Electronic spark timing advance and emission control system

Claim 2

In a electronic ignition system for an emissions controlled internal combustion engine; electronic means for forming electrical ignition pulses in response to input signals; a first transducer for producing input signals to said electronic means at a rate related to the rotational speed of the engine and during running operation of the engine; and a second transducer equivalent to and angularly spaced from said first transducer in the direction of engine rotation for producing input signals to said electronic means at a rate related to engine speed during a starting phase of engine operation, and operator controlled means for causing said signals from said second transducer to override the signals from said first transducer and advance the timing of the engine during starting thereof for emission reduction purposes.

Claim 3

In a system as defined in claim 1 means for varying the timing of said ignition pulses relative to said input signals from the first transducer according to enginespeed and load.

Claim 4

An electronic spark timing ignition controller for an emission controlled internal combustion engine comprising in combination, a first electronic timing control channel operative during engine idle and running conditions and producing a variable spark timing advance of the firing of the engine from an initial angular firing position of the engine, said first channel including first transducer means responsive to engine rotation and having a first predetermined angular positional relationship to said initial angular firing position of the engine, a normally disabled second electronic timing control channel including second transducer means responsive to engine rotation and having a second predetermined angular positional relationship to said initial angular firing position of the engine and angularly spaced from said first transducer for producing a fixed spark timing control of the firing of the engine at said second predetermined angular position in advance of said initial angular firing position of the engine, and an operator controlled transfer means enabling said second electronic control channel and overriding said first timing control channel during the cranking phase of the engine, whereby said engine is operated during cranking at said second predetermined angular position in advance of said initial angular firing position of the engine and said engine is operated at idle after cranking at said initial angular firing position which is retarded relative to said second angular firing position and from which the spark timing may be advanced during off-idle engine running conditions.

Claim 5

An electronic spark timing ignition controller for an emission controlled internal combustion engine comprising in combination, a first electronic timing control channel operative during engine idle and running conditions and producing a variable spark timing advance of the firing of the engine from an initial angular firing position of the engine, said first channel including first transducer means responsive to engine rotation and having a first predetermined angular positional relationship to said initial angular firing position of the engine, a normally disabled second electronic timing control channel including second transducer means responsive to engine rotation and having a second predetermined angular positional relationship to said initial angular firing position of the engine and angularly spaced from said first transducer for producing a fixed spark timing control of the firing of the engine at said second predetermined angular position in advance of said initial angular firing position of the engine, and an operator controlled transfer means enabling said second electronic control channel and overriding said first timing control channel during the cranking phase of the engine, whereby said engine is operated during cranking at said second predetermined angular position in advance of said initial angular firing position of the engine and said engine is operated at idle after cranking at said initial angular firing position which is retarded relative to said second angular firing position and from which the spark timing may be advanced during off-idle engine running conditions.

Claim 6

A double-channel spark timing ignition controller in accordance with claim 3 wherein said first and second transducer means are relatively angularly spaced apart an amount corresponding to the difference between said first and second predetermined angular positions.

Claim 7

A double-channel spark timing ignition controller in accordance with claim 4 wherein said first and second transducer means each include a stationary electrical pickup separated by the aforesaid angular spacing relationship and share a common reluctor wheel driven at a rate proportional to the rotational speed of the engine and having a number of teeth thereon corresponding to the number of cylinders of the engine.

Claim 8

A double-channel spark timing ignition controller in accordance with claim 5 wherein said engine includes an ignition distributor housing said first and second transducer means and said reluctor wheel which is driven by the distributor shaft.

Claim 9

An electronic ignition system for an emissions controlled internal combustion engine in a vehicle comprising: means responsive to engine rotation for generating a first repeating signal quantity which varies during each repetition thereof as a function of the instantaneous rotational position of the engine in the operating cycle thereof; means for modulating the first signal quantity in accordance with an engine operating parameter; means for comparing the modulated first signal quantity to a substantially fixed reference signal quantity of a value to produce an ignition trigger signal when each modulated repetition of said first signal quantity bears a predetermined relationship to said reference signal quantity value; said engine operating parameter being engine load as manifested by engine vacuum and sensed by pressure responsive transducer means generating an electrical signal responsive to engine vacuum; signal scaling means connected between said pressure transducer means and said modulating means to provide a signal transfer function corresponding to the general vacuum advance characteristic of an internal combustion engine; and electronic time delay means connected between said signal scaling means and said modulating means to delay for a predetermined time interval the timing Advance otherwise called for by said signal scaling transfer function characteristic means during the transition from an engine load condition to a no-load condition.

