Abstract: An apparatus for automatically adjusting a direction of a headlight of a vehicle includes a steered angle sensor detecting a steered angle of a steering wheel of a vehicle, a vehicle speed sensor detecting a speed of the vehicle, a control unit performing a swivel control by which the direction of the light axis of the headlight is adjusted to a target direction depending on the steered angle and the vehicle speed, and a variance calculating device calculating a variance of the steered angle detected by the steered angle sensor. The control unit halts the swivel control unit when the variance calculated by the variance calculating device exceeds a predetermined threshold.

Abstract: An apparatus for automatically adjusting a direction of a headlight of a vehicle includes a steered angle sensor detecting a steered angle of a steering wheel of a vehicle, a vehicle speed sensor detecting a speed of the vehicle, a control unit performing a swivel control by which the direction of the light axis of the headlight is adjusted to a target direction depending on the steered angle and the vehicle speed, and a variance calculating device calculating a variance of the steered angle detected by the steered angle sensor. The control unit halts the swivel control unit when the variance calculated by the variance calculating device exceeds a predetermined threshold.

Abstract: A lamp's optical axis control system for a vehicle includes vehicle speed sensor, steering angle sensor, a circuit for calculating driver's viewpoint and a controller for controlling the optical axis according to the position of the driver's view point. The controller indicates the position of the driver's viewpoint a certain time in advance according to the vehicle speed signal and the steering angle signal. Therefore, the illumination range of the headlamps can timely provides a desirable driver's view point.

Abstract: A lamp's optical axis control system for a vehicle includes vehicle speed sensor, steering angle sensor, a circuit for calculating driver's viewpoint and a controller for controlling the optical axis according to the position of the driver's view point. The controller indicates the position of the driver's viewpoint a certain time in advance according to the vehicle speed signal and the steering angle signal. Therefore, the illumination range of the headlamps can timely provides a desirable driver's view point.

Abstract: An ignition timing adjusting system for an internal combustion engine wherein the output of a magneto-type generator driven by the engine is used as a power source to generate a constant voltage output through a voltage regulator circuit, and a rotational angular position of the engine is detected by a sensor and the corresponding output signal being used as a reference signal in order to electronically determine an ignition timing by an advance angle computing circuit energized by the constant voltage output of the voltage regulator circuit, and further detecting the constant voltage output of the regulator circuit, and an advance angle adjusting circuit cancels the computed output from the advance angle adjusting circuit when the detected voltage is less than a voltage which is an absolute minimum voltage necessary for the accurate ignition timing operation, whereby when the detected constant voltage output is not adequately regulated the computed output of the advance angle adjusting circuit causing the ex

Abstract: An air flow amount adjusting system produces an air-fuel mixture of a desirable air-fuel ratio by controlling the direction of movement of a bypass valve mounted in an additional air supply pipe adapted to supply additional air into either the intake system or exhaust system of an internal combustion engine in accordance with an output signal produced from a gas sensor mounted in the exhaust system of the engine and indicative of the air-fuel ratio of the mixture supplied to the engine. A two-level mode signal whose threshold corresponds to the desired air-fuel ratio is produced in accordance with the output signal of the gas detector. After the two-level mode signal has changed from one level to the other level, the movement of the bypass valve is stopped for a certain period of time. If desired, the stopping period of the bypass valve may be changed in accordance with the temperature of the engine.

Abstract: An exhaust gas purifying apparatus having an exhaust pipe divided into at least two branches each connected to a different cylinder or cylinders. Each of the exhaust pipe branches is further connected to a secondary air supply tube to intermittently supply secondary air upstream of a three-way catalyst disposed in the branch thereby to vary periodically within a range the air-fuel ratio of exahust gases flowing into the three-way catalyst.

Abstract: An exhaust gas purifying system of the type utilizing a three-way catalyst containing an oxygen storage material includes an electronic control unit for controlling the amount of secondary air supplied to the exhaust system of an internal combustion engine. The electronic control unit receives a signal from an exhaust air-fuel ratio sensor indicative of an air-fuel ratio of the exhaust gases and provides a pulse signal to an electromagnetic valve disposed in the passage of the secondary air leading to the upstream of the three-way catalyst. The amount of secondary air supplied to the exhaust system is controlled such that the resultant exhaust gases having an exhaust air-fuel ratio greater than the stoichiometric ratio and those having an exhaust air-fuel ratio smaller than the stoichiometric ratio are alternately supplied to the three-way catalyst thereby to achieve the average exhaust air-fuel ratio to fall within the optimum purifying conditions of the three-way catalyst.

Abstract: A method of operating a three-way catalyst which contains an oxygen storage material and which is mounted on the exhaust system of an internal combustion engine is disclosed. In order to operate the three-way catalyst effectively, the air-fuel ratio of the mixture supplied to the engine is set to be richer than the stoichiometric ratio, and secondary air is intermittently supplied by an air pump into the exhaust system upstream of the three-way catalyst, thereby to alternately vary the air-fuel ratio of the exhaust gases supplied to the three-way catalyst to become rich and lean with respect to the stoichiometric ratio.

Abstract: An air flow amount adjusting system produces an air-fuel mixture of a desirable air-fuel ratio by controlling the direction of movement of a bypass valve mounted in an additional air supply pipe adapted to supply additional air into either the intake system or exhaust system of an internal combustion engine in accordance with an output signal produced from a gas sensor mounted in the exhaust system of the engine and indicative of the air-fuel ratio of the mixture supplied to the engine. A two-level mode signal whose threshold corresponds to the desired air-fuel ratio is produced in accordance with the output signal of the gas detector. After the two-level mode signal has changed from one level to the other level, the movement of the bypass valve is stopped for a certain period of time. If desired, the stopping period of the bypass valve may be changed in accordance with the temperature of the engine.

