JPS6053776B2 - Fuel injection timing control device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a fuel injection timing control device for an internal combustion engine.

The fuel injection timing of diesel engines and gasoline engines needs to be changed depending on the engine rotation speed and load amount.

In order to precisely control the injection timing, a feedback method as shown in FIG. 3, for example, is used.

In FIG. 3, a deviation detection circuit 101 detects a deviation between a target value signal 52 of the injection timing and an actual value signal Ba, and generates a deviation signal s. Output. The control circuit 102 is, for example, an integrating circuit, and outputs a deviation signal s. A control signal with integral characteristics is output. With this control signal, the injection timing control mechanism 103
to control the injection timing. The sensor 104 also detects the actual injection timing and outputs an actual value signal S3. In the feedback type control device as described above,
By giving the control signal an integral characteristic, steady-state deviation (offset) can be eliminated while maintaining control stability, and good control can be performed.

However, with integral characteristics, even when the deviation between the target value and the actual value is very large, the control signal changes according to a certain time constant, so there is a time delay before the actual value matches the target value. Therefore, during transient conditions such as sudden acceleration or sudden deceleration, the difference between the actual injection timing and the target value becomes large and H
There are problems such as an increase in the amount of emissions of C, NOO, etc., and an increase in noise.

The present invention has been made in view of the above problems, and an object of the present invention is to provide a fuel injection timing control device that improves responsiveness during transient conditions while maintaining the advantage of integral characteristics.

In order to achieve the above object, the present invention is configured to change the integral time constant according to the magnitude of the deviation between the target value and the actual value, or the operating variables related to the deviation and the rate of change. Improves responsiveness.

The present invention will be explained in detail below based on the drawings.

FIG. 10 is a block diagram showing the overall configuration of the present invention. In FIG. 10, the actual value detection means 201 is for detecting the actual fuel injection timing, and for example, the second
A potentiometer 68 or the like can be used to detect the sleeve position as shown in the figure.

Further, the deviation detection means 202 detects the actual value and the target value Ss.
．． Detect the deviation Sh from

Next, the integrating means 203 integrates and outputs the above deviation Sh.

Further, the control means 204 controls the integration time constant of the integration means 203 to be adjusted to the magnitude of the deviation Sh or to an operating variable S related to the deviation.
It is changed in accordance with the rate of change of d.

As the above-mentioned operating variable Sd, for example, the engine load amount (sleeve position, accelerator pedal position, etc.) can be used as described later.

Further, the deviation detecting means 202, the integrating means 203, and the controlling means 204 described above can be configured using, for example, a microcomputer.

Next, the fuel injection timing control mechanism 205 controls the integration means 2 described above.
For example, the injection timing control mechanism shown in FIG. 2, the electromagnetic valve 54 and its drive circuit (for example, 110, 111, Q1, etc. in FIG. 4)
It can be constructed from etc.

FIG. 1 is a diagram showing an example of a diesel engine control device to which the present invention is applied.

In Fig. 1, 1 is an air cleaner, 2 is an intake pipe, and 3 is an air cleaner.
is the main combustion chamber, 4 is the swirl chamber, 5 is the glow plug, 6 is the injection nozzle, 7 is the injection pump (details will be described later), 8 is the exhaust pipe, 9 is the throttle valve that adjusts the amount of intake air, and 10 is the throttle valve opening degree. A diaphragm valve to control, 11, an EGR valve to control the amount of EGR recirculated from the exhaust pipe 8 to the intake pipe 2 (exhaust gas recirculation amount), 12
and 13 are solenoid valves.

