JP2012130932A - Laser processing apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent the penetration rate of through-hole machining from decreasing due to such factors that the output variation of a laser oscillator, the size variation of the thickness of a workpiece, high or low distribution density of machined holes, a location on the workpiece, etc., when the through-hole machining is applied to a printed board with a copper foil by a conventional processing apparatus.SOLUTION: A workpiece heating layer is provided on a placing part where the workpiece is retained during laser machining, and the workpiece is heated while being suction-fixed. In addition, a heating plate is installed on an adjusting table where the position of the workpiece is adjusted before machining, and the temperature of the workpiece is raised while standing by before machining.

Description

  The present invention relates to a laser processing apparatus that performs processing by irradiating a laser, and more particularly, to a laser processing apparatus that performs drilling in a printed board with a copper foil.

  In recent years, with the miniaturization, high integration, and composite modularization of parts, the drilling of the base material of those parts has also become smaller in diameter, and has become difficult with conventional processing methods. In order to solve these problems, drilling using a laser is increasing. In the drilling of a workpiece by laser, there are roughly classified two types, that is, through-hole processing for forming a through hole in the workpiece and blind hole processing for forming a non-through hole in the workpiece.

  FIG. 4 is a cross-sectional view illustrating a configuration of a workpiece mounting portion of the laser processing apparatus according to the related art.

  In the drawing, a movable mounting portion 812 and an outer peripheral mounting portion 816 divided up and down are provided. An outer peripheral suction hole 814 is formed in the outer peripheral placement portion 816, and a placement portion suction hole 813 is formed in the divided movable placement portion 812. The workpiece 811 is placed on the upper part of the divided movable placing part 812 and outer circumference placing part 816 and is sucked and held. The divided movable mounting portions 812 have a structure that can be individually moved in the vertical direction, and are moved up and down by a lift drive unit such as an air cylinder.

  At the time of blind hole processing, the movable mounting portion 812 is in a state where all the suction portions are raised. Then, the work piece 811 is suction-fixed and processed using the entire surface of the mounting portion. At the time of through-hole processing, as shown in FIG. 4, laser processing is performed in a state where only the divided movable mounting portion 812 corresponding to the lower portion of the processing is lowered.

  With the configuration described above, damage to the mounting portion due to the laser during through-hole processing is prevented while maintaining the flatness of the workpiece (for example, see Patent Document 1).

International Publication No. 2009/001497

  However, when through-hole processing of a printed circuit board with copper foil is performed with a conventional laser processing device, the output fluctuation of the laser oscillator, the thickness variation of the workpiece, the size of the distribution density of the processed holes, There is a problem that the penetration rate of through-hole processing decreases due to factors such as the location of the through hole.

  This is because an insulating layer made of a polymer material or glass, which is a material constituting a printed circuit board, has good workability and reaches the copper foil on the back side when the material temperature at the time of laser irradiation rises from room temperature. While laser output increases and penetrability increases, when the temperature of the insulating material decreases, workability decreases, the laser light reaching the back surface weakens, energy that penetrates the copper foil decreases, and copper foil penetrability decreases It is generated from doing.

  In general, when a printed circuit board fixed on a mounting table made of a metal housing is processed, the temperature of the workpiece immediately before processing is almost the same as the room temperature due to the effect of the mounting table having a large heat capacity. For example, the laser irradiation continues in the part where the processing hole density is high, and the temperature of the surrounding workpiece constituent material increases and the workability is improved, but the temperature increase is small in the part where the density is low, so the laser output decreases. When fluctuations occurred, through-hole machining could not be realized due to a decrease in workability.

  The present invention provides a laser processing apparatus that realizes preventing a decrease in the penetration rate by increasing the temperature of a workpiece when a through-hole processing is performed on a printed board with a copper foil by a laser beam. Objective.

