| 摘要 |
PURPOSE:To obtain a downsized mechanical firing sensor in which erroneous function is prevented positively by blocking unnecessary movement of an inertial mass positively thereby sustaining operable state positively. CONSTITUTION:A lock lever 72 is disposed retractively in the track of an inertial mass 40. Engaging part 84 of the lock lever 72 corresponds to the engaging groove 41 in the inertial mass 40 and when they engage each other, rotation of the lock lever 72 is blocked thus blocking movement of the inertial mass 40. In other words, urging force of a return spring 86 does not substantially function to block movement of the inertial mass 40. Consequently, even a so- called tension type safety device can employ a small-sized return spring 86 having low urging force thus realizing total downsizing. |
