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 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 powertrain system includes a transmission employing an electrically-powered hydraulic pump providing pressurized hydraulic fluid to a hydraulic circuit. A method of operating the powertrain system includes monitoring a temperature of the hydraulic pump. In response to the temperature exceeding a threshold temperature, power output from an electrically-powered motor coupled to the hydraulic pump is derated, which includes decreasing rotational speed of the hydraulic pump and maintaining hydraulic pressure in the hydraulic circuit.

Abstract: A powertrain system includes a transmission employing an electrically-powered hydraulic pump providing pressurized hydraulic fluid to a hydraulic circuit. A method of operating the powertrain system includes monitoring a temperature of the hydraulic pump. In response to the temperature exceeding a threshold temperature, power output from an electrically-powered motor coupled to the hydraulic pump is derated, which includes decreasing rotational speed of the hydraulic pump and maintaining hydraulic pressure in the hydraulic circuit.

Abstract: A transmission fluid pump control system of a vehicle includes a target speed module and a speed control module. The target speed module determines a target speed of an electric transmission fluid pump based on a target output flowrate of the electric transmission fluid pump, a predetermined maximum allowable amount of leakage of transmission fluid pumps, and an efficiency of the electric transmission fluid pump. The speed control module applies power to the electric transmission fluid pump based on the target speed.

Abstract: A transmission system of a vehicle comprises a pump, an auxiliary pump, and a transmission. The pump pressurizes transmission oil when an engine is operating. The auxiliary pump operably coupled to the pump and located parallel to the pump that pressurizes the transmission oil when the engine is not operating. The transmission selects a gear ratio based on the pressurized transmission oil.

Abstract: A hybrid transmission is provided, including a transmission housing with an input cover attached to a main housing portion, and a hydraulic fluid reservoir in fluid communication with and attached to the transmission housing. The transmission also includes an input shaft in driving communication with an engine. A pump cover is attached to the input housing to define a pump pocket therebetween. A torque transmitting assembly is secured to the pump cover. The torque transmitting assembly includes a piston housing member that is coaxial with and longitudinally spaced from the pump cover to define an inlet passage therebetween. The inlet passage is configured to communicate the hydraulic fluid reservoir with the transmission housing, and is oriented at least partially radially adjacent to the pump pocket. A gasket member is disposed between the pump cover and piston housing member, and configured for fluidly sealing the same.

Abstract: A pump for a hybrid transmission includes an input shaft having a mating surface—which may include a flat portion—on an outer surface thereof, and a pump rotor coaxial with the input shaft. The pump rotor has an inner surface corresponding to the mating surface of the input shaft, and is directly and drivingly coupled to the input shaft for common rotation therewith. The hybrid transmission may further include an input housing and pump housing, and a pump pocket—in which the pump rotor operates—defined by the input housing, pump housing, and input shaft. The pump is configured to be testable prior to mating the hybrid transmission to an engine. The pump rotor is bounded axially by the input shaft, and a pump guide is configured to center the pump rotor, and to be installed prior to installation of the pump rotor.

Abstract: A hydraulic control system for distributing pressurized fluid to a multi-mode hybrid-type power transmission is provided, as well as a method for regulating the same. The hydraulic control system includes an engine-driven main pump in fluid communication with a main regulator valve, and an electrically-driven auxiliary pump in fluid communication with an auxiliary regulator valve. One pressure control solenoid provides feedback (boost) pressure to both regulator valves, and thereby modify output of the main and auxiliary pumps. A controller selectively modifies distribution of boost pressure to ensure a continuous and controllable feed of hydraulic pressure to the transmission during all vehicle operations.

Abstract: A method for controlling a hydraulic flow within a powertrain comprising an electromechanical transmission mechanically-operatively coupled to an engine adapted to selectively transmit power to an output, wherein the transmission utilizes a hydraulic control system serving a number of hydraulic oil consuming functions includes monitoring minimum hydraulic pressure requirements for each of the functions, determining a requested hydraulic pressure based upon the monitoring minimum hydraulic pressure requirements and physical limits of the hydraulic control system including a maximum pressure, determining a desired flow utilizing a hydraulic control system flow model based upon the requested hydraulic pressure, and utilizing the desired flow to control an auxiliary hydraulic pump.

Abstract: A method of operating an auxiliary pump for an electrically variable transmission includes purging the auxiliary pump when an auxiliary pump temperature is below a minimum operating temperature and above a minimum purge temperature. The auxiliary pump fluid temperature and the minimum purge temperature are determined based upon the transmission fluid temperature and the ambient temperature.

