Automitic transmission

Abstract

The object of the present invention is to dissolve the shock originated from engaging and disengaging of the clutch during acceleration, when using a mesh type transmission provided with a clutch for engaging and disengaging the shift gear and the output shaft. A mesh type automatic transmission equipped with a plurality of shift gears 11, 13, 14 provided so as to rotate freely to an output shaft 5 for providing driving force to the wheels, a plurality of cogged clutches 12, 15 engaging with the output shaft 5, and a plurality of counter shift gears 8, 9, 10 corresponding to each speed, which are fixed to a counter shaft 6 rotated by the rotation of an input shaft 3 rotated from the power of an engine 43, and which mesh with the plurality of shift gears 11, 13, 14, for performing automatic shifting by controlling engagement of one of the plurality of cogged clutches 12, 15 with the voluntary shift gears of the plurality of shift gears 11, 13, 14 determined from the accelerator command value and the vehicle speed, is used. The automatic transmission is provided with an assist mechanism for transmitting the rotational force of the input shaft 3 to the output shaft 5 via the assist shaft 31 which rotates from the rotation of the counter shaft 6, when no cogged clutch of the plurality of cogged clutches 12, 15 is engaged with any of the plurality of shift gears 11, 13, 14, occurring during switching when an engaged cogged clutch of the plurality of cogged clutches 12, 15 is disengaged and one of the cogged clutch of the plurality of cogged clutches 12, 15 is to be engaged.

We claim:  
     
         1 . A mesh type transmission for transmitting power of an input shaft to an output shaft by engaging a plurality of cogged clutches with a plurality of shift gears, which is an automatic transmission for performing automatic shifting by controlling engagement of said plurality of cogged clutches for engaging and disengaging said voluntary shift gear with said output shaft; wherein. 
 an assist mechanism for transmitting rotational force of said input shaft to said output shaft, in the period when no cogged clutch is engaged with any of said plurality of shift gears, during switching of said cogged clutch, is provided thereto.    
     
     
         2 . A mesh type automatic transmission equipped with an output shaft for outputting drive force, a plurality of shift gears, a plurality of cogged clutches, an input shaft for introducing power of an engine, a counter shaft, and a plurality of counter gears, for transmitting rotation of said counter shaft being rotated by rotation of said input shaft which is rotated by the power of said engine, to said output shaft via said counter gear with automatic shifting, by engaging said cogged clutch with said shift gear corresponding to speed; wherein 
 an assist mechanism for transmitting rotational force of said input shaft to said output shaft by said assist shaft, by transmitting rotation of said counter shaft to said assist shaft via said assist gear, in the period when one of said gear is disengaged and a new gear is to be engaged during said shifting, is provided thereto.    
     
     
         3 . An automatic transmission according to  claim 2 , wherein said assist mechanism is provided so that said assist shaft is deviated from a line connecting a central axis of said counter shaft rotated by the power of said input shaft, with a central axis of said output shaft which is engaged with said plurality of cogged clutches, is fit with said plurality of shift gears so as to rotate freely, and which outputs rotation of said counter shaft with gear shifted according to need, and a central axis of said assist shaft is positioned below said central axis of said counter shaft.  
     
     
         4 . A mesh type automatic transmission equipped with an output shaft for outputting drive force to a plurality of wheels, a plurality of shift gears, a plurality of cogged clutches, an input shaft for introducing power of an engine, a counter shaft, and a plurality of counter gears, for transmitting rotation of said counter shaft being rotated by rotation of said input shaft which is rotated by the power of said engine, to said output shaft via said counter gear with automatic shifting, by engaging said cogged clutch; with said shift gear corresponding to speed; wherein 
 an assist mechanism for transmitting rotational force of said input shaft to said output shaft by said assist shaft, by transmitting rotation of said counter shaft to said assist shaft via said assist gear, in the period when one of said gear is disengaged and a new gear is to be engaged during said shifting, is provided inside a transmission case on the side of a gear oil injection hole, and is provided so that said assist shaft is provided to the position below a line perpendicular to a line connecting a central axis of said output shaft with a central axis of said counter shaft at the center of said output shaft.    
     