Further, 14 is a vacuum pump serving as a negative pressure source, and can be used in common with a brake servo pump, for example. Further, 15 is a constant pressure valve that creates a constant negative pressure from the negative pressure given from the vacuum pump 14, 16 is a battery, 17 is a glow relay that controls the energization of the glow plug 5, and 18 is a control unit that controls the fuel injection amount of the injection pump 7. servo circuit, 19
is a glow lamp that indicates the energization state of the glow plug 5. Further, 20 is an accelerator position sensor that outputs an accelerator position signal 1S1 corresponding to the accelerator pedal position (depression angle), and 21 is a reference angle of the crank angle (for example, 120 sa).
a crank angle sensor that outputs a reference pulse IS2 for every unit angle (for example, 1) and a unit pulse IS3 for every unit angle (for example, 1);
2 is a neutral switch that detects that the transmission is in the neutral position and outputs a neutral signal 1S4; 23 is a neutral switch that outputs a vehicle speed signal 1S5 corresponding to the vehicle speed (detected from the rotation speed of the output shaft of the transmission) Vehicle speed sensor 24 is a temperature signal 1S6 corresponding to the engine cooling water temperature
The temperature sensor 25 is a lift sensor that outputs an injection start signal 1S7 every time the injection nozzle 6 starts fuel injection, and is, for example, a switch or a piezoelectric element operated by fuel pressure. Further, 26 is an atmospheric density sensor that outputs an atmospheric density signal 1S8 corresponding to the temperature and pressure of the atmosphere. In addition, sleeve position signals 1S, (
(Details will be described later), battery voltage signal 1S10, and other signals are used. Further, 27 is an arithmetic unit, such as a central processing unit (CPU) 28 and a read-only memory (ROM) 29.
, a readable/writable memory (RAM) 30, an input interface 31, and the like.

The arithmetic unit 27 receives each signal 1S1 to ISl given from the various sensors mentioned above.

It inputs signals such as a starter signal 1S11 given from a starter switch (not shown) (turned on when the starter motor is activated) and a glow signal 1S12 given from a glow switch, and outputs various control signals 0S1 to 0S7 for optimally controlling the diesel engine. do. The throttle valve opening control signal 0S1 and the EGR control signal αTO are pulse signals, and by controlling the duty of the solenoid valves 12 and 13 by changing the duty of these pulse signals, the throttle valve 9
and the opening degree of the EGR valve 11.

Further, the fuel cutoff control signal 0S3 controls opening and closing of a fuel cutoff valve 71 (for stopping the engine) in the injection pump 7.

Further, the fuel injection amount control signal 0S and the sleeve position signal 1S9 are given to the servo circuit 18, and the servo circuit 18 outputs the servo signal S1 so as to match both signals. By controlling the position, the fuel injection amount is controlled.

Further, the fuel injection timing is controlled by controlling the injection timing control mechanism in the injection pump 7 using the injection timing control signal α and the like.

The injection timing is determined by the injection start signal 1 from the lift sensor 25.
Feedback control is performed using S7. Further, by controlling the glow relay 17 using the glow control signal 0S6, the energization of the glow plug 5 is controlled.

Further, the energization state of the glow plug 5 is displayed by controlling blinking of the glow lamp 19 using the glow lamp control signal 0S7.

For example, the glow lamp 19 is turned on when energized, and turned off when not energized. Next, Fig. 2 shows the injection pump 7.
It is a sectional view of an example.

In FIG. 2, fuel is first sucked from an inlet 32 of the pump body by a feed pump 34 driven by a drive shaft 33 connected to the engine output shaft.

The fuel discharged from the feed pump 34 is transferred to a pressure regulating valve 35.
The supply pressure is controlled by the pump housing and supplied to the pump chamber 36 inside the pump housing.

The fuel in the pump chamber 36 lubricates the working parts and is simultaneously sent to the high pressure plunger pump 38 through the suction boat 37. The plunger 39 of this pump 38 is connected to an eccentric disk 4 connected to the drive shaft 33.
0, and is driven by the drive shaft 33 via a joint 41 in synchronization with the engine circuit.

Further, the eccentric disk 40 has the same number of face cams 42 as the number of engine cylinders, and reciprocates by a predetermined cam lift each time the face cams 42 ride over a roller 44 disposed on a roller ring 43 while rotating.

Therefore, the plunger 39 reciprocates while rotating,
Due to this reciprocating movement, the fuel sucked from the suction boat 37 is forced from the distribution boat 45 to the injection nozzle 6 shown in FIG. 1 through the delivery valve 46.

At this time, the fuel injection timing can be freely adjusted by changing the relative position between the face cam 42 and the roller 44 using the roller ring 43.

