HK1201786B - Laser processing machines - Google Patents

Description

Sheet holding device

Technical Field

The present invention relates to a thin plate holding device in a laser processing machine that performs processing by irradiating a thin plate serving as a workpiece with laser light.

Background

A laser beam machine is used for fine processing of a workpiece formed of a metal thin plate. The laser beam machine is configured to stretch a thin plate on an XY stage which moves in a plane in a direction perpendicular to an optical axis of a laser beam, move the thin plate in XY directions by the XY stage, and cut the thin plate by irradiating the laser beam condensed by a processing head. When cutting a thin plate with high precision and high quality, the laser beam is focused on the thin plate as small as possible so that the focal position does not change, and an assist gas is injected into the thin plate (processing portion). By injecting the assist gas into the thin plate, it is possible to blow off molten material or the like scattered from the cut portion of the thin plate at the time of laser processing.

However, there is a problem that local deflection (wrinkles) occurs in the sheet due to the injection pressure of the assist gas, and the focal point of the laser light fluctuates. To solve this problem, it is effective to hold the sheet in tension on the XY table to overcome the ejection pressure of the assist gas.

However, there is a problem that it is difficult to hold the thin plate on the XY stage while applying a tension to the thin plate that overcomes the ejection pressure of the assist gas, and skill is required.

Disclosure of Invention

The present invention has been made to solve the above-described problems, and an object of the present invention is to provide a sheet holding device capable of setting a sheet on an XY table with a simple operation.

In order to achieve the object, a thin plate holding device according to claim 1 is a thin plate holding device in a laser processing machine, the laser processing machine including: a processing head which irradiates a laser beam to a thin plate to be processed and injects an assist gas; and an XY table which moves in a plane in a direction perpendicular to an optical axis of the laser light irradiated from the processing head, wherein a1 st frame member and a 2 nd frame member are fixed to the XY table so as to face each other with a predetermined distance therebetween. A1 st member is disposed between a1 st frame member and a 2 nd frame member, and one end of the thin plate is held between the 1 st member and the 1 nd member. The 2 nd member is configured to be relatively movable in a direction away from the 1 st member, and the 2 nd member is disposed between the 1 st frame member and the 2 nd frame member along the 2 nd frame member. The other end of the thin plate is held by the 2 nd member.

One ends of a plurality of links formed so as to be capable of swinging within a plane intersecting the optical axis are coupled to a plurality of portions of the 2 nd member, and the other ends of the links are coupled to a tension applying mechanism. The tension applying mechanism applies a force to the 2 nd frame member from the 2 nd member, thereby applying a tension to the sheet clamped by the 1 st member and the 2 nd member at both ends, so that the sheet can be arranged on the XY table by a simple operation.

The thin plate holding device according to claim 2 is a thin plate holding device in a laser processing machine, the laser processing machine including: a processing head which irradiates a laser beam to a thin plate to be processed and injects an assist gas; and an XY table which moves in a plane in a direction perpendicular to an optical axis of the laser light irradiated from the processing head, wherein a1 st frame member and a 2 nd frame member are fixed to the XY table so as to face each other with a predetermined distance therebetween. A1 st member is disposed between a1 st frame member and a 2 nd frame member, and one end of the thin plate is held between the 1 st member and the 1 nd member. The 2 nd member is configured to be relatively movable in a direction away from the 1 st member, and the 2 nd member is disposed between the 1 st frame member and the 2 nd frame member along the 2 nd frame member. The other end of the thin plate is held by the 2 nd member.

One end of the linear member is connected to the 2 nd member, and the other end is connected to the 1 st member. Since the linear member is wound around a wheel rotatably supported by the 1 st member, the 1 st member and the 2 nd member can be relatively moved at an intermediate position between the 1 st frame member and the 2 nd frame member. Since the 2 nd member is urged to the 2 nd frame member by the tension applying mechanism to apply tension to the sheet sandwiched between the 1 st member and the 2 nd member at both ends, it is possible to provide the sheet on the XY table by a simple operation.

The thin plate holding device according to claim 3 is a thin plate holding device in a laser processing machine, the laser processing machine including: a processing head which irradiates a laser beam to a thin plate to be processed and injects an assist gas; and an XY table which moves in a plane in a direction perpendicular to an optical axis of the laser light irradiated from the processing head, wherein a1 st frame member and a 2 nd frame member are fixed to the XY table so as to face each other with a predetermined distance therebetween. A1 st member is disposed between a1 st frame member and a 2 nd frame member, and one end of the thin plate is held between the 1 st member and the 1 nd member. The 2 nd member is configured to be relatively movable in a direction away from the 1 st member, and the 2 nd member is disposed between the 1 st frame member and the 2 nd frame member along the 2 nd frame member. The other end of the thin plate is held by the 2 nd member.

Since the support rod is disposed between the 2 nd member and the 1 st member and the lower surface of the thin plate sandwiched between the 1 st member and the 2 nd member at both ends is supported by the support rod, the thin plate can be prevented from being deflected downward by its own weight. Since the 2 nd member is urged to the 2 nd frame member by the tension applying mechanism to apply tension to the sheet sandwiched between the 1 st member and the 2 nd member at both ends, it is possible to provide the sheet on the XY table by a simple operation.

According to the thin plate holding apparatus of claim 4, in addition to the effects achieved by any one of claims 1 to 3, the thin plate elastically deformed at a predetermined deformation ratio can be laser-processed, and the processing accuracy of the thin plate can be improved.

That is, when the thin plate tensioned during the laser processing is released from the tension after the laser processing, the thin plate returns to the state before the tension. When the thin plate is elastically deformed at a predetermined deformation ratio by applying tension, the thin plate elastically restored after releasing the tension can be processed to a target size by performing laser processing based on a corrected size obtained by multiplying the target size by the deformation ratio.

In the holding device, the 3 rd frame members, both ends of which are fixed to the 1 st and 2 nd frame members, are opposed to each other with a predetermined distance therebetween, and both ends of the lateral member are fixed to the 3 rd frame member. The transverse member is arranged side by side with the 1 st member, and the transverse member and the 1 st member are fastened by means of a fastening member. Thus, when the 2 nd member is relatively moved in a direction away from the 1 st member after both ends of the thin plate are sandwiched between the 1 st member and the 2 nd member, tension is applied to both ends of the thin plate, and the thin plate can be elastically deformed at a predetermined deformation ratio and tensioned. As a result, the tensioned thin plate can be elastically deformed so as to be prevented from being twisted, and can be elastically deformed at a predetermined deformation ratio, and therefore, by performing laser processing based on a correction dimension obtained by multiplying the target dimension by the deformation ratio, processing according to the target dimension can be performed on the thin plate after the tensioning is released. This has the effect of improving the processing accuracy of the thin plate.

According to the thin plate holding device of claim 5, the fastening members and the tension applying mechanisms are disposed at a plurality of positions of the 1 st member and the 2 nd member at the following positions: a plurality of straight lines connecting the fastening position in the 1 st member of the fastening member and the coupling position in the 2 nd member of the tension applying mechanism are parallel. Thus, when tension is applied to the sheet by the tension applying mechanism, the sheet can be urged in a direction parallel to the direction connecting the fastening member and the tension applying mechanism. As a result, in addition to the effect of claim 4, there is an effect that the machining accuracy can be improved.

According to the thin plate holding device of claim 6, since the lateral members are arranged on the side of the 1 st member away from the 2 nd member in parallel in the plane where the 1 st member and the 2 nd member are located, the rigidity of the 1 st member and the lateral members can be increased with respect to the direction of the force acting when the thin plate is tensioned.

Further, by aligning the direction of the force acting when the thin plate is tensioned with the axis of the fastening member, it is possible to prevent the bending stress from acting on the fastening member and increase the rigidity of the 1 st member and the lateral member. As a result, the deformation of the 1 st member and the lateral members can be suppressed, and the tension can be uniformly applied to the thin plate. As a result, in addition to the effect of claim 5, there is an effect that the machining accuracy can be improved.

According to the thin plate holding device of claim 7, the thin plate is mounted on the mounting surfaces of the 1 st member and the 2 nd member. The movement of the sheet loaded on the loading surface is regulated by wall parts erected on the 1 st frame member side and the 2 nd frame member side, respectively. In a state before the 2 nd member is relatively moved in a direction away from the 1 st member, the distance between the lower end portions of the wall portions is set to be larger than the maximum value of the dimensional tolerance of the sheet, so that even if the size of the sheet varies to the maximum value side within the tolerance range, the end portions of the sheet mounted on the mounting surface can be prevented from touching the wall portions. Thus, the thin plate can be clamped between the 1 st clamping part and the 2 nd clamping part without generating looseness on the thin plate, and sufficient tension can be stably applied to the thin plate by tensioning the thin plate. This has an effect of improving the machining accuracy in addition to the effect of any of claims 1 to 3.

