US Patent 7438335 Compact electric strike with preload release capability

In a door strike for captivating and releasing a door bolt, the combination comprising a longitudinally elongated carrier, a longitudinally elongated solenoid supported by the carrier, the solenoid having a longitudinally movable plunger, a trip lever pivotally supported in or on the carrier, a laterally extending actuating arm pivotally supported in or on the carrier to be pivoted as the plunger moves longitudinally in response to solenoid energization, thereby to pivot the trip lever, a generally longitudinally extending blocking arm or arms pivotally supported in or on the carrier to be released for pivoting when the trip lever is pivoted, and a door bolt retainer or retainers pivotally supported in the carrier to be released for pivoting when the blocking arm or arms are released for pivoting, thereby to release the door bolt from captivation, for movement with the door.