| 摘要 |
PROBLEM TO BE SOLVED: To improve the reliability of an electrical connection between a terminal pin and a lead wire by providing caulking parts formed at several sports by punching the terminal pin so as to fixedly connect the lead wire inserted into the terminal pin of a base. SOLUTION: A lead wire 7 is externally inserted into a terminal pin 4 provided in a lamp base, punching caulking parts 44 and 46. Then, a projecting part 45 of a leading end side caulking part 44 breaks an oxide film on the surface of the lead wire 7, and cuts thereinto, and establishes a conductive relationship with the inside of the lead wire 7 in a wide area. On the other hand, a bulb side caulking part 46 is made electrically conductive when a projecting part 47 slightly cuts into the surface of the lead wire 7, and the lead wire 7 is pinched and pressed between the bulb side caulking part 46 and an inner wall portion in a pinch to restrain its movement. In this manner, the caulking parts 44 and 46 have different rates of deformation of the lead wire 7, and one of the caulking parts 44 and 46 establishes good electrical contact, and the other of the caulking parts 44 and 46 controls a shearing force due to external stress to prevent disconnection, stably securing the lead wire 7 to a terminal pinch. |