According to the thin plate holding device of claim 8, the upper step portion provided in connection with the upper ends of the wall portions of the 1 st member and the 2 nd member and the mounting surface are formed in a stepped shape, and one end side of the urging member is disposed at the upper step portion. The pressing members facing each other in the longitudinal direction of the loading surface are biased upward by the biasing member and spaced apart from the loading surface by a predetermined distance, so that the thin plate can be inserted into the gap.

Further, since the one end side of the urging member is disposed in the upper step portion formed in a stepped shape with respect to the loading surface via the wall portion, when the thin plate is inserted between the loading surface and the pressing member, the thin plate is blocked by the wall portion and does not reach the urging member. This prevents the urging member from touching and damaging the end of the thin plate. Further, the pressing surface of the pressing member is pressed against the sheet loaded on the loading surface by the fastener which lowers the pressing member against the urging force of the urging member, and thus the sheet can be held.

Further, since the pressing surface of the pressing member is formed longer than the width of the thin plate in the direction perpendicular to the relative movement direction of the 2 nd member, the entire width of the thin plate can be pressed by a single pressing member. As a result, in addition to the effect of claim 7, there is an effect that the processing accuracy can be improved by preventing the deviation of the elastic deformation amount of the thin plate in the entire longitudinal direction of the pressing member.

According to the thin plate holding device of claim 9, since the upper sides of the wall portions protrude toward the processing head with respect to the lower sides, the leading end of the thin plate inserted between the loading surface and the pressing surface is received in the loading surface in contact with the wall portions, and the thin plate holding device can be prevented from passing over the wall portions. This has an effect of preventing the thin plate sandwiched between the mounting surface and the pressing surface from being bent at the wall portion, in addition to the effect of claim 8.

According to the thin plate holding apparatus described in claim 10, since the movement of the 2 nd member relative to the 1 st member is restricted by the movement restricting mechanism against the urging force by the tension applying mechanism, the amount of extension of the thin plate in the process of cutting the thin plate can be restricted.

That is, in the laser processing, the sectional area of the thin plate is reduced as the thin plate is cut. If the biasing force by the tension applying mechanism is constant, the stress increases as the cross-sectional area of the thin plate becomes smaller, and the amount of extension of the thin plate increases without the movement restricting mechanism. This reduces the processing accuracy of the thin plate.

In contrast, by restricting the relative movement of the 2 nd member with respect to the 1 st member by the movement restricting mechanism, even if the thin plate is cut and the cross-sectional area of the thin plate is reduced, the thin plate can be held in tension and the amount of extension of the thin plate can be restricted. This has an effect of improving the machining accuracy in addition to the effect of any of claims 1 to 3.

Drawings

Fig. 1 is a front view of a laser beam machine according to embodiment 1.

Fig. 2 is a plan view of the thin plate holding device.

Fig. 3 is a plan view of the thin plate holding device in embodiment 2.

Fig. 4 is a partially enlarged plan view of the holding device.

Fig. 5 is a cross-sectional view of the holding device of fig. 4 taken along line V-V.

Fig. 6 (a) is a cross-sectional view of the holding device taken along line VI-VI in fig. 4, and (b) is a partially enlarged cross-sectional view of the receiving member and the pressing member.

Fig. 7 (a) is a cross-sectional view of the holding device taken along line VIIa-VIIa in fig. 4, and (b) is a cross-sectional view of the pressing member and the receiving member when the fastener is released.

Fig. 8 is a plan view of the thin plate holding device of embodiment 3.

Fig. 9 is a cross-sectional view of the holding device of fig. 8 taken along line IX-IX.

Fig. 10 is an essential side view of the holding device as viewed from the arrow X direction of fig. 8.

Detailed Description

The best mode of the present invention will be described below with reference to the accompanying drawings. Fig. 1 is a front view of a laser processing machine 1 according to embodiment 1 of the present invention. As shown in fig. 1, the laser processing machine 1 mainly includes: a machining head 4 for irradiating a laser beam to a thin plate W to be machined and injecting an assist gas; the holding device 10 holds the thin plate W irradiated with the laser beam by the machining head 4. The machining head 4 for irradiating laser is suspended from the arm 2 via the horizontal movement member 3. The horizontal movement member 3 is configured to be movable in the Y direction with respect to the arm 2 by a Y-axis drive device 3a, while the machining head 4 is configured to be movable in the X direction with respect to the horizontal movement member 3 by an X-axis drive device 4 a. The machining head 4 is driven by the X-axis drive device 3a and the Y-axis drive device 4a to move in the XY direction with respect to the arm 2.

The machining head 4 introduces laser light through an optical fiber 6 connected to a laser oscillator 5. The laser beam is condensed by the condenser lens 7, and the sheet W is irradiated from the nozzle 9 at the lower end. The assist gas is supplied from the supply passage 9a to the processing head 4, and is ejected from the nozzle 9 toward the thin plate W. A protective cover 8 for protecting the condenser lens 7 from the injection pressure of the assist gas is disposed on the machining head 4. Since the laser beam is irradiated to the sheet W from the nozzle 9 at the lower end of the processing head 4 and the assist gas is injected, the molten material scattered from the cut portion of the sheet W during the laser processing can be blown off.

A holding device 10 for holding a sheet W is fixedly attached to an XY table 11 mounted to be movable in the XY direction with respect to a table (not shown). A machining table 12 is disposed inside the holding device 10 at a position facing the machining head 4. The processing table 12 is a member for supporting the sheet W from below and forming a passage for sucking the assist gas together with the melt of the sheet W to a suction device (not shown). The upper surface of the processing table 12 is set to a height that can slide on the lower surface of the sheet W held by the holding device 10. By supporting the thin plate W held under tension by the holding device 10 by the processing table 12, the thin plate W can be prevented from being deflected downward by the jet pressure of the assist gas.

The XY stage 11 to which the holding device 10 is fixed is a device for moving the holding device 10 in the XY direction, and a Y-axis driving device 11a and an X-axis driving device 11b are arranged. By driving and controlling the Y-axis driving devices 3a and 11a and the X-axis driving devices 4a and 11b by the control device 13, the machining head 4 and the holding device 10 (XY stage 11) are moved in the XY direction based on preset cutting data. This enables the cutting of the thin sheet W based on the cutting data set in advance in the control device 13.

Next, the holding device 10 for the thin sheet W will be described with reference to fig. 2. Fig. 2 is a plan view of the holding device 10 for the thin sheet W. In fig. 2, illustration of the XY table 11 to which the frame 20 is fixed is omitted. As shown in fig. 2, the holding device 10 includes a housing 20. The frame 20 is a member detachably fixed to the XY table 11, and is formed in a frame shape of a rectangular shape in plan view from the 1 st frame 21 and the 2 nd frame 22, and the 3 rd frame 23 that maintains the interval between the 1 st frame 21 and the 2 nd frame 22. A guide 24 is formed on the inner side surface of the 3 rd frame member 23 in the horizontal direction. The guide 24 is a portion for sliding the 1 st member 30 and the 2 nd member 40 along the 3 rd frame member 23.

The 1 st member 30 and the 2 nd member 40 are members for sandwiching both ends of the sheet W, and are disposed inside the frame 20 substantially in parallel with the 1 st frame member 21 and the 2 nd frame member 22, respectively. The support members 31 and 41 are members for placing the end portions of the thin plate W along the longitudinal direction, and slide members 31a and 41a fitted to the guide 24 of the 3 rd frame member 23 are attached to both ends of the support members 31 and 41. The support members 31, 41 are provided on their upper surfaces with pressing members 32, 42 for pressing the end portions of the sheet W from the upper surface, and fasteners 33, 43 for moving the pressing members 32, 42 toward (below) the support members 31, 41 to clamp the sheet W. The pressing members 32 and 42 can be moved up and down by operating the fasteners 33 and 43. The pressing members 32 and 42 are moved downward to clamp the sheet W, and the pressing members 32 and 42 are moved upward to release the sheet W.

Both end sides of the 1 st member 30 and the 2 nd member 40 are connected by a linear member 51 such as a wire or a chain. The linear member 51 having one end locked to the 2 nd member 40 extends toward the 1 st frame member 21, is wound around the wheel 50 rotatably supported by the 1 st frame member 21, and has the other end locked to the 1 st member 30. Thus, when one of the 1 st member 30 and the 2 nd member 40 is slid, the other of the 1 st member 30 and the 2 nd member 40 is interlocked and slid via the linear member 51. Since the length of the linear member 51 and the fitting positions of the sliding members 31a and 41a to the guide 24 are set so that the 1 st member 30 and the 2 nd member 40 can be brought close to the 1 st frame member 21 and the 2 nd frame member 22, respectively, and the 1 st member 30 and the 2 nd member 40 can be positioned at the substantially center in the longitudinal direction of the 3 rd frame member 23, the thin plate W can be held at the substantially center of the frame 20 by the 1 st member 30 and the 2 nd member 40.

