Abstract: When an N position sensor is ON, even though the N position is selected, the oil pressure supplied to a clutch C1 which is engaged during the transition from the non-running state to the running state is raised in advance to a predetermined oil pressure; and, if a running request is detected when a D position decision has not been made, irrespective of whether or not a shift lever has been shifted from its N position to its D position, first speed starting off from rest control is performed, in which the oil pressure supplied to the clutch C1 is raised to an oil pressure at which the clutch C1 is capable of power transmission.

Abstract: A transmission device (1) with a hydraulic system (4) comprising a main transmission pump device for supplying various transmission components with hydraulic fluid. The main transmission pump device is driven by torque applied to the transmission input shaft (2). A force flow between the transmission input shaft (2) and transmission output shaft (3) is produced by various hydraulically actuated transmission components. When the hydraulic system (4) is not supplied by the main transmission pump, the force flow is interrupted. The hydraulic system (4) has an auxiliary pump device (5) by virtue of which the hydraulic system (4) too can be supplied with hydraulic fluid. The auxiliary pump device (5) is driven by torque applied to the transmission output shaft (3) at least when the force flow is interrupted.

Abstract: A method of and apparatus for operating an automated mechanical transmission (AMT) achieves switching between and selecting one of a plurality of automated mechanical transmission shift scheduling modes. Such switching or selection occurs and is controlled by the vehicle operator undertaking a sequence of non-routine operating steps or inputs which are interpreted by a microprocessor or controller as a request for a change of the shift scheduling mode.

Abstract: A hydraulic control system for a continuously variable transmission for a hybrid electric vehicle enhances operability as speed changes are made based on input torques and engine rotational speeds since pressure of a primary pulley is controlled based on engine rotational speeds; applies a wide pressure range for solenoids in normal operation by deciding a limp home mode only when a secondary control solenoid valve (SCSV) and a ratio control solenoid valve (RCSV) are under maximum pressure at the same time; reuses flux discharged under reduced pressure from a secondary regulator valve in a lubrication control valve, thus saving energy; controls the lubrication pressure actively using PWM; and generates a pilot pressure for clutch control using a single valve when the transmission control unit fails.

Abstract: A hydraulic control apparatus of an automatic transmission estimates the possibility of there being a demand for a shift into a gear lower than the current gear during a power-off downshift operation. If there is a possibility that there will be a demand for a shift into the next gear during the shift, the hydraulic control apparatus starts an operation for supplying an apply preparation hydraulic pressure in preparation for the shift into that next gear.

Abstract: A method is described for the operation of a transmission device (3) with several shift elements (5, 6) actuated hydraulically by a pressure source (4) for engaging and disengaging various transmission ratios and with several electric actors (7, 8) of a hydraulic system of the transmission device (3) for the adjustment of actuating pressures for the shift elements (5, 6). When an engine start-stop function calls for a combustion engine (2) of a drivetrain comprising the transmission device (3) to be switched off, the energizing current of the actors (7, 8) is adjusted from an operating level (I_B) in which the respective actors (7, 8) are energized with a current appropriate for producing an operating-situation-dependent actuation pressure in the shift elements (5, 6), to a standby level (I_S). When the engine start-stop function calls for the combustion engine (3) to be switched on, the energizing current of the actors (7, 8) is adjusted from the standby level (I_S) to the operating level (I_B).

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 for establishing a plurality of gear ratios. The transfer case is coupled to the transmission by an output shaft. The transmission controller is in communication with a plurality of control devices for controlling the operation of the transmission. The controller includes control logic for controlling the engagement and disengagement of the auxiliary equipment.

Abstract: A method implements a starting process for an internal combustion engine which has a drive unit and a transmission with at least two transmission input shafts and a multiple clutch device, in particular a double clutch device. During the starting process, the first gear is engaged in a first clutch of the multiple clutch device and is activated, while the second gear speed is engaged in a second clutch of the multiple clutch device but not activated. During the starting process, a current velocity is compared with a predefinable reference velocity, and when the reference velocity is reached a control unit causes the first clutch to be opened and thus causes the first gear to be deactivated while, in parallel with this, the second clutch is closed and the second gear is thus activated.

