Laser processing apparatus with debris removal system and integrated beam dump and method of operating same

Abstract

A laser processing apparatus is disclosed. In one embodiment, the laser processing apparatus includes a debris removal system having an integrated beam dump system capable of selectively positioning an absorber within the beam path of a laser energy beam. The beam dump system allows the laser energy beam to propagate through a scan lens of the laser processing apparatus but may prevent the laser energy beam from processing a workpiece. The beam dump system may include an actuator assembly capable of degenerating the absorber from the beam path to allow the beam to propagate to the workpiece and allowing debris from the laser processing to be sucked into a vacuum nozzle to prevent damage to the scan lens. The beam dump system may further include a heat transfer system capable of controlling the rate of heat escape from the absorber.

Description

CROSS-REFERENCE TO RELATED APPLICATIONS

[0001] This application claims the benefit of U.S. Provisional Patent Application No. 63 / 113,378, filed November 13, 2020, the contents of which are incorporated herein by reference in their entirety. [Technical Field]

[0002] The embodiments described herein generally relate to laser processing devices and their components and methods of operating the same.

[0003] Generally, laser processing devices can be used to process workpieces by directing a beam of laser energy onto the workpiece. In some applications, the laser processing device must be able to place a laser spot on the workpiece with high precision, which is dependent on maintaining critical tolerances and process parameters during operation.

[0004] Thermal stability of the laser beam path can be a critical factor in laser processing systems. In particular, thermal stability of transmissive beam path optics (e.g., beam expanders, beam shapers, wavefront compensation optics, relay optics, and beam delivery optics) enables high-precision laser spot placement and process invariance. To achieve high-precision operation, laser processing machines may measure and calibrate laser beam parameters (e.g., spot size, focal position, etc.) and laser spot position (e.g., measured position relative to predicted position) using beam characterization tools (e.g., beam profilers, power meters, beam position detectors, etc.) located optically downstream of the beam delivery optics (e.g., near the workpiece). The results of these measurements or calibrations may be used to calculate corrections to predicted beam placement or to compensate for suboptimal beam characteristics.

[0005] When a laser processing machine is processing a workpiece (and during beam characterization), the beam passes through all of the beam path optics, and the temperature of the beam delivery optics (e.g., the scan lens) may reach a steady state. During periods when the machine is not being characterized or processing a workpiece (e.g., during system idle, workpiece loading or unloading, workpiece inspection, etc.), the beam may be blocked (e.g., by a laser shutter, modulator, or beam dump located optically upstream of the scan lens) before reaching the scan lens. During these periods, the scan lens temperature may decrease. When processing resumes, corrections or compensation values ​​calculated when the scan lens temperature was higher may no longer be correct (e.g., due to changes in the scan lens's refractive index from temperature changes), resulting in errors in the beam spot position. Therefore, maintaining a stable scan lens temperature is important to enable accurate operation of the laser processing machine.

[0006] The embodiments described herein were developed in light of these and other problems discovered by the inventors.

[0007] One embodiment of the present invention can be characterized as a laser processing apparatus comprising a laser source capable of generating a beam of laser energy propagating along a beam path, a scan lens, and a debris removal system including a beam dump system capable of absorbing a portion of the laser energy beam, the scan lens being positioned along the beam path between the laser source and the debris removal system.

[0008] Another embodiment of the present invention may be characterized as a laser processing apparatus comprising a laser source capable of generating a beam of laser energy propagated along a beam path, a scan lens, and a beam dump system including an absorber selectively positionable within the beam path by an actuator assembly, the absorber capable of absorbing a portion of the laser energy beam, the scan lens being positioned along the beam path between the laser source and the beam dump system.

