BATTERY CHARGER FOR TOWED VEHICLES AND THE LIKE

摘要

An electrically charging circuit for applying a controlled charge to a receiving device, such as a battery, and particularly such as a battery carried on a towed vehicle such as a trailer for actuating the trailer brakes during emergency situations s uch as unexpected disconnection from the towing vehicle, i.e., brake-away. In a basic s ense, the charging circuit includes a voltage potential-responsive element or componen t for sensing the charged level of the receiving device coupled to the circuit and ena bling or disabling the circuit charging operation, together with a variable-conductance c ircuit component for producing a generally constant charging voltage output to the rece iving device over a wide range of applied voltages but also operable to provide a firs t amount of current flow to the receiving device at a given applied voltage and temperatu re but a second a limited such current flow when the voltage differential across the char ging circuit is sufficiently large. In its most preferred embodiment, the voltage potential-responsive component may be a diode switch, and the variable-conductan ce circuit component may be a positive temperature coefficient (PTC) thermacouple.