WO2018061468A1

WO2018061468A1 - Internal combustion engine control device

Info

Publication number: WO2018061468A1
Application number: PCT/JP2017/027927
Authority: WO
Inventors: 将司小川; 佐々木　亮
Original assignee: 株式会社ケーヒン
Priority date: 2016-09-27
Filing date: 2017-08-01
Publication date: 2018-04-05
Also published as: JP6692269B2; JP2018053743A

Abstract

Provided is an internal combustion engine control device (1) that controls the operating state of an internal combustion engine mounted in an internal combustion engine mounting body, the control device (1): acquiring the ambient temperature of the internal combustion engine; acquiring an injector temperature, which is the temperature of an injector (7) of the internal combustion engine, from a resistance value of a coil (7a) of the injector (7); calculating an intake temperature increase amount of the internal combustion engine from the ambient temperature and the injector temperature; and calculating an intake temperature of the internal combustion engine by adding the intake temperature increase amount to the ambient temperature.

Description

Internal combustion engine control device

The present invention relates to an internal combustion engine control device applied to a general-purpose machine such as a generator or a vehicle such as a motorcycle.

In recent years, in general-purpose machines such as generators and vehicles such as small motorcycles, it has become difficult to meet exhaust gas regulations that will become stricter in the future with carburetor systems, so a fuel injection system has been adopted to reduce exhaust gas. Is promoted. However, since the sales price of general-purpose machines such as generators and vehicles such as small motorcycles is lower than the sales prices of vehicles such as large motorcycles and four-wheeled vehicles, such a sales price was considered. In this case, it is difficult to adopt a fuel injection system that is more expensive than a carburetor system as it is for a general-purpose machine such as a generator or a vehicle such as a small motorcycle. For this reason, in general-purpose machines such as generators and vehicles such as small motorcycles, cost reduction is required for parts related to the fuel injection system, particularly sensors.

Here, for example, an intake air temperature sensor in a fuel injection system is generally used for calculating the air density taken into the internal combustion engine. Specifically, the fuel injection system calculates the intake air temperature of the internal combustion engine based on the output of the intake air temperature sensor, detects the air density taken into the internal combustion engine based on the calculated intake air temperature of the internal combustion engine, Ignition timing and fuel injection are controlled. For this reason, when adopting a fuel injection system, it is necessary to attach an intake air temperature sensor to the internal combustion engine. Furthermore, when installing the intake air temperature sensor in the internal combustion engine, it is necessary to install wires and couplers for wiring, and it is necessary to process the part of the internal combustion engine where the intake air temperature sensor is installed. As a result, the ratio of the cost of the fuel injection system to the sales price is higher than that of the carburetor system. For this reason, in an internal combustion engine control apparatus that controls a fuel injection system in a vehicle such as a general-purpose machine such as a generator or a small motorcycle, it is required to omit an intake air temperature sensor from the fuel injection system for the purpose of cost reduction. ing.

Under such circumstances, Patent Document 1 relates to an intake air temperature estimation device for an internal combustion engine that estimates the intake air temperature of the internal combustion engine 1 in order to set the fuel injection amount, and relates to the outside air temperature and the heat from the engine room to the intake system of the engine. A configuration is disclosed in which the amount of transmission and the amount of heat conduction from the engine room to the intake system of the engine are estimated, and the intake temperature of the internal combustion engine 1 is estimated based on these estimation results. The outside air temperature is estimated using the cooling fan ON / OFF time, the engine heat generation amount, and the vehicle speed. The amount of heat transfer from the engine room to the engine intake system is estimated using the amount of heat generated by the engine and the amount of heat released from the engine room. Furthermore, the amount of heat conduction from the engine room to the engine intake system is estimated using the amount of heat generated by the engine and the temperature of the engine.

JP-A-9-189256

However, according to the study of the present inventor, when estimating the intake air temperature of the internal combustion engine with the configuration of Patent Document 1, it is difficult to actually mount the intake air on the vehicle because the estimation method is complicated. The storage capacity of the storage device such as the ROM of the control device increases, resulting in an increase in cost. In addition, when estimating the amount of heat transfer from the engine room to the engine intake system and the amount of heat conduction from the engine room to the engine intake system as in the configuration of Patent Document 1, a motorcycle without the concept of an engine room is used. Is difficult to apply. In addition, when estimating the outside air temperature using the vehicle speed or the ON / OFF time of the cooling fan as in the configuration of Patent Document 1, some inexpensive motorcycles or the like are not equipped with a vehicle speed sensor and a cooling fan. It is difficult to apply because it exists. Furthermore, the outside air temperature used for estimating the intake air temperature in the configuration of Patent Document 1, the heat transfer amount from the engine room to the engine intake system, and the heat transfer amount from the engine room to the engine intake system are: Since it is an estimated value, there is a possibility that the intake air temperature cannot be estimated accurately.

