초록 ▼

A system for controlling the engagement and disengagement of one or more clutches that are adapted to operatively connect an engine and an automatic transmission includes a control device for determining if a negative torque condition exists and for providing an output or signal to decrease the rota

A system for controlling the engagement and disengagement of one or more clutches that are adapted to operatively connect an engine and an automatic transmission includes a control device for determining if a negative torque condition exists and for providing an output or signal to decrease the rotational speed of the engine in response to the determination of the existence of the negative torque condition.

대표청구항 ▼

What is claimed: 1. A system for controlling engagement and disengagement of one or more clutches that are adapted to operatively connect an engine and an automatic transmission of a vehicle, the system comprising: a torque convener coupling an engine to an automatic transmission having one or more

What is claimed: 1. A system for controlling engagement and disengagement of one or more clutches that are adapted to operatively connect an engine and an automatic transmission of a vehicle, the system comprising: a torque convener coupling an engine to an automatic transmission having one or more gear-selection clutches, a control device configured to obtain or receive a rotational speed of said engine, to obtain or receive a rotational speed of said automatic transmission, and to determine if a negative torque condition exists, wherein the control device causes selective disengagement of each one of said one or more clutches putting said automatic transmission in neutral gear in response to a determination that the negative torque condition exists. 2. The system according to claim 1, wherein the negative torque condition is determined to exist when the rotational speed of said transmission is greater than the rotational speed of said engine. 3. The system according to claim 1, wherein the control device is further configured to determine if the negative torque condition no longer exists and wherein said one or more clutches are selectively re-engaged putting said transmission into gear in response to a determination that the negative torque condition no longer exists. 4. The system according to claim 3, wherein said one or more clutches are selectively pressurized to a select or predetermined pressure during the presence of the negative torque condition prior to re-engagement to said automatic transmission. 5. The system according to claim 1, further including a sensor adapted to signal or determine an actuation of an accelerator pedal or a deactivation of the accelerator pedal. 6. The system according to claim 5. wherein the deactivation of the accelerator pedal is a parameter used by the control device to determine the existence of the negative torque condition. 7. The system according to claim 1, further including a sensor for signaling or determining actuation or deactivation of a brake pedal. 8. The system according to claim 7, wherein the actuation of the brake pedal is a parameter used by the control device to determine the existence of the negative torque condition. 9. The system according to claim 1, wherein the control device is adapted to determine a vehicle speed, wherein the vehicle speed is a parameter used by the control device to determine the existence or absence of the negative torque condition. 10. The system according to claim 9. wherein the vehicle speed is used to calculate a vehicle acceleration, and wherein the vehicle acceleration is a parameter used by the system to signal engagement of said one or more clutches. 11. A system for controlling the engagement and disengagement of a clutch adapted to operatively connect an engine and an automatic transmission, the system comprising: a torque convener coupling an engine to an automatic transmission, a control device comprised of an engine controller and a transmission controller; an engine speed sensor in communication with the engine controller and adapted to provide a signal associated with a current rotational speed of said engine; and a torque converter turbine output shaft sensor in communication with the transmission controller and adapted to provide a signal associated with a current rotational speed of said transmission; wherein the control device determines whether a negative torque condition exists based upon signals Or information received from or provided by the engine controller and the transmission controller, and wherein said clutch selectively disengages said automatic transmission putting the automatic transmission into neutral gear, when the control device determines or signals the existence of the negative torque condition. 12. The system according to claim 11, wherein the negative torque condition exists when the control device determines the current rotational speed of said transmission is greater than the current rotational speed of said engine based upon signals or information provided by the engine controller and the transmission controller. 13. The system according to claim 11, further including a vehicle speed sensor in communication with the control device, wherein die speed sensor is adapted to determine or signal a current vehicle speed, including when the vehicle is experiencing a neutral coast condition. 14. The system according to claim 11, further including an accelerator pedal sensor in communication with the engine controller, wherein the accelerator pedal sensor is adapted to signal or determine a position or degree of depression of an accelerator pedal; the control device is adapted to determine the existence or absence of a neutral coast condition based, in part, upon parameters received from the accelerator pedal sensor; and said clutch is selectively engaged or disengaged based upon the neutral coast condition. 15. The system according to claim 11, further including a brake pedal sensor in communication with the control device, wherein the brake pedal sensor is adapted to signal or determine a position or degree of depression of a brake pedal; the control device is adapted to determine the existence or absence of a neutral coast condition based upon parameters received from the brake pedal sensor; and said clutch is selectively engaged or disengaged based upon the existence of the neutral coast condition. 16. The system according to claim 11, wherein said clutch is selectively pressurized to a select or predetermined pressure during the existence of the negative torque condition prior to re-engagement to the automatic transmission and said clutch is re-engaged putting the automatic transmission into gear when the negative torque condition no longer exists. 17. A method of controlling engagement and disengagement of one or more clutches for a powertrain system of a vehicle comprising; (a) providing a (1) powertrain system that comprises an automatic transmission coupled by a torque convener to an engine with the automatic transmission having a plurality of gear-selection clutches, and (2) a control device monitoring operation of the engine and transmission that comprises at least one of a transmission controller and an engine controller; (b) determining whether a negative torque condition exists; (c) releasing each one of die plurality of gear-selection clutches if the negative torque condition is determined to exist, putting the automatic transmission into a neutral gear condition; (d) lowering speed of the engine while the automatic transmission is in the neutral gear condition; and (e) re-engaging at least one of the plurality of gear-selection clutches putting the automatic transmission into gear upon determining that the negative torque condition no longer exists. 18. The method according to claim 17, wherein the control device comprises an engine controller and step (d) comprises sending of a signal from the engine controller to lower the speed of the engine. 19. The method according to claim 17, wherein the negative torque condition exists when a current rotational speed of said automatic transmission is higher than a current rotational speed of said engine, and wherein the releasing each one of the plurality of gear-selection clutches if the negative torque condition is determined to exist in step (c) causes each engaged gear-selection clutch to disengage from said automatic transmission putting said automatic transmission into neutral gear. 20. The method according to claim 17, farther including an electronic throttle control for signaling or providing a position or degree of opening of an engine throttle and a vehicle speed sensor for signaling or providing a vehicle speed, wherein an appropriate one or more of the clutches is selected and released in step (c) based upon signals or input provided by the electronic throttle control and the vehicle speed sensor. 21. The method according to claim 17, wherein before step (e), comprising the further step of applying a select or predetermined amount of pressure to an appropriate one of the gear-selection clutches during the existence of the negative torque condition and comprising during step (e) applying pressure to re-engage at least one of the plurality of gear-selection clutches when a rate of acceleration of the vehicle exceeds a select or predetermined amount putting the automatic transmission of the powertrain system into gear.