Failsafe drive-by-wire engine controller

• US 4,640,248 A
• Filed: 12/23/1985
• Issued: 02/03/1987
• Est. Priority Date: 12/23/1985
• Status: Expired due to Term

• Current Assignee: General Motors Corporation (General Motors Company)
• Original Assignee: General Motors Corporation (General Motors Company)
• Inventors: Stoltman, Donald D.
• Primary Examiner(s): Cuchlinski, Jr., William A.
• Application Number:
  US06/812,901
• Time in Patent Office: 407 Days
• Field of Search: 123/359, 123/361, 123/399, 123/479
• US Class Current: 123/399
• CPC Class Codes: F02D 11/106 Detection of demand or actuation

Abstract

A drive-by-wire engine control system in which the engine is set to an idle operating mode when the force applied to the accelerator pedal is zero even though the accelerator pedal is in an off-idle position.

Claims

1. A control system for a vehicle internal combustion engine having an intake space into which air and fuel are supplied, comprising in combination:

an accelerator pedal biased to an engine idle position and operable to an engine off-idle position in response to a force applied thereto;

position sensing means for sensing the position of the accelerator pedal;

force sensing means for sensing the force applied to the accelerator pedal; and

means responsive to the force applied to the accelerator pedal sensed by the force sensing means for supplying an air and fuel mixture to the engine in accord with the accelerator pedal position sensed by the position sensing means when the force applied to the accelerator pedal is greater than zero and in accord with an engine idle schedule when the force applied to the accelerator pedal is zero, whereby the engine operation is maintained at idle when the force applied to the accelerator pedal is zero even though the accelerator pedal position remains in an off-idle position.

2. A control system for a vehicle internal combustion engine having an intake space into which air and fuel are supplied, comprising in combination:

an accelerator pedal biased to an engine idle position and operable to an engine off-idle position in response to a force applied thereto;

position sensing means for sensing the position of the accelerator pedal;

force sensing means for sensing the force applied to the accelerator pedal;

fuel supply means responsive to the force applied to the accelerator pedal sensed by the force sensing means for (A) supplying a fuel to the intake space in accord with the accelerator pedal position sensed by the position sensing means when the force applied to the accelerator pedal is greater than zero and (B) supplying an idle fuel quantity to the intake space when the force applied to the accelerator pedal is zero;

air supply means including a variable position throttle operable to regulate the air flow into the engine intake space; and

means responsive to the fuel supplied to the intake space for positioning the throttle to a position at which the air flow into the intake space results in a desired air and fuel ratio, whereby the engine operation is maintained at idle when the force applied to the accelerator pedal is zero even though the accelerator pedal position remains in an off-idle position.