The present invention has been made through the above-described studies, and can be practically mounted on an actual vehicle including a two-wheeled vehicle, and has a simple configuration and can reduce the storage capacity of a storage device such as a ROM of a control device. Therefore, it is an object of the present invention to provide an internal combustion engine control apparatus that can reduce the overall cost and can calculate the intake air temperature of the internal combustion engine with sufficient accuracy for practical use.

In order to achieve the above object, according to the first aspect of the present invention, in the internal combustion engine control device including a control unit that controls an operating state of the internal combustion engine mounted on the internal combustion engine mounting body, the control unit includes: An ambient temperature of the internal combustion engine is acquired, an injector temperature that is the temperature of the injector is acquired from a resistance value of the injector of the internal combustion engine, and an intake air temperature increase amount of the internal combustion engine is calculated from the ambient temperature and the injector temperature The internal combustion engine control device calculates the intake air temperature of the internal combustion engine by adding the intake air temperature rise amount to the ambient temperature.

According to the present invention, in addition to the first aspect, the control unit uses the correlation characteristic that defines a relationship between a difference temperature between the injector temperature and the ambient temperature and the intake air temperature rise amount, to use the intake air temperature. The second aspect is to calculate the amount of increase.

In the present invention, in addition to the first or second aspect, the control unit calculates an injection amount correction value of the injector from a fuel injection time per unit time of the internal combustion engine, and calculates the intake air temperature increase amount Correction with the injection amount correction value is a third aspect.

In addition to the third aspect, the present invention has a fourth aspect in which the control unit performs a filtering process on the calculated intake air temperature.

In addition to any of the first to fourth aspects, the present invention provides a first temperature sensor disposed in a casing of the internal combustion engine control device, and a position spaced from the first temperature sensor in the casing. A second temperature sensor disposed on the first temperature sensor, wherein the control unit determines a detected temperature of one of the first temperature sensor and the second temperature sensor of the first temperature sensor and the second temperature sensor. It is a fifth aspect to calculate the ambient temperature by correcting with the other detected temperature.

In the internal combustion engine control apparatus according to the first aspect of the present invention, the internal combustion engine control apparatus includes a control unit that controls the operating state of the internal combustion engine mounted on the internal combustion engine mounting body. Obtain the ambient temperature, obtain the injector temperature, which is the injector temperature, from the resistance value of the injector of the internal combustion engine, calculate the intake air temperature rise amount of the internal combustion engine from the ambient temperature and injector temperature, and add the intake air temperature rise amount to the ambient temperature Since the intake air temperature of the internal combustion engine is calculated by adding, it can be practically installed in an actual vehicle including a two-wheeled vehicle, and has a simple configuration and the storage capacity of a storage device such as a ROM of a control device. Since it can be reduced, the overall cost can be suppressed, and the intake air temperature of the internal combustion engine can be calculated with practically sufficient accuracy.

Further, according to the internal combustion engine control apparatus according to the second aspect of the present invention, the control unit uses the correlation characteristic that defines the relationship between the difference temperature between the injector temperature and the ambient temperature and the intake air temperature rise amount. Since the intake air temperature rise is calculated, the intake air temperature rise that has a correlation with the difference between the injector temperature and the engine ambient temperature is correlated with the correlation characteristic that defines the relationship between the differential temperature and the intake air temperature rise. Can be used to calculate.

Further, according to the internal combustion engine control apparatus of the third aspect of the present invention, the control unit calculates the injector injection amount correction value from the fuel injection amount per unit time of the internal combustion engine, and injects the intake air temperature increase amount. Since the correction is performed by the amount correction value, the intake air temperature can be calculated with high accuracy by calculating the intake air temperature in consideration of the decrease in the intake air temperature due to the traveling wind according to the vehicle speed of the vehicle.

Further, according to the internal combustion engine control apparatus according to the fourth aspect of the present invention, the control unit filters the calculated intake air temperature, so that the injector temperature increase characteristic and the intake air temperature increase characteristic coincide with each other. By doing so, the intake air temperature can be accurately calculated.

In addition, according to the internal combustion engine control apparatus of the fifth aspect of the present invention, the first temperature sensor disposed in the casing of the internal combustion engine control apparatus and the position separated from the first temperature sensor in the casing. A second temperature sensor provided, and the control unit corrects the detected temperature of one of the first temperature sensor and the second temperature sensor with the detected temperature of the other of the first temperature sensor and the second temperature sensor. Therefore, the atmospheric temperature can be calculated with high accuracy.

