AUTOMATIC TRANSMISSION CONTROL DEVICE
First Claim
1. An automatic transmission control device configured to start an increase in engagement pressure of a start-up engagement element when a determination threshold value for determining that an input shaft rotational speed of an automatic transmission has been determined to have reduced is reached or exceeded, characterized in that,the determination threshold value when a selection operation from a non-traveling range to a traveling range is made before a prescribed period of time from starting of an engine has elapsed, is increased and set greater than the determination threshold value when the selection operation is made after the prescribed period of time has elapsed.
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Accused Products
Abstract
In an automatic transmission control device of the invention configured to start an increase in engagement pressure of a start-up engagement element, when a determination threshold value for determining that a turbine rotational speed has reduced is reached or exceeded, the determination threshold value when a selection operation from a non-traveling range to a traveling range is made before a prescribed period of time from starting of an engine has elapsed, is increased and set greater than the determination threshold value when the selection operation is made after the prescribed period of time has elapsed. Accordingly, a reduction in the turbine rotational speed can be accurately determined, and thus it is possible to suppress torque fluctuations, occurring owing to engagement of a second brake, which is the start-up engagement element.
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Citations
4 Claims
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1. An automatic transmission control device configured to start an increase in engagement pressure of a start-up engagement element when a determination threshold value for determining that an input shaft rotational speed of an automatic transmission has been determined to have reduced is reached or exceeded, characterized in that,
the determination threshold value when a selection operation from a non-traveling range to a traveling range is made before a prescribed period of time from starting of an engine has elapsed, is increased and set greater than the determination threshold value when the selection operation is made after the prescribed period of time has elapsed.
Specification