JPS5943983A - Control method of electric current conduction in glow plug of diesel engine - Google Patents

Abstract

PURPOSE:To control the conduction of an electric current flowing in a glow plug and improve the ignitionability of fuel with its perfect combustion, when the intake pressure of an engine is below a preset value, which shows a critical value causing misfiring of the fuel and is obtained from a speed of the engine, of the intake pressure of the engine. CONSTITUTION:A preset value PK of the intake pressure showing a critical value causing misfiring of fuel is calculated from an engine speed NE, detected by a detection signal from an electromagnetic pick up sensor (not shown in the drawing), and compared with an intake pressure Pm detected by a detection signal from an intake sensor (not shown in the drawing), here in case of the intake pressure Pm smaller than the preset value PK, relays Ry1, Ry2 are operated. Then a glow plug current conduction circuit 48 controls the conduction of an electric current flowing in a glow plug by controlling the relays Ry1, Ry2 to be operated with a driving signal from a driver circuit 68, and temperature of the glow plug is maintained to a range of preset temperature with the improvement of ignitionability of fuel and its perfect combustion.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a glow plug t11 control 7i11 method for a diesel engine. This invention relates to a glow plug energization control method for a Hiko diesel engine that is suitable for use in a diesel engine.

Vehicles such as automobiles equipped with diesel engines are equipped with glow plugs that ignite fuel injected into the combustion chamber of the diesel engine by applying electricity. Conventionally, when controlling the energization of the glow plug, the engine water temperature is detected, the energization time is determined according to the engine water temperature, and the amount of energization to the glow plug is increased during this energization time. Control was performed to maintain the temperature of the plug at a temperature higher than the set temperature required for igniting the fuel. Therefore, when starting the engine, the glow plug raises the temperature of the fuel injected into the combustion chamber to a temperature appropriate for igniting the fuel, making it easier to start the engine.

By the way, when a vehicle travels on a highland or the like where atmospheric pressure is low, the intake pressure of the engine decreases, and the valve loss (work loss in intake and exhaust) increases. However, in this vehicle, the current-carrying side 1iftl of the conventional glow plug is applied.
Because there was no control over the amount of flow of fuel into the glow plug by the engine's intake pressure, there was a problem in that the ignitability of the fuel was extremely low due to a drop in compression pressure.
When such a problem occurs, the unburned slag and gas become white smoke and are discharged from the trachea.1 This white smoke is accompanied by a strange odor, but it also contains harmful gases such as II. (,1
, Co, and N□X, which pollute the atmosphere.

In addition, even if the vehicle is not running on a battery with low atmospheric debris, etc., the noise,
If we perform a control σ1j to reduce the intake air to reduce the image capturing,
The intake pressure of the engine decreases, the ignitability of the fuel tends to decrease, and white smoke is produced.

On the other hand, an engine system has been proposed that corrects the fuel injection timing based on the engine intake pressure in order to prevent white smoke from being generated due to a decrease in the ignitability of the fuel.
If you try to prevent white smoke by correcting the fuel injection timing, the engine will be in a knocking state.
', 1. i, is 4) ivy.

The present invention was made in view of the above-mentioned conventional intelligence 2f11, and its object is to provide a glow plug electric control method for a diesel engine that can improve fuel ignition 41- and completely burn the fuel. Our goal is to provide the following.

In order to achieve the first target, the intake pressure of engine 1 is detected after drilling the main hole, and the set value of the engine intake pressure that indicates the limit value at which fuel misfire occurs is determined based on this engine 1 intake pressure. The present invention is characterized in that when the detected engine intake pressure is equal to or lower than the set value, the current is not traced to the glow plug that ignites the fuel injected into the combustion chamber of the diesel engine.

Hereinafter, preferred embodiments of the present invention will be described based on the drawings.

