JP7371599B2 - engine equipment - Google Patents

Description

The present invention relates to an engine device.

Conventionally, this type of engine device has been proposed that includes an engine, a catalyst attached to the exhaust pipe of the engine, and an air-fuel ratio sensor attached to the exhaust pipe downstream of the catalyst ( For example, see Patent Document 1). In this engine device, when there is a request for engine fuel cut, if the air-fuel ratio counter that counts up when the air-fuel ratio detected by the air-fuel ratio sensor is lean reaches a threshold value or more, the engine fuel cut is performed. Release the request.

Japanese Patent Application Publication No. 2018-115600

In the above-mentioned engine device, when the air-fuel ratio sensor is in an inactive state, the air-fuel ratio cannot be detected by the air-fuel ratio sensor, so it is impossible to determine whether the engine is rich or lean. Therefore, if the air-fuel ratio sensor becomes inactive after an engine fuel cut request has started, the air-fuel ratio counter will not be updated appropriately even if the actual air-fuel ratio continues to be lean. There is a possibility that the engine fuel cut request cannot be canceled without

The main object of the engine device of the present invention is to make it possible to cancel an engine fuel cut request even when the air-fuel ratio sensor is in an inactive state.

The engine device of the present invention employs the following means to achieve the above-mentioned main purpose.

The engine device of the present invention includes:
engine and
a catalyst attached to the exhaust pipe of the engine;
an air-fuel ratio sensor attached to the exhaust pipe downstream of the catalyst;
a control device that controls the engine;
An engine device comprising:
The control device is configured such that, when there is a request for fuel cut of the engine, a first integrated air amount as an integrated value of the intake air amount when the air-fuel ratio detected by the air-fuel ratio sensor is lean is equal to or greater than a first threshold value. or when a second integrated air amount as an integrated value of the intake air amount when executing the fuel cut of the engine is equal to or greater than a second threshold, canceling the request for the fuel cut of the engine;
The gist is that.

In the engine device of the present invention, when there is a request for fuel cut of the engine, the first integrated air amount, which is the integrated value of the intake air amount when the air-fuel ratio detected by the air-fuel ratio sensor is lean, is set to the first threshold value. In the above case, or when the second integrated air amount as the integrated value of the intake air amount when executing the engine fuel cut is equal to or larger than the second threshold value, the request for the engine fuel cut is canceled. Thereby, when the air-fuel ratio sensor is in the active state, the request for fuel cut of the engine can be canceled based on the first integrated air amount. Further, when the air-fuel ratio sensor is in an inactive state, that is, when the air-fuel ratio cannot be detected by the air-fuel ratio sensor, the request for fuel cut of the engine can be canceled based on the second integrated air amount.

In the engine device of the present invention, the control device may set the first threshold value and/or the second threshold value based on the temperature of the catalyst. In this case, the control device may set the first threshold value and/or the second threshold value such that the higher the temperature of the catalyst, the larger the second threshold value. By doing so, the fuel cut request can be canceled in consideration of the degree of activation of the air-fuel ratio sensor.

In the engine device of the present invention, the control device may perform the following operations when the temperature of the catalyst is less than a first predetermined temperature and/or when the temperature of the catalyst is higher than a second predetermined temperature higher than the first predetermined temperature. The first threshold value and/or the second threshold value may be set to a value of 0. In this way, when the temperature of the catalyst is low, unnecessary fuel cut can be suppressed. Further, when the temperature of the catalyst is high, the fuel cut can prevent the high temperature catalyst from being exposed to a large amount of oxygen and promoting deterioration of the catalyst.

1 is a configuration diagram schematically showing the configuration of a hybrid vehicle 20 equipped with an engine device. 2 is a configuration diagram showing an outline of the configuration of an engine 22. FIG. 2 is a flowchart showing an example of a processing routine executed by the engine ECU 24. FIG. FIG. 3 is an explanatory diagram showing an example of a first threshold value setting map. 2 is a flowchart showing an example of a processing routine executed by the engine ECU 24. FIG.

Next, a mode for carrying out the present invention will be described using examples.

