Abstract: An automatic transmission hydraulic control circuit for controlling forward and reverse hydraulic clutches provided in an automatic transmission for setting a vehicle to a selected state among forward, reverse and neutral states, includes a main pressure transmission line for selectively transmitting a main pressure for operating only one at any time of the forward or reverse hydraulic clutch, forward/reverse selecting valves for switching the main pressure transmission line to set the vehicle to the selected state; and a neutral valve for interrupting transmission of the main pressure setting the vehicle to the forward or reverse state opposite to the selected state when the forward/reverse selecting valves cannot operate. The main pressure is supplied to the hydraulic clutches via the forward/reverse selecting valves as well as the neutral valve.

Abstract: An electronic control system for an automatic transmission has an electronic control unit including a CPU and a memory. The control program is programmed based on an object-oriented programming. An object such as a domain control unit or individual control parts are provided for driving a corresponding linear solenoid valve. A shift request output unit determines types of required shift and outputs a shift request message including the shift type. The domain control unit determines a method to be executed in response to the shift type ID. Preferably, the shift request output unit further determines whether the shift is a single shift or a multiple shift and whether the shift is a normal shift or a special shift. These determination results are also included in the shift request message, so that the domain control unit varies the method to control the linear solenoid valves.

Abstract: A control for sensing impending and existing electrical connection faults in a vehicular transmission control circuit (42) including a plurality of individually energized and de-energized electrical devices such as electric motors (36 and 38) and solenoid-controlled valves (24 and 30). A voltage monitor (46) senses voltage drop across a power source (44) for properly operating devices and compares it to an expected voltage drop (REF) to determine if an electrical connection fault condition exists.

Abstract: The power train of a motor vehicle has an automated transmission and/or an automated clutch, at least one control unit and at least one actor receiving signals from the control unit and serving to control the operation of the automated constituent or constituents of the power train. A preferably reestablishable connection can be interrupted in the event of a malfunctioning of the power train, such as exhaustion of the supply of electrical energy, defectiveness of the actor and/or defectiveness of the automated constituent or constituents and/or defectiveness of the motion transmitting connection or connections between the actor and the automated constituent or constituents. This renders it possible to set the transmission in neutral or into another gear and/or to select the condition of the clutch in such a way that the vehicle can advance to a selected destination under it own power or that it can be towed to such destination.

Abstract: A shift device for an automatic transmission generates no manual shift demand in response to a plurality of operator shift demands. A steering wheel has an up-down select switch. A range selector has an upshift switch and a downshift switch in addition to an automatic mode switch. An operator shift demand may be generated through any one of the steering mounted switches and the select lever. A control unit has an operator upshift demand input terminal and an operator downshift demand input terminal. The control unit has a circuit that generates a two-level up signal and a circuit that generates a two-level down signal. The up signal has an “OFF” level indicative of absence of an operator upshift demand on the operator upshift demand input terminal. It has an “ON” level indicative of presence of an operator upshift demand on the operator upshift demand input terminal.

Abstract: In a control unit of an automotive vehicle, it is possible to securely prevent a tie-up due to a miss-recognition of a disengage timing of a disengage side friction device, securely prevent an early disengage due to an erroneous recognition of the disengage timing and realize a control of accurately and reliably shifting the clutch.

Abstract: A manual valve arrangement is provided for an automatic transmission which provides for uninterrupted friction element control even though manual valve porting is being switched. An extra multi-select solenoid combined with porting through the manual valve and dual acting ball check assemblies permits selected friction elements to be controlled from two solenoids simultaneously. The extra multi-select solenoid, which is a normally-open solenoid valve, permits an energy savings logic mode in which the a normally-closed solenoid valve can be de-energized. Output from the extra multi-select solenoid is switched to different clutch elements when the manual valve is moved from the reverse position to the drive position and from the drive position to the second position.

