TW552407B - Intake-air pressure detecting method for internal-combustion engine - Google Patents

Abstract

An intake pressure sensor 21 detects intake pressure influenced by intake pulsation in an intake passage 6 during operation of an engine 3. An electronic control unit (ECU) 20 calculates a lower limit value of the pulsating intake pressure and a threshold value appropriate for the rotational speed to determine the lower limit value as a calculated value of the intake pressure when the threshold value is smaller than the lower limit value. The ECU 20 calculates an amount of air to be taken in a combustion chamber 8 based on the value of the intake pressure obtained from the lower limit value and the detected value of the rotational speed. Based on the calculated intake amount, an fuel injection amount and an ignition timing are calculated. The ECU 20 controls an injector 4, an ignition coil 13, and others based on those calculated values.

Description

V. Description of the invention (1) The technical field to which the invention belongs The present invention relates to an intake air M detection method for detecting an intake pressure of a rotation parameter, a required operation: implementation of direct-use intake pressure detection, and: : 2 test methods set. ", Control technology of conventional control technology for various internal combustion engines, such as fuel injection control or exhaust gas recirculation control, in the conventional internal combustion engine. For example," in the so-called "D-J system" (measurement of intake air) Flux, :: Fuel injection system) of the engine, from the intake pressure and engine rotation, pressure: the intake amount of intake air into the engine's fuel chamber, according to the calculated ^ -injection, injection volume. However, in a reciprocating engine, the intake air pulsates due to the movement of the piston, and the intake air pressure also changes accordingly. Therefore, with the benefit method, the value of the intake air pressure detected by the pressure sensor is directly used as the operating number ^ The control of the gas turbine becomes unstable. Therefore, various technologies have been proposed so far for detecting and controlling the internal combustion engine after excluding the influence of the intake pressure pulsation. …, // In general technology, it is thought to smooth the fluctuation of the intake pressure accompanying the pulsation of intake pressure by performing a “smoothing process” on the detection value of the intake pressure sensor. The "smoothing process" is a process of averaging the detection values sampled at a predetermined period, and the degree of averaging can be arbitrarily set with the "smoothing coefficient". In addition, Japanese Patent Application Laid-Open No. 1-3 1938 discloses the same technique.

2097-4906-PF (N); Ahddub.p t d page 5 5. Explanation of the invention (2) Examples. That is, the intake pipe pressure measuring device is sampled during the driving cycle, and the intake pressure detected by the U :: device is determined at a predetermined value. On the other hand, the internal combustion broadcast value is added and averaged to calculate the calculated value of the average air pressure ', and the average value is used as the input directly during the operation, so that the fuel injection control will be used. After the constant speed of the internal combustion engine is averaged, the average value obtained by adding the average processing is used to calculate the value ′ for fuel injection ::: flat :: value: used as a smoothing process for the intake pressure ”. ： ； = :: Detection value: “Check the intake air pressure sensor at once in a while.”, The calculated values are used as the intake air pressure, which are used for :::; However, the method stabilizes the smooth rotation and makes the smoothing response during the rotation, and the calculated value of the pressure is generally the same as the actual fuel problem. In the past, the coefficient has become larger, the number of transient operations has become smaller, and the delay has been delayed. When setting the conventional usage of the slippery process in the constant speed operation of the conventional modification room, when the intake air pressure occurs, there will be an alarm when the meter responds when the meter is running. However, the measured value of the "smoothing phase of the intake air volume" has a tendency to be delayed even at a constant speed. On the contrary, although the calculation value is improved during the transition period, it tends to be unstable. As shown in Figure 13, the responsiveness of the air intake is also less than the accuracy of the calculated value, and the correlation is not sufficient. In the range of 2097-4906-PF (N); Ahddub.p t d page 6 552407

V. Description of the invention (3) The relationship between the calculated values of the intake pressure of the gas turbine load and the linear characteristics cannot be obtained. The applicant of this patent has found that in a four-stroke reciprocating bow engine, the variation of the intake pressure accompanying the pulsation of the intake air has a lower limit value of the intake pressure, i.e., near the dead point below the intake stroke The detected value becomes the best 进 气 which reflects the actual intake air pressure. It is thought to use it as the calculation and value of the intake air pressure. This has been proposed in Patent Application No. 20 00-29343 9. That is to say, a method for detecting the intake air pressure of an internal combustion engine is provided. When the internal combustion engine is running, as shown in Fig. 4, calculate the AD value of the intake air pressure accompanying the pulsation change "" lower limit value pm 1 0 "and then the lower limit. The value 叩 1 〇 is set as the final intake pressure PM which is the calculated value of the intake pressure. As for the proposed technology, the applicant of this patent repeats the results of the review and learns that the engine is running backblown (blwing-back ), Etc., as shown at times t1 and t2 in FIG. 14, in the case where the waveform of the AD value pmad is chaotic, the irregular lower limit value caused by the chaos may be erroneously detected as the lower limit value pm 1 of the intake pressure pulsation. 〇. In the case of such a detection error, the intake air volume of the engine is calculated to be more than the actual value. As the fuel injection volume is calculated due to the transition, the air-fuel ratio becomes leaner, which may cause driving or exhaustion. ^ Deterioration such as radiation deterioration.

Therefore, in view of the above circumstances, the present invention aims to provide a method for detecting the intake pressure of an internal combustion engine, which is excellent in stability and responsiveness, makes it possible to detect an intake pressure with a high correlation with the actual intake amount, and prevents the engine from reversing Incorrect detection of intake air pressure caused by blowing-back etc.

