Early activation device for vehicular brake warning lamps - is operated only by rapid closure of throttle in conjunction with urgent depression of clutch pedal

摘要

The lamps (4) are lit by a device (5) incorporating a potentiometer (6) pref. coupled mechanically to the throttle flap (2). The rate of closure is evaluated by a differentiating circuit (7) linked to a negative limit value comparator (8). A NAND gate (14) addressed from the clutch pedal (13) triggers a multivibrator (9) which energises a relay (10), closing the brake light switch (11). The clutch pedal connection excludes any false warning occasioned by an abnormally rapid release of the accelerator pedal (3). ADVANTAGE - Comparatively simple device gives very prompt warning after anxious or desperate braking e.g. in emergency situations.