FIG. 1 is a block diagram schematically showing the structure of a hybrid vehicle 20 equipped with an engine device according to an embodiment of the present invention. As illustrated, the hybrid vehicle 20 of the embodiment includes an engine 22, an engine electronic control unit (hereinafter referred to as "engine ECU") 24, a planetary gear 30, motors MG1 and MG2, and inverters 41 and 42. It includes a motor electronic control unit (hereinafter referred to as "motor ECU") 40, a battery 50, and a hybrid electronic control unit (hereinafter referred to as "HVECU") 70. The "engine device" in the embodiment mainly corresponds to the engine 22 and the engine ECU 24.

The engine 22 is configured as an internal combustion engine that outputs power using gasoline, light oil, or the like as fuel, and is connected to the carrier of the planetary gear 30. FIG. 2 is a configuration diagram showing an outline of the configuration of the engine 22. As shown in FIG. As shown in the figure, the engine 22 sucks air purified by an air cleaner 122 into an intake pipe 123, passes it through a throttle valve 124, and injects fuel from a fuel injection valve 126 to mix the air and fuel. The air-fuel mixture is drawn into the combustion chamber 129 via the intake valve 128. Then, the inhaled air-fuel mixture is explosively combusted by electric sparks from the ignition plug 130, and the reciprocating motion of the piston 132 pushed down by the energy is converted into rotational motion of the crankshaft 26. Exhaust gas discharged from the combustion chamber 129 to the exhaust pipe 133 via the exhaust valve 131 is discharged to the outside air via purifiers 134 and 136. The purification devices 134 and 136 have catalysts (three-way catalysts) 134a and 136a that purify harmful components such as carbon monoxide (CO), hydrocarbons (HC), and nitrogen oxides (NOx) in exhaust gas.

Although not shown, the engine ECU 24 is configured as a microprocessor centered on a CPU, and in addition to the CPU, includes a ROM for storing processing programs, a RAM for temporarily storing data, input/output ports, and communication ports. Be prepared. Signals from various sensors necessary to control the operation of the engine 22 are input to the engine ECU 24 via an input port. Signals input to the engine ECU 24 include, for example, the crank angle θcr from the crank position sensor 140 that detects the rotational position of the crankshaft 26 of the engine 22, and the water temperature sensor 142 that detects the temperature of the cooling water of the engine 22. One example is the cooling water temperature Tw. The cam angles θci and θco from the cam position sensor 144 that detects the rotational position of the intake camshaft that opens and closes the intake valve 128 and the rotational position of the exhaust camshaft that opens and closes the exhaust valve 131 can also be cited. The throttle opening TH from the throttle position sensor 124a that detects the position of the throttle valve 124, the intake air amount Qa from the air flow meter 148 attached to the intake pipe 123, and the intake air amount Qa from the temperature sensor 149 attached to the intake pipe 123. Temperature Ta can also be mentioned. The air-fuel ratio AF1 from the air-fuel ratio sensor 135a installed upstream of the purification device 134 in the exhaust pipe 133, and the air-fuel ratio sensor 135b installed between the purification device 134 and the purification device 136 in the exhaust pipe 133. The air-fuel ratio AF2 can also be mentioned.

The engine ECU 24 outputs various control signals for controlling the operation of the engine 22 via an output port. Signals output from the engine ECU 24 include a control signal to the throttle motor 124b that adjusts the position of the throttle valve 124, a control signal to the fuel injection valve 126, and a control signal to the spark plug 130. Engine ECU 24 is connected to HVECU 70 via a communication port.

The engine ECU 24 calculates the rotation speed Ne of the engine 22 based on the crank angle θcr from the crank position sensor 140. The engine ECU 24 also calculates the load factor (ratio of the volume of air actually taken in in one cycle to the stroke volume per cycle of the engine 22) KL, etc. based on the intake air amount Qa and the rotation speed Ne of the engine 22. is being calculated. Furthermore, the engine ECU 24 estimates the temperatures Tc1 and Tc2 of the catalysts 134a and 136a of the purifiers 134 and 136 based on the cooling water temperature Tw from the water temperature sensor 142, the rotational speed Ne of the engine 22, and the load factor KL. .

The planetary gear 30 is configured as a single pinion type planetary gear mechanism. The sun gear of the planetary gear 30 is connected to the rotor of the motor MG1. A drive shaft 36 connected to drive wheels 39a and 39b via a differential gear 38 is connected to the ring gear of the planetary gear 30. A crankshaft 26 of the engine 22 is connected to the carrier of the planetary gear 30.

