Abstract: An alarm system for a vehicle driver to prevent from dozing at wheel. The system includes structure for detecting drowsiness of the driver on a basis of abnormal steering change repetitions for a fixed period of time in a monotonous driving state defined, for example, as the transmission gear position being maintained at an overdrive or top position. The alarm system produces an alarm to the driver to prevent the driver from increasing the state of drowsiness.

Abstract: An alarm device is adapted to detect accumulation of fatigue of an automotive vehicle driver and to set an alarm time clock to produce an alarm. The detection of accumulation of fatigue is based on selected driving conditions of the vehicle and the period of time during which the detected driving condition is maintained. Fatigue data obtained based on the driving condition and the time is accumulated to determine a correction or updated value of the set time to be compared with the actual driving time. An alarm device will be activated when the driving time reaches the updated time.

Abstract: The driver of a speaker for an automotive audio system includes a plurality of magnetic coils wound around a common bobbin. Each of the magnetic coils is connected to one of a plurality of amplifiers each of which output an identical drive signal. By applying the common drive signal to each magnetic coil, the electromagnetic field created around the magnetic coil is enhanced approximately in proportion to the number of magnetic coils. Due to this increased electromagnetic force, a vehicle panel serving as a sound-amplifying medium can be satisfactorily and successfully driven so as to produce high-quality sound. The amplifiers are adapted to amplify the low-frequency components of the audio signal from a main amplifier.

Abstract: A drowsiness alarm system for a vehicle detects the driver's increasing state of drowsiness on a basis of abnormal steering change repetitions for a fixed period of time in a monotonous driving state defined, for example, as the gear shift lever being placed at an overdrive or top position. The alarm system produces an alarm to the driver to prevent the driver from increasing the state of drowsiness.

Abstract: A drowsiness alarm system for a vehicle which gives an alarm to the vehicle driver when detecting a vehicle steering condition such as to indicate a state of drowsiness, thus preventing driving in an increasing state of drowsiness. The drowsiness alarm system, according to the present invention, comprises: (a) a steering angle detection circuit which outputs a first pulse whenever the vehicle driver turns the steering wheel in either of the clockwise and anticlockwise directions in excess of a predetermined angle; (b) a quick steering detection circuit which outputs a second pulse whenever the number of the first pulses reaches a predetermined number within a predetermined period of time; and (c) an alarm unit which gives an alarm in a predetermined form to the vehicle driver in response to the second pulse fed from the quick steering detection circuit.

Abstract: According to the present invention there is provided a drowsiness alarm system which comprises: (a) a steering angle pulse generation circuit which produces first and second angle pulses at respective output terminals whenever the steering wheel is rotated clockwise and counterclockwise, respectively, through an angle equal to a predetermined angular increment; (b) curved road detection circuit responsive to the first and second steering pulses which counts the number of the first and second steering pulses separately and detects whether the vehicle travels on a curved road depending on whether the counted number of either of the first and second steering pulses reaches a first predetermined number within a predetermined period of time or depending on whether the difference of the counted number between the first and second steering angle pulses reaches a second predetermined number within the predetermined period of time; (c) a first counting circuit which counts the number of the first and second steering a

Abstract: A safety assurance system is disclosed for use in road vehicles. The system comprises a generator for providing a warning signal in response to a predetermined condition such as dozing of the driver. A rest signal is generated when the road vehicle is at rest, and a reset switch enables the driver to manually provide a reset signal. A first alarm signal is provided which is generated in response to the warning signal until the rest signal is generated. Also provided is a second signal which is generated in response to the warning signal until the rest signal or reset signal is generated. Thus, warning signals are generated that are terminated automatically when the vehicle comes to a stop or are terminated by manual operation of a reset signal.

Abstract: A device for detecting steering angle and steering direction of a steering wheel in an automotive vehicle, includes a pair of fixed contacts and a movable contact. The movable contact is arranged in connection with the fixed contacts in such a way that, when the steering wheel rotates in one direction, the movable contact engages only the first fixed contact, and when the steering wheel rotates in the opposite direction, the movable contact engages only the second fixed contact. Upon the basis of signals produced whenever the movable contact contacts one of the fixed contacts, the steering angle and steering direction are detected.

