FUEL SUPPLY SYSTEM FOR AN INTERNAL COMBUSTION ENGINE PROVIDING VOLTAGE COMPENSATED CRANKING ENRICHMENT

• US 3,683,871 A
• Filed: 07/17/1970
• Issued: 08/15/1972
• Est. Priority Date: 07/17/1970
• Status: Expired due to Term

• Current Assignee: Charles C. Gambill, Paul N. Barr
• Original Assignee: Charles C. Gambill, Paul N. Barr
• Inventors: Barr, Paul N., Gambill, Charles C.
• Primary Examiner(s): Goodridge, Laurence M.
• Assistant Examiner(s): Cox, Ronald B.
• Application Number:
  US05/055,831
• Time in Patent Office: 760 Days
• Field of Search: 123/32EL,179G,179L
• US Class Current: 123/491
• CPC Class Codes: F02D 41/065 at hot start or restart F02D41/067 takes precedence

Abstract

In an electronic fuel injection system, fuel is applied to an internal combustion engine for the duration of individual control pulses developed in synchronization with the engine rotation. During cranking of the engine, additional control pulses are supplied at a frequency which is inversely related to the temperature of the engine and which is also inversely related to the supply voltage of a power source. In a preferred embodiment, the frequency of the additional control pulses is doubled when the supply voltage falls below a minimum acceptable level.

Claims

1. In an internal combustion engine system, the combination comprising:

a power source for providing a supply voltage;

starter means connected with the engine for cranking the engine at a speed determined as a direct function of the supply voltage when energized by the power source;

means connected between the starter means and the power source for selectively energizing the starter means with the supply voltage to crank the engine;

cranking generator means connected with the starter means for producing cranking pulses when the starter means is energized, the cranking generator means including voltage detector means connected with the power source for defining the frequency of the cranking pulses as an inverse function of the supply voltage when the energy capacity of the power source is below normal; and

means including fuel injection means for normally applying fuel to the engine in an amount directly related to the engine speed and for additionally applying a predetermined amount of fuel to the engine in response to each cranking pulse so that the quantity of fuel delivered to the engine during cranking is compensated for variAtions in the supply voltage of the power source.

2. In an internal combustion engine system, the combination comprising:

a power source for providing a supply voltage;

means including at least one voltage responsive fuel injector connected with the engine for applying fuel to the engine at a substantially constant rate when energized by the supply voltage;

starter means connected with the engine for cranking the engine at an output speed determined as a direct function of the supply voltage when energized by the supply voltage;

means connected between the starter means and the power source for selectively energizing the starter means with the supply voltage to crank the engine;

timing generator means connected with the engine for producing timing pulses having a frequency determined as a direct function of the output speed of the engine;

cranking generator means connected with the starter means for producing cranking pulses having a given frequency when the starter means is energized, the cranking generator means including voltage detector means connected to the power source for increasing the frequency of the cranking pulses when the supply voltage falls below a minimum acceptable level which indicates that the energy capacity of the power source is below normal; and

means connected with the timing generator means and the cranking generator means and connected between the fuel injector and the power source for energizing the fuel injector with the supply voltage for a predetermined time period in response to each of the timing pulses and each of the cranking pulses so that the amount of fuel applied to the engine during cranking is compensated for variations in the supply voltage.

3. In an internal combustion engine system, the combination comprising:

a power source for providing a supply voltage;

means including at least one fuel injector connected with the engine for applying fuel to the engine at a substantially constant rate when energized by the supply voltage from the power source;

starter means connected with the engine for cranking the engine at an output speed directly related to the supply voltage when energized from the power source;

means connected between the starter means and the power source for selectively energizing the starter means with the supply voltage to crank the engine;

timing generator means connected with the engine for producing timing pulses having a frequency directly related to the output speed of the engine;

cranking generator means connected with the starter means for producing cranking pulses when the starter means is energized, the cranking generator means including voltage detector means connected with the power source for defining the frequency of the cranking pulses in inverse relation to the supply voltage when the energy capacity of the power source is below normal, the cranking generator means further including heat sensor means connected with the engine for defining the frequency of the cranking pulses in inverse relation to the temperature of the engine; and

means connected with the timing generator means and the cranking generator means and connected between the fuel injector and the power source for energizing the fuel injector with the supply voltage for a predetermined time period in response to each of the timing pulses and each of the cranking pulses so that the amount of fuel applied to the engine during cranking is compensated for variations in the supply voltage of the power source and for variations in the temperature of the engine.

