US 12,378,967 B2
Vacuum pump
Shigeyoshi Nakatsuji, Chiba (JP); and Yoshiyuki Sakaguchi, Chiba (JP)
Assigned to Edwards Japan Limited, Chiba (JP)
Appl. No. 18/252,286
Filed by Edwards Japan Limited, Chiba (JP)
PCT Filed Dec. 3, 2021, PCT No. PCT/JP2021/044569
§ 371(c)(1), (2) Date May 9, 2023,
PCT Pub. No. WO2022/124240, PCT Pub. Date Jun. 16, 2022.
Claims priority of application No. 2020205721 (JP), filed on Dec. 11, 2020.
Prior Publication US 2024/0011496 A1, Jan. 11, 2024
Int. Cl. F04D 19/04 (2006.01); F04D 17/16 (2006.01); F04D 29/02 (2006.01); F04D 29/54 (2006.01)
CPC F04D 19/042 (2013.01) [F04D 17/168 (2013.01); F04D 19/044 (2013.01); F04D 29/023 (2013.01); F04D 29/547 (2013.01); F05D 2300/50212 (2013.01)] 5 Claims
OG exemplary drawing
 
1. A vacuum pump comprising:
a casing in which an inlet port is provided;
a rotating body which is enclosed in the casing and is rotatably supported;
a stator which is substantially cylindrical and is disposed on an outer periphery of the rotating body; and
a thread groove which is formed in at least one of an outer peripheral surface of the rotating body and an inner peripheral surface of the stator,
the vacuum pump exhausting gas sucked from a side of the inlet port to outside of the casing by rotating the rotating body, wherein
the stator extending downward from an upper end portion of the stator and having a lower extremity that is a free end, and
a cylindrical member, which is formed of a material having a linear expansion coefficient lower than a linear expansion coefficient of a material of the stator and reduces radial deformation at a time of thermal expansion of the stator, being disposed on an outer periphery of the stator and at the lower extremity of the stator.