JPH0346251B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application This invention relates to an optimal pallet exchange device for use in machine tools and the like.

Conventional technology FMS (flexible manifold operating system) includes a machine tool body and a pallet exchange device. The pallet exchange device is used to exchange a pallet set on the table of a machine tool with another pallet. Conventional pallet exchange devices include hydraulic cylinder type and chain drive type.

For example, in a hydraulic cylinder type machine, one pallet can be set on the table of a machine tool by extending the rod of the hydraulic cylinder. After processing the work on the pallet,
The rod is retracted and the pallet is removed from the table.

In addition, in the case of a chain drive type, a plurality of pallets are attached to the chain at predetermined intervals. By driving the chain with a motor, any pallet is positioned on the table of the machine tool.

Problems to be Solved by the Invention However, the pallets and workpieces are quite heavy. Therefore, a hydraulic cylinder type pallet exchange device requires a large hydraulic cylinder. Furthermore, a chain-driven pallet exchange device requires a large drive motor and a thick chain.
Therefore, in either case, the device is large-scale and has a complicated structure.

In addition, it is difficult to remove shock from large hydraulic cylinders and large drive motors when starting and stopping. This is because, as mentioned above, the pallet and its workpieces are heavy, so the inertial force when moving them is large. Therefore, the shocks cannot be removed unless the large hydraulic cylinder and large drive motor are operated slowly. Therefore, the speed of pallet exchange cannot be increased.

OBJECTS OF THE INVENTION It is an object of the present invention to provide a pallet exchange device that is small and simple in structure without requiring special large hydraulic cylinders or large motors, and can significantly reduce costs.

SUMMARY OF THE INVENTION The present invention includes a support part 1, a table 2 that is set on the support part 1 and moves in at least one axis (for example, the X axis), and a table 2 that is detachable from the table 2 and movable on the table 2. The pallet 4 for transporting the workpiece to be set,
another pallet 14 for transporting workpieces located at a different location from the table 2; a driving means 3 equipped with something like a servo motor for moving the table 2 along one axis (for example, the X-axis); and the table 2. When the drive means 3 moves in one direction or the other direction of one axis (for example, the X axis),
A moving mechanism 12 is provided to move the workpiece conveyance pallet 4 onto the table 2 in one direction or the other direction by the driving force of the drive means 3. No driving means such as a hydraulic cylinder or a motor other than means 3 is required, and the moving mechanism engages with the rack fixed to the supporting part side while moving in one direction or the other direction along the table. The gist of the present invention is a pallet changing device characterized by a structure in which the rack and pinion are disengaged when a pallet for transporting a workpiece is clamped to the table, and the rack and pinion are engaged when the pallet is unclamped. .

Means for solving the problem Please refer to Figure 1. The pallet exchange device PC is
A pallet 4 for transporting workpieces that is removably attached to the table 2 and movable on the table 2.
and a location other than this table (in the example, the second
It has another pallet 14 for transporting workpieces located on the pallet stand 30) shown in the figure. and pallet exchange equipment
Support part 1 of PC (support part of machine tool in the example)
Table 2 is set above. This table 2 moves in at least one axis direction (in the embodiment, the X-axis direction). This table 2 is
It is possible to reciprocate along the one axis direction by means of a driving means 3 including a servo motor or the like.
A pallet 4 for transporting workpieces is configured to be removable from the table 2 and movable on the table 2. A moving mechanism 12 such as a pinion that moves together with a rack and a table fixed to the supporting part side moves the workpiece conveying pallet 4 on the table 2 in one direction X1 of the one axis direction.
Or move it in the other direction X2.
This movement of the pallet 4 is carried out by the driving force of the driving means 3 when the table 2 moves in one direction X1 or the other X2 of the uniaxial direction. The rack and pinion are disengaged when the pallet is clamped to the table, and the rack and pinion are engaged when the pallet is unclamped.

The pallet 4 is transferred using only the drive means 3, and no drive means other than the drive means 3, such as a hydraulic cylinder or a motor, is required.

