JP2011056522A - Laser beam machining apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a laser beam machining apparatus in which a head part for scanning laser beam transmitted via an optical fiber cable from a body part having a laser beam amplifying means can be miniaturized while suppressing degradation of the machining accuracy. <P>SOLUTION: The laser beam machining apparatus includes a body part 2, and a head part 4 for scanning laser beam transmitted from the body part 2 via an optical fiber cable 3. The head part 4 has a Z scanner 27 capable of adjusting the focal position of the laser beam in the direction of the optical axis, an XY scanner 28 for scanning the laser beam in the direction across the optical axis, and an XY scanner control circuit 31 for controlling the XY scanner 28. The body part 2 has a laser beam amplifier 15 for amplifying the laser beam by using optical fiber which the laser medium is added to a core, and a main control circuit 11 for controlling the Z scanner 27. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to a laser processing apparatus, and more particularly to an improvement of a laser processing apparatus that transmits laser light by an optical fiber cable from a main body having laser light amplification means to a head part that scans the laser light.

  In recent years, as a laser processing apparatus that processes a workpiece by irradiating a laser beam, a Z scanner that not only scans the laser beam in a direction intersecting the optical axis by an XY scanner but also moves the focal position of the laser beam in the optical axis direction Has been proposed (for example, Patent Document 1). The XY scanner scans the laser beam by rotating the two mirrors around the orthogonal rotation axes, whereas the Z scanner moves the lens arranged on the optical path to increase the beam divergence angle. By adjusting, the focal position of the laser beam is moved. Such a head portion having an XY scanner or a Z scanner is desirably small in view of improving workability and space efficiency when installed on a workpiece production line or the like. However, in the laser processing apparatus described in Patent Document 1, a laser oscillation unit that incorporates a solid-state laser for amplifying laser light is provided in the casing of the head unit. Cannot be shorter than the total length. In addition, the laser oscillation unit amplifies the light by reciprocating the laser beam between the mirrors arranged on both sides of the laser medium, ensuring a certain total length to accumulate the energy required for laser processing. Must. For this reason, the total length of the laser oscillation part cannot be made shorter than a certain length.

  In this regard, if the laser oscillation unit is not in the head unit, the head unit can be reduced in size. That is, if the laser oscillation unit is arranged in a main body unit different from the head unit, and the laser light amplified by the laser oscillation unit is transmitted from the main body unit to the head unit to a transmission medium such as an optical fiber cable, the head unit is reduced in size. It is considered that However, in this case, it is extremely difficult to make the laser beam once emitted from the laser oscillation unit in the main body unit enter a transmission medium such as an optical fiber cable. Therefore, a fiber laser that uses a rare earth-doped optical fiber doped with a rare earth element as a laser medium in the core is disposed as a laser optical amplifier in the main body, and the laser optical amplifier and the optical fiber cable are directly connected to each other to thereby amplify the laser. It is conceivable to transmit the laser light from the main body to the head without emitting light outside the optical fiber (for example, Patent Document 2). According to the laser processing apparatus described in Patent Document 2, since the laser optical amplifier is disposed in the main body portion, the length of the head portion can be shortened.

JP 2008-62260 A JP 2000-340872 A

  Recently, further downsizing of the head portion has been demanded. Therefore, a scanner control board provided with a control circuit for controlling the XY scanner and the Z scanner is provided in the main body instead of being provided in the main body, and a drive signal for scanner control is transmitted from the main body to the head. It is conceivable that the data is transmitted. However, there is a problem that the scanning accuracy of the laser beam is blurred due to the influence of noise added during the transmission of the drive signal, and the processing accuracy is lowered.

  The present invention has been made in view of the above circumstances, and a head unit that scans a laser beam transmitted from a main body unit having a laser beam amplifying unit via an optical fiber cable is suppressed while suppressing a decrease in processing accuracy. An object of the present invention is to provide a laser processing apparatus that can be realized. In particular, it is an object of the present invention to provide a laser processing apparatus capable of reducing the size of a head unit having an XY scanner or a Z scanner.

  A laser processing apparatus according to a first aspect of the present invention includes a main body having laser light amplification means for amplifying laser light using an optical fiber having a laser medium added to a core, and transmitted from the main body via an optical fiber cable. A Z scanner capable of adjusting a focal position of the laser beam in the optical axis direction, and an XY scanner that scans the laser beam in a direction intersecting the optical axis. And an XY scanner control means for controlling the XY scanner, and the main body is configured to have a Z scanner control means for controlling the Z scanner.

