| 摘要 |
A door closer has a housing (36, 38) defining a fluid containing chamber (44) and a fluid reservoir (82), and includes a piston (50) supported in the chamber for movement in one and an opposite direction in response to respective opening and closing movements of a door. A first fluid passageway (84) defined by the housing provides communication between the chamber (44) and the reservoir (82) for the free passage of fluid from the chamber (44) to the reservoir (82) in response to initial movement of the piston (50) in the one direction. A second fluid passageway (90, 138, 140, 142, 94), communicating with the chamber (44) at a position spaced in the one direction from the first fluid passageway (84), contains a check valve including a ball (144) biased by a spring (146) to a closed position for resisting the flow of fluid from the chamber (44) through the second passageway to the reservoir (82). The valve includes a valve element (95) which is threadably adjustable relative to a valve chamber in the housing to regulate the resistance to fluid flow. A third fluid passageway (90, 143, 142, 94), communicating with the chamber (44) at a position spaced from the first passageway and disposed in bypassing relation to the second fluid passageway, includes an adjustable metering orifice (91) and provides a free flow path from the chamber (44) to the reservoir (82). The size of the metering orifice (91) is also adjusted by threadably adjusting the valve element (95) relative to the valve chamber. <IMAGE> |
