Methods and devices for determining a correction value for a measured segment time
View Patent ↗A method and device for determining a correction value for a measured segment time, which a shaft of an internal combustion engine, in particular a crankshaft, needs in order to rotate about a defined angular range, evaluate the following relationship in order to determine correction values for individual cylinders: AZ n =[( TG n −TG 0 )−( n/z )*( TG 0′ −TG 0 )]/[ TG 0 +( n/z )*( TG 0′ −TG 0 )], where z is the number of cylinders of the internal combustion engine, n is the number of the cylinder currently under consideration, TG n is the measured segment time of the cylinder with the number n, TG 0 is the measured segment time of a reference segment of a reference cylinder, TG 0′ is the segment time of the reference segment of the reference cylinder measured two crankshaft rotations after the segment time TG 0 , and AZ n is a correction value for the segment time of the cylinder with the number n.
1. A method for determining a correction value for a measured segment time, which a shaft of an internal combustion engine needs in order to rotate about a defined angular range, comprising the step of:
in determining the correction value, the following relationship is evaluated:
AZ n =[( TG n −TG 0 )−( n/z )*( TG 0′ −TG 0 )]/[ TG 0 +( n/z )*( TG 0′ −TG 0 )]
wherein
z is the number of cylinders of the internal combustion engine,
n is the number of the cylinder currently under consideration,
TG n is the measured segment time of the cylinder with the number n,
TG 0 is the measured segment time of a reference segment of a reference cylinder,
TG 0′ is the segment time of the reference segment of the reference cylinder measured two crankshaft rotations after the segment time TG 0 , and
AZ n is a correction value for the segment time of the cylinder with the number n.
2. The method according to claim 1 , wherein corrected segment times (TK n ) are determined by means of the following relationship:
TK n =TG n *(1 −AZ n ) or
TK n =TB n *(1 −BZ n ).
3. The method according to claim 1 , wherein the corrected segment times (TK n ) are determined by means of the following relationship:
TK n =TG n *(1 −AZM n ) or
TK n =TB n *(1 −BZM n ),
wherein AZM n or BZM n are averaged correction values.
4. The method according to claim 3 , wherein the averaged correction values AZM n or BZM n are determined by calculating a sliding average by means of the relationship
AZM n =AZM n-1 *(1 −MITKO )+ AZ n *MITKO or
BZM n =BZM n-1 *(1 −MITKO )+ BZ n *MITKO
wherein MITKO represents a selectable averaging constant with a value range between zero and one.
5. The method according to claim 1 , wherein the correction value AZ n or BZ n and/or the averaged correction value AZM n or BZM n is preset to an initialization value, preferably to zero, if no correction value or no suitable correction value AZ n or BZ n and/or no suitable averaged correction value AZM n or BZM n is available.
6. The method according to claim 1 , wherein the correction value AZ n or BZ n and/or the averaged correction value AZM n or BZM n upon a start of engine operation is set to the last determined and stored correction value AZ n or BZ n and/or the last determined and stored averaged correction value AZM n or BZM n , and wherein correction of the segment times is carried out only after a predetermined number ZS of steps for calculating correction values AZ n or BZ n and/or averaged correction values AZM n or BZM n .
7. The method according to claim 4 , wherein the correction value AZ n or BZ n and/or the averaged correction value AZM n or BZM n upon a start of engine operation is set to the last determined and stored correction value AZ n or BZ n and/or the last determined and stored averaged correction value AZM n or BZM n , and wherein correction of the segment times is carried out only after a predetermined number ZS of steps for calculating correction values AZ n or BZ n and/or averaged correction values AZM n or BZM n , and wherein the predetermined number ZS of steps is inversely proportional to the averaging constant MITKO.
8. The method according to claim 1 , wherein the shaft is a crankshaft.
9. A method for determining a correction value for a measured segment time, which a shaft of an internal combustion engine, in particular a crankshaft, needs in order to rotate about a defined angular range, comprising the step of:
in determining the correction value, the following relationship is evaluated:
BZ n =[( TB n −TB 0 )−(2 n/z )*( TB 0′ −TB 0 )]/[ TB 0 +(2 n/z )*( TB 0′ −TB 0 )],
wherein
z is the number of cylinders of the internal combustion engine,
n is the number of the segment currently under consideration,
TB n is the measured segment time of the segment with the number n,
TB0 is the measured segment time of a reference segment,
TB0′ is the segment time of the reference segment measured one crankshaft rotation after the segment time TG 0 , and
BZ n is a correction value for the segment time of the segment with the number n.