Claim 10

An electronic ignition system for an emissions controlled internal combustion engine in a vehicle comprising: means responsive to engine rotation for generating a first repeating signal quantity which varies during each repetition thereof as a function of the instantaneous rotational position of the engine in the operating cycle thereof; means for modulating the first signal quantity in accordance with an engine operating parameter; means for comparing the modulated first signal quantity to a substantially fixed reference signal quantity of a value to produce an ignition trigger signal when each modulated repetition of said first signal quantity bears a predetermined relationship to said reference signal quantity value; said engine operating parameter being engine load as manifested by engine vacuum and sensed by pressure responsive transducer means generating an electrical signal responsive to engine vacuum; signal scaling means connected between said pressure transducer means and said modulating means to provide a signal transfer function corresponding to the general vacuum advance characteristic of an internal combustion engine; and electronic time delay means connected between said signal scaling means and said modulating means to delay for a predetermined time interval the timing Advance otherwise called for by said signal scaling transfer function characteristic means during the transition from an engine load condition to a no-load condition.

Claim 11

An electronic ignition system in accordance with claim 7 wherein said signal scaling means comprises an operational amplifier including diode-biased feedback circuits connected between the output and input thereof.

Claim 12

An electronic ignition system for an emissions controlled internal combustion engine comprising: a first source of ignition trigger signals including first means responsive to engine rotation for generating a first repeating signal quantity which varies during each repetition thereof as a function of the instantaneous rotational position of the engine in the operating cycle thereof, said means comprising transducer means for producing a d-c signal related to engine speed, integrator means connected to receive said d-c signal and means for repeatedly resetting said integrator means at predetermined engine rotation intervals; means for varying the occurrence of said ignition trigger signals from said first source relative to a predetermined angular position of the engine including means for modulating said first signal quantity in accordance with engine operating parameters, including speed and load; means for comparing the modulated first signal quantity to a substantially fixed reference signal quantity of a value to produce an ignition trigger signal when each modulated repetition of said signal quantity bears a predetermined relationship to said reference signal quantity value, a second source of ignition trigger signals separate and independent from said first mentioned means and said comparing means to produce an ignition trigger signal occurring at a fixed angular position of the engine, and operator controlled means for operating said second source during a starting phase of engine operation.

Claim 13

An electronic ignition system for an emissions controlled internal combustion engine comprising: a first source of ignition trigger signals including first means responsive to engine rotation for generating a first repeating signal quantity which varies during each repetition thereof as a function of the instantaneous rotational position of the engine in the operating cycle thereof, said means comprising transducer means for producing a d-c signal related to engine speed, integrator means connected to receive said d-c signal and means for repeatedly resetting said integrator means at predetermined engine rotation intervals; means for varying the occurrence of said ignition trigger signals from said first source relative to a predetermined angular position of the engine including means for modulating said first signal quantity in accordance with engine operating parameters, including speed and load; means for comparing the modulated first signal quantity to a substantially fixed reference signal quantity of a value to produce an ignition trigger signal when each modulated repetition of said signal quantity bears a predetermined relationship to said reference signal quantity value, a second source of ignition trigger signals separate and independent from said first mentioned means and said comparing means to produce an ignition trigger signal occurring at a fixed angular position of the engine, and operator controlled means for operating said second source during a starting phase of engine operation.

Claim 14

An electronic ignition system in accordance with claim 9 wherein said second source of ignition trigger signals includes a second transducer angularly spaced from the first transducer to produce ignition trigger pulses having a timing occurrence in advance of said predetermined initial angular firing position of the engine.

Claim 15

An electronic ignition system for an internal combustion engine comprising: means responsive to engine rotation for generating a first repeating signal quantity which varies during each repetition thereof as a function of the instantaneous rotational angular position of the engine in the operating cycle thereof including, means for producing a dc signal related to engine speed, integrator means connected to receive said dc signal and to integrate the same, and means for repeatedly resetting said integrator means at predetermined engine rotation intervals to produce said first signal quantity; means for modulating the first signal quantity in accordance with an engine operating parameter; and means for comparing the modulated first signal quantity to a substantially fixed reference signal quantity of a preselected value independent of engine speed to produce an ignition trigger signal when each modulated repetition of said first signal quantity bears a predetermined relationship to said reference signal quantity value.