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The way to solve the problem is to achieve the above-mentioned purpose. For example, the invention of the first invention of the scope of patent application, the main purpose of the intake pressure detection method is, when the internal combustion engine is running: the lower limit of the intake pressure pulsation *, and the lower limit The limit values are calculated together according to the threshold value of the speed of the internal combustion engine. If the lower limit value is smaller than the threshold value, the lower limit value is determined as the calculated value of the intake pressure. "When the internal combustion engine is running" Because the intake pressure fluctuates and the intake pressure is accompanied by 1 movement "When the intake pressure is directly used for the control of the internal combustion engine, the control becomes unstable. Here, in the detected value of the intake pressure pulsation, it has been found that its lower limit value becomes the best intake pressure that reflects the actual intake volume. Therefore, if the lower limit of the intake pressure pulsation is calculated according to the structure of the invention, the lower limit value is determined as the calculated value of the intake pressure. Although the intake pressure is accompanied by the pulsation, the intake pressure is also related to the intake amount. Appropriate values and actions. Also, because the lower limit value is smaller than the threshold value calculated according to the rotational speed of the internal combustion engine, the lower limit value is determined as the calculated value of the intake pressure. For example, due to the back blowing of the internal combustion engine (blowing — 13 "1 ^, etc., The waveform is confusing, and the irregular lower limit value appears. Except for the irregular lower limit value, it will not be determined as the calculated value of the intake pressure. In order to achieve the above purpose, for example, the main purpose of the invention in the second patent application scope is 'In the intake pressure detection method of the internal combustion engine of the invention as claimed in the first item of the patent application range, the threshold is calculated by subtracting a predetermined set width from the upper limit of the intake pressure pulsation calculated together with the lower limit; Prediction based on the amplitude of the intake pressure pulsation at the speed during the high load and constant speed operation of the internal combustion engine

2097-4906-PF (N); Ahddub.ptd Page 8 552407 V. Description of the invention (5) Set the set value. If based on the structure of the invention, except for the effect of the invention, the intake steam = the low value of the upper limit of the lower limit of the upper limit of the scope of the application for patent application. High load constant speed operation value. Here, since the setting width is preset according to the width, the threshold value of the vibration of the intake pressure pulsation suitable for the rotation speed is obtained.比较 Comparing the lower limit value according to the speed to achieve the above purpose, such as applying & the main purpose is to apply the pressure detection method of the invention as described in the patent application No. ^ patent scope No. 3, Inventor's invention of the internal combustion engine, the threshold value of the calculation of the air intake speed is larger than the second threshold ^ When operating, the calculation ratio is smaller than the turning limit value and the lower limit value is determined to be ^ 3 3 Second, when the internal combustion engine is in transient operation, the calculated value is = ^. During operation, the amplitude of the variable air pressure pulsation relative to the lower limit value tends to be smaller than the constant speed. Therefore, if L according to the invention has the effect that the lower limit value is greater than the threshold value of the invention of item 1 within the scope of the invention, in addition to the second threshold value and the lower limit value,卩 卩 ... When the machine is in transient operation, the second threshold value is small. Because the lower limit value is compared with the second value, the lower limit value is equal to the detected intake air pressure corresponding to the transition time. In order to achieve the above-mentioned purpose, for example, applying the invention of the fourth invention of the air intake pressure detection device of the internal combustion engine to detect the intake pressure of the internal combustion engine; the lower limit ^: the detection value of the air intake pressure detection and installation pressure detection device is calculated in this拗 = 戽 Pei Zhi, according to the lower limit of the intake air; speed detection device, pick up the intake pressure pulsation when the engine is running, the speed of the J shai internal combustion engine; threshold

2097-4906-PF (N); Ahddub.ptd 552407 V. Description of the invention (β) A calculation device calculates a threshold value based on the detected rotational speed; and an intake pressure determination device, the lower value is lower than the threshold value The lower limit value is determined as the calculated value of the intake pressure in hours. If according to the structure of the invention, when the internal combustion engine is running, according to the detection value of the intake pressure detection device, the lower limit value calculation device is used to calculate the lower limit value of the intake pressure pulsation, and the threshold value calculation device is used to calculate the Threshold of speed detected by the device. However, when the lower limit value is smaller than the threshold value, the lower limit value is determined by the intake pressure determination device as the calculated value of the intake pressure. Although the intake pressure is accompanied by a pulsation, the intake pressure is also appropriately related to the intake amount. Values and moves. In addition, due to the chaotic waveform of the intake air pressure pulsation such as the blow-back of the internal combustion engine, an irregular lower limit value appears. Except for the irregular lower limit value, it is not determined as the calculated intake pressure. In order to achieve the above purpose, the main purpose of the invention of the fifth scope of the patent application is that the intake pressure detection device of the internal combustion engine of the invention of the fourth scope of the patent application includes a transition operation judgment device to judge the transition operation of the internal combustion engine. ; And a second threshold value calculation device, which calculates a second threshold value based on the threshold value of the transition operation of the internal combustion engine that is greater than the threshold value; when it is judged that the transition operation of the internal combustion engine, the intake pressure is determined The device selects a second threshold value calculated by the second threshold value calculation device that replaces the threshold value calculated by the threshold value calculation device. The lower limit value is smaller than the second threshold value and sets the lower limit value. Determined as the calculated value of the intake pressure. During the transient operation of the internal combustion engine, the amplitude of the intake pressure pulsation is smaller than that of the constant-speed operation, and its lower limit value is relatively large, and the lower limit value tends to be larger than the threshold value. Therefore, if according to the structure of the invention,