The motor MG1 is configured, for example, as a synchronous generator motor, and has a rotor connected to the sun gear of the planetary gear 30, as described above. The motor MG2 is configured as, for example, a synchronous generator motor, and has a rotor connected to the drive shaft 36. Inverters 41 and 42 are used to drive motors MG1 and MG2, and are connected to battery 50 via power line 54. A smoothing capacitor 57 is attached to the power line 54. The motors MG1 and MG2 are rotationally driven by the motor ECU 40 controlling the switching of a plurality of switching elements (not shown) of the inverters 41 and 42. The battery 50 is configured as, for example, a lithium ion secondary battery or a nickel hydride secondary battery, and is connected to a power line 54.

Although not shown, the motor ECU 40 is configured as a microprocessor centered on a CPU, and in addition to the CPU, it also includes a ROM for storing processing programs, a RAM for temporarily storing data, an input/output port, and a communication port. Be prepared. The motor ECU 40 receives signals from various sensors necessary to drive and control the motors MG1 and MG2, such as rotational position θm1 from rotational position detection sensors 43 and 44 that detect the rotational positions of the rotors of the motors MG1 and MG2. , θm2, etc. are input through the input port. Motor ECU 40 outputs switching control signals to a plurality of switching elements of inverters 41 and 42 through output ports. Motor ECU 40 is connected to HVECU 70 via a communication port. The motor ECU 40 determines the electrical angles θe1, θe2, angular velocities ωm1, ωm2, and rotational speeds Nm1, Nm2 of the motors MG1, MG2 based on the rotational positions θm1, θm2 of the rotors of the motors MG1, MG2 from the rotational position detection sensors 43, 44. is being calculated.

Although not shown, the HVECU 70 is configured as a microprocessor centered on a CPU, and includes, in addition to the CPU, a ROM for storing processing programs, a RAM for temporarily storing data, an input/output port, and a communication port. . Signals from various sensors are input to the HVECU 70 via input ports. Examples of signals input to the HVECU 70 include an ignition signal from an ignition switch 80 and a shift position SP from a shift position sensor 82 that detects the operating position of the shift lever 81. Further, the accelerator opening degree Acc from the accelerator pedal position sensor 84 which detects the amount of depression of the accelerator pedal 83, the brake pedal position BP from the brake pedal position sensor 86 which detects the amount of depression of the brake pedal 85, and the brake pedal position BP from the vehicle speed sensor 88. Vehicle speed V can also be mentioned. As described above, the HVECU 70 is connected to the engine ECU 24, motor ECU 40, and battery ECU 52 via the communication port.

The hybrid vehicle 20 according to the embodiment configured in this manner can operate in a hybrid driving mode (HV driving mode) in which the vehicle travels while the engine 22 rotates, or an electric driving mode (EV driving mode) in which the vehicle travels while the engine 22 stops rotating. The vehicle runs while switching (while operating the engine 22 intermittently).

Next, the operation of the hybrid vehicle 20 equipped with the engine device of the embodiment configured as described above, particularly the operation when canceling the fuel cut request of the engine 22, will be described. Here, the fuel cut request for the engine 22 is made, for example, when the air-fuel ratio sensor 135b is in an active state (can detect the air-fuel ratio AF2) and the air-fuel ratio AF2 detected by the air-fuel ratio sensor 135b has been maintained for a predetermined period of time. Started when rich and continuous. In the embodiment, the air-fuel ratio sensor 135b can detect the air-fuel ratio AF2 when in the activated state (when the temperature is higher than the activation temperature), and when it is in the inactive state (when the temperature is lower than the activation temperature). It is assumed that the fuel ratio AF2 cannot be detected. In addition, when a request for fuel cut in engine 22 is made, when the execution conditions for fuel cut in engine 22 are satisfied, for example, when the accelerator is turned off in the HV driving mode, the engine 22 Carry out fuel cuts. FIG. 3 is a flowchart showing an example of a processing routine executed by the engine ECU 24. As shown in FIG. This processing routine starts to be executed when a request for fuel cut of the engine 22 is started.

