Capacitor discharge ignition system

Claim 2

An ignition circuit for internal combustion engines and rotating turbine engines having a spark plug in each combustion chamber comprising a source of direct current, a charging circuit including converter means having an input connected to said current source and an output adapted to develop a relatively high DC potential, said converter being substantially devoid of parasitic oscillation on being short circuited, a storage capacitor connected to the converter output to be charged thereby, a discharge circuit including the capaciTor, a switching means, and an input winding of an output transformer, said transformer having a winding connected to said spark plugs, sensing means adapted to develop signals in response to the predetermined positioning of an engine part representative of the occurrence of a preselected portion of the engine cycle and control means adapted to actuate said switching means in response to a signal developed by said sensing means and discharge said discharge capacitor through said switching means and said output transformer winding to fire said spark plugs, wherein said control means includes electrical storage means adapted to transfer electrical energy to said switching means to actuate same in response to a signal from said sensing means and a feedback means connected between said output transformer and said electrical storage means adapted to feed a small portion of the electrical energy developed in said output transformer to said electrical storage means to substantially completely reverse charge same on discharge of the discharge capacitor thereby to prevent more than a single effective discharge in the discharge circuit during a single discharge cycle.

Claim 3

The circuit of claim 1 including delay means with unidirectional current means adapted to introduce a predetermined time delay before the electrical storage means of the control means can be recharged after a signal from the sensing means has been received and the electrical energy has been transferred.

Claim 4

An ignition circuit according to claim 1 wherein the charging circuit includes a converter having a variable repetition rate and being responsive to the application of a low impedance load thereto to interrupt operation and responsive upon removal of such load to resume operation.

Claim 5

The circuit of claim 1 wherein said switching means includes rectifier means having a cathode and a switching electrode forming triggers of opposite polarity, signal path means connecting both said cathode and said switching electrode to potentials of opposite polarity to apply a reverse gate voltage thereto in the absence of a developed signal from the sense means.

Claim 6

The circuit of claim 4 wherein the signal path means connected to said cathode further includes a unidirectional current means and a charge storage means, which storage means serves to reverse bias the rectifier means whenever the DC potential of the charging circuit falls below the potential of the charge storage means.

Claim 7

An ignition circuit for internal combustion engines and rotating turbine engines having a spark plug in each combustion chamber comprising: a source of direct current; a DC to DC converter connected thereto including a pair of transistors, transformer means coupling said transistors through the primary winding thereof to provide a variable frequency oscillator circuit including a portion of the transformer primary winding in the feedback circuit thereof, and rectifier means connected across the secondary winding of said transformer to rectify the output signals developed in the secondary winding of the converter transformer; an output transformer having a primary winding and an output winding; a storage capacitor serially connected across the output of said converter; switching means also connected across the output of the converter in parallel with said output transformer and said capacitor; control means adapted to actuate said switch means to provide a short circuit low impedance electrical path therethrough for the discharge of an electrical charge stored in the storage capacitor through the output transformer and at the same time by means of a reflected load from the secondary winding of the converter transformer to the primary winding thereof to effectively remove the drive to the transistor oscillators and momentarily interrupt the operation of the converter, which operation will resume upon the opening of said switching means; and, sensing means responsive to the movement of component parts of an engine to develop signals As a function of time representative of the proper timing to be applied to said control means to actuate said switch means and apply firing potential to the spark plugs from said output winding in timed relation to the movement of the engine, wherein said control means includes electrical storage means adapted to transfer electrical energy to said switching means to actuate same in response to a signal from said sensing means and a feedback means connected between said output transformer and said electrical storage means adapted to feed a small portion of the electrical energy developed in said output transformer to said electrical storage means to substantially completely reverse charge same on discharge of the discharge capacitor thereby to prevent more than a single effective discharge in the discharge circuit during a single discharge cycle.

Claim 8

An ignition circuit for internal combustion engines and rotating turbine engines having a spark plug in each combustion chamber comprising: a source of direct current; a DC to DC converter connected thereto including a pair of transistors, transformer means coupling said transistors through the primary winding thereof to provide a variable frequency oscillator circuit including a portion of the transformer primary winding in the feedback circuit thereof, and rectifier means connected across the secondary winding of said transformer to rectify the output signals developed in the secondary winding of the converter transformer; an output transformer having a primary winding and an output winding; a storage capacitor serially connected across the output of said converter; switching means also connected across the output of the converter in parallel with said output transformer and said capacitor; control means adapted to actuate said switch means to provide a short circuit low impedance electrical path therethrough for the discharge of an electrical charge stored in the storage capacitor through the output transformer and at the same time by means of a reflected load from the secondary winding of the converter transformer to the primary winding thereof to effectively remove the drive to the transistor oscillators and momentarily interrupt the operation of the converter, which operation will resume upon the opening of said switching means; and, sensing means responsive to the movement of component parts of an engine to develop signals As a function of time representative of the proper timing to be applied to said control means to actuate said switch means and apply firing potential to the spark plugs from said output winding in timed relation to the movement of the engine, wherein said control means includes electrical storage means adapted to transfer electrical energy to said switching means to actuate same in response to a signal from said sensing means and a feedback means connected between said output transformer and said electrical storage means adapted to feed a small portion of the electrical energy developed in said output transformer to said electrical storage means to substantially completely reverse charge same on discharge of the discharge capacitor thereby to prevent more than a single effective discharge in the discharge circuit during a single discharge cycle.

Claim 9

The circuit of claim 6 including delay means adapted to introduce a predetermined time delay before the electrical storage means of the control means can be recharged after a signal from the sensing means has been received and the electrical energy has been transferred.

Claim 10

The circuit of claim 6 wherein said switching means includes rectifier means having a cathode and a switching electrode forming triggers of opposite polarity, signal path means connecting both said cathode and said switching electrode to potentials of opposite polarity to apply a reverse gate voltage thereto in the absence of a developed signal from the sensing means.

Claim 11

The circuit of claim 8 wherein the signal path means connected to said cathode further includes a unidirectional current means and a charge storage means, which storage means serves to reverse bias the rectifier means wherever the DC potential of the charging circuit falls below the potential of the charge storage means.