| 摘要 |
606,227. Door closing and check devices. NEWMAN & SONS, Ltd., W., and ROLLASON, S. A. Jan. 11, 1946, No. 979. [Class 65 (i)] [Also in Group XXXII] In a fluid check device for a door, of the type comprising a piston movable within a cylinder so that oil or other fluid is forced, during the closing of the door, through a groove of tapering form or varying width, the latter is formed in the wall of either the piston or the cylinder, and an edge of the cylinder or piston moves over the groove and is so shaped that on relative rotation of the piston and cylinder the extent to which it covers the groove can be varied. The piston 11 is pivoted at 17 to the operating ring 10 of a floor-spring movement, which may be of the type described in Specification 606,228. During opening of the door, the piston is forced outwards by a spring 13, and oil or other fluid from the interior of the casing 1 enters the cylinder 12 past a non-return valve 14. During closing of the door, the piston is forced into the cylinder and the oil is released through a groove 18 which is tapered to provide a progressively increasing retardation. A member 15 is grooved to engage a fulcrum in the form of a rib 16 and carries a worm 22 which engages teeth 21 cut in the periphery of an extension 20 of the cylinder 12. One end of the worm 22 has a slot which can be engaged by a screwdriver for the purpose of rotating the cylinder to vary the position of an inclined edge 19 relative to the groove 18, thereby altering the degree of retardation. The groove 18 may be formed on the inner face of the cylinder wall, the inclined edge 19 then being formed on the piston. The variation of degree of retardation may be accomplished by rotating the piston instead of the cylinder. The positions of piston and cylinder may be transposed. The device may be double acting. The invention may be applied to arrangements in which the spring and check are housed in a shoe fitted to a corner of the door. The inclined edge 19 may be cut obliquely curved instead of being cut obliquely in a straight line. |
