Control device for internal combustion engines

Abstract

The present invention provides a control device for an internal combustion engine that can prevent excessive correction by separately performing corrections based on intake air temperature and atmospheric pressure. [Solution] The control device for an internal combustion engine is a control device for an internal combustion engine capable of acquiring intake air temperature and atmospheric pressure, which determines a control value for controlling the operating state of the internal combustion engine, acquires an intake air temperature correction amount which is a correction amount for the control value based on the intake air temperature, acquires an atmospheric pressure correction amount which is a correction amount for the control value based on the atmospheric pressure, and performs correction control to correct the control value using the intake air temperature correction amount and the atmospheric pressure correction amount, wherein the intake air temperature correction amount is calculated using at least the intake air temperature and the atmospheric pressure as parameters, the atmospheric pressure correction amount is calculated using at least the intake air temperature and the atmospheric pressure as parameters, the intake air temperature correction amount corrects the control value in one direction of increase or decrease when the intake air temperature is high and the atmospheric pressure is high, and the atmospheric pressure correction amount corrects the control value in the other direction of increase or decrease when the intake air temperature is high and the atmospheric pressure is high.

Description

Technical Field

[0001] The present disclosure relates to a control device for an internal combustion engine.

Background Art

[0002] Conventionally, a control device that corrects the output value of an internal combustion engine using atmospheric pressure and intake air temperature has been known (see, for example, Patent Document 1). The control device for the internal combustion engine of Patent Document 1 stores a map that records the ignition delay amount corresponding to atmospheric pressure and intake air temperature. The control device for the internal combustion engine of Patent Document 1 fits the detected intake air temperature and atmospheric pressure to the map to obtain the ignition delay amount. The control device for the internal combustion engine of Patent Document 1 corrects the fuel injection timing based on the ignition delay amount.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] In the control device for the internal combustion engine of Patent Document 1, the correction amount corresponding to the detected intake air temperature and atmospheric pressure is determined from the map. However, since the correction by intake air temperature and the correction by atmospheric pressure have different purposes, it is preferable to execute them separately. In this case, it is preferable to prevent overcorrection caused by the overlap of the correction by intake air temperature and the correction by atmospheric pressure.

[0005] An object of the present disclosure is to provide a control device for an internal combustion engine that can prevent overcorrection while separately executing correction by intake air temperature and correction by atmospheric pressure.

Means for Solving the Problems

[0006] The control device for an internal combustion engine according to this disclosure is a control device for an internal combustion engine capable of acquiring intake air temperature and atmospheric pressure, which determines a control value for controlling the operating state of the internal combustion engine, acquires an intake air temperature correction amount which is a correction amount for the control value based on the intake air temperature, acquires an atmospheric pressure correction amount which is a correction amount for the control value based on the atmospheric pressure, and performs correction control to correct the control value using the intake air temperature correction amount and the atmospheric pressure correction amount, wherein the intake air temperature correction amount is calculated using at least the intake air temperature and the atmospheric pressure as parameters, the atmospheric pressure correction amount is calculated using at least the intake air temperature and the atmospheric pressure as parameters, the intake air temperature correction amount corrects the control value in one direction of increase or decrease when the intake air temperature is high and the atmospheric pressure is high, and the atmospheric pressure correction amount corrects the control value in the other direction of increase or decrease when the intake air temperature is high and the atmospheric pressure is high. [Effects of the Invention]

[0007] According to this internal combustion engine control system, the control system separately acquires the intake air temperature correction amount and the atmospheric pressure correction amount. Since the intake air temperature correction amount is calculated using atmospheric pressure as a parameter, the intake air temperature correction amount becomes a correction amount corresponding to changes in atmospheric pressure. Similarly, since the atmospheric pressure correction amount is calculated using intake air temperature as a parameter, the atmospheric pressure correction amount becomes a correction amount corresponding to changes in intake air temperature. As a result, this internal combustion engine control system can prevent excessive correction by separately performing corrections based on intake air temperature and atmospheric pressure. [Brief explanation of the drawing]

