JP7223640B2 - laser welder - Google Patents

Description

The present invention relates to a laser welder that selectively performs normal laser welding and weaving welding on metal workpieces.

Patent Document 1 discloses a laser welding machine that selectively performs normal laser welding and weaving welding. The prior art includes a weaving device for performing weaving welding, the weaving device forming part of the processing head of the laser welder. A brief description of the configuration of the weaving device according to the prior art is as follows.

The weaving device has a weaving housing, and a part of the optical path of the laser beam is formed inside the weaving housing. A swing arm is provided inside the weaving housing, and the swing arm is configured to be swingable about a swing axis on the base end side thereof. An annular support portion is formed on the tip side of the swing arm. A swing actuator for rotating the swing arm is provided on the outer wall of the weaving housing.

A main drive gear is rotatably provided on the optical path of the laser light inside the weaving housing, and the position of the main drive gear is shifted with respect to the swing arm in the optical axis direction of the laser light. A rotary actuator for rotating the main gear is provided on the outer wall of the weaving housing. A cylindrical driven rotator is rotatably provided inside the support portion of the swing arm, and an annular driven gear meshing with the main driving gear is formed on the outer peripheral portion of the driven rotator. there is

A glass plate as a transmission plate for decentering the optical axis of the laser light is integrally provided inside the driven rotating body. The glass plate is configured to move between a weaving position for weaving welding on the optical path of the laser beam and a retracted position retracted from the weaving position by the rocking motion of the rocking arm.

Therefore, by driving the swing actuator to swing the swing arm, the glass plate is moved from the retracted position to the weaving position. By rotating the main driving gear by driving the rotary actuator, the driven rotating body (driven gear) is rotated in conjunction with it, and the glass plate is rotated integrally with the driven rotating body. As a result, the optical axis of the laser beam can be eccentrically rotated to perform weaving welding with a wider welding width.

In addition to Patent Document 1, Patent Document 2 discloses a prior art related to the present invention.

JP 2015-58452 A JP 2013-39593 A

By the way, in recent years, the rotation speed of the driven rotor tends to increase as the output of the laser welding machine increases. In addition, when the rotational speed of the driven rotor increases, wear powder from between the main gear and the driven gear, grease (oil) from the bearing that supports the driven rotor, etc. flow into the internal space of the weaving housing as foreign matter. becomes easier. On the other hand, if foreign matter such as wear powder that flows into the inner space of the weaving housing adheres to the glass plate, defective weaving welding will be caused. In other words, there is a problem that it is difficult to stably perform weaving welding while increasing the output of the laser welding machine.

Therefore, in order to solve the above-mentioned problems, the present invention provides a laser welder having a novel configuration that can suppress the inflow of foreign matter into the internal space of the weaving housing even if the rotational speed of the driven rotor is increased. intended to provide

A laser welding machine according to an embodiment of the present invention includes a weaving housing in which a part of an optical path of a laser beam is formed, and a weaving housing provided inside the weaving housing that swings about a swing axis on the proximal end side. a rocking case configured to be able to rotate, a rocking actuator that rocks the rocking case, a main driving gear that is rotatably provided inside the base end side of the rocking case, and a main driving gear that rotates a rotary actuator; The laser welder according to the embodiment of the present invention is rotatably provided inside the tip side of the swing case, and the upper and lower parts face the outside of the swing case (the inner space side of the weaving housing). A cylindrical (annular) driven rotor that is open and has an annular driven gear that meshes with the main gear on its outer periphery; a transmission plate configured to move between a weaving position for performing weaving welding on the optical path of the laser beam and a retracted position retracted from the weaving position, and decentering the optical axis of the laser beam; there is

A laser welding machine according to an embodiment of the present invention includes a hollow first support member provided at the bottom or top of the base end side of the swing case and rotatably supported at the bottom or top of the weaving housing. and a hollow second support member provided at the upper or lower portion of the base end side of the swing case, positioned coaxially with the first support member, and rotatably supported at the upper or lower portion of the weaving housing. and may be provided. In this case, the output shaft of the swing actuator is connected to the first support member, the rotary shaft of the main driving gear is rotatably supported on the base end side of the swing case, and the second support member is coaxially connected. An output shaft of the rotary actuator may be connected to the rotary shaft through the upper part.

