US5657625A — Apparatus and method for internal combustion engi…

Claim 1

Independent Claim 215 words

A control apparatus for an internal combustion engine having an exhaust purifying catalytic device disposed in an exhaust passage for reducing emission of nitrogen oxides to atmosphere, the exhaust purifying catalytic device being operable to adsorb nitrogen oxides contained in exhaust gas discharged from the internal combustion engine when the engine is in a lean-combustion mode where an air-fuel ratio of an air-fuel mixture supplied to the engine is leaner than a theoretical air-fuel ratio, and to deoxidize adsorbed nitrogen oxides when the internal combustion engine is in a rich-combustion mode where the air-fuel ratio is equal to or richer than the theoretical air-fuel ratio, comprising: adsorption amount estimating means for estimating an adsorption amount of purifying capability reducing substances, which decreases nitrogen oxide adsorbing ability of the exhaust purifying catalytic device, adsorbed by the exhaust purifying catalytic device and for determining whether the estimated adsorption amount has reached a predetermined adsorption amount; and catalyst heating means for removing the purifying capability reducing substances from the exhaust purifying catalytic device by increasing a temperature of the exhaust purifying catalytic device by changing an operating condition of the internal combustion engine so that an exhaust gas temperature increases when said adsorption amount estimating means judges that the estimated adsorption amount has reached the predetermined adsorption amount.

Claim 2

Dependent Claim 215 words

A control apparatus for an internal combustion engine having an exhaust purifying catalytic device disposed in an exhaust passage for reducing emission of nitrogen oxides to atmosphere, the exhaust purifying catalytic device being operable to adsorb nitrogen oxides contained in exhaust gas discharged from the internal combustion engine when the engine is in a lean-combustion mode where an air-fuel ratio of an air-fuel mixture supplied to the engine is leaner than a theoretical air-fuel ratio, and to deoxidize adsorbed nitrogen oxides when the internal combustion engine is in a rich-combustion mode where the air-fuel ratio is equal to or richer than the theoretical air-fuel ratio, comprising: adsorption amount estimating means for estimating an adsorption amount of purifying capability reducing substances, which decreases nitrogen oxide adsorbing ability of the exhaust purifying catalytic device, adsorbed by the exhaust purifying catalytic device and for determining whether the estimated adsorption amount has reached a predetermined adsorption amount; and catalyst heating means for removing the purifying capability reducing substances from the exhaust purifying catalytic device by increasing a temperature of the exhaust purifying catalytic device by changing an operating condition of the internal combustion engine so that an exhaust gas temperature increases when said adsorption amount estimating means judges that the estimated adsorption amount has reached the predetermined adsorption amount.

Claim 3

Dependent Claim 56 words

A control apparatus according to claim 1, wherein said adsorption amount estimating means includes fuel amount accumulating means for accumulating fuel consumption of the internal combustion engine, and judges that the estimated adsorption amount has reached the predetermined adsorption amount when the accumulated fuel consumption calculated by said fuel amount accumulating means reaches a predetermined amount.

Claim 4

Dependent Claim 55 words

A control apparatus according to claim 2, wherein the internal combustion engine is supplied with fuel from a fuel injection valve driven by a pulse-shaped driving current, said fuel amount accumulating means accumulates a pulse width of the driving current, and said accumulated fuel consumption is calculated on the basis of the accumulated pulse width.

Claim 5

Dependent Claim 30 words

A control apparatus according to claim 2, wherein said fuel amount accumulating means accumulates the fuel consumption only when the internal combustion engine is being operated in the lean-combustion mode.

Claim 6

Dependent Claim 46 words

A control apparatus according to claim 2, further including: catalyst temperature detecting means for detecting the temperature of the exhaust purifying catalytic device; wherein said fuel amount accumulating means accumulates the fuel consumption only when the catalytic device temperature is not higher than a predetermined temperature.

Claim 7

Dependent Claim 57 words

A control apparatus according to claim 1, wherein said adsorption amount estimating means includes travel distance accumulating means for accumulating a travel distance of a vehicle on which the internal combustion engine is mounted, and judges that the estimated adsorption amount has reached the predetermined adsorption amount when the accumulated vehicle travel distance reaches a predetermined value.

Claim 8

Dependent Claim 55 words

A control apparatus according to claim 1, wherein said adsorption amount estimating means includes intake air amount accumulating means for detecting and accumulating an intake air amount of the internal combustion engine, and judges that the estimated adsorption amount has reached the predetermined adsorption amount when the accumulated intake air amount reaches a predetermined value.

