BE898037A - Electronic circuit for automatically switching vehicle lamps - uses photoresistance to detect light level and logic circuit to give hysteresis and has lay for engine starting - Google Patents

Abstract

The automatic lamp operation circuit is fitted to the existing lighting circuits of a motor vehicle. The circuit has three main elements; a photoresistance, a logic block, and switching relays. The photoresistance develops a voltage proportional to the level of incident illumination, and the logic circuit monitors the level of this voltage to determine whether the lamps should be illuminated or not. - If the external light level is low the logic circuit initiates switching of the lamps, but delays the switching for a period to allow starting of the motor with full battery power. A hysteresis circuit is included to prevent 'hunting' of the switch in marginal light conditions.(0/0)

Description

       

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  BREVET D'INVENTION DESCRIPTION CIRCUIT POUR ALLUMER ET ETEINDRE AUTOMATIQUEMENT
LES FEUX D'UN VEHICULE Ce circuit double, en la rendant automatique, la fonction de l'interrupteur principal des feux de position et des feux de 
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 croisement d'un vehicle. Quant aux feux de route, ceux-ci doivent etre actionnes comme d'habitude, par l'interrupteur du vehicle monte d'origine. 



  Il est connecte en serie dans les circuits   electriques   de commande des feux d'un vehicle. Un interrupteur est   prevu   dans ce circuit pour qu'il puisse   etre   deconnecte electriquement et la fonction de l'interrupteur d'origine du vehicle retable. Ce circuit se compose essentiellement : . d'une photoresistance . d'une partie"logique" . de deux relais La logique   interprete   un signal (une tension   electrique   variable en fonction de la lumiere incidente sur la photoresistance) et 

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 ING.   AN DREA MODIANO   actionne opportunement et simultanement les deux relais qui "allument"et"eteignent"les feux du vehicle. 



  La logique assure aussi un   delai   de quelques secondes, a partir du moment ou elle est mise sous tension, pendant lequel les feux resteront eteints,   meme   dans le noir. 



  Ceci afin d'assurer qu'au moment du demarrage du moteur, toute la puissance de la batterie soit   utilisee   a cette tache. 



  Enfin la logique tient compte d'une hysteresis necessaire pour eviter que les feux du vehicle ne s'allument et s'éteignent continuellement en condition de penombre. 



  Cette hysteresis est   reglable,   ainsi que les niveaux de sombre et de lumiere qui declanchent l'action du circuit, par deux potentiometres. 



  Deux voyant lumineux (L. E. D. ) indiquent respectivement la mise sous tension du circuit et la fontion de"feux allumes". 



  Le circuit est protege contre une inversion de polarite qui pourrait se produir lors du placement. 



  Le circuit est realise par le composants suivants :   . 1   circuit integre type 556 double timer   . 1   photoresistance   . 2 potentiometres   de   lOKohms   ou 15Kohms   . 2   LED   . 3   resitances   . 3   diodes   . 2   condensateurs au tantale   . 2   relais pour   cablage   direct sur circuit imprime   . 1   connecteur a 6 poles pour   cablage   direct sur circuit imprime   .

   1   interrupteur deviateur a 6 poles 

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   ING.   ANDREA MODIANO Le circuit est contenu dans un boitier en matiere plastique de dimensions   reduites   (environ 95x50xl8mm) qui s'applique de preference au coin interieur gauche du parebrise du vehicle, par l'intermediaire d'une bande autocollante a double face. 



   RESUME Ce circuit rend completement automatique le fonctionnement des feux d'un vehicle. 



  Il allume les feux d'un vehicle quand la luminosite exterieure est insuffisante. 



  Il assure un retard de quelques secondes avant que les feux du vehicle soient allumes, lors de la mise en marche du moteur dans le noir. 



  Il eteint les feux du vehicule dans deux cas : . quand la luminosite exterieure est suffisante . quand les clefs du contact sont disinserees.



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  PATENT OF INVENTION DESCRIPTION CIRCUIT FOR AUTOMATICALLY TURNING ON AND OFF
VEHICLE LIGHTS This circuit doubles, by making it automatic, the function of the main switch of the position lights and the
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 crossing of a vehicle. As for the main beam, these must be activated as usual, by the switch of the vehicle fitted as standard.



  It is connected in series in the electrical circuits controlling the lights of a vehicle. A switch is provided in this circuit so that it can be electrically disconnected and the function of the original switch of the vehicle retable. This circuit essentially consists of:. photoresistor. of a "logical" part. two relays The logic interprets a signal (a variable electrical voltage depending on the light incident on the photoresistor) and

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 ING. AN DREA MODIANO activates timely and simultaneously the two relays which "light" and "extinguish" the lights of the vehicle.



  The logic also ensures a delay of a few seconds, from the moment it is switched on, during which the lights will remain off, even in the dark.



  This is to ensure that when the engine is started, all of the battery power is used at this task.



  Finally the logic takes into account a hysteresis necessary to avoid that the lights of the vehicle do not come on and go out continuously in the dark.



  This hysteresis is adjustable, as well as the dark and light levels which trigger the action of the circuit, by two potentiometers.



  Two indicator lights (L. E. D.) indicate respectively that the circuit is energized and that the "igniting lights" function.



  The circuit is protected against a reverse polarity which could occur during placement.



  The circuit is made by the following components:. 1 integrated circuit type 556 double timer. 1 photoresistor. 2 potentiometers of OKohms or 15Kohms. 2 LEDs. 3 resitances. 3 diodes. 2 tantalum capacitors. 2 relays for direct wiring on the printed circuit. 1 connector with 6 poles for direct wiring on printed circuit.

   1 diverter switch with 6 poles

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   ING. ANDREA MODIANO The circuit is contained in a plastic case of reduced dimensions (approximately 95x50xl8mm) which preferably applies to the left interior corner of the vehicle windscreen, by means of a double-sided adhesive strip.



   SUMMARY This circuit makes the operation of a vehicle's lights completely automatic.



  It turns on the lights of a vehicle when the exterior brightness is insufficient.



  It provides a delay of a few seconds before the vehicle's lights are turned on, when the engine is started in the dark.



  It extinguishes the vehicle lights in two cases:. when the external luminosity is sufficient. when the ignition keys are disconnected.