[0009] Another embodiment of the invention can be characterized as a system comprising: a debris removal system having a vacuum nozzle configured to allow a laser energy beam propagating along a beam path to pass therethrough; a vacuum source connected to the vacuum nozzle via an exhaust passage, the vacuum source configured to remove at least a portion of debris generated by the laser energy beam impinging on a workpiece from the vacuum nozzle; an exhaust facilitation system capable of directing fluid from an inlet port across the vacuum nozzle and into the exhaust passage, thereby forcing at least a portion of the debris into the exhaust passage; a beam dump system coupled to the debris removal system, the beam dump system including an absorber having an absorber surface formed thereon, the absorber surface configured to absorb at least a portion of the laser energy beam propagating along the beam path; and an actuator assembly operable to move the absorber relative to the debris removal system. [Brief explanation of the drawings]

[0010] [Figure 1] FIG. 1 is a schematic diagram of a laser processing device according to an embodiment.

[0011] [Figure 2] FIG. 2 shows a perspective view of a beam dump system according to one embodiment.

[0012] [Figure 3-4]3 and 4 show different positions of the beam dump system shown in FIG.

[0013] [Figure 5] FIG. 5 shows a schematic cross-sectional view of a debris removal system with an integrated beam dump system according to one embodiment.

[0014] [Figure 6] FIG. 6 shows a perspective view of a beam dump system according to one embodiment.

[0015] [Figure 7-8] 7 and 8 show different positional conditions of the debris removal system with integrated beam dump system shown in FIG. Detailed Description

[0016] Examples of embodiments will now be described with reference to the accompanying drawings. Unless explicitly stated, in the drawings, the sizes, positions, etc. of components, features, elements, etc., and the distances therebetween, are not necessarily to scale and have been exaggerated for clarity. Like numbers refer to like elements throughout the drawings. Thus, the same or similar numbers may be described with reference to other drawings even if they are not mentioned or described in the corresponding drawings. Also, elements without reference numbers may be described with reference to other drawings.

[0017] The terminology used in the specification is for the purpose of describing particular exemplary embodiments only and is not intended to be limiting. Unless otherwise defined, all terms (including technical and scientific terms) used herein have the same meaning as commonly understood by one of ordinary skill in the art. As used herein, the singular is intended to include the plural unless the content clearly dictates otherwise. Furthermore, it should be understood that the terms "comprises" and / or "comprising," when used herein, specify the presence of stated features, integers, steps, operations, elements, and / or components, but do not exclude the presence or addition of one or more other features, integers, steps, operations, elements, components, and / or groups thereof. Unless otherwise indicated, when a range of values ​​is recited, the range includes the upper and lower limits, as well as any subranges between the upper and lower limits of the range. Unless otherwise indicated, terms such as "first" and "second" are used merely to distinguish elements from one another. For example, one node can be referred to as a "first node," and similarly, another node can be referred to as a "second node," or vice versa.

[0018] Unless otherwise indicated, "about," "around," and the like mean that amounts, sizes, compositions, parameters, and other quantities and characteristics are not, and need not be, exact, but may be approximate and / or larger or smaller, as appropriate, or to reflect tolerances, conversion factors, rounding, measurement error, and the like, as well as other factors known to those skilled in the art. Spatially relative terms such as "below," "down," "lower," "upper," and "upper" may be used herein for ease of description when describing the relationship of an element or feature to another element or feature, as shown in the figures. It should be understood that spatially relative terms are intended to encompass different orientations in addition to those depicted in the figures. For example, an element described as being "below" or "below" another element or feature would be oriented "above" that other element or feature if the object in the figure were inverted. Thus, the exemplary term "below" can encompass both an orientation of above and below. If the object is oriented in other ways (e.g., rotated 90 degrees or at other orientations), the spatially relative descriptors used herein may be interpreted accordingly.

[0019] The section headings used herein, unless specifically stated, are for organizational purposes only and should not be construed as limiting the subject matter described. It will be understood that many different forms, embodiments, and combinations are possible without departing from the spirit and teachings of the present disclosure, and that the present disclosure should not be construed as limited to the example embodiments set forth herein. Rather, these examples and embodiments are provided so that this disclosure will be complete and all-inclusive, and will fully convey the scope of the disclosure to those skilled in the art.

