Koito Manufacturing Company, Ltd.

Takayuki Unno

Kazuki Takahashi

Hiroki Shibata

Toshihisa Hayami

Hideki Uchida

Makoto Izawa

Tomoaki Serizawa

A control circuit for automobile headlamps which emit light in variable color. The control circuit prevents left and right headlamps from emitting beams of light in different colors. Each headlamp includes a white light bulb, and a yellow globe is moved from a first position to a second position to cover the bulb when yellow light is selected, and the yellow globe is moved back to the first position when white light is selected. If the movement of the globe stops between the first and second positions, the control circuit generates a fault signal for turning off the headlamp associated with the fault, thus preventing the headlamps from emitting light of different colors. Alternatively, the control circuit can adjust the position of the globe for the headlamp without the fault to be in agreement with the position with the headlamp having the fault, such that both headlamps emit light of the same color.

Control circuit for automobile headlamps emitting light in variable color

A vehicle cornering headlamp system which can be applied to any type of vehicle without changing the correspondence to a radiation angle, and which enables the radiation angle to follow the return of driver's eyes when the vehicle exits a curved road. The angular velocity .omega..sub.new is calculated at the time of travelling on a curved road on the basis of the output from an angular velocity sensor and the vehicle speed v is measured on the basis of distance pulses from a distance sensor. The current angular velocity, .omega..sub.new, is divided by the vehicle speed v to calculate the reciprocal number of a revolution radius r, which is multiplied by a constant K, so as to obtain a target value .theta.s of the radiation angle. Then, on the basis of the difference between .omega..sub.old, the angular velocity detected at a previous time, and .omega..sub.new, it is determined that the vehicle is approaching an end of the curved road when the gradient of the angular velocity .omega. changes toward the direction of zero. If an end of the curved road is detected, a target value .theta.s is set to half the target value .theta.s set when the vehicle is travelling on a curved road.

Vehicle cornering lamp system

A vehicular cornering lamp system which can be adapted to all types and models of vehicles without having to change the correspondence of the illuminating angle with specific characteristics of the vehicle. The angular velocity of the vehicle is detected when the vehicle is traveling on a curve by an angular velocity sensor. Pulses from a distance sensor are counted to detect the vehicle's velocity. Angular velocity data and vehicle velocity data are latched by respective latch circuits. The reciprocal of the turning radius is calculated directly by dividing the angular velocity data by the vehicle velocity data in a divider. There is carried out an arithmetic operation of calculating the reciprocal of the turning radius after calculating the turning radius by dividing the vehicle velocity data by the angular velocity data. The illuminating angle can be approximated as a simple inverse function with respect to the turning radius. The target position of the illuminating angle is calculated as an inverse function with respect to the turning radius so that the illuminating angle of headlamp is controlled so as to be coincident with the target position.

Growing community of inventors

Shizuoka, Japan

Takayuki Unno