The roller ring 43 is connected to a plunger 48 via a driving pin 47.

In FIG. 2, for convenience of explanation, the axis of the planon gear 48 is rotated by 90 degrees, and the feed pump 3 is rotated by 90 degrees.
The axis of No. 4 is also shown rotated by 90 degrees.

The cylinder 49 containing the plunger 48 is connected to the casing 5
It is slidably housed inside the cylinder 49.
An oil chamber 51 and an oil chamber 52 are defined at the right end and the left end, respectively.

Note that an orifice 49a and a passage 50a are provided for communicating the sharpening oil chamber 51, which the cylinder 49 has moved to the right, and the end face high pressure chamber 55. ) The oil chamber 51 communicates with the other oil chamber 52 and the suction side of the feed pump 34 through a fuel passage 53, and an orifice 50b and a solenoid valve 54 are provided at the connection between the oil chamber 51 and the fuel passage 53. is provided.

Further, the fuel pressure in the pump chamber 36 is introduced to the end face high pressure chamber 55 of the plunger 48 sliding in the cylinder 49 via the orifice 48a and the passage 56, and the low pressure chamber 57 on the opposite side is connected to the suction of the feed pump 34. The plunger 48 is pushed back by the elastic force of the spring 58, although the plunger 48 is in communication with the side and becomes close to negative pressure.

Since the fuel pressure in the pump chamber 36 increases in proportion to the rotational speed of the feed pump 34, the fuel pressure in the orifice 4 increases as shown in the figure.
When 9a is closed, the plunger 48 is pushed to the left in the drawing as the engine speed increases, thereby rotating the roller ring 43 in the opposite direction to the rotational direction of the eccentric disk 40. The injection timing becomes earlier in accordance with the rotation speed.

Furthermore, the cylinder 49 moves fully to the right in the drawing due to the rotational force of the eccentric disk 40 (at this time, the solenoid valve 5
4 is opened), the oil chamber 51 and the end high pressure chamber 55 communicate with each other via the orifice 49a and the passage 50a.
pressure can be controlled.

Therefore, the solenoid valve 54 is controlled by the injection timing control signal α, etc.
By controlling the opening and closing of the fuel injection valve, the injection timing can be electrically controlled. Next, how the plunger 48 responds when the solenoid valve 54 is turned on or off will be explained in detail. First, the response to the advance angle side will be explained.

When the solenoid valve 54 is open, oil flows to the orifice chair 4.
The fuel enters the end face high pressure chamber 55 and the oil pressure 51 via the 8a1 orifice 49a and the passage 50a, and flows to the low pressure side via the orifice 50b and the fuel passage 53.

When the solenoid valve 54 is closed in this state, the S oil of the hydraulic pressure 51 cannot escape to the low pressure side via the orifice 50b.

At this time, the end face high pressure chamber 55 and the oil pressure 51 are connected to the orifice 49.
a and the passage 50a, the oil pressure in both chambers is equal.Therefore, the oil pressure applied to the cylinder 49 is balanced, and the cylinder 49 is moved toward the left in the figure by the force of the spring 51a. (advanced angle side). Further, until the plunger 48 is in a balanced state against the force of the spring 58, oil flows into the end face high pressure chamber 55 through the orifice 48a, and the plunger 48 moves to the left in the drawing to advance. Next, the response to the retard side will be explained.

When the solenoid valve 54 opens, the oil in the oil chamber 51 flows into the orifice 50b.
The cylinder 49 moves to the right in the drawing because it escapes to the low pressure side through the cylinder 49.

Therefore, the end high pressure chamber 55 and the oil chamber 51 communicate with each other through the orifice 49a and the passage 50a, and the oil in the end high pressure chamber 55 escapes to the low pressure side, causing the plunger 48 to move to the right in the drawing and retard the angle. As described above, the response of the plunger 48 when the electromagnetic valve 54 opens and closes is rate-limited by the orifice 48a when the angle is advanced, and is rate-limited by the orifices 49a and 50b when the angle is retarded.