Claim 9

Dependent Claim 56 words

A control apparatus according to claim 1, wherein said catalyst heating means burns fuel near the exhaust purifying catalytic device by changing the operating condition of the internal combustion engine so that fuel and air are supplied into the exhaust gas, by which the exhaust purifying catalytic device is heated by increasing the exhaust gas temperature.

Claim 10

Dependent Claim 107 words

A control apparatus according to claim 8, wherein said catalyst heating means includes air-fuel ratio control means for controlling the air-fuel ratio of the air-fuel mixture supplied to the internal combustion engine, and said air-fuel ratio control means controls the air-fuel ratio in part of cylinders of the internal combustion engine to a value lower than the theoretical air-fuel ratio to perform rich-combustion operation in said part of cylinders and controls the air-fuel ratio in the remaining cylinders to a value higher than the theoretical air-fuel ratio to perform lean-combustion operation in said remaining cylinders, by which the fuel and air are supplied into the exhaust gas.

Claim 11

Dependent Claim 42 words

A control apparatus according to claim 9, wherein said air-fuel ratio control means makes an average air-fuel ratio of all the cylinders of the internal combustion engine substantially equal to the theoretical air-fuel ratio when the exhaust purifying catalytic device is heated.

Claim 12

Dependent Claim 57 words

A control apparatus according to claim 9, wherein said air-fuel ratio control means includes catalyst temperature detecting means for detecting a temperature of the exhaust purifying catalytic device, and controls the air-fuel ratio so that the catalytic device temperature is kept at a predetermined temperature after the detected catalytic device temperature has increased to the predetermined temperature.

Claim 13

Dependent Claim 66 words

A control apparatus according to claim 11, wherein said air-fuel ratio control means makes an average air-fuel ratio of all the cylinders of the internal combustion engine substantially equal to the theoretical air-fuel ratio before the detected catalytic device temperature reaches said predetermined temperature, and corrects the average air-fuel ratio to a side richer than the theoretical air-fuel ratio after the predetermined temperature has been reached.

Claim 14

Dependent Claim 40 words

A control apparatus according to claim 9, wherein the internal combustion engine is a V-type engine, and said part of cylinders are on one bank side of said V-type engine, and said remaining cylinders are on the other bank side.

Claim 15

Dependent Claim 65 words

A control apparatus according to claim 9, wherein said air-fuel ratio control means includes ignition timing control means for controlling ignition timing of the internal combustion engine, and said ignition timing control means retards the ignition timing of said part of cylinders in which the rich-combustion operation is performed and advances the ignition timing of said remaining cylinders in which the lean-combustion operation is performed.

Claim 16

Dependent Claim 62 words

A control apparatus according to claim 9, wherein said air-fuel ratio control means includes intake air amount regulating means, and said intake air amount regulating means increases an intake air amount of the internal combustion engine when the rich-combustion operation is performed in said part of cylinders of the internal combustion engine and the lean-combustion operation is performed in the remaining cylinders.

Claim 17

Dependent Claim 92 words

A control apparatus according to claim 1, further including: a lockup clutch interposed between the internal combustion engine and an automatic transmission; and clutch control means for changing over said lockup clutch between a connected state in which the engine is connected directly to the automatic transmission and a disconnected state in which the engine is not connected directly to the automatic transmission; wherein said clutch control means makes said lockup clutch disconnected during the time when the temperature of the exhaust purifying catalytic device is raised by said catalyst heating means.

Claim 18

Dependent Claim 56 words

A control apparatus according to claim 1, further including: operating condition detecting means for detecting an operating condition of the internal combustion engine; wherein said catalyst heating means heats the exhaust purifying catalytic device when said operating condition detecting means judges that the internal combustion engine is in a predetermined medium or heavy load operating condition.

Claim 19

Dependent Claim 62 words

A control apparatus according to claim 17, wherein said operating condition detecting means includes exhaust temperature estimating means for estimating an exhaust temperature of the internal combustion engine, and said operating condition detecting means judges that the internal combustion engine is in said predetermined medium or heavy load operating condition when the estimated exhaust temperature is not lower than a predetermined temperature.

Claim 20

Dependent Claim 65 words

A control apparatus according to claim 18, wherein said exhaust temperature estimating means includes load detecting means for detecting a load of the internal combustion engine and rotational speed detecting means for detecting a rotational speed of the internal combustion engine, and said exhaust temperature estimating means estimates said exhaust temperature on the basis of the detected engine load and the detected engine rotational speed.

