Abstract: A fail-safe mechanism of an air induction control apparatus for automotive engines is provided which is designed to hold a throttle valve at a middle position when a valve actuator has failed to move the throttle valve. The fail-safe mechanism includes a middle position hold stopper, an opener lever connected to the throttle shaft, and a first and a second coil spring. The first coil spring works to exert a first spring pressure on the opener member in a first rotational direction in which the throttle valve is rotated from a fully opened position to the middle position. The first coil spring is urged at an end thereof into constant engagement with the middle position hold stopper to hold the opener member from rotating in a second rotational direction opposite the first rotational direction. The second coil spring has a first and a second end between which the opener member extends. The first end abuts against the middle position hold stopper.

Abstract: An adaptive fuel limit function (52) for protecting an internal combustion engine. The adaptive fuel limit function is a learning function responsive to trends in an engine performance parameter such as compensated fuel consumption per unit of power produced (62). The engine performance parameter is processed through a low pass filter (64) to allow changes in a fuel limit signal (54) in response to gradual changes in the fuel demand, such as may be due to wear in the engine, while blocking changes in the fuel limit signal in response to sudden changes in the fuel demand, such as may be due to a cylinder failure. The difference between the input and the output of the low pass filter may be processed to identify a failure level (88) for providing an alarm function distinct from the learning function.

Abstract: An engine control system for monitoring torque increase during cylinder deactivation for a displacement on demand (DOD) engine includes a throttle and a controller. The controller adjusts a preload of the throttle prior to a cylinder deactivation event and determines whether a DOD fault is present during the cylinder deactivation event. The controller one of operates the engine without the preload in the deactivated mode and switches the engine back to the activated mode if the fault is present for a predetermined time. The controller cancels the preload if the DOD fault is present and resets the preload if the predetermined period has not expired. The DOD fault includes one of an engine speed fault, a transmission gear fault and a fueled cylinder fault.

Abstract: A method and an apparatus for protecting an engine are disclosed which are capable of preventing damage to the engine or associated parts thereof. The engine is provided with an electronic control fuel injection system. A quasi-abnormality of at least one of variables in connection with the engine and the associated parts thereof, such as an engine cooling water, a fuel pressure or the like is detected by a sensor. When the quasi-abnormality of the variable and such a quasi-abnormal state lasts for a predetermined period of time, a throttle opening of an electronic control throttle is regulated so as to limit an engine rotational speed to a low rate.

Abstract: An engine cylinder induction air quantity measuring apparatus includes a controller to calculate an intake manifold inside air quantity of air in an intake manifold of the engine, from a sensed intake air quantity by performing a balance calculation to calculate a balance between an intake manifold inflow air quantity of air flowing into the intake manifold, and an intake manifold outflow air quantity of air flowing out of the intake manifold. In an engine stopping process to stop the engine, the controller controls a throttle opening of a throttle valve to a predetermined stop mode opening greater than an idling mode opening for an idle operation of the engine.

Abstract: A watercraft has an engine that is controlled by an electronic control unit and the engine is controlled by an electronic throttle. The electronic throttle is actuated by a motor that is controlled by and electronic control unit. The ECU operates the electronic throttle according to a torque request from an operator. The electronic throttle is also periodically and/or at predetermined time intervals actuated to ensure proper operation of the throttle valve.

Abstract: A control system and method for controlling position of a device by replacing the combination of a feedforward term, a calibrated step, and an integration term in a control scheme with an adaptive feedforward term. An embodiment is provided including a flow control valve on an internal combustion engine. The invention includes characterizing the flow control valve, and determining an error term, based upon monitored position and commanded input to the flow control valve. The adaptive feedforward term is determined based upon the monitored position, the characterization of the flow control valve, and the error term. The flow control valve is controlled to a position, based upon the adaptive feedforward term and the error term. When an absolute value of a derivative term, i.e. a time-rate change of the monitored position, is less than a preset value, the control system updates the characterization of the flow control valve.

Abstract: A servo-assisted butterfly valve for an internal combustion engine comprising a valve seat, a butterfly body engaging the valve seat, a shaft on which the butterfly body is keyed, an electric actuator coupled to the shaft, an elastic member which is adapted to exert a torque on the shaft which tends to rotate the butterfly body towards a limp-home position and an abutment body which comprises an eccentric member which forms an abutment surface for an abutment member of the elastic body in order to stop, in the desired limp-home position, the rotation of the butterfly body caused by the elastic body in the absence of action by the electric actuator.

