Abstract: A rotation transmission device having a high torque measurement resolution is provided.

Abstract: A friction roller-type reduction gear includes a sun roller concentric with an input shaft, a ring roller having a stationary ring roller element and a moveable ring roller element, intermediate rollers in rolling contact with an outer peripheral surface of the sun roller and an inner peripheral surface of the ring roller, a coupling part coupling the ring roller and the output shaft, and a loading cam mechanism having a cam ring for changing contact surface pressure of each rolling contact surface. The outer surface of the sun roller is a concave curved surface of which a shape of an outer edge in an axial cross-section is a single circular arc-shaped concave curve, and an outer surface of the intermediate roller is a convex curved surface of which a shape of an outer edge in an axial cross-section is a single circular arc-shaped convex curve.

Abstract: A friction roller-type reduction gear includes a sun roller arranged concentrically with an input shaft, a ring roller having a stationary ring roller element and a moveable ring roller element, a plurality of intermediate rollers configured to be in rolling contact with an outer peripheral surface of the sun roller and an inner peripheral surface of the ring roller, a coupling part configured to couple the ring roller and the output shaft, and a loading cam mechanism having a cam ring and configured to change a contact surface pressure of each rolling contact surface. The outer peripheral surface of the sun roller is a concave curved surface of which a shape of an outer edge in an axial cross-section is a single circular arc-shaped concave curve, and an outer peripheral surface of the intermediate roller is a convex curved surface of which a shape of an outer edge in an axial cross-section is a single circular arc-shaped convex curve.

Abstract: A vehicle wheel supporting rolling bearing unit includes a bearing part having a stationary side bearing ring member which is supported and fixed to a suspension device and non-rotatable in a use state and a rotation side bearing ring member which is coupled and fixed to a vehicle wheel and rotate together with the vehicle wheel, an electric generator which generates electric power to be supplied to a sensor provided on the vehicle wheel, a battery which stores the electric power generated by the electric generator, and a wireless communication device which wirelessly communicates an output signal of the sensor with an electronic equipment arranged on a vehicle body side. The stator is supported and fixed to the stationary side bearing ring member, and the rotor, the battery and the wireless communication device are supported and fixed to the rotation side bearing ring member.

Abstract: A rotation transmission device having a high torque measurement resolution is provided.

Abstract: In order to implement a structure capable of improving the resolution of torque measurement while preventing the plastic deformation of a torsion bar (15), an input-side stopper (61) having an uneven shape (gear shape) in the circumferential direction is provided in a portion of an input-side rotating body (55) that includes an input shaft (13) and an input gear (7), and an output-side stopper (63) having an uneven shape (gear shape) in the circumferential direction is provided in a portion of an output-side rotating body (56) that includes an output shaft (14) and an output gear (8). The input-side stopper (61) and the output-side stopper (63) are combined so as to be engaged to be able to transmit torque only when the torsional angle within the elastic range of the torsion bar (15) reaches a predetermined amount.

Abstract: A rotation transmission device having a high torque measurement resolution is provided.

Abstract: In order to implement a structure capable of improving the resolution of torque measurement while preventing the plastic deformation of a torsion bar (15), an input-side stopper (61) having an uneven shape (gear shape) in the circumferential direction is provided in a portion of an input-side rotating body (55) that includes an input shaft (13) and an input gear (7), and an output-side stopper (63) having an uneven shape (gear shape) in the circumferential direction is provided in a portion of an output-side rotating body (56) that includes an output shaft (14) and an output gear (8). The input-side stopper (61) and the output-side stopper (63) are combined so as to be engaged to be able to transmit torque only when the torsional angle within the elastic range of the torsion bar (15) reaches a predetermined amount.

Abstract: To realize a manufacturing method for a wheel-supporting rolling bearing unit that can establish sufficient parallelism between a rotating side installation surface 14 for fastening to and supporting a disk of a disk brake and a stationary side installation surface 15 for fastening a caliper or support, in the present invention, while rotating a hub 2 comprising the rotating side installation surface 14 with respect to an outer race comprising the stationary side installation surface, a finishing process such as turning is performed on the rotating side installation surface 14 or both side surfaces in the axial direction of the disk which is fastened and supported to and by the rotating side installation surface 14, with the stationary side installation surface 15 as a reference surface.

Abstract: A hub unit for wheel is described, with an outer ring having two bearing tracks on its inner circumferential surface, and a hub having a wheel mount flange on the outer end side and an end portion on the axially vehicle center side. The hub has a first bearing track corresponding to the axially vehicle outer end side bearing track of the outer ring, and an inner ring element fitted on the end portion side of the hub. The inner ring element has on its outer circumference a second bearing track opposed to the axially vehicle center side bearing track of the outer ring, and is fixed on the end portion by plastically deforming the end portion of the hub radially outwardly. Rolling members are provided between the two bearing tracks of the outer ring and the first and second bearing tracks.

Abstract: To realize a manufacturing method for a wheel-supporting rolling bearing unit that can establish sufficient parallelism between a rotating side installation surface 14 for fastening to and supporting a disk of a disk brake and a stationary side installation surface 15 for fastening a caliper or support, in the present invention, while rotating a hub 2 comprising the rotating side installation surface 14 with respect to an outer race comprising the stationary side installation surface, a finishing process such as turning is performed on the rotating side installation surface 14 or both side surfaces in the axial direction of the disk which is fastened and supported to and by the rotating side installation surface 14, with the stationary side installation surface 15 as a reference surface.

