A bonded body includes a first metal piece, a second metal piece, and a spacer. The first metal piece has a first surface and a protrusion protruding on the first surface. The second metal piece has a second surface, and the second surface of the second metal piece is bonded to the first surface of the first metal piece at the protrusion. The spacer has an electrically insulating property. The spacer is provided on the first surface of the first metal piece, and located between the first metal piece and the second metal piece. The first metal piece and the second metal piece are arranged to face each other such that a portion of the first surface of the first metal piece outside of the spacer is exposed from the second metal piece.

In a main metal piece 60 and an inner cylinder 70 serving as cylindrical bodies before welding, a second end surface 75 is an inclined surface that inclines toward an end portion opposite from the second end surface 75 as the second end surface 75 extends toward the center axis, and an angle 2a is 5 to 15. Thus, the distance between a first end surface 65 and the second end surface 75 positioned in resistance welding increases toward the center axis, and an angle c (=angle 2a) between the first end surface 65 and the second end surface 75 is 5 to 15.

In a main metal piece 60 and an inner cylinder 70 serving as cylindrical bodies before welding, a second end surface 75 is an inclined surface that inclines toward an end portion opposite from the second end surface 75 as the second end surface 75 extends toward the center axis, and an angle 2a is 5 to 15. Thus, the distance between a first end surface 65 and the second end surface 75 positioned in resistance welding increases toward the center axis, and an angle c (=angle 2a) between the first end surface 65 and the second end surface 75 is 5 to 15.

An all-in-one jigless projection loading system for a vehicle is adapted to load and assemble a body component to a vehicle body. The all-in-one jigless projection loading system may include: a fixing bracket fixed to an arm of a robot; a position adjusting member rotatably mounted to the fixing bracket; a gripper mounted to the fixing bracket to be movable backward and forward, and gripping the body component; an array unit mounted to the position adjusting member, and arraying the body component; and a welding unit mounted to the fixing bracket, and projection-welding the body component to a vehicle body.

An all-in-one jigless projection loading system for a vehicle is adapted to load and assemble a body component to a vehicle body. The all-in-one jigless projection loading system may include: a fixing bracket fixed to an arm of a robot; a position adjusting member rotatably mounted to the fixing bracket; a gripper mounted to the fixing bracket to be movable backward and forward, and gripping the body component; an array unit mounted to the position adjusting member, and arraying the body component; and a welding unit mounted to the fixing bracket, and projection-welding the body component to a vehicle body.

A steel plate frame and a thin plate are made of different materials. A plurality of through holes are formed in a portion of the thin plate to be placed on the steel plate frame. A plurality of projections 6c are formed on a support plate, each of the projections being allowed to be inserted into a corresponding one of the through holes. An adhesive is applied to a portion of the steel plate frame on which the thin plate is placed. The thin plate is placed on the steel plate frame, and the steel plate frame and the thin plate are bonded together by the adhesive. The support plate is placed on the thin plate to insert the projections into the through holes. The projections and the steel plate frame are welded to form a plurality of welded spots.

A component loading-welding system for welding a component panel to a vehicle body panel includes a rotation portion body having first and second opposing sides. The first opposing side is coupled to a robot arm. A picking device is installed in the rotation portion body and is configured to hold and release the component panel. A vehicle body pressurizing tip is installed in the rotation portion body. A pressurizing portion body is rotatably installed at the second opposing side of the rotation portion body. A pin clamp is installed in the pressurizing portion body and is configured to clamp the component panel. A component pressurizing tip is installed in the pressurizing portion body and is configured to apply pressure to the component panel. A multi point projection welding method is also disclosed.

A component loading-welding system for welding a component panel to a vehicle body panel includes a rotation portion body having first and second opposing sides. The first opposing side is coupled to a robot arm. A picking device is installed in the rotation portion body and is configured to hold and release the component panel. A vehicle body pressurizing tip is installed in the rotation portion body. A pressurizing portion body is rotatably installed at the second opposing side of the rotation portion body. A pin clamp is installed in the pressurizing portion body and is configured to clamp the component panel. A component pressurizing tip is installed in the pressurizing portion body and is configured to apply pressure to the component panel. A multi point projection welding method is also disclosed.

A securing system, such as a welding system, includes a robot configured to transfer a part to a home position. A securing station has a frame and a gun supported on the frame. The gun includes first and second members movable relative to one another, which are first and second weld gun electrodes, for example. The gun is configured to secure a component to the part in a securing position during a securing operation. A float assembly interconnects the gun to the frame and is configured to permit the gun to glide relative to the welding frame between the home position and the securing position. A homing assembly includes a homing guide configured to release the welding gun from the home position during the securing operation, such as resistance welding fasteners to sheet metal workpieces.

A securing system, such as a welding system, includes a robot configured to transfer a part to a home position. A securing station has a frame and a gun supported on the frame. The gun includes first and second members movable relative to one another, which are first and second weld gun electrodes, for example. The gun is configured to secure a component to the part in a securing position during a securing operation. A float assembly interconnects the gun to the frame and is configured to permit the gun to glide relative to the welding frame between the home position and the securing position. A homing assembly includes a homing guide configured to release the welding gun from the home position during the securing operation, such as resistance welding fasteners to sheet metal workpieces.