JPS6060237A - Apparatus for controlling fuel injection timing - Google Patents

Abstract

PURPOSE:To control the fuel injection timing accurately, by providing an actual ignition timing detecting means for detecting the actual ignition timing in a combustion chamber in an electronic control means which produces a driving signal for controlling the fuel injection timing. CONSTITUTION:A fuel injection timing controlling apparatus of this invention comprises a group of sensors II for detecting the conditions of engine operation, an electronic control means III which produces a driving signal for controlling the fuel injection timing, and a fuel injection timing adjusting means IV for adjusting the fuel injection timing of a fuel injection pump. The electronic control means III includes an actual ignition timing detecting means V which detects the actual ingition timing in a combustion chamber. With such an arrangement, it is enabled to detect the actual ignition timing in a stable and correct manner and to control the fuel injection timing accurately against the change in the conditions of engine operation.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention 1j Controls the fuel injection time of diesel engines
Fuel injection timing tall device, Q! i, a fuel injection Q' that detects the actual ignition timing of the fuel in the engine combustion chamber and controls the fuel injection sword member so that the actual ignition timing becomes the target ignition timing according to the engine operating state; This relates to a one-time control device.

Conventionally, as shown in Japanese Unexamined Patent Application Publication No. 179346/1983 as a fuel injection timing till device for a Dale R-Q engine, each 1!1 is used to detect the operating state of the engine.
It calculates the target ignition timing based on the signals from these sensors, detects the actual ignition timing in the engine combustion chamber, and adjusts the fuel injection timing to match the actual ignition timing with the target ignition timing. There was a fuel injection timing control device that controlled the fuel injection timing of the pump.

By the way, in order to detect the actual ignition timing, an ignition sensor that detects combustion light or combustion pressure in the combustion chamber is provided, and the output signal level from the ignition sensor and a predetermined detection level are used. The actual ignition timing is detected by comparing the size of It was difficult to detect a stable actual ignition period in response to changes in . In other words, when the engine is idling, the ignition sensor's output signal is several tens of times higher than the sensor's output signal at high speeds and high loads, so for example, the detection level of the actual ignition timing mentioned above. If it is set to correspond to the ignition sensor output signal during idling, the sensitivity may become too high at high speeds and high loads, causing malfunctions due to noise etc., resulting in problems such as the inability to detect accurate ignition timing. On the other hand, if the detection level is set in accordance with the ignition sensor signal during high rotation and high load, problems may occur such as a detection delay or failure to detect during idling.

The present invention was developed in view of the above problems, and by setting the detection level of the actual ignition timing according to the engine operating condition, it is possible to detect the actual ignition timing stably and accurately against fluctuations in the operating condition. It is an object of the present invention to provide a fuel injection timing control device that can perform accurate fuel injection timing control in response to engine operating conditions.

The first configuration of the present invention that achieves this object, as shown in FIG. and a group of operating state detectors for detecting various operating states of the engine.
In response to the information from the operating state detector group H, the target ignition timing is calculated, the actual ignition timing is detected, and the drive for fuel injection timing control is performed to match the actual ignition timing with the target ignition timing. In the fuel injection timing control device, the fuel injection timing control device is equipped with an electronic control means (IV) that outputs a signal, and a fuel injection timing adjustment means (IV) that receives the output drive signal and adjusts the fuel injection timing of the fuel injection pump. By setting a detection level in the electronic control means (2) based on a signal from a sensor other than the above-mentioned ignition sensor (2) of the above-mentioned operating state detector group (2), and comparing the detection level with the signal from the above-mentioned ignition sensor (2). The gist of the present invention is a fuel injection timing control device characterized in that a real hole timing detection means V for detecting the actual ignition timing in a combustion chamber is provided.

An embodiment in which the fuel injection timing control device of the present invention is applied to a Bosch VE type distribution fuel injection pump will be described below with reference to the drawings.

