Abstract: A transmission configured with a speed change control unit which, when upshifting the speed in an accelerator on condition, executes an engagement control including a torque phase control after executing a filling control, which controls the hydraulic control unit in such a way that a hydraulic servo of the engagement side frictional engagement element is filled with hydraulic oil, and a standby control, which controls the hydraulic control unit in such a way that hydraulic pressure for the hydraulic servo is maintained at a preset standby pressure. A correction unit is configured to correct at least one of an execution time of the filling control and the standby pressure to an increment side when a fluctuation in a rotational acceleration of the input shaft exceeding a preset determination reference is detected after the standby control.

Abstract: A method of operating a vehicle drive train having a drive machine, a transmission apparatus having a plurality of shift elements and an output drive. The plurality of shift elements are engaged or disengaged in a power flow for achieving different transmission ratios within the transmission apparatus. The output drive is coupled to a transmission output shaft and the drive machine is coupled to a transmission input shaft of the transmission apparatus. Upon a request to interrupt power flow within the transmission apparatus, between the transmission input shaft and the transmission output shaft, a maximum number of shift elements are transferred to and/or held in an engaged operating state, and the remaining portion of the shift elements are transferred to and/or held in a disengaged operating state with the transmission output shaft being rotatable.

Abstract: A control apparatus and a control method for a vehicular drive apparatus that includes a driving power source, and a power transmission device that transmits power from the driving power source to a drive wheel are provided. It is determined that a malfunction occurs in the power transmission device, when a comparison value remains equal to or above a predetermined value for a predetermined period. The comparison value is obtained by making a comparison between an actual value and a theoretical value that relate to a rotational speed of a predetermined rotational member that constitutes at least a part of the vehicular drive apparatus. The predetermined period is set according to an operating state of the power transmission device. Thus, it is possible to reduce the possibility that it is erroneously determined that a malfunction occurs, and to quickly determine that a malfunction occurs.

Abstract: A system and method for determining a required throttle position and operating a throttle in the required throttle position to attain a required engine speed for fuel cut acquisition is disclosed. A lock-up clutch may be engaged without a shock if a required engine speed is achieved that corresponds to a current transmission speed. Fuel economy may be increased by cutting fuel to the engine when a lock-up clutch is engaged.

Abstract: An automated manual transmission for a vehicle may include a shifting section provided with a plurality of shifting units for implementing different gear ratio between an input shaft and an output shaft, and a variable power transfer unit transferring continuously and variably power of a power providing device to the shifting section in series by self-controllable slip operation, wherein the variable power transfer unit may be disposed between the power providing device and the shifting section.

Abstract: A method for improving starting of an engine that may be repeatedly stopped and started is presented. In one embodiment, the method adjusts a transmission actuator in response to engine combustion during an engine start. The method may improve vehicle launch for stop/start vehicles.

Abstract: In a vehicle including two paths as torque transmission paths from an engine to an output shaft of a transmission, each of the paths provided with a clutch and a transmission mechanism, a gear shift shock due to a torque generated at the moment when the paired gears of the next gear level are engaged is significantly reduced. In normal travel control, a control device sets a transmitted torque capacity of each of the clutches in the two paths at maximum. Also, in the normal travel control, the control device sets the paired gears of the transmission mechanism in a previous path that is one of the paths, in an engaged state, and sets the transmission mechanism in a next path that is the other path, in a neutral state. When a gear shift command is generated, the control device lowers the transmitted torque capacity of the clutch in the next path.

Abstract: When a select lever is in a drive range, a microcomputer reads a value of an output voltage by a switch-operation-signal output circuit after detecting that both shift-up switch and shift-down switch are substantially simultaneously turned on, checks whether or not the output voltage by the switch-operation-signal output circuit is the output voltage indicating that the switch after a predetermined time has elapsed is in a normal condition, and only when the output voltage is such an output voltage, permits a manual mode of an automatic transmission and when the output voltage is not such an output voltage, cancels the manual mode.

