Oblon, Spivak, McClelland, Maier & Neustadt
Vacuum pump
 A vacuum pump includes a casing provided with an inlet port and an outlet port; a turbo molecular pump unit disposed in an uppermost section, with respect to a flow direction of the gas, of the casing; a peripheral groove vacuum pump unit disposed in a middle section of the casing; and a vortex vacuum pump unit disposed in a lowermost section, with respect to the flow direction of the gas, of the casing. 
Osaka Vacuum, Ltd.
F
F04D
inventional
Keiichi Masashi Tatsuji Tetsuro
Yoshida Iguchi Ikegami Ohbayashi