Abstract: A drive unit includes an engine and a transmission having a variable transmission ratio. An instantaneous setpoint power output quantity of the drive unit is determined from an intended power output. The setpoint power output quantity is a function of the instantaneous transmission ratio of the transmission at least for a given intended power output.

Abstract: A method for controlling and/or regulating a multi-step automatic transmission of a vehicle in which an upshift is prevented if a power limit, of the motor of the vehicle, is reached such that, when a driving situation in which the power limit of the motor is reached and recognized, the motor speed (n) is set at a predetermined limit value (nLimit). In addition, a system for implementing the method according to the invention is also proposed.

Abstract: A method for operation of a drive train having a drive machine and an automatic, unsynchronized gearwheel variable-speed transmission, which can be connected to the drive machine by using an automatic clutch is described. A control device carries out a selection process as a function of vehicle parameters and/or operating variables of the motor vehicle to determine whether a gear change of the unsynchronized gearwheel variable-speed transmission will be carried out with the clutch engaged or disengaged. To ensure reliable operation of the motor vehicle, a gear change is carried out with the clutch disengaged in a time interval after initial starting up of the drive train and/or after starting of the drive machine and/or when a malfunction is identified in a component in the drive train.

Abstract: A vehicle includes a direct-start engine and a fuel rail with a threshold fuel pressure, a transmission having a threshold fluid pressure, and a fuel delivery system. The system has a controller, a motor having a shaft, and an integrated pump assembly including a high-pressure (HP) fuel pump and a low-pressure (LP) fluid pump each connected to the shaft. Threshold pressures are maintained during the predetermined engine state, which includes an engine idling and an engine cranking state. A method for providing stop-and-go functionality in a vehicle having a direct-start engine includes detecting a current engine state, rotating a motor shaft to energize a secondary HP fuel pump at a first threshold pressure during engine cranking, and rotating the shaft to energize an LP fluid pump at a second threshold pressure during engine idling and engine cranking. The secondary pumps can also be used when primary pumps are temporarily inoperable.

Abstract: A load control structure for a work vehicle comprises: set rotation speed detection device for detecting a set rotation of an engine of the work vehicle; actual rotation speed detection device that senses an actual rotational speed of the engine; continuously variable speed change device that receives power from an engine of the work vehicle; speed change position detecting device for detecting a speed change operation position of the continuously variable speed change device; operating device for speed-shifting the continuously variable speed change device; control device for controlling the operation of the operating device; wherein the control device calculates a drop amount of the actual engine rotation speed from the set rotation speed based on the detected information from the set rotation speed detection device and the actual rotation speed detection device, and sets a limit operation position for the continuously variable speed change device based on the calculated drop amount and a correlation data t

Abstract: An ECU executes a program including the steps of when an upshift is requested, determining whether engine torque ET changing rate ?ET>threshold value ?ET (1) is established or not: incrementing a recovery timer TE when engine torque ET changing rate ?ET<?ET (2) is established during establishment of engine torque ET changing rate ?ET>threshold value ?ET (1); and initiating an upshift when recovery timer TE>threshold value TE (1).

Abstract: An method of operating a multiple speed (gear ratio) mechanical transmission and engine combination to optimize (reduce) fuel consumption comprises the steps of determining a fuel efficiency map for an engine, providing a multiple speed mechanical transmission controller having data and program storage capabilities, providing data regarding the fuel efficiency map to the controller and providing a control algorithm in the controller whereby operation of the engine/transmission combination is optimized for fuel economy in accordance with the fuel efficiency map.

Abstract: A number of systems and methods are disclosed which increase the replenishment interval for anti-knock fluid. This is especially important during activities which require a large amount of anti-knock fluid, such as towing. In some embodiments, the systems and methods are used to reduce anti-knock fluid consumption. For example, changes to engine operation, such as rich operation, spark retarding, upspeeding, and variable valve timing, all serve to reduce the amount of anti-knock fluid required to eliminate knocking. In other embodiments, the composition of the anti-knock fluid is modified, such as by using a higher octane fluid, or through the addition of water to the anti-knock fluid. In other embodiments, the replenishment interval is increased through a larger anti-knock fluid storage capacity. In one embodiment, a three tank system is used where the third tank can be used to store gasoline or anti-knock fluid, depending on the driving conditions.

