Teijin Seiki Co., Ltd.

Tsuyoshi Nachi

Masanori Hirai

Hiroyuki Takenaka

Kiyoshi Ando

Hidekazu Yokoi

In a screw type vacuum pump which includes a housing provided with a rotor chamber, a pair of screw rotors in mesh with each other rotably provided in the rotor chamber, a transfer chamber of gas formed between an inner wall of the housing and flutes of the aforesaid pair of screw rotors, and a suction port and an exhaust port communicated to the transfer chamber, the gas being sucked from the suction port into the transfer chamber and exhausted from the exhaust port, by providing the aforesaid exhaust port in a side face of the housing, it is possible to form a larger exhaust port, and a time until the port is blocked with deposits can be prolonged.

Vacuum exhausting apparatus

In screw rotors ( ) which are each provided with a screw tooth ( ) having a spiral addendum surface portion (  ) and a deddendum surface portion (  ), and are used as a pair of male and female, between the addendum surface portion (  ) and deddendum surface portion (  ) of the screw tooth ( ), there is provided the pitch circumference portion (  ) which forms a predetermined angle range of circular arc having a definite radius rp on an optional transverse cross section, and the radius of the pitch circumference portion (  ) is set such that, when the opposing rotors are meshed with each other, out of the meshing clearances between the male and female screw teeth ( ), the clearance g between the pitch circumference portions (  ) becomes smaller than the clearances g g g between the other portions.

Screw rotors and screw machine

A rotary motion to longitudinal motion converting mechanism comprising a passive rack with a plurality of teeth, a plurality of active racks respectively having a plurality of teeth having the same pitch as that of the teeth of the passive rack and meshing with the passive rack, and a plurailty of rotatable crankshafts respectively having eccentric circular portions different in phase from one another and respectively having the active racks supported on the eccentric circular portions in such a manner that the passive rack is moved in its longitudinal direction through the active racks by rotary motions of the plurality of rotatable crankshafts.

Growing community of inventors

Mie, Japan

Tsuyoshi Nachi