Class / Patent application number | Description | Number of patent applications / Date published |
701061000 | Using a transmission ratio as feedback control | 22 |
20080249693 | METHOD OF SELECTING A TRANSMISSION SHIFT SCHEDULE - A method for selecting a shift schedule for a transmission in a motor vehicle is provided. The method includes the steps of determining whether a signal-to-noise ratio exceeds a threshold and calculating a tractive effort of the motor vehicle. A vehicle mass and a road grade is then estimated from the tractive effort using a recursive least squares estimator with multiple forgetting when the signal-to-noise ratio exceeds the threshold. A vehicle mass is selected and the road grade estimated from the vehicle mass and tractive effort when the signal-to-noise ratio does not exceed the threshold. A shift schedule is then selected based on the vehicle mass and the estimated road grade. | 10-09-2008 |
20080300761 | Control apparatus for vehicular power transmitting system - A control apparatus for a vehicular power transmitting system including (a) an electrically controlled differential portion which has a differential mechanism and a first electric motor connected to a rotary element of the differential mechanism and which is operable to control a differential state between a rotating speed of its input shaft connected to a drive power source and a rotating speed of its output shaft by controlling an operating state of the first electric motor, and (b) a switching portion operable to switch a power transmitting path for transmitting power from the drive power source, between a power transmitting state and a power cut-off state, the control apparatus including a control range setting portion configured to set one of two different control ranges of a rotating speed of the output shaft, depending upon whether the power transmitting path is placed in the power transmitting state or said power cut-off state, by the switching portion. | 12-04-2008 |
20090043468 | CONTROLLING SYSTEM FOR VEHICLE WITH CONTINUOUSLY VARIABLE TRANSMISSION - A controlling system for a vehicle with a continuously variable transmission, which can render a sufficient accelerating feeling in responsive to a driver's requirement. A controller, upon judgment of an acceleration requirement, sets a target drive force higher than the target drive force upon normal calculation upon normal operation of an accelerator pedal, and sets a target rotation speed for acceleration higher than the target rotation speed upon the normal operation and increasing with an increase of the vehicle speed by a predetermined gradient. The speed change ratio of the continuously variable transmission and the output torque of the engine are controlled such that the set target drive force is achieved, and an input shaft rotation speed of the continuously variable transmission coincides with the target rotation speed for the set acceleration. Thus, upon acceleration requirement by the driver, the target drive force increases and the output rotation speed of the drive source increases so that the sufficiently high accelerating feeling from the vehicle can be obtained. | 02-12-2009 |
20090112424 | Propulsion system with a continuously variable transmission - One disclosed embodiment relates to a propulsion system for a machine. The propulsion system may include a prime mover operatively connected through a continuously variable transmission to a propulsion device. The propulsion system may also include propulsion-system controls that control an operating parameter of the continuously variable transmission, which may include adjusting the operating parameter based on operator input. Controlling the operating parameter may also include determining an adjustment limit for the operating parameter based on one or more operating conditions and applying the adjustment limit to the operating parameter to modify at least one of acceleration and jerk of the machine based on the one or more operating conditions. | 04-30-2009 |
20090319144 | SHIFT CONTROL APPARATUS OF A CONTINUOUSLY VARIABLE TRANSMISSION AND METHOD OF DETERMINING WHETHER SHIFT CONTROL APPARATUS IS OPERATING NORMALLY - The invention provides a shift control apparatus of a continuously variable transmission, which includes a feedback control portion which executes feedback control that brings an actual speed ratio close or equal to a target speed ratio, and a normal operation determining portion which determines whether the shift control apparatus is operating normally based on a difference between the actual speed ratio and the target speed ratio, and an amount of change in the actual speed ratio and an amount of change in the target speed ratio during a predetermined interval. | 12-24-2009 |
20100057316 | CONTROLLER FOR AUTOMATIC TRANSMISSION - In a controller for a belt-type continuously variable transmission including a hydraulic actuator that changes a groove width of a primary pulley, a hydraulic actuator that changes a groove width of a secondary pulley, and a belt clamping pressure control solenoid that controls the hydraulic pressure supplied to the hydraulic actuator of the secondary pulley, a mechanism calculates a transmission ratio between the primary pulley and the secondary pulley and determines whether or not there is belt slippage based on that calculated transmission ratio, and a mechanism determines normalcy of the belt clamping pressure control solenoid. The input torque when belt slippage has actually occurred, i.e., when a failure has been determined, is used as a condition when performing the normalcy determination. By setting such a condition, it is possible for a normalcy determination threshold value (input torque value α) used for the normalcy determination to be a small value, and thus it is possible to suppress erroneous normalcy determination. | 03-04-2010 |