[0020] I. System Overview FIG. 1 is a schematic diagram showing a laser processing apparatus according to an embodiment of the present invention.

[0021] 1 , a laser processing apparatus 100 (also referred to herein simply as “apparatus”) for processing a workpiece can be characterized as including a laser source 104 for generating a laser energy beam, a first positioner 106, a second positioner 108, a third positioner 110, and a scan lens 112. The scan lens 112 and one of the positioners can be integrated into a common housing or “scan head” 120, if desired. For example, the scan lens 112 and the second positioner 108 can be integrated into the common scan head 120. Each of the first positioner 106 and the second positioner 108 can diffract, reflect, refract, or otherwise deflect the laser energy beam 116 to vary a beam path 114 traversed by the laser energy in the laser energy beam as it propagates from the laser source 104 to the scan lens 112. Scan lens 112 focuses the incident laser energy beam, which ultimately reaches workpiece 102. While FIG. 1 illustrates laser processing apparatus 100 as including first positioner 106 and second positioner 108, it will be understood that one or both of these optical components may be omitted from laser processing apparatus 100, if desired. Similarly, third positioner 110 may be omitted, if desired. Although not shown, laser processing apparatus 100 may include one or more other optical components (such as mirrors, lenses, polarizers, wave plates, apertures, beam expanders, beam shapers, wavefront compensation optics, relay optics, etc., or any combination thereof (also referred to herein as "optical components")) disposed in the beam path between laser source 104 and scan lens 112.

[0022] In one embodiment, the apparatus 100 may include a beam dump system 140 capable of blocking the laser energy beam 116 from reaching the workpiece 102. In another embodiment, the apparatus 100 may include a debris removal system 200 capable of collecting at least a portion of the debris (e.g., particles, processing by-products, gases, vapors, etc.) generated by processing the workpiece 102. Optionally, the debris removal system 200 may include an integrated beam dump system 300 capable of blocking the laser energy beam 116 from reaching the workpiece 102. If the beam dump system 300 is integrated with the debris removal system 200, the beam dump system 140 may be omitted. Although FIG. 1 shows the beam dump system 140 as being below the debris removal system 200, the beam dump system 140 may also be located above the debris removal system 200 (i.e., between the scan lens 112 and the debris removal system 200).

[0023] Generally, apparatus 100 includes one or more controllers, such as controller 122, that control or facilitate the control of operation of apparatus 100. In one embodiment, controller 122 is communicatively coupled (e.g., via one or more wired or wireless serial or parallel communication links, such as USB, RS-232, Ethernet, Firewire, Wi-Fi, RFID, NFC, Bluetooth, Li-Fi, SERCOS, MARCO, EtherCAT, etc., or any combination thereof) to one or more components of apparatus 100, such as laser source 104, first positioner 106, second positioner 108, third positioner 110, scan lens 112 (if implemented as a variable focal length lens), etc., such that these components can operate in response to one or more control signals output by controller 122.

[0024] The apparatus 100 may also include a vacuum source 130, an evacuation-enhancing fluid pressure source 132, an actuator fluid pressure source 134, and a heat transfer fluid source 136. As described in more detail below, these fluid or vacuum sources 130, 132, 134, 136 may be coupled in various ways to the debris removal system 200 and the beam dump system 140 or 300 to facilitate operation of the debris removal system 200 and the beam dump system 140 or 300.