Abstract: A driving assurance system for an automotive vehicle includes a steering detector which generates an electrical pulse in response to each angular movement of the steering wheel exceeding an arcuate extent less than 10.degree.. A monostable multivibrator is connected to the steering detector to generate an output pulse in response to the first one of such pulses generated by a single steering operation so that the output from the miltivibrator may represent a single steering operation. The output from the multivibrator is counted for a predetermined period to determine the state of the driver to operate a warning signal when he becomes incapacitated.

Abstract: A pressure regulating valve varies an input fluid pressure from a pump to a steering pressure either stepwise or continuously varied in accordance with the vehicle speed and, when a power cylinder control valve alternatively admits the steering pressure into two working chambers of a power cylinder, a reaction chamber control valve alternatively admits the input fluid pressure into only a reaction force chamber of the power cylinder control valve, corresponding to the working chamber fed with the steering pressure, to produce in the reaction force chamber a reaction force increased with increases in the vehicle speed.

Abstract: A driving assurance system for an automotive vehicle includes a steering detector which generates an electrical pulse in response to each angular movement of the steering wheel exceeding an arcuate extent less than 10.degree.. A monostable multivibrator is connected to the steering detector to generate an output pulse in response to the first one of such pulses generated by a single steering operation so that the output from the multivibrator may represent a single steering operation. The output from the multivibrator is counted for a predetermined period to determine the state of the driver to operate a warning signal when he becomes incapacitated.

Abstract: A warning device is energized when speed signals integrated in an integrator exceed a predetermined level. However if a steering wheel and/or an accelerator pedal is operated, the integrator is reset.

Abstract: Steering wheel oscillations are detected and a first signal generated for each predetermined number of oscillations. A ramp generator is reset by each first signal and, if its output reaches a preset value, a comparator generates a second signal to indicate excessive time between first signals. An up-down counter is counted up by each first signal and down by each second signal. A comparator compares the contents of the counter with a present number and generates a third signal when the number in the counter falls below the present number. A timer consisting of an integrator and comparator generates a forth signal when the third signal has been present for a predetermined time. The forth signal causes an alarm device to alert the driver.

Abstract: First and second up-down counters are provided to operate in response to the steering movements of a motor vehicle. The first up-down counter operates as an up-counter while the steering wheel is rotated clockwise to increase its count by unit steps and operates as a down-counter while the steering wheel is rotated counterclockwise decreasing the count by unit steps to zero. The second up-down counter operates as an up-counter while the steering wheel is rotated counterclockwise and as a down-counter while the steering wheel is rotated clockwise. The content of each counter represents the relative angular displacement of the steering wheel. When a predetermined count is reached in each of the counters, an output is provided to indicate that the steering wheel has rotated a predetermined relative amount of angular displacement and the counters are cleared for subsequent counting operations.

Abstract: A constant voltage developed by a constant voltage generator is integrated, and the integrated voltage is applied to a voltage comparator. A standard voltage is applied to a voltage controller, which includes a sensor responsive to vehicle operating conditions, to control the level of the standard voltage to indicate the degree of driver alertness necessitated by the vehicle operatingconditions. The controlled standard voltage is also applied to the voltage comparator, and when the integrated voltage exceeds the controlled standard voltage the comparator develops a warning signal output. A warning device receives the warning signal and is thereby rendered operative in order to alert the driver.

Abstract: The steering movement of a motor vehicle is translated into an electrical signal which increases as the steering wheel rotates in one direction and decreases as the steering operation is reversed. This signal is applied to a minimum value detecting and storage circuit and a maximum value detecting and storage circuit, each including a storage capacitor, a switching diode for controlling the charge or discharge of the capacitor, and a bypass switching circuit connected across the diode. The diode of the minimum detector is connected such that it allows the capacitor to be discharged, while the diode of the maximum detector allows the capacitor to be charged. The bypass switching circuit of the minimum detector provides a charging path to the capacitor, while the bypass circuit of the maximum detector provides a discharging path to the capacitor. The voltages developed across the two capacitors are measured and compared with a reference voltage.