US 4,300,503 A · Process and system for computation and adjustment of optimum ignition advance

Abstract

A novel process and system for computing and adjusting the optimum ignition advance in an internal combustion engine wherein knocking is detected by means of an accelerometer rigidly fastened to the cylinder head of the engine. An output from the accelerometer is integrated, converted into digital form, and processed by processing circuits to derive an average value C proportional to n preceding knocks and two comparison thresholds S.sub.1 and S.sub.2, each a linear function of the preceding average value C. The accelerometer output integrated and converted into digital form is compared with each of these thresholds and the existence of a preknocking or audible knocking value is deduced and then used to act on the programmed electronic ignition advance.

Claims12

Dependent claims

A process for the computation and adjustment of the optimum ignition advance for an internal combustion engine by means of a system for detection of knocking using a sensor such as an accelerometer rigidly attached to the cylinder head of the engine, comprising:

integrating an accelerometer signal inside a given window;
converting the integrated accelerometer signal into digital form;
computing an average value C proportional to the n preceding knocks;
computing two comparison thresholds S.sub.1 and S.sub.2, each a linear function of the previously computed average value C;
comparing the accelerometer value integrated in digital form with each of the thresholds S.sub.1 and S.sub.2 ;
deducing the existence of absence of a preknocking and/or audible knocking value;
and
using said value to act on the programmed advance of the electronic ignition.

5 more elements

A knocking detection system for the computation and adjustment of the optimum ignition advance for an internal combustion engine, comprising:

an accelerometer rigidly attached to the cylinder head of the engine for detecting knocking:
analog processing means for processing a knocking signal read from the accelerometer, said analog processing means comprising,
an integrator for integrating the accelerometer knocking signal,
logic means for controlling the operation of the integrator,
an analog-digital converter for digitalizing the integrator output, and
a microcomputer including a sequencer, a stage for computation of an average value C proportional to n preceding knocks, two stages for computation of comparison thresholds (S.sub.1, S.sub.2) which are each a linear function of the average value C computed previously, and means for deducing the presence or absence of a preknocking and/or audible knocking value.

3 more elements

Dependencies are inferred from the claim text.

Process and system for computation and adjustment of optimum ignition advance

Life of this patent

Process and system for computation and adjustment of optimum ignition advance

Life of this patent

Abstract

Claims12