Closure for openings in pumps

摘要

Closure for openings in the housings or covers of piston pumps or the like to withstand an operating pressure which is in part an alternating load comprising an inner cover, a loadable and releasable pressure-applying member therefor, a loading device for the pressure-applying member, and for the purpose of satisfactorily meeting the requirements of practical operation without critically loading screw-threads, the loading device comprises a compression spring arranged between the pressure-applying member and a backing member, and a biassing device is provided for producing a releasing force acting in the direction opposite to that of the force of the compression spring to initially release the spring force on the pressure-applying member so that the backing member can be finally adjusted into a position to produce the desired compressive force in use.