaft 202 in accordance with a predetermined tool changing operation. The details of the arm drive mechanism 201 will be described later. The tool exchanging arm 203 is provided at both ends with gripping portions 203a and 203b for gripping a tool, respectively.

FIG. 3 shows a spindle device 1 of the machining center 1.
1 is a cross-sectional view illustrating a configuration example of FIG. In FIG. 3, the spindle device 11 has a spindle main body 12, a motor unit 31, and a fastening release mechanism unit 51. The main spindle body 12 includes bearings 15, 1
It is rotatably held by a cylindrical case member 13 via 6 and 17 and a rear holding member 14 fixed to the rear end of the case member 13. In addition, the spindle body 12
Are a member 18 for retaining the bearing 15 fixed to the tip of the member 13, a member 20 for retaining the bearing 17 fixed to the rear end of the rear holding member 14, and a rear end of the main spindle body 12. The axial movement is restricted by the retaining member 19 of the screwed bearing 17. The main spindle body 12 has a tapered tool mounting hole 12a at its tip along the central axis.
Are formed in the tool mounting hole 12a.
Is fitted and mounted.

The motor section 31 has a rotor 32, a stator 33, and a stator holding member 35. The rotor 32 is fitted and fixed to the shaft portion of the main spindle body 12, and is made of, for example, a permanent magnet or a field winding. Stator 3
Reference numeral 3 denotes, for example, a three-layer armature winding 34 wound around an armature core, which is fitted and fixed to the inner periphery of a stator holding member 35 so as to have a predetermined gap with the rotor 32. I have. The stator holding member 35 is fitted and fixed to the inner periphery of the case member 13, and forms a flow passage 35 a through which oil or air passes between the stator holding member 35 and the inner peripheral surface of the case member 13. By supplying a cooling medium from a fluid supply unit (not shown) to the flow path 35a, the stator 33
It can be cooled.

The fastening release mechanism 51 mainly includes a tool 301
Mechanism for fastening the tool and the tool 3 by the fastening mechanism
And a release mechanism for applying a release force to release the fastening of the main body 01. The engagement mechanism includes an engagement claw provided in a through hole 12b formed along the center axis of the main spindle body 12. 53, a rod 55 movably provided in the through hole 12b, and a disc spring 56 inserted into the rod 55.

A through hole 12b formed in the main spindle body 12
Communicates with the tool mounting hole 12a and
The inner peripheral diameter of the boundary region with is enlarged. Engaging claw 53
Is a gripping portion 3 formed at the rear end of the tool 301 at the front end.
The hook 55 has a claw portion that can be engaged with the rod 01b, and the rear end portion is locked by an engagement portion 55a at the distal end of the rod 55 by a ring spring 54. A plurality of engaging claws 53 are locked around the engaging portion 55a at the tip of the rod 55, and the plurality of engaging claws 53 open and close at the same time as the rod 55 moves in the axial direction. That is, when the rod 55 moves rearward in the axial direction, the engaging claw 53 is pressed by the inner peripheral surface of the through hole 12 b formed in the main spindle body 12 and closed, and the tool inserted into the tool mounting hole 12 a of the main spindle body 12. It is engaged with the engaged portion 301b of 301. Further, when the rod 55 moves forward in the axial direction, the engaging claw 53 opens by moving along the enlarged portion of the through hole 12b formed in the main spindle body 12, and the engaged portion of the engaged tool 301 is engaged. Release 301b.