When the processing routine of FIG. 3 is executed, the engine ECU 24 first sets the activation state flag Faf, the air-fuel ratio AF2 (when the air-fuel ratio sensor 135b is in the active state), the intake air amount Qa, and the temperatures of the catalysts 134a and 136a. Data such as Tc1 and Tc2 are input (step S100). Here, a value set by an active state flag setting routine (not shown) is input to the active state flag Faf. In the active state flag setting routine, the engine ECU 24 sets the active state flag Faf to a value of 1 when the air-fuel ratio sensor 135b is in the active state (when the air-fuel ratio AF2 can be detected), and when the air-fuel ratio sensor 135b is in the active state. When in the inactive state (when the air-fuel ratio AF2 cannot be detected), the active state flag Faf is set to a value of 0. As the air-fuel ratio AF2, a value detected by the air-fuel ratio sensor 135b is input when the air-fuel ratio sensor 135b is in an active state, and is not input when the air-fuel ratio sensor 135b is in an inactive state. A value detected by the air flow meter 148 is input as the intake air amount Qa. As the temperatures Tc1 and Tc2 of the catalysts 134a and 136a, values estimated based on the cooling water temperature Tw of the engine 22, the rotational speed Ne, and the load factor KL are input.

After inputting the data in this way, the value of the active state flag Faf is checked (step S105). When the active state flag Faf is 1, that is, when the air-fuel ratio sensor 135b is in the active state, it is determined whether the air-fuel ratio AF2 is lean (step S110), and when the air-fuel ratio AF2 is not lean, Return to step S110. At this time, the fuel cut request for the engine 22 continues.

When the air-fuel ratio AF2 is lean in step S110, an integrated air amount Gle as an integrated value of the intake air amount Qa when the air-fuel ratio AF2 is lean is calculated based on the intake air amount Qa (step S120). This process is performed by setting a new cumulative air amount Gle to a value obtained by adding the intake air amount Qa to the current cumulative air amount Gle. Note that the integrated air amount Gle is reset to the value 0 as an initial value when a request for fuel cut of the engine 22 is started.

Subsequently, a threshold value Gleref is set based on the temperatures Tc1 and Tc2 of the catalysts 134a and 136a (step S130). Here, the threshold value Gleref is a threshold value for determining whether to cancel the fuel cut request based on the integrated air amount Gle, and the temperature Tc1, Tc2 of the catalysts 134a, 136a and the first threshold value setting map. Set based on. The first threshold value setting map is predetermined as a relationship between the temperatures Tc1 and Tc2 of the catalysts 134a and 136a and the threshold value Gleref, and is stored in a ROM (not shown). FIG. 4 is an explanatory diagram showing an example of a first threshold value setting map. As shown in the figure, the threshold value Gleref is set in a region where the temperature Tc1 of the catalyst 134a is lower than the predetermined temperature T11 and a temperature Tc2 of the catalyst 136a is lower than the predetermined temperature T21, a region where the temperature Tc1 of the catalyst 134a is higher than the predetermined temperature T12, and a region where the temperature Tc1 of the catalyst 134a is higher than the predetermined temperature T12, In a region where the temperature Tc2 is higher than the predetermined temperature T22, a value of 0 is set. Further, in other regions, the threshold value Gleref is set within a positive range so that the higher the temperature Tc1 of the catalyst 134a is, the higher the threshold value Gleref is, and the higher the temperature Tc2 of the catalyst 136a is, the higher the threshold Gleref is. Here, for the threshold values T11 and T21, for example, the activation temperatures of the catalysts 134a and 136a are used, respectively. The threshold values T12 and T22 are, for example, the lower limit of a temperature range in which deterioration of the catalysts 134a and 136a may be accelerated when the catalysts 134a and 136a are exposed to a large amount of oxygen due to a fuel cut in the engine 22. used.

After setting the threshold value Gleref in this way, the integrated air amount Gle is compared with the threshold value Gleref (step S140). Then, when the cumulative air amount Gle is less than the threshold value Gleref, it is determined that there is no need to cancel the fuel cut request for the engine 22, and the process returns to step S100. At this time, the fuel cut request for the engine 22 continues. On the other hand, when the cumulative air amount Gle is equal to or greater than the threshold value Gleref, the fuel cut request is canceled (step S190), and this routine ends. Thereby, when the air-fuel ratio sensor 135b is in the active state, the request for fuel cut of the engine 22 can be canceled based on the integrated air amount Gle when the air-fuel ratio AF2 is lean.

