HYDRAULIC PUMP, HYDRAULIC PUMP UNIT, AND HYDRAULIC DRIVING UNIT

摘要

A hydraulic pump can prevent breakage at a high pressure without providing a separate relief valve. A housing has a body side and a lid side that are divided by a surface perpendicular to a rotational axis of a hydraulic pump shaft. The lid-side housing is brought into oil-tight contact with the body- side housing by a spring. Contact between the body-side housing and the lid-side housing is maintained at a predetermined pressure corresponding to a maximum allowable pump hydraulic pressure.