Claim 16

An electronic ignition system for an internal combustion engine comprising: means responsive to engine rotation for generating a first repeating signal quantity which varies during each repetition thereof as a function of the instantaneous rotational angular position of the engine in the operating cycle thereof including, means for producing a dc signal related to engine speed, integrator means connected to receive said dc signal and to integrate the same, and means for repeatedly resetting said integrator means at predetermined engine rotation intervals to produce said first signal quantity; means for modulating the first signal quantity in accordance with an engine operating parameter; and means for comparing the modulated first signal quantity to a substantially fixed reference signal quantity of a preselected value independent of engine speed to produce an ignition trigger signal when each modulated repetition of said first signal quantity bears a predetermined relationship to said reference signal quantity value.

Claim 17

An electronic ignition system as set forth in claim 11 wherein said modulating means comprises a current-summing junction connected to receive said dc speed signal and said first signal quantity.

Claim 18

An electronic ignition system as set forth in claim 12 including at least one additional signal quantity generator for producing a second signal quantity related to engine operation; said additional generator having an output connected to said junction to further modulate the first signal quantity thereby to vary ignition timing.

Claim 19

An ignition system as defined in claim 13 wherein said second signal quantity is related to engine vacuum.

Claim 20

An ignition system as defined in Claim 12 further including an operational amplifier connected between the means for producing the dc speed signal and the summing junction to provide a voltage-speed transfer function having at least one break point.

Claim 21

An electronic ignition system for an emission-controlled internal combustion engine comprising: means responsive to engine rotation for generating a first signal quantity whose amplitude varies with engine speed and a second signal quantity whose amplitude varies independently of engine speed as a function of the instantaneous angular rotational position of the crankshaft of the engine and including signal pulse generating means having a predetermined angular positional setting relative to the engine crankshaft and driven thereby for producing a train of pulses having a repetition rate related to engine speed, pulse shaping means connected to said pulse generating means and integrator means coupled to said signal pulse generating means and electrically reset by a pulse therefrom at said predetermined angular positional setting of said signal pulse generating means relative to the engine crankshaft; means for comparing said engine angular position signal quantity with a reference signal quantity of a predetermined fixed value independent of engine speed to produce an ignition trigger signal when said engine angular position signal quantity attains a predetermined relationship to said reference signal quantity, said reference signal quantity corresponding to the value of said engine angular position signal quantity at a predetermined initial angular position of the engine from which it is desired to advance the firing of the engine after starting and during engine running conditions; means for generating a third signal quantity related to an engine operating parameter and for applying said third signal quantity to said comparing means directly with said first signal quantity, said second signal quantity and said reference signal quantity for modifying the occurrence of the engine ignition triggger signal produced at said predetermined initial angular firing position in accordance with said first and third signal quantities, and electronic time delay means connected between said third signal generating means and said comparing means for delaying the effect of said third signal quantity on said ignition trigger signal in response to a change in the engine operating parameter.

Claim 22

An electronic ignition system for an emission-controlled internal combustion engine comprising: means responsive to engine rotation for generating a first signal quantity whose amplitude varies with engine speed and a second signal quantity whose amplitude varies independently of engine speed as a function of the instantaneous angular rotational position of the crankshaft of the engine and including signal pulse generating means having a predetermined angular positional setting relative to the engine crankshaft and driven thereby for producing a train of pulses having a repetition rate related to engine speed, pulse shaping means connected to said pulse generating means and integrator means coupled to said signal pulse generating means and electrically reset by a pulse therefrom at said predetermined angular positional setting of said signal pulse generating means relative to the engine crankshaft; means for comparing said engine angular position signal quantity with a reference signal quantity of a predetermined fixed value independent of engine speed to produce an ignition trigger signal when said engine angular position signal quantity attains a predetermined relationship to said reference signal quantity, said reference signal quantity corresponding to the value of said engine angular position signal quantity at a predetermined initial angular position of the engine from which it is desired to advance the firing of the engine after starting and during engine running conditions; means for generating a third signal quantity related to an engine operating parameter and for applying said third signal quantity to said comparing means directly with said first signal quantity, said second signal quantity and said reference signal quantity for modifying the occurrence of the engine ignition triggger signal produced at said predetermined initial angular firing position in accordance with said first and third signal quantities, and electronic time delay means connected between said third signal generating means and said comparing means for delaying the effect of said third signal quantity on said ignition trigger signal in response to a change in the engine operating parameter.

