Patent ID: 9014932
Filing Date: 2015-04-21
Classification: B60W,B60Y,F16H

Abstract:
1. An automatic transmission including: a plurality of first rotating shafts including an input-side first rotating shaft to which motive power is input from a prime mover; a plurality of first transmission gear trains that are provided on said plurality of first rotating shafts, for forming a first power transmission path for transmitting the motive power from the prime mover to driven parts, in cooperation with said plurality of first rotating shafts, said plurality of first transmission gear trains setting a plurality of speed positions, respectively; a first synchronization mechanism that connects between one transmission gear out of said plurality of first transmission gear trains and one rotating shaft out of said plurality of first rotating shafts with each other while synchronizing the one transmission gear and the one rotating shaft with each other, thereby making it possible to transmit the motive power from the prime mover to the driven parts via the first power transmission path while changing a speed of the motive power, and releases the connection between the one transmission gear and the one rotating shaft; a first clutch that connects and disconnects between the prime mover and said input-side first rotating shaft; a plurality of second rotating shafts including an input-side second rotating shaft to which the motive power is input from the prime mover; a plurality of second transmission gear trains that are provided on said plurality of second rotating shafts, for forming a second power transmission path for transmitting the motive power from the prime mover to the driven parts, which is different from the first power transmission path, in cooperation with said plurality of second rotating shafts, said plurality of second transmission gear trains setting a plurality of speed positions, respectively; a second synchronization mechanism that connects between one transmission gear of said plurality of second transmission gear trains and one rotating shaft of said plurality of second rotating shafts with each other while synchronizing the one transmission gear and the one rotating shaft with each other, thereby making it possible to transmit the motive power from the prime mover to the driven parts via the second power transmission path while changing a speed of the motive power, and releases the connection between the one transmission gear and the one rotating shaft; a second clutch that connects and disconnects between the prime mover and said input-side second rotating shaft; and control means for setting a power transmission path for transmitting the motive power from the prime mover to the driven parts, to one of the first power transmission path and the second power transmission path, by controlling one of said first clutch and said second clutch to an engaged state and the other of said first clutch and said second clutch to a disengaged state, and controlling one of said first synchronization mechanism and said second synchronization mechanism to a connecting state and the other of said first synchronization mechanism and said second synchronization mechanism to a releasing state, said control means performing, to change a speed position, switching control for switching the power transmission path from the one to the other of the first power transmission path and the second power transmission path, by switching between the engaged state and the disengaged state of the one and the other of said first clutch and said second clutch and between the connecting state and the releasing state of the one and the other of said first synchronization mechanism and said second synchronization mechanism, and executing, when performing the switching control, pre-shift control in which while holding the one clutch in the engaged state, the one synchronization mechanism in the connecting state, and the other clutch in the disengaged state, the other synchronization mechanism is caused to shift from the releasing state to the connecting state, wherein said control means comprises: execution condition-determining means for determining whether or not execution conditions for executing the pre-shift control are satisfied, before executing the switching control; motive power fluctuation-causing condition-determining means for determining, based on a result of determination by said execution condition-determining means, when the execution conditions for executing the pre-shift control are satisfied, whether or not there are satisfied motive power fluctuation-causing conditions from which a predetermined motive power fluctuation state of the prime mover is estimated to occur after satisfaction of the executing conditions; and pre-shift control execution means for performing, based on a result of determination by said motive power fluctuation-causing condition-determining means, to execute delay control for delaying a start of the pre-shift control when the motive power fluctuation-causing conditions are satisfied, and to start the pre-shift control without executing the delay control when the motive power fluctuation-causing conditions are not satisfied.