In an embodiment of the present invention, labyrinth structures are formed on the upper side and the lower side of the driven rotating body, respectively, for suppressing the outflow of foreign matter to the inner space side of the weaving housing (the outside of the swing case). good too.

According to an embodiment of the present invention, as described above, the swinging case is provided inside the weaving housing. The main drive gear is rotatably provided inside the base end side of the swing case. The cylindrical driven rotator is rotatably provided inside the tip side of the swing case, and the annular driven gear meshing with the main gear is formed on the outer peripheral portion of the driven rotator. Therefore, the main driving gear and the driven rotating body including the driven gear can be isolated from the internal space of the weaving housing by the swing case. As a result, even if the rotational speed of the driven rotor is increased, abrasion powder from between the main driving gear and the driven gear, grease from the bearing that supports the driven rotor, etc., may act as foreign matter inside the weaving housing. Inflow into the space can be suppressed.

According to the present invention, it is possible to stably perform weaving welding by sufficiently preventing foreign matter from adhering to the transmission plate while increasing the output of the laser welding machine.

FIG. 1 is a diagram showing part of a welding robot according to an embodiment of the present invention, and most of FIG. 1 is a cross-sectional view. FIG. 2 is a partial cross-sectional view of a processing head including a weaving device according to an embodiment of the invention. FIG. 3 is a cross-sectional view of the main part of the weaving device according to the embodiment of the present invention. FIG. 4A is a cross-sectional view taken along line IV-IV in FIG. 2, showing a state in which the glass plate is positioned at the weaving position. FIG. 4B is a cross-sectional view taken along line IV-IV in FIG. 2, showing a state in which the glass plate is positioned at the retracted position. FIG. 5 is an enlarged view of the arrowed portion V in FIG.

An embodiment of the present invention will be described with reference to FIGS. 1 to 5. FIG.

In the specification and claims of the present application, the term "provided" includes not only direct provision but also indirect provision via another member. "Upper, upper, upper end, or upper surface of the processing head" refers to the upper, upper, upper end, or upper surface when the nozzle of the processing head is oriented vertically downward. "The lower part, the lower side, the lower end, or the lower surface of the processing head" means the lower part, the lower side, the lower end, or the lower surface when the nozzle of the processing head is oriented vertically downward. In other words, the “vertical orientation of the processing head” is based on the state in which the nozzle of the processing head faces vertically downward. In the drawings, "U" indicates an upward direction, and "D" indicates a downward direction.

As shown in FIG. 1, a welding robot 10 according to an embodiment of the present invention is a laser welder that selectively performs ordinary laser welding and weaving welding on a metal workpiece W. As shown in FIG. The welding robot 10 includes an articulated robot arm 12 (only a portion of which is shown).At the tip of the robot arm 12, a processing head 14 for irradiating a workpiece W with a laser beam LB is connected to a connector 16. is provided through In addition, the configuration of the welding robot 10 excluding the processing head 14 is a known configuration as disclosed in Patent Document 2, and the detailed description of the configuration excluding the processing head 14 is omitted.

Next, the overall configuration of the processing head 14 will be described.

As shown in FIGS. 1 and 2, the machining head 14 has a cylindrical machining head main body 18 which is provided at the tip of the robot arm 12 via a connector 16 . The processing head 14 includes a support cylinder 20 disposed near the base end (upper end) of the processing head body 18. The support cylinder 20 is provided with a fiber holder 24 for holding a transmission fiber 22. ing. The transmission fiber 22 is optically connected to a laser oscillator (not shown) such as a fiber laser oscillator that oscillates laser light LB. In other words, the processing head 14 is optically connected to the laser oscillator via the transmission fiber 22 .