Abstract: An automatic transmission control system having gearing that establishes multiple forward driving ratios and a reverse ratio as well as a neutral mode, an electrohydraulic control valve circuit for controlling the application and release of clutch and brake elements for the transmission gearing, a driver-controlled range selector for transmitting operator commands to shift control logic, and a failure mode management circuit that monitors the shift control logic and the response of the transmission system to operator commands, as well as the transmission range selector signals delivered to the shift control logic whereby multiple control redundancies in the electronic range control system ensure that system failures and component failures develop an error signal to alert the driver of possible malfunctions during the range selection period.

Abstract: Hydraulic pressure regulated by a first pressure control valve is supplied to an electromagnetic changeover valve. The electromagnetic changeover valve changes over the hydraulic pressure between a low & reverse passage communicating with a low & reverse brake and a high clutch passage communicating with a high clutch, thereby a simultaneous engagement of the low & reverse brake and the high clutch can be avoided and further the simplification of the hydraulic control apparatus of an automatic transmission can be realized.

Abstract: When the solenoid valves constituting the transmission ratio control valve should fail electrically, the toroidal continuously variable transmission shifts the transmission ratio toward the speed increasing side to avoid possible dangers of a car while traveling and at the same time cancels variations of the spool valve movement caused by the control oil pressures of the solenoid valve. The two solenoid valves that control the oil pressures acting on the both ends of the transmission ratio control valve having a spool valve are of opposite types, a normally open type and a normally closed type. The duty A and duty B for these solenoid valves are set to equal values (S11). Even when any of the solenoid valves are electrically failed, the transmission ratio of the toroidal speed change unit in the toroidal continuously variable transmission is shifted toward the speed increasing side, which is a safe side for the running car.

Abstract: A hydraulic circuit for a transmission, according to the present invention, comprises a regulator valve (31), a plurality of control valves (34, 35, 45), a restrictor (41), a bypass oil passage (61), a bypass closing valve (42), and a signal pressure generating valve (48). The regulator valve regulates oil discharged from a hydraulic pump driven by a motor to produce line pressure. The plurality of control valves control an operation of the transmission using the line pressure. The control valves include at least one electric control valve. The restrictor is formed on a discharge oil passage which is connected to the regulator valve. The bypass oil passage connects the upstream side and the downstream side of the restrictor while bypassing the restrictor. The bypass closing valve is closable the bypass oil passage by receiving oil pressure produced when the electric control valve breaks down.

Abstract: A plurality of shift control valves for independently controlling the supply of hydraulic oil to, and the discharge thereof from, a plurality of hydraulic engaging elements are divided into a first group of shift control valves which establish a predetermined-speed transmission train and a second group of shift control valves corresponding to the other hydraulic engaging elements. A fail-safe valve is interposed between an oil supply passage which is connected to a hydraulic pressure source and the second group of speed change control valves. The fail-safe valve is switched to a closed position in a condition in which the hydraulic oil is supplied to all of such plurality of hydraulic engaging elements as are not to be engaged at the same time, whereby the oil supply passage is connected only to the first group of shift control valves. Each of the first group of shift control valves is provided with an oil chamber for urging it toward an oil supply position.

Abstract: The present provides a shutdown shift schedule which allows a vehicle driver an increased number of gear states to increase driveability. This method monitors the gear state conditions indicative of the gear state which said automatic transmission is in. When the shift state conditions vary from predetermined standards, the controller uses the shutdown shift schedule in place of the shift schedule for changing gears of the automatic transmission. This shutdown shift schedule is adapted to allow a 3-1 shift when the shift solenoid is in a shift D position and the shift state is 3. The shutdown shift schedule is also adapted to allow a 3-2 shift when the shift state is 3 and the shift solenoid is in the shift 2 position.

Abstract: In an electronically controlled automatic transmission, when it determines that the position of the selector lever is located at a position other than a neutral position, it compares the time varying ratio of the number of revolutions of the output shaft with a first prescribed value, and when it determines that the time varying ratio is greater than the first prescribed value, a control device performs a temporary gear change prohibiting process to temporarily prohibit a gear change of the automatic transmission. Accordingly, an abnormal state of an output shaft revolution sensor can be sensed without the provision of a vehicle speed reed switch.

