Vacuum pump

Abstract

A vacuum pump comprises: a rolling bearing configured to support a rotor shaft provided at a pump rotor; a lubrication fluid storage section configured to store lubrication fluid to be supplied to the rolling bearing; a MEMS element including, at a rotor-shaft-side lubrication fluid circulation path in a lubrication fluid circulation path between the rolling bearing and the lubrication fluid storage section, an infinitesimal flow rate pump configured to discharge a liquid droplet of the lubrication fluid; and a first flow path of a capillary structure configured to move the lubrication fluid of the lubrication fluid storage section to the infinitesimal flow rate pump by capillary force.

What is claimed is: 
     
         1 . A vacuum pump comprising:
 a rolling bearing configured to support a rotor shaft provided at a pump rotor;   a lubrication fluid storage section configured to store lubrication fluid to be supplied to the rolling bearing;   a MEMS element including, at a rotor-shaft-side lubrication fluid circulation path in a lubrication fluid circulation path between the rolling bearing and the lubrication fluid storage section, an infinitesimal flow rate pump configured to discharge a liquid droplet of the lubrication fluid; and   a first flow path of a capillary structure configured to move the lubrication fluid of the lubrication fluid storage section to the infinitesimal flow rate pump by capillary force.   
     
     
         2 . The vacuum pump according to  claim 1 , further comprising:
 a lubrication path member provided adjacent to the rolling bearing at the rotor shaft and having a conical surface forming part of the lubrication fluid circulation path,   wherein a radius of the conical surface from a center of the rotor shaft is set greater toward the rolling bearing, and the lubrication fluid discharged from the infinitesimal flow rate pump and adhering to the conical surface is moved in a direction of the rolling bearing on the conical surface by centrifugal force.   
     
     
         3 . The vacuum pump according to  claim 1 , wherein
 the infinitesimal flow rate pump is configured to discharge the lubrication fluid to the rolling bearing.   
     
     
         4 . The vacuum pump according to  claim 1 , further comprising:
 at least one of a vibration sensor configured to detect vibration of the rolling bearing or a temperature sensor configured to perform non-contact detection of a temperature of the lubrication fluid circulation path; and   a control section configured to drivably control the infinitesimal flow rate pump based on a detection result of at least one of the vibration sensor or the temperature sensor, thereby controlling an amount of the lubrication fluid to be transferred by the infinitesimal flow rate pump.   
     
     
         5 . The vacuum pump according to  claim 4 , further comprising:
 a warning section configured to output deterioration information on the rolling bearing based on the detection result of at least one of the vibration sensor or the temperature sensor.   
     
     
         6 . The vacuum pump according to  claim 1 , further comprising:
 a lubrication path member provided adjacent to the rolling bearing at the rotor shaft,   wherein the lubrication path member has
 a conical surface forming part of the lubrication fluid circulation path, and 
 an axial end surface connected to the conical surface and forming another part of the lubrication fluid circulation path, and 
   the MEMS element provided with the infinitesimal flow rate pump is arranged facing the axial end surface, and the liquid droplet of the lubrication fluid is discharged from the infinitesimal flow rate pump to the axial end surface.   
     
     
         7 . The vacuum pump according to  claim 6 , wherein
 the MEMS element has
 a temperature sensor configured to capture infrared light emitted from a surface of the rotor shaft or a surface of the lubrication path member as a temperature measurement target surface to measure a temperature, and 
 an infrared light incident window that the infrared light guided by the temperature sensor enters, and 
   a first protection section configured to prevent adherence of the lubrication fluid to the infrared light incident window is further provided.   
     
     
         8 . The vacuum pump according to  claim 7 , further comprising:
 a second protection section configured to prevent adherence to the temperature measurement target surface.   
     
     
         9 . The vacuum pump according to  claim 1 , further comprising:
 a flow rate sensor configured to detect an amount of the lubrication fluid to be transferred by the infinitesimal flow rate pump; and   a diagnosis section configured to make a diagnosis on an amount of the lubrication fluid stored in the lubrication fluid storage section based on a detection result of the flow rate sensor.