welding head
The welding head's purge unit with balanced gas ejection sections addresses dust adhesion issues, enhancing dust suppression and maintaining laser light output for improved welding quality.
Patent Information
- Authority / Receiving Office
- JP · JP
- Patent Type
- Patents
- Current Assignee / Owner
- TOYOTA JIDOSHA KK
- Filing Date
- 2023-11-30
- Publication Date
- 2026-05-26
AI Technical Summary
Existing laser welding apparatuses face issues with dust adhesion to the protective glass, leading to reduced laser light output and poor welding quality due to ineffective dust suppression methods.
A welding head design featuring a purge unit with a flow path surrounded by gas ejection sections that direct gas inward and outward from the protective glass, enhancing dust suppression by creating balanced airflow to prevent adhesion.
The improved airflow design effectively suppresses dust adhesion to the protective glass, maintaining laser light output and ensuring consistent welding quality.
Smart Images
Figure 0007865322000001 
Figure 0007865322000002 
Figure 0007865322000003
Abstract
Description
Technical Field
[0001] This disclosure relates to a welding head of a laser welding apparatus.
Background Art
[0002] The welding head of a general laser welding apparatus includes a protective glass for preventing the intrusion of dust such as spatter and fume into an optical unit for guiding laser light to a welding object. At this time, when dust adheres to the protective glass, the output of the laser light decreases, resulting in poor welding.
[0003] Therefore, for example, the welding head of Patent Document 1 ejects gas in the direction of emission of the laser light between the protective glass and the welding object to suppress the adhesion of dust to the protective glass.
Prior Art Documents
Patent Documents
[0004]
Patent Document 1
Summary of the Invention
Problems to be Solved by the Invention
[0005] The applicant of the present application has found the following problems. The welding head of Patent Document 1 ejects gas in the direction of emission of the laser light between the protective glass and the welding object to suppress the adhesion of dust to the protective glass, but an improvement in the effect of suppressing the adhesion of dust to the protective glass is desired.
[0006] This disclosure has been made in view of such problems, and realizes a welding head that contributes to an improvement in the effect of suppressing the adhesion of dust to the protective glass.
Means for Solving the Problems
[0007] A welding head according to an aspect of the present disclosure is a welding head of a laser welding apparatus, An optical unit for guiding laser light to the object to be welded, A protective glass is positioned on the side of the optical unit facing the direction of laser beam emission to prevent dust from entering the interior of the optical unit. A purge unit is placed between the protective glass and the object to be welded, Equipped with, The aforementioned purge unit is A channel is arranged to surround the laser light emitted from the optical unit, A supply unit that supplies gas to the aforementioned flow path, A first ejection section that communicates with the aforementioned flow path and ejects the gas from the side of the protective glass toward the inside of the said flow path, A second ejection section is in communication with the aforementioned flow path and ejects the gas from the side of the object to be welded, on the inner side of the flow path and toward the side of the object to be welded, It has, The connection between the flow path and the supply unit is positioned between the first ejection unit and the second ejection unit in the direction of laser beam emission, and forms a branching unit that distributes the gas supplied from the supply unit to the side of the first ejection unit and the side of the second ejection unit. [Effects of the Invention]
[0008] According to this disclosure, it is possible to improve the effect of suppressing dust adhesion to protective glass. [Brief explanation of the drawing]
[0009] [Figure 1] (a) is a schematic perspective view of the welding head of Embodiment 1, and (b) is a cross-sectional view of (a) at the IB-IB position. [Figure 2] (a) is a perspective view showing the internal shape of the purge unit in the welding head of Embodiment 1, (b) is a view from the Z-axis+ side of the Y-axis- side portion of the internal structure of the purge unit of Embodiment 1, cut at the IB-IB position in Figure 1(a), and (c) is a view from the Y-axis+ side of the Y-axis- side portion of the internal structure of the purge unit of Embodiment 1, cut at the IB-IB position in Figure 1(a). [Figure 3] This figure shows the conical projection of the purge unit in the welding head of Embodiment 1. [Figure 4] (a) is a diagram showing the airflow analysis results of a comparative shape of a purge unit at a position corresponding to the IB-IB position in Figure 1(a), and (b) is a diagram showing the airflow analysis results of the purge unit of Embodiment 1 at the IB-IB position in Figure 1(a). [Figure 5] (a) is a view from the Z-axis+ side of the Y-axis-side portion of the internal structure of the purge unit of Embodiment 2, cut at a position corresponding to the IB-IB position in Figure 1(a); (b) is a view from the Y-axis+ side of the Y-axis-side portion of the internal structure of the purge unit of Embodiment 2, cut at a position corresponding to the IB-IB position in Figure 1(a); and (c) is a view from the Z-axis-side of the Y-axis-side portion of the internal structure of the purge unit of Embodiment 2, cut at a position corresponding to the IB-IB position in Figure 1(a). [Figure 6] The upper panel shows the results of airflow analysis at the penetration point and in the flow path of the purge unit when the purge unit of Embodiment 1 is used in a welding head, and the lower panel shows the results of airflow analysis at the penetration point and in the flow path of the purge unit when the purge unit of Embodiment 2 is used in a welding head. [Modes for carrying out the invention]
[0010] Specific embodiments applying this disclosure will be described in detail below with reference to the drawings. However, this disclosure is not limited to the following embodiments. Also, for clarity, the following description and drawings have been simplified as appropriate. Herein, for clarity, the following description will use a three-dimensional (XYZ) coordinate system.