A nozzle 26 for irradiating the laser beam LB is provided at the tip (lower end) of the processing head body 18 . An annular upper lens holder 28 is provided in the processing head body 18 . A collimating lens 30 for collimating the laser beam LB emitted from the transmission fiber 22 is provided inside the upper lens holder 28 . A lower lens holder 32 is provided below the upper lens holder 28 inside the processing head body 18 . Inside the lower lens holder 32, a converging lens 34 for converging the collimated laser beam LB toward the work W is provided. Here, an optical path of the laser beam LB is formed from the exit end of the transmission fiber 22 inside the processing head 14 to the nozzle 26 .

The processing head 14 is equipped with a weaving device 36 for weaving the workpiece W. As shown in FIG. The weaving device 36 is arranged between the processing head main body 18 and the support cylinder 20 .

Next, a specific configuration of the weaving device 36 forming part of the processing head 14 will be described.

As shown in FIGS. 2 to 4B, the weaving device 36 includes a weaving housing 38 disposed between the processing head body 18 and the support tube 20. As shown in FIG. The weaving housing 38 integrally connects the processing head body 18 and the support tube 20 . An upper opening 38a is formed in the upper portion of the weaving housing 38, and a lower opening 38b is formed in the lower portion of the weaving housing 38 so as to align with the upper opening 38a. A peripheral edge of the upper opening 38 a of the weaving housing 38 is joined to one end (lower end) of the support tube 20 . A peripheral portion of the lower opening 38 b of the weaving housing 38 is joined to the base end (upper end) of the processing head body 18 . Inside the weaving housing 38, a part of the optical path of the laser beam LB is formed by the upper opening 38a and the lower opening 38b.

A closed swing case 40 is provided inside the weaving housing 38, and the swing case 40 extends in a direction perpendicular to the optical axis of the laser beam LB. An upper opening 40a is formed in the upper portion of the tip side of the swing case 40, and a lower opening portion 40b is formed in the lower portion of the tip side of the swing case 40 so as to be aligned with the upper opening portion 40a. ing.

A base end portion of a hollow (sleeve-shaped) first support member 42 is integrally provided at the bottom of the base end side of the swing case 40, and a tip end portion of the first support member 42 is a weaving housing. It is rotatably supported below 38 via bearings 44 . A base end portion of a hollow second support member 46 is integrally provided in the upper portion of the base end side of the swing case 40 , and the second support member 46 is coaxial with the first support member 42 . positioned. A distal end portion of the second support member 46 is rotatably supported on the upper portion of the weaving housing 38 via a bearing 48 . In other words, the swing case 40 is configured to be swingable about the swing axis on the base end side of the swing case 40 by the first support member 42, the second support member 46, and the like. A rocking motor 50 is provided as a rocking actuator for rocking the rocking case 40 at the lower part of the outer wall of the weaving housing 38 . An output shaft 52 of the swing motor 50 is coaxially and integrally connected to the first support member 42 by a connecting member 54 .

In addition, the tip of the first support member 42 is rotatably supported at the upper portion of the weaving housing 38 instead of the lower portion, and the tip portion of the second support member 46 is rotatably supported at the lower portion of the weaving housing 38 instead of the upper portion. It may be supported. In this case, the proximal end of the first support member 42 is rotatably supported on the upper portion of the weaving housing 38 and the distal end of the second support member 46 is rotatably supported on the lower portion of the weaving housing 38 .

A main driving gear 56 is rotatably provided inside the rocking case 40 on the base end side. A rotating shaft 58 of the main driving gear 56 is rotatably supported on the base end side of the swing case 40 via a plurality of bearings 60, and the rotating shaft 58 coaxially passes through the second support member 46. there is A rotary motor 62 is provided on the upper portion of the outer wall of the weaving housing 38 as a rotary actuator for rotating the main driving gear 56 . An output shaft 64 of the rotary motor 62 is coaxially and integrally connected to the rotary shaft 58 by a coupling 66 .

