Patent ID: 8050827
Filing Date: 2011-11-01
Classification: F16H,Y10T

Abstract:
1. A vehicle transmission system for transmitting power from a prime mover to an axle, comprising: a speed-changing mode setting means, wherein a reverse mode can be set by the speed-change mode setting means; a reversing operation member that is shiftable between a forward traveling position and a backward traveling position; and a multi-speed transmission including: an input portion for receiving power from the prime mover; an output portion for outputting power to the axle; a first drive train group including odd-numbered speed drive trains for forward-traveling; an odd-numbered speed shifter for selecting one odd-numbered speed drive train to be ready for transmitting power from the input portion to the output portion; a first clutch for the first drive train group, wherein when the odd-numbered speed shifter selects one of the odd-numbered speed drive trains and the first clutch is engaged, power of the input portion is transmitted to the output portion via the selected odd-numbered speed drive train and the engaged first clutch; a second drive train group including even-numbered speed drive trains for forward-traveling; an even-numbered speed shifter for selecting one even-numbered speed drive train to be ready for transmitting power from the input portion to the output portion; a second clutch for the second drive train group, wherein when the even-numbered speed shifter selects one of the even-numbered speed drive trains and the second clutch is engaged, power of the input portion is transmitted to the output portion via the selected even-numbered speed drive train and the engaged second clutch, and wherein, when the clutch-engagement is shifted between the first and second clutches, an engagement action of one of the first and second clutches and a disengagement action of the other of the first and second clutches overlap; a backward traveling drive train belonging to either the first or second drive train group, wherein the first or second clutch for the first or second drive train group including the backward traveling drive train serves as a backward traveling clutch; a backward traveling shifter for selecting the backward traveling drive train to be ready for transmitting power from the input portion to the output portion, wherein, when the backward traveling shifter selects the backward traveling drive train and the backward traveling clutch is engaged, power of the input portion is transmitted to the output portion via the selected backward traveling drive train and the engaged backward traveling clutch, and wherein, when the reverse mode is set by the speed-changing mode setting means, the backward traveling drive train is selected by the backward traveling shifter, and one odd or even numbered speed drive train belonging to the first or second drive train group that does not include the backward traveling drive train is selected by the corresponding odd or even numbered speed shifter so as to be defined as a forward traveling drive train selected in the reverse mode, so that, when the reversing operation member is set at the forward traveling position, the first or second clutch that does not serve as the backward traveling clutch is engaged and the first or second clutch that serves as the backward traveling clutch is disengaged so as to transmit power from the input portion to the output portion via the forward traveling drive train selected in the reverse mode, and so that, when the reversing operation member is set at the backward traveling position, the first or second clutch that serves as the backward traveling clutch is engaged and the first or second clutch that does not serve as the backward traveling clutch is disengaged so as to transmit power from the input portion to the output portion via the selected backward traveling drive train.