  According to such a configuration, since the Z scanner control means for controlling the Z scanner of the head section is provided in the main body section, the head section can be reduced in size compared to the case where the Z scanner control means is provided in the head section. Can do. Further, since the XY scanner control means for controlling the XY scanner is provided in the head unit, it is possible to suppress the addition of noise to the drive signal for controlling the XY scanner. Here, in the focus position adjustment using the Z scanner, even if a focus position error occurs due to the influence of noise added to the drive signal, the influence of the error is slight due to the focal depth of the laser beam. On the other hand, in the X-direction and Y-direction scanning using the XY scanner, the influence of the scanning position error due to the influence of noise becomes large. In the laser processing apparatus according to the present invention, focusing on such characteristics of the scanner, the control unit of the scanner is allocated to the head portion and the main body portion, thereby reducing the head portion size while suppressing a decrease in processing accuracy. be able to.

  In the laser processing apparatus according to the second aspect of the present invention, in addition to the above configuration, the head portion is emitted from the first frame to which the optical fiber cable is attached so that the optical axis intersects the frame surface, and from the end surface of the optical fiber cable. A return light suppression means that transmits the laser light and suppresses return light; a second frame in which the frame surface is disposed opposite to the frame surface of the first frame with the return light suppression means interposed; The frame and the second frame are connected to each other, and the frame surface has a third frame arranged substantially parallel to the longitudinal direction of the return light suppression means. The XY scanner control means has an X-direction scanning control circuit. An X scanner control board provided and a Y scanner control board provided with a control circuit for Y-direction scanning, the X scanner control board and the Y scanner Configured control board is disposed substantially parallel to the said frame surface of the third frame.

  According to such a configuration, the X scanner control board provided with the control circuit for X direction scanning and the Y scanner control board provided with the control circuit for Y direction scanning are substantially the frame surface of the third frame. Since they are arranged in parallel, the head portion can be thinned in the direction intersecting the frame surface of the third frame. Further, by allocating the XY scanner control means to the X scanner control board and the Y scanner control board, compared with the case where the control circuit for X direction scanning and the control circuit for Y direction scanning are provided on one board, The size of the substrate can be reduced.

  In the laser processing apparatus according to a third aspect of the present invention, in addition to the above configuration, the Z scanner is disposed on the side opposite to the return light suppression means with respect to the second frame so that the optical axis is substantially parallel to the frame surface of the second frame. The XY scanner is arranged between the first frame and the second frame, and the laser beam that has passed through the Z scanner is configured to be incident substantially parallel to the longitudinal direction of the return light suppression unit. According to such a configuration, since the distance between these frames is shorter than when the Z scanner is disposed between the first frame and the second frame, the length of the head portion can be shortened.

  In addition to the above configuration, the laser processing apparatus according to the fourth aspect of the present invention is configured such that the X scanner control board is disposed on the opposite side of the Y scanner control board with respect to the third frame. According to such a configuration, since the X scanner control board and the Y scanner control board are arranged on the opposite sides with respect to the third frame, a heat source such as an amplifier that supplies a drive current to the XY scanner is used as the scanner. The control boards can be spaced apart. As a result, the heat radiation effect of the X scanner control board and the Y scanner control board can be enhanced.

  A laser processing apparatus according to a fifth aspect of the present invention, in addition to the above-described configuration, receives the laser light that has passed through the return light suppression unit, and a power monitor that detects laser power includes the return light suppression unit with respect to the second frame. Are configured to be disposed on opposite sides. According to such a configuration, since the distance between these frames is shorter than when the power monitor is disposed between the first frame and the second frame, the length of the head portion can be shortened. In particular, since the laser light that has passed through the return light suppression means is received as it is by the power monitor, the laser power after passing through the return light suppression means is reflected by the mirror and then received by the power monitor. The length of the head portion can be shortened by an amount corresponding to the size of the light receiving surface.

  According to the laser processing apparatus of the present invention, since the Z scanner control means for controlling the Z scanner of the head portion is provided in the main body portion, the head portion can be reduced in size compared to the case where the Z scanner control means is provided in the head portion. can do. Further, since the XY scanner control means for controlling the XY scanner is provided in the head unit, it is possible to suppress the addition of noise to the drive signal for controlling the XY scanner. Therefore, it is possible to reduce the size of the head unit that scans the laser beam transmitted from the main body unit having the laser beam amplification means via the optical fiber cable, while suppressing a decrease in processing accuracy.