A cylindrical (annular) driven rotor 68 is rotatably provided inside the swing case 40 on the tip end side via a plurality of contact rubber seal type bearings 70 . The upper portion of the driven rotating body 68 is open from the upper opening 40a of the swing case 40 toward the inner space IS side of the weaving housing 38 (outside the swing case 40). The lower part of the driven rotating body 68 is open from the lower opening 40b of the swing case 40 toward the inner space IS of the weaving housing 38 . An annular driven gear 72 meshing with the main drive gear 56 is formed on the outer periphery of the driven rotor 68 , and the driven rotor 68 rotates in conjunction with the rotation of the main drive gear 56 .

A cylindrical glass holder 74 is integrally provided inside the driven rotating body 68 . Inside the glass holder 74, a glass plate 76 as a transmission plate for decentering the optical axis of the laser beam LB is provided via a glass retainer 78 and the like. In other words, the glass plate 76 is integrally provided inside the driven rotating body 68 via the glass holder 74 and the like. The glass plate 76 is inclined with respect to the optical axis of the laser beam LB and rotates together with the driven rotating body 68 .

If the glass plate 76 has a function of decentering the optical axis of the laser beam LB, instead of tilting the entire glass plate 76 with respect to the optical axis of the laser beam LB, the upper surface or the lower surface of the glass plate 76 is tilted. You may incline slightly with respect to the direction orthogonal to the optical axis of the laser beam LB. Further, instead of using the glass plate 76 as the transmission plate, another transmission plate made of a transparent material such as quartz or calcium fluoride may be used.

By swinging the swinging case 40, the glass plate 76 is moved to a weaving position (position shown in FIG. 4A) for performing weaving welding on the optical path of the laser beam LB, and a retracted position (shown in FIG. position). Here, when the glass plate 76 is positioned at the weaving position, the swinging case 40 abuts on a first stopper member (not shown) provided at an appropriate position inside the weaving housing 38 . When the glass plate 76 is at the retracted position, the rocking case 40 abuts on a second stopper member (not shown) provided at an appropriate position inside the weaving housing 38 .

As shown in FIGS. 3 and 5, an annular outer flange 80 is formed on the upper portion of the driven rotor 68 . An annular inner flange 82 is formed around the upper opening 40a of the swing case 40, and the inner flange 82 overlaps the upper side of the outer flange 80 with a small gap therebetween. A labyrinth structure 84 is formed between the outer flange 80 and the inner flange 82 to prevent foreign matter such as grease from flowing into the inner space IS side of the weaving housing 38 (outside the swing case 40). In other words, a labyrinth structure 84 that is a curved passage is formed on the upper side of the driven rotor 68 .

Similarly, an annular outer flange 86 is formed on the lower portion of the driven rotor 68 . An annular inner flange 88 is formed around the lower opening 40b of the swing case 40, and the inner flange 88 overlaps the lower side of the outer flange 86 with a small gap therebetween. A labyrinth structure 90 is formed between the outer flange 86 and the inner flange 88 to prevent foreign substances such as grease from flowing into the inner space IS of the weaving housing 38 . In other words, a labyrinth structure 90 that is a curved passage is formed on the lower side of the driven rotor 68 .

As shown in FIG. 3 , an annular air supply member 92 is provided inside the upper opening 38 a of the weaving housing 38 to supply purge air to the glass plate 76 .

Next, the effects of the embodiment of the present invention will be described.

By swinging the swing case 40 in one direction by driving the swing motor 50, the glass plate 76 is moved from the retracted position to the weaving position (see FIG. 4A). By rotating the main driving gear 56 by driving the rotary motor 62 , the driven rotating body 68 (driven gear 72 ) is interlocked and rotated, and the glass plate 76 is rotated integrally with the driven rotating body 68 . As a result, the optical axis of the laser beam LB emitted from the transmission fiber 22 can be eccentrically rotated to perform weaving welding with a wider welding width.

When normal laser welding is performed after weaving welding, the rocking case 40 is rocked in the other direction by driving the rocking motor 50 to move the glass plate 76 from the weaving position to the weaving position ( See Figure 4B).

