JP2010194602A - Protective sheet for workpiece to be laser-machined and workpiece to be laser-machined stuck with the same - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a protective sheet to be stuck on a workpiece to be laser-machined, which can improve operability for piercing and cutting on the workpiece by minimizing peeling-off of the protective sheet stuck on the workpiece, and to provide the workpiece to be laser-machined stuck with the protective sheet. <P>SOLUTION: The protective sheet 10 for the workpiece to be laser-machined is stuck on the workpiece 12 on which a required laser machining is applied by irradiating laser beam 34 while assist gas 40 is blown to a processing point 16 by a laser machining apparatus 20. A plurality of penetrated parts (through-hole 14 or cut line 18) which penetrate from the front side to the back side of the protective sheet 10 are prepared at a designated interval. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a protective sheet for laser-worked workpieces, and more particularly, a protective sheet to be applied to prevent scratches and dirt such as fingerprints on workpieces that are subjected to laser processing by irradiating laser light, and to which the protective sheet is applied. Further, the present invention relates to a laser processed workpiece.

  2. Description of the Related Art Conventionally, laser processing apparatuses that perform drilling or cutting of a workpiece with laser light are known. Unlike the conventional punching process such as press processing, the laser processing apparatus can perform drilling and cutting with high accuracy, and there is no burr on the part where the workpiece has been drilled or cut with laser light. The punching die has the advantage that it is unnecessary. This laser processing apparatus is suitable for high-precision processing although it is not suitable for mass production because it is necessary to perform drilling and cutting processing on each workpiece one by one.

  By the way, in a laser processing apparatus that drills or cuts a workpiece with a laser beam condensed by a condenser lens, the workpiece is melted around when drilling or cutting with a laser beam. In addition, the molten material is scattered to damage the workpiece, and there is a danger that the condenser lens is soiled by the scattered material. Therefore, the assist gas is jetted from the opening formed at the lower end of the laser processing head to the processed part of the workpiece, and the melted material melted by the laser light emitted from the laser processing head is prevented from scattering. (See Patent Document 1).

  That is, in such a laser processing apparatus, as shown in FIGS. 10 and 11, a high-pressure assist gas 140 is injected from the opening 130 at the lower end of the nozzle portion 128 of the laser processing head 124 to the processing portion 116 of the workpiece 112. However, the workpiece 112 is drilled or cut by the laser beam 134 collected by the condenser lens 132. When bending or cutting the workpiece 112 that has been punched or cut, the surface of the workpiece 112 is damaged by the bending apparatus. Therefore, in order to prevent the surface of the workpiece 112 from being damaged, a protective sheet 110 for preventing scratches is attached to the surface of the workpiece 112.

  Most of the protective sheet 110 attached to the surface of the workpiece 112 is often peeled off after being punched, cut or bent. If the protective sheet 110 is strongly bonded to the surface of the workpiece 112, it becomes difficult to peel off later, or an adhesive or the like remains on the surface of the workpiece 112 from which the protective sheet 110 has been peeled off. A protection sheet 110 that can be easily peeled off was attached to the workpiece 112. In this case, the adhesive strength of the protective sheet 110 is weak and often peels off due to the wind pressure generated by the high-pressure assist gas 140 ejected from the opening 130 of the laser processing head 124 and floats. In this case, as shown in FIG. 12, a part of the protective sheet 110 is peeled off from the workpiece 112, and is about 1.5 mm from a holed or cut part with a small dimension to about 7 mm from a holed or cut part with a large dimension. It floated in the range of 0.0 mm.

JP 2007-61861 A

  However, if the protective sheet that prevents the workpiece from being damaged is peeled off and lifted up with large dimensions from the punched or cut parts, the melt of the protective sheet will adhere to the tip of the laser processing head. As a result, the inside of the opening at the lower end of the nozzle portion serving as the assist gas outlet is deformed. As a result, the discharge direction of the assist gas injected from the opening is changed, resulting in poor cutting of the workpiece. In addition, when the nozzle portion of the laser processing head is caught on the protective sheet that has been lifted with a large size, there is a problem that workability deteriorates, such as a stop sensor working and sometimes the cutting processing operation stops.

  The present invention is made in order to solve the problems of the related art, and by minimizing the peeling off of the protective sheet affixed to the workpiece, it is possible to open holes in the workpiece. It is an object of the present invention to provide a protective sheet that can be satisfactorily cut and applied to a laser processed workpiece and a laser processed workpiece to which the protective sheet is attached.

  In order to solve the above-described problems, the protective sheet for a laser-machined workpiece according to the present invention is applied to a workpiece to be subjected to a required laser machining by irradiating a laser beam while spraying an assist gas on a machining portion by a laser machining apparatus. A plurality of penetrating portions penetrating the front and back surfaces are provided at predetermined intervals.

