Oblon, Spivak, McClelland, Maier & Neustadt
Vacuum pump
 Disclosed is a vacuum pump having a peripheral groove vacuum pump unit which includes a casing provided with an inlet port and an outlet port; a rotor disposed within the casing and including a rotor shaft journaled on the casing, a rotor body fixed to the rotor shaft and provided integrally with a rotor disk; and a stator fixedly disposed within the casing and provided with an annular groove receiving the peripheral portion of the rotor disk. Both sides of the peripheral portion of the rotor disk are cut in steps or portions of the side walls of the annular groove corresponding to the peripheral portion of the rotor disk are cut in annular recesses to form flow passages on both sides of the peripheral portion of the rotor disk. Partitions are projected from the stator into the flow passages. The starting ends of the flow passages on the inlet side of the partitions communicate with the inlet port, and the terminating ends of the same on the outlet side of the partitions communicate with the outlet port. The vacuum pump is capable of operating at a high pumping speed. Spaces between the peripheral portion of the rotor disk and the inner surfaces of the annular groove of the stator need not be sealed and large clearances may be formed therebetween, so that the components of the vacuum pump can easily be machined without requiring high machining accuracies. 
Osaka Vacuum, Ltd.
F
F04D
inventional
Tatsuji Tetsuro Keiichi Masashi
Ikegami Ohbayashi Yoshida Iguchi