| 摘要 |
PURPOSE:To reduce weight of a change drum and improve strength of the drum by reducing three change drum grooves to two grooves and disposing the first and second-speed gears on which load is put near bearings at the shaft ends. CONSTITUTION:A guide pin 14 of a fork 7 for 5-speed top shift and a guide pin 13 of a fork 8 for 2 and 3-speed shift are fitted in a common cam groove 17 on a change drum 10, separated by 180 deg.. Therefore, two cam grooves are provided on the change drum 10, which results in a decrease in weight of the change drum 10. A fixed 2-speed gear 2 and a fixed 1-speed gear L are disposed near bearings 19, 20 at both ends of an input shaft 15, and a reversing 5-speed gear 5, sliding solid 3 and 4-speed gears 3, 4, an idling top gear T are interposed in the order from the fixed 2-speed gear 2 between those gears 2, L. An idling 2-speed gear 2' and an idling 1-speed gear L' are disposed near bearings 27, 28 at both ends of an output shaft 16, and a sliding 5-speed gear 5', idling 3 and 4-speed gears 3', 4' and a sliding top gear T' are interposed between those gears 2', L'. Clutches 23, 24, 31-34 are disposed on both sides of each sliding gear. |
