| 摘要 |
PROBLEM TO BE SOLVED: To carry out adequate lubrication of the sliding portions of the driving mechanism without using bellows by providing material to seal the clearance between the plunger and the cylinder and the swash plate side from a passage opened to the body and the cylinder. SOLUTION: Sliding friction of a load supporting part is reduced by the relative rotational speed and lubrication with oil. For oil lubrication, a mechanism for retaining oil in a swash plate chamber 44 formed between the body and a cylinder block 16 is required. To fill this requirement, a shaft seal 38 is provided at a slipper 13 side of an intake slot 30 of a plunger 14, creating a seal between the fuel and oil during reciprocating motion of the plunger 14. This seals the clearance between the plunger 14 and a cylinder bore 17, and the shaft seal 38 becomes the boundary between the fuel and the oil. In this mechanism, the low pressure intake pressure at the intake slot 30 is always acting on the shaft seal 38: the pressure does not become large like the internal pressure in a pump chamber 42, and a constant pressure acts on the shaft seal 38. This improves both the sealing properties and the reliability of the shaft seal 38. |
