Vehicle control device

Abstract

To suppress destabilization of a combustion state and deterioration of fuel economy while securing the required function of a catalyst.SOLUTION: A vehicle 500 has an internal combustion engine 10 including a spark plug 19, a catalyst 22, and a crankshaft 31, and an automatic transmission 50 that is connected to the crankshaft 31 and can change a shift range to a drive range for moving the vehicle 500 forward or a reverse range for moving the vehicle 500 backward. A control device 100 for the vehicle 500 can execute catalyst warming-up processing for accelerating warming-up of the catalyst 22 by setting the ignition timing of the spark plug 19 to the retarded side relative to a compression top dead center. During execution of the catalyst warming-up processing, when the shift range of the automatic transmission 50 is in the reverse range, the control device 100 sets the ignition timing of the spark plug 19 to the advance side and reduce the engine speed, as compared with when the shift range is in the drive range.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present invention relates to a vehicle control device. [Background technology]

[0002] The vehicle disclosed in Patent Document 1 has an internal combustion engine, an automatic transmission, and a control device. The internal combustion engine has spark plugs that ignite the engine in the cylinders, and a catalyst that purifies the exhaust gas. The internal combustion engine also has a crankshaft that rotates as fuel is burned in the cylinders. The automatic transmission is connected to the crankshaft.

[0003] The control device corrects the ignition timing to be retarded when the estimated temperature of the catalyst is less than a threshold immediately after starting the internal combustion engine. This makes it easier for the exhaust gas to reach the catalyst at a high temperature, accelerating the warming up of the catalyst. When correcting the ignition timing to be retarded, the control device changes the amount of retard correction depending on whether the shift range of the automatic transmission is in the driving range or the non-driving range. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] JP 2008-008184 A Summary of the Invention [Problem to be solved by the invention]

[0005] If the ignition timing is retarded to accelerate the warm-up of the catalyst, the combustion state of the air-fuel mixture becomes unstable. Also, if the engine speed is increased to accelerate the warm-up of the catalyst, the fuel consumption increases, and fuel economy deteriorates. When warming up the catalyst, it is necessary to proceed with the warm-up so that the catalyst functions optimally while taking into account these combustion states and fuel economy.

[0006] Here, when the shift range of the automatic transmission is the driving range, the output required of the internal combustion engine differs between when the drive range is selected and when the reverse range is selected, and the amount of exhaust gas differs accordingly. Accordingly, the exhaust gas purification ability of the catalyst required in each case, and further, the warm-up speed required for warming up the catalyst, differs. Therefore, between the drive range and the reverse range, the one that should be prioritized when warming up the catalyst differs among the warm-up speed of the catalyst, the combustion state, and the fuel efficiency. Therefore, when all of these three elements are taken into consideration, there is a risk that the optimal control corresponding to each shift range cannot necessarily be performed by simply changing the control related to the warm-up of the catalyst based on the driving range and the non-driving range as in Patent Document 1. [Means for solving the problem]

[0007] A vehicle control device for solving the above problem is applied to a vehicle having an internal combustion engine equipped with a spark plug for igniting in a cylinder, a catalyst for purifying exhaust, and a crankshaft, and an automatic transmission connected to the crankshaft and capable of switching the shift range to a drive range for moving the vehicle forward or a reverse range for moving the vehicle backward, and is capable of executing a catalyst warm-up process that promotes warm-up of the catalyst by retarding the ignition timing of the spark plug from top dead center of compression, and during execution of the catalyst warm-up process, when the shift range of the automatic transmission is in the reverse range, the ignition timing of the spark plug is advanced and the engine rotation speed is reduced compared to when the shift range is in the drive range.

[0008] When the vehicle is traveling in the reverse range, the output required of the internal combustion engine is smaller than when the vehicle is traveling in the drive range. Also, the amount of exhaust is smaller. Therefore, when the shift range is in the reverse range during the catalyst warm-up process, the exhaust purification ability of the catalyst, i.e., the temperature of the catalyst, does not need to be so high. Therefore, when the shift range is in the reverse range during the catalyst warm-up process, it is permissible to suppress the warm-up speed of the catalyst. Therefore, in the above configuration, when the shift range is in the reverse range, the ignition timing is advanced and the engine speed is lower than when the shift range is in the drive range. This makes it possible to suppress the instability of the combustion state and the deterioration of fuel efficiency while ensuring the necessary catalyst function. [Brief description of the drawings]

[0009] [Figure 1] FIG. 1 is a schematic diagram of a vehicle. [Diagram 2] FIG. 2 is a schematic diagram showing the relationship between the starting temperature and the target engine speed for each shift range. [Diagram 3] FIG. 3 is a schematic diagram showing the relationship between the starting temperature and the target ignition timing for each shift range. [Figure 4] FIG. 4 is a flowchart showing the procedure of the catalyst warm-up process. [Diagram 5] FIG. 5 is a time chart showing an example of a change in catalyst temperature over time accompanying the execution of the catalyst warm-up process. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0010] Hereinafter, an embodiment of a vehicle control device will be described with reference to the drawings. <Vehicle Overview> 1, a vehicle 500 has an internal combustion engine 10. The internal combustion engine 10 is a drive source of the vehicle 500.

[0011] The internal combustion engine 10 has an engine body 10A and a crankshaft 31. The engine body 10A has a plurality of cylinders 11. Each cylinder 11 is a space partitioned in the engine body 10A. Although not shown, each cylinder 11 houses a piston. In each cylinder 11, the piston is capable of reciprocating. The piston is connected to the crankshaft 31 via a connecting rod. The crankshaft 31 rotates in response to the reciprocating motion of the piston.

[0012] The engine body 10A has a water jacket 18. The water jacket 18 is a passage through which cooling water flows. The water jacket 18 is positioned around the multiple cylinders 11.

[0013] The internal combustion engine 10 has a plurality of spark plugs 19. One spark plug 19 is provided for each cylinder 11. The tip of the spark plug 19 is located inside the cylinder 11. The spark plug 19 ignites an air-fuel mixture of intake air and fuel. As a result, the air-fuel mixture is burned inside the cylinder 11.

[0014] The internal combustion engine 10 has an intake passage 15, a throttle valve 16, and multiple fuel injection valves 17. The intake passage 15 is a passage for introducing intake air into each cylinder 11. The intake passage 15 is connected to each cylinder 11. The throttle valve 16 is located midway through the intake passage 15. The throttle valve 16 adjusts the amount of intake air GA flowing into the intake passage 15. The multiple fuel injection valves 17 are located downstream of the throttle valve 16 in the intake passage 15. The fuel injection valve 17 is provided for each cylinder 11. The fuel injection valve 17 injects fuel to supply the fuel into the cylinder 11.