FIG. 1A is a schematic diagram illustrating a configuration of an internal combustion engine control device according to a first embodiment of the present invention. It is a schematic diagram which shows the structure of the injector in FIG. 1A. FIG. 2 is a flowchart showing the flow of the intake air temperature calculation process of the internal combustion engine controller according to the present embodiment. FIG. 3A is a diagram showing an intake air temperature rise amount table referred to by the internal combustion engine control apparatus in the present embodiment. FIG. 3B is a diagram showing, as an example, changes in intake air temperature and the like calculated by the internal combustion engine control apparatus according to the present embodiment. FIG. 4 is a schematic diagram showing the configuration of the internal combustion engine control apparatus according to the second embodiment of the present invention.

Hereinafter, an internal combustion engine control apparatus according to each embodiment of the present invention will be described in detail with reference to the drawings as appropriate.

(First embodiment)
<Configuration of internal combustion engine control device>
First, with reference to FIG. 1A and FIG. 1B, the structure of the internal combustion engine control apparatus in the 1st Embodiment of this invention is demonstrated. The internal combustion engine control device in the present embodiment is typically suitably mounted on an internal combustion engine mounting body such as a general-purpose machine such as a generator or a vehicle such as a motorcycle. The internal combustion engine control device will be described as being mounted on a vehicle such as a motorcycle.

FIG. 1A is a schematic diagram showing a configuration of an internal combustion engine control apparatus according to the present embodiment, and FIG. 1B is a schematic diagram showing a configuration of an injector in FIG. 1A.

As shown in FIGS. 1A and 1B, the internal combustion engine control device 1 according to the present embodiment is based on the temperature of functional parts of an engine that is an internal combustion engine such as a gasoline engine mounted on a vehicle not shown. The electronic control unit (Electronic Control Unit: ECU) 10 is provided.

The ECU 10 operates using the electric power from the battery B mounted on the vehicle, and the waveform shaping circuit 11, the thermistor element 12, the A / D converter 13, the ignition circuit 14, the drive circuit 15, and the resistance value detection. A circuit 16, an EEPROM (Electrically Erasable Programmable Read-Only Memory) 17, a ROM (Read-Only Memory) 18, a RAM (Random Access Memory) 19, a timer 20, and a central processing unit (Central CPU 21) Yes. Each component of the ECU 10 is accommodated in a casing 10a of the ECU 10. Also, typically, the ECU 10 and the engine are in contact with the outside air, and the ECU 10 is arranged away from the engine 10 so as not to be affected by the radiant heat of the engine and the heat transfer from the engine. Is.

The waveform shaping circuit 11 shapes a crank pulse signal corresponding to the rotation angle of the crankshaft 3 of the engine output from the crank angle sensor 2 to generate a digital pulse signal. The waveform shaping circuit 11 outputs the digital pulse signal thus generated to the CPU 21.

The thermistor element 12 is separated from the ignition circuit 14 which is typically a heat generating element in the casing 10a of the ECU 10, and is located on the atmosphere side of the ECU 10 (for example, a casing whose distance to the casing 10a is about several millimeters). A chip thermistor disposed at a position close to the body 10a, and detects an ambient temperature (outside temperature) that is an ambient temperature outside the casing 10a of the ECU 10. Specifically, the thermistor element 12 exhibits an electrical resistance value corresponding to the ambient temperature, and outputs an electrical signal indicating a voltage corresponding to the electrical resistance value to the A / D converter 13.

Note that the thermistor element 12 may be replaced with another temperature sensor such as a thermocouple as long as it can output such an electrical signal. The temperature detected by the thermistor element 12 is equal to the atmospheric temperature (outside air temperature) that is the ambient air temperature around the engine. Further, since the thermistor element 12 is arranged on a circuit board (not shown) like the other components of the ECU 10, it is not necessary to provide a separate wiring and electrically connect the thermistor element 12 via this.

The A / D converter 13 is an electric signal indicating the opening degree of the throttle valve of the engine output from the throttle opening degree sensor 4 and an electric signal indicating the oxygen concentration in the atmosphere sucked into the engine output from the oxygen sensor 5. , And the electrical signal indicating the ambient temperature output from the thermistor element 12 is converted from an analog form to a digital form. The A / D converter 13 outputs these electrical signals thus converted into digital form to the CPU 21.

The ignition circuit 14 includes a switching element such as a transistor that is controlled to be turned on / off in accordance with a control signal from the CPU 21. When the switching element is turned on / off, the fuel in the engine is passed through a spark plug (not shown). And the operation of the ignition coil 6 for generating a secondary voltage for igniting the air-fuel mixture. The ignition circuit 14 is typically a driver IC (Integrated Circuit) that is a semiconductor element, and is a component that generates the largest amount of heat in the housing 10a.

