JPS60243370A - Signal processing device for electronic control system for vehicle - Google Patents

Abstract

PURPOSE:To permit to determine the frequency of waveform shaping signal with high accuracy by a method wherein the masking frequency with respect to noise is changed in accordance with a primary coil voltage in the device in which the noise in the waveform shaped signal of the primary coil voltage generated in an ignition coil is being masked. CONSTITUTION:An ignition circuit 10 is equipped with a conduction control circuit 11, generating an ignition control signal necessary for the starting and finishing of conduction for the primary coil 21 of the ignition coil 20, and a transistor 12. In this case, a comparating means, comparing a preceeding waveform shaping signal with following waveform shaping signal and masking the following waveform shaping signal when the generating period of time of the following waveform shaping signal is shorter than a predetermined period of time, is equipped in a micro-computer 50, inputting the output signal of a waveform shaping circuit 40 shaping the waveform of a primary coil voltage Vi generated in the ignition coil 20 in order to utilize for the various kinds of control of the vehicle. On the other hand, a setting means, setting an elapsed time from the level change of the preceeding waveform shaping signal after releasing masking to the level change of the following waveform shaping signal as the period of following waveform shaping signal, is equipped in the device.

Description

[Detailed Description of the Invention] [Field of Industrial Application] The present invention relates to an electronic control system for controlling the running speed of a vehicle, controlling the ignition timing of an internal combustion engine for a vehicle, controlling fuel injection, etc., and particularly relates to this electronic control system. The primary winding voltage of the ignition coil of an internal combustion engine is sequentially waveform-shaped and generated as a waveform-shaped signal, and these waveform-shaped signals are used for various controls such as the above-mentioned traveling speed control, ignition timing control, and fuel injection control. The present invention relates to a signal processing device for a vehicle electronic control system that processes signals as necessary for a vehicle.

[Prior art]

Conventionally, in this type of signal processing device, for example, a monostable multi-bi break is adopted, and the output signal generated from this monostable multi-bi break is used to adjust the waveform shaping signal to each waveform shaping signal during the period of each waveform shaping signal mentioned above. A signal that masks mixed noise and has falling and rising edges corresponding to the rise of the secondary winding voltage representing the ignition timing and the falling of the secondary winding voltage representing the timing of starting energization of the ignition coil, respectively. There is a device that processes each of the waveform shaping signals.

However, in such a configuration, the signal width of the output signal from the monostable multi-bi break is always constant regardless of the periodic change in the secondary winding voltage. Depending on the length of the voltage cycle, the above-mentioned noise may not be reliably masked by the output signal from the monostable multi-high break, and as a result, errors may occur in the processing contents corresponding to each of the above-mentioned waveform shaping signals. There was a problem that occurred.

(Object of the Invention) In contrast, the present inventors have discovered that due to the rotational inertia of the internal combustion engine, the period of the primary winding voltage of the ignition coil is shorter than the period of the primary winding voltage of the ignition coil that precedes this primary winding voltage. Approximately 1/3~
Provided is a signal processing device for a vehicle electronic control system that changes the mask period for the above-mentioned noise in accordance with the period change of the primary winding voltage of the ignition coil, focusing on the fact that the coefficient is higher than 2/3. This is what I am trying to do.

(Structure of the Invention) In achieving the above object, the structural features of the present invention are as follows:
As illustrated in FIG. 1, it is equipped with a waveform shaping means 2 that sequentially shapes the waveform of the primary winding voltage generated from the ignition coil 1 in the ignition period of the vehicle internal combustion engine and generates it as a waveform shaping signal. In a signal processing device that processes a signal as a signal necessary for control by a vehicle electronic control system, a preceding waveform-shaped signal and a subsequent waveform-shaped signal successively generated from the waveform shaping means 2 are compared and the following waveform-shaped signal is processed. Comparison in which the subsequent waveform-shaped signal is masked when the generation time of the waveform-shaped signal is shorter than a predetermined time set within about 1/3 to 2/3 of the period of the preceding waveform-shaped signal, and the mask is canceled when it becomes longer. means 3, and when there is a level change in the trailing waveform shaped signal under mask cancellation by the comparison means 3, the trailing waveform shaped signal is determined from a level change in the preceding waveform shaping signal under mask cancellation by the comparison means 3; A setting means 4 is provided for setting the elapsed time until the level changes as the period of the trailing waveform shaping signal, and the period set by the setting means 4 is set as the period of the signal necessary for control by the electronic control system. It's because I did it.

