Roller bush for fuel injection pump

摘要

A roller bush for a fuel injection pump is interposed between a metal roller and a pin. The roller is forced to contact with a cam reciprocating a plunger, and the pin supports the roller rotatably about a rotational axis at either axial side of the bush. Either axial end portions of the bush entirely consist of ceramic, each portions having the axial length from the corresponding axial end surface of L. The ratio of the axial length L to the entire axial length L0 of the bush is set to be equal to or larger than {(11-d)/16}, where d represents the inner diameter of the bush.