[0011] <Embodiment 1> FIG. 1(a) is a perspective view schematically showing the welding head of the present embodiment, and FIG. 1(b) is a cross-sectional view taken at the IB-IB position of FIG. 1(a). As shown in FIGS. 1(a) and 1(b), for example, the welding head 1 of the present embodiment includes an optical unit (not shown), a protective glass 2, a purge unit 3, and a cross jet unit 4.
[0012] The optical unit includes lenses, mirrors, etc. so that the laser light incident from the optical fiber can be emitted toward the Z-axis side and irradiated onto the welding object. The protective glass 2 is fixed to the end portion on the Z-axis side of the optical unit in order to prevent the intrusion of dust such as spatter and fumes into the optical unit.
[0013] As shown in FIGS. 1(a) and 1(b), for example, the purge unit 3 is arranged to surround the laser light emitted from the optical unit on the Z-axis side with respect to the protective glass 2, and is configured to eject gas toward the radially inner side of the purge unit 3 in order to suppress the adhesion of dust to the protective glass 2.
[0014] As shown in FIGS. 1(a) and 1(b), for example, the purge unit 3 has a cylindrical shape having a substantially circular through-hole 3a extending in the Z-axis direction, and extends in the Z-axis direction. The diameter of the through-hole 3a on the Z-axis + side may be substantially equal to the diameter of the protective glass 2. And the diameter of the through-hole 3a may be reduced as it goes toward the Z-axis side.
[0015] FIG. 2(a) is a perspective view showing the internal shape of the purge unit in the welding head of the present embodiment, FIG. 2(b) is a view of the Y-axis - side portion of the internal structure of the purge unit of the present embodiment cut at the IB-IB position of FIG. 1(a) as seen from the Z-axis + side, and FIG. 2(c) is a view of the Y-axis - side portion of the internal structure of the purge unit of the present embodiment cut at the IB-IB position of FIG. 1(a) as seen from the Y-axis + side. FIG. 3 is a view showing the conical protrusion of the purge unit in the welding head of the present embodiment.
[0016] As shown in FIGS. 2(a) to 2(c), the purge unit 3 includes a flow path 5, a first ejection part 6, a second ejection part 7, a supply part 8, a dividing part 9, a first guiding part 10, a second guiding part 11, and a conical protrusion part 12.
[0017] As shown in FIG. 1(a), the flow path 5 is a cavity formed inside the purge unit 3 and is arranged in the circumferential direction of the purge unit 3. In FIG. 1(a), the gas flow path 5 and the like of the purge unit 3 are shown by solid lines.
[0018] As shown in FIG. 1(b), the first ejection part 6 ejects gas from the end on the +Z-axis side of the flow path 5 toward the inner side in the radial direction of the flow path 5. As shown in FIGS. 2(a) to 2(c), the first ejection part 6 penetrates the purge unit 3 from the flow path 5 toward the inner side in the radial direction of the flow path 5 and is arranged at the end on the +Z-axis side of the flow path 5.
