Patent ID: 7690292

Claim:
A linear drive for a vehicle occupant restraint system, especially for a belt buckle tensioner, comprising a cylinder ( 18 ), a piston ( 20 ) that is selectively moved in the cylinder ( 18 ) and that has a locking part ( 22 ) that is firmly connected to a traction element ( 12 ) and comprising at least one locking member ( 30 ) that is arranged movably between the locking part ( 22 ) and an inner wall of the cylinder ( 18 ), said locking part ( 22 ) having at least one obliquely disposed first clamping surface ( 26 ) that is arranged in such a way that, when the traction element ( 12 ) makes a pushing movement, said clamping surface ( 26 ) clamps the locking member ( 30 ) between the locking part ( 22 ) and the cylinder ( 18 ), wherein the locking part ( 22 ) has at least one obliquely disposed second clamping surface ( 28 ) with at least one associated locking member ( 30 ) that is slanted in the opposite direction relative to the first clamping surface ( 26 ).