JPH0366430A - Work holding device in plate material working machine - Google Patents

Abstract

PURPOSE:To improve the machining accuracy of the work and the working efficiency by holding the work with the single cylinder mounted on the work clamp at the position where the work clamp is advanced against the work and releasing holding of the work when it retreats from the work. CONSTITUTION:The laser beam machine 1 has the laser oscillator 3 and projects the generated laser beam LB from the nozzle head 5. The work holding device is constituted to arrange plural work clamps 11 which hold the work W and guide it to the X-axial direction. The work is cut into the two-dimentional shape with the laser beam LB from the nozzle head 5. The work holding timing and the retreating start timing are operated automatically with the accurate time difference by operating the advancing and retreating of the work clamp and the holding and releasing of the work with the single cylinder part C as for the work clamp of the part which is positioned in the interferencial area. The damage of the work caused by malfunction and the trouble of the work clamp in itself are prevented and the working efficiency is improved.

Description

[Detailed Description of the Invention] [Object of the Invention] (Industrial Application Field) The present invention relates to a work gripping device for a plate processing machine.

(Prior Art) Generally, a workpiece and a processing section of a plate processing machine are configured to move relative to each other, so there is a problem that the workpiece clamp of a workpiece gripping device and the processing section interfere with each other. Conventionally, in order to avoid such interference, the work clamp was configured to automatically retreat from the machining area, that is, the interference area, as disclosed in Japanese Patent Publication No. 60-146644 and Japanese Patent Publication No. 60-60.
There are 170539@ etc. In these technologies, a cylinder that clamps or releases the workpiece and a cylinder that moves the workpiece clamp forward and backward are provided separately, and after confirming that the workpiece clamp is released from the workpiece, the workpiece clamp is moved back or rotated to escape from the interference area. However, on the contrary, the workpiece is clamped only after confirming that the workpiece clamp has moved forward or rotated.

For example, in a plate processing machine that performs thermal cutting, etc., when machining is performed continuously near the workpiece clamp, only a specific workpiece clamp that approaches the machining interference area out of multiple workpiece clamps is automatically released. By retreating and retracting the workpiece, the other workpiece clamps continue to clamp the workpiece, thereby enabling efficient continuous work without deteriorating machining accuracy due to re-gripping the workpiece, etc.

(Problem to be Solved by the Invention) However, the workpiece gripping device according to the above method includes a cylinder that clamps or releases the workpiece by a workpiece clamp,
The cylinder that moves the work clamp forward and backward is operated separately. For this reason, the workpiece clamp must either move back after receiving an IR that it has been released from the workpiece, or conversely clamp the workpiece after confirming that the workpiece clamp has completed forward movement. Therefore, the work clamp is likely to malfunction if there is no time lag between the time it completes advancing until it clamps the work and the time it releases the work until it starts moving back. However, for this reason, a detection device is required to check the time difference between workpiece clamps to prevent malfunctions. As a result, the detection device and its operating circuit, and the plurality of cylinders and their operating circuits that move the work clamp back and forth, clamp or release the workpiece,
Work grip f! There are problems in that the configuration of the device becomes complicated, efficiency is hindered due to the extra time required to confirm the time difference in the operation of the workpiece clamp, and the manufacturing cost of the device increases.

Therefore, the present invention provides a plate processing machine that simplifies the configuration of a workpiece gripping device, prevents workpiece clamp malfunctions, and eliminates the need to take time to check the time difference between workpiece clamp operations, thereby improving work efficiency. The object of the present invention is to provide a workpiece gripping device.

[Configuration of the Invention (Means for Solving the Problems) In order to achieve the above object, the present invention provides a workpiece that is held between the workpieces and processed by a processing section while moving on the upper surface of the worktable. A workpiece gripping device equipped with a clamp grips the workpiece at a position where the workpiece clamp is advanced relative to the workpiece by a single cylinder provided on the workpiece clamp that operates in the front-rear direction, and the workpiece is A workpiece gripping device for a plate processing machine is constructed by providing a differential device within the workpiece clamp that moves the workpiece backward after releasing the workpiece when the workpiece is moved backward.

