Abstract: An object of the present invention is to remove adverse effects on an in-wheel motor driving apparatus due to the existence of moisture in the apparatus. There is provided an in-wheel motor driving apparatus in which a driving apparatus for generating driving force of a wheel having a wheel hub bearing section is provided in the wheel, the in-wheel motor driving apparatus, wherein a portion of the driving apparatus, except the wheel hub bearing section, is housed in a case having a sealed structure and thereby the inside of the driving apparatus is blocked from outside air, and air in the case is replaced with inert gas as required. As a result, dew condensation is prevented in the case, and adverse effects due to the existence of moisture in the case are removed.

Abstract: To reduce the weight of the drive system as a whole with a central focus placed on an inverter, particularly, the length of a wiring and a tubing around the inverter and also to reduce the weight of an electric vehicle through an efficient cooling of the inverter, a single inverter (5) used to supply an alternating current power to all in-wheel motor devices (4) is positioned at a bilateral position positioned between the left and right in-wheel motor devices (4). A radiator (7) for cooling the inverter (5) is positioned forwardly of the inverter (5). The inverter (5) is disposed above a battery (6) or the inverter (5) and the battery (6) are disposed forwardly and rearwardly relative to each other.

Abstract: A sensor equipped axle unit having an in-wheel type motor built therein, in which a hub bearing assembly (A), an electric motor (B), a reduction gear unit (C) and a brake assembly (D) are arranged coaxially on a center axis of a vehicle drive wheel. Sensors (80, 81 and 82) are provided for measuring forces Fx, Fy and Fz acting at a point of contact of the vehicle drive wheel (70) and a road surface in three axis directions perpendicular to each other, respectively, from the status of at least one of the hub bearing assembly (A), the electric motor (B), the reduction gear unit (C) and the brake assembly (D). Results of such measurement are utilized for a suspension control, an ABS control and any other control.

Abstract: The sectional shape of a rolling surface of at least one of bearing component parts has the following relation between the order n (n being an arbitrarily chosen natural number) and the amplitude r of waviness relative to the circularity of the sectional shape. The order n and the amplitude r are logarithmically transformed to define X=Log(n) from the order n and Y=Log (rn) from the amplitude r of n-order. When a regression line Y=aX+b is determined, the ratio ?/? of the deviation ? at each X from the regression line of Y to the standard deviation ? is chosen to be smaller than 4.

Abstract: A rolling bearing assembly has an inner race, an outer race and a plurality of rolling elements interposed between respective raceway surfaces of the inner and outer races. A stationary raceway member, which is one of the inner and outer races that are a raceway member and which is non-rotatable, is provided with a stepped face continued with the corresponding raceway surface and located in a direction away from the rolling elements, and is also provided with a gap defining piece having a tip held in face-to-face relation to the stepped face with a gap intervening between it and the stepped face and defining a flow path between a peripheral wall thereof and the stationary raceway member; there being provided a grease reservoir communicated with the flow path.

Abstract: An evaluation method for a rolling bearing part capable of easily and properly detecting deformation of the rolling contact surface of the rolling bearing part formed of raceway rings or rolling element of a rolling bearing. First, the order and amplitude of waviness on the rolling contact surface of the rolling bearing part are obtained by harmonic analysis for the circularity of the rolling contact surface. The order and amplitude of waviness so obtained are logarithmically converted, and the regression line showing a relation between the logarithmically converted order of waviness and the amplitude of waviness is obtained. Based on the deviation from the regression line, the deformation of the rolling contact surface is evaluated.

Abstract: A lubricating device for a rolling bearing includes a lubricating oil introduction member (7) that has a discharge opening (8) opened to a circumferential groove (6) provided in an end face of an inner race (2) of a bearing (1). A slope section (2b) is provided on an outer peripheral surface of the inner race (2) and guides the lubricating oil in the groove (6) to a raceway surface (2a) of the inner race (2) by centrifugal force and surface tension acting on the lubricating oil. The introduction member (7) is provided with a flange-like section (10) that overlays the slope section (2b) with a minute gap ? between the flange-like section (10) and the slope section (2b) and that controls the flow amount of the lubricating oil flowing through the gap ? to the raceway surface (2a).

Abstract: A method that utilizes signals from an accelerometer in resonant frequency bands or high frequency bands to, in a cost-effective manner, measure wear particle penetration of lubricant and lubricant degradation, both of which greatly affect prediction of residual service life; and, using as a basis these measurements of wear particle penetration and lubricant degradation, enables accurate estimation of residual service life for rolling bearings in the early stages.

Abstract: An evaluation method for a rolling bearing part capable of easily and properly detecting deformation of the rolling contact surface of the rolling bearing part formed of raceway rings (1, 2) or rolling element (3) of a rolling bearing. First, the order and amplitude of waviness on the rolling contact surface of the rolling bearing part are obtained by harmonic analysis for the circularity of the rolling contact surface. The order and amplitude of waviness so obtained are logarithmically converted, and the regression line showing a relation between the logarithmically converted order of waviness and the amplitude of waviness is obtained. Based on the deviation from the regression line, the deformation of the rolling contact surface is evaluated.

Abstract: A sensor equipped axle unit having an in-wheel type motor built therein, in which a hub bearing assembly (A), an electric motor (B), a reduction gear unit (C) and a brake assembly (D) are arranged coaxially on a center axis of a vehicle drive wheel. Sensors (80, 81 and 82) are provided for measuring forces Fx, Fy and Fz acting at a point of contact of the vehicle drive wheel (70) and a road surface in three axis directions perpendicular to each other, respectively, from the status of at least one of the hub bearing assembly (A), the electric motor (B), the reduction gear unit (C) and the brake assembly (D). Results of such measurement are utilized for a suspension control, an ABS control and any other control.

