JPS6030450A - Fuel injection timing regulating device for internal- combustion engine - Google Patents

Abstract

PURPOSE:To prevent the occurrence of variations in product quality and any influence attributable to a secular change or the like, by conducting detection by detectors at both driving and driven sides of an actuator, while detecting the actual injection timing of fuel on the basis of phase difference calculated by a time lag being compensated by a reference value. CONSTITUTION:During engine driving at an engine speed n1 and a rack position R1, if injection timing is theta deg., a sine wave in frequency proportionate to the engine speed N1 is converted into a pulse train and inputted into an A terminal of a microcomputer 34 from a detector 2 at the driving side while another pulse train obtained out of a detector 3 at the driven side is inputted into a B terminal of the said computer. And, a value T1 of a free run timer is read out by the pulse to be inputted into the A terminal and stored in an An address, and when a pulse is inputted from the B terminal as delayed at time t, a value T2 of the free run timer is stored in a B address, then a value T3 to be inputted into the A terminal again is stored in an An+1 address. Next, the N1 is found on the basis of these T1 and T3 values, reading out the data R1 from a circuit 38, and desired injection timing t'1 is calculated whereby the t1 is calculated from a difference between T1 and T2, and t''1 is calculated from a time lag in a cam of theta+0, making it the actual injection data and, after calculating error time t upon comparison between these t'' and t', spark delay or advance timing control takes place.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention provides a fuel injection system (IJJ) for an internal combustion engine that activates the fuel injection timing of the internal combustion engine and detects it based on the time difference between detection signals obtained from two detectors attached to an eta (timer).
FR#] This relates to the adjustment device.

Conventionally, as in Japanese Patent Application Laid-open No. 57-140530, the actuator for adjusting Ill in case of combustion angle was removed overnight (!J
The later method of detecting the fuel injection timing based on the time difference between the detection signals from two detectors is shown in Figure 1 (
As shown in b), for example, the signal of the driven side detector of the acticoator is waveform shaped to 1!7. The pulse signal synchronized with the engine rotation obtained by
In other words, based on the difference between the rising and falling times of these pulse signals a and b, that is, the magnitude of the time difference t shown in FIG. This time difference t and the advance angle of the fuel injection period can be detected. 1θ is the first value when the engine speed is constant.
They have a relationship as shown in Figure (b).

However, with this scale, if the mounting number of the driving side detector or the driven side detector is incorrectly positioned, and the hydraulically driven fuel injection timing adjustment device r as shown in Fig. 3, For example, in the case of an IC in which the time difference (which should originally be 0) becomes 11 due to a retardation failure (return failure) due to increased oil viscosity at low temperatures, etc., the injection timing advance amount θ-〇cam is actually However, this may be detected as a deviated value, and the detected injection timing is slightly different from the actual injection +!
The present invention has been made in view of this point, and the position of the drive-side detector or driven-side detector is fixed at the position of the actuator. [I B] If the position is different from the one that should be installed due to work or product variations in the detector, etc., that is, if there is variation between individual products and detection is performed by each individual product (if L4 does not match, or The purpose of this is to accurately detect the actual injection timing and optimize the fuel injection timing even if the detection signal becomes inaccurate due to changes in the detector over time.

Embodiments of the present invention will be described below with reference to FIGS. 2 to 8.

FIG. 2 is an overall configuration diagram of the apparatus of the present invention, where 1 is a fuel injection pump, 1' is an actuator for adjusting the injection timing of the fuel injection pump 1, and is driven by hydraulic pressure, for example.
2 is an electromagnetic drive side detector attached to actuator 1', 33 is an electromagnetic driven side detector also attached to actuator 1, and 4 is an engine negative sensor. 5 is an electric control circuit, which includes a negative injection timing detector 5, a pulse signal for driving the injection timing a9 determining means 6, the actual injection timing detecting means 7, and the actuator 1. The target injection 1'JJ stage setting means 6 receives signals from the drive side detector 2 and the load detector 4, and sets a target injection 13J according to the operating state of the engine. '＋
11lJ, the actual injection timing detection means 7 receives the signals from the driving side detector 2 and the driven side detector 3. The means 8 generates a pulse signal for driving the pressure control valve 9.10 of the actuator 1' depending on the difference between the target injection timing and the actual injection timing.B force control valve 9.
The actuator 1- is driven in accordance with the hydraulic pressure adjusted by J- to the drive of the fuel injection pump 10, and the injection timing of the fuel injection pump 1 is adjusted.

