Welding device and method for controlling welding device

A welding apparatus comprising:

• an articulated robot having a plurality of drive shafts;
• an end effector supported by the articulated robot;
• a tip shaft drive mechanism which is provided between a tip drive shaft of the articulated robot and the end effector and allows a tip shaft of the end effector to perform a weaving operation;
• and
• a drive control unit which drives the articulated robot and the tip shaft drive mechanism, wherein:
• the drive control unit comprises:
• a main-direction drive unit which allows the end effector to move along a welding line by driving the articulated robot;
• and
• a weaving drive unit which allows the tip shaft to perform a weaving movement, and
• in a case where a desired weaving locus of the tip shaft falls within a movable range of the tip shaft of the tip shaft drive mechanism, the weaving drive unit allows the tip shaft to perform a weaving operation that follows the weaving locus by driving the tip shaft drive mechanism, and
• in a case where the desired weaving locus does not fully fall within the movable range, the weaving drive unit allows the tip shaft to perform a weaving operation that follows the weaving locus by determining a supplemental movement distance of an excessive portion of a weaving movement component of the weaving locus beyond a movement limit of the movable range, driving the tip shaft drive mechanism up to the movement limit, and driving at least one of the drive shafts included in the articulated robot depending on the supplemental movement distance.

A method for controlling a welding apparatus, which uses a welding apparatus,

• the welding apparatus comprising:
• an articulated robot having a plurality of drive shafts;
• an end effector supported by the articulated robot;
• a tip shaft drive mechanism which is provided between a tip drive shaft of the articulated robot and the end effector and allows a tip shaft of the end effector to perform a weaving operation;
• and
• a drive control unit which drives the articulated robot and the tip shaft drive mechanism,
• wherein the method comprises driving the tip shaft drive mechanism to move the tip shaft of the end effector in a first-axis direction that is perpendicular to the tip shaft and in a second-axis direction that is perpendicular to the tip shaft and the first-axis direction.

A method for controlling a welding apparatus, which uses a welding apparatus,

• the welding apparatus comprising:
• an articulated robot having a plurality of drive shafts;
• an end effector supported by the articulated robot;
• a tip shaft drive mechanism which is provided between a tip drive shaft of the articulated robot and the end effector and allows a tip shaft of the end effector to perform a weaving operation;
• and
• a drive control unit which drives the articulated robot and the tip shaft drive mechanism;
• wherein
• when a weaving operation of the tip shaft of the end effector is performed along a welding line to follow a desired weaving locus,
• in a case where the desired weaving locus falls within a movable range of the tip shaft of the tip shaft drive mechanism, the method comprises driving the tip shaft drive mechanism, thereby performing the weaving operation that follows the weaving locus, and
• in a case where the desired weaving locus does not fully fall within the movable range, the method comprises determining a supplemental movement distance of an excessive portion of a weaving movement component of the weaving locus beyond a movement limit of the movable range, driving the tip shaft drive mechanism up to the movement limit, and driving at least one of the drive shafts included in the articulated robot depending on the supplemental movement distance, thereby performing the weaving operation that follows the weaving locus.