Abstract: A driving force transmitting apparatus is provided which enables rotational resistance of rotating members to be suppressed while sufficiently supplying lubricant to a friction clutch. A driving force transmitting apparatus includes a clutch drum having a cylindrical portion, an inner shaft having an end housed in the clutch drum, a friction clutch having outer clutch plates that rotate along with the clutch drum and inner clutch plates that rotate along with the inner shaft, a piston that presses the friction clutch, and a housing in which a first housing chamber housing the friction clutch is formed and in which a storage chamber storing lubricant scooped up by rotation of the clutch drum is also formed. The lubricant stored in the storage chamber returns to the first housing chamber through an inner circulation path leading to inside the clutch drum and an outer circulation path leading to outside the clutch drum.

Abstract: A cage has an annular portion positioned on an axially first side of balls and a plurality of cage bars provided to extend from the annular portion toward an axially second side. Pockets each housing a corresponding one of the balls correspond to areas each located on the axially second side of the annular portion and between two cage bars adjacent to each other in a circumferential direction. Each of the balls is exposed from axially-second-side ends of the corresponding cage bars over an axially-second-side range. An axial dimension of the range over which the ball is exposed from the axially-second-side ends is 30% or more and 50% or less of the diameter of the ball.

Abstract: A spline telescoping shaft includes an inner shaft including a male spline and a tubular outer shaft including a female spline. A resin film is provided on a surface of at least either of both the splines. An addendum modification coefficient e, the number of teeth Z, a module m, a reference pitch circle diameter PCD, a tip circle diameter d1 and a root circle diameter d2 of the male spline and a tip circle diameter D1 and a root circle diameter D2 of the female spline have relations expressed by expressions (1) to (8). m(Z+4)>d1>m(Z+2)??(1), mZ>d2>m(Z?1)??(2), m(Z+4)>D2>m(Z+2)??(3), mZ>D1>m(Z?1)??(4), D2>d1??(5), D1>d2??(6), PCD=mZ??(7), and 0.4<e<1.

Abstract: A bearing ring includes a raceway surface on which a roller of a roller bearing rolls, a rib portion end face that is provided on one side of the raceway surface in an axial direction and that faces a roller end face of the roller in which at least an outer circumferential side of the roller end face is a convex curved surface portion, and a recessed portion having a recessed shape provided in a corner between the raceway surface and the rib portion end face. The rib portion end face includes a contacting surface portion that the roller end face contacts, and a concave curved surface portion that is provided between the contacting surface portion and the recessed portion and that is smoothly continuous with the contacting surface portion. A curvature radius of the concave curved surface portion is greater than that of the convex curved surface portion.

Abstract: A grinding wheel includes a disc-like member and a grinding layer disposed on an outer peripheral surface of the disc-like member. The grinding layer includes a plurality of circumferentially-divided grinding chips which are divided in a circumferential direction. Each of the circumferentially-divided grinding chips is formed by arranging a first grinding chip and a second grinding chip in the axis direction, the first grinding chip and the second grinding chip having different properties. A boundary portion between the first grinding chip and the second grinding chip of at least three circumferentially-divided grinding chips continuously arranged in the circumferential direction are arranged toward a predetermined direction in the axis direction in the order in which the circumferentially-divided grinding chips are arranged.

Abstract: A drive force transmission apparatus is mountable on a four-wheel drive vehicle switchable between a four-wheel drive mode that transmits a drive force of an engine to front wheels and rear wheels, and a two-wheel drive mode that transmits the drive force to only the front wheels. The drive force transmission apparatus allows adjustment of the drive force to the rear wheels, and includes a multi-plate clutch, a piston for axially pressing the multi-plate clutch, an actuator for axially moving the piston, and a control unit for controlling the actuator. Upon satisfaction of a predetermined condition that indicates a high probability of the vehicle needing to be switched from the two-wheel drive mode to the four-wheel drive mode, the control unit causes the actuator to displace the piston by a predetermined amount with respect to an initial position of the piston toward the multi-plate clutch.

Abstract: A third upper MOS and a third motor relay are disposed on a front surface of a substrate. A third shunt resistor and a third lower MOS are disposed on a back surface of the substrate. The substrate has a via electrically connecting interconnects. Thus, a source electrode of the third upper MOS and a drain electrode of the third motor relay are electrically connected to a source electrode of the third lower MOS by the via.

Abstract: A differential device includes: a differential case on which a meshed portion is formed; a tubular slide member that has a meshing portion; a differential gear mechanism disposed inside the slide member; a pinion gear shaft that supports pinion gears of the differential gear mechanism; and an actuator that moves the slide member in the axial direction. The slide member has a cylindrical portion, on one side of which in the axial direction the meshing portion is formed, and a long hole that extends in the axial direction of the cylindrical portion and that opens toward the other side in the axial direction, which is the opposite side from the meshing portion. The pinion gear shaft is fitted with the long hole, and supported by the slide member. A reinforcing ring that suppresses deformation of the slide member is attached to an end portion of the cylindrical portion in which the long hole opens.

Abstract: A steering device includes a column shaft, a column jacket, a fastening mechanism including a fastening shaft having a first flat portion, a first tooth member, a second tooth member, an energizing member, and a release member including: a cylindrical portion having a second flat portion; and a release portion, wherein: the release member is configured to cause the release portion to be engaged with the second tooth member; and a projecting portion formed on at least one of the first flat portion and the second flat portion is elastically engaged with the other one of the first flat portion and the second flat portion and restrain backlash between the first flat portion and the second flat portion.