2097-4906-PF (N); Ahddub.ptd Page 10 552407 V. Explanation of the invention (7) Use the transient operation judgment device to judge the calculation of the ratio of the threshold value calculation device in addition to the effect of the invention of item 4 Comparison of the limits. The lower limit ratio is determined by the air pressure determining device, which determines the lower limit value of the corresponding intake air pressure during operation. In order to achieve the above-mentioned purpose, such as the control device of the internal combustion engine, the main purpose is the control device of the control object, the intake pressure of the internal combustion engine; the speed detection; the lower limit calculation device, according to the intake device calculated when the internal combustion engine is operating, Calculate the calculated value according to the detected setting; the lower limit value is smaller than the threshold value; the operation amount calculation device, the value and the detection value of the rotation speed calculation amount; and the control device controls the control amount by depending on the object of control . If constructed according to the invention,. Ten devices from the intake air pressure detection device Lower limit of intake pressure pulsation. A calculation device calculates that when the lower limit value is smaller than the threshold value according to the speed detection device, ^ is set to the calculated value of the intake pressure. In the transition of the internal combustion engine, reference is made to the calculation of the second threshold value, the limit value of the profit, and the value of the threshold. The threshold value of the nose is greater than the threshold value of the second threshold value.丄:, due to the use of <. Ten different values can be applied to the transition: 2: The invention of the 6th item = make: control the operation of the internal combustion engine = set: pressure detection device, detection / detection, detection of the intake pressure of the internal combustion engine The lower limit value of the detected value pressure pulsation of the device; the self-limit value ΐ the threshold value of the rotational speed; the intake pressure is determined; the lower limit value is determined as the intake pressure ^ according to the calculation of the determined intake pressure to obtain the desired Operation of control amount " " Operate according to the calculated operation amount. When the internal combustion engine is running, the control is calculated using the detection value of the detected intake air pressure at the lower limit value. During operation, the threshold value is set to detect Threshold of speed. However, the lower limit value is determined by the intake pressure, and the calculation is based on the determined intake pressure.

552407 V. Description of the invention (8) The measured value of the value and the rotational speed are obtained by using the operation amount of the control amount required by the operation and using the control device to obtain the control object of the operation and the control amount. Wrongly according to its operating volume, except for the chaos of the intake pressure pulsation, it will not be determined as the irregular lower limit value of the intake pressure value. The lower limit value is used as the calculation of the intake pressure. = Pulse the appropriate intake pressure, although the intake pressure is accompanied by the pulsation, attack the control: control of the target. Due to proper control of the intake air pressure, the control object y becomes unstable. According to the embodiment of the invention, the method of the present invention and the intake air pressure check using the detection method will be described in detail with reference to the drawings below. The specific intake of the control device of the internal combustion engine of the detection device. Figure 1 is a schematic diagram showing the structure of the engine car beta 7 ~, ^ ^ ^ ^ P | ^ ^ ^ of the present embodiment. The engine system contained in the vehicle includes the fuel storage. The built-in fuel fruit 2 is discharged from the fuel tank 1 and stored = 2 tank 1. / 、, 4 tanks, 1 reciprocating single-cylinder engine 3 is provided with fuel injection storage door: feed. In the internal combustion engine 2 "the discharged fuel is supplied to the injector 4 through the fuel passage 5. The supplied fuel ^" is operated to inject the fuel into the intake passage 6. The air milk is taken into the air intake passage 6 from the outside via an air cleaner. The air taken in the intake passage 6 and the fuel injected from the injector 4 form a combustible gas mixture and are drawn into the fuel chamber 8. A throttle valve 9 which is operated by a predetermined acceleration device (not shown) is provided in the intake passage 6. The throttle valve 9 is opened and closed to adjust the air (intake amount) of the fuel sucked in from the intake passage 6 to 8. A bypass passage 2097-4906-PF (N); Ahddub.ptd page 12 552407 is provided in the intake passage 6 5. Description of the invention (9) 1 0, bypass the throttle valve 9. An idle speed control valve (ISC valve) 11 is provided in the bypass path. The ISC valve 11 is actuated during idling, that is, the throttle valve 9 is full time to adjust the idling speed of the single-cylinder engine 3. The spark plug 12 provided in the fuel chamber 8 receives an ignition signal output from the ignition coil 13 and performs an ignition operation. The two parts 丨 2, 丨 3 constitute an ignition device for igniting the combustible mixed rolling supplied with fuel to 8. The combustible mixture inhaled by the fuel chamber 8 is exploded and burned by the ignition action of the spark plug 12. The exhaust gas after combustion is discharged from the fuel chamber 8 to the outside via the exhaust passage 丨 4 / the exhaust gas flowing through the exhaust passage 14 is purified by a ternary catalyst 5. Then, along with the combustion of the combustible mixture in the fuel chamber 8, the crank shaft 丨 7 rotates by the movement of the piston 丨 6 and the spring ′ is driven at the engine 3 to drive the vehicle. The vehicle is provided with an ignition switch 8 for starting the engine 3. The vehicle is provided with an electronic control unit (ECU) 20 for various controls of the engine 3. The battery 19 as a vehicle power source is connected via an ignition switch 18 * ECU20. Power is supplied from the battery 19 to the ECU 20 by turning on the ignition switch 18 '. Various sensors 2 1, 2, 2, 3, 2 and 4 installed in the engine 3 are used to detect various operating parameters related to the operating state of the engine 3, and are connected to the ECU 20 respectively. That is, the intake pressure sensor 21 of the intake pressure detection device provided in the intake passage 6 detects the intake pressure pm of the intake passage 6 on the downstream side of the throttle valve 9 and outputs an electric signal according to the detected value. signal. After the water temperature sensor 2 2 installed in the engine 3 detects the temperature (cooling water temperature) THW of the cooling water flowing inside the engine 3, it outputs an electrical signal according to the detected value. After the rotational speed sensor 23 of the rotational speed detecting device provided in the engine 3 detects the rotational speed (engine rotational speed) NE of the crank shaft 17, it outputs an electrical signal according to the detected value.