[0019] As shown in FIG. 2(c), the first ejection part 6 is, for example, a substantially house-shaped shape (however, the shape is not limited) which is an example of a shape capable of ejecting gas when viewed from the radial direction of the flow path 5, and has an ejection port 6a for ejecting gas at the end on the inner side in the radial direction of the flow path 5 in the first ejection part 6. A plurality of such first ejection parts 6 are arranged at substantially equal intervals in the circumferential direction of the purge unit 3.
[0020] As shown in FIG. 1(b), the second ejection part 7 ejects gas from the end on the -Z-axis side of the flow path 5 toward the inner side in the radial direction of the flow path 5 and toward the -Z-axis side. As shown in FIGS. 1(b) and 2(c), the second ejection part 7 penetrates the purge unit 3 from the flow path 5 toward the inner side in the radial direction of the flow path 5 so as to incline toward the -Z-axis side as it goes toward the inner side in the radial direction of the flow path 5, and is arranged at the end on the -Z-axis side of the flow path 5.
[0021] As shown in Figure 2(c), the second ejection section 7 has a slit shape that is substantially continuous in the circumferential direction of the flow path 5, and is equipped with an outlet 7a for ejecting gas at the radially inner end of the flow path 5 in the second ejection section 7. At this time, although the detailed function will be described later, it is preferable that the total area of the outlet 6a of the first ejection section 6 be larger than the total area of the outlet 7a of the second ejection section 7.
[0022] The supply unit 8 supplies gas to the flow path 5. As shown in Figure 2(a), for example, the supply unit 8 penetrates the flow path 5 radially outward from the flow path 5 between the first ejection unit 6 and the second ejection unit 7 in the Z-axis direction.
[0023] As shown in Figure 2(a), the supply units 8 are arranged at three or more locations (four locations in Figure 2(a)) at approximately equal intervals in the circumferential direction of the flow path 5. As shown in Figure 1(b), gas supply pipes 13 are connected to the radially outer ends of the flow path 5 in these supply units 8.
[0024] At this time, the connection point 14 between the flow path 5 and the supply unit 8 forms a branching point that distributes the gas to the Z-axis+ side, which is the side of the first ejection unit 6, and the Z-axis- side, which is the side of the second ejection unit 7. Here, although the detailed function will be described later, it is preferable that the supply unit 8 be located on the side of the first ejection unit 6 between the first ejection unit 6 and the second ejection unit 7 in the Z-axis direction.
[0025] As shown in Figure 2(a), the dividing section 9 divides the flow path 5 into independent chambers 15 where each supply unit 8 is located approximately in the center of the flow path 5 in the circumferential direction, when viewed from the Z-axis direction. In other words, the dividing section 9 is located approximately in the center of adjacent supply units 8 in the circumferential direction of the flow path 5, when viewed from the Z-axis direction.
[0026] Therefore, for example, in the illustrated example in Figure 2(a), the dividing sections 9 are arranged at four locations at approximately equal intervals in the circumferential direction of the flow path 5 when viewed from the Z-axis direction, dividing the flow path 5 into four independent chambers 15. The dividing section 9 comprises, for example, a first dividing wall 9a and a second dividing wall 9b.
[0027] The first dividing wall 9a, whose detailed shape will be described later, extends in the Z-axis direction as shown in Figure 2(a), and is formed in the purge unit 3 so as to reach from the Z-+ side end of the flow path 5 to the vicinity of the Z-- side end. As a result, a slit is formed in the flow path 5 by the first dividing wall 9a.
[0028] The second dividing wall 9b extends in the Z-axis direction within the flow channel 5, as shown in Figure 2(a), for example, and reaches from the Z-axis-side end of the first dividing wall 9a to the Z-axis-side end of the flow channel 5. The shape of the second dividing wall 9b can be any shape that can divide the flow channel 5.
[0029] The first guide section 10 guides the gas supplied to the flow path 5 to the Z-axis+ side, which is the side of the first ejection section 6. The first guide section 10 is formed on both sides of the flow path 5 in the circumferential direction of the first dividing wall 9a, as shown in Figure 2(a), and is an inclined section (which may also be a curved section) that widens in the circumferential direction of the flow path 5 as it approaches the Z-axis- side.
[0030] The second guide unit 11 guides the gas supplied to the flow path 5 to the Z-axis side, which is the side of the second ejection unit 7. The second guide unit 11 is positioned on the Z-axis side relative to the first guide unit 10, for example, as shown in Figure 2(a).
