JPH0158012B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an automatic tool changer for a transfer machine.

Generally, a transfer machine is used in which a large number of processing units are installed side by side along a conveyance line, and these processing units sequentially process workpieces mounted on a pallet.
In such transfer machines, for example, when the workpiece is changed or when the tool attached to the main shaft of the machining unit becomes worn out and becomes unusable, it is necessary to replace the tool for each machining unit. be.

Conventionally, tool exchange on a transfer machine as described above involves running a pallet carrying the tools to be exchanged along a conveyance line, positioning the pallet in front of the processing unit where the tool needs to be exchanged, and stopping the pallet. After the tool was removed, the worker replaced the tool manually. However, such manual tool replacement by workers takes a long time, and
Since the transfer machine had to be stopped during this time, there was a problem in that its operating rate decreased.

Furthermore, as shown in Fig. 3 of Japanese Patent Application Laid-open No. 54-64780, a pallet for mounting replenishment tools is arranged on the table TAB of the MC, and a plurality of tools are arranged radially above and below this pallet for mounting replenishment tools. , the pallet with the replenishment tool is moved horizontally to the spindle SPD.
An automatic tool changer is also known in which a tool on a replenishment tool mounting pallet is mounted on the spindle by moving the tool in the direction. However, this automatic tool changer has a problem in that it takes a long time to change tools because the tools are transferred one by one between the MC spindle SPD and the replenishment tool mounting pallet.

This invention solves the problems of the conventional ones described above, and allows tools to be replaced in a short time.
It is an object of the present invention to provide an automatic tool changing device for a transfer machine that can shorten the stop time of the transfer machine and thereby improve the processing efficiency of a workpiece.

In order to achieve this object, an automatic tool changer for a transfer machine according to the present invention includes a tool support pallet that runs along a conveyance line, with a support body erected in parallel with the conveyance line, and a support body erected in parallel with the conveyance line. , a pair of tool sockets that removably hold the tool to be replaced in the same direction as the tool mounted on the main shaft of the processing unit are arranged in the transport direction of the transport line,
and a tool to be replaced with a tool mounted on the spindle at a tool exchange position on the upper part of the processing unit, the tool sockets being mounted at a distance from each other, and forming a notch located between the pair of tool sockets in the support body. a tool holder that holds the tool, an exchange arm with an axis parallel to the main spindle centered between the tool holder and the tool exchange position of the main spindle, and an exchange arm that holds the tool of the main spindle or the tool socket. arm operating means for moving the tool forward and backward in the direction of attachment and detachment, and for rotating the exchange arm around the axis; gripping parts for releasably gripping the tool are provided at both ends of the exchange arm; and the tool is replaced with these gripping parts. The distance between the arm axis, the distance between this axis and the tool exchange position of the main spindle, and the distance between the axis and the tool holder are made to match, and the distance between the gripping parts of the exchange arm and the attachment to the support body are made to match, respectively. The tool socket is provided with a machining unit feeding device for advancing and retracting the machining unit together with the tool holder so that the exchange arm passes through the notch in the support.

Hereinafter, one embodiment of the present invention will be described with reference to the drawings.

FIG. 1 shows an outline of the transfer machine. In FIG. 1, reference numeral 1 denotes a conveyance line, and along this conveyance line 1 there is provided a processing station 3 in which a large number of processing units 2 are installed side by side, and at one end of this processing station 3 there is a standby station 4. At the other end, a loading station 6 and an unloading station 6 are provided via a buffer station 5, respectively. Further, a pallet return conveyor 7, a jig setup change conveyor 8, and a tool setup change conveyor 9 are provided parallel to the conveyance line 1, and both ends of these conveyors 10 and 11 are connected. Transport line 1
is connected to. In FIG. 1, 12 and 13 are pallets for placing workpieces, and 14 and 15 are pallets for supporting tools.