In No. 11, a configuration diagram of a fuel injection pump and a control device suitable for applying the present invention is shown. Ganarisa;1
There is t-C. The 7% movement control section is controlled by the gear 12 (drive shaft 11 moved by 1μ, this drive sea V) 11 end + The cam plate 14 is fitted loosely into the cam plate 14, and has a spill boat 50 inside.
10, a pump/bubbler/jar 15 that sends the volume to the nozzle 2, a pump 17 that sends the fuel to the nozzle 2 and the timer hist/16,
The timing control valve 19 that determines the advance angle adjustment, the rear solenoid 22, the rear solenoid 22, and the rear solenoid 22, 41. Koirere 23 and ff
1 fl G/G 24 that moves the Subirrig/G 21 to 11, the Spill G/G 21 that is driven by the linear renoid 21 to adjust the injection amount, and the pump plunger 15.
A fuel knot valve (hereinafter referred to as CV) 26 (moving coil 27) controls the supply of fuel to the illumination coil 51.
), a delivery nozzle (consisting of a valve 28), and a delivery nozzle (consisting of a valve 28) and a delivery nozzle (consisting of
It consists of a loop 56 and two regulating valves.

As for the sensor section, the position of the timer piston 16 is determined;
a timer position separator 18 that detects the rotation speed of the gear 12; a rotation speed detector that outputs a pulse signal according to the rotation speed of the gear 12; Spill position 1id
It is composed of 11 sensors 25.

The horn plate 14 rotates and moves back and forth together with the pump plunger 15. This reciprocating motion is caused by the thumb plate 14 riding on the roller 13, which is rotated but is identified with respect to the lTi111 direction of the shaft. The fuel is distributed as the pump plunger 15 rotates 7. The amount of fuel injected is determined by the timing at which the highly compressed fuel 1 is released by the pump plunger 15 at the position of the spill ring 21. Also, excess fuel in the bomb is pumped through the orifice 30 to the pump 13.
In addition, the linear solenoid 22 in the fuel pump 1 and the i'c V26 are controlled by the control device 3, but for this purpose the output signals of the sensors of each A and (e) are taken in. .That is, the city: (1saki pitsukuapuse/
Machining by the 20 /] / rotation speed multiple SN and spill position 1
Output signal S of me/za 25 Each signal of s is it+l+
The data is taken into the control device 3.

In addition, Ill'1ili1moii+j 3 includes the detection of the intake air temperature sensor No. 10 S h, which is also provided on the intake manifold 4, and the detection of the intake pressure sensor No. 6 also provided on the intake manifold 4. Signal Sp, detection signal SW of water temperature sensor 11 that detects engine cooling water humidity, accelerator 80
Child of accelerator sensor 9 that detects flI+incorporated acid! Output No. 13 5acc, ignition switch 400 on, ignition signal 1g which is No. 16 according to the condition 1 horse, starter switch St which is the mercy according to the on and off condition j ha 1 of the starter switch 42, respectively ( ,
It; It's confusing. Control 11 device ff3 is for each German Sen'+
Detection 4M etc. from I'r+p as j:l'y,
Based on these No. 4a, the driving of the fuel injection hob l and the tether engine 10 can be controlled by ψ1j.

Further, the I/Dike manifold 44 of the Tessel Enno/10 is provided with a glow plug 46 that ignites the fuel injected into the combustion chamber of the diesel engine 10 by energizing it8. The circuit 48 generates a power supply, and the injected fuel can be heated according to the amount of current supplied.
The lill side 1 is performed according to a command from the control device 3.

FIG. 2 shows a diagram at 41 in the case where the opening side 1 device 1G of FIG. 1 is configured with a microcomputer.

