Electronic fuel injection system

Claim 2

In an internal combustion engine exhibiting periodic engine cycles having a frequency proportional to the speed of the engine and including at least first and second operating stages of approximately equal duration per engine cycle proportional to the duration of the engine cycle, the combination comprising: means for developing injection pulses each initiated in response to the onset of the first and second operating stages and each having a duration determined as a function of at least one engine operating parameter; means for developing a speed signal having an amplitude which increases over the duration of a first portion of each engine cycle such that the amplitude of the speed signal is inversely related to the speed of the engine; means for developing a reference signal having an amplitude which is substantially constant at a reference level corresponding to an engine speed at which the duration of the injection pulses is approximately equal to the duration of the first and second operating stages; means including a differential switch operable to a first state when the amplitude of the reference signal exceeds the amplitude of the speed signal and operable to a second state when the amplitude of the speed signal exceeds the amplitude of the reference signal; means for developing timing pulses each initiated at the expiration of a second portion of each engine cycle which terminates within the first portion; means including a bistable switch operable to a first state from a second state when the differential switch is in the first state at the initiation of a timing pulse; and means including a first fuel injector for applying fuel to the engine in an amount determined by the duration of each of the injection pulses initiated in response to the onset of the first operating stage and including a second fuel injector for applying fuel to the engine in an amount determined by the duration of each of the injection pulses initiated in response to the onset of the second operating stage when the bistable switch is in the second state and for applying fuel to the engine in an amount determined by the duration of each of the injection pulses initiated in response to the onset of the first operating stage when the bistable switch is in the first state; whereby the maximum duration of the injection pulses is extended beyond the duration of either one of the first and second operating stages.

Claim 3

In an internal combustion engine exhibiting periodic engine cycles having a frequency proportional to the speed of the engine and including at least first and second operating stages of approximately equal duration per engine cycle proportional to the duration of the engine cycle, the combination comprising: means for developing injection pulses each initiated in response to the first and second operating stages and each having a duration determined as a function of at leAst one engine operating parameter; means including a speed signal generator for developing a speed signal having an amplitude which increases from a base level toward a maximum level over the duration of a first portion of each engine cycle so that the amplitude of the speed signal is inversely related to the speed of the engine; means including a reference signal generator for developing a refernce signal having an amplitude which is substantially constant; means including a differential switch operable to a first state when the amplitude of the reference signal exceeds the amplitude of the speed signal and operable to a second state when the amplitude of the speed signal exceeds the amplitude of the reference signal; means including a timing pulse generator for developing timing pulses each initiated at the expiration of a second portion of each engine cycle which is terminated within the first fixed portion; means including a bistable switch operable to a first state from a second state when the differential switch is in the first state at the initiation of a timing pulse; the reference signal generator including means for defining the amplitude of the reference signal at a lower reference level located between the base level and the maximum level at a point corresponding to an engine speed at which the duration of the first and second operating stages is approximately equal to the duration of the injection pulses and for defining the amplitude of the reference signal at an upper reference level located between the base level and the maximum level at a point corresponding to a second engine speed sufficiently below the first engine speed to prevent oscillation of the bistable switch; and means including a first fuel injector for applying fuel to the engine in an amount directly related to each of the injection pulses initiated in response to the onset of the first operating stage and including a second fuel injector for applying fuel to the engine in an amount determined by the duration of each of the injection pulses initiated in response to the onset of the second operating stage when the bistable switch is in the second state and for applying fuel to the engine in an amount determined by the duration of each of the injection pulses initiated in response to the onset of the first operating stage when the bistable switch is in the first state; whereby the duration of the injection pulses is extended beyond the duration of either one of the first and second operating stages.

Claim 4

In an internal combustion engine exhibiting periodic engine cycles having a frequency proportional to the speed of the engine and including at least first and second operating stages of approximately equal duration per engine cycle proportional to the duration of the engine cycle, the combination comprising: means for developing injection pulses each initiated in response to the first and second operating stages and each having a duration determined as a function of at leAst one engine operating parameter; means including a speed signal generator for developing a speed signal having an amplitude which increases from a base level toward a maximum level over the duration of a first portion of each engine cycle so that the amplitude of the speed signal is inversely related to the speed of the engine; means including a reference signal generator for developing a refernce signal having an amplitude which is substantially constant; means including a differential switch operable to a first state when the amplitude of the reference signal exceeds the amplitude of the speed signal and operable to a second state when the amplitude of the speed signal exceeds the amplitude of the reference signal; means including a timing pulse generator for developing timing pulses each initiated at the expiration of a second portion of each engine cycle which is terminated within the first fixed portion; means including a bistable switch operable to a first state from a second state when the differential switch is in the first state at the initiation of a timing pulse; the reference signal generator including means for defining the amplitude of the reference signal at a lower reference level located between the base level and the maximum level at a point corresponding to an engine speed at which the duration of the first and second operating stages is approximately equal to the duration of the injection pulses and for defining the amplitude of the reference signal at an upper reference level located between the base level and the maximum level at a point corresponding to a second engine speed sufficiently below the first engine speed to prevent oscillation of the bistable switch; and means including a first fuel injector for applying fuel to the engine in an amount directly related to each of the injection pulses initiated in response to the onset of the first operating stage and including a second fuel injector for applying fuel to the engine in an amount determined by the duration of each of the injection pulses initiated in response to the onset of the second operating stage when the bistable switch is in the second state and for applying fuel to the engine in an amount determined by the duration of each of the injection pulses initiated in response to the onset of the first operating stage when the bistable switch is in the first state; whereby the duration of the injection pulses is extended beyond the duration of either one of the first and second operating stages.