[0025] II. Example Embodiments of Beam Dump and Debris Removal Systems As described above, during operation of the apparatus 100, the scan lens 112 and other optical components may change in temperature as portions of the laser energy beam 116 are absorbed. If necessary, the apparatus 100 may measure and calibrate laser beam parameters (e.g., spot size, focal position, etc.) and the position of the laser spot (e.g., measured position relative to predicted position) using a beam characterization tool (not shown) located optically downstream of the beam delivery optics. The results of these measurements or calibrations may be used to calculate corrections to predicted beam placement or to compensate for suboptimal beam characteristics. As the apparatus 100 processes the workpiece 102 (and during beam characterization), and the beam passes through all of the beam path optics, the temperature of the beam delivery optics (e.g., scan lens 112) may reach a steady state. During periods when the apparatus 100 is not being characterized or processing a workpiece 102 (e.g., during system idle, workpiece loading or unloading, workpiece inspection, etc.), the beam may be blocked (e.g., by a laser shutter, modulator, or beam dump located optically upstream of the scan lens 112) before reaching the scan lens 112. During these periods, the temperature of the scan lens 112 may decrease. When processing resumes, corrections or compensation values ​​calculated when the scan lens 112 was warmer may no longer be correct (e.g., due to changes in the refractive index of the scan lens 112 from changes in temperature), resulting in errors in the beam spot position. The following is a description of example embodiments that may be used to allow the laser energy beam 116 to pass through the scan lens 112 under all operating conditions by placing a beam dump optically downstream of the scan lens 112.

[0026] a.Beam dump system 2 illustrates a perspective view of an exemplary beam dump system 140 shown in a retracted position. As shown, the beam dump system 140 can include an absorber 142, an actuator assembly 150 capable of selectively positioning the absorber 142, and a heat transfer system 160 capable of transferring heat away from the absorber 142.

[0027] The absorber 142 may include an absorber surface 144 formed thereon or attached thereto. The absorber surface 144 is formed from a material selected to absorb the laser energy beam 116 (e.g., steel, brass, aluminum, copper, copper-tungsten, silicon carbide, etc., or any combination thereof). The absorber surface 144 may also have surface features (e.g., raised or depressed areas, depressions, etc.) configured to enable absorption of the laser energy beam 116 and minimize reflection of the laser energy beam 116 back toward the scan lens 112 and laser source 104. Alternatively, the formed absorber surface 144 may be provided as a light-absorbing surface (e.g., a roughened, anodized, or oxidized surface) configured to enhance absorption of the laser energy beam 116. The absorber surface 144 may be coated (e.g., via an electrolytic plating process, an electroless plating process, a vacuum deposition process, a painting process, or the like, or any combination thereof) with a material that is suitably absorptive of the incident laser energy beam 116.

[0028] The actuator assembly 150 may be provided as a pneumatic or hydraulic cylinder assembly including an actuator cylinder 152 having an actuator piston 154 including an insulator 156 configured to couple the actuator piston 154 to the absorber 142. The insulator 156 may be formed from a material (e.g., a composite, ceramic, a high-temperature polymer, or the like, or any combination thereof) selected to reduce the amount of heat transferred from the absorber 142 to the actuator piston 154 and the actuator cylinder 152, thereby preventing damage to seals or other components of the actuator assembly 150. The actuator assembly 150 may include fluid ports 158 and 159 located at opposite ends of the actuator cylinder 152, in communication with the actuator fluid pressure source 132, and configured to allow fluid to enter and exit the cylinder 152 to extend or retract the actuator piston 154.

[0029] The heat transfer system 160 may be provided as a heat sink, a Peltier heat pump, a water block, or the like, or any combination thereof. As shown in FIG. 2 , in one embodiment, the heat transfer system 160 may circulate a heat transfer fluid (e.g., a gas, liquid, or vapor provided by a heat transfer fluid source 136) through the absorber 142 to transfer heat away from the absorber surface 144 (e.g., entering the inlet 162, flowing through channels 164, 166, and 168 formed in the absorber 140, and exiting through an outlet 170 (see also FIG. 4 )). A thermal sensor 172 capable of sensing the temperature of the absorber 142 may be provided on or in thermal communication with the absorber 142. During operation, the thermal sensor 172 may send a signal proportional to the temperature of the absorber 142 to the controller 122 and / or the heat transfer fluid source 136 to enable control of the rate of heat transfer from the absorber 142. In other embodiments, the heat transfer system 160 may be provided as a dissipative heat sink or heat pump that is thermally coupled to the absorber 142 and the absorber surface 144 .

