Backrest, for motor vehicle seats, has head restraint locking to eat structure via sliding locking bolt with sensor-controlled drive to move restraint during rear impact

摘要

The back rest has a locking device to fix a head restraint holder (3) to the seat structure (1). A moveable blocking part (4a) of the device is moved into a release position during a crash. The part has a sensor-controlled drive, which is activated during a crash. The drive may be a pyrotechnical unit, an electric magnet, or a pre-tension spring. The blocking part may be a sliding locking bolt or a pivoted ratchet.