Claim 21

Dependent Claim 65 words

A control apparatus according to claim 17, further including: time measuring means for accumulatively measuring a time period elapsed during the time when said operating condition detecting means judges that the internal combustion engine is in said predetermined medium or heavy load operating condition, and said catalyst heating means heats the exhaust purifying catalytic device until the counted elapsed time period reaches a predetermined time.

Claim 22

Dependent Claim 47 words

A control apparatus according to claim 20, further including: catalyst temperature detecting means for detecting the temperature of the exhaust purifying catalytic device; wherein said time measuring means accumulatively measures said elapsed time period when the detected catalyst device temperature is not lower than a predetermined temperature.

Claim 23

Dependent Claim 52 words

A control apparatus according to claim 20, wherein said time measuring means starts to accumulatively measure said elapsed time period from a moment when a predetermined delay time has elapsed after said operating condition detecting means judges that the internal combustion engine is in said predetermined medium or heavy load operating condition.

Claim 24

Dependent Claim 94 words

A control apparatus according to claim 1, wherein said adsorption amount estimating means includes storage means for storing the estimated adsorption amount of the purifying capability reducing substances as long as said storage means is connected to a power source and power is supplied from said power source, and said catalyst heating means heats the exhaust purifying catalytic device independently of the estimated adsorption amount when the supply of power from said power source to said storage means is restarted after the power is not supplied from said power source to said storage means.

Claim 25

Dependent Claim 27 words

A control apparatus according to claim 1, wherein said catalyst heating means increases the exhaust gas temperature by changing a burning state of the internal combustion engine.

Claim 26

Dependent Claim 51 words

A control apparatus according to claim 24, wherein said catalyst heating means includes ignition timing correcting means for correcting ignition timing of the internal combustion engine, and said ignition timing correcting means changes the burning state of the internal combustion engine by retarding the ignition timing of the internal combustion engine.

Claim 27

Dependent Claim 54 words

A control apparatus according to claim 25, wherein said catalyst heating means includes intake air amount correcting means for correcting an intake air amount of the internal combustion engine, and said intake air amount correcting means increases the intake air amount during the time when said ignition timing correcting means retards the ignition timing.

Claim 28

Dependent Claim 66 words

A control apparatus according to claim 25, further including: rotational speed detecting means for detecting a rotational speed of the internal combustion engine; and volumetric efficiency detecting means for detecting a volumetric efficiency of the internal combustion engine; wherein said ignition timing correcting means sets a retard amount of the ignition timing on the basis of the detected engine rotational speed and the detected volumetric efficiency.

Claim 29

Dependent Claim 85 words

A control apparatus according to claim 1, wherein said catalyst heating means includes catalyst temperature detecting means for detecting the temperature of the exhaust purifying catalytic device and air-fuel ratio control means for controlling the internal combustion engine so that the internal combustion engine is operated in a rich-combustion mode in which the air-fuel ratio of the air-fuel mixture supplied to the internal combustion engine is equal to or richer than the theoretical air-fuel ratio, when the detected catalytic device temperature reaches a predetermined temperature.

Claim 30

Dependent Claim 126 words

A control apparatus according to claim 1, wherein said catalyst heating means includes air-fuel control means for controlling the internal combustion engine so that the internal combustion engine is operated in a rich-combustion mode in which the air-fuel ratio of the air-fuel mixture supplied to the internal combustion engine is equal to or richer than the theoretical air-fuel ratio, when said adsorption amount estimating means judges that the adsorption amount of the purifying capability reducing substances has reached the predetermined adsorption amount; and secondary air supplying means for supplying secondary air to an upstream side with respect to the exhaust purifying catalytic device in the exhaust passage when the internal combustion engine is controlled so that the internal combustion engine is operated in the rich-combustion mode.

Claim 31

Dependent Claim 51 words

A control apparatus according to claim 29, wherein said catalyst heating means includes catalyst temperature detecting means for detecting the temperature of the exhaust purifying catalytic device, and said secondary air supplying means decreases a supply amount of the secondary air when the detected catalytic device temperature reaches a predetermined temperature.

Claim 32

Dependent Claim 75 words

A control apparatus according to claim 29, further including: rotational speed detecting means for detecting a rotational speed of the internal combustion engine; and volumetric efficiency detecting means for detecting a volumetric efficiency of the internal combustion engine; wherein said air-fuel ratio control means sets the air-fuel ratio during the time the internal combustion engine is operated in the rich-combustion mode on the basis of the detected engine rotational speed and the detected volumetric efficiency.