10. The method according to claim 9 , wherein corrected segment times (TK n ) are determined by means of the following relationship:
TK n =TG n *(1 −AZ n ) or
TK n =TB n *(1 −BZ n ).
11. The method according to claim 9 , wherein the corrected segment times (TK n ) are determined by means of the following relationship:
TK n =TG n *(1 −AZM n ) or
TK n =TB n *(1 −BZM n ),
wherein AZM n or BZM n are averaged correction values.
12. The method according to claim 11 , wherein the averaged correction values AZM n or BZM n are determined by calculating a sliding average by means of the relationship
AZM n =AZM n-1 *(1 −MITKO )+ AZ n *MITKO or
BZM n =BZM n-1 *(1 −MITKO )+ BZ n *MITKO
wherein MITKO represents a selectable averaging constant with a value range between zero and one.
13. The method according to claim 9 , wherein the correction value AZ n or BZ n and/or the averaged correction value AZM n or BZM n is preset to an initialization value, preferably to zero, if no correction value or no suitable correction value AZ n or BZ n and/or no suitable averaged correction value AZM n or BZM n is available.
14. The method according to claim 9 , wherein the correction value AZ n or BZ n and/or the averaged correction value AZM n or BZM n upon a start of engine operation is set to the last determined and stored correction value AZ n or BZ n and/or the last determined and stored averaged correction value AZM n or BZM n , and wherein correction of the segment times is carried out only after a predetermined number ZS of steps for calculating correction values AZ n or BZ n and/or averaged correction values AZM n or BZM n .
15. The method according to claim 11 , wherein the correction value AZ n or BZ n and/or the averaged correction value AZM n or BZM n upon a start of engine operation is set to the last determined and stored correction value AZ n or BZ n and/or the last determined and stored averaged correction value AZM n or BZM n , and wherein correction of the segment times is carried out only after a predetermined number ZS of steps for calculating correction values AZ n or BZ n and/or averaged correction values AZM n or BZM n , and wherein the predetermined number ZS of steps is inversely proportional to the averaging constant MITKO.
16. The method according to claim 9 , wherein the shaft is a crankshaft.
17. A device for determining a correction value for a measured segment time, which a shaft of an internal combustion engine needs in order to rotate about a defined angular range, the device comprises means to determine the correction value by evaluating the following relationship:
AZ n =[( TG n −TG 0 )−( n/z )*( TG 0′ −TG 0 )]/[ TG 0 +( n/z )*( TG 0′ −TG 0 )],
wherein
z is the number of cylinders of the internal combustion engine,
n is the number of the cylinder currently under consideration,
TG n is the measured segment time of the cylinder with the number n,
TG0 is the measured segment time of a reference segment of a reference cylinder,
TG 0′ is the segment time of the reference segment of the reference cylinder measured two crankshaft rotations after the segment time TG 0 , and
AZ n is a correction value for the segment time of the cylinder with the number n.
18. The device according to claim 17 , comprising means to determine the corrected segment times (TK n ) by means of the following relationship:
TK n =TG n *(1 −AZ n ) or
TK n =TB n *(1 −BZ n ).
19. The device according to claim 17 , comprising means to determine the corrected segment times TK n by means of the following relationship:
TK n =TG n *(1 −AZM n ) or
TK n =TB n *(1 −BZM n ),
wherein AZM n or BZM n are averaged correction values.
20. The device according to claim 19 , comprising means to determine the averaged correction values AZM n or BZM n by calculating a sliding average by means of the relationship
AZM n =AZM n-1 *(1 −MITKO )+ AZ n *MITKO or
BZM n =BZM n-1 *(1 −MITKO )+BZ n *MITKO
wherein MITKO represents a selectable averaging constant with a value range between zero and one.