(Operation) The workpiece supplied to the top surface of the worktable is held by the workpiece clamp and processed by the machining section while being moved.During the movement of the workpiece by the workpiece clamp, some of the workpiece clamps touch a part of the machining section. When approaching a workpiece clamp that becomes an obstacle to continuous machining movement, the differential position of the work clamp of the part that becomes an obstacle is activated. After the workpiece is released from the clamping position by the backward movement, the workpiece clamp is moved backward from the workpiece and the workpiece clamp is evacuated from the obstacle.When the evacuation of this obstacle is completed, the forward movement of the cylinder is performed. The workpiece clamp is moved forward relative to the workpiece and returned to the original clamping position, and then the workpiece clamp is used to clamp the workpiece.While the workpiece clamp is releasing the clamping position, It is moved together with other clamping workpiece clamps.

(Example) Hereinafter, an example in which the present invention is applied to a laser processing machine will be described in detail.

7 and 8, the laser processing machine 1 has a laser oscillator 3 on the upper side of the machine body, and a laser beam LB generated by the laser oscillator 3 is transmitted through pend mirrors M1, M2, M3, and M4. The laser beam LB is sent to a nozzle head 5 having a built-in condensing lens through the nozzle, and a laser beam LB can be oscillated from the tip nozzle of the nozzle head 5.

In Fig. 7, below X in the left and right direction of the work table 7
(referred to as the axial direction), there is an
An X is provided. The X-axis carriage 9 is guided in the X-axis direction by screwing an X-axis screw SX extending parallel to the X-axis guide RX into a nut member (not shown) and rotationally driving the X-wheel motor MX. It is configured to be

A plurality of workpiece clamps 1111 that clamp and guide the workpiece W in the X-axis direction are fixedly arranged at predetermined intervals along the X-axis carriage 9 to constitute a workpiece gripping device.

As shown in FIG. 8, a gate-shaped frame 13 is provided above the work table 7 on the machine body, and the upper part of this frame 13 has a Y axis extending in the front-rear direction (hereinafter referred to as the Y-axis direction). A shaft rule RY is provided. Similarly to the X-axis direction, the Y-axis carriage 15 is constructed by screwing a Y-axis screw SY extending parallel to the Y-axis rail RY into a nut member (not shown) and rotationally driving a Y-axis servo motor MY. X
It is configured to guide in the Y-axis direction perpendicular to the axis. The Y-axis carriage 15 includes a two-axis rail R.
A Z-axis carriage 17 that is guided in the vertical direction (hereinafter referred to as the Z-axis direction) via Z is provided, and the nozzle head 5 is attached to this Z-axis carriage 17. Note that the two-axis carriage 17 is driven in the two-axis directions by screwing a Z-axis screw SZ extending parallel to the Z-axis lever RZ into a nut member (not shown), as in the X-axis and Y-axis directions. It is configured to rotationally drive a two-axis servo motor MZ.

Therefore, as shown in FIG. 7, the laser processing machine 1 shown in this example uses the laser beam LB from the nozzle head 5 to guide the workpiece W in the X-wheel direction to the desired two-dimensional shape. Can be cut into shapes.

In FIG. 7, in order to detect that the nozzle head 5 approaches the work clamp 11, the frame 1
Y-axis sensor 1 is located at the position of work clamp 111F of No. 3.
9 is provided, and the Y-axis dog 2 is mounted on the Y-axis carriage 15.
1 is provided. Further, as shown in FIG. 8, in order to detect the approach of the nozzle head 5 during movement in the X-axis direction, each workpiece clamp 11.11 is provided with an X-axis sensor 23, and this An X-axis dog 25 is provided on the work table 7 at a position where the sensor 23 passes w3It. Therefore, in this example, work clamp 1
Under the condition that the X-axis sensor 23 provided in 1 has detected the X-axis dog 25 and that the Y-axis sensor 19 has detected the Y-axis dog 21, the interference area is known, and each workpiece clamp 11.11 is separately detected. I'm trying to retreat and evacuate. In addition, the X axis.