In the embodiment, the temperature Tc1 of the catalyst 134a is less than the predetermined temperature T11 and the temperature Tc2 of the catalyst 136a is less than the predetermined temperature T21, the temperature Tc1 of the catalyst 134a is greater than or equal to the predetermined temperature T12, and the temperature Tc2 of the catalyst 136a is In a region where the temperature is higher than the predetermined temperature T22, the fuel cut request is immediately canceled by setting the threshold value Gleref to 0. Thereby, when the catalysts 134a, 136a are in an inactive state, unnecessary fuel cut can be suppressed, and when the catalysts 134a, 136a are at a high temperature, the fuel cut can be performed to prevent the catalysts 134a, 136a from being cut. It is possible to prevent catalysts 134a and 136a from being exposed to a large amount of oxygen and deterioration of the catalysts 134a and 136a being accelerated.

When the activation state flag Faf has a value of 0 in step S105, that is, when the air-fuel ratio sensor 135b is in an inactive state, it is determined whether a fuel cut of the engine 22 is being executed (step S150). Then, when the fuel cut of the engine 22 is not being executed, the process returns to step S100. At this time, the fuel cut request for the engine 22 continues.

When the fuel cut of the engine 22 is being executed in step S150, the cumulative air amount Gfc as the cumulative value of the intake air amount Qa while the fuel cut of the engine 22 is being performed is calculated based on the intake air amount Qa (step S150). S160). This process is performed by setting a value obtained by adding the intake air amount Qa to the current cumulative air amount Gfc as a new cumulative air amount Gfc. Note that the cumulative air amount Gfc is reset to the value 0 as an initial value when a request for fuel cut of the engine 22 is started.

Subsequently, a threshold value Gfcref is set based on the temperatures Tc1 and Tc2 of the catalysts 134a and 136a (step S170). Here, the threshold value Gfcref is a threshold value for determining whether or not to cancel the fuel cut request based on the cumulative air amount Gfc, and is based on the temperatures Tc1 and Tc2 of the catalysts 134a and 136a and the first threshold value setting described above. The second threshold setting map is set based on the second threshold setting map, which is similar to the second threshold setting map. In the embodiment, the threshold value Gfcref is set to have the same tendency as the threshold value Gleref. Specifically, the threshold value Gfcref is set in a region where the temperature Tc1 of the catalyst 134a is less than the predetermined temperature T11 and a temperature Tc2 of the catalyst 136a is less than the predetermined temperature T21, a region where the temperature Tc1 of the catalyst 134a is equal to or higher than the predetermined temperature T12, or a region where the temperature Tc1 of the catalyst 134a is less than the predetermined temperature T12, In a region where the temperature Tc2 is higher than the predetermined temperature T22, a value of 0 is set. Further, in other regions, the threshold value Gleref is set within a positive range so that the higher the temperature Tc1 of the catalyst 134a is, the higher the threshold value Gleref is, and the higher the temperature Tc2 of the catalyst 136a is, the higher the threshold Gleref is.

After setting the threshold value Gfcref in this way, the integrated air amount Gfc is compared with the threshold value Gfcref (step S180). Then, when the cumulative air amount Gfc is less than the threshold value Gfcref, it is determined that there is no need to cancel the fuel cut request for the engine 22, and the process returns to step S100. At this time, the fuel cut request for the engine 22 continues. On the other hand, when the cumulative air amount Gfc is equal to or greater than the threshold value Gleref, the fuel cut request is canceled (step S190), and this routine ends. Thereby, when the air-fuel ratio sensor 135b is in the inactive state, the request for fuel cut of the engine 22 can be canceled based on the cumulative air amount Gfc during which the fuel cut of the engine 22 is being performed. In the embodiment, the fuel cut request for the engine 22 is started when the air-fuel ratio sensor 135b is in the active state and the air-fuel ratio AF2 continues to be rich for a predetermined period of time. Therefore, when the air-fuel ratio sensor 135b subsequently becomes inactive, for example, when the outside temperature is low, a fuel cut request for the engine 22 is started, and then the engine 22 is stopped and the transition to the EV driving mode is made. However, an example is when the EV driving mode continues for a certain period of time.

