JPS59183043A - Fuel injection timing controlling apparatus - Google Patents

Abstract

PURPOSE:To reduce the number of component parts by making common use of a means for detecting a reference turning angle position and a means for detecting the engine speed. CONSTITUTION:The timing at which combustion of fuel injected into a cylinder is started is detected by a fuel combustion detector 2b, and a reference turning angle position and the engine speed are both detected by a means 2a for detecting the reference turning angle position. The fuel injection timing is controlled such that the actual combustion timing detected by the combustion timing detector 2b is simultaneous with the aimed combustion timing detected by the means 2a. By employing such an arrangement, it is enabled to reduce the number of component parts.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a device for controlling the noise of a fuel control device in a diesel engine.

Conventionally, this type of injection atv I period control device calculates the actual combustion timing from a combustion timing signal from a combustion timing detector and a reference timing signal from a reference timing detector, such as in Japanese Patent Application Laid-Open No. 57-179346. Then, the injection timing is adjusted to correct the error between the target combustion timing and the actual combustion timing, which is calculated based on various signals from the operating condition detector that electrically detects operating conditions such as engine speed and injection amount. It has been proposed to electrically control the means.

However, the mouth seed device has a reference time detector installed separately (
Therefore, it is desirable to reduce the number of parts.

The present invention has been made in view of the above points, and replaces the rotation speed detector that detects the engine rotation speed, which has been previously used as an operating condition detector, with a reference timing detector (rotation angle reference position). The purpose of the present invention is to reduce the number of parts by using the detector as a detector, and also to solve the problems that arise when the detector is used as a detector. In other words, the present invention aims to reduce the number of parts, maintain sufficient accuracy of rotational speed data as a rotational speed detector, and change the variation width and reference timing based on various causes of the 1+11 signal during combustion. To prevent erroneous actual combustion timing data from being calculated based on the relationship with the cycle (rotation angle) of a signal, and to perform fuel injection most suitable for engine operating conditions.

Therefore, one aspect of the present invention is to provide an operating state detector 1 for detecting the operating state of a diesel engine 7, as shown in FIG. 1a.
, an injection timing adjustment means 5 that adjusts the injection timing of the fuel on-pump 6, and a combustion timing detector that generates a combustion timing signal every time the fuel injected into the cylinder of the engine 7 starts to burn. 2b and a rotational angle reference position detector 2a which generates a position signal every predetermined rotational angle θN of the engine 7, which also serves as an engine rotational speed detector;
The target combustion timing O8 is determined based on the detected signal G of the operating state detector '1, and the injection is performed to correct this error according to the error between the target combustion timing O3 and the actual combustion timing θp. an electric control means 4 for controlling the timing adjustment means 5, and the rotation angle θN is set in advance so that the relationship θN>△01] is satisfied with respect to the variation range Δθp of the actual combustion timing θp recorded on the ship. This is a fuel wA river bend control device characterized by:

Another aspect of the present invention is to reduce the number of parts in a device that detects the injection timing and controls the injection timing, as well as to use the reference timing detector as a rotational speed detector. By doing so, while maintaining the accuracy of the rotation speed data, it is possible to prevent incorrect actual injection timing data from being calculated based on the relationship between the change width of the injection timing signal, the base time, and the period (rotation angle) of the lQ signal ε. The purpose is to prevent this from occurring, and to perform fuel injection that is optimal for the operating conditions of the engine.

For this reason, other aspects of the present invention include an operating state detector 1 for detecting the operating state of the diesel engine 7, and an injection timing adjusting means for regulating the injection period of the fuel injection pump 6, as shown in FIG. 1b. 5, a pre-injection detector 8 which generates an injection timing signal every time fuel is started to be injected into the cylinder of engine 7; An actual injection timing detector consists of a rotation angle reference position detector 2a that generates a reference position signal for each rotation angle θ-, and a target injection timing θ-S is determined based on the detection signal of the operating state detector 1. and electric control means 4 for controlling the injection timing adjusting means 5 to correct the error in accordance with the error between the target injection timing θ'S and the actual injection timing θ'p; and the rotation angle ON is the actual injection timing θ'p.
This fuel injection timing control device is characterized in that it is set in advance so that the relationship θN>Δθ′p is satisfied with respect to the variation width Δθ−p.