[0015] The internal combustion engine 10 has an exhaust passage 21 and a three-way catalyst (hereinafter simply referred to as the catalyst) 22. The exhaust passage 21 is a passage for discharging exhaust gas from each cylinder 11. The exhaust passage 21 is connected to each cylinder 11. The catalyst 22 is located midway through the exhaust passage 21. The catalyst 22 purifies the exhaust gas.

[0016] The internal combustion engine 10 has an air flow meter 61, a water temperature sensor 63, and a crank angle sensor 64. The air flow meter 61 is located upstream of the throttle valve 16 in the intake passage 15. The air flow meter 61 detects the amount of intake air GA flowing into the intake passage 15. The water temperature sensor 63 is located at the outlet of the water jacket 18. The water temperature sensor 63 detects the temperature TW of the cooling water. The crank angle sensor 64 is located near the crankshaft 31. The crank angle sensor 64 detects the rotational position CR of the crankshaft 31. The air flow meter 61, the water temperature sensor 63, and the crank angle sensor 64 output signals according to the information detected by each of them.

[0017] The vehicle 500 has an automatic transmission 50. The automatic transmission 50 has an input shaft 52, an output shaft 54, a plurality of engagement elements 53, a plurality of planetary gear mechanisms, and a hydraulic circuit 55. The input shaft 52 is connected to the crankshaft 31. The output shaft 54 ​​is connected to wheels 60 via a differential or the like. The plurality of engagement elements 53 and the plurality of planetary gear mechanisms are interposed between the input shaft 52 and the output shaft 54. The plurality of engagement elements 53 are either a clutch or a brake. The engagement and disengagement states of each engagement element 53 are switched according to the hydraulic pressure of the hydraulic circuit 55. By switching the engagement and disengagement states of each engagement element 53, the automatic transmission 50 can form a gear stage corresponding to one of four preset shift ranges. The four shift ranges are a parking range, a neutral range, a drive range, and a reverse range. The parking range and neutral range are shift ranges that form gear stages for non-driving of the vehicle 500. The drive range and reverse range are shift ranges that form gear stages for driving of the vehicle 500. In particular, the drive range is a shift range that forms a gear stage for forward driving of the vehicle 500. The reverse range is a shift range that forms a gear stage for reverse driving of the vehicle 500.

[0018] The vehicle 500 has a shift lever 82. The shift lever 82 is located within the passenger compartment of the vehicle 500. The shift lever 82 is a lever that can be switched by an occupant to one of four predetermined operating positions. Each operating position corresponds to a different shift range in the automatic transmission 50.

[0019] The vehicle 500 has an accelerator pedal 94 and a brake pedal 95. The accelerator pedal 94 and the brake pedal 95 are foot pedals that are depressed by a vehicle occupant. The vehicle 500 has a shift position sensor 84, an accelerator sensor 87, a brake sensor 88, and a vehicle speed sensor 89. The shift position sensor 84 detects the operation position of the shift lever 82 as a lever position LV. The accelerator sensor 87 detects the depression amount of the accelerator pedal 94 as an accelerator operation amount ACC. The brake sensor 88 detects the depression amount of the brake pedal 95 as a brake operation amount BK. The vehicle speed sensor 89 detects the traveling speed of the vehicle 500 as a vehicle speed SP. Each of the above sensors outputs a signal according to the information detected by it.

[0020] The vehicle 500 has an ignition switch 99. The ignition switch 99 is a switch for starting the vehicle 500. The ignition switch 99 is turned on or off by an operation by a passenger. The ignition switch 99 outputs a signal Y corresponding to whether the ignition switch 99 is on or off.

[0021] <Overview of the control device> The vehicle 500 includes a control device 100. The control device 100 may be configured as one or more processors that execute various processes according to a computer program (software). The control device 100 may be configured as one or more dedicated hardware circuits, such as an application specific integrated circuit (ASIC), that execute at least a part of the various processes, or a circuit including a combination thereof. The processor includes a CPU 102 and memories such as a RAM and a ROM 104. The memory stores program codes or instructions that are configured to cause the CPU 102 to execute processes. The memory, i.e., a computer-readable medium, includes any available medium that can be accessed by a general-purpose or dedicated computer. The control device 100 also includes a storage device 106, which is an electrically rewritable non-volatile memory.

[0022] The control device 100 receives a signal Y from the ignition switch 99. The control device 100 also receives detection signals from various sensors attached to the vehicle 500. Specifically, the control device 100 receives detection signals for the following parameters:

[0023] - Intake volume GA detected by air flow meter 61 - Coolant temperature TW detected by the water temperature sensor 63 The rotational position CR of the crankshaft 31 detected by the crank angle sensor 64 Lever position LV detected by shift position sensor 84 Accelerator operation amount ACC detected by accelerator sensor 87 Brake operation amount BK detected by the brake sensor 88 Vehicle speed SP detected by the vehicle speed sensor 89 The control device 100 controls the automatic transmission 50. The control device 100 switches the shift range of the automatic transmission 50 in accordance with the lever position LV.

[0024] The control device 100 controls the internal combustion engine 10. For example, the control device 100 controls the ignition timing F of the spark plug 19, the opening OP of the throttle valve 16, and the amount of fuel J injected by the fuel injection valve 17. In this embodiment, the ignition timing F of the spark plug 19 is handled as follows. That is, the compression top dead center of the cylinder 11 to be ignited is set to "0", and the ignition timing F set before the compression top dead center is set to a negative value, and the ignition timing F set after the compression top dead center is set to a positive value. Therefore, the value of the ignition timing F increases as it is set to the retarded side.

[0025] The control device 100 can execute a catalyst warm-up process as one of a plurality of processes for controlling the internal combustion engine 10. The catalyst warm-up process is a process for promoting the warm-up of the catalyst 22 during a cold start of the internal combustion engine 10. Here, the temperature TW of the cooling water when the ignition switch 99 is turned on is referred to as a start-up temperature TS. When the start-up temperature TS is equal to or lower than a specified temperature TK, the control device 100 performs the catalyst warm-up process while the vehicle 500 is stopped before starting to run. Note that, when the start-up temperature TS is low, it can be estimated that the temperature of the entire internal combustion engine 10, including the temperature of the engine body 10A, is low. Therefore, it can be estimated that the temperature 22T of the catalyst 22 is also low. The specified temperature TK is previously determined, for example, by an experiment or a simulation, as the maximum value of the start-up temperatures TS at which the catalyst 22 cannot effectively perform the exhaust purification function.

