Laser processing device

Abstract

The present invention can provide a laser processing apparatus having a nozzle capable of suppressing contamination of a cover glass. A laser processing apparatus according to the present invention is provided with: a laser processing head that irradiates a laser beam onto a workpiece; and a side nozzle that ejects the gas introduced from the introduction port from the slit-shaped ejection port on an optical path from the laser processing head to the workpiece, the introduction port of the side nozzle introducing the gas from a direction inclined with respect to the direction in which the gas is ejected from the ejection port, and the side nozzle ejecting the gas from the slit-shaped ejection port. The flow path for guiding the gas introduced from the introduction port to the discharge port has a first flow path for guiding the gas from the introduction port to the discharge port in the longitudinal direction of the discharge port, and a second flow path for guiding the gas discharged from the first flow path to the discharge port. The shape of the inner side of the first flow path gradually narrows as the first flow path moves away from the introduction port in the gas introduction direction.

Description

Technical Field

[0001] This invention relates to a laser processing apparatus. Background Technology

[0002] When processing a workpiece using a laser processing device, spatter or fumes from the sublimation of metal contained in the workpiece may adhere to the optical system of the laser processing head, such as mirrors or lenses. Therefore, a protective glass is installed in the laser processing head to protect the optical system from spatter or fumes. However, if spatter or fumes adhere to this protective glass, the laser processing device may be unable to properly focus the laser beam onto the processing point on the workpiece.

[0003] To protect protective glass from debris or dust, for example, Patent Document 1 discloses a laser processing apparatus that includes a nozzle that ejects gas from one side to the other in a manner that cuts across the optical path of the laser beam. This laser processing apparatus prevents debris or dust from adhering to the protective glass by causing the gas to flow from the nozzle in a direction that cuts across the optical path of the laser beam.

[0004] Patent Document 1: Japanese Patent Application Publication No. 2023-121375 Summary of the Invention

[0005] From the perspective of reducing carbon dioxide emissions, it is necessary to reduce the amount of gas supplied to the nozzle. However, if the amount of gas supplied is reduced, the amount of gas ejected from the nozzle will also be reduced, which may cause contamination of the protective glass by splashes or soot from the ejected gas. Therefore, there is a need for a nozzle that can ensure a sufficient ejection volume even if the amount of gas supplied to the nozzle is reduced.

[0006] The present invention was made to solve this problem by providing a laser processing apparatus having a nozzle capable of suppressing contamination of the protective glass.

[0007] The laser processing apparatus of the present invention includes: a laser processing head that irradiates a workpiece with a laser beam; and a side nozzle that ejects gas introduced from an inlet from a slit-shaped outlet along an optical path from the laser processing head to the workpiece. The inlet of the side nozzle introduces the gas in a direction inclined relative to the ejection direction of the gas from the outlet. A flow path guiding the gas introduced from the inlet to the outlet has a first flow path and a second flow path. The first flow path guides the gas from the inlet to the outlet along the length direction of the outlet, and the second flow path guides the gas flowing out of the first flow path to the outlet. The inner shape of the first flow path gradually narrows as it moves away from the inlet in the direction of gas introduction. Thus, the side nozzle can homogenize the flow velocity of the gas ejected from the outlet along the length direction of the outlet.

[0008] The width of the second flow path, viewed along the length of the nozzle, can first widen and then narrow towards the nozzle. The gas introduced into the side nozzle is rectified at the point where the second flow path widens first. Therefore, the side nozzle can reduce gas pressure loss.

[0009] The side nozzle may have multiple nozzle outlets, which are arranged in one or more rows along the length of the nozzle outlet. By arranging multiple nozzle outlets, the side nozzle can increase the flow rate of the gas ejected from the nozzle outlet.

[0010] The width of the second flow path, when viewed from the width direction of the nozzle, can widen as it approaches the nozzle. Therefore, the side nozzle can eject gas over a wide range relative to the length direction of the nozzle.