[0008] [Figure 1] A system diagram of a control device for an internal combustion engine according to a first embodiment of the present disclosure. [Figure 2] A diagram showing the process for determining the corrected control amount according to the first embodiment of this disclosure. [Figure 3] A figure showing an example of a control amount map, an intake air temperature correction amount map, and an atmospheric pressure correction amount map according to the first embodiment of this disclosure. [Figure 4] A figure showing an example of a map of intake air temperature correction coefficients and atmospheric pressure correction coefficients according to the first embodiment of this disclosure. [Figure 5]A diagram showing the process for determining the corrected control amount according to the second embodiment of this disclosure. [Figure 6] A figure showing an example of a first intake air temperature-based correction amount map, a second intake air temperature-based correction amount map, and an intake air temperature correction table according to a second embodiment of the present disclosure. [Figure 7] A figure showing an example of a first atmospheric pressure-based correction amount map, a second atmospheric pressure-based correction amount map, and an atmospheric pressure correction coefficient table according to a second embodiment of the present disclosure. [Figure 8] A figure showing an example of a map switching coefficient map according to a second embodiment of this disclosure. [Modes for carrying out the invention]

[0009] <First Embodiment> The first embodiment of this disclosure will be described below with reference to the drawings.

[0010] As shown in Figure 1, the internal combustion engine E comprises a fuel injector 2, an intake air temperature sensor 4, an atmospheric pressure sensor 6, and an accelerator pedal 8. The control device 1 is a device that controls the internal combustion engine E. The internal combustion engine E in this embodiment is mounted on a vehicle. In this embodiment, the internal combustion engine E is a four-stroke diesel engine that injects fuel directly into the cylinder N and causes autoignition.

[0011] The fuel injector 2 performs fuel injection to supply fuel to cylinder N. In this embodiment, the fuel injector 2 is connected to a fuel injection pump and an accumulator such as a common rail. The fuel injector 2 is electrically connected to a control device 1, and the injection amount is controlled by the control device 1. In this embodiment, the fuel injector 2 is capable of performing pilot injection, pre-injection, main injection, after-injection, and post-injection.

[0012] The intake air temperature detection device 4 is located in the intake manifold (or similar) connected to the intake port 12 and detects the intake air temperature T, which is the temperature of the air flowing into the cylinder N. In this embodiment, the intake air temperature detection device 4 is an intake air temperature sensor attached to the intake manifold. However, the intake air temperature detection device 4 may also be built into an airflow sensor (not shown) located upstream of an air cleaner (not shown), for example. The intake air temperature detection device 4 is electrically connected to the control device 1.

[0013] The atmospheric pressure detection device 6 is located in the intake pipe connected to the intake port 12 and is a device that detects atmospheric pressure P. In this embodiment, the atmospheric pressure detection device 6 is an intake pressure sensor attached to the intake pipe. However, the atmospheric pressure detection device 6 may be built into, for example, an airflow sensor located upstream of the air cleaner. The atmospheric pressure detection device 6 is electrically connected to the control device 1.

[0014] The control device 1 is a device that controls various components of the internal combustion engine E, such as the fuel injection device 2, using values ​​obtained from various sensors of the internal combustion engine E, such as the intake air temperature detection device 4 and the atmospheric pressure detection device 6. In reality, the control device 1 is an ECU (Electronic Control Unit) composed of a microcomputer including an arithmetic unit, memory, and input / output buffers. The control device 1 controls the internal combustion engine E based on maps and programs stored in memory.

[0015] Control device 1 obtains intake air temperature T from intake air temperature detection device 4. Control device 1 obtains atmospheric pressure P from atmospheric pressure detection device 6. Control device 1 obtains accelerator pedal opening Th as the amount the accelerator pedal 8 is pressed from the accelerator pedal 8. In addition, control device 1 obtains the rotational speed of the internal combustion engine E from a crank angle sensor (not shown), etc.

[0016] The control device 1 determines the required load Q to be requested from the internal combustion engine E based on the accelerator opening Th. The control device 1 acquires control quantities such as the injection quantity (fuel injection quantity) of the fuel injection device 2 and the injection timing based on the required load Q (hereinafter simply referred to as load in the specification) and the rotational speed of the internal combustion engine E. The control device 1 executes correction control for correcting the control quantities based on each of the intake air temperature T and the atmospheric pressure P.

[0017] More specifically, as shown in FIG. 2, the control device 1 stores a control quantity map 20, an intake air temperature correction quantity base map 21, an intake air temperature correction coefficient map (an example of the first map) 22, an atmospheric pressure correction quantity base map (an example of the second map) 23, and an atmospheric pressure correction coefficient map 24.

[0018] As shown in FIG. 3, the control quantity map 20 is a map that records control quantities (an example of control values corresponding to the operating state of the internal combustion engine) corresponding to the load and the rotational speed of the internal combustion engine E. In the present embodiment, the control quantity is the injection timing of the main injection. For example, the control quantity map 20 indicates a retard amount when it is positive based on top dead center, and an advance amount when it is negative. The control quantity map 20 is a map that records control quantities when the intake air temperature T is normal temperature (approximately 25°C) and the atmospheric pressure P is normal pressure (approximately 100 kPa).