During normal machining, the transfer machine shown in FIG. Part of the connecting conveyor 11, pallet return conveyor 7, connecting conveyor 10
and waiting station 4, arrow a
As shown in the figure, the workpiece is conveyed to the conveyance line 1, positioned and stopped in front of each machining unit 2 of the machining station 3, and machining of the workpiece is performed.After machining is completed, the workpiece is conveyed to the loading/unloading station 6. . After the workpiece that has been processed at the station 6 is taken out from the workpiece mounting pallet 12, an unprocessed workpiece is mounted and the above-described operations are repeated.

In addition, when changing the workpiece, first, one of the workpiece mounting pallets 12 from which the processed workpiece has been removed at the loading/unloading station 6 is placed on the path indicated by the arrow C1 for jig setup. At the same time as returning it to the conveyor 8, the empty tool support pallet 14 is conveyed from the tool changeover conveyor 9 to the conveyance line 1 along the route shown by the arrow b2, and stopped in front of the required machining unit 2, as will be described later. After the tool is removed, it is returned to the tool changeover conveyor 9 along the path indicated by the arrow b1. Next, the tool support pallet 15 supporting the new tool was conveyed from the tool changeover conveyor 9 to the conveyance line 1 along the path indicated by arrow b2, and the tool was mounted in front of the machining unit 2 as described later. Then, return it to the tool setup conveyor 9 again. Thereafter, the other workpiece mounting pallet 13 is conveyed from this conveyor 8 to the loading/unloading station 6 via the conveyance line 1 along the path indicated by the arrow c2.
Here, the other workpiece is mounted on the other workpiece mounting pallet 13, and the workpiece is processed in almost the same manner as in the case of the one workpiece mounting pallet 12 described above, except that the tools are replaced. I do.

Incidentally, in case of wear or damage of the tools, only the tool supporting pallets 14 and 15 need to be transported to the transport line 1.

The present invention is applied to the transfer machine having the above configuration, and an automatic tool changer according to one embodiment thereof is configured as follows. As shown in FIG. 2, a feed table 18 is supported on the bed 16 via a support table 16a so as to be movable forward and backward by a servo motor (processing unit feed device) 17. Unit 2 is fixed. Processing unit 2 has the
As shown in the figure, a horizontal main shaft 20 is provided which is rotated around the axis by a main shaft drive motor 19, and a main shaft head 21 is fixed to the tip of this main shaft 20. A feed screw 22 perpendicular to the axial direction is rotatably supported, and a bevel gear 23 fitted and fixed to the feed screw 22 is connected to a bevel gear 25 provided on a shaft 24 concentric with the main shaft 20, which is fitted and supported. They are meshed, and the shaft 24 is rotated about the shaft by a tool feed motor 26. A tool holder 28 is fixed to a feed nut 27 which is threadedly fitted to the feed screw 22, and the tool holder 28 is supported by the spindle head 21 so as to be able to reciprocate in the radial direction. The tool holding stand 28 is provided with a normal tool clamping mechanism 32 composed of a disc spring 29, a ball 30, a gripping member 31 for holding the ball 30, etc., and a tool 33 with a pull stud is attached and detached by this clamping mechanism 32. Possibly held. A push rod 34 whose tip faces the gripping member 31 is supported by the main shaft 20 so as to be movable forward and backward, and the push rod 34 is moved forward and backward by a forward and backward movement means (not shown). When the tool feed motor 26 is driven, the feed screw 22 rotates via the shaft 24 and bevel gears 25 and 23, and the rotation of the feed screw 22 causes the feed nut 27 to move in the radial direction of the main shaft 20. The tool 33 is moved in the radial direction of the main shaft 20 via the tool holder 28.
Note that the tool holding table 28 is reciprocated for facing processing between a position where the axial directions of the tool 33 and the main shaft 20 coincide and a position where these are eccentric by a predetermined eccentric amount. Further, the tool holding base 28 is arranged so that the tips of the gripping member 31 and the push rod 34 face each other, and the push rod 34 is advanced by the advancing/retreating means.
1 to the right in FIG. 3, the clamping of the tool 33 by the clamping mechanism 32 is released.