Abstract: The invention relates to a control system, in particular an emergency control system, of an automatic clutch. The clutch can operate with slip controlled by the driving speed when engaged, or can be disengaged or remain disengaged when the engine speed is excessive, and can also be disengaged when there is an idling signal.

Abstract: A powertrain has a multi-speed transmission with an electro-hydraulic control system for establishing the operating conditions of the transmission. The control system has a plurality of shift or relay valves that are each alternatively positioned by a spring or a solenoid controlled pressure bias. One of the relay valves, which controls two friction devices, has a latching mechanism which will retain the valve in the pressure set condition until the pressure in one of the friction devices is decreased below a predetermined pressure. The latch mechanism will also serve to retain the transmission in a low forward ratio if an electrical discontinuance should occur when the transmission is conditioned for the low forward ratio. The control will also permit retention in the highest forward ratio if electrical discontinuance occurs during operation in this ratio. Following an engine shutdown and restart, the transmission can be selectively operated in a reverse ratio, a neutral condition or the third forward ratio.

Abstract: An electronic transmission control system having a fail-safe system for an automotive vehicle with a continuously variable automatic transmission whose speed-change ratio is changeable continuously depending on vehicle speed and engine load, comprises a hydraulic modulator producing at least a regulated line pressure necessary to adjust the speed-change ratio hydraulically, a desired speed-change ratio arithmetic processing section for calculating a desired speed-change ratio based on the vehicle speed and the engine load, and a desired line pressure arithmetic processing section for calculating a desired line pressure based on the desired speed-change ratio and the engine load.

Abstract: A shift control unit is provided in an electric-power-assist transmission which offers good operatability. A shift disabling unit employs a neutral-position detecting unit, a vehicle-speed judging unit, an engine-rotational-speed judging device, an OR circuit and an AND circuit. The neutral-position detecting unit is used for outputting an "H"-level signal to indicate that a gear is placed at a neutral position. The vehicle-speed judging unit generates an "H"-level signal for a speed of a vehicle equal to or higher than 10 km/h. On the other hand, the engine-rotational-speed judging device generates an "H"-level signal for a rotational speed of an engine equal to or higher than 3,000 rpm. The OR circuit generates an "H"-level signal when the vehicle-speed judging unit generates an "H"-level signal or the engine-rotational speed judging device generates an "H"-level signal.

Abstract: A control system controls the output of a power source of a vehicle having a continuously variable transmission and a gear ratio to be set by the continuously variable transmission. The control system determines a target driving force on the basis of an output demand and a vehicle speed, and determines a target output of the power source for achieving the target driving force. The control system determines a target output speed preset for the target output, and controls the gear ratio of the continuously variable transmission so that the actual output speed of the power source may become the target output speed. The control system further determines the target output torque of the power source on the basis of the target output and the actual output speed of the power source, and controls the power source to achieve the target output torque. When the gear ratio is to be changed, its changing rate is made different in at least two quick and slow states.

Abstract: A display system for an automatic transmission including: a first range switching mechanism for switching a shift range by a mechanical operation; and a second range switching mechanism activated by electric enabling mechanism for switching the shift range by an electric operation. The display system comprises: a first display device for displaying the shift range which is selected by the first range switching mechanism; a second display device for displaying the active state of the enabling mechanism; and a third display device for displaying the shift range which is selected by the second range switching mechanism activated by the enabling mechanism.

Abstract: An automatic clutch between a motor vehicle engine and drive train with a manually shifted gearbox disposed on the clutch output side. Rotational speed differences between the clutch input and output detected by sensor technology are taken into consideration when the clutch is engaged. If the signals from the sensing elements for the rotational speed on the output side fail, replacement signals are calculated from other parameters.

Abstract: An automated shifting system for a manual transmission having a neutral clutch connecting an engine to a multiple ratio transmission, the transmission having servo operated gear shift mechanism. A driver-controlled gear shift switching mechanism is used to activate the servos that effect ratio range changes. A gear shift switching mechanism includes multiple switches for triggering operation of the servos that control the ratio range changes. A range sensing redundancy strategy for the ratio range switches provide improved protection against an unintended change in direction due to three-bit separation between bits of the valid codes and to a range sensing switch failure strategy by identifying when a range change commanded by the driver exhibits a single-point fault condition.

