Control apparatus of lock-up clutch for vehicle and control method thereof
AssigneeToyota Jidosha Kabushiki Kaisha
InventorsTakuya Ito, Hiroaki Takeuchi
Life of this patent
Estimating the term…
Abstract
When a deceleration slip executing minimum gear stage is not established in a state of continuously executing a deceleration slip control at a target slip amount, it is judged whether or not an input shaft rotational speed of a transmission becomes a down shift judging rotational speed. When it becomes equal to or less than a predetermined down shift judging rotational speed, a down shift is executed, and a clutch pressure is controlled such that an engine rotational speed becomes a target engine rotational speed.
Claims14
A control apparatus of a lock-up clutch for a vehicle having a hydraulic power transmission with a lock-up clutch which directly connects between an engine and an automatic transmission, the control apparatus comprising:
- a fuel-cut control portion stopping supplying a fuel to the engine at a time when the vehicle is decelerated, and restarting supplying the fuel to the engine at a time of judging that a rotational speed of the engine becomes a predetermined fuel-cut end rotational speed;
- a slip control portion which executes a slip control of the lock-up clutch at the time when the vehicle is decelerated;
- and
- a shift transmission control portion which performs a down shift of the automatic transmission at a time of judging that at least any one of the rotational speed of the engine and an input shaft rotational speed of the automatic transmission becomes a down shift rotational speed which is higher than the fuel-cut end rotational speed by a predetermined amount, during an execution of the slip control by the slip control portion.
A control apparatus of a lock-up clutch for a vehicle having a lock-up clutch which directly connects between an engine and an automatic transmission, the control apparatus comprising:
- a slip control portion increasing a fuel-cut time required from a start of a fuel-cut at which a fuel supply to the engine is stopped and until an engine rotational speed reaches a fuel-cut end rotational speed, by slip controlling the lock-up clutch at a deceleration of the vehicle;
- and
- a shift transmission control portion which increases the fuel-cut time by shifting down the automatic transmission immediately before the engine rotational speed reaches the fuel-cut end rotational speed.
A control method of a lock-up clutch for a vehicle having a hydraulic power transmission with a lock-up clutch which directly connects between an engine and an automatic transmission, comprising:
- a step of stopping supplying a fuel to the engine at a deceleration of the vehicle, and restarting supplying the fuel to the engine at a time of judging that a rotational speed of the engine becomes a predetermined fuel-cut end rotational speed;
- a step of executing a slip control of the lock-up clutch at the deceleration of the vehicle;
- and
- a step of shifting down the automatic transmission at a time of judging that at least any one of the rotational speed of the engine and an input shaft rotational speed of the automatic transmission becomes a down shift rotational speed which is higher than the fuel-cut end rotational speed by a predetermined amount, during an execution of the slip control.
A control method of a lock-up clutch for a vehicle having a lock-up clutch which directly connects between an engine and an automatic transmission, comprising:
- a step of increasing a fuel-cut time required from a start of a fuel-cut at which a fuel supply to the engine is stopped and until an engine rotational speed reaches a fuel-cut end rotational speed, by slip controlling the lock-up clutch at a deceleration of the vehicle;
- and
- a step of increasing the fuel-cut time by shifting down the automatic transmission immediately before the engine rotational speed reaches the fuel-cut end rotational speed.
Dependencies are inferred from the claim text.