[0031] The second guide portion 11 is formed on both sides of the flow path 5 in the circumferential direction of the first dividing wall 9a, as shown in Figure 2(a), and is an inclined portion (which may also be a curved portion) that widens in the circumferential direction of the flow path 5 as it approaches the Z-axis+ side.
[0032] This allows the gas supplied to each independent chamber 15 of the flow path 5 to be smoothly guided to the first ejection section 6 and the second ejection section 7, respectively. In this case, it is preferable that the first guide section 10 and the second guide section 11 form a roughly diamond-shaped section in the first dividing wall 9a, for example.
[0033] Here, the first guide unit 10 and the second guide unit 11 can be arranged on the Z-axis+ side relative to the supply unit 8 in the Z-axis direction, for example, as shown in Figure 2(a). However, the arrangement and shape of the first guide unit 10 and the second guide unit 11 are not limited, as long as they can guide the gas to the side of the first ejection unit 6 and the side of the second ejection unit 7, respectively.
[0034] As shown in Figure 3, the conical projection 12 protrudes from the radially inner surface of the flow path 5 in the purge unit 3 toward the radially outer surface of the flow path 5, and is positioned to face the supply unit 8 in the radial direction of the flow path 5. The diameter of the conical projection 12 decreases as it extends toward the radially outer surface of the flow path 5. This allows the gas supplied to each independent chamber 15 of the flow path 5 via the supply unit 8 to diffuse smoothly and radially.
[0035] The Z-axis positive end of the purge unit 3 is fixed to the Z-axis negative end of the optical unit via the protective glass 2, with the center of the penetration portion 3a of the purge unit 3 positioned on the optical path of the laser beam when viewed from the Z-axis direction, and the flow path 5 of the purge unit 3 positioned to surround the protective glass 2.
[0036] The cross-jet unit 4 is configured to eject gas, for example, toward the X-axis + side, in order to suppress dust adhesion to the protective glass 2. Here, since the cross-jet unit 4 is not an essential part of this disclosure, only a brief explanation will be given.
[0037] The cross-jet unit 4 includes a nozzle 16 and a flow section 17, as shown in Figures 1(a) and 1(b), for example. The nozzle 16 is positioned to eject gas toward the X-axis + side. In Figure 1(a), the gas flow path of the nozzle 16 is shown by a solid line.
[0038] The flow section 17 is, for example, as shown in Figures 1(a) and 1(b), roughly shaped like a shovel extending in the X-axis direction, and when viewed from the Y-axis direction, the portion of the flow section 17 on the X-axis+ side is tapered, inclining toward the Z-axis+ side as it moves toward the X-axis+ side.
[0039] The flow section 17 includes, for example, a passage section 17a through which the laser beam passes, an intake section 17b for taking in outside air, and an exhaust section 17c for discharging the gas inside the flow section 17, as shown in Figure 1(b). A nozzle 16 is fixed to the portion of the flow section 17 that is on the X-axis side relative to the passage section 17a.
[0040] The Z-axis positive end of the cross jet unit 4 is fixed to the Z-axis negative end of the purge unit 3, for example, as shown in Figures 1(a) and 1(b), with the center of the passage portion 17a of the flow portion 17 positioned on the optical path of the laser beam when viewed from the Z-axis direction.
[0041] Such a cross-jet unit 4 is configured to draw in outside air from the intake section 17b into the flow section 17, while simultaneously ejecting gas from the nozzle 16 toward the X-axis + side, thereby discharging dust that has entered the flow section 17 from the discharge section 17c. However, the configuration of the cross-jet unit 4 is not limited; any configuration that can eject gas in a manner that crosses the laser beam is acceptable.
[0042] Next, the process by which the welding head 1 of this embodiment welds an object will be described. When welding an object with the welding head 1, for example, the welding head 1 moves toward the Y-axis while emitting laser light from the optical unit and irradiating the object to be welded, thereby welding the object.
[0043] At this time, dust enters the interior of the flow section 17 from the passage section 17a and intake section 17b of the flow section 17, but the purge unit 3 sprays gas radially inward into the flow path 5, and the cross jet unit 4 sprays gas toward the X-axis + side, thereby suppressing the dust from adhering to the protective glass 2.