  Further, in the protective sheet for laser-worked workpieces according to claim 2, in the above, the through part is a through hole penetrating the front and back of the protective sheet, and the diameter of the through hole is 0.25 mm or more. It is 00 mm or less.

  According to a third aspect of the present invention, there is provided the protective sheet for laser-worked workpieces according to the second aspect, wherein the diameter of the through hole is 0.50 mm.

  According to a fourth aspect of the present invention, there is provided a protective sheet for a laser-machined workpiece according to the first aspect, wherein the penetrating portion is a cut that penetrates the front and back of the protective sheet.

  According to a fifth aspect of the present invention, there is provided the protective sheet for laser-machined workpieces according to any one of the first to fourth aspects, wherein the through portions are arranged at intervals of 1.00 mm or more and 5.00 mm or less. It is characterized by that.

  Further, the laser-machined workpiece according to claim 6 is characterized in that the protective sheet for laser-machined workpiece according to any one of claims 1 to 5 is attached to the surface.

  The present invention provides a protective sheet for a laser-machined workpiece as in claim 6, for example, when performing the required laser machining by irradiating a laser beam while spraying an assist gas on a machining portion of the laser-machined workpiece by a laser machining apparatus. If a laser-worked workpiece having a surface attached thereto is used, the assist gas that has entered between the laser-worked workpiece and the protective sheet can be released to the outside from a plurality of through portions provided in the protective sheet. As a result, for example, the protective sheet affixed to the laser processing workpiece is peeled off from the punched or cut portion with a large size due to the wind pressure of the high-pressure assist gas sprayed from the tip of the laser processing head, and is lifted. Such inconvenience can be prevented in advance. Accordingly, it is possible to prevent inconveniences such as the melt of the protective sheet adhering to the tip of the laser processing head and deforming the inside of the opening at the tip of the nozzle portion serving as the assist gas outlet. In addition, the discharge direction of the assist gas sprayed from the opening changes, resulting in poor cutting of the work piece, and the nozzle part of the laser processing head caught on the protective sheet that has been lifted with a large size, so that the stop sensor It is possible to prevent inconveniences such as the fact that the cutting operation is sometimes stopped by working.

  Further, the through portion is formed as a through hole as in claim 2, and the diameter of the through hole is formed to be 0.25 mm or more and 2.00 mm or less, and the interval between them is 1.00 mm or more and 5. If it is arranged at an interval of 00 mm or less, when the laser processing workpiece is drilled or cut with laser light, the protective sheet of the drilled or cut portion is larger than the distance between the penetration portions as in the prior art. It is possible to reliably prevent the inconvenience of peeling off and rising. In addition, even with the high pressure assist gas blown from the tip of the laser processing head, the protective sheet is not removed beyond the interval between the through portions, so after drilling or cutting the laser processed workpiece, Even when bending is performed, it is possible to prevent inconvenience that the surface of the laser processing workpiece is damaged by the bending apparatus, and it is possible to maintain a clean appearance. As a result, the laser processing accuracy can be improved and the appearance can be maintained in a clean state, so that the commercial value of the laser processed workpiece can be greatly improved. Therefore, the convenience of the protective sheet affixed to the laser processed workpiece and the laser processed workpiece affixed with the protective sheet can be greatly improved.

  In particular, when the penetrating portion is a cut that penetrates the front and back sides of the protective sheet as in the fourth aspect, the entire surface of the workpiece can be covered with no hole in the protective sheet. As a result, the surface of the laser-worked workpiece is damaged by the bending device even when the workpiece is handled before being processed, and when bending is performed after drilling or cutting the workpiece. Can be prevented, and a beautiful appearance can be maintained. As a result, the laser processing accuracy can be improved and the appearance can be maintained in a clean state, so that the commercial value of the laser processed workpiece can be greatly improved. Therefore, the convenience of the protective sheet affixed to the laser processed workpiece and the laser processed workpiece affixed with the protective sheet can be greatly improved.