The rod 55 has an engaging claw 53 at its tip.
, The disc spring 56 is inserted into the shaft portion, and the stopper member 57 is fitted and fixed to the shaft end portion. In addition, rod 5
The rear end portion 5 projects outside through a through hole 19 a of a retaining member 19 screwed to the rear end portion of the main spindle body 12. The disc spring 56 is accommodated in the disc spring accommodating portion 12c formed in communication with the through hole 12b of the spindle main body 12 while being inserted into the rod 55, and is fitted and fixed to one end of the disc spring accommodating portion 12c. Both ends of the regulating member 58 and the stopper member 57 at the shaft end of the rod 55 are in contact with each other.
The stopper member 57 is fitted and inserted into the disc spring accommodating portion 12c, and is prevented from falling out of the disc spring accommodating portion 12c by the retaining member 19 screwed to the rear end portion of the main spindle body 12. . The disc spring 56 has a stopper member 57.
To the rear in the axial direction, whereby the rod 5
5 is urged rearward in the axial direction, and the locking claw 53 is normally in a closed state.

The release mechanism of the fastening release mechanism 51 has a lever member 63, a rod member 66, and a rotating member 69. The lever member 63 is rotatably held around a rotation shaft 64 by a base member 61 fixed to a holding member 61 fixed to the rear holding member 14. In the middle of the shaft portion of the lever member 63, a convex contact portion 63a that contacts the shaft end of the rod 55 is formed, and a spherical connecting portion 63b is formed at the distal end portion.

The rod member 66 is supported by a shaft support member 68 fixed on the base member 62 so as to be movable in a direction parallel to the axial direction of the main spindle body 12, and has a connecting portion 63b of the lever member 63 at one end. Is formed at the other end, and a locking portion 66b for locking the coil spring 67 is formed at the other end.
A connection hole 66c into which a is fitted is formed. A coil spring 67 is inserted into the rod member 66, and both ends of the coil spring 67 are locked to one end of the shaft support member 68 and a locking portion 66 b of the rod member 66, respectively. The coil spring 67 urges the rod member 66 rearward in the axial direction.

The rotating member 69 is rotatably held about a rotating shaft 70 held by a block member 73 fixed to the lower surface of a holding plate 72 fixed to an end of the rear holding member 14. A connecting portion 69 having a spherical tip in a direction substantially orthogonal to each other at a substantially equal radius position from the center of the rotating shaft 70.
a and the contact portion 69b are formed. Rotating member 69
The connection portion 69a of the rod member 66 is connected to the connection hole 66 of the rod member 66 described above.
c, and the contact portions 69b are indicated by arrows A1 and A2.
Abuts on an axial end of a linear motion rod 91 described later that is linearly moved in the direction. Also, the holding plate 72 near the rotating member 69
On the upper side, a bolt member 71 is provided to abut on a part of the rotating member 69 to restrict the rotation of the rotating member 69.

In the release mechanism of the fastening release mechanism 51 having the above structure, the rod member 66 is normally urged rearward in the axial direction by the urging force of the coil spring 67, and the rod member 6
The contact portion 63 a of the lever member 63 connected to 6 is not in contact with the shaft end of the rod 55. From this state, when the linear motion rod 91 descends in the direction of arrow A2, the rotating member 69 is rotated in the direction of arrow B2 while the shaft end of the linear motion rod 91 contacts the contact portion 69b of the rotating member 69. Let it. When the rotating member 69 rotates in the direction of arrow B2, the rod member 6 connected by the connecting portion 69a of the rotating member 69
6 is linearly moved in the direction of arrow C2 against the urging force of the coil spring 67. When the rod member 66 moves in the direction of arrow C2, the lever member 63 connected to the rod member 66 pivots in the direction of arrow D2, and the contact portion 63a of the lever member 63
Abuts against the shaft end of the rod 55 and presses the rod 55 forward in the axial direction. The rod 55 moves forward in the axial direction against the urging force of the disc spring 56, and the forward movement in the axial direction of the rod 55 causes the engaging claw 53 at the tip of the rod 55 to open.
The engaged portion 301b of the tool 301 that has been fastened is released.

FIG. 4 is a sectional view of the arm drive mechanism 201 as viewed from the axial direction of the spindle device 11. The arm drive mechanism 201 includes a drive motor 210 and the tool change arm 20.
And an arm drive cam mechanism 204 for driving the tool 3 in accordance with a predetermined tool change operation, and a release force required for releasing the tool 301 of the fastening release mechanism 51 from the rotational driving force of the drive motor 210. It mainly comprises a release force generating cam mechanism 151 that is generated in cooperation with the replacement operation.

