Electronic fuel injection system having coarse and fine speed compensation

Claim 2

In an internal combustion engine system including control pulse generator means for producing control pulses collectively having a frequency proportional to the speed of the engine and individually having a length determined as a function of at least one engine operating parameter, and including fuel supply means connected between the control pulse generator means and the engine for applying fuel to the engine in an amount determined by the length of each of the control pulses; the combination comprising: speed voltage generator means for developing a speed voltage which varies over a time period repetitively defined as a function of the speed of the engine and which varies at a slope which is defined as a function of the speed of the engine and which is constant for any given engine speed; pulse length control means connected between the speed voltage generator means and the control pulse generator means for additionally defining the length of the control pulses as a function of the speed voltage during each of the control pulses thereby to compensate the quantity of fuel applied to the engine in response to the speed of the engine such that the time period of the speed voltage provides a coarse speed compensation and the slope of the speed voltage provides a fine speed compensation.

Claim 3

In an internal combustion engine system including control pulse generator means for producing control pulses collectively having a frequency proportional to the speed of the engine and individually having a length determined as a function of at least one engine operating parameter, and including fuel supply means connected between the control pulse generator means and the engine for applying fuel to the engine in an amount determined by the length of each of the control pulses; the combination comprising: speed voltage generator means for developing a speed voltage having an amplitude which varies over a time period defined as a function of the total time interval between the termination of successive control pulses and which varies at a rate of change which is defined as a function of the frequency of the control pulses and which is constant for any given control pulse frequency; pulse length control means connected between the speed voltage generator means and the control pulse generator means for additionally defining the length of the control pulses as a function of the amplitude of the speed voltage during each of the control pulses thereby to compensate the quantity of fuel applied to the engine for variations in the speed of the engine such that the time period over which the amplitude of the speed voltage varies provides a first order speed compensation and the rate of change in the amplitude of the speed voltage provides a second order speed compensation.

Claim 4

In an internal combustion engine system including control pulse generator means for producing control pulses collectively having a frequency proportional to the speed of the engine and individually having a length determined as a function of at least one engine operating parameter, and including fuel supply means connected between the control pulse generator means and the engine for applying fuel to the engine in an amount determined by the length of each of the control pulses; the combination comprising: speed voltage generator means for developing a speed voltage having an amplitude which varies over a time period defined as a function of the total time interval between the termination of successive control pulses and which varies at a rate of change which is defined as a function of the frequency of the control pulses and which is constant for any given control pulse frequency; pulse length control means connected between the speed voltage generator means and the control pulse generator means for additionally defining the length of the control pulses as a function of the amplitude of the speed voltage during each of the control pulses thereby to compensate the quantity of fuel applied to the engine for variations in the speed of the engine such that the time period over which the amplitude of the speed voltage varies provides a first order speed compensation and the rate of change in the amplitude of the speed voltage provides a second order speed compensation.

Claim 5

In an internal combustion engine system including control pulse generator means for producing control pulses collectively having a frequency proportional to the speed of the engine and individually having a length determined as a function of at least one engine operating parameter, and including fuel supply means connected between the control pulse generator means and the engine for applying fuel to the engine in a quantity determined by the length of each of the control pulses; the combination comprising: a capacitor for developing a speed voltage thereacross; pulse length control means connected between the capacitor and the control pulse generator means for defining the length of the control pulses in response to the amplitude of the speed voltage during each of the control pulses; discharging means connected to the capacitor for discharging the capacitor at a rapid discharge rate over a fixed discharge period to clamp the amplitude of the speed voltage at a base level at the termination of the discharge period which is initiated in response to the termination of each preceding control pulse; charging means connected to the capacitor for charging the capacitor at a constant charge rate to linearly vary the amplitude of the speed voltage from the base level toward a maximum level over a variable charge period initiated in response to the termination of each preceding discharge period and terminated in response to the termination of each succeeding control pulse thereby to provide a coarse speed compensation, the charging means including charge rate control means connected with the engine for shifting the charge rate between at least two different values in response to the speed of the engine thereby to provide a fine speed compensation.

Claim 6

In an internal combustion engine system including control pulse generator means for producing control pulses collectively having a frequency proportional to the speed of the engine and individually having a length determined as a function of at least one engine operating parameter, and including fuel supply means connected between the control pulse generator means and the engine for applying fuel to the engine in a quantity determined by the length of each of the control pulses; the combination comprising: a capacitor for developing a speed voltage thereacross; pulse length control means connected between the capacitor and the control pulse generator means for defining the length of the control pulses in response to the amplitude of the speed voltage during each of the control pulses; discharging means connected to the capacitor for discharging the capacitor at a rapid discharge rate over a fixed discharge period to clamp the amplitude of the speed voltage at a base level at the termination of the discharge period which is initiated in response to the termination of each preceding control pulse; charging means connected to the capacitor for charging the capacitor at a constant charge rate to linearly vary the amplitude of the speed voltage from the base level toward a maximum level over a variable charge period initiated in response to the termination of each preceding discharge period and terminated in response to the termination of each succeeding control pulse thereby to provide a coarse speed compensation, the charging means including charge rate control means connected with the engine for shifting the charge rate between at least two different values in response to the speed of the engine thereby to provide a fine speed compensation.