It is the block diagram which showed an example of schematic structure of the laser processing apparatus 100 by embodiment of this invention. It is explanatory drawing which showed an example of the scanning operation | movement of the Z direction in the laser processing apparatus 100 of FIG. 1, and the mode that the distance between lenses is shortened and a focus position moves away is shown. It is explanatory drawing which showed an example of the scanning operation | movement of the Z direction in the laser processing apparatus 100 of FIG. 1, and the mode that the distance between lenses is lengthened and a focus position approaches is shown. FIG. 2 is a development view schematically showing a configuration example of the head unit 4 of the laser processing apparatus 100 of FIG. 1, and shows the inside of the head unit 4. It is the perspective view which showed the structural example of the head part 4 of the laser processing apparatus 100 of FIG. 1, and the mode that the head part 4 from which the rear cover was removed was seen from the right front is shown. It is the perspective view which showed the structural example of the head part 4 of the laser processing apparatus 100 of FIG. 1, and the mode that the head part 4 from which the rear cover was removed was seen from the left front is shown. It is the perspective view which showed the structural example of the head part 4 of the laser processing apparatus 100 of FIG. 1, and the mode that the head part 4 from which the rear cover was removed was seen from the lower side is shown. It is the perspective view which showed the structural example of the head part 4 of the laser processing apparatus 100 of FIG. 1, and the mode that the head part 4 from which the front cover 4a was removed was seen from the left front is shown. FIG. 9 is a diagram illustrating a configuration example of the head unit 4 in FIG. FIG. 2 is a perspective view illustrating a configuration example of the head unit 4 of the laser processing apparatus 100 in FIG. 1, and illustrates an optical path of laser light around the dichroic mirror 26. It is the top view which showed the structural example of the head part 4 of FIG. 10, and the mode that the head part 4 was seen from the top is shown.

<Laser processing equipment>
FIG. 1 is a block diagram showing an example of a schematic configuration of a laser processing apparatus 100 according to an embodiment of the present invention. The laser processing apparatus 100 is a processing apparatus that processes a workpiece W by scanning a laser beam, and includes a console 1, a main body 2, an optical fiber cable 3, and a head 4. The console 1 is an input device for inputting machining conditions of the workpiece W and the like.

  The main body 2 is a laser oscillator unit including a main control circuit 11, a workpiece processing information storage unit 12, a power supply circuit 13, an excitation light source 14, and a laser light amplifier 15, and performs laser oscillation control and laser light scanning control. Is going. The excitation light source 14 is a light source device that generates excitation light for exciting the laser medium and emits the excitation light to the laser light amplifier 15, and includes a light emitting element such as an LD (laser diode) and a condenser lens.

  The laser light amplifier 15 is a fiber laser that amplifies laser light using an optical fiber having a laser medium added to the core, and generates high-power laser light with high energy density. The laser light amplifier 15 is composed of a master oscillator unit that generates low-output seed light, a power amplifier unit that amplifies the seed light, a pumping light source device, an isolator, and the like, and is directly connected to the optical fiber cable 3. The master oscillator unit and the power amplifier unit are configured by a rare earth-doped optical fiber to which a rare earth element such as ytterbium (Yb) is added as a laser medium.

  The laser light amplifier 15 amplifies the laser light by the induced radiation of the laser medium excited by the excitation light, and transmits the amplified laser light to the optical fiber cable 3 as it is without emitting it out of the optical fiber.

  The laser optical amplifier 15 is provided with, for example, a Q switch for controlling laser oscillation. By switching the Q switch, continuous oscillation can be converted into pulse oscillation, and a pulse wave with high peak power is generated. can do. Note that the laser optical amplifier 15 may not be provided with a Q switch like an oscillator capable of pulse oscillation by directly turning on or off an LD that generates seed light.

  The optical fiber cable 3 is a delivery fiber that transmits the laser light amplified by the laser light amplifier 15 to the head unit 4. The head unit 4 is a scanner unit that scans the laser beam transmitted from the laser beam amplifier 15 of the main unit 2 via the optical fiber cable 3, and emits the laser beam toward the workpiece W.

  The head unit 4 includes an optical isolator 21, a beam expander 22, a beam sampler 23, a shutter 24, a photo interrupter 25, a dichroic mirror 26, a Z scanner 27, an XY scanner 28, a power monitor 29, a guide light source 30, and an XY scanner control circuit. 31.

  The optical isolator 21 is a return light suppression unit that transmits the laser light emitted from the end face of the optical fiber cable 3 and suppresses the return light. The optical isolator 21 emits the laser light transmitted through the optical fiber cable 3 to the beam expander 22. To do. With this optical isolator 21, the laser light is transmitted only in the forward direction, with the direction from the end surface on the optical fiber cable 3 side of the optical isolator 21 toward the end surface on the beam expander 22 side being forward, and transmission in the reverse direction is restricted. Is done.

  Such an optical isolator 21 includes, for example, an aperture, a polarizer, and a Faraday rotator, and is a device that is long in the optical axis direction. The aperture is a blocking plate for limiting the passing light. The polarizer is a rod-shaped optical element made of a birefringent crystal. A Faraday rotator is a magneto-optical element that rotates a plane of polarization by applying a magnetic field.

  The beam expander 22 is a beam diameter enlarging mechanism that enlarges the beam diameter of the laser light, and is arranged with the optical isolator 21 and the optical axis aligned. The beam expander 22 includes a plurality of lenses arranged on the optical path, and converts the beam diameter to a desired value by adjusting the distance between the lenses. The beam sampler 23 is an optical element that reflects part of the laser light that has passed through the beam expander 22 toward the dichroic mirror 26 and transmits the other part to the power monitor 29 side.