BRIEF DESCRIPTION OF THE DRAWINGS It is a front view of the protection sheet for laser processing workpieces which shows one Example of this invention (Example 1). It is a side view of the protection sheet for laser processing workpieces which shows the state where the protection sheet for laser processing workpieces was stuck on the workpiece. It is the schematic of the laser processing apparatus which shows the state which perforates and cuts with a laser beam to the workpiece by which the protection sheet for laser processing workpieces was stuck. It is a figure which shows distribution | circulation of the assist gas when the drilling and the cutting process are performed to the workpiece by which the protection sheet for laser processing workpieces was stuck with the laser beam. It is an enlarged plan view of the workpiece which shows the peeling state of a protection sheet when a circular hole is opened with a laser beam. It is a top view of the to-be-processed object which shows the peeling state of a protection sheet when a circular hole is opened with the laser beam of the same FIG. It is a front view of the protection sheet for laser processing workpieces which shows one Example of this invention (Example 2). It is a front view of the other protection sheet for laser processing workpieces which shows one Example of this invention. It is a front view of the other protection sheet for laser processing workpieces which shows one Example of this invention. It is the schematic of the laser processing apparatus which shows the state by which the punching and cutting process are performed with the laser beam to the workpiece by which the conventional protection sheet for laser processing workpieces was stuck. It is a figure which shows the distribution | circulation of the conventional assist gas when the drilling and the cutting process are performed to the workpiece by which the protection sheet for laser processing workpieces was stuck with the laser beam. It is a top view of a to-be-processed object which shows the peeling state of a protection sheet when a circular hole is opened with the laser beam in the to-be-processed object with which the conventional protection sheet was stuck.

  In the present invention, when processing is performed by irradiating a laser beam while spraying an assist gas from a laser processing apparatus to a processing portion of a laser processing workpiece, the protective sheet attached to the surface of the laser processing workpiece is peeled off and floated The main feature is to prevent it. For the purpose of preventing the protective sheet affixed to the surface of the laser processed workpiece from being peeled off and lifted by the assist gas blown from the laser processing apparatus, only a plurality of holes for allowing the assist gas to escape are provided in the protective sheet. Realized with a simple structure.

  Next, embodiments of the present invention will be described in detail with reference to the drawings. FIG. 1 is a front view of a laser-machined workpiece protection sheet 10 showing an embodiment of the present invention, and FIG. 2 shows a laser-machined workpiece protection sheet 10 attached to a laser-machined workpiece 12. The side view of the protection sheet 10 for a laser processing workpiece is shown, respectively.

  The protective sheet 10 for a laser-machined workpiece in the present embodiment (hereinafter, the protective sheet 10 for a laser-machined workpiece is referred to as a protective sheet 10) is irradiated with a laser beam 34 irradiated from the laser machining apparatus 20. Drilling or cutting is performed on the processed portion 16 where the workpiece 12 (a metal plate such as a stainless steel plate, a steel plate, an aluminum plate, a copper plate, or the like) is drilled or cut, or on the laser processed workpiece 12. After that, when performing bending or the like, the surface of the workpiece 12 is affixed to prevent the laser processing workpiece 12 from being damaged by the bending apparatus.

  As shown in FIGS. 1 and 2, the protective sheet 10 is made of a low-density polyethylene film or a polyvinyl chloride film having a thickness of about 65 μm. The laser processing apparatus 20 will be described in detail later. Further, the laser processed workpiece 12 has a surface on which the protective sheet 10 is attached as a front surface and a surface on which the protective sheet 10 is not attached as a back surface.

  The protective sheet 10 is provided with a plurality of through holes 14 (shown in FIGS. 4 and 5) that penetrate through the front and back of the protective sheet 10, and the through holes 14 have a diameter of about 0. .25 mm or more and 2.00 mm or less, preferably 0.50 mm. These through-holes 14 are arranged at predetermined intervals throughout the protective sheet 10, and the interval A1 between the adjacent through-holes 14 in the Y-axis direction (vertical direction in FIG. 5) and the X-axis direction (in FIG. 5). The interval A2 in the left-right direction is 1.00 mm or more and 5.00 mm or less, preferably 1.00 mm (the interval between the edge of the adjacent through hole 14). In the embodiment, the through hole 14 is a circular hole.

  One surface of the protective sheet 10 is coated with an acrylic adhesive having a relatively weak adhesive force, so that the protective sheet 10 can be attached to the surface side of the laser processed workpiece 12 with this adhesive. It is configured. The protective sheet 10 is attached to the surface of the laser processed workpiece 12 (the left side surface in FIG. 2) with an applied adhesive, and can be drilled or cut with a laser beam 34. The workpiece 12 (hereinafter, the laser-machined workpiece 12 is referred to as the workpiece 12) is completed.

  Here, as shown in FIG. 3, the laser processing device 20 oscillates a laser oscillation device 22 that oscillates a laser beam 34 that can drill or cut the workpiece 12, and is oscillated from the laser oscillation device 22. A laser processing head 24 that blows the assist gas 40 onto the processing portion 16 of the workpiece 12 while irradiating the workpiece 12 with the laser beam 34, and an assist gas supply device that supplies the compressed assist gas 40 to the laser processing head 24. 38, a support table 42 that moves in the horizontal plane X-axis and Y-axis directions and supports and fixes the workpiece 12, and a control device 44 that controls these.