The 2 nd member 40 is provided with: a tension applying mechanism 60 for applying tension to the thin sheet W held between the 1 st member 30 and the 2 nd member 40; and a movement limiting mechanism 70 for limiting the movement of the 2 nd member 40 toward the 2 nd frame member 22 by the tension applying mechanism 60. The tension applying mechanism 60 includes: a locking part 61 locked to the 2 nd member 40; a threaded rod 62 having one end fixed to the locking portion 61 and the other end penetrating the 2 nd frame member 22; and a biasing portion 63 that is screwed to the screw rod 62 to press the outer end surface of the 2 nd frame member 22, thereby biasing the engaging portion 61 and the 2 nd member 40 toward the 2 nd frame member 22. One tension applying mechanism 60 is disposed at each of positions symmetrical to a virtual line (not shown) passing through the center of the frame 20 in the width direction (vertical direction in fig. 2).

The movement restriction mechanism 70 includes: a pressing portion 71 for pressing the 2 nd member 40; a threaded rod 72 having one end fixed to the pressing portion 71 and the other end penetrating the 2 nd frame member 22; and a fixing portion 73 screwed to the screw rod 72 and abutting against the inner end surface of the 2 nd frame member 22, thereby fixing the gap between the 2 nd member 40 and the 2 nd frame member 22.

Next, a method of using the holding device 10 configured as described above will be described. The sheet W is cut into a minimum size in advance. The sheet W can be attached to the frame 20 in a state where the frame 20 is attached to the XY table 11. Further, since the frame 20 is detachable from the XY table 11, the frame 20 may be detached from the XY table 11 and the sheet W may be attached to the frame 20 at another place (any place as long as it is a flat surface). When a plurality of frames 20 are prepared, the thin plates W can be stretched in advance in a state where the frames 20 are removed from the XY table 11. When the thin plate W is stretched in advance in the plurality of frames 20, the laser processing of the thin plate W can be performed for each frame 20 by replacing the frame 20 fixed to the XY table 11.

To attach the thin plate W to the housing 20, first, the biasing portion 63 and the fixing portion 73 are rotated to loosen the screw, and the 2 nd member 40 is allowed to move relative to the 1 st member 30. Next, the 1 st member 30 and the 2 nd member 40 are moved in accordance with the length (the dimension in the left-right direction in fig. 2) of the sheet W. The fasteners 33, 43 are operated to form a gap between the support members 31, 41 and the pressing members 32, 42, and then one end side of the sheet W is inserted into the gap between the support member 31 and the pressing member 32, and then the fastener 33 is operated to clamp the sheet W by the support member 31 and the pressing member 32. Next, the other end side of the sheet W is inserted into the gap between the support member 41 and the pressing member 42, and then the fastening member 43 is operated to clamp the sheet W between the support member 41 and the pressing member 42.

Then, the biasing portion 63 is operated (rotated) to draw the locking portion 61 toward the 2 nd frame member 22. Thereby, the 2 nd member 40 is pulled toward the 2 nd frame member 22, and the 1 st member 30 and the 2 nd member 40 tension and hold the thin sheet W. Then, the fixing portion 73 is operated to bring the pressing portion 71 into contact with the outer end surface of the 2 nd member 40, thereby fixing the gap between the 2 nd member 40 and the 2 nd frame member 22. Thereafter, laser cutting processing is performed. After the laser cutting process is completed, the biasing unit 63 is operated to release the tension of the sheet W, and then the fasteners 33 and 43 are operated to release the state in which the sheet W is held between the support members 31 and 41 and the pressing members 32 and 42, and the processed sheet W is removed.

According to the holding device 10 for a thin sheet W configured as described above, since the 1 st member 30 and the 2 nd member 40 are coupled by the linear member 51 wound around the wheel 50 pivotally supported by the 1 st frame member 21, when the 2 nd member 40 is moved toward the 2 nd frame member 22, the 1 st member 30 is moved toward the 1 st frame member 21 in conjunction with this, and the interval between the 1 st member 30 and the 2 nd member 40 is widened. When the 2 nd member 40 is moved toward the 1 st frame member 21, the 1 st member 30 is moved toward the 2 nd frame member 22 in conjunction with this, and the interval between the 1 st member 30 and the 2 nd member 40 is narrowed. Accordingly, the 1 st member 30 and the 2 nd member 40 can be relatively moved at the intermediate position between the 1 st frame member 21 and the 2 nd frame member 22, and the thin plate W can be held substantially at the center of the frame 20 by the holding device 10. As a result, if the optical axis of the machining head 4 (see fig. 1) is set to be located at the center of the housing W, the thin plate W can be held so that the focal point of the laser beam is located substantially at the center of the thin plate W (material). Therefore, laser processing can be easily performed with the center portion of the thin sheet W as the center.

Further, since the tension applying mechanism 60 is disposed at a position symmetrical to a virtual line (not shown) passing through the center in the width direction (vertical direction in fig. 2) of the frame 20, it is possible to apply a substantially uniform tension in the width direction of the thin sheet W by holding the thin sheet W at the center in the longitudinal direction (vertical direction in fig. 2) of the 1 st member 30 and the 2 nd member 40.

In a state where a constant tension is applied to the thin sheet W by the tension applying mechanism 60, the cross-sectional area of the thin sheet W is reduced and the stress is increased as the laser cutting processing is performed, so that the amount of elongation (elastic deformation) of the thin sheet W during the processing is increased. At this time, a difference occurs between the cutting data preset in the control device 13 (see fig. 1) and the elongation of the web W, and the processing accuracy is lowered. In contrast, since the holding device 10 includes the movement restricting mechanism 70, the extension of the sheet W during processing can be restricted. This prevents the elastic deformation of the sheet W from changing during machining, thereby preventing the machining accuracy from being degraded.

When a fixed tension is applied to the sheet W by the tension applying mechanism 60 to cause the sheet W to stretch during laser processing, a tensile force may be applied to the linear member 51. If the state in which the linear member 51 is pulled and extended continues to be long, there is a risk that the linear member 51 will stretch or deteriorate. In contrast, since the holding device 10 includes the movement restricting mechanism 70, the tensile force applied to the linear member 51 during the laser processing can be suppressed. As a result, the linear member 51 can be prevented from being stretched or deteriorated.

Next, embodiment 2 will be described with reference to fig. 3. In embodiment 1, the holding device 10 in which the 1 st member 30 and the 2 nd member 40 can move in conjunction with each other via the linear member 51 is described. In contrast, in embodiment 2, the holding device 110 in which the 1 st member 130 and the 2 nd member 140 can move independently will be described. In addition, instead of the holding device 10 in embodiment 1, a holding device 110 is provided in the laser processing machine 1. In embodiment 2, the same portions as those in embodiment 1 are denoted by the same reference numerals, and the following description is omitted. Fig. 3 is a plan view of the holding device 110 for a thin sheet W according to embodiment 2.

The 1 st member 130 and the 2 nd member 140 of the holding device 110 include support members 131 and 141 arranged in parallel with the 1 st frame member 21 and the 2 nd frame member 22, respectively. The support members 131 and 141 are stretched between the 3 rd frame members 23 along the inner side of the 1 st frame member 21, and are fastened and fixed to the 3 rd frame members 23 by fastening bolts 131 a. Fastening holes (not shown) are formed at predetermined intervals in the 3 rd frame member 23 along the longitudinal direction (the left-right direction in fig. 3), and the support members 131 are fixed at positions corresponding to the size of the thin plate W. The support member 141 is provided along the inside of the 2 nd frame member 22, and both longitudinal end portions (end portions in the vertical direction in fig. 3) thereof are slidably held on guide surfaces (not shown) of the guide 24 in the front-rear left-right direction (end portions in the vertical direction in fig. 3).

The 1 st member 130 and the 2 nd member 140 include: elongated plate-like receiving members 132 and 142 (see fig. 4) arranged along the edge portions of the upper surfaces of the support members 131 and 141; pressing members 133, 143 disposed above the receiving members 132, 142; and fasteners 134 and 144 for applying a pressing force to the pressing members 133 and 143. Four fasteners 134 and 144 are disposed on the support members 131 and 141, respectively, at positions symmetrical with respect to a virtual line (not shown) passing through the center in the width direction (vertical direction in fig. 3) of the housing 20.

The side surface of the support member 141 on the 2 nd frame member 22 side is coupled to the cylinder 160 attached to the 2 nd frame member 22 via the link L. The support member 141 and the 2 nd frame member 22 are coupled by the coupling member 170. Further, one cylinder 160 is disposed at a position near the 3 rd frame member 23 and at a position symmetrical to a virtual line (not shown) passing through the center in the width direction (vertical direction in fig. 3) of the frame body 20. One coupling member 170 is disposed at each of positions located inward of the cylinder 160 in the width direction of the frame 20 and positions symmetrical with respect to the virtual line.

Next, the detailed structure of the vicinity of the support member 141 will be described with reference to fig. 4. Fig. 4 is a partially enlarged top view of the holding fixture 110. As shown in fig. 4, the cylinder 160 is attached to the 2 nd frame member 22 with the rod 161 facing the support member 141, and one end side of the link L is pin-connected to the tip end of the rod 161 so as to be swingable. On the other hand, a support member 162 fastened and fixed to a side surface of the support member 141 is pin-coupled to the other end side of the link L so as to be swingable.