The drive circuit 15 includes a switching element such as a transistor that is controlled to be turned on / off according to a control signal from the CPU 21, and the switching element is turned on / off to energize the coil 7a of the injector 7 that supplies fuel to the engine. / Switch the de-energized state. Here, the injector 7 is attached to an intake pipe or a cylinder head (not shown) of the engine, and heat generated from the engine is transferred. Further, as shown in FIG. 1B in particular, the equivalent circuit 7b of the coil 7a of the injector 7 is represented by a series circuit including an inductance component L and an electric resistance component R. The coil 7a is a component for electrically driving the solenoid 7c of the injector 7, and the fuel is ejected from the injector 7 when the solenoid 7c operates in the energized state of the coil 7a.

The resistance value detection circuit 16 measures an electrical resistance value (resistance value) that is a physical quantity that varies depending on the electrical resistance component of the coil 7a of the injector 7, and sends an electrical signal indicating the measured resistance value to the CPU 21. Output.

The EEPROM 17 stores data relating to various learning values such as a fuel injection amount learning value and a throttle reference position learning value. Note that the EEPROM 17 may be replaced with another storage medium such as a data flash as long as it can store data relating to such various learning values.

The ROM 18 is configured by a non-volatile storage device, and includes a control program for an intake air temperature calculation process described later, data related to an intake air temperature increase amount table used in the intake air temperature calculation process, data related to an injector injection amount subtraction value calculation table, and an injector temperature. Various control data such as data relating to the table are stored.

The RAM 19 is composed of a volatile storage device and functions as a working area for the CPU 21.

The timer 20 performs a time measurement process according to a control signal from the CPU 21.

CPU21 as a control part controls operation | movement of ECU10 whole. In the present embodiment, the CPU 21 executes the control program for the intake air temperature calculation process stored in the ROM 18, thereby obtaining the intake air temperature rise amount table and the injector injection amount subtraction value calculation table stored in the ROM 18. The intake air temperature is calculated while referring to it. The CPU 21 controls the operating state of the engine by controlling the ignition circuit 14 and the drive circuit 15 based on the intake air temperature thus calculated and the engine temperature separately detected.

The internal combustion engine control device 1 having such a configuration calculates the intake air temperature by executing the following intake air temperature calculation process. Hereinafter, the intake air temperature calculation process in the present embodiment will be described more specifically.

<Intake air temperature calculation processing>
With reference to FIG. 2, FIG. 3A and FIG. 3B, the specific flow of the intake air temperature calculation processing in this embodiment will be described in detail.

FIG. 2 is a flowchart showing the flow of the intake air temperature calculation process of the internal combustion engine controller according to the present embodiment. FIG. 3A is a diagram showing an intake air temperature rise amount table referred to by the internal combustion engine control device in the present embodiment, and FIG. 3B shows an example of changes in the intake air temperature and the like calculated by the internal combustion engine control device in the present embodiment. FIG.

Here, the temperature of the intake air to the internal combustion engine is substantially equal to the outside air temperature at the outside air inlet, but rises by receiving heat from the intake passage. There is a correlation between the amount of increase in intake air temperature and the difference between the temperature of the intake path and the outside air temperature. Therefore, the intake air temperature rise amount can be obtained by calculation using the temperature of the intake passage and the ambient temperature. Further, since the temperature of the suction path can be represented by the injector temperature Tinj, it can be regarded as the same as the injector temperature Tinj.

Specifically, the flowchart shown in FIG. 2 starts when the ignition switch of the vehicle is switched from the off state to the on state and the CPU 21 operates, and the intake air temperature calculation process proceeds to step S1. The intake air temperature calculation process is repeatedly executed at predetermined control cycles while the CPU 21 is operating with the ignition switch of the vehicle turned on.

In step S1, the CPU 21 detects the engine ambient temperature (thermistor temperature Tthr) via the thermistor element 12 and the A / D converter 13. Thereby, the process of step S1 is completed and the intake air temperature calculation process proceeds to the process of step S2.

In step S2, the CPU 21 detects the resistance value (INJ resistance value) of the injector 7 through the resistance value detection circuit 16. Here, since the resistance value of the injector 7 has a characteristic of increasing in proportion to the temperature, the injector temperature Tinj can be obtained using this characteristic. Then, the CPU 21 obtains the value of the injector temperature Tinj corresponding to the detected resistance value of the injector 7 from the injector temperature table indicating the relationship between the resistance value of the injector 7 and the value of the injector temperature Tinj stored in advance in the ROM 18. calculate. Thereby, the process of step S2 is completed, and the intake air temperature calculation process proceeds to the process of step S3.