Abstract: A failure detection apparatus for an internal combustion engine includes failure detecting means (S22-S30) for detecting abnormality of fresh air quantity detecting means (air flow sensor) based on the result of comparison between a fresh air quantity detected by the fresh air quantity detecting means (air flow sensor) and a fresh air quantity reference value set by fresh air quantity reference value setting means (S20), and exhaust flow rate adjusting means. The fresh air quantity reference value setting means sets the reference value (S16) in accordance with not only the operating state (engine speed Ne, fuel injection quantity Qf, etc.) of the engine but also a target adjustment amount (target throttle valve opening) set for the exhaust flow rate adjusting means by target adjustment setting means (S12, S14).

Abstract: An on-vehicle engine control apparatus carries out engine drive control and throttle control using one single CPU and improves safety. The apparatus includes a load relay for feeding a power to a motor that controls throttle valve opening, a first IC (integrated circuit element) containing a CPU, and a second IC connected to the first IC via serial interfaces. The apparatus further includes a first mutual diagnostic device incorporated in the first IC and diagnoses operation of the second IC, a second mutual diagnostic device incorporated in the second IC to diagnoses operation of the first IC, and a detector for detecting an abnormality in operation of each system involved in throttle valve control. Operation of the load relay is controlled based on diagnostic results and abnormality detection results of the first and second mutual diagnostic devices.

Abstract: An ECU is equipped with an engine control microcomputer for executing engine control and a throttle control microcomputer for executing throttle control. The engine control microcomputer is programmed to execute a monitor program. A time in the engine control microcomputer is set with a predetermined time each time the monitor program is executed normally. The timer switches automatically its output logic level at a port from high to low, when the time count reaches zero. When the output logic level is switched to low, a throttle motor is disabled.

Abstract: The present invention relates generally to combustion engines, and more specifically, to an apparatus for controlling the power of combustion engines which have electrically-modulated throttle systems (also known as drive-by-wire throttle systems). There are many applications in which it is desirable to modify the throttle control system of vehicles, for example, in limiting the power production of trucks operating in under ground mines. It is prohibitively expensive for vehicle manufacturers to supply such modified vehicles, so a system must be provided and installed as an after market product. The invention provides a simple and inexpensive solution in the form of a voltage modifying device which can be installed inline, between the accelerator pedal sensor and the engine control unit. The voltage modifying device can be designed to limit the power of the engine, or alter the performance profile in a desired manner.

Abstract: A drive control circuit generates a conduction drive output responsive to a detection output of an accelerator pedal depression degree sensor and an air-intake throttle-valve opening sensor, and controls a driving switch element connected to an air-intake throttle-valve opening control motor. A monitoring control circuit drives a control circuit power supply interruption element that closes a control power supply circuit of the driving switch element, and stops control operation of the driving switch element by a conduction-inhibit output. The drive control circuit can stop operation of a power supply interruption element by a feed-inhibit output. At the time of starting operation, a status signal determines activeness of the feed-inhibit output and conduction-inhibit output, after confirming that those outputs are normal, the inhibition is released.

Abstract: A failure diagnosis apparatus for a throttle valve actuating device is disclosed. The throttle valve actuating device has an actuator for actuating a throttle valve provided in an intake system of an internal combustion engine and biasing elements for biasing the throttle valve to a predetermined retention opening. A feedback control of the throttle valve is performed so that an opening of the throttle valve coincides with a first predetermined opening. After the throttle valve is controlled to the first predetermined opening, a feedback control of the throttle valve is performed so that an opening of the throttle valve coincides with a second predetermined opening. It is determined that the throttle valve actuating device has failed when the time period during which the opening of the throttle valve remains in a predetermined determination range including the second predetermined opening, is shorter than a predetermined time period when performing the feedback control to the second predetermined opening.