Further, as shown in FIG. 2, a fixing table 35 for the conveyance line 1 is arranged on the front side of the bed 16, and on this fixing table 35, the pallets 12, 1
A transfer bar 36 for conveying the parts 3, 14, and 15 is provided, and a cylinder mechanism 37 for actuating the clamper is arranged at a position facing the processing unit 2.
are fixed on both sides of the fixed base 35, and the cylinder mechanism 3
A clamper 38 that removably engages with the pallet is fixed to the piston rod 37b of No. 7, and in FIG.
9, the tool is positioned and fixed in front of the machining unit 2 where the tool is to be replaced. As shown in FIGS. 2 to 6, the tool support pallet 14 has a support 41 fixed on a pallet body 40, and tool sockets 42 fixed on the front and rear ends of the support 41, respectively. A notch 41a with an open upper surface is formed in the support body 41 between these. The tool socket 42 is adapted to removably hold a tool 33a to be replaced in the same direction as the tool 33 mounted on the main shaft 20 of the processing unit 2. That is, a pair of front and rear pressing pins 43 are supported at the end of the tool socket 42 on the processing unit 2 side so as to be slidable in the radial direction, and are biased toward the center side of the tool socket 42 by a spring 44, so that the pressing pins 43 are The opposite end of the bottle 43 is adapted to be pressed against the outer periphery of the pull stud portion of the tool 33. The support body 4
A lock lever 45 is pivotally attached to the machining unit 1 so as to be able to swing in the left-right direction as shown in FIG.
The outer end of the pressing bottle 43 is always supported by the fork portion 45a, and a pin escape groove 45b is formed in the fork portion 45a on the side of the processing unit 2 from these supporting portions, and one side of the fork portion 45a A contact bolt 47 is protruded toward the processing unit 2 so that its position can be adjusted. In addition, 46 in Figure 3
A is a support pin that regulates the angle of inclination of the lock lever 45.

Furthermore, as shown in FIGS. 2 to 5 and 7, a tool changing mechanism 48 is provided on the processing unit 2. As shown in FIGS. The tool exchange mechanism 48 has a pair of guide rods 5 attached to a guide 49 fixed to the processing unit 2.
0 is supported so as to be movable back and forth, the tip of the exchange mechanism body 51 is fixed to the tip of the guide rod 50, and abutting members 52 that abut the abutting bolts 47 of the lock lever 45 are fixed to both sides of this tip. ing. A piston rod 53b of an advancing/retracting cylinder mechanism 53 is fixed to the end of the exchange mechanism main body 51,
The cylinder 53a of the advancing/retracting cylinder mechanism 53 is fixed to the processing unit 2. A cylinder 54a of a cylinder mechanism 54 for advancing and retracting the exchange arm is formed in the tip of the exchange mechanism main body 51, and a piston rod 54b extends toward the front side of the processing unit 2 integrally with a piston 54c fitted in the cylinder 54a. An exchange arm 55 is fixed to the tip of the exchange arm 55. Tool gripping parts 55c each having a curved part 55a and an engagement roller 55b facing the curved part 55a are provided at both ends of the exchange arm 55. A support shaft 56 extends toward the rear side of the processing unit 2 integrally with the piston 54c of the cylinder mechanism 54 for advancing and retracting the exchange arm, and a gear 57 that is long in the axial direction is formed on the support shaft 56. The exchange mechanism main body 51 includes a cylinder mechanism 5 for arm rotation.
The outer cylinder 58a of No. 8 is fixed, the outer cylinder 58a is fixed, the piston 58c is fitted to the inner cylinder 58b fitted to the outer cylinder 58b, and the piston rod 58d is fitted to the piston 58c.
is fixed, and a rack bar 59 fixed to the piston rod 58d meshes with the gear 57.
Note that the inner cylinder 58b of the tool turning cylinder mechanism 58 configured as a double cylinder, the piston 5
8c, piston rod 58d and rack bar 5
9 is adapted to move forward and backward in a horizontal direction perpendicular to the axial direction of the gear 57. The exchange mechanism main body 51
A tool holder 60 is fixed on the top, and a second tool 33b is removably held in the tool holder 60 parallel to and in the same direction as the tool 33 held on the tool holder 28.