[0011] The side nozzle may have an external air flow path separate from the flow path. When viewed from the width direction of the nozzle outlet, the external air flow path is arranged to sandwich the second flow path. Both ends of the external air flow path are in communication with external air. When the gas is ejected from the nozzle outlet of the side nozzle, external air is ejected from one end of the external air flow path located near the nozzle outlet. As a result, the flow velocity of the gas ejected from the nozzle outlet is increased by the external air ejected from one end of the external air flow path.

[0012] Invention Effects

[0013] This invention provides a laser processing apparatus equipped with a nozzle capable of suppressing contamination of the protective glass. Attached Figure Description

[0014] Figure 1 This is a diagram illustrating the structure of the laser processing apparatus involved in this invention.

[0015] Figure 2 This is a perspective view of the side nozzle involved in Embodiment 1.

[0016] Figure 3 The above figure is a side view of the side nozzle according to Embodiment 1. Figure 3 The following figure is a bottom view of the side nozzle according to Embodiment 1.

[0017] Figure 4 The above figure is a diagram showing the side nozzle according to Embodiment 1. Figure 4 The following diagram is a diagram showing the side nozzle involved in Embodiment 2.

[0018] Figure 5 It is along Figure 4 The following figure is a cross-sectional view cut by the VV section line.

[0019] Figure 6 The figure above shows the fluid analysis results of the side nozzle involved in Embodiment 1. Figure 6 The following figure shows the fluid analysis results of the side nozzle involved in Embodiment 2. Detailed Implementation

[0020] Hereinafter, specific embodiments of the present invention will be described in detail with reference to the accompanying drawings. However, the present invention is not limited to the following embodiments. Furthermore, for the sake of clarity, the following description and drawings are appropriately simplified.

[0021] (Implementation Method 1)

[0022] <Structure of Laser Processing Equipment>

[0023] First, refer to Figure 1 The structure of the laser processing apparatus involved in Embodiment 1 will be described. Figure 1 This is a diagram showing the structure of the laser processing apparatus according to the present invention. The laser processing apparatus 1 is an apparatus for performing laser processing such as welding, cutting, drilling, and engraving on a workpiece W. The laser processing apparatus 1 includes a laser processing head 10, a laser oscillator 20, a gas supply unit 30, a side nozzle 40, and a processing point nozzle 50.

[0024] The laser processing head 10 is used to irradiate the workpiece W with a laser beam LB. The laser processing head 10 includes an optical system (not shown) and a protective glass. The optical system is used to focus or refract the laser beam transmitted from the laser oscillator 20 via a fiber optic cable onto the workpiece W. The optical system may include, for example, a lens, a mirror, or a filter. To prevent splatter from the workpiece W melting and splashing during laser processing, or fumes from the sublimation of metal contained in the workpiece W, from adhering to the optical system, a protective glass is provided on the laser processing head 10. Furthermore, the laser processing head 10 can be mounted on a robot, for example. In this case, the position of the laser processing head 10 relative to the workpiece W can be changed by moving the robot.

[0025] The laser oscillator 20 is connected to the laser processing head 10 via an optical fiber cable. The laser oscillator 20 emits a laser beam LB through the optical fiber cable by oscillation. The laser oscillator 20 emits the laser beam LB according to an output command signal input from a laser oscillator control unit (not shown), which instructs the output of the laser beam LB. The laser oscillator 20 can use, for example, a solid-state laser source, a gas laser source, or a fiber laser source as its light source.

[0026] The gas supply unit 30 uses a pump (not shown) to pressurize gas to the housing 11, the side nozzle 40, and the processing point nozzle 50. Furthermore, the gas supplied by the gas supply unit 30 is not limited to air; it can also be other gases such as nitrogen.

[0027] A housing 11 is mounted near the ejection port of the laser processing head 10. The housing 11 is configured to cover the ejection port or protective glass and to prevent foreign matter such as splatter or dust from adhering to the protective glass. A flow path for supplying gas is provided within the housing 11. The gas supplied to the housing 11 is ejected from a predetermined position within the housing 11, thereby generating an airflow AR1. The airflow AR1 prevents foreign matter such as splatter or dust from adhering to the protective glass. Alternatively, the laser processing head 10 of the present invention may be provided without the housing 11.

