Abstract: A motor rotor has: a rotor yoke; a plurality of magnet fixing sections formed on the lateral surface of the rotor yoke; segment magnets respectively fixed to the magnet fixing sections and extending in the axial direction of the rotor yoke; and a plurality of projections which are provided, on the rotor yoke, at each boundary section located between each of the adjacent magnet mounting sections, and which protrude outward from the rotor yoke; and a pair of end claws are formed by bifurcating the end of each projection into two prongs, and each of the end claws is locked to the outer surface of each of the segment magnets.

Abstract: A main spindle device includes: a housing having an air supply passage; a spindle that is inserted into the housing and supported by a bearing so as to be able to rotate relative to the housing; and an air sealing member that is positioned between an outer circumferential surface of the spindle and the housing on a front side with respect to the bearing along a rotation axis of the spindle, has a substantially annular shape, and is detachably fixed to the housing with an inner circumferential surface of the air sealing member facing the outer circumferential surface of the spindle, wherein air supplied from the air supply source through the air supply passage is discharged into a gap between the outer circumferential surface of the spindle and the housing, thereby effecting non-contact air sealing at least between the inner circumferential surface of the air sealing member and the outer circumferential surface of the spindle.

Abstract: An electric power steering apparatus (1, 64) comprises a housing (10) for supporting a steer shaft (9) for axial slide movement, a speed reduction mechanism (23), and a motion converting mechanism (24, 76). The housing (10) includes a plurality of split housings (36, 37; 36, 37A, 70) connected to each other. The speed reduction mechanism (23) includes an output gear (22) surrounding the steer shaft (9). The motion converting mechanism (24, 76) includes a rotary sleeve (28) surrounding the steer shaft (9) and rotatable integrally with the output gear (22) and converts the rotation of the rotary sleeve (28) into axial movement of the steer shaft (9). The rotary sleeve (28) is rotatably supported by first and second bearings (30, 31) disposed on opposite sides of the output gear (22). The split housings (36, 37; 36, 37A, 70) include main split housings (37, 37A) rotatably supporting an input gear (21) and supporting the first and second bearings (30, 31).

Abstract: A vehicle steering apparatus includes a steering member; a steering shaft connected to the steering member; a torque sensor for detecting a steering torque inputted into the steering member; and an electric motor for generating power that is transmitted to the steering shaft based on the steering torque detected by the torque sensor. The electric motor includes an annular rotor and an annular stator. The annular rotor includes an annular rotor core which coaxially surrounds the steering shaft and is rotatable together with a part of the steering shaft. An annular accommodation space is formed between an outer circumference of the steering shaft and an inner circumference of the annular rotor core, and at least a part of the torque sensor is disposed within the annular accommodation space.

Abstract: An electric power steering system is provided which is capable of providing a favorable steering feeling without using compensation logics such as of inertia compensation and friction compensation. The electric power steering system includes road-noise suppression control means (213) for controlling a steering assist motor (9) in a manner to damp torque transmission in a higher frequency region representing road noises than a frequency region representing road information. A friction value of a steering mechanism (A) is decreased enough to allow the intrinsic vibrations of the steering mechanism (A) to appear. Rotor inertia of the steering assist motor (9) is set to a value small enough to allow the frequencies of the intrinsic vibrations to be present in the frequency region where the torque transmission is damped by the road-noise suppression control means (213).

Abstract: If the magnitude of a command voltage vector is greater than a predetermined voltage value indicated by a voltage limit circle, the magnitude of a voltage vector, which corresponds to a q-axis current and which forms the command voltage vector, is adjusted so that the magnitude of the command voltage vector is equal to or less than the predetermined voltage value. Then a q-axis current estimated value is obtained based on i) the ratio of the magnitude of the voltage vector from the q-axis current after adjustment to the magnitude of the voltage vector from the q-axis current before adjustment, and ii) a q-axis current command value.