Claim 23

An electronic ignition system in accordance with claim 16 wherein said pulse shaping means includes a Schmitt trigger circuit.

Claim 24

An electronic ignition system as set forth in claim 11 wherein said generating means further includes a first transducer for producing electrical signal pulses at a rate related to engine speed.

Claim 25

An electronic ignition system as set forth in claim 18 wherein said transducer comprises a low reluctance element which rotates at a rate proportional to engine speed, and an electromagnetic pickup disposed adjacent said element and magnetically linked therewith for producing said pulses.

Claim 26

An electronic ignition system in accordance with claim 18 wherein said generating means further includes signal shaping means and signal averaging means connected between said speed transducer means and said integrating means.

Claim 27

An electronic ignition system in accordance with claim 20 wherein said integrator means is reset from said signal shaping means every 2 omega /c degrees of engine rotation where omega 2 pi radians and C is the number of engine cylinders.

Claim 28

An electronic ignition system in accordance with claim 11 wherein said signal shaping means includes a Schmitt trigger and a univibrator circuit and wherein said integrator means is reset from said univibrator.

Claim 29

In an electronic spark timing advance controller for an emission-controlled internal combustion engine, the combination of means responsive to engine rotation for generating a first repeating signal quAntity which varies during each repetition thereof as a function of the instantaneous angular rotational position of the engine from a first value at a first preselected angular position of the engine to a second value at a second preselected angular position of the engine and for resetting said first signal quantity at said second preselected angular position of the engine, means for comparing said first engine angular position signal quantity against a fixed reference signal quantity of a predetermined value independent of engine speed to produce an ignition trigger signal when said first engine angular position signal quantity attains a predetermined relationship to said reference signal quantity, said fixed reference signal quantity corresponding to the value of said first engine angular position signal quantity at a predetermined initial angular position of the engine at which it is desired to produce ignition trigger signals to fire the engine at no-load, engine idling conditions, means for generating a second signal quantity and a third signal quantity each respectively related to engine load as manifested by engine vacuum and to engine speed, and for applying said second and third signal quantities to said comparing means with said first signal quantity and said reference signal quantity for modifying the occurrence of the engine ignition trigger signals from said predetermined initial angular firing position of the engine in accordance with said second and third signal quantities, and electronic time delay means connected between said second signal generating means and said comparing means for time delaying the effect of said second signal quantity on said ignition trigger signal in response to a change in engine load.

Claim 30

In an electronic spark timing advance controller for an emission-controlled internal combustion engine, the combination of means responsive to engine rotation for generating a first repeating signal quAntity which varies during each repetition thereof as a function of the instantaneous angular rotational position of the engine from a first value at a first preselected angular position of the engine to a second value at a second preselected angular position of the engine and for resetting said first signal quantity at said second preselected angular position of the engine, means for comparing said first engine angular position signal quantity against a fixed reference signal quantity of a predetermined value independent of engine speed to produce an ignition trigger signal when said first engine angular position signal quantity attains a predetermined relationship to said reference signal quantity, said fixed reference signal quantity corresponding to the value of said first engine angular position signal quantity at a predetermined initial angular position of the engine at which it is desired to produce ignition trigger signals to fire the engine at no-load, engine idling conditions, means for generating a second signal quantity and a third signal quantity each respectively related to engine load as manifested by engine vacuum and to engine speed, and for applying said second and third signal quantities to said comparing means with said first signal quantity and said reference signal quantity for modifying the occurrence of the engine ignition trigger signals from said predetermined initial angular firing position of the engine in accordance with said second and third signal quantities, and electronic time delay means connected between said second signal generating means and said comparing means for time delaying the effect of said second signal quantity on said ignition trigger signal in response to a change in engine load.

Claim 31

An electronic ignition system in accordance with claim 23 further including ambient temperature sensing means operative above a predetermined ambient temperature and connected to said delay advance means to disable operation thereof at temperatures below a predetermined ambient temperature.