Control device l+' shown in FIG. 2; 3 is the CPU 61
R08462, which stores the processing programs and monitor programs for executing each process, with R08462 as the core.
, the deductive content and the output content of each machine sensor are temporarily stored. j i(;＋(),
IlA IVI 63, which has a backup memory that continues to store settings, input and output values, etc. 4.65
, A/D exchanger 66, multiplexer 67, drive circuit 68, 69, 70, etc.
Toro 4.65, CPU 61, I included OM 62, lj A
fvI 63 is connected by a husband h path line 71. , and each detection signal of the water temperature sensor 7, intake temperature sensor 5, intake pressure sensor 6, and accelerator sensor 9 is sent to a buffer circuit 7.
2.73.74.75 is supplied to the multiplexer 67 via the spill position sensor 25, the timer position 11/the 18L/) each detection width is set/'I No. 1 detection circuit 76.77 is supplied to multiplexer 67 via. -(-/The output supplied to multiplexer 67 is A
/ IJ i4 external device 66 converts it into a digital signal and supplies it to the input/output capotro 4 as a take. Further, the starter signal St and the ignition signal Ig are supplied to the input/output capotro 5 via buffer circuits 78 and 79, respectively.

Further, the detection signal of the %41!4 bit amplifier/zer 20 is supplied to C)'U61 via a waveform shaping circuit 80. .

Further, a signal from the sensing resistor 1 provided in the energizing circuit of the glow plug 46 to detect the energizing needle supplied to the glow plug 4o is supplied to the multiplexer 67 via the heavy pressure detection circuit 82.

The CPU 61 performs various calculations based on the signals from the various sensors, etc., and outputs drive signals for driving the energizing needle of the glow plug 46, the fuel pump, etc. That is, when controlling the amount of electricity supplied to the glow plug 46, the drive circuit 6
When controlling the drive HiJ+ of the FCV 26, the drive signal is supplied to the drive circuit 69. In addition, when driving the linear solenoid 22, the D/A converter 8
4. Supplying a drive signal to the drive circuit 70 via the servo/pump 86; 1; CPU 61;
65, an A/D converter 66, and a clock circuit 90 for sending clock pulses to the D/A converter 84. .

FIG. 3 shows a configuration diagram for clarifying the specific configuration of the glow plug energizing circuit 48.

The glow plug energizing circuit 48 is composed of a sensing register 1, a glow plug register R6, a relay 100, and a relay 102.
is the equivalent resistance of glow plug 46 17 2.1 7 5.1 core 4
, R5. 1. ', M j ,
Excitation of 1 and y2 (1G coil L1, L2 each controlled box manufacturing 3
The sensing resistor 1<, 10 is connected to the voltage detection circuit 82 at both ends, and the equivalent resistance 11 is also connected to the voltage detection circuit 82. , 1ri 3.1 (4,
1, (5 is 11); As the quantity increases, its resistance value increases by 1.1, and the resistance value of glow plug resistor R6 is 0.LQ, sensing resistor 1. The resistance value of 1 is 10mm, the equivalent resistance) is also 2~15
The resistance value is 0.6 to 0.8-Q.

The glow plaque communication circuit 48 in this embodiment configured as described above is composed of;
Claw plug 46 is activated by controlling relay Ry+, L y 2's I middle 11 with Xlt:I using the mB mountain A word.
Turn on electricity, control the meter, and set the temperature of glow plaque 46 to 1 (V).
can be created around the setting 1liA surface). , Shi1
1, 1, When the relays It y 1 and y y 2 are operated by the drive number 1 g from the U movement circuit 68, only the sensing register it + is contained in the Jj-m circuit of the claw lug 48, The current required to rapidly heat the glow plaque 46 is supplied to the thermal resistance 1? , 2~II (5) As a result, when the temperature IU of the glow plug 4G increases rapidly, the resistance value of the star resistance [7, 2~I?, 5 increases, and as a result, the resistance value of the glow plug 4G increases. >ut Tlj >'A decreases, so the voltage drop across the sensing resistor 1 and 1 decreases.

The temperature of the glow plug 46 is set to J, for example 7.
Judgment as to whether or not it is within 50°O to 900'U is determined by sensing register J ('14.1' applied to 1, pressure and se/single/star) core 1 car X city, pressure drop. Towo゛Pli
This can be done by detecting with the pressure detection circuit 82.

