JP2009013792A - Operation control device for internal combustion engine - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To achieve operation control having improved combustion while simplifying computing and reducing the number of parts, in an operation control device for an internal combustion engine which controls the operation condition of the internal combustion engine by a control map using as a variable a factor changed according to the operation condition of the internal combustion engine and which uses the factor as the angular velocity fluctuation of a crank angle. <P>SOLUTION: In this operation control device, the tip part 6a and rear end part 6b along the rotating direction of a crankshaft 4, of one reluctor 6 of at least one reluctor 6 arranged on the crankshaft 4, are detected by a pulser pickup 7 according to the rotation of the crankshaft 4, and a calculation means 11 calculates the angular velocity fluctuation of the crank angle based on a pulse interval from the pulser pickup 7. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to an operation control device for an internal combustion engine that controls an operation state of the internal combustion engine by a control map having a variable that changes according to the operation state of the internal combustion engine as a variable, and wherein the factor is an angular velocity fluctuation amount of a crank angle.

Operation control of the internal combustion engine by switching the control map based on the measured intake negative pressure, or the predicted intake negative pressure from other measured values, as a factor, in order to improve combustion such as fuel efficiency improvement of the internal combustion engine Patent Document 1 and Patent Document 2 and the like are known.
JP 2000-265894 A JP 2004-108289 A

  However, those disclosed in Patent Document 1 and Patent Document 2 require a relatively complicated calculation composed of several factors depending on the negative pressure sensor and other sensor equipment used for prediction of intake negative pressure and the like. It was. As for the detection of the crank angle, it is necessary to detect a plurality of pulses by a plurality of reluctors provided on the crankshaft. However, in the operation control of the internal combustion engine for improving combustion, if the calculation can be simplified and the number of parts can be reduced, it can be applied to a relatively low-priced motorcycle, which can lead to further environmental improvement. It will be possible.

  The present invention has been made in view of such circumstances, and provides an operation control device for an internal combustion engine capable of realizing operation control with improved combustion while simplifying calculation and reducing the number of parts. The purpose is to do.

  In order to achieve the above object, according to the first aspect of the present invention, the operating state of the internal combustion engine is controlled by a control map having a variable that varies depending on the operating state of the internal combustion engine as a variable, and the factor is the amount of change in the angular velocity of the crank angle. In the operation control apparatus for an internal combustion engine as described above, a front end portion and a rear end portion of one of the relucters provided on the crankshaft along the rotation direction of the crankshaft are detected according to the rotation of the crankshaft. And a pulsar pickup for outputting a pulse, and an arithmetic means for calculating an angular velocity fluctuation amount of the crank angle based on an interval between pulses output from the pulsar pickup upon detection of the front end portion and the rear end portion. It is characterized by.

  According to a second aspect of the present invention, in addition to the configuration of the first aspect of the present invention, a relucter that detects the front end and the rear end with the pulsar pickup has a crank angle before compression top dead center. It is provided on a shaft.

  In addition to the configuration of the invention described in claim 1, the invention described in claim 3 is provided so that a reluctator that detects the leading end and the trailing end with the pulsar pickup detects a reference ignition timing of the internal combustion engine. It is provided in the rotor of a generator, The said reluctator is used for the detection of the said reference ignition timing, and the calculation of the angular velocity fluctuation amount of the said crank angle.

  According to the first aspect of the present invention, the leading end and the high end along the rotation direction of one reluctator are detected by the pulsar pickup according to the rotation of the crankshaft, and based on the interval of the pulses output from the pulsar pickup. The number of parts required to detect the factors that change according to the operating state of the internal combustion engine because the operating state of the internal combustion engine is controlled by a control map that calculates the angular velocity fluctuation amount of the crank angle and uses the angular velocity fluctuation amount as a variable. In addition, the calculation can be simplified and combustion can be improved.

  According to the second aspect of the invention, since the angular velocity fluctuation amount is obtained at the crank angle before the compression top dead center, the angular velocity fluctuation amount is accurately obtained by obtaining the angular velocity fluctuation amount at a portion where the angular velocity fluctuation amount is relatively large. It is possible to obtain an accurate angular velocity fluctuation amount.

