PURPOSE: To cool a main spindle device effectively and evenly, by a method wherein a working liquid is streamed to a vapor tube, a liquid tube and a connecting tube, and a calorific value of a bearing rest is transmitted to a radiator from a hollow chamber.
CONSTITUTION: Calorific values of bearings 3-31, which received heat by bearing rests 4-41, are taken away as evaporation latent heat when a working liquid such as Flon in hollow chambers 7-71 is made to evaporate by heating the working liquid. Vapor such as the evaporated Flon is moved to a radiator 8 through a branch tube and a confluent tube of a vapor tube 10 having flexible parts and cooled by a cooling fan 9. The condensed working liquid is returned to the hollow chambers 7-71 of the bearing rests 4-41 through liquid tubes 12-121 having flexible parts. The liquid tubes 12-121 are connected through a connecting tube 13 having a flexible part with each other.
KATAOKA KENJI
YAMAKAGE HISAAKI