  The power monitor 29 is a laser power detection sensor that receives the laser beam transmitted through the beam sampler 23 and detects the laser power. The main control circuit 11 in the main body 2 uses the detection result of the laser power as a power level detection signal. Output to. As such a power monitor 29, for example, a thermopile or a photodiode is used.

  The shutter 24 is a blocking device for blocking the laser light as necessary, and is configured by a driving mechanism that moves the blocking plate and the blocking plate. The shutter 24 is disposed between the beam sampler 23 and the dichroic mirror 26.

  The photo interrupter 25 is an optical sensor that optically detects whether or not the shutter 24 is closed. The dichroic mirror 26 is an optical element that reflects only light of a specific wavelength and transmits light of other wavelengths, reflects the laser light that has passed through the shutter 24 toward the Z scanner 27, and guides from the guide light source 30. Transmit light as it is.

  The Z scanner 27 is a laser beam scanning mechanism including one or two or more lenses arranged on the optical path and a lens driving motor that moves the lens. By moving the lens, the Z scanner 27 moves from the head unit 4. The focal position of the emitted laser light is moved in the optical axis direction. The Z scanner 27 has a laser beam condensing function. The Z scanner 27 is a scanning mechanism capable of moving the focal position of the laser light in the optical axis direction following the height of the workpiece W.

  As the lens driving motor of the Z scanner 27, for example, a stepping motor or a voice coil motor that operates based on a pulse signal from the main control circuit 11 is used.

  The XY scanner 28 is a laser beam scanning mechanism composed of two mirrors respectively arranged on intersecting rotation axes and a mirror driving motor for rotating these mirrors, and rotates the mirror around the rotation axis. As a result, the laser beam is scanned in a direction crossing the optical axis. Here, the XY scanner 28 includes an X scanner composed of a galvano mirror 28b for X-direction scanning and its driving motor 28a, and a Y scanner composed of a galvano mirror 28d for Y-direction scanning and its driving motor 28c. Shall.

  As the mirror driving motor of the XY scanner 28, for example, a servo motor having a position sensor such as a rotary encoder and operating based on a high frequency signal from the XY scanner control circuit 31 is used.

  The laser beam that has passed through the Z scanner 27 is reflected by the galvanometer mirror of the XY scanner 28 and is irradiated onto the workpiece W. The guide light source 30 is a light source device that generates guide light for visualizing the irradiation position of the laser light on the workpiece W. The guide light emitted from the guide light source 30 passes through the dichroic mirror 26 and enters the optical path of the laser light. The guide light that has entered the optical path of the laser light is applied to the workpiece W via the Z scanner 27 and the XY scanner 28.

  The workpiece machining information storage unit 12 is a memory that holds information relating to laser machining of the workpiece W as workpiece machining information. As workpiece machining information, three-dimensional position information indicating an irradiation target of laser light and laser oscillation are controlled. Laser output control information and the like are held. For example, coordinate data is held as the three-dimensional position information. Further, as the laser output control information, for example, the peak power, pulse width, repetition frequency, and the like of the laser light are held.

  The peak power is a physical quantity obtained by dividing the pulse energy by the pulse width. The pulse width is the time length of the pulse wave at a power level that is about half of the peak power, and the repetition frequency is the frequency of pulse oscillation. The center wavelength is the wavelength of the laser beam generated by the laser beam amplifier 15.

  The main control circuit 11 is a control unit that controls the excitation light source 14, the laser light amplifier 15, and the Z scanner 27 based on the workpiece machining information held in the workpiece machining information storage unit 12. Specifically, based on the laser output control information, an oscillator control signal for adjusting the peak power and pulse width of the laser light emitted from the head unit 4 is generated and output to the excitation light source 14 and the laser light amplifier 15. Is performed.

  Also, based on the laser output control information and the three-dimensional position information, an operation of generating a pulse signal as a drive signal for controlling the lens driving motor of the Z scanner 27 and outputting it to the Z scanner 27 is performed. The power supply circuit 13 is a power supply device that supplies power to the excitation light source 14, the laser light amplifier 15, the drive motor in the head unit 4, and the like.

  The XY scanner control circuit 31 is a control unit that controls the XY scanner 28, and workpiece processing information transferred from the workpiece processing information storage unit 12 of the main body 2 via the main control circuit 11 and position information from the XY scanner 28. Based on the above, the XY scanner 28 is driven and controlled. Specifically, an operation of generating a high-frequency signal as a drive signal for controlling the mirror drive motor of the XY scanner 28 based on the three-dimensional position information and the position information of the servo motor and outputting it to the XY scanner 28 is performed. Done. That is, the XY scanner control circuit 31 performs feedback control based on the position information detected by the position sensor of the servo motor of the XY scanner 28 so that the servo motor correctly follows the input instruction position.

  The Z scanner 27 is less susceptible to noise because the responsiveness of the lens drive motor is slower than that of the XY scanner 28 due to the scanning characteristics of driving the lens drive motor to move the lens in the optical axis direction.

