JPH0320763B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a digital control method for controlling fuel injection timing of an automobile.

If the response speed of a hydraulic actuator used in a digital control system with a feedback loop is slow, hunting may occur even with simple on/off control where the application time of the instruction signal is constant. Never. However, when increasing the response speed,
Hunting phenomenon is likely to occur.

This is almost always true within the control system.
This is because there are components of response delay and hysteresis. Furthermore, in digital control, in addition to the response delay and hysteresis mentioned above, the rise of the instruction signal sent to the hydraulic actuator, regardless of the magnitude of the control deviation value. , or the fact that the gain change at the end is forced to be abrupt makes hunting more likely to occur.

To solve these problems, conventionally, the signal to the hydraulic actuator is a periodic pulse signal that vibrates in both directions, and the duty ratio of the two directions is controlled, so that the average position of the hydraulic actuator is controlled vibrationally. However, the control is essentially similar to analog control, thereby preventing the hydraulic actuator from moving on and off excessively and causing hunting in its control. (pulse width modulation)
There are control methods such as

However, in these control methods based on duty ratio control, the solenoid valve used in the hydraulic actuator is constantly used in vibration mode, so the number of on/off times of the solenoid valve is equivalent to the number of vibrations.
Repeated turning off deteriorates the durability of the solenoid valve, and thus it is not appropriate to employ such duty ratio control for controlling devices that require durability.

The purpose of the present invention is to solve the above problems.
It is an object of the present invention to provide a control method for digital control that improves the responsiveness and control accuracy of a control system without impairing durability.

To explain the present invention based on an embodiment, FIG. 1 shows a system diagram when a digital control method according to an embodiment of the present invention is used to control a fuel injection timing adjustment device 2, and shows a system diagram of a diesel engine. Gear 1c fitted on crankshaft 1a of 1
and a gear 2c fitted to the input shaft 2a of the injection timing adjustment device 2 form a gear connection, and the output shaft 2b of the injection timing adjustment device 2 drives the fuel injection pump 4. 2 is
The rotational phase angle between the input shaft 2a and the output shaft 2b is changed according to the operating state of the diesel engine 1,
This allows the injection timing in the fuel injection pump 4 to be set appropriately, and the injection timing adjustment device 2 uses a known device.

The hydraulic pump device 3 is driven via gears 2c and 3a, and the hydraulic pump device 3 is connected to a pipe 3b.
It serves as a constant oil pressure source for the solenoid valve 5F via the solenoid valve 5F.

A disc 1b for measuring rotational angle and rotation speed is fitted onto the crankshaft 1a, and a similar disc 4a is fitted onto the output shaft 2b, and the circumferences of each of the discs 1b and 4a are fitted. On the top, protrusions are arranged at equally divided positions in the circumferential direction, and the disc 1b
Electromagnetic pickups 5H and 5G for detecting the rotational position of the protrusion are fixedly installed at positions on the circumferences of the protrusions and 4a, respectively. Note that 5a and 5b are electric wires.

The electric wire 5c is an input interface 5 for inputting the displacement of the accelerator pedal that operates the diesel engine 1.
The electric wire 5d is for transmitting the water temperature in the water jacket of the diesel engine 1 to the input interface 5A, and the electric wire 5e is for transmitting the atmospheric temperature to the input interface 5A. .

Input interface 5A, central processing circuit 5
B, memory 5E and output interface 5D
The electric wire 5k consists of one electric wire _5k1 in FIG. 3 and the other electric wire _5k2 not shown, and the output in the microcomputer 5 is electromagnetic via the electric wire 5m. It controls the valve 5F, and the solenoid valve 5
F is connected to the injection timing adjustment device 2 via the hydraulic pipe 5n.
It operates the hydraulic actuator inside.

As shown in FIG. 2, the input interface 5A is composed of a Schmitt circuit 5AB, an analog multiplexer 5AD and an A-D converter 5AE, and 5p, 5q, 5r, 5s and 5t are electric wires, respectively.

