Trafficators aresemaphore signals which, when operated, protrude from the bodywork of amotor vehicle to indicate its intention to turn in the direction indicated by the pointing signal. Trafficators are often located at the doorpillar.
They first appeared in the 1900s, when they were actuated either mechanically or pneumatically. In 1908, Alfredo Barrachini inRome added electric lights inside the arms that turned on as they extended, but operation was still by a cable system.[1] Electric operation came in 1918 when the Naillik Motor Signal Company ofBoston added electric motor drive. This system was superseded by twoFrench inventors, Gustave Deneef and Maurice Boisson, who used a linearsolenoid in 1923. The final complete system came in 1927 whenBerlin-based Max Ruhl and Ernst Neuman combined internal illumination and solenoid operation: (but seeGladstone Adams).
The shape of the trafficator arm is closely based upon the shape of thesemaphore signal arm used by theRoyal Bavarian State Railways beginning in 1890. The shape differs in that the trafficator has only the lower 'blade' of the rail signal's terminal 'arrowhead', so that the retracted trafficator sits flush with the vehicle's exterior.
They were common on vehicles until the introduction of the flashing amber, red or whiteindicators at or near the corners of the vehicle (and often along the sides as well), now referred to as "turn-signals". They have been increasingly rare since the 1950s, as ever-stricter legislation has prescribed the need for the modern type of flashing signal. Many historic vehicles (e.g. pre-1960Volkswagen Beetle) that are used on today's roads have had their trafficators supplemented or replaced with modern indicators to aid visibility and to meet legislative requirements. In some countries trafficators may now be retro-fitted with flashing lights.
