Abstract: The present invention provides a method of operating an electro-hydraulic control system for a dual clutch transmission having seven forward speeds or gear ratios and reverse. The control system includes an oil delivery subsystem, a clutch control subsystem and a synchronizer control subsystem. All three subsystems are under the control of a transmission control module. The method of operation includes gathering data from various shaft speed, clutch position and shift actuator position sensors and utilizing pressure control (PCS) and flow control (FCS) solenoid valves and a logic valve to pre-stage and engage (and disengage) hydraulic shift actuators associated with a requested and current gear and to sequentially engage one of a pair of input clutches.

Abstract: A hydraulic control system and method for controlling a dual clutch transmission includes a plurality of pressure and flow control devices and logic valve assemblies in fluid communication with a plurality of clutch actuators and with a plurality of synchronizer actuators. The clutch actuators are operable to actuate a plurality of torque transmitting devices and the synchronizer actuators are operable to actuate a plurality of synchronizer assemblies. Selective activation of combinations of the pressure control solenoids and the flow control solenoids allows for a pressurized fluid to activate at least one of the clutch actuators and synchronizer actuators in order to shift the transmission into a desired gear ratio.

Abstract: A method of adjusting a pressure signal to an actuator piston to control movement of a synchronizer actuator fork of a transmission includes moving the synchronizer actuator fork from a start position into a target position by applying an initial fluid pressure value. The time required to move the synchronizer actuator fork is measured to define a measured actuation time, and compared to a target actuation time. A correction factor is applied to the initial fluid pressure value to define a revised fluid pressure value when the measured actuation time is not within a pre-defined time range of the target actuation time. When the measured actuation time is greater than the pre-defined time range of the target actuation time, the initial fluid pressure value is increased. When the measured actuation time is less than the pre-defined time range of the target actuation time, the initial fluid pressure value is decreased.

Abstract: A clutch control system for a vehicle includes a shift command module and an offgoing clutch control module. The shift command module commands an upshift of a clutch-to-clutch transmission when an engine torque is less than a predetermined negative torque. The offgoing clutch control module increases an offgoing clutch pressure above a predetermined apply pressure in response to the command. An offgoing clutch is fully engaged when the offgoing clutch pressure is greater than the predetermined apply pressure.

Abstract: A control system includes a pressure control solenoid and a flow control solenoid having an input in fluid communication with the pressure control solenoid. A piston adjusts a position of a shift fork and includes a first area in fluid communication with the pressure control solenoid and a second area in fluid communication with the flow control solenoid. A fork sensor senses a position of a shift fork. A flow determining module determines a fork velocity for the shift fork, adjusts the fork velocity to generate an adjusted fork velocity based on the position, and generates a flow command for the flow control solenoid based on the adjusted fork velocity. A pressure determining module generates a pressure command for the pressure control solenoid. The shift fork is at least one of moved from a sync position to an engaged position and from an engaged position to a neutral position.

Abstract: A control system includes a pressure control solenoid and a flow control solenoid having an input in fluid communication with the pressure control solenoid. A piston adjusts a position of a shift fork and includes a first area in fluid communication with the pressure control solenoid and a second area in fluid communication with the flow control solenoid. A fork sensor senses a position of a shift fork. A slip sensing module estimates slip acceleration between an input shaft and a gear. A flow determining module generates a flow command for the flow control solenoid. A sync control module determines a slip acceleration profile including an estimated slip acceleration, adjusts the estimated slip acceleration based on the measured slip acceleration, and generates a pressure command for the pressure control solenoid based on the adjusted slip acceleration.

Abstract: A hydraulic control system for a dual clutch transmission includes a plurality of pressure and flow control devices and logic valve assemblies in fluid communication with a plurality of clutch actuators and with a plurality of synchronizer actuators. The clutch actuators are operable to actuate a plurality of torque transmitting devices and the synchronizer actuators are operable to actuate a plurality of synchronizer assemblies. Selective activation of combinations of the pressure control solenoids and the flow control solenoids allows for a pressurized fluid to activate at least one of the clutch actuators and synchronizer actuators in order to shift the transmission into a desired gear ratio.

Abstract: A hydraulic control system and method for controlling a dual clutch transmission includes a plurality of pressure and flow control devices and logic valve assemblies in fluid communication with a plurality of clutch actuators and with a plurality of synchronizer actuators. The clutch actuators are operable to actuate a plurality of torque transmitting devices and the synchronizer actuators are operable to actuate a plurality of synchronizer assemblies. Selective activation of combinations of the pressure control solenoids and the flow control solenoids allows for a pressurized fluid to activate at least one of the clutch actuators and synchronizer actuators in order to shift the transmission into a desired gear ratio.

