Abstract: A production method of a ball screw device is provided. The ball screw device includes a ball screw portion, a ball nut, rolling balls, and a retainer. The production method of the ball screw device includes: a first preparation step of preparing a nut subassembly as a standard product; a second preparation step of preparing the ball screw portion in plurality by types as ranked products; a measuring step of measuring a relative displacement in a thrust direction between the standard product and each ranked product; a determination step of determining whether the displacement meets a displacement specification; a replacing step of, if the displacement does not meet the specification, replacing the ranked product with another ranked product; and an assembling step of, if the displacement meets the specification, assembling the standard product and the ranked product into the ball screw device.

Abstract: A pressure reducing valve includes a body, an annular valve seat, a valve element, and a pressing mechanism configured to press the valve element. The pressing mechanism includes a plug provided downstream of the valve seat and having a plug hole, and a pin including a sliding portion and an upstream end, the sliding portion having a shaft shape and being inserted in the plug hole such that a gap is provided between the sliding portion and an inner peripheral surface of the plug hole, and the upstream end being provided upstream of the sliding portion so as to contact the valve element. A fitting length of the sliding portion with respect to the plug hole and the gap between the sliding portion and the plug hole satisfy 0.0005 L<C<0.00908 L, where L indicates the fitting length, and C indicates the gap.

Abstract: A steering control apparatus for a steering system includes a controller. The controller sets a limit value to less than or equal to a steering angle limit value, the limit value being an upper limit of an absolute value of a torque command value, and controls a motor such that a motor torque follows the torque command. When the absolute value of a rotation angle of a rotary shaft exceeds a steering angle threshold, the controller computes a damping control amount such that the damping control amount increases with an increase in an excess of an angular velocity of the rotary shaft over a first upper limit angular velocity. The controller computes the torque command value based on a value obtained by combining the basic command value and the damping control amount such that an absolute value of the basic command value is reduced.

Abstract: A walking assist device has a frame, a pair of right and left arm portions, a pair of right and left grasp portions, wheels including a pair of right and left drive wheels, drive units, a battery, a drive control unit, acting force measurement units that measure acting forces on the grasp portions, and holding units that hold the grasp portions at a predetermined position in the front-rear direction of the arm portions set in advance. The walking assist device travels forward together with a user. The holding units generate a restoring force for returning the grasp portions to the predetermined position. The drive control unit controls the drive units on the basis of acting forces calculated on the basis of detection signals from the acting force measurement units.

Abstract: A rolling bearing includes an inner ring, an outer ring, a plurality of balls, and an annular cage that holds the balls at intervals in a circumferential direction. The cage has an annular portion on a first side in an axial direction, and a plurality of cage bars. Pockets that hold the respective balls are each formed between a pair of the cage bars adjacent to each other in the circumferential direction on a second side in the axial direction with respect to the annular portion. Each of the pockets has a pocket surface shaped along a cylindrical surface centered around a center line that is a virtual line extending in a bearing radial direction. A linear protrusion that is elongate in a direction parallel to the center line is provided at an axially-first-side bottom portion of the pocket surface.

Abstract: In a self-aligning roller bearing, in a longitudinal section including a center line of a spherical roller and an axis of the self-aligning roller bearing, a clearance X between an outer end surface of a spherical roller on an axially outer side of the self-aligning roller bearing and a rib portion, and a clearance Y between an inner end surface of the spherical roller on an axially inner side of the self-aligning roller bearing and a guide ring have a relation of X<Y.

Abstract: A control device controls a driving force transmission device that presses a main clutch using an actuator that generates a pressing force according to a supply current. The control device includes a current command value setting unit that sets a current command value based on I-T characteristic information indicating the relationship between a current supplied to the actuator and a driving force transmitted, a correction duration setting unit that sets a correction duration based on a responsiveness related value related to the responsiveness of the main clutch when an increase in the driving force to be transmitted by the main clutch becomes greater than or equal to a threshold, a correction unit that increases and corrects the current command value for the set correction duration, and the current control unit that performs current feedback control such that a current corresponding to the current command value is supplied to the actuator.

Abstract: A planetary roller power transmission device includes: a stationary ring; a sun shaft disposed radially inside the stationary ring so as to be concentric with an axis of the stationary ring; planetary rollers provided between the stationary ring and the sun shaft so as to be pressed against them; a carrier that rotatably supports the respective planetary rollers and rotates in conjunction with revolution of the planetary rollers; an oil-containing roller configured to be in contact with a peripheral surface of each planetary roller; and a support body having a support shaft that is formed to protrude toward one side in an axial direction of the stationary ring in a cantilevered manner and rotatably supports the oil-containing roller. An axis of the support shaft is inclined such that a distal end of the support shaft is closer to the axis of the stationary ring than a base end thereof.

Abstract: A rolling bearing includes: an inner ring; an outer ring; and a plurality of rolling elements provided between the inner ring and the outer ring, wherein: one of the inner ring and the outer ring is a rotating ring; the other one of the inner ring and the outer ring is a firm ring; the firm ring is attached to a prescribed member; and a black oxide film having a mesh-shaped crack is formed on at least one surface of a fitting surface of the firm ring and a side face of the firm ring, the fitting surface facing the prescribed member in a radial direction of the rolling bearing, the side face making contact with the prescribed member in an axial direction of the rolling bearing.

Abstract: There is provided a steering system that can absorb an increased total amount of shock at a time of a secondary collision. A steering member is connected to one end of an upper jacket in a column axial direction. A lower jacket is externally fitted with the other end of the upper jacket in the column axial direction so as to be slidable with respect to the upper jacket. The lower jacket is supported by a support member fixed to a vehicle body. At the time of a secondary collision, a first sliding member generates a first resistive force by performing first relative sliding with respect to the upper jacket, and a second sliding member which is moved together with the first sliding member in the column axial direction generates a second resistive force by performing second relative sliding with respect to the support member and the lower jacket.

