Patent ID: 7222551

Claim:
A mesh-type automatic transmission, comprising a power input shaft for introducing engine power, a plurality of transmission gears, a plurality of cogged clutches, a power output shaft for outputting driving force, a counter shaft, and a plurality of counter gears for transmitting the engine power to said power output shaft by rotating said power input shaft via the engine power, rotating said counter shaft by rotation of said power input shaft, and transmitting rotation of said counter shaft to said power output shaft via said counter gear automatically by engaging and disengaging said cogged clutch to one of said transmission gears corresponding to speed; wherein said counter shaft is provided with an assist mechanism for transmitting rotational force of said power input shaft to said power output shaft by transmitting rotation of said counter shaft via said assist mechanism during a gear change from the time of disengagement of a gear to the engagement of a new gear, said assist mechanism including an assist clutch having an assist counter shaft, an assist gear associated and rotatable with said assist counter shaft, and an assist output gear operatively associated with the power output shaft, wherein said assist mechanism starts engaging when a switch command of said cogged clutch is output before said cogged clutch currently engaged with said transmission gear is completely disengaged, transmits the rotational force of said power input shaft to said power output shaft by being engaged corresponding to the torque of the engine when said cogged clutch is completely disengaged from said engaged transmission gear, and disengages when said cogged clutch is engaged with said transmission gear to be engaged based on said switch command.