Abstract: A method to control the position of a throttle valve in the presence of a fault. The method works independently of throttle position in an open-loop mode. The method assures that the throttle plate will assume the default position if: 1) the return spring is functional and the motor is functional; 2) the return spring has failed but the motor is functional; or 3) if the return spring is functional but the motor has failed. This method does not need to detect loss of return spring functionality and it does not need to detect loss of motor functionality. The detected fault that initiates the action need not be related to either the return spring or the motor.

Abstract: To provide a throttle valve control apparatus which simultaneously realizes quick response and stability even when the throttle valve gets stuck in its operation. The apparatus conducts control where a small control coefficient is used to emphasize the convergence stability when the deviation is large. In addition, the apparatus includes a coefficient limiting unit (14) which can gradually increase the control coefficients based on the predetermined permissible changes as the deviation decreases with the elapse of time. This enables the throttle valve control apparatus which simultaneously realizes the quick response and stability by using the controlled variable calculated from the gradually increased control coefficients to drive the throttle valve even when the throttle valve gets stuck, and its motion encounters an obstruction.

Abstract: A control system of an internal combustion engine includes a timing changing unit that changes opening and closing timing of an intake valve relative to rotation of an output shaft of the engine, a working angle changing unit that changes a working angle of the intake valve, a throttle mechanism including a throttle valve provided in an intake passage of the engine and an actuator that is operable to open and close the throttle valve, and an intake air quantity control unit that controls the timing changing unit, the working angle changing unit and the throttle mechanism so as to control an intake air quantity of the engine to a target intake air quantity. The control system detects a failure of at least one of the timing changing unit, the working angle changing unit and the throttle mechanism, and, upon detection of a failure, executes a selected one of difference fail-safe control processes corresponding to different forms of failures, depending upon the form of the detected failure.

Abstract: The invention is directed to a method and an arrangement for determining a driver command and especially a kickdown command. This driver command is only detected when the pedal position or a desired value derived therefrom exceeds a pregiven threshold value and when the gradient of the pedal position or the desired value derived therefrom exceeds a pregiven threshold value.

Abstract: An engine ECU comprises a control CPU for executing engine control and a watchdog circuit for monitoring the CPU. The watchdog circuit stores, whenever a reset signal is outputted to the CPU, a reset information indicating a fault record. The CPU executes, after it is once reset and re-started, the predetermined fail-safe process based on the reset information stored. When a monitor CPU connected to the control CPU for making communication is used as the watchdog circuit, fault detection times X and Y are specified to satisfy the relationship of X≧Y, when the communication fault detection time is defined as X and the watchdog pulse fault detection time as Y.

Abstract: An ECU 2 performs ON/OFF judgments on an ignition switch. When the ignition switch is OFF, a judgment is made whether or not voltage learning for a fully opened position of a throttle valve 34 is complete. If complete, an electric power for a DC motor 31 is cutoff. A TPS output voltage value is read in, and a judgment is made whether or not a given period of time has elapsed. If the given period of time has elapsed, and if a throttle position sensor output voltage value VTPS is equal to or greater than a given value, then a judgment is made that there is a return spring 35 breakage failure. Breakage to the return spring 35 can thus be reliably detected.

Abstract: A method for controlling a positioning device (34) of an internal combustion engine includes the step of providing an electric motor (30) for actuating a positioning device (34). A user employs an actuator (21) to command the throttle plate (34) to change to a commanded position. A motor effort sensor (38) then detects a control effort required by the motor (30) to change to the commanded position. A throttle control unit (28) determines whether the control effort exceeds a threshold for a predetermined time period. If the control effort exceeds the threshold for the predetermined time period, the throttle control unit (28) actuates the motor (30) to reduce the control effort.

Abstract: An engine torque control apparatus for controlling the output torque of an engine (60) connected to a transmission (40) in a vehicle has a temperature sensor (55) for detecting the temperature of oil used by the transmission (40), and a controller (50) for limiting the output torque of the engine to an engine torque limit or less. The controller (50) functions to compare the oil temperature with a specific temperature, to set the engine torque limit to a first limiting value when the oil temperature is equal to or less than the specific temperature, and to increase the engine torque limit at a predetermined increase rate when the oil temperature exceeds the specific temperature.