[0026] In the catalyst warm-up process, the control device 100 corrects the ignition timing F of the spark plug 19 to the retarded side with respect to the compression top dead center, and increases the engine speed NE, which is the rotation speed of the crankshaft 31. By doing so, the control device 100 promotes the warm-up of the catalyst 22. Note that when the ignition timing F is retarded, the conversion efficiency of the thermal energy generated by the combustion of the mixture in the cylinder 11 to mechanical energy decreases. Then, the thermal energy transmitted to the exhaust increases. Therefore, the exhaust is likely to become hot. When this hot exhaust reaches the catalyst 22, the warm-up of the catalyst 22 can be promoted. Also, when the engine speed NE is increased, the exhaust is likely to become hot in response to the friction of the piston. When this hot exhaust reaches the catalyst 22, the warm-up of the catalyst 22 can be promoted.

[0027] Now, while retarding the ignition timing F of the spark plug 19 or increasing the engine speed NE can promote the warming up of the catalyst 22, there is the following trade-off. That is, when the ignition timing F is retarded, the combustion state of the mixture in the cylinder 11 becomes unstable. Also, when the engine speed NE is increased, a large amount of fuel is consumed, and fuel economy deteriorates. In the catalyst warm-up process, the control device 100 advances the warm-up of the catalyst 22 while taking into consideration the combustion state of the mixture and fuel economy. Specifically, the control device 100 changes which of the warm-up speed of the catalyst 22, the combustion state of the mixture, and fuel economy to be prioritized, based on the correspondence with the shift range of the automatic transmission 50. Then, the ignition timing F of the spark plug 19 and the engine speed NE are changed according to the priority. The correspondence between the priority and the shift range will be described in the section on operation below.

[0028] <About the map> The control device 100 stores in advance a number of maps to be used when performing the catalyst warm-up process. These maps define target values ​​of various parameters required for controlling the internal combustion engine 10 during the catalyst warm-up process. Specifically, the various parameters are a target engine speed NE*, which is a target value of the engine speed NE, a target ignition timing F*, which is a target value of the ignition timing F, and a target intake air amount GA*, which is a target value of the intake air amount GA. The maps are prepared for each of three shift ranges, namely, a drive range, a reverse range, and a non-driving range. The non-driving range is a general term for the parking range and the neutral range. In the following description, the drive range and the reverse range may be collectively referred to as the driving range.

[0029] <Map for driving range> The control device 100 stores a first drive map in advance. The first drive map is a map for a drive range. In the first drive map, a target engine speed NE* is defined for each start-up temperature TS within a range of a predetermined start-up temperature TS in which the catalyst 22 needs to be warmed up. As shown by the dashed line in FIG. 2, the relationship between the start-up temperature TS and the target engine speed NE* in the first drive map is basically as follows. That is, the higher the start-up temperature TS, the lower the target engine speed NE*.

[0030] The relationship between the start-up temperature TS and the target engine speed NE* in the drive first map is determined taking into consideration the warm-up speed of the catalyst 22 required according to the start-up temperature TS and fuel economy. That is, when the start-up temperature TS is low, it is necessary to increase the engine speed NE to increase the warm-up speed of the catalyst 22. On the other hand, when the start-up temperature TS is high, the temperature of the catalyst 22 is already appropriately high, so it is permissible to suppress the warm-up speed of the catalyst 22. In other words, it is possible to suppress the engine speed NE and improve fuel economy accordingly. Taking these circumstances into consideration, in the drive first map, the higher the start-up temperature TS, the lower the target engine speed NE*.

[0031] The control device 100 stores a second drive map in advance. The second drive map is a map for a drive range, similar to the first drive map. In the second drive map, a target ignition timing F* is determined for each start-up temperature TS within a range of a predetermined start-up temperature TS in which the catalyst 22 needs to be warmed up. As shown by the dashed line in FIG. 3, the relationship between the start-up temperature TS and the target ignition timing F* in the second drive map is basically as follows. That is, the higher the start-up temperature TS, the more advanced the target ignition timing F* is.

[0032] The relationship between the start-up temperature TS and the target ignition timing F* in the second drive map is determined taking into consideration the warm-up speed of the catalyst 22 required according to the start-up temperature TS and the combustion state of the mixture. That is, when the start-up temperature TS is low, it is necessary to increase the delay amount of the ignition timing F to increase the warm-up speed of the catalyst 22. On the other hand, when the start-up temperature TS is high, since the temperature 22T of the catalyst 22 is already relatively high, it is permissible to suppress the warm-up speed of the catalyst 22. That is, it is possible to suppress the delay amount of the ignition timing F and accordingly stabilize the combustion state of the mixture. In consideration of these circumstances, in the second drive map, the higher the start-up temperature TS, the more advanced the target ignition timing F* is.

[0033] The target ignition timing F* in the drive second map is determined as a value obtained by correcting the ignition timing F to the retard side with respect to the basic ignition timing FB for each starting temperature TS. The basic ignition timing FB for each starting temperature TS is the MBT ignition timing according to the target engine speed NE* defined in the drive first map. The MBT ignition timing is the ignition timing F that can obtain the maximum torque in the current engine operating state. Here, within the range of the target engine speed NE* for each starting temperature TS defined in the drive first map, there is not much difference in the MBT ignition timing. Therefore, the basic ignition timing FB for each starting temperature TS is approximately the same. This means the following. In other words, the larger the positive value of the target ignition timing F* defined in the drive second map is, that is, the more retarded the value is, the larger the correction amount to the retard side from the basic ignition timing FB is. The target ignition timing F* defined in the second drive map is a timing that is retarded from the compression top dead center because it is a value corrected to the retard side from the MBT ignition timing. Strictly speaking, the MBT ignition timing changes somewhat depending on the engine load and other factors in addition to the engine speed NE, but the difference due to the engine load and other factors is small. Therefore, when determining the MBT ignition timing according to the target engine speed NE*, it is sufficient to assume a certain constant value for the engine load and other factors.

