Vibration rejecting impact sensor, particularly to trigger a vehicular collision safety system

Abstract

A moveable mass is part of a resilient spring system, in which the spring is a leaf spring restrained in a housing. Strain gauges are applied to the leaf spring, the outputs of which are integrated in a bi-polar integrator. Vibration of the leaf spring will cause sequential integration in reverse direction and, accordingly, a low output signal; deflection of the mass, for example upon on impact, will cause the integrator to provide a strong integrating signal which can trigger a collision safety system. The inherent, or characteristic frequency of the system is so selected that it is above the frequency occurring upon an impact of the sensor, or upon collision, but below the frequency occurring due to concussions to which the vehicle, or the mounting post of the apparatus on the vehicle, is subjected in use, or repair.