  As such a laser processing apparatus 100, for example, a laser marker that marks characters and figures on the surface of the workpiece W by irradiating laser light can be considered. Further, the three-dimensional position information and the laser output control information as the workpiece machining information are manually set based on the input information from the console 1 or automatically set. Alternatively, a PC (personal computer) can be connected to the laser processing apparatus 100, and workpiece processing information can be set using a mouse while viewing the PC monitor screen.

<Z-direction scan>
2 and 3 are explanatory views schematically showing an example of the scanning operation in the Z direction in the laser processing apparatus 100 of FIG. 1, in which the Z scanner 27 and the XY scanner 28 in the head unit 4 are shown. . FIG. 2 shows a state in which the focal position of the laser beam is moved away from the head unit 4 by shortening the distance Rd1 between the incident lens 27a and the emission lens 27b. Further, FIG. 3 shows how the focal position approaches the head unit 4 by increasing the distance Rd2 between the incident lens 27a and the outgoing lens 27b.

  The Z scanner 27 includes an incident lens 27a disposed on the dichroic mirror 26 side, an exit lens 27b disposed on the mirror 32 side, and a lens driving motor (not shown) that moves the incident lens 27a in the optical axis direction. Consists of. If the distance Rd1 between the entrance lens 27a and the exit lens 27b is shortened, the beam divergence angle is increased. Therefore, the focal position of the laser beam emitted from the head unit 4 in the optical axis direction is the exit surface of the laser beam. That is, the working distance Ld1 becomes longer as the distance from the opening surface provided in the underframe 33 of the head portion 4 increases.

  On the other hand, if the distance Rd2 (Rd2> Rd1) between the entrance lens 27a and the exit lens 27b is increased, the beam divergence angle is reduced. Therefore, the focal position of the laser light emitted from the head unit 4 in the optical axis direction is reduced. Approaches the exit surface, and the working distance Ld2 (Ld2 <Ld1) becomes shorter.

  In other words, the focal position can be moved away by moving the incident lens 27a closer to the outgoing lens 27b, and the focal position can be moved closer by moving the incident lens 27a away from the outgoing lens 27b. it can.

<Head>
FIG. 4 is a developed view schematically showing a configuration example of the head unit 4 of the laser processing apparatus 100 of FIG. 1, and shows the inside of the head unit 4 with the front cover and the rear cover removed. The head portion 4 is divided into three regions by an under frame 33, a rear frame 34, a front frame 35, and a center frame 36, and each device is accommodated in these regions.

  The under frame 33, the rear frame 34, the front frame 35, and the center frame 36 are all members made of a rectangular metal plate, for example, an aluminum plate, and the rear frame 34, the front frame 35, and the center frame 36 are all members. It is arranged in a standing state on the under frame 33.

  The optical fiber cable 3 is attached to the rear surface of the rear frame 34 via a cover portion 3a. The optical fiber cable 3 is attached so that its optical axis intersects the frame surface of the rear frame 34. The front frame 35 is disposed with its frame surface facing the frame surface of the rear frame 34. The center frame 36 connects these frames 34 and 35, and end faces facing each other are fixed to the frames 34 and 35, respectively. The rear frame 34 and the front frame 35 are both fixed on the under frame 33.

  Of the region between the front frame 35 and the rear frame 34, the region on the right side of the center frame 36 accommodates the optical isolator 21, the beam expander 22, and the X scanner control board 31a. The optical isolator 21 and the beam expander 22 are arranged with their optical axes aligned with the optical fiber cable 3. The X scanner control board 31 a is a wiring board on which a control circuit for controlling the X scanner is formed, and is arranged substantially parallel to the frame surface of the center frame 36. In FIG. 4, for convenience of explanation, the optical isolator 21 and the optical fiber cable 3 are illustrated separately, but the optical isolator 21 and the optical fiber cable 3 may be configured integrally.

  Of the area between the front frame 35 and the rear frame 34, the area on the left side of the center frame 36 accommodates the Y scanner control board 31c and the head control board 37. The XY scanner 28 includes an X scanner including a galvano mirror 28b for X-direction scanning and a driving motor 28a thereof, and a Y scanner including a galvano mirror 28d for Y-direction scanning and a driving motor 28c thereof. The Y scanner control board 31 c is a wiring board on which a control circuit for controlling the Y scanner is formed, and is arranged substantially parallel to the frame surface of the center frame 36. In this embodiment, the Y scanner control board 31c is accommodated in the left area of the center frame 36, and the X scanner control board 31a is accommodated in the right area, but the X scanner control board 31 is accommodated in the left area of the center frame 36. The Y scanner control board 31c may be accommodated in the right area 31a.

  In the area on the front side of the front frame 35, a Z scanner 27, a mirror 32, and the like are accommodated. The Z scanner 27 includes a movable lens arranged to be movable in the optical axis direction and a drive motor for adjusting the position of the movable lens, and the optical axis thereof is substantially parallel to the frame surface of the front frame 35. Are arranged as follows. The mirror 32 is arranged so that the optical axis of the laser beam that has passed through the Z scanner 27 is bent by approximately 90 degrees in the vertical plane.

