| 摘要 |
A fuel pump assembly comprises a pumping plunger for pressurising fuel within a pumping chamber during a plunger pumping stroke; and a cam follower arrangement for imparting drive to the pumping plunger including a cam follower member which cooperates with the pumping plunger. The cam follower arrangement is biased into engagement with a cam drive whilst a degree of relative movement along the plunger axis is permitted between the cam follower member and the pumping plunger. At least one of the pumping plunger and the cam follower member includes a surface provided with a feature which defines together with a facing surface of the other of the pumping plunger and the cam follower member, a cushioning volume therebetween for receiving fluid to provide a cushioning effect as the pumping plunger and the cam follower member move into contact with one another, in use. The feature includes a flat central portion and an annular region which is conical in form and which is angled relative to the facing surface. |
