| 摘要 |
A door closer (20) is attachable to a door (24) and includes a cylinder (36) which forms a chamber (44) in which a piston element (50) is movable to move fluid from the chamber to a reservoir (82) upon opening of the door. After the door (24) has been opened to a position, for example, of ninety-five to one hundred degrees, continued opening of the door causes the fluid to be compressed within the chamber (44) and to be directed only through a back check valve (95) to the reservoir (82). This results in the development of an adjustable "back check" condition to provide a counterforce to the continued opening of the door, A passageway (150) is formed in cylinder (36) to allow fluid to flow relatively freely from chamber (44) to reservoir (82) until an inward end (56) of piston element (50) has travelled a prescribed distance "x". This prescribed distance of travel represents the opening of door (24) to ninety-five to one hundred degrees from the door's normally closed position. <IMAGE> |