552407 V. Description of the invention (10): After the oxygen sensor 24 provided in the exhaust passage 14 detects the oxygen concentration (output voltage) in the exhaust gas to the exhaust gas 0x, the output will be based on the measured value of 0Sx. Electrical signal. The oxygen sensor 24 is used to obtain the air-fuel ratio A / {? Of the combustible mixture supplied to the fuel chamber 8 of the engine. After the night, the ECU 20 inputs various sensors 21 ~ 24 as described above. In order to execute batches according to these input signals ^ :: fuel injection control and ignition timing control, etc., K = f 'injection 仏 ⑼ 阙 11 and ignition coil U, etc., respectively. The value ^ 'ECU20 constitutes the lower limit calculation device of the present invention, the threshold = disadvantages; the air pressure determination device, the transition operation determination device, the second = counter Ling, the operation amount calculation device, and the control device. Detecting = Yan Huan rolling detection control is used to control according to the value calculated by the intake pressure sensor 21. ： Injection pressure is calculated from the influence of the intake pulsation. The injection control of the injector Γ is controlled according to the operating state of the engine 3 and according to the engine injection timing. The ignition timing control is based on the ignition timing of 12. Control ^ Ignition coil 13 'Control each Mars plug m \ lZ2rt ^ I ΐ 4 S ^ £ (CPU) input circuit and external (RAM), backup RAM, external input cpu, _, RAM and borrowing = Λ4Μ ° ECU20 The predetermined input circuit of the Bubu input circuit and external output control, which are formed by connecting circuits such as bus bars, etc., are established. _Remember in advance each spare MM of the engine 3 to store a pre-production formula. The RAM temporarily stores the operation results of the CPU.圮 k information in advance. CPU input via input circuit

552407 V. Various kinds of sensing of the description of the invention (11) | The detection signals of § 2 1 ~ 2 4 are executed according to the predetermined control program. The person-to-person describes the processing content required for the intake pressure detection control among the various controls performed by E C U 2 0. The flowchart of the intake pressure detection control routine is shown in FIG. The routine shown in FIG. 2 is executed periodically every predetermined period. In this embodiment, the ECU 20 executes this routine at a cycle of "lms". First, in step 100, the ECU 20 reads the value of the engine speed NE according to the detection value of the speed sensor 23. Next, at step 101, the ECU 20 reads the AD value pmad this time according to the intake pressure pm detected by the intake pressure sensor 21. Then, in step 102, the ECU 20 determines whether AE ^ pmad this time is greater than the previous AD value pmado. In this case, if the judgment result is negative, it is assumed that the intake air pressure pm has not risen 'At step 118, the ECU 20 sets the pressure rise flag XPMUP to "0" this time, and then proceeds to step 119. The pressure increase flag XPMUP is set to "1" when the intake pressure is increased, and set to "0" otherwise. In step 119, the ECU 20 determines whether the pressure rising flag xpmup is "1". In the case where the judgment result is negative, it is assumed that the intake air pressure pm then decreases last time, and E C U 2 0 moves the process to step 11 4. In the case where the determination result is affirmative, it is assumed that the intake air pressure pm is changed from rising to falling. In step 120, the ECU 20 sets the previous AD value pmado to the upper limit value pmhi, and then proceeds to step 114.

However, if the judgment result in step 102 is affirmative, it is assumed that the intake air pressure pm is increased. In step 103, the ECU 20 sets the pressure rise flag xpMUP this time.

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5. Description of the invention (12) Set to "1". Is XPMUPO "0"? The air pressure pm then rises last time, and the result is affirmative. The process moves to step 105. Next, in step 104, the ECU 20 determines the last pressure rising flag. In the case where the judgment result is negative, it is set to 'E C U 2 0 and the process proceeds to step 11 4. In this column ′, it is assumed that the intake air pressure pm changes from falling to rising, and it will be in step 105, and the ECU 20 judges whether the deceleration determination flag XGENS0KU is "0". The deceleration determination flag XGENS0KU is set to "1" when the engine 3 is decelerated, and otherwise set to "0". In this embodiment, the ECU 20 determines whether the engine 3 is in a decelerating operation state such as the final change in the intake air pressure pM value and the change in the detection value of the rotational speed sensor 23 according to this routine. Slowdown judgment flag 'XGENSOKU. Here, in a case where the determination result is negative, it is assumed that the deceleration operation of the engine 3 is performed, and the ECU 20 sets the preset value κρm for the deceleration to the setting width pmw in step 109. The setting width pmw is a parameter used for calculating a threshold value pthre described later. This predetermined value κρι can be set to, for example, "1.0 (mmHg)". If the result of the determination in step 105 is affirmative, and if it is determined that the engine 3 is not decelerating, the ECU 20 moves the processing to step 106. Then, in step 106, the ECU 20 determines whether the acceleration determination flag XKASOKU is "0". The acceleration determination flag XKASOKU is set to "1" when the engine 3 is accelerated, and otherwise set to r Q ". In this embodiment, the ECU 20 determines whether the engine 3 is in the final air pressure " value change and the change in the detection value of the rotational speed sensor 23, which are obtained later according to this routine.

552407 V. Description of the invention (13) Acceleration running state, set acceleration judgment flag XKAS0KU according to its judgment result. Here, in a case where the determination result is negative, when the acceleration operation of the engine 3 is set, the ECU 20 sets the predetermined value KP2 preset for acceleration at step 108 as the setting width pmw. The setting width pmw is a parameter used for calculating a threshold value pthre described later. The predetermined value KP2 can be set to be larger than the predetermined value KP1 of the deceleration day, for example, "3.0 (minHg)". On the other hand, if the result of the determination in step 106 is affirmative, and if it is set to the constant speed operation of the engine 3, the ECU 20 moves the processing to step 107. At step 107 ', the ECU 20 calculates the set width pmw by referring to the predetermined map. That is, as shown in FIG. 3, the ECU 20 calculates the setting width pmw according to the value of the engine speed NE read this time by referring to the data map preset with the engine speed NE and the setting width pmw as parameters. The setting width pmw in the data chart is preset according to the amplitude of the intake pressure pulsation according to the engine speed at the time of high load and constant speed operation of the engine 3. That is, when the throttle valve 9 is set to rw〇T (wide open

Throttle) ", as shown in Figs. 4 (a) to (c), the amplitude of the intake pressure pm varies according to the difference in engine speed NE. Figs. 4 (a) to (c) show the difference between the amplitudes at "1000 rpm", "500 rpm", and "2000 rpm". Therefore, in this embodiment, the setting width pmw is set in accordance with the magnitude of the amplitude of the intake pressure 叩, which varies depending on the value of the engine speed NE during high-negative operation. Ordice step 1107 ~ 109 moved to step 11 (). ^ 112〇_ The upper limit of the intake pressure pulsation different from the above ^ _hi minus the set width pmw to calculate the threshold pthre. # Then, in step ECU20, the ECU20 judges that the table turns from falling to rising and enters the table.