That is, one response speed is determined by the inflow and outflow speeds of oil. On the other hand, the amount of fuel to be injected is determined by the position of the sleeve 60 that covers the spill port 59 formed in the plunger 39.

For example, when the opening of the spill port 59 passes the right end of the sleeve 60 due to the rightward movement of the plunger 39, the fuel that had been pumped from the plunger pump chamber 61 to the distribution boat 45 passes through the spill port 59. The pump is then released into the pump chamber 36, thus ending the pumping. That is,
If the sleeve 60 is displaced to the right relative to the plunger 39, the fuel injection end time will be delayed and the fuel injection amount will be increased. Conversely, if the sleeve 60 is displaced to the left, the fuel injection end time will be brought forward and the fuel injection amount will be increased. This results in a decrease in the amount of injection.

The position control of the sleeve 60 described above is performed by a surf motor 62.

That is, the shaft 63 of the servo motor 62 is threaded, and a slider 64 having a threaded hole in the center is screwed into the shaft 63 of the servo motor 62. A link lever 65 is coupled to this slider 64 so as to be rotatable about a pin 66 as a fulcrum. The link lever 65 is rotatably attached around a fulcrum 67, and is attached to a pivot pin 7 at the tip of the link lever 65.
The sleeve 60 is locked through 2. Therefore, when the servo motor 62 rotates in the forward and reverse directions, the slider 64 moves left and right, which causes the link lever 65 to rotate about the fulcrum 67 and move the sleeve 60 left and right.

The servo motor 62 is controlled by a fuel injection amount control signal V (Y5
This is performed using the servo signal S1 outputted by the servo circuit 18 in response to the signal S4.

Therefore, there is no direct correspondence between the accelerator pedal and the fuel injection amount.

In other words, the accelerator pedal only serves as a means to convey the driver's intention, such as "not to accelerate" or "to decelerate," to the computing device 27, and the computing device 27 determines the optimal fuel injection amount according to the driving state at that time. The optimal control is performed using the fuel injection amount control signal C4. Further, the shaft of a potentiometer 68 provided near the servo motor 62 is coupled to the shaft 63 of the servo motor 62 by gears 69 and 70, so that the signal from the potentiometer 68 indicates the position of the sleeve 60. .

This signal becomes the sleeve position signal 1S9. On the other hand, the electromagnetic type fuel cutoff valve 71 is controlled to open and close by the above-mentioned fuel cutoff control Shinning C3, and when cut off, the intake boat 37
The engine is stopped by closing the valve and cutting off the fuel.

The present invention relates to the control of injection timing, and when applied to a diesel engine, it relates to the control of the electromagnetic valve 54 shown in FIG. 2.

Note that the present invention is applicable not only to diesel engines but also to gasoline engines. This will be explained in detail below.

FIG. 4 is a block diagram of one embodiment of the present invention.

In FIG. 4, the counter 105 is set at the time when the reference pulse IS2 from the crank angle sensor 21 is given, and counts the unit pulse IS3 inputted after that time, and the injection start signal 1S7 from the lift sensor 25 is set. Reset when given.

Therefore, the output of the counter 105 is a value corresponding to the crank angle from the reference position to the position where fuel injection is actually performed, that is, a value corresponding to the actual value of the injection timing.
This value is converted into an analog signal by the DA converter 106, and an actual value signal 1T. ．． The signal is sent to the differential amplifier 108 as a signal. On the other hand, the target value calculation circuit 107 is, for example, a function generation circuit, and calculates the engine rotational speed calculated from the unit pulse IS, and the potentiometer 68 (second
The optimum target value of the injection timing is calculated from the actual position (value corresponding to the injection amount) of the sleeve (60 in Fig. 2) given by the sleeve position signal 1S9 from the sleeve position signal 1S9 (corresponding to the same symbol in the figure), and corresponding outputs the target value signal ITs. In addition,
The relationship between the rotation speed, sleeve position, and target value is as shown in FIG. 5, for example.

The curve in FIG. 5 is an equal target value curve, and the value increases in the direction of the arrow. Next, the differential amplifier 108 outputs the target value signal 1Ts and the actual value signal 1Tw. Deviation ΔIT (ΔIT=
ITs-1Tf! 1) Output.