In FIG. 4, the arm drive cam mechanism 20
Reference numeral 4 is mainly formed in a space surrounded by the frame FL2, and includes a transmission shaft 212 to which the rotational driving force of the driving motor 210 is transmitted, and a groove in which a cam for defining the linear motion of the tool changing arm 203 is formed. A cam member 220, a roller gear cam member 221 having a cam for defining a turning operation of the tool changing arm 203, and a cam holding shaft 216 holding the groove cam member 220 and the roller gear cam member 221.
A driven lever 231 driven by the groove cam member 220;
It has a driven roller member 272 that follows a cam formed on the roller gear cam member 221, and an arm holding shaft 202 that holds the tool changing arm 203.

The transmission shaft 212 has one end connected to the coupling 21.
2, the shaft portion is rotatably held by a holding member 214 fixed to the frame FL1 via bearings BR1 and BR2, and the other end is connected to the bearing BR3. It is rotatably held by the frame FL2 via the frame FL2. Transmission shaft 2
A gear 215 is fitted and fixed to the shaft portion 12.

One end of the cam holding shaft 216 has a frame FL.
1 is rotatably held via a bearing BR7 by a holding member 216a fixed on the shaft FL.
It is held rotatably via R5 and the other end is a frame FL
2 is rotatably held via a bearing BR4. A groove cam member 220 and a roller gear cam member 221 are fitted and fixed to the cam holding shaft 216, and a driven lever 231 is rotatably held via a bearing BR6.

The groove cam member 220 has a gear 220b meshed with the gear 215 on the outer periphery, and a cam groove 220a on a side surface of which a driven roller 231a provided at a lower end of the driven lever 231 is fitted. Is formed. The cam groove 220a has a cam curve that defines the linear motion of the tool changing arm 203.

The driven lever 231 has a driven roller 231a fitted in the cam groove 220a of the grooved cam member 220, and has a roller 2 at the tip bent downward.
32 are rotatably held.

The roller gear cam member 221 is formed on its outer periphery with a groove cam meshing with a plurality of rollers 273 held on the outer periphery of a driven roller member 272, and this groove cam defines a turning operation of the tool changing arm 203. It has become.

The driven roller member 272 is connected to the cam holding shaft 21.
Rotation shaft 271 held rotatably in a direction orthogonal to 6
, And the rotation of the roller gear cam member 221 causes the rotation shaft 271 to rotate. A gear 274 is fixed to the rotating shaft 271 together with the driven roller member 272, and the gear 274 is rotated by the rotating shaft 271.

The arm holding shaft 202 is rotatably held by the frame FL2 and is held movably in the axial direction. The arm holding shaft 202 holds the center of the tool change arm 203 at the tip, and also holds a gear 275 that meshes with the gear 274 described above. The arm holding shaft 202 is axially engaged with a roller 232 provided at the tip of the driven lever 231 described above, and the driven lever 231 is
When the roller 23 turns following the cam groove 1220a of
The arm holding shaft 202 is directly moved by the axial engagement between the arm holding shaft 202 and the arm holding shaft 202.

The release force generating cam mechanism 151 includes a plate cam member 152 having a cam formed on the outer periphery formed by the rotation driving force of the drive motor 210 in cooperation with the tool changing operation of the tool changing arm 203, and a plate cam member. A driven rod 159 that is driven by a cam formed at 152;
And a connection shaft 162.

The plate cam member 152 is formed by the groove cam member 2 described above.
20 and a cam holding shaft 216 for holding the roller gear cam member 221. The driven rod 159 is connected to the cover member 1 fixed on the frame FL1.
58 and the supporting member 160 are movably held in the axial direction. One end of the driven rod 159 has a shaft 15
3 is fixed, and the holding member 155 is fixed.
5, a driven roller 154 that is in contact with the cam surface 152a of the plate cam member 152 is rotatably held. Also,
At the other end of the driven rod 159, a connection recess 159a is formed.