The present invention will be described below with reference to the drawings from FIG. 2 onwards.

2 to 8 show an embodiment of the first invention.

FIG. 2 is a block diagram showing the overall configuration of this embodiment, and the symbols 1.2a, 2b, 3.4.5.6.7 in the figure
correspond to those indicated by the same reference numerals in FIG. 1a, respectively.

The operating state detector 1 detects the rotational speed of the engine, the amount of injection into the engine, the intake pressure and intake air temperature for determining intake air tightness, the engine cooling water temperature, etc., and generates an electric signal.

The rotation angle reference position detector 2a is connected to the crank shirt 1 of the engine.
It generates a reference position signal every constant rotation angle period θN, and also serves as the engine rotation speed detector. The combustion timing detector 2b is located inside the cylinder of the engine. The timing at which the injected fuel actually starts to burn is detected by the light generated during combustion, and together with the rotational angle reference position detector 2a, constitutes an actual combustion timing detector 3. The electric control means 4 uses the detection signal from the operating state detector 1 as a control parameter to calculate the optimum injection timing target value for the engine, that is, the target combustion timing θS, and also calculates the detection signal from the actual combustion timing detector 3. (Actual combustion timing θp is calculated by No. 1, and an electrical output is sent to the injection timing adjustment means 5 to reduce the error to Oh according to the error of the actual combustion timing Op with respect to the target combustion timing θS. The injection timing adjustment means 5 is an electrical control means 4
The fuel injection timing of the injection pump 6 is adjusted with respect to the reference position signal.

In the operating state detector 1, it is possible to detect the number of pulses proportional to the rotation speed by placing an electromagnetic pickup facing a gear-shaped inductor stationary on the crankshaft of the engine. It is calculated from the period of the position signal.The amount of fuel injected into the engine 7, that is, the injection amount, is detected by the injection amount sensor 15, and specifically, the position of the fuel adjustment part of the fuel sniffer pump 6 is determined by It is detected as an electrical signal by a detector.A potentiometer or differential transformer can be used as a position detector.
Yes I! r, 1 jin 8 which is proportional to the river suspension is 1'1. As the intake pressure sensor 18 for determining the amount of intake air, a semiconductor pressure grating can be used, and as the intake air temperature iL sensor 17, a beam mister or the like can be used.

Further, the rotational angle reference position detector 2a of the link 7 has a stationary inductor disposed on the crankshaft, detects the reference position with an electromagnetic pickup, and obtains a reference position signal. This reference position (the im number is also used as a rotational speed signal. Fig. 3 is a sectional view of the main part of the distribution type combustion angle pump to show one example of this. 21 is a roller ring. 22 is a face cam, which is rotated by a drive shaft 27, rotates a plunger t-24, and is injected into the cylinder in the span 7 from a nozzle 29 for reciprocating the combustion I in the axial direction (two reciprocating movements). 15 (J is an injection lens that generates an electric signal according to the spill ring position and detects the injection amount. 26 is a crank shirt (・inductor for detecting the rotation angle, and is installed in the dry shaft 17 and the fixed,
It rotates in sync with the engine crankshaft. An electromagnetic pickup is used as the rotation angle reference detector,
A reference position signal is generated every 08 degrees of rotation angle of the engine with reference to the position where the engine rotation is TI) C (top dead center), 0 degrees off-center. For this purpose, inductor 2
6 is formed with 2×36010N convex portions, and the reference position signal sent to the 00 degree A face 1 on the electromagnetic pickup t3 is fixed at a position (10).

An embodiment of the combustion timing detector 2h is shown in FIG. In this example, A1 to 1 are used as photodetecting elements.
- Uses transistors. Reference numeral 10 denotes a cylinder head of one cylinder, which is provided with a screw hole into which a photodetecting element can be removed. Reference numeral 11 indicates a housing, and reference numeral 12 indicates a fiber plate 7 through which combustion light can pass, which is sufficiently resistant to vibration and heat, and is fixed to the housing 11. 13 is an electrically insulating plate to which a phototransistor 14 as a photodetecting element is attached, and 14a and 14b are its electrodes.

