A reversing gear ( 13 d ) is disposed between a fifth fixed gear ( 13 a ) having a smallest outer diameter among respective gears provided in a first main shaft ( 4 ) and a second main shaft ( 5 ) and a sixth idling gear ( 13 b ) having a smallest outer diameter among respective gears provided in a first sub-shaft ( 6 ) to always mesh with the respective gears. A first synchronizing sleeve ( 21 ) is disposed to overlap a bearing ( 8 a ) of a third sub-shaft ( 8 ) in the axial direction of the second main shaft ( 5 ). A second synchronizing sleeve ( 22 ), a third synchronizing sleeve ( 23 ), and a fourth synchronizing sleeve ( 24 ) are disposed to overlap a bearing ( 8 b ) of the third sub-shaft ( 8 ) in the axial direction of the second main shaft ( 5 ).
1. A transmission comprising: a main input shaft to which a driving force from an internal combustion engine is input; a first main shaft to which the driving force of the main input shaft is selectively transmitted via a first clutch; a second main shaft arranged coaxially with the first main shaft, the driving force of the main input shaft being selectively transmitted to the second main shaft via a second clutch; a first sub-shaft, a second sub-shaft, and a third sub-shaft arranged in parallel to the first main shaft and the second main shaft; gear groups respectively provided in the first main shaft and the second main shaft; a gear group provided in the first sub-shaft; and a first fixed gear provided in the second sub-shaft and configured to output the driving force,
the transmission comprising a reversing gear fixedly provided in the third sub-shaft;
a first idling gear relatively rotatably supported by the second sub-shaft and configured to transmit the driving force of the first main shaft;
a second idling gear relatively rotatably supported by the second sub-shaft and configured to transmit the driving force of the second main shaft; and
a first synchronization mechanism provided in the second sub-shaft and configured to selectively transmit the driving force of the first idling gear or the driving force of the second idling gear to the second sub-shaft, wherein
the reversing gear is arranged between a gear having a smallest outer diameter in the gear groups provided in the first main shaft and the second main shaft and a gear having a smallest outer diameter in the gear group provided in the first sub-shaft to mesh with the respective gears,
both ends of the third sub-shaft are rotatably supported by bearings, and
one bearing of the third sub-shaft is disposed to overlap the first synchronization mechanism in an axial direction of the second main shaft.
2. The transmission according to claim 1 comprising:
a second synchronization mechanism configured to connect a third idling gear and the second main shaft, the third idling gear being relatively rotatably supported by the second main shaft and configured to transmit the driving force to the first sub-shaft and the second sub-shaft;
a third synchronization mechanism configured to connect a fourth idling gear and the first sub-shaft, the fourth idling gear being relatively rotatably supported by the first sub-shaft; and
a fourth synchronization mechanism configured to connect a fifth idling gear and the second sub-shaft, the fifth idling gear being relatively rotatably supported by the second sub-shaft, wherein
the other bearing of the third sub-shaft is disposed to overlap the second synchronization mechanism, the third synchronization mechanism, and the fourth synchronization mechanism in the axial direction of the second main shaft.
3. A transmission comprising: a main input shaft to which a driving force from an internal combustion engine is input; a first main shaft to which the driving force of the main input shaft is selectively transmitted via a first clutch; a second main shaft arranged coaxially with the first main shaft, the driving force of the main input shaft being selectively transmitted to the second main shaft via a second clutch; a first sub-shaft, a second sub-shaft, and a third sub-shaft arranged in parallel to the first main shaft and the second main shaft; gear groups respectively provided in the first main shaft and the second main shaft; a gear group provided in the first sub-shaft; and a first fixed gear provided in the second sub-shaft and configured to output the driving force,
the transmission comprising a reversing gear fixedly provided in the third sub-shaft;
a second synchronization mechanism configured to connect a third idling gear and the second main shaft, the third idling gear being relatively rotatably supported by the second main shaft and configured to transmit the driving force to the first sub-shaft and the second sub-shaft;
a third synchronization mechanism configured to connect a fourth idling gear and the first sub-shaft, the fourth idling gear being relatively rotatably supported by the first sub-shaft; and
a fourth synchronization mechanism configured to connect a fifth idling gear and the second sub-shaft, the fifth idling gear being relatively rotatably supported by the second sub-shaft, wherein
the reversing gear is arranged between a gear having a smallest outer diameter in the gear groups provided in the first main shaft and the second main shaft and a gear having a smallest outer diameter in the gear group provided in the first sub-shaft to mesh with the respective gears,
both ends of the third sub-shaft are rotatably supported by bearings, and
the other bearing of the third sub-shaft opposed to one bearing of the third sub-shaft is disposed to overlap the second synchronization mechanism, the third synchronization mechanism, and the fourth synchronization mechanism in the axial direction of the second main shaft.