That is, in this embodiment, 21: when relay Ry10 is activated and when it is not activated 1)! In I, the voltage applied to the sensing resistor R1 is different, but when the temperature of the glow plug 46 changes over the set temperature range, the equivalent resistance is 1 to 2 to 5.
The voltage drop is set in advance in association with the voltage applied to the sensing register R1 when the relay Ryl is activated and when it is not activated, and the voltage drop across the sensing register R1 for each applied voltage. ;,-(By this, it is possible to determine whether the temperature of the glow plug 46 is within the set temperature range.

For spear, 111. Pressure detection times h! f? 82 sets the temperature of the glow plug 46 to 1liA degrees (9(lo″o
) is detected and relay 1jyl is deactivated, 460 glow plugs are connected; the circuit includes glow plug resistors I<, 6, and the equivalent resistance fj 2
Since the amount of current applied to the cables 1 and 5 is reduced, the temperature of the rope block 46 can be lowered. Also, the crime of relay 1ζy1 +
1iIl lowers the glow plug 46 by 17+i degrees and increases the pressure drop across both ends of the sensing resistor 1. Even if the voltage drop at both ends of the sensing resistor 1 increases, the voltage applied to the sensing resistor 1 at this time and the sensing resistor 1% S ii' By detecting the pressure drop at the +i end, it is possible to detect when the temperature of the glow plug 46 has fallen below the set temperature +1i (750°C). Glow plug 46 by operating Ryj
By increasing the amount of current applied to the glow plug 46, the temperature IQ of the glow plug 46 can be increased. 1 In this way, by repeating the operation of the relay (yl), the temperature of the glow plug 46 can be maintained at the preset temperature qlF>.

By the way, in Diesel E/J/ (cl:, 4th
As shown in the figure, engine rotation speed (r l) IT
A region in which white I smoke is generated occurs in relation to the engine intake pressure Cmm1-1g a b s (absolute pressure)]. Therefore, in the actual Mli example,
As shown in FIG. 5, the engine intake pressure set value Pki is stored in the ROM 62 in association with the engine intake pressure (rpm) as the limit value at which fuel misfire occurs.
, the engine/engine rotational speed and the intake pressure of the engine are detected to determine whether or not the engine is in region 1 where white smoke is generated.

Next, the operation according to the present invention will be explained based on the flow chart shown in FIG.

1. At step 100, the electromagnetic big 7" (
= Engine rotation speed NE based on the detection signal from Nya 20
, the intake pressure P 1 is determined by the detection signal from the intake pressure sensor 6.
11, the temperature 'Fo of the clove lug 46 is detected by the detection signal from the voltage detection circuit 82, and the process moves to the strobe lug 101. In step 101, e/gin times 〒UK 7
・+ε degree N F, the limit where fuel misfire occurs (ji'
Step 1: Calculate the set value p k of the air pressure that indicates i.
In step 102, it is determined whether or not the released intake pressure Pm is smaller than the set value Pk of the intake pressure.In step 1021+C, the intake pressure pm is equal to the set value j. ]1 (If it is smaller than step 103, the relays -14Y1 and ly2 are operated. Next, the process moves to step 104 and determines whether the temperature TO of the glow plug 46 is lower than the set temperature 1y, for example 90000. 3. In step 104, the temperature JQI 'I' of the claw flag 40 (if 1 is lower than the set temperature, the process moves to step 105, and the II phantom circuit 68
1 drive signal from relay Ity1! L mountain r
Successively complete it. At this time, relay 1 and relay 12 are also activated, so that the communication to glow plug 46 is reduced.
+if(l increases and the temperature of the claw plug 46 rises by 2.

If the determination in step 104 is NO, the process moves to step 106, where the drive signal from the drive circuit 68 is stopped and the excitation coils I and I become de-energized. 1. Is there less current than when the coil LI is in the energized iH state? was introduced, and the glow plug 46's level gradually decreased by one generation.

