Abstract: A rolling bearing device includes: a bearing portion that has an inner ring, an outer ring, a plurality of balls, and a cage that holds the plurality of balls; and an oil supply unit that supplies lubricating oil to the bearing portion. The oil supply unit has: a pump that discharges the lubricating oil through drive of a piezo element; a voltage boost portion that boosts a voltage to be applied to the piezo element; and a control portion that causes the pump to operate while varying a voltage boost time included in a period since the start of voltage boost by the voltage boost portion until the start of the drive of the piezo element.

Abstract: A rolling bearing device includes a bearing portion and an oil supply unit provided adjacent, in the axial direction, to an annular space between an inner ring and an outer ring of the bearing portion to supply lubricating oil to the annular space. The oil supply unit includes an oil chamber that accommodates lubricating oil, a nozzle that discharges lubricating oil in the oil chamber, a pump body that applies a discharge force for causing lubricating oil in the oil chamber to fly from the nozzle toward the annular space, and a detection portion that detects gathering of lubricating oil at a discharge port of the nozzle. The detection portion includes a pair of electrodes disposed with the discharge port of the nozzle interposed therebetween, and a measurement portion that measures the capacitance of the pair of electrodes.

Abstract: A rolling bearing device includes: a bearing portion that has an inner ring, an outer ring, a plurality of balls interposed between the inner ring and the outer ring, and a cage that holds the plurality of balls; and an oil supply unit provided adjacent to the bearing portion in the axial direction. The oil supply unit has a pump configured to supply lubricating oil to the bearing portion. The pump has a pump body provided with a nozzle that discharges lubricating oil and a vibration element that vibrates the pump body.

Abstract: A pump included in an oil supply unit includes a piezoelectric body that is repeatedly deformed when a pulsed drive voltage is applied from a drive unit. The pump discharges lubricant as the volume of a storage unit that stores fluid to be supplied decreases with deformation of the piezoelectric body. An abnormal discharge detection device that detects an abnormal fluid discharge operation of the pump includes: a measurement unit that measures a terminal voltage of the piezoelectric body; and a control unit functioning as a determination unit that determines if the discharge operation is being performed normally or not based on whether or not the measured terminal voltage has changed with time during application of a pulse of the drive voltage.

Abstract: A control apparatus controls driving of an oil feeding unit. The oil feeding unit includes a piezoelectric body that deforms in response to a voltage applied thereto, and a reservoir to store lubricating oil. The capacity of the reservoir changes in accordance with deformation of the piezoelectric body so as to discharge lubricating oil from the oil feeding unit. The control apparatus includes N driving circuits 71a to 71n configured to apply voltages to the piezoelectric body (where N is an integer equal to or greater than two). The N driving circuits 71a to 71n are connected in parallel to the piezoelectric body. During oil feeding, the control apparatus uses a predetermined number of the driving circuits selected from the N driving circuits.

Abstract: A bearing device includes a bearing portion that includes an inner ring, an outer ring, a plurality of rolling elements that are interposed between the inner ring and the outer ring, and a cage that holds the plurality of rolling elements, one of the inner ring and the outer ring being a rotational ring, and another of the inner ring and the outer ring being a fixed ring; and an oil supply unit that is provided adjacent to the bearing portion in an axial direction. The cage includes a guide portion that is configured to be in sliding contact with a part of the fixed ring via lubricating oil. The oil supply unit includes a vibration sensor configured to detect a vibration of the fixed ring, and a pump configured to supply the lubricating oil to the bearing portion.

Abstract: 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.

Abstract: A rolling bearing apparatus includes a bearing main body having an outer ring that is a fixed ring and an inner ring that is a rotating ring, the outer ring and the inner ring being concentrically provided, and a plurality of rolling elements provided between the outer ring and the inner ring, and a control unit having a vibration detector attached to the outer ring and a calculation unit that calculates a value for vibration of the bearing main body and a rotation speed thereof based on a detection signal from the vibration detector. The calculation unit calculates the rotation speed based on frequency components of vibration obtained from the detection signal and the number of vibrations inherent in the bearing main body.

Abstract: A resolver stator includes an annular first cover portion, an annular second cover portion, and a plurality of pillars. The first and second cover portions cover coils from both axial sides. The pillars couple the first and second cover portions, and are arranged between the adjacent teeth. Each pillar has circumferential side faces each of which has a radially inner end portion that is arranged with a labyrinth clearance left between the radially inner end portion and a radially inner end portion of the tooth next to the side face, and each of which is a concave curved surface so as to be further apart from the tooth from the radially inner end portion toward a radially outer end portion of the side face.