[0019] The intake air temperature correction quantity base map 21 is a map that records correction quantities (an example of intake air temperature base correction quantities) serving as a basis for calculating the intake air temperature correction quantity according to the load and the rotational speed of the internal combustion engine E. The intake air temperature correction quantity base map 21 of the present embodiment is a map that records the intake air temperature correction quantity at an intake air temperature T of -30°C when the atmospheric pressure P is normal pressure. That is, the intake air temperature correction quantity base map 21 of the present embodiment records the maximum intake air temperature correction quantity assuming the state where the intake air temperature T is the lowest. The intake air temperature correction quantity recorded in the intake air temperature correction quantity base map 21 can be obtained from data of experiments etc. performed in an environment where the atmospheric pressure P is normal pressure and the intake air temperature T is -30°C in advance.

[0020] As shown in the upper part of Figure 4, the intake air temperature correction coefficient map 22 is a map that records the intake air temperature correction coefficient for correcting the intake air temperature correction amount base map 21 based on the intake air temperature T and atmospheric pressure P. The intake air temperature correction coefficient is a value that changes with the intake air temperature T and atmospheric pressure P as parameters. The intake air temperature correction coefficient map 22 records the change in the value of the intake air temperature correction coefficient when the atmospheric pressure P is within a predetermined atmospheric pressure range and the intake air temperature T is within a predetermined intake air temperature range. In this embodiment, the predetermined atmospheric pressure range is 50 kPa or more and 100 kPa or less. The intake air temperature correction coefficient map 22 records the value of the intake air temperature correction coefficient for every 10 kPa within the predetermined atmospheric pressure range. Also, in this embodiment, the predetermined intake air temperature range is -30°C or more and 25°C or less. The intake air temperature correction coefficient map 22 records the value of the intake air temperature correction coefficient for every 10°C within the predetermined intake air temperature range.

[0021] The intake air temperature T correction is performed to prevent combustion failure caused by a decrease in the intake air temperature T inside the cylinder N. The intake air temperature correction coefficient is larger as the intake air temperature T decreases, and the correction ratio, which is the ratio of the correction amount to the control amount, increases. Also, the intake air temperature correction coefficient is smaller as the atmospheric pressure P decreases, and the correction ratio decreases. Furthermore, the intake air temperature correction coefficient changes less with respect to changes in intake air temperature T as the atmospheric pressure P decreases. For example, when the atmospheric pressure P is 50kPa, the correction coefficient remains unchanged at 0.5 from -30°C to -10°C. When the atmospheric pressure P is 60kPa, the correction coefficient remains unchanged at 0.6 from -30°C to -10°C. When the atmospheric pressure P is 70kPa, the correction coefficient remains unchanged at 0.7 from -30°C to -15°C. When the atmospheric pressure P is 80kPa, the correction coefficient remains unchanged at 0.8 from -30°C to -20°C. In other words, the lower the atmospheric pressure P, the smaller the effect of changes in intake air temperature T on combustion, and therefore the smaller the change in the correction amount.

[0022] The intake air temperature correction coefficient becomes zero when the intake air temperature is above the first predetermined temperature (25°C or higher in this embodiment). In other words, when the intake air temperature T is above the first predetermined temperature, no correction is necessary. Thus, the intake air temperature correction coefficient corrects the intake pressure correction amount in one direction (increase or decrease) when the intake air temperature T is high and the atmospheric pressure P is high. As a result, the intake pressure correction amount corrects the control amount (control value) in one direction (increase or decrease) when the intake air temperature T is high and the atmospheric pressure P is high.

[0023] As shown in Figure 3, the atmospheric pressure correction amount base map 23 is a map that records the base correction amount (an example of an atmospheric pressure base correction amount) used to calculate the atmospheric pressure correction amount, according to the load and the rotational speed of the internal combustion engine E. In this embodiment, the atmospheric pressure correction amount base map 23 is a map that records the atmospheric pressure correction amount when the intake air temperature T is at room temperature and the atmospheric pressure P is 50 kPa. In other words, the atmospheric pressure correction amount base map 23 in this embodiment records the maximum atmospheric pressure correction amount, assuming the lowest possible atmospheric pressure P. The atmospheric pressure correction amount recorded in the atmospheric pressure correction amount base map 23 can be obtained from data from experiments conducted in advance under conditions where the intake air temperature T is at room temperature and the atmospheric pressure P is 50 kPa.

