Alcohol discriminator and fuel control for an internal combustion engine fueled with alcohol-gasoline fuel mixtures

• US 5,179,926 A
• Filed: 02/18/1992
• Issued: 01/19/1993
• Est. Priority Date: 02/18/1992
• Status: Expired due to Fees

• Current Assignee: General Motors Corporation (Motors Liquidation Co. GUC Trust)
• Original Assignee: General Motors Corporation (Motors Liquidation Co. GUC Trust)
• Inventors: Ament, Frank
• Primary Examiner(s): ARGENBRIGHT, TONY MICHAEL
• Application Number:
  US07/836,579
• Time in Patent Office: 336 Days
• Field of Search: 123/1 A, 123/494, 123/575, 73/61.43, 73/61.44, 73/61.49
• US Class Current: 123/494
• CPC Class Codes: F02D 19/084 Blends of gasoline and alcohols, e.g. E85
• CPC Class Codes: F02D 19/087 with determination of densities, viscosities, composition, concentration or mixture ratios of fuels
• CPC Class Codes: F02D 2200/0611 Fuel type, fuel composition or fuel quality
• CPC Class Codes: F02D 41/0025 Controlling engines characterised by use of non-liquid fuels, pluralities of fuels, or non-fuel substances added to the combustible mixtures
• CPC Class Codes: G01N 27/06 of a liquid involving electrolysis G01N27/26
• CPC Class Codes: G01N 33/2852 alcohol/fuel mixtures
• CPC Class Codes: Y02T 10/30 Use of alternative fuels, e.g. biofuels

Abstract

An apparatus for discriminating between different types of alcohol contained in alcohol-gasoline fuel mixtures, such as methanol or ethanol, and a fueling system for controlling the quantity of alcohol-gasoline fuel mixture delivered to an internal combustion engine in accordance with type of alcohol determined to be present in the fuel mixture are described. The resistivity of the fuel mixture delivered to the engine is measured using a fuel resistance sensor. Based upon the measured resistivity, the type of alcohol contained in the fuel mixture is determined and indicated. The fuel system then adjusts the quantity of the fuel mixture delivered to the engine based upon the indicated type of alcohol and the sensed alcohol concentration in the fuel mixture.

Claims

1. A discriminator apparatus for identifying the type of alcohol contained in an alcohol-gasoline fuel mixture delivered to an internal combustion engine, the discriminator apparatus comprising:

a sensor for measuring the electrical resistivity of the fuel mixture and for developing a signal indicative of the fuel mixture resistivity;

means responsive to the signal developed by the sensor for determining the type of alcohol contained in the fuel mixture;

means for providing an output signal indicative of the type of alcohol determined to be present in the fuel mixture.

2. A discriminator apparatus for identifying the type of alcohol contained in an alcohol-gasoline fuel mixture delivered to an internal combustion engine, where the alcohol is from the group consisting of ethanol and methanol, the discriminator apparatus comprising;

a resistive sensor for measuring the electrical resistivity of the fuel mixture and for developing a resistance signal having a value indicative of the fuel mixture resistivity;

means for deriving a threshold resistance value;

means for comparing the value of the resistance signal with the threshold resistance value;

means for providing an output signal indicating that ethanol is contained in the fuel mixture when value of the resistance signal is greater than the threshold resistance value and indicating that methanol is contained in the fuel mixture when the value of the resistance signal is less than the threshold resistance value.

3. The discriminator apparatus as described in claim 2, wherein the threshold resistive value is a predetermined constant value.

4. The discriminator apparatus as described in claim 2, which further includes a capacitance sensor for measuring the dielectric constant of the fuel mixture and for developing a capacitance signal having a value indicative of the fuel mixture dielectric constant, wherein the threshold resistive value is derived based upon the value of the capacitance signal.

5. The discriminator apparatus as described in claim 4, which further includes means for indicating that the fuel mixture contains ethanol when the value of the capacitance signal exceed a predetermined threshold capacitance value.

6. The discriminator apparatus as described in claim 2, which further includes:

a capacitance sensor for measuring the dielectric constant of the fuel mixture and for developing a capacitance signal having a value indicative of the fuel mixture dielectric constant;

a temperature sensor for measuring the temperature of the fuel mixture and for developing a temperature signal having a value indicative of the temperature of the fuel mixture delivered to the engine, wherein the threshold resistance value is derived based upon the values of the capacitance signal and the temperature signal.

7. The discriminator apparatus as described in claim 6, which further includes means for indicating that fuel mixture contains ethanol when the value of the capacitance signal exceed a predetermined threshold capacitance value.

8. A fuel control system for an internal combustion engine operated on an alcohol-gasoline fuel mixture, the control system comprising:

sensor means for identifying the type and relative concentration of alcohol contained in the alcohol-gasoline fuel mixture;

means for controlling the quantity of fuel delivered to the engine based upon the identified type and relative concentration of alcohol in the fuel mixture.

9. A fuel control system for an internal combustion engine operated on an alcohol-gasoline fuel mixture, the control system comprising:

a sensor for identifying the type of alcohol contained in the alcohol-gasoline fuel mixture;

means for determining the relative concentration of alcohol to gasoline in the fuel mixture in accordance with identified type of alcohol in the fuel mixture; and

means for controlling the quantity of fuel delivered to the engine based upon the identified type and concentration of alcohol in the fuel mixture.

10. The fuel control system described in claim 9, wherein the type of alcohol contained in the fuel mixture is one from a group consisting of ethanol and methanol.

11. A fuel control system for an internal combustion engine operated on an alcohol-gasoline fuel mixture, the fuel control system comprising:

a resistive sensor for measuring the resistivity of the fuel mixture and for developing a resistance signal indicative of fuel mixture resistivity;

a capacitive sensor for measuring the dielectric constant of the fuel mixture and for developing a capacitance signal indicative of the fuel mixture dielectric constant;

means responsive to the resistance and capacitance signals for determining the type and concentration of alcohol in the fuel mixture;

means for controlling the quantity of fuel mixture delivered to the engine in accordance with the determined type and concentration of alcohol in the fuel mixture.

12. The fuel control system described in claim 11, wherein the type of alcohol contained in the fuel mixture is one from a group consisting of ethanol and methanol.

13. The fuel control system described in claim 11, wherein the relative concentration of the alcohol to gasoline in the fuel mixture is determined in accordance with the dielectric constant of the fuel mixture and the type of alcohol determined to be present in the fuel mixture.