Claim 7

In an internal combustion engine system including control pulse generator means for producing control pulses collectively having a frequency proportional to the speed of the engine and individually having a length determined as a function of at least one engine operating parameter, and including fuel supply means connected between the control pulse generator means and the engine for applying fuel to the engine in a quantity determined by the length of the control pulses; the combination comprising: a capacitor for developing a speed voltage thereacross; pulse length control means connected between the capacitor and the control pulse generator means for defining the length of the control pulses as a function of the amplitude of the speed voltage during each of the control pulses; speed pulse generator means for developing speed pulses each initiated iN response to the termination of a control pulse thereby to define the termination of a charge period and the initiation of a discharge period and each terminated in response to the expiration of a predetermined time period following the termination of each control pulse thereby to define the termination of a discharge period and the initiation of a charge period; discharging means connected to the capacitor for discharging the capacitor at a rapid discharge rate over the discharge period to clamp the amplitude of the speed voltage at a base level at the termination of each discharge period; charging means connected to the capacitor for charging the capacitor at a constant charge rate over the duration of each charge period to linearly increase the amplitude of the speed voltage from the base level toward a peak level thereby to provide a first order speed compensation, the charging means including charge rate control means connected with the engine for shifting the charge rate from a first value to a second value as the speed of the engine passes through a predetermined engine speed thereby to provide a fine speed compensation.

Claim 8

In an internal combustion engine system including control pulse generator means for producing control pulses collectively having a frequency proportional to the speed of the engine and individually having a length determined as a function of at least one engine operating parameter, and including fuel supply means connected between the control pulse generator means and the engine for applying fuel to the engine in a quantity determined by the length of the control pulses; the combination comprising: a capacitor for developing a speed voltage thereacross; pulse length control means connected between the capacitor and the control pulse generator means for defining the length of the control pulses as a function of the amplitude of the speed voltage during each of the control pulses; speed pulse generator means for developing speed pulses each initiated iN response to the termination of a control pulse thereby to define the termination of a charge period and the initiation of a discharge period and each terminated in response to the expiration of a predetermined time period following the termination of each control pulse thereby to define the termination of a discharge period and the initiation of a charge period; discharging means connected to the capacitor for discharging the capacitor at a rapid discharge rate over the discharge period to clamp the amplitude of the speed voltage at a base level at the termination of each discharge period; charging means connected to the capacitor for charging the capacitor at a constant charge rate over the duration of each charge period to linearly increase the amplitude of the speed voltage from the base level toward a peak level thereby to provide a first order speed compensation, the charging means including charge rate control means connected with the engine for shifting the charge rate from a first value to a second value as the speed of the engine passes through a predetermined engine speed thereby to provide a fine speed compensation.

Claim 9

In an internal engine system exhibiting an optimum speed compensation curve representing compensation percentage versus engine speed where the compensation percentage is the desired percentage change in the quantity of fuel normally delivered to the engine at a given engine speed, the combination comprising: control pulse generator means for producing control pulses collectively having a frequency proportional to the speed of the engine and individually having a duration determined as a function of at least one engine operating parameter; fuel supply means connected between the control pulse generator means and the engine for applying fuel to the engine in an amount determined by the duration of each of the control pulses; speed voltage generator means for developing a speed voltage which varies at a constant slope over a time period defined as a function of the speed of the engine; pulse duration control means connected between the speed voltage generator means and the control pulse generator means for additionally defining the duration of the control pulses as a function of the speed voltage during each of the control pulses; and the speed voltage generator means including slope control means for varying the slope of the speed voltage as a function of the speed of the engine in such a manner that the actual speed compensation curve approximates the optimum speed compensation curve.

Claim 10

In an internal engine system exhibiting an optimum speed compensation curve representing compensation percentage versus engine speed where the compensation percentage is the desired percentage change in the quantity of fuel normally delivered to the engine at a given engine speed, the combination comprising: control pulse generator means for producing control pulses collectively having a frequency proportional to the speed of the engine and individually having a duration determined as a function of at least one engine operating parameter; fuel supply means connected between the control pulse generator means and the engine for applying fuel to the engine in an amount determined by the duration of each of the control pulses; speed voltage generator means for developing a speed voltage which varies at a constant slope over a time period defined as a function of the speed of the engine; pulse duration control means connected between the speed voltage generator means and the control pulse generator means for additionally defining the duration of the control pulses as a function of the speed voltage during each of the control pulses; and the speed voltage generator means including slope control means for varying the slope of the speed voltage as a function of the speed of the engine in such a manner that the actual speed compensation curve approximates the optimum speed compensation curve.

