Patent application number | Description | Published |
20100170740 | METHOD AND APPARATUS FOR ADAPTING MINIMUM TORQUE CONVERTER SLIP FOR NEUTRAL IDLE CONTROL - A method adaptively learns torque converter (TC) slip in a transmission having a hydrodynamic torque converter assembly by setting a baseline TC slip profile, determining an actual TC slip value at different temperatures, generating an adapted TC slip profile by adapting the baseline TC slip profile in response to the actual TC slip values, and controlling the amount of TC slip during a neutral idle (NI) state of the transmission using the adapted TC slip profile. A vehicle includes a torque converter and a controller. The controller calibrates the TC slip during a first transmission state, and controls the amount of TC slip during a second transmission state. The controller measures actual TC slip data points, and adapts a TC slip profile to more closely approximate a natural slip curve of the vehicle in response to the actual slip TC slip value data points. | 07-08-2010 |
20100304928 | METHOD AND APPARATUS FOR DIRECTLY ENTERING NEUTRAL IDLE DURING A GARAGE SHIFT - A vehicle includes an engine, a multi-speed transmission with a neutral idle (NI) mode capability, and a controller. The controller allows direct entry into the NI mode during a garage shift (GS) event. One clutch is actuated during the GS event, and a different clutch is actuated to directly enter NI mode after completing the GS event. A method allows for direct entry into a neutral idle (NI) mode during a garage shift (GS) event using a multi-speed transmission. The method includes automatically actuating a first clutch of a plurality of clutches to complete the GS event, and a second clutch of the plurality of clutches to directly enter the NI mode after completing the GS event. The method may include holding the NI clutch at a pre-learned NI pressure during a fill stage of the GS clutch, and varying a turbine pull-down rate to provide different GS shift feels. | 12-02-2010 |
20110040463 | METHOD AND SYSTEM FOR CALIBRATING A PRESSURE SENSOR FOR AN AUTOMATIC TRANSMISSION - A method and control system for operating a transmission includes a transmission control module determining a transmission sensor signal and a transmission pressure sensor offset prior to starting a vehicle engine and an engine start initiator starting the vehicle engine. The transmission control module controls a transmission function in response the transmission pressure sensor offset and the pressure sensor signal. | 02-17-2011 |
20110071741 | METHOD AND APPARATUS FOR ENTERING NEUTRAL IDLE FROM A FORWARD DRIVE MODE - A transmission includes a plurality of clutches that are selectively engageable alone or in combination with each other to establish a plurality of forward drive modes, wherein one of the clutches is configured as a neutral idle (NI) clutch that is selectively actuated to shift the transmission into an NI state, and a controller. The controller is adapted to shift the transmission from a forward drive mode into the NI state during a coast-down maneuver prior to the transmission reaching a zero output speed. A method of shifting the transmission into the NI state includes determining the presence of a predetermined one of the forward drive modes using the controller, and using the controller to actuate a designated one of the clutches as an NI clutch to enter the NI state during the forward drive mode, during a coast-down maneuver, and prior to the transmission reaching a zero output speed. | 03-24-2011 |
20110077830 | METHOD AND APPARATUS FOR NEUTRAL IDLE CLUTCH CONTROL IN A VEHICLE HAVING AN ENGINE START-STOP POWERTRAIN - A method and apparatus provide control of a neutral idle (NI) clutch to allow a vehicle with automatic engine start-stop functionality to utilize the NI state as a transitional shift state, either upon or just prior to engine shutdown, to minimize driveline disturbances. By controlling the NI state, the vehicle driveline is decoupled and torque multiplication is prevented upon engine restart. Execution of an algorithm unloads the engine upon shutdown, and unloads or partially loads the engine as a designated NI clutch reapplies during an engine restart event. The NI clutch may be a component of a multi-speed automatic transmission, e.g., a 6-speed or an 8-speed transmission, having a plurality of torque transfer mechanisms or clutches. One of these clutches is designated as the NI clutch, and this designated NI clutch may be selectively actuated to enter the NI state in conjunction with engine shut down/restart. | 03-31-2011 |
20110290214 | ENGINE SPEED CONTROL SYSTEMS AND METHODS - An engine control system for an auto-stop/start vehicle, comprising: an actuator control module, a correction determination module, and a spark adjustment module. The actuator control module determines a target spark timing for a first time that is between a second time when engine cranking begins and a third time when a measured engine speed becomes greater than a predetermined engine speed after the second time. The correction determination module determines a spark timing correction for the first time based on a target engine speed and a measured engine speed. The spark adjustment module sets a spark timing for the first time based on the target spark timing and the spark timing correction. | 12-01-2011 |
