FI750584

1504671 Reciprocating pumps A ELLILA 4 Feb 1976 [27 Feb 1975] 04387/76 Heading F1A [Also in Division F2] A device for adjusting the stroke of a camactuated diaphragm or piston pump comprises an abutment member 4 having maximum and minimum radii somewhat less than those of the cam 2 and rotatably mounted on the cam-shaft 1 adjacent the cam 2 so as to be engageable by the spring- loaded actuating rod 3 of the diaphragm or piston, the angular setting of member 4 limiting the return stroke of rod 3 by its loading spring. Member 4 may be an Archimedes spiral, as shown, or may comprise two arcuate portions joined together without a step. The angular setting of member 4 is determined by a stop pin 5 fixed thereto engaging an adjustable stop pin 7 for one direction of rotation of shaft 2 or another stop pin 8 for the opposite direction of rotation. Alternatively, member 4 may be adjusted by an electric motor or by a magnet. A plurality of cams and members 4 may be mounted on a common shaft for controlling a plurality of pumps.