4. In an internal combustion engine, the combination comprising:

a power source for providing electrical energy at a supply voltage;

means including at least one voltage responsive fuel injector connected with the engine for applying fuel to the engine at a substantially constant rate when energized by the supply voltage;

starter means connected with the engine for cranking the engine at an output speed directly related to the supply voltage when energized from the power source;

meanS including a starter switch connected between the starter means and the power source for selectively energizing the starter means with the supply voltage to crank the engine;

timing generator means connected with the engine for producing timing pulses having a frequency directly related to the output speed of the engine;

cranking oscillator means connected with the starter means for producing cranking pulses when the starter means is energized, the cranking oscillator means including oscillator control means for producing a control voltage having an excursion rate which determines the frequency of the cranking pulses, the oscillator control means including voltage detector means connected with the power source for regulating the excursion rate of the control voltage such that the frequency of the cranking pulses is inversely related to the supply voltage when the energy capacity of the power source is below normal; and

means connected with the timing generator means and the cranking oscillator means and connected between the fuel injector and the power source for energizing the fuel injector with the supply voltage for a predetermined time period in response to each of the timing pulses and each of the cranking pulses so that the amount of fuel applied to the engine during cranking is compensated for variations in the supply voltage.

5. In an internal combustion engine, the combination comprising:

a power source for providing electrical energy at a supply voltage;

means including at least one voltage responsive fuel injector connected with the engine for applying fuel to the engine at a substantially constant rate when energized by the supply voltage;

starter means connected with the engine for cranking the engine at an output speed directly related to the supply voltage when energized from the power source;

means including a starter switch connected between the starter means and the power source for selectively energizing the starter means with the supply voltage to crank the engine;

timing generator means connected with the engine for producing timing pulses having a frequency directly related to the output speed of the engine;

cranking oscillator means connected with the starter means for producing cranking pulses when the starter means is in the actuated condition, the cranking oscillator means including oscillator control means for producing a control voltage which alternately varies at a first excursion rate to a first control level and at a second excursion rate to a second control level, the oscillator control means including voltage detector means connected with the power source for regulating at least one of the first and second excursion rates as an inverse function of the supply voltage when the energy capacity of the power source is below normal, the control voltage defining the frequency of the cranking pulses as a direct function of the first and second excursion rates so that the frequency of the cranking pulses is inversely related to the supply voltage; and

means connected with the timing generator means and the cranking oscillator means and connected between the fuel injector and the power source for energizing the fuel injector with the supply voltage for a predetermined time period in response to each of the timing pulses and each of the cranking pulses so that the amount of fuel applied to the engine during cranking is compensated for variations in the supply voltage.

6. In an internal combustion engine, the combination comprising:

a power source for providing electrical energy at a supply voltage;

means including at least one voltage responsive fuel injector connected with the engine for applying fuel to the engine at a substantially constant rate when energized by the supply voltage;

starter means connected with the engine for cranking the engine at an output speed directly related to the supply voltage when energized from the power source;

means including a starter switch connected between the starter means and the power source for selectively energiZing the starter means with the supply voltage to crank the engine;

timing generator means connected with the engine for producing timing pulses having a frequency directly related to the output speed of the engine;

cranking oscillator means connected with the starter means for producing cranking pulses when the starter means is actuated, the cranking oscillator means including oscillator control means for producing a control voltage which alternately increases to an upper control level at a positive excursion rate and decreases to a lower control level at a negative excursion rate, the oscillator control means including voltage detector means connected with the power source for increasing at least one of the positive and negative excursion rates when the supply voltage decreases below a minimum acceptable level which indicates that the energy capacity of the power source is below normal, the control voltage defining the frequency of the cranking pulses in direct relation to the positive and negative excursion rates so as to increase the frequency of the cranking pulses when the supply voltage decreases below the minimum acceptable level; and

means connected with the timing generator means and the cranking oscillator means and connected between the fuel injector and the power source for energizing the fuel injector with the supply voltage for a predetermined time period in response to each of the timing pulses and each of the cranking pulses so that the amount of fuel applied to the engine during cranking is compensated for variations in the supply voltage.

