Abstract: There is provided a drive control method for a motor including multiple sets of coils and drive circuits in an electric power steering system. In order to reduce computational load when sensorless control is executed, an electrical angle estimator includes an ?-axis voltage component adder and a ?-axis voltage component adder that add together voltage vectors of a first coil and a second coil expressed in a two-phase fixed coordinate system, an ?-axis current component adder and a ?-axis current component adder that add together current vectors of the first coil and the second coil expressed in a two-phase fixed coordinate system, and an induced voltage computing unit that computes an induced voltage based on an added voltage vector and an added current vector.

Abstract: A cage, which is annular, and is used in a thrust roller bearing, includes a plurality of cage segments arranged in a circumferential direction. Each of the cage segments includes an arc portion; and a bar portion that extends radially inward from the arc portion and that maintains a circumferential interval between rollers adjacent to each other. A groove portion extending along an axial direction is formed at each of end faces of the arc portions, the end faces facing each other in the circumferential direction. In the cage, elastic bodies are inserted into the groove portions and urge the arc portions in the circumferential direction, each of the elastic bodies is disposed between the end faces facing each other, and the cage segments are connected to each other by the elastic bodies.

Abstract: The control apparatus calculates the first assist component on the basis of the steering torque. The control apparatus calculates the turning angle command value from the steering torque and the first assist component on the basis of the ideal model, executes turning angle feedback control for matching the actual turning angle with the turning angle command value, and calculates the second assist component. The control apparatus adds the second assist component to the first assist component to calculate the assist command value. When the deviation between the actual turning angle and the turning angle command value is out of the allowable range, the control apparatus changes the ideal model to remove the second assist component from the assist command value and enhance convergence of the turning angle feedback control system.

Abstract: A pump rotation speed correcting unit includes a valve opening degree command differential value computing unit, a pump rotation speed correction value computing unit, and a correction value adding unit. The valve opening degree command differential value computing unit computes a temporal differential value of a valve opening degree command value that is set by a valve opening degree command value setting unit. The pump rotation speed correction value computing unit computes a correction value of a pump rotation speed command value on the basis of the valve opening degree command differential value. The correction value adding unit adds the pump rotation speed correction value to the pump rotation speed command value that is set by the pump rotation speed command value setting unit.

Abstract: A second shaft is configured by a shaft portion extending outside a housing in which a nutation gear mechanism is housed, a housing portion, and a cylindrical portion. A communicating hole, through which an outside and an inside of the housing portion communicate with each other, is formed in the shaft portion. A preload applying mechanism includes a preload adjusting plug that is screwed to the housing portion and is able to be operated from outside through the communicating hole, a wave washer compressed in accordance with a position of the preload adjusting plug, and a lock nut that is screwed to the housing portion of the second shaft so as to press the preload adjusting plug toward the nutation gear mechanism.

Abstract: A core grinding wheel that has a grinding layer on an outer periphery of a core is used. An ultrasonic wave is output from an ultrasonic sensor to the grinding layer via grinding fluid. An ultrasonic measuring device control unit calculates a thickness of the grinding layer on the basis of a sonic velocity in the grinding layer and an arrival time difference between a reflected wave from a surface of the grinding layer and a reflected wave from a surface of the outer periphery of the core. A grinding process and a truing process are controlled on the basis of an outside diameter of the grinding wheel, which is calculated on the basis of the measured thickness of the grinding layer and an outside diameter of the core.

Abstract: The electrical power steering apparatus 10 includes the 1st MOS-FET 13 and the 2nd MOS-FET 14 accommodating the 1st parasitic diode 15 and the 2nd parasitic diode 16 in the conducting path between the battery 100 and the motor driving circuit 11 and being connected in series at the opposite direction respectively, and the condenser 18 in an output side of the latter 2nd MOS-FET 14. The ECU 6 of the controller of the electrical power steering apparatus controls to turn on or off the 1st MOS-FET 13 and the 2nd MOS-FET 14 in accordance with the predetermined sequence after the ignition switch 17 is turned on, detecting the fault of the 1st MOS-FET 13, the 2nd MOS-FET 14 and the 1st parasitic diode 15 and the 2nd parasitic diode 16 on the basis of the output voltage from each of the 1st MOS-FET 13 and the 2nd MOS-FET 14.

