Piston Pump

Piston pumps are durable, fairly simple devices. The basic piston pump is made up of a piston, a chamber, and a pair of valves.

The pump operates by driving down into the chamber, thereby compressing the media inside—in a hand pump this is usually air. Once the pressure of the air exceeds that of the outlet valve spring, the compressed media is sent through the open outlet valve.

When the piston is drawn back up, it opens the inlet valve and closes the outlet valve, thereby utilizing suction to draw in additional media for compression.

Piston pumps are a type of reciprocating pump, which are positive-displacement pumps that can use a piston, plunger or diaphragm to displace fluids. The input and output valves in a piston pump are check valves; this term is used to describe devices that limit flow in a system to one direction.

Piston pumps can be driven manually or automatically, and there are a number of devices that can be used to drive the piston. A common piston pump design is the rotary piston pump, which uses a rotating shaft or wheel to drive the piston.

The rotating component is attached to an intermediary shaft at a point away from its center, and this shaft is attached to the piston. As the rotating component turns, it drives the shaft and piston down and then pulls it back up.