7. In an internal combustion engine system, the combination comprising:

a power source for providing a supply voltage;

fuel injection means connected with the engine for applying fuel to the engine at a substantially constant rate when energized from the power source;

starter means connected with the engine for cranking the engine at an output speed directly related to the supply voltage when energized from the power source;

means including a starter switch connected between the starter means and the power source for selectively energizing the starter means with the supply voltage to crank the engine;

timing pulse generating means connected with the engine for producing timing pulses having a frequency directly related to the output speed of the engine;

cranking pulse generating means connected with the starter means for producing cranking pulses when the starter means is in the actuated condition, the cranking pulse generating means including control voltage generating means for producing a control voltage which alternately increases to an upper control level at a positive excursion rate and decreases to a lower control level at a negative excursion rate, the control voltage generating means including voltage detector means connected with the power source for increasing at least one of the positive and negative excursion rates when the supply voltage decreases below a minimum acceptable level which indicates that the energy capacity of the power source is below normal, the control voltage defining the frequency of the cranking pulses in direct relation to the positive and negative excursion rates to as to increase the frequency of the cranking pulses when the supply voltage decreases below the minimum acceptable level;

control pulse generating means connected with the timing pulse generating means and with the cranking pulse generating means for producing control pulses in response to the occurrence of the timing pulses and the cranking pulses, the control pulse generating means including transducer means connected with the engine for determining the duration of the control pulses as a function of at least one engine operating parameter; and

means connected with the control pulse generating means and connected between the fuel injection means and the power source for energizing the fuel injection means from the power source for the duration of each of the control pulses so that the amount of fuel applied to the engine during cranking and is compensated for variations in the supply voltage.

8. In an internal combustion engine, the combination comprising:

a power source for providing electrical energy at a supply voltage;

means including at least one voltage responsive fuel injector connected with the engine for applying fuel to the engine at a substantially constant rate when energized by the supply voltage;

starter means connected with the engine for cranking the engine at an output speed directly related to the supply voltage when energized from the power source;

means including a starter switch connected between the starter means and the power source for selectively energizing the starter means with the supply voltage to crank the engine;

timing generator means connected with the engine for producing timing pulses having a frequency directly related to the output speed of the engine;

cranking oscillator means including oscillator control means and oscillator switching means connected with the starter means, the oscillator control means developing a control voltage which varies in a first directional sense at a first excursion rate while the oscillator switching means is in a first state and which varies in a second directional sense at a second excursion rate while the oscillator switching means is in a second state, the oscillator switching means assuming the second state when the control voltage reaches a first control level in the first directional sense and assuming the first state when the control voltage reaches a second control level in the second directional sense, the oscillator switching means producing cranking pulses which are initiated when the oscillator switching means assumes one of the first and second states and which are terminated when the oscillator switching means assumes the other of the first and second states thereby to define the frequency of the cranking pulses as a direct function of the first and second excursion rates of the control voltage, the oscillator control means including voltage detector means connected with the power source for regulating at least one of the first and second excursion rates of the control voltage as an inverse function of the supply voltage so that the frequency of the cranking pulses is inversely related to the supply voltage when the energy capacity of the power source is below normal; and

means connected with the timing generator means and the cranking oscillator means and connected between the fuel injector and the power source for energizing the fuel injector with the supply voltage for a predetermined time period in response to each of the timing pulses and each of the cranking pulses so that the amount of fuel applied to the engine during cranking is compensated for variations in the supply voltage.

