| 摘要 |
PURPOSE: To improve the sealing relation between a bearing ring and a spindle so that a larger volume of compressed air can be supplied to a receptacle to purge it, by loading annular seals in a second and a third annular groove with compressed air applied radially from the side opposite to the spindle. CONSTITUTION: A compressed-air duct 30 is defined through a spatially fixed bearing ring 12 in a spindle stock 11 down to a region between two annular seals 42 and 43. When this compressed-air duct 30 is loaded with compressed air in the stationary condition of a spindle 13, these two annular seals 42 and 43 deform outward and separate from each other axially by the air pressure and are put into butt contact with the radial front of annular grooves 40 and 41 formed around the spindle 13. This seals the transition part from the spatially fixed bearing ring 12 to the rotatable spindle 13 about the external annular grooves 40 and 41. When the compressed air is shut off as a stop of the purging process, on the other, the annular seals 42 and 43 return to their original positions again by elasticity, where they no longer butt against the spindle 13. |