Claim 33

Dependent Claim 65 words

A control apparatus according to claim 29, further including: rotational speed detecting means for detecting rotational speed of the internal combustion engine; and volumetric efficiency detecting means for detecting a volumetric efficiency of the internal combustion engine; wherein said secondary air supplying means sets a supply amount of the secondary air on the basis of the detected engine rotational speed and the detected volumetric efficiency.

Claim 34

Dependent Claim 26 words

A control apparatus according to claim 1, wherein said catalyst heating means increases the exhaust gas temperature by changing a flow velocity of the exhaust gas.

Claim 35

Dependent Claim 68 words

A control apparatus according to claim wherein said catalyst heating means includes an exhaust throttle valve, installed on a downstream side with respect to the exhaust purifying catalytic device in the exhaust passage, for changing an area of the exhaust passage, and said catalyst heating means changes the flow velocity of the exhaust gas by controlling said exhaust throttle valve so that the exhaust passage area is decreased.

Claim 36

Dependent Claim 59 words

A control apparatus according to claim 33, wherein said catalyst heating means includes catalyst temperature detecting means for detecting the temperature of the exhaust purifying catalytic device and fuel supplying means for supplying fuel to an upstream side with respect to the exhaust purifying catalytic device in the exhaust passage when the detected catalyst temperature reaches a predetermined temperature.

Claim 37

Dependent Claim 112 words

A control apparatus according to claim 1, further including: exhaust pipe length changing means for changing an exhaust passage length from an exhaust port of the internal combustion engine to the exhaust purifying catalytic device so that said exhaust pipe length changing means is controlled in such a manner that, when said adsorption amount estimating means judges that the adsorption amount of the purifying capability reducing substances has reached the predetermined adsorption amount, the exhaust passage length is shorter than that before it is judged that the estimated adsorption amount has reached the predetermined adsorption amount, by which the temperature of exhaust gas supplied to the exhaust purifying catalytic device is increased.

Claim 38

Dependent Claim 153 words

A control apparatus according to claim 36, wherein said exhaust pipe length changing means includes a first exhaust passage forming at least part of the exhaust passage extending from the exhaust port of the internal combustion engine to the exhaust purifying catalytic device, a second exhaust passage disposed in parallel with said first exhaust passage and shorter than said first exhaust passage, and valve means for opening and closing said second exhaust passage; wherein said exhaust heating means closes said second exhaust passage by using said valve means before said adsorption amount estimating means judges that the estimated adsorption amount has reached the predetermined adsorption amount, and drives said valve means to open said second exhaust passage when said adsorption amount estimating means judges that the estimated adsorption amount has reached the predetermined adsorption amount, by which the exhaust gas is supplied to the exhaust purifying catalytic device via said second exhaust passage.

Claim 39

Dependent Claim 23 words

A control apparatus according to claim 36, wherein the exhaust purifying catalytic device is disposed near a body of the internal combustion engine.

Claim 40

Dependent Claim 59 words

A control apparatus according to claim 36, wherein said catalyst heating means includes catalyst temperature detecting means for detecting the temperature of the exhaust purifying catalytic device, and fuel supplying means for supplying fuel to an upstream side with respect to the exhaust purifying catalytic device in the exhaust passage when the detected catalyst temperature reaches a predetermined temperature.

Claim 41

Dependent Claim 213 words

A control apparatus for an internal combustion engine having an exhaust purifying catalytic device disposed in an exhaust passage for reducing emission of nitrogen oxides to atmosphere, the exhaust purifying catalytic device being operable to adsorb nitrogen oxides contained in exhaust gas discharged from the internal combustion engine when the engine is in a lean-combustion mode where an air-fuel ratio of an air-fuel mixture supplied to the engine is leaner than a theoretical air-fuel ratio, and to deoxidize adsorbed nitrogen oxides when the internal combustion engine is in a rich-combustion mode where the air-fuel ratio is equal to or richer than the theoretical air-fuel ratio, comprising: a burner, disposed near the exhaust purifying catalytic device, for heating the exhaust purifying catalytic device; adsorption amount estimating means for estimating an adsorption amount of purifying capability reducing substances, which decreases nitrogen oxide adsorbing ability of the exhaust purifying catalytic device, adsorbed by the exhaust purifying catalytic device, and for determining whether the estimated adsorption amount has reached a predetermined adsorption amount; and catalyst heating means for removing the purifying capability reducing substances from the exhaust purifying catalytic device by activating said burner when said adsorption amount estimating means judges that the adsorption amount of the purifying capability reducing substances has reached the predetermined adsorption amount.