FIG. 2 shows a block diagram of the present embodiment. In the figure, 1 is a crank angle sensor that generates a signal corresponding to the engine speed; 12 is an accelerator sensor that detects the amount of accelerator operation by the driver; 3 is an injection amount sensor that detects the fuel injection interval, and 4 is an intake pressure sensor 1 that detects intake air pressure.
5 is an intake air temperature sensor that detects intake air temperature; 6 is a water temperature sensor that detects cooling water temperature; and 7 is a fuel temperature sensor that detects fuel temperature.
'81 lens, 8 is a battery voltage detector for taking in the power supply voltage to the electronic control unit 10, 9 is an ignition sensor for detecting the actual hole timing, and each of these sensors 1 to 9 is used to detect the operating state. Vessel I! This corresponds to Y II. Further, 10 is a waveform shaping circuit 11, an ignition detection circuit 12, an A/D converter 13, a control circuit 14, and a drive circuit 1.
5-C1 waveform shaping circuit 11
The signal from the crank angle sensor 1 is sent to the ignition detection circuit 1.
The signal from the ignition sensor 9 is sent to the A/D converter 13, and the signal from the ignition sensor 9 is sent to the A/D converter 13. A large number of signals such as sr, etc. are input, and the waveform is shaped by the waveform shaping circuit 11. The Δ/D-converted people detection signal is input to the CPU 14a of the control circuit 14,
CPUI 4a, ROM 14b, R in the control circuit 14
The fuel injection timing with an appropriate duty ratio will be determined at AM14c. Then, a drive signal is outputted from the drive circuit 15 to the electromagnetic valve 21 of the hydraulic timer 20 in accordance with the calculated fuel injection timing in A, and the fuel injection timing is controlled. The electronic control device 1o corresponds to the electronic control means (2), and the ignition detection circuit 12 corresponds to the ignition timing detection means (V).

Next, the hydraulic timer 20 corresponds to the fuel injection timing adjustment means, and includes a solenoid valve 21, a timer piston 22,
It consists of a roller ring 23, a pump internal pressure chamber 24, a timer piston high pressure chamber 25, a low pressure chamber 26, a return spring 27, and the like. Further, 28 is a vane type fuel pump. The timer piston 22 is connected to a roller ring 23,
When the timer piston 22 moves to the left in the figure, the roller ring 23 rotates in the clockwise rotation direction, and the fuel injection timing changes to the advance side. The vane type fuel pump 28 is rotated by an unillustrated drive shift of the injection pump, and pressure-feeds the fuel 1 from the fuel tank to the pump internal pressure chamber 24. The fuel in the pump internal pressure chamber 24 is injected into the engine and is guided to the timer screw 1 hem high pressure chamber 25 through the throttle, and the pressure horn of the timer screw 1 hem high pressure chamber 25 and the force of the return spring 27 in the low pressure chamber 26 Since the position of the timer piston 22 is determined at the balanced position, the position of the J-ru ring 23 is determined and the injection timing is determined.

Here, the crank angle sensor I1 is proportional to the rotation speed and detected as the number of pulses by placing an electromagnetic pickup facing a gear-shaped inductor driven to the crankshaft of the engine, and in this embodiment, It is also used as a crank angle sensor 1 which generates a crank angle reference signal, so that 1292 rotations are outputted from the in cycle of the crank angle sensor 1 for the valve. In other words, this crank angle sensor 1 detects the rotational angular position of the crankshaft of the engine.
It has protrusions divided into equal parts, one of which is located 10~ before top dead center.
The voltage waveform at point a changes according to the pulled gear 1A and the magnetic flux change accompanying the rotation of gear 1A, as shown in Figure 4 (a).
), and an electromagnetic pickup 1B that generates an AC voltage signal Va as shown in FIG. Then, the alternating current voltage signal Va is processed by a known waveform shaping circuit 11 as shown on the right side of FIG.
is the crank angle standard (of period Tn) as shown in FIG.
The waveform is shaped into Ei and vb and output to the control circuit 14. The axle sensor 2 consists of a voluncimeter or a differential lance, and is designed to output a signal 19 corresponding to the axle operation.

