| 摘要 |
<p>A five speed ratio and reverse gearbox incorporates an input shaft 15, output shaft 18 and lay-shaft 23. The lay-shaft and its integral driving gears for first, second, third and fifth gear ratios are driven continuously from the input shaft through gears 26 and 27. Conventional synchronisers 38, 44 and 45 are provided to engage first, second and third driven gears 33, 34 and 35 respectively with the output shaft 18 to select any of these ratios. Fourth gear ratio is a direct drive from input shaft to output shaft through an over-running clutch 49 and synchroniser 46. Fifth gear ratio, incorporating lay-shaft gear 31 and output shaft gear 36, is established by engagement of wet clutch 51. Pump 62 supplies oil under pressure to clutch 51 but only when valve 63 is closed which in turn is only when fourth gear ratio has been selected.</p> |