Claim 11

In an internal combustion engine system exhibiting an optimum speed compensation curve representing compensation percentage versus engine speed where the compensation percentage is the percentage change in the total quantity of fuel delivered to the engine at a given engine speed, the combination comprising: control pulse generator means for producing control pulses collectively having a frequency proportional to the speed of the engine and individually having a duration determined as a function of at least one engine operating parameter; fuel supply means connected between the control pulse generator means and the engine for applying fuel to the engine in an amount determined by the duration of each of the control pulses; speed voltage generator means for developing a speed voltage having an amplitude which varies at a constant rate of change over a time period defined as a function of the total time interval between the termination of successive control pulses; and pulse duration control means connected between the speed voltage generator means for additionally defining the duration of the control pulses as a function of the amplitude of the speed voltage thereby to define an actual speed compensation curve dependent upon the rate of change in the amplitude of the speed voltage; the speed voltage generator means including amplitude control means for shifting the rate of change in the amplitude of the speed voltage to different predetermined change rates as The speed of the engine reaches different predetermined engine speeds where the predetermined change rates and the predetermined engine speeds are selected so that the actual speed compensation curve is a stepped approximation to the optimum speed compensation curve.

Claim 12

In an internal combustion engine system exhibiting an optimum speed compensation curve representing compensation percentage versus engine speed where the compensation percentage is the percentage change in the total quantity of fuel delivered to the engine at a given engine speed, the combination comprising: control pulse generator means for producing control pulses collectively having a frequency proportional to the speed of the engine and individually having a duration determined as a function of at least one engine operating parameter; fuel supply means connected between the control pulse generator means and the engine for applying fuel to the engine in an amount determined by the duration of each of the control pulses; speed voltage generator means for developing a speed voltage having an amplitude which varies at a constant rate of change over a time period defined as a function of the total time interval between the termination of successive control pulses; and pulse duration control means connected between the speed voltage generator means for additionally defining the duration of the control pulses as a function of the amplitude of the speed voltage thereby to define an actual speed compensation curve dependent upon the rate of change in the amplitude of the speed voltage; the speed voltage generator means including amplitude control means for shifting the rate of change in the amplitude of the speed voltage to different predetermined change rates as The speed of the engine reaches different predetermined engine speeds where the predetermined change rates and the predetermined engine speeds are selected so that the actual speed compensation curve is a stepped approximation to the optimum speed compensation curve.

Claim 13

In an internal combustion engine system exhibiting an optimum speed compensation curve representing compensation percentage versus engine speed where the compensation percentage is the desired percentage change in the quantity of fuel normally delivered to the engine at a given engine speed, the combination comprising: control pulse generator means for producing control pulses collectively having a frequency proportional to the speed of the engine and individually having a duration determined as a function of at least one engine operating parameter; fuel supply means connected between the control pulse generator means and the engine for applying fuel to the engine in an amount determined by the duration of each of the control pulses; a capacitor for developing a speed voltage thereacross; pulse duration control means connected between the capacitor and the control pulse generator means for defining the duration of the control pulses in response to the amplitude of the speed voltage during each of the control pulses; means connected to the capacitor for discharging the capacitor at a rapid discharge rate over a fixed discharge period to clamp the amplitude of the speed voltage at a base level at the termination of the discharge period which is initiated in response to the termination of each preceding control pulse; means connected to the capacitor for charging the capacitor at a constant charge rate to linearly vary the amplitude of the speed voltage from the base level toward a maximum level over a variable charge period initiated in response to the termination of each preceding discharge period and terminated in response to the termination of each succeeding control pulse thereby to provide an actual speed compensation curve dependent upon the charge rate; and the means further connected to the control pulse generator means for shifting the charge rate to different ones of a plurality of predetermined charge rates as the frequency of the control pulses reaches different ones of a plurality of frequencies corresponding to different ones of a plurality of predetermined engine speeds where the predetermined charge rates and predetermined engine speeds are selected so that the actual speed compensation curve is a least square-error fit to the optimum speed compensation curve.