[0034] The control device 100 stores a drive third map in advance. The drive third map is a map for a drive range, similar to the drive first map and the drive second map. In the drive third map, a target intake air amount GA* is determined for each start-up temperature TS within a range of a predetermined start-up temperature TS in which the catalyst 22 needs to be warmed up. This target intake air amount GA* is determined as follows in relation to the drive first map and the drive second map. For example, in the drive first map, the target engine speed NE* is set to a second value when the start-up temperature TS is a first value. Also, in the drive second map, the target ignition timing F* is set to a third value when the start-up temperature TS is a first value. In this case, the target intake air amount GA* when the start-up temperature TS is a first value is determined as the intake air amount GA required to maintain the target engine speed NE* at the second value when the target ignition timing F* is a third value. In this manner, the target intake air volume GA* is determined for each starting temperature TS.

[0035] <Map for reverse range> The control device 100 stores a reverse first map in advance. The reverse first map is a map for the reverse range. In the reverse first map, as in the drive first map, a target engine speed NE* is determined for each start-up temperature TS within a range of a predetermined start-up temperature TS in which the catalyst 22 needs to be warmed up. The relationship between the start-up temperature TS and the target engine speed NE* in the reverse first map is the same as that in the drive first map. That is, as shown by the solid line in FIG. 2, in the reverse first map, the higher the start-up temperature TS, the lower the target engine speed NE*. Note that, as shown in FIG. 2, when compared at the same start-up temperature TS, the target engine speed NE* in the reverse first map shown by the solid line is lower than the target engine speed NE* in the drive first map shown by the dashed line. The reason for this will be explained in the section on operation to be described later.

[0036] The control device 100 stores the reverse second map in advance. The reverse second map is a map for the reverse range, similar to the reverse first map. In the reverse second map, the target ignition timing F* is determined for each start-up temperature TS within a range of a predetermined start-up temperature TS where the catalyst 22 needs to be warmed up, similar to the drive second map. The relationship between the start-up temperature TS and the target ignition timing F* in the reverse second map is the same as that in the drive second map. That is, as shown by the solid line in FIG. 3, in the reverse second map, the higher the start-up temperature TS, the more advanced the target ignition timing F* is. Note that, similar to the drive second map, the target ignition timing F* in the reverse second map is determined as a value obtained by correcting the ignition timing F to the retard side with respect to the basic ignition timing FB. Also, the target ignition timing F* in the reverse second map is retarded from the compression top dead center.

[0037] As shown in FIG. 3, when compared at the same starting temperature TS, the target ignition timing F* in the reverse second map shown by the solid line is more advanced than the target ignition timing F* in the drive second map shown by the dashed line. The reason for this will be explained in the section on operation below. Here, the correction amount from the basic ignition timing FB to the retard side for the target ignition timing F* in the reverse second map is called the reverse correction amount. Also, the correction amount from the basic ignition timing FB to the retard side for the target ignition timing F* in the drive first map is called the drive correction amount. When compared at the same starting temperature TS, the reverse correction amount and the drive correction amount have the following relationship. As a premise, when compared at the same starting temperature TS, the basic ignition timing FB determined from the target engine speed NE* in the reverse first map and the basic ignition timing FB determined from the target engine speed NE* in the drive first map are approximately the same. Therefore, the reverse correction amount and the drive correction amount have a relationship in which the former is smaller than the latter.

[0038] The control device 100 stores a reverse third map in advance. The reverse third map is a map for the reverse range, similar to the reverse first and second maps. In the reverse third map, similar to the drive third map, a target intake air amount GA* is defined for each start-up temperature TS within a range of a predetermined start-up temperature TS in which the catalyst 22 needs to be warmed up. The target intake air amount GA* in the reverse third map is defined from the same perspective as the drive third map.

[0039] <Map for non-driving range> The control device 100 stores a non-driving first map in advance. The non-driving first map is a map for a non-driving range. In the non-driving first map, the target engine speed NE* is determined for each start-up temperature TS within a range of a predetermined start-up temperature TS in which the catalyst 22 needs to be warmed up, as in the drive first map. The relationship between the start-up temperature TS and the target engine speed NE* in the non-driving first map is the same as that in the drive first map. That is, as shown by the two-dot chain line in FIG. 2, in the non-driving first map, the higher the start-up temperature TS, the lower the target engine speed NE*. Note that, as shown in FIG. 2, when compared at the same start-up temperature TS, the target engine speed NE* in the non-driving first map shown by the two-dot chain line is higher than the target engine speed NE* in the drive first map shown by the one-dot chain line. The reason for this will be explained in the section on operation described later.

[0040] The control device 100 stores the non-driving second map in advance. The non-driving second map is a map for the non-driving range, similar to the non-driving first map. In the non-driving second map, the target ignition timing F* is determined for each start-up temperature TS within a range of a predetermined start-up temperature TS where the catalyst 22 needs to be warmed up, similar to the drive second map. The relationship between the start-up temperature TS and the target ignition timing F* in the non-driving second map is the same as that in the drive second map. That is, as shown by the two-dot chain line in FIG. 3, in the non-driving second map, the higher the start-up temperature TS, the more advanced the target ignition timing F* is. In the non-driving second map, the target ignition timing F* is determined as a value obtained by correcting the ignition timing F to the retard side with respect to the basic ignition timing FB, similar to the drive second map. In addition, the target ignition timing F* in the non-driving second map is retarded from the compression top dead center. As shown in FIG. 3, when compared at the same starting temperature TS, the target ignition timing F* in the non-driving second map shown by the two-dot chain line is more retarded than the target ignition timing F* in the drive second map shown by the one-dot chain line. This means the following from the same viewpoint as explained in the comparison between the reverse second map and the drive second map. That is, when compared at the same starting temperature TS, the non-driving correction amount is larger than the drive correction amount. The non-driving correction amount is the correction amount from the basic ignition timing FB to the retard side with respect to the target ignition timing F* specified in the non-driving second map. The reason for the difference between the non-driving second map and the drive second map will be explained in the section on operation described later.

[0041] The control device 100 stores a non-driving third map in advance. The non-driving third map is a map for a non-driving range, similar to the non-driving first map and the non-driving second map. In the non-driving third map, similar to the drive third map, a target intake air amount GA* is defined for each start-up temperature TS within a range of a predetermined start-up temperature TS in which the catalyst 22 needs to be warmed up. The target intake air amount GA* in the non-driving third map is defined from the same perspective as the drive third map.

[0042] <Specific details of catalyst warm-up processing> When the ignition switch 99 is turned on, the control device 100 acquires the coolant temperature TW at that time as the start-up temperature TS. When the start-up temperature TS is higher than the above-mentioned specified temperature TK, the control device 100 performs normal idle processing. That is, in the normal idle processing, the control device 100 controls the internal combustion engine 10 so that the engine speed NE becomes the idle speed. The idle speed is predetermined as the minimum engine speed NE at which the internal combustion engine 10 can continue to operate independently.

