Abstract: In a vehicle steering system, when a sensor malfunction determination unit detects a malfunction of a rotation angle sensor, the sensor malfunction determination unit changes a control mode from a first control mode to a second control mode. In the second control mode, an actual rotor angle (mechanical angle) (?SM) of a steered system motor is computed on the basis of a second rotor angle (electric angle) (?SE2) estimated by a rotation angle estimation unit. Then, feedback control is executed such that the actual rotor angle (?SM) converges to a target rotor angle (?SM1*) that is obtained by superimposing a rotation maintaining command signal on a target rotor angle (?SM*) computed by a target rotor angle computation unit.

Abstract: A steering control apparatus includes a direct current power source, a three-phase alternating current motor, and a motor driving circuit. An emergency switching element is provided on at least two phases of a three-phase power supply line connected to the three-phase alternating current motor within the motor driving circuit, and the emergency switching element is turned off when an abnormality occurs such that the motor driving circuit is disconnected from the three-phase alternating current motor. The emergency switching element is a MOSFET, and the MOSFETs are provided in pairs in each of the two phases of the three-phase power supply line. Further, parasitic diodes of the pairs of MOSFETs are disposed in opposite orientations to each other.

Abstract: A driving force distribution control device, which is mounted on a vehicle including an engine configured to generate driving force for the vehicle, a transmission device configured to shift rotation of an output shaft of the engine by transmission ratios, and a driving force transmission system capable of transmitting output of the transmission device to main drive wheels and auxiliary drive wheels, includes: a control device configured to, when a rotational speed of the output shaft of the engine is in a range in which abnormal sound of the driving force transmission system due to pulsation of the driving force can be generated, set a torque value to a value capable of reducing the abnormal sound depending on the driving force; and a driving force transmitting device configured to transmit driving force depending on the set value to the auxiliary drive wheels.

Abstract: A driving force transmission apparatus includes: a housing having an inner peripheral spline portion; an inner shaft having an outer peripheral spline portion; a main clutch including first outer and inner clutch plates respectively engaged with the inner and outer peripheral spline portions; a cam mechanism generating pressing force for pressing the main clutch by relatively rotating a pair of cam members; and an electromagnetic clutch mechanism including an armature engaged with the inner peripheral spline portion and applying rotation force to the cam mechanism for relatively rotating the cam members through energization of an electromagnetic coil. An end face facing the armature is formed in the inner peripheral spline portion between a first region engaged with the first outer clutch plate and a second region engaged with the armature. Movement of the armature toward the first region is regulated by contact of the armature with the end face.

Abstract: An electric power steering apparatus includes a steering column that is swung around a tilting spindle during tilt adjustment, a fixing bracket that supports the steering column through the tilting spindle, and an electric motor that is supported by the steering column and used as a steering auxiliary. The fixing bracket includes a pair of side plates facing each other with the steering shaft therebetween in a vehicle width direction and a connection member through which the pair of side plates are connected together. Either one of the pair of side plates is provided with a first restraining portion that restrains the steering column from rotating in a first rotation direction around the tilting spindle. The remaining one of the pair of side plates is provided with a second restraining portion that restrains the steering column from rotating in a second rotation direction opposite to the first rotation direction.

Abstract: In an electric power steering system, rotation of a motor is transmitted to a rack shaft via a drive pulley, a belt, a driven pulley and a ball nut. A ball bearing and the driven pulley are fitted to the outer periphery of the ball nut. A flange is formed at a first end portion of the ball nut, and an internal thread portion is formed at a second end portion of the ball nut. An external thread member is connected to the internal thread portion. The external thread member has an external thread portion and a flange. By fastening the external thread portion to the internal thread portion, the ball bearing and the driven pulley are held between the two flanges.

Abstract: Portions of a pair of first pin members, a pair of second pin members, and a pair of third pin members other than one end portions thereof are respectively inserted into and held in a pair of first holding holes, a pair of second holding holes and a pair of third holding holes that extend perpendicularly to reference surfaces that are top faces of first to third connected body assembly jigs. In this state, a single first link plate, a single second link plate and a third link plate are press-fitted onto the one end portions until the first to third link plates come into contact with the reference surfaces. In this way, first to third multiple connected bodies are assembled. Then, the first to third multiple connected bodies and multiple fourth link plates are assembled into a power transmission chain.

Abstract: There is provided an actuator control apparatus configured such that even when an electronic device that generates an electric signal to be used to control an actuator is provided in the form of a duplexed system, an increase in the number of communication paths between the electronic device and a controller is suppressed. A torque sensor and a rotation angle sensor are each provided in the form of a duplexed system. Two sets of a torque sensor and a rotation angle sensor are connected to a microcomputer via a SPI communication line. The torque sensors and the rotation angle sensors are connected to the microcomputer via CS communication lines, respectively. By selecting a communication target via a corresponding one of the CS communication lines, the microcomputer is able to receive multiple kinds of electric signals via each one of the SPI communication lines.

Abstract: A ball nut of a steering system has an external thread portion at a first end portion, and a flange at a second end portion. A ball bearing, a flange member and a driven pulley are sandwiched between a locknut and the flange in the axial direction of the ball nut. As one of side portions of a belt abuts against the flange member or the flange, the belt is restrained from coming off the driven pulley.

