| 摘要 |
PURPOSE:To prevent grinding by fine grains in the liquid and corrosion by medicament by forming a driven shaft rotatably holding a driven gear with ceramic having high hardness and strong corrosion resistance. CONSTITUTION:The bearing hole 16 of a driven gear 6 is made slightly larger than the diameter of a driven shaft 13, thus a small gap (t) is assured between the bearing hole 16 and the outer periphery of the driven shaft 13, and the driven gear 6 is rotatably fitted to the driven shaft 13. Therefore, fine grains in the fluid infiltrated into the gas (t) during the operation are stuck to the inner periphery of the bearing hole 16, and the contact portion of the driven shaft 13 with the bearing hole 16 is ground by these fine grains, but since the driven shaft 13 is formed with ceramic having high hardness and strong corrosion resistance, it is not made slender due to grinding by fine grains in the liquid. In addition, even if medicament is mixed in the liquid, corrosion by medicament can be prevented. |
