Electro-hydraulic failure recovery control for dual clutch transmission
AssigneeAllison Transmission, Inc.
InventorBryan Hagelskamp
Life of this patent
Estimating the term…
Abstract
A control for a multi-speed automatic vehicle transmission includes electrical and hydraulic components, such as pressure control valve systems in fluid communication with shift valves and electrohydraulic actuators. The control includes electrohydraulic features configured to enable the transmission to respond to an electrical failure whether the transmission is in neutral, a reverse range, or one of a plurality of forward ranges.
Claims20
An electro-hydraulic control for an automatic dual-clutch transmission, comprising
- a plurality of shift valves, each shift valve being configured to control engagement of a torque transmitting mechanism of the transmission to enable the transmission to selectively attain a plurality of forward ranges and at least one reverse range,
- a plurality of trim valves, each trim valve being in direct fluid communication with at least one of the shift valves, and
- a normally-high actuator operably coupled to each of the trim valves,
- wherein the number of shift valves equals the number of trim valves and the number of normally-high actuators equals the number of trim valves.
An electrohydraulic control for a multi-speed automatic transmission, comprising
- a first plurality of trim valves each operably coupled to a normally-low actuator and each being in direct fluid communication with a fluid chamber of a torque transmitting mechanism of the transmission,
- a second plurality of trim valves each operably coupled to a normally-high actuator,
- a plurality of shift valves each being in fluid communication with one of the second plurality of trim valves and each being in direct fluid communication with a torque transmitting mechanism of the transmission, and
- at least one valve operable to control at least one shift fork of the transmission.
A transmission failure recovery control for a dual clutch transmission, comprising
- first electrohydraulic means for recovering from an electrical failure by causing the dual clutch transmission to attain a first failure recovery range if the dual clutch transmission is in a first reverse range or a neutral range when the failure occurs,
- second electrohydraulic means for recovering from an electrical failure by causing the dual clutch transmission to attain a second failure recovery range if the dual clutch transmission is in a second reverse range when the failure occurs,
- third electrohydraulic means for recovering from an electrical failure by causing the dual clutch transmission to attain a second failure recovery range if the dual clutch transmission is in a low forward range when the failure occurs, and
- fourth electrohydraulic means for recovering from an electrical failure by causing the dual clutch transmission to attain a third failure recovery range if the dual clutch transmission is in a high forward range when the failure occurs.
Dependencies are inferred from the claim text.