| 摘要 |
A mechanical transmission comprises first and second speed reduction gears arranged above each other and a shaft operated by the gears, the shaft supporting at a free end a pulley coaxially rotatable therewith. A first articulated coupling is axially slidable on the shaft between the gears and is provided with a lower and upper toothing. The upper toothing engages with a first flanged sleeve rotatably connected to the first reduction gear and the lower toothing is connected to a second flanged sleeve rotatably connected to the second reduction gear, and axially slidable within a seat thereof. |