In the embodiment, the temperature Tc1 of the catalyst 134a is less than the predetermined temperature T11 and the temperature Tc2 of the catalyst 136a is less than the predetermined temperature T21, the temperature Tc1 of the catalyst 134a is greater than or equal to the predetermined temperature T12, and the temperature Tc2 of the catalyst 136a is In a region where the temperature is equal to or higher than the predetermined temperature T22, the fuel cut request is immediately canceled by setting the threshold value Gfcref to a value of 0. Thereby, when the catalysts 134a, 136a are in an inactive state, unnecessary fuel cut can be suppressed, and when the catalysts 134a, 136a are at a high temperature, the fuel cut can be performed to prevent the catalysts 134a, 136a from being cut. It is possible to prevent catalysts 134a and 136a from being exposed to a large amount of oxygen and deterioration of the catalysts 134a and 136a being accelerated.

In the engine device installed in the hybrid vehicle 20 of the embodiment described above, when there is a request for fuel cut of the engine 22, the cumulative air amount Gle when the air-fuel ratio AF2 detected by the air-fuel ratio sensor 135b is lean is When the cumulative air amount Gfc is equal to or greater than the threshold value Gleref, or when the cumulative air amount Gfc while executing the fuel cut of the engine 22 is equal to or greater than the threshold value Gfcref, the request for the fuel cut of the engine 22 is canceled. Thereby, when the air-fuel ratio sensor 135b is in the active state, the fuel cut request for the engine 22 can be canceled based on the integrated air amount Gle. Furthermore, when the air-fuel ratio sensor 135b is inactive, that is, when the air-fuel ratio AF2 cannot be detected by the air-fuel ratio sensor 135b, the request for fuel cut of the engine 22 can be canceled based on the cumulative air amount Gfc.

In the engine device installed in the hybrid vehicle 20 of the embodiment, the threshold value Gleref is such that the temperature Tc1 of the catalyst 134a is equal to or higher than the threshold value T11, the temperature Tc2 of the catalyst 136a is equal to or higher than the threshold value T21, and the temperature Tc1 of the catalyst 134a is equal to or lower than the threshold value T12. In a region where the temperature Tc2 of the catalyst 136a is equal to or lower than the threshold value T22, it is set such that the higher the temperature Tc1 of the catalyst 134a is, the higher the temperature Tc2 of the catalyst 136a is, within a positive range. However, the threshold Gleref may be a constant value in this region. The threshold value Gfcref can be considered in the same way.

In the engine device installed in the hybrid vehicle 20 of the embodiment, the threshold value Gleref is set to a value of 0 in a region where the temperature Tc1 of the catalyst 134a is less than the predetermined temperature T11 and the temperature Tc2 of the catalyst 136a is less than the predetermined temperature T21. I took it as a thing. However, the threshold Gleref may be set to a positive value in this region. The threshold value Gfcref can be considered in the same way.

In the engine device installed in the hybrid vehicle 20 of the embodiment, the threshold value Gleref is set to a value of 0 in a region where the temperature Tc1 of the catalyst 134a is equal to or higher than the predetermined temperature T12, or in a region where the temperature Tc2 of the catalyst 136a is equal to or higher than the predetermined temperature T22. It was assumed that However, the threshold Gleref may be set to a positive value in this region. The threshold value Gfcref can be considered in the same way.

In the engine device installed in the hybrid vehicle 20 of the example, the threshold value Gleref is set based on the temperatures Tc1 and Tc2 of the catalysts 134a and 136a. However, the threshold Gleref may be set based only on one of the temperatures Tc1 and Tc2 of the catalysts 134a and 136a. The threshold value Gfcref can be considered in the same way.

In the engine device installed in the hybrid vehicle 20 of the example, the threshold value Gleref is set based on the temperatures Tc1 and Tc2 of the catalysts 134a and 136a. However, instead of or in addition to the temperatures Tc1 and Tc2 of the catalysts 134a and 136a, the threshold Gleref is determined based on the degree of deterioration Dc1 and Dc2 of the catalysts 134a and 136a, and the maximum oxygen storage amounts OSM1 and OSM2 of the catalysts 134a and 136a. It may be set based on at least one. The threshold value Gfcref can be considered in the same way.

