JPS603453A - Engine controller - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

[Detailed description of the invention]

The present invention relates to an engine control device, and more particularly to a device capable of controlling the air-fuel ratio of the engine. Generally, the air-fuel ratio of an engine is set so as to obtain the highest thermal efficiency with respect to engine speed and engine load. By the way, if the engine is stopped soon after continuous operation under a high engine load, the cooling capacity for the amount of heat generated by the engine will exceed its limit, and the temperature in the engine room will rise rapidly. Therefore, in the past, cooling performance was ensured by removing only one part that exceeded the allowable temperature and installing a local ring fan, but with these conventional methods, it was necessary to install a separate cooling fan. , a fear that causes a high price,
There is a problem in that an extra space is required for installing the Cooling Link 7. The present invention attempts to solve these problems once and for all, and by controlling the air-fuel ratio, it is possible to reduce the combustion temperature of the combustion engine during high-load operation of the engine. An object of the present invention is to provide an engine control device that can suppress a temperature rise in a room. For this reason, the engine control device of the present invention includes a load detection means for detecting the load state of the engine, and sets the amount of fuel supplied to the combustion chamber of the engine according to the detection result of the load detection means. A fuel supply amount setting means and a fuel supply amount adjustment means for adjusting the amount of fuel supplied to the combustion chamber based on the output of the fuel supply amount setting means are provided.

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When the load detecting means detects a high load state of the engine for a predetermined period of time or more, the fuel supply amount setting means takes priority over the fuel supply amount setting means and the fuel supply amount is larger than the amount set by the fuel supply amount setting means. ! The present invention is characterized in that a control means is provided for controlling the above-mentioned fuel supply amount adjusting means so as to be supplied to the f&burning chamber. Further, the engine control device of the present invention includes a load detection means for detecting the load state of the engine, and a supply amount of fuel to be supplied to the combustion chamber of the engine according to the detection result of the load detection means. 1. Based on the output of the fuel supply amount setting means and the output of the fuel supply amount setting means. ! A fuel supply amount adjusting means for adjusting the amount of fuel supplied to the combustion chamber 1, and a supply air temperature detection means for detecting the temperature of the supply air supplied to the combustion chamber 2 are provided, and the load detection means When a high load state of the engine is detected and the supply air temperature detecting means detects that the temperature of the supply air is equal to or higher than a set value, the fuel supply amount is set in priority over the fuel supply amount setting means. The present invention is characterized in that a control means is provided for controlling the fuel supply amount adjusting means so that more fuel than the supply amount set by the setting means is supplied to the combustion chamber. Hereinafter, an engine control device as an embodiment of the present invention will be explained with reference to the drawings. FIG. 1 is a schematic configuration diagram thereof;
Figure 2 is the main electrical circuit diagram, Figure 3 is a graph to explain its luck 1t zone, Figure 71 is a graph to explain its action, Figure 5 (nL(b) is Fig. 6 is a flowchart for setting the fuel injection pulse width, Fig. 6 is a flowchart for realizing the graph characteristics shown in Fig. 4, and Fig. 7 is a flowchart for driving the fuel injection valve. As shown, a fuel supply amount adjusting means is configured in the air supply passage 1 of the four-cylinder engine E on the upstream side of the part where the throttle valve 3 is disposed and below the part where the air cleaner 5 is disposed. Two electromagnetic fuel injection valves 41
4' is provided. Additionally, a throttle valve 3 open sensor 8 is provided to detect the opening degree of the throttle valve 3.
An idle switch 9 is provided which is closed and turned on when the opening is at the idling opening (fully closed) and is opened (turned off) at other times. Furthermore, the air supply passage 1 in the air cleaner 5 is provided with an air 70-sensor 6 which constitutes a load detection means, and the air supply passage 1 on the downstream side of this air 71:r-sensor is provided with: A supply air temperature sensor (supply air temperature detection means) 7 is provided to detect the temperature of supply air supplied to the engine combustion chamber through the supply air passage 1. In addition, in an engine with a supercharger, this intake air temperature sensor 7 is located above the part where the supercharger is installed. It can be installed either on the O side or on the downstream side. Further, an 02 sensor 10 is provided in the 4J11 air passage 2 of the engine 1 to detect the oxygen concentration in the sushi air. In the pond, there is a water temperature sensor 11 that detects the engine cooling water temperature, and an ignition coil 12 that detects the engine rotation speed from the ignition signal.By the way, these sensors 6- 8 + ] (', 1
= Signals from I2 and switch 9 are from convenience store 1
! ), the computer 13 has an interface 14 . Differential circuit 15.