  Laser light that has passed through the Z scanner 27 and reflected by the mirror 32 is incident on the galvano mirror 28b for X-direction scanning substantially parallel to the longitudinal direction of the optical isolator 21 and the optical axis direction of the beam expander 22. .

  As described above, the XY scanner 28 is disposed below the optical isolator 21 attached to the center frame 36 and in a region (space) in front of the X scanner control board 31a and the Y scanner control board 31c. . That is, the XY scanner 28 is disposed so as to be interposed between the Z scanner 27 and the X scanner control board 31a and the Y scanner control board 31c.

  5 to 7 are perspective views showing a configuration example of the head unit 4 of the laser processing apparatus 100 of FIG. 1, and show the inside of the head unit 4 with the rear cover removed. FIG. 5 illustrates a state in which the head unit 4 is viewed from the right front, and FIG. 6 illustrates a state in which the head unit 4 is viewed from the left front. FIG. 7 shows a state in which the head unit 4 is viewed from below.

  The head portion 4 has a rectangular parallelepiped box made up of a rear cover (not shown), a front cover 4a, an under frame 33, and a rear frame 34, which is divided into three regions by a front frame 35 and a center frame 36. Each device is housed in

  The rear frame 34 is a frame in which the optical fiber cable 3 is attached to the rear surface and the optical isolator 21 or the like is attached to the front surface. The optical fiber cable 3 is attached via the cover portion 3a so that the optical axis intersects the frame surface of the rear frame 34. The optical isolator 21 is arranged with the optical axis aligned with the optical fiber cable 3.

  The front frame 35 is a frame disposed to face the rear frame 34 with the optical isolator 21 and the beam expander 22 interposed therebetween. The center frame 36 is a frame that connects the rear frame 34 and the front frame 35, and is arranged so as to intersect the rear frame 34 and the front frame 35.

  The center frame 36 is disposed substantially parallel to the optical isolator 21 and the beam expander 22, and the frames 34 to 36 are disposed in an H shape when viewed from above. A region in front of the front frame 35 is covered with a front cover 4a, and accommodates a beam sampler 23, a shutter 24, a photo interrupter 25, a dichroic mirror 26, a Z scanner 27, a mirror 32, a power monitor 29, and a guide light source 30. Has been.

  An optical isolator 21, a beam expander 22, and an X scanner control board 31a are accommodated in a region on the right side of the center frame 36 between the front frame 35 and the rear frame 34. The optical isolator 21 and the beam expander 22 are arranged so that the optical axis is parallel to the center frame 36.

  On the other hand, a Y scanner control board 31 c and a head control board 37 are accommodated in the left region of the center frame 36 between the front frame 35 and the rear frame 34. That is, the X scanner control board 31a and the Y scanner control board 31c are arranged on the opposite sides with respect to the center frame 36.

  An X scanner composed of a galvano mirror 28b for X-direction scanning and its driving motor 28a, and a Y scanner composed of a galvano mirror 28d for Y-direction scanning and its driving motor 28c consist of the above-mentioned right region and the above-mentioned left region. It is housed across. Therefore, the center frame 36 is formed with a notch 36a (see FIG. 4) for accommodating the XY scanner 28. When a part of the XY scanner 28 enters the chipped portion 36a, the height of the head portion 4 can be reduced.

  The X scanner control board 31a is a wiring board on which a control circuit for controlling the X scanner is formed, and the Y scanner control board 31c is a wiring board on which a control circuit for controlling the Y scanner is formed. The X scanner control board 31a is provided with an operational amplifier 31b as an amplifier for supplying a drive current to a drive motor for the X scanner. The operational amplifier 31b is a flat plate-like component, is erected on the X scanner control board 31a, and is fixed with the heat radiating surface in close contact with the rear frame 34.

  On the other hand, the Y scanner control board 31c is provided with an operational amplifier 31d as an amplifier for supplying a drive current to a drive motor for the Y scanner. The operational amplifier 31d is also a flat plate-like component, is erected on the Y scanner control board 31c, and is fixed with the heat radiating surface in close contact with the rear frame 34. The operational amplifiers 31b and 31d disposed on the scanner control boards 31a and 31c are brought into close contact with the rear frame 34 to improve heat dissipation.

  The head control board 37 is a wiring board on which a control circuit for controlling the shutter 24, the photo interrupter 25, the power monitor 29, the guide light source 30, and various indicators (not shown) is formed.

  Here, the X scanner control board 31a, the Y scanner control board 31c, and the head control board 37 are all substantially parallel to the center frame 36 in order to reduce the thickness of the head portion 4 in the direction intersecting the center frame 36. Is arranged. The X scanner control board 31 a is attached to the right side of the center frame 36, and the Y scanner control board 31 c and the head control board 37 are attached to the left side of the center frame 36. In this example, the X scanner control board 31a, the Y scanner control board 31c, and the head control board 37 are all multistage boards in which control circuits are distributed on a plurality of boards arranged to face each other. .

