JPH08284734A - Engine speed measuring device of spark ignition type internal combustion engine - Google Patents

Abstract

PURPOSE: To measure an accurate engine speed of an engine from an ignition signal by restraining the effect of a timing retard, etc. CONSTITUTION: The device in the title is provided with an ignition timing calculation means 50 for calculating the advance angle or delay angle of an ignition timing following the running state of an engine, a drive means 51 for sending out an ignition signal to an ignition means 52 following this ignition timing, the rotation speed of the engine calculation means 53 for calculating the rotation speed of the engine following the period of the ignition signal, a memory means 54 for renewing in order the calculated rotation speed of the engine and an ignition timing change judging means 55 for judging the change of the ignition timing when the ignition timing is compared with a prescribed value and the ignition timing exceeds the prescribed value. When this judging result is the change of the ignition timing, a previous rotation speed of the engine stored in the memory means is set as a present rotation speed of the engine, while when it is not so, a change over means 56 for setting the present rotation speed of the engine is provided.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an improvement in a device for measuring the rotational speed of a spark ignition type internal combustion engine based on an ignition signal.

[0002]

2. Description of the Related Art In vehicles such as automobiles, it is known that the output of a spark ignition type internal combustion engine (hereinafter simply referred to as "engine") is controlled by an automatic transmission, and a controller provided in the engine and an automatic transmission are used. A controller provided in the machine is connected by communication means or the like to perform gear shifting according to the engine speed, throttle opening or vehicle speed, while temporarily reducing the engine output during gear shifting of the automatic transmission, An integrated control device for an engine and an automatic transmission that suppresses an impact generated during a gear shift is known, and the applicant of the present application has proposed it as Japanese Patent Laid-Open No. 2-38748.

Such a controller is provided with an engine speed measuring device for calculating the engine speed from the cycle of the engine ignition signal in order to perform gear shift control and various controls based on the engine speed.

[0004]

By the way, in some spark ignition type internal combustion engines, when knocking is detected, there is one that suppresses knocking by performing timing retard for temporarily delaying the ignition timing. The ignition timing may be changed for the purpose of not increasing or decreasing.

However, in the above-mentioned conventional engine speed measuring device, the engine speed is calculated from the cycle of the engine ignition signal, so that there is a change in the ignition timing not intended to increase or decrease the engine speed as described above. Even in the case of the above, there is a problem that the measured engine speed fluctuates, and an accurate engine speed may not be obtained.

Therefore, the present invention has been made in view of the above problems, and spark ignition capable of accurately measuring the engine speed even when the ignition timing is changed without the purpose of increasing or decreasing the engine speed. An object of the present invention is to provide a rotational speed measuring device for a rotary internal combustion engine.

[0007]

As shown in FIG. 8, the first invention is an ignition timing calculation means 50 for calculating the advance or retard of the ignition timing according to the operating state of the engine, and the ignition timing calculation means 50. Drive means 51 for sending an ignition signal to the ignition means 52 in accordance with the above, an engine speed calculating means 53 for calculating the engine speed according to the cycle of the ignition signal, and the calculated engine speed is sequentially updated. Storage means 54
And an ignition timing variation determining means 55 for comparing the ignition timing with a predetermined value to determine variation in the ignition timing when the ignition timing exceeds the predetermined value, and when the determination result is variation in the ignition timing. Includes a switching means 56 for setting the previous engine speed stored in the storage means as the current engine speed, and otherwise setting the current engine speed.

According to a second aspect of the present invention, in the first aspect of the invention, when the determination result of the ignition timing variation determination means is the variation of the ignition timing, the switching means calculates the engine speed calculation means. To stop.

A third invention is the first or second invention.
In the invention, the ignition timing fluctuation determining means compares a predetermined value preset according to the engine speed with the ignition timing, and determines the fluctuation of the ignition timing when the ignition timing exceeds a predetermined value. .