20100131164 | SYSTEMS AND METHODS FOR CONTROL OF TRANSMISSION AND/OR PRIME MOVER - Disclosed here are inventive systems and methods for a powertrain of an electric vehicle (EV). In some embodiments, said powertrain includes a continuously variable transmission (CVT) coupled to an electric drive motor, wherein a control system is configured to control the CVT and/or the drive motor to optimize various efficiencies associated with the EV and/or its subsystems. In one specific embodiment, the control system is configured to operate the EV in an economy mode. Operating in said mode, the control system simultaneously manages the CVT and the drive motor to optimize the range of the EV. The control system can be configured to manage the current provided to the drive motor, as well as adjust a transmission speed ratio of the CVT. Other modes of operation are also disclosed. The control system can be configured to manage the power to the drive motor and adjust the transmission speed ratio of the CVT taking into account battery voltage, throttle position, and transmission speed ratio, for example. | 05-27-2010 |
20100185370 | METHOD FOR CONTROLLING AN AUTOMATIC MULTI-STEP REDUCTION GEAR - The invention concerns a method for controlling an automated multi-step change-speed transmission of a motor vehicle, which is connected on the input side via at least one controllable friction clutch to a drive motor in the form of an internal combustion engine, and on the output side via an axle drive to the drive wheels of a driven axle, and which comprises a plurality of starting gears (G | 07-22-2010 |
20110077829 | CONTROL OF A CONTINUOUSLY VARIABLE TRANSMISSION - A method is described for operating a vehicle fitted with a continuously variable transmission (CVT) and having a lever for varying the transmission ratio of the CVT to permit the vehicle operator to vary the vehicle wheel speed. In the invention, the transmission ratio of the CVT is limited to a value dependent upon at least one of the prevailing engine speed and the rate of change of the engine speed. | 03-31-2011 |
20110087411 | ELECTRONIC CONTROLLER FOR A CONTINUOUSLY VARIABLE TRANSMISSION AND A METHOD OF CONTROL OF A CONTINUOUSLY VARIABLE TRANSMISSION - The invention concerns an electronic controller for a continuously variable transmission of the type having a variator ( | 04-14-2011 |
20120029778 | METHOD FOR OPERATING A TRANSMISSION DEVICE WITH A PLURALITY OF FRICTION-LOCKING AND POSITIVE-LOCKING SHIFTING ELEMENTS - A method of operating a transmission device comprising friction-locking and form-locking shift elements for obtaining different gear ratios. A shift request for engaging a shift element undergoes a time delay dependent upon an operating state prior to a time of engagement of the shift element. A rotational speed differential between halves of the shift element lies within a rotational speed differential window required for the engagement procedure is assigned to the time of engagement. A gradient of the transmission input speed is ascertained at the time of the shift request, and the actual gradient is subsequently monitored and compared with the gradient that existed at the time of the shift request. If an absolute deviation greater than a threshold value is ascertained, the time delay is changed or an actuation of another shift element to be disengaged is varied such that the deviation is reduced below the threshold value. | 02-02-2012 |
20120179344 | Method of Controlling a Hydraulic Continuously Variable Transmission - A method of controlling a hydraulic CVT of a vehicle comprises: determining a speed of rotation of a driving shaft; determining a speed of rotation of a driven shaft; determining a ratio of the speed of rotation of the driving shaft versus the speed of rotation of the driven shaft; determining an engine torque; determining a base clamping force to be applied by the driving pulley onto the belt based on the ratio and the engine torque; determining a desired speed of rotation of the driving shaft; determining a corrective clamping force by comparing the speed of rotation of the driving shaft to the desired speed of rotation of the driving shaft; and controlling a hydraulic pressure applied to a movable sheave to apply a sum of the base and corrective clamping forces onto the belt. A vehicle having a CVT controlled by the method is also disclosed. | 07-12-2012 |
20130080007 | Method of Controlling a Hydraulic Continuously Variable Transmission - A method of controlling a hydraulic CVT of a vehicle comprises: determining a speed of rotation of a driving shaft; determining a speed of rotation of a driven shaft; determining a ratio of the speed of rotation of the driving shaft versus the speed of rotation of the driven shaft; determining an engine torque; determining a base clamping force to be applied by the driving pulley onto the belt based on the ratio and the engine torque; determining a desired speed of rotation of the driving shaft; determining a corrective clamping force by comparing the speed of rotation of the driving shaft to the desired speed of rotation of the driving shaft; and controlling a hydraulic pressure applied to a movable sheave to apply a sum of the base and corrective clamping forces onto the belt. A vehicle having a CVT controlled by the method is also disclosed. | 03-28-2013 |
20130110364 | SHIFT-BY-WIRE SYSTEM FOR AUTOMATIC TRANSMISSION OF VEHICLE | 05-02-2013 |
20130116901 | METHOD AND DEVICE FOR ASCERTAINING A ROTATIONAL SPEED PARAMETER FOR DETERMINING A SETPOINT TORQUE - A method for ascertaining a rotational speed parameter for determining a setpoint torque for driving a drivetrain. The drivetrain comprises a first and at least one second drive assembly for driving a hybrid vehicle. The first drive assembly can be coupled to the drivetrain by means of a clutch. The second drive assembly is mechanically coupled to the drivetrain. When the hybrid vehicle is being driven by means of at least the first drive assembly, the rotational speed parameter corresponds to the value of a shaft rotational speed. When the hybrid vehicle is being driven only by means of the second drive assembly, the rotational speed parameter corresponds to the value of a determined rotational speed. | 05-09-2013 |