Abstract: The invention relates to a method for operating an internal combustion engine, whereby the fuel is supplied by means of at least one injection valve. The injected quantity of fuel is influenced by the injection time. The aim of the invention is to be able to operate the internal combustion engine in such a way that comfort and emissions are optimised. To this end, it is predicted whether the required injection time of the injection valve is longer than a maximum possible injection time. If this is the case, at least one determining variable for the combustion is influenced in such a way that the torque (M) is gradually reduced.

Abstract: An engine torque control apparatus for controlling the output torque of an engine (60) connected to a transmission (40) in a vehicle has a temperature sensor (55) for detecting the temperature of oil used by the transmission (40), and a controller (50) for limiting the output torque of the engine to an engine torque limit or less. The controller (50) functions to compare the oil temperature with a specific temperature, to set the engine torque limit to a first limiting value when the oil temperature is equal to or less than the specific temperature, and to increase the engine torque limit at a predetermined increase rate when the oil temperature exceeds the specific temperature.

Abstract: An engine control system and method monitors torque increase during cylinder deactivation for a displacement on demand engine. A timer is started at cylinder deactivation. A controller adjusts throttle position and determines whether cylinder deactivation completes within a predetermined time. The controller adjusts throttle position based on the status of an enable condition. The controller determines if engine speed and vehicle acceleration are each within a threshold. The controller operates the throttle in a preload operating mode if the enable condition is met and operates the throttle in a normal operating mode if the enable condition is not met.

Abstract: In a control system of an internal combustion engine including an intake flow control valve disposed downstream of a throttle valve, a controller controls opening and closing of the intake flow control valve, depending upon an operating state of the internal combustion engine. Upon detection of a failure in the intake flow control valve, the controller controls an intake air amount or flow rate to a different value.

Abstract: Adequate controllability is ensured when feedback control is provided to both the EGR valve and the intake throttle valve, and switching shock is prevented when control is switched from one to the other. The present apparatus comprises an EGR valve, an intake throttle valve, feedback control means for providing feedback control to the EGR valve and intake throttle valve such that the actual EGR volume approximates the target EGR volume corresponding to the running condition of the engine, and limiting means for limiting the operable opening ranges of the EGR valve and intake throttle valve in accordance with the target EGR volume. During EGR control of one valve, feedback control is provided to the other valve and the target opening is constantly calculated. The actual operations are merely limited, so these operations can start from the optimal opening and the switching shock can be prevented when a switch is made to the control of the other valve.

Abstract: A propulsion system for a watercraft includes an engine. An air intake device delivers air to a combustion chamber. A throttle valve regulates an amount of the air. A control device sets the throttle valve to a desired position. A remote controller provides the control device with the desired position. The engine can include an auxiliary intake device that delivers supplemental air to the combustion chamber. A control valve normally shuts the supplemental air from the combustion chamber. The control device determines whether an abnormal condition occurs in setting the throttle valve to the desired position. The control device determines whether the amount of the air is insufficient. The control device controls the control valve to allow the supplemental air to move to the combustion chamber when the control device determines that the abnormal condition occurs and the amount of the air is insufficient.

Abstract: In an engine speed control system for an outboard motor having a throttle valve that regulates air to be sucked and an actuator connected to the throttle valve to move it in an opening direction or in a closing direction, the actuator is driven to move the throttle valve in the closing direction such that the engine speed drops, if it is discriminated that a detected engine speed exceeds a predetermined speed (set to a speed at which the engine can assumably continue to run until the boat has returned to port), when a trouble has occurred in the engine. Thus, the system can lower the engine speed so as to allow the boat to return to port, without causing the engine to vibrate, when a trouble has occurred in the engine.

Abstract: A method for operating an internal combustion engine includes the steps of determining a pressure in a suction portion from a position of a throttle flap, passing a signal produced from the position of the throttle flap through a delay element, using the passed signal for forming a limit for a permissible value region, utilizing as the delay means mechanism at least two delay elements, such that a delay of one of the delay elements is switched off when a speed with which the position of the throttle valve changes lies above a positive limiting value, and the delay of the other delay element is switched off when the speed with which the position of the throttle valve changes lies below a negative limiting value.