Next, the variable time constant integrator 109 outputs an integral signal S6 that integrates the deviation ΔIT, and at this time automatically changes the magnitude of the integration time constant according to the magnitude of the deviation ΔIT.

Note that details of the variable time constant integrator 109 will be described later. Next, the comparator 111 compares the dither signal (triangular wave) provided from the dither oscillator 110 with the above integral signal, thereby outputting a pulse signal having a duty ratio proportional to the value of the integral signal S.

By outputting this pulse signal as the injection timing control signal 0S5 and controlling the opening/closing of the drive circuit composed of the transistor Q1, etc., the solenoid valve 54 (corresponding to the same reference numeral in FIG. 2) that controls the injection timing is controlled by duty. Therefore, feedback control can be performed so that the actual injection timing matches the target value. Next, variable time constant integrator 109 will be explained in detail.

L FIG. 7 is a diagram of a first embodiment of the variable time constant integrator 109.

In FIG. 7, the absolute value circuit 112 inputs the input deviation Δ
Absolute value of IT! Output ΔITl.

Comparators 113 and 114 then apply their respective reference voltages Vl
, ■ Compare 2 (VKV2) and 1ΔITl, and find 1ΔIT
When l is larger, signals S8, S, which become high level are output. Furthermore, the switching circuits 115 and 116 are turned on when the signal S8 or S, respectively, becomes high level.

On the other hand, the operational amplifier 117, the capacitor C1 and the resistor t/L
Rl to R3 constitute an integration circuit, and its integration time constant is proportional to RCl (R is the combined resistance of R1 to R3).

Therefore, it changes as follows depending on the change in the integral time constant CtR. First, if lΔITI<V1<V2,
Since switching circuits 115 and 116 are both off, R=R1 and the integration time constant is RlCl.

Next, in the case of ■1≦lΔITl<V2, only the switching circuit 115 is turned on, so that R=]lamp L. R1+R2 Furthermore, ■If 2≦1ΔITl, both switching circuits are turned on, so R=RlR2R3? becomes.

RlR2+R2R3+RlR3 That is, the larger lΔITl becomes, the smaller the integral time constant becomes.

In the above embodiment, the integration time constant is changed in three stages, but it is also easy to subdivide the integral time constant into three stages.

Further, in the circuit shown in FIG. 7, the case where the integration time constant is set to zero when V1≦:ΔITl to rapidly reduce the deviation will be explained using FIG.

If R2=0 in FIG. 7 (in this case, 11
4,116 and R3 are unnecessary), as shown by the solid line in Fig. 6, at time T1 when V1≦1ΔITl, R=R2=0.
Since the integral time constant becomes O, the integral signal S6 immediately reaches the maximum (when ΔIT<0) or the minimum (when ΔIT>0), and this state is reached at the time T when ΔIT next passes the O point.
Continue until 2. Therefore, the duty ratio of the injection timing control signal O■ output from the comparator 111 is 100% or 0% from time T1 to T2, and the solenoid valve 54 remains open or closed, so ΔIT is rapidly 0
After exceeding 0 and overshooting a little, normal integral correction begins. The rate of change of Δ■T in this case depends on the inflow and outflow speeds of oil through the orifice of the injection timing control mechanism shown in FIG. 2, as described above. The rate is determined by Note that in the case of a conventional device that does not perform variable time constant control as described above, the change occurs as shown by the broken line in FIG.

As can be seen from Figure 6, the responsiveness of the present invention is significantly improved compared to the conventional device, so it is possible to perform good control even when the optimal injection timing changes suddenly, such as during sudden acceleration. I can do it. Next, FIG. 8 is a diagram of a second embodiment of a variable time constant integrator, and the same reference numerals as in FIG. 7 indicate the same parts.

The circuit shown in FIG. 8 is configured to change the integral time constant in accordance with the rate of change of operating variables related to the deviation Δ1T, such as the sleeve position and the accelerator pedal position.
The target value of the injection timing is, for example, as shown in FIG.
Varies depending on sleeve position.

