Abstract: An assembly includes a valve body having an inlet in selective communication with an outlet and having an unlatch port, a latching piston disposed within the valve body, a balance spring disposed between the latching piston and the valve body, and a valve piston disposed within the valve body. The inlet communicates with the outlet when the valve piston is in a first position and the inlet does not communicate with the outlet when the valve piston is in a second position. A diaphragm spring is disposed between the latching piston and the valve piston. A holding spring is disposed between the valve piston and the valve body. An unlatching mechanism is in communication with the unlatch port of the valve body.

Abstract: A gear selector apparatus for a transmission having a first gear and a second gear selectively engageable to a shaft through a synchronizer. The gear selector apparatus includes a hydraulic actuator, a gear selection fork engaged with the actuator, a guide bar fixed for common movement to the gear selection fork, a detent mechanism disposed in contact with a first edge of the guide bar, a position sensor disposed in contact with a second edge of the guide bar, a first and a second pressure control valve in communication with the hydraulic actuator, a controller in electrical communication with the position sensor and the first and second pressure control valve. The controller includes a control logic sequence.

Abstract: A method of preventing an automatic engine stop includes: determining a pressure difference between an accumulator fill volume and a fluid conduit in selective fluid communication with the accumulator fill volume; determining a change in the accumulator fill volume from the determined pressure difference; adding the change in the accumulator fill volume to a previous estimate of the accumulator fill volume to determine a current estimate of the accumulator fill volume; comparing the current estimate of the accumulator fill volume to a predetermined threshold; and preventing an automatic engine stop if the current estimate of the accumulator fill volume is below the predetermined threshold.

Abstract: A system for absorbing vibration created by operation of an engine of the present invention includes a first plate driven by an engine shaft and a torque transmitting device for transferring torque from the engine shaft to a transmission input shaft. The system includes a first vibration absorber and a second vibration absorber. The first vibration absorber includes at least one selectively moveable mass. The second vibration absorber includes at least one biasing member and generally opposing ends. The first vibration absorber is configured to absorb vibrations created at a first harmonic of the engine and the second vibration absorber is configured to absorb vibrations created at multiple harmonics of the engine.

Abstract: A system and method for controlling automatic stop-start of a motor vehicle is provided. The system and method is configured to disable an automatic stop-start mode of operation based on accumulator pressure conditions.

Abstract: A system and method are provided for controlling an automatic engine stop-start in conjunction with a transmission having one or more latching valves. The system and method is configured to determine whether conditions are met for an autostop, and if so, to latch or unlatch the latching valve(s) by changing clutch pressure.

Abstract: A method of operating a torque converter clutch in an engine start-stop vehicle improves launch after an auto stop event. During the autostop event, hydraulic fluid is supplied to the torque converter clutch operator through one or more solenoid valves by an auxiliary electric pump. When the prime mover is started at the conclusion of the autostop event, the torque converter clutch is thus locked, assuring rapid and sufficient torque transfer through the torque converter to the transmission and improved acceleration during vehicle launch. As the vehicle accelerates, the hydraulic pressure in the clutch operator is reduced and slip through the clutch increased to achieve a smooth launch and return to conventional torque converter operation.

Abstract: A system and method for controlling an accumulator in a transmission of a motor vehicle includes the steps of determining whether the motor vehicle has been turned off, sensing at least one operating condition of the motor vehicle, and comparing the at least one operating condition to a reference condition. If the at least one operating condition of the motor vehicle fulfills the reference condition and if the motor vehicle has been turned off then the accumulator is discharged.

Abstract: A system includes an accumulator control module that selectively releases automatic transmission fluid from an accumulator. The accumulator control module also receives a plurality of measured characteristics of the accumulator. A temperature estimation module estimates a temperature of the automatic transmission fluid within the accumulator based on at least one of the measured characteristics of the accumulator. An engine start-stop module selectively disables automatic start-stop events of an internal combustion engine based on the estimated temperature of the automatic transmission fluid within the accumulator.

Abstract: A system and method for controlling automatic stop-start of a motor vehicle is provided. The system and method is configured to enable an automatic stop-start mode of operation based on vehicle conditions. In addition, the system and method is configured to selectively actuate an accumulator to prime the transmission for a smooth restart.

Abstract: A control system for controlling clutches of a dual clutch transmission includes an internal model based force control algorithm that converts a desired clutch force to a pressure control signal, a pressure control valve that receives the pressure control signal, a hydraulic actuator to which the pressure control valve applies a pressure related to the pressure control signal, and a clutch assembly with a spring lever and a plurality of clutch plates. The hydraulic actuator applies a desired force corresponding to the pressure control signal to a distal end of the spring lever such that the desired force to the distal end of the spring lever imparts an actual clutch force to the clutch plates.