Note that the axis of the exchange arm 55, that is, the support shaft 56, which is parallel to the main spindle 20, is arranged in the center between the tool exchange position of the main spindle 20 and the tool holding position of the tool holder 60 provided above the exchange arm. The distance between the tool gripping parts 55c, 55c provided at both ends of the support shaft 55, and the support shaft 56, and the support shaft 56 and the main shaft 2.
0 to the tool holding position and the distance between the support shaft 56 and the tool holding position of the tool receiver 60, respectively, and the distance between the tool gripping parts 55a and 55c and the support body 41 of the tool supporting pallet 14. The distance between the tool sockets 42, 42 attached to the tool sockets 42 and 42 are made to match.

Next, the operation of the automatic tool changer configured as described above will be explained.

As shown in FIG. 3, the tool 3 gripped by the clamp mechanism 32 of the tool holder 28 of the processing unit 2
3 is worn out, by stopping the main spindle 20 at a fixed position, the tool 33 is placed directly above the center of the main spindle 20.
Tool holder 2 is located at the tool exchange position where the axis center of
Stop 8. By driving the tool feed motor 26, the feed nut 27 is moved to a position facing the push rod 34. In this state, the forward/backward cylinder mechanism 53 of the tool exchange mechanism 48 is operated,
The exchange mechanism main body 51 is advanced to the right by the stroke A shown in FIG. advance.
After that, the outside of the arm rotation cylinder mechanism 58,
The cylinder 58a is operated and the piston rod 58
By moving the rack bar 59 in and out through d, the exchange arm 55 is rotated at 90 degrees through the support shaft 56, the piston 54c of the cylinder mechanism 54 for advancing and retracting the exchange arm, and the piston rod 54b. Rotate the exchange arm 55 to make it vertical, and make the gripping portion 55c face the tools 33 and 33b, respectively. Push rod 3 that was retreating during or after this operation
4 to the right in FIG. 3 and presses the gripping member 31 to release the clamping of the tool 33 by the clamping mechanism 32. After that, the exchange arm 55 is moved to the third position by the operation of the exchange arm advancing/retracting cylinder mechanism 54.
The tools 33 and 33b gripped by the grip portion 55c of the exchange arm 55 are pulled out from the tool holder 28 and the receiver 60, respectively, by advancing the stroke B shown in the figure to the right in FIG. Furthermore, after that, the arm rotation cylinder mechanism 58 is operated to move the replacement arm 55.
After rotating the tool 33 by 180 degrees, the worn tool 33 is connected to the receiver 60.
and the second tool 33b is placed on the tool holding base 2.
8 and face each other. In the same manner as described above, by retracting the exchange arm 55 only to the left side A in FIG. Clamp mechanism 32
hold it. In this way, tools 33 and 33
After replacing with tool 3, replace the replacement arm 55 with tool 3.
3, 33b to a position where it does not interfere with the main body 5 and 33b.
1 is also moved back to its original position. Note that the above-mentioned tool change operation is performed with the machining unit 2 in the backward position, and when the workpiece mounting pallet is stopped in front of the machining unit 2, the workpieces mounted on this pallet are Tools 33, 33b can be replaced without interference.

