JP4127614B2 - Laser welding apparatus and welding method - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a laser welding apparatus and a welding method, and more particularly, to a laser welding apparatus and a welding method for adjusting a filler wire and / or a laser projecting portion to an appropriate position.
[0002]
[Prior art]
2. Description of the Related Art Conventionally, processing using a laser beam has been widely adopted, and it is used for welding a frame or a sheet metal in a vehicle manufacturing process. At this time, the filler wire is supplied to the welding pond at the time of welding for the purpose of filling the gap at the time of joining or butt welding of a material having a high melting point or improving the welding strength, It is performed to melt and weld together with the member to be welded.
[0003]
By the way, if the filler wire is fed in a state shifted from the molten pool, the gap toughness that fills the sheet metal gap is lowered, the posture toughness that the filler wire is uniformly piled up, and the filler wire and the welded wire are welded. Inconvenience such as generation of vibration due to sliding with the member occurs.
[0004]
Laser welding has a higher welding speed than TIG welding, and the laser beam diameter is generally as small as 0.6 [mm]. Therefore, the small-diameter molten pool moves at a high speed, and it is necessary to feed the filler wire with high control accuracy.
[0005]
Further, in order to obtain high energy, the focal length of the laser beam needs to be adjusted accurately with respect to the member to be welded.
[0006]
[Problems to be solved by the invention]
In order to accurately feed the filler wire, an image is taken while moving the camera along the filler wire to detect the position of the filler wire (see Japanese Patent No. 2941588), and the tip of the filler wire is imaged. A technique (see Japanese Patent Application Laid-Open No. 2001-179471) for detecting the amount and direction of feeding a filler wire from the obtained image has been proposed.
[0007]
However, in these conventional technologies, only the position of the filler wire in the horizontal plane can be detected, and the height and angle cannot be detected. Therefore, when welding various types of sheet metal having different thicknesses, the welding operation must be interrupted each time and manually adjusted while visually checking the height and angle.
[0008]
Further, the conventional technique detects only the position of the filler wire, and cannot detect the adjustment of the focal length of the laser beam. Therefore, when welding various types of sheet metal having different thicknesses, it is necessary to provide a device for detecting the focal length separately from the wire position detecting device.
[0009]
The present invention has been made in consideration of such problems, and detects the horizontal position, height and / or angle of the filler wire to be fed when laser welding is performed, so that the filler wire is moved to the specified position and / or Alternatively, it is an object to provide a laser welding apparatus and a welding method that can be adjusted to a specified angle.
[0010]
Another object of the present invention is to enable detection of the height of the light projecting unit in order to adjust the height of the light projecting unit of the laser in accordance with the focal length.
[0011]
[Means for Solving the Problems]
The laser welding apparatus according to the present invention is A laser is applied to the welding irradiation part of the member to be welded from the first direction, and a filler wire is applied to the welding irradiation part from a second direction different from the first direction. Send Above In a laser welding apparatus for welding the member to be welded by melting the filler wire by a laser, The filler wire has a width wider than the full width of the filler wire and a predetermined thickness. The filler wire is irradiated from a third direction different from the first direction and the second direction to the filler wire. Crossing Do measurement With the beam, It is an irradiation location of the measurement beam on the filler wire from at least a fourth direction different from the second direction and the third direction. A camera for imaging the measurement irradiation unit; An irradiation angle of the measurement beam; and Images captured by the camera In Of the irradiation unit for measurement position Based on the filler wire At least in the height direction A position calculation unit that calculates a position, and the position calculated by the position calculation unit is a specified position. Place Standard tolerance position When out of range, allow the filler wire to allow position And a wire position adjusting unit that adjusts movement within the range.
[0012]
in this way do it The filler wire position can be calculated, and the filler wire position is the specified position. Place When they are out of alignment, the position can be adjusted.
[0013]
in this case, The measurement beam is a parallel beam having a constant thickness, and the position calculation unit calculates the angle of the filler wire based on the thickness of the measurement beam and the shape of the measurement irradiation unit in the image, The wire position adjustment unit moves and adjusts the filler wire within the allowable angle range when the angle calculated by the position calculation unit is outside the allowable angle range based on a specified angle. Also good.
