Electric diaphragm pump with offset slider crank

A diaphragm pump system comprising:

• a crankcase;
• a crankshaft at least partially positioned within the crankcase and operatively coupled to an electric motor, the crankshaft being rotatable about a rotational axis;
• at least three pistons radially arranged around the crankcase, each piston of the at least three pistons coupled to a throw of the crankshaft by a connecting rod and being reciprocally displaceable within a piston cylinder and along an axis of motion between a suction stroke and a discharge stroke, the axis of motion for each piston of the at least three pistons intersects a connection between the piston and the connecting rod;
• and
• at least three diaphragm housings, each diaphragm housing of the at least three diaphragm housings being coupled to an end of a piston cylinder and configured to at least partially define a pumping chamber and pump fluid through the pumping chamber as the piston reciprocates,
• wherein the axis of motion of each of the at least three pistons does not intersect the rotational axis of the crankshaft such that a peak magnitude of piston side load forces encountered during the discharge stroke is reduced and a peak magnitude of piston side load forces encountered during the suction stroke is increased such that, relative to an arrangement in which the axes of motion do intersect the rotational axis, a closer balance is attained between the peak magnitudes of the piston side load forces of the discharge stroke and the suction stroke.

A diaphragm pump comprising:

• a crankcase;
• a crankshaft at least partially positioned within the crankcase, the crankshaft being rotatable about a rotational axis;
• a piston coupled to the crankshaft by a connecting rod, the piston being reciprocally displaceable within a piston cylinder between a suction stroke and a discharge stroke;
• a diaphragm housing coupled to the piston cylinder, the diaphragm housing configured to at least partially define a pumping chamber;
• and
• a diaphragm coupled to an end of the piston, the diaphragm configured to pump fluid through the pumping chamber as the piston reciprocates,
• wherein the piston cylinder extends about a central longitudinal cylinder axis that intersects the rotational axis, and wherein the piston is pivotally coupled to the connecting rod by a wrist pin that is positioned along a central axis of the wrist pin that is parallel to, and linearly offset from, the central longitudinal cylinder axis such that, relative to an arrangement in which the wrist pin is not linearly offset from the central longitudinal cylinder axis, a peak magnitude of piston side load forces encountered during the discharge stroke is reduced and a peak magnitude of piston side load forces encountered during the suction stroke is increased so as to attain a closer balance between the piston side load forces of the discharge stroke and the suction stroke.