Abstract: A method to control a hydraulically actuated clutch in a transmission of a vehicle includes monitoring a pressure in a hydraulic circuit providing pressurized fluid to the hydraulically actuated clutch with micro-electromechanical pressure sensor, providing a closed-loop feedback control command for a hydraulic control device providing the pressurized fluid to the hydraulic circuit based upon the monitoring pressure, and controlling the control device based upon the closed-loop feedback control command.

Abstract: An assembly includes a valve body having an inlet in selective communication with an outlet and having an unlatch port, a latching piston disposed within the valve body, a balance spring disposed between the latching piston and the valve body, and a valve piston disposed within the valve body. The inlet communicates with the outlet when the valve piston is in a first position and the inlet does not communicate with the outlet when the valve piston is in a second position. A diaphragm spring is disposed between the latching piston and the valve piston. A holding spring is disposed between the valve piston and the valve body. An unlatching mechanism is in communication with the unlatch port of the valve body.

Abstract: A valve assembly includes a valve body having an input in selective communication with an output, a latching piston disposed within the valve body, a balance spring disposed between the latching piston and the valve body, and a valve piston disposed within the valve body. The input communicates with the output when the valve piston is in a first position and the input does not communicate with the output when the valve piston is in a second position. A diaphragm spring is disposed between the latching piston and the valve piston. A holding spring is disposed between the valve piston and the valve body.

Abstract: A hydraulic control system for a vehicle powertrain with an engine capable of being selectively turned on and turned off includes an accumulator, a plurality of fluid passages through which a fluid flows between the accumulator and a transmission associated with the powertrain, and a smart memory alloy (SMA) valve in fluid communication with at least one of the fluid passages. The SMA valve has a transition temperature. When the temperature of the fluid is less than or about equal to the transition temperature, the SMA valve closes, and when the temperature of the fluid exceeds the transition temperature, the SMA valve opens. When the SMA valve is closed, the accumulator cannot be charged with fluid, that is, the accumulator, does not fill with fluid, and when the SMA valve is open, the accumulator charges with fluid passively.

Abstract: A method for controlling actuation of a torque converter clutch includes monitoring a transmission input speed, comparing the monitored transmission input speed to a threshold input speed, and, when the transmission input speed is less than the threshold input speed, controlling an engine speed based upon a desired minimum engine speed. Controlling the engine speed based upon the desired minimum engine speed includes monitoring a minimum engine speed critical parameter, determining the desired minimum engine speed based upon the minimum engine speed critical parameter, comparing the engine speed to the desired minimum engine speed, and controlling actuation of the clutch device based upon a result of the comparing the engine speed to the desired minimum engine speed.

Abstract: A system and method for controlling automatic stop-start of a motor vehicle is provided. The system and method is configured to enable an automatic stop-start mode of operation that minimizes clutch fill during engine restart.

Abstract: A system and method for controlling automatic stop-start of a motor vehicle is provided. The system and method is configured to enable an automatic stop-start mode of operation based on vehicle conditions. In addition, the system and method is configured to selectively actuate an accumulator to prime the transmission for a smooth restart.

Abstract: A clutch latching system is provided for latching and draining a torque transmitting mechanism. The latching clutch control system may include a latching valve, a release valve, and an accumulator. The clutch latching system may include a clutch feed channel configured to provide hydraulic fluid from a pressurized source to a torque transmitting device when the torque transmitting device is engaged and the engine is running. A latching valve connects the clutch feed channel to the torque transmitting device. The latching valve is configured to selectively trap pressurized hydraulic fluid within the torque transmitting device. A hydraulic pressure storage circuit configured to selectively provide pressurized hydraulic fluid to the latching valve to unlatch the latching valve. A multiple speed transmission is also provided.

Abstract: A system is provided for latching and draining a torque transmitting device. The system may include a clutch feed channel having an inlet portion and a clutch portion. The inlet portion is configured to provide hydraulic fluid from a pressurized source to the clutch portion. The clutch portion is configured to provide hydraulic fluid to a torque transmitting device. An inlet valve connects the inlet portion of the clutch feed channel to the clutch portion of the clutch feed channel. The inlet valve is configured to open to allow the hydraulic fluid to flow from the inlet portion to the clutch portion when the torque transmitting device is engaged. The inlet valve is configured to close and to trap hydraulic fluid within the torque transmitting device when the torque transmitting device is not actively pressurized. A multispeed transmission is also provided.