office chair with a backrest must also run

摘要

The backrest of the office chair swivels about a horizontal axis and has an associated resetting spring in the form of a mechanical coil compression spring (14) which is mounted between a pressure bearing (10) associated with the backrest support (6), and a pressure bearing (13) associated with the seat support (5). A plunger piston (21) fixed on the pressure bearing is mounted coaxial in the coil compression spring and runs in a plunger sleeve (20) fixed on the other pressure bearing. The piston has radially outwardly aligned locking stops (26, 27) which in the extended position sit on the circumferential edge of the sleeve (20). The locking stops are formed by the end pieces of an expanding scissors.