Abstract: A gearshift controller for an industrial vehicle, includes: a speed ratio detection unit that detects a speed ratio of speeds of an input axis and of an output axis of a torque converter; a gearshift control unit that shifts up a speed stage when the detected speed ratio is equal to or more than a first predetermined value and shifts down the speed stage when the detected speed ratio is equal to or less than a second predetermined value, which is smaller than the first predetermined value; and an operation member with which a downshift to the first speed is instructed by operation thereof by an operator. When the downshift is instructed by the operation member, the gearshift control unit controls the speed stage to be kept at the first speed for a predetermined time period regardless of the speed ratio detected by the speed ratio detection unit.

Abstract: A method is provided for controlling a vehicle, including receiving an operator input indicative of a desired power for at least one predetermined function, and variably controlling at least one pressure-actuated friction slip clutch in a vehicle powertrain in response to the received operator input in order to control a torque transmitted via the friction slip clutch.

Abstract: The present invention provides a method for controlling engine torque in a hybrid vehicle, in which a point of time when an intake cam is activated is determined such that an engine demand torque is controlled to a level at which system efficiency is maximized within a limited engine output range before activation of the intake cam and the engine demand torque is controlled to a level at which the system efficiency is maximized after activation of the intake cam.

Abstract: A multi-mode internal combustion engine is described. As one example, the engine may be transitioned between a two stroke mode and a four stroke mode in coordination with a transmission shift by adjusting a number of strokes performed by the engine per combustion cycle while shifting the transmission between different gear ratios. Under select conditions, the number of strokes performed by the engine per combustion cycle may be reduced while shifting the transmission from a higher gear ratio to a lower gear ratio. Under other conditions, the number of strokes performed by the engine per combustion cycle may be increased while shifting the transmission from a lower gear ratio to a higher gear ratio.

Abstract: In a powertrain for motor vehicle that includes an engine, an electric machine, a transmission having an input driveably connected to the engine and a transmission output driveably connected to the electric machine, and a powertrain output driveably connected to the electric machine and wheels of the vehicle, a method for controlling torque during a shift includes transmitting engine torque through the transmission to the powertrain output; during a shift, operating the electric machine to modify the torque transmitted to the powertrain output; and storing energy generated by the electric machine during the shift.

Abstract: An automatic transmission shift control apparatus includes a shift point learning-correcting unit and a high acceleration time upshifting unit. The shift point learning-correcting unit executes learning-correction of a shift point during an upshift such that an input rotational speed of the automatic transmission reaches a predetermined target maximum rotational speed. The high acceleration time upshifting unit executes, when predetermined high acceleration is requested, an upshift control based on the shift point in which a learning value of the shift point learning-correcting unit is reflected. When the high acceleration is not requested, the upshift control is performed based on a reference value of the shift point in which the learning value of the shift point learning-correcting unit is not reflected. The shift point learning-correcting unit executes the learning-correction of the shift point when the learning value is reflected in the upshift control.

Abstract: A method for establishing malfunctions of components of a motor vehicle power train as well as the reaction to the same. The power train has a drive motor and an automatic transmission with respectively allocated control devices, setting apparatus and sensors, and the transmission input shaft is allocated a torque sensor for recording the transmission input shaft. During operation of the motor vehicle, the functions of the control devices, the operating elements, the sensors and their data transmission apparatus as well as the measured values of the transmission input torque are recorded and checked for signs of malfunction. After recognizing such a malfunction, operations are conducted by means of which the motor vehicle can be further operated in an emergency type of operation or with the aid of which the driving operation can be safely ended.

Abstract: A method is disclosed for optimizing the gear-shifting sequence in a step-variable transmission fitted in a motor vehicle, in particular in an automated shift transmission, which has a plurality of gears, which can be engaged and disengaged by means of respective clutches, the method comprising the following steps: registering at least one of a tolerance-dependent and a wear-dependent parameter of a clutch of the step-variable transmission; and adjustment of a set-point displacement value of a gear-shifting member of the clutch, which corresponds to the parameter and which is approached in the course of a gear shift, as a function of the value of the parameter registered.