  According to the third aspect of the present invention, the reluctator provided on the rotor of the generator for detecting the reference ignition timing of the internal combustion engine is used for detecting the reference ignition timing and calculating the angular velocity fluctuation amount of the crank angle. Therefore, the operation control of the internal combustion engine can be performed with only one relucter of the generator. Thus, for example, an inexpensive generator for an internal combustion engine that does not control the ignition timing or the fuel injection amount only by detecting only the reference ignition timing can be used. This makes it easy to reduce the cost of an internal combustion engine that performs operational control.

  DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiments of the present invention will be described below based on examples of the present invention shown in the accompanying drawings.

  1 to 6 show a first embodiment of the present invention. FIG. 1 is a diagram showing the overall configuration of an operation control device for an internal combustion engine, and FIG. 2 is a diagram showing the relationship between the output timings of a relaxor and a pulsar pickup. 3 is a diagram showing the relationship between the stroke of the internal combustion engine, the reluctator and the crank angular velocity, FIG. 4 is a flowchart showing the control procedure by the control unit, FIG. 5 is a diagram showing a control map for determining the ignition timing, and FIG. It is a figure which shows the change of the crank angular velocity in the vicinity of a point.

  First, in FIG. 1, a carburetor 2 is interposed in an intake pipe 1 of an internal combustion engine EA having four cycles. The intake air amount and the fuel supply amount are controlled by the carburetor 2, and the internal combustion engine is ignited by ignition of a spark plug 3. Fuel is burned in the EA.

  A rotor 5 of a generator ACG is fixed to the crankshaft 4 of the internal combustion engine EA, and this rotor 5 is provided with one reluctator 6 at a crank angle position determined by a reference ignition timing before compression top dead center. The relaxer 6 is detected by a pulsar pickup 7 in accordance with the rotation of the crankshaft 4, and the pulsar pickup 7 has a front end portion 6 a and a rear end portion 6 b along the rotation direction 13 of the crankshaft 4. Is detected according to the rotation of the crankshaft 4 and a pulse is output.

  Thus, as shown in FIG. 2, the pulsar pickup 7 has a rising pulse corresponding to detecting the tip 6a along the rotation direction 13 of the reluctator 6 according to the rotation of the crankshaft 4, and the rotation direction. 13 and a falling pulse corresponding to the detection of the rear end portion 6b of the reluctator 6 is output. Thus, when the reluctor 6 is provided in the range of the angle θ centered on the axis of the crankshaft 4, the pulsar pickup 7 outputs a rising pulse and a falling pulse at intervals of the crank angle θ. If the time between the output timings of the rising and falling pulses is τ and the change amount of the angular velocity between the rising and falling pulses output from the pulsar pickup 7 is ωtdc, ωtdc = θ / τ It becomes.

  Incidentally, as shown in FIG. 3, the crank angular speed ω varies for each stroke of the four cycles. In the compression stroke, the crank angular speed ω is greatly reduced due to the occurrence of compression resistance in the combustion chamber. In the combustion / expansion stroke, the crank angular velocity ω is greatly increased due to the generation of crank rotational energy due to the pressure increase in the combustion chamber accompanying combustion, and in the exhaust stroke, the combustion is terminated and the crank angular velocity ω reaches a peak. The crank angular velocity ω decreases as mechanical friction resistance and exhaust gas discharge resistance due to exhaust later occur. Further, in the intake stroke, the crank angular velocity ω decreases due to pump work such as suction resistance. To do.

  In addition, when the rotational speed Ne of the internal combustion engine EA, that is, the average value ωa of the crank angular speed indicated by the chain line in FIG. 3 is the same, the crank angular speed ω at a high torque and a high intake air amount is as indicated by the solid line in FIG. The crank angular speed ω changes when the torque is low and the intake air amount is low, as shown by the broken line in FIG. 3. The higher the output torque and the larger the intake air amount, the greater the fluctuation of the crank angular speed ω. Become.

  The output signal of the pulsar pickup 7 is input to an electronic control unit 8A, and the electronic control unit 8A includes a CPU 9A and a memory 10A composed of RAM, ROM, etc., and the CPU 9A The function of the calculation means 11 for calculating the rotational speed of the internal combustion engine EA and the angular velocity fluctuation amount of the crank angle based on the interval between the rising and falling pulses output from the pulsar pickup 7 and the calculation result of the calculation means 11 And a function of processing means 12A for determining the ignition timing of the spark plug 3 on the basis thereof. Further, the memory 10A stores in advance a correction coefficient map of correction coefficients for correcting the ignition timing in accordance with the intake air temperature and the engine temperature (or the coolant temperature).