On the other hand, if it is determined that JO and i'1) are determined in step 102, the process moves to step 107.
For y1 and ky2. 1 signal is not output, and relays RY i and Ry 2 are both inactive. .

In this way, in this example 1'ct=Example 1, when the intake pressure is below the set pressure, 1111 electricity is applied to the glow plug, and when the temperature of the glow plug is below the set temperature &J, the glow plug suddenly increases. Since the temperature of the claw flag is raised to within the set temperature by the automatic control, even if the intake pressure falls below the set pressure, it is possible to prevent the fuel from misfiring.

Furthermore, if the method for controlling the current flow of the globe lattice in this embodiment is applied to a vehicle equipped with an engine equipped with an intake throttling system, even if the intake throttling is increased by 1illφl, it will be possible to prevent the fuel from misfiring. It can be prevented.

Also, what about this example? By applying the glow plug energization control method 1, it is possible to prevent the generation of white smoke due to fuel misfire without having to perform control to correct the injection timing based on the intake pressure.

Furthermore, according to this embodiment, misfires of fuel can be prevented, so
Since the fuel can be completely combusted, it is possible to improve torque and also to improve combustion N.

Furthermore, in the above embodiment, it was discussed that the flow to the glow plug was carried out by detecting the engine rotational speed and the engine intake pressure, but only the engine intake pressure was detected and the fuel flow was detected. A set value of intake pressure indicating a limit value at which a misfire occurs is determined in advance, this set value is compared with the detected intake pressure, and the glow plug is energized when the intake pressure of the engine is below the set value. 3, the same effect as the above embodiment can be obtained even if
The engine rotation speed and the fuel injection amount (accelerator opening) are used to predetermine the load range in which the fuel will misfire.
Even if the engine rotation speed IW and the fuel injection amount are detected and the engine/ is in the set load range based on these detection signals, the same effect as in the above embodiment can be obtained by performing 1) j:. can get.

Further, in the above embodiment, when the engine water temperature is cold, the set value of the engine intake pressure is set to, for example, 720 m
If the value is increased from mi(gabs) to 800 mm l-1 gabS, even better opening side 1 can be achieved.

As explained above, according to the present invention, even if the intake pressure of the engine falls below the intake pressure set value that indicates the limit value at which fuel misfire occurs, the engine 4 and 1 will be in a misfire state. It has an excellent effect of preventing white smoke from occurring.

[Brief explanation of drawings]

FIG. 1 is a block diagram of a reservoir made up of a fuel injection pump and an open-side j device to which the present invention is applied, FIG. The figure is a configuration diagram to explain the configuration of the globe lag 1]1 harm 1 circuit shown in Figure 1. Figure 4 is a diagram to explain the white smoke generation area caused by the relationship between engine speed and engine intake pressure. FIG. 5 is a diagram showing the relationship between engine intake pressure and engine rotational speed, and FIG. 6 is a flowchart for explaining the operation of the present invention. ■...Fuel injection pump 2...I/Siection nozzle 3...Control (i+:1 device 6...Intake pressure sensor 7...Water temperature sensor 20...'Electric value pickup sensor 40... Ignition switch 42... Starter switch 46... Claw plug 48 - Glow plug connection 1st division agent Tatsuyuki Unuma (tit, or 2 people) Fig. 4 mmHgabs mmHg @51 mmHgabs engineering engine Encyclical Yumune Oni (xlo3rpm) Figure 6

Claims (2)

[Claims] (1): Detect the engine intake pressure of the engine, compare this engine intake pressure with a set value of engine intake pressure that indicates the limit value at which fuel misfire occurs, and check if the detected engine intake pressure is less than the set value. A method for controlling a glow plug passage 11'L of a diesel engine, characterized in that, at the time of , energization is applied to a glow plug that ignites fuel injected into a combustion chamber of a diesel engine. (2) A glow plug for a diesel engine; a 1-ft electric control method according to claim 1, in which the set value of the intake pressure is determined from the engine/engine rotational speed.