Laser processing apparatus

Abstract

A laser processing apparatus 3 includes: a laser head H; a conveying device 4 that conveys a workpiece W; a head driving mechanism that moves the laser head H; a dust collecting box 60 that moves below the workpiece W and follows the laser head H such that the dust collecting box 60 is disposed below the laser head H; an outer support roller 81 and an inner support roller 82 that are provided at an opening 61 of the dust collecting boz 60 and are rotatable around an axis parallel to a width direction orthogonal to a conveying direction Fy; and a counter roller 9 that rotates the outer support roller 81 in synchronization with a conveying operation of the workpiece W by the conveying device 4. The counter roller 9 transmits motive power of the conveying device 4 as a belt conveyor to the outer support roller 81.

Claims

1. A laser processing apparatus comprising: a laser irradiation unit; a conveying device that conveys a plate material along a conveying direction; a drive unit that moves the laser irradiation unit above the plate material; a dust collecting unit that moves below the plate material and follows the laser irradiation unit such that the dust collecting unit is disposed directly below the laser irradiation unit; and a roller that is provided at an opening of the dust collecting unit and is rotatable around an axis parallel to a width direction orthogonal or substantially orthogonal to the conveying direction, wherein the laser processing apparatus further comprising a driving mechanism that rotates the roller in synchronization with a conveying operation of the plate material by the conveying device, a non-contact support portion is provided at the opening, and the non-contact support portion suctions a lower surface of the plate material toward a suction surface and supports the plate material without bringing the lower surface of the plate material and the suction surface into contact with each other, the opening includes an upstream-side opening edge extending along the width direction, and a downstream-side opening edge extending along the width direction on a downstream side of the upstream-side opening edge in the conveying direction in a plan view, and the roller includes a plurality of rollers, and the non-contact support portion includes a plurality of non-contact support portions, and one or more of the rollers and one or more of the non-contact support portions are provided alternately along the width direction at each of the upstream-side opening edge and the downstream-side opening edge.

2. The laser processing apparatus according to claim 1, wherein the conveying device comprises a belt conveyor, and the driving mechanism comprises a power transmission mechanism that transmits motive power of the belt conveyor to the roller.

3. The laser processing apparatus according to claim 2, wherein the belt conveyor includes a plurality of belt rollers that are rotatable around the axis parallel to the width direction, and a strip-shaped belt stretched over the plurality of belt rollers, and the power transmission mechanism comprises a counter roller that is rotatable around the axis parallel to the width direction, and an outer peripheral surface of the counter roller is in contact with the belt roller or the belt and the roller.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

(1) FIG. 1 is a diagram showing the configuration of a laser processing system according to an embodiment of the present invention;

(2) FIG. 2 is a perspective view showing a schematic configuration of a laser processing apparatus;

(3) FIG. 3 is a plan view of a dust collecting box from a workpiece side;

(4) FIG. 4 is a cross-sectional view taken along the line IV-IV intersecting the pair of support rollers in FIG. 3;

(5) FIG. 5 is a cross-sectional view taken along the line V-V intersecting the non-contact support pad in FIG. 3;

(6) FIG. 6A is a perspective view of the non-contact support pad from a suction surface side;

(7) FIG. 6B is a cross-sectional view of a non-contact support pad 7 along the line VI-VI in FIG. 6A;

(8) FIG. 7 is an enlarged view of an upstream-side opening edge and an upstream cover of FIG. 5; and

(9) FIG. 8 is a view of a lower surface of the upstream cover seen from a side of the non-contact support pad.

DETAILED DESCRIPTION OF THE INVENTION

(10) Hereinafter, a laser processing apparatus 3 according to an embodiment of the present invention will be described with reference to the drawings.

(11) FIG. 1 is a diagram showing a configuration of a laser processing system 1. The laser processing system 1 includes a leveler device 2 that removes waviness of a workpiece W which is a plate material fed from a roll-shaped coil material C and linearly straightens the workpiece W, and a laser processing apparatus 3 for cutting the workpiece W linearly straightened by the leveler device 2 with a laser beam. The workpiece W is, for example, a plate material made of an aluminum alloy or a steel plate; however, the present invention is not intended to be limited thereto.