Abstract: To provide a deceleration controlling apparatus for an automotive vehicle, which may perform a deceleration control that is effective in a breakdown of a throttle valve kept opened, without increasing a cost, the deceleration controlling apparatus for an automotive vehicle, includes: an engine, an accelerator pedal and a brake system which are mounted on the vehicle; an automatic transmission connected to the engine; a throttle valve for adjusting an amount of intake air of the engine; an accelerator opening degree sensor for detecting an opening degree of the accelerator pedal to output an accelerator opening degree signal; a throttle valve controlling unit for electrically controlling an opening degree of the throttle valve in response to the accelerator opening degree signal; a throttle opening degree sensor for detecting an opening degree of the throttle valve to output a throttle opening degree signal; a throttle-open breakdown detecting unit S3 for detecting a breakdown of throttle-open of the throttle

Abstract: A drive system for a hybrid drive vehicle, comprises a driving mechanism which includes a clutch, an engine connected the clutch, a first motor for generating power, connected to the clutch, a second motor for driving a drive wheel, connected to the clutch, and a transmission connected to the clutch. A third motor is provided for driving a hydraulic pump of a hydraulic system for the transmission. A first inverter is connected between the first motor and a battery, in which charging and discharging between the first motor and the battery being made through the first inverter. A second inverter is connected between the second motor and the battery, in which charging and discharging between the second motor and the battery being made through the second inverter. A third inverter is connected between the third motor and the battery, in which changing and discharging between the battery and the motor being made through the third inverter.

Abstract: When the ETV control system runs into trouble, drivability and safety are secured against the system trouble by fixing the step of speed change at a high speed position if the vehicle is running forward or stopping fuel feed to a specific cylinder or cylinders if it is running backward. When the electronic throttle control system runs into trouble, the throttle valve 3 is released from control by stopping power supply to the motor 1, the throttle value 3 is mechanically fixed in a preset position, and the transmission 2 is fixed in a high speed position if the vehicle is running forward, thereby to reduce engine acceleration and the shock to the body due to unnecessary speed change action, or fuel feed to a specific cylinder or cylinders is stopped according to the engine condition if the vehicle is running backward, thereby to reduce the engine output, so that the vehicle be enabled to run smoothly.

Abstract: A hydraulic control system for an automatic transmission includes a pressure regulator for regulating hydraulic pressure produced in an oil pump, and a plurality of valves selectively supplying the regulated hydraulic pressure to a first number of friction elements. A second number of solenoid valves controls operation of the first number of friction elements by controlling supply of the regulated hydraulic pressure to the plurality of valves; wherein the second number is less than the first number. A manual valve controls supply of the regulated pressure to the second number of solenoid valves.

Abstract: An apparatus for controlling an automatic transmission is disclosed. A 2nd speed is established in which hydraulic pressure is supplied only into an engaging chamber of a 2-4 brake by a first duty solenoid valve so that the brake is applied. A 3rd speed is established in which the hydraulic pressure is supplied into a releasing chamber of the brake and a hydraulic chamber of a 3-4 clutch by a second duty solenoid valve under the condition of the hydraulic pressure being supplied into the engaging chamber of the brake so that the brake is released and the 3-4 clutch is engaged. When the 2nd speed is changed to the 3rd speed, a controller increases the hydraulic pressure supplied into the releasing chamber of the brake and the hydraulic chamber of the 3-4 clutch in a case where a failure, in which the first solenoid valve is fixed under a condition that the first solenoid valve supplies the hydraulic pressure into the engaging chamber, is detected.