Abstract: A hub unit for wheel is provided with an outer ring having two bearing tracks on its inner circumferential surface, a hub having a wheel mount flange on the outer end side and an end portion on the axially vehicle center side, the hub having, as a separate part or integrally on its outer circumference, a first bearing track corresponding to the axially vehicle outer end side bearing track of the outer ring, an inner ring element fitted on the end portion side of the hub, the inner ring element having on its outer circumference a second bearing track opposed to the axially vehicle center side bearing track of the outer ring and being fixed on the end portion by plastically deforming the end portion of the hub radially outwardly, and rolling members provided between the two bearing tracks of the outer ring and the first and second bearing tracks.

Abstract: A construction is adopted in which an annular spacer 27 is held between first and second inner races 2a, 2b. An internal clearance in a double-row bearing unit is measured in a middle step of assembling work of a wheel supporting bearing assembly, and in the event that a resultant measured value does not become a proper value, an axial dimension of the spacer 27 is adjusted, so that the internal clearance becomes the proper value. Thereafter, the assembling work is made to continue until the assembling work is completed. A problem which is to be solved by the invention is solved in the way described above.

Abstract: It is intended that the rotation resistance is decreased while the durability and seal performance are kept in the rolling bearing unit with seal ring. The most thin wall-thickness portion 30 is provided in the vicinity of the base end of the seal lip 22a projecting laterally in sliding contact with the mating surface. The most thick wall thickness portion 31 is provided adjacent to the most thin wall thickness portion 30 on the tip end side. The thickness is gradually decreased from the most thick wall thickness portion 31 to the tip end. Further, the ratios of thickness in the respective portions 22a are properly controlled.

Abstract: It is intended that the rotation resistance is decreased while the durability and seal performance are kept in the rolling bearing unit with seal ring. The most thin wall-thickness portion 30 is provided in the vicinity of the base end of the seal lip 22a projecting laterally in sliding contact with the mating surface. The most thick wall thickness portion 31 is provided adjacent to the most thin wall thickness portion 30 on the tip end side. The thickness is gradually decreased from the most thick wall thickness portion 31 to the tip end. Further, the ratios of thickness in the respective portions 22a are properly controlled.

Abstract: An amount of undulation by which the inner surface 11 of a large-diameter-side flange portion 8 formed in an inner ring 5 is undulated is defined as an axial deflection &dgr;. And, the composite roughness of a contact portion between the inner surface 11 and the head portion 10 of a tapered roller 6 is expressed as &sgr;. A tapered roller bearing 1 is structured in such a manner that &dgr;≦8 &mgr;m and &sgr;≦0.22 &mgr;mRMS, or, &dgr;≦12 &mgr;m and &sgr;≦0.18 &mgr;, or, &dgr;≦16 &mgr;m and &sgr;≦0.13 &mgr;mRMS can be satisfied.

Abstract: An amount of undulation by which the inner surface 11 of a large-diameter-side flange portion 8 formed in an inner ring 5 is undulated is defined as an axial deflection 8. And, the composite roughness of a contact portion between the inner surface 11 and the head portion 10 of a tapered roller 6 is expressed as &sgr;. A tapered roller bearing 1 is structured in such a manner that &dgr;≦8 &mgr;m and &sgr;≦0.22 &mgr;mRMS, or, &dgr;≦12 &mgr;m and &sgr;≦0.18 &mgr;, or, &dgr;≦16 &mgr;m and &sgr;≦0.13 &mgr;mRMS can be satisfied.

Abstract: In the roller bearing, between an outer ring (1) and an inner ring (2), there are interposed a plurality of tapered rollers (3) in a freely rollable manner. A flange portion (4) is formed in the side portion of the inner ring (2). The undercut allowance ratios of a contact ellipse formed due to mutual contact between the flange portion (4) and the end face of the roller (3) is set in the range of −0.6≦(h−b−c)/b≦2, where a grinding undercut dimension on the flange portion (4) is expressed as c, a contact point height between the flange portion (4) and the end face of the roller (3) is expressed as h, and the minor radius of a contact ellipse formed due to contact between the flange portion (4) and the end face of the roller (3) is expressed as b.

Abstract: An inner ring of a tapered roller bearing is provided with an groove-like recess formed between an outer race surface and a large rib surface. A Chamfer is provided between a large-diameter-side end surface and a rolling surface in each tapered roller. (1) The height from the outer race surface of the inner ring to a contact position where the inner ring large rib surface contacts with the large-diameter-side end surface of each roller is set to be 6 to 9.5% of the diameter of the roller large-diameter-side end surface. (2) The chamfer of the large-diameter-side end surface of each roller is set to be 30 to 60% of the contact position height. In addition, (3) the size of the recess in the large rib surface side of the inner ring is set to be not larger than 75% of the chamfer of the large-diameter-side end surface of each roller.

Abstract: A roller bearing comprising an outer ring having an outer ring raceway, an inner ring having an inner ring raceway, the inner peripheral surface at the end portion of the outer ring and/or the outer peripheral surface at the end portion of the inner ring formed with a flange portion, and a plurality of rollers having a rolling surface in contact with the outer and inner ring raceways, a sliding contact face in sliding contact with the inner face of the flange portion, and a chamfered portion provided between the sliding contact face and the rolling face, the sliding contact face smoothly connected to the chamfered portion in a curved surface the radius of curvature of which is at least 0.08 mm, and provided that the center line average height roughness of the sliding contact surface is .delta..sub.1 while the center line average height roughness of the inner face in contact with the sliding surface is .delta..sub.2, the composite roughness represented by the formula (.delta..sub.1.sup.2 +.delta..sub.2.sup.2).