In these cases, for example, the engine ECU 24 may execute the processing routine shown in FIG. 5 instead of the processing routine shown in FIG. 3. The processing routine of FIG. 5 has the following points: the processing of step S100 is replaced with the processing of step S102, the processing of step S130 is replaced with the processing of steps S132 to S136, and the processing of step S170 is replaced with the processing of steps S172 to S176. The processing routine is the same as the processing routine in FIG. 3 except that the processing has been replaced. Therefore, among the processing routines in FIG. 5, the same steps as those in the processing routine in FIG. 3 are given the same step numbers, and detailed description thereof will be omitted.

When the processing routine of FIG. 5 is executed, the engine ECU 24 first sets the activation state flag Faf and the air-fuel ratio AF2 (when the air-fuel ratio sensor 135b is in the active state), similarly to the processing of step S100 of the processing routine of FIG. (step S102). Here, the deterioration degrees Dc1 and Dc2 of the catalysts 134a and 136a are estimated based on the intake air amount Qa, the air-fuel ratios AF1 and AF2, and the temperatures Tc1 and Tc2 of the catalysts 134a and 136a, for example, by a deterioration degree estimation routine (not shown). The value entered will be entered.

When the activation state flag Faf is the value 1 in step S105, that is, the air-fuel ratio sensor 135b is in the active state, and the air-fuel ratio AF2 is lean in step S110, when the integrated air amount Gle is calculated in step S120, A threshold value Gleref is set (steps S132 to S136), and processing from step S140 onwards is executed.

In setting the threshold Gleref, first, temperature coefficients Ktle1 and Ktle2 are set based on the temperatures Tc1 and Tc2 of the catalysts 134a and 136a (step S132). Subsequently, deterioration coefficients Kdle1 and Kdle2 are set based on the degree of deterioration Dc1 and Dc2 of the catalysts 134a and 136a (step S134). Then, a threshold value Gleref is set as the sum of the product of the maximum oxygen storage amount OSM1, the temperature coefficient Ktle1, and the deterioration coefficient Kdle1, and the product of the maximum oxygen storage amount OSM2, the temperature coefficient Ktle2, and the deterioration coefficient Kdle2 (step S136). Here, the temperature coefficients Ktle1 and Ktle2 are obtained by applying the temperatures Tc1 and Tc2 of the catalysts 134a and 136a to a map that predetermines the relationship between the temperatures Tc1 and Tc2 of the catalysts 134a and 136a and the temperature coefficients Ktle1 and Ktle2, for example. It is obtained by The deterioration coefficients Kdle1 and Kdle2 can be determined, for example, by applying the deterioration degrees Dc1 and Dc2 of the catalysts 134a and 136a to a map that predetermines the relationship between the deterioration degrees Dc1 and Dc2 of the catalysts 134a and 136a and the deterioration coefficients Kdle1 and Kdle2. can get. For the maximum oxygen storage amounts OSM1 and OSM2, for example, a predetermined value is used as the maximum value of the oxygen storage amounts OS1 and OS2 of the catalysts 134a and 136a when the catalysts 134a and 136a are not deteriorated.

When the activation state flag Faf is 1 in step S105, that is, the air-fuel ratio sensor 135b is in the active state, and the fuel cut of the engine 22 is being executed in step S150, the cumulative air amount Gfc is determined in step S160. After the calculation, a threshold value Gfcref is set (steps S172 to S176), and the processing from step S180 onwards is executed.

In setting the threshold value Gfcref, first, temperature coefficients Ktfc1 and Ktfc2 are set based on the temperatures Tc1 and Tc2 of the catalysts 134a and 136a (step S172). Subsequently, deterioration coefficients Kdfc1 and Kdfc2 are set based on the deterioration degrees Dc1 and Dc2 of the catalysts 134a and 136a (step S174). Then, a threshold value Gfcref is set as the sum of the product of the maximum oxygen storage amount OSM1, the temperature coefficient Ktfc1, and the deterioration coefficient Kdfc1, and the product of the maximum oxygen storage amount OSM2, the temperature coefficient Ktfc2, and the deterioration coefficient Kdfc2 (step S176). Here, the temperature coefficients Ktfc1 and Ktfc2 are obtained by applying the temperatures Tc1 and Tc2 of the catalysts 134a and 136a to a map that predetermines the relationship between the temperatures Tc1 and Tc2 of the catalysts 134a and 136a and the temperature coefficients Ktfc1 and Ktfc2, for example. It is obtained by The deterioration coefficients Kdfc1 and Kdfc2 can be determined, for example, by applying the deterioration degrees Dc1 and Dc2 of the catalysts 134a and 136a to a map that predetermines the relationship between the deterioration degrees Dc1 and Dc2 of the catalysts 134a and 136a and the deterioration coefficients Kdfc1 and Kdfc2. can get.