It is equipped with a frequency dividing circuit 17 and an A/D converter (analog/digital converter) 18, and signals from the air supply source sensor 7, idle switch 9, and water temperature sensor 11 are sent to the A/D converter via the interface 14. The signal from the throttle opening sensor 8 is input to the A7D converter 18 via the differential circuit 15 as a signal having engine acceleration information. Further, the signal from the air 70-sensor 6 is input to the frequency dividing circuit 17. Furthermore, the computer 13 is equipped with a microprocessor (CPLI) 19 as a main control section, and the output from the /D converter 18 is inputted to this microprocessor 19 via a line 20. With,
The air 70-sensor frequency division output from the frequency dividing circuit 17, the output from the O2 sensor 10 (this output is actually supplied via a comparator), and the output from the rotation speed sensor 12 are manually input. The microprocessor sensor 19 sets the amount of fuel supplied to the engine combustion chamber by multiplying the basic data by a correction coefficient based on the information from each sensor to determine the fuel injection pulse width Tout. It has the function of a cooking and cooking JIL setting means, and the engine is in a high load state for a set time T. When it is detected that the supply air temperature AI is less than or equal to the set value Ts, the supply amount set by this fuel supply amount setting means takes priority over the fuel supply amount setting means described in 1. 1) It has the function of a control means for controlling the fuel injection valves 4, 4' so that a large amount of fuel is supplied to the combustion chamber, that is, the air-fuel ratio becomes rich. The microprocessor 19 sends its control output to j) timers 22a and 22b via a pass line 20. 22c. Here, the timer 22a is for one fuel injection valve 4, and turns on and off the solenoid fill 4a of the fuel injection valve 4. Further, the timer 22I) is for the other fuel injection valve 4' and turns on and off the solenoid fill 4'a of the fuel injection valve 4'. The timer 22c is for triggering the control means. By the way, when engine output is plotted on the vertical axis and engine speed is plotted on the horizontal axis, there are various operating modes of this engine as shown in FIG. 3. Then, the microprocessor 19 multiplies the basic data by an appropriate correction coefficient according to these operation modes and outputs desired fuel injection pulse width Tout information to the timer circuit 22. At this time, the fuel supply amount setting means is mainly in charge. Note that the symbol N1clle in FIG. 3 indicates the idle rotation speed of the engine. However, among these 4E modes, there are some high-load zones such as a part of the general driving zone, the high-speed driving zone, and the high-speed full-throttle zone (as you can see from the explanation below, heat damage may occur in this zone. Therefore, if Ennon-E is stopped immediately after continuous operation in the "heat-damaged zone", the engine room temperature will rise abnormally, so some measure is required. For this reason, during operation in the heat-damaged zone as described above, the air-fuel ratio is kept rich. In other words, by making the air-fuel ratio rich, the enon combustion temperature can be suppressed without causing a decrease in output. As a result, the temperature inside the engine room can also be suppressed. Furthermore, even in the heat damage zone described in Section 2, if the supply air temperature At is lower than a certain temperature Ts, heat damage is difficult to stop. Conversely, if the supply air temperature A1 is higher than a certain temperature Ts, the engine temperature will increase significantly. Therefore, the microcomputer 10 is set to operate in the heat damage zone.
The operating condition is such that the supply air temperature At is less than Ts
Hereinafter, when such an operating state is in the heat-suppression-required operation state J, a special correction coefficient is multiplied by the basic data to create a single fuel injection pulse that makes the air-fuel ratio 'Jychi'.
The I″out report is output to the timer circuit 22.The second part is mainly performed by the control means described in (-). The arithmetic processing will be explained using FIG. 5 (,). (IE). FIG. 5 (,) shows the first half of the process, and rtSs diagram (b) shows the second half of the process. The injection pulse width setting 70- is triggered by an interruption of the ignition signal. First, at A1, the supply air amount (intake air amount) A fl l Supply air temperature A
T. Cooling water? M l' u+, engine speed Nr, rate of change in throttle opening (acceleration information) θ, oxygen concentration in exhaust 02 and idle switch on/off/I SeikoμI
s field is loaded. Next, at step A2, it is determined whether the idler switch 9 is on, that is, whether the throttle opening is fully open. If the idle switch 9 is off (throttle opening degree 3 or more open), the basic injection pulse width τb corresponding to Aq (supply air amount) is set at A5. This pulse width τ1
is a signal obtained by appropriately frequency dividing the output of the air 70 - sensor 6 according to the operation mode (this frequency division ratio may be fixed depending on the operation mode, but may also be changed). Intertwining and intertwining from the output signal of the rotation speed sensor 2 are performed. Next, in 86 and A6', the temperature correction coefficient Ktw and the outside temperature correction coefficient Kat are set according to i'u+ (cooling water temperature) and At (supply air temperature), respectively. Then, at A7, it is determined whether d≧S, (S,; positive predetermined value), and if it is in the acceleration state, the Y I E S route is taken, and at 88, the acceleration is set to a value corresponding to the acceleration state. A correction coefficient K11C is set, and if the vehicle is in a non-accelerating state, No. 1 is taken, and Kac is set to 1 by ＼＼. Also, if A is 1.0, it is 1' whether or not it is in j deceleration state.
