| 摘要 |
PURPOSE: A multi-stage screw for a vacuum pump is provided to improve the degree of a vacuum by forming a smooth flow of fluid between first and second lead units by using a rotary plate which is detachable from a shaft, and to reduce an inner temperature and save power by minimizing a friction area with a housing unit. CONSTITUTION: A multi-stage screw for a vacuum pump comprises a pair of screws, a rotary plate(30), and a mounting member. The pair of screws includes a predetermined space unit(25) in the center of first and second lead units(21,22) in one end. The pair of screws is integrally formed in the outer circumference of a shaft(10). The rotary plate is mounted in the space unit of the screws and maintains the degree of a vacuum between the first and second lead units. The mounting member mounts the rotary shaft in the space unit of the screws. |