Abstract: In a ball screw mechanism, a retainer is provided between an outer circumference of a ball screw shaft and an inner circumference of a ball nut and has a plurality of retainer grooves arranged in the circumferential direction for retaining a plurality of rolling balls. Each retainer groove of the retainer takes a form that allows the rolling balls therein to move radially outward but restrains the rolling balls therein from moving radially inward. Therefore, in the ball screw mechanism and an electric power steering device incorporating the same, the movement of the retainer in radial directions can be restricted by the plurality of rolling balls which are rolled along ball rolling grooves spirally formed respectively on the outer circumference of the ball screw shaft and the inner circumference of the ball nut.

Abstract: A grinding machine is provided with first and second grinding wheels selectively used in dependence on the steps of machining operations. The second grinding wheel is grooved so that at least one oblique groove vertically crosses a contact surface on which a grinding surface of the second grinding wheel contacts with a workpiece, and thus, is capable of releasing a dynamic pressure in coolant generated between the grinding surface and the workpiece since coolant supplied from over the contact surface flows out from both of the upper and lower sides of the contact surface through the at least one oblique groove. Since it does not occur that fluctuations in the dynamic pressure generated in coolant cause the distance between the second grinding wheel and the workpiece to be varied, the accuracy in grinding the workpiece with the second grinding wheel can be enhanced.

Abstract: To provide a motor control apparatus, including a rotational number detecting means for detecting the rotational number of a motor; a current detecting means for detecting a motor current; a voltage detecting means for detecting an impressed voltage to be supplied to a motor; a temperature estimating means for obtaining a motor temperature from the rotational number of a motor, the motor current, and the impressed voltage; and a protection signal generating means for generating an operational signal in order to protect the motor when the obtained motor temperature exceeds a predetermined value.

Abstract: An abnormality judging apparatus of a rotation angle detecting apparatus generating a sine wave signal and a cosine wave signal according to the rotation angle of a rotor is provided with an interface which receives the sine wave signal, an interface which receives the cosine wave signal, a signal arithmetic circuit which successively calculates the sum of each square of the received sine wave signal and cosine wave signal, a memory which stores as a threshold value the value of the sum of each square of the sine wave signal and cosine wave signal received from the rotation angle detecting apparatus at a predetermined point in time, and a judging circuit which judges that abnormality has occurred at the rotation angle detecting apparatus when the difference between the value calculated by the signal arithmetic circuit and the value stored in the memory is out of a predetermined range.

Abstract: A suspension control device includes a wheel grip state estimation device for estimating grip state of vehicle wheels based on variations of aligning torque of wheels to be steered, a vehicle rolling control device for controlling vehicle rolling, and a control parameter setting device for setting a control parameter of the vehicle rolling control device based on at least estimated grip state of the wheel grip state estimation device.

Abstract: The invention provides a motor-driven power steering apparatus which can achieve a predetermined speed reduction ratio even in the case that the motor-driven power steering apparatus is constituted by a pair of spur gears or helical gears, and can secure a sufficient gear strength on the basis of a simple structure. In a motor-driven power steering apparatus in which a rotating torque of an electric motor (7) is transmitted to a steering shaft by a drive gear (6) provided in an output shaft of the electric motor (7) and a driven gear (5) provided in the steering shaft, and a speed reduction ratio is equal to or more than 3, the steering shaft and the output shaft of the electric motor (7) are arranged in almost parallel, a center distance between both the shafts is equal to or more than 35 mm and equal to or less than 90 mm, and the drive gear (6) is configured such that a number of teeth is equal to or more than 6 and equal to or less than 15, a module is equal to or more than 0.

Abstract: A rolling bearing assembly for a wheel includes: an inner ring member in which an inner ring raceway surface is formed on an outer peripheral surface of the inner ring member; an outer ring member having a fitting tubular portion on the inboard side that is fitted into an attachment hole of a vehicle body member, and an outer ring raceway surface is formed on an inner peripheral surface of the outer ring member; a plurality of rolling elements disposed between the inner and outer ring raceway surfaces; and a cage that holds the plurality of rolling elements. The bore diameter B of the fitting tubular portion of the outer ring member is smaller than the diameter C of a circumscribed circle of the rolling elements.