Fuel is injected into the combination firing chamber, and when the combustion completes (!11), the combustion light of A passes through the emitter 12 and reaches the transistors 1 to 14, and the combustion electricity No. 43 approaches between the electrodes 14'a and 114b. This is the combustion time of 18 yen.

Next, regarding the injection timing adjusting means 5, a case will be described in which the present invention is applied to a Bosch type fuel olfactory pump. Fifth
The figure is a cross-sectional configuration diagram of essential parts of a Bosch distribution fuel injection pump. The timer piston 51 is connected to the roller ring 21 by a lever 54, and when the timer piston 51 moves to the left in the figure, the roller ring 21 rotates in the clockwise rotation direction.
The fuel 1 injection timing changes to the advanced side. 55 is a vane type fuel pump, and I! The fuel tank 58 is rotated by the drive shirts 1 to 27 (Fig. 3) of the fuel pump.
The fuel is fed under pressure to the pump internal pressure WA. Reference numeral 56 denotes an overflow check valve, which prevents an excessive rise in pressure to the pump internal pressure chamber.

The pressure inside the pump and the fuel in the chamber A are injected into the engine and are guided to the timer piston high pressure chamber B through the throttle. Therefore, since the position of the timer piston 51 is determined to a position where the pressure in the timer piston high pressure chamber B and the force of the timer piston return spring 52 in the low pressure chamber C are balanced, the roller ring 2
1 position is determined and the injection timing is determined. Reference numeral 57 is a pressure regulating valve which controls the pressure in the timer piston high pressure chamber B by changing the opening/closing time ratio by changing the 0N-OFF ratio of the drive pulse from the electric control means 4. Determine the position, that is, the injection timing.

As shown in FIG. 2, the electrical control means 4 has a built-in microcomputer whose main elements are a central processing unit 1 to (CPU) 41, a memory (ROM) 44, and a memory (RAM>45), and controls the rotation angle reference position. A waveform shaping circuit 42 that shapes the output signal of the detector 2a and the output signal of the combustion timing detector 2b, an A/D converter 43 that A/D converts various analog input signals from the operating state detector 1, and CPU4
Amplifying the pulse output signal from 1, injection timing adjustment means 5
1 drive circuit 46 that obtains an electrical signal that enables driving the
Equipped with

The electrical control means 4 includes a rotation angle reference position detector 2a that detects the engine speed, an injection amount sensor 15 that indirectly detects the amount of OA, and a cooling water temperature sensor +J1 that detects the warm-up state of the quantity.
6. Input the intake temperature sensor 17 for detecting the air temperature taken into the engine and the intake pressure sensor 18 to each detector 8 indicating the operating condition, and set the target combustion timing most suitable for the engine operating condition. At the same time, the error between the actual combustion timing calculated as described later and the target combustion time + II] is determined, and the amount valve time of the pressure regulating valve 57 is changed according to this error value. By controlling the pressure of B, the timer screw 1-51 is moved and the injection timing is feedback-controlled.

Next, the method for calculating the actual combustion timing is shown in Figure 6. -1~ recite 12 words. (a) is the output waveform detected by the electromagnetic pickup of detector 2a, which sets the crankshaft rotation angle position as the rotation angle reference position.
In this embodiment, a four-cylinder, one-engine case is illustrated. This signal (a) is the engine rotation angle king DC (
Occurs every OH degrees with a position offset by 00 degrees from the top dead center (top dead center) position as a reference. (b) is a signal obtained by waveform shaping the output signal (a) of the rotational angle reference position detector 2a in the waveform shaping circuit 42. (C) detects the combustion timing! i
FyrI~ used as a photodetection element of the baking time detector 2b
This is the output signal of the transistor, and detects when fuel is injected into the gas chamber and begins to burn. (d) is an output waveform obtained by shaping the output signal of the combustion timing detector 2b by the waveform shaping circuit 42.