The connecting shaft 162 is provided in a direction perpendicular to the driven rod 159 (a direction parallel to the axial direction of the spindle device 11), and is rotatably held by a holding member 161 fixed to the frame FL3. The rotating lever 163 is fixed and held on the connecting shaft 162, and has a spherical connecting portion 163a that fits into the connecting concave portion 159a of the driven rod 159 at the distal end.

FIG. 5 is a top view of the release force generating cam mechanism section 151. When the cam holding shaft 216 holding the groove cam member 220 and the roller gear cam member 221 rotates, the driven roller 154 causes the plate cam member 152 to rotate. Is driven by the cam surface 152a on the outer periphery, and the driven rod 159 moves linearly in the directions of arrows E1 and E2. Arrow E1 of the driven rod 159
And the movement in the E2 direction, the rotation lever 163
The connection shaft 162 is rotated in the directions of the arrows F1 and F2.

FIG. 6 is a sectional view showing the structure of a transmission mechanism for transmitting the release force generated from the release force generating cam mechanism 151 from the connecting shaft 162 to the linear motion rod 91. A rotation lever 94 longer than the above-described rotation lever 163 is further fixed to a connection shaft 162 rotatably held by a holding member 161 fixed to the frame FL3, and a spherical connection portion 163a is provided at a tip end. Are formed. The linear motion rod 91 has a through hole 9 formed in a holding member 92 fixed to the frame FL4 and the frame FL5.
2a, and at the upper end of the linear motion rod 91,
A connecting recess 91b into which the connecting portion of the rotating lever 94 is fitted is formed. Stepped portion 9 of through hole 92a of holding member 92
One end of a coil spring 93 in a state where the linear motion rod 91 is inserted is locked and held in 2b, and the other end of the coil spring 93 is in contact with a stepped portion 91c of the linear motion rod 91. The coil spring 93 includes a linear motion rod 91
In the direction of pushing up the holding member 92 in the direction of arrow A1. In the transmission mechanism having the above-described configuration, the rotation lever 94 is turned by the arrow G1 with the rotation of the connection shaft 162.
And the direction of G2, and the rotation of the rotation lever 94 causes the linear motion rod 91 to linearly move in the directions of arrows A1 and A2.

Next, an operation example of the automatic tool changer according to the present embodiment will be described with reference to a cam diagram shown in FIG. FIG. 7A shows the plate cam member 152 (the cam holding shaft 21).
FIG. 7B is a diagram illustrating the clamping operation and the unclamping operation (movement amount of the driven rod 159) of the fastening release mechanism unit 51 according to the rotation angle of 6), and FIG. 7B illustrates the roller gear cam member 221 (cam holding shaft 216). FIG. 7C is a diagram illustrating the turning angle of the tool changing arm 203 according to the rotation angle, and FIG. 7C illustrates the stroke amount (movement amount) of the tool changing arm 203 according to the rotation angle of the grooved cam member 220 (cam holding shaft 216). FIG.

In the tool changing operation, the tool 301 accommodated in the tool magazine 101 is moved to the standby position PH, the spindle device 11 is moved to the tool changing position Pc, and the tool 301 accommodated in the tool magazine 101 is Each of the tools 301 mounted on the spindle device 101 is moved to a position where it can be gripped by the grippers 203a and 203b of the tool change arm 203. At this time, the tool change arm 203
Is positioned at a predetermined reference position, for example, a position inclined by 75 degrees with respect to a straight line connecting the standby position PH and the tool change position Pc.