In addition, when the tools 33 and 33b mounted on the tool holder 28 and the receiver 60 are both worn out, or when the tools 33 and 33b are replaced due to a change in the workpiece, the machining unit 2 moves backward. In this state, one of the tool supporting pallets 14 that does not hold a tool in the tool socket 42 is placed on the front side of this.
The tool is transferred from the tool setup conveyor 9 to the conveyance line 1, and is positioned and fixed by the clamper 38 and knock pin 39 by the operation of the cylinder mechanism 37 in front of the machining unit 2 where the tool is to be replaced. Next, in the same manner as in the case of exchanging the tool 33 and the tool 33b described above, the tool holding table 28 is stopped at the tool exchange position,
The advancing/retracting cylinder mechanism 53 of the tool changing mechanism 48 is operated to move the changing mechanism main body 51 forward by the stroke shown in FIG. The grip part 5 is perpendicular to the
5c to grip the tools 33 and 33b, respectively.
Thereafter, the cylinder mechanism 54 for advancing and retracting the exchange arm is operated to advance the exchange arm 55 to the right in FIG. In this state, the processing unit feed servo motor 17 is driven to move the processing unit 2 forward via the feed table 18.
The exchange arm 55 is passed through the notch 14a provided in the support body 41 of the tool support pallet 14, and is advanced to the right by a stroke C shown in FIG.
1 to the side opposite to the machining unit 2 side, and the tool holder 28 and receiver 60 are moved forward until they are located on substantially the same vertical plane as the tool socket 42 provided on the support body 41. Furthermore, after that
The arm turning cylinder mechanism 58 is operated to change the exchange arm 55 from a vertical state to a horizontal state, and the tools 33, 33b held by the gripping portion 55c are opposed to the tool sockets 42 of the tool support pallet 14, respectively. Note that, as the processing unit 2 moves forward, the contact member 52 provided on the exchange mechanism main body 51
Since the lock lever 45 contacts and presses the abutment bolt 47, the lock lever 45 rotates against the lock spring 46, and the pin relief groove 45b is in a state opposite to the press pin 43. Tool 3 is attached to the grip part 55c.
Exchange arm 5 in a horizontal state holding parts 3 and 33b
5 is moved backward by B, and the tools 33, 33b are inserted into the tool sockets 42. In this case, the tool 33,
The pull stud part 33b pushes the pressure bottle 43 against the spring 4.
The tool 33, 33b is held in the tool socket 42, and the tool 33, 33b is held in the tool socket 42.
The gripping portion 55c of the exchange arm 55 is attached to the tools 33, 33.
Release the grip on b. Next, the exchange arm 55 is rotated vertically from the horizontal position, and the processing unit 2 is
At the same time, the replacement arm 55 and the like are moved back to a position where they do not interfere with the tool support pallet, and the pressure on the abutting bolt 47 by the abutting member 52 is released to separate them, and the locking lever 45 is moved by the restoring force of the locking spring 46. to return the rotation, and lock lever 45
The fork part 45a supports the press bottle 43, and the tool 3 held in the tool socket 42 is supported by the fork part 45a.
Lock 3, 33b. In this state, the clamper actuating cylinder mechanism 37 is reversely operated to release the clamper 38 and the knock pin 39 from fixing and engaging the tool supporting pallet 14.
The other tool supporting pallet 15, which is similar to the tool supporting pallet 14 except that the tool to be replaced is held and locked in the tool socket 42, is processed. Position and fix on the front side of unit 2. Thereafter, the processing unit 2 with the vertical exchange arm 55 is moved forward, and the exchange arm 55 is positioned on the opposite side of the support body 41 from the processing unit 2 side. Rotate the exchange arm 55 to make it horizontal, and attach the tool socket 42 to the grip part 55c.
The tool to be replaced is held in the tool socket 42, and the replacement arm 55 is moved forward again at B to remove the tool from the tool socket 42. Furthermore, after that, the exchange arm 55 is changed from a horizontal state to a vertical state, and its grip part 5
The tool held by 5c is transferred to the tool holding table 28 and the receiver 6.
0, respectively, and in this state replace the exchange arm 5.
5 is moved backward by B, the tool to be replaced is held on the tool holder 28 and receiver 60, and only the machining unit 2 is moved back by C. Next, with the exchange arm 55 horizontal, replace the exchange mechanism main body 51.
The tool is returned to its original position by A, and the tool support pallet 15 is released from its fixation and transported to the loading/unloading station.

