| 摘要 |
A fuel pump arrangement for a fuel injection system is described. The fuel pump arrangement comprises one or more cam-driven pump units (110a, 110b), and the or each pump unit (110a, 110b) comprises a pumping chamber (112a, 112b) and a pumping element (114a, 114b) for pressurising fuel in the pumping chamber (112a, 112b). The or each pumping element (114a, 114b) is driven by a respective cam (116a, 116b) of the fuel pump arrangement to undergo at least one pumping stroke per revolution of the cam (116a, 116b). The fuel pump arrangement is configured such that the fuel volume displaced in a first pumping stroke is greater than the fuel volume displaced in a second pumping stroke. In this way, the efficiency of operation of the fuel pump arrangement can be improved. |
