SUPPORT MEMBER, DETECTION UNIT, SIDE SURFACE COLLISION DETECTION SYSTEM, AND OCCUPANT RESTRAINT SYSTEM

An acceleration sensor (40R) for detecting a side surface collision which occurs in a vehicle is mounted on a beam (112) of a door via a support member (50). When a force due to a collision acts on the beam (112), this force is dampened by the support member (50) and thereafter transmitted to the acceleration sensor (40R). As a result, even if the beam (112) moves at an acceleration exceeding the rated input of the acceleration sensor (40R), the acceleration of the acceleration sensor (40R) is suppressed to a level not greater than the rated input. Accordingly, the side surface collision can be detected with high accuracy without using a sensor having a high rated input.