[0028] The side nozzle 40 ejects gas to generate an airflow AR2. The side nozzle 40 is sometimes referred to as an air knife. The side nozzle 40 ejects gas along the optical path of the laser beam LB between the laser processing head 10 and the workpiece W to generate a generally planar airflow AR2. During laser processing, the airflow AR2 washes away spatter or dust that splashes from the processing point W0 toward the laser processing head 10. Therefore, the side nozzle 40 can suppress spatter or dust from reaching the laser processing head 10 through the airflow AR2. Here, to prevent foreign matter washed away by the airflow AR2 from adhering to the workpiece W, the airflow AR2 preferably does not overlap with the workpiece W. Furthermore, the structure of the side nozzle 40 will be described in detail later.

[0029] The machining point nozzle 50 is positioned closer to the workpiece W than the side nozzle 40. The machining point nozzle 50 ejects gas to generate an airflow AR3. The machining point nozzle 50 generates an airflow AR3 in a generally conical range covering the machining point W0. During laser processing, the airflow AR3 washes away the dust generated from the workpiece W. Therefore, the machining point nozzle 50 can suppress dust from reaching the laser processing head 10 through the airflow AR3. From the viewpoint of suppressing the decline in the function of each airflow, the ranges of airflow AR2 and airflow AR3 preferably do not overlap. Alternatively, the side nozzle 40 can be used instead of the machining point nozzle 50. Furthermore, the laser processing head 10 of the present invention may not have the machining point nozzle 50.

[0030] <Structure of the side nozzle>

[0031] Next, refer to Figure 2 and Figure 3 The structure of the side nozzle 40 will be explained. Figure 2 This is a perspective view of the side nozzle according to Embodiment 1. Figure 3 middle, Figure 3 The above figure is a side view of the side nozzle according to Embodiment 1. Figure 3 The following figure is a bottom view of the side nozzle according to Embodiment 1. The side nozzle 40 includes an inlet 41, an outlet 42, and a flow path 43. Furthermore, in Figure 2 and Figure 3 In the middle, the outline of the side nozzle 40 is represented by a double-dotted line, and the gas flowing through the side nozzle 40 is represented by a solid line.

[0032] Furthermore, in the following description, a three-dimensional orthogonal coordinate system of xyz will be appropriately used. In this embodiment 1, the length direction of the nozzle 42 is defined as the x-direction, the width direction of the nozzle 42 is defined as the y-direction, and the normal direction of the nozzle 42 is defined as the z-direction.

[0033] The inlet 41 is an opening for introducing gas from the gas supply unit 30 into the side nozzle 40. More specifically, the inlet 41 introduces gas into the side nozzle 40 in a direction inclined relative to the ejection direction (+z direction) of the gas from the outlet 42. In this embodiment 1, the inlet 41 is provided in the yx plane relative to the side nozzle 40. In addition, the inlet 41 is connected to the gas supply unit 30 via a pipe P.

[0034] The nozzle 42 is a slit-shaped opening for ejecting gas introduced into the side nozzle 40. The gas ejected from the nozzle 42 becomes... Figure 1The airflow AR2 is shown. Multiple nozzles 42 are provided in the side nozzle 40. These multiple nozzles 42 are arranged in one or more rows along the length direction (x-direction) of the nozzle 42. By arranging multiple nozzles 42, the side nozzle 40 can increase the flow velocity of the gas ejected from the nozzles 42.

[0035] Multiple nozzle outlets 42 are formed by dividing the openings of the side nozzle 40 into multiple parts by partitions C arranged at predetermined intervals. The partitions C are formed by crimping a portion of the side nozzle 40, but are not limited to this. For example, the partitions C can be formed by threaded connection. In addition, the nozzle outlets 42 can also be formed by machining or the like. Alternatively, the side nozzle 40 may not be divided into multiple nozzle outlets 42, and the opening itself may be directly provided as a nozzle outlet 42.

