The working principle of the injection pump assembly, the injection pump manufacturer to introduce it:

The work of the fuel injection pump assembly is to transfer the engine rotation to the camshaft through the coupling (or driving gear) and timing device, and then the tappet converts this rotary motion into reciprocating motion to make the pump components (plunger assembly) of each cylinder work.

The plunger is driven upward by the camshaft and moves downward under the action of the plunger spring, i.e. carrying out reciprocating movement (up and down).

The pump housing of the injection pump assembly contains an oil storage chamber, which is often filled with low pressure fuel filtered by the fuel filter. The inlet and outlet holes of the plunger sleeve are connected to the oil storage chamber.

When the camshaft enters the downward stroke of the tappet, the plunger moves downward under the action of the plunger spring. When the top end of the plunger falls to the oil inlet and outlet holes on the plunger sleeve, fuel begins to rush into the inside of the plunger sleeve.