GB1395621A - Regulated ingition system - Google Patents

Abstract

1395621 Ignition systems R C A CORPORATION 6 July 1972 [8 July 1971] 31590/72 Heading F1B With the ignition points 135 closed base current is provided to the transistor 125. Since no current is flowing initially in the circuit the potential across resistor 130 is zero and base current is also provided to the transistor 115 via the detection circuit 160. Accordingly both transistors are switched into saturation and current beings to flow through the series circuit comprising the D.C. source 111 transistor 115 winding 119 transistor 125 and resistor 130. As the current through the coil builds up the potential across the resistor 130 increases and when it attains a predetermined level the detection circuit 160 responds by cutting off the supply of base current to the transistor 115 causing it to turn off. With the transistor 115 off and the transistor 125 on (i.e. the ignition points still closed) the energy stored in the primary winding 119 sustains current flow through the series circuit including winding 119, transistor 125, resistor 130 and diode 150 when the current decreases sufficiently the drop in potential across the resistor 130 is detected by the detection circuit 160 which responds by providing base current to the transistor 115 causing it to turn on and recharge the coil to its desired energy level. When the ignition points 135 open base current is removed from the transistor 125 causing it to turn off at which point the energy stored in the winding 119 induces a high voltage in the secondary winding 121 which in turn provides the necessary ignition spark to the sparking plugs via the distributor.