Twin clutch automated transmission

A twin-clutch transmission for use in a motor vehicle having an engine and a driveline, comprising:

• an output shaft adapted for connection to the driveline;
• first input shaft driving a first countershaft;
• a second input shaft driving a second countershaft;
• a first engine clutch operable for establishing a releasable drive connection between the engine and said first input shaft;
• a second engine clutch operable for establishing a releasable drive connection between the engine and said second input shaft;
• a geartrain including first and third drive gears fixed to said first countershaft;
• second and fourth drive gears fixed to said second countershaft, a first speed gear supported on said output shaft and meshed with said first drive gear, a second speed gear supported on said output shaft and meshed with said third drive gear, and a fourth speed gear supported on said output shaft and meshed with said fourth drive gear;
• a first shift clutch operable for releasable coupling said first and third speed gears to said output shaft;
• a second shift clutch operable for releasably coupling said second and fourth speed gears to said output shaft;
• a first fluid pump driven by said first input shaft;
• a second fluid pump driven by said second input shaft;
• a control valve permitting fluid flow between said first and second fluid pumps, and
• a transmission control system for controlling coordinated actuation of said first and second engine clutches to cause powershift sequential gear shifts, such that when one of said first and second input shafts is released from driven connection with the engine, said fluid pump associated with the driven one of said first and second input shafts supplies high pressure fluid through said control valve to said fluid pump associated with the released one of said first and second input shafts to synchronize the rotary speed of the released one of said first and second input shafts to said output shaft.

An automated twin-clutch transmission adapted to transfer power from the engine to a driveline of a motor vehicle, comprising;

• a first engine clutch operable to establish a releasable drive connection between the engine and a first input shaft;
• a second engine clutch operable to establish a releasable drive connection between the engine and a second input shaft;
• an output shaft adapted to transfer power to the driveline;
• a first countershaft driven by said first input shaft;
• a second countershaft driven by said second input shaft;
• first and second constant-mesh gearsets interconnecting said first and second countershafts to said output shaft;
• first and second power-operated dog clutches for selectively engaging said first and second gearsets;
• a transmission controller for controlling coordinated actuation of said first and second engine clutches and said first and second dog clutches;
• and
• a clutch control system including a first fluid pump driven by said first input shaft for delivering high pressure fluid to a first control valve for selectively releasing said first engine clutch, a second fluid pump driven by said second input shaft for delivering high pressure fluid to a second control valve for selectively releasing said second engine clutch, and flow control valving for controlling fluid flow between said first and second fluid pumps in response to release of the drive connection between one of said first and second input shafts and the engine.