Next, the drive motor 210 of the arm drive mechanism 201 is driven to rotate the cam holding shaft 216 in a predetermined direction. As shown in FIG. 7B, when the cam holding shaft 216 is rotated by 10 degrees, the tool change arm 2
03 starts turning. As shown in FIG. 7A, when the cam holding shaft 216 is rotated by 50 degrees, the plate cam member 152 starts the movement of the driven rod 159 by overlapping with the turning operation of the tool changing arm 203. Driven rod 15
9, the rotation lever 163 rotates in the direction of arrow F2, the rotation lever 94 rotates in the direction of arrow G2 via the connecting shaft 162, and the linear motion rod 91 descends in the direction of arrow A2. Then, the turning member 69 turns in the direction of arrow B2, and the rod member 66 moves directly in the direction of arrow C2, and the lever member 6
3 rotates in the direction of arrow D2. The rod 55 is pushed forward in the axial direction by the contact portion 63a of the lever member 63, and the unclamping operation of the tool 301 starts when the engaging claw 53 at the tip of the rod 55 starts to open.

As shown in FIG. 7B, the turning operation of the tool change arm 203 is stopped when the cam holding shaft 216 is rotated by 75 degrees, and the respective tools located at the standby position PH and the tool change position Pc are stopped. 301 is gripped by gripping portions 203a and 203b of the tool changing arm 203, respectively. As shown in FIG. 7C, the cam holding shaft 216
At the time of the rotation by 0 degree, the linear movement operation of the tool changing arm 203 (tool 3) overlaps with the unclamping operation of the tool 301.
01 sampling operation) is started.

As shown in FIG. 7A, the cam holding shaft 21
The unclamping operation of the tool 301 is completed when the 6 is rotated 95 degrees, the engaging claw 53 at the tip of the rod 55 is completely opened, and the tool 301 is completely released from the main spindle body 12. As shown in FIG. 7B, the cam holding shaft 21
6 is rotated 130 degrees, the tool change arm 203
Is started again, and the tool 301 mounted on the spindle main body 12 is turned while being extracted by the tool exchange arm 203.

As shown in FIG. 7C, the cam holding shaft 21
6 is rotated 150 degrees, the tool change arm 203
Is completed, and when the cam holding shaft 216 is rotated 220 degrees, the standby position P gripped by the tool changing arm 203 is completed.
The operation of inserting the new tool 301 in H into the main spindle body 12 is started. New tool 30 at standby position PH
1 is when the cam holding shaft 216 is rotated 240 degrees,
It moves on the axis of the main spindle body 12.

As shown in FIG. 7A, the cam holding shaft 21
6 is rotated 275 degrees, the tool change arm 203
The clamping operation of the tool 301 is started simultaneously with the operation of inserting the new tool 301 into the main spindle body 12 at the standby position PH. The clamp operation of the tool 301 is performed by moving the driven rod 159 in the direction of the arrow E1 so that the linear motion rod 91 is raised in the direction of the arrow A1 by the urging force of the coil spring 93, and the rod member 66 is pressed by the urging force of the coil spring 67. Moves directly in the direction of arrow C1,
This is performed when the lever member 63 rotates in the direction of the arrow D1 and the contact portion 63a of the lever member 63 does not press the shaft end of the rod 55.

As shown in FIG. 7C, the cam holding shaft 21
6 is rotated 280 degrees, the tool change arm 203
7B, the operation of inserting the tool 301 into the main spindle body 12 is completed, and as shown in FIG.
At the time when the tool change arm 203 is rotated by 5 degrees, the tool change arm 203 rotates by a predetermined angle in a direction opposite to the above. As shown in FIG. 7A, when the cam holding shaft 216 is rotated by 315 degrees, the clamping operation of the tool 301 to the main spindle 12 body is completed, and the tool 3 which is located at the standby position PH and the main spindle body 12 respectively.
01 exchange operation is completed.

