| 摘要 |
A flasher for vehicles wherein a transistor switching circuit is driven by the output from a transistor adapted to conduct upon closure of a flasher lamp change-over switch or all-lamp (hazard-warning) flasher switch, the output from said switching circuit energizing an exciting coil to close a normally-open contact, and flasher lamps are turned on with a lamp current conducted thereto through said normally-open contact, a resistor and said flasher lamp change-over switch or all-lamp (hazard-warning) flasher switch. The value of said lamp current is then detected by the voltage drop across said resistor which in turn provides a bias voltage between the base and emitter of said transistor, and a current conduction time limiting circuit is further provided for determining the duration of current supply to said flasher lamps by a charging time constant of two resistors and a capacitor such that the operation of said transistor switching circuit is discontinued by the output from said conduction time limiting circuit to de-energize the exciting coil and cause the flasher lamps to go off for a period of time which is determined by the discharging time constant of the one of the two resistors and capacitor in said conduction time limiting circuit. Thus, there is provided a flasher for vehicles wherein not only a direction indicating function, including an ability to indicate occurrence of burn-out or breakage (circuit discontinuity) of any one of the flasher lamps, but also a hazard-warning or fault indicating function are realized through a single flasher circuit in which integrated circuits may be readily utilized.
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