A bearing apparatus includes a lubrication unit and a sensor to sense the temperature of the lubricant in the lubrication unit. The lubrication unit has a pump having a storage portion in which the lubricant is stored and a piezoelectric body that is deformed by an applied voltage, the pump enabling the lubricant in the storage portion to be discharged into the annular space by reducing the volume of the storage portion in conjunction with the deformation of the piezoelectric body, the pump also enabling the lubricant to be sucked into the storage portion to refill the storage portion with the lubricant by increasing the volume of the storage portion, and a control unit that performs control by outputting a control signal allowing the speed of change in the volume of the storage portion to depend on the temperature of the lubricant.

A bearing assembly having a conductive medium. The bearing unit is mountable on a shaft and includes a bearing unit including a radially inner bearing ring including a radially inner race, wherein the radially inner bearing ring is rotatable with the shaft. The bearing unit further includes a radially outer bearing rings including a radially outer race, wherein the radially outer bearing ring is stationary with respect to the shaft; and a plurality of rolling elements supported to roll between the radially inner race of the radially inner bearing ring and the radially outer race of the radially outer bearing ring. An annular chamber body is disposed adjacent the bearing unit. A conductive medium is disposed within the chamber body.

A bearing apparatus includes a lubrication unit and a sensor to sense the temperature of the lubricant in the lubrication unit. The lubrication unit has a pump having a storage portion in which the lubricant is stored and a piezoelectric body that is deformed by an applied voltage, the pump enabling the lubricant in the storage portion to be discharged into the annular space by reducing the volume of the storage portion in conjunction with the deformation of the piezoelectric body, the pump also enabling the lubricant to be sucked into the storage portion to refill the storage portion with the lubricant by increasing the volume of the storage portion, and a control unit that performs control by outputting a control signal allowing the speed of change in the volume of the storage portion to depend on the temperature of the lubricant.