[0024] As shown in the lower part of Figure 4, the atmospheric pressure correction coefficient map 24 is a map that records atmospheric pressure correction coefficients for correcting the atmospheric pressure correction amount base map 23 based on intake air temperature T and atmospheric pressure P. The atmospheric pressure correction coefficient is a value that changes with intake air temperature T and atmospheric pressure P as parameters. The atmospheric pressure correction coefficient map 24 records the change in the value of the atmospheric pressure correction coefficient within a predetermined atmospheric pressure range and within a predetermined intake air temperature range. In this embodiment, similar to the intake air temperature correction coefficient, the predetermined atmospheric pressure range is 50 kPa or more and 100 kPa or less. The atmospheric pressure correction coefficient map 24 records the values ​​of the intake air temperature correction coefficient for every 10 kPa within the predetermined atmospheric pressure range. Also, in this embodiment, the predetermined intake air temperature range is -30°C or more and 25°C or less. The atmospheric pressure correction coefficient map 24 records the values ​​of the atmospheric pressure correction coefficient for every 10°C within the predetermined intake air temperature range.

[0025] The correction for atmospheric pressure P is performed to compensate for the decrease in air density and the resulting decrease in the amount of air drawn into the cylinder N as atmospheric pressure P decreases. As atmospheric pressure P decreases, air density decreases, while as intake air temperature T decreases, air density increases. Therefore, the atmospheric pressure correction coefficient is smaller and the correction rate is smaller as the intake air temperature T decreases. Conversely, the atmospheric pressure correction coefficient is larger and the correction rate is larger as the atmospheric pressure P decreases.

[0026] The atmospheric pressure correction coefficient is zero when the atmospheric pressure is above the first predetermined atmospheric pressure (100 kPa in this embodiment). In other words, when the atmospheric pressure P is above the first predetermined atmospheric pressure, no correction is necessary. That is, the atmospheric pressure correction coefficient corrects the atmospheric pressure correction amount in the opposite direction (increase or decrease) when the intake air temperature T is high and the atmospheric pressure P is high. As a result, the atmospheric pressure correction amount corrects the control amount (control value) in the opposite direction (increase or decrease) when the intake air temperature T is high and the atmospheric pressure P is high.

[0027] Comparing the intake air temperature correction coefficient map 22 and the atmospheric pressure correction coefficient map 24, the degree of change in the intake air temperature correction coefficient within a predetermined atmospheric pressure range and a predetermined intake air temperature range is smaller than the degree of change in the atmospheric pressure correction coefficient within a predetermined atmospheric pressure range and a predetermined intake air temperature range. As described above, the intake air temperature correction coefficient does not change even when the intake air temperature T changes from -30°C to -10°C when the atmospheric pressure P is 50kPa. On the other hand, the atmospheric pressure correction coefficient changes from 0.5 to 0.7 even in the same region. In other words, the change in atmospheric pressure P has a greater effect on combustion than the change in intake air temperature T. For this reason, the degree of change in the atmospheric pressure correction coefficient is larger than that of the intake air temperature correction coefficient.

[0028] As shown in Figure 2, the control device 1 calculates the intake air temperature correction amount by multiplying the intake air temperature base correction amount by the intake air temperature correction coefficient. The control device 1 calculates the atmospheric pressure correction amount by multiplying the atmospheric pressure base correction amount by the atmospheric pressure correction coefficient. The control device 1 adds the intake air temperature correction amount and the atmospheric pressure correction amount to the value of the control amount map 20 to obtain the corrected control amount 25. The control device 1 performs correction control to obtain the corrected control amount in this way.

[0029] <Second Embodiment> Next, a second embodiment of this disclosure will be described with reference to Figures 5 to 8. Note that the control device 201 in the second embodiment differs from the control device 1 in the first embodiment in its method of correcting the controlled quantity. Other aspects are the same as in the first embodiment and will therefore not be described further.

[0030] As shown in Figure 5, the control device 201 stores a control amount map 221, a first intake air temperature base correction amount map 222, a second intake air temperature base correction amount map 223, an intake air temperature correction coefficient table 224, a first atmospheric pressure base correction amount map 225, a second atmospheric pressure base correction amount map 226, an atmospheric pressure correction coefficient table 227, and a map switching coefficient map 228.

[0031] Since the control variable map 221 is the same as the control variable map 20 in the first embodiment, its description will be omitted.

