Abstract: In a welding station, one end of a positioning jig is held by a positioning robot, and the other end of the positioning jig is held by a positioning jig holder mechanism. The positioning robot is moved for positioning and fixing a vehicle body frame, which is fixed to the positioning jig, in any attitude, and a desired welding operation is performed on the vehicle body frame.

Abstract: In a welding station, one end of a positioning jig is held by a positioning robot, and the other end of the positioning jig is held by a positioning jig holder mechanism. The positioning robot is moved for positioning and fixing a vehicle body frame, which is fixed to the positioning jig, in any attitude, and a desired welding operation is performed on the vehicle body frame.

Abstract: In assembling a vehicle body frame for a motorcycle by welding front and rear frame subassemblies to each other, the following steps are carried out: a step of positioning left and right rear portions of the front frame subassembly by a pair of front positioning device movable at least in a widthwise direction of the vehicle body frame, a step of clamping a head pipe by a front clamp device which is capable of being moved in vertical and longitudinal directions of the vehicle body frame and is capable of being tilted longitudinally, a step of positioning left and right rear portions of the rear frame subassembly by a pair of rear positioning device movable in the longitudinal, widthwise and vertical directions of the vehicle body frame, a step of clamping left and right front portions of the rear frame subassembly by a pair of rear clamp means movable in the longitudinal, widthwise and vertical directions of the vehicle body frame, and a step of welding the front and rear frame subassemblies to each other.

Abstract: On a setting cart which is movable back and forth between a setting station and a vehicle body assembly station, there are provided floor panel setting members, side sill receiving members and side panel forcing members which force side panels toward a floor panel from a lateral outward. In the setting station, the floor panel and the side panels which are set in position on the setting cart are transferred to a jig which is disposed in a side portion of the vehicle body assembly station. The side panels are welded to the floor panel by welding robots which are disposed at a level below the jig. In the above-described arrangement, the side sill receiving members and the side panel forcing members are set on the setting cart so as to be retractable into shunted positions free from interference with the welding robots in welding operation. The welding work by the welding robots can thus be started without waiting for the returning of the setting cart to the setting station.

Abstract: In assembling a vehicle body frame for a motorcycle by welding front and rear frame subassemblies to each other, the following steps are carried out: a step of positioning left and right rear portions of the front frame subassembly by a pair of front positioning device movable at least in a widthwise direction of the vehicle body frame, a step of clamping a head pipe by a front clamp device which is capable of being moved in vertical and longitudinal directions of the vehicle body frame and is capable of being tilted longitudinally, a step of positioning left and right rear portions of the rear frame subassembly by a pair of rear positioning device movable in the longitudinal, widthwise and vertical directions of the vehicle body frame, a step of clamping left and right front portions of the rear frame subassembly by a pair of rear clamp means movable in the longitudinal, widthwise and vertical directions of the vehicle body frame, and a step of welding the front and rear frame subassemblies to each other.

Abstract: In an industrial robot having a rotatable robot main body 3, a first robot arm 5 which is mounted, via a first joint portion 4, on an upper end of the robot main body 3 so as to be vertically swingable, and a second robot arm 7 which is mounted, via a second joint portion 6, on a front end of the first robot arm 5 via a second joint portion 6 so as to be vertically swingable, the assembling is facilitated and the miniaturization of the robot is attained. The first and second joint portions 4, 6 are arranged in a cantilevered construction in which each of the first and second robot arms 5, 7 is supported on the robot main body 3 and the first robot arm 5, respectively, in a cantilevered manner via a driving reduction gear Ry, Rw of each of the first and second robot arms 5, 7, respectively. The driving reduction gears Ry, Rw are disposed so as to cross an identical central plane "a" that includes an axis of rotation of the robot main body 3.

Abstract: The instrument panel is clamped at both longitudinal ends thereof onto an assembly jig mounted on a robot arm. The jig holding the panel is inserted widthwise into the car cabin through a door opening. The jig is moved to a preassembly position where the end walls of the panel overlap outer side surfaces of mounting brackets previously installed in the car cabin. The end walls of the panel are then fastened in place by nut runners provided at both ends of the assembly jig. The nut runners are mounted on tool holders which are able to perform a floating movement in a plane perpendicular to the car width direction. Positioning devices are provided at both ends of the jig to correct the position of the tool holders with respect to the brackets to align and position the panel so that the mounting holes in the end walls of the panel line up with the tapped holes in the brackets.

Abstract: The instrument panel is clamped at both longitudinal ends thereof onto an assembly jig mounted on a robot arm. The jig holding the panel is inserted widthwise into the car cabin through a door opening. The jig is moved to a preassembly position where the end walls of the panel overlap outer side surfaces of mounting brackets previously installed in the car cabin. The end walls of the panel are then fastened in place by nut runners provided at both ends of the assembly jig. The nut runners are mounted on tool holders which are able to perform a floating movement in a plane perpendicular to the car width direction. Positioning devices are provided at both ends of the jig to correct the position of the tool holders with respect to the brackets to align and position the panel so that the mounting holes in the end walls of the panel line up with the tapped holes in the brackets.