GB719646A - Dash-pot controlled devices - Google Patents

Abstract

719,646. Dashpots. BRATT COLBRAN. Ltd. Feb. 17, 1953 [Feb. 18, 1952], No. 4199/52. Class 108(3) A dashpot comprises a body part a having three bores b. c and s containing respectively, a spring-loaded piston d, a movable member (e.g. a valve e), and a spring-loaded tappet rod q operable by the piston d, a lever t passing through a hole in the movable member having one end in operative connection with the rod q and being adjustably supported at the other end by the body part. In the construction shown, the movable member is a valve e which controls flow of gas between an inlet passage g (not visible in Figs. 1 and 4), and an outlet passage f. A threaded plug in the passage g serves to adjust the rate of gas flow. The lever t bears on a slot in the tapped rod q, on a projection x in a transverse bore of the valve e and is fulcrummed in an eccentric recess in a plug u. The plug u may be rotated to adjust the fulcrum position. In operation, on downward manual displacement of the piston d, an arm p releases the rod q which is driven downwards by the action of a spring r. This actuates the lever t, and thereby depresses the valve e to open the port f. The return stroke of the piston d under the action of a spring i, occurs at a controlled rate due to flow through a restriction k, until the piston is by-passed by a groove m. The piston then rises quickly, and at this stage the arm p re-engages the rod q, which acts via the lever t to close e the valve e. The valve e may alternatively be a switch-actuating or other member. Specification 633,519 is referred to.