Abstract: It is an object of the present invention to provide a compact torque transmission device. The torque transmission device includes an input-side member, an output-side member, a clutch and a pressing mechanism. The clutch is configured to transmit or cut torque between the input-side member and the output-side member. The pressing mechanism includes a pressing member for pressing the clutch, and a pressing device. The pressing device is a device for pressing the pressing member, and is disposed on the inner peripheral side of the clutch.

Abstract: A fail-to-neutral diagnostic technique for a transmission that includes a variator may include monitoring a state of a pressure differential valve fluidly coupled to a high side pressure applied to at least one actuator coupled to at least one corresponding roller of the variator and also fluidly coupled to a low side pressure applied to the at least one actuator, determining from the state of the pressure differential valve a variator torque sign corresponding to whether torque transferred by the at least one roller is positive or negative, determining an expected variator torque sign based on current operating conditions of the transmission, and commanding the transmission to a true neutral condition if the determined variator torque sign is different from the expected variator torque sign.

Abstract: A vehicle includes an engine and transmission. A first rotating clutch engages as an oncoming clutch during a predetermined shift maneuver having a total required clutch energy. A second rotating clutch acts as a holding clutch. A third rotating clutch engages as an additional oncoming clutch during the shift maneuver to share clutch energy with the first rotating clutch. The third rotating clutch, when not engaged, has a zero slip speed relative to the input member. A method includes building a shift table for a transmission design, including identifying slip speed ratios, with respect to the input member, for each clutch, and selecting, from the shift table, a direct drive or other gear state in which three of the rotating clutches are simultaneously operating at a zero slip speed ratio with respect to the input member. The third rotating clutch engages during the shift maneuver.

Abstract: A planetary gear device is provided between a driving wheel and an energy accumulating device. A sun gear of the planetary gear device is connected to an input shaft of the energy accumulating device. A carrier of the planetary gear device is connected to the driving wheel. A torque adjusting device is connected to a ring gear of the planetary gear device. When a regeneration control is not carried out, the torque adjusting device is controlled by a control unit, so that a braking torque generated at the torque adjusting device and applied to the ring gear is controlled in order to make a difference of a rotational speed at a smaller value between the input shaft and the sun gear.

Abstract: A control apparatus for a vehicular automatic transmission configured to selectively establish a plurality of shift positions by engaging respective combinations of two frictional coupling devices of a plurality of frictional coupling devices, with output hydraulic pressures of respective ones of a plurality of solenoid valves provided in a hydraulic control circuit, includes: a normal-state output regulation control portion and an electrically-normal-state determining portion.

Abstract: It is provided a control device of a vehicle power transmission device including a transmission capable of fixing a rotating member with either of engagement of a one-way clutch or engagement of an engagement device, the transmission having a predetermined shift stage formed on condition that at least the rotating member is fixed, if an input torque to the transmission is changed after the engagement of the engagement device, a torque capacity of the engagement device being temporarily reduced without changing the predetermined shift stage, and if a request for applying a driven torque is made during reduction of the torque capacity of the engagement device, the temporarily reduced torque capacity of the engagement device being recovered, and the driven torque being increased depending on a recovery status of the torque capacity.

Abstract: A method of operating a motor vehicle having a drive aggregate, a transmission and a hydraulic system. The transmission has shift elements and, for each gear, only a portion of the elements are engaged while a remainder are disengaged. The hydraulic system has main pump driven by the drive aggregate and an auxiliary pump. The method tests the functionality of the auxiliary pump. The drive aggregate and the main pump are insufficiently driven such that the shift elements can not engage. The auxiliary pump is driven to provide required pressure such that all but one of the shift elements fully engages. The remaining shift element is then first engaged up to its engagement point and then either engaged beyond its engagement point or another unengaged shift element is engaged beyond its engagement point. The functionality of the auxiliary pump is determined based on changes in the drive aggregate's rotational speed.