Next, FIG. 3 is a sectional view taken along the central axis showing the detailed configuration of the hydraulic actuator 1'.A flange 13 is fixed to the fuel injection pump 1 with bolts 12, and a hydraulic chamber 14 is provided, and a hydraulic screw 15 is made movable in the axial direction by the pressure action of the fluid flowing into the hydraulic chamber 14.

The hydraulic piston 15 is provided with an inclined surface 16, and the inclined surface 16
A shifter 17 that faces and contacts the radially slidable shifter 17 is disposed, and since the shifter 17 is connected to the eccentric shaft pin 18 of the eccentric cam, the radial movement of the shifter 17 causes a small eccentricity. The cam 20 is rotated, and the eccentric cam 19
Change the phase of the hub 22 (driven part) that accommodates 1!
It is configured in such a way that it can be On the other hand, the hub 2
2 outer peripheral part 23 and cover 24 (one component of the drive member)
The cover 24 is rotatably fitted to the end cover 25 in which the driving bin 21 is installed.
-26, and is integrally constructed with the end cover 25.

In the above configuration, drive-side uneven portions 27 are formed at equal intervals on the outer circumference of the cover 24, which is a drive-side rotating member that rotates integrally with the drive shaft of the engine, and furthermore, the flange 13 is provided with bolts 2.
The bracket 29 fixed at 8 is arranged, and the bracket 29
The rri magnetic type drive side detector 2 is screwed into the drive side detector 2 and faces the drive side uneven portion 27 . Furthermore, the bracket 29 has an elongated hole that is movable along the rotational direction of the cover 24 with respect to the flange 1S.

Also, the fuel injection camshaft 30 on the driven side and the key 31 are used to control the position 'I!'. ! Nazuhashi 2 to determine the driven side rotating member
2 has the same number of driven side uneven parts 32 as the driving side uneven parts 27 of the cover 24, and is opposed to the electromagnetic type driven side detector 3 screwed onto the flange 13.

Next, FIG. 4 is a diagram showing details of the IC electrical control circuit 5 shown in FIG. The signal is shaped into a waveform that the C microcomputer 34 cannot handle (FIG. 1(a) a, b), and is input to the microcomputer 34. Reference numeral 35 denotes a rack position r detector, which corresponds to the load detector 4 and detects the engine load at the rack position of the fuel injection pump 1 control 1] - the rack position. 37G is an oscillation drive circuit for driving the detector 35, a detection circuit for detecting the signal from the rack position detector 35 and generating a DC voltage corresponding to the rack position, and 38 is a Δ/D conversion circuit. , converts the analog signal from the detection circuit 37 into a digital signal and inputs it into the micro-combiner 34. Further, the micro-1 processor 34 includes a ROM, a RAM, and a processor (N7 function) internally, and a drive circuit 39 connected to the output of the micro-computer 34 amplifies the signal from the micro-computer 34 with current. Pressure horn control valve 9
．． 10 is driven. Then, one pressure control valve 9.1o is installed on the oil inflow side and one on the oil outflow side), and the amount and valve time of each valve is controlled m-4 based on the output signal of the microcomputer 34. J:-C Adjusts the oil pressure and controls the 1ljl timing.