  The electronic control unit 8A controls the ignition timing of the spark plug 3 according to the procedure shown in FIG. 4, and the processing of step S1 to step S4 is executed by the computing means 11, and the processing of step S5 to step S7 is performed. Is executed by the processing means 12.

  In step S1 in FIG. 4, the rotational speed Ne (ωa) of the internal combustion engine EA is calculated. In this embodiment, one of the rising and falling edges output from the pulsar pickup 7 is determined by a predetermined number N. It is calculated based on the time T required for counting. That is, ωa = N × 360 ° / T, and the N is “2”, for example.

  In step S2, the compression top dead center is determined. Here, the pulsar pickup 7 outputs rising and falling pulses at a crank angle that determines the ignition timing before compression top dead center and at a crank angle before overlap top dead center between the exhaust stroke and the intake stroke. However, as shown in FIG. 3, the crank angular velocity ω at the crank angle before the compression top dead center is smaller than the average crank angular velocity ωa, and the crank angular velocity ω before the overlap top dead center is equal to the crank angular velocity. Since it is larger than the average value ωa, it is easy to determine whether the pulse output from the pulsar pickup 7 is before the compression top dead center or before the overlap top dead center.

In step S3, the angular velocity fluctuation amount Δω of the crank angle, which is a factor that changes depending on the operating state of the internal combustion engine EA, is calculated. The angular velocity fluctuation amount Δω is calculated as (Δω = ωa−ωtdc). Moreover, in order to eliminate the influence of the rotational speed Ne of the internal combustion engine EA, the angular speed fluctuation amount Δω is set to the angular speed fluctuation amount ωwot when the rotational speed Ne is constant and in a full load state (maximum throttle opening state). A dimensionless value ω ^* (= ωtdc / ωwot) that has become dimensionless by dividing is calculated. In the next step S4, the dimensionless value ω ^* is smoothed.

In step S5, the ignition timing is searched according to a predetermined map. That is, a map shown in FIG. 5 is prepared in advance and stored in the memory 10 based on the dimensionless value ω ^* and the rotational speed Ne of the internal combustion engine EA. In step S5, the dimensionless value is determined according to the map. ω ^* and on the basis of the rotation speed Ne of the internal combustion engine EA, to find the ignition timing.

In the next step S6, various corrections such as acceleration correction and temperature correction are performed on the ignition timing obtained in step S5. Thus, the acceleration correction is correction based on the cycle change of the angular velocity fluctuation amount Δω, and when the current angular velocity fluctuation amount is Δω _n and the previous angular velocity fluctuation amount is Δω _n−1 , the correction value k1 is k1 = It is obtained as f (Δω _n −Δω _n-1 ). The temperature correction is a correction based on the intake air temperature and the engine temperature (or cooling water temperature), and a correction value k2 is obtained as k2 = f {intake air temperature, engine temperature (or cooling water temperature)}.

  In step S7, the ignition timing corrected in step S6 is output, and the spark plug 3 is ignited at the ignition timing.

  As described above, by determining the ignition timing based on the angular velocity fluctuation amount Δω and the rotational speed Ne of the internal combustion engine EA, it is possible to control the operation of the internal combustion engine EA without calculating the intake air amount. However, if the angular velocity fluctuation amount Δω is used, the intake air amount can be easily estimated, and the estimation method will be described below.

The torque fluctuation ΔN of the internal combustion engine EA is the difference between the net torque and the running resistance torque of the internal combustion engine EA, the output torque of the internal combustion engine EA due to the cylinder pressure is N _{cylindere.work,} and the friction resistance torque of the internal combustion engine EA is N _{When the friction} is set to N and the running resistance torque is N _load , the relationship with the equivalent moment of inertia I of the crankshaft 4 can be expressed by the following equation of motion.