[0030] 3 and 4 show cross-sectional views of an exemplary embodiment of beam dump system 140 in different positions during different operational modes of apparatus 100. FIG. 3 shows a cross-sectional view of beam dump system 140 with actuator assembly 150 retracting absorber 142 to allow laser energy beam 116 to propagate along beam path 114, through scan lens 112, and to workpiece 102 (e.g., for processing workpiece 102). Actuator assembly 150 may be secured (e.g., by screws, adhesive, clamps, etc., or any combination thereof) to an actuator mount 190 located on a structure (e.g., a gantry) separate from scan head 120 and third positioner 110. If desired, actuator assembly 150 may be attached to or integrally formed with scan head 120 or second positioner 108. Actuator assembly 150 may also be fixed relative to scan head 120 and third positioner 110. In other embodiments, absorber 142 may be selectively positioned between scan lens 112 and workpiece 102 by a separate positioner (not shown).

[0031] 4 illustrates a cross-sectional view of beam dump system 140 shown in an extended position with absorber 142 positioned in beam path 114. Actuator assembly 150 positions absorber 142 in beam path 114 by extending actuator piston 154 (e.g., in response to one or more control commands from controller 122 or actuator fluid pressure source 134 shown in FIG. 1). As shown, laser energy beam 116 propagates through scan lens 112 but is incident on absorber surface 144 rather than workpiece 102. When absorber 142 is positioned in beam path 114, heat transfer system 160 is used as needed to control the transfer of heat away from absorber 142 and absorber surface 144 (e.g., in response to commands from controller 122 and / or heat transfer fluid source 136 shown in FIG. 1). Heat transfer fluid from heat transfer fluid source 136 (shown in FIG. 1) enters through inlet 162 (as shown in FIG. 2), passes through passage 164, passes through passage 166 below absorber surface 144, passes through passage 168, and exits through outlet 170. Insulation 156 may prevent residual heat from damaging actuator assembly 150.

[0032] b. Debris removal system with integrated beam dump system In some cases, particularly if the apparatus includes a debris removal system, there may be little or no space for a beam dump system between the scan lens 112 and the workpiece 102. Accordingly, one embodiment of the present invention may be broadly characterized as integrating a beam dump system 300 into the debris removal system 200. One or more beam dump systems 300 may be located or integrated within or adjacent to the debris removal system 200 such that elements of the beam dump system 300 can be selectively positioned in the beam path 114 when needed (e.g., upon command by the controller 122) without requiring additional space between the scan lens 112 and the workpiece 102. To operate the debris removal system 200 and the beam dump system 300, the apparatus 100 may include one or more vacuum or fluid pressure sources or controllers configured to provide vacuum or fluid pressure to the debris removal system 200 and the beam dump system 300. In the illustrated embodiment, four such sources are provided, including a vacuum source 130, an exhaust-boosting fluid pressure source 132, an actuator fluid pressure source 134, and a heat transfer fluid source 136. In the illustrated embodiment, the debris removal system 200 is located on a structure (e.g., a gantry) that is independent of the scan head 120 and the third positioner 110. If desired, the debris removal system 200 can be attached to or integrally formed with the scan head 120 or the second positioner 108. The debris removal system 200 can be fixed relative to the scan head 120 and the third positioner 110, or can be selectively positioned between the scan lens 112 and the workpiece 102 by a separate positioner (not shown).

