| 摘要 |
PURPOSE:To enable reduction of damage to a gear by providing a bellows between an internal gear and an external pinion which constitutie a floating internally touched gear pair and by shutting off a gap between the said gears from the outside and preventing entry of an alien substance into the geared part of the gears from such a gap. CONSTITUTION:As a transmission mechanism, a transmission belt 4 is laid between a drive wheel 1 and a driven wheel 2, and e.g. an internal gear 2a formed in the inner circle of the driven wheel is floatingly geared to an external pinion 3 so as to adjust tension of the transmission belt 4 automatically. At this point, hollow disc type guide plates 5 are fixed to both sides of the driven wheel 2 with a belt 6 and a nut 7, and at the same time a bellows 8 is inserted into an axis 3a of the external pinion 3 and its boss 8a is fixed to the axis 3a, and an outter periphery 8b is movably touched to the side of a guide plate. By this, the gap between the internal gear 2 and an external pinion 3 is shuf off from the outside so as to prevent entry of an alien substance into the geared part of the gears 2 and 3 and reduce damage to a tooth. |