ΔN = (N _{cylindere.work} −N _friction ) −N _load = I · (dω / dt) (1)
Here, the pressure in the _cylinder is P _cylinder , the cylinder inner diameter is B, the gas mass in the combustion chamber is M, the gas constant is R, the gas absolute temperature is T, the cylinder volume is V, and the effective radius for torque calculation is r. Occasionally, a _{N cylindere.work = P cylinder · (π} / 4) B 2 · r ... (2) P cylinder = M · R · T / V ... (3), the frictional resistance torque N _friction and running resistance torque Substituting the above equations (2) and (3) into the above equation (1) ignoring N _load , dω / dt = (1 / I) · (M · R · T / V) · (π / 4) B ² · r (4)

  As shown in FIG. 6, the crank angular velocity ω is decelerated before the compression top dead center, and the deceleration slope (dω / dt) before the compression top dead center is 2 points before the compression top dead center. When the time between two points is Δτ, and the average crank angular velocity, that is, the angular velocity fluctuation amount from the rotational speed Ne of the internal combustion engine EA is Δω, dω / dt = Δω / Δτ (5)

Thus, the angular velocity fluctuation amount Δω before the compression top dead center is calculated as (Δω = Ne−ωtdc) based on the average angular velocity ωtdc obtained from the pulse output from the pulser pickup 7 that detects the reluctator 6. The above equation (4) is expressed as follows: Δω / Δτ = M · T · (1 / I) · (R / V) · (π / 4) B ² · r (6) Here, M is the amount of air taken into the combustion chamber, and {(1 / I) · (R / V) · (π / 4) B ² · r} is constant, and the rotational speed of the internal combustion engine EA Assuming that Δτ is constant when Ne is the same, it is Δω∝M · T, and when suction temperature T is constant, Δω∝M, which is output from the pulsar pickup 7 that detects the relaxor 6. The intake air amount can be easily estimated from the angular velocity fluctuation amount Δω obtained based on the pulse.

  Next, the operation of the first embodiment will be described. As the crankshaft 4 rotates, the front end portion 6a and the rear end portion 6b along the rotational direction 13 of one reluctator 6 provided on the crankshaft 4 are detected. On the basis of the rising and falling pulse intervals output from the pulser pickup 7, the calculating means 11 in the CPU 9A of the electronic control unit 8A calculates the rotational speed Ne of the internal combustion engine EA and the angular speed fluctuation amount Δω of the crank angle. Based on the calculation result of the calculation means 11, the processing means 12A controls the operating state of the internal combustion engine EA so as to determine the ignition timing of the spark plug 3 by the control map using the angular velocity fluctuation amount Δω as a variable. Reduce the number of parts required to detect factors that change according to the operating state of the engine EA, and perform computations. It is possible to improve combustion by Ryakuka.

  Moreover, since the reluctator 6 is provided on the crankshaft 4 at the crank angle before the compression top dead center, the angular velocity fluctuation amount Δω is obtained at the crank angle before the compression top dead center, and the angular velocity fluctuation amount Δω is relatively large. It is possible to obtain an accurate angular velocity fluctuation amount Δω by obtaining the angular velocity fluctuation amount at the portion.

  Further, a reluctor 6 for detecting the front end portion 6a and the rear end portion 6b by the pulsar pickup 7 is provided in the rotor 5 of the generator ACG in order to detect the reference ignition timing of the internal combustion engine EA. Since it is used for the detection of the reference ignition timing and the calculation of the angular velocity fluctuation amount Δω of the crank angle, it is possible to control the operation of the internal combustion engine EA with only one reluctor 6 of the generator ACG. Thus, for example, an inexpensive generator for an internal combustion engine that does not control the ignition timing or the fuel injection amount only by detecting only the reference ignition timing can be used. Thus, it is easy to reduce the cost of the internal combustion engine EA that performs operation control.

  FIG. 7 shows a second embodiment of the present invention. The parts corresponding to the first embodiment are indicated by the same reference numerals, and the detailed description is omitted.

  The internal combustion engine EB includes an ignition plug 3 and a variable valve mechanism 14 that changes operating characteristics in accordance with the operating state. The air purified by the air cleaner 15 is supplied to the internal combustion engine EB. A throttle valve 17 is rotatably disposed in the middle of the intake pipe 16 to be guided, and fuel is supplied into the intake pipe 16 by a fuel injection valve 18 on the downstream side of the throttle valve 17. An exhaust gas recirculation device 20 is provided between the intake pipe 16 on the downstream side of the throttle valve 17 and the exhaust pipe 19 that guides the exhaust gas discharged from the internal combustion engine EB.