Claim 5

In an internal combustion engine exhibiting periodic engine cycles having a frequency proportional to the speed of the engine and having at least first and second operating stages of approximately equal duration per engine cycle proportional to the duration of the engine cycle, the combination comprising: means including a first control pulse generator for developing first control pulses each initiated in response to the onset of the first and second operating stages and each terminated at the expiration of a first predetermined duration; means including a second control pulse generator for developing second control pulses each initiated after the initiation of a corresponding first control pulse and each terminated after the termination of the corresponding first control pulse at the expiration of a second predetermined duration; and means for developing injection pulses each initiated in response to the initiation of a first control pulse and each terminated in response to the termination of the corresponding second control pulse; means including a speed signal generator for developing a speed signal having an amplitude which increases over the duration of a first portion of each engine cycle such that the amplitude of the speed signal is inversely related to the speed of the engine; means for developing a reference signal having an amplitude which is substantially constant at a reference level corresponding to an engine speed at which the duration of the injection pulses is approximately equAl to the duration of the first and second operating stages; means including a differential switch operable to a first state when the amplitude of the reference signal exceeds the amplitude of the speed signal and operable to a second state when the amplitude of the speed signal exceeds the amplitude of the reference signal; and means including a timing pulse generator for developing timing pulses each initiated in response to the initiation of a first control pulse such that each of the timing pulses is initiated at the expiration of a second portion of each engine cycle which terminates within the first portion; means including a bistable switch operable to a first state from a second state when the differential switch is in the first state at the initiation of a timing pulse; and means including a first fuel injector for applying fuel to the engine in an amount determined by the duration of each of the injection pulses initiated in response to the onset of the first operating stage and including a second fuel injector for applying fuel to the engine in an amount determined by the duration of each of the injection pulses initiated in response to the onset of the second operating stage when the bistable switch is in the second state and for applying fuel to the engine in an amount determined by the duration of each of the injection pulses initiated in response to the onset of the first operating stage when the bistable switch is in the first state; whereby the maximum duration of the injection pulses is extended beyond the duration of either one of the first and second operating stages.

Claim 6

In an internal combustion engine exhibiting periodic engine cycles having a frequency proportional to the speed of the engine and having at least first and second operating stages of approximately equal duration per engine cycle proportional to the duration of the engine cycle, the combination comprising: means including a first control pulse generator for developing first control pulses each initiated in response to the onset of the first and second operating stages and each terminated at the expiration of a first predetermined duration; means including a second control pulse generator for developing second control pulses each initiated after the initiation of a corresponding first control pulse and each terminated after the termination of the corresponding first control pulse at the expiration of a second predetermined duration; and means for developing injection pulses each initiated in response to the initiation of a first control pulse and each terminated in response to the termination of the corresponding second control pulse; means including a speed signal generator for developing a speed signal having an amplitude which increases over the duration of a first portion of each engine cycle such that the amplitude of the speed signal is inversely related to the speed of the engine; means for developing a reference signal having an amplitude which is substantially constant at a reference level corresponding to an engine speed at which the duration of the injection pulses is approximately equAl to the duration of the first and second operating stages; means including a differential switch operable to a first state when the amplitude of the reference signal exceeds the amplitude of the speed signal and operable to a second state when the amplitude of the speed signal exceeds the amplitude of the reference signal; and means including a timing pulse generator for developing timing pulses each initiated in response to the initiation of a first control pulse such that each of the timing pulses is initiated at the expiration of a second portion of each engine cycle which terminates within the first portion; means including a bistable switch operable to a first state from a second state when the differential switch is in the first state at the initiation of a timing pulse; and means including a first fuel injector for applying fuel to the engine in an amount determined by the duration of each of the injection pulses initiated in response to the onset of the first operating stage and including a second fuel injector for applying fuel to the engine in an amount determined by the duration of each of the injection pulses initiated in response to the onset of the second operating stage when the bistable switch is in the second state and for applying fuel to the engine in an amount determined by the duration of each of the injection pulses initiated in response to the onset of the first operating stage when the bistable switch is in the first state; whereby the maximum duration of the injection pulses is extended beyond the duration of either one of the first and second operating stages.