  An opening 33a for emitting laser light scanned by the XY scanner 28 is formed in the under frame 33 constituting the bottom surface of the head unit 4, and a cover lens is disposed. The laser beam reflected by the dichroic mirror 26 passes through the Z scanner 27 and then is reflected by the X-direction scanning galvanometer mirror 28b. Then, the light is reflected by the Y-scanning galvanometer mirror 28d and irradiated onto the workpiece W through the opening 33a.

  8 and 9 are perspective views showing a configuration example of the head unit 4 of the laser processing apparatus 100 of FIG. 1, and shows a state in which the head unit 4 with the rear cover and the front cover 4a removed is viewed from the left front. Has been. FIG. 8 shows each device in a region in front of the front frame 35, and FIG. 9 shows a cut surface around the drive mechanism 24b of the shutter 24.

  In the front region of the front frame 35, a power monitor 29, a power monitor amplifier 29a, a blocking plate 24a of the shutter 24, a driving mechanism 24b thereof, a dust fall prevention cover 24c, a photo interrupter 25, a Z scanner 27, and the like are arranged. Yes.

  The laser light transmitted through the optical fiber cable 3 passes through the optical isolator 21 and the beam expander 22, and then is reflected by the beam sampler 23 toward the dichroic mirror 26 and the other part is transmitted. Then, it enters the power monitor 29.

  The optical isolator 21 and the beam expander 22 are arranged so that their optical axes coincide with each other, and a part of the laser light after passing through the beam expander 22 advances straight and enters the power monitor 29. On the other hand, another part of the laser light after passing through the beam expander 22 is reflected by the beam sampler 23 and enters the dichroic mirror 26 through the blocking plate 24a.

  The power monitor 29 is disposed on the opposite side of the front frame 35 from the optical isolator 21 and the beam expander 22. The light receiving surface of the power monitor 29 is disposed so as to face the exit side end surface of the beam expander 22 via the front frame 35.

  The Z scanner 27 is arranged on the opposite side of the front frame 35 from the optical isolator 21 and the beam expander 22 so that the optical axis is substantially parallel to the front frame 35. On the other hand, the XY scanner 28 is disposed between the rear frame 34 and the front frame 35, and the laser light that has passed through the Z scanner 27 is incident substantially parallel to the optical isolator 21 and the beam expander 22.

  The shutter 24 includes a blocking plate 24a for blocking laser light, a drive mechanism 24b for rotating the blocking plate 24a, and a dust fall prevention cover 24c for preventing dust from being scattered around. As the drive mechanism 24b, for example, a rotary solenoid that converts a magnetic force in the rotation axis direction into a rotation torque is used. The dust fall prevention cover 24c is a cover that covers the sliding part of the rotary solenoid and the blocking plate 24a of the drive mechanism 24b.

  10 and 11 are perspective views showing a configuration example of the head unit 4 of the laser processing apparatus 100 of FIG. 1, and show the optical path of the laser light around the dichroic mirror 26. FIG. 10 shows a state where the head unit 4 is viewed from the left front, and FIG. 11 illustrates a state where the head unit 4 is viewed from above.

  A beam sampler 23, a power monitor 29, a blocking plate 24a, a drive mechanism 24b, a dust drop prevention cover 24c, a dichroic mirror 26, a guide light source 30, a Z scanner 27, and the like are disposed in a front region of the front frame 35.

  The laser light transmitted via the optical fiber cable 3 passes through the optical isolator 21 and the beam expander 22, and then is reflected by the beam sampler 23, and the optical axis is bent at a right angle in the horizontal plane. The laser light then enters the dichroic mirror 26 via the blocking plate 24a and is reflected downward in the vertical plane.

  The laser light reflected by the dichroic mirror 26 passes through the Z scanner 27, is reflected by the mirror 32, and is incident on the XY scanner 28 from the horizontal direction with the optical axis bent at a right angle in the vertical plane. On the other hand, the guide light emitted from the guide light source 30 passes through the dichroic mirror 26 as it is and enters the optical path of the laser light.

  The guide light source 30 must be disposed on the downstream side of the blocking plate 24a of the shutter 24 so that the guide light can be irradiated even when the laser beam is blocked. Therefore, the beam sampler 23 and the dichroic mirror 26 are arranged in a horizontal plane, the shutter 24 is arranged between the beam sampler 23 and the dichroic mirror 26, and the guide light source 30 is arranged directly above the dichroic mirror 26. . The Z scanner 27 is disposed directly below the dichroic mirror 26 with the optical axis directed downward.