Action See Figure 10. Table 2 is in the other direction
When moving in the direction X2, the workpiece conveying pallet 4 is similarly moved in the other direction X2 relative to the table 2 by the moving mechanism 12. Thereby, the workpiece conveyance pallet 4 can be moved from the table 2 to another location. (See Figure 9) At this time, the pallet is unclamped and the rack and pinion are engaged.

See FIG. 9. Table 2 is in one direction
When moving in the direction X1, the workpiece conveying pallet 4 moves in one direction X1 relative to the table 2. As a result, pallet 4 is set on table 2. (See Figure 10) The pallet is then clamped to the table. At this time, the rack and pinion become disengaged.

Example Please refer to FIG.

The pallet changing device PC of the present invention includes a machine tool support section 1, a table 2, a driving means 3, a pallet 4 for transporting workpieces, and a moving mechanism 12.

The support part 1 is set on the floor. The table 2 is set on the support part 1. A workpiece conveying pallet (hereinafter referred to as pallet) 4 has a workpiece 5 fixed thereto. This pallet 4 is set to be removable from the table 2 and movable in the X-axis direction.

The driving means 3 moves the table 2 in an X direction relative to the support part 1.
Axial direction, i.e. one direction X1 and the other direction X2
It is possible to move to Further, the moving mechanism 12 moves the pallet 4 in one direction on the table 2 when the table 2 moves in one direction X1 or the other direction X2.
It is designed to move X1 or the other direction X2.

See Figure 2.

FIG. 2 shows a vertical machining center 6 equipped with a pallet changing device PC of the present invention.
The support part 1 has a bed 7 and a saddle 8. The bed 7 is equipped with a servo motor 9 (for the Y axis).

The drive means 3 has a servo motor 10 (for the X axis) and a ball screw section 11. A table 2 is set above the saddle 8. A pallet 4 is set on the table 2 so as to be detachable and movable in the X-axis direction. The moving mechanism 12 is
It is provided near table 2.

The column 20 of the machining center 6 has a spindle head 21. A tool 23 is attached to the spindle 22 of this spindle head 21. The motor 24 is for rotating the spindle 22. spindle head 21
has an automatic tool changer 25. Further, the column 20 is provided with a panel 26, a CNC device 27, and a control panel 28.

The table 2 can be moved in one direction X1 or the other direction X2 by a servo motor 10. Palette stand 3 is next to table 2.
0 is set. Another pallet 14 is placed on this pallet stand 30.

See Figure 3.

A feed screw 34 of a ball screw portion 33 is attached to the servo motor 9. The feed screw 34 is engaged with a nut 35. A nut 35 is attached to the lower part of the saddle 8. Therefore, by operating the servo motor 9, the saddle 8 is moved to Y
It is movable in the axial direction. Also, servo motor 3
1, the spindle head 21 can be moved up and down in the Z-axis direction. FIG. 3 also shows a part of the moving mechanism 12, which will be described later.

Please refer to FIGS. 4 and 5.

The pallet stand 30 holds the pallets 4 and 14.
can be set side by side. palette 4 and 1
A workpiece 5 is fixed to each of the holes 4 and 4. The pallet table 30 has two air cylinders 40 and 41 built therein. Air cylinders 40 and 41 have stopper pins 42 and 43, respectively. Stopper pins 42 and 43 are connected to holes 4 in pallets 4 and 14, respectively.
It is designed to fit into a 4.45. This prevents the pallets 4 and 14 from being misaligned. When moving the pallets 4 and 14, the stopper pins 42 and 43 close the holes 4 by contracting.
Exit from 4,45. A rack 63 is fixed to the lower part of the pallet 4 along the longitudinal direction. A rack 91 is also fixed to the lower part of the pallet 14 along the longitudinal direction.

Both ends of the rack 63 protrude from the left and right ends of the pallet 4, respectively. Also, both ends of the rack 91 protrude from the left and right ends of the pallet 14, respectively.

