Koito Manufacturing Company, Ltd.

Kazuki Takahashi

Kiyoshi Wada

Hiroki Shibata

Keiichi Tajima

Takashi Kurita

Kiyoshi Yamashita

Toshihisa Hayami

Makoto Izawa

Takayuki Unno

Hideki Uchida

Hiromi Shibata

A headlamp apparatus for a vehicle accurately detects a straight steering position in a steering device of the vehicle, thereby controlling a light distribution characteristic of a headlamp of the vehicle. In a headlamp apparatus for a vehicle including a controller for controlling a light distribution of a headlamp based on a steering angle of a steering device of the vehicle, the controller detects a straight steering position based on an origin position signal obtained when each of wheel speeds SPDL and SPDR of left and right wheels (front wheelsLF andRF) of the vehicle is at least a reference value &#x3b1; and a difference in the speed is equal to or lower than a reference value &#x3b2; on the basis of an origin position signal PZ to be output from the steering device for each rotation of a steering wheel and the difference in the speed.

Headlamp apparatus for vehicle

An irradiation direction control apparatus for a vehicular lamp including: a vehicle state detection device for detecting a state of a vehicle; a drive device for directing irradiation light of a lamp toward a desired direction; and a compensation calculation device for performing a compensation calculation to keep the irradiation light of the lamp to a predetermined direction in accordance with a signal from the vehicle state detection device and sending a compensation signal to the drive device, whereby at the time of lighting the lamp or during lighting of the lamp, the compensation calculation device performs the compensation calculation to keep the irradiation light of the lamp to the predetermined direction in accordance with the signal from the vehicle state detection device and sends the compensation signal based on a calculation result to the drive device to drive the lamp or components thereof, whereas at the time of deactivating the lamp or during deactivation of the lamp and with a power source of the vehicle in operation or during running of the vehicle, the compensation calculation device performs only the compensation calculation to keep the irradiation light of the lamp to the predetermined direction in accordance with the signal from the vehicle state detection device and does not send the compensation signal to the drive device.

Irradiation direction control apparatus for vehicular lamp

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 method and an apparatus for determining a rotation center of a rotary body comprises a rotary body rotating in clockwise and counterclockwise directions in cooperation with the steering for a vehicle, and original position detecting circuit which detects a predetermined original angular position which the rotary body taken per each rotation, thus judging an original angular position taken when other original angular positions are not detected within a lapse of a predetermined time after the original angular position has been detected as rotation centers in the clockwise and counterclockwise directions of the rotary body.

Method and apparatus for determining a rotation center of a rotary body

A vehicle cornering headlamp system in which the direction of illumination of the headlamps of an automobile are made to follow the actual direction of movement of the vehicle, except that the direction of illumination is returned to the straight-ahead direction more quickly than it is moved away therefrom, thereby more accurately following the usual eye movement of the driver. For this purpose, a control signal is generated which has a pulse width indicative of the steering angle but which has a variation characteristic with respect to steering angle which is larger when the steering wheel is turned back towards the straight-ahead position than when the steering wheel is turned away from the straight-ahead position.

Vehicle cornering headlamp system

An automotive illumination system with which, when steering the vehicle around a curve or corner, both the path along which the vehicle is to travel and the direction straight ahead of the vehicle are sufficiently illuminated. Four headlamps are provided. Two of the headlamps, preferably the outer two, have directions of illumination fixed in the straight-ahead direction of the vehicle. The other two headlamps have directions of illumination which are controlled in accordance with the steering angle of the vehicle.

Automotive illumination system

In a vehicle cornering lamp system, a control signal having a pulse width corresponding to a steering angle is periodically produced, and the amount of position shift between the actual direction of illumination of the headlamps and the target direction of illumination determined from the steering angle is detected according to the control signal thus produced. An electric motor is driven to change the direction of illumination of the headlamps so that the amount of position shift becomes zero, that is, the direction of illumination of the headlamps is linearly changed with the electric motor while following the steering angle.

An apparatus for determining a rotation center of a rotary body comprises a rotary body rotating in clockwise and counterclockwise directions in cooperation with the steering for a vehicle, and original position detecting circuit which detects a predetermined original angular position which the rotary body taken per each rotation, thus judging an original angular position taken when other original angular positions are not detected within a lapse of a predetermined time after the original angular position has been detected as rotation centers in the clockwise and counterclockwise directions of the rotary body.

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Shizuoka, Japan

Kazuki Takahashi