Aspirating apparatus

843,345. Suction bellows. RUBEN, H., and HESSE, H. Jan. 24, 1957 [March 2, 1956], No. 2628/57. Class 8(1). A hand or foot operated bellows 1 suitable for evacuating a flask 25 to which it is connected by a flexible tube 24 and having automatic suction and discharge valves 9, 8 is biassed to its fully extended position by a spring 4 which is preloaded e.g. by a chain 19 connecting upper and lower end plates 2, 3 of the bellows 1. As shown the suction and discharge valves comprise spring-biassed balls 21, 7 located in end wall 2, but in a modification the discharge valve comprises a loose disc seated above an aperture in the upper end wall whereas the suction valve comprises a loose ball located in a housing at the vacuum flask end of the tubing 24. In a further modification, the bellows and flask are mounted on a base plate on opposite sides of a carrying handle, and in a still further modification, the bellows is of the hinged type, the biassing spring being pre-loaded by an external stop.