Abstract: A taper roller bearing includes: an inner ring, an outer ring, a plurality of taper rollers, and an annular cage. The cage includes a small-diameter annular portion on one axial side, a large-diameter annular portion on the other axial side, and a plurality of column portions. A radial inner surface of the column portion is provided along a second virtual taper surface that is in the vicinity of a first virtual taper surface including a center line of the plurality of taper rollers, across the entire length in the longitudinal direction of the column portion.

Abstract: In an electric power steering system, an offset correction value setting unit corrects second offset correction values in a state where 100% of current command values is distributed to a first control unit, and 0% of the current command values is distributed to a second control unit. The offset correction value setting unit corrects first offset correction values in a state where 100% of the current command values is distributed to the second control unit, and 0% of the current command values is distributed to the first control unit.

Abstract: A clutch apparatus includes a clutch hub, a clutch drum, a multi-plate clutch having inner clutch plates and outer clutch plates, a piston for pressing the multi-plate clutch, an electric motor, a moving mechanism for moving the piston in an axial direction in accordance with the amount of rotation of the electric motor, and a control unit for controlling the electric motor. When increasing a rotational force that is transmitted between the clutch hub and the clutch drum by increasing electric current that is supplied to the electric motor, the control unit moves the piston in the axial direction by temporarily supplying the electric motor with the electric current having a first current value that is greater than a second current value corresponding to a target rotational force that needs to be transmitted between the clutch hub and the clutch drum.

Abstract: A production method for a cover attached to an outer ring of a hub unit including procedures as follows. A nut is supported by a first protrusion of a first mold. By a second protrusion of a second mold, a core bar including a cylindrical section to be inserted into the outer ring is supported. A resin material is injected into a cavity formed by the first mold and the second mold to form a cover including a nut and a core bar. The cover is detached from the second mold by moving the first mold in a direction of being separated from the second mold. After this, the cover is detached from the first mold by pushing out the cover in a die matching direction with a pin disposed in the first mold.

Abstract: A gear machining method includes: roughing a workpiece while causing a cylindrical hob cutter to rotate in synchronization with a rotation of the workpiece such that a cutting allowance remains; and finishing by cutting off the cutting allowance remaining on the workpiece on which the roughing has been performed during the roughing to form a desired gear shape by feeding a skiving cutter relatively to the workpiece in the rotation axis direction of the workpiece while causing the skiving cutter to rotate in synchronization with the rotation of the workpiece.

Abstract: A method is provided that forms a solid film on a bearing component of a rolling bearing. A solution containing a fluorine compound and a lubricant having no functional group is allowed to adhere to the bearing component as a liquid film, the fluorine compound containing 3-(trimethoxysilyl) propyl methacrylate, hexafluoropropene, and methyl methacrylate as components. The solid film is formed on the at least one of the bearing components by hardening the adhering liquid film.

Abstract: A ratio of the distance by which a rack shaft moves in a first direction relative to the angle by which a pinion shaft rotates in a circumferential direction is defined as a stroke ratio. The stroke ratio is larger when the pinion meshes with one of a third rack and a fifth rack than when the pinion meshes with a first rack. The stroke ratio changes while the pinion moves on one of a second rack and a fourth rack. A clearance defined between a rack guide and a guide plug is smaller when the pinion meshes with one of the third rack and the fifth rack than when the pinion meshes with the first rack. The clearance defined between the rack guide and the guide plug changes while the pinion moves on one of the second rack and the fourth rack.

Abstract: A ball bearing includes an inner ring having an outer periphery in which an inner raceway groove is formed, an outer ring having an inner periphery in which an outer raceway groove is formed, a plurality of balls interposed between the inner raceway groove and the outer raceway groove, and an annular cage that holds the balls. The cage includes an annular portion positioned on one side in an axial direction with respect to the balls and a plurality of cage bar portions that extends from the annular portion toward the other side in the axial direction. Each cage bar portion has a guide portion, and this guide portion positions the cage by coming into contact with the outer raceway groove at one location in a non-contact area other than an area in which the corresponding ball is in contact with the outer raceway groove.

Abstract: A production method for a cover attached to an outer ring of a hub unit first prepares a first mold and a second mold which form a cavity filled with a resin material. Next, by a protrusion of the first mold, a nut is supported. Next, when viewed from an axial direction of the nut, in a state where at least a part of the gate of the second mold overlaps an inside of the nut as compared with an outer circumferential surface of the nut, the first mold and the second mold are die-matched. Then, a resin material is injected into the cavity.

Abstract: A four-wheel drive vehicle includes a dog clutch that selectively interrupts transmission of a drive force to a propeller shaft, first and second multi-plate clutches that selectively interrupt transmission of the drive force from the propeller shaft to left and right rear wheels, first and second pistons that press the first and second multi-plate clutches, and a hydraulic circuit that supplies hydraulic oil to first and second cylinder chambers. During a transition to a four-wheel drive mode, torque transmitted through the first multi-plate clutch increases the speed of rotation of the propeller shaft so as to engage the dog clutch, and the second multi-plate clutch is kept from transmitting torque to the propeller shaft.

Abstract: A steering system includes: a rack shaft movable in the axial direction; a cylindrical nut member made of metal and threadedly engaged with a spiral screw groove formed in the outer peripheral surface of the rack shaft via a plurality of balls; a pulley made of a resin and externally fitted with the nut member so as not to be rotatable relative to the nut member; a belt wound around the pulley; an electric motor that rotates the pulley and the nut member via the belt; and a retention ring, a plate spring portion of which is disposed between the outer peripheral surface of the nut member and the inner peripheral surface of the pulley in an elastically deformed state. The retention ring presses a second planar portion formed on the inner peripheral surface of the pulley radially outward using a restoring force of the plate spring portion.