552407 V. Description of the invention (14) Whether the last AD value pmado of pressing pm is greater than the threshold pthre. In the case where the judgment result is affirmative, ECU20 directly shifts the processing to step 丨 4. In a case where the determination result is negative, in step 112, the ECU 20 sets the last AD value pmado to the lower limit value pm 1 of the intake air pressure pm. That is, the lower limit value pmlo of the valley of the pulsation is calculated from a plurality of AD values pmad obtained continuously from the intake air pressure pm accompanying the pulsation. Next, at step 11 3 'E C U 2 0, the lower limit value p m 1 〇 obtained this time is set to the final intake pressure PM required. Then, in step 114 ', which is moved from steps 119, 120, 104, 111, and 113, the ECU 20 sets the AD value pmad this time to the previous AD value pmado. Then, in step 115, the ECU 20 judges whether or not the pressure is ##. In the case where the judgment result is positive = step 116, the ECU 20 sets the last pressure rising flag χρΜυρ〇 to "丨". If the result of this determination is negative, in step 117, the ECU 20 sets the last pressure increase flag XPPMUP0 to "0". Dedicated to the next transport

Then, the ECU 20 completes the timing of the calculation cycle after completing the processing of this routine, and then performs the processing from step 丨 00. In this routine, after the pulsation of the intake pressure pm is calculated when the engine 3 is running, the lower limit value pmlo is determined as the lower limit value pml.

Control the final intake pressure pM of the calculated value of the intake pressure pm used. Therefore, as shown in Fig. 5, for the intake air with pulsation, compare the sampling, AD iPmad0 and the current value 叩 ad, to determine the transition of the decrease in intake air pressure pm. Then, in the transition from rising to falling

2097-4906-PF (N); Ahddub.ptd Page 18 552407 V. Description of the invention (15) pmado is calculated as the upper limit value pmh i, and the last AD value pmado when the conversion from falling to rising is calculated as After the lower limit value pml0, the lower limit value pmlo is determined to be the final intake pressure pm.

Here, in this routine, as shown in FIG. 6, after the threshold value pthre is obtained from the upper limit value pmhi and the set width pmw, when the lower limit value pmi0 is smaller than the threshold value pthre ', the lower limit value pm is made. 10 is determined as the final intake pressure PM which is the calculated value of the intake pressure pm. Therefore, as shown by a circled circle in FIG. 6, an irregular lower limit value appears in the AD value pmad, and also in the case where the irregular lower limit value is greater than a threshold value pthre. Except for the irregular lower limit, it will not be determined as the final intake pressure PM. In the engine system of this embodiment, fuel injection control is performed using the final intake pressure PM detected as described above. Therefore, the processing content of the fuel injection control will be described next. Fig. 7 shows a flowchart of a fuel injection control routine. E C U 2 0 This routine is executed periodically during a predetermined period of time. First, in step 200, the ECU 20 reads the value of the engine speed NE according to the detection value of the speed sensor 23. In step 210, the ECU 20 reads the final intake pressure pM. That is, the lower limit value pml0 of the intake air pressure accompanied by the pulsation is read as the final intake air value 0 "

Produced in step 220, the ECU 20 calculates the basic fuel injection amount TAUBSE based on the read value of the engine speed ㈣ and the value of the air pressure PM. ECU20 uses the function data (injection amount map) determined in advance by e to calculate the basic fuel 9 = TAUBSE. In this function data, the value of the intake air pressure pM and the engine speed determine the intake air volume |

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V. Description of the invention (16) Basic fuel injection amount TAUBSE. In step 2 3 0 'E C U 2 0, the value of the cooling water temperature THW is read in accordance with the detection value of the water temperature sensor 22. Then, in step 240, the ECU 20 calculates a warm-up correction coefficient KTHW for correcting the basic fuel injection amount TAUBSE according to the read-in value of the cooling water temperature THW and according to the warm-up state of the engine 3. At step 250 ', the ECU 20 reads the value of the air-fuel ratio correction coefficient FAF for correcting the air-fuel ratio A / ρ of the combustible mixture of the air supplied to the fuel chamber 8 and the fuel. The air-fuel ratio correction factor FAF is calculated based on the value of the oxygen concentration 0χ read from the detection value of the Zhao self-tester 24: "At step 260, the ECU 20 corrects by using the warm-up correction factor to increase the fuel ratio with * The coefficient FAF and the like correct the basic fuel injection amount TAUBSE calculated as described above to calculate the value of the final fuel injection amount TAU. Then, in step 270, the ECU 20 controls the injection in accordance with the calculated value of the most anticipated injection amount TAU. The injector 4 controls the fuel injection from the injector 4. "," In the engine system of this embodiment, the ignition timing control is performed using the J pressure PM as described above. Because of &, explain the processing of I; FIG. 8 shows the routine of the ignition timing control. The control ECU 20 executes this routine periodically at predetermined intervals. First, at step 300, the ECU 20 reads the value of the engine speed NE in accordance with the speed sense. Detection value In step 310, the ECU 20 reads the value of the final intake pressure pM. ^ = Lower limit pral of pulsating intake pressure ⑽. As the final step.

