Vacuum pump with a centrifugal dust collector and a metal mesh dust collector mounted in parallel

Abstract

The objects of the present invention are to remove the dust in a closed container, to keep the pressure in the closed container within a predetermined range, and to shorten the maintenance time of a vacuum pump system. The present invention provides a centrifugal dust collector 2 on main pipes which connects a furnace body 1, a mechanical press 9 and a dry pump 10, and a metal mesh dust collector 15 on a bifurcated pipe in a single-crystal semiconductor pulling apparatus. When the vacuum pump process begins, the metal mesh dust collector 15 collects amorphous silicon generated in the furnace 1. As the pressure in the furnace is reduced, the centrifugal dust collector 2 collects the dust particles instead. Since the gas flow rate increases as the vacuum state become higher, the critical diameter of collectable particles decreases, thereby improving the dust collection efficiency. The collected amorphous silicon accumulates on the bottom of the centrifugal dust collector and can be easily removed so as to facilitate maintenance. Moreover, there will be very little pressure variance in the furnace since no dust filter is blocked.

Dependencies are inferred from the claim text.