In Figures 6 and 7, saddle 8, table 2,
A pallet 4, also called a pallet table, and a moving mechanism 12 are shown. In FIG. 6, a pallet 4 is clamped to the table 2. In FIG. 7, pallet 4 is unclamped.

The table 2 has a slide portion 50, two clamp cylinders 51, and a clamp plate 53. Clamp cylinders 51, 51 are fixed on the slide portion 50. One clamp cylinder 51 is located on the rear side of the other clamp cylinder 51, so it is not shown in FIGS. 6 and 7. Rod 52 of clamp cylinder 51
A clamp plate 53 is fixed to. Further, a nut 54 is fixed to the lower surface of the slide portion 50. This nut 54 has a ball screw portion 11.
The feed screws 55 are engaged with each other. This feed screw 55 is connected to the servo motor 10.

The pallet table 4 has parts 56, 56 and a cover 57. This cover 57 is provided to prevent chips and cutting oil from coming into contact with the rack 62, pinion 64, etc. These portions 56, 56 are adapted to come into contact with the lower surface of the clamp plate 53.

The moving mechanism 12 has a gear housing 61, racks 62, 63, and a support 67 for the rack 62. The lower end of this support body 67 is fixed to the front surface of the saddle 8. The gear housing 61 is the shaft 6
It has 8,69. A pinion 64 is fixed to one end of the shaft 68. A gear 66 is fixed to the other end of the shaft 68. A pinion 65 is fixed to the shaft 69. The gear housing 6
1 is fixed to a clamp plate 53.

As shown in FIGS. 6 and 7, the gear 66 is always in mesh with the pinion 65. In FIG. 6, when the pallet 4 is clamped, the rack 63 and pinion 65 are not engaged, and the rack 62 and pinion 64 are also not engaged. on the other hand,
In FIG. 7, when the pallet 4 is clamped, the rack 63 and pinion 65 are engaged, and the rack 62 and pinion 64 are also engaged.

In FIG. 6, the rod 5 of the clamp cylinder 51 is
2 is contracted, and the clamp plate 53 clamps the pallet 4 to the pins 80 and 81. The workpiece 75 is clamped in this manner when the workpiece 75 is processed by the tool 23 (see FIG. 2).

In FIG. 6, the clamp plate 53 unclamps the pallet 4 by extending the rod 52 of the clamp cylinder 51 upward. At the same time, as shown in Fig. 7, the pinion 6
4 meshes with rack 62. The pinion 65 also meshes with the rack 63. This unclamping is performed when the pallet 4 is transferred from the table 2 to the pallet stand (see FIG. 2).

Please refer to FIG.

In FIG. 8, the above-mentioned pins 80 and 81 are provided on the slide portion 50 of the table 2. These pins 80 and 81 function as a seating surface for the pallet 4 and as positioning pins. That is, when the pallet 4 is in the fixed position on the table 2, the pins 80,
The upper ends of 81 are adapted to fit into shallow holes 56a of parts 56, 56, respectively. The slide portion 50 is movable along the rails 70, 71 of the saddle 8.

In FIG. 9, the pallet 4 is positioned on the pallet stand 30. In this case, the table 2 has moved to the right end of the saddle 8. A pinion 65 of the moving mechanism 12 is engaged with the left end or tip of the rack 63. Further, the pinion 64 is engaged with the right end or tip of the rack 62.

In FIG. 9, the servo motor 10 is operated to move the table 2 in the first direction X1. This table 2 and gear housing 61 always move in one direction X1. In this case, as shown in FIG. 7, the pallet 4 is of course in an unclamped state, and the pinion 64 and rack 62 are engaged, and the pinion 65 and rack 63 are also engaged. In Figure 9, table 2 is in one direction.
Moving to X1 means that the table 2 moves downward perpendicularly to the plane of the paper in FIG. Therefore, the pinion 64 rotates in the r1 direction while meshing with the rack 62. This rotation causes the pinion 65 to rotate in the r2 direction. This rotation of the pinion 65 causes the pallet 4 to slide into the sliding portion 5 of the table 2.
It moves on the table 2 in the same direction as 0, that is, one direction X1 (see FIG. 9).