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a ... In step 320, the ECU 20 calculates the basic ignition timing ITBSE based on the read value of the engine speed NE and the value of the feeding fPM. The ECU 20 calculates the basic ignition timing and ITBjE by referring to predetermined function data (ignition timing control map). After the function data is determined from the value of the intake air MpM and the value of the engine speed, the amount of intake air taken in by the fuel chamber 8 of the engine 3 is determined, and the basic ignition timing ITBSE is determined according to the intake air amount. In step 330, the ECU 20 reads the value of the water temperature THW according to the detection value of the water temperature sensor 22. Then, in step 34, the ECU 20 reads

The value of the cold water temperature THW is calculated according to the warm-up state of the engine 3 to modify the warm-up correction coefficient κι of the ITBSE during the basic ignition period. At step 350, the ECU 20 calculates the final ignition timing I τ by modifying the basic ignition timing IT B S E calculated as described above in accordance with the warm-up correction coefficient. Then, in step 360, the ECU 20 controls the ignition coil 13 by controlling the ignition coil 13 according to the calculated value of the final ignition period it, and controls the ignition timing of the spark plug 12. In the engine system of this embodiment described above, the pulsation of the intake air occurs in the intake passage 6 while the engine 3 is running π, and the intake pressure pm detected by the intake pressure sensor 21 is accompanied by the pulsation. Therefore, when the intake air pressure 伴随 associated with the pulsation is directly used as one of the operating parameters for performing various controls of the engine 3, the control becomes unstable.

Here, the applicant of this patent has found that the lower limit value pmlo becomes the best reflection of the amount of intake f that is actually absorbed by the fuel chamber 8 at the detected value of the intake air pressure pm accompanied by the pulsation. Therefore, the intake pressure detection method performed in this engine system 'makes the lower limit value pm 1 〇 for the intake pressure pulsation accompanying the pulsation of the intake pressure, that is, the pulsating intake pressure pm, and determines its lower limit value pm 1 〇 as the final intake pressure. pm.

V. Description of the invention 〇8) Therefore, 'Although the intake air accompanied by pulsation _: an appropriate value and amount related to the intake air volume :::: the final intake air pressure PM is excellent' can be detected and actual a in stability and response Alas. The advancement of Δinterval ... The final intake air with high correlation is shown in Fig. 9 (a) and (b), which is a timing chart showing the relative disuse. In Figure H, the intake air glow d 'with a change in the degree of arrest is shown by the solid line of the two-point linked line table showing the heart pressure of the intake dust by this implementation. Progress »Smoothing progress of the alpha processing is also known from this timing diagram. In the case of the acceleration of the opening without change in the combination, the": "Ke and acceleration are completed" are equipped to accelerate from the beginning to the acceleration; . In addition, it was learned that when the PM is also in a rapid and rapid transition operation between ',', and $, the smoothing of the intake pressure is more stable than the moment when the past speed is completed as indicated by the two-point chain line. At the time t2, the intake air pressure PM in the form of t continuous application becomes stable. Therefore, the second smoothed intake air pressure falls behind the atmospheric pressure detection method, which can detect the change of the geese: = the intake air pressure PM at the time of advancement according to this embodiment. I response is improved between two ❹1 U, t2. Figure 10 shows the relative shaping. It is known from the graph that the increase of the load relative to the calculation characteristic of the intake air pressure at 2 loads increases in a curve, and the second slip, the air pressure increases linearly with the negative of the engine. That is, it is known that the intake air pressure ㈣ 'of this embodiment is linear. This means relative; = the intake air pressure_ linearly reacts with the intake air pressure PM of the engine A, Table = the throttle of the accelerator device 9 of the action clothing π the sound of the intake air pressure PM detected during the transition 2097-4906-PF ( Ν); Ahddub.ptd Page 22 552407

Improved responsiveness. Because of m, it is known that the intake air volume converted from the intake MPM is more accurate than the smoothed air pressure conversion. One person, however, "when blowing-back occurs during operation of the engine 3 of this embodiment, the wave of the intake pressure pulsation in the intake passage 6 is chaotic" may be caused by irregularities caused by the chaos. The limit value appears after mixing with the normal lower limit of precession. For this phenomenon, in this embodiment, the lower limit value of the AD value pmad with the pulsation advance pm is calculated, and the calculation is based on the advent of the engine speed ne = the value pthre. In calculation, when the value of the lower limit value is smaller than the threshold value pthre, it will be the lower value of the lower limit value to determine the final intake pressure pM which is the calculated value of the intake pressure pm. Therefore, for example, the blow-back of the engine 3 and the pulsation of the intake air pressure pm, the waveform is chaotic, and the lower limit of the irregularity occurs, and the lower limit of the irregularity is excluded from the normal lower limit. The limit value does not determine the lower limit value of the irregularity for the final intake air pressure PM. Therefore, due to the “back blowing” of the engine 3, blowing-back, etc., the pulsation of the intake air pressure is turbulent, and the detection error of the final intake air pressure PM can also be prevented. Furthermore, in this embodiment, the lower limit and Calculate the upper limit value pmhi together with the value pml〇 as a reference, and take the value of the set width pmw smaller than the upper limit value ⑽] to calculate the threshold value pthre. Here, because the set width pmw is According to the amplitude preset according to the difference in the engine speed NE of the intake pressure pulsation during high-load constant-speed operation of the engine 3, at the threshold pthre, the lower limit pml suitable and changed by the engine speed NE is obtained. The value of the comparison. Therefore, the confusion of the intake pressure pm caused by blowing-back, etc.