Thus, when the cylinder 160 is operated to retract the drive rod 161, the support member 141 is pulled toward the cylinder 160 (rightward in fig. 4) via the link L by the retraction force, and tension is applied to the thin sheet W. This allows the thin sheet W to be held in a tensioned state in the frame 20 (see fig. 3). At this time, both longitudinal end portions of the support member 141 are slidably held on the guide surfaces of the guide 24 in the front-rear right-left direction, and the support member 141 is coupled to the cylinder 160 via two links L (see fig. 3), so that even if the thin plate W is fixed in a slightly loosened state, the support member 141 is pulled toward the 2 nd frame member 22 by the links L tilting in the horizontal direction. This allows the thin sheet W to be uniformly tensioned.

The cylinder 160 is a pneumatic cylinder that extends and contracts the drive rod 161 by air pressure, and is configured as a reciprocating cylinder that is operated in both directions by the air pressure to extend and contract the rod 161. Thus, by releasing the driving pressure of the cylinder 160 (atmospheric release), the driving force applied from the cylinder 160 to the support member 141 can be released.

The coupling member 170 is a member that couples the support member 141 and the 2 nd frame member 22, and is slidable between the bottom surface of the stopper member 171 and the upper surface of the base member 172, and a flat plate-shaped base member 172 that is in contact with the bottom surface of the flat plate-shaped stopper member 171 that is fastened and fixed to the side surface of the support member 141 by fastening bolts (not shown) and that protrudes toward the 2 nd frame member 22.

The stopper member 171 and the base member 172 are formed as flat surfaces having upper and lower surfaces parallel to each other, and these upper and lower surfaces are disposed parallel to the extending and contracting direction of the cylinder 160. Accordingly, when the support member 141 moves in parallel with the expansion and contraction of the cylinder 160, the bottom surface of the stopper member 171 and the upper surface of the base member 172 can slide.

A long hole 171a that is oblong in plan view and extends parallel to the extending and contracting direction of the rod 161 in the cylinder 160 is formed through the stopper member 171 in the plate thickness direction, and a shaft insertion hole (not shown) that is circular in plan view is formed through the base member 172 at a position corresponding to the long hole 171a of the stopper member 171 in the plate thickness direction. Further, a through hole (not shown) having a circular shape in plan view is formed in the 2 nd frame member 22 so as to penetrate therethrough in the plate thickness direction at a position corresponding to the shaft insertion hole of the base member 172. The handle portion 173 is screwed to the upper portion of the fastening shaft member 174, and the fastening shaft member 174 is inserted through the elongated hole 171a and the through hole (in the vertical direction of the plane of the drawing in fig. 4), and a fastening nut portion (not shown) having a double nut function is screwed to the lower end thereof so as to be unrotatable.

Thus, by rotating the handle 173, the handle 173 can be rotated with respect to the fastening shaft member 174, and the stopper member 171 and the base member 172 can be held between the nut portion (2 nd frame member 22) and the handle 173 (this state will be referred to as a "fastening state" hereinafter), and the support member 141 and the 2 nd frame member 22 can be fastened by the coupling member 170. That is, when the sheet W is cut, the support member 141 is pulled toward the 2 nd frame member 22 by the contraction force of the cylinder 160, and after the sheet W is in a tensioned state by the application of tension, the connection member 170 is brought into a fastened state by the operation of the handle portion 173, and the support member 141 and the 2 nd frame member 22 are connected by the connection member 170. As a result, the amount of extension of the sheet W during the cutting process of the sheet W can be limited.

The explanation will be made with reference to fig. 3. A distance detection device 180 for detecting the distance between the machining table 12 and the 1 st member 130 is disposed on the machining table 12. The distance detection device 180 is a device for detecting the distance to the 1 st member 130 and outputting the detection result to the control device 13 (see fig. 1), and includes a distance sensor (not shown) and an output circuit (not shown) for processing the detection result of the distance sensor and outputting the processed detection result to the control device 13. The distance sensor is the following sensor: the 1 st member 130 is irradiated with light from an internal light source (LED or laser diode), and the distance is detected by receiving the light reflected by the 1 st member 130 with an internal light receiving element (not shown).

The support rods 181 are disposed inside the housing 20 substantially in parallel with the 1 st member 130 and the 2 nd member 140 at a distance from each other. The support rod 181 supports the thin sheet W held by the 1 st member 130 and the 2 nd member 140, and an upper end of the support rod 181 abuts against a lower surface of the thin sheet W to support the thin sheet W at a predetermined height position. Sliding members 182 are attached to both ends of the support rod 181. The slide member 182 engages with the inner surface of the 3 rd frame member 23, and the support rod 181 can move along the 3 rd frame member 23. The slide members 182 are connected to each other by elastic members (springs) 183, and the elastic members (springs) 184 are connected between the 1 st frame member 21 and the 2 nd frame member 22 and the slide members 182, respectively.

Further, a cutout portion 181a for allowing light emitted from the distance detection device 180 to the 1 st member 130 to pass therethrough is cut out and formed at a predetermined portion of the support rod 181 positioned between the machining table 12 and the 1 st member 130. By forming the cutout portion 181a in the support rod 181, the distance detection from the 1 st member 130 by the distance detection device 180 and the support of the thin sheet W by the support rod 181 can be simultaneously realized.

When the 1 st member 130 and the 2 nd member 140 hold the sheet W, the lower surface of the sheet W is supported by the two support bars 181 and the processing table 12. Accordingly, the deflection of the sheet W due to its own weight, which is generated between the 1 st and 2 nd members 130 and 140 and the processing table 12, can be further reduced by the support rod 181, and the sheet W can be attached to the frame 20 substantially flat. As a result, even if the tension applied to the web W by the cylinder 160 is relatively small, the web W can be prevented from being deflected downward in the optical axis direction of the laser beam (toward the back side of the paper surface in fig. 3). If the tension applied to the thin plate W can be reduced, the amount of elastic deformation of the thin plate W held by tension can be reduced, and the pressure cylinder 160 having a small tension can be used.

Further, during the laser cutting process, the housing 20 moves together with the movement of the XY table 11 based on the cutting information from the control device 13 (see fig. 1). At this time, when the support rod 181 contacts the machining table 12, the support rod 181 moves via the slide member 182. When the housing 20 is moved in the opposite direction, the support rod 181 returns to the original position by the elastic members 183 and 184. Therefore, the support rod 181 does not hinder the laser processing.

In the present embodiment, the case where the elastic members 183, 184 are formed by springs has been described, but the present invention is not limited to this, and the elastic members 183, 184 may be formed of rubber or the like. Further, although the case where the slide members 182 are coupled to each other by the elastic member 183 has been described, the slide members 182 may be coupled to each other by a rigid body such as a link, and the 1 st frame member 21 and the 2 nd frame member 22 may be coupled to the slide members 182 by a compression spring. Further, by providing the damper, vibration of the support rod 181 caused by the elastic members 183 and 184 can be suppressed.

Next, the detailed structure of the holding device 110 will be described with reference to fig. 5 to 7. Fig. 5 is a cross-sectional view of the holding device 110 (item 2, 140) taken along line V-V of fig. 3. Here, the structure of the 2 nd member 140 will be described, and the 1 st member 130 having the same structure will not be described.

As shown in fig. 5, the 2 nd member 140 includes: a receiving member 142 having a mounting surface 142a on the inner side (left side in fig. 5) on which the thin sheet W is mounted; a wall portion 142b erected on the rear end side (right side in fig. 5) of the mounting surface 142a of the receiving member 142; an urging member 145 having one end fixed to an upper step portion 142c which is continuous with the upper end of the wall portion 142b and is formed in a stepped shape with the mounting surface 142 a; and a pressing member 143 that is fixed (abutted) to the other end side of the biasing member 145, is biased upward, and faces the mounting surface 142a at a predetermined interval along the longitudinal direction (the direction perpendicular to the sheet surface of fig. 5) of the mounting surface 142 a.

The receiving member 142 is fixed to the vicinity of an inner edge (left side in fig. 5) of the upper surface of the supporting member 141 by bolts or the like, and the mounting surface 142a is formed to be longer than the width (vertical direction in fig. 3) of the thin plate W in the longitudinal direction of the entire receiving member 142. The mounting surface 142a is formed with a groove portion 142a1 to form an uneven surface in the entire longitudinal direction. At the inner end of the loading surface 142a, a convex portion 142d formed in a protruding strip shape is provided to protrude upward in the entire length direction.

The wall portion 142b is provided upright on the rear end side (right side in fig. 5) of the mounting surface 142a in the entire longitudinal direction (vertical direction to the paper surface in fig. 5) of the receiving member 142, and is formed such that the upper portion protrudes inward (left side in fig. 5) from the lower portion (lower side in fig. 5). Since the wall portion 142b protrudes from the lower portion, when the thin sheet W is inserted between the mounting surface 142a and the pressing surface 143a of the pressing member 143, the distal end of the inserted thin sheet W can be prevented from passing over the wall portion 142 b. When the sheet W passes over the wall portion 142b, the distal end of the sheet W bends at the wall portion 142b and the upper step portion 142c when the pressing member 143 is pressed against the receiving member 142. In laser processing of the sheet W, the sheet W may be cut by irradiating one surface of the sheet W with a laser beam, reversed, and laser-engraved with characters or the like on the opposite surface.