(12) The leveler device 2 includes a plurality of upper rollers 21 provided on the upper side in the vertical direction with respect to the workpiece W to be fed from the coil material C (in the example of FIG. 1, three pieces), and a plurality of lower rollers 22 provided across the workpiece W with respect to these upper rollers 21 (in the example of FIG. 1, four pieces). The rotation axes of the upper rollers 21 and the rotation axes of the lower rollers 22 are provided parallel to one another. These lower rollers 22 and upper rollers 21 are provided alternately along the feeding direction of the workpiece W. The leveler device 2 extends the workpiece W fed from the coil material C to be flat by the plurality of upper rollers 21 and the plurality of lower rollers 22, thereby removing the waviness of the plate material and linearly straightening the workpiece W. The workpiece W straightened linearly by the leveler device 2 is fed to the laser processing apparatus 3.

(13) FIG. 2 is a perspective view showing a schematic configuration of a laser processing apparatus 3. The laser processing apparatus 3 includes a conveying device 4 for conveying the workpiece W along a conveying direction Fy, a laser head H for generating a laser beam and irradiating the workpiece W with the laser beam, a head driving mechanism 5 for moving the laser head H above the workpiece W fed along the conveying direction Fy, and a dust collector 6 for collecting a spatter caused by irradiating the workpiece W with the laser beam.

(14) The conveying device 4 is a belt conveyor, and includes a plurality of belt rollers 41, 42, 43, and 44 which are rotatable about an axis parallel to a width direction Fx orthogonal to the conveying direction Fy (only four rollers are illustrated in FIG. 2), an endless strip-shaped belt 45 stretched over these belt rollers 41 to 44, and a roller driving device (not shown) for feeding the belt 45 to the downstream side along the conveying direction Fy by rotating any of the plurality of belt rollers 41 to 44 (for example, the first belt roller 41).

(15) The first to fourth belt rollers 41 to 44 are provided in this order from the upstream side to the downstream side along the conveying direction Fy. Between the second belt roller 42 and the third belt roller 43, a dust collecting box 60 to be described later is provided. Furthermore, the belt 45 is stretched over the first to fourth belt rollers 41 to 44 so as to avoid the dust collecting box 60. Furthermore, the second belt roller 42 and the third belt roller 43 are slidable to the downstream side or to the upstream side along the conveying direction Fy together with the dust collecting box 60 by a box driving mechanism to be described later.

(16) The head driving mechanism 5 includes an X-axis rail 51 extending along the width direction Fx above the belt 45, and a Y-axis rail 52 extending along the conveying direction Fy at the side portion of the belt 45. The X-axis rail 51 slidably supports the laser head H along its extending direction (i.e., the width direction Fx). The Y-axis rail 52 slidably supports the X-axis rail 51 along its extending direction (i.e., the conveying direction Fy). This allows the head driving mechanism 5 to move the laser head H along the conveying direction Fy and the width direction Fx above the workpiece W conveyed by the conveying device 4.

(17) The dust collector 6 includes a box-shaped dust collecting box 60 extending along the width direction Fx, and a box driving mechanism (not shown) for moving the dust collecting box 60 along the conveying direction Fy.

(18) The dust collecting box 60 is provided between the second belt roller 42 and the third belt roller 43 below the workpiece W. A rectangular opening 61 extending along the width direction Fx in a plan view is provided above the dust collecting box 60. The spatter caused by irradiating the workpiece W with a laser beam from the laser head H is collected in the dust collecting box 60 through the opening 61. The spatter collected in the dust collecting box 60 is appropriately discharged from a discharge unit 63 provided on a side cover 62.

(19) The box driving mechanism moves the dust collecting box 60, the second belt roller 42, and the third belt roller 43 to follow the movement of the laser head H along the conveying direction Fy, such that the opening 61 of the dust collecting box 60 is disposed directly below the laser head H.

(20) FIG. 3 is a plan view of the dust collecting box 60 from the workpiece W side. As shown in FIG. 3, in a plan view, the opening 61 of the dust collecting box 60 has a rectangular shape, and includes an upstream-side opening edge 64 extending along the width direction Fx, and a downstream-side opening edge 65 extending along the width direction Fx on the downstream side of the upstream-side opening edge 64 in the conveying direction Fy.