[0036] A flow path 43 is disposed within the side nozzle 40, guiding gas introduced from the inlet 41 to the outlet 42. The flow path 43 includes: a first flow path 43a, guiding gas from the inlet 41 to the outlet 42 along the length direction (+x direction) of the outlet 42; and a second flow path 43b, guiding gas flowing out of the first flow path 43a to the outlet 42. Figure 3 As shown in the figure above, in flow path 43, the side closer to the -z direction than the dashed line is designated as the first flow path 43a, and the side closer to the +z direction than the dashed line is designated as the second flow path 43b. Furthermore, in this embodiment 1, the position where flow path 43 is divided into the first flow path 43a and the second flow path 43b is... Figure 3 The image above is indicated by a dashed line, but there is no specific limitation on the location.

[0037] like Figure 3 As shown, the inner shape of the first flow path 43a gradually narrows as it moves away from the inlet 41 toward the gas inlet direction (+x direction). Therefore, the flow path 43 can guide a large amount of gas to the outlet 42 on the side near the inlet 41 (-x direction side). Consequently, the side nozzle 40 can reduce the difference in gas velocity between the outlet 42 near the inlet 41 (-x direction side) and the outlet 42 away from the inlet 41 (+x direction side). In other words, the side nozzle 40 can homogenize the gas velocity ejected from the outlet 42 along the length direction (x direction) of the outlet 42.

[0038] like Figure 2 As shown, the width of the second flow path 43b, viewed from the length direction (x direction) of the nozzle 42, first widens and then narrows towards the nozzle 42 (+z direction). Therefore, the gas introduced into the side nozzle 40 is rectified at the widening portion of the second flow path 43b. This reduces pressure loss of the gas passing through the flow path 43.

[0039] like Figure 3 As shown in the figure above, the width of the second flow path 43b, when viewed from the width direction (y-direction) of the nozzle 42, increases towards the nozzle 42 (+z-direction). Therefore, the side nozzle 40 can eject gas over a greater range relative to the length direction (x-direction) of the nozzle 42.

[0040] As explained above, the side nozzle 40 according to Embodiment 1 can uniformly distribute the flow velocity of the gas ejected from the nozzle 42 along the length direction (x direction) of the nozzle 42. Furthermore, the side nozzle 40 can more effectively rectify the gas passing through the flow path 43, thus reducing pressure loss. Therefore, even if the gas supply to the side nozzle 40 is reduced, the side nozzle 40 can still eject gas with a sufficient flow velocity over a wide range along the length direction (x direction) of the nozzle 42, thereby suppressing contamination of the protective glass.

[0041] (Implementation Method 2)

[0042] The laser processing apparatus according to Embodiment 2 will now be described. Furthermore, the laser processing apparatus according to Embodiment 2, except for the side nozzle 40, has the same structure as the laser processing apparatus according to Embodiment 1. Therefore, the structure of the side nozzle 40 according to Embodiment 2 will be described here.

[0043] <Structure of the side nozzle>

[0044] The following uses Figure 4 and Figure 5 Another example of a nozzle on the opposite side will be illustrated. Figure 4 middle, Figure 4 The above figure is a diagram showing the side nozzle according to Embodiment 1. Figure 4 The following diagram is a diagram showing the side nozzle involved in Embodiment 2. Figure 5 It is along Figure 4 The following figure shows a sectional view cut along the VV section line. Figure 4 As shown, the side nozzle 40 according to Embodiment 2 further includes an external air utilization section 44 compared to the side nozzle 40 according to Embodiment 1. The side nozzle 40 according to Embodiment 2 has two external air utilization sections 44. Furthermore, the two external air utilization sections 44 are arranged in the side nozzle 40 such that they sandwich the second flow path 43b. Additionally, the external air utilization section 44 may be only on one side.

[0045] The external air utilization unit 44 includes an external air flow path 45. The external air flow path 45 is separate from and not connected to the flow path 43. For example, multiple external air flow paths 45 are formed by separating the interior of the external air utilization unit 44 with multiple partitions. Figure 5As shown, when viewed from the width direction (x direction) of the nozzle 42, these multiple external air flow paths 45 are arranged in a manner that sandwiches the second flow path 43b. In addition, the external air flow paths 45 can be divided into multiple parts without partitions, and one external air utilization unit 44 corresponds to one external air flow path 45.

