| 摘要 |
PURPOSE:To prevent the timing for disengaging from an ignition pin a first and second trigger means for the inertial mass of an acceleration sensor from being advanced or retarded because of the wear of mating surfaces by allowing the second trigger means to be oscillated by the action of an acceleration less than a predetermined value, while locking the first trigger means so that it does not oscillate. CONSTITUTION:When an acceleration sensor 10 is exerted with an acceleration less than a predetermined value, an inertial mass 40 makes slight inertial movement from its original position; a trigger lever 42 oscillates in the direction of arrow A and in the opposite direction, while a trigger arm 48 does not oscillate; that is, the mating surfaces of the claw portion 46 of the trigger lever 42 and the end portion 48A of the trigger arm 48 oscillate, while the mating surfaces of the claw portion 52 of the trigger arm 48 and the flange portion 37 of an ignition pin 30 do not shake. Because of an energizing for exerted by a firing spring 38, a pressure working on the mating surfaces of the claw portion 46 of the trigger lever 42 and the end portion 48A of the trigger arm 48 is small compared with that working on the mating surfaces of the claw portion 52 of the trigger arm 48 and the flange portion 37 of the ignition pin 30. |