(21) The upstream-side opening edge 64 includes a plurality of disk-shaped non-contact support pads 7 (in the example of FIG. 3, seven pieces) in a plan view, the plurality of support rollers pairs 8 (in the example of FIG. 3, six sets) made by a pair of an outer support roller 81 and an inner support roller 82, and a rectangular upstream cover 66 extending along the width direction Fx in a plan view.

(22) In the upstream-side opening edge 64, one non-contact support pad 7 and the pair of the support rollers 8 are provided in rows and alternately along the width direction Fx. It should be noted that FIG. 3 shows a case in which one non-contact support pad 7 and the pair of the support rollers 8 are provided alternately along the width direction Fx in the upstream-side opening edge 64; however, the present invention is not intended to be limited thereto. Two or more of the non-contact support pads 7 and two or more sets of the support roller pairs 8 may be provided alternately along the width direction Fx in the upstream side opening edge 64.

(23) The downstream-side opening edge 65 includes a plurality of disk-shaped non-contact support pads 7 (in the example of FIG. 3, seven pieces) in a plan view, a plurality of the pairs of the support rollers 8 (in the example of FIG. 3, six sets), and a rectangular downstream cover 67 extending along the width direction Fx in a plan view.

(24) In the downstream-side opening edge 65, one non-contact support pad 7 and a pair of the support rollers 8 are provided in rows and alternately along the width direction Fx. It should be noted that FIG. 3 shows a case in which one non-contact support pad 7 and the pair of the support rollers 8 are provided alternately along the width direction Fx in the downstream-side opening edge 65; however, the present invention is not intended to be limited thereto. Two or more of the non-contact support pads 7 and two or more sets of the support rollers 8 may be provided alternately along the width direction Fx in the downstream-side opening edge 65.

(25) FIG. 4 is a cross-sectional view taken along a line IV-IV intersecting the pair of the support rollers 8 in FIG. 3. The dust collecting box 60 is substantially U-shaped in cross-sectional view. At the upstream-side opening edge 64 of the dust collecting box 60, the outer support roller 81 and the inner support roller 82 that are each rotatable about the axis parallel to the width direction Fx (see FIG. 3) are provided in parallel in this order along the conveying direction Fy from the upstream side to the downstream side. Furthermore, at the downstream-side opening edge 65 of the dust collecting box 60, the inner support roller 82 and the outer support roller 81 that are each rotatable about the axis parallel to the width direction Fx are provided in parallel in this order along the conveying direction Fy from the upstream side to the downstream side.

(26) At the upstream cover 66, a plurality of upstream-side roller windows 66a which are each a substantially rectangular opening in a plan view are provided at predetermined intervals along the width direction Fx (in the example of FIG. 3, six pieces). Furthermore, as shown in FIG. 4, a portion of the outer peripheral surface of the total of six sets of the outer support rollers 81 and the inner support rollers 82 provided at the upstream-side opening edge 64 is exposed to the side of the workpiece W through these upstream-side roller windows 66a. In other words, a portion of the outer peripheral surface of the outer support rollers 81 and the inner support rollers 82 protrudes from the upper surface of the upstream cover 66 to the side of the workpiece W. Therefore, the lower surface of the workpiece W conveyed along the conveying direction Fy by the conveying device 4 is brought into contact with the outer peripheral surfaces of these outer support rollers 81 and the inner support rollers 82. Furthermore, as shown in FIGS. 3 and 4, the end of the upstream side and the end of the downstream side along the conveying direction Fy of the upstream cover 66 are slightly bent downwards in the vertical direction, respectively. Therefore, the peripheries of the plurality of sets of the outer support rollers 81 and the inner support rollers 82 provided on the upstream side opening edge 64 are covered by the upstream cover 66.