9. In an internal combustion engine, the combination comprising:

a power source for providing electrical energy at a supply voltage;

means including at least one voltage responsive fuel injector connected with the engine for applying fuel to the engine at a substantially constant rate when energized by the supply voltage;

starter means connected with the engine for cranking the engine at an output speed directly related to the supply voltage when energized from the power source;

means including a starter switch connected between the starter means and the power source for selectively energizing the starter means to crank the engine;

timing generator means connected with the engine for producing timing pulses having a frequency directly related to the output speed of the engine;

cranking oscillator means connected with the starter means, the cranking oscillator means including oscillator switching means responsive to a control voltage when the starter means is actuated to switch to a set state as the control voltage decreases to a lower control level and to switch to a reset state as the control voltage increases to an upper control level, the oscillator switching means producing cranking pulses which are initiated when the oscillator swItching means assumes one of the set and reset states and which are terminated when the oscillator switching means assumes the other of the set and reset states, the cranking oscillator means further including oscillator control means for applying a control voltage to the oscillator switching means, the oscillator control means including a capacitor for defining the control voltage thereacross, charging means connected to the capacitor for charging the capacitor at a charge rate when the oscillator switching means is in the reset state, and discharging means connected to the capacitor for discharging the capacitor at a discharge rate when the oscillator switching means is in both the set and reset states, the charge rate greater than the discharge rate so that the control voltage increases at a positive excursion rate when the oscillator switching means is in the reset state and decreases at a negative excursion rate when the oscillator switching means is in the set state, the positive excursion rate determined by the charge rate less the discharge rate and the negative excursion rate determined by the discharge rate thereby to define the frequency of the cranking pulses as a direct function of the positive and negative excursion rates of the control voltage, the discharging means including voltage detector means connected with the power source for regulating the discharge rate as an inverse function of the supply voltage so that the frequency of the cranking pulses is inversely related to the supply voltage; and

means connected with the timing generator means and with the cranking oscillator means and connected between the fuel injector and the power source for energizing the fuel injector with the supply voltage for a predetermined time period in response to each of the timing pulses and each of the cranking pulses so that the amount of fuel applied to the engine during cranking is compensated for variations in the supply voltage.

10. In an internal combustion engine system, the combination comprising:

a power source for providing a supply voltage;

fuel injection means connected with the engine for applying fuel to the engine at a substantially constant rate when energized from the power source;

starter means connected with the engine for cranking the engine at an output speed directly related to the supply voltage when energized from the power source;

means including a starter switch connected between the starter means and the power source for selectively energizing the starter means with the supply voltage to crank the engine;

timing pulse generating means connected with the engine for producing timing pulses having a frequency directly related to the output speed of the engine;

cranking pulse generating means connected with the starter means, the cranking pulse generating means including switching means responsive to a control voltage when the starter means is in the actuated condition to switch to a set state as the control voltage decreases to a lower control level and to switch to a reset state as the control voltage increases to an upper control level, the switching means producing cranking pulses which are initiated when the switching means assumes one of the set and reset states and which are terminated when the switching means assumes the other of the set and reset states, the cranking pulse generating means further including control means for applying a control voltage to the switching means, the control means including a capacitor for defining the control voltage thereacross, charging means connected to the capacitor for charging the capacitor at a constant charge rate when the switching means is in the reset state, and discharging means connected to the capacitor for discharging the capacitor at a constant discharge rate when the switching means is in both the set and reset states, the charge rate greater than the discharge rate so that the control voltage increases at a positive excursion rate when the switching means is in the reset state and decreases at a negaTive excursion rate when the switching means is in the set state, the positive excursion rate defined by the charge rate less the discharge rate and the negative excursion rate defined by the discharge rate thereby to define the frequency of the cranking pulses as a direct function of the positive and negative excursion rates of the control voltage, the discharging means including voltage detector means connected with the power source for regulating the discharge rate as an inverse function of the supply voltage so that the frequency of the cranking pulses is inversely related to the supply voltage;

control pulse generating means connected with the timing pulse generating means and with the cranking pulse generating means for producing control pulses in response to the occurrence of the timing pulses and the cranking pulses, the control pulse generating means including transducer means connected with the engine for determining the duration of the control pulses as a function of at least one engine operating parameter; and

means connected with the control pulse generating means and connected between the fuel injection means and the power source for energizing the fuel injection means from the power source for the duration of each of the control pulses so that the amount of fuel applied to the engine is increased during cranking and is compensated for variations in the supply voltage.