20110295474 | TRANSMISSION LOAD PREDICTING SYSTEM FOR A STOP-START SYSTEM AND A HYBRID ELECTRIC VEHICLE - An engine system of a vehicle includes an engine torque module. The engine torque module determines an engine output torque profile including predicted torque outputs based on an accelerator signal and an engine state variable. A load control module determines a dynamic transmission load profile based on the engine output torque profile and an engine speed profile. The dynamic transmission load profile includes transmission loads as a function of engine speed during an auto-start of an engine. A compensation module generates a torque compensation signal based on the dynamic transmission load profile. An actuator module compensates for a change in a transmission load based on the torque compensation signal and during a transition of the engine from a cranking state to an idle state. | 12-01-2011 |
20120089306 | PRESSURE REGULATION METHOD FOR AN AUTOMATIC TRANSMISSION - A transmission control system for a vehicle includes a transmission control module (TCM), a solenoid valve, a pressure regulator valve, and a transmission element. The TCM includes a control algorithm providing output signals to valve drive electronics, where the valve drive electronics supply current to the solenoid valve. The solenoid valve controls an output pressure located in a passage between the pressure regulator valve and the transmission element. During an engine start-up condition of the vehicle, the control algorithm of the TCM includes control logic for activating a solenoid adjustment algorithm. The solenoid adjustment algorithm decreases the sensitivity of the valve drive electronics when supplying current to the solenoid valve. The solenoid adjustment algorithm is activated for a predetermined amount of time after engine start-up, and is then terminated. Alternatively, the solenoid adjustment algorithm is activated until a vehicle operating condition reaches a particular value, and is then terminated. | 04-12-2012 |
20120283922 | SYSTEM AND METHOD FOR MODEL-BASED NEUTRAL IDLE CLUTCH CONTROL - A vehicle includes an engine, an automatic transmission, and a controller. The transmission includes a neutral idle (NI) state and a designated NI clutch which is selectively actuated to exit the NI state. The controller executes instructions from tangible memory to shift out of the NI state and into a drive state. The controller includes a slip model which generates a desired clutch slip profile as a differentiable time function, and a desired slip derivative of the desired slip profile. The desired profiles are used to calculate a clutch pressure command for controlling the designated NI clutch. The time function may be at least a third order/cubic equation. A method includes executing the slip model to generate the desired clutch slip profile, calculating a desired slip derivative of the desired slip profile, and using the desired slip profile derivative to calculate a clutch pressure command for the designated NI clutch. | 11-08-2012 |
20130023381 | ENGINE POSITION CONTROL IN AN ENGINE STOP-START POWERTRAIN - A vehicle having engine stop-start functionality includes a transmission, engine, and controller. The transmission includes a clutch, and the engine includes a crankshaft. The controller is in communication with the engine and the transmission, and is configured for detecting a commanded shut down of the engine, and then engaging the clutch to control a rate of deceleration of the crankshaft and stop the crankshaft within a calibrated range of a target stop position at the end of engine shut down. A method for controlling engine stop position includes detecting a commanded shut down of the engine, and engaging the clutch after detecting the commanded shut down to thereby control the rate of deceleration of the crankshaft and stop the crankshaft within a calibrated range of a target stop position at the end of shut down of the engine. The transmission may be automatic or it may be a dual-clutch transmission. | 01-24-2013 |
20130072348 | METHOD AND APPARATUS FOR ADAPTIVE CLUTCH CONTROL FOR A VEHICLE HAVING ENGINE START-STOP FUNCTIONALITY - A vehicle includes an engine, torque converter, transmission, accumulator, sensor, and controller. The engine is automatically restarted in response to a start signal during an engine auto-start event. The transmission has a calibrated line pressure and a plurality (n) of clutches. The (n) clutches are engaged to execute the engine auto-start event. The accumulator delivers fluid under pressure to the transmission in response to the start signal. The controller controls (n−1) of the plurality (n) of clutches to the calibrated line pressure in response to detecting the start signal. The controller also modifies clutch fill parameters which control a fill sequence of the remaining clutch, i.e., the designated control clutch, as a function of a deviation of the measured turbine speed from a theoretical no-slip turbine speed. A system includes the transmission, sensor, accumulator, and controller. A method for controlling the designated clutch is also disclosed. | 03-21-2013 |