[0033] 5 shows a schematic cross-sectional view of a debris removal system 200 with an integrated beam dump system 300 according to one embodiment. The debris removal system 200 may include a debris removal housing 210 having a vacuum nozzle 212 and an exhaust passage 216 formed therein that communicates with the vacuum source 130. A plate or cover 214 may be secured to the debris removal housing 210 (e.g., by screws, adhesive, clamps, etc., or any combination thereof) that is positioned to prevent ambient air from entering the exhaust passage 216 without first entering the vacuum nozzle 212. Optionally, the cover 214 may be integrally formed with the debris removal housing 210. The vacuum nozzle 212 may define a window or opening positioned and dimensioned to allow the laser energy beam 116 to pass therethrough as it propagates from the scan lens 112 along the beam path 114 (e.g., to process the workpiece 102). Debris 270 (e.g., gases, vapors, processing by-products, or particulate matter such as metals, silicon, polymers, etc., shown as speckle stream 270) generated by the laser machining process can be drawn into the vacuum nozzle 212 and subsequently advected into the exhaust channel 216. An exhaust manifold 240, positioned in communication with the vacuum source 130, may be located on the debris removal housing 210. Optionally, the debris removal housing 210 and the exhaust manifold 240 may form a monolithic structure. The exhaust manifold 240 defines an exhaust channel 242 and an exhaust port 244. The exhaust channel 242 is configured to allow the debris 270 to pass through the exhaust channel 242 and exit through the exhaust port 244.

[0034] The debris removal system 200 may also include an exhaust facilitation system 280. The exhaust facilitation system 280 may be capable of providing a flow 286 of fluid (e.g., air or other gas) provided by an exhaust facilitation fluid pressure source 132 (also referred to herein as “fluid pressure source 132”) shown in FIG. 1 to force the debris 270 into the exhaust flow path 216. The exhaust facilitation system 280 may include an exhaust facilitation body 282 having a plenum 288 formed therein. The plenum 288 is configured to receive the fluid 286 (e.g., from the fluid pressure source 132) via ports 284. The exhaust facilitation body 282 may have one or more ports 290 formed therein that are configured to generate one or more fluid flows 286 that may flow across the vacuum nozzle 212 toward the exhaust flow path 216. The ports 290 may also be positioned and configured to generate a high-velocity stream or curtain of the fluid 286 that flows across the vacuum nozzle 212.

[0035] The vacuum nozzle 212 may also be sized to accommodate the components of the beam dump system 300 therein. Similar to the beam dump system 140, the beam dump system 300 may be capable of selectively positioning an absorber 320 to absorb at least a portion of the laser energy beam 116 propagating along the beam path 114. The beam dump system 300 may be secured to an actuator mount 230 formed on or attached to the debris removal housing 210 or the exhaust manifold 240 (e.g., by screws, adhesive, clamps, etc., or any combination thereof). The beam dump system 300 may also include an actuator assembly 400 capable of selectively positioning the absorber 320 within a window or opening defined by the vacuum nozzle 212 and onto the beam path 114 (e.g., by extension or contraction of the actuator piston 154 in response to control commands from the controller 122 and / or the actuator fluid pressure source 134).

[0036] During operation of the apparatus 100, when the laser energy beam 116 is processing the workpiece 102, generated debris 270 may be drawn and advected into the exhaust channel 216 (e.g., by fluid flow 286 from the exhaust facilitation system 280, by a vacuum drawn at the exhaust port 244 by the vacuum source 130, or a combination thereof). When the apparatus 100 is not processing a workpiece (e.g., during system idle, workpiece loading or unloading, workpiece inspection, etc.), the actuator assembly 400 (e.g., in response to commands from the controller 122) may actuate the actuator piston 154 to position the absorber 320 within the vacuum nozzle 212 and beam path 114. Once the absorber 320 is positioned within the beam path 114, the exhaust facilitation system 280 may be disengaged from the vacuum source 130 (e.g., because debris is not being generated by the laser energy beam 116). Alternatively, the exhaust enhancement system 280 may be maintained in communication with the vacuum source 130 when the absorber 320 is positioned in the beam path 114 .