If the Y-axis is numerically controlled, the interference area is known, so the sensors and dogs can be omitted.

Details of the work clamp 11 are shown in FIGS. 1, 2, and 3.

The workpiece gripping device is constructed by fixing a plurality of workpiece clamps 11 11 to an X-axis carriage 9 and a clamp body 27 of each workpiece clamp 11 . The work clamp 11 has an upper clamp claw 29 and a lower clamp claw 3.
1. The lower clamp claw 31 is attached to the side body 3
3, and the upper clamp claw 29 is provided so as to be movable up and down about a fixed pin 35 with respect to the side body 33. Further, the side body 33 is configured to be movable while being guided by guide shafts 37, 37 extending in the Y-axis direction. Further, the slider 39 is configured to be loosely fitted into the side body 33 and movable in the Y-axis direction using a guide pin 41.41 fixed to the side body 33 along the Y@ direction and a guide shaft 37.37 as guides. has been done.

Further, a piston 43 is fitted into a cylinder portion C provided on the slider 39, one end portion of this piston 43 is fixedly provided on the clamp body 27, and this piston 43 receives a supply of pressure fluid such as compressed air. The slider 39 is actuated to move the slider 39 forward against the piston compression spring 45. As the slider 39 moves forward, the side body 33 is moved forward by the elastic force of slider compression springs 47, 47, which are elastically attached to the guide bins 41, 41, respectively. Also, the pressure fluid is in the cylinder part C.
When ejected from the piston 43, the piston compression spring 4
5 causes the slider 39 and the side body 33 connected to the slider 39 by a guide bin 41 and a slider compression spring 47 to retreat.

Note that the piston compression spring 45 is spring-loaded between the piston 43 and the rear receiving plate of the slider 39.

Further, the clamping opening/closing of the upper clamp claw 29 is carried out by moving the slider 39 forward and pushing up the rear end of the clamp upper claw 29 with the tips of the three sliders. 35 as a support shaft, and as a result of this pushing down, the workpiece W is clamped between the lower clamp claw 31 and the lower clamp claw 31. Further, the workpiece W is released from being held by retracting the slider 39.

As shown in FIG. 3, the work clamp 11 is equipped with a position detection sensor 49 and a position detection dog 51 on the clamp body 27 and slider 39, respectively, in order to detect the advancing state of the slider 39 and obtain the next control signal. It is provided. Further, in order to prevent the workpiece W from buckling during machining, a lifting guide shaft 53 in the Z-axis direction is provided so that the clamp body 27 can move up and down. Further, a joint 55 for supplying pressure fluid to the cylinder portion C of the slider 39 from the outside is provided on the upper part of the clamp body 27. 57, 59, 61 are the bushings of each guide shaft 37, 53.

According to the above configuration, the work clamp 11 detects the interference area by the X-axis sensor 23 and dog 25 and the Y-axis sensor 19 and dog 21 shown in FIGS. 7 and 8, or detects the interference area from the numerical control section. With this command, it is possible to detect the interference area and retreat to the retracted state shown in FIG.

In FIGS. 1 and 4 to 6, when holding the workpiece W, by supplying fluid to the cylinder portion C in FIG.
The slider 39 moves forward due to the operation of the piston 43, and the slider compression spring 47 moves forward as the slider 39 moves forward.
The side body 33 is moved forward in conjunction with the clamp body 27 via the clamp body 27 (FIG. 5). After the side body 33 moves forward and is prevented from moving forward by the stopper 63 at the tip of the clamp body 27, only the slider 39 continues to move forward while compressing the slider compression spring 47 (sixth
figure). As the slider 39 moves forward, the rear ends of the two upper clamp jaws are pushed up, and the tips are pushed down in a see-saw manner with the bin 35 as a fulcrum, and the workpiece W is pressed with a pressing force F between the lower clamp jaws 31. (See Fig. 2) In addition, as described above, the work clamp 11 detects that it has approached the interference area, and by discharging the fluid from the cylinder portion C, the work clamp 11 is clamped by the interaction between the piston compression spring 45 and the slider compression spring 47. At first, only the slider 39 is retracted by 11 degrees (Fig. 6 → Fig. 5), and this retraction releases the clamping force of the workpiece W by the upper clamp claw 29. After that, the slider 39 is also retracted by the action of the piston compression spring 45. (Fig. 4), the compression of the slider compression spring 47 is released, and the side body 33 is moved backward by the guide bin 41 to avoid interference with the nozzle head 5. Nozzle head 5
If it leaves, it will perform the opposite action again and return. That is, the action of the piston 43 returns the claws of the side body 33 to the original clamping position via the slider 39, and the workpiece W is clamped with a pressing force F.

