Improvements in or relating to door closers.

摘要

The door closer is of the kind which acts, for example between a door hinge stile and a hinge jamb and has a body (11) for mounting usually in the stile, from which body (11) a spring-biased tension member (12) extends correspondingly for anchoring to an anchoring point (for example in said jamb), wherein a hydraulic cylinder-piston damper (20) is interposed between said tension member (12) and a biasing spring (15) therefor, said damper (20) being adapted to allow fluid in use to flow restrictedly past said piston (31) when said tension member (12) is moved in door-closing and door-opening directions; characterised in that the cylinder (17) of the hydraulic cylinder piston damper (20) is formed of a plastics material, and the cylinder (17) is resiliently expansible in response to an increase in pressure therein such that the clearance between the piston (31) and cylinder (17) is increased to permit increased flow of fluid around the piston (31). <IMAGE>