| 摘要 |
963,463. Hydraulic shock-absorbers. VEREINIGTE BAUBESCHLAG - FABRIEKEN GRETSCH & CO. G.m.b.H. Nov. 5, 1962 [Nov. 11, 1961], No. 41698/62. Heading F2S. [Also in Division E2] A door closer comprises a damping piston 13 movable in a damping cylinder 2 and loaded by the closer spring 12 and a second piston 17 movable in a reservoir cylinder 15 and rigidly connected to the damping piston by a rod 18 extending through the cylinder head 16, movement of the pistons causing transfer of the damping medium between the two cylinders. The closer is adapted to be mounted in a door 1 pivoted at 4, and the piston-rod 7 is connected to a flexible traction member 8 pivoted to the door frame 5 and 6. The traction member is preferably formed as a steel cable surrounded by a synthetic plastics sheath 9, but may alternatively comprise a stout cable of synthetic plastics material with or without a relatively thin steel core. In a modification the traction cable is pivoted to a rigid link which is pivoted to the frame at 6 to prevent buckling of the cable when the door is opened wide. When the door is being opened oil flows freely from the cylinder 15 to the chamber 14 through a non-return valve in a channel 19. When the door closes the oil can pass through a channel 23 (Fig. 3), with a regulating valve 20 and also through the central channel containing the connecting rod 18. The cross-sections of the rod and the central channel are made to vary in the longitudinal direction so that the damping commences when the door is about 70 degrees from its closed position, increases as the door continues to close, and ceases when the door is about to latch. The connecting rod may be adjusted in the longitudinal direction. A safety valve 21 is provided; alternatively a spring- loaded flanged synthetic plastics sleeve may be provided around the rod 18 at the point where it emerges into the cylinder 15. This sleeve normally closes the oil channel along the rod, but can lift if the pressure becomes excessive. |