Abstract: In a wheel bearing assembly, an outer surface of a head portion of a link bolt contacts an inner surface of an end wall portion of a constant-velocity joint outer ring. A shaft portion of a link bolt is press-fit into a penetration hole of the constant-velocity joint outer ring. An external threaded portion of the link bolt is inserted into the central hole of a hub spindle so that the external threaded portion protrudes from an outer end surface of a hub wheel. A lock nut is fastened to the external threaded portion, so that the wheel hub and the constant-velocity joint outer ring are linked, and the first spline and the second spline are meshed so as to be capable of torque transmission.

Abstract: A tapered roller bearing apparatus includes: an outer ring that includes an outer-ring raceway formed in an inner circumferential surface thereof; an inner ring which includes a large-diameter portion having a cylindrical portion with a substantially uniform outer diameter, a large rib portion having an outer circumferential surface and a guide surface continued to the outer circumferential surface, an inner-ring raceway, and a small-diameter cylindrical portion which are sequentially formed from one end to the other end, and are subjected to a heat treatment to have a surface-hardened layer; and a plurality of tapered rollers which are rollably disposed between the inner-ring raceway and the outer-ring raceway, a large-diameter end surface of the tapered roller being guided by the guide surface. An angle formed between the guide surface and the outer circumferential surface is obtuse.

Abstract: A skew contact double row ball bearing and a bearing device for supporting a pinion shaft. The skew contact double row ball bearing enabling the simultaneous contact of a ball row in each row on raceways at a specified contact angle when installed even if a clearance amount is reduced by the fitting of the bearing by preventing the ball bearing from being substantially affected by a change in the assembled width of each row by the fitting of the bearing. The axially double row ball rows are interposed between the raceways of inner and outer rings and at pitch circle diameters different from each other and at contact angles different from each other so that the radial clearance of the ball row with the smaller contact angle is set larger than the radial clearance of the ball row with the larger contact angle.

Abstract: When determining that a vehicle is not skidding, the ECU carries out tight corner control if vehicle speed is smaller than the upper limit value of the vehicle speed range corresponding to the starting state of the vehicle and the steering wheel turning angle of a steering wheel is greater than or equal to the minimum value of the steering wheel turning angle at which the tight corner braking phenomenon may occur. When determining that the vehicle is skidding, the ECU inhibits the tight corner control even if the vehicle speed is smaller than the upper limit value and the steering wheel turning angle is greater than or equal to the minimum value of the steering wheel turning angle at which the tight corner braking phenomenon may occur.

Abstract: A post-process sizing control device is provided with origin compensation means for controlling a size measuring device to measure an actual size of a workpiece portion and for compensating the origin of a wheel head by a position compensation amount which corresponds to a difference between the actual size and a theoretical size derived from calculation and size measuring interval setting means for setting the number of workpieces which should be ground during the next size measuring interval which begins after the preceding origin compensation operation and ends with the next origin compensation operation. The size measuring interval setting means sets the number of workpieces which should be ground during the next size measuring interval, based on an average position compensation amount derived by dividing a position compensation amount for the last workpiece ground during the present size measuring interval by the number of workpieces ground during the present size measuring interval.

Abstract: A wheel bearing assembly includes i) a wheel hub having a hub spindle, a central hole formed the hub spindle, and female splines formed extending in the axial direction on an inner peripheral surface of the central hole, and ii) a constant velocity joint outer ring having a protruding central shaft and male splines formed extending in the axial direction on an outer peripheral surface of the central shaft. The wheel hub and the constant velocity joint outer ring are splined together by the male splines and the female splines fitting together, and a seal layer made of an anaerobic sealant that seals a gap at a meshing area where the male splines and the female splines mesh together is provided at that meshing area.