[0015]
further, The respective projecting portions of the laser and the measurement beam have a fixed relative position, and at least a part of the remaining portion of the measurement beam that irradiates the measurement irradiation portion of the filler wire is welded. Irradiate the member, The camera is measurement A welded member irradiation portion of the welded member irradiated by a beam and a welding irradiation portion irradiated by the laser Within one image Image In the one image The distance between the welded part irradiation part and the welding irradiation part And irradiation angle of the measurement beam A laser height calculation unit that calculates a height of the laser projecting unit with respect to the welding irradiation unit, and a height calculated by the laser height calculation unit is an allowable height based on a specified height When out of range, the laser and the measurement You may have the advance / retreat drive part which carries out the movement advance adjustment of each light projection part of a beam integrally with respect to the said welding irradiation part, and moves and adjusts in the said allowable height.
[0016]
Furthermore, said measurement The beam may be generated by deflecting part of the laser.
[0017]
Above measurement The beam is in a line shape It consists of two parallel beams Also good.
[0021]
The laser welding method according to the present invention includes: A laser is applied to the welding irradiation part of the member to be welded from the first direction, and a filler wire is applied to the welding irradiation part from a second direction different from the first direction. Send Above In a laser welding method for welding the member to be welded by melting the filler wire by a laser, A measurement beam having a width wider than the full width of the filler wire is applied to a middle portion of the filler wire from a third direction different from the first direction and the second direction, and intersects the filler wire. Steps, It is an irradiation location of the measurement beam on the filler wire from at least a fourth direction different from the second direction and the third direction. Imaging a measurement irradiation unit with a camera; An irradiation angle of the measurement beam; and Images captured by the camera In Of the irradiation unit for measurement position Based on the filler wire At least in the height direction A step of calculating a position, and the calculated position of the filler wire is a specified position; Place Standard tolerance position When out of range, allow the filler wire to allow position And a step of adjusting the movement within the range.
[0023]
DETAILED DESCRIPTION OF THE INVENTION
Embodiments of a laser welding apparatus and a welding method according to the present invention will be described below with reference to FIGS.
[0024]
First, a laser welding apparatus 10 according to the first embodiment and a welding method using the laser welding apparatus 10 will be described with reference to FIGS.
[0025]
The laser welding apparatus 10 basically deflects a part of a laser used for welding to form an auxiliary beam and irradiates the filler wire with the auxiliary beam. The irradiation unit is imaged by a camera, and the position of the filler wire is obtained from the position, shape and area of the irradiation unit, and the height of the laser projection unit is calculated.
[0026]
Hereinafter, for convenience of description, three-dimensional coordinates for specifying a direction are set, and directions indicated by arrows X and Y in FIG. 1 are set as an X axis and a Y axis, respectively. The Y axis represents the height relative to the steel plates W1, W2, and the Y axis direction is also referred to as the height direction. Further, the direction perpendicular to the paper surface of FIG. 1 is taken as the Z axis (see FIG. 3). Furthermore, a plane expressed by the X axis and the Z axis, that is, a plane parallel to the surfaces of the steel plates W1 and W2 is defined as a horizontal plane.
[0027]
As shown in FIG. 1, the laser welding apparatus 10 irradiates the steel plates W1 and W2 with the auxiliary beam L1 and irradiates the laser beam L2 onto the welding portion (welding irradiation portion) P where the steel plates W1 and W2 are abutted. A laser irradiation mechanism 12 for welding the steel plates W1 and W2, a robot arm 14 for moving the auxiliary beam L1 and the laser beam L2 in the welding direction in synchronization with each other, and a control mechanism for controlling the entire laser welding apparatus 10. 16.
[0028]
A support bracket 18 is fixed to the robot arm 14, and the support bracket 18 includes an upper surface plate 20 and a side surface plate 22 extending in a longitudinal direction substantially orthogonal to the upper surface plate 20. A first actuator 24 such as a cylinder piston mechanism is attached to the upper surface plate 20, and a guide member 28 that slidably supports an advancing / retreating drive unit 30 described later is attached to the inner surface 22 a of the side plate 22. ing.
[0029]
The advancing / retreating drive unit 30 having one side surface slidably supported by the guide member 28 is screwed to the rod 32 of the first actuator 24 via a nut 34 on one side. Accordingly, the advance / retreat drive unit 30 is provided so as to be able to reciprocate along the Y-axis direction while being guided by the guide member 28 and driven by the first actuator 24.
[0030]
A base plate 36 is fixed to the other side surface of the advance / retreat drive unit 30, and a laser irradiation mechanism 12 that irradiates the auxiliary beam L 1 and the laser beam L 2 is attached to the base plate 36.