Abstract: A sliding member includes a base material portion formed of steel; a nitrogen diffusion layer with a thickness of 10 ?m to 50 ?m; and a nitrogen compound layer with a thickness of 10 ?m to 50 ?m. The nitrogen compound layer and the nitrogen diffusion layer are formed by performing a first heating process of performing heat treatment on a material formed of steel in an ammonia atmosphere at a temperature of 570° C. to 660° C., a second heating process of performing heat treatment on the material in a non-oxidizing and non-ammonia atmosphere at a temperature of 660° C. to 690° C., the temperature in the second heating process being higher than the temperature in the first heating process, and an oil cooling process of performing oil cooling treatment at an oil temperature of 60° C. to 80° C. subsequently to the second heating process.

Abstract: A rolling bearing unit includes: a rolling bearing having an inner ring, an outer ring arranged, multiple rolling elements, and a cage; and a cage guide member that is formed integrally with the outer ring or formed as a member different from the outer ring, and that is fixed to the housing side. The cage guide member has a guide projection projected into an annular space between the inner and outer rings and having an outer peripheral face a part of which serves as the guide face, and a grease supply portion having a grease reservoir portion in which the grease is reserved. A supply port through which the grease is supplied from the grease reservoir portion to the guide face is formed on the outer peripheral face of the guide projection, at a position closer to a base end portion of the guide projection than the guide face.

Abstract: A motor control apparatus includes a plurality of voltage detecting sections configured to each detect a terminal voltage of one of phases of a brushless motor, and a control section configured to control driving of the motor. The control section takes in, via separate signal lines, detection signals of the voltage detecting sections. When the condition that any two of terminal voltage detection values of respective phases obtained from the detection signals of the voltage detecting sections are continuously equal to each other is satisfied, the control section determines that a short circuit has occurred between any of the signal lines.

Abstract: An electric power steering device includes: a worm shaft including a first end portion and a second end portion; a worm wheel; a joint; and an urging member. The first end portion includes: a first tubular portion; a diameter enlargement permission portion to allow enlargement of a diameter of the first tubular portion; and an external teeth portion. The joint includes: a second tubular portion; and an internal teeth portion capable of engaging the external teeth portion. The electric power steering device further includes a diameter enlargement member which is arranged in the first tubular portion and which enlarges a part of the first tubular portion in an axial direction thereof to press the internal teeth portion toward the external teeth portion.

Abstract: A relative movement trajectory of each convex tooth pin of a mating gear with respect to a concave-convex gear at the time when torque is transmitted between the mating gear and the concave-convex gear (nutation gear) may be expressed by a first linear axis, a second linear axis, a third linear axis, a fourth rotation axis, a fifth rotation axis and a sixth indexing axis. Then, a relative movement trajectory of each convex tooth pin of the mating gear, expressed by the first linear axis, the second linear axis, the third linear axis, the fifth rotation axis and the sixth indexing axis in the case where the fourth rotation axis is brought into coincidence with the sixth indexing axis, is calculated, and at least one of a disc-shaped workpiece and a working tool is moved on the basis of the calculated relative movement trajectory.

Abstract: First and second lower support mechanisms (27, 28): are each provided with a coil spring (66, 86) that is mated to the outer periphery of an axle part (59, 79) of a fulcrum bolt (53, 73); and are configured in such a manner that support brackets (51, 71) are able to rock with respect to a steering column (5) by compressing the coil springs (66, 86). The coil springs (66, 86) are formed in such a manner that the axle parts (59, 79) are force fitted in a state prior to column-side fastening parts (55, 75) being fastened to the steering column (5).