The signals (b) and ((1) above are applied to the input port of the CPU 41 to calculate the actual combustion timing. In the embodiment shown in FIG. 6, the above θN is 45 degrees, and the engine crank shirts 1 to 2 An example of an actual flow in which the combustion timing signal <C> occurs once during rotation is shown below.

If a Washi-chip microcombicoater is used as the microcomputer, CI) U41, memory ROM44, and memory RAM45 are constructed in one chip in the circuit block diagram of FIG. For example, the circuit MBL6801 W 2 manufactured by Fujitsu Ltd. can be applied, and in that case, the rotation angle base 4 (position detector 2a
In order to apply the waveform-shaped output signal @ (b) of the input capture register #1 to the input capture register #1, and the waveform-shaped output signal (d > of the combustion I'll detector 2b) to the input carburetor register #2. It is possible if the configuration is correct.

Assume that the rotation angle reference position detector 2a is offset to the advance angle side by 00 degrees with respect to TDC as shown in FIG. 6, and the time when the signal (d) is generated is expressed as tn(i),
This time tr+(i>immediately after signal (1)) generation time is t
t N
l-+), the actual combustion timing Op is the signal (I])
'l T n and T
N is Tn = tN(i) - tn('i > , T
N = ts(i)-tFJ-+) and calculated from the following formula Op-θN XTn/Ti-0o. Here, Op in the case of Op>O is (
As shown by Δ), it is calculated as an advance angle value of 00 degrees with respect to DC, while Op in the case of θp<0 is calculated as a retard value of 1 Op 1 degree, as shown in (B) in Figure 6. be done. Note that the actual combustion timing θp that can be calculated here must be within a range that satisfies -θO≦θp<ON −〇〇. This is because, if Op can exist in the range θp≧θ(to)−〇〇, it will advance by θNrCi with respect to the actual TDC of one prefecture, as shown in (C) in Figure 6. Shifted and wrong (TDC) θ1 based on point ′]
is calculated, and the case where Op may exist in the range Op - θO is also not shown, but Op based on the point θi deviated from the actual TDC < TDC) is r (
``(TDC)'' or ``(TDC)''
This is due to the fact that it is impossible to identify whether the calculation is based on points or not. Furthermore, the rotation angle reference position detector 2a is
When set to the advanced side by 00 degrees with respect to DC, the actual combustion timing θp is Tn', which is the same as in the case described above.
From TN, it is calculated as 61p-ONXTn/TN+θ0 degrees, and if the relationship 00≦θp θN+00 is not satisfied, it will not be considered as the regular actual combustion timing. Therefore, if the range of change in the actual combustion timing θp is Δθp, θN must be set so that Δθp<θ . Therefore, the adjustable range Δθ of the l111 adjusting means 5 at the time of injection is also ΔQ1. It is a necessary condition that it is set so that +<θN. Note that the offset θ0 can be arbitrarily set as 1 to 1 on the retard side and advance side of the range required for control (ihi). For example, θo = 3 degrees on the advance side, θN = 45 degrees, the range in which the actual combustion timing θ1] can be calculated is 13 degrees≦Op<42 degrees, which is a practically sufficient actual combustion timing detection range.

Next, the operation of the apparatus having the above configuration will be explained using flowcharts 1 to 1 shown in FIG. In step 101, in order to calculate the engine speed 1F7i number NE, the period of the signal from the rotation angle reference position detector 2a is set to N'E = 60/
[THX <, 360/θN)] Find rI+m. Here, θN is desirably set to θH≦90 degrees in order to provide sufficient responsiveness and accuracy to the detected engine rotational speed, and as described above, 0N-45 degrees is an appropriate value. In step 102, an engine operating state signal is read.

That is, the spill position as the injection amount sensor 15 is determined by the injection amount signal from the sensor, the water temperature signal from the engine cooling water temperature sensor 16, the intake temperature signal from the intake air temperature sensor 17, and the intake pressure signal from the intake pressure sensor 18. The A/D converter 43 performs A/D conversion, and the data is stored in the corresponding RAM 45. In step 103, a known four-point linear interpolation is performed from the two-dimensional map of the basic combustion timing based on the engine rotational speed N days and the injection size to determine the basic combustion timing. Figure 8 shows an example of the basic combustion timing map. OQT is the injection amount, tm
This is data on the basic combustion timing when n falls on the grid point.