In the process of step S3, the CPU 21 searches the intake air temperature rise amount table shown in FIG. 3A stored in advance in the ROM 18, and is detected in the process of step S1 and the injector temperature Tinj calculated in the process of step S2. The value of the intake air temperature increase ΔTA corresponding to the difference temperature between the engine ambient temperature Tthr and the engine temperature Tinj-engine ambient temperature Tthr is obtained. Here, according to the study by the present inventor, the intake air temperature and the differential temperature (Tinj−Tthr) increase with the increase of the injector temperature Tinj, and the differential temperature (Tinj−Tthr) and the intake air temperature increase amount ΔTA are increased. Since there is a strong correlation, referring to the data of the intake air temperature rise table shown in FIG. 3A as a correlation characteristic curve that defines the relationship between the differential temperature (Tinj−Tthr) and the intake air temperature rise ΔTA, the differential temperature ( An intake air temperature rise amount ΔTA corresponding to (Tinj−Tthr) can be obtained. Thereby, the process of step S3 is completed, and the intake air temperature calculation process proceeds to the process of step S4.

In the process of step S4, the CPU 21 searches the injector injection amount subtraction value calculation table that defines the relationship between the fuel injection amount per predetermined unit time and the injector injection amount subtraction value stored in advance in the ROM 18 to obtain a predetermined value. An injector injection amount subtraction value (injection amount correction value) corresponding to the fuel injection amount per unit time is obtained. Here, the fuel injection amount may be obtained by converting the fuel injection time of the injector 7 into the fuel injection amount, or the fuel injection time of the injector 7 may be used as the fuel injection amount as it is. Then, the CPU 21 calculates a corrected intake air temperature increase amount ΔTB by subtracting the injector injection amount subtraction value from the intake air temperature increase amount ΔTA calculated in step S3. When the fuel injection amount (fuel injection time) increases when the internal combustion engine is at a high load or the like, the vehicle speed increases and the traveling wind received by the vehicle increases, so the intake path through which the intake air passes is cooled, The actual intake air temperature rise from the ambient temperature is lower than the intake air temperature rise ΔTA calculated from the injector temperature Tinj. Therefore, the CPU 21 subtracts the injector injection amount subtraction value, which is the intake air temperature cooled and lowered by the traveling wind, from the intake air temperature increase amount ΔTA, thereby correcting the actual intake air temperature from the ambient temperature. Determine the intake air temperature rise amount ΔTB. Thereby, the process of step S4 is completed, and the intake air temperature calculation process proceeds to the process of step S5.

In the process of step S5, the CPU 21 calculates a value obtained by adding the corrected intake air temperature increase ΔTB calculated in the process of step S4 to the engine ambient temperature Tthr detected in the process of step S1 as the intake air temperature TA. Thereby, the process of step S5 is completed, and the intake air temperature calculation process proceeds to the process of step S6.

In the process of step S6, the CPU 21 calculates the filtered intake air temperature by delaying the change (temporal change) of the intake air temperature by filtering the intake air temperature TA calculated in the process of step S5. Such filtering processing is typically processing for obtaining a load average or moving average of the intake air temperature TA. Thereby, the process in step S6 is completed, and the current series of intake air temperature calculation processes ends.

Then, the CPU 21 controls the ignition circuit 14 based on the intake air temperature estimated by executing the intake air temperature calculation process described above, and ignites the fuel / air mixture in the engine via a spark plug (not shown). . Further, the CPU 21 controls the drive circuit 15 based on the intake air temperature estimated by executing the intake air temperature calculation process described above, and causes the injector 7 to supply fuel to the engine. Note that the intake air temperature used by the CPU 21 here is an increase in the intake air temperature calculated in the process of step S3 to the ambient temperature Tthr of the engine detected in the process of step S1, depending on the accuracy of the required intake air temperature. A value obtained by adding the amount ΔTA, a value obtained by adding the corrected intake air temperature increase ΔTB calculated in the process of step S4 to the engine ambient temperature Tthr detected in the process of step S1, or these values are processed in the process of step S6. It is possible to use a filtered value as shown in FIG.

Thus, since the intake air temperature sensor can be omitted from the internal combustion engine controller 1, the ignition timing and fuel injection can be controlled by an inexpensive system.

Further, by controlling the ignition timing and fuel injection using the fuel injection system, it is possible to reduce the exhaust gas as compared with the carburetor system.

Furthermore, at the development stage, when shifting from the carburetor system to the fuel injection system, development items such as the design of the mounting positions of the throttle body, injectors, fuel pumps, etc. for the vehicle, and changes to the crank sensor, reluctor, and ignition coil are Although there is a wide variety, it is not necessary to develop the installation of the intake air temperature sensor, so that it is easy to replace the carburetor system with the fuel injection system.