[0037] FIG. 6 illustrates a perspective view of the beam dump system 300 shown in a retracted position. As illustrated, the beam dump system 300 includes the absorber 320 described above, an actuator assembly 400 capable of selectively positioning the absorber 320, and a heat transfer system 500 capable of transferring heat away from the absorber 320. In one embodiment, the absorber 320 is configured similarly to the absorber 142. However, it will be appreciated that the absorber 320 may be configured in any other suitable or desired configuration. However, according to this embodiment, one or more recesses 324 including one or more tapered regions or sidewalls 326 may be formed on the absorber 320. The recesses 324 may be configured such that the absorber 320 does not restrict the transition from the vacuum nozzle 212 to the exhaust channel 216 when the absorber 320 is in the retracted position (as shown in FIG. 7). This allows for efficient flow of debris 270 from the vacuum nozzle 212 to the exhaust channel 216. The absorber 320 may also include one or more baffles 328 configured to concentrate the flow of air and debris into the vacuum nozzle 212 and the exhaust flow path 216 by blocking at least a portion of the ambient air from entering the vacuum nozzle 212 when the absorber 320 is in the retracted position.

[0038] In one embodiment, actuator assembly 400 is provided similarly to actuator assembly 150. However, it will be appreciated that actuator assembly 400 may be provided in any other suitable or desired configuration.

[0039] Heat transfer system 500 is thermally coupled to or integrated with absorber 320 and configured to transfer heat away from absorber 320. In one embodiment, heat transfer system 500 is provided similarly to heat transfer system 160. However, it will be appreciated that heat transfer system 500 may be provided in any other suitable or desired configuration.

[0040] 7 and 8 show cross-sectional views of different positions of the beam dump system 300 during different operational modes of the apparatus 100. Figure 7 shows a cross-sectional view of the debris removal system 200 with the actuator assembly 400 causing the absorber 320 of the beam dump system 300 to retract, thereby allowing the laser energy beam 116 to propagate along the beam path 114 and through the scan lens 112 (e.g., to process the workpiece 102). In this operational mode, debris 270 generated by the laser energy beam 116 processing the workpiece 102 can be sucked into the vacuum nozzle 212, into the exhaust passage 216 of the debris removal housing 210, into the exhaust passage 242 of the exhaust manifold 240, and out the exhaust port 244. Fluid 286 exiting the port 290 of the exhaust facilitation system 280 traverses the vacuum nozzle 212 and pushes the debris 270 into the exhaust passage 216. As described above, the tapered region 326 of the recess 324 formed in the absorber 320 may deflect the debris 270 into the exhaust passage 216, thereby providing a smooth transition from the vacuum nozzle 212 to the exhaust passage 216 so that the debris flows from the vacuum nozzle 212 to the exhaust passage 216. The baffle 328 formed on the absorber 320 and the cover 214 attached to the debris removal housing 210 help prevent ambient air from entering the exhaust passage 216 and reducing the vacuum drawn by the vacuum source 130, thereby ensuring that the debris 270 is effectively removed from the vacuum nozzle 212.

[0041] 8 illustrates a debris removal system 200 in which a beam dump system 300 is disposed within a vacuum nozzle 212 in the beam path 114. An actuator assembly 400 positions an absorber 320 and an absorber surface 144 within the vacuum nozzle 212 and the beam path 114 by extending an actuator piston 154 (e.g., in response to one or more control commands from the controller 122 or the actuator fluid pressure source 134 shown in FIG. 1). As shown, a laser energy beam 116 propagates through the scan lens 112 but is incident on the absorber surface 144 rather than the workpiece 102. When the absorber 320 is positioned in the beam path 114, a heat transfer system 500 may operate as needed (e.g., in response to commands from the controller 122 and / or the heat transfer fluid source 136 shown in FIG. 1) to control the transfer of heat away from the absorber 320 and the absorber surface 144. Insulation 156 may prevent residual heat from damaging actuator assembly 400. Heat transfer fluid from heat transfer fluid source 136 (shown in FIG. 1) enters through inlet 162 (as shown in FIG. 6), flows through passage 164, flows through passage 166 below absorber face 144, is directed to passage 168, and exits through outlet 170. In one embodiment, the heat transfer fluid may be directed to a heat exchanger or chiller (not shown) configured to extract heat from the heat transfer fluid. Cover 214 helps support absorber 320 in the extended position. As mentioned above, when absorber 320 is extended, no debris is being generated and therefore evacuation facilitation system 280 may be disconnected from vacuum source 130. Optionally, both the exhaust facilitation system 280 and the vacuum source 130 may remain operational as needed (e.g., to expel residual debris from the vacuum nozzle 212 through the exhaust passage 216 and the exhaust passage 242 and out the exhaust port 244).