Claim 42

Dependent Claim 213 words

A control apparatus for an internal combustion engine having an exhaust purifying catalytic device disposed in an exhaust passage for reducing emission of nitrogen oxides to atmosphere, the exhaust purifying catalytic device being operable to adsorb nitrogen oxides contained in exhaust gas discharged from the internal combustion engine when the engine is in a lean-combustion mode where an air-fuel ratio of an air-fuel mixture supplied to the engine is leaner than a theoretical air-fuel ratio, and to deoxidize adsorbed nitrogen oxides when the internal combustion engine is in a rich-combustion mode where the air-fuel ratio is equal to or richer than the theoretical air-fuel ratio, comprising: a burner, disposed near the exhaust purifying catalytic device, for heating the exhaust purifying catalytic device; adsorption amount estimating means for estimating an adsorption amount of purifying capability reducing substances, which decreases nitrogen oxide adsorbing ability of the exhaust purifying catalytic device, adsorbed by the exhaust purifying catalytic device, and for determining whether the estimated adsorption amount has reached a predetermined adsorption amount; and catalyst heating means for removing the purifying capability reducing substances from the exhaust purifying catalytic device by activating said burner when said adsorption amount estimating means judges that the adsorption amount of the purifying capability reducing substances has reached the predetermined adsorption amount.

Claim 43

Dependent Claim 218 words

An internal combustion engine control method for reducing emission of nitrogen oxides to atmosphere, by causing nitrogen oxides, contained in exhaust gas discharged from the internal combustion engine, to be adsorbed by an exhaust purifying catalytic device, disposed in an exhaust passage of the internal combustion engine, when the engine is in a lean-combustion mode where an air-fuel ratio of an air-fuel mixture supplied to the engine is leaner than a theoretical air-fuel ratio, and by deoxidizing adsorbed nitrogen oxides by means of the exhaust purifying catalytic device when the internal combustion engine is in a rich-combustion mode where the air-fuel ratio is equal to or richer than the theoretical air-fuel ratio, comprising the steps of: (a) estimating an adsorption amount of purifying capability reducing substances, which decreases nitrogen oxide adsorbing ability of the exhaust purifying catalytic device, adsorbed by the exhaust purifying catalytic device, and determining whether the estimated adsorption amount has reached a predetermined adsorption amount; and (b) removing the purifying capability reducing substances from the exhaust purifying catalytic device by increasing a temperature of the exhaust purifying catalytic device by changing an operating condition of the internal combustion engine so that an exhaust gas temperature increases when it is judged in said step (a) that the estimated adsorption amount has reached the predetermined adsorption amount.

Claim 44

Dependent Claim 218 words

An internal combustion engine control method for reducing emission of nitrogen oxides to atmosphere, by causing nitrogen oxides, contained in exhaust gas discharged from the internal combustion engine, to be adsorbed by an exhaust purifying catalytic device, disposed in an exhaust passage of the internal combustion engine, when the engine is in a lean-combustion mode where an air-fuel ratio of an air-fuel mixture supplied to the engine is leaner than a theoretical air-fuel ratio, and by deoxidizing adsorbed nitrogen oxides by means of the exhaust purifying catalytic device when the internal combustion engine is in a rich-combustion mode where the air-fuel ratio is equal to or richer than the theoretical air-fuel ratio, comprising the steps of: (a) estimating an adsorption amount of purifying capability reducing substances, which decreases nitrogen oxide adsorbing ability of the exhaust purifying catalytic device, adsorbed by the exhaust purifying catalytic device, and determining whether the estimated adsorption amount has reached a predetermined adsorption amount; and (b) removing the purifying capability reducing substances from the exhaust purifying catalytic device by increasing a temperature of the exhaust purifying catalytic device by changing an operating condition of the internal combustion engine so that an exhaust gas temperature increases when it is judged in said step (a) that the estimated adsorption amount has reached the predetermined adsorption amount.

Claim 45

Dependent Claim 55 words

An internal combustion engine control method according to claim 41, wherein said step (a) includes the sub-steps of: (a1) accumulating fuel consumption of the internal combustion engine; and (a2) judging that the estimated adsorption amount has reached the predetermined adsorption amount when the accumulated fuel consumption calculated in said sub-step (a1) reaches a predetermined value.