  In order to solve the above-described problems, a laser processing apparatus according to the present invention has a processing head unit that laser-processes a workpiece, and a plurality of divided movable placement units that move up and down to hold the workpiece. And a table that drives the workpiece placement unit in the XY directions, and a heating unit is provided on a surface of the plurality of movable placement units that contacts the workpiece.

  Preferably, the laser processing apparatus of the present invention further includes a position adjusting unit that adjusts a mounting position of the workpiece before the step of mounting the workpiece on the workpiece mounting unit, A heating unit is provided on the surface in contact with the workpiece.

  With the above configuration, the laser processing apparatus of the present invention can maintain the temperature so that the laser processing property of the constituent material of the workpiece is increased during the through-hole processing of the workpiece, thereby varying the laser output. Further, it is possible to prevent the penetration rate of the workpiece from being lowered due to the influence of the distribution density of the processed holes or the like.

The perspective view which shows schematic structure of the laser processing apparatus which concerns on an example of embodiment of this invention. Schematic configuration diagram including a laser processing apparatus and a workpiece transfer apparatus according to an example of an embodiment of the present invention The perspective view which shows the structure of the movable mounting part which concerns on an example of embodiment of this invention. Sectional drawing which shows the structure of the mounting part of the laser processing apparatus which concerns on a prior art

  An example of an embodiment according to the laser processing apparatus of the present invention will be described with reference to the drawings.

(Embodiment 1)
FIG. 1 is a perspective view showing a schematic configuration of a laser processing apparatus 100 according to an example of an embodiment of the present invention.

  In FIG. 1, a laser oscillator 101 emits a laser 102 by emitting a laser inside. The direction of the emitted laser 102 is changed by a mirror 103. The laser 102 whose direction has been changed by the mirror 103 is adjusted in density (laser diameter) by a collimator lens 104 arranged in the traveling direction thereof, and the shape of the laser 102 is shaped by a mask 105, and the iris 106 emits miscellaneous light. It is suppressed.

  The laser 102 that has passed through the iris 106 is positioned by a galvano X mirror 109 for oscillating in the X-axis direction and a galvano Y mirror 110 for oscillating the laser 102 reflected by the galvano X mirror 109 in the Y-axis direction. Further, the apparatus is configured such that the laser 102 reflected by the galvano Y mirror 110 is condensed by the fθ lens 107 and irradiated to the processing point of the workpiece 111.

  A control controller 108 for controlling the galvano X mirror 109, the galvano Y mirror 110, and the laser oscillator 101 is provided.

  A plurality of workpieces 111 are placed on a plurality of movable placement parts 121 and outer circumference placement parts 123. The workpiece placing unit 120 is composed of the movable placing unit 121 and the outer circumferential placing unit 123. The movable mounting portion 121 is provided with a plurality of mounting portion suction holes 122, and the outer peripheral mounting portion 123 is also provided with an outer peripheral suction hole 124. The workpiece 111 is sucked and held by evacuation from the placement portion suction hole 122 and the outer periphery suction hole 124.

  The movable mounting parts 121 are each supported by a pair of movable mounting part lifting cylinders 125. In this embodiment, the movable mounting part raising / lowering cylinder 125 uses an air cylinder controlled by air pressure, and each movable mounting part 121 can be moved up and down independently.

  A space between the workpiece mounting unit 120 that holds the workpiece 111 and the machining table 115 is a lower dust suction device 112 that collects machining waste generated at the lower portion of the workpiece 111 during laser machining by airflow. Has the function of dust.

  An upper dust suction device 130 is installed on the laser irradiation surface side above the workpiece 111. The upper dust suction device 130 is provided so as to surround the irradiation range of the laser 102 controlled by the galvano X mirror 109 and the galvano Y mirror 110, and the laser processing is performed by sucking the internal air from a hole provided in a part thereof. At this time, the processing waste generated on the workpiece 111 is collected and discharged.

  FIG. 2 is a schematic configuration diagram including a laser processing apparatus 100 according to an example of an embodiment of the present invention and a workpiece 111 conveying apparatus.

