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A transmission for a working vehicle for transmitting drive power from an engine to a driving axle that includes: a flywheel including a flywheel body operatively connected with the engine and a flywheel housing for accommodating the flywheel body; a main-speed-change unit including a main-input sha

A transmission for a working vehicle for transmitting drive power from an engine to a driving axle that includes: a flywheel including a flywheel body operatively connected with the engine and a flywheel housing for accommodating the flywheel body; a main-speed-change unit including a main-input shaft operatively connected with the engine via the flywheel body and a main-output shaft for outputting drive power to be transmitted to the driving axle; and a sub-speed-change unit including a sub-input shaft and a sub-output shaft, and disposed with a distance from the main-speed-change unit. The engine, the flywheel and the main-speed-change unit are integrally connected with each other so as to vibrate freely relative to a vehicle frame, and the main-output shaft of the main-speed-change unit is operatively coupled with the sub-input shaft of the sub-speed-change unit via a vibration-absorbing shaft coupling.

대표청구항 ▼

1. A transmission for a working vehicle for transmitting drive power from an engine to a driving axle comprising:a flywheel including a flywheel body operatively connected with the engine and a flywheel housing for accommodating said flywheel body; a main-speed-change unit including a main-input sha

1. A transmission for a working vehicle for transmitting drive power from an engine to a driving axle comprising:a flywheel including a flywheel body operatively connected with the engine and a flywheel housing for accommodating said flywheel body; a main-speed-change unit including a main-input shaft operatively connected with the engine via the flywheel body and a main-output shaft for outputting drive power to be transmitted to the driving axle; and a sub-speed-change unit including a sub-input shaft and a sub-output shaft wherein said sub-speed-change unit is disposed at a distance from the main-speed-change unit closer to one end of the working vehicle than to said main-speed-change unit; wherein the engine, the flywheel and the main-speed-change unit are integrally connected with each other so as to vibrate freely relative to a vehicle frame; and the main-output shaft of the main-speed-change unit is operatively coupled with the sub-input shaft of the sub-speed-change unit via a shaft coupling. 2. A transmission for a working vehicle according to claim 1, further comprising a damper interposed between the flywheel body and the main-input shaft.3. A transmission for a working vehicle according to claim 1, wherein the main-input shaft and the main-output shaft of the main-speed-change unit are aligned parallel to each other in a vehicles vertical direction and offset to each other in a vehicle's lateral direction.4. A transmission for a working vehicle according to claim 1, wherein the main-speed-change nit includes an output adjusting member for adjusting the speed change ratio of the main-output shaft with respect to the main-input shaft, and the output adjusting member is operated by means of electric signals.5. A transmission for a working vehicle according to claim 1, wherein:the flywheel housing includes a body portion having an accommodation space and opposite open ends, and a partition wall for dividing said accommodation space into a first chamber for accommodating the flywheel body and a second chamber for accommodating the main-speed-change unit; and the flywheel body has a portion facing said partition wall, on which an airflow fan is provided. 6. A transmission for a working vehicle according to claim 1, wherein said shaft coupling is vibration-absorbing.7. A transmission for a working vehicle for transmitting drive power from an engine to a driving axle via a flywheel, an HST and a sub-speed-change unit, which are aligned in a power transmission direction, wherein:the flywheel includes a flywheel body operatively connected with the engine and a flywheel housing for accommodating said flywheel body; the HST includes a hydraulic pump unit having a pump shaft serving as a main-input shaft operatively connected with the engine via the flywheel body, a hydraulic motor unit having a motor shaft serving as a main-output shaft and outputting drive power through said motor shaft with the speed of the drive power non-stepwisely changed in cooperation with the hydraulic pump unit, and a center section for supporting the hydraulic pump unit and the hydraulic motor unit and provides fluid connection therebetween; the engine, the flywheel housing and the HST are integrally connected with each other so as to vibrate freely relative to a vehicle frame and disposed at a distance from the sub-speed-change unit closer to one end of said working vehicle than to said sub-speed-change unit; the sub-speed-change unit includes a sub-input shaft and a sub-output shaft; and the motor shaft of the HST is operatively coupled with the sub-input shaft of the sub-speed-change unit via a shaft coupling. 