[0031]
The laser irradiation mechanism 12 includes a casing 38 fixed to the base plate 36, and an optical fiber 42 for introducing a laser beam L from the laser oscillator 40 into the casing 38 is connected to an upper end portion of the casing 38. Yes. Further, in order to protect the laser irradiation mechanism 12 from spatter scattering during welding, a cylindrical shield nozzle 44 having a diameter reduced downward is provided at the lower end portion of the casing 38.
[0032]
On the optical axis O of the laser beam L derived from the optical fiber 42, a collimator lens 46 and a condensing lens 48 are disposed along the Y-axis direction, and the collimator lens 46 and the condensing lens 48 are In the meantime, the deflection lens 50 is disposed via the advance / retreat means 52 and the rotation means 54.
[0033]
Further, on the optical axis O, between the collimator lens 46 and the condenser lens 48, a field of view (see the broken line 55) that can be seen from the opening of the shield nozzle 44 is perpendicular to the optical axis O. A first right-angle prism 56 to be refracted is disposed. The image refracted by the first right-angle prism 56 is refracted again by the second right-angle prism 58 to become a parallel light beam with respect to the optical axis O, and is imaged by a camera 60 (such as a CMOS camera or a CCD camera). An image captured by the camera 60 is supplied to the control mechanism 16.
[0034]
Thereby, the camera 60 can image the welding part P from right above, and can verify the periphery of the welding part P in detail. Moreover, since the obtained image is an image on the horizontal plane, that is, the XZ plane, it is suitable for analysis processing.
[0035]
Note that the second prism 58 can be omitted if the camera 60 is positioned at a right angle to the optical axis O and disposed at the position of the second prism 58. Further, both the first prism 56 and the second prism 58 may be omitted, and the camera 60 may be arranged and imaged at an arbitrary position where the welded part P and its peripheral part can be faced.
[0036]
As shown in FIGS. 1 and 2, the advance / retreat means 52 includes a second actuator 64 fixed to the rotating member 62, and a deflection is provided at the tip of a rod 66 protruding from the second actuator 64 toward the optical axis O side. The lens 50 is fixed. The rotating member 62 is rotatably supported with respect to the casing 38 via a bearing 68. The deflection lens 50 divides the laser beam L into the auxiliary beam L1 and the laser beam L2, and the advance / retreat means 52 has a function of adjusting the output ratio of the auxiliary beam L1 and the laser beam L2, and the auxiliary beam L1. Is adjusted to a weak output capable of irradiating a predetermined position within the imaging range to such an extent that the camera 60 can take an image. On the other hand, the laser beam L2 is adjusted to a large output that can be welded by once melting the steel plates W1 and W2.
[0037]
By using the polarizing lens 50 in this way, two beams of the auxiliary beam L1 and the laser beam L2 can be obtained even if the laser supply source is only the laser oscillator 40, and the auxiliary beam can be obtained by the advance / retreat means 52. The output ratio between L1 and laser beam L2 can be adjusted. Further, the auxiliary beam L <b> 1 can have an arbitrary shape depending on the characteristics of the polarizing lens 50.
[0038]
As shown in FIG. 3, the auxiliary beam L1 is substantially parallel light due to the characteristics of the deflection lens 50 and the condenser lens 48, and is irradiated as a line beam having a width T1. The irradiation direction of the auxiliary beam L1 is substantially the same as the direction in which the filler wire 78 extends, which will be described later, and the entire width 79 of the filler wire 78 is irradiated as the measurement irradiation unit 69.
[0039]
The vertical width T2 of the auxiliary beam L1 is set to be longer than the entire width 79 of the filler wire 78, and the auxiliary beam L1 in the portion that does not irradiate the measurement irradiation unit 69 applies the steel plates W1 and W2 to the welded member irradiation unit 70. Irradiated as The longitudinal direction of the auxiliary beam L1, that is, the direction of the width T2, is adjusted by the rotating means 54 so as to coincide with the Z-axis direction.
[0040]
The rotation means 54 (see FIG. 2) includes a third actuator 71, and a drive gear 74 is attached to the rotation shaft 72 of the third actuator 71. The rotating member 62 is provided with a ring-shaped driven gear 76 that meshes with the driving gear 74, and the rotating means 54 has a function of adjusting the relative positions of the auxiliary beam L1 and the laser beam L2. Further, the first and second prisms 56 and 58 and the camera 60 may rotate integrally with the rotating means 54.
