Hand-operated reciprocating pump

Abstract: A reciprocating pump includes a cylinder; a piston including apertures and an annular bottom flange; a first check valve secured to a piston rod and including an annular groove; a coupling at cylinder bottom; a sealing ring sandwiched between the cylinder bottom and the coupling; a second check valve engaged with the ring and including tunnels and a bottom socket; and a metal block fitted in the socket. Pushing a handle upward will move the piston rod downward to sealingly engage the flange with the groove, remove air from the cylinder, and block the coupling by both the socket and the block. Pushing the handle downward will move the piston rod upward to disengage the flange with the groove, open the second check valve, suck fluid into the cylinder through the coupling, the tunnels, and the apertures, and discharge the fluid. (end of abstract)