Claim 46

Dependent Claim 49 words

An internal combustion engine control method according to claim 42, wherein said sub-step (a1) includes accumulating a pulse width of a driving current supplied to a fuel injection valve installed on the internal combustion engine, and calculating said accumulated fuel consumption on the basis of the accumulated pulse width.

Claim 47

Dependent Claim 31 words

An internal combustion engine control method according to claim 42, wherein said sub-step (a1) includes accumulating the fuel consumption only when the internal combustion engine is operated in the lean-combustion mode.

Claim 48

Dependent Claim 52 words

An internal combustion engine control method according to claim 42, further including the sub-step of: (a3) detecting the temperature of the exhaust purifying catalytic device; wherein said sub-step (a1) includes accumulating the fuel consumption only when the catalytic device temperature detected in said sub-step (a3) is not higher than a predetermined temperature.

Claim 49

Dependent Claim 70 words

An internal combustion engine control method according to claim 41, wherein said step (a) includes the sub-steps of: (a1) determining an accumulated value of a travel distance of a vehicle on which the internal combustion engine is mounted; and (a2) judging that the estimated adsorption amount has reached the predetermined adsorption amount when the accumulated value of the vehicle travel distance determined in said sub-step (a1) reaches a predetermined value.

Claim 50

Dependent Claim 71 words

An internal combustion engine control method according to claim 41, wherein said step (a) includes the sub-steps of: (a1) determining an accumulated value of an intake air amount by detecting the intake air amount of the internal combustion engine; and (a2) judging that the estimated adsorption amount has reached the predetermined adsorption amount when the accumulated value of the intake air amount determined in said sub-step (a1) reaches a predetermined value.

Claim 51

Dependent Claim 62 words

An internal combustion engine control method according to claim 41, wherein said step (b) includes burning fuel in the vicinity of the exhaust purifying catalytic device by changing the operating condition of the internal combustion engine so that fuel and air are supplied into the exhaust gas, by which the exhaust gas temperature is increased to heat the exhaust purifying catalytic device.

Claim 52

Dependent Claim 85 words

An internal combustion engine control method according to claim 48, wherein said step (b) includes controlling the air-fuel ratio in part of cylinders of the internal combustion engine to a value lower than the theoretical air-fuel ratio and controlling the air-fuel ratio in the remaining cylinders to a value higher than the theoretical air-fuel ratio, by which rich-combustion operation is performed in said part of cylinders and lean-combustion operation is performed in said remaining cylinders to supply the fuel and air into the exhaust gas.

Claim 53

Dependent Claim 44 words

An internal combustion engine control method according to claim 49, wherein said step (b) includes making an average air-fuel ratio of all the cylinders of the internal combustion engine substantially equal to the theoretical air-fuel ratio when the exhaust purifying catalytic device is heated.

Claim 54

Dependent Claim 62 words

An internal combustion engine control method according to claim 49, wherein said step (b) includes the sub-steps of: (b1) detecting the temperature of the exhaust purifying catalytic device; and (b2) controlling the air-fuel ratio so that the catalytic device temperature is kept at a predetermined temperature after the catalytic device temperature detected in said sub-step (b1) has increased to said predetermined temperature.

Claim 55

Dependent Claim 68 words

An internal combustion engine control method according to claim 51, wherein said sub-step (b2) includes making the average air-fuel ratio of all the cylinders of the internal combustion engine substantially equal to the theoretical air-fuel ratio before the catalytic device temperature detected in said sub-step (b1) and correcting the average air-fuel ratio to a side richer than the theoretical air-fuel ratio after the predetermined temperature has been reached.

Claim 56

Dependent Claim 92 words

An internal combustion engine control method according to claim 49, wherein said step (b) includes controlling the air-fuel ratio for cylinders on one bank side of a V-type engine to a value lower than the theoretical air-fuel ratio and controlling the air-fuel ratio for cylinders on the other bank side of said V-type engine to a value higher than the theoretical air-fuel ratio, by which the rich-combustion operation is performed in the cylinders on said one bank side and the lean-combustion operation is performed in the cylinders on said other band side.

Claim 57

Dependent Claim 47 words

An internal combustion engine control method according to claim 49, further including the step of: (c) retarding ignition timing of said part of cylinders in which the rich-combustion operation is performed and advancing the ignition timing of said remaining cylinders in which the lean-combustion operation is performed.