FIG. 3 shows one output interface 5D 1 in the circuit diagram of the output interface _{5D, and one electric wire 5k 1 ,} which is the output of the central processing circuit 5B, is connected to the resistor R ₁ . The electric wire 5u is connected to a constant voltage power supply, and the electric wire 5m ₁ is connected to the first
One solenoid 5F ₁ of the solenoid valve 5F in the figure
where D is the flywheel diode, R ₂ and R ₃ are resistors, TR ₁ and
TR ₂ is a transistor.

The other output interface to which the other electric wire _5k2 is input is omitted because it is the same as in FIG. 3.

In the configurations shown in FIGS. 1, 2, and 3 above, the basic operation will be explained. The diesel engine 1 is driven by the operation of an accelerator pedal (not shown), and the fuel injection pump 4 is connected to the crankshaft 1a and the gear. 1c and 2c, input shaft 2a,
The injection timing adjustment device 2 is driven via the injection timing adjustment device 2 and the output shaft 2b, and the injection timing adjustment device 2 controls the rotational speed of the diesel engine 1, the displacement of the accelerator pedal, and the water temperature of the water jacket (hereinafter simply referred to as water temperature).
The control is ultimately controlled by the hydraulic signal (control power) from the pipes 5n (plurality) to move the hydraulic actuator in the injection timing adjustment device 2 to one side or the other. As a result, the injection timing adjustment device 2 changes the relative rotational phase angle (hereinafter referred to as rotational phase angle) between the input shaft 2a (that is, also equivalent to the crankshaft 1a) and the output shaft 2b, and as a result, The injection timing of the fuel injection pump 4 is appropriately set.

The injection timing is set by the solenoid valve (control unit) 5 according to the output instruction signal from the microcomputer 5.
F is turned on or off to one side or the other, and the hydraulic signal from the solenoid valve 5F amplified by this operation sets the injection timing adjustment device 2.Hereinafter, the solenoid valve 5F will be operated and set. The operation of the controlling microcomputer 5 will be explained.

The displacement of the accelerator pedal, the water temperature, and the atmospheric temperature are detected in analog form by detectors (not shown), and as shown in FIG. 2, command signals are sent from the central processing circuit 5B via the electric wire 5r at any time. , the respective detection values are alternately selected in the analog multiplexer 5AD, and the alternately selected detection signals are A-
In the D converter 5AE, the analog values are converted into digital values and each is input to the central processing circuit 5B.

The respective rotation angles of the crankshaft 1a and the output shaft 2b are determined by the electromagnetic pickups 5H and 5.
G, and the respective detected signals are the signals 5as and 5bs shown in FIG.
The detection signal is input to the Schmitt circuit 5AB (FIG. 2).

Note that the horizontal axis in FIG. 6 indicates elapsed time.

Pulse signals sa and sb in FIG.
It shows the voltage change value that occurs when the voltage exceeds (passes).

Each of these pulse signals sa and sb is
In the Schmitt circuit 5AB (FIG. 2), the signals _pa1 and pb are converted into rectangular waveform pulse signals and input to the central processing circuit 5B.

As the rotational speed of the crankshaft 1a increases, the waveforms of the pulse signals sa and sb change as shown by sa', so the pulse signals _pa1 and pb whose waveforms are shaped with reference to the reference voltage level d are
pa changes as ₁ ′, but the pulse signals sa and sb
Since the positions of points a and b of zero voltage in are not affected by the rotational speed, the pulse signal pa ₁
and pb have their reference points at elapsed times corresponding to points a and b.

t ₁ and t ₂ each indicate the measurement time between the pulse signals pa ₁ and pb and the pulse signals pa ₁ and pa ₂ , respectively, and due to their properties, the input shaft 2a and the output shaft 2b The rotational phase angle pe between and the rotational speed n of the crankshaft 1a are as follows.

pe = (c ₁ × t ₁ ) / t ₂ ... (1) n = c ₂ / t ₂ ... (2) However, c ₁ and c ₂ are constants determined by the number of protrusions on the discs 1b and 4a. be.

In the memory 5E in FIG. 1, various data necessary for calculation in the central processing circuit 5B are stored.