〔Effect of the invention〕

Therefore, by configuring the present invention in this way, the comparing means 3 masks the trailing waveform shaping signal when the generation time of the trailing waveform shaping signal is less than or equal to the predetermined time; When the signal generation time becomes longer than the predetermined time, the mask is released, and the setting means 4 determines the level of the preceding waveform-shaped signal from the level change of the preceding waveform-shaped signal under the mask previously made by the comparison means 3. Since the elapsed time until the level change is set as the period of the trailing waveform shaping signal, various noises mixed in the trailing waveform shaping signal immediately after the internal combustion engine is ignited can be eliminated from each of the preceding and trailing waveform shaping signals. Irrespective of changes in the period, the period of the trailing waveform-shaped signal, that is, the period of the waveform-shaped signal sequentially output from the waveform shaping means 3, can always be accurately determined in a masked state.

〔Example〕

Hereinafter, one embodiment of the present invention will be explained with reference to the drawings.
In the figure, reference numerals 10 and 20 respectively indicate an ignition circuit and an ignition coil of a vehicle internal combustion engine. Ignition circuit 1
0 is composed of an energization control circuit 11 and a transistor 12, and the energization control circuit 11 starts energization to the primary winding 21 of the ignition coil 20 by a known control method in relation to the operation of the internal combustion engine. and generates the energization start signal and energization end signal necessary for termination. The transistor 12 becomes conductive in response to an energization start signal from the energization control circuit 11, and becomes non-conductive in response to an energization end signal from the energization control circuit 11.

The primary winding 21 of the ignition coil 20 is energized from the positive terminal +B1 of the DC power supply in response to the conduction of the transistor 12,
This energization of the secondary winding 21 is terminated in response to the non-conduction of the transistor 12. In other words, the common terminal between the collector of the transistor 12 and the primary winding 21 of the ignition coil 20 has a period Ti (i-1, 2,
) with the primary winding voltage Vi (i=1.2.
) lives there. In such a case, this negative winding voltage Vi
The rising edge ai (corresponding to the ignition timing of the internal combustion engine) is determined by the non-conduction of the transistor 12, and the falling edge bi (corresponding to the timing of starting energization of the ignition coil 20) of the second winding voltage Vi is determined by the non-conduction of the transistor 12. Defined by continuity. Note that the secondary winding 22 of the ignition coil 20 generates a high voltage in response to the end of energization of the primary winding 21 and applies it to the distributor 30 of the internal combustion engine.

The waveform shaping circuit 40 has a transistor 41, whose base is connected to the positive terminal +131 of the DC power supply via a resistor 41a and grounded via a resistor 41b. Further, the emitter of this transistor 4I is connected to the collector of the transistor 12 via a resistor 41C, and the emitter of the transistor 4I is connected to the collector of the transistor 12 through a resistor 41C.
1d, is grounded via a capacitor 41e and a resistor 41f.

Thus, the transistor 41 connects the positive side terminal +81 of the DC power source to both resistors 41a at its base.

41b, and both resistors 41c, 41f,
It receives the primary winding voltage Vi through the capacitor 4.1e and the diode 41d, becomes conductive in response to the rising edge ai of the secondary winding voltage Vi, and conducts in response to the falling edge bi of the same primary winding voltage Vi. It becomes non-conductive. In addition, capacitor 4.
1e lowers the primary winding voltage Vi from the transistor 12 from its rising edge ai to its falling edge bi under the discharging effect in cooperation with the resistor 41C.