As shown in FIG. 5, the injection quantity sensor 1) 3 includes a movable core 3Δ fixed to the spill ring 31 of the fuel injection pump via a lever, and two pairs of coils 3 wound around the outer circumference of a cylindrical bobbin.
B and the fixing screw 3 that fixes the sen υ body to the pump head.
When the core 3Δ slides through the two pairs of coils, the inductance of the coils changes. ) is intended to detect Im. The spill ring 31 is located to the left in the figure when there is little fuel nozzle Hfi, and moves to the right in the figure when there are many fuel nozzles Hfi. from,
When the fuel injection amount is large, the output voltage value VQ is 11°C,
For example, it is 1V, and on the other hand, when the injection amount is small as in the case of idling operation, the output horn voltage value VQ is operated to be, for example, 3V.

Next, as the intake pressure sensor 4, for example, a semiconductor pressure detector is applied. Furthermore, a thermistor can be used as the intake temperature sensor, water temperature sensor, and fuel temperature sensor, and the temperature is detected by a resistance value corresponding to each temperature.

Check the actual ignition timing using the detector 6 fire sensor 1) 9.
For example, a sensor that detects combustion light in the combustion chamber or a sensor that detects combustion pressure can be considered, but in this embodiment, an ignition sensor that detects combustion light and has a structure as shown in FIG. 6 is used. I will explain this. The ignition lens 9 as shown in FIG. It consists of a light guide 9B that guides up to the transistor 9Δ, and an external housing 9C that holds the phototransistor 9A and the light guide 9B.

The light guide 9B uses an optical fiber made of a light-transmitting material made of quartz glass, for example, formed into a rod shape, and its tip 9B1 is made to protrude from the housing 9C by about 1 to 5 [mm], thereby directing the combustion light inside the combustion chamber. J, which can be detected.

FIG. 7 shows the ignition sensor 9 installed in a superflow Naashiro diesel engine, where 41 is a cylinder head, 42 is a piston, 4.34J exhaust valve, 44 is a superflow chamber, and 45 is a fuel It shows the chanting nozzle. As shown in the figure, the ignition sensor 9 is screwed into the cylinder head 41 and has a tip protruding into the overflow chamber 44, and a light guide tip 9B.
J, where combustion light inside the combustion chamber is detected at 1, is fixed.

The electrical signal photoelectrically converted by the phototransistor 9A of the ignition sensor 9 as described above is input to the ignition detection circuit 12, where the waveform is shaped into a pulse offset representing the ignition timing and output to the C control circuit 14. However, this ignition detection circuit 12 is based on the present invention] There are two circuits (41 circuits) (which will be explained in detail next).

FIG. 8 is a circuit diagram showing the ignition detection circuit 12. As shown in the figure, the ignition detection circuit 12 includes a buffer amplifier 50 for amplifying the electrical signal from the ignition sensor 9, a detection level 59 for setting and overturning the detection level, a constant circuit 60, and a buffer amplifier 50.
The comparison circuit 70 compares the electric signal amplified by the detection level with the detection level set by the detection level setting circuit 60 and detects the ignition signal. /I I,: Output circuit.

Here, the buffer 7 amplifier 50 is a non-inverting amplifier circuit consisting of an operational amplifier 51 and a resistor 52.
Amplify the electrical signal photoelectrically converted by transistor 9△,
This circuit outputs the Dengetsu 7 signal Vc corresponding to the combustion light in the combustion chamber. The detection and setting circuit 60 is a differential amplifier circuit consisting of an A amplifier 61, resistors 62 to 67, and a capacitor 68.
This is a circuit that outputs a detection level signal Vd corresponding to a signal VQ from.