Abstract: A system and method wherein a torque monitoring algorithm compares torque demand (i.e., driver-demanded torque computed primarily from acceleration pedal position), with two independent torque estimates (e.g., one estimated from throttle position and one estimated from mass airflow (MAF) to the intake manifold). If the maximum of the two actual torque estimates exceeds the driver-demanded torque, the monitoring algorithm logic intervenes in engine torque production (e.g., shuts off fuel to cylinders) and lights a service (wrench) light. In order to prevent, or minimize, unnecessary engine torque production intervention, reducing a torque demand signal to the throttle by a factor, such factor being a function of airflow meter load divided by throttle load. If the air-meter reads higher than the throttle based estimate of air and torque, then the method simply closes the throttle until the air-meter is satisfied.

Abstract: A system and method wherein a torque monitoring algorithm compares torque demand (i.e., driver-demanded torque computed primarily from acceleration pedal position), with two independent torque estimates (e.g., one estimated from throttle position and one estimated from mass airflow (MAF) to the intake manifold). If the maximum of the two actual torque estimates exceeds the driver-demanded torque, the monitoring algorithm logic intervenes in engine torque production (e.g., shuts off fuel to cylinders) and lights a service (wrench) light. In order to prevent, or minimize, unnecessary engine torque production intervention, reducing a torque demand signal to the throttle by a factor, such factor being a function of airflow meter load divided by throttle load.

Abstract: A fail-safe mechanism of an air induction control apparatus for automotive engines is provided which is designed to hold a throttle valve at a middle position when a valve actuator has failed to move the throttle valve. The fail-safe mechanism includes a middle position hold stopper, an opener lever connected to the throttle shaft, and a first and a second coil spring. The first coil spring works to exert a first spring pressure on the opener member in a first rotational direction in which the throttle valve is rotated from a fully opened position to the middle position. The first coil spring is urged at an end thereof into constant engagement with the middle position hold stopper to hold the opener member from rotating in a second rotational direction opposite the first rotational direction. The second coil spring has a first and a second end between which the opener member extends. The first end abuts against the middle position hold stopper.

Abstract: There is provided a throttle control system and method for an internal combustion engine as well as an engine control unit, which are capable of controlling a throttle valve without any trouble even when the throttle valve is frozen. The throttle control system controls the degree of opening of the throttle valve. The opening of the throttle valve detected during control of the throttle valve to a fully-closed position at a start of the engine is set to a smallest angle. A temperature of the throttle valve is detected. A lower limit value of the target degree of opening is set to a degree of opening larger than the detected smallest angle of the throttle valve, when the detected smallest angle is larger than a predetermined degree of opening and at the same time the detected temperature of the throttle valve is lower than a predetermined temperature.

Abstract: A control system of an internal combustion engine includes a timing changing unit that changes opening and closing timing of an intake valve relative to rotation of an output shaft of the engine, a working angle changing unit that changes a working angle of the intake valve, a throttle mechanism including a throttle valve provided in an intake passage of the engine and an actuator that is operable to open and close the throttle valve, and an intake air quantity control unit that controls the timing changing unit, the working angle changing unit and the throttle mechanism so as to control an intake air quantity of the engine to a target intake air quantity. The control system detects a failure of at least one of the timing changing unit, the working angle changing unit and the throttle mechanism, and, upon detection of a failure, executes a selected one of difference fail-safe control processes corresponding to different forms of failures, depending upon the form of the detected failure.

Abstract: A pressing device for an apparatus for imparting a friction resistance to a rotary shaft driving an engine-output control device directly or indirectly to apply a resistance to an operation of an accelerator. The pressing device is a molded product made of a resinous material whose flexural strength is 50 MPa or higher and flexural modulus of elasticity is 3,300 MPa or higher. When a friction plate is formed compositely with a plate-shaped member to form the pressing device, friction plate is formed of a fluorocarbon resin; and at least one ingredient selected from a whisker whose Mohs hardness is 5 or less, a carbon fiber, and a hard resinous powder.

Abstract: A failure diagnosis apparatus for a throttle valve actuating device is disclosed. The throttle valve actuating device has an actuator for actuating a throttle valve provided in an intake system of an internal combustion engine and biasing elements for biasing the throttle valve to a predetermined retention opening. A feedback control of the throttle valve is performed so that an opening of the throttle valve coincides with a first predetermined opening. After the throttle valve is controlled to the first predetermined opening, a feedback control of the throttle valve is performed so that an opening of the throttle valve coincides with a second predetermined opening. It is determined that the throttle valve actuating device has failed when the time period during which the opening of the throttle valve remains in a predetermined determination range including the second predetermined opening, is shorter than a predetermined time period when performing the feedback control to the second predetermined opening.