Further, in the fourth aspect of the present invention, as shown in FIG. 9, an ignition timing calculating means 50 for calculating the advance angle or the retard angle of the ignition timing in accordance with the operating state of the engine, and an ignition means 52 in accordance with the ignition timing. A drive unit 51 for sending an ignition signal, an ignition timing variation amount calculation unit 57 for computing the variation amount of the ignition timing, a correction unit 58 for correcting the cycle of the ignition signal according to the ignition timing variation amount, and And an engine speed calculator 53 for calculating the engine speed according to the corrected cycle of the ignition signal.

[0011]

Therefore, according to the first aspect of the invention, the ignition signal is sent to the ignition means at the ignition timing corresponding to the operating state of the engine to operate the engine, and the engine speed is calculated according to the cycle of the ignition signal. The means calculates the engine speed, and stores and updates the current calculation result instead of the previous calculation result stored in the storage means. If the variation in the ignition timing is within a predetermined value, the current calculation is performed. The result is output as the engine speed, but when the ignition timing fluctuates beyond a predetermined value, the previous engine speed stored in the storage means by the switching means is set as the current engine speed, The engine speed can be accurately measured regardless of variations in ignition timing that are not intended to increase or decrease the engine speed by knocking suppression control or the like.

According to a second aspect of the present invention, the switching means stops the calculation of the engine speed calculating means while the determination result of the ignition timing variation determining means determines that the ignition timing is varying. The previous engine speed stored in is not updated, this previous value is used as the current engine speed, and the engine speed caused by fluctuations in the ignition timing is not intended to increase or decrease the engine speed by knocking suppression control, etc. Accurate engine speed can be measured by preventing erroneous measurement of the number.

According to a third aspect of the present invention, the ignition timing fluctuation determining means compares a predetermined value preset according to the engine speed with the ignition timing, and when the ignition timing exceeds a predetermined value. Since the variation of the ignition timing is determined, the variation of the ignition timing can be reliably determined according to the ignition timing that changes according to the engine speed.

According to a fourth aspect of the present invention, an ignition signal is sent to the ignition means at an ignition timing corresponding to the operating state of the engine to operate the engine, and the ignition is corrected according to the variation of the ignition timing. Since the engine speed calculating means calculates the engine speed from the signal cycle, the engine speed is always accurately measured regardless of variations in the ignition timing, which is not intended to increase or decrease the speed by knocking suppression control or the like. be able to.

[0015]

Embodiments of the present invention will be described below with reference to the accompanying drawings.

As shown in FIG. 1, a spark ignition type engine 1 is provided with an engine controller 3 for calculating and controlling a fuel injection amount and an ignition timing, and a throttle opening sensor, a crank angle sensor, an air flow meter (not shown). The fuel injection amount and the ignition timing are determined based on the detection signals of the throttle opening, the engine speed, and the intake air amount, etc., and a command signal is sent to a fuel injection valve and an ignition device (not shown).

The engine 1 is connected to an automatic transmission 2, the output of the engine 1 is transmitted to wheels (not shown) through the automatic transmission 2, and the automatic transmission 2 calculates a shift position and a shift timing by a shift control controller 4. Controlled.

The shift control controller 4 is connected to the engine control controller 3 through a communication means. In this communication, for example, when the shift control controller 4 starts upshifting or downshifting, the engine control controller 3 is requested to reduce its output. By transmitting a signal, the engine control controller 3 changes the fuel injection amount or the ignition timing to shift the automatic transmission 2 in a state in which the torque of the engine 1 is reduced, thereby suppressing the impact generated during the shift. This is to perform so-called integrated control of an engine and an automatic transmission, which control each other by communication of the controller.

Here, an ignition signal from an ignition device (not shown) of the engine 1 is input to the shift control controller 4, and the rotation speed of the engine 1 is measured based on the cycle of this ignition signal and measured. The shift control of the automatic transmission 2 is performed based on the engine speed.

An example of the engine speed measurement operation performed by the shift control controller 4 is shown in the flowchart of FIG.
An example of the ignition timing communication control performed by the engine controller 3 is shown in the flowchart of FIG. 3, and will be described in detail below with reference to these flowcharts.