To explain an example of this stored data, the fuel injection timing of the diesel engine 1 is ideally set based on the water temperature, the atmospheric temperature, the displacement θ of the accelerator pedal, and the rotational speed n of the crankshaft 1a. In this case, the fuel consumption rate or exhaust gas composition of the diesel engine 1 can be optimized, and for this purpose, the memory 5 is
Among these relationships, for example, the target rotational phase angle peo to be set by the injection timing adjustment device 2 in the relationship between the displacement θ of the accelerator pedal and the rotational speed n of the crankshaft 1a is expressed as shown in FIG. It is stored in the map state.

In addition, each + mark in FIG. 5 is p ₃₃ , p ₃₄ ,
As shown in p ₄₃ and p ₄₄ , each target rotational phase angle corresponding to the relationship between the displacement θ of each accelerator pedal and the rotational speed n of the crankshaft 1a is stored at equal intervals, and these are Values that change according to changes in temperature are stored.

In addition, in FIG. 5, the electromagnetic pick-up 5H
Actual operating point p determined by the rotational speed n found from and the displacement θ of the accelerator pedal at that time.
The target rotational phase angle peo is determined by the target rotational phase angles p ₃₃ , p ₃₄ , p ₄₃ and p ₄₄ in the neighborhood e of point p, and the neighborhood e is shown in an enlarged view in FIG.

In FIG. 4, Ld and dL are the displacement differences of the accelerator pedal, nd and dn each indicate the rotation difference, and the target rotational phase angle peo at point p is calculated in the central processing circuit 5B using the following formula. ing.

peo={(A-B)dn/nd}+B ……(3) However, A={(p ₄₄ −p ₃₄ )dL/Ld}+p ₃₄ ……(4) B={(p ₄₃ −p ₃₃ ) dL/Ld}+p ₃₃ (5) Note that all of the above equations (1) to (5) are stored in the memory 5E.

The target rotational phase angle peo obtained by the above equation (3) is compared with the actual rotational phase angle pe obtained from the equation (1), and based on the comparison, the central processing circuit 5B performs a calculation. will proceed.

That is, for each deviation Er between the target rotational phase angle peo and the actual rotational phase angle pe, a pulse-shaped rectangular wave with an application time ts is output to the electric wire 5k in FIG. The relationship with
The relationship is as shown in the figure, and the characteristics on the right side of the ts axis in Figure 7 indicate the application time of the signal applied to the electric wire _5k1 in Figure 3, and the characteristics on the left side of the ts axis, which are not shown above, are Other wire 5k ₂
shows the application time of the signal given to Furthermore, the slopes of the characteristics on both sides of the ts axis in FIG. 7 are different. This is because the load resistance force when operating the injection timing adjustment device 2 has different values when operating it in one direction and when operating it in the other direction.

The calculation steps in the central processing circuit 5B using FIG. 7 will be explained below.

Step 1) Find peo−pe=Er.

Step 2) Store the absolute value of the deviation Er in memory 5E.
Compare with the respective absolute values of the minimum standard deviation Ero and the maximum standard deviation Er ₁ stored in .

Step 3) When the absolute value of the deviation Er is smaller than the absolute value of the minimum standard deviation Ero, the voltage value of the instruction signal is set to zero.

Step 4) The absolute value of the deviation Er is the minimum standard deviation
Greater than the absolute value of Ero and the maximum standard deviation
When the absolute value of Er ₁ is smaller than the absolute value of Er 1, the central processing circuit 5B determines the sign of the deviation Er, and when the deviation Er is positive, it gives this as one of the instruction signals to the electric wire 5k ₁ in FIG. When Er is negative, this is given to the aforementioned electric wire _5k2 as the other instruction signal. At this time, the application time ts of the pulse signal in one instruction signal or the other instruction signal is determined by adding the minimum application time tso in FIG. 7 to the application time proportional to the deviation Er. have.

Step 5) When the absolute value of the deviation Er is larger than the absolute value of the maximum standard deviation Er ₁ , the electric wire 5k ₁ or 5k ₂ is continues to output instruction signals.

The instruction signal characteristics resulting from the above calculation are as shown in FIG.