  The processing table 115 is mainly composed of two blocks, a Y table 116 and an X table 118. The Y table 116 is configured to place the workpiece placement unit 120 and a set of configurations associated therewith and move in the Y direction. The movement in the Y direction is performed by driving the Y-axis movement motor 117 to rotate the ball screw and sliding the Y table 116 along with the entire set mounted thereon. The X table 118 is configured to further mount the Y table 116 and a set of components mounted thereon and move in the X direction. The movement in the X direction is performed by driving the X axis movement motor 119 to rotate the ball screw and sliding the X table 118 along with the entire set mounted thereon.

  The galvano X mirror 109, the galvano Y mirror 110, which reflects the laser 102 and controls the irradiation position, and the fθ lens 107 which makes the direction of the laser 102 perpendicular to the surface of the workpiece 111 and condenses the machining head unit 135. The processing head portion 135 is attached to the main body frame via a slider, and is movable in the Z direction, that is, the vertical direction.

  In the vicinity of the processing table 115, a loading-side workpiece lifting / lowering unit 201 for placing an unprocessed workpiece 111 to be processed, a unloading-side workpiece lifting / lowering unit 241 for placing a processed workpiece 111, and a workpiece position adjustment unit 220 are installed. Has been. A workpiece heating plate 221 is provided on the workpiece position adjusting unit 220, and the workpiece heating plate 221 can appropriately generate heat by a workpiece heating power source 222 separately installed via a heating power cable 223.

  A carry-in head 202 is provided to carry the workpiece 111 from the carry-in work lifting / lowering unit 201 to the work position adjusting unit 220 and from the work position adjusting unit 220 to the work placing unit 120. The carry-in head 202 sucks the workpiece 111 at a predetermined position, moves along the guide, and conveys the workpiece 111.

  An unloading head 242 is provided to transfer the workpiece 111 from the workpiece mounting unit 120 to the unloading-side workpiece lifting / lowering unit 241. Similar to the carry-in head 202, the carry-out head 242 attracts the workpiece 111 at a predetermined position, moves along the guide, and conveys the workpiece 111.

  Next, the configuration of the movable mounting portion 121 among the characteristic configurations of the present invention will be described in detail.

  FIG. 3 is a perspective view showing a configuration of the movable mounting portion 121 according to an example of the embodiment of the present invention. In FIG. 3, one of a plurality of movable mounting portions that hold the workpiece 111 is taken out, and its configuration is shown.

  The movable mounting part 121 usually has a smoothness increased so that the height of the laser beam focus focused and irradiated during processing does not change depending on the part of the workpiece, and the negative pressure for vacuum suction. It is made of a metal housing to withstand The movable mounting portion 121 of the present invention includes a movable mounting portion case 304, a suction plate 301 on the upper surface of the movable mounting portion case 304, a suction plate insulating layer 302 coated on the suction plate 301, and a suction plate insulation. A work heating layer 303 is further provided on the layer 302.

  The movable placement unit case 304 and the suction plate 301 are formed of the same material, and the material thereof is formed of a sufficiently rigid material, for example, a metal such as aluminum. The suction plate insulating layer 302 coated on the suction plate 301 is formed of an electrical insulator having heat resistance such as polyimide resin. The work heating layer 303 can be made of a material having a higher electric resistance than that of the movable placement unit case 304 and the suction plate 301, for example, conductive ceramics.

  The workpiece heating layer 303 is connected to the heating power source 311 via the heating wiring 312 so that each workpiece heating layer 303 can be energized independently. The operation of the heating power supply 311 is controlled by a power supply drive switch 314. The suction plate insulating layer 302 prevents current from leaking to the suction plate 301 having a lower electrical resistance than the workpiece heating layer 303. In general, a material having a low electrical resistance has a low thermal conductivity, so that the heat generated by the workpiece heating layer 303 is prevented from flowing to the suction plate 301 before the workpiece 111.