Abstract: A shift control method of a range group transmission with a multi-speed main transmission, which connects with a drive motor, via a clutch (K) and an input shaft. A transmission brake optionally engages the input shaft. At least a two range group is located downstream of the main transmission. A range change shift is accomplished by changing a gear of the main transmission and the range group. The shifting sequence is accelerated by: reducing motor torque and disengaging the clutch (K); disengaging a previous range group gear; synchronizing a new range group gear; disengaging a previous main transmission gear; engaging the new range group gear; synchronizing a new main transmission gear; engaging the new main transmission gear; and engaging the clutch (K) and increasing the motor torque, such that synchronization of the new gear occurs by influencing the input shaft of the main transmission.

Abstract: A shift control device is provided for a vehicle transmission having first and second clutches arranged to be selectively engaged when one of gear ranges in first and second gear groups, respectively, is selected. The shift control device includes a rotational speed detecting section, a deceleration detecting section, a rotational speed estimating section, a gear determining section and a pre-shifting section. The rotational speed estimating section is configured to determine an estimated rotational speed of a drive source after downshifting based on a current rotational speed and a deceleration rate. The pre-shifting section is configured to control the vehicle transmission to achieve a waiting state before switching engagement states of the first and second clutches to obtain a next gear range when the next gear range is on a downshift side of a current gear range and the estimated rotational speed is lower than a first prescribed rotational speed.

Abstract: A shift control system for an automatic transmission may include: a shift speed detector for detecting a current shift speed; a kick-down switch for detecting demand for a kick-down shift; and a control portion completing a shift to a target shift speed according to a predetermined shift pattern before a shift finish point by modifying control duties of off-going and on-coming elements if a shift pattern of a lower shift speed, a gear ratio of which is higher than that of the target shift speed, is passed during the kick-down shift, and then performing a shift to the lower shift speed.

Abstract: A hydraulic control device of an automatic transmission having a pick up unit of a feedback oil passage that is provided in a line pressure oil passage branched from an oil passage communicating an oil pressure source and a pressure regulating port with each other. An influence of an oil pump on a feedback pressure is thus reduced, and a primary regulator valve regulates an oil pressure to a stable line pressure having a small amount of rising. This structure prevents instability of the feedback pressure due to the influence of the oil pump which is caused in the case where a feedback pressure of a primary regulator valve is directly obtained from an oil passage communicating from an oil pressure source to a pressure regulating port.

Abstract: An engine control system comprises a torque determination module, a limit determination module, a torque limit module, and a torque control module. The torque determination module determines a desired torque based on a desired engine speed. The limit determination module determines a torque limit based on one of an engine oil temperature and a transmission fluid temperature. The torque limit module determines a final torque based on the desired torque and the torque limit. The torque control module selectively determines a throttle area based on the final torque. A throttle valve is actuated based on the throttle area.

Abstract: A method and system for controlling a 3?2 shift before stopping of an automatic transmission reduces shift shock as a consequence of an operation of a control duty being delayed according to an angular velocity of an engine at a shift start point in the 3?2 shifting process before stopping. The method includes: detecting driving information; determining whether a 3?2 shift condition before stopping is satisfied; determining, when the 3?2 shift condition before stopping is satisfied, whether a shift control condition is satisfied; and controlling the 3?2 shift before stopping when the shift control condition is satisfied.

Abstract: A vehicle propulsion system includes an internal combustion engine having an engine output, an electro-mechanical transmission and a control system. The engine output is coupled to the transmission output at a speed ratio which is established by one of a plurality of electrically variable or fixed operating modes. Selection and control among the various operating modes is managed by a control in accordance with preferred optimum operating costs.

Abstract: In one embodiment, the present invention is directed to a linear engine comprising: a piston; a linear piston leg comprising two opposite cogged edges including: lowering cogs and raising cogs; at least one lowering segmental cogwheel, the cogs of which correspond to said cogs of one edge of said linear piston leg; at least one raising segmental cogwheel, the cogs of which correspond to said cogs of one edge of said linear piston leg; and a transmission system connecting said cogwheels to a driveshaft; wherein each of said segmental cogwheels comprising at least two opposite cogged segments and two opposite cogless segments.

Abstract: The system controls the propulsion of a motor vehicle with a propulsion system (1) which includes an internal combustion engine (E) with a shaft (S) for coupling to a transmission (2). The system includes an accelerator (A) with an associated sensor devices (S1) for supplying electrical signals indicating the force (FP) applied on the accelerator (A) by the driver, and an actuator device (6) operable to alter the position of the accelerator (A).; sensor devices (S2) supplying electrical signals indicating the speed of rotation (n) of the shaft (S) and/or the vehicle speed (V); and an electronic control unit (SCU) operable to control the propulsion system (1) in dependence on the signals supplied by the sensor devices (S1) and (S2).