The upper step portion 142c is a portion that is continuous with the upper end of the wall portion 142b and is formed in a stepped shape with the mounting surface 142a, and through holes 142e are formed to penetrate from the upper surface of the upper step portion 142c to the bottom surface of the receiving member 142 at two locations near both ends (in the vertical direction in fig. 3) of the receiving member 142. The urging member 145 is formed of a compression coil spring, and is inserted into the through hole 142e from one end side to be compressed between the upper surface of the support member 141 and the lower surface of the pressing member 143. Since the biasing member 145 is accommodated in the upper step portion 142c formed in a stepped shape with the mounting surface 142a by the wall portion 142b, when the thin plate W is inserted between the receiving member 142 and the pressing member 143, the thin plate W is blocked by the wall portion 142b and does not reach the biasing member 145. This prevents the biasing member 145 from touching and damaging the end of the thin sheet W.

The pressing member 143 has a groove 143b formed along the entire length thereof to receive the upper step portion 142c of the receiving member 142. A recess 143b is formed in the pressing member 143, and the upper step portion 142c of the receiving member 142 is received therein. Therefore, the pressing member 143 can be prevented from being displaced in the width direction (the left-right direction in fig. 5) with respect to the receiving member 142. The other end of the biasing member 145 abuts against the bottom surface of the concave groove 143b, and the biasing member 145 is compressed between the supporting member 141 and the pressing member 143, so that the pressing member 143 is biased upward. In this way, since the pressing member 143 is biased upward by the biasing member 145, a gap can be provided between the mounting surface 142a and the pressing surface 143a in advance. When the holding device 110 holds the thin plate W, the thin plate W is first inserted into the gap, and thus the operation can be easily performed.

A pressing surface 143a is formed on the inner side (left side in fig. 5) of the concave groove 143b in the entire longitudinal direction. The pressing surface 143a is a portion pressed by the mounting surface 142a of the receiving member 142, and a groove portion 143a1 is formed to be an uneven surface in the entire longitudinal direction. Since the groove portions 143a1, 142a1 are formed in the pressing surface 143a and the mounting surface 142a, frictional resistance between these surfaces and the sheet W can be increased when the sheet W is sandwiched. As a result, when the sheet W is stretched by the contraction driving cylinder 160 (see fig. 3 and 4), the stretched sheet W is prevented from slipping between the pressing surface 143a and the mounting surface 142 a.

The length of the pressing surface 143a in the longitudinal direction is formed longer than the width of the thin plate W in the direction perpendicular to the relative movement direction (the left-right direction in fig. 3) of the support member 141 (see fig. 3 and 4). This allows the sheet W to be sandwiched between the pressing surface 143a of the pressing member 143 and the mounting surface 142a of the receiving member 142 without warping. As a result, the elastic deformation amount of the thin plate W can be prevented from being varied in the entire longitudinal direction of the receiving member 142, and the processing accuracy can be improved.

The width-directional length of the pressing surface 143a is formed smaller than the width-directional length of the mounting surface 142 a. Thus, when the pressing surface 143a of the pressing member 143 is pressed against the thin sheet W after the thin sheet W is placed on the mounting surface 142a of the receiving member 142, the thin sheet W contacts the convex portion 142d provided to protrude inward of the mounting surface 142a, and is inclined from the convex portion 142d to the pressing surface 143a, as shown in fig. 5. Thus, when the pressure cylinder 160 (see fig. 3 and 4) is driven to tension the thin sheet W, a component of the tension force acts on the pressing surface 143a and the loading surface 142 a. As a result, the frictional resistance can be further increased, and therefore, the stretched sheet W can be prevented from slipping and coming off between the pressing surface 143a and the mounting surface 142 a.

The restricting portions 146 are members for restricting the upward movement amount of the pressing member 143 urged upward, and are disposed at two positions near both ends (in the vertical direction in fig. 3) of the pressing member 143. In the present embodiment, the regulating portion 146 is formed by a bolt including a shaft portion 146a and a head portion 146b, the shaft portion 146a is inserted into a through hole formed in the thickness direction (vertical direction in fig. 5) of the pressing member 143, and the lower end portion of the shaft portion 146a is screwed to the receiving member 142. The outer diameter of the head portion 146b is set larger than the inner diameter of the through hole of the pressing member 143 through which the shaft portion 146a is inserted, and the height from the upper surface of the support member 141 to the lower surface of the head portion 146b is set to the height against which the upper surface of the pressing member 143 to be biased abuts. As a result, the upper surface of the pressing member 143 abuts against the lower surface of the head portion 146b, and the further upward movement of the biased pressing member 143 is restricted.

Next, the fastening member of the 2 nd member 140 is explained with reference to fig. 6. Fig. 6 (a) is a cross-sectional view of the holding device 110 (No. 2 member 140) along line VI-VI of fig. 4, and fig. 6 (b) is a partially enlarged cross-sectional view of the receiving member 142 and the pressing member 143. In fig. 6 (a), the support member 162 visible on the right side of the support member 141 and a part of the handle 144e in the longitudinal direction are not shown.

As shown in fig. 6a, the 2 nd member 140 includes a fastening member 144 fixed by a bolt or the like near an outer edge (right side in fig. 6 a) of the upper surface of the support member 141. In the fastener 144, a pressing body 144a that presses an upper portion of a pressing surface 143a formed on the pressing member 143 is attached to a link 144b, and the link 144b is coupled to a bracket 144c fixed to an upper surface of the support member 141 by a pin 144 d. The handle 144e is coupled to the link 144b via a pin 144f, and is coupled to the bracket 144c via a link 144g via a pin 144 h.

Since the fastening tool 144 is configured as described above, when the handle 144e is pressed down, the pressing member 144a presses the pressing member 143, and the sheet W inserted between the loading surface 142a and the pressing surface 143a is sandwiched, as shown in fig. 6 (a). When the handle 144e is lifted upward, the link 144b rotates clockwise in fig. 6 (a) and the pressing body 144a moves upward, so that the pressing member 143 is lifted by the biasing force of the biasing member 145 (see fig. 5), and a gap is formed between the mounting surface 142a and the pressing surface 143 a. As a result, the sheet W can be inserted between the mounting surface 142a and the pressing surface 143a so as to be sandwiched therebetween.

Here, in order to clamp the sheet W between the receiving member 142 and the pressing member 143, first, the sheet W is inserted between the mounting surface 142a and the pressing surface 143a in a state before the 2 nd member 140 is relatively moved in a direction away from the 1 st member 130 (see fig. 3) (in a state where the cylinder 160 is extended and the distance between the 2 nd member 140 and the 1 st member 130 is made close to each other). At this time, a distance D (see fig. 6 b) between a lower end portion of a wall portion (not shown) of the receiving member 132 erected on the 1 st member 130 and a lower end portion of a wall portion 142b of the receiving member 142 erected on the 2 nd member 140 is set to be larger than a maximum value of a dimensional (length) tolerance of the thin plate W. Therefore, even if the size of the sheet W varies to the maximum value side within the tolerance (about ± 3 mm), the end portion of the sheet W inserted between the receiving member 142 and the pressing member 143 can be prevented from abutting against the wall portion 142 b.

Thus, the sheet W can be sandwiched between the 1 st member 130 and the 2 nd member 140 without slack, and sufficient tension can be stably applied to the sheet W by tensioning the sheet W. This prevents the amount of elastic deformation from varying with each sheet W due to the tension applied to the sheet W. This can improve the processing accuracy by the laser beam.

Next, the beam irradiation unit 180 will be described with reference to fig. 7 (a). Fig. 7 (a) is a cross-sectional view of the holding device 110 (item 2 140) taken along line VIIa-VIIa of fig. 4. As shown in fig. 7 (a), the 2 nd member 140 has through holes 140a and 140b formed therein so as to communicate vertically through the receiving member 142 and the pressing member 143 at a portion where the mounting surface 142a of the receiving member 142 and the pressing surface 143a of the pressing member 143 are vertically overlapped.

The through holes 140a and 140b are formed at positions on the boundary line between the receiving member 142 and the pressing member 143 on the side (left side in fig. 7) away from the wall portion 142 b. The nip boundary line is a line indicating a boundary at which the thin sheet W can be nipped between the loading surface 142a and the pressing surface 143a even when the thin sheet W is tensioned, if the end portion of the inserted thin sheet W exceeds the nip boundary line and is on the wall portion 142b side. In contrast, if the end of the inserted sheet W does not exceed the nip boundary, that is, if the area of the sheet W sandwiched between the loading surface 142a and the pressing surface 143a is narrowed, there is a possibility that the sheet W may be separated from between the loading surface 142a and the pressing surface 143a when the sheet W is tensioned.