  The laser processing device 20 is provided with a control device 44 composed of a general-purpose microcomputer, and the laser processing device 20 is configured such that the operation is controlled by the control device 44. Note that a technique for irradiating the workpiece 12 with the laser beam 34 by the laser processing apparatus 20 to perform drilling or cutting on the workpiece 12 is a well-known technique and will be described in detail. Omitted. Further, since the technology for controlling the laser processing device 20 by the control device 44 is also a well-known technology, detailed description thereof will be omitted.

  The laser processing head 24 is provided continuously with a cylindrical housing portion 26 containing a condensing lens 32 capable of condensing a laser beam 34, and a lower portion of the housing portion 26 (lower portion in the figure). And a hollow inverted conical nozzle portion 28 having a space 29 therein. Specifically, the nozzle portion 28 is narrowed as it is separated from the lower portion of the housing portion 26, and includes a thin opening portion 30 having an open front end (lower end). Further, an introduction pipe 36 is connected to the assist gas supply device 38, and this introduction pipe 36 is connected to the nozzle portion 28. That is, the assist gas supply device 38 communicates with a space portion 29 formed in the nozzle portion 28 via the introduction pipe 36, and the space portion 29 is exposed to the outside outside through a narrow opening 30 at the lower end of the nozzle portion 28. Communicate.

  The support table 42 for supporting and fixing the workpiece 12 and the laser processing head 24 are configured to be relatively movable in a horizontal plane by a driving device (not shown), and the laser processing head 24 includes the laser oscillation device. 22 is connected. The laser processing head 24 is provided with a lifting device (not shown) in which the axis of the laser processing head 24 is in the vertical direction. The laser processing head 24 is moved up and down so that the axis is in the vertical direction. Supported by the device.

  When the laser oscillating device 22 is driven by the control device 44, the laser light 34 oscillated from the laser oscillating device 22 is collected by the condenser lens 32 and passes through the space portion 29 of the nozzle portion 28. The workpiece 12 is irradiated through the opening 30 at the lower end of the nozzle portion 28. When the laser beam 34 oscillated from the laser oscillation device 22 is irradiated and the workpiece 12 is punched or cut, the control device 44 irradiates the workpiece 12 with the irradiation position of the laser beam 34. The assist gas 40 can be injected to the processed portion 16.

  That is, the assist gas 40 flows from the assist gas supply device 38 into the space portion 29 of the nozzle portion 28 through the introduction pipe 36, and is then injected from the opening 30 at the lower end of the nozzle portion 28 to be processed. Is sprayed on the processed portion 16. Specifically, when drilling or cutting is performed by irradiating the workpiece 12 with the laser beam 34, the assist gas 40 squeezed by the assist gas supply device 38 passes through the introduction pipe 36 and below the laser processing head 24. It flows into the space 29 of the hollow inverted conical nozzle 28 provided at the end.

  The assist gas 40 that has flowed into the space 29 is squeezed downward as it goes through the nozzle portion 28, and is ejected vigorously from the opening 30 and blown onto the processing portion 16 of the workpiece 12. The control device 44 controls the assist gas supply device 38 to process the assist gas 40 injected from the nozzle portion 28 when the drilling or cutting processing is not performed on the workpiece 12. Stop spraying on part 16.

  At the lower end portion of the nozzle portion 28, a capacitance type distance sensor 46 that keeps the distance between the laser processing head 24 and the workpiece 12 constant is provided. The distance sensor 46 is configured to detect a change in capacitance according to a difference in distance between the lower end portion of the nozzle portion 28 and the workpiece 12 and input the detection result to the control device 44. Has been.

  That is, the control device 44 controls the vertical movement of the laser processing head 24 (including the condensing lens 32 and the laser oscillation device 22) based on the detection result of the electrostatic capacitance by the distance sensor 46, so that the laser beam 34. The distance between the workpiece 12 and the lower end opening 30 of the nozzle portion 28 is kept constant during drilling or cutting in the workpiece 12. Note that a technique for holding the distance between the laser processing head 24 and the workpiece 12 constant by the control device 44 using the capacitance type distance sensor 46 is a well-known technique from the past. Description is omitted.

  Next, description will be made on circular drilling of the workpiece 12 by the laser processing apparatus 20 with the above configuration. It is assumed that the workpiece 12 is supported and fixed at a predetermined position of the support table 42 and that the workpiece 12 is subjected to, for example, circular drilling with a diameter of about 50 mm. Further, it is assumed that the control device 44 keeps the distance between the laser processing head 24 and the workpiece 12 constant by changing the capacitance of the distance sensor 46.