  Since the power monitor 29 is disposed on the opposite side of the front frame 35 from the optical isolator 21 and the beam expander 22, these frames are compared with the case where the power monitor 29 is disposed between the rear frame 34 and the front frame 35. Since the distance between them is short, the length of the head part 4 can be shortened. In particular, since the laser light that has passed through the optical isolator 21 and the beam expander 22 is received by the power monitor 29 as it is, when the laser light after passing through the beam expander 22 is reflected by a mirror and then received by the power monitor 29, That is, the length of the head unit 4 is equivalent to the size of the light receiving surface of the power monitor 29 as compared with the case where the power monitor 29 is arranged so that the light receiving surface is parallel to the frame surface of the center frame 36. Can be shortened.

  Further, since the Z scanner 27 is arranged with the optical axis facing downward, the thickness of the head portion 4 in the left-right direction can be reduced. Further, since the dust fall prevention cover 24 c is provided, it is possible to prevent the metal powder generated inside the shutter 24 from dropping and adhering to the optical system such as the Z scanner 27.

  According to the present embodiment, since the main control circuit 11 that controls the Z scanner 27 is provided in the main body 2, it is possible to reduce the size of the head 4 compared to the case where it is provided in the head 4. . Further, since the XY scanner control circuit 31 for controlling the XY scanner 28 is provided in the head unit 4, it is possible to suppress the addition of noise to the drive signal for controlling the XY scanner. Furthermore, since a control circuit for the Z scanner 27 is provided in the main body 2, heat generation in the head 4 can be suppressed.

  In addition, since the X scanner control board 31a and the Y scanner control board 31c are arranged substantially in parallel with the center frame 36, the head unit 4 can be thinned in the direction intersecting the center frame 36. Further, when the XY scanner control circuit 31 is allocated to the X scanner control board 31a and the Y scanner control board 31c, the X direction scanning control circuit and the Y direction scanning control circuit are provided on one board. In comparison, the size of the substrate can be reduced. Further, since the X scanner control board 31a and the Y scanner control board 31c are arranged on the opposite sides with respect to the center frame 36, the operational amplifiers 31b and 31d can be separated from each other.

DESCRIPTION OF SYMBOLS 1 Console 2 Main body part 3 Optical fiber cable 3a Cover part 4 Head part 4a Front cover 11 Main control circuit 12 Work processing information storage part 13 Power supply circuit 14 Excitation light source 15 Laser light amplifier 21 Optical isolator 22 Beam expander 23 Beam sampler 24 Shutter 24a Blocking plate 24b Drive mechanism 24c Dust fall prevention cover 25 Photo interrupter 26 Dichroic mirror 27 Z scanner 28 XY scanner 28a, 28c Driving motor 28b, 28d Galvano mirror 29 Power monitor 29a Power monitor amplifier 30 Guide light source 31 XY scanner control circuit 31a X-scanner control board 31b X-scanner operational amplifier 31c Y-scanner control board 31d Y-scanner operational amplifier 32 Mirror 33 Underframe 33a Opening 34 Rear frame 35 Front frame 36 Center frame 36a Notch 37 Head control board 100 Laser processing apparatus W Workpiece

Claims (5)

A main body having laser light amplification means for amplifying laser light using an optical fiber having a laser medium added to the core;
A head unit that scans the laser beam transmitted from the main body unit via an optical fiber cable,
The head unit includes a Z scanner capable of adjusting a focal position of the laser beam in the optical axis direction;
An XY scanner that scans the laser beam in a direction crossing the optical axis;
XY scanner control means for controlling the XY scanner,
The laser processing apparatus, wherein the main body has Z scanner control means for controlling the Z scanner. The head portion includes a first frame to which the optical fiber cable is attached such that the optical axis intersects the frame surface;
A return light suppression means for passing the laser light emitted from the end face of the optical fiber cable and suppressing the return light;
A second frame having a frame surface opposed to the frame surface of the first frame with the return light suppressing means interposed therebetween;
A third frame connecting the first frame and the second frame, the frame surface being arranged substantially parallel to the longitudinal direction of the return light suppression means,
The XY scanner control means includes an X scanner control board provided with a control circuit for X-direction scanning, and a Y scanner control board provided with a control circuit for Y-direction scanning. The laser processing apparatus according to claim 1, wherein the Y scanner control board is disposed substantially parallel to the frame surface of the third frame. The Z scanner is disposed on the side opposite to the return light suppression means with respect to the second frame so that the optical axis is substantially parallel to the frame surface of the second frame;
3. The XY scanner is disposed between a first frame and a second frame, and the laser light that has passed through the Z scanner is incident substantially in parallel with a longitudinal direction of the return light suppressing means. The laser processing apparatus as described in.   The laser processing apparatus according to claim 2, wherein the X scanner control board is disposed on the opposite side of the Y scanner control board with respect to the third frame.   3. The power monitor that receives the laser light that has passed through the return light suppression means and detects laser power is disposed on the opposite side of the return light suppression means with respect to the second frame. The laser processing apparatus as described.

Images