Here, FIG. 3B shows an example of a temporal transition of the intake air temperature and the like calculated by the internal combustion engine control device in the present embodiment. FIG. 3B shows the time course of the intake air temperature and the like when the throttle valve opening (throttle opening) is fully open.

When the throttle opening is fully open, the engine load increases, so the self-heating of the injector 7 increases compared to the emission travel mode. Therefore, the intake air temperature increase amount ΔTA calculated in the process of step S3 of the intake air temperature calculation process shown in FIG. 2 is the engine ambient temperature (thermistor temperature) detected in the process of step S1 of the intake air temperature calculation process shown in FIG. The transition P1 of the addition value added to (Tthr) deviates from the transition P0 of the actual measured value of the intake air temperature indicated by the solid line in FIG. 3B. Therefore, in the present embodiment, in the process of step S4 of the intake air temperature calculation process shown in FIG. 2, the corrected intake air temperature increase amount ΔTB is calculated by subtracting the injector injection amount subtraction value from the intake air temperature increase amount ΔTA, and FIG. In the process of step S5 of the intake air temperature calculation process shown, the intake air temperature TA is calculated by adding the corrected intake air temperature increase amount ΔTB to the engine ambient temperature. As a result, the transition P2 of the intake air temperature TA obtained by adding the corrected intake air temperature increase amount ΔTB to the engine ambient temperature substantially matches the transition P0 of the actual measured value of the intake air temperature as shown in FIG. 3B. Become.

However, since the rise characteristic of the intake air temperature is slower than the rise characteristic of the injector temperature, the intake air temperature TA tends to deviate from the actually measured value P0 of the intake air temperature at the rising edge. Therefore, in the present embodiment, in the process of step S6, in order to make the rise characteristic of the injector temperature and the rise characteristic of the intake air coincide with each other, the intake air temperature TA is subjected to filtering processing, and correction for delaying the rise characteristic of the intake air temperature TA is performed. . As a result, the corrected transition P3 of the intake air temperature TA coincides more accurately with the actually measured value P0 of the intake air temperature at the rise, as shown in FIG. 3B.

In the above-described internal combustion engine control apparatus according to the present embodiment, the ambient temperature of the internal combustion engine is acquired, the injector temperature that is the temperature of the injector 7 is acquired from the resistance value of the coil 7a of the injector 7, and the ambient temperature and injector temperature of the internal combustion engine are acquired. Therefore, the intake air temperature of the internal combustion engine is calculated by calculating the intake air temperature rise amount of the internal combustion engine and adding the intake air temperature rise amount to the ambient temperature, so that it can be practically installed in an actual vehicle including a motorcycle. Yes, it has a simple configuration and the storage capacity of the storage device such as the ROM of the control device can be reduced, so that the overall cost can be suppressed and the intake air temperature of the internal combustion engine is calculated with sufficient practical accuracy. be able to.

Further, in the internal combustion engine control apparatus according to the present embodiment, the intake air temperature rise amount is calculated using a correlation characteristic that defines the relationship between the difference temperature between the injector temperature and the ambient temperature and the intake air temperature rise amount. The intake air temperature rise amount correlated with the difference temperature between the injector temperature and the engine ambient temperature can be calculated using a correlation characteristic that defines the relationship between the differential temperature and the intake air temperature rise amount.

In the internal combustion engine control apparatus according to the present embodiment, the corrected intake air amount is calculated by calculating the injection amount correction value of the injector 7 from the fuel injection amount per unit time of the internal combustion engine and subtracting the injection amount correction value from the intake air temperature rise amount. Since the intake air temperature is calculated by calculating the temperature increase amount and adding the corrected intake air temperature increase amount to the ambient temperature, the intake air temperature is considered in consideration of the decrease in the intake air temperature due to the traveling wind according to the vehicle speed of the vehicle. By calculating the intake air temperature, the intake air temperature can be calculated accurately.

Further, in the internal combustion engine control apparatus according to the present embodiment, since the calculated intake air temperature is filtered, the intake air temperature is accurately calculated by matching the rise characteristic of the injector temperature and the rise characteristic of the intake air temperature. be able to.

Further, in the internal combustion engine control device according to the present embodiment, by calculating the atmospheric temperature of the engine with the temperature sensor in the internal combustion engine control device, it is possible to eliminate the need to separately provide an outside air temperature sensor outside the device, which is simple. The cost can be further reduced by the configuration.