  When the laser processing device 20 is operated, the laser light 34 oscillated from the laser oscillation device 22 is collected by the condenser lens 32 and directed from the opening 30 at the lower end of the nozzle portion 28 toward the processing portion of the workpiece 12. Is irradiated. The protective sheet 10 affixed to the surface of the workpiece 12 is cut at the same time when the workpiece 12 is drilled with a laser beam 34 oscillated from the laser oscillation device 22. The assist gas 40 flows from the assist gas supply device 38 into the space portion 29 of the nozzle portion 28 through the introduction pipe 36 and is then squeezed at the opening 30 at the lower end of the thin nozzle portion 28 so that the workpiece 12 The processed part 16 is injected at a high pressure.

  At this time, as indicated by white arrows in FIG. 4, most of the assist gas 40 sprayed at a high pressure on the processed portion 16 of the workpiece 12 passes downward from the processed portion 16 (drilling or cutting processed portion). In addition, the assist gas 40 sprayed at a high pressure on the processed portion 16 of the workpiece 12 hits the workpiece 12 and partly branches. A part of the branched assist gas 40 enters between the workpiece 12 and the protective sheet 10 cut as shown by the black arrows in FIG. 4, and peels the protective sheet 10 from the workpiece 12 as in the prior art. It will rise up.

  However, in the present invention, since the protective sheet 10 is provided with a plurality of through holes 14 at a predetermined interval, the assist gas 40 that enters between the workpiece 12 and the protective sheet 10 and lifts the protective sheet 10 is obtained. Then, it passes through the through hole 14 closest to the processed portion 16 and is discharged to the outside (from between the workpiece 12 and the protective sheet 10 through the through hole 14 and discharged to the outside). That is, most of the assist gas 40 passes downward from the processed portion 16 of the workpiece 12, and a part of the assist gas 40 enters between the workpiece 12 and the protective sheet 10 and is closest to the processed portion 16. From the through-hole 14, it discharge | releases outside from between the to-be-processed object 12 and the protection sheet 10, and it is comprised so that it may not enter between the to-be-processed object 12 and the protection sheet 10 on the separation side.

  Specifically, the through-hole 14 is injected from the tip of the laser processing head 24, and the high-pressure assist gas 40 that has entered between the workpiece 12 and the protective sheet 10 is transferred between the workpiece 12 and the protective sheet 10. The protective sheet 10 is formed in such a size that the protective sheet 10 is released from the workpiece 12 to the outside through the through hole 14 in the direction of the through hole 14 spaced from the processed portion 16. Thereby, since the assist gas 40 does not flow in the direction of the through hole 14 farther from the through hole 14 closest to the processed part 16, the protection sheet 10 in the direction farther from the through hole 14 closest to the processed part 16 is formed. The workpiece 12 will not be peeled off.

  At the time of drilling or cutting the workpiece 12 by the laser beam 34, the protective sheet 10 is peeled off only in the vicinity of the drilled portion 16 as shown in FIGS. 5 and 6 (the protective sheet 10 is The protective sheet 10 is not further peeled off until the through hole 14 closest to the processed portion 16 is peeled off). Thus, even when the workpiece 12 is drilled or cut by the laser beam 34 and then bent or the like, the surface of the workpiece 12 (protection) is protected by the bending apparatus. It is possible to prevent the sheet 10 from being scratched.

  In this way, when the laser processing apparatus 20 performs the required laser processing to irradiate the laser beam 34 while spraying the assist gas 40 on the processing portion 16 of the workpiece 12, the protective sheet 10 is, for example, the surface of the protective sheet 10 as shown in FIG. If the workpiece 12 affixed to the protective sheet 10 is used, the assist gas 40 that has entered between the workpiece 12 and the protective sheet 10 can be discharged to the outside through a plurality of through holes 14 provided in the protective sheet 10. . Specifically, since the preferable interval between the through holes 14 is about 1.00 mm, the dimension that the protective sheet 10 floats is the dimension from the processed portion 16 to the through hole 14 (about 1.00 mm).

  As a result, the protective sheet 10 affixed to the workpiece 12 by the wind pressure of the high-pressure assist gas 40 ejected from the tip of the laser processing head 24 is peeled off from the processing portion 16 with a large size and lifted. Can be prevented in advance. Accordingly, there is a problem that the melt of the protective sheet 10 adheres to the tip of the laser processing head 24 as in the prior art, and the inside of the opening 30 at the lower end of the nozzle portion 28 serving as the outlet of the assist gas 40 is deformed. Can be prevented. Moreover, the discharge direction of the assist gas 40 injected from the opening 30 changes, and the cutting failure of the workpiece 12 occurs, and the nozzle portion 28 of the laser processing head 24 is caught by the protective sheet 10 that is lifted with a large size. Accordingly, it is possible to prevent inconveniences such as the stop sensor working and the cutting processing operation sometimes stopping.