[0044] Next, a comparison of the airflow analysis results of the purge unit 3 in the welding head 1 of this embodiment with the airflow analysis results of a purge unit of a comparative shape will be explained. Figure 4(a) shows the airflow analysis results of a purge unit of a comparative shape at a position corresponding to the IB-IB position in Figure 1(a), and Figure 4(b) shows the airflow analysis results of the purge unit of this embodiment at the IB-IB position in Figure 1(a).
[0045] Here, the comparative shape of the purge unit 101 is configured such that multiple ejection nozzles 102 that eject gas on the Z-axis+ side are arranged at equal intervals in the circumferential direction of the purge unit 101. When such a comparative shape of the purge unit 101 is used in the welding head 100, as shown in Figure 4(a), a vortex V is generated within the purge unit 101 by the airflow A1 directed toward the Z-axis+ side due to the gas ejected from the ejection nozzles 102 toward the Z-axis+ side, and by the airflow A2 directed toward the Z-axis- side when the gas comes into contact with the protective glass 2.
[0046] Therefore, when a purge unit 101 of the comparative shape is used in the welding head 100, dust is easily drawn into the penetration portion 101a of the purge unit 101 from the cross jet unit 103, and the dust that enters the penetration portion 101a of the purge unit 101 cannot be properly discharged.
[0047] On the other hand, when the purge unit 3 of this embodiment is used on the welding head 1, as shown in Figure 4(b), the gas ejected from the first ejection ports 6 facing each other in the radial direction of the flow path 5 collides approximately in the center of the penetration port 3a of the purge unit 3, splitting into a first airflow A11 directed toward the Z-axis+ side and an airflow A12 directed toward the Z-axis- side. The first airflow A11 directed toward the Z-axis+ side removes dust adhering to the protective glass 2, while the airflow A12 directed toward the Z-axis- side discharges the dust from the penetration port 3a of the purge unit 3.
[0048] At this time, as shown in Figure 4(b), the airflow A12 directed toward the Z-axis decreases the air pressure at the penetration 3a of the purge unit 3, generating a second airflow A13 directed toward the Z-axis+. However, since the gas is ejected from the second ejection port 7 radially inward of the flow path 5 and toward the Z-axis-, the intrusion of dust into the penetration 3a of the purge unit 3 can be suppressed.
[0049] Therefore, when the purge unit 3 of this embodiment is used on the welding head 1, compared to when the purge unit 101 of the comparative shape is used on the welding head 100, the intrusion of dust into the penetration portion 3a of the purge unit 3 can be suppressed, and this contributes to improving the effect of suppressing dust adhesion to the protective glass 2.
[0050] As described above, the welding head 1 of this embodiment has a purge unit 3 that, in addition to the first ejection part 6, has a second ejection part 7 that ejects gas radially inward into the flow path 5 and toward the Z-axis. Therefore, dust can be suppressed from entering the penetration part 3a of the purge unit 3, and for example, compared to the case where a purge unit 101 of a comparative shape is used in the welding head 100, the effect of suppressing dust adhesion to the protective glass 2 is higher.
[0051] Furthermore, in the welding head 1 of this embodiment, since the flow path 5 is divided by the dividing portion 9 into independent chambers 15 located approximately in the center of the flow path 5 in the circumferential direction, gases collide in the portion of the flow path 5 between adjacent supply portions 8 in the circumferential direction, and the gas ejected from the first ejection portion 6 near the collision portion is suppressed from being ejected more strongly than the gas ejected from other first ejection portions 6.
[0052] Therefore, the strength of the gas ejected from the first ejection port 6 can be made nearly uniform, and turbulence in the airflow at the penetration port 3a of the purge unit 3 can be suppressed. This suppresses uneven adhesion of dust to the protective glass 2.
[0053] Furthermore, in the welding head 1 of this embodiment, since the purge unit 3 is equipped with a first guide section 10, a second guide section 11, and a conical projection 12, the gas can be smoothly guided to the first ejection section 6 and the second ejection section 7, respectively, and a decrease in the gas flow velocity can be suppressed. As a result, the effect of suppressing the intrusion of dust into the penetration section 3a of the purge unit 3 and the effect of suppressing the adhesion of dust to the protective glass 2 can be improved.