Abstract: A method for executing a transmission shift in a hybrid transmission including first and second electric machines includes executing a shift-through-neutral sequence from an initial transmission state to a target transmission state including executing an intermediate shift to neutral. Upon detecting a change in an output torque request while executing the shift-through-neutral sequence, possible recovery shift paths are identified. Available ones of the possible recovery shift paths are identified and a shift cost for each said available recovery shift path is evaluated. The available recovery shift path having a minimum shift cost is selected as a preferred recovery shift path and is executed to achieve a non-neutral transmission state.

Abstract: A method and system provides a Brake Transmission Shift Interlock Override mode in a vehicle including a shift-by-wire transmission. With power applied and ignition on, a driver will press and hold an override switch for a calibrated time. While the override switch is pressed, the driver presses a non-Park button for another calibrated time. The result will be that the vehicle is placed in the selected range wherein the transmission will not automatically shift to Park upon detecting a triggering event. The driver is able to shift the vehicle from Park, even if an electrical failure prevents the transmission from shifting out of Park. As such the vehicle can be driven until the failure is serviced.

Abstract: A method and cruise control system for controlling a vehicle cruise control includes driving the vehicle with the cruise control active and set to maintain a vehicle set target speed, and registering a current vehicle condition, which includes at least a current vehicle position, a currently engaged gear ratio, available gear ratios, current vehicle speed, available maximum propulsion torque and road topography of coming travelling road comprising a next coming uphill slope. Based on the current vehicle condition a downshift is predicted at a coming vehicle position in the coming uphill slope due to vehicle speed decrease and at least one activity is selected which results in that the downshift can be postponed or avoided. The cruise control is controlled according to the selected activity in order to postpone or avoid, for example a downshift from a direct gear and thereby saves fuel.

Abstract: A lock-up clutch of a hydrodynamic torque converter remains disengaged during shifts of a downstream transmission, when the drive motor is operated in the partial load range, and remains engaged during shifts of the downstream transmission, when drive motor is operated in a full load range.

Abstract: A hydraulic control system for a dual clutch transmission includes a plurality of solenoids and valves in fluid communication with a plurality of clutch actuators and with a plurality of synchronizer actuators. The clutch actuators are operable to actuate a plurality of torque transmitting devices and the synchronizer actuators are operable to actuate a plurality of synchronizer assemblies. Selective activation of combinations of the solenoids allows for a pressurized fluid to activate at least one of the clutch actuators and synchronizer actuators in order to shift the transmission into a desired gear ratio.

Abstract: A multi-mode transmission includes a plurality of torque transfer clutches fluidly coupled to a hydraulic circuit fluidly coupled to an independently controllable hydraulic pump. Upon detecting an un-commanded activation of one of the torque transfer clutches, operation of the hydraulic pump is disabled, allowable transmission states are identified, and the one of the torque transfer clutches is synchronized. The hydraulic pump is subsequently enabled and the transmission is operated in one of the allowable transmission states.

Abstract: In a hydraulic apparatus for an automatic transmission having a torque converter with a lockup clutch and CVT, there are provided a first control valve for controlling hydraulic pressure supply to the lockup clutch oil chamber, a first electromagnetic solenoid valve for controlling operation of the first control valve, a second control valve for controlling hydraulic pressure supply to the CVT pulleys, a second electromagnetic solenoid valve for controlling operation of the second control valve, a switching valve interposed between the oil chamber and the first control valve. In the apparatus, when detecting that the first control valve or first electromagnetic solenoid valve is failed and the lockup clutch is locked in engaged condition, current supply to the second electromagnetic solenoid valve is stopped so that it operates the switching valve to disengage the lockup clutch, thereby enabling to forcibly release the engagement without manipulation by the operator.