In this way, while some of the workpiece clamps 11 in the workpiece gripping device that have detected the approach of an obstacle release the workpiece W, the remaining workpiece clamps 11 are used to hold the workpiece W. Processing using the laser beam LB from the nozzle head 5 is continued while the W is held in the sandwiched state and moved relative to the nozzle head 5. Further, at this time, the workpiece clamp 11 that avoids this obstacle is released from clamping the workpiece W, but is controlled to move integrally with the X-axis carriage 9.

The explanation of the *example above is based on the case where the work clamp 11 is moved in the X-axis direction by the X-axis carriage 9, but it may also be configured to move in the Y-axis direction. It may also be configured. Further, the work clamp 11 may be provided with a plurality of work gripping devices in multi-axis directions, and in short, the present invention is capable of retracting each work clamp 11 when it approaches the interference area, and moving away from the interference area. Since the structure is such that it returns to its original state again, the same effect can be achieved. Note that the evacuation configuration shows an example in which the slider 39 is used to move linearly, but for example,
It can also be configured to rotate using a cam, a cam follower, or the like.

Note that this invention is not limited to the above-mentioned embodiments (
However, by making appropriate changes, it can be implemented in other ways.

[Effects of the Invention] As explained above, according to the workpiece gripping device of the plate processing machine of the present invention, in the workpiece clamp located in the interference area, the workpiece clamp can be moved forward and backward, and the workpiece can be clamped or released. By using a single cylinder, it is possible to adjust the timing of clamping the workpiece after completion of forward movement and the timing of starting retreat after releasing clamping of the workpiece, in relation to the forward or backward movement of the workpiece clamp due to approach or separation of the interference area. They can be automatically linked and operated with precise time differences.

This prevents damage to the workpiece due to malfunction of the workpiece clamp and failure of the workpiece clamp itself, ensuring machining accuracy and work efficiency of the workpiece, and continuing smooth machining work.

[Brief explanation of drawings]

Fig. 1 shows the main parts of the present invention, and Fig. 7 is an enlarged plan view of the work clamp section in the inventive view section, Fig. 2 is a sectional view taken along the line ■-■ in Fig. 1, and Fig. 3 is a cross-sectional view of the ■−■ of the diagram
4 to 6 are working cross-sectional mechanical diagrams showing the operation process of the work clamp section, FIG. 7 is a plan view of a laser processing machine which is an example of a plate processing machine, and FIG. 8 is a 2 is a right side view in FIG. 1. FIG. 1... Laser processing machine 3... Laser oscillator 5... Nozzle head 7... Work table 9... X-axis carriage 11... Work clamp 13... Frame 15... Y-axis carriage 17... Z-axis carriage 27... Clamp body 29... Clamp upper claw 31... Clamp lower claw 33... Side body 39... Slider C... Cylinder part W... Work

Claims (1)

[Claims] A workpiece gripping device equipped with a workpiece clamp that holds a workpiece and causes the workpiece to be processed by a processing section while moving on the upper surface of the worktable, and a single cylinder provided on the workpiece clamp that operates in the front and back direction, A differential device is provided in the work clamp, which clamps the work at a position where the work clamp is advanced relative to the work, and when retracting from the work, releases the grip on the work and then moves the work backward. Features a workpiece gripping device for plate processing machines.