The transistor 42 has its emitter grounded, its base connected to the collector of the transistor 41 via a resistor 42a, and the collector of this transistor 42 connected to the positive terminal 1B2 of the DC power supply via a resistor 42b. ing. Thus, the transistor 42 becomes conductive under the control of the resistor 42a which responds to the conduction of the transistor 41, becomes non-conductive in response to the non-conduction of the transistor 41, and the transistor 42 becomes conductive as shown in FIG. A waveform shaped signal Si (having a period T1) is generated. In such a case, the falling edge Ai of the waveform shaping signal Si is the rising edge of the primary winding 21.
Corresponding to the second ai, the rising edge Bi of the waveform shaping signal S1
corresponds to the fall bi of the primary winding voltage Vi. Also,
Due to the rotational inertia of the internal combustion engine, the period of the waveform shaping signal Si+1 is ``f' i +l≧Ti/2, and the primary winding voltage Vi is obsolete due to the release of energization energy in the negative winding 21.
i and the energization time Δtonj of the negative winding 21 (falling b of the negative winding voltage Vi)
Rise of primary winding voltage ■1+1 from i a i 4-1
) are each over 1m5ec.

The microcomputer 50 is connected to the collector of the transistor 42 through its input port, and repeatedly executes a computer program stored therein in accordance with the flowchart shown in FIG. 4, and during this execution,
As will be described in the explanation of the operation below, various calculation processes necessary for masking the waveform shaping signal from the transistor 42, canceling this masking, setting the period, calculating the rotational speed N of the internal combustion engine, etc. are performed. Note that the waveform shaping circuit 40 and the microcomputer 50 constitute a signal processing device.

In this embodiment configured as described above, if the device of the present invention is operating under the operation of the internal combustion engine of the vehicle, the microcomputer 50 executes the computer program in step 61 according to the flowchart of FIG. After starting, the operation through steps 62 to 71 is about Q, 1m5e.
It is executed repeatedly at c. Therefore, the waveform shaping circuit 4
If o generates the waveform shaping signal S1 in response to the primary winding voltage Vi from the transistor 12 (see FIG. 3), the microcomputer 5o generates the waveform shaping signal S1 in response to the falling edge At of the waveform shaping signal S1 in step 68. rYEsJ, and in step 70 both count data C1 and C2 are set to zero.

Next, the microcomputer 50 uses the step 62 to add "1" (corresponding to 0.1 m3ec of one execution time of the computer program) to the count data C1-0 to update the count data c1, and in step 63 ,
Counting data CI<setting data DI in step 62
(L m which is the discharge time of the primary winding of the ignition coil 20
(previously stored in the microcomputer 5o as corresponding to s e c or higher) is determined to be rNOJ.

This means that the rise al of the -order winding voltage Vi (i.e.,
Immediately after the falling edge AI of the waveform shaping signal S1, various noises na (see FIG. 3) that tend to be mixed into the waveform shaping signal s1 due to ignition of the internal combustion engine, etc. are detected by the microcomputer 50.
4 means that it is reliably masked from

When C1≧D1 during the cyclic operation of both steps 62.6'3, the microcomputer 50 determines l-Y E S J in step 63 and advances the computer program to step 64.

This word means that the masking of the waveform-shaped signal S1 that occurs immediately after the falling edge A1 of the waveform-shaped signal s1 is cancelled. If the waveform shaping signal Sl (i.e., the input port of the microcombiator 5°) is at a low level at this stage, the microcomputer 50 performs step 64.
rNOJ is determined at step 62, and the computer program returns to step 62. Thereafter, when the determination in step 64 is rYEsJ based on the rising edge B1 of the waveform shaping signal s1, the microcomputer 5o, in step 65, converts the count data C1 in step 62 to <step 69
rNOJ is determined based on 1/2 of the cycle data T (corresponding to the preceding waveform shaping signal of the waveform shaping signal s1) that has been sent at step 62, and the computer program returns to step 62. This means that CI after rising BI of waveform shaping signal s1
This means that the waveform-shaped signal s1 and the noise □b (see FIG. 3) that tends to occur during this period are reliably masked until the waveform shaping signal s1 becomes equal to T/2.