  In particular, the diameter of the through hole 14 is 0.25 mm or more and 2.00 mm or less, and the interval between the through holes 14 is arranged at an interval of 1.00 mm or more and 5.00 mm or less. When drilling or cutting is performed on the workpiece 12, it is possible to reliably prevent the disadvantage that the protective sheet 10 is peeled off from the processed portion 16 by a large dimension and is lifted over the interval between the through holes 14 as in the prior art. Become. Further, since the protective sheet 10 is not peeled beyond the distance between the through holes 14 even by the wind pressure of the high-pressure assist gas 40 injected from the tip of the laser processing head 24, the workpiece 12 is perforated or cut. Thereafter, even when bending is performed, it is possible to prevent the surface of the workpiece 12 from being scratched by the bending apparatus, and it is possible to maintain a clean appearance. As a result, the laser machining accuracy can be improved and the appearance can be maintained in a clean state, so that the commercial value of the laser-machined workpiece 12 can be greatly improved. Therefore, the convenience of the protection sheet 10 stuck to the workpiece 12 and the workpiece 12 to which the protection sheet 10 is stuck can be greatly improved.

  Next, FIGS. 7, 8 and 9 show a protective sheet 10 according to another embodiment of the present invention. The protective sheet 10 has substantially the same configuration as the above-described embodiment. Hereinafter, different parts will be described. The same parts as those in the above-described embodiment are denoted by the same reference numerals, and description thereof is omitted.

  As shown in FIG. 7, the protective sheet 10 is provided with a large number of cuts 18 as penetrating parts that function in the same manner as the through holes 14. The cut 18 is ejected from the tip of the laser processing head 24, and the high-pressure assist gas 40 that has entered between the workpiece 12 and the protective sheet 10 is transferred from between the workpiece 12 and the protective sheet 10 to the outside. The protective sheet 10 is formed so as to be released from the workpiece 12 so as not to peel from the cut 18 in the direction of the cut 18 that is separated from the processed portion 16.

  Specifically, the cut line 18 is cut through the front and back surfaces of the protective sheet 10 with a sharp blade, and the cut length dimension B1 (the length dimension from one end of the cut line 18 to the multiple ends) is about 1. When viewed from the lateral direction of 50 mm to 2.00 mm, it has a negative shape. The protective sheet 10 is provided with a plurality of -shaped cuts 18, and the cuts 18 are arranged at intervals of about 3.00 mm to 4.00 mm in the Y-axis direction (vertical direction in FIG. 7). Specifically, the proximity-side interval B2 between the ends of both cuts 18 adjacent in the Y-axis direction is arranged at a distance of about 3.00 mm to 4.00 mm.

  Further, the cut line 18 is arranged with an interval B3 in the X-axis direction (left-right direction in FIG. 7) of about 3.00 mm. Specifically, a plurality of cuts 18 are arranged at intervals of about 3.00 mm to 4.00 mm in the Y-axis direction, and a plurality of cuts 18 arranged at the Y-axis direction are arranged in the X-axis direction at intervals of about 3.00 mm. Has been. The plurality of cuts 18 arranged in the Y-axis direction are arranged between the plurality of cuts 18 arranged in the adjacent Y-axis direction. The cut lines 18 are arranged in a staggered pattern. The plurality of cuts 18 formed and arranged in this way are ejected from the tip of the laser processing head 24, and the high-pressure assist gas 40 that has entered between the workpiece 12 and the protective sheet 10 is supplied to the workpiece. It can escape efficiently from between 12 and the protective sheet 10 to the outside.

  Next, the protective sheet 10 provided with the cut line 18 having another shape will be described with reference to FIG. As shown in FIG. 8, the protective sheet 10 is provided with a large number of cuts 18 as penetrating parts that function in the same manner as the through holes 14. The cut 18 is also injected from the tip of the laser processing head 24 and the high-pressure assist gas 40 that has entered between the workpiece 12 and the protective sheet 10 is transferred from between the workpiece 12 and the protective sheet 10 to the outside. The protective sheet 10 is formed so as to be released from the workpiece 12 so as not to peel off from the cut 18 in the direction of the cut 18 separated from the processed portion 16.

