Abstract: A distance measuring apparatus installed on a car for measuring the distance of the car from the one in front. The distance measuring apparatus comprises a laser generator for emitting a laser beam, a photosensor for receipt of the laser beam reflected from the car in front, means for calculating the distance between the cars when the photosensor receives the reflected laser beam, and a control unit for controlling an adjustable range of the emitted laser beam according to the calculated distance.

Abstract: An automatic braking system for a vehicle is provided. This system includes generally a speed sensor for monitoring speed of the vehicle and a distance sensor for monitoring a distance between the vehicle and the preceding vehicle. The system determines a marginal time required for the vehicle to collide with the preceding vehicle based on speed relative to the preceding vehicle and the distance to the preceding vehicle to automatically actuate a brake when the marginal time is shorter than a preselected marginal time.

Abstract: There is proved a driving force control system which comprises device for measuring operating state of the vehicle brake system and generating an output signal, and device for controlling a driving force upon a predetermined condition being fulfilled after the output signal has indicated a predetermined operating state of the vehicle brake system.

Abstract: A drowsiness alarm system and method for use in automotive vehicles is set to a stand-by state in response to a specific sequence of steering wheel maneuvers which may reflect driver drowsiness, for example, a relatively long period during which the steering wheel is not turned followed by an abrupt steering adjustment. From the standby state, an alarm or display alerting the driver will be generated in response to another sequence of steering maneuver confirming driver drowsiness. The second sequence of maneuvers may be selected from among a number of conventional steering behavior criteria. If driver drowsiness is not confirmed within a predetermined period of time after initiation of the stand-by state, the system is reset to its initial state.

Abstract: A system and method for detecting driver drowsiness in an automotive vehicle employs means for detecting changes in steering direction of a steering wheel on the basis of steering pulses, each steering pulse being produced whenever the steering wheel is rotated through a predetermined angle, and determines that the vehicle driver is drowsy when the number of steering pulses within a fixed interval of time exceeds a first reference value and the number of steering reversals within the fixed interval of time is below a second preset reference value.

Abstract: A fatigue alarm system and method for an automotive vehicle driver is adapted to measure periods of time during which the vehicle is driven and to subtract therefrom periods of time during which the driver rests. The driver rest periods are distinguished from brief stops of the vehicle in order to accurately measure the adjusted period of driving time. In order to distinguish rest periods from brief traffic stops, the duration of vehicle stops are measured and compared with a given value. When the vehicle stop periods are shorter than the given value, the vehicle is judged to be stopped briefly, i.e. that the driver is not resting, and the measured driving period is incremented by the measured vehicle stop period. On the other hand, when the stop periods are longer than the given value, the driver is judged to be resting. In this case, the measured stop time is subtracted from the measured driving time after being adjusted by a suitable proportionality factor.

Abstract: A drowsiness alarm system for a vehicle detects and signals that the vehicle driver is drowsy on the basis of the duration during which no steering adjustments are made and the magnitude and speed of abrupt steering adjustments immediately following the non-steering period. Parameters compared to the magnitude and speed of the abrupt steering adjustments in order to recognize steering behavior reflecting drowsiness are adjusted in accordance with the duration of the non-steering period.

Abstract: A system and method for detecting driver drowsiness on the basis of steering pulses, each steering pulse being produced whenever a steering wheel is rotated through a predetermined angle and indicating the direction of rotation of the steering wheel, comprising means for detecting the roughness of the road surface on which the vehicle is travelling and interrupting the detection of driver drowsiness for a fixed interval of time when the road surface roughness exceeds an acceptable level, i.e. a level conductive to accurate drowsiness detection.

Abstract: An internal combustion engine is disclosed which comprises first and second cylinder units each including at least one cylinder, a control circuit responsive to engine load for supplying a mixture of an optimum air/fuel ratio to the first and second cylinder units and for terminating the supply of the mixture to the second cylinder unit when the engine load is below a given value, and an exhaust system having therein a catalytic converter. An emergency circuit is provided for forcing the control circuit to lean out the air/fuel ratio in response to an increase in the temperature of the catalytic converter.

Abstract: A split engine control system operates a multiple cylinder internal combustion engine by using only some of the plurality of cylinders under light load conditions. The total number of cylinders are split into a first cylinder group which is always activated during engine operation and a second cylinder group which is deactivated under light load conditions. The engine is provided with an exhaust passage which consists of first and second upstream exhaust passages connected to the first and second cylinder group, respectively, and a common downstream exhaust passage. An exhaust gas sensor and a first catalytic converter are disposed in the first upstream exhaust passage, and a second catalytic converter is disposed in the common downstream exhaust passage. A temperature sensor is provided in the second catalytic converter.

Abstract: An internal combustion engine is disclosed which includes an active cylinder unit always active and an inactive cylinder unit being inactive when the engine load is below a predetermined value. The engine has an intake passage divided into first and second branches leading to the active and inactive cylinder units, respectively. The second intake passage branch is connected through an EGR passage to the exhaust passage of the engine. The second intake passage branch has therein a stop valve and the EGR passage having therein an EGR valve. Means are provided for closing the stop valve and opening the EGR valve at a predetermined time after a low engine load condition occurs.