Next, the intake air density is corrected based on the intake pressure and the intake air temperature, and the water temperature is corrected based on the engine cooling water temperature to determine the target combustion timing θS.

In step 104, the actual combustion timing θp is calculated from the rotational angle reference position signal and the combustion auxiliary timing signal using the method described above. In step 105, an error θεItR-θS-θp is calculated from the target combustion timing θS obtained in step 103 and the actual combustion timing θp obtained in step 10'/I. In step 106, it is determined whether the error calculated in step 105 is positive or negative. If θS>θ0, θggg>0,
Jumping to step 109, the -5 duty ratio is increased and the pressure is increased to il! l 'M': Increase the OFF time of the valve 57 and move the positions of the 4-C timer screws 1 to 51 to the advance side. Also, if θS<θp, Ot4<O,
The process jumps to step 108, and the duty ratio is decreased, the OFF time of the pressure regulating valve 57 is decreased, and the positions of the timer screws 1 to 51 are moved in the μ direction. For eS-θp, θ
gg = o, and the duty ratio is the same as the previous time (1 is output).If the actual value θp is still behind the target value θS, the regulating valve 57 lengthens the OFF time and sets the timer screws 1 to 1. The pressure of the high-pressure air 13 is reduced, and the timer screws 1 to 51 are moved to the advance side to advance the combustion timing, that is, the injection timing, and match the target value.Hereafter, steps 101 to 109 are performed for each pressure regulating valve control cycle. Repeat.

It should be noted that various structures other than those described above can be used as the combustion timing detector 2b. Next, other aspects of the present invention will be explained.

FIGS. 9 to 12 illustrate an embodiment of this second invention! ,: Figure 9 is a block diagram showing the overall configuration, and Figure 10 is a combustion timing detector according to the first invention. 11 is a schematic cross-sectional view of the main parts of the injection pump showing the injection timing detector to be replaced with t, FIG. 11 is a time chart A-- for explaining how to calculate the actual injection timing, and FIG. 12 is an electrical A flowchart for explaining the processing by the control means is shown.

As is clear from a comparison between FIG. 9 and FIG. 2, the overall configuration of this embodiment is different except that an injection timing detector 8 is provided in place of the combustion timing detector 2b. , the rotational angle reference position detector 2a@Ui is also used as a rotation error detector, and other points of the configuration are the same. Here, the injection timing detector 8 is activated as shown in FIG. An electromagnetic pickup such as a detection sensor 9- is used to detect the amount of fuel in the ring seat 23, and when the plunger 24 starts distributing and pumping the fuel, it is detected as shown in FIG. 11(C). Generates an injection timing signal. The other components of d3 in the +7λ pump shown in Figure 10 are the same as those in the injection pump shown in Figure 3.The injection timing detector 8 is as follows: other,
A piezoelectric element may be used to detect pressure changes in the fuel injection assist.

Still actual combustion 1v] Actual injection n instead of calculating DI)!
Regarding the sieving method for J period θ'p, a) Comparing the time chart of Fig. 11 and the time chart of Fig. 6, it is clear (the actual injection period θ'p is above). Combustion timing θ
1], depending on the offlet value θO, -(, /J-p
-θo x Tn /-'TN-00, or (yoθ'
1] - θ0XTII/TN +00, and the above-mentioned rotation angle θ with respect to the change width △O-p of the actual injection timing θ'p.
H needs to be set so as to satisfy the relationship Δθ′p<θ8. In addition, in Fig. 11, ('jru(a >, (
1)) is the same as (a) and (1)) in Fig. 6, and Mano ζ (-d) is the waveform of After shaping (this is the iE number).

Furthermore, the processing by the electric control means is as shown in FIG. 12, in which the target injection timing θ'S is calculated in step 103'C2 in the figure, and the actual injection timing θ' is calculated in step 104-. 0 is output, but step '10''
M, Ko02-1103-1104', 105", 106
-1107-,. 108-1109' represent steps 101 and 1 in the flowchart of FIG. 7 described above, respectively.
02.103.104.105.106.107.10
8.109, and similar processing is performed.