As described above, according to this embodiment, the tool 3 clamped by the fastening release mechanism 51 of the spindle body 12
01 is generated by providing a plate cam member 152 on the cam holding shaft 216 of the cam mechanism 204 for causing the tool change arm 203 to perform a predetermined tool change operation. A tool for clamping a tool to the distal end via a transmission mechanism including a rod 159, a rotating lever 163, a connecting shaft 162, a rotating lever 94, a linear motion rod 91, a rotating member 69, a rod member 66, and a lever member 63. The transmission is performed to the rod 55 provided with the engagement claw 53. For this reason, for example, the fastening and releasing operations can be performed in accordance with the cam diagram shown in FIG. 7, and the time for the tool changing arm 203 to wait for insertion and removal of the tool 301 can be omitted. Thus, the time required for tool change can be reduced. Further, according to the present embodiment, the roller gear cam member 221 for defining the turning operation and the linear movement operation of the tool changing arm 203, and the plate cam member 152 for defining the fastening and releasing operation of the groove cam member 220 and the tool 301 are formed by the cam holding shaft. 216, the fastening release operation of the tool 301 and the tool changing arm 203
The coordination with the turning operation and the linear motion of the tool is reliable, and the tool can be reliably changed. Further, according to the present embodiment, the turning operation and the linear movement operation of the tool changing arm 203 and the fastening and releasing operation of the tool 301 can be overlapped at the maximum, and the time required for tool changing can be greatly reduced. it can. Further, according to the present embodiment, the size and the positional relationship of each component of the release force transmitting device provided between the plate cam member 152 and the rod 55 are adjusted, so that the tool 301 is unclamped. The release force can be arbitrarily adjusted, and the stroke amount for moving the rod 55 can be arbitrarily adjusted.

[0045]

According to the present invention, the tool change time can be shortened, and the tool changing operation can be reliably performed.

[Brief description of the drawings]

FIG. 1 is a side view showing an example of a configuration of a machining center to which the present invention is applied.

FIG. 2 is a front view of the machining center of FIG.

FIG. 3 is a sectional view showing a configuration example of a spindle device of a machining center to which the present invention is applied.

FIG. 4 is a cross-sectional view of the arm drive mechanism as viewed from the axial direction of the spindle device.

FIG. 5 is a view of the release force generating cam mechanism as viewed from above.

FIG. 6 is a cross-sectional view showing a configuration of a transmission mechanism for transmitting a releasing force generated from a releasing force generating cam mechanism from a connecting shaft to a linear motion rod.

FIG. 7 is a diagram illustrating a clamping operation and an unclamping operation of a fastening release mechanism, a turning angle of a tool changing arm, and a stroke amount according to a rotation angle of a cam holding shaft.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 11 ... Spindle device 12 ... Spindle main body 51 ... Fastening / releasing mechanism part 151 ... Release force generation cam mechanism part 152 ... Plate cam member 101 ... Tool magazine part 201 ... Arm drive mechanism part 203 ... Tool exchange arm 216 ... Cam holding shaft 220 ... Groove cam member 221: roller gear cam member

Claims (2)

[Claims] 1. A tool change arm having gripping portions for gripping a tool at both ends, holding the tool change arm, and turning the tool change arm around a predetermined rotation axis and in the direction of the rotation axis. An arm drive mechanism for performing a predetermined tool change operation including a linear motion; a drive motor provided in the arm drive mechanism for driving the arm drive mechanism; and a predetermined tool for the tool change arm The tool is built in a main shaft movably provided at a gripping position, engages with the tool by a fastening force by an elastic force of elastic means, fastens the tool to the main shaft, and releases the tool by a release force against the fastening force. A fastening release mechanism for releasing engagement with a tool, and a release force for the fastening release mechanism in association with a predetermined tool changing operation of the tool changing arm is generated from a rotational force of the drive motor. An automatic tool changer comprising: a cam mechanism that causes the cam mechanism to release a release force supplied from the cam mechanism; and a release force transmission mechanism that transmits a release force to the fastening release mechanism via a predetermined transmission path. 2. The automatic tool changer according to claim 1, wherein the arm drive mechanism has a cam mechanism that defines a predetermined tool change operation including a turning operation and a linear operation of the tool change arm.