| 摘要 |
PURPOSE:To confirm the non-contact state between the fixed side and the revolution side by checking the electric conductivity between the both by forming a part or all part of a bearing from resin and providing the resin electric conductivity. CONSTITUTION:A part or all part of a bearing is made of resin to provide the resin electric conductivity. In a dynamic-pressure fluid bearing, a thrust receiving part 6, bearing sleeve 5, and a thrust plate 16 are made of the self-lubricating resin such as polyacetal, nylon, tetron, polyphenylene sulfide resin, etc. containing 25% or more carbon fiber by weihgt to provide electric conductivity. Since shafts 1 and 14 and the sleeve 16 are made of SVS, etc., and Cr plating is applied to provide sliding performance, the check for electric conductivity by oscillograph in the raidal and the thrust directions is permitted. Therefore, the presence of minute metallic powder harmful to the magnitude of gap and the contact between the fixed side and the revolution side can be detected. |
