US 12,392,352 B2
Vacuum exhaust apparatus and vacuum pump used therein
Yoshinobu Ohtachi, Yachiyo (JP); Yasushi Maejima, Yachiyo (JP); and Tsutomu Takaada, Yachiyo (JP)
Assigned to Edwards Japan Limited, Yachiyo (JP)
Appl. No. 17/779,116
Filed by Edwards Japan Limited, Yachiyo (JP)
PCT Filed Nov. 27, 2020, PCT No. PCT/JP2020/044377
§ 371(c)(1), (2) Date May 23, 2022,
PCT Pub. No. WO2021/112021, PCT Pub. Date Jun. 10, 2021.
Claims priority of application No. 2019-220773 (JP), filed on Dec. 5, 2019; and application No. 2019-221310 (JP), filed on Dec. 6, 2019.
Prior Publication US 2022/0397122 A1, Dec. 15, 2022
Int. Cl. F04D 27/00 (2006.01); F04B 49/06 (2006.01); F04B 49/22 (2006.01); F04D 19/04 (2006.01)
CPC F04D 27/007 (2013.01) [F04B 49/06 (2013.01); F04B 49/225 (2013.01); F04D 19/04 (2013.01)] 10 Claims
OG exemplary drawing
 
1. A vacuum exhaust apparatus comprising:
a vacuum pump including a rotor configured to rotate to exhaust an exhaust chamber, and a casing having an inlet port;
a valve located between the inlet port of the vacuum pump and an outlet port of the exhaust chamber; and
a controller configured to perform control such that a pressure in the exhaust chamber matches a target value,
wherein the controller is configured to control the pressure by:
adjusting, responsive to a first determination that an absolute value of a difference between the target value and the pressure is greater than a predetermined value, an opening degree of the valve based on a function of the difference between the target value and the pressure, and
adjusting, responsive to a second determination that the absolute value of the difference between the target value and the pressure is less than the predetermined value, a rotational speed of the rotor based on a function of the difference between the target value and the pressure.