[0043] On the other hand, when the start-up temperature TS is equal to or lower than the specified temperature TK, the control device 100 starts the catalyst warm-up process. When the control device 100 starts the catalyst warm-up process, the control device 100 starts calculating the integrated intake air amount GAs, which is the integrated value of the intake air amount GA since the ignition switch 99 is turned on.

[0044] As shown in Fig. 4, when the control device 100 starts the catalyst warm-up process, it first executes the process of step S10. In step S10, the control device 100 determines the current shift range of the automatic transmission 50. The control device 100 makes this determination based on the latest lever position LV or the control content related to the automatic transmission 50. When the control device 100 determines the shift range of the automatic transmission 50, it proceeds to step S20.

[0045] In step S20, the control device 100 reads out a map corresponding to the shift range determined in step S10. For example, if the shift range determined in step S10 is the drive range, the control device 100 reads out a drive first map, a drive second map, and a drive third map. Here, the case where the shift range is the drive range is taken as an example, but in the case of other shift ranges, the map corresponding to the shift range may be read out in a similar manner. After reading out the map corresponding to the shift range, the control device 100 advances the process to step S30.

[0046] In step S30, the control device 100 calculates each target value based on the map read in step S20. For example, it is assumed that the maps read in step S20 are the drive first map, the drive second map, and the drive third map. In this case, the control device 100 calculates the target engine speed NE* corresponding to the start-up temperature TS based on the drive first map. The control device 100 also calculates the target ignition timing F* corresponding to the start-up temperature TS based on the drive second map. The control device 100 also calculates the target intake air amount GA* corresponding to the start-up temperature TS based on the drive third map. After calculating the target intake air amount GA*, the control device 100 calculates the opening degree OP of the throttle valve 16 required to realize the target intake air amount GA* as the target opening degree OP*. After calculating the target intake air amount GA*, the control device 100 also calculates the target value of the fuel amount J injected from the fuel injection valve 17 as the target fuel amount J*. At this time, the control device 100 calculates the target fuel amount J* so that the air-fuel ratio in the cylinder 11 becomes the theoretical air-fuel ratio. The control device 100 stores in advance, for example, a map showing the relationship between the intake air amount GA and the opening degree OP of the throttle valve 16. The control device 100 calculates the target opening degree OP* based on this map. The control device 100 also stores in advance a map showing the relationship between the intake air amount GA and the fuel amount J required to make the air-fuel ratio the theoretical air-fuel ratio. The control device 100 calculates the target fuel amount J* based on this map. Although the above description has been given by taking the example of the shift range being the drive range, each target value may be calculated in a similar manner in the case of other shift ranges. After calculating each target value, the control device 100 advances the process to step S40.

[0047] In step S40, the control device 100 controls various parts of the internal combustion engine 10 based on the target values ​​calculated in step S30. Specifically, the control device 100 controls the spark plug 19 so that ignition occurs at the target ignition timing F*. The control device 100 also controls the throttle valve 16 so that the opening OP of the throttle valve 16 becomes the target opening OP*. The control device 100 also controls the fuel injector 17 so that the target fuel amount J* of fuel is injected. After controlling the various parts of the internal combustion engine 10 for a predetermined control period, the control device 100 advances the process to step S50.

[0048] In step S50, the control device 100 judges whether or not a termination condition is met. The termination condition is that at least one of the following items (A) and (B) is met. (a) The shift range of the automatic transmission 50 is the drive range, and the brake operation amount BK is equal to or less than a specified operation amount.

[0049] (b) The cumulative intake air volume GAs since the ignition switch 99 was turned on is equal to or greater than a judgment value. Regarding item (A), the prescribed operation amount is a brake operation amount BK at which the brake pedal 95 can be regarded as being released, and is determined in advance, for example, by experiment or simulation. Here, a situation in which item (A) is satisfied will be described along with a series of flows after the ignition switch 99 is turned on. The shift range of the automatic transmission 50 is the non-driving range when the ignition switch 99 is turned on. When the occupant starts driving the vehicle 500, the occupant switches the shift range to the driving range while depressing the brake pedal 95 prior to the start of driving. After that, when the occupant releases the brake pedal 95, the vehicle 500 starts driving. The situation in which the above item (A) is satisfied is a situation in which the occupant releases the brake pedal 95 to start driving the vehicle 500, that is, a situation in which the occupant issues an instruction to start driving.

[0050] Regarding the above item (ii), the cumulative intake air amount GAs correlates with the total amount of thermal energy generated by the combustion of the air-fuel mixture in the cylinder 11 after the start of the internal combustion engine 10. That is, it can be estimated that the larger the cumulative intake air amount GAs, the higher the temperature of the engine body 10A is due to the heat accompanying the combustion of the air-fuel mixture. If the temperature of the engine body 10A is rising, it can be estimated that the temperature of the exhaust gas is also rising, and accordingly, the temperature 22T of the catalyst 22 in the exhaust passage 21 is also rising. Here, the temperature near the center of the temperature range in which the catalyst 22 is activated (hereinafter referred to as the activation temperature range) is referred to as the representative temperature. The judgment value in the above item (ii) is the cumulative intake air amount GAs at which the temperature 22T of the catalyst 22 is considered to have reached the representative value, and is determined in advance, for example, by experiment or simulation. The situation in which the above item (ii) is satisfied is a situation in which the catalyst 22 reaches the activation temperature and warming up is completed.

[0051] The control device 100 determines whether or not the termination condition is met by referring to the shift range determined in step S10, the latest brake operation amount BK, and the latest integrated intake air amount GAs. If the termination condition is not met (step S50: NO), the control device 100 returns to the process of step S10. In this case, the control device 100 performs the processes from step S10 to step S50 again. The control device 100 repeats the processes from step S10 to step S50 until the termination condition is met. If the termination condition is met (step S50: YES), the control device 100 ends the catalyst warm-up process.

[0052] The process that the control device 100 performs after the catalyst warm-up process differs depending on which of the above items (A) and (B) is satisfied to establish the end condition. If the end condition is established because item (A) is not satisfied but item (B) is satisfied, the warm-up of the catalyst 22 is completed before the passenger issues an instruction to start driving the vehicle 500. In this case, since there is no instruction to start driving the vehicle 500, the control device 100 performs the normal idle process described above.