Next, the operation of the microcomputer 34 will be explained based on the flowchart of FIG. 5i.
0 returns the computer's internal memory, input/output board, etc. to the initial state. Next, in step 101, the relative positions of the driving side detector 2 and the driven side detector 3 are detected,
Write down this value (time difference) in g5. In step 102, steps 108 to 10 of the interrupt routine shown in FIG.
Rack 4D of a control rack (not shown) subtracts the engine speed based on the data obtained in Step 9 and increases or decreases fuel injection through the FA/D conversion circuit 38 in Step 103
# Input Q and then in step 104
Engine speed decremented by 02 and Stella 7' + 03
("Due to the damaged rack position n, the target injection 01 n,'
The performance of the r period will be performed. Step 105 uses the value obtained in the interrupt routine shown in FIG. 6 and step 101r+! 7 (actual injection timing is falsified based on t+, Stella 710
In step 6, the target chant +i1J obtained in step 104 is compared with the actual 117'1 copper time obtained in step 105, and the pressure control valves on the inflow and outflow sides of the hydraulic pressure are adjusted according to this difference. 9. Drive to 10 4] Calculate the pulse width of the signal, and in step 107 turn the switch 106 to l! + $
A pulse signal with a pulse width of 1 is output to the drive circuit 39. After this, the process returns to step 102 again,
Repeat the steps 107 to 107.

While executing the above processing, when the pulse shown at aSb in FIG. Move to interrupt routine.

In the separate routine, in step 108, the value of the free-run timer built into the computer is read (a free-run timer is one whose contents are incremented by 1J at regular intervals), and in the next step 109, the value of the free-run timer built in the computer is read. It is determined whether this interrupt routine is activated by the rising edge of the signal a shown in FIG. The value of the free-run timer is stored in a memory address that can be accessed depending on the case, and after the above processing is completed, the program moves to the main routine and performs normal processing.

FIG. 7 shows in detail the contents of step 101 shown in FIG. 5, and will be explained below along with FIG.

First, in step 201, the engine speed N is set to 11.
N
Wait until it becomes. When N becomes smaller than No, the process proceeds to step 202, where the computer 34 outputs a signal to the drive circuit 39 so that the actuator
00 cam; control to set the 711th oil pressure to "0" in the 111 red chamber 171, i.e. l) Nor retard control,
In the subsequent step 203, the difference t1 in the rising time during full retard control between the signal a from the driven side detector 3 and the signal from the driving side detector 2 shown in FIG. 1(A) is determined. τ in Sfutub 204, 11 of this time difference t1
Determine whether c1 is larger than the preset tmin and smaller than tmax, and if this is ttnin<t +
If <tmax, the process proceeds to step 205; otherwise, the process proceeds to step 208. This r1 capacity range is valid when the detector 2.3 satisfies the conditions for normal installation, or when the shifter 17 is at the full retard position at full retard. This is to prevent an incorrect time difference from being stored as a reference value, for example, when a circuit is incorrectly connected.

In the following steps 205 and 20G, a time lag of a certain set time TV is set. This means that, for example, even if the initial time difference t1 is within the range tmin < t + -tmax, the advance angle θ = 0° may deviate slightly from the cam advance due to an increase in oil viscosity at low temperatures. However, if τ occurs due to poor return of C, by setting a certain running time), the viscosity of the oil ↑ (1 decreases and becomes more /7-Q).
By detecting the value C approaching the cam, fJ (), which represents the relative difference in position, 14 initial phase difference, and 5 initial time X-, the error X can be minimized.

Then, if J3 is in step 207, step 203
Similarly, the difference t2 between 1147 after passing the set time Ty is tl
Then, in step 218, the value of tl is stored in a specific area of the writable memory, and this stored value of 110 is stored as l.
After 'pos', move to the main routine. .

On the other hand, in step 204, the time difference thickness is 1 m.
When it is outside the range of n<t1<tmax, the process moves to step 208, and in step 208, the time difference ^ at an arbitrary point Δ shown in FIG. 8 is calculated.

A time lag of set time 1x is provided in the following steps 209 and 210, and after the set time Tx has elapsed, in step 211, the time difference tB at point B is calculated as if I'y
”. At step 212, the value of t8 is set to the above l m
in J: Determine whether it is larger than tmax and smaller than tmax,
If tanin<tB<jmaX, the process proceeds to step 213; if not, the process returns to step 208 and waits for tmin<[B·, tmax. This is for the reason explained in step 204.

