Plunger diaphragm pump

The utility model relates to a plunger diaphragm pump which comprises a liquid inlet and outlet cover, a compression bin, a base, a piston diaphragm, a connecting rod, an eccentric wheel, a bearing and at least two umbrella-shaped one-way valves. The eccentric wheel is mounted on the connecting rod through the bearing, and the eccentric wheel is inserted into an output shaft of the driving motor in a penetrating manner; and one end of the connecting rod is connected with the piston diaphragm. The driving motor drives the eccentric wheel to control the connecting rod to pull the piston diaphragm to move back and forth, so that on one hand, the discharge flow of the plunger diaphragm pump can be precisely controlled; on the other hand, the diaphragm is directly connected with the connecting rod, the reciprocating motion deformation rate of the diaphragm is increased, and the conveying efficiency is relatively high; on the other hand, vacuum is not formed on the two sides of the diaphragm, and the normal service