Abstract: An electronic enhanced mobility control interface of a mobility enhancement system implemented in a motor vehicle having a conventional electronic throttle control system. The electronic enhanced mobility throttle interface includes an auxiliary electronic throttle sensor in duplication of the conventional throttle pedal electronic throttle sensor, wherein the driver's selection of either the auxiliary or throttle pedal position throttle sensor is interfaced transparently to an engine electronic controller, as for example an engine control module (ECM/PCM) for processing to the electronic throttle control (ETC) subsystem. The electronic mobility enhancement throttle interface further includes an auxiliary throttle control by which the driver executes throttle commands to the auxiliary electronic throttle sensor, a data switch for connecting one or the other of the throttle pedal position and auxiliary electronic throttle sensors processing electronics to the ECM/PCM.

Abstract: In order to provide an internal combustion engine control unit for a jet propulsion type watercraft which can control an internal combustion engine so that a rider can perform risk avoidance safely, a throttle open degree detector 22 which detects a state of the throttle operated by a rider, and a controller 300 which, when the throttle open degree detected by the throttle open degree detector 22 is a predetermined value or lower, keeps the rotation speed of the internal combustion engine 2 at a predetermined value for a predetermined period of time after the throttle open degree has reached the predetermined value or lower, are provided.

Abstract: In an engine controller with a feed back control system, an instruction signal for controlling an engine condition adjusting device is determined on the basis of a comparison between an input signal corresponding to a desired engine condition and an actual engine condition signal when the engine controller, the engine condition adjusting device and a sensor for generating the actual engine condition signal operates normally, and is determined on the basis of the input signal while preventing the instruction signal from being determined on the basis of the comparison between the input signal and the actual engine condition signal when an abnormality of at least one of the engine controller, the engine condition adjusting device and the sensor is detected.

Abstract: The invention relates to a device for adjustably limiting the maximum speed of an engine powered hand tool controlled by a power-regulating device (11) located in the handle of the tool. The device makes it possible to optimise the speed of the engine for the job that is to be done. The device consists of a threaded shaft (15) that is moved by rotating a nut (12) and a spring (14). When a higher speed than the selected level is required, is it possible to increase the speed to the maximum speed available by pressing the power-regulating device (11) with a force that exceeds the force from the spring (14).

Abstract: Methods and apparatus are provided for adjusting a throttle of a vehicle engine. The apparatus comprises an input sensor configured to provide an input signal having a value that approximately corresponds to an operating level of the vehicle engine requested by an operator and a memory configured to store a maximum input value for the input sensor. The maximum input value provides the value of the input signal that approximately corresponds to a maximum operating level of the vehicle engine. The apparatus is further configured to receive the input signal and access the memory to retrieve the maximum input value and further configured to update the maximum input value with the value of the input signal if the value of the input signal is greater than the maximum input value.

Abstract: An on-vehicle engine control apparatus carries out engine drive control and throttle control using one single CPU and improves safety. The apparatus includes a load relay for feeding a power to a motor that controls throttle valve opening, a first IC (integrated circuit element) containing a CPU, and a second IC connected to the first IC via serial interfaces. The apparatus further includes a first mutual diagnostic device incorporated in the first IC and diagnoses operation of the second IC, a second mutual diagnostic device incorporated in the second IC to diagnoses operation of the first IC, and a detector for detecting an abnormality in operation of each system involved in throttle valve control. Operation of the load relay is controlled based on diagnostic results and abnormality detection results of the first and second mutual diagnostic devices.

Abstract: An engine control unit, and method of use, uses a power curve or algorithm to pro-actively adjust fuel flow rate to an engine, optionally in combination with a reactive power curve or algorithm, thereby to adjust engine power, in anticipation of changes in loads being imposed on the engine, as well as to respond to engine speed changes. The ECU has a power curve or algorithm stored in memory which responds to certain predetermined operating conditions other than sensed engine speed, by providing a sequence of pro-active change inputs, at predetermined rates of change, in rate of delivery of fuel to the engine combustion chambers, independent of engine speed change, thereby to produce pro-active incremental changes in power output of the engine. Such pro-active incremental power changes are effected in anticipation of changes in load demand on the engine, and correspond generally with expected incrementally progressive changes in load demand on the engine.