[0041]
When the filler wire 78 is fed to the welded part P, the filler wire 78 has an action of being overheated and melted by the laser beam L2 together with the steel plates W1 and W2 to fill the gaps between the steel plates W1 and W2. By this action, the welding strength between the steel plate W1 and the steel plate W2 can be improved.
[0042]
As shown in FIG. 1, the filler wire 78 is fed by the filler wire feeding device 80 at a constant speed corresponding to the welding speed. The filler wire feeding device 80 can be moved by a fourth actuator (wire position adjusting unit) 82, whereby the filler wire 78 can be moved and adjusted in the X-axis direction and the Y-axis direction, and the angle in the height direction can also be adjusted. Movement adjustment of θ1 and horizontal angle θ2 (see FIG. 3) is possible. The adjustment operation of the fourth actuator 82 is controlled by a command signal supplied from the control mechanism 16.
[0043]
The control mechanism 16 includes an actuator control unit 90, a robot control unit 92, a position calculation unit 94, and a laser height calculation unit 96. The control mechanism 16 controls the drive of the laser oscillator 40.
[0044]
The actuator control unit 90, the robot control unit 92, the position calculation unit 94, and the laser height calculation unit 96 may be integrated with each other.
[0045]
The actuator control unit 90 controls driving of the first to fourth actuators 24, 64, 71 and 82, and the robot control unit 92 controls driving of a robot (not shown) including the robot arm 14.
[0046]
The position calculation unit 94 basically has a function of calculating the position of the filler wire 78 based on the position and shape of the measurement irradiation unit 69 from the image captured by the camera 60.
[0047]
The laser height calculation unit 96 basically has a height (light projecting unit height) relative to the welded part P of the casing 38 based on the distance ΔX (see FIG. 3) between the welded member irradiation part 70 and the welded part P. ) It has a function of calculating Y1 (see FIG. 1).
[0048]
Next, a method of welding the steel plate W1 and the steel plate W2 while adjusting the position of the filler wire 78 mainly using the function of the position calculation unit 94 will be described with reference to FIGS. Note that the processing shown in FIG. 4 is actually executed continuously every minute time, and so-called real-time processing is possible.
[0049]
First, in step S1 of FIG. 4, the laser beam L2 is irradiated to the butted portion of the steel plate W1 and the steel plate W2, and the auxiliary beam L1 is irradiated to the filler wire 78.
[0050]
Next, in step S <b> 2, the desired field of view is picked up by the camera 60 through the first prism 56 and the second prism 58 from the tip opening of the shield nozzle 44.
[0051]
The imaging data includes a welding site P (see FIG. 3), a measurement irradiation unit 69, and a welded member irradiation unit 70, and the imaging data is supplied to the control mechanism 16. In the control mechanism 16, for example, an image 100 (see FIG. 5) obtained by pre-processing the acquired data by binarization is generated and supplied to the position calculation unit 94. The image 100 is also supplied to the laser height calculation unit 96.
[0052]
Next, in step S3, the measurement irradiation unit 69 is extracted from the image 100, and the position and shape (imaging information) of the measurement irradiation unit 69 are obtained. That is, regarding the position, the center-of-gravity position G (XG, ZG) of the measurement irradiation unit 69 is obtained. The center-of-gravity position G indicates the center of gravity in the horizontal plane, and the X-axis coordinate value is XG and the Z-axis coordinate value is ZG. Regarding the shape, the deviation ε in the Z-axis direction and the width T3 in the X-axis direction of the two end points 69a and 69b of the measurement irradiation unit 69 are obtained.
[0053]
Next, in step S4, a deviation amount ΔZ in the Z-axis direction of the filler wire 78 is obtained from the center of gravity position G. That is, the Z-axis coordinate value ZG of the gravity center position G and the specified position Z related to the Z-axis ₀ And the deviation amount ΔZ is set to ΔZ = Z ₀ Calculated as -ZG. Specified position Z ₀ May use a preset value or obtain the position of the center of gravity of the welded part P and adopt the Z-axis component thereof.