Abstract: A method and apparatus are provided for controlling the hydraulic line pressure in an automatic transmission for a vehicle in response to the measured pressure and torque transmitted through the transmission such that a minimum hydraulic line pressure is provided to the frictional elements to achieve a non-slip condition through the transmission which increases transmission efficiency and fuel economy. Hydraulic line pressure is controlled by activating a solenoid activated valve. Control signals are based on measured hydraulic line pressure, engine speed, turbine speed, vehicle speed, driver selected gear, and torque converter operating condition for the solenoid actuated valve. The present invention further provides a closed-loop adaptive control technology to learn the minimum line pressure to compensate for variability in the clutch return springs, friction characteristics, surface finishes, as well as hydraulic wear, and changes over the life of the transmission.

Abstract: An electronically controlled power shift transmission for a vehicle includes an oil pressure source which generates oil pressure, a clutch which is adapted to be engaged to move the vehicle when oil pressure is supplied to the clutch, a shift valve which is movable between a first position in which oil pressure is supplied to the clutch and a second position in which oil pressure to the clutch is cut off, and a solenoid valve for changing the position of the shift valve. The shift valve drains the oil pressure in the clutch when the shift valve cuts off the oil pressure supplied to the clutch.

Abstract: A control system for an engine transmission provided with a coupling mechanism for engaging or disengaging coupling of the transmission. The control system has one or more valves movable between two positions for controlling engagement and disengagement of the coupling mechanism. The valves are connected to an automatic control unit which has an intermittent signal supply trigger for supplying an intermittent pulsed signal to the valves, thereby providing an intermittent movement of the valves between the two positions.

Abstract: The present invention relates to a control apparatus for a vehicle equipped with an electronic throttle control unit (drive by wire) as electronic throttle control means and an automatic transmission, and the object of the invention is to provide a control apparatus for a vehicle which is capable of ensuring stable travel even in the case where a throttle valve is stuck by a failure of an electronic throttle control unit. In a control apparatus for a vehicle equipped with electronic throttle control means for electrically driving a throttle valve by drive means and an automatic transmission having a plurality of speed change gear stages, the control apparatus is provided with sticking judgment means for judging whether or not the throttle valve has been stuck, and speed change regulation means for inhibiting use of a predetermined gear stage among the speed change gear stages of the automatic transmission in the case where the throttle valve is judged to have been stuck by the sticking judgment means.

Abstract: A control method/program for rapidly confirming engagement of a target gear ratio (GR.sub.T) in an automated mechanical transmission system (92) on the basis of input signals (ES, or IS, OS) indicative of transmission input shaft (18) and output shaft (58) rotational speeds.

Abstract: An improved vehicular automated splitter-type mechanical transmission system. The splitter section is retained engaged in its currently engaged splitter ratio at power-down until vehicle speed falls below a reference (OS<REF?) or the main section (12) is shifted into neutral (GR=N?).

Abstract: An automated clutch between the engine and the variable-speed transmission in the power train of a motor vehicle is operated by a control unit which receives signals from several circuits and/or sensors via one or more conductors. The control unit shifts from a normal operating mode to an emergency mode when one or more sensors and/or circuits and/or conductors are defective. When in emergency mode, the control unit disengages the clutch when the driver starts the engine while the vehicle brake or the parking brake is applied. This ensures that the engine can drive the vehicle as soon as the transmission is shifted into a forward gear or into reverse gear and the application of the brake or brakes is terminated because the control unit is then again free to engage the clutch. Furthermore, such mode of operation enables the driver to shift the transmission into or from a selected gear in response to the application of a relatively small force to the gear shifting lever.

Abstract: A shift control system of an automatic transmission sets a predetermined gear stage by applying a first frictional engagement element and releasing a second frictional engagement element. A pressure regulating mechanism regulates an oil pressure to be fed to or drained from the first frictional engagement element. A failure detector detects a failure of an apparatus to participate in the regulation and control of the oil pressure which is to be fed to or drained from at least one of the first and second frictional engagement elements. A gear stage inhibitor inhibits the setting of the predetermined gear stage if the failure is detected by the failure detector.

