Sensor and rollling bearing apparatus with sensor

Abstract

A rolling bearing apparatus with sensor includes a sensor unit retaining a plurality of types of sensors for detecting the status of a rolling bearing, in a single holder. The plurality of types of sensors are at least two types of sensors of a rotation speed sensor, a temperature sensor, and an acceleration sensor.

1 . An abnormality determining apparatus for a bearing unit including a rotating bearing: 
 a detecting unit, for detecting at least one of rotation speed, bearing temperature, and bearing vibration, in a sensor unit, wherein    the sensor unit is fixed to a seal case.    
   
   
       2 . The abnormality determining apparatus according to  claim 1 , wherein 
 an outer end section of the seal case projects outward from the seal ring, and    the sensor unit is coupled to the seal case for supporting the seal ring by a bolt being screw-engaged with a nut.    
   
   
       3 . The abnormality determining apparatus according to  claim 1 , wherein 
 the detecting unit comprises a sensor that detects a rotation speed, and    an encoder is fixedly fitted on an outer end section of an axle.    
   
   
       4 . The abnormality determining apparatus according to  claim 1 , wherein the sensor unit comprises: 
 a circuit member for processing a signal detected by the detecting unit, and    a circuit board mounting the detecting unit and the circuit member.    
   
   
       5 . The abnormality determining apparatus according to  claim 4 , wherein 
 the sensor unit includes a reference voltage generating circuit for supplying a reference voltage to the sensor of the detecting unit.    
   
   
       6 . The abnormality determining apparatus according to  claim 4 , wherein 
 a surface of the circuit board mounting the detecting unit and the circuit member is molded by a water-resistant resin.    
   
   
       7 . The abnormality determining apparatus according to  claim 6 , wherein the water-resistant resin is a silicone resin.  
   
   
       8 . The abnormality determining apparatus according to  claim 1 , wherein 
 the sensor unit comprises a sensor with the detecting unit for detecting at least one of rotation speed, bearing temperature, and bearing vibration, in a single holder, and    the holder is made of nonmagnetic material with good heat conductivity.    
   
   
       9 . The abnormality determining apparatus according to  claim 8 , wherein 
 the holder is made of at least one of aluminum, magnesium, copper, zinc, alloys thereof, or stainless steel.    
   
   
       10 . The abnormality determining apparatus according to  claim 1 , wherein 
 the bearing unit is used for a rotating member for supporting a railway wheel.