Patent ID: 7694602
Filing Date: 2010-04-13
Classification: F16H,Y10T

Abstract:
1. An automatic transmission apparatus for a vehicle, comprising: a shift lever which is provided as being capable of being operated to move to a plurality of positions, wherein the shift lever is configured to switch ranges of an automatic transmission by being operated to move to each position; a position gate configured to restrict the position of the shift lever, and is configured to release the restriction to allow the shift lever to change positions when an operation button provided on the shift lever is pressed; an operation force detector configured to detect an operation force on the shift lever; and a controller configured to determine whether a power-assist control is to be carried out according to a detected value of the operation force detector, and is configured to drive a motor to provide a power assist to help the operation of the shift lever in a case where the power-assist control is actually carried out, wherein the controller is configured to set a lower limit of a driving force of the motor to a positive value near zero when the detected value of the operation force detector is greater than a predetermined positive threshold value, and to set an upper limit of the driving force of the motor to a negative value near zero when the detected value of the operation force detector is less than a predetermined negative threshold value, to prevent a reversal of the power-assist direction due to the detected value of the operation force detector being reversed to a positive value or a negative value, the reversal of the detected value of the operation force detector being caused in a case where the shift lever is operated without releasing the restriction by the position gate, and where the shift lever is then operated to hit the position gate.