Compound bearing apparatus

A compound bearing apparatus including a stepped shaft having a larger diameter shaft portion and a reduced diameter shaft portion, an inner ring fit slidably around the reduced diameter shaft portion of the stepped shaft, and a cylindrical outer ring member surrounding the shaft, a plurality of balls of the first row interposed between the first inner raceway formed on the outer periphery of the inner ring and the first outer raceway formed on the inner periphery of the outer ring member, and a plurality of balls of the second row interposed between the second inner raceway formed directly on the outer periphery of the larger diameter shaft portion and the second outer raceway formed on the inner periphery of the outer ring member, the bearing apparatus being characterized in that:

• the outer ring member includes upper and lower portions on the inner periphery of which is provided with the first and the second outer raceways respectively and a central portion therebetween,
• a squeeze ring of the same material as that used in forming the outer ring member or of any other material of substantially the same factor of linear thermal expansion as that of the outer ring member is press fit around the outer periphery of the central portion of the outer ring member to elastically deform the outer ring member inwardly to form an inwardly protruding squeezed portion,
• wherein the inner ring is secured to the shaft with applying an appropriate pre-load thereon.