ROTARY BEARING, ROTARY TABLE DEVICE AND TABLE DIAMETER DETERMINING METHOD

摘要

A rotary table device includes a hollow motor drive source, a table rotated thereby, and a rotary bearing supporting the table. The rotary bearing is provided an outer race having an inner surface to which a rolling surface is formed, an inner race having an outer peripheral surface to which a rolling surface opposing to the rolling surface of the outer race is formed, and a plurality of rolling members disposed in a rolling passage formed by the rolling surface of the outer race and the rolling surface of the inner race, and a cooling medium passage (α, β) is formed so as to be adjacent to either one of the inner race and outer race constituting a rotational driving side. According to the structure mentioned above, a rotary bearing and a rotary table device capable of achieving suitable cooling effect can be provided.