In the following step 213, in step 208 11)
Time 5! ^ From 7th step 211 tl was 1
11, subtract the value of
, l'z -l tmaxl
A time lag of 1 m is provided. This is because by providing a running time as explained in steps 205 and 206, the time difference t gradually decreases even if t l >tmax. Therefore, according to the decreasing change (inclination), how much time has passed since the time difference reached tmax? J:su θ-0
It can be predicted whether a time difference t approaching '/J can be detected.

In the following step 217, the time difference t2 is calculated as in step 207, and the process proceeds to step 218, where the same processing is executed.

Although FIG. 8 shows the case where tl is smaller than tmax, the same applies even if there is a platform C where tl is smaller than t min J:.

Next, FIG. 9 shows in detail the execution content of step 105 in FIG.
Measure the difference t between the pulse of the signal and the pulse of the signal 115,
Next, in step 302, from the value of 11!g ml L measured in step 301,
'1 is the value of Irp03.
il:', L■) Interval f-'I-p. Next, in step 303r, the actual injection timing op is calculated from this value Tp and the engine speed N.

Next, the operation of the fuel injection timing adjustment device described in 1 will be explained.

Now, J-ring rotation speed N1 (rpm), rack υlr
It is assumed that R+r knee operation is the center of operation, and that the injection timing at that time is θ°. Rotation @N from drive side detector 2
A sine wave with a frequency of /j proportional to N1 is input to the waveform shaping circuit 33, and a pulse train (first
The signal is converted to (b) in FIG. 8 and inputted to the Δ terminal of the microcomputer 34.

The output of the driven side detector 3 is passed through the waveform shaping circuit 33 to form a pulse train (Fig. 1 (A) a), which has a frequency equal to that of the rotational speed detector and a time difference according to the injection timing θ0. t pulse train, this is the microcomputer 34
is input to the B terminal of

Then, the microcomputer 34 executes the interrupt routine shown in FIG. 6 by the pulse input to the △ terminal.
Read the value 11 of the free run timer, and since it is an input to the A terminal, write this [i -1' + as Anil of 1)
After storing the data to the address (rotation speed data memory address), the process moves to the main routine. Also, when a pulse is input from the time ll5lt or late t'C[3 terminal, the interrupt routine is activated and reads 11'TT2 of the free run timer, and since the input is from the B terminal, The value Tz of A is stored in memory at 3
After storing to address n (address of injection timing data),
Returning to the main routine, when a pulse is input to the Δ terminal again, the value T3 of the 7 rerun timer at the time of A is stored at address Ay+a.

The processing of the main routine is repeated until the step of the interrupt routine ends and the next interrupt occurs. Step 102: Read data T1 and 3 from rotation speed i data memo 9 address n, △M+, and set N+=+/(1-a
-■+) K+: Deduce the constant and enter the rotation speed data.

Next, in step 103, rack position data R1 is read from the Δ/D conversion circuit 38, and in step 104 F j'-
Map search and 4-point interpolation are performed from data N1 and R1, and [
Singing the l mark 1kY! 'Ilt + - is calculated, and then in step 105, read data T>, T1 from ○ to injection timing data memory address Bn and rotation speed data address J), and t + = -1' + - T2 and then Kono r+l MY -r 1!7are/
:l+f(t + t, the time difference Tll03J:su, 11 "-1+-■pO8" is applied to the injection timing advance amount 0.00 cam 1rted by the above-mentioned Softub 101, and the actual injection timing is determined. Cover with data.

In Sfutub 106.107, compare tl" and tl' 1], △1-=1. "-11' is the wrong time) Old I
Ru. If Δ1−>0, j, Δl in the direction of retardation
” If < O, move in the direction of more advanced angle J11
Made by Nita 1゛! Output jNiI''J to the drive circuit 39 so as to lead IIIJ.

By repeating the above 1-, the adjustment is repeated until the maximum 311 injection timing is reached. For example, the mounting position of the driving side detector 2 or driven side detector 3 may change due to changes over time. Even in such a case, step 101
Memorize the installation +1 position in advance at ℃, then step 10
By performing processing using this value, it is possible to always detect the correct injection timing, and it is possible to adjust the correct injection timing over a long period of time. When assembling the hydraulic actuator 1, be sure to always adjust the injection timing correctly if the detector is installed in the wrong position or if return failure occurs due to increased oil viscosity at low temperatures. That's a monkey.