Further, the comparator circuit 70 is a comparator consisting of an A amplifier 71 and resistors 72 to 75, and is a comparator that includes a voltage signal VC.
This circuit outputs an ignition signal Ve which is "H" when the voltage signal VC is higher than the detection level signal \/d, and rLJ when the voltage signal VC is less than the detection level signal Vd.

Next, FIGS. 9(A) and 9(B) are diagrams showing the relationship between the voltage signal Vc detection level signal Vd and the ignition signal ve, where (A> is when the engine operating state is in the idle link state). In this case, (B) represents the case where the engine operating condition is high rotation and high load.As is clear from the figure, the voltage signal vC that goes to the high rotation and high load 11''T is idling.
, i is several tens of 18 times more intense than i, but this is because the amount of fuel injected into the combustion chamber increases and the combustion light becomes stronger.

In addition, the minimum voltage value of the voltage signal Vc at high speed and high load is much lower than that at idling, but this is due to the combustion of a large amount of fuel, the wall temperature of the combustion chamber, and the ignition ton. The tip of the housing 9C of No. 9 is red hot and heat rays, that is, infrared rays are generated even during combustion.
This is because the transistors 1 to 9A perform photoelectric conversion.

However, since the detection level signal V (, I) which is output from the detection novel setting circuit 60J is set to -C in accordance with the duty m as shown in FIG. The voltage signal that changes according to
As a result, the ignition timing Tj shown in FIG. 9 can be accurately detected.

Next, the waveform shaping circuit 11.1'l fire detection circuit 12,
Alternatively, various signals whose waveforms have been shaped by the A/D converter 13 are received, and the hydraulic tie is connected to the 1% control circuit 15. The processing operation of the control 311 circuit 14, which outputs a control signal with an optimal data-to-ti ratio in order to avoid outputting a drive signal for the drive filter 20, is shown in FIGS. 11 to 1/1). 1 ni l-di 1? -1~, and 7J' shown in Figure 15
4; Explain according to the i ff diagram.

11 represents the main routine of the control circuit 14. When the power is turned on and processing starts, initialization processing for subsequent processing is first performed at step 101. . In other words, the values of the learning correction duty ratio Do and the incorrect attachment correction duty ratio ΔD, which will be described later, are rOJ
will be subject to

In the subsequent step 102, the engine speed NE is calculated based on the signal from the waveform shaping circuit 11, that is, the crank angle reference signal from the crank angle sensor 1 as shown in FIG. , signals such as accelerator operation amount, fuel injection amount, intake pressure, intake temperature, cold N water temperature, fuel temperature, and panteri voltage are read, which are converted into digital signals by the A/D converter 13. It will be done.

In the next step 104, the engine speed calculated in step 102) (engine rotation speed NII) is calculated in step 103.
The basic duty ratio Db is determined based on the various data l+1 read in. The target basic duty ratio D11 is determined by using a map or 51 equation that uses the fuel injection IQ and engine speed NF determined according to the characteristics as shown in Fig. 15 as parameters. Ratio 1) I) is calculated using a map or calculation formula that uses battery voltage, fuel temperature, etc. as parameters.
The correction is based on the basic duty ratio Db.

After the basic duty ratio Db is calculated in step 104, the corrected duty ratio Dr is calculated in step 105. It can be determined by adding the duty ratio DO and the error correction duty ratio Δ1).

Next, in step 106, the target ignition timing is determined to be lower using a map or the like based on the various data (10) read in step 103, and the process moves to step 107.

In step 107, it is determined whether or not the ignition signal 0 representing the actual ignition timing is output from the ignition detection circuit 12, and if the ignition signal Ve is not output, then in step 107 the Idol signal is output. It is determined that step 10
8, and on the other hand, the ignition detection circuit 12 outputs the ignition signal Ve.
is output, it is determined as rYEsJ and the process moves to step 109.
If the ignition sensor 9 or the ignition detection circuit 12 is damaged or malfunctions, or if the engine misfires, Mooichishou Kenso becomes zero-)lζ
In step 108, the output duty ratio is set to t+ti of the corrected duty ratio]]1· determined in step 105, and the process returns to step 102.

