A pump, for supplying high pressure fuel from a fuel tank to an engine via
a common rail, includes a motor assembly (20) mounted on top of the fuel
tank, a pump assembly (26) positioned within the fuel tank, and a support
column (32) rotatably connecting the motor assembly to the pump assembly.
A high pressure pump sub-assembly (46) includes a pump body (48) having a
drive bore (50) and multiple plunger bores (60) formed therein. The
external profile of a drive member (58) which is rotatable within the
drive bore engages the radially inner end of pumping plungers (62)
disposed in each of the plunger bores for a portion of each revolution to
reciprocally move the plungers between radially inner and outer limit
positions. Reciprocation towards the inner limit position induces a low
pressure in the radially outer end of the plunger bore, thereby drawing
fuel via the drive bore without the aid of a low pressure pump.