In addition, in Fig. 8, the upper pulse (instruction signal
pk ₁ , pk ₂ ) are given to the electric wire 5k ₁ , the lower pulse is given to the electric wire 5k ₂ , and the vertical axis V shows the voltage,
The horizontal axis t indicates elapsed time.

What is important here is that in the above calculation step 4), the application time of the instruction signal output when the deviation Er occurs is the basic minimum application time ts ₀ plus the application time proportional to the deviation Er. It is in the point where it is.

This means that to correct the deviation,
The first pulse instruction signal indicates that the purpose is to converge the set value of the load within the target tolerance. In order to achieve such a purpose, we experimentally determined in advance, for each magnitude of deviation, the application time of the instruction signal that corresponds to the time when the deviations are brought within the tolerance by one instruction signal. The length is determined, and the relationship is determined experimentally with the application time.

Therefore, the correction control of the deviation by the calculation step 4) is designed to bring about a control within or near the allowable deviation by issuing only one instruction signal for the deviation. It is something.

However, if the deviation still deviates from the target allowable deviation as a result of the first instruction signal transmission, a second instruction signal is further transmitted by the method described below.

In the above calculation steps 1) to 5), the first instruction signal pk ₁ is applied to the electric wire 5k in FIG. 1, as shown in FIG. 9, and the application time ts of the instruction signal pk ₁ ends; Even at the time of completion, the operation of the solenoid valve 5F (FIG. 1) has not stopped.

This is due to the following reasons.

That is, as shown in FIG. 9, the first instruction signal pk ₁ is applied to the electric wire 5k at t=ts ₁ , and if, for example, the pk ₁ is the instruction signal on one side, then the pk ₁ is applied to the wire 5k ₁ in FIG. 3, and the voltage of this signal is applied to the base of the transistor TR ₁ through the resistor R ₁ , resulting in
The current I from the constant voltage source is 5 u and 5 m ₁
The current flows from the current to the ground via one solenoid _5F1 , and in this case, the current characteristics I with respect to the elapsed time t are as shown in f, g, h, i, and j shown in FIG.

This means that even if a rectangular voltage (instruction signal pk ₁ ) is applied to the electric wire 5k ₁ , the current I gradually increases between ts ₁ and f due to the inductance of the solenoid 5F ₁ . When point f is reached, the spool valve in the solenoid valve begins to move. As a result, due to this movement, an electromotive force is generated in the coil of the solenoid _5F1 , and the current I decreases between f and g, and the spool valve is completely opened at point g. When it becomes a state and stops its movement,
The decrease in the current I also ends.

Furthermore, as described above, even after the solenoid valve 5F is completely opened, if the voltage of the instruction signal continues to be applied to the electric wire _5k1 , the current increases again as shown in the characteristics between g and h. Eventually, its value will become saturated.

After the above action, when the voltage of the instruction signal on the electric wire _5k1 becomes zero at point h where the elapsed time t becomes t=ts, the flywheel diode D
and resistor R ₃ , the current I becomes h~i
It decreases while exhibiting the characteristics shown in between.
Since the spool valve starts to close when it reaches point i, the movement of the spool valve generates an electromotive force in the coil of solenoid _5F1 , until it reaches point j, when the spool valve finishes closing completely. , the current increases again and decreases again after point j.
It should be noted that when an instruction signal is applied to the aforementioned electric wire _5k2 (not shown), the other solenoid valve 5F in FIG. 1 is actuated by performing the same action on the other side.

In this way, even if the instruction signal pk ₁ disappears at t = ts, the solenoid valve 5F is activated at point t at point j in FIG.
This means that the valve is open until = ts ₂ , and this
Correction of the deviation Er continues even between ts and ts ₂ . Note that this phenomenon also occurs in other types of control parts other than solenoid valves, including the output interface 5D, and this is because the control part has mechanical or electrical inertia. be.