20130218429 | CONTROL DEVICE OF CONTINUOUSLY VARIABLE TRANSMISSION FOR VEHICLE - A control device of a continuously variable transmission that controls an input-side thrust force of an input-side variable pulley and an output-side thrust force of an output-side variable pulley to set an actual gear ratio to a target gear ratio and prevent a slip of the transmission belt. The continuously variable transmission having a lowest-speed-side gear ratio determined by mechanically preventing movement of an input-side rotating body moved in an axial direction for varying an effective diameter of the input-side variable pulley, if it is determined that a detection value of a rotation speed for calculating the actual gear ratio does not reflect an actual rotation speed, a target input-side thrust force and a target output-side thrust force being set to be target thrust forces for maintaining the lowest-speed-side gear ratio and preventing a slip of the transmission belt, and, based on whether the actual gear ratio is already the lowest-speed-side gear ratio, the control device differentiating control methods of the input-side thrust force and the output-side thrust force each of which is independently controllable to adjust a pressure in order to obtain the target thrust. | 08-22-2013 |
20130289841 | SHIFT CONTROL DEVICE AND CONTROL METHOD FOR CONTINUOUSLY VARIABLE TRANSMISSION - A continuously variable transmission ( | 10-31-2013 |
20140074366 | CONTROL SYSTEM AND METHOD FOR CONTINUOUSLY VARIABLE TRANSMISSION WITH VARIATOR SPEED RATIO CLOSED-LOOP FEEDBACK - A system and method of controlling a continuously variable transmission with variator speed ratio (VSR) closed-loop feedback is provided. The method includes determining a desired VSR based on at least one of the driver and vehicle inputs, determining a motor position adjustment needed to adjust the position of a roller to achieve the desired VSR, driving the motor based on the determined motor position adjustment needed, sensing a transmission output speed as the motor is being driven, determining an actual VSR as the motor is being driven, and providing closed-loop feedback corresponding to any difference between the actual VSR and the desired VSR and driving the motor to eliminate the difference, thereby achieving the desired VSR with improved quick response time and more accurate control. | 03-13-2014 |
20140257656 | RETARDING DOWNSHIFT MANAGEMENT - A retarding unit in a vehicle is automatically controlled based on conditions including a current setting of the retarding control, downhill grade, speed, current gear, and impending gear change. With the retarder control set in the high position, when the vehicle is operating at a downhill angle greater than the low angle threshold and less than the high angle threshold, and the pending gear is a large step downshift, automatically setting a retarder level to a low retarder level. When the vehicle is operating on level ground and the pending gear is a large step downshift or the current gear is first or second gear, automatically setting the retarder level to off. When the vehicle is operating on flat ground and the deceleration is above a trigger level, automatically setting the retarder level to a low retarder level. | 09-11-2014 |
20140372002 | METHOD OF DETERMINING A CURRENT OPERATING RANGE OF A TRANSFER CASE - A method of determining a current operating range of a transfer case includes continuously calculating current Combined Drive Ratio (CDR), and categorizing the current CDR into one of a pre-determined number of expected CDRs. Counters are used to track when the current CDR is identified as an expected CDR. The different counters are then analyzed using simple mathematical operations to identify which gear ratio the transfer case is currently operating in. | 12-18-2014 |
20160003354 | CONTROL APPARATUS FOR CONTINUOUSLY VARIABLE TRANSMISSION - The apparatus is configured to compare the calculated value (NDRCMDZ) of the desired input shaft rotational speed with the desired input shaft rotational speed upper limit (#NDRCMDMX) set in relation to an energy supply cut-off rotational speed (NEFC), determine the desired input shaft rotational speed upper limit (#NDRCMDMX) as the desired input shaft rotational speed (NDRCMD) when it is determined that the calculated value (NDRCMDZ) does exceed the desired input shaft rotational speed upper limit, and determine the calculated value (NDRCMDZ) as the desired input shaft rotational speed (NDRCMD) when it is determined that the calculated value does not exceed the desired input shaft rotational speed upper limit (#NDRCMDMX). | 01-07-2016 |
20160097451 | METHOD FOR CONTROLLING SLIP OF A CONTINUOUSLY VARIABLE TRANSMISSION - Disclosed herein is a method for controlling slip of a continuously variable transmission using a transmission control unit (TCU), comprising: receiving, by a transmission control unit, information related to determination of slip which occurs during vehicle's running; calculating a slip determining coefficient by the transmission control unit; determining, by the transmission control unit, whether the slip has occurred according to the slip determining information and a predefined slip determining algorithm; and selecting and switching to, by the transmission control unit, one of a plurality of preset slip modes based on the slip determining coefficient and a result obtained by determining whether the slip has occurred. | 04-07-2016 |