US 4,936,277 A · System for monitoring and/or controlling multiple cylinder engine performance

Abstract

Engine crankshaft speed signal, comprising pulses produced by a toothed wheel and sensor, has portions monitored to develop separate instantaneous cylinder associated power output vector signals for each engine cylinder. Engine knock is detected by comparing actual variations in each cylinder power signal with expected variations. Each vector cylinder power signal is multiplied by different first and second weighting vector signals to provide first and second scalar signals indicative of cylinder performance with respect to first and second different cylinder performance criteria, respectively. These scaler signals are compared to each other and a balancing of cylinder power is achieved by adjusting the amount of fuel delivered to each individual cylinder. Preferably, fuel adjustment is implemented such that the average fuel delivered to the cylinders prior to adjustment, determined in accordance with exhaust pollution level, will equal the average fuel delivered after adjustment. Knock detection is provided without using any additionall knock sensor since the existing crankshaft speed sensor signal is used. The generated individual cylinder power vector signals, by use of different weighting vectors, allow detection of several different faults or other performance criteria for each cylinder. Balancing cylinder power is achieved while fuel consumption is maintained in accordance with desired exhaust pollution levels.

Claims22

Dependent claims

For an engine having multiple separate cylinders each intended for sequentially providing, during a cylinder-associated power cycle separate from the power cycles associated with other cylinders, a driving force to common driven mechanical member, a system for monitoring and/or controlling engine performance comprising:

means for developing separate power output signals for each of said cylinders, each of said power output signals representative of and associated with the driving force provided by an associated cylinder to the driven member and having a magnitude indicative of such provided driving force attributable to said associated cylinder, said magnitude varying over the associated power output cycle;
first means for multiplying each of said power output signals by a first weighting factor to obtain a first product signal, associated with each cylinder, representative of each cylinder's performance over its associated power cycle;
first means for comparing each of said cylinder-associated first product signals to a selected reference level to determine each cylinder's performance with respect to a first performance criteria;
second means for multiplying each of said power output signals by a second weighting factor, different from said first weighting factor, to obtain a second product signal, associated with each cylinder, representative of each cylinder's performance over its associated power cycle;
and
second means for comparing each of said cylinder-associated second product signals to a second selected reference level to determine each cylinder's performance with respect to a second performance criteria different from said first performance criteria;
whereby the same output power signals associated with each cylinder are used for the monitoring of two different performance criteria of said cylinders.

4 more elements

For an engine having multiple separate cylinders each sequentially providing a driving force to a common mechanical member, a system for controlling engine performance comprising:

means for delivering a predetermined average amount of fuel to all of said cylinders in accordance with at least a predetermined criteria;
means for monitoring individual cylinder power performance and developing associated cylinder power performance signals indicative of each cylinder's performance in developing power to be transferred to said member;
means for correcting the amount of fuel delivered to each cylinder, which is determined by cylinder-associated fuel metering control signals, in accordance with said cylinder-associated power performance signals, such that each cylinder's performance is balanced (adjusted) with respect to other cylinders so that each cylinder's performance more closely matches that of another cylinder;
and
means for maintaining the average amount of fuel delivered to all of said cylinders at said predetermined average amount while cylinder power balancing is achieved by said correcting means.

2 more elements

For an engine having multiple separate cylinders each sequentially providing a driving force to a common mechanical member, a system for controlling engine performance comprising:

means for monitoring individual cylinder power performance in developing associated cylinder power performance signals indicative of each cylinder's performance in developing power to be transferred to said member;
and
means for correcting the amount of fuel delivered to each individual cylinder, which is determined by cylinder-associated fuel metering control signals, in accordance with said power performance signals, such that each cylinder's performance is balanced (adjusted) with respect to other cylinders so that each cylinder's power performance more closely matches that of another cylinder;
wherein said correcting means achieves cylinder balance by comparing the power performance signal of a first cylinder to the power performance signal of a second cylinder and determining said fuel metering control signals for said first and second cylinders in accordance with the difference between said compared power performance signals,
means for delivering a predetermined average amount of fuel to all of said cylinders in accordance with a predetermined criteria, and
means for maintaining the average amount of fuel delivered to all of said cylinders at said predetermined average amount while cylinder power balancing is achieved by said correcting means.

3 more elements

For an engine having multiple separate cylinders each sequentially providing a driving force to a common mechanical member, a system for monitoring and/or controlling engine performance comprising:

sensor means for monitoring the position of said driven member and developing a speed-indicative signal indicative of and varying in accordance with the speed at which said driven member is driven by said multiple cylinders;
means for monitoring a predetermined portion of said speed-indicative signal, said monitored portion generated in association with and during an expected power cycle produced by a first one of said cylinders and prior to an expected next sequential power cycle of another one of said cylinders;
and
means for developing a signal indicative of the occurrence of knock in said first one of said cylinders by determining when variations of said monitored portion of said speed-indicative signal match expected variations of said monitored speed-indicative signal which exist when knock in said first cylinder is present.

1 more element

Dependencies are inferred from the claim text.

System for monitoring and/or controlling multiple cylinder engine performance

Life of this patent

System for monitoring and/or controlling multiple cylinder engine performance

Life of this patent

Abstract

Claims22