[0032] The first intake air temperature base correction amount map 222 and the second intake air temperature base correction amount map 223 are maps that record the base correction amount (an example of an intake air temperature base correction amount) used to calculate the intake air temperature correction amount, according to the load and rotational speed of the internal combustion engine E. The first intake air temperature base correction amount map 222 is the same as the intake air temperature correction amount base map 21 in the first embodiment. The values ​​of the second intake air temperature base correction amount map 223 at each load and rotational speed are smaller than those of the first intake air temperature base correction amount map 222. In this embodiment, the values ​​of the second intake air temperature base correction amount map 223 are half the values ​​of the first intake air temperature base correction amount map 222. The second intake air temperature base correction amount map 223 is a map used when the intake air temperature T is low (e.g., below 0°C) and the atmospheric pressure P is low (e.g., below 80 kPa). The first intake air temperature base correction amount map 222 is a map used in environments other than low temperature and low pressure. The second intake air temperature base correction map 223 can be obtained from data previously collected under low temperature and low pressure conditions.

[0033] The intake air temperature correction coefficient table 224 records correction coefficients that are multiplied by the correction amount obtained from the first intake air temperature base correction amount map 222 or the correction amount obtained from the second intake air temperature base correction amount map 223, according to the intake air temperature T. In this embodiment, the intake air temperature correction coefficient table 224 records correction coefficients at 10°C intervals from -30°C to 25°C. The correction coefficient recorded in the intake air temperature correction coefficient table 224 is 1 at -30°C and decreases by 0.2 for every 10°C increase. On the other hand, the correction coefficient is 1 at 25°C and above.

[0034] The first atmospheric pressure base correction amount map 225 and the second atmospheric pressure base correction amount map 226 are maps that record the base correction amount (an example of an atmospheric pressure base correction amount) used to calculate the atmospheric pressure correction amount, according to the load and rotational speed of the internal combustion engine E. The first atmospheric pressure base correction amount map 225 is the same as the atmospheric pressure correction amount base map 23 in the first embodiment. The values ​​of the second atmospheric pressure base correction amount map 226 for each load and rotational speed are smaller than those of the first atmospheric pressure base correction amount map 225. In this embodiment, the values ​​of the second atmospheric pressure base correction amount map 226 are half the values ​​of the first atmospheric pressure base correction amount map 225. The second atmospheric pressure base correction amount map 226 is a map used when the atmospheric pressure P is low (e.g., below 0°C) and the atmospheric pressure is low (e.g., below 80 kPa). The first atmospheric pressure base correction amount map 225 is a map used in environments other than low temperature and low pressure. The second atmospheric pressure base correction map 226 can be obtained from data previously collected through experiments conducted under low-temperature and low-pressure conditions.

[0035] The atmospheric pressure correction coefficient table 227 records correction coefficients that are multiplied by the correction amount obtained from the first atmospheric pressure base correction amount map 225 or the correction amount obtained from the second atmospheric pressure base correction amount map 226, according to the atmospheric pressure P. In this embodiment, the atmospheric pressure correction coefficient table 227 records correction coefficients at 10kPa intervals from 50kPa to 100kPa. At 50kPa, the correction coefficient is 1, and the coefficient decreases by 0.2 for every 10kPa increase. On the other hand, at 100kPa, the correction coefficient is 0.

[0036] Map switching coefficient map 228 is a map that records map switching coefficients for performing the switching between the first intake air temperature-based correction amount map 222 and the second intake air temperature-based correction amount map 223 based on the intake air temperature T and atmospheric pressure P. Furthermore, map switching coefficient map 228 is a map that records map switching coefficients for performing the switching between the first atmospheric pressure-based correction amount map 225 and the second atmospheric pressure-based correction amount map 226 based on the intake air temperature T and atmospheric pressure P.

[0037] The map switching coefficient is a value that changes with intake air temperature T and atmospheric pressure P as parameters. In this embodiment, the map switching coefficient is 1 and 0. When the map switching coefficient is less than 1, the control device 201 corrects the controlled amount using the first intake air temperature-based correction amount map 222 and the first atmospheric pressure-based correction amount map 225. When the map switching coefficient is 1 or greater, the control device 201 corrects the controlled amount using the second intake air temperature-based correction amount map 223 and the second atmospheric pressure-based correction amount map 226.