8. A transmission for a working vehicle according to claim 7, wherein said shaft coupling is vibration-absorbing.9. A transmission for a working vehicle according to claim 1, wherein the flywheel housing includes a PTO shaft, to which drive power from the engine is selectively transmitted by engagement and disengagement of clutch means.10. A transmission for a working vehicle according to claim 9, wherein the main-output shaft and the PTO shaft are aligned parallel to each other in a vehicle's lateral direction.11. A transmission for a working vehicle according to claim 7, wherein:the flywheel housing includes a body portion having an accommodation space and opposite open ends, and a partition wall for dividing said accommodation space into a dry chamber for accommodating the flywheel body and a hydraulic fluid chamber for accommodating the HST; and the flywheel body has a portion facing said partition wall, on which an airflow fan is provided. 12. A transmission for a working vehicle according to claim 11, wherein one of the opposite open ends of the flywheel housing, which is located dower to the hydraulic fluid chamber, is covered by the center section.13. A transmission for a working vehicle according to claim 11, wherein:the hydraulic pump unit and the hydraulic motor unit are supported on an upstream side of the center section; the pump shaft of the hydraulic pump unit has a downstream end extending downstream through a downstream side of the center section; and the downstream end of the pump shaft is provided with a charge pump for replenishing operating fluid in the HST. 14. A transmission for a working vehicle according to claim 13, wherein the downstream end of the pump shaft if further provided with an auxiliary pump for feeding operating fluid to an outside actuator.15. A transmission for a working vehicle according to claim 11, wherein:the hydraulic pump unit and the hydraulic motor unit are respectively supported on upstream and downstream sides of the center section; and the upstream end of the pump shaft in the hydraulic pump unit has a portion located in the dry chamber, said portion being provided with a charge pump for replenishing operating fluid in the HST. 16. A transmission for a working vehicle according to claim 15, wherein:a downstream end of the pump shaft extends downstream through the center section; and a housing for accommodating the sub-speed-change unit is further provided, said housing including a power transmission shaft operatively coupled with the downstream end of the pump shaft via a vibration-absorbing shaft coupling, and an auxiliary pump for feeding operating fluid to an outside actuator, which is driven by drive power branched from said power transmission shaft. 17. A vehicle with a power transmission train for transmitting drive power from an engine to a driving axle via a main-speed-change unit and a sub-speed-change unit wherein:said engine is disposed on a vehicle frame closer to a first side thereof in a fore and aft direction of the vehicle; the main-speed-change unit is integrally disposed with a flywheel housing that is connected with a downstream side of said engine; the sub-speed-change unit is disposed on the vehicle frame closer to a second side thereof in the fore and aft direction of the vehicle at a distance from said flywheel housing; and the main-speed-change unit is operatively coupled with the sub-speed-change unit via a coupling shaft that extends in the fore and aft direction of the vehicle. 18. A vehicle according to claim 17, whereinthe engine, the flywheel and the main-speed-change unit are mounted on the vehicle frame so as to vibrate relative to the vehicle frame, and the sub-speed-change unit is mounted on the vehicle frame so as not to vibrate relative to the vehicle frame; and the main-speed-change unit is operatively coupled with the sub-speed-change unit via a vibration-absorbing shaft coupling. 19. A vehicle according claim 17, wherein the flywheel housing includes a boy portion having an accommodation space and opposite open ends, and a partition wall for dividing said accommodation space into a first chamber and a second chamber, the former located closer to the first side of the fore and aft direction of the vehicle, and the latter located closer to the second side of the fore and aft direction of the vehicle, in which the first chamber accommodates a flywheel body of the flywheel and the second chamber accommodates the main-speed-change unit.20. A vehicle according to claim 19, wherein the flywheel body has a facing said partition wall, on which an airflow fan is provided.21. A vehicle with a power transmission train for transmitting drive power from an engine, to a driving axle via a flywheel, an HST and a sub-speed-change unit wherein:said engine is disposed on a vehicle frame closer to a first side thereof in a fore and aft direction of the vehicle; said flywheel including a flywheel body operatively connected with the engine and, a flywheel housing connected with a side of the engine facing a second side of the vehicle frame in the fore and aft direction of the vehicle so as to accommodate said flywheel body; the HST is integrally disposed with the flywheel housing; the sub-speed-change unit is disposed on the vehicle frame closer to the second side of the vehicle frame in the fore and aft direction of the vehicle at a distance from the flywheel housing; and the HST is operatively coupled with the sub-speed-change unit via a coupling shaft that extends in the fore and aft direction of the vehicle. 22. A vehicle according to claim 21, wherein:the engine, the flywheel and the HST are mounted on the vehicle frame so as to vibrate relative to the vehicle frame, and the sub-speed-change unit is mounted on the vehicle frame so as not to vibrate relative to the vehicle frame; and the HST is operatively coupled with the sub-speed-change unit via a vibration-absorbing shaft coupling. 23. A vehicle according to claim 17, wherein the flywheel housing is provided with a PTO shaft capable of transmitting drive power from the engine to the outside of said flywheel housing via clutch means.