Patent ID: 8046141
Filing Date: 2011-10-25
Classification: F16H

Abstract:
1. An automatic gear shifting control device of a vehicle, comprising: a control part that is configured to execute an automatic gear shifting operation of a transmission in response to at least vehicle speed; a first sensor that detects a rotational speed of a front wheel which constitutes a driven wheel; a second sensor that detects a rotational speed of a rear wheel, which constitutes a driven wheel; and a rotational-speed-difference detector that is configured to detect a difference in rotational speed between the front wheel and the rear wheel based on information from the first sensor and information from the second sensor, wherein the control part is configured to execute an automatic gear shifting control in response to the vehicle speed, the vehicle speed calculated based on the rotational speed of the front wheel when the front wheel has a greater rotational speed than the rear wheel and calculated based on the rotational speed of the rear wheel when the rear wheel has a greater rotational speed than the front wheel, wherein when the rotational speed of the rear wheel decreases to create a difference in rotational speed between the front and rear wheels, the automatic gear shifting control is executed toward a lower gear side from a change gear ratio on the rotational speed of the front wheel, wherein when the front wheel is locked or the rotational speed of the front wheel is lower than the rear wheel, the gear shifting control is executed toward the lower gear side from the change gear ratio on the rotational speed of the rear wheel, and wherein a gear shift toward a shift up side is executed until a difference in rotational speed between the front wheel and the rear wheel is no longer detected.