| 摘要 |
PROBLEM TO BE SOLVED: To provide a belt type power transmission device for an internal combustion engine which has an auxiliary unit rotating at a higher speed than crank shaft and is capable of enhancing the durability by suppressing deformation of a power transmitting belt.SOLUTION: The crank shaft 2 and a water pump drive shaft 3 protrude from one surface of the engine body 1, and thereto pulleys 4 and 5 are fixed. An alternator 8 as one example of the auxiliary unit is fixed to the engine body 1, and a wheel 10 is fixed to the rotary shaft 9 of the alternator 8, and a ring-shaped idler pulley 11 is inscribing to the wheel 10. A belt 7 is set over the three pulleys 4, 5, 11. A tension roller 12 of a tensioner is inscribing with the ring-shaped idler pulley 11. Because the ring-shaped idler pulley 11 has a much greater diameter than the wheel 10, it is possible to reduce the power loss and enhance the durability by suppressing deformation of the belt 7 while the rotary shaft 9 is left rotating at a high speed. |