Claim 58

Dependent Claim 52 words

An internal combustion engine control method according to claim 49, further including the step of: (c) increasing an intake air amount of the internal combustion engine when the rich-combustion operation is performed in said part of cylinders of the internal combustion engine and the lean-combustion operation is performed in the remaining cylinders.

Claim 59

Dependent Claim 77 words

An internal combustion engine control method according to claim 41, further including the step of: (c) disconnecting an automatic transmission from the internal combustion engine by means of a lockup clutch during the time when the temperature of the exhaust purifying catalytic device is raised in said step (b), the lockup clutch being operable to change over a connecting condition between the internal combustion engine and the automatic transmission between a connected state and a disconnected state.

Claim 60

Dependent Claim 59 words

An internal combustion engine control method according to claim 41, wherein said step (b) includes the sub-steps of: (b1) detecting an operating condition of the internal combustion engine; and (b2) heating the exhaust purifying catalytic device when it is judged that the internal combustion engine is in a predetermined medium or heavy load operating condition in said sub-step (b1).

Claim 61

Dependent Claim 58 words

An internal combustion engine control method according to claim 57, wherein said sub-step (b1) includes the sub-steps of: (b11) estimating an exhaust temperature of the internal combustion engine; and (b12) judging that the internal combustion engine is in said predetermined medium or heavy load operating condition when the estimated exhaust temperature is not lower than a predetermined temperature.

Claim 62

Dependent Claim 65 words

An internal combustion engine control method according to claim 58, wherein said sub-step (b11) includes the sub-steps of: (b111) detecting a load of the internal combustion engine; (b112) detecting a rotational speed of the internal combustion engine; and (b113) estimating said exhaust temperature on the basis of the engine load detected in said sub-step (b111) and the engine rotational speed detected in said sub-step (b112).

Claim 63

Dependent Claim 69 words

An internal combustion engine control method according to claim 57, further including the sub-step of: (b3) accumulatively measuring a time period elapsed during the time when it is judged that the internal combustion engine is in said predetermined medium or heavy load operating condition; wherein said step (b2) includes heating the exhaust purifying catalytic device until the elapsed time period measured in said step (b3) reaches a predetermined time.

Claim 64

Dependent Claim 53 words

An internal combustion engine control method according to claim 60, further including the sub-step of: (b4) detecting the temperature of the exhaust purifying catalytic device; wherein said sub-step (b3) includes accumulatively measuring said elapsed time period when the catalytic device temperature detected in said sub-step (b4) is not lower than a predetermined temperature.

Claim 65

Dependent Claim 56 words

An internal combustion engine control method according to claim 60, wherein said sub-step (b3) includes starting to accumulatively measure the elapsed time period from a moment when a predetermined delay time has elapsed after it is judged that the internal combustion engine is in said predetermined medium or heavy load operating condition in said sub-step (b1).

Claim 66

Dependent Claim 76 words

An internal combustion engine control method according to claim 41, further including the steps of: (c) storing the estimated adsorption amount of the purifying capability reducing substances; (d) heating the exhaust purifying catalytic device independently of the estimated adsorption amount when the storage of estimated adsorption amount of the purifying capability reducing substances becomes possible again after the storage of estimated adsorption amount of the purifying capability reducing substances has become impossible in said step (c).

Claim 67

Dependent Claim 30 words

An internal combustion engine control method according to claim 41, wherein said step (b) includes increasing the exhaust gas temperature by changing a burning state of the internal combustion engine.

Claim 68

Dependent Claim 33 words

An internal combustion engine control method according to claim 64, wherein said step (b) includes changing the burning state of the internal combustion engine by retarding ignition timing of the internal combustion engine.

Claim 69

Dependent Claim 39 words

An internal combustion engine control method according to claim 65, further including the step of: (c) increasing an intake air amount during the time when the ignition timing of the internal combustion engine is retarded in said step (b).

Claim 70

Dependent Claim 71 words

An internal combustion engine control method according to claim 65, further including the steps of: (c) detecting a rotational speed of the internal combustion engine; and (d) detecting a volumetric efficiency of the internal combustion engine; wherein said step (b) includes setting a retard amount of the ignition timing on the basis of the engine rotational speed detected in said step (c) and the volumetric efficiency detected in said step (d).