Abstract: A system and method for overrun prevention is disclosed. Overrun of a one-way clutch may be prevented by determining a current torque value. When a current torque value approaches a negative value, a shift to a gear without a one-way clutch may be performed. Driving control may be increased by shifting from a gear associated with a one-way clutch when a current torque value approaches a negative value or another shifting parameter determines a shift is necessary.

Abstract: Method for adapting an automated transmission of a heavy vehicle in consideration of a speed sensitive PTO. The method selects appropriate gears based on the constraint that the engaged PTO should remain below a set speed limit. The information about the speed limit of the PTO is used by the transmission control unit to ensure that the engine does not drive the PTO at a speed higher than the given speed limit. The engine speed may also be limited to reduce the engine speed to prevent it from exceeding the allowable PTO speed.

Abstract: An automatic transmission control device for a vehicle includes a gear change operation that is performed based on a throttle opening, a vehicle speed and an engine rotational speed. The automatic transmission control device also obtains a displacement of the throttle opening, determines whether the displacement falls within a predetermined range, and restricts a shift-up when the displacement exceeds the predetermined range.

Abstract: A position shift control apparatus is provided which includes an electrical motor joined to an object through an output shaft and a torque transmission mechanism, a detent mechanism producing elastic pressure to hold the object at a target position, and a motor controller. When torque, which is created by the elastic pressure produced by the detent mechanism and acts on the output shaft during rotation of the motor, is opposite in orientation to that outputted by the motor, the motor controller determines the angular position of the motor, as sampled upon a change in an output from an output shaft position sensor, as a reference angular position of the motor for use in controlling the position of the motor, thereby resulting in a decrease in mechanical load on the detent mechanism and the torque transmission mechanism to ensure the durability and operation accuracy of the apparatus.

Abstract: A controller for crawlers of a trencher receives an indication of the speed of an engine and the speed of an output of a torque converter coupling the engine to an excavating element for digging a trench. Based on the ratio of the speed of the engine and the speed of the output of the torque converter, the controller overrides operator input on the crawlers and stops or slows the trencher when the ratio exceeds a predetermined ranged.

Abstract: A work machine includes an IC engine having an output, an IVT having an input coupled with the IC engine output, and a ground speed actuator. A desired speed sensor associated with the ground speed actuator provides an output signal indicating a slower ground speed. At least one electrical processing circuit is configured for increasing an input/output (I/O) ratio of the IVT, dependent upon the sensor output signal, such that a net torque transfer back-driven from the IVT input to the IC engine output is substantially zero.

Abstract: A method of regulating gear shifts of a transmission driven by an engine includes calculating a first torque error and calculating a second torque error. A compensation torque is determined based on the first torque error and the second torque error. The gear shifts are regulated based on the compensation torque.

Abstract: An energy storage type of dual-drive coupled power distribution system adapted to an all wheel driving (AWD) transportation means having a revolution output end from an internal combustion engine that drives front wheel through a front-wheel transmission assembly by means of an intermediate transmission and control interface or a coupling device providing gear-changing or clutching function, connects the revolving kinetics to drive the revolution input end of a dual-drive type of electromagnetic coupling drive device, and further drives the rear wheel through the other revolution output end of the dual-drive type of electromagnetic coupling drive device made in the construction of a revolving dual-end shaft with both end shafts respectively incorporated to a revolving magnetic field structure and a revolving rotor structure to regulate the power distribution between the front wheel and the rear wheel while being subject to the manipulation by a control device.

Abstract: A hydraulic control device for an automatic transmission includes a first solenoid valve, a second solenoid valve, a third solenoid valve, a preliminary shift speed switching valve, and a hydraulic pressure supply switching valve. A second friction engagement element is engaged at high speed side shift speeds, a low speed that is one of low speed side shift speeds is achieved by engagement of a first friction engagement element and a third friction engagement element, and a high speed that is one of the high speed side shift speeds is achieved by engagement of a second friction engagement element and the third friction engagement element.