21. The device according to claim 17 , comprising means tp preset the correction value AZ n or BZ n and/or the averaged correction value AZM n or BZM n to an initialization value, preferably to zero, if no correction value or no suitable correction value AZ n or BZ n and/or no suitable averaged correction value AZM n or BZM n is available.
22. The device according to claim 17 , comprising means to set the correction value AZ n or BZ n and/or the averaged correction value AZM n or BZM n upon a start of engine operation to the last determined and stored correction value AZ n or BZ n and/or the last determined and stored averaged correction value AZM n or BZM n , and means to carry out the correction of the segment times only after a predetermined number ZS of steps for calculating correction values AZ n or BZ n and/or averaged correction values AZM n or BZM n .
23. The device according to claim 20 , comprising means to set the correction value AZ n or BZ n and/or the averaged correction value AZM n or BZM n upon a start of engine operation to the last determined and stored correction value AZ n or BZ n and/or the last determined and stored averaged correction value AZM n or BZM n , and means to carry out the correction of the segment times only after a predetermined number ZS of steps for calculating correction values AZ n or BZ n and/or averaged correction values AZM n or BZM n , wherein the predetermined number ZS of steps is inversely proportional to the averaging constant MITKO.
24. The device according to claim 17 , wherein the shaft is a crankshaft.
25. A device for determining a correction value for a measured segment time, which a shaft of an internal combustion engine needs in order to rotate about a defined angular range, comprising means to determine the correction value by evaluating the following relationship:
BZ n =[( TB n −TB 0 )−(2 n/z )*( TB 0′ −TB 0 )]/[ TB 0 +(2 n/z )* TB 0′ −TB 0 )],
wherein
z is the number of cylinders of the internal combustion engine,
n is the number of the segment currently under consideration,
TBn is the measured segment time of the segment with the number n,
TB0 is the measured segment time of a reference segment,
TB0′ is the segment time of the reference segment measured one crankshaft rotation after the segment time TG0, and
BZ n is a correction value for the segment time of the segment with the number n.
26. The device according to claim 25 , comprising means to determine the corrected segment times (TK n ) by means of the following relationship:
TK n =TG n *(1 −AZ n ) or
TK n =TB n *(1 −BZ n ).
27. The device according to claim 25 , comprising means to determine the corrected segment times TK n by means of the following relationship:
TK n =TG n *(1 −AZM n ) or
TK n =TB n *(1 −BZM n ),
wherein AZM n or BZM n are averaged correction values.
28. The device according to claim 27 , comprising means to determine the averaged correction values AZM n or BZM n by calculating a sliding average by means of the relationship
AZM n =AZM n-1 *(1 −MITKO )+ AZ n *MITKO or
BZM n =BZM n-1 *(1 −MITKO )+ BZ n *MITKO
wherein MITKO represents a selectable averaging constant with a value range between zero and one.
29. The device according to claim 25 , comprising means tp preset the correction value AZ n or BZ n and/or the averaged correction value AZM n or BZM n to an initialization value, preferably to zero, if no correction value or no suitable correction value AZ n or BZ n and/or no suitable averaged correction value AZM n or BZM n is available.
30. The device according to claim 25 , comprising means to set the correction value AZ n or BZ n and/or the averaged correction value AZM n or BZM n upon a start of engine operation to the last determined and stored correction value AZ n or BZ n and/or the last determined and stored averaged correction value AZM n or BZM n , and means to carry out the correction of the segment times only after a predetermined number ZS of steps for calculating correction values AZ n or BZ n and/or averaged correction values AZM n or BZM n .
31. The device according to claim 28 , comprising means to set the correction value AZ n or BZ n and/or the averaged correction value AZM n or BZM n upon a start of engine operation to the last determined and stored correction value AZ n or BZ n and/or the last determined and stored averaged correction value AZM n or BZM n , and means to carry out the correction of the segment times only after a predetermined number ZS of steps for calculating correction values AZ n or BZ n and/or averaged correction values AZM n or BZM n , wherein the predetermined number ZS of steps is inversely proportional to the averaging constant MITKO.
32. The device according to claim 25 , wherein the shaft is a crankshaft.