[0054]
Next, in step S5, the amount of deviation ΔY in the Y-axis direction of the filler wire 78 is obtained from the center of gravity position G. That is, as shown in FIG. 6, the Z-axis coordinate value ZG of the gravity center position G and the specified position X related to the X-axis ₀ And the amount of deviation ΔX in the X-axis direction is ΔX = X ₀ Calculated as -XG. Then, by using this deviation amount ΔX, the deviation amount ΔY in the Y-axis direction is expressed as ΔY = ΔX · tan θ. _L1 Asking. θ _L1 Is an angle formed by the auxiliary beam L1 and the horizontal plane.
[0055]
Next, in step S6, the angle θ in the height direction of the filler wire 78 from the width T3 (see FIG. 5) in the X-axis direction of the measurement irradiation unit 69. 1 Ask for. As shown in FIG. 7, the angle θ1 is an angle θ formed by the width T3, the auxiliary beam L1, and the horizontal plane. _L1 , And the width T1 of the auxiliary beam L1. Further, the determined angle θ1 and the specified angle θ1 in the height direction ₀ The amount of deviation Δθ1 from Δθ1 = θ1 ₀ Obtained as -θ1.
[0056]
Next, in step S7, the horizontal angle θ2 is obtained from the width T3 in the X-axis direction of the measurement irradiation unit 69 and the deviation ε in the Z-axis direction. The angle θ2 is θ2 = Tan ^-1 It can be calculated as (ε / T3). Further, the obtained angle θ2 and the specified angle θ2 in the horizontal direction ₀ The amount of deviation Δθ2 from Δθ2 = θ2 ₀ Calculated as -θ2. The specified angle θ2 ₀ Is preferably set to 0 ° with respect to the X-axis direction because the formula can be simplified.
[0057]
Next, in step S <b> 8, the position calculation unit 94 supplies the calculated deviation amounts ΔX, ΔY, ΔZ, Δθ1 and Δθ2 to the actuator control unit 90.
[0058]
Finally, in step S9, when the obtained deviation amounts ΔX, ΔY, ΔZ, Δθ1, and Δθ2 are not “0” or not within the allowable range, the actuator deviation is expressed by “0”. Alternatively, the fourth actuator 82 is operated so as to be within the allowable range.
[0059]
In this way, the position calculation unit 94 calculates the deviation amounts ΔX, ΔY, ΔZ with respect to the X axis, the Y axis, and the Z axis of the filler wire 78 from the barycentric position G, the deviation ε, and the width T3 obtained from the image 100. Can be sought. Further, deviation amounts Δθ1 and Δθ2 relating to the angle in the height direction and the horizontal direction can be obtained. Furthermore, the angle of the filler wire 78 can be adjusted by these deviation amounts Δθ1 and Δθ2.
[0060]
Next, a method of welding the steel plate W1 and the steel plate W2 while adjusting the height of the laser irradiation mechanism 12 mainly using the function of the laser height calculation unit 96 will be described with reference to FIG. Note that the processing shown in FIG. 8 is actually executed continuously every minute time, and so-called real-time processing is possible. The laser height calculator 96 operates in parallel with the position calculator 94.
[0061]
Steps S101 and S102 in FIG. 8 are the same processes as steps S1 and S2, and are shared without being distinguished in practice.
[0062]
Next, in step S <b> 103, the laser height calculation unit 96 acquires the image 100 (see FIG. 5), and then extracts the welding site P and the welded member irradiation unit 70 from the image 100. Further, the position (XP, ZP) of the welded part P on the horizontal plane and the X-axis coordinate value XP of the welded member irradiation part 70 ₁ Ask for. When the welded part P has a predetermined area in the image 100, the position of the center of gravity is set as the position (XP, ZP) of the welded part P. Further, the image 100 is an image centered on the optical axis O by the function of the first prism 56, and since the welding site P is on the optical axis O, the center of the image 100 is positioned at the position of the welding site P (XP , ZP).
[0063]
Next, in step S104, the distance ΔXP between the member-to-be-welded irradiation portion 70 and the welding site P is set to ΔXP = XP−XP ₁ Asking.
[0064]
Next, in step S105, the height Y1 of the condenser lens 48 with respect to the welded part P is obtained using the distance ΔXP. As can be seen from FIG. 6, the height Y1 is Y1 = ΔXP · tan θ. _L1 It is calculated as + Yc. Here, Yc is the distance between the intersection point Q and the condenser lens 48 when the intersection point between the auxiliary beam L1 and the optical axis O is the intersection point Q, and is stored in the laser height calculation unit 96. is there.