Abstract: A tapered roller bearing includes an inner ring including, on its outer circumferential surface, an inner raceway surface and including, on an end portion on a second axial side, a cone back face rib portion protruding radially outward, an outer ring including, on its inner circumferential surface, an outer raceway surface, a plurality of tapered rollers disposed between the inner ring and the outer ring, and an annular cage that retains the plurality of tapered rollers spaced from each other in a circumferential direction. The cage includes a small-diameter annular portion, a large-diameter annular portion located on the second axial side relative to the tapered rollers and the outer ring, and a plurality of cage bar portions. The large-diameter annular portion has an oil pocket having a first aperture that is open radially inward and a second aperture that is open toward the outer raceway surface.

Abstract: A tapered roller bearing includes an inner ring, an outer ring, a plurality of tapered rollers, and an annular cage that holds the tapered rollers. The cage has a small annular portion positioned toward the axially first side with respect to the tapered rollers, a large annular portion positioned toward the axially second side with respect to the tapered rollers, and a plurality of cage bars that couples the small annular portion and the large annular portion together, and the cage is enabled to come into contact with an inner peripheral surface of the outer ring so that the contact allows the cage to be positioned in a radial direction. The small annular portion is provided with introduction channels through which lubricant is enabled to be introduced from a bearing exterior on the axially first side into an annular space formed between the inner and outer rings.

Abstract: A motor control device includes: a PWM count computation unit that computes a PWM count for each of three phases for each current control cycle; a PWM count setting unit that sets the PWM count for each phase in the current control cycle as a PWM count for each PWM cycle in the relevant current control cycle for the corresponding phase; and a common mode noise reduction unit that changes the PWM count in a PWM cycle for at least one phase, of two of the three phases other than one particular phase, such that a current that flows through a stray capacitance because of an output voltage for the one particular phase is canceled out with a current flowing through the stray capacitance because of an output voltage for the at least one of the two other phases in at least one PWM cycle in the current control cycle.

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: An auxiliary drive device includes: a drive unit that has an electric motor; a meshing clutch that has a first meshing member and a second meshing member; an actuator that moves the second meshing member; and a control unit that controls the electric motor and the actuator. The actuator moves the second meshing member among a separation position, at which the second meshing member is not meshed with the first meshing member, an abutment position, at which first meshing teeth and second meshing teeth possibly abut against each other, and a meshing position, at which the first meshing teeth and the second meshing teeth are meshed with each other. The control unit makes a current supplied to the electric motor when the second meshing member is located between the abutment position and the meshing position smaller than a current required to maintain the rotational speed of the electric motor.

Abstract: A bearing device includes: a first outer ring member and a second outer ring member which include a raceway surface in each inner circumferential surface and are disposed to abut on each other in an axial direction; a connection ring which fixes the first outer ring member and the second outer ring member to each other; an inner ring in which two rows of raceway surfaces are formed in an outer circumferential surface; and a plurality of rolling elements which are disposed in a space formed between the raceway surface of the first outer ring member and one of the two rows of the raceway surfaces of the inner ring, and in a space formed between the raceway surface of the second outer ring member and the other one of the two rows of the raceway surfaces of the inner ring.

Abstract: A method for manufacturing a wheel including a step (a) during which a liquid to be polymerised is cast into a first mould so as to solidify same into a tubular preform, with main axis, the first mould including modelling cores in order to form recesses, of the rib type, in the radial thickness of the tubular preform; followed by a cutting step (b), during which the tubular preform is cut perpendicular to the main axis thereof, and secant to the recesses, so as to obtain a tubular preform section forming a rim; followed by an overmoulding step (d), during which said rim is placed in a second mould, concentrically with a central supporting member, such as a bushing or a shaft, and a polymer filling material is injected so as to create an intermediate disc that provides the attachment of the rim to the central supporting member.

Abstract: A rolling bearing includes an inner ring, an outer ring, a plurality of balls, and a cage that holds the balls. An annular groove for creep suppression is formed in a fitting surface that is fitted on a housing to which an outer ring is attached. The annular groove has a groove bottom portion and a pair of tapered surface portions extending from opposite sides of the groove bottom portion in an axial direction and defining a groove width that is larger toward the fitting surface. In a section including a bearing center line, each of the tapered surface portions has a linear sectional shape inclined to the fitting surface.

Abstract: An apparatus for controlling a four-wheel drive vehicle includes a tire friction circle calculator that calculates the size of a tire friction circle of each wheel on the basis of vehicle information including a tire vertical load, a resultant force calculator that calculates the magnitude of a resultant force of tire lateral and longitudinal forces for each wheel, a tire-friction-force usage rate calculator that calculates a tire-friction-force usage rate of each wheel that is the ratio of the magnitude of the resultant force to the size of the tire friction circle, and a driving-braking force adjustment controller that adjusts driving force or braking force applied to each wheel.

Abstract: A steering apparatus includes a steering shaft; a steered shaft; a ball screw mechanism; and a motor. A plurality of rolling elements includes large-diameter rolling elements and small-diameter rolling elements. A prescribed diameter difference is set such that when a magnitude of power transmitted between a first screw groove and a second screw groove is a prescribed value or less, only the large-diameter rolling elements transmit the power between the first screw groove and the second screw groove, and when the magnitude of the power transmitted between the first screw groove and the second screw groove exceeds the prescribed value, both the large-diameter rolling elements and the small-diameter rolling elements transmit the power.