[0046] External air is connected to the outside air at both ends of flow path 45. For example... Figure 5 As shown, one end (+z direction side) of the external air flow path 45 is located near the nozzle 42. The other end (-z direction side) of the external air flow path 45 is located on the opposite side to one end (+z direction side) of the external air flow path 45. The shapes of both ends of the external air flow path 45 are triangular, but not limited to this. The shapes of both ends of the external air flow path 45 can be any shape such as circular, elliptical, polygonal, or rectangular.

[0047] exist Figure 6 middle, Figure 6 The figure above shows the fluid analysis results of the side nozzle involved in Embodiment 1. Figure 6 The figure below shows the fluid analysis results of the side nozzle according to Embodiment 2. The fluid analysis, for example, utilized computational fluid dynamics (CFD) analysis. Figure 6 The diagram shows the fluid analysis results of a cross-section of the side nozzle 40 as viewed from the length direction (x-direction) of the nozzle outlet 42. In the fluid analysis results, the distribution of flow velocity (in units such as m / s) is represented by differences in color.

[0048] like Figure 6 The fluid analysis results show that, by introducing gas into the side nozzle 40 and ejecting it from the outlet 42, external air is introduced into the external air flow path 45 from the other end (-z direction side). Furthermore, the external air introduced into the external air flow path 45 is ejected from one end (+z direction side). Thus, since a negative pressure is generated near the outlet 42 when the gas introduced into the side nozzle 40 is ejected, external air flow is generated in the external air flow path 45. The flow rate of the gas ejected from the outlet 42 increases due to the external air ejected from one end (+z direction side) of the external air flow path 45.

[0049] As explained above, according to the side nozzle 40 of this embodiment 2, the flow rate of the gas ejected from the nozzle outlet 42 is increased by the external air ejected from one end (+z direction side) of the external air flow path 45. Therefore, even if the supply of gas introduced into the side nozzle 40 is reduced, the side nozzle 40 can eject gas with a sufficient flow rate, thereby suppressing contamination of the protective glass.

[0050] Furthermore, the present invention is not limited to the above-described embodiments and can be appropriately modified without departing from the spirit of the invention.

[0051] Symbol Explanation

[0052] 1-Laser processing device, 10-Laser processing head, 11-House, 20-Laser oscillator, 30-Gas supply unit, 40-Side nozzle, 41-Inlet, 42-Outlet, 43-Flow path, 43a-First flow path, 43b-Second flow path, 44-External air utilization unit, 45-External air flow path, 50-Nose for processing point, AR1, AR2, AR3-Airflow, C-Block, LB-Laser beam, P-Pipe, W-Workpiece, W0-Processing point.

Claims

1. A laser processing apparatus, characterized in that, have: A laser processing head that directs a laser beam toward a workpiece; and A side nozzle, which, along the optical path from the laser processing head to the workpiece, ejects gas introduced from the inlet through a slit-shaped outlet. The gas is introduced into the inlet of the side nozzle from a direction inclined relative to the ejection direction of the gas from the outlet. The flow path guiding the gas introduced from the inlet to the outlet has a first flow path and a second flow path. The first flow path guides the gas from the inlet to the outlet along the length of the outlet, and the second flow path guides the gas exiting the first flow path to the outlet. The inner shape of the first flow path gradually narrows as it moves away from the inlet in the direction of gas introduction.

2. The laser processing apparatus according to claim 1, characterized in that, The width of the second flow path, when viewed from the length direction of the nozzle, first widens and then narrows as it moves toward the nozzle.

3. The laser processing apparatus according to claim 1 or 2, characterized in that, The side nozzle has multiple spray outlets. The plurality of said nozzles are arranged in one or more columns along the length of the nozzle.

4. The laser processing apparatus according to claim 3, characterized in that, The width of the second flow path, when viewed from the width direction of the nozzle, increases as it moves toward the nozzle.

5. The laser processing apparatus according to claim 4, characterized in that, The side nozzle has an external air flow path that is separate from the flow path. When viewed from the width direction of the nozzle, the external airflow path is arranged to sandwich the second flow path. The two ends of the external air flow path are connected to the external air. When the gas is ejected from the outlet of the side nozzle, the external air is ejected from one end of the external air flow path located near the outlet.

Images