Method and device for controlling the pumping speed of vacuum pumps

摘要

The pump (1) consists of several steps (2a,2b,2c), and has a high vacuum connection (4) and a prevacuum connection (5). A gas stream is generated between the two connections. Part of the gas stream is branched off at a point (7) between the two connections, and the high vacuum connection is supplied again. The portion of the gas stream which is used again to supply the high vacuum connection is controlled by a regulating valve (9). A vacuum system is used in order to set a pump consisting of several steps, where the system consists of several pumps.