(27) Furthermore, as shown in FIG. 4, a counter roller 9 which is rotatable about the axis parallel to the outer support roller 61 is provided between the outer support roller 81 of the upstream-side opening edge 64 and the second belt roller 42. The outer peripheral surface of the counter roller 9 is in contact with the belt 45 and the outer support roller 81. Therefore, a part of the power for conveying the workpiece W along the conveying direction Fy in the conveying device 4 as a belt conveyor is transmitted to the outer support roller 81 via the counter roller 9. This allows the outer support roller 81 to rotate in synchronization with the conveying operation of the workpiece W by the conveying device 4. It should be noted that FIG. 4 illustrates a case in which the outer peripheral surface of the counter roller 9 is in contact with the belt 45; however, the present invention is not intended to be limited thereto. The outer peripheral surface of the counter roller 9 may be in contact with the outer peripheral surface of the second belt roller 42.

(28) At the downstream cover 67, a plurality of downstream-side roller windows 67a, which are each a substantially rectangular opening in a plan view, are provided at predetermined intervals along the width direction Fx (in the example of FIG. 3, six pieces). Furthermore, as shown in FIG. 4, a portion of the outer peripheral surface of the total 6 sets of the outer support rollers 81 and the inner support rollers 82 provided at the downstream-side opening edge 65 is exposed to the side of the workpiece W through these downstream side roller windows 67a. In other words, a portion of the outer peripheral surface of the outer support roller 81 and the inner support roller 82 protrudes from the upper surface of the downstream cover 67 to the side of the workpiece W. Therefore, the lower surface of the workpiece W conveyed along the conveying direction Fy by the conveying device 4 is brought into contact with the outer peripheral surfaces of these outer support roller 81 and the inner support roller 82. Furthermore, as shown in FIGS. 3 and 4, the end of the upstream side and the end of the downstream side along the conveying direction Fy of the downstream cover 67 are slightly bent down in the vertical direction, respectively. Therefore, the peripheries of the plurality of sets of the outer support rollers 81 and the inner support roller 82 provided at the downstream-side opening edge 65 are covered by the downstream cover 67.

(29) Furthermore, as shown in FIG. 4, the counter roller 9 which is rotatable about the axis parallel to the outer support roller 81 is provided between the outer support roller 81 of the downstream-side opening edge 65 and the third belt roller 43. The outer peripheral surface of the counter roller 9 is in contact with the belt 45 and the outer support roller 81. Therefore, a portion of the power for conveying the workpiece W along the conveying direction Fy in the conveying device 4 as a belt conveyor is transmitted to the outer support roller 81 via the counter roller 9. This allows the outer support roller 81 to rotate in synchronization with the conveying operation of the workpiece W by the conveying device 4. It should be noted that FIG. 4 illustrates a case in which the outer peripheral surface of the counter roller 9 is in contact with the belt 45; however, the present invention is not intended to be limited thereto. The outer peripheral surface of the counter roller 9 may be in contact with the outer peripheral surface of the third belt roller 43.

(30) FIG. 5 is a cross-sectional view taken along the line V-V intersecting the non-contact support pad 7 in FIG. 3. The disk-shaped non-contact support pad 7 in a plan view is respectively provided at the upstream-side opening edge 64 and the downstream-side opening edge 65 of the dust collecting box 60.

(31) FIG. 6A is a perspective view of the non-contact support pad 7 from a side of a suction surface 71. FIG. 6B is a cross-sectional view of the non-contact support pad 7 along the line VI-VI in FIG. 6A.

(32) The non-contact support pad 7 has a cylindrical shape. An annular groove 73 in a plan view is provided at an outer peripheral edge 72 of the suction surface 71 of the non-contact support pad 7. A plurality of nozzle holes 74 (in the example of FIG. 6A, four) are provided in the groove 73. An air supply hole 76 to which an air pump (not shown) is connected is provided at substantially the center of the bottom surface 75 opposite to the suction surface 71 of the non-contact support pad 7. Furthermore, as shown in FIG. 6B, an air flow path 77 for communicating the air supply hole 76 and the plurality of nozzle holes 74 is provided inside the non-contact support pad 7.