In step 109, the actual ignition +ll] -I-1 is extracted based on the Kunk angle reference signal from the waveform shaping circuit 11 and the ignition signal Ve from the ignition detection circuit 12, and the next step 110 Then, the error T err between this actual ignition timing r and the target ignition timing -rb determined in step 106 is calculated.

In the following step 111 d3, the above K (difference Ter1
The absolute value of ゛ exceeds the predetermined value.
It is determined whether or not it is +. If the error T err is larger than the set value ToJ, it is determined in step 111 that it is rNOJ', and the process moves to step 112. On the other hand, when the error T err is larger than the set value ToJ
If it is within To-(J, rYEsJ is determined and the process moves to step 113.

When the process of step 112 is executed, the error “I'e+・
The error correction duty ratio △I] is determined based on r using a map or the fit0 formula, and in the next step 1'14, the error correction duty ratio △D and the correction duty ratio 1]1' determined in step 105 are calculated. The output duty ratio is calculated by

In step 113 d3, the same process as in step 108 is executed, and the ratio of the output duty ratio is the correction duty ratio 1).
Moving on to 15. And if you enter step 115,
1) A process in which the learning correction duty ratio -〇 〇 e '3 used when carrying out step 11i of step 105 in u is obtained, and the error correction duty ratio △D calculated in step 112 is rOJ set 4. is executed. still,
The learning correction decoding ratio Do is the difference 7') between the output duty ratio determined in step 113 and the Amagi duty ratio Db determined in step 104.

When the process of step 114 or step 115 is completed, the process moves to step 102 in the same way as step 108, and the process as described above is executed again. In this way, in this main routine, the target ignition timing and actual ignition timing are determined based on each signal, and the actual ignition timing is set to match the target ignition timing. The process to calculate and reverse the deco-ar ratio is performed.

FIG. 12 shows a timer interrupt routine that is processed for a certain period of time, that is, for each driving horn side cycle. A control signal corresponding to the output duty ratio determined in the routine is output to the drive circuit 15.

FIG. 13 shows an ignition interrupt routine that is processed every time the ignition signal VQ is generated by the ignition detection circuit 12. When the ignition signal Ve rises, the process of reading the fish timer tj shown in FIG. 9 is executed.

FIG. 14 shows a crank angle interrupt routine in which the crank angle reference signal Vbfo from the waveform shaping circuit 11 is processed, and the crank angle reference signal V11 shown in FIG.
The process of reading the timer grid of 1 point of Kari II' is executed.

When a control signal is output from the water control 11 circuit 14 to the drive circuit 15, the drive circuit 15 outputs the drive spring according to the control signal to the electromagnetic valve 21, and the hydraulic timer 20
The position of the roller ring 23 is determined, and the C injection timing is set. .

As explained above, in this embodiment, when the J3 (receives the f5 blade from the right fire tip 9) and the shield large detection circuit 12 detects the i1 fire signal Ve, the Since the detection is performed using a detection level determined according to the engine speed, the ignition timing can be accurately detected without being affected by fluctuations in engine operating conditions.

In this embodiment, the detection level is set by the voltage V (+) corresponding to the fuel injection Q.
It is also possible to set the accelerator opening voltage Vα corresponding to the signal from the axle sensor 2 as shown in the figure. Alternatively, the voltage VN may be set in accordance with the engine speed. However, when using the voltage VN corresponding to this engine speed, the crank angle reference signal output from the waveform shaping circuit 11 is converted into an analog voltage signal in order to use the signal from the crank angle sensor 1. It is necessary to add a known frequency-voltage conversion circuit (F/V conversion circuit). Furthermore, as shown in FIG. 17, two voltage signals Vq and VN corresponding to the fuel injection amount Q and the engine rotation vlNE are generated.
The detection level may be set using .