[0065]
Next, in step S106, the focal length (specified height) Y of the condensing lens 48. ₀ And the amount of deviation ΔY1 between the height Y1 and ΔY1 = Y ₀ Calculate as -Y1. Focal length Y of condenser lens 48 ₀ Is stored in the laser height calculation unit 96 as a specified value.
[0066]
Next, in step S107, the laser height calculation unit 96 sets the focal length Y. ₀ Is supplied to the actuator control unit 90. The actuator control unit 90 refers to the acquired deviation amount ΔY1, and when ΔY1 is not “0” or not within the allowable height range, the deviation amount ΔY1 is “0” or within the allowable height range. The first actuator 24 is operated.
[0067]
In this way, the laser height calculation unit 96 can calculate the height Y1 of the condenser lens 48 with respect to the welded part P based on the distance ΔXP obtained from the image 100. Further, by supplying the deviation amount ΔY1 to the actuator controller 90, the focal length Y of the condenser lens 48 is increased. ₀ Can be appropriately controlled with respect to the welding site P. In particular, when a plurality of types of steel plates W1 and W2 which are members to be welded exist and have different thicknesses, the height Y1 is set to the focal length Y for each of the steel plates W1 and W2. ₀ Can be controlled to match. Further, the same control can be performed when the thicknesses of the steel plates W1, W2 are continuously changing.
[0068]
Next, a laser welding apparatus 10a according to a second embodiment and a welding method using the laser welding apparatus 10a will be described with reference to FIGS.
[0069]
As shown in FIG. 9, the laser welding apparatus 10a basically has a configuration in which the auxiliary beam L1 in the laser welding apparatus 10 according to the first embodiment is replaced with a pair of line beams L3 and L4 irradiated from the outside. It is. Hereinafter, the same components as those of the laser welding apparatus 10 described above are denoted by the same reference numerals, and detailed description thereof is omitted.
[0070]
The laser welding apparatus 10a is provided with a pair of line beam oscillators 101 and 102 at the lower end of the rotating member 62. The line beams L3 and L4 output from the line beam oscillators 101 and 102 are parallel to each other. The filler wire 78 and the steel plates W1 and W2 are irradiated. The line beams L3 and L4 are preferably a laser having a wavelength different from that of the laser beam L2, for example, an IR (infrared) laser, because it can be clearly identified in the image 100.
[0071]
Further, the line beams L3 and L4 need not be lasers, and may be, for example, directional light or radiation.
[0072]
In the laser welding apparatus 10a, the deflection lens 50, the advance / retreat means 52, the second actuator 64, and the rod 66 in the first embodiment are unnecessary.
[0073]
As shown in FIG. 10, the line beams L3 and L4 are irradiated as a line beam having a width T1a, and the irradiation direction of the line beams L3 and L4 is the direction in which the width T1a extends from the filler wire 78. The full width 79 of the filler wire 78 is irradiated as auxiliary irradiation lines 104 and 106.
[0074]
The vertical width T2a of the line beams L3 and L4 is set to be longer than the entire width 79 of the filler wire 78, and the line beams L3 and L4 in the portions not irradiated with the auxiliary irradiation beams 104 and 106 cover the steel plates W1 and W2. Irradiation is performed as welding member irradiation sections 108 and 110. The vertical direction of the line beams L3 and L4, that is, the direction of the width T2a is adjusted by the rotating unit 54 so as to coincide with the Z-axis direction.
[0075]
The control mechanism 16a includes an actuator control unit 90 and a robot control unit 92 similar to those in the first embodiment, and further includes a position calculation unit 94a and a laser height calculation unit 96a. Further, the control mechanism 16 a drives and controls the line beam oscillators 101 and 102 together with the laser oscillator 40.
[0076]
The position calculation unit 94a determines the position of the filler wire 78 based on the position and shape of the region (measurement irradiation unit) 112 (see FIG. 11) surrounded by the auxiliary irradiation lines 104 and 106 obtained from the image captured by the camera 60. It has a function to calculate. Specifically, the region 112 is handled in the same manner as the measurement irradiation unit 69 in the first embodiment, and the deviation amounts ΔX, ΔY, ΔZ, Δθ1, and Δθ2 are calculated and then supplied to the actuator control unit 90.