20130282244 | DETECTION OF AN EXHAUSTING CLUTCH IN A NEUTRAL IDLE-EQUIPPED TRANSMISSION - A vehicle includes an engine, a torque converter, a transmission, and a controller. The transmission has an input member connected to a turbine of the torque converter. The transmission includes a neutral idle (NI) state and a designated NI clutch actuated to enter the NI state. The controller calculates a reference slip error as a function of engine speed and turbine speed, detects when the designated NI clutch is exhausting while operating in the NI state as a function of the reference slip error, and executes a control action when the exhausting NI clutch is detected. A method includes measuring engine and turbine speed, calculating the reference slip error value as a function of the engine and turbine speeds, detecting when the designated NI clutch is exhausting while operating in the NI state using the reference slip error, and executing a control action when the exhausting NI clutch is detected. | 10-24-2013 |
20150032343 | TRANSMISSION WITH CREEP CONTROL INTERVENTION FUNCTIONALITY - A vehicle includes a brake pedal, engine, transmission, and controller. The transmission includes an input member and an input clutch responsive to position control signals. The controller has multiple control modules, each outputting a corresponding torque command. One module is a creep control module which outputs a calibrated creep torque. Intervention logic independently monitors the torque commands during a creep maneuver, with control actions executed when predetermined conditions are present. The torque command from the creep controller determines the position control signals of the input clutch during the creep maneuver, and creep torque is set to zero whenever the brake pedal is sufficiently applied. A transmission assembly includes the input member, input clutch, and controller. A method includes outputting torque commands from each control module, including the creep torque, monitoring the torque commands during the creep maneuver, and executing the control actions when the predetermined conditions are present. | 01-29-2015 |
20150032345 | FEED-FORWARD ENGINE IDLE SPEED CONTROL - A vehicle includes an engine, transmission, engine control module (ECM), and transmission control module (TCM). The transmission includes an input member and an input clutch which selectively connects a crankshaft of the engine to the input member. The TCM identifies a target clutch torque of the input clutch during a creep maneuver of the vehicle, and communicates the identified target clutch torque to the ECM. The ECM maintains engine idle speed at a threshold level through the creep maneuver and a requested launch using the target clutch torque as a feed-forward term. A method includes identifying a target clutch torque of the input clutch during a creep maneuver, and communicating the identified target clutch torque to the ECM. The idle speed is maintained at a threshold level by the ECM through the creep maneuver and a detected launch using the target clutch torque as a feed-forward idle speed control term. | 01-29-2015 |
20150032360 | MONITORING OF TRANSMISSION-TO-ENGINE SPEED REQUESTS - A vehicle includes an engine having a crankshaft which rotates at an engine speed, a transmission having a rotatable input member, a transmission control module (TC), and an engine control module (ECM) in communication with the TCM. The TCM is programmed to execute a transmission-to-engine speed monitoring and control method which includes transmitting an engine speed request to the ECM which requests a positive increase in the engine speed, and terminating the request when the request is active for more than a first calibrated timeout duration. The TCM also terminates the request when the request is active for more than a second calibrated duration that is less than the first calibrated duration, the transmission is not in neutral, and both a shift of the transmission and an acceleration of the input member are not active. | 01-29-2015 |
20150039193 | SYSTEM AND METHOD FOR CONTROLLING THE AMOUNT OF TORQUE PROVIDED TO WHEELS OF A VEHICLE TO PREVENT UNINTENDED ACCELERATION - A system according to the principles of the present disclosure includes an axle torque determination module, an engine torque determination module, a torque security module, and an engine torque control module. The axle torque determination module determines an axle torque request based on a driver input and a vehicle speed. The engine torque determination module determines an engine torque request based on the axle torque request and at least one of a first turbine speed and whether a clutch of a torque converter is applied. The torque security module determines a secured torque request based on at least one of the driver input, the vehicle speed, and an engine speed. The engine torque control module controls an amount of torque produced by an engine based on one of the engine torque request and the secured torque request. | 02-05-2015 |
20150039196 | DETECTION OF AN EXHAUSTING CLUTCH IN A NEUTRAL IDLE-EQUIPPED TRANSMISSION - A transmission assembly for a vehicle includes a transmission and a controller. The transmission includes an input member, at least one clutch and gear set, and an output member. The input member receives an input torque from an engine. The output member receives an output torque from the clutch and gear set(s). The clutch and gear set(s) connect to the input member and establish a plurality of operating states including a neutral idle (NI) state. A designated NI clutch is selectively actuated to enter the NI state when the transmission is in a drive state and the vehicle is stationary. The controller calculates a reference slip error as a function of engine and turbine speed, and detects when the designated NI clutch is exhausting fluid while operating in the NI state using a function of the reference slip error. A control action executes when the exhausting NI clutch is detected. | 02-05-2015 |