Abstract: An apparatus of welding a plurality of parts comprises a plural pairs of jigs, a plurality of heating plates, a working region, a heating-plate stocker, a heating-plate standby region, and a heating-plate slider. The pairs of jigs supports a plurality of parts, and each pair of the jigs has a shape different from another pair of jigs. The heating plates respectively correspond to each pair of the jigs. The working region is for welding the parts with the jigs and the heating plates. The heating-plate stocker stocks and heats the heating plates. The heating-plate standby region is for standing by for moving the heating plates with heating between the working region and the heating-plate stocker. A heating-plate slider is for sliding the heating plates between the heating-plate standby region and the heating-plate stocker.

Abstract: To prevent the temperature from rising locally in a closed space so as to make the temperature in an annealing furnace uniform, an apparatus and method for annealing welded parts includes an annealing furnace 2 which is substantially closed; a doorway 5 through which welded parts 4 are placed into and out of the annealing furnace; a carriage mechanism 6 for carrying welded parts on a predetermined course in the annealing furnace; infrared lamps 9 for heating welded parts carried in the annealing furnace; and a circulating mechanism 12 for circulating hot air in the annealing furnace. Thus, the annealing (distortion-eliminating) efficiency of the welded parts is improved.

Abstract: A vibration welding apparatus for welding synthetic resin parts together by vibrating one of the resin parts while the resin parts are in contact with each other. An upper jig for supporting one of the synthetic resin parts, a lower jig for supporting the other of the snythetic resin parts and a vibrating member to which the upper jig is attached are provided in the apparatus. The jigs are held together by bolts which can withstand the vibrating motions. Head portions of the bolts are inserted into insertion holes of the upper jig, notches of spacers are engaged with the shaft portions of the bolts between an attached portion of the upper jig and the head portions of the bolts, and the bolts are fastened to the vibrating member in the state where the notches are engaged with the shaft portions, so that the attached portion is fastened through the spacers by the head portions of the bolts and the vibrating member to thereby attach the upper jig to the vibrating member.