Abstract: There are prevented shocks that will occur when a switchover speed changing is made to transfer from one speed changing, in the midst of that speed changing, to another speed changing when the input and output speed ratio "Gratio", which serves a control parameter, is not accurately detected. For that purpose, there is used a flag FGFAIL for setting "1" when the input and output speed ratio "Gratio", at the time of non-speed changing, does not lie within a predetermined range based on the gear ratio of the speed stage that is being established at that time. A switchover speed changing in which switching to another speed changing is made during a speed changing is prohibited when FGFAIL=1.

Abstract: In an automatic transmission in which the electronic control instrument (13) detects, outside the circuits, a fault in the input values (18 to 20), the couplings and the brakes (A to F). When a fault is present for an extended period, the electronic control instrument (13) detects a symptom and switches to a replacement gear. Hereby maximum driveability is ensured without a diagnosis entry.

Abstract: A hydraulic emergency control for a gear-ratio-dependent change in hydraulic fluid pressures in a first and second hydraulic bevel-gear axial adjuster of a continuously variable transmission (10), is provided in which a pump (1) supplies at least the piston chamber (17) of the second axial adjuster, and at least one downstream pressure limiting valve (40) limits the fluid pressure there and moreover from this supply, via a continuous path valve (20), supplies the piston chamber (13) of the first axial adjuster, and the continuous path valve (20) is controlled with the aid of a pressure differential acting on a throttle valve (39) that is downstream of the pump (1) and is integrated with a switching valve (30).

Abstract: A hydraulic control system for an automatic transmission, including a hydrualic pressure source, a hydrualic pressure regulator, a transmission mode selector, a shifting controller for automatically controlling shifting between transmission speeds in a given transmission mode, and a hydrualic pressure control mechanism for controlling quality and responsiveness of the shifting between transmission speeds. The hydrualic control system includes a fail safe valve for assuredly maintaining a certain transmission speed (such as third speed) when a transmission control unit (TCU) fails, or when a valve in the control system sticks or becomes inoperative.

Abstract: A device for controlling a driving force which is mounted between a vehicle motor and the wheels of a motor vehicle controls at least to reduce the force flow between the vehicle motor and the wheels in response to a drive signal. The vehicle motor is controlled by the device of a motor control. The drive signal is formed in dependence upon a detected fault in the motor control. The force flow between the vehicle motor and the wheels is especially then interrupted when an emergency shutoff of the motor can cause a high drag torque on the wheels and therefore a driving situation critical with respect to safety. The device for controlling the driving force is comprising a clutch downstream of the motor, an automatic or automated transmission, and a converter bridge clutch which can bridge the torque converter downstream of the vehicle motor.

Abstract: The power train of a motor vehicle has an electronic unit which controls the condition of an automated clutch between the engine and a manually shiftable transmission. The control unit has a normal or standard operating mode when the various sensors which are connected with and transmit signals to the control unit (as well as the signal transmitting connections such as buses and/or cables) are not defective, and a standby or emergency mode when one or more sensors and/or connections are (temporarily or irreversibly) defective. The control unit then prevents the clutch from permitting or causing a creeping or crawling movement of the vehicle while the engine is idling and the transmission is shifted in a gear other than neutral. The mode of operation of the control unit can be changed back to normal in response to termination of a faulty operation of one or more sensors and/or connections, for example, with a predetermined delay.

Abstract: An automatic transmission control system is equipped with a pressure modulating valve for regulating the engaging pressure to be supplied to frictional engagement elements for setting respective gear stages of the automatic transmission, a signal pressure output valve for providing signal pressure, and a switching valve.

Abstract: A method and a circuit configuration for gear detection in a motor vehicle transmission detect a signal corresponding to an input rpm and a signal corresponding to an output rpm of the transmission. A quotient of the output rpm to the input rpm is formed. A gear that has been engaged is detected from this quotient and from a known gear ratio of the transmission. A variation over time of the ratio of the output rpm to the input rpm of the transmission is ascertained and compared with a limit value. If the limit value is exceeded, a determination is made that no gear has been engaged.

