초록 ▼

A vehicle multiplex system includes a controller and a number of remote stations connected to the controller by a control bus. The controller receives multiplexed signals indicative of the desired operation of loads such as headlamps and motors. In order to obtain reduced intensity headlamp operatio

A vehicle multiplex system includes a controller and a number of remote stations connected to the controller by a control bus. The controller receives multiplexed signals indicative of the desired operation of loads such as headlamps and motors. In order to obtain reduced intensity headlamp operation or reduced speed of a continuous DC motor, the controller automatically connects and disconnects the headlamp or motor and a DC power source with a selected duty cycle. The period of repetition is sufficiently small to prevent perceptible flicker or fluctuation in motor speed. In this way, headlamp intensity and motor speed can be varied as desired, without increasing the hardware requirements of the system.

대표청구항 ▼

In a vehicle headlamp control system in a vehicle of the type comprising a headlamp; an electrical power source; means for generating a headlamp on signal; means for selectively interconnecting the headlamp and the power source with a low resistance current path and disconnecting the headlamp and th

In a vehicle headlamp control system in a vehicle of the type comprising a headlamp; an electrical power source; means for generating a headlamp on signal; means for selectively interconnecting the headlamp and the power source with a low resistance current path and disconnecting the headlamp and the power source; a multiplex system comprising: a data bus; a clock bus; a controller comprising clock means, coupled to the clock bus, for applying repeated sets of clock signals to the clock bus, means for reading data signals from the data bus, and means for applying data signals to the data bus; a first remote station coupled to receive the headlamp on signal and connected to the clock and data buses, said first remote station comprising means for counting the clock pulses in each set and for enabling the first remote station during a first selected subset of the clock pulses, and means for applying a first multiplexed signal, indicative of the state of the headlamp on signal, to the data bus when the first remote station is enabled; a second remote station connected to the clock and data buses, said second remote station comprising means for counting the clock pulses in each set and for enabling the second remote station during a second selected subset of clock pulses, means for reading a second multiplexed signal from the data bus when the second remote station is enabled, and means for controlling the interconnecting means in response to the state of the second multiplexed signal; the improvement comprising: first means, included in the controller, for selectively generating said second multiplexed signal in a first state, which causes the second remote station to control the interconnecting means to interconnect the headlamp and the power source, and a second state, which causes the second remote station to control the interconnecting means to disconnect the headlamp and the power source; means, included in the first means, for automatically cycling the second multiplexed signal between the first and second states at a first duty cycle during selected periods characterized by the absence of the headlamp on signal in order to illuminate the headlamp at reduced intensity; means, included in the first means, for automatically placing the second multiplexed signal in the first state with a second duty cycle higher than the first duty cycle during selected periods characterized by the presence of the headlamp on signal in order to illuminate the headlamp at increased intensity.