Abstract: A hydraulic control system and method for controlling a dual clutch transmission includes a plurality of pressure and flow control devices and logic valve assemblies in fluid communication with a plurality of clutch actuators and with a plurality of synchronizer actuators. The clutch actuators are operable to actuate a plurality of torque transmitting devices and the synchronizer actuators are operable to actuate a plurality of synchronizer assemblies. Selective activation of combinations of the pressure control solenoids and the flow control solenoids allows for a pressurized fluid to activate at least one of the clutch actuators and synchronizer actuators in order to shift the transmission into a desired gear ratio.

Abstract: The present invention provides a method of operating an electro-hydraulic control system for a dual clutch transmission having seven forward speeds or gear ratios and reverse. The control system includes an oil delivery subsystem, a clutch control subsystem and a synchronizer control subsystem. All three subsystems are under the control of a transmission control module. The method of operation includes gathering data from various shaft speed, clutch position and shift actuator position sensors and utilizing pressure control (PCS) and flow control (FCS) solenoid valves and a logic valve to pre-stage and engage (and disengage) hydraulic shift actuators associated with a requested and current gear and to sequentially engage one of a pair of input clutches.

Abstract: A method of controlling a hydraulic control system for a dual clutch transmission includes controlling a plurality of pressure and flow control devices in fluid communication with a plurality of clutch actuators and with a plurality of synchronizer actuators. The clutch actuators are operable to actuate a plurality of torque transmitting devices and the synchronizer actuators are operable to actuate a plurality of synchronizer assemblies. Selective activation of combinations of the pressure control solenoids and the flow control solenoids allows for a pressurized fluid to activate at least one of the clutch actuators and synchronizer actuators in order to shift the transmission into a desired gear ratio.

Abstract: A method of controlling a hydraulic control system for a dual clutch transmission includes controlling a plurality of pressure and flow control devices in fluid communication with a plurality of clutch actuators and with a plurality of synchronizer actuators. The clutch actuators are operable to actuate a plurality of torque transmitting devices and the synchronizer actuators are operable to actuate a plurality of synchronizer assemblies. Selective activation of combinations of the pressure control solenoids and the flow control solenoids allows for a pressurized fluid to activate at least one of the clutch actuators and synchronizer actuators in order to shift the transmission into a desired gear ratio.

Abstract: A clutch control system for a vehicle includes a shift command module and an offgoing clutch control module. The shift command module commands an upshift of a clutch-to-clutch transmission when an engine torque is less than a predetermined negative torque. The offgoing clutch control module increases an offgoing clutch pressure above a predetermined apply pressure in response to the command. An offgoing clutch is fully engaged when the offgoing clutch pressure is greater than the predetermined apply pressure.

Abstract: A dual clutch transmission (DCT) control module includes a position control module that actuates a shift fork of the DCT during a first shift state based on a measured shift fork position and a target shift fork position. A force control module adjusts a control force associated with the shift fork during a second shift state based on synchronizer slip.

Abstract: A control system includes a pressure control solenoid and a flow control solenoid having an input in fluid communication with the pressure control solenoid. A piston adjusts a position of a shift fork and includes a first area in fluid communication with the pressure control solenoid and a second area in fluid communication with the flow control solenoid. A fork sensor senses a position of a shift fork. A slip sensing module estimates slip acceleration between an input shaft and a gear. A flow determining module generates a flow command for the flow control solenoid. A sync control module determines a slip acceleration profile including an estimated slip acceleration, adjusts the estimated slip acceleration based on the measured slip acceleration, and generates a pressure command for the pressure control solenoid based on the adjusted slip acceleration.

Abstract: A control system includes a pressure control solenoid and a flow control solenoid having an input in fluid communication with the pressure control solenoid. A piston adjusts a position of a shift fork and includes a first area in fluid communication with the pressure control solenoid and a second area in fluid communication with the flow control solenoid. A fork sensor senses a position of a shift fork. A flow determining module determines a fork velocity for the shift fork, adjusts the fork velocity to generate an adjusted fork velocity based on the position, and generates a flow command for the flow control solenoid based on the adjusted fork velocity. A pressure determining module generates a pressure command for the pressure control solenoid. The shift fork is at least one of moved from a sync position to an engaged position and from an engaged position to a neutral position.