  Specifically, the cut 18 is cut through the front and back surfaces of the protective sheet 10 with a sharp blade, and the length of the cut (the length from one end of the cut 18 to the other end) is a dimension C1 in the Y-axis direction. Is formed in a positive shape (plus shape) in which the dimension C3 in the X-axis direction is approximately 1.00 mm to 2.50 mm. The protective sheet 10 is provided with a plurality of + -shaped cuts 18. These cuts 18 are arranged at predetermined intervals throughout the protective sheet 10, and the spacing C2 between adjacent cuts 18 in the Y-axis direction. The distance C4 in the X-axis direction is 1.00 mm to 5.00 mm (the distance between the edge of the adjacent through hole 14). The plurality of cuts 18 formed and arranged in this way are ejected from the tip of the laser processing head 24, and the high-pressure assist gas 40 that has entered between the workpiece 12 and the protective sheet 10 is supplied to the workpiece. It can escape efficiently from between 12 and the protective sheet 10 to the outside.

  Next, the protective sheet 10 provided with the cut line 18 having another shape will be described with reference to FIG. As shown in FIG. 9, the protective sheet 10 is provided with a number of cuts 18 as penetrating parts that function in the same manner as the through holes 14. The cut 18 is also injected from the tip of the laser processing head 24 and the high-pressure assist gas 40 that has entered between the workpiece 12 and the protective sheet 10 is transferred from between the workpiece 12 and the protective sheet 10 to the outside. The protective sheet 10 is formed so as to be released from the workpiece 12 so as not to peel off from the cut 18 in the direction of the cut 18 separated from the processed portion 16.

  Specifically, the cut line 18 is torn through the front and back surfaces of the protective sheet 10 with a sharp blade, and the torn shape is substantially Y-shaped (radially spaced in three directions). The length D1 (length from the center extending radially to the end) of each piece of the cut 18 in the three directions torn is approximately Y-shaped formed to be about 0.50 mm to 1.00 mm. Presents. The protective sheet 10 is provided with a plurality of substantially Y-shaped cuts 18, and these cuts 18 are arranged at predetermined intervals throughout the protective sheet 10, and the intervals in the Y-axis direction where the cuts 18 are adjacent to each other. D2 (the distance between the adjacent edge of the cut 18 adjacent to the Y-axis direction) is 3.00 mm to 4.00 mm, and the distance D3 in the X-axis direction is 1.00 mm to 5.00 mm (adjacent. The distance between the center of the cut 18 and the center) is preferably 4.00 mm to 5.00 mm. The plurality of cuts 18 formed and arranged in this way are ejected from the tip of the laser processing head 24, and the high-pressure assist gas 40 that has entered between the workpiece 12 and the protective sheet 10 is supplied to the workpiece. It can escape efficiently from between 12 and the protective sheet 10 to the outside. When the interval D3 in the X-axis direction is narrower than 4.00 mm, adjacent cuts overlap or are too close, so the cuts 18 are arranged in a staggered manner and cuts adjacent in the Y-axis direction. What is necessary is just to prevent that 18 overlaps.

  Then, the protective sheet 10 provided with a plurality of cut lines 18 is affixed to the surface of the workpiece 12, and the workpiece 12 is punched or cut by the laser beam 34 of the laser processing apparatus 20 as described above. When a high-pressure assist gas 40 is jetted from the tip of the laser processing head 24 to the workpiece 12 during drilling or cutting with the laser beam 34, a part of the assist gas 40 is cut. The workpiece 12 and the protective sheet 10 are inserted. Since the assist gas 40 that has entered between the workpiece 12 and the protective sheet 10 is released to the outside from the cut 18, the protective sheet 10 has a larger dimension in the direction of the cut 18 that is farther from the processed portion 16 than the cut 18. It is possible to prevent inconveniences such as peeling off and floating.

  Further, when drilling or cutting of the workpiece 12 is performed by the laser beam 34 of the laser processing apparatus 20, when the cut 18 is cut by the laser beam 34, the cut 18 is turned by the assist gas 40, and the cutting process is performed. The assist gas 40 can escape to the outside from the part and the part where the cut 18 is turned up. Thus, by providing a plurality of cuts 18 in the protective sheet 10, the protective sheet 10 attached to the workpiece 12 is processed by the wind pressure of the high-pressure assist gas 40 injected from the tip of the laser processing head 24 as described above. It is possible to prevent inconveniences such as peeling off from the portion 16 with a large size and floating.

  In particular, since the cut 18 is not a hole (through hole 14), it is possible to prevent dust and the like from adhering to the through hole 14 (hole). Further, in the through hole 14, sand or the like may enter the hole (through hole 14), and there is a concern that the workpiece 12 may be damaged, but by making the through hole 14 a cut 18, Such concerns can be dispelled. Thereby, even if the workpiece 12 to which the protective sheet 10 is stuck is left standing for a long period of time, it is possible to reliably prevent inconveniences such as the cut 18 portion becoming dirty and the commercial value of the workpiece 12 being impaired. Therefore, the convenience of the workpiece 12 having the protective sheet 10 attached to the surface can be greatly improved.

