| 摘要 |
PROBLEM TO BE SOLVED: To provide a piston type vacuum pump which runs in stable condition without the eccentric friction wear of a roller pin, so that the roller can run smoothly for longer life, suppressing the friction wear between the roller and the cam. SOLUTION: A push rod 7 reciprocates by the rotation of cam and a roller 30 which is pressed to the cam driven by an engine or the like. A piston is provided to the push rod 7. The roller 30 is adapted to be rotatable with a roller pin 26. The roller pin 26 is retained rotatably in the push rod 7. |