[0038] In this embodiment, the map switching coefficient map 228 records the change in the value of the map switching coefficient within a predetermined atmospheric pressure range and a predetermined intake temperature range. The predetermined atmospheric pressure range is 50 kPa or more and 100 kPa or less. The predetermined intake temperature range is -30°C or more and 25°C or less. The map switching coefficient map 228 records the values ​​of the map switching coefficient for every 10°C and every 10 kPa within the predetermined atmospheric pressure range. The map switching coefficient is recorded as a value less than 1 (0 in this embodiment) above the second predetermined intake temperature and above the second predetermined atmospheric pressure, and as a value of 1 or more (1 in this embodiment) below the second predetermined intake temperature and below the second predetermined atmospheric pressure. In this embodiment, the second predetermined intake temperature is 0°C and the second predetermined atmospheric pressure is 80 kPa. In this embodiment, the map switching coefficient map 228 is set so that the lower the intake temperature T, the greater the value will be, even at large atmospheric pressures P. For example, when the intake air temperature T is -10°C, the value is 1 when the atmospheric pressure P is 50kPa or less, but when the intake air temperature T is -30°C, the value is set to remain 1 up to atmospheric pressure P of 70kPa or less.

[0039] As shown in Figure 5, the control device 201 acquires the intake air temperature T and atmospheric pressure P. When the intake air temperature T is less than the second predetermined intake air temperature and the atmospheric pressure P is less than the second predetermined atmospheric pressure, the control device 201 acquires a value of 1 or more (1 in this embodiment) for the map switching coefficient. Since the map switching coefficient is 1 or more, the control device 201 acquires the correction amount for each load and each rotation from the second intake air temperature base correction amount map 223 and the second atmospheric pressure base correction amount map 226. The control device 201 refers to the intake air temperature correction coefficient table 224 and acquires the coefficient corresponding to the acquired intake air temperature T. The control device 201 calculates the intake air temperature correction amount by multiplying the acquired coefficient by the correction amount value acquired from the second intake air temperature base correction amount map 223. The control device 201 refers to the atmospheric pressure correction coefficient table 227 and acquires the coefficient corresponding to the acquired atmospheric pressure P. The control device 201 calculates the atmospheric pressure correction amount by multiplying the acquired coefficient by the correction amount value acquired from the second atmospheric pressure base correction amount map 226. The control device 201 adds the sum of the intake air temperature correction amount and the atmospheric pressure correction amount to the value of the control amount map 221 to obtain the corrected control amount 229. The control device 201 performs correction control to obtain the corrected control amount 229 in this manner.

[0040] On the other hand, when the intake air temperature T is equal to or greater than the second predetermined intake air temperature, or when the atmospheric pressure P is equal to or greater than the second predetermined atmospheric pressure, the control device 201 obtains a value of less than 1 (0 in this embodiment) for the map switching coefficient. In this case, since the map switching coefficient is less than 1, the control device 201 obtains the correction amount for each load and each rotation from the first intake air temperature-based correction amount map 222 and the first atmospheric pressure-based correction amount map 225. The subsequent calculations performed by the control device 201 are the same as when the map switching coefficient is 1 or greater. By using the first intake air temperature-based correction amount map 222, the second intake air temperature-based correction amount map 223, the intake air temperature correction coefficient table 224, and the map switching coefficient map 228, the intake pressure correction amount corrects the control amount (control value) in one direction (increase or decrease) when the intake air temperature T is high and the atmospheric pressure P is high. On the other hand, by using the first atmospheric pressure base correction amount map 225, the second atmospheric pressure base correction amount map 226, the atmospheric pressure correction coefficient table 227, and the map switching coefficient map 228, the atmospheric pressure correction amount corrects the control amount (control value) in the opposite direction (increase or decrease) when the intake air temperature T is high and the atmospheric pressure P is high.

[0041] As described above, according to the control device 1 of the first embodiment and the control device 201 of the second embodiment of this disclosure, the control device 1 and the control device 201 acquire the intake air temperature correction amount and the atmospheric pressure correction amount separately, respectively. The control device 1 calculates the intake air temperature correction amount using an intake air temperature correction coefficient map with atmospheric pressure P as a parameter, so the intake air temperature correction amount becomes a correction amount corresponding to the change in atmospheric pressure P. The control device 201 calculates the intake air temperature correction amount using a map switching coefficient map with atmospheric pressure P as a parameter, so the intake air temperature correction amount becomes a correction amount corresponding to the change in atmospheric pressure P.

[0042] Furthermore, since control device 1 calculates the atmospheric pressure correction amount using an atmospheric pressure correction coefficient map with intake air temperature T as a parameter, the atmospheric pressure correction amount becomes a correction amount that corresponds to the change in intake air temperature T. Since control device 201 calculates the intake air temperature correction amount using a map switching coefficient map with intake air temperature T as a parameter, the atmospheric pressure correction amount becomes a correction amount that corresponds to the change in atmospheric pressure P.

