BEARING FOR HIGH SPEED MAIN SHAFT OF MACHINE TOOL

PURPOSE:To effectively cool a bearing inner lace by providing a lead path on a collar arranged between two bearings and providing a nozzle port toward the contact position of adjacent bearing inner lace and a ball from the inner side closed end thereof. CONSTITUTION:A passage 62 formed on a bottomed hole closed by a tip part 56a is provided on a 1st bush 56, a nozzle port 64 is formed toward the tip at the side part, connected to a connection pass. 67 and an oil air feeding pass. 68 together with a 2nd bush formed at specified interval and not shown in a figure and one part lubricates the right bearing and the other the left bearing 17. Radial lead passages are open on the outer periphery at specified intervals for the 1st through hole of the tip part 56a and 2nd through hole not shown in a figure on an outer collar 19, having a nozzle port opening to the side part from the inner peripheral end, an outer peripheral groove is connected to a cooling air feeding passage 69, and one part cools the light bearing and the other the left bearing 17. A cooling gas and an oil air are fed to the outer collar 31 of a bearing 26 through feeding passages 76, 77 formed on the inner lace 33 of a bearing 32 and fed to the bearings 26, 32 through a passage 73 and the lead passage not shown in a figure and the nozzle port.