Abstract: A power output apparatus that suppresses wearing-out of the components of a transmission connected to a drive shaft and a rotating shaft of an electric motor as well as reducing the a shock imparted to the vehicle. The required drive power is output to the drive shaft by appropriately controlling and internal combustion engine, a power split device, the electric motor and a shifting portion. When the rotational speed of the drive shaft can be estimated, the speed ratio in the shifting portion is changed based on either the detected rotational speed of the drive shaft or the estimated rotational speed of the drive shaft and the rotational speed of the rotating shaft. However, when the rotational speed of the drive shaft cannot be estimated, the speed ratio is maintained in the shifting portion.

Abstract: A shift control apparatus for an automatic transmission having an automatic shift mode and a manual shift mode. The shift control apparatus includes a shift characteristic changing unit for changing the first shift characteristic to a second shift characteristic such that a region for outputting an upshift signal is displaced toward higher vehicle speeds after performing a downshift by the manual operation, a delaying unit for delaying the output of the upshift signal by a predetermined time period according to the vehicle running condition when the vehicle running condition becomes a condition where the upshift signal is to be output according to the second shift characteristic, and an upshift allowing unit for once allowing the output of the upshift signal when the above condition continues after the elapse of the predetermined time period determined by the delaying unit.

Abstract: A method for controlling a hybrid powertrain system including an engine selectively operative in one of an all-cylinder state and a cylinder deactivation state based upon power costs includes determining engine power costs for each operating range state of the transmission, determining a system power cost, selecting a preferred cost and corresponding engine operating points, selecting a preferred operating range state, selecting the engine state, and controlling the engine based upon the selected operating range state, the selected engine state, and the engine operating points.

Abstract: Methods and systems for manipulating inputs relating to transmission shifting events in a hybrid-engine powered vehicle equipped with an electro-mechanical hybrid transmission include sets of preferability factors inputted from engine sensors are combined in a microprocessor or computer with other preferability factors generated during engine and vehicle operation to provide an output for a transmission control module, which may execute an operating range or engine state change. Desirable input speeds for a transmission are determined by defining minimum input speeds for each potential transmission operating range state, and ascribing biasing costs to potential transmission input speeds which are slower than the minimum input speeds defined for each potential transmission operating range state.

Abstract: A work machine including an internal combustion (IC) engine having an output, and an infinitely variable transmission (IVT) coupled with the IC engine output. The IVT includes an adjustable input/output (I/O) ratio. An operator adjustable torque control input device provides an output signal. At least one electrical processing circuit is coupled with the torque control input device and configured for controlling the IC engine output and/or the IVT I/O ratio, dependent upon the output signal from the torque control input device.

Abstract: A work machine includes an internal combustion (IC) engine, and an infinitely variable transmission (IVT) coupled with the IC engine. At least one sensor provides an output signal representing a real-time load value on the IC engine. At least one electrical processing circuit is configured for controlling an output of the IVT, dependent upon a threshold load value for the IC engine and the real-time load value for the IC engine. In one embodiment, the at least one electrical processing circuit includes an engine control unit (ECU) associated with the IC engine, and a transmission control unit (TCU) associated with the IVT. The ECU provides an output signal to the TCU representing the real-time load value. The TCU controls the output of the IVT dependent upon a comparison between the threshold load value and the real-time load value.

Abstract: A work machine includes an internal combustion (IC) engine having an output, and an infinitely variable transmission (IVT) coupled with the IC engine output. The IVT includes a hydraulic module and a mechanical drivetrain module. A pressure transducer is associated with and provides an output signal representing a hydraulic pressure within the hydraulic module. At least one electrical processing circuit is configured for controlling the IC engine output, dependent upon the output signal from the pressure transducer.

Abstract: There is provided a control device for a vehicular power transmitting apparatus of equipped with a differential portion is provided for suppressing a durability decrease of the differential portion or component parts related thereto upon preventing a rotary element of the differential portion from reaching a high-speed rotation. Rotation-stop determining means 72 makes a query as to whether the first rotary element RE1 is lowered in a rotation speed to be stopped during an engine drive mode. If the answer is YES and differential-portion rotation speed determining means 74 makes a positive determination, then engaging-element control-executing means 78 executes engaging element control. This allows a third rotary element RE3 of the differential portion 11, connected to drive wheels 38 via an engaging element of an automatic shifting portion 20, to approach a state available to freewheel.