Abstract: A method of controlling an automatic transmission of a motor vehicle operating in a automatic speed control speed mode is provided. The first step in the method is measuring the torque output of the engine. A torque load acting on the transmission in a first gear is then determined. A maximum torque capable of being produced by the engine is then predicted. A torque output of the transmission in a second gear is then determined based upon the predicted maximum torque capable of being produced by the engine. A transmission shift from the first gear to the second gear is then allowed if the determined torque output of the transmission in the second gear is greater than the torque load of the transmission in a first gear.

Abstract: A method of controlling an automatic transmission of a motor vehicle operating in a automatic speed control speed mode is provided. The first step in the method is measuring the torque output of the engine. A torque load acting on the transmission in a first gear is then determined. A maximum torque capable of being produced by the engine is then predicted. A torque output of the transmission in a second gear is then determined based upon the predicted maximum torque capable of being produced by the engine. A transmission shift from the first gear to the second gear is then allowed if the determined torque output of the transmission in the second gear is greater than the torque load of the transmission in a first gear.

Abstract: A method of shifting in a manual mode of an electronically-controlled automatic transmission system includes the steps of determining whether a shift lever of a shift lever mechanism is presenting a position error when the shift lever is in a manual position, determining whether at least one switch on the shift, lever mechanism is presenting an error if a shift lever position, error is not determined, determining whether a temperature of an, automatic transmission or engine coolant temperature exceeds a predetermined threshold if the at least one switch is not presenting an error, determining whether the manual position conditions have been met, determining whether an upshift or downshift of the automatic transmission is scheduled if the manual position conditions have been met, and executing either an upshift or a downshift of the automatic transmission based on the determined upshift or downshift being scheduled.

Abstract: A four-speed automatic transmission for a vehicle includes a transmission housing, an input member, an output member, three planetary gearsets for changing a ratio of torque between the input member and the output member, a plurality of clutch assemblies to selectively couple the input member to predetermined gears of the planetary gearsets, a plurality of brake assemblies to selectively couple predetermined gears of the planetary gearsets to the transmission housing, and a structure for allowing the output member and a planetary carrier from one of the planetary gearsets and an annulus gear of another of the planetary gearsets to rotate simultaneously.

Abstract: An interactive cruise control system and method for providing automatic speed control of a vehicle with improved shifting of an automatic transmission. The system and method controls speed of a vehicle equipped with cruise control and minimizes downshifts in an automatic transmission of the vehicle. Vehicle speed is detected and compared with a setpoint speed which is associated with the cruise control system. Transmission gear shifting is determined based on predetermined shift schedule points. Determined transmission gear downshifts are prevented for a kickdown delay period based on vehicle speed loss and the presence of vehicle deceleration. Also provided is an overspeed reduction method for causing a transmission downshift during an overspeed condition with the throttle closed. Further, the system provides hunting prevention between both second gear and third gear as well as between third gear and fourth gear for a four speed automatic transmission.

Abstract: An interactive cruise control system and method for providing automatic speed control of a vehicle with improved shifting of an automatic transmission. The system and method controls speed of a vehicle equipped with cruise control and minimizes downshifts in an automatic transmission of the vehicle. Vehicle speed is detected and compared with a setpoint speed which is associated with the cruise control system. Transmission gear shifting is determined based on predetermined shift schedule points. Determined transmission gear downshifts are prevented for a kickdown delay period based on vehicle speed loss and the presence of vehicle deceleration. Also provided is an overspeed reduction method for causing a transmission downshift during an overspeed condition with the throttle closed. Further, the system provides hunting prevention between both second gear and third gear as well as between third gear and fourth gear of a four speed automatic transmission.

Abstract: A method of shifting in a manual mode of an electronically-controlled automatic transmission system includes the steps of determining whether a shift lever of a shift lever mechanism is presenting a position error when the shift lever is in a manual position, determining whether at least one switch on the shift lever mechanism is presenting an error if a shift lever position error is not determined, determining whether a temperature of an automatic transmission or engine coolant temperature exceeds a predetermined threshold if the at least one switch is not presenting an error, determining whether the manual position conditions have been met, determining whether an upshift or downshift of the automatic transmission is scheduled if the manual position conditions have been met, and executing either an upshift or a downshift of the automatic transmission based on the determined upshift or downshift being scheduled.

Abstract: An interactive cruise control system and method for providing automatic speed control of a vehicle with improved shifting of an automatic transmission. The system and method controls speed of a vehicle equipped with cruise control and minimizes downshifts in an automatic transmission of the vehicle. Vehicle speed is detected and compared with a setpoint speed which is associated with the cruise control system. Transmission gear shifting is determined based on predetermined shift schedule points. Determined transmission gear downshifts are prevented for a kickdown delay period based on vehicle speed loss and the presence of vehicle deceleration. Also provided is an overspeed reduction method for causing a transmission downshift during an overspeed condition with the throttle closed. Further, the system provides hunting prevention between both second gear and third gear as well as between third gear and fourth gear of a four speed automatic transmission.

Abstract: A method of determining the deterioration of automatic transmission fluid by detecting shudder during the EMCC portion of air conditioner clutch engagement. Shudder is detected by calculating the acceleration of the turbine during EMCC slip with the following equation:.SIGMA..alpha..sub.t =.SIGMA..alpha..sub.t (i-1)+.alpha..sub.twhere .alpha..sub.t represents the absolute value of turbine acceleration. In a preferred embodiment, the turbine acceleration is summed for twenty-eight periods of 7 msec each after the start of EMCC and the determination that shudder occurred made if the resulting value exceeds a predetermined number. In a further preferred embodiment, the method is used to modify the air conditioner compressor clutch engagement sequence. Once it is determined that shudder is occurring during the EMCC portion of the air conditioner compressor clutch engagement sequence, the EMCC portion of the air conditioner clutch engagement sequence is eliminated or bypassed.