2097-4906-PF (N); Ahddub.ptd Page 23 552407

V. Description of the invention (20) Except the irregular lower limit due to the difference in engine speed NE, the detection of PM is incorrect. The change is also due to the proper lower limit from the normal limit to prevent the final intake pressure here. During the transient operation of engine 3, that is, during deceleration operation and f operation, the amplitude ratio of the intake pressure pulsation is constant. When the operation is small, the lower limit value pmlo of the intake pressure pulsation is also relatively large. Is there a lower limit value than a threshold value? ^ 1 ^ Big tendency. For example, when the engine 3 is rapidly accelerating, as shown in FIG. U, at time t1 to t2, during the temporary period after the throttle valve 9 is suddenly opened, the amplitude ratio of the pulsation waveform of the AD value pmad of the intake pressure pm is connected at the time. When the fixed-speed operation (high load) after t2 has a small pulsating waveform, the AD value ⑽ ^ lower limit value pmlo is larger than the threshold value pthre. Therefore, between the time t1 and t2 immediately after the acceleration of the engine 3, although the intake air volume for the engine 3 increases, the detected final intake pressure PM is still a small value. As a result, the final fuel injection amount T A U calculated in accordance with the intake air pressure μ and the like becomes smaller, and the leaner fuel-air ratio engine speed NE does not increase, which may result in deterioration of the stumbHng driving performance. Therefore, in this embodiment, during the transitional operation of the engine 3, the threshold value (the first threshold value) pfhre which is different from the threshold value calculated from the known engine speed NE is calculated, and is different from the threshold value that is calculated. (Second Threshold) Comparison of pthre and lower limit pmlo. That is, the second threshold value pthre calculated by referring to the preset value KP1, KP2 and the upper limit value pmhi, which are smaller than the set width pmw calculated in accordance with the engine speed NE for use during deceleration or acceleration, is set to be smaller. Comparison with lower limit pmlo. However, the lower limit value pmlo is smaller than the second threshold value pthre, because the lower limit value pmi0 is determined as the final advance.

2097-4906-PF (N); Ahddub.ptd Page 24 552407 V. Description of the invention (21) Air pressure PM, the final intake pressure PM can be detected according to the transition operation. Therefore, the detection error of the final intake pressure PM during the transient operation can be reliably prevented. That is, during the rapid acceleration of the engine 3, as shown in FIG. 12, the threshold value pthre becomes the limit value pthre not shown in FIG. 11. The lower limit value pmlo of the AD value pmad at time t1 to t2 does not become greater than Its threshold is pthre large. Therefore, it is possible to appropriately grasp the lower limit value p m 1 of the AD value p m a d which increases sharply immediately after the rapid acceleration. As a result, at the moments 11 to 12 immediately after the acceleration of the engine 3, it is also possible to appropriately detect the final intake air pressure PM as the intake air of the engine 3 increases. That is, the intake pressure can be appropriately detected in accordance with the transient operation of the engine 3. However, in this embodiment, since the appropriately detected intake air pressure is taken into the fuel injection control and ignition timing control, an appropriate intake air amount can be calculated, and appropriate fuel injection control and appropriate during the transition operation can be performed. Control of ignition time. As a result, the engine 3 can achieve a transition with excellent responsiveness. In addition, for example, there is a response delay during rapid acceleration, and the final fuel injection amount TAU in the intake air is reduced, and the air-fuel ratio A / F is not depleted. 2 In this embodiment, during rapid acceleration, The final fuel injection amount TAU of the air / air volume is obtained, and the air / fuel ratio A / ρ is appropriately adjusted to smoothly increase the engine speed NE and ensure proper driveability. If the engine system according to this embodiment is detected by the engine 3 ECU20 from the intake pressure sensor 21 ^ 瞀, the company a ντ full, then the AD value pmad into the bunker Pm is the lower limit of the intake pressure pulsation pml〇. Once p D is hit by the lead wire detected by the speed sensor 23, the ECU 20 ⑽re. In addition, the lower limit value of the ratio of the engine speed NE to the threshold value is calculated. The lower limit value p 卩 4 is smaller than the threshold value Pthre, and the ECU 20 determines the lower limit value pmlo as the value of the oxygen intake ceremony pm. Final air intake

552407 V. Description of the invention (22) The pressure of PM〇ECU20 according to the Zhaotian Institute ^ .. λΤΓ ^…, the final intake pressure PM value of the catty, 疋 and the engine end fire period Ιτ, as the most expected injection of 彳 U The amount of TAU and the maximum ^ ΛΛΤΤΤ is the first operation. Then, the ECU 20 executes the glow injection control and the ignition timing control in accordance with the remaining TAU and IT # 1, 1H & A, and + A, and a firing state 4 and an ignition coil 13. . The value of the ^ self-semi- / semi-pulsating intake air pressure will not be included in the search for the value of ^ AD ^ pmad ^ ^ ^ ^ =, except for the appropriate lower limit The final entry of the lower limit is ^ deleted. The control of taking in the injector 4 and the ignition coil 13 is as follows: This' exhaustible intake pressure pm is accompanied by pulsation and chaos occurs in its pulsation. It is also prepared to be the final fuel injection for the operating amount. The value of the amount TAU and the final ignition timing IT are appropriately controlled in accordance with the behavior of the intake pressure pm, the injector 4 and the ignition coil 13 and so on. As a result, it is possible to perform ignition control and ignition timing control with excellent stability and responsiveness, and perform correct fuel injection control and ignition timing control with the same correlation with the actual intake air volume and little influence of the fluctuation of the air pressure pulsation. . At the same time, it can perform stable control without being affected by the blow-back of the engine 3. In addition, the present invention is not limited to the above-mentioned embodiments, and may be implemented as shown below without departing from the spirit of the present invention. ° (1) In the embodiment described above, the engine system including the single-cylinder engine 3 embodies the intake pressure detection method, the intake pressure detection device, and the control device of the internal combustion engine of the present invention. However, the number of cylinders may be two. The engine system of a cylinder, a three-cylinder, or an engine with three or more cylinders is embodied. However, if the number of cylinders is larger, the amplitude of the intake pulsation is smaller, so the effect of the present invention can be said.