Note that in this embodiment, worn tools 33, 33b
As described above, the tools 33 and 33b mounted on the tool holder 28 and the receiver 60 are both the same tool, but the invention is not limited to this. The tools 33 and 33a are different, and these are exchanged so that one machining unit 2 can perform two different machining operations on the same workpiece, or machining different workpieces. Good too.

Although the above explanation has been given for one machining unit 2, tools may be replaced in the same manner for any machining unit 2 on the conveyance line 1. Furthermore, the above-mentioned tool exchange operations are performed automatically in sequence based on signals from well-known electrical means.

As explained above, in the automatic tool changer for a transfer machine according to the present invention, a pair of tool sockets are installed side by side in the conveyance direction of a conveyance line on a support provided upright on a tool support pallet, and the tool sockets are attached to the support. A notch located between a pair of tool sockets is formed, and the notch is provided in the machining unit on an exchange arm having a tool gripping portion at both ends, and a tool holder is provided on the upper part of the machining unit. This allows two tools to be installed simultaneously from a pair of tool sockets to the tool holder and spindle provided in the machining unit, and also allows two tools to be attached to a pair of tool sockets from the tool holder and spindle. By being able to install them at the same time, it is possible to shorten tool replacement time. In addition, the tool holder can hold tools similar to or different from the tool mounted on the spindle, and the former can shorten the downtime of the transfer machine when the tool wears out or breaks. In the latter case, the switching time between the two types of machining can be shortened, and therefore, the workpiece can be machined efficiently by the transfer machine by improving its operating rate.

[Brief explanation of drawings]

FIG. 1 is a schematic plan view showing an example of a transfer machine equipped with an automatic tool changer according to the present invention, FIG. 2 is a schematic side view showing an embodiment of the present invention, and FIG. 3 is a top view of the main spindle and a pallet. FIG. 4 is a front view taken in the direction of the arrow in FIG. 3, FIG. 5 is a partial plan view taken in the direction of the arrow in FIG. 3, and FIG. 6 is an enlarged cross-section taken along the - line in FIG. 3. 7 are enlarged sectional views taken along the - line in FIG. 2. 2... Machining unit, 14, 15... Pallet for tool support, 17... Servo motor for feeding the processing unit, 18... Feeding stand, 20... Main shaft, 21...
...Spindle head, 28...Tool holding stand, 33, 33
a, 33b...Tool, 42...Tool socket, 4
8... Tool exchange mechanism, 51... Exchange mechanism main body, 5
3... Cylinder mechanism for advancing and retreating, 54... Cylinder mechanism for advancing and retreating exchange arm, 55... Exchange arm, 55
c...Tool gripping part, 57...Gear, 58...Arm rotation cylinder mechanism, 59...Rack bar, 6
0...Tool receiver.

Claims (1)

[Claims] 1 In a transfer machine that sequentially processes workpieces mounted on pallets using multiple processing units arranged along a conveyance line, a support is placed parallel to the conveyance line on a tool support pallet that runs along the conveyance line. A pair of tool sockets are installed vertically on the support body and are spaced apart from each other in the transport direction of the transport line, for removably holding the tool to be replaced in the same direction as the tool mounted on the main shaft of the processing unit. a notch located between a pair of tool sockets in the support body, and a tool holder mounted on the spindle at the top of the processing unit to hold a tool to be exchanged with the tool at the tool exchange position. an exchange arm with an axis parallel to the spindle centered between the tool holder and the tool exchange position of the spindle; and a direction in which the tool is attached to and removed from the spindle or the tool socket. an arm operation means for moving the exchange arm forward and backward and rotating the exchange arm about the axis; gripping parts for releasably gripping the tool are provided at both ends of the exchange arm; and these gripping parts and the axis of the exchange arm the distance between the shaft and the tool exchange position of the main spindle, and the distance between the shaft and the tool holder, respectively, and the distance between the grips of the exchange arm and the tool socket attached to the support body. and a processing unit feeding device for advancing and retracting the processing unit together with the tool receiver so that the exchange arm passes through the notch in the support. Tool changer.