| 摘要 |
PURPOSE:To enable to take out differential output with ease, by forming gear portions having different numbers of teeth at the axially opposite ends of a planetary roller, and keeping these gear portions of the planetary roller in mesh with respective internal gears in a differential type planetary reduction gear mechanism or the like. CONSTITUTION:When an input shaft 10 is turned, a planetary roller 2 kept in rolling contact with a sun roller 1 is turned around its own axis. Here, if an internal gear 5 is fixed, the planetary roller 2 is also turned around the sun roller 1 since a gear portion 21 of the roller 2 is held in mesh with the internal gear 5. The planetary roller 2 thus turned according to the numbers of teeth of its gear portion 21 and the internal gear 5 has another gear portion 22 having a different number of teeth from that of the gear portion 21 and causes rotation of another internal gear 6 at a rate based on the difference in the number of teeth of the gear portions 21 and 22. Here, an inscribed roller 4 is turned freely. Since the high-speed section on the input side employs frictional transmission, the noise is low and the service life is long. Further, since the low-speed section employs gear transmission, slippage is not caused, so that the efficiency of power transmission is made high. |