[0043] As a result, we can provide an internal combustion engine control device 1,201 that can prevent excessive correction while separately performing corrections based on intake air temperature T and atmospheric pressure P.

[0044] <Other Embodiments> Although embodiments of the present disclosure have been described above, the present disclosure is not limited to the embodiments described above, and various modifications are possible without departing from the spirit of the invention. In particular, the various modifications described herein can be combined as needed.

[0045] In the first embodiment described above, the intake air temperature correction coefficient map 22 was explained using an example in which intake air temperature correction coefficient values ​​are recorded at 10°C intervals within the range of intake air temperature T from -30°C to 25°C and atmospheric pressure P from 50kPa to 100kPa, but the disclosure is not limited thereto. The ranges of intake air temperature T and atmospheric pressure P recorded in the intake air temperature correction coefficient map 22 may be changed as appropriate.

[0046] In the first embodiment described above, the atmospheric pressure correction coefficient map 24 was explained using an example in which intake air temperature correction coefficient values ​​are recorded at 10°C intervals within the range of intake air temperature T from -30°C to 25°C and at 10kPa intervals within the range of atmospheric pressure P from 50kPa to 100kPa. However, the disclosure is not limited thereto. The ranges of intake air temperature T and atmospheric pressure P recorded in the atmospheric pressure correction coefficient map 24 may be changed as appropriate.

[0047] In the second embodiment described above, the map switching coefficient map 228 was explained using an example in which intake air temperature correction coefficient values ​​are recorded at 10°C intervals within the range of intake air temperature T from -30°C to 25°C and at 10kPa intervals within the range of atmospheric pressure P from 50kPa to 100kPa. However, the disclosure is not limited thereto. The ranges of intake air temperature T and atmospheric pressure P recorded in the map switching coefficient map 228 may be changed as appropriate.

[0048] In the first and second embodiments described above, the injection timing of the main injection was used as an example of a control value corresponding to the operating state of the internal combustion engine E, but this disclosure is not limited thereto. The control value may be, for example, the injection amount. In this case, the control devices 1 and 201 may store maps corresponding to the injection amount. Furthermore, when the present invention is applied to a gasoline engine, the control value may be, for example, the intake air volume (throttle valve opening, etc.).

[0049] Furthermore, in the first and second embodiments described above, the intake air temperature correction coefficient is integrated into the intake air temperature correction amount, and the atmospheric pressure correction coefficient is integrated into the atmospheric pressure correction amount. However, the method of correction is not limited to integrating the intake air temperature correction coefficient and atmospheric pressure correction coefficient into the intake air temperature correction amount and atmospheric pressure correction amount, but can be performed by addition, subtraction, division, etc. The correction coefficients may be changed according to the method of correction.

[0050] Furthermore, in the first and second embodiments described above, the map used for correction control was changed stepwise (discontinuously) according to the intake air temperature T and atmospheric pressure P. However, it may also be changed continuously according to the intake air temperature T and atmospheric pressure P, or it may be changed stepwise in some regions and continuously in other regions according to the intake air temperature T and atmospheric pressure P. [Explanation of Symbols]

[0051] 1,201: Control device 2: Fuel injection system, 4: Intake air temperature sensor, 6: Atmospheric pressure sensor, 8: Accelerator pedal 20,221: Controlled variable map 21: Intake air temperature correction amount base map, 22: Intake air temperature correction coefficient map 23: Atmospheric pressure correction amount base map, 24: Atmospheric pressure correction coefficient map 26: Corrected control amount 222: Map of the first intake air temperature-based correction amount, 223: Map of the second intake air temperature-based correction amount 224: Intake Air Temperature Correction Coefficient Table 225: Map of the first atmospheric pressure-based correction amount, 226: Map of the second atmospheric pressure-based correction amount 227: Atmospheric Pressure Correction Coefficient Table 228: Map switching coefficient map 229: Corrected control amount E: Internal combustion engine, N: cylinder P: atmospheric pressure, T: intake temperature