Abstract: A closed throttle position of a vehicle internal combustion engine is determined by storing a plurality of signal values representative of previous foot-off position values of an accelerator pedal (10) within a normal range of pedal positions, determining a current foot-off position value of the accelerator pedal, comparing the current foot-off position value to an average of the previous stored foot-off position values, and using the average as the closed pedal position to determine a closed throttle position when the comparison is indicative of an abnormal pedal position.

Abstract: A fail-safe device includes an intake air amount sensor, a throttle position sensor for detecting a throttle opening degree of an electronic throttle controller, an accelerator position sensor for detecting an accelerator opening degree as an amount of pressing down on an accelerator, an intake air amount control unit for controlling the intake air amount to the engine, a target air-fuel ratio control unit for controlling a fuel injection amount to be supplied to the engine, a target ignition timing control unit for controlling ignition timing of air-fuel mixture inside a cylinder of the engine; and an electronic throttle control system abnormality warning unit for deciding, when a first requirement and a second requirement are satisfied based on the output of each sensor, that the electronic throttle controller is in failure, and for, prior to warning of the abnormality of the electronic throttle controller, controlling each of the control units.

Abstract: A fail-safe mechanism of an air induction control apparatus for automotive engines is provided which is designed to hold a throttle valve at a middle position when a valve actuator has failed to move the throttle valve. The fail-safe mechanism includes a middle position hold stopper, an opener lever connected to the throttle shaft, and a first and a second coil spring. The first coil spring works to exert a first spring pressure on the opener member in a first rotational direction in which the throttle valve is rotated from a fully opened position to the middle position. The first coil spring is urged at an end thereof into constant engagement with the middle position hold stopper to hold the opener member from rotating in a second rotational direction opposite the first rotational direction. The second coil spring has a first and a second end between which the opener member extends. The first end abuts against the middle position hold stopper.

Abstract: A method and system for controlling EGR rate of an internal combustion engine. The engine has an intake throttle for controlling mass flow to an intake of the engine and an EGR valve for controlling flow from the exhaust of the engine back to the intake of the engine along with air passing through the intake throttle. The method includes measuring a mass air flow passing to the intake throttle and a desired mass air flow. An error signal is produced representative of a difference between the measure mass air flow and the desired mass air flow. A pair of control signals is produced in response to such produced error signal. One of the pair of control signals is used to adjust the intake throttle to control mass air flow through such intake throttle. The other one of the pair of control signals is used to adjust EGR flow through the EGR valve. The pair of control signals operate the intake throttle and the EGR valve to drive the error signal towards a null.

Abstract: A fail-safe device includes an intake air amount sensor, a throttle position sensor for detecting a throttle opening degree of an electronic throttle controller, an accelerator position sensor for detecting an accelerator opening degree as an amount of pressing down on an accelerator, an intake air amount control unit for controlling the intake air amount to the engine, a target air-fuel ratio control unit for controlling a fuel injection amount to be supplied to the engine, a target ignition timing control unit for controlling ignition timing of air-fuel mixture inside a cylinder of the engine; and an electronic throttle control system abnormality warning unit for deciding, when a first requirement and a second requirement are satisfied based on the output of each sensor, that the electronic throttle controller is in failure, and for, prior to warning of the abnormality of the electronic throttle controller, controlling each of the control units.

Abstract: A returning spring 7 of the electronic control throttle and a default spring 8 for securing an initial opening degree (default opening degree) of the throttle valve 3 have diameters different from each other, and both of the springs 7, 8 are held around a shaft of the throttle valve shaft 3 and arranged between a gear 43 attached to the throttle valve shaft 3 and a wall portion of the throttle body 100. A shaft supporting gap of the throttle valve shaft 3 is filled with an air leak preventing material, and a minimum opening degree on control purpose of the throttle valve is set to a value larger than an amount of overshoot of the throttle valve occurring when opening degree of the throttle valve is changed from a maximum opening degree on control purpose of the throttle valve to the minimum opening degree.