A flexible cable is constructed in a band-like shape by sandwiching a plurality of conductive wires with a pair of insulating films, and a lead block is constructed by fixing a plurality of joint bars to a resin body. In a connecting structure of the flexible cable and the lead block, a part of one of the insulating films is removed so that the conductive wires are exposed at an end of the flexible cable. In addition, through holes for preventing deformation are formed in the remaining insulating film at positions between the exposed parts of the conductive wires. The exposed parts of the conductive wires are connected to the joint bars at positions close to the through holes by ultrasonic welding.