2097-4906-PF (N); Ahddub.ptd page 26 552407 V. Description of the invention (23) It is particularly effective in engines with cylinder number bu 3. (2) In the embodiment described above, the control embodies the present invention, but b fuel injection control and ignition timing limit the intake pressure as the operating parameter H to these controls, and can also be used to make exhaust gas return Controls and other controls. If the effect of the invention is based on the patent application No. 1 and excellent responsiveness, it can detect the structure that is practical and realistic, and it can detect the pressure of the internal combustion engine with high stability and prevent the reverse of the internal combustion engine. error. 0Wlng —back), etc., such as ⑴〇wln "ack) and so on, the back blowing of the internal machine can prevent the detection error of the intake air pressure. The effect of the invention in the scope of the patent item == structure except for the application operation According to the transition of the internal combustion engine, according to the fourth item of the scope of the patent application, the start and stop and responsiveness are excellent, and the detectable structure is qualitative pressure in the female, and it can prevent the high correlation of the engine volume. Incorrect detection of intake air pressure — reverse-ng-back) etc. Intake operation is properly performed. Intake is performed in accordance with the transition of the internal combustion engine. The structure is excellent in stability and responsiveness, it can detect the intake air pressure with high correlation with the actual intake air volume, and at the same time it can perform stable control without being affected by the blow-back of the internal combustion engine.

2097-4906-PF (N); Ahddub.ptd Page 28 552407 Brief Description of Drawings Figure 1 shows the general structure of an engine system in an embodiment. Figure 2 shows the flowchart of the intake pressure detection control program. Back to figure. Figure 3 shows the relationship between the set width with respect to engine rotation. Figures 4 (a) ~ (c) show the differences in the intake pressure pulsation waveforms. Figure 5 shows the AD values of the intake pressure with pulsations. . FIG. 6 shows the values of the heart rate of the intake pressure accompanying the pulsation. Fig. 7 is a flowchart showing a program of fuel injection control. Fig. 8 shows the process of ignition timing control. Fig. 9 (a) and IX are timing charts showing the relative actions. The degree of opening and the combined intake air pressure are shown in Figure 10, relative to the engine load. Fig. 11 is a timing chart of the calculation characteristic of the intake air pressure of the halberd. Figure 12 shows the timing diagram of the air intake dust AD value during acceleration operation. Behavior of the AD value of the basic pressure of f, etc. Fig. 13 is a timing chart showing the conventional intake pressure. Fig. 14 is a timing chart showing a conventional method for detecting the intake pressure. Explanation of Symbols 3 Engine (Internal Combustion Engine) 1 2 Spark Plug (Control Object) b Intake Path 1 3 Ignition Coil (Control Object)

IHII 2097-4906-PF (N); Ahddub.ptd Page 29 552407 Brief description of drawings 2 3 Speed sensor (speed detection device) 4 Injector (fuel injection valve, control object) 2 1 Intake pressure sensor (Intake pressure detection device) 2 0 ECU (lower limit value calculation device, threshold value calculation device, intake pressure determination device, transient operation determination device, second threshold value calculation device, operation amount calculation device, and control device) 2097- 4906-PF (N); Ahddub.ptd Page 30

Claims (1)

552407 — VI. Patent application scope 1 · A method for detecting the intake pressure of an internal combustion engine, which is characterized by: · Calculating the lower limit value of the intake pressure pulsation when the internal combustion engine is running, and calculating the threshold according to the speed limit of the internal combustion engine together with the lower limit value And the lower limit value is smaller than the threshold value, and the lower limit value is determined as the calculated value of the intake pressure. 2 · The method for detecting the intake air pressure of an internal combustion engine as claimed in item 1 of the scope of patent application, wherein the threshold value is calculated by subtracting a predetermined set width from the upper limit value of the intake pressure pulsation calculated together with the lower limit value; According to the vibration of the intake pressure pulsation at the speed when the internal combustion engine is running at a constant load speed 3 · If applying for a special method, in which the lower limit is set when the calculated threshold value is large 4. An internal combustion air intake pressure detection The calculation of the limit value is calculated by calculating the threshold value of the operating speed detection device of the internal combustion engine; and the threshold value. The second value of the internal combustion engine determines the advancement of the engine, the device, and the setting of the inspection device at the time of rotation. When the transient operation of the intake pressure detection side of the internal combustion engine of the first item is calculated, the ratio is calculated according to the threshold of the speed. The limit value is a calculated value of the intake pressure than the second threshold. The air pressure detection device is characterized by: detecting the intake air pressure of the internal combustion engine; measuring the lower limit value of the intake pressure pulsation according to the detection value of the intake pressure detection device; measuring the speed of the internal combustion engine; and calculating the speed according to the threshold of the detected speed The air pressure determines the setting, and the value is determined as the value of the intake pressure calculated when the lower limit value is smaller than the threshold value. The lower limit 2097-4906-PF (N); Ahddub.ptd Page 31 552407 ------------------ VI. Scope of patent application5. The intake pressure detection device 'includes: a transition operation judging device for judging the transition operation of the internal combustion engine; and a second threshold value calculation device for calculating a threshold value greater than the threshold value based on the threshold value of the transition operation of the internal combustion engine. A second threshold value; when it is judged that the internal combustion engine is in transient operation, the intake pressure determination device selects a second threshold value calculated by the second threshold value calculation device that replaces the threshold value calculated by the threshold value calculation device The lower limit value is smaller than the second threshold value, and the lower limit value is determined as the calculated value of the intake pressure. 6, A control device for an internal combustion engine, which is a control device for controlling a control object regarding the operation of the internal combustion engine, which is characterized by: an intake pressure detection device that detects the intake pressure of the internal combustion engine; a rotational speed detection device that detects the speed of the internal combustion engine; μ Lower limit value calculation device, according to the detection value meter # of the intake pressure detection device, the lower limit value of the intake pressure pulsation during the operation of the internal combustion engine; the threshold calculation device, which calculates the threshold value according to the detected rotational speed Value; intake pressure determining device, the lower limit value is smaller than the threshold value, the lower limit value is determined as the calculated value of the intake pressure;) the operation calculation device, according to the calculated value of the determined intake pressure and the 4 speed The measured value is calculated to obtain the operation amount of the desired control amount; and the control device's operator operates the control pair in accordance with the operation amount calculated by the side. 2097-4906-PF (N); Ahddub.p t d 552407 Sixth, the scope of patent application, control the amount of control. imi p. 33 2097-4906-PF (N); Ahddub.p t d