Therefore, if the sleeve position changes rapidly, the target value also changes rapidly, and as a result, the deviation ΔIT increases. Therefore, the rate of change in sleeve position can be used instead of ΔIT. Generally, the rate of change in engine load may be used. In FIG. 8, the sleeve position signal 1S,
It is configured to detect the rate of change of the value and to provide the detected value to the absolute value circuit 112.

The other parts are similar to the circuit shown in FIG. Further, the accelerator pedal position (accelerator position signal 1S1 in FIG. 1) may be used instead of the sleeve position.

Next, the portion surrounded by the broken line in the circuit of FIG. 4 can be constructed using a microcomputer (27 in FIG. 1).

However, the calculation method in that case is naturally a digital method. FIG. 9 is an embodiment of a flowchart showing calculations when the above portion is configured by a microcomputer.

In FIG. 9, first, at P1, the actual value of the injection timing is 1T. ．． is read and the value is stored at a certain address in RAM. Next, in P2, a target value 1Ts of the injection timing corresponding to the rotational speed and the sleeve position is calculated by table lookup.

Next, in P3, the deviation ΔIT=IT8−■L is calculated.

Next, in P4, it is semi-determined whether lΔ■T1≧K, (K1 corresponds to the above-mentioned V1), and if YES, control is performed to make the integral time constant zero, and if NO, normal integral control is performed. . First, if NO at P, go to P5 and IΔITI≦K2(
However, it is determined whether K2 is less than or equal to a predetermined allowable width value.

If YES in P5, that is, if the deviation is within the allowable range, the correction amount is set to 0 in P6, and then the process goes to P8.

If NO in P5, that is, if the deviation exceeds the allowable range, the process goes to P, where the correction amount is set to a value obtained by reversing the sign of the deviation ΔIT, and then the process goes to P8. At P8, the above duty plus the correction amount is output as the current duty.

On the other hand, if YES in P4, the process goes to P, and it is determined whether ΔIT<0.

If YES at P, the duty is set to 100% using PIO, and when NO, the duty is set to 0% using Pll.

As explained above, according to the present invention, when there is a large deviation between the target value and the actual value of the injection timing, the integral time constant is reduced or set to 0 to rapidly change the control signal, so the response of the injection timing control is You can improve your sexuality.
Therefore, the injection timing can be controlled to the optimum value even during sudden acceleration/deceleration, so that it is possible to improve exhaust purification performance and driving performance, and also to reduce noise.

[Brief explanation of drawings]