Abstract: One-way clutches OWC1 and OWC2 are provided on output sides of transmissions TM1 and TM2, and the transmissions TM1 and TM2 mechanically lock when the output member 121 of the one-way clutches OWC1 and OWC2 is reversely rotated to the backward side. Clutch mechanisms CL1 and CL2 are interposed between the output member 121 and a driving target member 11 connected to a driving wheel 2. According to uphill start conditions, a controller 5 makes any one of the clutch mechanisms CL 1 and CL2 enter ON state when a vehicle-backward-movement prevention control is determined to be required and the controller 5 makes the clutch mechanisms CL1 and CL2 enter OFF state when the vehicle-backward-movement prevention control is determined to be not required. Thus, it is possible to provide a vehicle driving system capable of performing a hill hold assist function with a simple control.

Abstract: A method for controlling a vehicle powertrain during launch includes controlling slip across a first clutch that transmits engine torque through the first clutch and the current gear while a transmission operates in a current gear other than a launch gear, disengaging the first clutch, engaging the launch gear, and controlling slip across a second clutch that transmits engine torque through the second clutch and the launch gear.

Abstract: A fail-to-neutral diagnostic technique for a transmission that includes a variator may include monitoring a state of a pressure differential valve fluidly coupled to a high side pressure applied to at least one actuator coupled to at least one corresponding roller of the variator and also fluidly coupled to a low side pressure applied to the at least one actuator, determining from the state of the pressure differential valve a variator torque sign corresponding to whether torque transferred by the at least one roller is positive or negative, determining an expected variator torque sign based on current operating conditions of the transmission, and commanding the transmission to a true neutral condition if the determined variator torque sign is different from the expected variator torque sign.

Abstract: A system for preventing damage to a vehicle, such as a truck, is provided. A sensor may be operable to measure a parameter relating to a component in a vehicle and to provide a parameter signal indicative of the measured parameter. A processor may be in communication with the sensor and operable to receive the parameter signal from the sensor. The processor may be further operable to analyze the parameter signal. The processor may be further operable to initiate a damage prevention process including a reduction of heat generation in the vehicle based on the parameter.

Abstract: A method of operating a vehicle drive train having a drive machine, a transmission apparatus having a plurality of shift elements and an output drive. The plurality of shift elements are engaged or disengaged in a power flow for achieving different transmission ratios within the transmission apparatus. The output drive is coupled to a transmission output shaft and the drive machine is coupled to a transmission input shaft of the transmission apparatus. Upon a request to interrupt power flow within the transmission apparatus, between the transmission input shaft and the transmission output shaft, a maximum number of shift elements are transferred to and/or held in an engaged operating state, and the remaining portion of the shift elements are transferred to and/or held in a disengaged operating state with the transmission output shaft being rotatable.

Abstract: The present invention comprehends a plurality of embodiments of a hydraulic control system for various configurations of dual clutch transmissions. The hydraulic control systems all include a regulated source of pressurized hydraulic fluid including an electric pump, a filter and an accumulator, a pair of pressure control valves and a branching hydraulic circuit including pressure or flow control valves, spool or logic valves and two position valves which collectively supply and exhaust hydraulic fluid from a plurality of shift actuators. The actuators are connected to shift rails which include shift forks and are slidable to engage synchronizers and positive clutches associated with the various gear ratios.

Abstract: The present invention comprehends a plurality of embodiments of a hydraulic control system for various configurations of dual clutch transmissions. The hydraulic control systems all include a regulated source of pressurized hydraulic fluid including an electric pump, a filter and an accumulator, a pair of pressure control valves and a branching hydraulic circuit including pressure or flow control valves, spool or logic valves and two position valves which collectively supply and exhaust hydraulic fluid from a plurality of shift actuators. The actuators are connected to shift rails which include shift forks and are slidable to engage synchronizers and positive clutches associated with the various gear ratios.

Abstract: In a gear shift device and a method for operating a manual gearshift device of a motor vehicle including a control unit which, in a gear shift mode is adapted to resolve a recognized tooth butt condition of a gear shift device which is to be engaged positively by a starting clutch, the control unit is adapted to select a starting mode for resolving the tooth butt condition by setting a startup readiness parameter which determines a startup readiness condition as established before the tooth butt condition is resolved for initiating clutch engagement and thereby resolving the tooth butt condition and, at the same time, starting movement of the vehicle.