The flowchart of FIG. 2 executed by the shift control controller 4 is executed by interrupt processing in response to the generation of an ignition signal input from the engine 1. First, in step S1, ignition from the ignition device of the engine 1 is performed. The time when the signal is input is the interrupt time NewTi
Store as me. The interrupt time is measured in units of μsec.

Then, in step S2, it is determined whether or not an ignition timing fluctuation signal, which will be described later, indicating that the ignition timing has exceeded a predetermined value X (deg) is input from the engine controller 3 via the communication means. When the ignition timing fluctuation signal is input, the engine speed K is not calculated and the process proceeds to step S7.
In step S3, engine speed calculation processing is performed.

Step S3 is the current interrupt time NewT
Cycle T based on the difference between time and the previous interrupt time OldTime
(Μsec) is calculated, and in step S4, the engine speed K (rpm) is calculated from the cycle T by the following equation.

[0024] ^{K = 60 × 10 6/3} × T where the constant 3 shows the case of a four-cycle six-cylinder engine, is a constant when the ignition signal is generated for each rotation of 120 degrees of the crank shaft.

In step S5, the difference between the engine speed K calculated this time and the previous value KOLD is calculated as the fluctuation amount de of the speed.
In addition to storing it as ltaK, the engine speed K of this time is stored as the previous value KOLD in step S6 to prepare for the next measurement. Further, in step S7, the interrupt time NewTime of this time is compared with the previous interrupt time OldTime.
Then, the process ends in preparation for the next measurement.

On the other hand, in the engine controller 3,
The flowchart shown in FIG. 3 is executed every predetermined time,
First, in step S20, the ignition timing A (deg (BTDC)) is calculated based on the operating state of the engine 1, for example, the engine speed from a crank angle sensor (not shown).
Is calculated. The ignition timing A is calculated as an angle before the top dead center of the crankshaft.

In step S21, the difference between the ignition timing AOld calculated last time and the ignition timing A calculated this time is calculated as the ignition timing fluctuation amount DA, and in step S22, the absolute value of this ignition timing fluctuation amount is a preset value X. It is determined whether or not (deg) or more. The predetermined value X is a value set according to the engine speed.

If the ignition timing fluctuation amount DA is greater than or equal to the predetermined value X, the process proceeds to step S23, and the ignition timing fluctuation signal is sent to the shift control controller 4 via the communication means. The fact that there is no change in the timing is sent to the shift control controller 4 and the process ends.

By performing the above control in the shift control controller 4 and the engine control controller 3, respectively, the shift control controller 4 causes the interrupt time NewTime.
And the OldTime, the engine speed K of the engine 1 is calculated based on the cycle T of the ignition signal. The engine control controller 3 changes the ignition timing A by knocking suppression control or the like, and the ignition timing fluctuation amount DA is set to a predetermined value. When the value is equal to or greater than the value X, the ignition timing fluctuation signal is sent to the shift control controller 4 via the communication means, and the shift control controller 4 performs the steps S3 to S6 while the ignition timing fluctuation signal is sent. Since the engine speed calculation process of is prohibited, the previous engine speed can be set as the current engine, and the fluctuation of the engine speed K caused by the change of the ignition timing A which is not intended to increase or decrease the engine speed. Therefore, the engine speed can be accurately measured based on the cycle of the ignition signal.

The flow charts shown in FIGS. 4 and 5 show the state of the integrated control of the output reduction operation during the shift performed by the shift control controller 4 and the engine control controller 3 at predetermined time intervals.

The shift control controller 4 operates in step S1.
At 0, it is determined whether or not the automatic transmission 2 is in the process of shifting. If the automatic transmission 2 is in the process of shifting, it is determined at step S11 whether or not the DFLAFG requesting the output reduction of the engine 1 is set to 1.

If DFLAG is 1 in step S11, the engine speed fluctuation amount d obtained in step S5 is calculated.
In step S12, it is determined whether the value of eltaK is positive. If the value is positive, it is determined that the gear shift has ended, and in step S13, DFLA
While resetting to G = 0 and ending the processing, if not, the process proceeds to step S14, and it is determined whether the variation amount deltaK of the engine speed K is smaller than a predetermined value, in this case, −30 rpm.

