Multiple pulse capacitor discharge ignition circuit

Claim 2

A multiple pulse capacitor discharge ignition circuit adapted for use with an engine ignition system having an ignition coil and ignition synchronizing means for defining ignition periods comprising: an ignition capacitor; a continuously operating, high speed charging circuit connected directly to the ignition capacitor for rapidly charging said ignition capacitor and continously supplying power for charging the ignition capacitor; a switching circuit for closing a circuit through said ignition capacitor and said ignition coil; a free running clock circuit for producing discrete, high speed switching signals independently of the charging circuit for operating said switching circuit; and a clock control circuit connected between the synchronizing means and the clock circuit so as to isolate the clock circuit from the synchronizing means, the clock control circuit being responsive to said ignition synchronizing means to enable delivery of said switching signals to said switching circuit during ignition periods to provide a plurality of current discharges from said ignition capacitor through said ignition coil, the control circuit being further responsive to termination of each ignition period by the ignition synchronizing means to disenable delivery of switching signals from the clock circuit to the switching circuit.

Claim 3

The multiple pulse capacitor discharge ignition circuit of claim 1 further including a trigger circuit, responsive to an initial signal from said ignition synchronizing means, for operating said switching circuit at the beginning of each ignition period.

Claim 4

The multiple pulse capacitor discharge ignition circuit of claim 2 further including a blanking circuit for suppressing spurious signals from said ignition synchronizing means following said initial signal in each ignition period to prevent firing of said switching circuit by any signals from said synchronizing means other than said initial signal.

Claim 5

The multiple pulse capacitor discharge ignition circuit of claim 1 in which said clock circuit includes a first semiconductor device and a timing capacitor connected to a control electrode of said first device for alternately charging to a level to fire said first device and discharging through said fired device.

Claim 6

The multiple pulse capacitor discharge ignition circuit of claim 4 in which said clock control circuit includes a second semiconductor device for providing a bias at a control electrode of said second device to cause it to conduct and means responsive to said synchronizing means, for decreasing the bias and turning off said second device during an ignition period.

Claim 7

The multiple pulse capacitor discharge ignition circuit of claim 5 in which said means for providing a bias includes a second timing capacitor for delaying for a predetermined interval the establishment of said bias on said second device.

Claim 8

The multiple pulse capacitor discharge ignition circuit of claim 1 further including a pulse amplifier circuit including a semiconductor device for amplifying said switching signals, and an additional semiconductor responsive to said amplified switching signals from said third semiconductor device for gating said switching circuit.

Claim 9

The multiple pulse capacitor discharge ignitiOn circuit of claim 2 in which said trigger circuit includes a gating semiconductor device for producing a gating input to said switching circuit and a further semiconductor device for inhibiting said gating semiconductor from providing said gating input and removing that inhibition in response to a said initial signal from said synchronizing means.

Claim 10

The multiple pulse capacitor discharge ignition circuit of claim 3 in which said trigger circuit includes a gating semiconductor device for producing a gating input to said switching circuit and a further semiconductor device for inhibiting said gating semiconductor from providing said gating input and removing that inhibition in response to said initial signal from said synchronizing means, said blanking circuit including a first delay capacitor connected to a control electrode of said further semiconductor device for communicating said initial signal to said further semiconductor device for operating said further semiconductor device to remove the inhibition from said gating semiconductor device, and subsequently charging to prevent propagation of additional signals to operate said further semiconductor device and first discharge means for discharging said first delay capacitor over a first predetermined period of time, and a second delay capacitor connected to a control electrode of said gating semiconductor device for propagating said initial signal to said gating semiconductor device for operating said gating semiconductor device in the absence of an inhibition, and subsequently charging to prevent propagation of additional signals to operate said gating semiconductor device, and second discharge means for discharging said second delay capacitor over a second predetermined period of time.

Claim 11

The multiple pulse capacitor discharge ignition circuit of claim 1 in which said charging circuit includes an astable multivibrator operating at a frequency above the frequency of said clock circuit, a power inverter responsive to said multivibrator, a high frequency step-up transformer and a rectifier responsive to said transformer.

Claim 12

The multiple pulse capacitor discharge ignition circuit of claim 10 in which said multivibrator operates at approximately 10 KHz and said clock circuit at approximately 4 KHz.

Claim 13

A multiple pulse capacitor discharge ignition circuit adapted for use with an engine ignition circuit having an ignition coil and ignition synchronizing means for defining ignition periods comprising: an ignition capacitor; a continuously operating, high speed charging circuit connected directly to the ignition capacitor for rapidly charging said ignition capacitor and continuously supplying power for charging the ignition capacitor; a switching circuit for closing a circuit through said ignition capacitor and said ignition coil; a trigger circuit having an input for direct connection to the ignition synchronizing means and responsive to an initial signal from said ignition synchronizing means, for operating said switching circuit at the beginning of each ignition period to provide an initial ignition pulse; a free running clock circuit for producing high speed switching signals for operating said switching circuit during each ignition period subsequent to operation by said trigger circuit independently of the charging circuit and trigger circuit; and a clock control circuit connected between the synchronizing means and the clock circuit so as to isolate the clock circuit from the synchronizing means, the clock control circuit being responsive to said ignition synchronizing means for enabling delivery of said switching signals to said switching circuit during ignition periods to provide a plurality of current discharges from said ignition capacitor through said ignition coil, the control circuit being further responsive to termination of each ignition period by the ignition synchronizing means to disenable delivery of switching signals from the clock circuit to the Switching circuit.