Abstract: A control system for a transmission coupled to an engine includes first, second, and third modules. The first module detects a closed throttle downshift of the transmission. The second module detects a request for a power-on downshift of the transmission. The third module controls a clutch of the transmission when the request for the power-on downshift is detected during the closed throttle downshift, wherein the third module one of (i) decreases a pressure applied to the clutch to a first predetermined pressure before an end of the closed throttle downshift and (ii) controls a pressure applied to the clutch to a second predetermined pressure at the end of the closed throttle downshift.

Abstract: When an upshift is performed while a traveling condition of a vehicle corresponds to a driving condition or a downshift is performed while the traveling condition of the vehicle corresponds to a coasting condition, a second target slip amount is set as a target slip amount for a period extending from the start of gear ratio variation following issuance of a gear position change start command to completion of the gear ratio change, and when a downshift is performed in the driving condition or an upshift is performed in the coasting condition, a first target slip amount is set as the target slip amount for a period extending from issuance of the shift command to completion of the shift.

Abstract: A gear change control device actuates an actuator in response to an input of a gear change command and sets the clutch in an intermediate state between the engaged and disengaged states before a plurality of gears in the transmission are selectively engaged by dog clutches. In the intermediate state, a driving-side friction member and a driven-side friction member of the clutch are pressed against each other at a pressure lower than in the engaged state. The gear change control device actuates the clutch actuator to restore the friction clutch set in the intermediate state to the engaged state after the plurality of gears are selectively engaged.

Abstract: Controlling means of a work vehicle includes, as speed change output setting data indicative of relationship between operational positions of the operational pedal and outputs from a stepless speed change device, first data for setting a deceleration completion position of the operational pedal where the output from the stepless speed change device is zero to provide a larger operational amount of the operational pedal from a stepping release position and second data for setting the deceleration completion position to provide a smaller operational amount of the operational pedal from the stepping release position.

Abstract: A system and method for selectively engaging and disengaging auxiliary equipment to avoid gear clash in a vehicle is disclosed. The system includes a transmission, a transfer case, and a transmission controller. The transmission has a plurality of gears and the transfer case is coupled to the transmission by an output shaft. The controller includes control logic for controlling the engagement and disengagement of the auxiliary equipment. The control logic has a first control logic for determining whether an operator has actuated a selector switch, a second control logic for actuating a torque transmitting device to engage or disengage the auxiliary equipment and avoid gear clash, a third logic for monitoring the engagement or disengagement of the auxiliary equipment, and a fourth control logic determining whether the auxiliary equipment has been engaged or disengaged.

Abstract: A shift controller with a first clutch CL1 that connects/disconnects the torque to a first main shaft and a second clutch CL2 connects/disconnects the torque to a second main shaft. A transmission is configured so that dog clutches DC1, DC2 for first speed and for second speed are engaged in a predetermined turned position P1-2 of a shift drum. A linear solenoid valve that supplies clutch oil pressure, a shift solenoid that switches a destination of the supply oil pressure between both clutches and a controller that controls the supply oil pressure and the turning of the shift drum are provided. The controller supplies predetermined oil pressure P1 to the CL2 in neutral, switches the destination of supply oil pressure to the CL1 when the shift drum is turned to P1-2 according to a shift instruction to engage gears and supplies maximum oil pressure P3 to the CL1 in predetermined time ta.

Abstract: A method and control module for controlling a transmission of a vehicle includes a clutch torque load predictor module generating a predicted clutch torque load signal for the shift command and a minimum clutch pressure module generating a minimum clutch pressure signal corresponding to a minimum clutch pressure. The control module includes a pressure command module generating a commanded clutch pressure signal for the predicted clutch torque load signal based on the minimum clutch pressure signal and commanding operation of a clutch with a commanded clutch pressure signal. The control module also includes a transmission control module generating the shift command after the clutch torque load predictor module generates the predicted clutch signal, the minimum clutch pressure module generates the minimum clutch pressure signal and the pressure command module generates the commanded clutch pressure signal.

