Transistorized battery charger

Claim 1

A BATTERY CHARGER COMPRISING: A PAIR OF INPUT TERMINAL FOR RECEIVING A SOURCE OF POWER; FIRST AND SECOND RECTIFIER MEANS COUPLED TO SAID INPUT TERMINALS; VARIABLE VOLTAGE MEANS COUPLING SAID SECOND RECTIFIER MEANS TO SAID INPUT TERMINALS; FIRST AND SECOND OUTPUT TERMINALS ADAPTED TO BE CONNECTED TO A BATTERY TO BE CHARGED; VARIABLE IMPEDANCE MEANS CONNECTING THE OUTPUT CURRENT FROM SAID SECOND RECTIFIER MEANS TO SAID FIRST OUTPUT TERMINAL, SAID SECOND OUTPUT TERMINAL BEING CONNECTED THROUGH SAID SECOND RETIFIER MEANS TO ONE OF SAID INPUT TERMINALS, SAID VARIABLE IMPEDANCE MEANS HAVING A CONTROL ELECTRODE; CONSTANT VOLTAGE MEANS RESPONSIVE TO THE OUTPUT OF SAID FIRST RECTIFIER MEANS, SAID CONSTANT VOLTAGE MEANS BEING SELECTIVELY ADJUSTABLE TO PROVIDE DIFFERENT LEVELS OF CONSTANT VOLTAGE; AMPLIFIER MEANS HAVING AN INPUT CIRCUIT AND AN OUTPUT CIRCUIT, SAID INPUT CIRCUIT BEING CONNECTED BETWEEN SAID CONSTANT VOLTAGE MEANS AND SAID SECOND OUTPUT TERMINAL AND SAID OUTPUT CIRCUIT BEING CONNECTED BETWEEN SAID CONTROL ELECTRODE OF SID VARIABLE IMPEDANCE MEANS AND SAID SECOND OUTPUT TERMINAL SO THAT SAID AMPLIFIER MEANS IS RESPONSIVE TO THE DIFFERENCE BETWEEN SAID CONSTANT VOLTAGE AND THE VOLTAGE ACROSS SAID OUTPUT TERMINALS TO CONTROL THE IMPEDANCE OF SAID VARIABLE IMPEDANCE MEANS; WHEREBY, UPON THE ADJUSTMENT OF SAID VARIABLE VOLTAGE MEANS TO SUPPLY THE POTENTIAL REQUIERED BY THE BATTERY TO BE CHARGED AND THE SELECTION OF SAID CONSTANT VOLTAGE TO BE SLIGHTLY LESS THAN SAID BATTERY POTENTIAL, A BATTERY CONNECTED TO SAID OUTPUT TERMINAL WILL BE CHARGED UNTIL ITS POTENTIAL IS SUBSTANTIALLY EQUAL TO THE CONSTANT VOLTAGE SUPPLIED BY SID CONSTANT VOLTAGE MEANS.