(Second Embodiment)
<Configuration of internal combustion engine control device>
Next, the configuration of the internal combustion engine control apparatus according to the second embodiment of the present invention will be described with reference to FIG. The internal combustion engine control apparatus according to the present embodiment is also typically mounted on an internal combustion engine mounting body such as a general-purpose machine such as a generator or a vehicle such as a motorcycle. The internal combustion engine control device will be described as being mounted on a vehicle such as a motorcycle.

Here, in the configuration of this embodiment, the use of the

thermistor elements

12a and 12b is the main difference from the configuration of the first embodiment described above. In FIG. 4, parts having the same configuration as in FIG. 1A are assigned the same reference numerals and explanations thereof are omitted.

As shown in FIG. 4, the thermistor element 12a as the first temperature sensor is a region having the highest temperature in the casing 10a of the ECU 10 (typically, the distance to the heating element that is the ignition circuit 14 is about several millimeters). A chip thermistor arranged in a region close to a heating element), which exhibits an electrical resistance value corresponding to the temperature and outputs an electrical signal indicating a voltage corresponding to the electrical resistance value to the A / D converter 13 To do. The thermistor element 12a may be replaced with another temperature sensor such as a thermocouple as long as such an electrical signal can be output.

The thermistor element 12b as the second temperature sensor is an ambient temperature (outside temperature) that is the ambient temperature outside the casing 10a of the ECU 10 in the casing 10a of the ECU 10, that is, an ambient temperature that is the ambient temperature around the engine. A chip thermistor disposed in a region close to (outside air temperature) (typically a region close to the housing 10a whose distance to the housing 10a is about several millimeters), and an electric resistance value corresponding to the temperature And an electric signal indicating a voltage corresponding to the electric resistance value is output to the A / D converter 13. The thermistor element 12b may be replaced with another temperature sensor such as a thermocouple as long as it can output such an electrical signal.

The A / D converter 13 is an electric signal indicating the opening degree of the throttle valve of the engine output from the throttle opening degree sensor 4 and an electric signal indicating the oxygen concentration in the atmosphere sucked into the engine output from the oxygen sensor 5. The electrical signals output from the

thermistor elements

12a and 12b are converted from an analog form to a digital form, respectively. The A / D converter 13 outputs these electrical signals thus converted into digital form to the CPU 21.

<Arrangement position of thermistor element>
Next, the arrangement positions of the

thermistor elements

12a and 12b will be described more specifically.

The

thermistor elements

12 a and 12 b and the ignition circuit 14 are disposed in a housing 10 a that houses each component of the ECU 10. The ignition circuit 14 is typically a driver IC and is a component that generates the largest amount of heat in the housing 10a. The thermistor element 12a is disposed close to the ignition circuit 14 that generates the largest amount of heat in the housing 10a, and the thermistor element 12b is disposed farther from the ignition circuit 14 than the thermistor element 12a. ing. That is, the thermistor element 12a is arranged at a position where it is most directly affected by the heat generation of the ignition circuit 14 and becomes the highest temperature in the housing 10a, and the thermistor element 12b is most affected by the heat generation of the ignition circuit 14. It is disposed at a position that is most unlikely to be affected and is most affected by the atmospheric temperature outside the casing 10a close to the casing 10a (the atmospheric temperature of the ECU 10 and corresponding to the atmospheric temperature of the engine).

The internal combustion engine control device 1 having such a configuration calculates the atmospheric temperature of the engine by executing the following atmospheric temperature calculation process. Hereinafter, operation | movement of the internal combustion engine control apparatus 1 at the time of performing the atmospheric temperature calculation process in this embodiment is demonstrated more concretely.

<Atmosphere temperature calculation processing>
First, in the atmosphere temperature calculation process in the present embodiment, as a premise, the atmosphere is determined based on the first differential temperature ΔT12 obtained by subtracting the detection temperature T2 of the thermistor element 12b from the detection temperature T1 of the thermistor element 12a, and the detection temperature T2 of the thermistor element 12b. Table data indicating a correlation characteristic line in which a relationship with the second differential temperature ΔT2a obtained by subtracting the temperature Ta is previously stored in the ROM 18 is prepared.

The first differential temperature ΔT12 basically corresponds to the amount of heat generated by the ignition circuit 14, that is, the amount of heat generated by the ECU 10. The second differential temperature ΔT2a is determined based on the detected temperature T2 of the thermistor element 12b in consideration of the fact that the detected temperature T2 of the thermistor element 12b may differ from the engine ambient temperature Ta due to the influence of the amount of heat generated by the ignition circuit 14, etc. This corresponds to the temperature difference between T2 and the engine ambient temperature Ta.