[0042] III. Conclusion The foregoing describes embodiments and examples of the present invention and is not to be construed as limiting thereof. While several specific embodiments and examples have been described with reference to the drawings, those skilled in the art will readily recognize that many modifications to the disclosed embodiments and examples and other embodiments are possible without materially departing from the novel teachings and advantages of the present invention. Accordingly, all such modifications to the subject matter described above are intended to be included within the scope of the present invention as defined in the claims. For example, those skilled in the art will understand that the subject matter of any sentence, paragraph, example, or embodiment can be combined with part or all of the subject matter of any other sentence, paragraph, example, or embodiment, except where such combinations are mutually exclusive. Therefore, the scope of the present invention should be determined by the following claims and any equivalents of such claims to be included therein.

Claims

1. a laser source capable of generating a beam of laser energy propagated along a beam path; a scan lens configured to direct the beam of laser energy onto a workpiece; a debris removal system capable of collecting at least a portion of debris generated by processing the workpiece, the debris removal system including a beam dump system including an absorber capable of absorbing a portion of the laser energy beam; Equipped with the scan lens is positioned along the beam path between the laser source and the debris removal system; the absorber is configured to be selectively positioned in the beam path between the scan lens and the workpiece. Laser processing equipment.

2. 2. The laser processing apparatus of claim 1, wherein the beam dump system includes an actuator assembly capable of selectively positioning the absorber in the beam path between the scan lens and the workpiece.

3. The debris removal system comprises: a vacuum nozzle in communication with a vacuum source via an exhaust passage, the vacuum source configured to remove at least a portion of the debris generated by the laser energy beam impinging on the workpiece from the vacuum nozzle; an exhaust facilitation system capable of forcing at least a portion of the debris into the exhaust passage by directing fluid from an inlet port across the vacuum nozzle and into the exhaust passage; The laser processing device according to claim 1 , further comprising:

4. The laser processing apparatus of claim 1 , wherein the beam dump system includes a heat transfer system capable of transferring heat away from the absorber.

5. The heat transfer system comprises: an inlet configured to receive a heat transfer fluid capable of absorbing heat within the absorber; The exit and a flow path disposed within the absorber and configured to direct the fluid from the inlet to the outlet; a thermal sensor in thermal communication with the absorber, the thermal sensor configured to sense a temperature of the fluid and send a temperature signal to a controller; The laser processing device according to claim 4 , comprising:

6. a debris removal system capable of collecting at least a portion of debris generated by processing the workpiece, the debris removal system having a vacuum nozzle configured to allow the laser energy beam propagating along a beam path to pass therethrough; a vacuum source connected to the vacuum nozzle via an exhaust passage, the vacuum source configured to remove at least a portion of the debris generated by the laser energy beam impinging on a workpiece from the vacuum nozzle; an exhaust facilitation system operable to direct fluid from an inlet port across the vacuum nozzle and into the exhaust passage to force at least a portion of the debris into the exhaust passage; a beam dump system coupled to the debris removal system, an absorber configured to absorb at least a portion of the laser energy beam propagating along the beam path toward the workpiece; an actuator assembly capable of selectively positioning the absorber within the beam path; a beam dump system including A system comprising:

7. The system of claim 6 , wherein the beam dump system is integrated into the debris removal system.

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