(33) Therefore, in the non-contact support pad 7, when supplying air compressed by the air pump to the air supply hole 76, the swirling flow of air extending radially outward as indicated by a broken line arrow in FIG. 6A is generated from the plurality of nozzle holes 74 provided in the groove 73 of the suction surface 71. Therefore, when the workpiece W exists on the side of the suction surface 71, a negative pressure is generated between the suction surface 71 and the workpiece W by the Bernoulli effect, and the workpiece W is sucked toward the suction surface 71 by the negative pressure. As described above, the non-contact support pad 7 utilizes the negative pressure generated between the lower surface of the workpiece W and the suction surface 71 when the swirling flow of air from the nozzle hole 74 is ejected, thereby suctioning the lower surface of the workpiece W toward the suction surface 71, and supporting the workpiece W without bringing the lower surface of the workpiece W and the suction surface 71 into contact with each other.

(34) FIG. 7 is an enlarged view of the upstream-side opening edge 64 and the upstream cover 66 of FIG. 5. It should be noted that the configurations of the downstream-side opening edge 65 and the downstream cover 67 are substantially the same as in FIG. 4, and thus, illustration and a detailed description thereof will be omitted.

(35) As shown in FIG. 7, the peripheries of the plurality of non-contact support pads 7 provided at the upstream-side opening edge 64 are covered by the upstream cover 66. Furthermore, at the upstream cover 66, a plurality of upstream-side support pad windows 66b (in the example of FIG. 3, seven), which are each a disk-shaped opening in a plan view, is provided at predetermined intervals along the width direction Fx. The suction surface 71 of the plurality of non-contact support pads 7 provided at the upstream-side opening edge 64 is visible through the upstream-side support pad window 66b from the side of the workpiece W. The inner diameter of these upstream-side support pad windows 66b is slightly smaller than the outer diameter of the non-contact support pad 7. Therefore, the upstream cover 66 covers a portion of the outer peripheral edge 72 of the non-contact support pad 7.

(36) As described above, the portion of the outer peripheral surface of the outer support roller 81 and the inner support roller 82 protrudes from the upper surface of the upstream cover 66 to the side of the workpiece W, while the suction surface 71 of the non-contact support pad 7 is buried from the upper surface of the upstream cover 66. As shown in FIG. 7, a gap 69 is provided between the outer peripheral edge 72 of the non-contact support pad 7 and the lower surface of the upstream cover 66.

(37) FIG. 8 is a view of the lower surface of the upstream cover 66 seen from the side of the non-contact support pad 7. As shown in FIG. 8, a plurality of grooves 66c extending radially about the suction surface of the non-contact support pad 7 are provided at the peripheral edge of the upstream-side support pad window 66b of the lower surface of the upstream cover 66.

(38) Next, a description will be given of a procedure for cutting the workpiece W by the laser head H while removing the waviness of the workpiece W in the laser processing apparatus 3 as described above. First, when supplying compressed air to the air supply hole 76 of the non-contact support pad 7, the swirling flow of air extending radially outward from the nozzle hole 74 provided in the suction surface 71 is generated. As shown schematically by a broken line arrow in FIG. 7, the swirling flow of air flows into the gap 69 (refer to FIG. 7) provided between the lower surface of the workpiece W and the upper surface of the upstream cover 66 (or the downstream cover 67), and between the outer peripheral edge 72 of the non-contact support pad 7 and the upstream cover 66 (or the downstream cover 67), a result of which the negative pressure is generated between the suction surface 71 and the lower surface of the workpiece W. Furthermore, when the negative pressure is generated between the suction surface 71 and the lower surface of the workpiece W, the lower surface of the workpiece W is sucked toward the suction surface 71, following which the lower surface of the workpiece W is pressed against the outer peripheral surfaces of the outer support roller 81 and the inner support roller 82, a result of which the waviness of the workpiece W is removed. Therefore, with the laser processing apparatus 3, by irradiating a laser beam from the laser head H while removing the waviness of the workpiece W using the non-contact support pad 7 as described above, it is possible to cut the workpiece W with high accuracy.

(39) The laser processing apparatus 3 according to the present embodiment has the following effects.