[0054] Since gas flows to the side from which it is more easily ejected, in the welding head 1 of this embodiment, if the total area of the nozzle 6a of the first ejection part 6 is larger than the total area of the nozzle 7a of the second ejection part 7, the flow rate of gas ejected from the first ejection part 6 can be made larger than the flow rate of gas ejected from the second ejection part 7.
[0055] Furthermore, in the welding head 1 of this embodiment, if the supply unit 8 is located on the side of the first ejection unit 6 between the first ejection unit 6 and the second ejection unit 7 in the Z-axis direction, the flow rate of gas ejected from the first ejection unit 6 can be made greater than the flow rate of gas ejected from the second ejection unit 7.
[0056] Therefore, the first airflow A11 directed toward the Z-axis+ side and the airflow A12 directed toward the Z-axis- side in the gas ejected from the first ejection part 6 can be strengthened, thereby improving the effect of suppressing the intrusion of dust into the penetration part 3a of the purge unit 3 and the effect of suppressing the adhesion of dust to the protective glass 2.
[0057] In these cases, it is preferable to distribute the gas supplied from the supply unit 8 to the first discharge unit 6 and the second discharge unit 7 so that the flow rate of gas discharged from the first discharge unit 6 is greater than the flow rate of gas discharged from the second discharge unit 7, while suppressing the entry of dust into the penetration 3a of the purge unit 3 by the gas discharged from the second discharge unit 7.
[0058] <Embodiment 2> Figure 5(a) is a view from the Z-axis+ side of the Y-axis-side portion of the internal structure of the purge unit of this embodiment, cut at a position corresponding to the IB-IB position in Figure 1(a); Figure 5(b) is a view from the Y-axis+ side of the Y-axis-side portion of the internal structure of the purge unit of this embodiment, cut at a position corresponding to the IB-IB position in Figure 1(a); and Figure 5(c) is a view from the Z-axis-side of the Y-axis-side portion of the internal structure of the purge unit of this embodiment, cut at a position corresponding to the IB-IB position in Figure 1(a).
[0059] The upper part of Figure 6 shows the results of airflow analysis at the penetration point of the purge unit and in the flow path when the purge unit of Embodiment 1 is used in a welding head, and the lower part of Figure 6 shows the results of airflow analysis at the penetration point of the purge unit and in the flow path when the purge unit of this embodiment is used in a welding head.
[0060] As shown in the upper and lower sections of Figure 6, the purge unit 31 of this embodiment has substantially the same configuration as the purge unit 3 of Embodiment 1. Therefore, redundant explanations will be omitted, and the same reference numerals will be used for the same elements. The purge unit 31 is configured to generate a swirling flow at the penetration portion 31a.
[0061] In detail, the first ejection section 32 penetrates the flow path 5 radially inward, from the flow path 5, as shown in Figures 5(a) and 5(b), for example, when viewed from the Z-axis+ side, the purge unit 31 is tilted counterclockwise as it moves radially inward with respect to the radial direction of the flow path 5.
[0062] Furthermore, as shown in Figures 5(b) and 5(c), the purge unit 31 has inclined fins 34 positioned directly in front of the second ejection section 33 in the flow path 5. The inclined fins 34 are positioned within the flow path 5 of the purge unit 31 and, when viewed from the Z-axis+ side, are inclined counterclockwise as they move radially inward relative to the radial direction of the flow path 5. Multiple inclined fins 34 are arranged at approximately equal intervals in the circumferential direction of the flow path 5.
[0063] When such a purge unit 31 is used in a welding head, as shown in the airflow analysis results in the lower left of Figure 6, it can be seen that, compared to the airflow analysis results in the upper left of Figure 6 when the purge unit 3 of Embodiment 1 is used in the welding head 1, the coriander effect causes the swirling flow at the penetration portion 31a of the purge unit 31 to entrain the surrounding gas, increasing the flow velocity.
[0064] Furthermore, when the purge unit 31 of this embodiment is used in a welding head, the inclined fins 34 in the flow path 5 create resistance to the gas flow. As shown in the airflow analysis results in the lower right of Figure 6, the gas supplied from the supply unit 8 is more easily guided to the first ejection unit 32 compared to the airflow analysis results in the upper right of Figure 6 when the purge unit 3 of Embodiment 1 is used in the welding head 1.