Fig. 1 is a diagram of an example of a control device for a diesel engine to which the present invention is applied, Fig. 2 is a sectional view of an example of an injection pump, and Fig. 3 is a sectional view of an example of an injection pump.
Figure 4 is a block diagram of an example of an injection timing control system, Figure 4 is a block diagram of an embodiment of the present invention, Figure 5 is a characteristic example diagram of the injection timing target value, and Figure 6 is an example control characteristic diagram of the present invention. , FIG. 7 and FIG. 8 are respectively an embodiment of the variable time constant integrator of the present invention, FIG. 9 is an embodiment of a flowchart showing the calculation of the present invention, and FIG. 10 is an overall configuration of the present invention. FIG. Explanation of symbols, 1... Air cleaner, 2...
...Intake pipe, 3...Main combustion chamber, 4...
Swirl chamber, 5... Glow plug, 6... Injection nozzle, 7... Injection pump, 8... Exhaust pipe, 9... Throttle valve. , 10... diaphragm valve, 11... EGR valve, 12, 13...
・Solenoid valve, 14... Vacuum pump, 15.
・・・・・・Constant pressure valve, 16・・・・・・Batute l8 17・
... Glow relay 18 ... Servo circuit,
19... Glow lamp, 20... Accelerator position sensor, 21... Crank angle sensor, 2
2$-1 Neutral switch, 23...Vehicle speed sensor, 24...Temperature sensor, 25...Lift sensor, 26...Atmospheric density sensor, 27...
...Arithmetic unit, 28...CPU129...
ROMl3O...RAMl3l...Input/output interface, 32...Entrance, 33...
... Drive shaft, 34 ... Feed pump, 35 ... Pressure regulating valve, 36 ...
・Pump room, 37... Suction boat, 38...
...High pressure plunger pump, 39...Plunger, 40...Eccentric disc, 41...
...Joint, 42...Face cam, 43
... Condolences - Raling, 44 ... Laura, 4
5...Distribution boat, 46...Delivery valve,
47...Driving pin, 48a...
・Orifice, 48...Plunger, 49...
... Cylinder, 49a ... Orifice, 49a
...Passage, 50 ...Casing, 50
a... Passage, 51, 52... Oil chamber, 50
b... Orifice, 53... Fuel passage, 54
... Solenoid valve, 55 ... End high pressure chamber, 56 ...
... Passage, 57 ... Low pressure chamber, 58 ... Spring, 59 ... Spill port, 60 ... Sleeve, 61 ... Plunger pump chamber, 62 ...
... Servo motor, 63 ... Axis, 64.
・Slide element, 65...Link lever, 66...
・Zen, 67... Fulcrum, 68... Potentiometer, 69, 70... Gear, 71...
・・Fuel cutoff valve, 72・Zebot pin, 101・・・・
- Deviation detection circuit, 102... Control circuit, 103...
...Injection timing control mechanism, 104...Sensor, 1
05...Counter, 106...DA converter, 107...Target value calculation circuit, 108...
・Differential amplifier, 109...variable time constant integrator,
110...Dither oscillator, 111...Comparator, 1
12... Absolute value circuit, 113, 114...
Comparator, 115, 116... switching circuit,
117... Arithmetic amplifier, 118... Change speed detection circuit, ISl... Accelerator position signal, IS2
...Reference pulse, IS3●●●◆●● unit pulse, IS4ll neutral signal, IS5...
Vehicle speed signal, IS6...Temperature signal, IS7...
...Injection start signal, IS8...Atmospheric density signal, IS9...Sleeve position signal, ISLO...
...Battery voltage signal, ISll...Starter signal, IS12...Glow signal, 0S1...
... Throttle valve opening control signal, 0S2... EGR control signal, 0S3... Fuel cutoff control signal, 0S4...
...Fuel injection amount control signal, O ■ ... Injection timing control l signal, 0S6 ... Glow control signal, 0
S7... Glow lamp control signal, S1...
...Servo signal.

Claims (1)

[Scope of Claims] 1. Means for detecting the actual value of the fuel injection timing, means for detecting the deviation between the actual value and the target value, an integrating means for integrating the deviation, and a means for detecting the deviation between the actual value and the target value, and a means for detecting the deviation between the actual value and the target value. a fuel injection timing control mechanism for controlling the fuel injection timing according to the invention; and a control means for changing the integration time constant of the integration means in response to the magnitude of the deviation or the rate of change of an operating variable related to the deviation. Fuel injection timing control device. 2. The fuel injection timing control according to claim 1, wherein the control means decreases the integral time constant as the magnitude of the deviation or the rate of change of the operating variable related to the deviation increases. Device. 3. The control means is configured to immediately output a signal of the maximum value or minimum value by setting the integral time constant to zero when the magnitude of the deviation or the rate of change of the operating variable related to the deviation is equal to or higher than a predetermined value. A fuel injection timing control device according to claim 1, wherein the fuel injection timing control device is characterized in that: 4 When using a device that controls the injection timing by controlling the duty of a solenoid valve as the fuel injection timing control mechanism described above, if a signal of the maximum value or minimum value is given, the duty is set to 100% or 3. The fuel injection timing control device according to claim 3, wherein the fuel injection timing control device is configured to keep the solenoid valve fully open or fully closed by setting the solenoid valve to 0%. 5. The fuel injection timing control device according to any one of claims 1 to 4, characterized in that the load amount of the internal combustion engine is used as the operating variable related to the deviation. 6. Claims 1 to 4, characterized in that the position of a sleeve for fuel injection amount control provided in an injection pump of a diesel engine is used as the operating variable related to the deviation. The fuel injection timing control device according to any one of the above. 7 Claim 1, characterized in that the position of the accelerator pedal is used as the driving variable related to the deviation.
The fuel injection timing control device according to any one of items 1 to 4.