US 12,435,725 B2
Pump monitoring device and vacuum pump
Kota Watanabe, Kyoto (JP)
Assigned to SHIMADZU CORPORATION, Kyoto (JP)
Filed by SHIMADZU CORPORATION, Kyoto (JP)
Filed on Jun. 29, 2019, as Appl. No. 16/458,041.
Claims priority of application No. 2018-168194 (JP), filed on Sep. 7, 2018.
Prior Publication US 2020/0080564 A1, Mar. 12, 2020
Int. Cl. F04D 25/06 (2006.01); F04D 27/00 (2006.01); G01M 13/00 (2019.01)
CPC F04D 25/06 (2013.01) [F04D 27/001 (2013.01); G01M 13/00 (2013.01); F05D 2260/80 (2013.01); F05D 2270/335 (2013.01)] 9 Claims
OG exemplary drawing
 
1. A vacuum pump for performing exhaust for a process chamber in which various processes are performed for a processing target, comprising:
a pump main body including a rotor, a stator, and a motor configured to rotatably drive the rotor; and
a pump controller including a pump monitoring device and configured to drivably control the motor, wherein
the pump monitoring device comprises a control circuit including:
an acquisition section configured to, after a rotation number of a rotor of the vacuum pump has reached a rated rotation number, acquire a physical amount representing an operation state of the vacuum pump over a first period of time to set a waveform of the acquired physical amount as a reference waveform, and over a second period of time later than the first period of time to set an actual measurement waveform of the physical amount;
a comparison section configured to compare the actual measurement waveform of the physical amount with the reference waveform of the physical amount by calculating a difference between a value of the actual measurement waveform and a value of the reference waveform at multiple different corresponding time points only in a difference computing region that is only a part of the actual measurement waveform and the reference waveform to determine a degree of coincidence between the actual measurement waveform and the reference waveform;
a determination section configured to determine an abnormality due to an increase of reactive product in the vacuum pump based on the degree of coincidence determined by the comparison section; and
a notification section to automatically output an indicia of abnormality based on a determination of the determination section.