Claim 14

A multiple pulse capacitor discharge ignition circuit adapted for use with an engine ignition circuit having an ignition coil and ignition synchronizing means for defining ignition periods comprising: an ignition capacitor; a continuously operating, high speed charging circuit connected directly to the ignition capacitor for rapidly charging said ignition capacitor and continuously supplying power for charging the ignition capacitor; a switching circuit for closing a circuit through said ignition capacitor and said ignition coil; a trigger circuit having an input for direct connection to the ignition synchronizing means and responsive to an initial signal from said ignition synchronizing means, for operating said switching circuit at the beginning of each ignition period to provide an initial ignition pulse; a free running clock circuit for producing high speed switching signals for operating said switching circuit during each ignition period subsequent to operation by said trigger circuit independently of the charging circuit and trigger circuit; and a clock control circuit connected between the synchronizing means and the clock circuit so as to isolate the clock circuit from the synchronizing means, the clock control circuit being responsive to said ignition synchronizing means for enabling delivery of said switching signals to said switching circuit during ignition periods to provide a plurality of current discharges from said ignition capacitor through said ignition coil, the control circuit being further responsive to termination of each ignition period by the ignition synchronizing means to disenable delivery of switching signals from the clock circuit to the Switching circuit.

Claim 15

A multiple pulse capacitor discharge ignition circuit adapted for use with an engine ignition circuit having an ignition coil and ignition synchronizing means for defining ignition periods comprising: an ignition capacitor; a continuously operating, high speed charging circuit connected directly to the ignition capacitor for rapidly charging said ignition capacitor and continuously charging the ignition capacitor; a switching circuit for closing a circuit through said ignition capacitor and said ignition coil; a trigger circuit having an input for direct connection to the ignition synchronizing means and responsive to an initial signal from said ignition synchronizing means, for operating said switching circuit at the beginning of each ignition period to provide an initial ignition pulse; a blanking circuit for suppressing spurious signals from said ignition synchronizing means following said initial signal in each ignition period to prevent firing of said switching circuit by any signals from said synchronizing means other than said initial signal; a free running clock circuit for producing high speed switching signals for operating said switching circuit during each ignition period subsequent to operation by said trigger circuit independently of the charging circuit and trigger circuit; and a clock control circuit connected between the synchronizing means and the clock circuit so as to isolate the clock circuit from the synchronizing means, the clock control circuit being responsive to said ignition synchronizing means, for enabling delivery of said switching signals to said switching circuit during ignition periods to provide a plurality of current discharges from said ignition capacitor through said ignition coil, the control circuit being further responsive to termination of each ignition period by the ignition synchronizing means to disenable delivery of switching signals from the clock circuit to the switching circuit.

Claim 16

A multiple pulse capacitor discharge ignition circuit adapted for use with an engine ignition circuit having an ignition coil and ignition synchronizing means for defining ignition periods comprising: an ignition capacitor; a continuously operating, high speed charging circuit connected directly to the ignition capacitor for rapidly charging said ignition capacitor and continuously charging the ignition capacitor; a switching circuit for closing a circuit through said ignition capacitor and said ignition coil; a trigger circuit having an input for direct connection to the ignition synchronizing means and responsive to an initial signal from said ignition synchronizing means, for operating said switching circuit at the beginning of each ignition period to provide an initial ignition pulse; a blanking circuit for suppressing spurious signals from said ignition synchronizing means following said initial signal in each ignition period to prevent firing of said switching circuit by any signals from said synchronizing means other than said initial signal; a free running clock circuit for producing high speed switching signals for operating said switching circuit during each ignition period subsequent to operation by said trigger circuit independently of the charging circuit and trigger circuit; and a clock control circuit connected between the synchronizing means and the clock circuit so as to isolate the clock circuit from the synchronizing means, the clock control circuit being responsive to said ignition synchronizing means, for enabling delivery of said switching signals to said switching circuit during ignition periods to provide a plurality of current discharges from said ignition capacitor through said ignition coil, the control circuit being further responsive to termination of each ignition period by the ignition synchronizing means to disenable delivery of switching signals from the clock circuit to the switching circuit.

Claim 17

The multiple pulse capacitor discharge ignition circuit of claim 2 further including an OR gate connected to the clock circuit and the trigger circuit for isolating the clock circuit from the trigger circuit.