| 摘要 |
The present invention provides a piston assembly which comprises: a first piston wherein a first oil flow path is formed; a second piston coupled to the first piston for an oil stay space to be interconnected to the first oil flow path, wherein a second oil flow path is formed, and the oil stay space interconnected to the second oil flow path is formed; an inlet ball opening and closing an exit of the first oil flow path; and an elastic member arranged in the oil stay space to support the inlet ball, thereby removing a plastic cage wherein deformation possibility is high in a high temperature environment, and reducing the whole volume of a pump. |