[0065] Therefore, when the purge unit 31 of this embodiment is used in a welding head, the effect of suppressing the intrusion of dust into the penetration portion 31a of the purge unit 31 and the effect of suppressing the adhesion of dust to the protective glass 2 can be improved compared to when the purge unit 3 of Embodiment 1 is used in a welding head 1.
[0066] Note that the inclination directions of the first ejection section 32 and the inclined fin 34 in this embodiment are illustrative and may be reversed. In short, it is sufficient that the inclination direction of the first ejection section 32 and the inclined fin 34 are the same when viewed from the Z-axis direction.
[0067] This disclosure is not limited to the embodiments described above, and may be modified as appropriate without departing from the spirit of the invention. For example, the welding head 1 in the above embodiment includes a cross-jet unit 4, but this may be omitted. For example, the configuration of the purge units 3 and 31 in the above embodiment is illustrative, and it is sufficient to include at least a first ejection part that ejects gas from the Z-axis+ end of the flow path 5 toward the radially inward direction of the flow path 5, and a second ejection part that ejects gas from the Z-axis- end of the flow path 5 toward the radially inward direction of the flow path 5 and toward the Z-axis- side. [Explanation of Symbols]
[0068] 1 Welding head 2. Protective glass 3. Purge unit, 3a. Penetration section 4 Cross Jet Unit 5 channels 6 First ejection section, 6a Nozzle 7 Second spout, 7a spout 8 Supply section 9 Divided section, 9a First dividing wall, 9b Second dividing wall 10 First guidance section 11. Second guidance section 12 Conical projection 13 Supply pipe 14 Connection part 15 Separate room 16 nozzles 17 Distribution section, 17a Passage section, 17b Intake section, 17c Discharge section 31 Purge unit, 31a Through section 32 First ejection section 33 Second ejection section 34 angled fins 100 welding heads 101 Purge unit, 101a Penetration section 102 Spout part 103 Cross Jet Unit A1 Airflow directed towards the Z-axis + side A2 Airflow directed toward the Z-axis side A11 First airflow directed towards the Z-axis + side A12 Airflow directed toward the Z-axis side A13 Second airflow directed towards the Z-axis + side V vortex
Claims
1. A welding head for a laser welding device, An optical unit for guiding laser light to the object to be welded, A protective glass is positioned on the side of the optical unit facing the direction of laser beam emission to prevent dust from entering the interior of the optical unit. A purge unit is placed between the protective glass and the object to be welded, Equipped with, The aforementioned purge unit is A channel is arranged to surround the laser light emitted from the optical unit, A supply unit that supplies gas to the aforementioned flow path, A first ejection section that communicates with the aforementioned flow path and ejects the gas from the side of the protective glass toward the inside of the said flow path, A second ejection section is in communication with the aforementioned flow path and ejects the gas from the side of the object to be welded, on the inner side of the flow path and toward the side of the object to be welded, It has, The connection between the flow path and the supply unit is located between the first ejection unit and the second ejection unit in the direction of laser beam emission, and forms a branching unit that distributes the gas supplied from the supply unit to the side of the first ejection unit and the side of the second ejection unit, in the welding head.
2. Three or more of the supply units are arranged at equal intervals in the circumferential direction of the flow path. The aforementioned purge unit is Viewed in the direction of the laser beam emission, each of the supply units is located in an independent chamber in the center, with a dividing section that divides the flow path, A first guide unit that guides the gas supplied to the flow path toward the first ejection unit, A second guide unit that guides the gas supplied to the flow path toward the second ejection unit, A welding head according to claim 1, comprising:
3. The welding head according to claim 1 or 2, wherein the purge unit comprises a conical projection that protrudes toward the side of the supply unit from the portion of the flow path facing the supply unit.
4. The welding head according to claim 1 or 2, wherein the total area of the gas outlets in the first ejection section is larger than the total area of the gas outlets in the second ejection section.
5. The first ejection section is arranged such that, when viewed in the direction of the laser beam emission, the gas is ejected at an angle with respect to the radial direction of the flow path. The welding head according to claim 1 or 2, wherein the purge unit includes an inclined fin positioned directly in front of the second ejection part such that, when viewed in the direction of emission of the laser beam, gas is ejected from the second ejection part in an inclined direction equal to the direction of ejection of gas ejected from the first ejection part.