Patent attributes
A high-pressure fuel pump (10) used in a fuel system includes an electric motor (14) having a drive shaft (16) to which is attached a pumping element (18). A fuel inlet passage allows low-pressure fuel to be drawn into the pump, and a fuel outlet passage (24) allows high-pressure fuel to be pumped to an internal combustion engine (E). A check valve assembly (30) is installed in the outlet passage and includes a check valve (36) which, when the pump is off, blocks an inlet (38) into the outlet passage to prevent fuel flow through the passage and into the pump resulting in a decrease in pressure in the fuel system. When the pump is operating, the check valve is forced away from the inlet to open the valve and allow fuel to freely flow through the passage. The fuel flows both around and through the check valve as it flows through the outlet passage. A retainer (32) seats against a shoulder adjacent an outlet end (44) of the outlet passage, and a spring (34) has one end which seats against the retainer and the other end of which seats against a base of the check valve. Flow of fuel around and through the check valve, when the valve is open, enables quiet operation of the check valve so when the pump is operating, there is no discernible noise or chattering from the check valve.