Abstract: In an automatic transmission of an automotive vehicle equipped with a change-speed gear train capable of selectively establishing first-speed to fourth-speed drive power trains, there are provided first and second solenoid valves each in the form of a normally open valve arranged to be supplied with fluid under pressure at its output fluid passage in a deactivated condition, third and fourth solenoid valves each in the form of a normally closed valve arranged to permit fluid under pressure discharged from its output fluid passage in a deactivated condition, a first spool valve for fail-safe arranged to disengage a first hydraulic brake of the change-speed gear train when all the solenoid valves are supplied with the fluid under pressure at their output fluid passages or when the fourth solenoid valve and either one of the first, second and third solenoid valves are supplied with the fluid under pressure at their output fluid passages, and a second spool valve for fail-safe arranged to disengage a second hydra

Abstract: A method of shifting in a manual mode of an electronically-controlled automatic transmission system includes the steps of determining whether a shift lever of a shift lever mechanism is presenting a position error when the shift lever is in a manual position, determining whether at least one switch on the shift, lever mechanism is presenting an error if a shift lever position, error is not determined, determining whether a temperature of an, automatic transmission or engine coolant temperature exceeds a predetermined threshold if the at least one switch is not presenting an error, determining whether the manual position conditions have been met, determining whether an upshift or downshift of the automatic transmission is scheduled if the manual position conditions have been met, and executing either an upshift or a downshift of the automatic transmission based on the determined upshift or downshift being scheduled.

Abstract: The present invention relates to an apparatus and a method for automated controlling of an engageable and disengageable torque transmitting system and of a shifting a transmission in a power drive of a propulsion unit of an automotive vehicle, having at least one actuator for gear shifting and for operating the torque transmitting system, and having a control unit for controlling the at least one actuator and, further, having at least one sensor connected in signal-transmitting communication with a control unit. The sensor is arranged to operate between the control unit and the transmission and to monitor conditions in the transmission during automated shifting and to detect a predetermined condition while the system is disengaged and, upon detection of such predetermined condition, to undo, at least temporarily and at least partially, the preceding gear shifting, and to thereafter resume gear shifting.

Abstract: The hydraulic control system for an automatic transmission having a plurality of friction elements includes a pressure regulator which regulates hydraulic pressure produced by an oil pump, a plurality of valves selectively supplying hydraulic pressure to the plurality of friction elements, and a pressure controller controlling and selectively supplying hydraulic pressure to a plurality of pressure control lines operationally connected to the plurality of valves and at least one of the plurality of valves. The plurality of valves include a first valve operationally controlled by hydraulic pressure in a first one of the pressure control lines to pass the hydraulic pressure output by the pressure controller to at least one of the plurality of friction elements in each operational range except a first speed stage of a drive range.

Abstract: The invention relates to a continuously variable transmission. The continuously variable transmission according to the invention is designed such that in operating conditions to be defined in more detail the transmission ratio is kept essentially constant, in particular for travelling through bends, on inclines, in case of an emergency stop and during a transmission overspeeding. The constant transmission ratio is obtained while the input r.p.m. of the transmission is changing.

Abstract: An integral control system for an engine and an automatic transmission of a vehicle, in which the automatic transmission capable of setting a plurality of running and stop ranges is connected to an engine capable of having output characteristics matching the ranges. A range set in the automatic transmission is detected, and the engine is controlled when a failure of plural ones of the ranges is detected by the range detecting means, in accordance with the ones, as minimizing the engine torque, of the engine output characteristics corresponding to the detected ranges.

Abstract: A control system for controlling automatic shifting of a manual/automatic transmission is disclosed including a cruise control system and an auto-shift mode for controlling automatic upshift and downshift operations between the top two gears of a heavy duty truck transmission. Certain failures of equipment or incorrect driving habits of operators are corrected for with algorithms which prevent undesirable operating conditions which compromise the acceptability of an electronically controlled heavy duty truck transmission equipped vehicle. The mechanism by which auto-shift operation of the transmission is requested is also compared with parameters such as vehicle speed and engine speed in order to determine whether gears should be engaged or disengaged, the gears being those subject to auto-shift control of the system controller.