In the present embodiment, the through hole 140a formed in the receiving member 142a houses a light beam irradiation portion 180 that irradiates a light beam toward the other through hole 140b, and the through hole 140b formed in the pressing member 143 houses a light receiving portion 181 that receives the light beam incident on the through hole 140 b. The light receiving unit 181 inputs the presence or absence of light beam detection to an output circuit (not shown) via the cable C, and the output circuit processes the detection result and outputs the result to the control device 13 (see fig. 1). When the light receiving unit 181 detects the light beam, the control device 13 determines that the area of the sheet W sandwiched between the mounting surface 142a and the pressing surface 143a is narrow, and may cause the sheet W to be separated from between the mounting surface 142a and the pressing surface 143a when the sheet W is tensioned. In order to prevent this problem, a warning sound or the like is given to the operator, and the operation of the laser beam machine 1 is put on standby.

On the other hand, when the light beam is not detected by the light receiving unit 181, it is determined that the inserted thin plate W exceeds the nip boundary line (the position of the through holes 140a and 140 b), and therefore the pressure cylinder 160 (see fig. 3) is driven to tension the thin plate W, and the laser processing is continued. When the size of the sheet W is short, the clamping and tensioning of the sheet W by the mounting surface 142a of the receiving member 142 and the pressing surface 143a of the pressing member 143 may become insufficient, which may cause a failure in detachment of the sheet W or a reduction in machining accuracy. However, since the laser processing machine 1 includes the beam irradiation unit 180, it is possible to determine whether or not the size of the sheet W is short before the laser processing, and thus it is possible to prevent a defect and a reduction in processing accuracy caused by processing without noticing the short size of the sheet W.

Next, the shapes of the pressing member 143 and the receiving member 142 will be described with reference to fig. 7 (b). Fig. 7 (b) is a cross-sectional view of the pressing member 143 and the receiving member 142 when the fastening member 144 (see fig. 6 (a)) is released. As shown in fig. 7b, the pressing surface 143a of the pressing member 143 is inclined in a direction away from the wall portion 142b and toward the mounting surface 142a of the receiving member 142 in the relative movement direction (the left-right direction in fig. 3) of the 2 nd member 140.

Thus, when the pressing member 143 is lowered by the fastening member 144 (see fig. 6 a) after the sheet W is loaded on the loading surface 142a, the inner side (left side in fig. 7 b) of the pressing surface 143b first comes into contact with the sheet W, and the contact area between the pressing surface 143a and the sheet W gradually increases as the pressing member 143 is lowered. Therefore, the sheet W is strongly pressed on the inner side of the pressing surface 143a than on the outer side (the right side in fig. 7 (b)). When the cylinder 160 (see fig. 3) is contracted to separate the 2 nd member 140 and the 1 st member 130, the force with which the inner edge of the pressing surface 143a is depressed into the sheet W acts to press the sheet W. As a result, the stretched sheet W can be prevented from sliding between the receiving member 142 and the pressing member 143, and a stretching force can be applied to the sheet W without loss, and the sheet W can be elastically deformed in a controlled state. As a result, the machining accuracy can be improved.

In embodiment 2, the light receiving unit 181 is housed in the through hole 140b formed in the pressing member 143, and the control device 13 operates the laser processing machine 1 in accordance with the presence or absence of incident light from the beam irradiation unit 180 disposed on the receiving member 142, but the present invention is not limited to this, and it is needless to say that the beam irradiation unit 180 may be disposed on the pressing member 143 and the light receiving unit 181 may be disposed on the receiving member 142.

The light receiving unit 181 is not necessarily required, and the light receiving unit 181 may not be accommodated in the through hole 140b formed in the pressing member 143. At this time, the presence or absence of the sheet W can be determined by visually checking the light beam passing through the through hole 140b by a person operating the laser processing machine 1. When the operator can visually confirm the light flux passing through the through hole 140b (when the size of the sheet W is short) despite the operation of holding the sheet W, the operator can prevent the occurrence of a defect by stopping the operation of the laser beam machine 1.

The holding device 110 has been described in the case where the support member 141 moves in a plane with respect to the support member 131, that is, in the case where the 2 nd member 140 moves in a plane with respect to the fixed 1 st member 130 to apply tension to the sheet W, but the present invention is not limited to this, and both the 1 st member 130 and the 2 nd member 140 may move to apply tension to the held sheet W. The same effect is obtained in this case.

Further, the case where the pressing surface 143a of the pressing member 143 is inclined inward (leftward in fig. 7 (b)) has been described, but the present invention is not limited thereto, and the mounting surface 142a of the receiving member 142 may be inclined inward. In this case, the thin sheet W may be strongly held by pressing the inner sides (the processing head 4 side) of the loading surface 142a and the pressing surface 143 a.

Further, although the case where the biasing member 145 is formed of a compression coil spring has been described, the present invention is not limited thereto, and other biasing members may be used. Examples of the other biasing member include a leaf spring, a coil spring, and an elastic body made of synthetic resin or rubber.

Next, embodiment 3 will be described with reference to fig. 8. In embodiment 2, the case where the 2 nd member 140 is pulled toward the 2 nd frame member 22 via the cylinder 160 for the link L to apply tension to the thin plate W and elastically deform the thin plate W uniformly is described. In embodiment 3, a case will be described in which the horizontal member 238 is provided in parallel with the support member 231 of the 1 st member 230 in order to elastically deform the thin sheet W more uniformly. Note that the same portions as those in embodiment 2 are denoted by the same reference numerals, and the following description is omitted. Fig. 8 is a plan view of a holding device 210 for a web W in embodiment 3.

The holding device 210 mainly includes: a support member 231, a lateral member 238 (the 1 st member 230), and a 2 nd member 240 disposed in parallel with the 1 st frame member 21; and fasteners 134 and 144 disposed on the upper surfaces of the support members 231 and 141, respectively, for holding the sheet W by sandwiching both ends of the sheet W therebetween.

The support member 231 is disposed along the inside of the 1 st frame member 21, and has a moving member 237 fastened and fixed to both ends thereof by fastening bolts (not shown), and is bridged between the 3 rd frame members 23 via the moving member 237. The moving member 237 is disposed on the upper surface of the 3 rd frame member 23, and is configured to be movable along a guide groove (not shown) formed in the longitudinal direction (the left-right direction in fig. 8) of the 3 rd frame member 23, and to be fastened and fixed at an arbitrary position of the 3 rd frame member 23 by a rotating handle 237 a.

The support member 231 has through holes 231a formed at two positions symmetrical to a virtual line (not shown) passing through the center in the longitudinal direction (vertical direction in fig. 8) of the 1 st frame member 21 and the 2 nd frame member 22, and extending from the side surface of the support member 231 on the 2 nd frame member 22 side (right side in fig. 8) to the side surface of the 1 st frame member 21 side (left side in fig. 8).

The lateral member 238 is bridged between the 3 rd frame members 23 along the support member 231, and both ends are fastened and fixed to the side surface of the 1 st frame member 21 side (left side in fig. 8) of the moving member 237 by fastening bolts 240. The lateral member 238 has a through hole 238c formed therethrough to communicate with the through hole 231a formed through the support member 231, from the side surface of the lateral member 238 on the support member 231 side (right side in fig. 8) to the side surface of the 1 st frame member 21 side (left side in fig. 8). The support member 231 and the lateral member 238 are fastened and fixed by a fastening member 239 inserted through the through holes 231a and 238 c.

The fastening member 239 is disposed at the following positions: two straight lines C (imaginary lines) connecting the fastening position (a shown in fig. 8) of the support member 231 of the fastening member 239 and the connection position (B shown in fig. 8) of the support member 141 of the cylinder 160 (the support member 162 (see fig. 4)) are parallel to each other.

Thus, when the cylinder 160 (see fig. 4) is operated to contract the drive rod 161, the support member 141 is pulled toward the 2 nd frame member 22 (right side in fig. 4) via the link L by the contraction force, and tension is applied to the thin sheet W. Since the support member 141 is connected to the cylinder 160 via the two links L, even if the thin plate W is fixed in a slightly loosened state, the support member 141 is slid by the guides 24 at both ends and tilted in the horizontal direction, and the thin plate W can be tensioned substantially uniformly.

Here, in the case where the support member 231 is fixed at both ends to the 3 rd frame member 23 via the moving member 237 (the case where the cross member 238 is not provided), when the cylinder 160 is driven to contract and the 2 nd member 240 is moved to apply tension to the thin plate W, tension acts on the thin plate W in the direction of inclination connecting the end of the support member 231 (the moving member 237) and the cylinder 160. Thereby, particularly, the vicinity of the edge of the thin plate W along the 3 rd frame member 23 is elastically deformed in a twisted manner. The laser processing is performed in a state where tension is applied to the thin plate W, and the tension is released after the laser processing, so that the thin plate W is returned to a state before the tension. When the thin plate W is uniformly and elastically deformed at a predetermined deformation ratio by applying tension, the thin plate W after being released from tension and elastically restored can be processed to a target dimension by performing laser processing based on a corrected dimension obtained by multiplying the target dimension by the deformation ratio.