Abstract: A shift control method of an automatic transmission controls a skip shift from a first shift-speed achieved by engagements of first and second frictional elements to a second shift-speed achieved by engagements of third and fourth frictional elements, wherein the engagements of the third and fourth frictional elements is controlled after completion of releases of the first and second frictional elements.

Abstract: In a method and a control unit for controlling the position of an automatic disc clutch in a vehicle, which disc clutch is arranged to transmit motive force from an internal combustion engine to an input shaft of a stagegeared gearbox in the vehicle, the control unit is arranged to position the clutch in a first position, preparing the vehicle for take off, with the gearbox having a starting gear engaged, and where the clutch in the first position transmits a smaller torque, characterized in that the control unit being further arranged to position the clutch in a second more disengaged position compared to the first position, if a driver of the vehicle does not demand vehicle take off torque by activating a throttle control within a predetermined time.

Abstract: In a shift-by-wire gearshift control apparatus, even if a switching anomaly in which switching between forward and reverse gears is not possible has occurred, transmission of driving power to the output shaft 10 can be interrupted as quickly as possible. In the case of the occurrence of a switching anomaly in which switching from a forward gear stage to a reverse gear stage, or vice versa, is not possible, as a path for draining engaging hydraulic pressure supplied to a frictional engagement element (C1 to C4, B1, B2) involved in establishing the current gear stage, the hydraulic control circuit 4 secures an anomaly drain path (91 or 92) that is shorter than a normal drain path (81, 82 or 83) secured by the hydraulic control circuit 4 during normal switching.

Abstract: Methods and systems are provided for pressurizing a transmission hydraulic circuit including a transmission mechanical pump coupled to an engine though a gearbox. One example method comprises, during an engine start, adjusting a speed ratio between the transmission pump and the engine between a first speed ratio and a second speed ratio, the pump rotating faster relative to the engine at the first speed ratio as compared with the second speed ratio. In this way, the pump may be driven at different speed ratios relative to the engine to provide better pressurization in the transmission.

Abstract: A control apparatus of a vehicle transmission includes a hydraulic circuit configured to activate at least one friction element with a control pressure, a selector configured to select a range of the transmission, a valve configured to switch a transmission shifter, and a control unit configured to direct the valve to switch the transmission shifter in response to the selected transmission range and to reduce the control pressure prior to switching the transmission shifter. A method to control a vehicle transmission includes activating at least one friction element with a control pressure, selecting a desired range of the transmission, switching a transmission range in response to the selected desired transmission range, and reducing the control pressure prior to switching the transmission range.

Abstract: A method for monitoring the operation of a drive train of a motor vehicle, the drive train including a drive machine, a clutch and an automated transmission, and the drive train having an emergency program, which enables an emergency operation of the drive train even if important control signals such as engine torque, engine speed, transmission speed are missing, where the emergency operation is initiated as soon as one of the following signals is no longer present: engine torque or a substitute value for the engine torque, torque requested by a driver or a substitute for the torque requested by the driver, engine speed, transmission input speed.

Abstract: A method of controlling output torque in a hybrid or electric vehicle transmissions includes calculating a first long-term output torque constraint and a first short-term output torque constraint. A first effective output torque constraint is determined from at least one of the first long-term and short-term output torque constraints. The first effective output torque constraint is bounded by both of the first long-term and short-term output torque constraints. The method may further include calculating a rate limit, such that determining the first effective output torque constraint includes restricting the magnitude of changes in the first long-term output torque constraint to the calculated rate limit. A spread between the first short-term output torque constraint and the first effective output torque constraint may be measured, and the rate limit calculated as a function of that spread. The rate limit may also be calculated with an inversely-proportional relationship to the spread.