By setting the threshold value Gleref and the threshold value Gfcref as described above, the threshold value Gleref and the threshold value Gfcref can be set to more appropriate values, so that the fuel cut request for the engine 22 can be canceled at a more appropriate timing. .

In the engine device installed in the hybrid vehicle 20 of the embodiment, the engine 22 is provided with catalysts 134a and 136a attached to an exhaust pipe 133. However, the engine 22 may include only the catalyst 134a.

The engine device of the example is assumed to be installed in a hybrid vehicle 20. However, it may also be installed in a general automobile that does not have a motor for driving. Further, the present invention may take the form of an engine device mounted on a vehicle other than an automobile, or may take the form of an engine device mounted on non-moving equipment such as construction equipment.

The correspondence between the main elements of the embodiments and the main elements of the invention described in the column of means for solving the problems will be explained. In the embodiment, the engine 22 corresponds to an "engine", the catalysts 134a and 136a correspond to a "catalyst", the air-fuel ratio sensor 37b corresponds to an "air-fuel ratio sensor", and the engine ECU 24 corresponds to a "control device". .
・Is the wavy line part OK?

The correspondence relationship between the main elements of the examples and the main elements of the invention described in the column of means for solving the problem is that the example implements the invention described in the column of means for solving the problem. Since this is an example for specifically explaining a form for solving the problem, it is not intended to limit the elements of the invention described in the column of means for solving the problems. In other words, the interpretation of the invention described in the column of means for solving the problem should be based on the description in that column, and the examples are based on the description of the invention described in the column of means for solving the problem. This is just one specific example.

Although the embodiments of the present invention have been described above using examples, the present invention is not limited to these examples in any way, and may be modified in various forms without departing from the gist of the present invention. Of course, it can be implemented.

INDUSTRIAL APPLICATION This invention can be utilized for the manufacturing industry of an engine device, etc.

20 hybrid vehicle, 22 engine, 24 engine ECU, 26 crankshaft, 30 planetary gear, 36 drive shaft, 38 differential gear, 39a, 39b drive wheels, 40 motor ECU, 41, 42 inverter, 43, 44 rotational position detection sensor, 50 Battery, 54 Power line, 57 Capacitor, 70 HVECU, 80 Ignition switch, 81 Shift lever, 82 Shift position sensor, 83 Accelerator pedal, 84 Accelerator pedal position sensor, 85 Brake pedal, 86 Brake pedal position sensor, 88 Vehicle speed sensor, 89 atmospheric pressure sensor, 122 air cleaner, 124 throttle valve, 124a throttle position sensor, 123 intake pipe, 126 fuel injection valve, 128 intake valve, 129 combustion chamber, 130 spark plug, 131 exhaust valve, 132 piston, 133 exhaust pipe, 134 purification Device, 134a, 136a catalyst, 135a, 135b air-fuel ratio sensor, 140 crank position sensor, 144 cam position sensor, 142 water temperature sensor, 148 air flow meter, MG1, MG2 motor.

Claims (1)

engine and
a catalyst attached to the exhaust pipe of the engine;
an air-fuel ratio sensor attached to the exhaust pipe downstream of the catalyst;
a control device that controls the engine;
An engine device comprising:
When the air-fuel ratio sensor is in an active state when there is a request for fuel cut of the engine, the control device is configured to calculate an integrated value of the intake air amount when the air-fuel ratio detected by the air-fuel ratio sensor is lean. If the first integrated air amount of the engine is equal to or greater than a first threshold, the fuel cut request for the engine is canceled, and if the air-fuel ratio sensor is in an inactive state, the intake air when the engine fuel cut is executed. canceling the fuel cut request for the engine when a second integrated air amount as an integrated value of the air amount is equal to or greater than a second threshold;
engine equipment.

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