On the other hand, since a tensile force acts on the web W in the oblique direction connecting the end of the support member 231 (the moving member 237) and the cylinder 160, the vicinity of the edge portion of the web W is elastically deformed in a twisted manner, and therefore the deformation rate in the vicinity of the edge portion becomes irregular, and it is difficult to calculate an accurate correction dimension. As a result, the thin sheet W cannot be processed to a target size, and the processing accuracy of the thin sheet W, particularly the processing accuracy in the vicinity of the edge portion, may be reduced.

However, in the holding device 210, the lateral member 238 provided in parallel with the support member 231 (the 1 st member 230) is fixed at both ends to the 3 rd frame member 23 via the moving member 237, and is fastened to the support member 231 by the fastening member 239. Therefore, when the pressure cylinder 160 is driven to contract and move the 2 nd member 240, tension can be applied to the web W held by the 1 st member 230 and the 2 nd member 240 from both side (left and right side in fig. 8) edge portions. This can prevent the sheet W from being elastically deformed by twisting. As a result, the deformation ratio of the sheet W can be accurately obtained for the entire sheet W, and the accurate corrected dimension can be calculated. This enables laser processing of the sheet W to a target size, thereby improving the processing accuracy of the sheet W.

Further, since the two straight lines C (imaginary lines) disposed to connect the fastening position (a shown in fig. 8) of the support member 231 of the fastening member 239 and the coupling position (B shown in fig. 8) of the support member 141 of the cylinder 160 (the support member 162 (see fig. 4)) are parallel to each other, when the drive cylinder 160 is contracted to apply tension to the thin sheet W, a force is applied to the thin sheet W in the parallel direction connecting the fastening member 239 and the cylinder 160. As a result, the processing accuracy of the sheet W can be further improved as compared with the case where the fastening position a and the coupling position B are not parallel.

Further, since the lateral member 238 is provided in parallel on the 1 st member 230 on the side (the 1 st frame member 21 side) of the 1 st member 230 away from the 2 nd member 240 in the plane where the 1 st member 230 and the 2 nd member 240 are located, the rigidity of the 1 st member 230 can be increased in the direction of the force acting when the sheet W is stretched, as compared with the case where the lateral member 238 is provided in parallel on the bottom surface side (the back side of the paper surface in fig. 8) of the 1 st member 230. This also suppresses deformation of the 1 st member 230, and therefore, tension can be uniformly applied to the thin sheet W, and the processing accuracy can be further improved.

Next, the detailed structure of the cross member 238 will be described with reference to fig. 9. Fig. 9 is a cross-sectional view of the holding device 210 (part 1 230) taken along line IX-IX of fig. 8. As shown in fig. 9, the horizontal member 238 is formed of an angle steel having a substantially L-shaped cross section and including a web 238a and a flange 238 b. The web 238a is located on the side surface of the support member 231 on the 1 st frame member 21 (see fig. 8) side, and the flange 238b is located on the bottom surface of the support member 231. A through hole 238c is formed in the web 238a, and a fastening member 239 is inserted and fastened to the support member 231. Since the lateral member 238 has the web 238a and the flange 238b, the cross-sectional secondary torque of the lateral member 238 can be increased, the flexural rigidity can be improved, and the weight of the lateral member 238 can be reduced.

Namely, the following directions are arranged: since the plane of web 238a is perpendicular to the expansion and contraction direction (the left-right direction in fig. 9) of pressure cylinder 160 (see fig. 8) and the plane of flange 238b is parallel to it, the bending rigidity of cross member 238 can be improved. Accordingly, the 1 st member 230 to which the lateral member 238 is fastened and fixed, and thus the weight of the holding device 210 can be reduced, so that the moving device (not shown) of the XY stage 11 (see fig. 1) that moves in a plane can be downsized, the energy required for driving the moving device can be suppressed, and the energy efficiency can be improved. Further, since the lateral member 238 is disposed such that the flange 238b is positioned on the bottom surface of the support member 231, the lateral member 238 can be made to follow the side surface and the bottom surface of the support member 231, and the space occupied by the lateral member 238 and the support member 231 can be reduced.

The fastening member 239 fastens the support member 231 between the web 238a and the flange 238b, without fastening the support member 231 between the flange 238b and the fastening member 239, so that the axis of the fastening member 239 is arranged in the direction perpendicular to the longitudinal direction (the direction perpendicular to the sheet of fig. 9) of the support member 231. As a result, the direction of the force (the left-right direction in fig. 9) acting when the web W is tensioned can be aligned with the direction of the axis of the fastening member 239. This prevents bending stress from acting on the fastening member 239, and increases the rigidity of the 1 st member 230. Therefore, the 1 st member 230 can be prevented from being deformed, the tension can be uniformly applied to the thin plate W, and the processing accuracy can be improved.

Next, the moving member 237 to which the cross member 238 (see fig. 8) is fastened and fixed will be described with reference to fig. 10. Fig. 10 is a side view of a main part of the holding fixture 210 as viewed from the arrow X direction of fig. 8. In fig. 10, the longitudinal direction of the support member 231 and the lateral member 238 are not shown.

As shown in fig. 10, a hole 237c having a screw thread formed on the inner periphery thereof is bored in a side surface 237b of the 1 st frame member 21 (see fig. 8) of the moving member 237 disposed on the upper surface of the 3 rd frame member 23. Through holes corresponding to these holes 237c are formed in the lateral member 238 (see fig. 8), and the lateral member 238 is fixed to the moving member 237 by fastening with fastening bolts 240 (see fig. 8). Further, since the lateral member 238 has the flange 238b (see fig. 9) along the bottom surface of the support member 231, a recess for accommodating the flange 238b is provided on the side surface 237b of the moving member 237, or the flange 238b is partially removed from the moving member 237, so that the flange 238b does not hinder the fixing to the moving member 237.

The end portion on the front side (right side in fig. 10) of the moving member 237 is formed in a step shape having vertical surfaces 237d, 237f and horizontal surfaces 237e, 237 g. On the other hand, the end of the support member 231 is also formed in a step shape having vertical surfaces 231b and 231d and horizontal surfaces 231c and 231e corresponding to the shape of the end of the moving member 237. The horizontal surfaces 231c and 231e at the ends of the support member 231 come into contact with the horizontal surfaces 237e and 237g at the ends of the moving member 237, and both ends of the support member 231 are placed on the moving member 237. Since the support member 231 is fastened and fixed to the lateral member 238 by the fastening member 239 and both ends are placed on the moving member 237, it can be stably fixed to the lateral member 238 without rattling in the vertical direction (vertical direction in fig. 10).

Further, since the vertical surfaces 231b and 231d of the end portions of the support member 231 are not in close contact with the vertical surfaces 237d and 237f of the end portions of the moving member 237, and a gap is formed therebetween, the support member 231 can be prevented from being restricted by the moving member 237, and the force acting on the thin sheet W in the direction in which the end of the support member 231 (the moving member 237) and the cylinder 160 are connected to each other can be prevented when the drive cylinder 160 (see fig. 8) is contracted. This prevents the thin plate W from being elastically deformed by twisting in the vicinity of the edge along the 3 rd frame member 23.

The present invention has been described above based on the embodiments, but the present invention is not limited to the above embodiments, and it can be easily estimated that various modifications can be made without departing from the spirit of the present invention. For example, the numerical values (for example, the number of each component) exemplified in the above embodiment are merely examples, and it is needless to say that other numerical values may be adopted.

In embodiment 3, a case where two fastening members 239 are disposed on the support member 231 and two cylinders 160 are disposed at corresponding positions on the 2 nd member 240 has been described (a case where the number of fastening members 239 and cylinders 160 is the same), but the present invention is not limited to this and other embodiments are possible. Alternatively, for example, when two or more fastening members 239 are disposed, one cylinder 160 may be disposed at a position corresponding to a virtual line (not shown) passing through the center in the width direction (vertical direction in fig. 8) of the housing 20, or a plurality of cylinders 160 may be disposed symmetrically with respect to a virtual line passing through the center in the width direction of the housing 20, with the number of fastening members 239 and the number of cylinders 160 being different. In these cases, the support member 231 can be prevented from being restricted at both ends by the 3 rd frame member 23, and the thin plate W can be prevented from being distorted and deformed.

In embodiment 3, the case where the web 238a of the lateral member 238 is fixed to the side surface of the support member 231 and the flange 238b is disposed along the bottom surface of the support member 231 has been described, but the present invention is not limited to this, and the web 238a of the lateral member 238 may be fixed to the side surface of the support member 231 and the flange 238b may be extended toward the 1 st frame member 21 (left side in fig. 8). Thus, the bottom surface of the support member 231 does not need to be designed in consideration of the arrangement of the flange 238 b. As a result, the degree of freedom in designing the support member 231 can be increased, and the need for partially removing the flange 238b and the like due to the relationship with the moving member 237 is eliminated, and the attachment of the lateral member 238 is also facilitated.