Abstract: A method of controlling a rolling or coasting function of a vehicle with a drive train having a drive motor, an automatic or automated transmission, a controllable shifting means, a brake device and a drive speed control device. The vehicle speed is regulated by the drive speed control device and the braking device is activated, as needed, when driving on a downhill gradient section. To effectively and reliably use the rolling or coasting function in suitable driving situations, taking into account the influence of the driving speed control device, a rolling or a coasting condition for a downhill gradient taper is checked, when driving on the downhill gradient section, and, when the rolling or coasting condition is satisfied, the transmission controls interrupt the flow of power in the drive train before the vehicle entering a flat area, and/or before the driving speed control device generates an engine torque request.

Abstract: A device having a tray defining at least one reservoir designed to contain a liquid, a platform, designed to be placed on the tray and to support a growing substrate, the platform including a flat main portion provided with wells having, at the bottom, an orifice communicating with the liquid contained in the tray, and means for carrying liquid in the reservoir, where a plurality of reinforcing walls protrude perpendicularly upwards from the main portion of the platform, where these walls have sufficient height so that, when the platform is placed on the tray, their top edge forms the highest portion of the device, and where the reinforcing walls are distributed on the surface of the platform so as to allow a distribution of the loads applied to this device.

Abstract: A method of operating a drive-train which comprises an automated shift transmission having an unsynchronized main transmission and a synchronized downstream group that is drivingly coupled downstream from the main transmission. An input shaft of the automated transmission is connected, via a clutch, to a drive aggregate and an output shaft of the automated transmission is connected to a drive axle. When the vehicle is driven and the main transmission is in a neutral position, if the drive aggregate malfunctions, to engage a gear, the downstream group is adjusted to stop transmitting power and thereby coast to a stop. A shifting impulse is applied to a shifting cylinder of the main transmission so that shifting elements, of the main transmission, ratchet over one another and eventually mesh thus engaging the main transmission, and once the main transmission is engaged, the downstream group is brought to a power-flow-transmitting position.

Abstract: A shifting control system has two gear shift stage groups, two clutches, a clutch release detection section, a pre-shift controller, a clutch oil level detection section and a pre-shift inhibiting section. The clutches are alternately engaged to selectively transmit power from an engine to a wheel. The clutch release detection section detects a release-side clutch which corresponds to the clutch that is in a released state. The pre-shift controller operates a meshing mechanism of the gear shift stage group corresponding to the release-side clutch, so as to undergo pre-shifting when the other clutch is engaged as an engage-side clutch. The clutch oil level detection section determines whether an oil level in the release-side clutch is equal to or greater than a preset oil level. The pre-shift inhibiting section inhibits pre-shifting while the oil level in the release-side clutch is equal to or greater than a preset oil level.

Abstract: A gear change control device is provided for a straddle-type vehicle having a clutch and a transmission. The device includes a clutch actuator configured to engage and disengage the clutch. A transmission actuator is configured to change a gear of the transmission. At least one sensor is configured to sense an operational condition of the straddle type vehicle. At least one switch is configured to generate a gear change command. A controller is operatively connected to the clutch actuator, the transmission actuator, the at least one sensor, and the at least one switch. The controller is configured to change gears in response to the gear change command and during the gear change reengage the clutch under either a first control routine or second, different control routine based upon the operational condition of the straddle-type vehicle determined by the at least one sensor.

Abstract: A transmission configured with a speed change control unit which, when upshifting the speed in an accelerator on condition, executes an engagement control including a torque phase control after executing a filling control, which controls the hydraulic control unit in such a way that a hydraulic servo of the engagement side frictional engagement element is filled with hydraulic oil, and a standby control, which controls the hydraulic control unit in such a way that hydraulic pressure for the hydraulic servo is maintained at a preset standby pressure. A correction unit is configured to correct at least one of an execution time of the filling control and the standby pressure to an increment side when a fluctuation in a rotational acceleration of the input shaft exceeding a preset determination reference is detected after the standby control.