Fuel pump.

摘要

A fuel pumping apparatus of the rotary distributor type includes a fluid pressure actuable spill valve member (43) operable to terminate delivery of fuel through an outlet (18) from a bore (14) containing the pumping plungers (15). The valve member is moved to the open position by an actuating piston (44). One end of the cylinder (40) containing the actuating piston is connected to a low pressure source (35) of fuel by way of a non-return valve (37) and the same end of the cylinder can be connected by a control valve (26) to a high pressure source of fuel when spillage of fuel is required. Associated with the piston (44) is a balance piston (46) and the two pistons define a flow path for fuel from the one end of the cylinder (40) to the bore (14) to ensure that the bore is completely full of fuel prior to the next delivery of fuel through an outlet. <IMAGE>