Compact capacitive acceleration sensor

An acceleration sensor (10, 10', 10'') in which a metal blade member (24) having a source plate portion (24a), attachment portion (24p) and integral resilient beams (24b) extending between the source plate portion and the attachment portion is attached to a pin (22) received in turn in a bore (18a) of a substrate (18). The metal blade member (24) is mounted on the substrate (18) so that the source plate portion is a selected distance from a detect plate (18b) mounted on the substrate. The sensor is disposed in a cylindrical housing (12, 12', 12'') which can be directly mounted to a circuit board (50) through terminal pins (18g, 18h, 18i) or can be provided with a threaded fastener (12''d). In one embodiment first and second sensor modules are received in a housing (42) to sense acceleration forces in two perpendicular directions. In another embodiment tab (30b) extending from a signal conditioning circuit (30) is placed between a connector body (20') and the sidewall (12b) of housing (12) with a detent (12c) formed in the sidewall (12b) to effect an electrical connection between circuit (30) and housing (12''). An O-ring gasket (13) is placed between the sidewall (12b) and the connector body (20') outboard of the detent to provide an environmental seal.