[0077]
Further, in this case, since the welding site P is irrelevant, only the wavelengths of the irradiation portions by the line beams L3 and L4, that is, the auxiliary irradiation rays 104 and 106 and the welded member irradiation portions 108 and 110, when imaged by the camera 60 are taken. You may image so that it may be exposed to. In this way, since the welding site P by the laser beam L2 does not appear on the image 100, the auxiliary irradiation lines 104 and 106 can be easily extracted.
[0078]
Furthermore, the width T1a of the line beams L3 and L4 can be set to an arbitrary width depending on the arrangement of the line beam oscillators 101 and 102, and can be set to a width that can be easily extracted from the image 100.
[0079]
The laser height calculation part 96a is the X coordinate value XPa of the to-be-welded member irradiation part 108. ₁ It has a function of calculating a height Y1 (see FIG. 6) of the casing 38 with respect to the welded part P based on a distance ΔXPa between the welded part P and the welded part P (see FIG. 11). Specifically, the distance ΔXPa is handled in the same manner as the distance ΔXP in the first embodiment, and the height Y1 of the condenser lens 48 with respect to the welded part P is obtained. In this case, the intersection point Q in the first embodiment may be an intersection point of the optical axis O and the line beam L3.
[0080]
After this, the focal length Y ₀ By supplying the deviation amount ΔY1 related to the above to the actuator controller 90 and operating the first actuator 24, the heights of the condenser lens 48 and the laser irradiation mechanism 12 can be adjusted.
[0081]
Thus, in the second embodiment, the same effect as in the first embodiment can be obtained.
[0082]
In the first and second embodiments, the measurement irradiation unit 69 and the region 112 are simply handled as a rectangle or a parallelogram, but strictly speaking, the measurement irradiation unit 69 and the region 112 are fillers. Since the shape has a circular arc along the outer periphery of the wire 78, the position calculation units 94 and 94a may perform processing in consideration of the circular arc shape.
[0083]
Further, for the measurement irradiation unit 69 and the region 112, the position of the filler wire 78 is calculated using the center of gravity position G indicating the position, the deviation ε indicating the shape, and the width T3. The area (imaging information) of the region 112 may be used. For example, since the width T3 and the area are in a proportional relationship, the area can be used as an alternative to the width T3.
[0084]
Furthermore, in the second embodiment, a line beam similar to the line beams L3 and L4 may be added and three or more line beams may be used. In this case, any two may be selected and processed according to the position of the filler wire 78.
[0085]
Of course, the laser welding apparatus and welding method according to the present invention are not limited to the above-described embodiment, and various configurations can be adopted without departing from the gist of the present invention.
[0086]
【The invention's effect】
As described above, according to the laser welding apparatus and the welding method of the present invention, it is possible to detect the horizontal position, height and / or angle of the filler wire fed when performing laser welding. Achieved. Based on these horizontal positions, heights and / or angles, the filler wire can be adjusted to a defined position and / or a defined angle.
[0087]
Further, since the height of the light projecting portion can be detected, the height of the light projecting portion of the laser can be adjusted according to the focal length.
[Brief description of the drawings]
FIG. 1 is an explanatory side view showing a state in which a part of a laser welding apparatus for carrying out a laser welding method according to a first embodiment of the present invention is broken.
FIG. 2 is a perspective explanatory view of advance / retreat means and rotation means constituting the laser welding apparatus.
FIG. 3 is a schematic perspective view showing a welding site and its periphery in the first embodiment.
FIG. 4 is a flowchart showing a procedure for performing laser welding while controlling the position of a filler wire.
FIG. 5 is an explanatory diagram showing an image captured by a camera in the first embodiment.
FIG. 6 is an explanatory side view showing a mutual positional relationship among a condenser lens, a laser beam, an auxiliary beam, and a filler wire in the first embodiment.
FIG. 7 is an explanatory side view showing a relative angle between an auxiliary beam and a filler wire in the first embodiment.
FIG. 8 is a flowchart showing a procedure for performing laser welding while controlling the height of a condenser lens and a laser irradiation mechanism.
FIG. 9 is an explanatory side view showing a state in which a part of a laser welding apparatus for carrying out a laser welding method according to a second embodiment of the present invention is broken.
FIG. 10 is a schematic perspective view showing a welding site and its periphery in a second embodiment.