Abstract: A cooling system for an electrically variable transmission includes an electric motor having a plurality of connectors. The plurality of connectors are each assembled within a plurality of connector openings in a terminal block. Fluid from within a passageway is supplied by a pressurized fluid source, and an orifice for the passageway is located adjacent to one of the plurality of connector opening. The fluid flowing from the passageway is directed onto one of the plurality of connectors.

Abstract: A method of pressure control for transmissions having a hydraulic circuit selectively communicating with first and second pumps via first and second regulators includes commanding communication to the hydraulic circuit to transition from the first to the second pump and the PCS to set the regulators to a high pressure-regulation level. The hydraulic circuit line pressure is raised to an elevated value exceeding a target value. The line pressure is lowered from the elevated to the target value at or after completing the transition to the second pump. The method may include transitioning communication with the hydraulic circuit from the second to the first pump. The PCS maintains the regulators at the high level and line pressure is raised to the elevated value. PCS sets the regulators to a low level, and line pressure returns to the target only at or after completing the transition to the first pump.

Abstract: A hydraulic control system for a multi-mode hybrid-type power transmission is provided, including an engine-driven main pump in fluid communication with a main regulator valve, and an electrically driven auxiliary pump in fluid communication with an auxiliary regulator valve. A first pressure control solenoid is configured to provide boost pressure to the main regulator valve and thereby boost output of the main pump. A second pressure control solenoid is configured to provide boost pressure to the auxiliary regulator valve and thereby boost output of the auxiliary pump. The distribution of boost pressure from the pressure control solenoids is selectively modified such that at least one of the flows of pressurized fluid from the pumps is equal to the current line pressure requirements of the transmission during engine auto-start and auto-stop, and transitions thereto. An improved method for regulating the hydraulic control system is also provided.

Abstract: A method of operating an auxiliary pump for an electrically variable transmission includes purging the auxiliary pump when an auxiliary pump temperature is below a minimum operating temperature and above a minimum purge temperature. The auxiliary pump fluid temperature and the minimum purge temperature are determined based upon the transmission fluid temperature and the ambient temperature.

Abstract: A cooling system for an electrically variable transmission includes an electric motor having a plurality of connectors. The plurality of connectors are each assembled within a plurality of connector openings in a terminal block. Fluid from within a passageway is supplied by a pressurized fluid source, and an orifice for the passageway is located adjacent to one of the plurality of connector opening. The fluid flowing from the passageway is directed onto one of the plurality of connectors.

Abstract: A method of pressure control for transmissions having a hydraulic circuit selectively communicating with first and second pumps via first and second regulators includes commanding communication to the hydraulic circuit to transition from the first to the second pump and the PCS to set the regulators to a high pressure-regulation level. The hydraulic circuit line pressure is raised to an elevated value exceeding a target value. The line pressure is lowered from the elevated to the target value at or after completing the transition to the second pump. The method may include transitioning communication with the hydraulic circuit from the second to the first pump. The PCS maintains the regulators at the high level and line pressure is raised to the elevated value. PCS sets the regulators to a low level, and line pressure returns to the target only at or after completing the transition to the first pump.

Abstract: A transmission system of a vehicle comprises a pump, an auxiliary pump, and a transmission. The pump pressurizes transmission oil when an engine is operating. The auxiliary pump operably coupled to the pump and located parallel to the pump that pressurizes the transmission oil when the engine is not operating. The transmission selects a gear ratio based on the pressurized transmission oil.

Abstract: A hybrid transmission is provided, including a transmission housing with an input cover attached to a main housing portion, and a hydraulic fluid reservoir in fluid communication with and attached to the transmission housing. The transmission also includes an input shaft in driving communication with an engine. A pump cover is attached to the input housing to define a pump pocket therebetween. A torque transmitting assembly is secured to the pump cover. The torque transmitting assembly includes a piston housing member that is coaxial with and longitudinally spaced from the pump cover to define an inlet passage therebetween. The inlet passage is configured to communicate the hydraulic fluid reservoir with the transmission housing, and is oriented at least partially radially adjacent to the pump pocket. A gasket member is disposed between the pump cover and piston housing member, and configured for fluidly sealing the same.

Abstract: A pump for a hybrid transmission includes an input shaft having a mating surface—which may include a flat portion—on an outer surface thereof, and a pump rotor coaxial with the input shaft. The pump rotor has an inner surface corresponding to the mating surface of the input shaft, and is directly and drivingly coupled to the input shaft for common rotation therewith. The hybrid transmission may further include an input housing and pump housing, and a pump pocket—in which the pump rotor operates—defined by the input housing, pump housing, and input shaft. The pump is configured to be testable prior to mating the hybrid transmission to an engine. The pump rotor is bounded axially by the input shaft, and a pump guide is configured to center the pump rotor, and to be installed prior to installation of the pump rotor.