Abstract: A method of regulating displacement in a displacement on demand engine includes determining a desired engine displacement and determining a current engine displacement. The method further includes adjusting activation of a first cylinder to partially achieve the desired engine displacement and subsequently adjusting activation of a second cylinder to fully achieve the desired engine displacement from the current engine displacement. The method adjusts activation of the cylinders one at a time to reduce vibration in the engine.

Abstract: A differential lubrication system includes structure forming a torque converter feed passage in fluid communication with a fluid source and in which fluid is selectively supplied to a torque converter. Structure forming a branch passage for lubricating a differential mechanism extends from the torque converter feed passage to divert fluid to the differential mechanism prior to the fluid being supplied to the torque converter. Two flow restrictions and a valve mechanism may be employed to control lubrication of the differential mechanism. One of the flow restrictions may form a nozzle so that fluid is sprayed onto the differential mechanism. A method of lubricating the differential mechanism is also provided.

Abstract: An engine control system that monitors flow restriction through an exhaust gas recirculation (EGR) system of an engine includes a first module that calculates a test EGR mass flow rate based on a first average EGR mass flow rate when the EGR system is in an EGR OFF mode and a second average EGR mass flow rate when the EGR system is in an EGR ON mode. A second module selectively generates a fault signal based on the test EGR mass flow rate.

Abstract: The present invention relates to a torsional damper for an electrically-variable transmission. The torsional damper is equipped with a lock-out clutch to directly couple the engine to the input shaft of the transmission. The electric motors provided with the electrically-variable transmission can serve to effectively cancel out engine compression pulses when the springs of the torsional damper are locked out. The present invention also includes damper springs of variable rates to effectively attenuate distinctive or inconsistent torque fluctuations when the engine is operating in displacement-on-demand mode.

Abstract: An engine active motion control system for controlling engine dynamic torque includes an engine that generates a first dynamic torque. A first module selectively initiates generation of a second dynamic torque about an axis of rotation of a crankshaft of the engine in a direction opposite that of the first dynamic torque generated through the crankshaft.

Abstract: Methods and apparatus are provided which generate an error signal if a sensor is either anticipated to fail or fails. At least two sensors provide input signals having magnitudes that approximately correspond to a sensed event. A processor calculates an actual correlation error for the two signals. A processor then further calculates an estimated new correlation value based on the difference of a stored initial correlation value and the actual correlation error. After a predetermined number of estimated correlation values are calculated, the error signal is generated if the difference between an estimated correlation value and the actual correlation error exceeds a predetermined threshold.

Abstract: A detection circuit detects a difference between a source current and a return current. The detection circuit includes a constantly biased magnetic core through which conductors of the source and return currents extend, and a sense winding around the core. The sense winding carries an AC signal. A sensing circuit connected with the sense winding senses a change in small signal impedance of the sense winding relative to the core. This detection circuit can be used to protect people and equipment against accidental contact with high-voltage DC systems.

Abstract: A knock detection system for a spark-ignition engine includes a knock sensor that is responsive to vibration of the engine and that generates a knock signal. A first module calculates a knock energy based on the knock signal and a second module calculates a knock intensity based on the knock energy. A third module regulates a spark timing of the engine based on the knock intensity.

Abstract: The present invention relates to a torsional damper for an electrically variable transmission. The torsional damper is equipped with a hydraulically actuable lock-out clutch to selectively directly couple the engine to the input shaft of the transmission. The electric motors provided with the electrically variable transmission can serve to effectively cancel out engine compression pulses when the springs of the torsional damper are locked out. During higher speeds the centrifugal loading placed on oil in the torsional damper increases, which may cause the lock-out clutch to inappropriately engage. The present invention hydraulically balances the hydraulic actuator (or piston) driving the lock-out clutch to appropriately regulate lock-out clutch engagement.

Abstract: A powertrain braking system for a vehicle includes an powerplant that can be regulated to provide a desired powerplant torque and a transmission that transfers the desired powerplant torque at one of a plurality of gear ratios to provide a desired axle torque. A control module calculates an axle torque command based on a powertrain braking request and determines a shift command based on the powertrain braking request. The control module controls the powerplant based on the axle torque command and the transmission based on the shift command to achieve a desired vehicle deceleration rate that corresponds with the powertrain braking request.

Abstract: A cast oil pan is connected between en engine crankcase and a lower end portion of a transmission bellhousing. Oil pan side walls each incorporate an integrally cast truss extending between an end flange of the oil pan and adjacent portions of an upper flange to stiffen the connection of the engine crankcase with the transmission bellhousing. Each truss includes a horizontal rail, a plurality of bolt columns extending between the horizontal rail and the upper flange adjacent corresponding bolt openings. Diagonal ribs extend from the oil pan flange generally toward the peripheral end flange. Oil pan bolts at the truss locations pass through the horizontal rail and the oil pan upper flange adjacent the bolt columns so that bolt clamping forces are carried through the bolt columns. The heads of the bolts are positioned below the horizontal rail accessible by power tools for securing and removing the bolts.