This results in the state shown in FIG. 10.
That is, the pallet 4 is set at a fixed position on the table 2.

Referring again to FIG. 6, the clamp cylinder 5
1 rod 52 is shortened and pallet 4 is made into table 2
Clamp on. This causes the pinion 64 to separate from the rack 62. In this state, the workpiece 5 will be processed.

This processing is carried out in a conventional manner using the tool 23 shown in FIG. For example, drill a hole in workpiece 5.

Referring again to FIG. 7, after processing the workpiece 5, the rod 52 of the clamp cylinder 51 is extended to release the clamp on the pallet 4. This causes the pinion 64 to engage the rack 62 again.

Refer now to FIG. The servo motor 10 is driven to move the table 2 in the other direction X2.
In this case, as shown in FIG. 7, the pallet 4 is in an unclamped state, the pinion 64 and the rack 62 are engaged, and the pinion 65 and the rack 63 are
They are also interlocking. In FIG. 10, the table 2 moves in the other direction X2, which means that in FIG. 7, the table 2 moves to the front perpendicular to the plane of FIG. Therefore, the pinion 64 is easy to use.
At 2, it rotates in the r3 direction. Therefore, the pinion 65 rotates in the r4 direction. For this reason, palette 4
It also moves on the table 2 in the same direction as the slide portion 50 of the table 2, that is, in the other direction X2 (see FIG. 10). As a result, when the table 2 moves to the right end of the saddle 8 as shown in FIG. 9, the pallet table 4 is moved onto the pallet stand 30 again.

In this way, the pallet 4 can be set on the table 2, the workpiece 5 can be processed, and the pallet 4 can be transferred from the table 2 in this order.

Next, the settings of palettes 4 and 14 in table 2 will be explained with reference to FIGS. 11 to 17.

In FIG. 11, both pallets 4 and 14 are on the pallet stand 30, and the table 2 is in its original position.
It is set to IP. Table 2 is in the other direction
Move to X2, then move to Y1 direction.

As a result, table 2
The pinion 65 of the pallet 4 engages with the tip of the rack 63 of the pallet 4. Then move table 2 in one direction.
Move to X1.

Referring to FIG. 13, palette 4 is set on table 2. The table 2 is located at a processing position P1. At this time, the spindle head 21 shown in FIG. 2 is lowered and a hole H is formed in the workpiece 5 using the tool 23.

Referring to FIG. 14, after processing, the table 2 is moved to another position SP. The table 2 then moves in the other direction X2. At this time, as the table 2 moves, the pallet 4 also moves on the table 2 in the other direction X2.

Referring to FIG. 15, the pallet 4 is returned to the pallet stand 30.

Please refer to FIG. Move table 2 in the Y2 direction. This causes the pinion 65 of table 2 to
Remove it from rack 63 and engage it with rack 91. Then, table 2 is moved in one direction X1. At this time, as the table 2 moves, the pallet 14 also moves on the table 2 to one side X1.

Refer to FIG. 17. Processing position of table 2
Move to P1, lower the spindle head 21 shown in FIG. 2, and process the workpiece 5 with the tool 23.

In this way, pallets 4 and 14 become table 2.
The workpieces 5 and 5 are machined in this order.

However, the present invention is not limited to the embodiments described above. In the above-mentioned vertical machining center, a plurality of pallets are installed on a pallet stand next to the machining center. In this case, by moving the table in the X-axis direction, a plurality of pallets can be exchanged. On the other hand, a plurality of pallets may be set on the pallet stand at the front side of the vertical machining center via the pallet stand. In this case, a plurality of pallets are exchanged by moving the table in the Y-axis direction.

Furthermore, a pallet stand may be placed next to the horizontal machining center, and a plurality of pallets may be installed on this pallet stand. In this case, a plurality of pallets can be exchanged by moving the table in the X-axis direction. Furthermore, a pallet stand may be placed in front of the horizontal machining center, and a plurality of pallets may be installed on this pallet stand. In this case, a plurality of pallets can be exchanged by moving the table in the Z-axis direction.