Claims

1. A control device for an internal combustion engine capable of obtaining intake air temperature and atmospheric pressure, Determine the control values ​​that control the operating state of the internal combustion engine. An intake air temperature correction amount, which is the correction amount for the control value based on the intake air temperature, is obtained. An atmospheric pressure correction amount, which is the correction amount for the control value based on the aforementioned atmospheric pressure, is obtained. Correction control is performed to correct the control value using the intake air temperature correction amount and the atmospheric pressure correction amount. The intake air temperature correction amount is calculated using at least the intake air temperature and the atmospheric pressure as parameters. The atmospheric pressure correction amount is calculated using at least the intake air temperature and the atmospheric pressure as parameters. The intake air temperature correction amount corrects the control value in either an increasing or decreasing direction when the intake air temperature is high and the atmospheric pressure is high. The atmospheric pressure correction amount corrects the control value in the opposite direction (increase or decrease) when the intake air temperature is high and the atmospheric pressure is high. Control device for internal combustion engines.

2. The intake air temperature correction amount is calculated using at least the atmospheric pressure and the intake air temperature as parameters. The atmospheric pressure correction amount is calculated using at least the atmospheric pressure and the intake air temperature as parameters. A control device for an internal combustion engine according to claim 1.

3. The intake air temperature correction amount is calculated by multiplying the intake air temperature base correction amount by the intake air temperature correction coefficient. The aforementioned atmospheric pressure correction amount is calculated by multiplying the atmospheric pressure base correction amount by the atmospheric pressure correction coefficient. The intake air temperature correction coefficient is a value that changes with respect to at least the atmospheric pressure and the intake air temperature as parameters. The atmospheric pressure correction coefficient is a value that changes with respect to at least the atmospheric pressure and the intake air temperature. A control device for an internal combustion engine according to claim 1.

4. The intake air temperature correction coefficient is larger the lower the intake air temperature and smaller the lower the atmospheric pressure. The aforementioned atmospheric pressure correction coefficient is smaller as the intake air temperature decreases, and larger as the atmospheric pressure decreases. The control device for an internal combustion engine according to claim 3.

5. The intake air temperature correction coefficient is determined by a first map using the intake air temperature and atmospheric pressure. The aforementioned atmospheric pressure correction coefficient is determined by a second map using the intake air temperature and the atmospheric pressure. The first map has a value of zero when the intake air temperature is above the first predetermined temperature. The second map shows a value of zero when the atmospheric pressure is above the first predetermined atmospheric pressure. The control device for an internal combustion engine according to claim 3.

6. The first map records the change in the value of the intake air temperature correction coefficient when the atmospheric pressure is within a predetermined atmospheric pressure range and the intake air temperature is within a predetermined intake air temperature range. The second map records the change in the value of the atmospheric pressure correction coefficient within the predetermined atmospheric pressure range and the predetermined intake temperature range. The degree of change in the value of the intake air temperature correction coefficient within the predetermined atmospheric pressure range and the predetermined intake air temperature range is smaller than the degree of change in the atmospheric pressure correction coefficient within the predetermined atmospheric pressure range and the predetermined intake air temperature range. The control device for an internal combustion engine according to claim 5.

7. The intake air temperature correction amount is calculated by multiplying the intake air temperature base correction amount by the intake air temperature correction coefficient. The aforementioned atmospheric pressure correction amount is calculated by multiplying the atmospheric pressure base correction amount by the atmospheric pressure correction coefficient. The intake air temperature base correction amount is a value that changes with at least the atmospheric pressure and the intake air temperature as parameters. The atmospheric pressure-based correction amount is a value that varies with at least the atmospheric pressure and the intake air temperature as parameters. A control device for an internal combustion engine according to claim 1.

8. The intake air temperature base correction amount comprises a first intake air temperature base correction amount and a second intake air temperature base correction amount. The atmospheric pressure-based correction amount comprises a first atmospheric pressure-based correction amount and a second atmospheric pressure-based correction amount. The second intake air temperature base correction amount is smaller than the first intake air temperature base correction amount. The second atmospheric pressure-based correction amount is smaller than the first atmospheric pressure-based correction amount. When the intake air temperature is equal to or greater than the second predetermined intake air temperature, or when the atmospheric pressure is equal to or greater than the second predetermined atmospheric pressure, the first intake air temperature-based correction amount and the first atmospheric pressure-based correction amount are used. When the intake air temperature is less than the second predetermined intake air temperature and the atmospheric pressure is less than the second predetermined atmospheric pressure, the second intake air temperature-based correction amount and the second atmospheric pressure-based correction amount are used. The control device for an internal combustion engine according to claim 7.

9. The correction control adds the sum of the intake air temperature correction amount and the atmospheric pressure correction amount to the control value. A control device for an internal combustion engine according to any one of claims 1 to 8.

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