[0053] On the other hand, if the end condition is established by satisfying (a) but not (b) of items (a) and (b), the occupant has instructed the vehicle 500 to start running before the warm-up of the catalyst 22 is completed. In this case, the control device 100 executes a process for running related to the internal combustion engine 10 after the catalyst warm-up process is completed. In this process for running, the control device 100 calculates the required torque of the internal combustion engine 10 based on, for example, the vehicle speed SP and the accelerator operation amount ACC. Then, the control device 100 controls the internal combustion engine 10 based on the required torque. However, if the end condition is established by satisfying (a) but not (b), the warm-up of the catalyst 22 is not completed. Therefore, the control device 100 sets the ignition timing F of the spark plug 19 to a timing on the retard side of the basic ignition timing FB according to the engine operating state until the warm-up of the catalyst 22 is completed. This continues the promotion of the warm-up of the catalyst 22. If the ignition timing F is retarded from the basic ignition timing FB, the torque of the internal combustion engine 10 decreases. Therefore, the amount of retardation in this case is limited to a value that satisfies the required torque.

[0054] When the end conditions are established by simultaneously satisfying both items (A) and (B), the driver instructs the vehicle 500 to start traveling after the catalyst 22 has been warmed up. In this case, the control device 100 performs the above-described process for traveling without considering the warming up of the catalyst 22.

[0055] <Operation of the embodiment> (A) Differences in map settings between non-driving range and driving range As shown in Fig. 2, when compared at the same start-up temperature TS, the target engine speed NE* in the non-driving range is higher than the target engine speed NE* in the driving range. Also, as shown in Fig. 3, when compared at the same start-up temperature TS, the target ignition timing F* in the non-driving range is more retarded than the target ignition timing F* in the driving range. The reason for adopting such a setting will be explained.

[0056] Here, consider a situation where the item (A) is satisfied and the end condition is established, that is, a situation where the end condition is established by the occupant instructing the vehicle 500 to start traveling. In this case, as described above, the control device 100 performs the traveling process after terminating the catalyst warm-up process. Now, in the case where the item (A) is satisfied and the end condition is established, the shift range of the automatic transmission 50 is switched from the non-driving range to the driving range during the execution of the catalyst warm-up process. This is because, as described above, the shift range is the non-driving range when the ignition switch 99 is turned on, and the occupant then switches the shift range to the traveling direction that he or she intends. Since the shift range is switched from the non-driving range to the driving range during the execution of the catalyst warm-up process, the execution period of the catalyst warm-up process includes a period in which the shift range is the non-driving range and a period in which the shift range is the driving range. Of these, the latter period is a period that transitions to the traveling process. Here, when switching from the catalyst warm-up process to the running process, it is required to smoothly start the running of the vehicle 500 without suddenly changing the ignition timing F, for example. To achieve this, it is necessary to set the target ignition timing F* in the latter period in consideration of the ignition timing F required in the running process. In other words, in consideration of the switching to the running process, there are restrictions on the settable value of the target ignition timing F* of the catalyst warm-up process when the shift range is the running range. The same can be said for the target engine speed NE*.

[0057] On the other hand, there is no restriction on each target value in the former period, i.e., each target value when the shift range is the non-driving range, considering the switching to the driving process. This is because when the shift range is the non-driving range, a situation does not occur in which the control of the internal combustion engine 10 is switched from the catalyst warm-up process to the driving process. Therefore, for the non-driving range, the target engine speed NE* and the target ignition timing F* can be set freely to a certain extent.

[0058] Here, the catalyst warm-up process is a process for promoting the warm-up of the catalyst 22. For this reason, among the factors to be considered when executing the catalyst warm-up process, such as the warm-up speed of the catalyst 22, the combustion state of the air-fuel mixture, and fuel consumption, it is necessary to set the warm-up speed of the catalyst 22 as a priority. As described above, even if each target value is set in the running range to increase the warm-up speed of the catalyst 22, there is a limit to the values ​​that can be set in relation to the above constraints. In contrast, in the non-running range, the range of values ​​that can be set as each target value is wide. Therefore, in the non-running range, in order to increase the warm-up speed of the catalyst 22 as much as possible, the target engine speed NE* is set higher and the target ignition timing F* is set to a retarded timing compared to the running range.

[0059] (B) Differences in map settings between drive range and reverse range As described above, the map for the non-driving range is set, and within the driving range, the map settings are different for the drive range and reverse range. That is, as shown in FIG. 2, when compared at the same starting temperature TS, the target engine speed NE* in the reverse range is lower than the target engine speed NE* in the drive range. Also, as shown in FIG. 3, when compared at the same starting temperature TS, the target ignition timing F* in the reverse range is more advanced than the target ignition timing F* in the drive range. The reason for adopting such settings will be explained.

[0060] As a premise, when the vehicle 500 moves backward, the required output of the internal combustion engine 10 is smaller and the amount of exhaust is smaller than when the vehicle 500 moves forward. Therefore, when the vehicle 500 moves backward, the exhaust purification ability of the catalyst 22 may be lower than when the vehicle 500 moves forward.

[0061] Now, assume that the catalyst warm-up process is being performed with the shift range of the automatic transmission 50 in the reverse range. In this case, there is a high possibility that the occupant will release the brake pedal 95 while the shift range is in the reverse range. In other words, there is a high possibility that the vehicle 500 will move backward. As described above, when moving backward, the exhaust purification ability is not required as much as when moving forward. Therefore, the exhaust purification ability of the catalyst 22 at the end of the catalyst warm-up process, that is, the temperature 22T of the catalyst 22, does not need to be so high as long as a certain value can be guaranteed. In addition, due to the setting of each target value of the non-driving range described above, it is expected that the temperature 22T of the catalyst 22 will be appropriately high at the stage before the shift range is switched to the reverse range, that is, during the period when the shift range is in the non-driving range. For this reason, when the shift range during the catalyst warm-up process is in the reverse range, it is acceptable to suppress the warm-up speed of the catalyst 22. Therefore, in the reverse range, the target engine speed NE* is set lower than that in the drive range when compared at the same start-up temperature TS. In addition, the target ignition timing F* is set to be more advanced than in the drive range. In other words, in the reverse range, the target values ​​are set to prioritize stabilizing the combustion state of the air-fuel mixture and improving fuel efficiency, compared to the drive range.