Abstract: An internal combustion engine is disclosed which includes first and second cylinder units each having at least one cylinder, and a control unit responsive to engine load for rendering the first and second cylinder units active at high load conditions and rendering the second cylinder unit inactive when the engine load is below a predetermined value. A rapid acceleration detector is provided which is responsive to rapid engine acceleration for causing the control unit to render the first and second cylinder units active regardless of the engine load.

Abstract: Disclosed is a cylinder control system for a multicylinder internal combustion engine equipped with an exhaust gas purification device. This system has a valve control circuit which controls the number of fuel injection valves opened and closed, according to the load conditions of the engine. A detector is provided for determining the temperature in the exhaust gas purification device to generate a signal indicative of the temperature. A comparator compares the temperature signal with a reference value to generate, for the valve control circuit, a second signal indicative of whether the determined temperature is higher than a predetermined value. When the determined temperature is higher than the predetermined value, the second signal causes the valve control circuit to close the fuel injection valve or valves which thus far have been opened.

Abstract: An internal combustion engine is disclosed which comprises first and second cylinder units each including at least one cylinder, an induction passage divided downstream of the throttle valve into first and second intake passages leading to first and second cylinder units, respectively, a vacuum tank held at a vacuum above that in the induction passage downstream of the throttle valve, a stop valve provided at the entrance of the second intake passage and adapted to move toward its closed position when connected to the vacuum tank, and a control circuit adapted to block the supply of fuel to the second cylinder unit and connect the vacuum tank to the stop valve thereby shifting the engine operation into a split engine mode when the engine load is below a predetermined value.

Abstract: An internal combustion engine is disclosed which comprises first and second cylinder units each including at least one cylinder, a stop valve provided between the first and second cylinder units, an EGR passage for recirculating exhaust gases into the second cylinder unit, an EGR valve provided in the EGR passage, and control means for disabling the second cylinder unit when the engine load is below a given value. Means is provided to ensure that the EGR Valve opens after the stop valve closes when the engine load changes from its high condition to a low condition and to ensure that the stop valve opens just after the EGR valve closes when the engine load changes from its low condition to a high condition.

Abstract: An internal combustion engine is disclosed which includes first and second cylinder units, an intake manifold divided into first and second intake passages leading to the first and second cylinder units, respectively, an exhaust manifold divided into first and second exhaust passages leading from the first and second cylinder units, respectively, and control means for providing a control signal to disable the second cylinder unit when the engine load is below a predetermined value. The second intake passage has therein a first normally open valve adapted to close in response to the control signal. The second exhaust passage has therein a second normally open valve adapted to close in response to the control signal. Pressure control means is provided which is responsive to the control signal for supplying a predetermined pressure not less than atmospheric pressure to the second intake passage, thereby maintaining the second intake passage at the predetermined pressure.

Abstract: A fuel injection control system is disclosed for an internal combustion engine having fuel injectors. The system comprises fuel cut-off means operable for rendering some of the fuel injectors inoperative only when the engine speed exceeds a first predetermined value during engine deceleration and for rendering the remaining fuel injectors inoperative only when the engine speed exceeds a second predetermined value higher than the first predetermined value during engine deceleration. Control means is provided for increasing the second predetermined value when rapid engine deceleration occurs.

Abstract: An internal combustion engine is disclosed which includes active and inactive cylinders, an intake passage divided into first and second branches leading to the active and inactive cylinders, respectively, valve means provided at the entrance of the second intake passage, and fuel supply means for supplying a controlled amount of fuel into the active and inactive cylinders. A load detector is provided for detecting engine load to provide a low load indication signal to the fuel supply means which thereby cuts off the supply of fuel to the inactive cylinders and also to the valve means which thereby cuts off the flow of air to the inactive cylinders. Delay means is provided for delaying the start and end of application of the low load indication signal to the fuel supply means.

Abstract: A fuel injection control system is disclosed for an internal combustion engine having fuel injectors. The system comprises fuel-cut means operable for rendering some of the fuel injectors inoperative only when the engine speed exceeds a first predetermined value during engine deceleration and for rendering the remaining fuel injectors inoperative when the engine speed exceeds a second predetermined value higher than the first predetermined value during engine deceleration. Control means is provided for rendering the fuel-cut means inoperative when rapid engine deceleration occurs, thereby permitting the operation of all of the fuel injectors regardless of the engine speed.

Abstract: An internal combustion engine is disclosed which includes active cylinders which are always active and inactive cylinders which are inactive when the engine load is below a predetermined value. The engine has an intake passage divided into first and second branches connected to active and inactive cylinders, respectively. The second branch is provided near its inlet with a stop valve and is connected through an EGR passage to the engine exhaust passage. Means are provided to attenuate pressure waves resulting from exhaust pulsations and propagated through the EGR passage toward the second intake passage branch.