In the operation of the above embodiment, as described above, the electromagnetic pickups 5H and 5G are
Starting from detecting the pulses pa ₁ , pb and pa ₂ shown in the figure, the instruction signal pk ₁ is finally sent to the solenoid valve 5F.
As a result, the solenoid valve 5F is t=ts ₁
By operating the hydraulic actuator of the load during ~ts ₂ , a series of control strokes is completed, and in the next control stroke, it is determined whether the instruction signal pk ₂ shown in FIG. 8 should be transmitted. is again the calculation of the above-mentioned equations 1) to 5) and calculation step 1)
~5), between the start and end of the series of control steps, t=
Regardless of the time interval ts ₁ to ts ₂ , the pulse signals 5ap and 5bp in FIG.
Pulses pa ₁ , pb, pa ₂ are applied to wires 5b and 5a in the figure.
It is causing...

This is because the measurement times t ₁ and t ₂ in FIG. 6 become shorter in inverse proportion to the rotational speed of the crankshaft 1a, and on the other hand, the application time ts of the instruction signal pk ₁ and the solenoid valve including the output interface 5D become shorter. This is because the response delay time ts to _ts2 of 5F has nothing to do with the rotational speed of the crankshaft 1a.

However, the deviation Er is detected and, as a result, the instruction signal pk ₁ is transmitted, thereby ending _the above-mentioned series of control steps. It is desirable that the subsequent deviation detection be performed immediately after the above-mentioned t=ts ₂ (FIG. 9).

As mentioned above, the application time ts of the instruction signal is set at a time interval corresponding to the detected deviation Er, and therefore, when the instruction signal has been transmitted and the solenoid valve 5F has finished operating. At this time, the actual deviation Er at that time is often within the desired range or in the vicinity of the desired range, as described above.

_On the other hand, if the next deviation Er is detected between ts ₁ and ts ₂ in FIG _. The application time of pk 2 is superimposed on the instruction signal pk ₂ and has a very long time interval, so that the control often overshoots.

For these reasons, the control in the present invention is
In the above-described operation, the following method is used to detect the subsequent deviation Er.

That is, as explained in Fig. 6 and equations 1) to 5), the series of data detection up to calculating the deviation Er is performed when the electromagnetic pickup 5H detects the first data of pulse pa ₁ (Fig. 6). Then, the electromagnetic pick-up 5G detects the second data of the pulse pb, and then the electromagnetic pick-up 5H detects the final data of the subsequent pulse pa ₂ , and also pulses pa ₁ and pa ₂ . Within the detected required time _t2 , by detecting the displacement θ of the accelerator pedal, data for calculating the current deviation is completed, and based on these data, calculations of equations 1) to 5) are performed, In addition, calculation steps 1) to 5) are performed, and the time required for a series of data detection from the detection of pulse pa ₁ to the detection of pulse pa ₂ is as clear from the configuration in FIG. 1 described above. , is inversely proportional to the rotational speed n of the diesel engine 1.

From this, the time ts ₁ to _{ts 2} from when the instruction signal pk ₁ is transmitted until the solenoid valve 5F finishes operating
The number of times that a series of data can be detected in the deviation detection described above increases as the rotation speed of the diesel engine 1 increases.

On the other hand, the application time ts of the instruction signal pk ₁ is
It is determined by the initial deviation Er when used to transmit the pk ₁ , and the response delay of the output interface 5D and the solenoid valve 5F is determined at the time of design, so in the end, the hydraulic actuator It can be seen that the number of times that a series of data can be detected for the next deviation detection within the required time ts ₁ to ts ₂ during which the motor is in operation is a function of the initial deviation value Er and the rotational speed n.

Therefore, in the embodiment of the present invention, the initial deviation Er required to transmit the instruction signal pk ₁ is
Using the data of the rotational speed n at that time, the central processing circuit 5B calculates the timing of adopting a series of detection data necessary to calculate the next deviation of the first deviation Er, and the timing is as follows. As shown in FIG. 9, the final data detection (detection of pulse pa ₂ ) in the series of detections to be adopted is at least t=ts ₂
The relationship is selected so that it will take place after the lapse of time.

That is, if the rotational speed n is very low, t=
From time ts ₁ , the first pulse pa ₁ that appears next may appear after t=ts ₂ , but above a normal rotational speed, the series of detected pulses pa ₁ and pb ₂ Occurs within the time period ts ₁ to ts ₂ ,
When detecting pulse pa ₂ of the final detection data, t=ts ₂
It is possible to do this immediately after.