[0062] For the above reasons, different target engine speeds NE* and target ignition timings F* are set for the drive range, reverse range, and non-driving range. The target engine speeds NE* and target ignition timings F* for each shift range may be appropriately determined, for example, by experiment or simulation, so that the catalyst 22 is heated to the activation temperature range before the vehicle 500 starts to drive. In this case, for example, a value that can be considered as a general value is calculated in advance for the length of time from when the ignition switch 99 is turned on until the driver issues an instruction to start driving the vehicle 500. For example, an average value for the length of time until the driver issues an instruction to start driving the vehicle 500 is calculated using multiple riding opportunities for multiple drivers as samples. Then, using the length of time as a reference, the speed of warming up the catalyst 22 required to heat the catalyst 22 to the activation temperature range within that time is calculated backwards, and each target value is determined from that value. In particular, the target values ​​in the non-driving range should be set so that the temperature 22T of the catalyst 22 quickly reaches near the lower limit TB of the activation temperature range within the period during which the catalyst warm-up process is performed in the non-driving range.

[0063] (C) Example of catalyst temperature change over time due to catalyst warm-up process By setting each map as described above, it is possible to warm up the catalyst 22 as follows. Here, a case is taken as an example in which, after the ignition switch 99 is turned on, the occupant instructs the vehicle 500 to start running before the catalyst 22 has finished warming up, and the catalyst warm-up process ends.

[0064] As shown in FIG. 5, it is assumed that the ignition switch 99 is turned on at time t1. It is assumed that the start-up temperature TS, which is the temperature TW of the cooling water at this time, is equal to or lower than the specified value TK. In this case, the control device 100 starts the catalyst warm-up process. Now, the shift range of the automatic transmission 50 at the time when the ignition switch 99 is turned on is the non-driving range. Therefore, the control device 100 calculates each target value based on the map for the non-driving range (steps S20 and S30). Then, the control device 100 controls the internal combustion engine 10 based on each calculated target value (step S40). As described above, in the map for the non-driving range, the target engine rotation speed NE* is appropriately high, and the target ignition timing F* is appropriately retarded. By controlling the internal combustion engine 10 based on these target values, the catalyst 22 is heated at a first speed A1S, which is a relatively high speed, as shown by the solid line A1 in FIG. 5. Then, the temperature 22T of the catalyst 22 quickly rises to a value near the lower limit value TB of the activation temperature range, for example.

[0065] At time t2 after time t1, the driver switches the shift range of the automatic transmission 50 from the non-driving range to the reverse range. Then, from this point on, the control device 100 calculates each target value based on the map for the reverse range (steps S20 and S30). Here, as described above, when compared at the same start-up temperature TS, in the map for the reverse range, the target engine rotation speed NE* is lower and the target ignition timing F* is on the advanced side compared to the map for the non-driving range. As the internal combustion engine 10 is controlled based on these target values ​​(step S40), as shown by the solid line A2 in FIG. 5, after time t2, the catalyst 22 is heated at a second speed A2S lower than the first speed A1S. In addition, in the map for the reverse range, the target engine rotation speed NE* is lower and the target ignition timing F* is on the advanced side compared to the map for the drive range. Therefore, the second speed A2S is lower than the temperature rise speed A3S of the catalyst 22 when the driver switches the shift range to the drive range at time t2, as indicated by the dashed dotted line A3 in FIG.

[0066] After time t2, the temperature 22T of the catalyst 22 rises gradually and eventually exceeds the lower limit TB of the activation temperature range. Suppose that the occupant releases the brake pedal 95 at a later time t3. Then, item (i) is satisfied, and the end condition is established (step S50: YES). Then, the control device 100 ends the catalyst warm-up process and starts the process for driving. At the same time, the vehicle 500 starts to move in reverse. At this time, the temperature 22T of the catalyst 22 is a value within the activation temperature range. Therefore, while the vehicle 500 is moving in reverse, the catalyst 22 functions appropriately and purifies the exhaust gas.

[0067] As in this example, due to the setting of each target value in the map for the reverse range, if the occupant intends to reverse when the vehicle 500 starts to travel, there may be many occasions where the occupant issues a command to start traveling of the vehicle 500 before the warm-up of the catalyst 22 is completed, and the end condition is satisfied. However, when the vehicle 500 is reversed, it is sufficient that the temperature 22T of the catalyst 22 reaches the lower limit value TB of the activation temperature range. In addition, according to the setting of the map for the non-traveling range described above, the temperature of the catalyst 22 can be quickly increased during the non-traveling range. Therefore, even if the warm-up of the catalyst 22 is not completed when the vehicle 500 starts to reverse, the necessary exhaust purification performance of the catalyst 22 can be reliably guaranteed.

[0068] In the above, an example was given of a case where the temperature 22T of the catalyst 22 has not yet reached the lower limit TB of the activation temperature range when the shift range is switched to the reverse range. However, depending on the timing of switching the shift range and how each target value is defined in the non-driving map, the temperature 22T of the catalyst 22 may be above the lower limit TB when the shift range is switched to the reverse range. Also, it is possible that item (ii) is satisfied instead of item (i), i.e., the warm-up of the catalyst 22 is completed before the occupant issues a command to start driving the vehicle 500, and the end condition is established.

[0069] <Effects of the embodiment> The speed of warming up the catalyst 22 required in the catalyst warm-up process differs for each shift range, depending on the order of shift range switching during the period from when the ignition switch 99 is turned on until the vehicle 500 starts running, and the amount of exhaust gas after the vehicle starts running. In consideration of this point, in this embodiment, the contents to be prioritized during the catalyst warm-up process with respect to the warm-up speed of the catalyst 22, the combustion state of the mixture, and fuel efficiency are changed according to the shift range. That is, in the non-driving range where there is no restriction associated with switching to the driving process and where quick warm-up of the catalyst 22 is required, the speed of warming up the catalyst 22 is prioritized. On the other hand, in the reverse range where it is permitted to suppress the exhaust purification ability while the vehicle 500 is running, the combustion state of the mixture and fuel efficiency are prioritized. In this way, by changing the priority contents for each shift range, it is possible to suppress the instability of the combustion state of the mixture and the deterioration of fuel efficiency while ensuring the necessary function of the catalyst 22.

[0070] <Example of change> This embodiment can be modified as follows: This embodiment and the following modifications can be combined with each other to the extent that there is no technical contradiction.