The above J: Sea urchin The present invention includes: an actuator that determines the relative position of the driven part with respect to the rotating drive member; a driven side detector that outputs a signal synchronized with the rotation of the driven part) 4; When the drive side detector outputs a signal synchronized with the rotation of the drive member and the target injection timing is set, the above is calculated from the time 2r of the signal output from both detectors at 1°. Based on the rotational phase difference between the two members (1), the actual injection timing is detected, the drive signal is corrected according to the difference between the two injection timings, and the actuator is activated.
] - In the fuel injection timing W4 adjustment of an internal combustion engine equipped with a control circuit that suddenly appears (, in the control circuit, the driven member is displaced to a predetermined position at the start of control, and the If the time difference between the signals from the rain detector is within a predetermined range, the time difference obtained after displacement is stored as a reference value, and if it is not within the predetermined range, the time difference is stored as a reference value.
If the time difference falls within the above-mentioned predetermined range; C waits, the time difference determined after the elapse of a predetermined time determined based on the rate of change of the time difference until it falls within the above-mentioned predetermined range is stored as the base Qji value, and is recorded after the star. An internal combustion engine characterized in that the time difference detected by the detector is corrected by the above-mentioned tank, and a means for detecting the actual injection timing is provided based on the phase difference calculated from the corrected time difference. The fuel adjustment system is old.

This has the effect that the actual injection timing of fuel injection can always be accurately detected regardless of variations in the f4 of the detector or changes over time.

In addition, there is no need to precisely adjust the mounting position of the detector as in the past, and the detector can be simply installed in a preset position with a width that is allowable within the correction range. In general, detector collection has the effect of greatly reducing the number of operations required.

[Brief explanation of the drawing]

The drawings show an embodiment of the present invention, and Fig. 1 (a) shows the signal waveform of the detector, and (b) shows the relationship between the advance angle mother and the time difference of 111. Figure 2 is the overall configuration diagram, Figure 3 is the actuator configuration diagram, Figure 4 is the electrical 11i13 box 1 circuit diagram, Figures 5 to 7, and 9 are the micro combination diagrams. Flobe v-1, which shows Cota's actual love program, 8th digit 1 is step 10
It is a graph explaining the result of No. 1. 1...Actuator 2...Drive side detector 3...
- Driven side detector 4... Load detector 5... Electric control circuit 9.10... Pressure control valve 22... Driven member 24
. . . An example of a first-time member is the following components: 1. I-ru cover 33...Waveform shaping circuit 34...Microcomputer 39...Electric drive circuit Agent Patent attorney Established and trained 1 person Figure 1 (A) 4-2-1 (B) Figure 5 Figure 6

Claims (1)

[Scope of Claims] An actuator that determines the relative position of the driven member with respect to the rotating driving member, a driven-side detector that outputs a signal synchronized with the rotation of the driven member, and the driving member Synchronized with the rotation of 1. : A drive-side detector that outputs a signal, and
The actual injection timing is detected based on the rotational phase difference between the two members, which is output from the E2 detector (which is determined from the time difference of g), and the difference between the two injection timings is determined. In the fuel injection timing adjustment system for an internal combustion engine equipped with a control circuit that corrects a drive signal in accordance with and outputs it to the actuator, the control circuit includes a control circuit that causes the driven member to be set at a predetermined 4C1 neck at the time of starting the control. If the time difference of No. 1.1 from the two detectors is within a predetermined range, the time difference obtained after the displacement is stored as a reference value, and if it is not within the predetermined range, the ``-2 predetermined Based on the rate of change of the time difference until it falls within the predetermined range, the time difference obtained after the elapse of the predetermined time is stored as a reference V (and then detected by both of the detectors). A fuel injection timing adjustment device for internal combustion l1llaI, characterized by comprising means for correcting the time difference by the quasi-value and detecting the actual injection timing based on the phase difference derived from the corrected time difference.