  In addition, the melt of the protective sheet 10 adheres to the tip of the laser processing head 24 as in the prior art, and the melt causes the inside of the opening 30 at the lower end of the nozzle portion 28 that becomes the outlet of the assist gas 40 to be deformed. Can be prevented in advance. As a result, the discharge direction of the assist gas 40 injected from the opening 30 of the laser processing head 24 changes due to the melt of the protective sheet 10 attached to the lower end of the nozzle portion 28, and cutting failure of the workpiece 12 occurs. The protective sheet 10 is lifted with a large dimension by the injected assist gas 40, and the nozzle part 28 of the laser processing head 24 is caught on the protective sheet 10 to act as a stop sensor, so that the cutting operation is performed. It is possible to reliably prevent inconveniences such as sometimes stopping.

  In the embodiment, the workpiece 12 is described as a metal plate such as a stainless steel plate, a steel plate, an aluminum plate, or a copper plate. However, the workpiece 12 is not limited to a metal plate, and may be a synthetic resin or a plywood. There is no problem. In this case, when the workpiece 12 is a synthetic resin, plywood, or the like, the workpiece 12 is irradiated with the laser beam 34 while the assist gas 40 is blown from the laser processing device 20 to the processing portion 16 to punch or cut the workpiece 12. When processing, it can prevent reliably that the protective sheet 10 stuck on the surface, such as a synthetic resin and a plywood, peels off and floats.

  In the embodiment, the through hole 14 is described as a circular hole. However, the through hole 14 is not limited to the circular hole, and the assist sprayed from the laser processing apparatus 20 onto the processing portion 16 of the workpiece 12. As long as the gas 40 can be passed, the through hole 14 may be oval, triangular, square, polygonal or the like. Thereby, since the assist gas 40 sprayed to the process part 16 of the to-be-processed object 12 from the laser processing apparatus 20 can be passed, the problem that the protection sheet 10 peels can be prevented beforehand.

  In the embodiment, a plurality of through-holes 14 (circular holes in the embodiment) having a diameter of about 0.25 mm or more and 2.00 mm or less, preferably 0.50 mm, penetrating the front and back of the protective sheet 10 are formed and each through-hole is formed. Although the holes 14 are arranged at intervals of 1.00 mm or more and 5.00 mm or less, preferably 1.00 mm, the interval between the through holes 14 is the assist sprayed from the laser processing apparatus 20 onto the processing portion 16 of the workpiece 12. If the gas 40 passes and the protective sheet 10 is not peeled off, the through holes 14 can be made as small as possible, and the interval between the through holes 14 can be made as small as possible.

  Moreover, although the shape and dimension of the workpiece 12 to which the protective sheet 10 and the protective sheet 10 were affixed were described in the embodiment, the gist of the protective sheet 10 and the workpiece 12 to which the protective sheet 10 was affixed does not depart. Needless to say, the shape and dimensions may be changed within the range. Of course, the present invention is not limited to the above-described embodiments, and the present invention is effective even when various other modifications are made without departing from the spirit of the present invention.

DESCRIPTION OF SYMBOLS 10 Protective sheet 12 Work piece 14 Through-hole 16 Processed part 18 Cut 20 Laser processing apparatus 22 Laser oscillation apparatus 24 Laser processing head 28 Nozzle part 30 Opening part 32 Condensing lens 34 Laser light 36 Introducing pipe 38 Assist gas supply apparatus 40 Assist Gas 42 Support table 44 Controller 46 Distance sensor

Claims (6)

  A protective sheet that is attached to a workpiece to be subjected to the required laser processing by irradiating laser light while blowing assist gas to the processing portion by a laser processing device, and the through portions that penetrate the front and back surfaces have a predetermined interval. A protective sheet for laser-worked workpieces, wherein a plurality of protective sheets are provided.   2. The laser processed workpiece according to claim 1, wherein the through-hole is a through-hole penetrating the front and back of the protective sheet, and the diameter of the through-hole is 0.25 mm or more and 2.00 mm or less. Worksheet protection sheet.   The diameter of the said through-hole is 0.50 mm, The protection sheet for laser-working workpieces of Claim 2 characterized by the above-mentioned.   The said penetration part is a cut | interruption which penetrates the front and back of the said protection sheet, The protection sheet for laser processing workpieces of Claim 1 characterized by the above-mentioned.   The said penetration part is arrange | positioned by the space | interval of 1.00 mm or more and 5.00 mm or less, The protection sheet for laser processing workpieces in any one of Claims 1 thru | or 4 characterized by the above-mentioned.   A laser-machined workpiece, wherein the protective sheet for a laser-machined workpiece according to any one of claims 1 to 5 is attached to a surface.

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