Claim 71

Dependent Claim 83 words

An internal combustion engine control method according to claim 41, further including the steps of: (c) detecting the temperature of the exhaust purifying catalytic device; and (d) controlling the internal combustion engine so that the internal combustion engine is operated in a rich-combustion mode in which the air-fuel ratio of the air-fuel mixture supplied to the internal combustion engine is equal to or richer than the theoretical air-fuel ratio, when the catalytic device temperature detected in said step (c) reaches a predetermined temperature.

Claim 72

Dependent Claim 124 words

An internal combustion engine control method according to claim 41, wherein said step (b) includes the sub-steps of: (b1) controlling the internal combustion engine so that the internal combustion engine is operated in a rich-combustion mode in which the air-fuel ratio of the air-fuel mixture supplied to the internal combustion engine is equal to or richer than the theoretical air-fuel ratio, when it is judged that the estimated adsorption amount has reached the predetermined adsorption amount in said step (a); and (b2) supplying secondary air to an upstream side with respect to the exhaust purifying catalytic device in the exhaust passage when the internal combustion engine is controlled in said sub-step (b1) so that the internal combustion engine is operated in the rich-combustion mode.

Claim 73

Dependent Claim 55 words

An internal combustion engine control method according to claim 69, wherein said step (b) includes the sub-step of: (b3) detecting the temperature of the exhaust purifying catalytic device; wherein said sub-step (b2) includes decreasing a supply amount of the secondary air when the catalytic device temperature detected in said sub-step (b3) reaches a predetermined temperature.

Claim 74

Dependent Claim 80 words

An internal combustion engine control method according to claim 69, further including the steps of: (c) detecting a rotational speed of the internal combustion engine; and (d) detecting a volumetric efficiency of the internal combustion engine; wherein said sub-step (b1) includes setting the air-fuel ratio during the time the internal combustion engine is operated in the rich-combustion mode on the basis of the engine rotational speed detected in said step (c) and the volumetric efficiency detected in said step (d).

Claim 75

Dependent Claim 71 words

An internal combustion engine control method according to claim 69, further including the steps of: (c) detecting a rotational speed of the internal combustion engine; and (d) detecting a volumetric efficiency of the internal combustion engine; wherein said step (b2) includes setting a supply amount of the secondary air on the basis of the engine rotational speed detected in said step (c) and the volumetric efficiency detected in said step (d).

Claim 76

Dependent Claim 35 words

An internal combustion engine control method according to claim 41, wherein said step (b) includes increasing the exhaust gas temperature by changing a flow velocity of the exhaust gas discharged from the internal combustion engine.

Claim 77

Dependent Claim 44 words

An internal combustion engine control method according to claim 73, wherein said step (b) includes changing the flow velocity of the exhaust gas by decreasing a passage area on a downstream side with respect to the exhaust purifying catalytic device in the exhaust passage.

Claim 78

Dependent Claim 58 words

An internal combustion engine control method according to claim 73, further including the steps of: (c) detecting the temperature of the exhaust purifying catalytic device; and (d) supplying fuel to an upstream side with respect to the exhaust purifying catalytic device in the exhaust passage when the catalyst temperature detected in said step (c) reaches a predetermined temperature.

Claim 79

Dependent Claim 86 words

An internal combustion engine control method according to claim 41, wherein said step (b) includes making an exhaust passage length from an exhaust port of the internal combustion engine to the exhaust purifying catalytic device shorter than that before it is judged that the predetermined adsorption amount has been reached when it is judged that the estimated adsorption amount has reached the predetermined adsorption amount in said step (a), by which the temperature of the exhaust gas supplied to the exhaust purifying catalytic device is increased.

Claim 80

Dependent Claim 58 words

An internal combustion engine control method according to claim 76, further including the steps of: (c) detecting the temperature of the exhaust purifying catalytic device; and (d) supplying fuel to an upstream side with respect to the exhaust purifying catalytic device in the exhaust passage when the catalyst temperature detected in said step (c) reaches a predetermined temperature.

Annuity Stage	Window Opens	Payment Deadline	Surcharge Period Until	Estimated Fee	Status
3.5 Years (Year 4)	2000-08-18	2001-02-17	2001-08-19	$2000.00	Window Closed / Lapsed
7.5 Years (Year 8)	2004-08-18	2005-02-17	2005-08-19	$3760.00	Window Closed / Lapsed
11.5 Years (Year 12)	2008-08-18	2009-02-17	2009-08-19	$7700.00	Window Closed / Lapsed

Apparatus and method for internal combustion engine control

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