Abstract: The sectional shape of a rolling surface of at least one of bearing component parts has the following relation between the order n (n being an arbitrarily chosen natural number) and the amplitude r of waviness relative to the circularity of the sectional shape. The order n and the amplitude r are logarithmically transformed to define X=Log(n) from the order n and Y=Log (rn) from the amplitude r of n-order. When a regression line Y=aX+b is determined, the ratio ?/? of the deviation ? at each X from the regression line of Y to the standard deviation ? is chosen to be smaller than 4.

Abstract: A lubricating device for a rolling bearing includes a lubricating oil introduction member (7) that has a discharge opening (8) opened to a circumferential groove (6) provided in an end face of an inner race (2) of a bearing (1). A slope section (2b) is provided on an outer peripheral surface of the inner race (2) and guides the lubricating oil in the groove (6) to a raceway surface (2a) of the inner race (2) by centrifugal force and surface tension acting on the lubricating oil. The introduction member (7) is provided with a flange-like section (10) that overlays the slope section (2b) with a minute gap ? between the flange-like section (10) and the slope section (2b) and that controls the flow amount of the lubricating oil flowing through the gap ? to the raceway surface (2a).

Abstract: A rolling bearing assembly includes an inner race (1), an outer race (2) and a plurality of rolling elements (3) interposed between respective raceway surfaces (1, 2a) of the inner and outer races (1, 2). A stationary raceway member (2), which is one of the inner and outer races (1, 2) that are a raceway member and which is non-rotatable, is provided with a stepped face (2b) continued with the corresponding raceway surface (2a) and located in a direction away from the rolling elements (3). A gap defining piece (7) is provided, which has a tip held in face-to-face relation to the stepped face (2b) with a gap intervening between it and the stepped face (2b) and which defines a flow path (14) between a peripheral wall thereof and the stationary raceway member (2). A grease reservoir (9) is also provided in communication with the flow path (9).

Abstract: Degradation of the lubricant due to contamination of the lubricant with wear particles or moisture, which greatly affects the service life of rolling bearings, can be detected in a cost-effective manner through the use of a resonance frequency band signal or high-frequency signal of an accelerometer, and the service life of a rolling bearing can be estimated with high precision at an early stage on the basis of the detected state of the wear particles and lubricant.

Abstract: Rolling bearing is disclosed in which the surfaces of the rolling elements or raceway surfaces is randomly formed with an innumerable number of independent minute recessed depressions 11, the regions other than the depressions being smooth surfaces, and when an equivalent circle diameter of not more than ?3 ?m excluded, the average area of the depressions is from not less than 10 ?m2 to not more than 70 ?m2, the maximum area being 1200 ?m2.

Abstract: The squareness of the both end surfaces of the flange portion with respect to the outer circumference of the shaft portion of the shaft member is set to 0.001 mm or less respectively, and the flatness of both end surfaces of the flange portion is set to 0.001 mm or less respectively. The squareness of the end surface of the bearing member with respect to the inner circumference of the bearing member is set to 0.002 mm or less, and the flatness thereof is set to 0.0015 mm or less. The flatness of the inner surface of the bottom portion of the housing is set to 0.002 mm or less.

Abstract: An invention that utilizes signals from an accelerometer in resonant frequency bands or high frequency bands to, in a cost-effective manner, measure wear particle penetration of lubricant and lubricant degradation, both of which greatly affect prediction of residual service life; and, using as a basis these measurements of wear particle penetration and lubricant degradation, enables accurate estimation of residual service life for rolling bearings in the early stages.

Abstract: The squareness of the both end surfaces of the flange portion with respect to the outer circumference of the shaft portion of the shaft member is set to 0.001 mm or less respectively, and the flatness of both end surfaces of the flange portion is set to 0.001 mm or less respectively. The squareness of the end surface of the bearing member with respect to the inner circumference of the bearing member is set to 0.002 mm or less, and the flatness thereof is set to 0.0015 mm or less. The flatness of the inner surface of the bottom portion of the housing is set to 0.002 mm or less.

Abstract: The squareness of the both end surfaces of the flange portion with respect to the outer circumference of the shaft portion of the shaft member is set to 0.001 mm or less respectively, and the flatness of both end surfaces of the flange portion is set to 0.001 mm or less respectively. The squareness of the end surface of the bearing member with respect to the inner circumference of the bearing member is set to 0.002 mm or less, and the flatness thereof is set to 0.0015 mm or less. The flatness of the inner surface of the bottom portion of the housing is set to 0.002 mm or less.

Abstract: Rolling bearings are proposed in which acoustic deterioration is suppressed which maintaining low dust, low torque and long life. Also, a grease for rolling bearings is proposed which is less likely to scatter under centrifugal force at high speed rotation, whereby preventing malfunction and noise of electronic information devices. A lubricating oil film of an ester-series oil having a dynamic viscosity at 40° C. of 35 mm2/s or over is formed on the friction surface of a rolling bearing. There is also provided a high-speed rolling bearing in which a lubricating grease having its worked penetration (JIS K2220) adjusted to 175-250 is retained therein. The grease is preferably prepared by adding a thickening agent containing 50 wt % or more of an aliphatic lithium salt 12-24 in carbon number to a base oil comprising 30 wt % or more of an ester oil having a dynamic viscosity at 40° C. of 10 mm2/s or over, and having its worked penetration (JIS K2220) adjusted to 175-250.