(40) (1) The laser processing apparatus 3 includes: the conveying device 4 that conveys the workpiece W; the head driving mechanism 5 that moves the laser head H above the workpiece W; the dust collecting box 60 that moves below the workpiece W and follows the laser head H such that the dust collecting box 60 is disposed directly below the laser head H, and the outer support roller 81 and the inner support roller 82 that are provided at the opening 61 of the dust collecting box 60 and is rotatable around an axis parallel to the width direction Fx. With such a configuration, when moving the dust collecting box 60 along the conveying direction Fy, the support rollers 81 and 82 support the workpiece W while rolling on the lower surface of the workpiece W. Therefore, it is possible to prevent the damage on the lower surface of the workpiece W. Furthermore, the laser processing apparatus 3 further includes the counter roller 9 that rotates the outer support roller 81 in synchronization with a conveying operation of the workpiece W by the conveying device 4. With such a configuration, even when reversing the moving direction of the dust collecting box 60 while conveying the workpiece W along the conveying direction Fy by the conveying device 4, the outer support roller 81 no longer keeps rolling due to inertia in the original moving direction. Therefore, it is possible to prevent dislocation of the workpiece W in contact with the outer support roller 81. With such a configuration, it is possible to perform cutting processing with a laser beam irradiated from the laser head H with good precision.

(41) (2) In the laser processing apparatus 3, a belt conveyor is used as the conveying device 4 conveying the workpiece W, and the counter roller 9 transmits motive power of the belt conveyor to the outer support roller 61. With such a configuration, it is possible to rotate the outer support roller 81 in synchronization with the conveying operation of the workpiece W without adding any actuator for driving the outer support roller 81.

(42) (3) In the laser processing apparatus 3, the counter roller 9 that is rotatable around the axis parallel to the width direction Fx, and of which an outer peripheral surface is in contact with the belt rollers 41 to 44 or the belt 45 and the outer support rollers 81 transmits the motive power of the belt conveyor to the outer support roller 81. With such a configuration, it is possible to prevent the dislocation of the workpiece W when reversing the moving direction of the dust collecting box 60 with a simple configuration.

(43) (4) In the laser processing apparatus 3, one or more of the support rollers 81 and 82 and one or more of the non-contact support pads 7 are provided alternately along the width direction Fx at each of the upstream-side opening edge 64 and the downstream-side opening edge 65 of the dust collecting box 60. When the plurality of non-contact support pads 7 are provided at both the upstream-side opening edge 64 and the downstream-side opening edge 65 of the dust collecting box 60 as described above, the lower surface of the workpiece W is pressed against the outer peripheral surfaces of the support rollers 81 and 82. Therefore, while the waviness of the portion of the workpiece W to which the laser beam is irradiated is removed, the dislocation of the workpiece W when reversing the moving direction of the dust collecting box 60 becomes significant. In this regard, in the laser processing apparatus 3, the counter roller 9 causes the outer support roller 81 to rotate in synchronization with the conveying operation of the plate material by the conveying device 4 as described above. With such a configuration, it is possible to prevent dislocation of the workpiece W when reversing the moving direction of the dust collecting box 60 while removing the waviness of the workpiece W. Therefore, according to the laser processing apparatus 3, it is possible to quickly move the laser head H and the dust collecting box 60 while conveying the workpiece W.

(44) While an embodiment of the present invention has been described above, the present invention is not intended to be limited thereto. Within the spirit of the present invention, the configuration of detailed parts may be changed as appropriate.

(45) For example, in the above embodiment, the case has been described in which the counter roller 9 is used as a power transmission mechanism for transmitting the power of the conveying device 4 as a belt conveyor to the upstream-side support roller 81; however, the present invention is not limited thereto. The power transmission mechanism is not limited to the counter roller 9, and may be configured by combining components such as a shaft and a belt.

(46) Furthermore, for example, in the above embodiment, the case has been described in which the counter roller 9 is used as a driving mechanism for rotating the upstream-side support roller 81 in synchronization with the conveying operation of the workpiece W by the conveying device 4; however, the present invention is not limited thereto. For example, an actuator for rotating the upstream-side support roller 81 may be provided to drive this actuator in synchronization with the conveying operation by the conveying device 4, thereby rotating the upstream-side support roller 81 in synchronization with the conveying operation of the workpiece W by the conveying device 4.