As explained above, the present invention allows the rotation angle reference position detector to be used also as the feeder rotation fault detector, and also to prevent incorrect actual combustion port, 51U1 data, or actual injection timing data that may occur due to the use of the rotation angle reference position detector as the feeder rotation fault detector. Since separation is prevented and engine speed data is maintained sufficiently accurate, it is possible to reduce the number of parts and achieve optimal fuel injection.

[Brief explanation of the drawing]

FIG. 1a is a basic configuration diagram of the first invention, FIG. 1b is a basic configuration diagram of the second invention, FIGS. 2 to 8 show an embodiment of the first invention, and FIG. The overall configuration is shown in the table (Wazu block diagram, Figure 3 is a schematic sectional view of the main parts of the injection pump, Figure 4 is a sectional view showing the combustion 1t:'i lvl detector and its installation state, Figure 5 is the injection pump) Fig. 6 is a timing chart explaining the method of calculating 1%l during actual combustion, Fig. 7 is a flowchart showing the processing by the electric control means, and Fig. 8 is the basic combustion timing 2. 9 to 12 are diagrams showing the main parts of an embodiment of the second invention, and FIG. 9 is a reblock diagram showing the overall configuration. Fig. 10 is a schematic cross-sectional view of the main parts of the injection pump showing the injection timing detector and its "A" state, Fig. 11 is a timing diagram illustrating the calculation method of 1V during actual injection, and Fig. 12 is is a flowchart showing the processing by the electric control means. 1...Operating state detector 2a...Rotation angle reference position west detector 2b...Combustion timing detector 3...Actual combustion timing Detector 4...Electrical control means 5...Injection timing adjustment means 6...Injection pump 7...Engine (diesel engine) 8...+111 during injection Detector 9...Actual injection timing detection 3rd page 71＼ 4th page 50th 80th N・-・ N, N,,・ N5゜26

Claims (1)

[Scope of Claims] 1. An operating state detector for detecting the operating state of a diesel engine; an injection timing adjustment means for adjusting the injection timing of a fuel injection pump; Actual combustion consists of a combustion timing detector that generates a combustion timing signal at each timing, and a rotation angle reference position detector that also serves as the engine rotation speed detector and generates a reference position signal at each predetermined rotation angle θN of the engine. A target combustion timing θS is calculated based on the detection signal of the timing detector and the operating state detector, and the target combustion timing θS and the actual combustion timing θp detected by the actual combustion timing detector are calculated.
and an electric control means for controlling the injection timing adjusting means to correct this error according to the error between the rotational angle θH and the actual combustion timing θp.
A fuel injection timing control device characterized in that the following relationship is satisfied with respect to p: θN>Δθp. 2. The fuel injection timing control device according to claim 1, wherein the adjustment width Δθ of the injection timing adjusting means satisfies the relationship that θ8 is Δθ flashing with respect to the rotation angle θ8. 3. An operating state detector for detecting the operating state of the diesel engine, an injection timing adjusting means for adjusting the injection timing of the fuel slant injection pump, and an injection timing adjusting means for adjusting the injection timing of the fuel injection pump into the cylinders of the engine. an actual injection timing detector consisting of an injection timing detector that generates a signal and a rotation angle reference position detector that also serves as an engine rotation speed detector and generates a reference position signal every predetermined engine rotation angle θ8; A target injection timing θ'S is calculated based on the detection signal of the operating state detector, and the target injection timing θ-3 and the actual injection 11
and electrical control means for controlling the injection timing adjustment means to correct the error in accordance with the error from the actual injection timing θ'p detected by the 11th-stage detector, and adjusting the rotation angle θH. A fuel injection timing control device characterized in that the fuel injection timing control device is set in advance so that the relationship θN>Δθ−p is satisfied with respect to the variation range Δθ′p of 1111θ′p during long injection. 4. The fuel injection timing control device according to claim 3, wherein the adjustment range Δθ of the adjustment means 111 satisfies the relationship of 80, × θ− with respect to the rotation angle θ8. .