FIG. 11 is an explanatory diagram showing an image captured by a camera in the second embodiment.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 10, 10a ... Laser welding apparatus 12 ... Laser irradiation mechanism
14 ... Robot arm 16, 16a ... Control mechanism
24, 64, 71, 82 ... Actuator
40 ... laser oscillator 46 ... collimator lens
48 ... Condensing lens 50 ... Deflection lens
56, 58 ... right angle prism 60 ... camera
69 ... Irradiation part for measurement 70 ... Irradiation part to be welded
72 ... Rotating shaft 78 ... Filler wire
79 ... Wide width 80 ... Wire feeding device
90 ... Actuator control unit 94, 94a ... Position calculation unit
96, 96a ... Laser height calculation unit 100 ... Image
112 ... area L1 ... auxiliary beam
L2 ... Laser beam L3, L4 ... Line beam
P ... Welding site W1, W2 ... Steel
X ₀ , Z ₀ ... Specified position XP ₁ ... X-axis coordinate value
Y ₀ ... focal length Y1 ... height
Yc: Distance between intersection and condenser lens ε: Deviation
θ1 ... Angle in the height direction θ2 ... Angle in the horizontal direction

Claims (6)

The laser is irradiated to the weld portion irradiated with weld members from a first direction, it feeds feeding the filler wire from a second direction different from the first direction to the weld irradiation portion, melting the filler wire by the laser In the laser welding apparatus for welding the member to be welded,
A measurement beam having a width wider than the full width of the filler wire, irradiated to a middle portion of the filler wire from a third direction different from the first direction and the second direction, and intersecting the filler wire When,
A camera that images a measurement irradiation unit that is an irradiation position of the measurement beam on the filler wire from at least a fourth direction different from the second direction and the third direction ;
A position calculation unit for calculating at least the height direction position of the filler wire on the basis of the position of the measuring portion irradiated with the image captured by the measuring beam irradiation angle and the camera,
When the position calculated by the calculating unit position is outside of the allowable range of positions a prescribed position location as a reference, and the wire position adjusting unit for moving and adjusting the filler wire to the allowable position range,
A laser welding apparatus comprising: The laser welding apparatus according to claim 1, wherein
The measurement beam is a parallel beam with a constant thickness,
The position calculation unit calculates the angle of the filler wire based on the thickness of the measurement beam and the shape of the measurement irradiation unit in the image,
The wire position adjustment unit, when the angle calculated by the position calculating unit is outside of the allowable angle range of the specified angle as a reference, and the features that you move adjusting the filler wire to the allowable angle range Laser welding equipment. In the laser welding apparatus according to claim 1 or 2 ,
The respective light projecting portions of the laser and the measurement beam are configured such that the relative positions are fixed,
The measurement beam irradiates at least a part of the remaining portion that irradiates the measurement irradiation portion of the filler wire to the welded member,
The camera captures, within one image, a welded member irradiation part of the welded member irradiated by the measurement beam and a welding irradiation part irradiated by the laser.
The laser height for calculating the height of the laser projecting portion with respect to the welding irradiation portion based on the distance between the welded portion irradiation portion and the welding irradiation portion and the irradiation angle of the measurement beam in the one image. A calculation unit;
When the height calculated by the laser height calculation unit is out of an allowable height range based on a specified height, the respective light projecting units of the laser and the measurement beam are directed to the welding irradiation unit. An advancing / retreating drive unit that integrally moves forward / backward to adjust the movement within the allowable height;
A laser welding apparatus comprising: In the laser welding apparatus according to claim 1 or 2 ,
The measuring beam is a laser welding apparatus and generates by deflecting a portion of the laser. In the laser welding apparatus of any one of Claims 1-4,
The measuring beam is a laser welding device according to claim Rukoto such from two parallel beams in a line. The laser is irradiated to the weld portion irradiated with weld members from a first direction, it feeds feeding the filler wire from a second direction different from the first direction to the weld irradiation portion, melting the filler wire by the laser In the laser welding method of welding the member to be welded,
A measurement beam having a width wider than the full width of the filler wire is applied to a middle portion of the filler wire from a third direction different from the first direction and the second direction, and intersects the filler wire. Steps,
A step of imaging at least the second direction and the third direction different from the fourth the measurement beam irradiated portion der Ru camera measuring portion irradiated with in the filler wire from the direction of,
Calculating at least the height direction position of the filler wire on the basis of the position of the measuring portion irradiated with the image captured by the measuring beam irradiation angle and the camera,
When calculated position of the filler wire is outside of the defined position location allowable position range relative to the laser welding method characterized by a step of moving and adjusting the filler wire to the allowable position range .

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