Further, the number of pallets is not limited to two, but may be more than two.

Further, the pallet changing device of the present invention can be used not only for the above-mentioned machine tools but also for general industrial machines such as automatic tool assembly machines using X and Y tables.

Further, in the illustrated embodiment, the table 2 is moved in the Y-axis direction so that the table 2 corresponds to the pallets 4 and 14 in sequence. However, the pallets 4 and 14 on the pallet stand 30 may be moved relative to the table 2 (in the Y-axis direction).

Effects of the Invention As is clear from the above explanation, since the pallet is moved in the same direction as the table via the moving mechanism using the driving force of the table driving means, a separate large hydraulic cylinder or large motor is not required. It is not necessary, and the structure can be simplified due to its small size. And significant cost reductions can be achieved.

Furthermore, by configuring the table drive means with a servo motor and a ball screw operated by this servo motor, the speed of pallet exchange can be freely accelerated or decelerated, and there is no shock when starting and stopping, and pallet settings and changes can be made. You can improve your speed.

If the moving mechanism is provided with a rack and pinion and the rack and pinion are mechanically disengaged when the pallet is clamped to the table, the position of the pallet relative to the table will not shift even if the table is moved during processing. Also, no load is placed on the feed screw. Therefore, there is no need for a limit switch for interlock, and the electric circuit can be simplified.

[Brief explanation of drawings]

Fig. 1 is a schematic diagram showing a pallet changing device of the present invention, Fig. 2 is a front view showing a machining center equipped with the pallet changing device of the present invention, Fig. 3 is a side view of the machining center, and Fig. 4 is a diagram showing a pallet stand. 5 is a perspective view showing the pallet table, FIG. 6 is a sectional view taken along line A-A in FIG. 2 showing the state in which the pallet is clamped to the table, and FIG. A- in Figure 2 shown
Fig. 8 is a sectional view taken along line B-B in Fig. 2, Fig. 9 is a front view showing the state where the pallet is not placed on the table, and Fig. 10 shows the state where the pallet is set on the table. Front view, 11th
17 to 17 are diagrams showing the pallet exchange operation. PC...Pallet exchange device, 1...Support part, 2
... table, 3 ... drive means, 4, 14 ... workpiece conveyance pallet, 5 ... workpiece, 6 ... machining center, 7 ... bed, 8 ... saddle,
9, 10... Servo motor, 12... Movement mechanism,
20...Column, 21...Spindle head, 2
3... Tool, 30... Pallet stand, 50... Slide part, 51... Clamp cylinder, 53...
Clamp plate, 61...Gear housing, 6
3,91...Rack, 64,65...Pinion,
66...Gear.

Claims (1)

[Claims] 1. A support part 1; a table 2 set on the support part 1 and movable in at least one axis (for example, the X axis); and a table 2 that is detachable from the table 2 and movable on the table 2. A workpiece conveyance pallet 4 set to
Another pallet 14 for transporting workpieces located at a different location from the table 2; a driving means 3 equipped with something like a servo motor for moving the table 2 along one axis (for example, the X axis); and the table 2. A moving mechanism that moves the workpiece conveying pallet 4 on the table 2 in one direction or the other direction by the driving force of the driving means 3 when the workpiece is moved in one direction or the other direction of one axis (for example, the X axis) 12, the workpiece conveying pallet 4 is transferred using only the drive means 3, no drive means such as a hydraulic cylinder or a motor is required other than the drive means 3, and the moving mechanism is fixed to the support part side. It is equipped with a rack and a pinion configured to engage with the rack while moving in one direction or the other direction in conjunction with the table. A pallet exchange device characterized by a structure in which a rack and a pinion engage when unclamped. 2. The driving means includes a ball screw section operated by a servo motor, a nut of the ball screw section is fixed to a table, and a feed screw of the ball screw section is connected to the servo motor. The pallet changing device described in section. 3. The pallet exchange device according to claim 1, wherein the table is movable in another axial direction orthogonal to the one axial direction.