[0071] The content of item (A) of the termination condition is not limited to the example of the above embodiment. For example, the content that the accelerator operation amount ACC is greater than zero may be added to the content of item (A) of the above embodiment. That is, the catalyst warm-up process may be continued until it is confirmed that the vehicle 500 has definitely started traveling. The content of a similar viewpoint may be determined by the vehicle speed SP instead of or in addition to the accelerator operation amount ACC. Item (A) may be any item that can switch the control of the internal combustion engine 10 from the catalyst warm-up process to a process for traveling at an appropriate timing so as to satisfy the driving request of the occupant.

[0072] Item (ii) of the termination condition is not limited to the example of the above embodiment. Item (ii) may be any content that can specify the completion of warming up of the catalyst 22. For example, instead of or in addition to the integrated intake air amount GAs, the termination condition may be that the elapsed time since the ignition switch 99 was turned on exceeds a specified time. Also, instead of the integrated intake air amount GAs, an estimated value of the temperature of the catalyst 22 may be calculated, and the estimated value may be used to determine item (ii).

[0073] It is not essential to provide different settings between the non-driving range map and the driving range map as in the above embodiment. Regardless of the settings of the non-driving range map, by providing different settings between the drive range map and the reverse range map as in the above embodiment, it is possible to prevent the mixture combustion state from becoming unstable and the fuel economy from worsening at least during the catalyst warm-up process in the reverse range.

[0074] The catalyst warm-up process is not limited to be performed during the period from when the ignition switch 99 is turned on until the vehicle 500 starts to run. For example, the following mode may be adopted. As described above, the promotion of the warm-up of the catalyst 22 may be continued after the start of the process for running. The process at this time, that is, the process during the period during which the promotion of the warm-up of the catalyst 22 is continued among the processes for running, may be treated as the catalyst warm-up process for running. In this case, when the shift range of the automatic transmission 50 is the reverse range, the target ignition timing F* may be set to the advanced side and the target engine rotation speed NE* may be lowered compared to when the shift range is the drive range. By performing the catalyst warm-up process for running, the combustion state of the mixture can be stabilized and fuel economy can be improved during the period during which the vehicle 500 is actually running.

[0075] It is not essential to use the coolant temperature TW when determining whether or not to perform the catalyst warm-up process. For example, the outside air temperature may be used instead of the coolant temperature TW. In this case, a temperature sensor that detects the outside air temperature may be attached to the vehicle 500. Any parameter that is an index of the temperature of the catalyst 22 at the start of the internal combustion engine 10 can be used as a parameter for determining whether or not to perform the catalyst warm-up process.

[0076] As in the above modification, when a parameter other than the coolant temperature TW is used to determine whether or not to perform the catalyst warm-up process, the new parameter is referred to as the "other parameter." When using the other parameter, the target engine speed NE* and the target ignition timing F* may be set for each other parameter value in each map.

[0077] It is not essential to set the target engine speed NE* for each cooling water temperature TW or each of the above-mentioned other parameters. That is, regardless of the cooling water temperature TW or the value of the other parameters, the target engine speed NE* during the catalyst warm-up process may be a constant value. For example, in the case of the above-mentioned embodiment, if the end condition is satisfied, the catalyst warm-up process ends, and if the warm-up of the catalyst 22 is not completed by the catalyst warm-up process, the warm-up of the catalyst 22 is continued by the process for driving. Therefore, although there may be a difference in the required time according to the target engine speed NE*, the warm-up of the catalyst 22 can be completed regardless of the target engine speed NE*. Therefore, even if the target engine speed NE* is set to a constant value, there is no problem in completing the warm-up of the catalyst 22. Even if the target engine speed NE* is set to a constant value, when the shift range of the automatic transmission 50 is the reverse range, the target engine speed NE* may be set lower than when the shift range is the drive range. Although the target engine speed NE* has been used as an example here, the target ignition timing F* during the catalyst warm-up process may also be set to a constant value. In this case, when the shift range is the reverse range, the target ignition timing F* may be set to a timing on the more advanced side compared to when the shift range is the drive range.

[0078] In the above modified example, only one of the target engine speed NE* and the target ignition timing F* may be set to a constant value, or both may be set to constant values. The basic ignition timing FB is not limited to the MBT ignition timing. For example, the basic ignition timing FB may be a value obtained by appropriately correcting the MBT ignition timing. The basic ignition timing FB may be any value that is appropriate as a reference for setting the target ignition timing F*.

[0079] The configuration of the internal combustion engine 10 is not limited to the example of the above embodiment. The internal combustion engine 10 only needs to have an ignition plug 19, a catalyst 22, and a crankshaft 31. For example, another catalyst may be provided downstream of the catalyst 22 in the exhaust passage 21.

[0080] The configuration of the automatic transmission 50 is not limited to the example of the above embodiment. The automatic transmission 50 may be configured to be able to switch the shift range to a drive range for moving the vehicle 500 forward or a reverse range for moving the vehicle 500 backward.

[0081] The overall configuration of the vehicle 500 is not limited to the example of the embodiment described above. The vehicle 500 may have the internal combustion engine 10 and the automatic transmission 50. For example, the vehicle 500 may have a motor generator in addition to the internal combustion engine 10 as a drive source of the vehicle 500. That is, the vehicle 500 may be configured as a hybrid vehicle. Even when the vehicle 500 is a hybrid vehicle, in promoting the warm-up of the catalyst 22, the target ignition timing F* may be set to an advanced timing and the target engine rotation speed NE* may be set to a lower timing when the shift range is the reverse range compared to when the shift range is the drive range. [Explanation of symbols]

[0082] 10. Internal combustion engine 11…Cylinder 19…Spark plug 22...Catalyst 31…Crankshaft 50…Automatic transmission 100...Control device 500…Vehicle

Claims

[Claim 1] The present invention is applied to a vehicle having an internal combustion engine equipped with a spark plug for igniting an engine in a cylinder, a catalyst for purifying exhaust gas, and a crankshaft, and an automatic transmission connected to the crankshaft and capable of switching a shift range to a drive range for moving the vehicle forward, a reverse range for moving the vehicle backward, or a non-driving range, A catalyst warm-up process can be executed to promote warm-up of the catalyst by retarding the ignition timing of the spark plug from the top dead center of compression. During execution of the catalyst warm-up process, when the shift range of the automatic transmission is the reverse range, the ignition timing of the spark plug is advanced and the engine rotation speed is reduced compared to when the shift range is the drive range; During the execution of the catalyst warm-up process, when the shift range of the automatic transmission is the non-driving range, the ignition timing of the spark plug is retarded and the engine rotation speed is increased compared to when the shift range is the drive range. Vehicle control device.

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