(1)   the main function of the retainer as follows:
a .separation of each rolling element, so that the minimum of friction and heat in the work;
b,  maintain equal distance between the rolling element, so that the load evenly distributed;
c, separable bearings and the inner and outer rings each other swing bearing rolling element will not fall out;
d, to guide the rolling element bearing non-bearing area.
(2) Rolling maintain the frame can be subdivided into ram and entity type:
a, stamping cage: the commonly used steel plate, and sometimes copper. This cage relative to the metal entity advantage is lighter. Stamping frame occupy the gap between the bearing inner ring, lubricating easy access to the bearing and to stay in the cage. According to the principle of code, stamping Cage in it as a standard structure has been to write code.
b, solid cage: made ??of metal, phenol resin, fabric and plastic. Bearing code specified in these materials.
Metal entities to maintain the frame for the strength of the cage to the requirements of high temperature in the workplace.
Required rib guide, you can also use a solid cage. The rib-guided high-speed bearing cage made ??of light materials, such as light metal or phenol resin,

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