Patent ID: 7305900

Claim:
A twin-clutch transmission comprising: a first input shaft and a second input shaft connected, through a first clutch and a second clutch, respectively, to an input element, and disposed on the same axis; an auxiliary speed-change shaft disposed parallel to the first and second input shafts; and a plurality of gear pairs provided between the first and second input shafts and the auxiliary speed-change shaft; wherein one of the first and second clutches is selectively engaged while the other is disengaged, and one of the first and second input shafts that is coupled to the corresponding one of the first and second clutches is interlocked with the auxiliary speed-change shaft through engagement of a required one of the plurality of gear pairs, thereby achieving a required speed-change ratio; wherein an input path from the input element to the first clutch is different from that to the second clutch, and primary ratios of the input paths are set to values, respectively, different from each other, wherein a sixth gear pair is operatively connected to the first input shaft, and wherein a dog clutch is operatively positioned between the first and second input shafts for selectively causing the first and second input shafts to be integrally rotated for transmitting rotation from said second clutch to the second input shaft and to the first input shaft and to the sixth gear pair for a sixth speed.