  A plurality of mounting portion suction holes 122 are provided through the suction plate 301, the suction plate insulating layer 302, and the workpiece heating layer 303. An air circulation hole 307 is provided in the movable placement unit case 304. Via the air circulation pipe 306, the air pressure in the space covered by the suction plate 301 and the movable placement part case 304 of each movable placement part 121 can be increased / decreased through the air circulation hole 307. The air flow necessary for pressurization / decompression is controlled by a solenoid valve 305, and the solenoid valve 305 is controlled by a solenoid valve drive switch 313. Thereby, it is comprised by the mounting part adsorption | suction hole 122 so that suction and blowing are possible.

  Note that the heating power supply 311 and related circuits, the air circulation holes 307, the air circulation piping 306, and the circuits related thereto are shown in principle in the drawing, and in an actual apparatus, appropriate operations that do not affect the operation of the apparatus are shown. It is installed at the place. In addition, the above configuration is provided for each of the plurality of movable placement units 121.

  The operation of the laser processing apparatus 100 configured as described above will be described.

  The unprocessed workpieces 111 to be processed are loaded on the carry-in workpiece lifting / lowering unit 201. With the carry-in head 202, one piece is taken out from the workpiece 111 waiting to be processed and loaded on the carry-in workpiece lifting / lowering unit 201 and placed on the workpiece position adjustment unit 220. The workpiece position adjustment unit 220 adjusts the position of the workpiece 111 so that the workpiece 111 can be placed at an appropriate position when the workpiece 111 is placed on the workpiece placement unit 120. The workpiece 111 is waiting on the workpiece position adjustment unit 220 until the end.

  During this time, the work heating power supply 222 is activated, a current flows to the work heating plate 221 via the heating power supply cable 223, and the work heating plate 221 generates heat. Since the workpiece 111 waiting for processing is on the workpiece heating plate 221, the workpiece 111 is heated during standby and the temperature rises. As described above, since the entire workpiece is heated while waiting for processing, the temperature of the workpiece 111 having a large insulating layer and a large heat capacity can be uniformly increased before processing.

  Then, when the previously performed processing is completed and the new workpiece 111 is mounted on the apparatus, the movable mounting portion 121 is placed in a state where the mounting portion suction hole 122 and the outer peripheral suction hole 124 are not sucked. Keep everything up. Then, by moving the processing table 115, the workpiece mounting unit 120 is moved to the mounting position of the workpiece 111.

  After the workpiece 111 is mounted on the workpiece mounting portion 120, the mounting portion suction hole 122 and the outer periphery suction hole 124 are evacuated to suck and hold the lower surface of the workpiece 111. Simultaneously with this suction, the power source drive switch 314 is controlled, and energization is started from the heating power source 311 to the work heating layers 303 on all the movable mounting parts 121. As a result, it is possible to maintain a state in which the entire workpiece 111 is heated. The work heating layer 303 may be energized in advance before the suction, not before the suction, and the work placement unit 120 may be preheated.

  After holding the workpiece 111 is completed, the following operation is started. The movement of the machining table is started in order to move the workpiece placing unit 120 holding the workpiece 111 to the first machining area. The movement of the processing head unit 135 at the origin position to the focal position is started. Only the movable mounting part 121 on the lower surface of the first processing area is switched to the vacuuming of the mounting part suction hole 122 provided in the movable mounting part to blow, and the suction holding and stopping of the lower surface of the workpiece in the part is stopped. Then, the movable mounting portion 121 is lowered. These operations are performed in parallel.

  Each processing area is set within the scan range of the galvanometer mirror, and positioning of the laser processing in the area is performed by controlling the galvanometer mirror. As described above, after the preparation in the first processing area is completed, the galvano X mirror 109 and the galvano Y mirror 110 are controlled to start irradiation of the laser 102 at the hole processing position.