According to the embodiment of the present invention, as described above, the closed swing case 40 is provided inside the weaving housing 38, and the main driving gear 56 is rotatable inside the base end side of the swing case 40. is provided. A cylindrical driven rotor 68 is rotatably provided inside the tip side of the swing case 40 , and an annular driven gear 72 meshing with the main drive gear 56 is formed on the outer periphery of the driven rotor 68 . Therefore, the driven rotating body 68 including the main driving gear 56 and the driven gear 72 can be isolated from the internal space IS of the weaving housing 38 by the swing case 40 . As a result, even if the rotational speed of the driven rotor 68 increases, abrasion powder from between the main gear 56 and the driven gear 72, grease from the contact rubber seal type bearing 70 that supports the driven rotor 68, etc. Inflow into the internal space IS of the weaving housing 38 can be suppressed. In particular, as described above, the driven rotor 68 is rotatably supported by a plurality of contact rubber seal type bearings 70, and the labyrinth structures 84 and 90 are formed on the upper and lower sides of the driven rotor 68, respectively. , even if the rotational speed of the driven rotor 68 increases, the inflow of foreign matter into the internal space IS of the weaving housing 38 can be sufficiently suppressed.

Therefore, according to the embodiment of the present invention, it is possible to stably perform weaving welding by sufficiently preventing adhesion of foreign matter to the glass plate 76 while increasing the output of the laser welding machine.

The present invention is not limited to the description of the above embodiment. For example, the weaving device 36 eccentrically rotates the optical axis of the laser beam LB before being collimated. Other various modes such as eccentrically rotating the optical axis of the LB are possible. And the scope of rights included in the present invention is not limited to the above-described embodiments.

10 Welding robot (laser welder)
12 robot arm 14 processing head 16 coupling tool 18 processing head body 20 support tube 22 transmission fiber 24 fiber holder 26 nozzle 28 upper lens holder 30 collimating lens 32 lower lens holder 34 focusing lens 36 weaving device 38 weaving housing 38a upper opening 38b lower Opening 40 Swing case 40a Upper opening 40b Lower opening 42 First support member 44 Bearing 46 Second support member 48 Bearing 50 Swing motor (swing actuator)
52 Output shaft 54 Connection member 56 Main driving gear 58 Rotating shaft 60 Bearing 62 Rotary motor (rotary actuator)
64 Output shaft 66 Coupling 68 Driven rotor 70 Contact rubber seal type bearing 72 Driven gear 74 Glass holder 76 Glass plate (Transmission plate)
78 Glass presser 80 Outer flange 82 Inner flange 84 Labyrinth structure 86 Outer flange 88 Inner flange 90 Labyrinth structure 92 Air supply member IS Internal space LB Laser beam W Work

Claims (4)

a weaving housing in which a part of the optical path of the laser light is formed;
a rocking case provided inside the weaving housing and configured to be rockable about a rocking axis on the base end side;
a swing actuator for swinging the swing case;
a main driving gear rotatably provided inside the base end side of the swing case;
a rotary actuator that rotates the main driving gear;
It is rotatably provided inside the front end side of the rocking case, the upper part and the lower part are opened toward the inner space side of the weaving housing, and the annular driven gear meshing with the main driving gear is formed on the outer peripheral part. a cylindrical driven rotating body;
Provided inside the driven rotating body, the swinging case moves between a weaving position for performing weaving welding on the optical path of the laser beam and a retracted position retracted from the weaving position. and a transmission plate configured to decenter the optical axis of the laser beam. a hollow first support member provided at the bottom or top of the base end side of the swing case and rotatably supported at the bottom or top of the weaving housing;
a hollow second support member provided at the upper or lower portion of the base end side of the swing case, positioned coaxially with the first support member, and rotatably supported at the upper or lower portion of the weaving housing; 2. The laser welder according to claim 1, comprising: an output shaft of the swing actuator is connected to the first support member;
a rotating shaft of the main driving gear is rotatably supported on the base end side of the swing case and coaxially penetrates the second support member;
3. The laser welder according to claim 2, wherein an output shaft of said rotary actuator is connected to said rotating shaft. 4. Labyrinth structures are formed on the upper side and the lower side of the driven rotating body respectively for suppressing the outflow of foreign matter to the inner space side of the weaving housing. The laser welder according to any one of 1.

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