US Patent 7484448 Motor-vehicle pyrotechnic unit

A pyrotechnic release unit has a generally tubular casing having an open rear end and an open front end and adapted to be secured to one of a pair of separable vehicle parts, a pin releasably retained in the front end of the housing and adapted to be secured to the other of the pair of separable vehicle parts, a support plug fittable through the rear end into the housing and carrying a pyrotechnic charge turned toward the front end, and a latch element bearing rearward on the casing and forward on the support plug and sufficiently strong that on explosion of the charge the support plug remains fixed in the casing and the pin is blown out of the front end of the casing.