In embodiment 3, the case where the horizontal member 238 is formed of angle steel having an L-shaped cross section has been described, but the present invention is not limited to this, and other horizontal members may be adopted. Examples of the other horizontal member include a solid square column-shaped or hollow square tube-shaped member, and various types of steel sections having a web and a flange, such as H-section steel, I-section steel, channel steel, and Z-section steel. Further, the present invention is not limited to the steel section, and it is needless to say that a member formed with flanges and webs by bending, welding, or the like using an iron plate, a steel plate, or the like may be used.

In embodiment 3, the case where the lateral member 238 is fixed to the 3 rd frame member 23 via the moving member 237 has been described, but the present invention is not limited to this, and it is needless to say that both ends of the lateral member 238 may be directly fixed to the 3 rd frame member 23 using fastening bolts or the like.

In embodiment 3, the case where the fastening member 239 is formed of a bolt and a nut has been described, but the present invention is not limited to this, and it is needless to say that other fastening members than a bolt and a nut such as a stopper member may be used.

In embodiment 3, the case where the end portions of the moving member 237 and the support member 231 include the vertical surfaces 237d, 237f, 231b, and 231d and the horizontal surfaces 237e, 237g, 231c, and 231e formed in the stepped shape has been described, but the present invention is not limited to this, and the vertical surfaces may be inclined with respect to the horizontal direction and the vertical direction. The same operation and effect as those of the above embodiment can be obtained as long as the support member 231 is not restricted by the moving member 237 with respect to the horizontal load.

In each of the above embodiments, the embodiment may be modified by adding a part or a plurality of parts of the structure of the other embodiments to the embodiment or by exchanging the part or the plurality of parts of the structure of the embodiment.

For example, it is needless to say that the pressure cylinder 160 described in embodiment 2 and embodiment 3 may be provided instead of the tension applying mechanism 60 described in embodiment 1, and the coupling member 170 described in embodiment 2 and embodiment 3 may be provided instead of the movement restricting mechanism 70. It is needless to say that the lateral member 238 and the like described in embodiment 3 may be arranged side by side with the 1 st member 30 described in embodiment 1 and fastened and fixed thereto.

Description of reference numerals:

1 … laser processing machine

4 … processing head

10. 110, 210 … holding device

11 … XY stage

21 … No. 1 frame material

22 … No. 2 frame material

23 … No. 3 frame material

30. 130, 230 … part 1

32. 42, 133, 143 … pressing member

33. 43, 134, 144 … fastener

40. 140 … part 2

50 … wheel

51 … Linear Member

60 … tension applying mechanism

160 … pressure cylinder (tension action mechanism)

70 … movement limiting mechanism

170 … connecting component (movement limiting mechanism)

142a … loading surface

142b … wall portion

142c … upper section

143a … pressing surface

145 … force application part

181 … supporting rod

238 … transverse component

239 … fastening member

L … connecting rod

O … optical axis

W … sheet.

Claims (9)

1. A thin plate holding device in a laser processing machine, the laser processing machine comprising: a processing head which irradiates a laser beam to a thin plate to be processed and injects an assist gas; and an XY stage moving in a plane in a direction perpendicular to an optical axis of the laser light irradiated from the processing head,

the disclosed device is characterized by being provided with:

a1 st frame member and a 2 nd frame member which are fixed to the XY stage and opposed to each other with a predetermined distance therebetween;

a1 st member disposed between the 1 st frame member and the 2 nd frame member and sandwiching one end of the thin plate;

a 2 nd member configured to be relatively movable in a direction away from the 1 st member, arranged between the 1 st frame member and the 2 nd frame member along the 2 nd frame member, and sandwiching the other end of the thin plate opposite to the one end;

a plurality of links, one end of which is connected to a plurality of portions of the 2 nd member and is formed to be capable of swinging in a plane intersecting the optical axis;

a tension applying mechanism coupled to the other ends of the links, for applying a force to the 2 nd frame member from the 2 nd member, and for applying a tension to the thin plate sandwiched between the 1 st member and the 2 nd member at both ends,

the 1 st member and the 2 nd member include: a loading surface on which the thin plate is loaded; wall parts respectively erected on the 1 st frame member side and the 2 nd frame member side of the loading surfaces,

the distance between the lower ends of the wall portions is set to be greater than the maximum value of the dimensional tolerance of the sheet in a state before the 2 nd member is relatively moved in a direction away from the 1 st member.

2. A thin plate holding device in a laser processing machine, the laser processing machine comprising: a processing head which irradiates a laser beam to a thin plate to be processed and injects an assist gas; and an XY stage moving in a plane in a direction perpendicular to an optical axis of the laser light irradiated from the processing head,

the disclosed device is characterized by being provided with:

a1 st frame member and a 2 nd frame member which are fixed to the XY stage and opposed to each other with a predetermined distance therebetween;

a1 st member disposed between the 1 st frame member and the 2 nd frame member and sandwiching one end of the thin plate;

a 2 nd member configured to be relatively movable in a direction away from the 1 st member, arranged between the 1 st frame member and the 2 nd frame member along the 2 nd frame member, and sandwiching the other end of the thin plate opposite to the one end;

a linear member having one end connected to the 2 nd member and the other end connected to the 1 st member;

a wheel around which the linear member is wound and which is rotatably supported by the 1 st member;

a tension applying mechanism for applying a force to the 2 nd frame member and applying a tension to the thin plate sandwiched between the 1 st member and the 2 nd member at both ends,

the 1 st member and the 2 nd member include: a loading surface on which the thin plate is loaded; wall parts respectively erected on the 1 st frame member side and the 2 nd frame member side of the loading surfaces,

the distance between the lower ends of the wall portions is set to be greater than the maximum value of the dimensional tolerance of the sheet in a state before the 2 nd member is relatively moved in a direction away from the 1 st member.

3. A thin plate holding device in a laser processing machine, the laser processing machine comprising: a processing head which irradiates a laser beam to a thin plate to be processed and injects an assist gas; and an XY stage moving in a plane in a direction perpendicular to an optical axis of the laser light irradiated from the processing head,

the disclosed device is characterized by being provided with:

a1 st frame member and a 2 nd frame member which are fixed to the XY stage and opposed to each other with a predetermined distance therebetween;

a1 st member disposed between the 1 st frame member and the 2 nd frame member and sandwiching one end of the thin plate;

a 2 nd member configured to be relatively movable in a direction away from the 1 st member, arranged between the 1 st frame member and the 2 nd frame member along the 2 nd frame member, and sandwiching the other end of the thin plate opposite to the one end;

a support rod disposed between the 2 nd member and the 1 st member, for supporting the lower surface of the thin plate sandwiched between the 1 st member and the 2 nd member at both ends;

a tension applying mechanism for applying a force to the 2 nd frame member from the 2 nd member and applying a tension to the thin plate sandwiched between the 1 st member and the 2 nd member at both ends,

the 1 st member and the 2 nd member include: a loading surface on which the thin plate is loaded; wall parts respectively erected on the 1 st frame member side and the 2 nd frame member side of the loading surfaces,

the distance between the lower ends of the wall portions is set to be greater than the maximum value of the dimensional tolerance of the sheet in a state before the 2 nd member is relatively moved in a direction away from the 1 st member.

4. The thin plate holding device according to any one of claims 1 to 3, comprising:

a 3 rd frame member, both ends of which are fixed to the 1 st frame member and the 2 nd frame member and are opposed to each other with a predetermined distance therebetween;

a horizontal member, both ends of which are fixed to the 3 rd frame member and which is arranged in parallel with the 1 st member;

and a fastening member for fastening the horizontal member and the 1 st member.

5. The sheet holding device as set forth in claim 4,

the fastening members and the tension applying mechanism are disposed at a plurality of positions on the 1 st member and the 2 nd member,

the fastening member and the tension applying mechanism are arranged at the following positions: a plurality of straight lines connecting the fastening position of the fastening member at the 1 st member and the connection position of the tension applying mechanism at the 2 nd member are parallel.

6. The thin plate holding device according to claim 5, comprising:

the transverse members are arranged side by side on a side of the 1 st member away from the 2 nd member in a plane in which the 1 st member and the 2 nd member are located, and the fastening member is disposed such that an axis thereof is along the straight line.

7. The thin plate holding device as claimed in any one of claims 1 to 3,

the 1 st member and the 2 nd member include:

a biasing member having one end disposed on an upper step portion which is connected to an upper end of the wall portion and is formed in a stepped shape with respect to the mounting surface,

a pressing member that is biased upward by the biasing member, faces the loading surface at a predetermined distance in a longitudinal direction of the loading surface, and has a pressing surface that is formed longer than a width of the thin plate in a direction perpendicular to a relative movement direction of the 2 nd member;

and a fastening member configured to lower the pressing member against the biasing force of the biasing member and press the pressing surface against the sheet mounted on the mounting surface.

8. The sheet holding device as set forth in claim 7,

the upper side of the wall portion protrudes in the direction of the processing head with respect to the lower side.

9. The thin plate holding device as claimed in any one of claims 1 to 3, further comprising a movement restricting mechanism for restricting relative movement of said 2 nd member with respect to said 1 st member against an urging force by said tension applying mechanism.