Abstract: A motor control signal output unit of an electric power steering system includes a feedback gain calculation unit (52), and a feedback control unit executes a feedback control with the use of a proportional gain (Kp) and an integral gain (Ki) that are calculated by the feedback gain calculation unit (52). The feedback gain calculation unit (52) sets the feedback gains to large values (Kp=P0, Ki=I0) when the absolute value of an assist gradient (?) is equal to or smaller than a predetermined value (?0) (|?|??0). On the other hand, when the absolute value of the assist gradient (?) exceeds the predetermined value (?0) (|?|>?0), the feedback gain calculation unit (52) sets the feedback gains to small values (Kp=p1, Ki=I1:P1<P0, I1<I0).

Abstract: In an abnormality detection system for a rotation angle sensor, a fact that an abnormality has occurred in one of sine signals (S1, S2) or in one of cosine signals (S3, S4) is detected based on a sum of the electrical signals (S1, S2), and a sum of the electrical signals (S3, S4) (first detection result). A fact that an abnormality has occurred in one of the positive sine and cosine signals (S1, S3) or in one of the negative sine and cosine signals (S2, S4) by comparing a first temperature computed using a correlation between an amplitude and a temperature and based on the electrical signals (S1, S3), a second temperature computed using a correlation between the amplitude and a temperature and based on the electrical signals (S2, S4), and a third temperature detected by a temperature sensor with each other (second detection result). A microcomputer identifies which of the electrical signals is abnormal by comparing the first and second detection results with each other.

Abstract: In a manufacturing method for a hollow rack shaft, and a hollow rack shaft, a tubular member (23) having a planar flat portion (22) that is formed in part of a tubular body portion (21) is sandwiched and held between a cope (25) and a drag (26) that has a tooth-shaped portion (29) substantially symmetrical with rack teeth (7) so that a surface (22a) of the flat portion (22) is in contact with the tooth-shaped portion (29). A back die (14) having a plurality of protrusions (15) is arranged so that the protrusions (15) face groove portions (29a) of the tooth-shaped portion (29) across the flat portion (22), and the back die (14) is pressed against the flat portion (22) to form the rack teeth (7) to thereby manufacture the rack shaft.

Abstract: A rolling bearing includes an inner ring, an outer rind and a plurality of rolling elements. Multiple dynamic pressure generating grooves are formed in at least one of an inner ring raceway surface and an outer ring raceway surface so as to be arranged at equal intervals in the circumferential direction. The number of the dynamic pressure generating grooves and the number of the rolling elements are set so as to establish a relationship expressed by A=[{n+(n+1)}/2]·Z, where A is the number of the dynamic pressure generating grooves, Z is the number of the rolling elements, and n is a natural number (1, 2, 3 . . . ).

Abstract: An axle bearing system includes a bearing portion which includes an inner ring, an outer ring and a plurality of rolling elements which are interposed between the inner ring and the outer ring and which is installed on a hub shaft with seal portions which are each formed by a slinger, a core metal and a non-conductive seal provided therebetween mounted in annular opening portions formed between the inner ring and the outer ring. A conductive body is attached to the seal portion so as to provide an electrical conducting state between the outer ring and the inner ring.

Abstract: A split cage for a rolling bearing includes a plurality of cage segments formed of synthetic resin and arranged annularly in a circumferential direction. Each cage segment includes: a first rim portion and a second rim portion that are spaced from each other by a predetermined interval and face each other; and a plurality of bar portions extending from the first rim portion to the second rim portion. Spaces, each of which is surrounded by the bar portions adjacent to each other and the first and second rim portions, are formed as pockets that house rolling elements. Projections for reinforcement are formed at radial end portions of boundaries between the bar portions and the first rim portion and/or boundaries between the bar portions and the second rim portion.

Abstract: A rotary dresser is provided with a roll having an outer circumferential surface which includes an arc portion or inclined portion differing in diameter in dependence on the axial position thereof, and a plurality of diamond abrasive grains embedded on the outer circumferential surface of the roll. The number of the diamond abrasive grains in the circumferential direction is fixed even at any axial position on the outer circumferential surface of the roll.