Claim 32

An electronic ignition control system for an emissions controlled internal combustion engine, comprising in combination a first source of ignition trigger signals to produce ignition signals of variable timing occurrence in the operating cycle of the engine in accordance with selected engine operating parameters including first means for generating a first repeating signal quantity which varies during each repetition thereof as a function of the instantaneous angular rotational position of the engine from a first value at a first preselected angular position of the engine to a secondary value at a second preselected angular position thereof, said first means comprising first transducer means responsive to engine rotation for producing electrical signal pulses at a rate related to engine speed, means for producing a dc signal related to engine speed, integrator means connected to receive said dc signal, and means for repeatedly resetting said integrator means from said first transducer means at predetermined engine rotation intervals corresponding to said second preselected angular position of the engine. means for comparing the first signal quantity to a substantially fixed reference signal quantity of a value to produce an ignition trigger signal when said first engine angular position signal quantity attains a predetermined relationship to said reference signal quantity value, said reference signal quantity corresponding to the value of said first angular position signal quantity at a predetermined initial angular position of the engine at predetermined engine rotation intervals corresponding to said second preselected angular position of the engine, means for comparing the first signal quantity to a substantially fixed reference signal quantity of a value to produce an ignition trigger signal when said first engine angular position signal quantity attains a predetermined relationship to said reference signal qUantity value, said reference signal quantity corresponding to the value of said first angular position signal quantity at a predetermined initial angular position of the engine at which it is desired to produce said ignition trigger signals to fire the engine at no-load engine idling conditions, and means for varying the occurrence of said ignition trigger signals from said comparing means in accordance with engine speed and load operating parameters including means for generating a second signal quantity related to engine load as manifested by engine vacuum and for applying said second signal quantity and said engine speed related dc signal to said comparing means with said first signal quantity and said reference signal quantity; a second source of ignition trigger signals including second transducer means angularly spaced from said first transducer means to produce an ignition trigger signal occurring at a fixed angular position of the engine in advance of the said predetermined initial engine idling, no-load firing angular position of the engine; and operator controlled means for operating said second source of ignition trigger signals only during a starting phase of engine operation.

Claim 33

An electronic ignition control system for an emissions controlled internal combustion engine, comprising in combination a first source of ignition trigger signals to produce ignition signals of variable timing occurrence in the operating cycle of the engine in accordance with selected engine operating parameters including first means for generating a first repeating signal quantity which varies during each repetition thereof as a function of the instantaneous angular rotational position of the engine from a first value at a first preselected angular position of the engine to a secondary value at a second preselected angular position thereof, said first means comprising first transducer means responsive to engine rotation for producing electrical signal pulses at a rate related to engine speed, means for producing a dc signal related to engine speed, integrator means connected to receive said dc signal, and means for repeatedly resetting said integrator means from said first transducer means at predetermined engine rotation intervals corresponding to said second preselected angular position of the engine. means for comparing the first signal quantity to a substantially fixed reference signal quantity of a value to produce an ignition trigger signal when said first engine angular position signal quantity attains a predetermined relationship to said reference signal quantity value, said reference signal quantity corresponding to the value of said first angular position signal quantity at a predetermined initial angular position of the engine at predetermined engine rotation intervals corresponding to said second preselected angular position of the engine, means for comparing the first signal quantity to a substantially fixed reference signal quantity of a value to produce an ignition trigger signal when said first engine angular position signal quantity attains a predetermined relationship to said reference signal qUantity value, said reference signal quantity corresponding to the value of said first angular position signal quantity at a predetermined initial angular position of the engine at which it is desired to produce said ignition trigger signals to fire the engine at no-load engine idling conditions, and means for varying the occurrence of said ignition trigger signals from said comparing means in accordance with engine speed and load operating parameters including means for generating a second signal quantity related to engine load as manifested by engine vacuum and for applying said second signal quantity and said engine speed related dc signal to said comparing means with said first signal quantity and said reference signal quantity; a second source of ignition trigger signals including second transducer means angularly spaced from said first transducer means to produce an ignition trigger signal occurring at a fixed angular position of the engine in advance of the said predetermined initial engine idling, no-load firing angular position of the engine; and operator controlled means for operating said second source of ignition trigger signals only during a starting phase of engine operation.