Abstract: A four speed automatic transmission for a vehicle includes a transmission housing, an input member, an output member, three planetary gearsets for changing a ratio of torque between the input member and the output member, a plurality of clutch assemblies to selectively couple the input member to predetermined gears of the planetary gearsets, a plurality of brake assemblies to selectively couple predetermined gears of the planetary gearsets to the transmission housing, and a structure for allowing the output member and a planetary carrier from one of the planetary gearsets and an annulus gear of another of the planetary gearsets to rotate simultaneously.

Abstract: A five-speed automatic transmission for a vehicle includes a transmission housing, an input member, an output member, a plurality of planetary gearsets for changing a ratio of torque between the input member and the output member, a plurality of clutch assemblies to selectively couple the input member to predetermined gears of the planetary gearsets, a plurality of brake assemblies to selectively couple predetermined gears of the planetary gearsets to the transmission housing, and a structure for allowing the output member and a planetary carrier from one of the planetary gearsets and an annulus gear from another of the planetary gearsets and a sun gear from yet another of the planetary gearsets to rotate simultaneously.

Abstract: The present invention provides a method of adaptively modifying the transmission shift schedule during various driving conditions. The method determines a desirable upshift schedule based upon driving conditions, and adaptively adjusts the transmission shift schedule in accordance with a predefined criteria. This is accomplished by observing vehicle speed and other transmission operating parameters and determining whether an adaptive shift schedule adjustment is required. If the shift schedule is adaptively adjusted, the driving parameters are further monitored to determine at which time the shift schedule may be reset to its initial state.

Abstract: The present invention provides a method and apparatus for controlling the hydraulic line pressure in an automatic transmission for a vehicle in response to the torque transmitted through the transmission such that a minimum hydraulic line pressure is provided to the frictional elements to achieve a no-slip condition through the transmission increasing transmission efficiency, thereby increasing the fuel economy of the vehicle. Hydraulic line pressure is controlled by activating a solenoid activated valve which allows fluid recirculation from the high-pressure side of the hydraulic pump to the low-pressure side of the pump. Control signals are generated based on engine speed, turbine speed, output speed (vehicle speed), hydraulic line pressures, driver selected gear, the operating gear and the torque converter operating condition for energizing the solenoid-actuated valve.

Abstract: A method for predicting the temperature of automatic transmission fluid, in real time, in an automatic transmission. The method involves determining a constant for thermal inertia of the transmission, determining a torque converter heat flow, determining a transmission heat flow, determining a transmission cooler heat flow and determining an exterior-of-transmission heat flow. From each of the four above-mentioned heat flows and the above-mentioned constant, the transmission fluid temperature is predicted. The predicted temperature is used to modify operational parameters of the transmission such as its shift tables.

Abstract: A valve assembly in a fluid system of an automatic transmission for controlling the lock-up of the torque converter assembly of the automatic transmission includes a regulator valve for establishing a pressure level of fluid flow from a fluid source, a torque converter control valve for controlling fluid pressure to the torque converter assembly during the disengagement operating mode, and a lock-up valve receiving fluid pressure feedback from the torque converter control valve to close a fluid path during the disengagement operating mode and opening the fluid path for allowing fluid pressure to the apply side of the torque converter assembly during the engagement operating mode.

Abstract: A method of adaptively scheduling an upshift. The method determines whether the vehicle can maintain speed in a high gear and, if it cannot, to inhibit the lower to higher gear upshift. This is accomplished by observing vehicle acceleration in the lower gear, determining whether the vehicle will be capable of providing a predetermined value of acceleration after an upshift of the gear assembly to a higher gear. If the vehicle will not be capable of providing the predetermined value of acceleration, then the upshift will be prevented.

Abstract: A method is provided which controls the release element during a coastdown shift to prevent the release element from venting whenever slip is detected to ensure enough fluid volume to apply the release element if needed for an electronic automatic transmission system.

Abstract: An adaptive control system in an automatic four-speed transmission having a unique clutch and gear arrangement which eliminates the need for additional gearing and one over-running clutch, while requiring only one more friction element. The vehicle transmission assembly includes a transmission housing, a rotatable input member, an output member, and a gear assembly for changing the ratio of torque between the input member and the output member. Three clutch assemblies selectively couple the rotatable input member to predetermine gears of the gear assembly and two brake assemblies selectively couple predetermined gears of the gear assembly to the transmission housing. The gear assembly includes the first planetary gear set and a second planetary gear set.

Abstract: A method of calculating torque used in the initial percent on time of the solenoid-actuated valve for the release element such that when the speed change is complete, the actual acceleration approximately equals a desired turbine acceleration.

Abstract: The present invention is a hydraulic system for an automatic transmission having a torque converter for receiving power from a prime mover, and an assembly of hydraulically operated friction elements which provide clutch and brake functions. The hydraulic system includes a pump, a regulator valve, and a torque converter control valve for regulating fluid pressure to the torque converter. The hydraulic system also includes a manual valve and a plurality of solenoid valves for controlling fluid flow received at least in part from the manual valve to each of the friction elements. The hydraulic system further includes a switch valve operatively associated with the solenoid valve for enabling two of the friction elements to be controlled from only one of the solenoid valves.