     
         5 . A mesh type automatic transmission equipped with an output shaft for outputting drive force to a plurality of wheels, a plurality of shift gears, a plurality of cogged clutches, an input shaft for introducing power of an engine, a counter shaft, and a plurality of counter gears, for transmitting rotation of said counter shaft being rotated by rotation of said input shaft which is rotated by the power of said engine, to said output shaft via said counter gear with automatic shifting, by engaging said cogged clutch with said shift gear corresponding to speed; wherein 
 an assist mechanism for transmitting rotational force of said input shaft to said output shaft by said assist shaft, by transmitting rotation of said counter shaft to said assist shaft via said assist gear, in the period when one of said gear is disengaged and a new gear is to be engaged during said shifting, is provided so that said assist shaft is positioned on the opposite side of said output shaft relative to a horizontal line passing the center of said counter shaft.    
     
     
         6 . A mesh type automatic transmission equipped with an output shaft for outputting drive force to a plurality of wheels, a plurality of shift gears, a plurality of cogged clutches, an input shaft for introducing power of an engine, a counter shaft, and a plurality of counter gears, for transmitting rotation of said counter shaft being rotated by rotation of said input shaft which is rotated by the power of said engine, to said output shaft via said counter gear with automatic shifting, by engaging said cogged clutch with said shift gear corresponding to speed; wherein 
 an assist mechanism for transmitting rotational force of said input shaft to said output shaft by said assist shaft, by transmitting rotation of said counter shaft to said assist shaft via said assist gear, in the period when one of said gear is disengaged and a new gear is to be engaged during said shifting, is provided to the position opposite to the side of an engine and a starting clutch, based on the position of said counter shaft.    
     
     
         7 . A mesh type automatic transmission equipped with an output shaft for outputting drive force to a plurality of wheels, a plurality of shift gears, a plurality of cogged clutches, an input shaft for introducing power of an engine, a counter shaft, and a plurality of counter gears, for transmitting rotation of said counter shaft being rotated by rotation of said input shaft which is rotated by the power of said engine, to said output shaft via said counter gear with automatic shifting, by engaging said cogged clutch with said shift gear corresponding to speed; wherein 
 an assist mechanism for transmitting rotational force of said input shaft to said output shaft by said assist shaft, by transmitting rotation of said counter shaft to said assist shaft via said assist gear, in the period when one of said gear is disengaged and a new gear is to be engaged during said shifting, is provided so that said assist shaft is provided on the opposite side of said output shaft relative to a horizontal axis passing the center of said counter shaft, as well as to the position opposite to the side of an engine and a starting clutch, based on the position of said counter shaft.    
     
     
         8 . An automatic transmission according to any of claims  2 ,  3 ,  4 ,  5 ,  6  or  7 ; wherein said assist mechanism starts engaging when a switch command for said cogged clutch is output, before said cogged clutch currently engaged with said shift gear is completely disengaged, engages according to torque of said engine and transmits rotational force of said input shaft to said output shaft, when said cogged clutch is completely disengaged from said engaged shift gear, and disengages when said cogged clutch is engaged with said shift gear to be engaged based on said switch command.  
     
     
         9 . An automatic transmission according to any of claims  2 ,  3 ,  4 ,  5 ,  6 ,  7  or  8 ; wherein said assist mechanism comprising said assist shaft rotating from the rotational force of said counter shaft, said assist input gear meshing with said counter assist gear fixed to said counter shaft and being mounted to said assist shaft so as to rotate freely, said assist output gear meshing with said counter gear of the highest gear mounted to said counter shaft so as to rotate freely and being fixed to said assist shaft, and said assist clutch for engaging said assist input gear with said counter shaft, transmits rotation of said assist input gear to said output shaft via said assist shaft and said assist output gear, based on an assist command.