Ignition signal generating device for use in contactless ignition system

Claim 2

An ignition signal generating device for use in a contactless ignition system for an internal combustion engine comprising; a first signal generating circuit to generate a first signal at a first position corresponding to the maximum advanced ignition position of said internal combustion engine; a second signal generating circuit to generate a second signal at a second position corresponding to the minimum advanced ignition position of said internal combustion engine; a first triangular wave generating circuit to generate a first triangular wave having a given inclination rising during the period from the first signal generating position to the second signal generating position; a monostable multi-vibrator triggered by said second signal to generate a square wave signal of a given duration τ 1 ; a second triangular wave generating circuit to generate a second triangular wave having a given inclination rising during the period from a falling position of an output signal of said monostable multi-vibrator at least to said first signal generating position with the maximum value of said triangular wave being maintained until said second signal is generated; and an ignition signal generating circuit to produce an ignition signal to determine an ignition position of said internal combustion engine when the signal levels of said first and second triangular waves are equal to each other.

Claim 3

An ignition signal generating device as set forth in claim 1, and wherein said first triangular wave generating circuit comprises an integrator controlled by an output signal from a flip-flop circuit to initiate an integrating operation after said first position of said first signal generating circuit and to stop the integrating operating at said second position of said second signal generating circuit, said flip-flop circuit being set when said first signal is input and being reset when said second signal is input.

Claim 4

An ignition signal generating device as set forth in claim 1, and wherein said second triangular wave generating circuit comprises an integrator controlled by outputs from said flip-flop circuit and said monostable multi-vibrator to initiate an integrating operation after the falling position of the output from said monostable multi-vibrator and to stop the integrating operation at said first position of said first signal generating circuit, the integrated value at that time being maintained until said second position of said second signal generating circuit.

Claim 5

An ignition signal generating device as set forth in claim 1 and further comprising a duration control circuit to control the duration of the output signal from said monostable multi-vibrator in accordance with the advance characteristic.

Claim 6

An ignition signal generating device for use in a contactless ignition system for an internal combustion engine comprising: a first signal generating circuit to generate, a first signal at a first position corresponding to the maximum advanced position of said internal combustion engine; a second signal generating circuit to generate a second signal at a second position corresponding to the minimum advanced position of said internal combustion engine; a first triangular wave generating circuit to generate a first triangular wave having a given inclination rising during the period from the first signal generating position to the second signal generating position; a monostable multi-vibrator triggered by said second signal to generate a square wave signal of a given duration τ 1 ; a second triangular wave generating circuit to generate a second triangular wave having a given inclination rising during the period from a falling position of an output of said monostable multi-vibrator at least to said first signal generating position with the maximum value of said triangular wave being maintained until said second signal is generated; an ignition signal generating circuit to produce an ignition signal to determine an ignition position of said internal combustion engine when the signal levels of said first and second triangular wave are equal to each other; and, a duration control circuit to control the duration τ 1 of the output signal from said monostable multi-vibrator; said duration control circuit comprising a third signal generating circuit to generate a third signal at a third position corresponding to the position delayed more than said second position; a second monostable multi-vibrator triggered by said second signal to generate a square wave signal of a given duration τ 2 ; a flip-flop circuit controlled by said first signal from said first signal generating circuit and said third signal from said third signal generating circuit to generate an output during the period from the time when said third signal is generated to the time when said first signal is generated; a first shorting circuit to short the output from said first monostable multi-vibrator during the period during which the output from said flip-flop circuit is generated; and a second shorting circuit to short the output from said flip-flop circuit during the period during which the output from said second monostable multi-vibrator is generated.

Claim 7

An ignition signal generating device for use in a contactless ignition system for an internal combustion engine comprising: a first signal generating circuit to generate, a first signal at a first position corresponding to the maximum advanced position of said internal combustion engine; a second signal generating circuit to generate a second signal at a second position corresponding to the minimum advanced position of said internal combustion engine; a first triangular wave generating circuit to generate a first triangular wave having a given inclination rising during the period from the first signal generating position to the second signal generating position; a monostable multi-vibrator triggered by said second signal to generate a square wave signal of a given duration τ 1 ; a second triangular wave generating circuit to generate a second triangular wave having a given inclination rising during the period from a falling position of an output of said monostable multi-vibrator at least to said first signal generating position with the maximum value of said triangular wave being maintained until said second signal is generated; an ignition signal generating circuit to produce an ignition signal to determine an ignition position of said internal combustion engine when the signal levels of said first and second triangular wave are equal to each other; and, a duration control circuit to control the duration τ 1 of the output signal from said monostable multi-vibrator; said duration control circuit comprising a third signal generating circuit to generate a third signal at a third position corresponding to the position delayed more than said second position; a second monostable multi-vibrator triggered by said second signal to generate a square wave signal of a given duration τ 2 ; a flip-flop circuit controlled by said first signal from said first signal generating circuit and said third signal from said third signal generating circuit to generate an output during the period from the time when said third signal is generated to the time when said first signal is generated; a first shorting circuit to short the output from said first monostable multi-vibrator during the period during which the output from said flip-flop circuit is generated; and a second shorting circuit to short the output from said flip-flop circuit during the period during which the output from said second monostable multi-vibrator is generated.

Claim 8

An ignition signal generating device as set forth in claim 1, and wherein said ignition signal generating circuit comprises a comparator to compare said first triangular wave with said second triangular wave and a pulse generator controlled by an output from said comparator to generate a pulse signal.