Claim 14

In an internal combustion engine system exhibiting an optimum speed compensation curve representing compensation percentage versus engine speed where the compensation percentage is the desired percentage change in the quantity of fuel normally delivered to the engine at a given engine speed, the combination comprising: control pulse generator means for producing control pulses collectively having a frequency proportional to the speed of the engine and individually having a duration determined as a function of at least one engine operating parameter; fuel supply means connected between the control pulse generator means and the engine for applying fuel to the engine in an amount determined by the duration of each of the control pulses; a capacitor for developing a speed voltage thereacross; pulse duration control means connected between the capacitor and the control pulse generator means for defining the duration of the control pulses in response to the amplitude of the speed voltage during each of the control pulses; means connected to the capacitor for discharging the capacitor at a rapid discharge rate over a fixed discharge period to clamp the amplitude of the speed voltage at a base level at the termination of the discharge period which is initiated in response to the termination of each preceding control pulse; means connected to the capacitor for charging the capacitor at a constant charge rate to linearly vary the amplitude of the speed voltage from the base level toward a maximum level over a variable charge period initiated in response to the termination of each preceding discharge period and terminated in response to the termination of each succeeding control pulse thereby to provide an actual speed compensation curve dependent upon the charge rate; and the means further connected to the control pulse generator means for shifting the charge rate to different ones of a plurality of predetermined charge rates as the frequency of the control pulses reaches different ones of a plurality of frequencies corresponding to different ones of a plurality of predetermined engine speeds where the predetermined charge rates and predetermined engine speeds are selected so that the actual speed compensation curve is a least square-error fit to the optimum speed compensation curve.

Claim 15

In an internal combustion engine system exhibiting an optimum speed compensation curve representing compensation percentage versus engine speed where the compensation percentage is the desired percentage change in the quantity of fuel normally delivered to the engine at a given engine speed, the combination comprising: control pulse generator means for producing control pulses collectively having a frequency proportional to the speed of the engine and individually having a length determined as a function of at least one engine operating parameter; fuel supply means connected between the control pulse generator means and the engine for applying fuel to the engine in a quantity determined by the length of the control pulses; a capacitor for developing a speed voltage thereacross; pulse duration control means connected between the capacitor and the control pulse generator for defining the duration of the control pulses as a function of the amplitude of the speed voltage during each of the control pulses; speed pulse generator means for developing speed pulses each initiated in response to the termination of a control pulse thereby to define the termination of a charge period and the initiation of a discharge period and each terminated in response to the expiration of a predetermined time period following the termination of each control pulse thereby to define the termination of a discharge period and the initiation of a charge period; discharging means connected to the capacitor for discharging the capacitor at a rapid discharge rate over the discharge period to clamp the amplitude of the speed voltage at a base level at the termination of each discharge period; and charging means connected to the capacitor for charging the capacitor at a constant charge rate over the duration of each charge period to linearly increase the amplitude of the speed voltage from the base level toward a maximum level thereby to provide an actual speed compensation curve which is dependent upon the charge rate; the charging means including charge rate control means connected to the speed pulse generator means for shifting charge rate to different ones of a plurality of predetermined charge rates as the frequency of the speed pulses reaches different ones of a plurality of frequencies corresponding to different ones of a plurality of predetermined engine speeds where the predetermined charge rates and the predetermined engine speeds are selected so that the actual speed compensation curve is a least square-error stepped approximation to the optimum speed compensation curve.

Claim 16

In an internal combustion engine system exhibiting an optimum speed compensation curve representing compensation percentage versus engine speed where the compensation percentage is the desired percentage change in the quantity of fuel normally delivered to the engine at a given engine speed, the combination comprising: control pulse generator means for producing control pulses collectively having a frequency proportional to the speed of the engine and individually having a length determined as a function of at least one engine operating parameter; fuel supply means connected between the control pulse generator means and the engine for applying fuel to the engine in a quantity determined by the length of the control pulses; a capacitor for developing a speed voltage thereacross; pulse duration control means connected between the capacitor and the control pulse generator for defining the duration of the control pulses as a function of the amplitude of the speed voltage during each of the control pulses; speed pulse generator means for developing speed pulses each initiated in response to the termination of a control pulse thereby to define the termination of a charge period and the initiation of a discharge period and each terminated in response to the expiration of a predetermined time period following the termination of each control pulse thereby to define the termination of a discharge period and the initiation of a charge period; discharging means connected to the capacitor for discharging the capacitor at a rapid discharge rate over the discharge period to clamp the amplitude of the speed voltage at a base level at the termination of each discharge period; and charging means connected to the capacitor for charging the capacitor at a constant charge rate over the duration of each charge period to linearly increase the amplitude of the speed voltage from the base level toward a maximum level thereby to provide an actual speed compensation curve which is dependent upon the charge rate; the charging means including charge rate control means connected to the speed pulse generator means for shifting charge rate to different ones of a plurality of predetermined charge rates as the frequency of the speed pulses reaches different ones of a plurality of frequencies corresponding to different ones of a plurality of predetermined engine speeds where the predetermined charge rates and the predetermined engine speeds are selected so that the actual speed compensation curve is a least square-error stepped approximation to the optimum speed compensation curve.