Abstract: The present invention relates to the use of a magnetic sensor to detect the speed of transmission clutch plates or clutch hub. A clutch fiber plate, which is mechanically linked to a buried (or inwardly nested) transmission component, is serrated to generate detectable pulsations or fluctuations in the magnetic intensity of the clutch fiber plate as it rotates. The speed of the buried transmission component is useful in controlling a second clutch arrangement to reduce engine torsional pulses by generating a predetermined amount of slip upon engagement. Moreover, the sensor is configurable to determine the acceleration of the clutch fiber plate to control engine acceleration during a vehicle launch. The sensor is mounted to the transmission housing radially superjacent the clutch fiber plate; therefore, the axial space claim for the transmission does need not increase to accommodate the sensor.

Abstract: The present invention provides an electrically variable transmission having two motor/generators, two differential gear sets such as planetary gear sets, and five torque transfer devices arranged to provide improved launch, performance and gradeability, and enabling five fixed speed ratios. An input member is continuously connected to one member (preferably a ring gear) of the first planetary gear set, and an output member is continuously connected to one member (preferably a carrier) of the second planetary gear set. One motor/generator is continuously connected to another member (preferably a sun gear) in the first planetary gear set as well as being selectively connected to a member (preferably a ring gear) of the second planetary gear set. The second motor/generator is continuously connected to the remaining member (preferably a sun gear) of the second planetary gear set, and is selectively connected to the remaining member (preferably a carrier) of the first planetary gear set.

Abstract: An electrically variable transmission includes: an input member to receive power from an engine; an output member; first and second motor/generators; and first and second differentially geared planetary gear sets each having first, second and third gear members. The input member is continuously connected to the first member of the first planetary gear set, and the output member is continuously connected to the first member of the second planetary gear set. The first motor/generator is continuously connected to the second member of the first planetary gear set, and selectively connected to the second member of the second planetary gear set. The second motor/generator is continuously connected with the third member of the second planetary gear set. Five or six torque transfer devices selectively connect members of the planetary gear sets with each other or with ground. The torque transfer devices are engageable in combinations of two or three to provide five or six available fixed speed ratios.

Abstract: A method for providing traction control in vehicle powertrain systems is particularly adapted for traction control in a powertrain system of a hybrid electric vehicle comprising an internal combustion engine, an electric machine and a transmission that is operatively coupled to the electric machine and the engine and adapted to provide a transmission torque output in response to a transmission torque input received as a torque output from either or both of the engine and the electric machine. The method is adapted to utilize conventional traction control and engine control hardware, software and communication standards to implement traction control. In one embodiment of the invention, a conventional traction controller is used to detect a wheel spin condition and provide a plurality of first output torque command messages in response thereto.

Abstract: An electrically variable transmission is provided including an input member to receive power from an engine; an output member connected to a transfer gear; first and second motor/generators; and first and second simple planetary gear sets each having first, second and third members. The input member is continuously connected to the first member of the first gear set, and the output member is continuously connected to the first member of the second gear set. The first motor/generator is continuously connected to the second member of the first gear set. The second motor/generator is continuously connected with the third member of the first or second gear set. The transfer gear and first and second torque transfer devices are positioned between the first and second gear sets.

Abstract: A narrow test chamber has at least one heater immersed with its major faces parallel to the fuel surface, part way up the chamber. Heater resistance increases non-linearly as a critical temperature is reached. When the heater is energized, fuel begins to evaporate. Heater temperature remains below the critical temperature until the fuel level drops to or just below the heater level, whereupon heater temperature rises quickly to the critical temperature and heater current drops sharply. The time t1 required to reach this point and the heater current or energy consumed vary according to the fuel distillation Drivability Index (DI). The DI is determined from the measured heater current and t1 or from differential measurement of t1 for two heaters mounted one above the other, by calculation or from a look-up table. The DI value is then used to control engine operation to reduce pollution and improve performance.

Abstract: A hybrid vehicle includes an engine having at least one cylinder and an electric machine that drives the engine during a start-up period. A control module monitors a rotational speed of the engine and regulates torque generated by the electric machine based on the rotational speed during the start-up period and a maximum discharge power available to power the electric machine.

Abstract: A method for providing an active engine stop of the engine of a hybrid electric vehicle. The method utilizes the electric machine to oppose and rapidly stop the rotation of the engine at a controlled rate. The method includes the calculation of an input speed reduction trajectory using the engine speed when the active engine stop request is made and a predetermined speed reduction interval. The speed reduction interval is less than a time from the active stop request to the shutoff command to the electric machine The method provides rapid deceleration of the engine, particularly through the powertrain resonance speed, reducing the amount of vibration energy dissipated through the powertrain and chassis. The method removes the electric machine torques from the engine prior to achieving zero engine speed in order to avoid imparting a negative engine speed or counter-rotation of the engine.

Abstract: An electrically variable transmission includes a power source, three differential gear sets, first and second motor/generators each connected to at least one of the gear sets, and torque-transmitting mechanisms. An input member transfers power from the power source through the differential gear sets to an output member. The torque-transmitting mechanisms are selectively engageable to provide an input-split first electrically variable mode having equal forward and reverse speed ratios for given input speeds and a compound, power-split second electrically variable mode. Torque provided from the power source is added to torque provided from the second motor generator in both forward and reverse electrically variable modes.