The reason why such a detection method is adopted is that in order to solve the problem of only preventing the control system from overshooting, the first adopted data pa ₁ of the series of detections is t=ts ₂ or later may be used, but in that case, when the final data pa ₂ appears, it will be data at a delayed time since t = ts ₂ o'clock, and the deviation Er will be calculated based on these data. and the next instruction signal
If pk ₂ is to be transmitted, there is a risk that the response of the system will become slow. Therefore, it is desirable to use a combination of data occurring between t=ts ₂ as the series of detection data, and it is more desirable to use the last data (pulse pa _{2 )} of the series of combination data. ) occurs immediately after t=ts ₂ , the series of data adopted is the instruction signal
This is because it shows the latest data of the control results based on pk ₁ , and calculating and controlling the load (hydraulic actuator) based on the latest data is the most appropriate control that does not cause the hunting phenomenon.

To summarize the above invention, periodic pulse signals indicating the respective rotational angular positions of the crankshaft 1a and the output shaft 2b detected by the electromagnetic pickups 5H and 5G are always sent periodically and continuously to the central processing circuit 5B. However, the central processing circuit 5B
A set of data of pulses pa ₁ , pb and pa ₂ which is a series of data in FIG. 6 necessary for calculating equations 1) to 5) and calculating steps 1) to 5) is As shown in FIG. 9, the final data pa ₂ should be used to transmit the next instruction signal pk ₂ by adopting the data combinations that occur after t=ts ₂ and using the data in the series of sets. It determines whether or not the instruction signal pk2 is applied, and also determines the application time ts of the instruction signal _pk2 .

In addition, the pulse shown in the virtual line diagram in FIG.
pao and pbo indicate data that is input to the central processing circuit 5B but is not included in the series of data, and other pa ₁ , pa ₂ and
pb is what is shown in FIG. 6 in relation to the instruction signal pk ₁ .

Furthermore, the final data of the above series of set data is
There are other methods for selecting combinations that have occurred at least after t=ts ₂ , such as those described below.

That is, at a time near t=ts ₂ , as shown in FIG. 9, approximately the solenoid coil 5F ₁ (or solenoid coil 5F ₂ not shown)
The determination can also be made by detecting that the current I flowing through has decreased to a certain value.
From that, t=ts ₁ for calculating the deviation Er
If the data of each set of all series of sets that will occur thereafter is temporarily stored in the memory 5E, and when the central processing circuit 5B determines that t=ts ₂ has been reached, the central processing circuit 5B stores the data in the memory 5E. It is also possible to extract the last recorded set of data stored above from 5E and proceed with the calculation based on that data.

As is clear from the above description, the effects of the present invention are as follows.

Unlike the conventional method of continuing to output the instruction signal until the deviation becomes zero, after the detection of the deviation Er is completed, based on the detected deviation value Er, A method is adopted in which an instruction signal with an application time ts that corrects the value of the deviation Er to exactly zero is output. Therefore, the deviation Er is corrected to a value of almost zero by only one pulse of the instruction signal in that control cycle.

Therefore, the response of the control becomes very quick, and the number of signal transmissions applied to the solenoid valve is reduced, so that the durability of the solenoid valve is improved.

In addition, in the control of the present invention, if the deviation is still not corrected within the allowable deviation even after the first instruction signal, a second instruction signal is transmitted; For the next deviation detection, which is the criterion for determining whether or not to do so, the final data in the series of set data necessary to calculate the deviation shall adopt at least the value that occurs after t = ts ₂ in Figure 9. I have decided to do so.

Therefore, even if the first control result deviates from the allowable deviation as described above, the deviation should be small. The second control is
Compared to the method of using a deviation calculated from a series of set data detected before the first control result is obtained, control with less overshoot is possible.

