| 摘要 |
A method for making a hydraulic door closer includes the steps of molding material to form an elongated single-piece housing having a longitudinal cylindrical bore extending from a first open end thereof to a closed second end, a transverse intersecting bore, and mounting feet; installing a spring within the cylindrical bore at the closed end of the housing; installing a piston within the cylindrical bore in contact with the spring, the piston having a toothed rack thereon and an opening in each end to permit passage of fluid therethrough; installing a pinion gear in the transverse intersecting bore in meshed engagement with the toothed rack; installing an endplug with a port in the first end of the longitudinal cylindrical bore; and inserting a valve device through the port, for controlling flow of fluid through the piston, and for thereby controlling closing speed of the door. The single-piece housing as well as other components may be molded from metal or polymeric materials. Polymeric materials are preferred for their flexibility, lubricity, and moldability. |