(Details above) As mentioned above, the fuel injection port of the present invention has a first phase limit of 0.
In the device, the detection level for detecting the actual ignition timing after receiving the signal from the ignition engine is set according to the engine operating condition. 1. It is stable against fluctuations in engine operating conditions and is accurate, making it possible to perform fuel injection timing control with a high product number corresponding to engine operating conditions. So, does fuel injection depend on engine operating conditions? J<i will be J-, so JJI gas,
It is assumed that 8 customers will be directed.

[Brief explanation of the drawing]

FIG. 1 is a block diagram of the present invention (J11 representing the configuration), and FIGS. 2 to 15 are J5 diagrams representing one embodiment of the present invention.
2 is an overall configuration diagram of this embodiment, FIG. 3 is a circuit diagram showing the crank angle sensor 1 and waveform shaping circuit 11, and FIG. 4 is a circuit diagram showing its operation. Fig. 5 is an explanatory diagram of the structure and operation of the injection amount Hinley 3, Fig. 6 is a sectional view of the main part of the ignition sensor 9 that detects the RR fire using combustion light, and Fig. 7 is a diagram showing the main part of the ignition sensor 9. ]-Injin Tori (jl't:
Figure 8 is a circuit diagram of the ignition sensor 9 and 6 fire detection circuit 12, Figure 9 is a mink chart showing its operation, and Figure 10 is a combustion chart. FIG. 11 is a flowchart showing the main routine in the control circuit 14, and FIGS.
Similarly, FIG. 4 shows the interrupt routine in the control circuit 14, and FIG. 15 is a diagram showing the relationship among the engine speed NE, fuel injection ff1Q, and target basic decoding ratio Dp. Further, FIGS. 16 and 17 show other embodiments, and FIG. 16 is a diagram showing a detection level signal Vd set corresponding to the accelerator opening voltage Vα.
FIG. 17 is a circuit diagram showing a setting circuit 60' in which the detection level signal Vd is set based on the fuel injection ff1Q and the engine speed NE. ■、9...Ignition sensor■...Operating status detector group■...Electronic control means IV...Ignition timing adjustment means■...Actual ignition timing detection means 1...Crank angle Sensor 3...Gage 104 Early sensor 11...Waveform shaping circuit 12...Ignition detection circuit 14...Control circuit 60...Detection level setting circuit fee Sokujin Benkaju Foot A'7 Tsutomu 11! I 1 person Figure 3 71 Figure 4 Figure 5 Figure 6 Figure 12 Figure 13 Figure 14 Figure 15 E --

Claims (2)

[Claims] (1) A group of operating state detectors that includes an ignition sensor that detects the ignition state of fuel in the diesel engine combustion chamber and that detects various operating states of the engine, and a group of operating state detectors that detect signals from the group of operating state detectors. electronic control means for calculating a received target ignition timing, detecting an actual ignition timing, and outputting a drive signal for Ill il control during fuel injection so that the actual ignition timing coincides with the target ignition timing; Fuel injection that adjusts the fuel #1 injection timing of the fuel injection pump in response to the output drive signal! )J period Fil! ! In the fuel injection timing control device, a detection level is set in the electronic control means based on a signal from a sensor other than the ignition sensor in the group of operating state detectors, and the detection level and the above-mentioned By comparing the signal from the ignition sensor, it was determined that the signal from the ignition sensor was compared with the signal from the ignition sensor.
111 + police 441 means (fire r characterized by having been set up)
tIa Kenshimei control l+ device. (2) The detection level is one or two of the following: a signal corresponding to the fuel JGl injection amount, a signal corresponding to 1 good accelerator opening, or a signal corresponding to 1 carrot rotation speed.
Feature I [Claim 1 t! ! I; Benefit timing control device.