| 摘要 |
A door closer 10, for controlling angular movement of a door, comprises a housing 11; a piston 16, having a longitudinal axis, slidable in a passage in the housing; a cam member 19 which is connected to, supported on or integral with a rotatable axle 28 which extends transversely through the housing; and a spring member 20 positioned in the passage in the housing for biasing an end of the piston into engagement with a surface of the cam member. The apparatus also includes a holding member 40 which extends through a wall of the housing and engages a part of the piston, the holding member inhibiting rotation of the piston about its longitudinal axis. The holding member 40 which aids in guiding reciprocal movement of the piston may be a cylindrical member which engages a flattened surface of the piston. The cam member may be heart-shaped. The door closer may comprise an adjustment means 24 for adjusting the biasing force of the spring 20 which also is ideally hydraulically damped by mechanism 50. |