In the atmospheric temperature calculation process in the present embodiment, the first differential temperature ΔT12 is calculated, and the second differential temperature ΔT2a corresponding to the value of the first differential temperature ΔT12 is obtained by searching the table data indicating the correlation characteristic line. Find the value of. Then, a value obtained by subtracting the second differential temperature ΔT2a from the detected temperature T2 of the thermistor element 12b is calculated as the engine ambient temperature Ta. As a result, the ambient temperature Ta is calculated by correcting the detected temperature of the thermistor element 12b with the detected temperature of the thermistor element 12a. Ta can be calculated.

In the internal combustion engine control device in the present embodiment described above, one of the thermistor element 12a disposed in the housing of the internal combustion engine control device 1 and the thermistor element 12b disposed in the housing at a position separated from the thermistor element 12a. Since the ambient temperature is calculated by correcting the detected temperature with the other detected temperature, the ambient temperature can be accurately calculated in addition to the effects of the first embodiment described above.

In this embodiment, the detected temperature of the thermistor element 12b is corrected with the detected temperature of the thermistor element 12a. However, the detection of the thermistor element 12a is performed by resetting the table data and searching the reset table data. The temperature may be corrected by the detected temperature of the thermistor element 12b.

The present invention is not limited to the above-described embodiments in terms of the type, shape, arrangement, number, etc. of the members, and departs from the gist of the invention, such as appropriately replacing the constituent elements with those having the same operational effects. Of course, it can be appropriately changed within the range not to be.

For example, in each of the above-described embodiments, the ambient temperature is calculated using the

thermistor elements

12, 12 a and 12 b in the ECU 10 correspondingly. However, even if the ambient temperature is calculated using a resistance value of a relay or the like in the ECU 10. Alternatively, a separate outside temperature sensor may be provided to measure the outside temperature.

Further, in each of the above-described embodiments, the intake air temperature increase ΔTA is calculated using a table that defines the relationship between the difference between the injector temperature and the engine ambient temperature and the intake air temperature increase ΔTA. The intake air temperature rise amount ΔTA may be calculated using a predetermined arithmetic expression that defines the relationship between the difference temperature between the engine temperature and the engine ambient temperature and the intake air temperature rise amount ΔTA.

Further, in each of the above-described embodiments, the intake air temperature is calculated by adding the corrected intake air temperature increase amount ΔTB to the ambient temperature. However, according to the required calculation accuracy of the intake air temperature, the injector temperature and the engine temperature are calculated. The intake air temperature may be calculated by adding the intake air temperature rise amount ΔTA corresponding to the temperature difference from the ambient temperature.

Further, in each of the above-described embodiments, the intake air temperature TA is filtered. However, when control that does not require the injector temperature rise characteristic and the intake air temperature rise characteristic to be matched is performed, the air temperature TA is filtered. It does not have to be.

As described above, the present invention can be practically mounted on an actual vehicle including a two-wheeled vehicle, has a simple configuration, and can reduce the storage capacity of a storage device such as a ROM of a control device. The internal combustion engine control apparatus capable of calculating the intake air temperature of the internal combustion engine with sufficient practical accuracy can be provided, and the internal combustion engine control apparatus for a motorcycle or the like because of its universal character It is expected to be widely applicable.

Claims

In the internal combustion engine control device including a control unit that controls the operating state of the internal combustion engine mounted on the internal combustion engine mounting body,
The controller is
Obtaining the ambient temperature of the internal combustion engine;
Obtaining an injector temperature which is the temperature of the injector from the resistance value of the injector of the internal combustion engine;
An intake air temperature rise amount of the internal combustion engine is calculated from the ambient temperature and the injector temperature,
An internal combustion engine control apparatus that calculates an intake air temperature of the internal combustion engine by adding the intake air temperature increase amount to the ambient temperature.
The controller is
2. The internal combustion engine according to claim 1, wherein the intake air temperature rise amount is calculated using a correlation characteristic that defines a relationship between a difference temperature between the injector temperature and the ambient temperature and the intake air temperature rise amount. Control device.
The controller is
An injection amount correction value is calculated from the fuel injection amount per unit time of the internal combustion engine,
The internal combustion engine control device according to claim 1 or 2, wherein the intake air temperature rise amount is corrected by the injection amount correction value.
The controller is
The internal combustion engine control apparatus according to claim 3, wherein the calculated intake air temperature is subjected to filtering processing.
A first temperature sensor disposed in a housing of the internal combustion engine control device;
A second temperature sensor disposed in a position away from the first temperature sensor in the housing;
Further comprising
The controller is
The ambient temperature is calculated by correcting one detected temperature of the first temperature sensor and the second temperature sensor with the other detected temperature of the first temperature sensor and the second temperature sensor. The internal combustion engine control device according to any one of claims 1 to 4.