Abstract:
A hydraulic control system for a transmission includes a source of pressurized hydraulic fluid, a park servo connected to a park mechanism, the park servo having a park side, an out-of-park side, and a biasing member disposed on the park side. A first valve assembly includes a first inlet port in fluid communication with the source of pressurized hydraulic fluid, a first outlet port, and a first valve for selectively allowing fluid communication between the first inlet port and the first outlet port. A second valve assembly includes a second inlet port in direct fluid communication downstream of the first valve assembly, a second outlet port in direct fluid communication with the out-of-park side of the park servo, and a second valve moveable between an out-of-park position and a park position.
Abstract:
A hydraulic control system for a transmission includes a source of pressurized hydraulic fluid, a park servo connected to a park mechanism, the park servo having a park side, an out-of-park side, and a biasing member disposed on the park side. A first valve assembly includes a first inlet port in fluid communication with the source of pressurized hydraulic fluid, a first outlet port, and a first valve for selectively allowing fluid communication between the first inlet port and the first outlet port. A second valve assembly includes a second inlet port in direct fluid communication downstream of the first valve assembly, a second outlet port in direct fluid communication with the out-of-park side of the park servo, and a second valve moveable between an out-of-park position and a park position.
Abstract:
A vehicle includes a transmission, an electrically-driven fluid pump which supplies pressure to a hydraulically-actuated clutch of the transmission, and pump motor sensors positioned with respect to a pump motor of the fluid pump. The sensors are configured to measure electrical properties of the pump motor, and to output the measured electrical properties as input signals. A controller detects when the hydraulic circuit is fully charged by determining an actual speed of the pump motor. The controller calculates an average pump torque and a slope of the average pump torque for the pump motor using the input signals. A flag is set via the controller indicating that a calibrated line pressure has been attained in the hydraulic circuit when the slope of the average pump torque reaches zero and the speed of the pump motor reaches a calibrated speed.
Abstract:
A hydraulic control system for a multiple mode electro-mechanical drive unit of a motor vehicle includes multiple torque transmitting mechanisms each including at least one friction clutch. Multiple clutch control valves are individually in fluid communication with one of the torque transmitting mechanisms and are operable when actuated to change a condition of the torque transmitting mechanisms from a clutch disconnected condition to a clutch engaged condition. Solenoid valves are individually paired with and in fluid communication with one of the clutch control valves. A normally open variable force solenoid valve is in fluid communication with the solenoid valves. Operation of the variable force solenoid valve sets a hydraulic pressure between any of the solenoid valves in an open condition and its paired clutch control valve.
Abstract:
A hydraulic control system for a multiple mode electro-mechanical drive unit of a motor vehicle includes multiple torque transmitting mechanisms each including at least one friction clutch. Multiple clutch control valves are individually in fluid communication with one of the torque transmitting mechanisms and are operable when actuated to change a condition of the torque transmitting mechanisms from a clutch disconnected condition to a clutch engaged condition. Solenoid valves are individually paired with and in fluid communication with one of the clutch control valves. A normally open variable force solenoid valve is in fluid communication with the solenoid valves. Operation of the variable force solenoid valve sets a hydraulic pressure between any of the solenoid valves in an open condition and its paired clutch control valve.
Abstract:
A vehicle includes a transmission, an electrically-driven fluid pump which supplies pressure to a hydraulically-actuated clutch of the transmission, and pump motor sensors positioned with respect to a pump motor of the fluid pump. The sensors are configured to measure electrical properties of the pump motor, and to output the measured electrical properties as input signals. A controller detects when the hydraulic circuit is fully charged by determining an actual speed of the pump motor. The controller calculates an average pump torque and a slope of the average pump torque for the pump motor using the input signals. A flag is set via the controller indicating that a calibrated line pressure has been attained in the hydraulic circuit when the slope of the average pump torque reaches zero and the speed of the pump motor reaches a calibrated speed.