Next, when the determination in step 65 becomes rYEsJ, the microcomputer 5o adds "1" to the count data C2=0 in step 66 to update the count data C2, and in step 67, δ1 in step 66 is updated.
Based on the numerical data C2<setting data D2 (previously stored in the micro combinator 50 as corresponding to the energization time of the ignition coil 20 of 1 m5 ec or more), rNOJ is determined, and the computer program returns to step 62. 1. While the waveform shaping signal s1 is rising, that is, while the ignition coil 20 is energized, the waveform shaping signal S1 and the noise nc that tends to occur during this period (see FIG. 3) can be reliably masked from the microcomputer 5o. means.

If C2≧D2 during such calculation, the microcomputer 5o determines YESJ in step 67 and advances the computer program to step 68. This means that all masks of the waveform shaped signal S1 from the microcomputer 5o have been released. However, during the repetition of the determination with rNOJ in step 68, when the determination in step 68 becomes rYESJ based on the falling edge A2 of the waveform shaping signal 32 (see FIG. 3) following the waveform shaping signal s1, the micro In step 69, the computer 50 performs step 62.
The latest count data C1 in is updated as periodic data T. In such a case, the noise generated during energization of the ignition coil 20 is reliably masked, and this mask is used as the waveform shaping signal S.
2, the period data T-C1 in step 69 accurately corresponds to the period of the primary winding voltage V1.

Thereafter, the microcomputer 50 resets Cl-C2=0 in step 70, and calculates the rotational speed N of the internal combustion engine in step 71 based on the reciprocal of the periodic take T=C1 in step 69.

In such a case, the periodic data T=C1 can be obtained with high accuracy as described above, so the rotational speed N will also be a highly accurate value.

In the above embodiment, an example was explained in which the periodic data T=CI obtained in step 69 was used to determine the rotational speed N. Periodic data T may be used as necessary data, and rYE in step 68
The timing for determining sJ may be used as the reference control timing in the electronic control system described above.

Further, in the embodiment, the period Ti+1 of the waveform shaping signal Si+1≧the period T i /2 of the waveform shaping signal St
Although an example has been described, the example is not limited to this, and Ti+l≧T i / depending on the type of internal combustion engine and the number of cylinders.
It may be implemented as 3-2 Ti/3.

[Brief explanation of drawings]

FIG. 1 is a diagram corresponding to the configuration of the claimed invention, FIG. 2 is a block diagram showing an embodiment of the device of the present invention, and FIG. 3 is a diagram of each output waveform of an ignition coil and a waveform shaping circuit. and FIG. 4 are flowcharts showing the operation of the microcomputer. Explanation of symbols 20... Ignition coil, 40... Waveform shaping circuit, 50
...Microcomputer. Figure 1

Claims (1)

[Claims] A waveform shaping means is provided for sequentially shaping the primary winding voltage generated from the ignition coil in the ignition cycle of the vehicle internal combustion engine and generating a waveform shaping signal, and each of these waveform shaping signals is necessary for control by the vehicle electronic control system. In the signal processing device, the generation time of the trailing waveform shaped signal is determined by comparing the leading waveform shaping signal and the trailing waveform shaping signal that are successively generated from the waveform shaping means. Comparing means for masking the following waveform-shaped signal when it is shorter than a predetermined time set within about 1/3 to 2/3 of the period of the waveform-shaped signal, and canceling the mask when it is longer; and unmasking by the comparing means. At the bottom, when there is a level change in the trailing waveform shaped signal, the elapsed time from the level change of the preceding waveform shaped signal under mask removal by the comparing means to the level change of the trailing waveform shaped signal is calculated. A setting means for setting a period of a waveform shaping signal, and a period set by the setting means is a period of a signal necessary for control by the electronic control system. Signal processing equipment for.