  At this time, since the lowered movable mounting portion 121 is not in contact with the workpiece 111, energization may be stopped only for the workpiece heating layer 303 on the lowered movable mounting portion 121. Further, air flow may be stopped instead of blowing. If the solenoid valve drive switch 313 that opens the solenoid valve 305 and the power drive switch 314 that drives the heating power supply 311 are operated in conjunction with each other, the heating power supply is simultaneously opened when the solenoid valve 305 is opened for adsorption. 311 operates to pass a current through the heating wire 312 to the work heating layer 303, whereby the work heating layer 303 generates heat, and when the adsorption is stopped, the energization of the work heating layer 303 can also be stopped.

  Alternatively, only the current that flows through the work heating layer 303 of the movable mounting part 121 may be increased when the lowered movable mounting part 121 is blown. If it does in this way, the air stream to blow can be heated to higher temperature, and the location which carried out the hole drilling with a laser can be heated more efficiently.

  When the predetermined laser irradiation is completed and all holes in the first processing area are completed, the processing table 115 is moved in the Y direction in this embodiment in order to move to the second processing area. The procedure of a series of operations in the second processing area is the same as described above. The movement is sequentially performed to the third and fourth processing areas, and the process is repeated until the laser processing is completed for all areas where one movable mounting portion 121 is lowered.

  When the laser processing is completed for all the areas where one movable mounting portion 121 is lowered, the following operation is started.

  First, in order to move the workpiece placing unit 120 to the next machining area, the machining table 115 starts to move in the X direction. While stopping the blowing of the movable mounting portion 121 that has already been lowered, the movable mounting portion 121 is lifted, and when the lifting is completed, the mounting portion suction hole 122 provided in the movable mounting portion 121 is evacuated. Then, the workpiece 111 is again held by suction. At this time, the energization of the work heating layer 303 on the movable mounting portion 121 is controlled so as to be in a heating state similar to that of other movable mounting portions. The evacuation of the placement portion suction hole 122 provided in the movable placement portion 121 at a position corresponding to the next processing area is switched to blow. The operation of the workpiece heating layer 303 of the movable mounting portion is the same as that described above. When the lower surface of the workpiece at that location is no longer held, the movable mounting portion 121 at that location is lowered. These operations are performed in parallel.

  Then, after the workpiece 111 arrives at the processing area and is ready in the processing area, the galvano X mirror 109 and the galvano Y mirror 110 are controlled to start irradiation of the laser 102 at the hole processing position.

  The above operation is repeated to process all predetermined areas of the workpiece 111.

  When all the processing of the predetermined area is completed, the following operation is started.

  First, the movement of the machining table 115 is started in order to start the movement to the workpiece removal position. The movement of the machining head unit 135 to the origin is started. While the movable mounting portion 121 that has already been lowered is blown, the movable mounting portion 121 is lifted, and when the lifting is completed, the mounting portion suction hole 122 provided in the movable mounting portion 121 is evacuated. Then, the workpiece 111 is again sucked and held. These operations are performed in parallel.

  When all the operations described above are completed, evacuation of all the placement portion suction holes 122 and all the outer periphery suction holes 124 is stopped. Then, it is confirmed that the workpiece 111 is not attracted and held, and the workpiece 111 processed by the unloading head 242 is stacked on the unloading work lifting / lowering unit 241. Put it on top.

  As described above, in the laser processing apparatus of the present invention, during blind hole processing, laser processing is performed while all units of the workpiece mounting unit 120 are raised, but in the case of through-hole processing, The movable mounting portion 121 at a position where the penetrating laser can reach is positioned below the other mounting portions and removed from the focusing range of the laser 102, so that it is not damaged by the laser. Is processed so as to be adsorbed and held. Switching of which machining method is performed is performed based on the contents of the machining program of the control device of the machining apparatus, although not shown in the figure.