Abstract: A method of manufacturing a grinding wheel, and a grinding wheel. After a first overcoat layer is formed on each of CBN abrasive grains, a second overcoat layer that is plastically deformed under a pressure lower than a pressure under which the first overcoat layer is deformed, is formed on the outer side of the first overcoat layer to manufacture coated abrasive grains. The coated abrasive grains are subjected to pressure-molding to be formed into a prescribed shape under a pressure that is equal to or higher than a pressure under which the second overcoat layer is plastically deformed. The second overcoat layers are deformed and flow to form a molded material having a structure in which the first overcoat layers contact each other, and the flowing second overcoat layers are moved into clearances between the coated abrasive grains.

Abstract: A steering system includes a column shaft that is supported by a column tube so that the column shaft is able to rotate. A male serration is formed in a lower end of a lower shaft of the column shaft in an axial direction. A universal joint connects the lower shaft with an intermediate shaft. A first portion of the male serration is fitted to a serration hole of a rotor of a steering angle sensor, and a second portion of the male serration is fitted to a serration hole of a first yoke of the universal joint.

Abstract: An electric power steering system calculates a motor resistance Rm using a resistance map, and calculates an estimated inducted voltage based on a motor current and a motor voltage. If the estimated induced voltage is determined as being equal to or smaller than a determination value that is set in accordance with the current level, the electric power steering system calculates a motor resistance (estimated motor resistance Rma) and updates the resistance map based on the estimated motor resistance Rma.

Abstract: A control unit that relatively moves a headstock and tailstock and a tool to thereby machine a peripheral surface of a workpiece in a radial direction executes control such that a relative feed speed of the tool in the radial direction in a transitional state where an amount of warpage of the workpiece in the radial direction at a machining position increases is faster than a relative feed speed of the tool in the radial direction in a steady state where an amount of warpage of the workpiece in the radial direction at the machining position is constant. By so doing, it is possible to reduce a machining time at the time of the start of machining.

Abstract: A clutch device includes; i) a clutch mechanism including a friction engagement member capable of rotating relative to a rotating member and a clutch member that is supplied with restoration force in a direction in which the clutch member departs from the friction engagement member by a restoration spring; and ii) a cam mechanism including; a cam member that is arranged in parallel to the clutch mechanism along a rotation axis line of the rotating member and that is incapable of rotating relative to the rotating member; and a cam follower capable of rolling on a cam surface that exists between the cam member and the clutch member. The cam angle is set to make torque applied to the clutch member due to reaction force accompanied by friction engagement with the friction engagement member larger than torque applied to the clutch member by thrust force caused by an activation of the cam mechanism.

Abstract: A power steering system includes an EPS and a HPS. At normal times, an assist force required by a steering system is computed based on a steering torque and a vehicle speed, and the required assist force is generated by the EPS and the HPS. The torsional stiffness of a torsion bar of the HPS is equal to or substantially equal to the torsional stiffness of a torsion bar of the EPS. Therefore, even if the EPS malfunctions, it is possible to gain the steering feel similar to that when the EPS is operating properly.

Abstract: An electric power steering system includes: a steered shaft, a housing containing the steered shaft therein in a movable manner; a ball screw nut engaged threadedly to the steered shaft via a plurality of balls and configured to move the steered shaft in an axial direction; a double row angular contact ball bearing configured to retain the ball screw nut and to support the retained ball screw nut rotatably relative to the housing; a wall portion placed at either side of the double row angular contact ball bearing in the axial direction of the steered shaft, the wall portion being formed integrally with the housing; and an elastic member provided between the wall portion and the outer ring portion and configured to retain the double row angular contact ball bearing to be elastically displaceable in the axial direction.

Abstract: A power transmission chain includes a plurality of link units which are aligned in a chain advancing direction, and each link unit includes a plurality of link plates which are aligned in a chain width direction W. The plurality of link plates include link plates which are punched out of a material by pressing to first and second specifications. A punching direction of the link plates to the first specification and a punching direction of the link plates to the second specification are made opposite to each other.

Abstract: A motor control device has characteristic information that indicates a correlation between a rotation speed and a current of a motor. The motor control device sets a rotation speed characteristic value that is a reference value of the rotation speed of the motor and a current characteristic value that is a reference value of the current of the motor on the basis of the characteristic information. The motor control device calculates an estimated rotation speed on the basis of a measured value of a voltage that is applied to the motor, a measured value of the current, the current characteristic value, a voltage characteristic value, the rotation speed characteristic value and a counter-electromotive force constant.

Abstract: An assisting command value calculating unit calculates a first assisting factor on the basis of the value of a torque differential control volume added to a basic assist control volume based on a steering torque value, while increasing or decreasing, on the basis of an assisting gradient, the torque differential control volume based on a torque differential value. The pinion angle F/B control unit calculates a pinion angle command value, capable of being converted to a steering angle of the steering wheel, on the basis of the steering torque and the first assisting factor, and executes rotational angle feedback control. The assisting command value calculating unit calculates an assisting command value on the basis of the value of a second assisting factor, calculated by the pinion angle F/B control unit, added to the first assisting factor.

Abstract: An electric power steering system includes elastic members arranged at respective axial ends of a first bearing by which a motor shaft that serves as a hollow shaft is rotatably supported and which elastically support the first bearing relative to a rack housing in the axial direction; and a support member disposed on the outer periphery of the first bearing to support the first bearing with displacement of the first bearing in the radial direction restricted. The motor shaft is disposed so as to move relative to the rack housing in the axial direction as the first bearing slides relative to the support member while elastically deforming the elastic members and a second bearing moves in the axial direction.