If deltaK is less than the predetermined value, it is determined that the gear shift has started and the engine speed has started to decrease, and in step S15 DFLAG = 1 is set to reduce the output of the engine 1 and communication is performed. The engine controller 3 is requested to reduce the output of the engine 1 via the means.

In step S30 of FIG. 5, the engine controller 3 determines whether or not DFLAG = 1. If DFLAG is 1, output reduction processing is performed in step S31, for example, reduction of fuel injection amount or timing retard. By temporarily reducing the engine output by performing the above, it is possible to suppress the impact generated in the automatic transmission 2 during shifting.

FIGS. 6 and 7 are flow charts showing the second embodiment. Based on the ignition timing variation DA calculated by the engine controller 3 in the first embodiment, the shift control controller 4 causes the engine speed K to change. Correction calculation is performed, and the other points are the same as those in the first embodiment.

In the engine controller 3, the flowchart shown in FIG. 6 is executed at predetermined time intervals.
In step S40, the ignition timing A (deg (BTDC)) is calculated based on the operating state of the engine 1, for example, the engine speed from a crank angle sensor (not shown).

In step S41, the time obtained by dividing the difference between the previously calculated ignition timing AOld and the currently calculated ignition timing A by the engine speed is calculated as the ignition timing fluctuation amount Z (μsec). In step S42, this ignition timing is calculated. Variation Z
Is sent to the shift control controller 4 via the communication means, and the process is terminated.

On the other hand, the flowchart of FIG. 7 executed by the shift control controller 4 is executed by interrupt processing in response to the generation of an ignition signal input from the engine 1. First, in step S50, the ignition device of the engine 1 is started. Interruption time Ne when the ignition signal is input from
Detect as wTime.

Then, in step S51, the ignition timing fluctuation amount Z from the engine controller 3 is read via the communication means.

Step S52 is the interrupt time New this time.
A value obtained by adding the ignition timing fluctuation amount Z to Time and correcting the cycle of the ignition signal according to the fluctuation amount of the ignition timing is stored as the interrupt time NewTime, and the current interrupt time NewTime and the previous value are stored in step S53. The cycle T (μsec) is calculated from the difference between the OldTimes, and the engine speed K is calculated from the cycle T in step S54 as in step S4.
(Rpm) is calculated.

In step S55, the difference between the engine speed K calculated this time and the previous value KOLD is calculated as the fluctuation amount d of the speed.
In step S56, the engine speed K of this time is stored as the previous value KOLD to prepare for the next measurement, and in step S57, the interrupt time NewTime of this time is compared with the previous interrupt time OldT.
It is stored as "ime" and the process ends in preparation for the next measurement.

In this case as well, in the same manner as above, the shift control controller 4 causes the interruption time NewTime and OldTime.
Although the engine speed K of the engine 1 is calculated based on the cycle T of the ignition signal obtained from the difference of e, when the engine control controller 3 changes the ignition timing A by knocking suppression control or the like, the engine control controller 3 changes the ignition timing A according to the ignition timing fluctuation amount Z. Interrupt time NewTime
Is corrected, fluctuations in the engine speed K due to changes in the ignition timing A that are not intended to increase or decrease the engine speed can be suppressed, and accurate measurement of the engine speed can be performed. The shift control operation as shown in FIG. 4 can be reliably performed based on the accurate engine speed.

[0043]

As described above, according to the first aspect of the invention, the engine speed is calculated according to the cycle of the ignition signal, and the storage means updates the current calculation result instead of the previous calculation result. If the ignition timing fluctuation amount is within a predetermined value, the current engine speed is output, but if the ignition timing fluctuates beyond the predetermined value, the previous engine speed stored in the storage means by the switching means is changed. Since it is set as the current engine speed, it is possible to accurately measure the engine speed regardless of changes in the ignition timing, which is not intended to increase or decrease the speed by knocking suppression control, etc., and improve the measurement accuracy. It will be possible.

