Patent ID: 8714827
Filing Date: 2014-05-06
Classification: F16C

Abstract:
1. A bearing assembly for a transmission that is arranged in the transmission for transmitting a rotation of an input shaft to an output shaft, comprising a plurality of balls interposed between first and second raceways defined respectively in first and second raceway rings, a retainer for retaining the balls, and a sealing member for sealing a bearing space delimited between the first and second raceway rings with a grease filled in the bearing space; wherein the retainer is formed with a plurality of pockets for retaining the respective balls, each of the pockets being defined by semicircular bulged portions opposed to each other and has an inner face formed with a recessed portion extending from a retainer inner diametric side to a retainer outer diametric side; wherein the sealing member is in the form of a contact seal including first and second end portions opposite to each other, the first end portion of the sealing member being fixed to one of the first and second raceway rings whereas the second end portion has a sealing lip region that is adapted to contact the other of the first and second raceway rings before start of running of the bearing assembly, a material for at least a tip portion of the sealing lip region being a frictionally wearable material which wears, when the bearing assembly is used in a rotating condition, to form a non-contact or a contact of a contact pressure substantially equal to zero to thereby form a labyrinth gap between the tip portion of the sealing region and the other of the first and second raceway rings having a size that allows a lubricant oil to pass through the gap and prevents particulate matters from passing the gap, and wherein the grease contains at least a base oil and a thickening agent, the base oil being a mineral oil alone or a mixed oil of mineral oil and poly-a-olefin oil and has a base oil kinetic viscosity at 40° C., which is not higher than 100 mm2/s.