  In the laser processing apparatus of the present invention, with the above configuration, while the workpiece is attracted and fixed on the workpiece mounting portion for processing, the workpiece is heated from the upper surface of the workpiece mounting portion. As a result, the temperature rises to prevent the insulating material as a constituent material from falling from a temperature state suitable for laser processing, and processing can be performed while maintaining the penetrability of the copper foil on the back surface. Moreover, since the whole workpiece is heated, the temperature of the workpiece can be increased uniformly.

  Furthermore, the workpiece waiting to be processed on the workpiece position adjustment unit can receive the heat generated from the heating plate on the upper surface of the position adjustment unit to increase the temperature. It is possible to prevent the temperature from being lowered from a temperature suitable for laser processing, and to perform processing while maintaining the penetrability of the copper foil on the back surface. In this case, since the entire workpiece can be sufficiently heated while waiting for processing, the temperature of the workpiece having a large insulating layer and a large heat capacity can be uniformly increased before processing.

  Note that the number of movable placement units may be determined by design requirements such as the size of the apparatus, and is not limited to an example of the present embodiment.

  INDUSTRIAL APPLICABILITY The present invention can prevent a reduction in the penetration rate in through-hole processing of a printed circuit board with copper foil, and is useful for a laser processing apparatus and the like for improving the yield of laser processing and performing stable through-hole processing. .

DESCRIPTION OF SYMBOLS 100 Laser processing apparatus 101 Laser oscillator 102 Laser 103 Mirror 104 Collimator lens 105 Mask 106 Iris 107 f (theta) lens 108 Control controller 109 Galvano X mirror 110 Galvano Y mirror 111 Workpiece 112 Lower dust suction apparatus 115 Processing table 116 Y table 117 Y axis movement Motor 118 X table 119 X-axis moving motor 120 Work placement portion 121 Movable placement portion 122 Placement portion suction hole 123 Outer periphery placement portion 124 Outer periphery suction hole 125 Movable placement portion lifting cylinder 130 Upper dust suction device 135 Processing head portion 201 Loading side work lifting unit 202 Loading head 220 Work position adjustment unit 221 Work heating plate 222 Work heating power supply 223 Heating power cable 241 Unloading side work lifting unit G 242 Unloading head 301 Suction plate 302 Suction plate insulating layer 303 Work heating layer 304 Movable mounting part case 305 Solenoid valve 306 Air circulation piping 307 Air circulation hole 311 Heating power supply 312 Heating wiring 313 Solenoid valve drive switch 314 Power supply drive switch

Claims (6)

A machining head for laser processing the workpiece, a workpiece placement portion for holding the workpiece by having a plurality of divided movable placement portions that move up and down, and the workpiece placement portion in the XY direction. A laser processing apparatus comprising: a driving table; and a heating unit provided on a surface of each of the plurality of movable placement units that contacts the workpiece. An insulating layer made of an electrical insulator is formed on the upper surface of the movable mounting portion on the side in contact with the workpiece, a high electrical resistance conductive layer is further formed on the insulating layer, and a current is supplied to the conductive layer. The laser processing apparatus according to claim 1, wherein the heating unit is made to flow. The laser processing apparatus according to claim 2, wherein a hole through which air flows is formed on a surface of the movable mounting portion that contacts the workpiece, and suction by the air circulation hole and energization of the heating unit are interlocked. . A hole through which air flows is formed in a surface of the movable mounting portion that contacts the workpiece, and when the movable mounting portion is separated from the workpiece, an air flow is ejected from the air circulation hole and the movable mounting portion is moved. The laser processing apparatus of Claim 1 or 2 which increases the heating amount of the heating part provided in the mounting part. The apparatus further includes a position adjusting unit that adjusts the mounting position of the workpiece before the step of mounting the workpiece on the workpiece mounting unit, and a heating unit is provided on the surface of the position adjusting unit that is in contact with the workpiece. The laser processing apparatus according to claim 1, which is provided. The heating unit is a heat generating plate that generates heat when energized with electricity, and a power supply device that is controlled to energize the heat generating plate while the workpiece is placed on the position adjusting unit is provided. Laser processing equipment.

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