Abstract: An apparatus for detecting a deteriorated condition of an oxygen concentration sensor mounted in an exhaust pipe for an internal combustion engine for controlling an air-fuel ratio is described. The apparatus includes, in addition to the sensor, a reference oxygen concentration sensor mounted in the exhaust pipe downstream of a cleaning device, and a discrimination unit for determining the deterioration of the oxygen concentration sensor for controlling the air-fuel ratio by measuring at least one of a duty factor and a period of an output signal from the reference oxygen concentration sensor.

Abstract: Additional air is supplied through an additional air passage having a bypass valve into the main air passage of an internal combustion engine downstream of the throttle valve, and the amount of the additional air is controlled in accordance with the opening of the bypass valve. The direction of rotation of a bypass valve driving pulse motor is controlled in accordance with the output signal of an air-fuel mixture ratio sensor mounted in the exhaust system of the engine. Also the rotational speed of the pulse motor is varied in accordance with the operating conditions of the engine during warm-up operation.

Abstract: An additional air supply system for adjusting the air-fuel ratio of a mixture includes the improved control unit for actuating, at two different speeds, a drive motor of a bypass valve disposed in an additional air supply path. The control unit is provided with an air-fuel ratio discriminating circuit for generating high and low level signals by comparing a detected air-fuel ratio with the stoichiometric ratio, and an actuating circuit for producing pulse signals at each instant of inversion of the signal levels of the air-fuel ratio discriminating circuit in such that for a predetermined period from the instant of inversion a high frequency pulse signal is produced and then a low frequency pulse signal is produced for the remaining period until the next inversion.

Abstract: An apparatus for controlling the air-fuel ratio of an air-fuel mixture to be supplied into a combustion chamber of an internal combustion engine comprises a passage bypassing a carburetor and a throttle valve of the engine for supplying an additional air into the engine intake duct downstream of the throttle valve to dilute the air-fuel mixture to an air-fuel ratio most suited for the engine operation. An air valve is provided in the bypass passage to vary the air-flow cross-sectional area of the passage. The opening of the air valve is controlled mainly in accordance with the air-fuel ratio of the mixture as detected by an air-fuel ratio detector in the path of flow of engine exhaust gases. A variable orifice is provided in the bypass passage downstream of the air valve and defined by a valve seat and a needle valve operatively associated therewith to vary the opening area of the orifice.

Abstract: In an air flow control system including a gas sensor for detecting the concentration of a constituent of the exhaust gases from an internal combustion engine, an air passage for supplying additional air into the intake system or exhaust system of the engine, a by-pass valve for varying the passage area of the additional air passage, and means for controlling the opening and closing of the by-pass valve in accordance with the detection signal from the gas sensor whereby the amount of additional air supplied into the intake system or exhaust system of the engine is controlled in accordance with the concentration of the constituent of the exhaust gases, there is further provided an acceleration/deceleration sensor for detecting acceleration or deceleration of the engine, whereby when a transition from the acceleration or deceleration operating condition to the steady-state operating condition is detected, the opening and closing control of the by-pass valve is accomplished in such a manner that the amount of ope

Abstract: An air-fuel ratio controlling system for an internal combustion engine including a control circuit for controlling, in accordance with a detected air-fuel ratio, the operation of a drive motor of a control valve mounted in an additional air supply passage. The control circuit includes a timing pulse generator for generating timing pulses synchronized with a running speed of the engine and thus the control valve is intermittently rotated by a predetermined amount in response to the timing pulses. By increasing the frequency of the timing pulses during the periods of rapid acceleration and deceleration, a response to the change in the engine speed is further improved.

Abstract: An additional air supply control apparatus for an internal combustion engine including a bypass passage for supplying air additionally to the engine and a control valve provided in the bypass passage for controlling the amount of air-flow through the bypass passage. A gas sensor is mounted in an exhaust system of the engine for detecting changes in the air-fuel ratio and a control unit produces an intermittent control signal in accordance with a detection signal from the gas sensor. The control valve is driven by the control signal intermittently in a skip movement fashion.

Abstract: An overheat preventing system is provided for a vehicle exhaust gas purifier. The system comprises a temperature detector mounted in the locality of each of the exhaust ports of an engine, an overheat detector for detecting failure of an engine to fire from the temperature signals generated by the temperature detectors and for generating a signal, and an actuator for preventing the overheating of an exhaust gas purifier which is adapted to be operated upon the generation of the overheat signal from the overheat detector, whereby unburned gases are prevented from flowing into the exhaust gas purifier.

Abstract: An air-fuel ratio adjusting apparatus for an internal combustion engine employing a gas sensor whose electric characteristic changes rapidly at near the stoichiometric air-fuel ratio so as to maintain the air-fuel ratio of mixture at any desired air-fuel ratio other than the stoichiometric one. A bypass valve is mounted in a bypass passage for supplying additional air to the portion of the carburetor downstream of its throttle valve. In response to the sensed signal from the gas sensor mounted in the exhaust pipe, the bypass valve is opened or closed to increase or decrease the amount of additional air.

Abstract: A deteriorated condition detecting apparatus for an oxygen concentration sensor used in an air-fuel ratio feedback control for an internal combustion engine comprises a reference oxygen concentration sensor mounted in proximity to the oxygen concentration sensor used for the air-fuel ratio feedback control and a discriminator for comparing duty factors of output signals from those two sensors to determine a deteriorated condition of the oxygen sensor. The discriminator determines the deteriorated condition when the duty factor of the sensor under test deviates from the duty factor of the output signal of the reference sensor by a predetermined amount.