[Brief explanation of the drawing]

FIG. 1 shows a system diagram when the digital control method of the present invention is used in a fuel injection timing adjustment device 2 of a diesel engine 1, and FIG. 2 shows an input interface 5 in FIG.
3 is a circuit diagram showing one of the output interfaces 5D1 in FIG. 1, and FIG. ₄ is a circuit diagram of the output interface 5D1 in FIG. FIG. 5, which is an enlarged view of neighborhood e, shows a map digitally showing the target rotational phase angle of the fuel injection pump determined by the relationship between the accelerator pedal θ and the engine rotational speed n. FIG. 6 shows, from the top, signals 5as and 5bs detected by electromagnetic pickups 5G and 5H in FIG.
In the Schmitt circuit 5AB shown in the figure, the characteristics of the signals converted into rectangular waveform signals 5ap and 5bp are shown. 7 shows the application time characteristics of the instruction signal applied to the electric wire 5k in FIG. 1, and FIG. 8 shows the instruction signal voltage V appearing on the electric wire 5k in FIG. 1 according to the characteristics in FIG. FIG. 9 shows the characteristics of the current I generated in the solenoid coil 5F ₁ by the instruction signal pk ₁ (shown by a dotted line), and the pulses pa ₁ , of FIG. 6 occurring in relation to the characteristics. Pa ₂ and pb are shown. The symbols used in the examples are as follows.
1: Diesel engine, 1a: Crankshaft, 1
b: disk, 1c: gear. 2: Injection timing adjustment device,
2a: input shaft, 2b: output shaft, 2c: gear. 3:
Hydraulic pump device, 3a: gear, 3b: piping. 4:
Fuel injection pump, 4a: disc. 5: Microcomputer, 5A: Input interface, 5
AB: Schmitt circuit, 5AD: Analog multiplexer, 5AE: A-D converter, 5B:
Central processing circuit, 5D: Output interface, 5
D ₁ : One output interface, 5E: Memory, 5F: Solenoid valve, 5F ₁ : One solenoid,
5G and 5H: Electromagnetic pick-up. 5a, 5
b, 5c, 5d, 5e, 5f, 5g, 5h, 5
j, 5k, 5k ₁ , 5m, 5m ₁ , 5p, 5q, 5
r, 5s, 5t and 5u: electric wire, 5n: piping,
5as, 5bs, 5ap and 5bp: signal. sa, sa′,
sb, pa ₁ , pa ₁ ′, pa ₂ and pb: pulse signal, pk ₁
and pk ₂ : instruction signal, t ₁ and t ₂ : measurement time,
θ: Displacement of the accelerator pedal, n: Rotational speed of the diesel engine 1, p ₃₃ , p ₃₄ , p ₄₃ and p ₄₄ : Target rotational phase angle in the injection timing adjustment device 2, Ld
and dL: displacement difference, dn and nd: rotation difference, p:
Actual operating point, d: reference voltage, a, b, c, f, g,
h, i and j: points, R ₁ , R ₂ and R ₃ : resistors,
TR ₁ and TR ₂ : transistor, D: diode, ts: application time of the square wave voltage (instruction signal) applied to the electric wire 5k, Er: difference between the target rotational phase angle and the actual rotational phase angle for the injection timing adjustment device 2. Deviation, Ero: Minimum standard deviation, Er ₁ : Maximum standard deviation.

Claims (1)

[Scope of Claims] 1. An actuator that operates a load is actuated by application of an instruction signal, and the application of the instruction signal includes: a; a detected value of a setting value set in the load; Calculate the deviation value from the target setting value to be set for that load, b; Compare the absolute value of the deviation value with the absolute value of the minimum standard deviation value, c; When the absolute value of the deviation value is smaller than the absolute value of the minimum standard deviation value, the value of the instruction signal is set to zero; d; When the absolute value of the deviation value is larger than the absolute value of the minimum standard deviation value, the value of the deviation value is set to zero; By determining the positive and negative signs, the instruction signal is sorted into one instruction signal or the other instruction signal; e; the application time of the classified instruction signal is:
The application time is obtained by adding the minimum application time to the application time proportional to the absolute value of the deviation value; The digital control system is characterized in that the final data of the series of data uses at least the data detected after the control of the final stage of the control system is completed due to the instruction signal. Control method.