  In response to the rotation of the crankshaft 4 of the internal combustion engine EB, a pulse signal is output from the pulsar pickup 7 that detects a single reluctor as in the first embodiment. Is input to the electronic control unit 8B. The electronic control unit 8B includes a CPU 9B and a memory 10B composed of a RAM, a ROM, and the like. The CPU 9B is configured to generate an internal combustion engine EB based on the rising and falling pulse intervals output from the pulser pickup 7. The function of the calculation means 11 for calculating the rotational speed and the angular velocity fluctuation amount of the crank angle, the ignition timing of the spark plug 3, the operating characteristics of the variable valve mechanism 14, the fuel injection valve based on the calculation result of the calculation means 11 18 and the processing unit 12B for controlling the exhaust gas recirculation start timing and the exhaust gas recirculation amount by the exhaust gas recirculation device 20.

  That is, the ignition timing control of the spark plug 3 in the first embodiment is performed on the basis of a control map in which the angular velocity variation Δω of the crank angle calculated by the calculation means 11 of the CPU 9B based on the output signal of the pulser pickup 7 is a variable. In addition, the operation characteristic control of the variable valve mechanism 15, the injection start timing and the injection amount control of the fuel injection valve 18, and the exhaust gas recirculation start timing and the exhaust gas recirculation amount control by the exhaust gas recirculation device 20 are executed. In other words, it is possible to reduce the number of parts necessary for detecting a factor that changes in accordance with the operating state of the internal combustion engine EB, and to simplify combustion and improve combustion.

  Although the embodiments of the present invention have been described above, the present invention is not limited to the above-described embodiments, and various design changes can be made without departing from the present invention described in the claims. It is.

  For example, in the above-described embodiment, the case where one reluctor 6 is provided on the crankshaft 4 has been described. However, a plurality of reluctors may be provided on the crankshaft 4, and in that case, one of the plurality of reluctors may be provided. The angular velocity fluctuation amount Δω may be calculated using this.

It is a figure which shows the whole structure of the operation control apparatus of the internal combustion engine of 1st Example. It is a figure which shows the relationship of the output timing of a reluctor and a pulsar pickup. It is a figure which shows the relationship of the stroke of an internal combustion engine, a reluctor, and crank angular velocity. It is a flowchart which shows the control procedure by a control unit. It is a figure which shows the control map which determines ignition timing. It is a figure which shows the change of the crank angular velocity in the compression top dead center vicinity. It is a figure which shows the whole structure of the operation control apparatus of the internal combustion engine of 2nd Example.

Explanation of symbols

4 ... Crankshaft 5 ... Rotor 6 ... Retractor 6a ... Front end 6b ... Rear end 7 ... Pulsar pickup 11 ... Calculation means ACG ... Generator EB ...・ Internal combustion engine

Claims (3)

  The operation state of the internal combustion engine (EA, EB) is controlled by a control map having a variable that changes according to the operation state of the internal combustion engine (EA, EB) as a variable. In the control device, of at least one of the relucters (6) provided on the crankshaft (4), the front end (6a) and the rear end (in the direction of rotation of the crankshaft (4) of one reluctator (6) ( 6b) is detected according to the rotation of the crankshaft (4) and outputs a pulse, and the pulser pickup (7) is detected by detecting the front end (6a) and the rear end (6b). And an arithmetic means (11) for calculating an angular velocity fluctuation amount of the crank angle based on an interval of pulses output from the internal combustion engine. Operation control device.   A reluctor (6) for detecting the front end (6a) and the rear end (6b) by the pulsar pickup (7) is provided on the crankshaft (4) at a crank angle before compression top dead center. 2. The operation control apparatus for an internal combustion engine according to claim 1, wherein   A reluctator (6) for detecting the front end (6a) and the rear end (6b) with the pulsar pickup (7) generates a generator (ACG) for detecting a reference ignition timing of the internal combustion engine (EA, EB). The rotor (5) of the internal combustion engine according to claim 1, wherein the reluctator (6) is used for detecting the reference ignition timing and calculating an angular velocity fluctuation amount of the crank angle. Operation control device.

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