According to a second aspect of the present invention, the switching means stops the calculation of the engine speed calculation means when the determination result of the ignition timing variation determination means is the variation of the ignition timing. The previous engine speed stored in is not updated, but this previous value is used as the current engine speed, and the engine speed is caused by fluctuations in ignition timing that are not intended to increase or decrease the engine speed such as knocking suppression control. It is possible to prevent erroneous measurement of the number and improve the measurement accuracy of the engine speed.

According to a third aspect of the present invention, the ignition timing fluctuation determining means compares the ignition timing with a predetermined value preset according to the engine speed, and when the ignition timing exceeds a predetermined value. Since the fluctuation of the ignition timing is determined, it is possible to reliably determine the fluctuation of the ignition timing according to the ignition timing that changes according to the engine speed and improve the measurement accuracy of the engine speed.

In a fourth aspect of the present invention, an ignition signal is sent to the ignition means at an ignition timing corresponding to the operating state of the engine to operate the engine, and the ignition is corrected according to the variation of the ignition timing. Since the engine speed calculation means calculates the engine speed from the signal cycle, it is necessary to constantly measure the accurate engine speed regardless of variations in the ignition timing, which is not intended to increase or decrease the speed by knocking suppression control or the like. The measurement accuracy can be improved.

[Brief description of drawings]

FIG. 1 is a block diagram showing an embodiment of the present invention.

FIG. 2 is a flowchart showing an example of a measurement operation performed by the shift control controller.

FIG. 3 is a flowchart showing an example of ignition timing calculation control performed by an engine controller.

FIG. 4 is a flowchart showing an example of shift control performed by a shift control controller.

FIG. 5 is a flowchart showing an example of torque control similarly performed by the engine controller.

FIG. 6 is a flowchart showing another embodiment and an example of ignition timing calculation control performed by the engine controller.

FIG. 7 is a flow chart showing another example of an operation of measuring the engine speed performed by the shift control controller.

FIG. 8 is a claim correspondence diagram corresponding to any one of the first to third inventions.

FIG. 9 is a claim correspondence diagram corresponding to the fourth invention.

[Explanation of symbols]

 1 Engine 2 Automatic Transmission 3 Engine Control Controller 4 Shift Control Controller 50 Ignition Timing Calculation Means 51 Drive Means 52 Ignition Means 53 Engine Rotation Speed Calculation Means 54 Storage Means 55 Ignition Timing Fluctuation Judgment Means 56 Switching Means 57 Ignition Timing Variation Amount Means 58 Correction means

Claims (4)

[Claims] 1. An ignition timing calculation means for calculating an advance angle or a retard angle of ignition timing according to an operating state of an engine, a driving means for sending an ignition signal to the ignition means according to the ignition timing, and the ignition signal. Engine speed calculation means for calculating the engine speed according to the cycle, storage means for sequentially updating the calculated engine speed, the ignition timing is compared with a predetermined value, and the ignition timing is a predetermined value. If the ignition timing fluctuation judging means judges the fluctuation of the ignition timing when it exceeds, the previous engine speed stored in the storage means is set to the current engine speed if the judgment result is the fluctuation of the ignition timing. A spark ignition internal-combustion-engine rotational speed measuring device comprising: a switching means for setting the present engine rotational speed if it is not set. 2. The switching means stops the calculation of the engine speed calculation means when the determination result of the ignition timing variation determination means is the variation of the ignition timing. A rotational speed measuring device for a spark ignition type internal combustion engine as described. 3. The ignition timing variation determining means compares a predetermined value preset according to the engine speed with the ignition timing to determine a variation in the ignition timing when the ignition timing exceeds a predetermined value. The rotational speed measuring device for a spark ignition type internal combustion engine according to claim 1 or 2, wherein: 4. An ignition timing calculating means for calculating an advance or a retard of ignition timing according to an operating state of an engine, a driving means for sending an ignition signal to the ignition means according to the ignition timing, and the ignition timing. Variation amount calculation means for calculating the variation amount of the ignition timing, correction means for correcting the cycle of the ignition signal according to the variation amount of the ignition timing, and engine speed according to the corrected cycle of the ignition signal. An engine speed measuring device for calculating the engine speed of a spark ignition type internal combustion engine.