Fuel injection pump.

摘要

There is disclosed an improved cam (20) for a fuel injection pump. The cam has a mountain-like cam projection (22) at its surface disposed in contact with a roller (10). The cam projection has a lift region (23) extending from a leading end (22a) thereof to a peak (22b) thereof. At the lift region, the cam is lifted in response to the rotation of the cam, so that a plunger (6) is moved to pressurize fuel in a pump chamber (4x). The lift region has first, second and third angle portions (23a to 23c) arranged in this order from the leading end of the cam projection toward the peak of the cam projection. The first angle portion (23a) serves to increase a lift speed of the cam, and terminates in a position (P) where the lift speed becomes the maximum. The second angle portion (23b) serves to lower the lift speed. The deceleration is greater at an initial section of the second angle portion than at a final portion of the second angle portion. The lift speed decreases with a greater deceleration at the third angle portion (23c) than at the final section of the second angle portion, and becomes zero at the peak of the cam projection. <IMAGE> <IMAGE>