1], and if i≦−S, (S,; positive predetermined value), it is determined that it is a deceleration state, and the deceleration correction coefficient Kdc is set to a value corresponding to the deceleration state. A11), θ >-8, it is determined that the vehicle is in a non-deceleration state, and Kdc is set to 1. (
A12) Furthermore, the driving zone (specifically ft53
The urban driving zone in the diagram corresponds to this driving zone, and the fifth
In the figure, this linked axis zone is referred to as the fee back area. ) is judged whether ()A13), if feedpa. If it is not in the above range, take the No route and set K4b=1 at A16, and then set the air-fuel ratio according to the engine speed Nr and [Aq (air supply amount)/Nr (engine speed)” at A17. Set the correction coefficient Kaf. Here, A q/N r has a value corresponding to the pressure J in the air supply passage 1, and therefore has an ennon load information. Therefore, in A 1.7, throttle opening information θ, air supply passage pressure information, etc. having the same engine load information 4·IJ can be used instead of Aq/Nr. Further, Kaf is stored in memory in accordance with Nr+Aq/Nr, and is set to a larger value as the load and rotation become higher. After that, as shown in FIG. 5 (1,), at Δ3B, whether Nr≧N52 (NS2 is a predetermined engine rotation speed that can cause heat damage as shown in FIG. 3) is 1! If it is rejected and the condition is not met in A18, take the No route.
In Al1, flag processing is performed to set it to Ml-0, and if the condition in A18 is true, the YES route is set to 9,
In A28, it is determined whether Aq/Nr≧S, (S3; positive predetermined value), and if Aq/Nr<Ss, the No route is taken and the process in A19 (flag process to set M1=0).
will be carried out. After processing A19, A2 (1) checks whether timer 22 (2) has time set or not.
If it is set, the timer 22c is set to T at A23. Nise, after Toshi, M2=+
1 flag place]! l! (A22) is performed. If the timer 22C1 is set to F0, the process of A22 (flag process to set M22()) is performed. After that, flag process to set M3-0 (A23) and M4=0. After the flag processing (A24>), the correction coefficient is set to 2 Kaf at A25. After the processing at A25, the fifth flag is set to A2G so that the fuel injection pulse width Tout satisfies the following equation. Set to: Toul: r bx K twX KaLX Kac
X KdcX K fbX KIn addition, A in Fig. 5(a)
13, if it is determined that the vehicle is in the feed pump area (urban driving zone in Figure 3 1), Kaf=
1 and A14), the correction coefficient Kf corresponding to the oxygen concentration O7
After setting b (Al1), the fuel injection pulse width TouL is calculated in A2G. By the way, if it is determined that Aq/Nr≧83 at A28, take the YES route, and at A20, M1.
= 1 pHIIl'i is done. This I'll disconnection instructs the timer 22c to enter the heat damage zone. Since M 1 = O at first, the No route is taken at A29, the timer 22c is triggered at A30, and the flag processing that M1=1 is performed at A31, and then the process returns to A29 again. As a result, A29 takes the YES route, and A32 checks whether the timer 22c is 0 or not, that is, the set time is 1' after entering the heat damage zone. It is determined whether the period has passed or not. If the timer 22c is not O, the process of Δ22=A213 is performed, but as soon as the timer 22cMO is reached, it is determined in step 33 whether At≧Ts (Ts: positive predetermined value). If the supply air temperature A1 is lower than the set value ゛1゛s,
Take the No route at 33 and process /'1' 22 to A2G, but if At≧1゛s, M at A34.
After processing the flag to set it to 2-1, send Jj to AJ5.
Then, a 1-cut is performed to determine whether I()<≧Kar. If KK<Knf, then J) is in A25 and K""Kaf, and if KK≧Kal', then A36
, let K = KK, and in both cases let this K be A
2 Substitute into 1 of Ci and get fuel injection pulse width 'I”o
A calculation of uL is performed. In other words, if the heat damage zone continues after the set time 'FoJ, the supply air temperature At is equal to or higher than the set value Ts (heat suppression required '1M1lIi:
state), the maximum correction coefficient K is selected. As a result, the value of TouL became extraordinary,
The air-fuel ratio becomes rich. By the way, as shown in FIG.
(> K+niI+),
In order to realize such an increasing characteristic h, a flow as shown in FIG. 6 is prepared in the microprocessor 19. The flow shown in FIG. 6 is triggered by a timer interrupt at every set time.First, in B1, it is checked whether M2=1 or not. If it is in the endothermic suppression operation state, there is no flag processing to set it to M2-1 at A34 in Fig. 5 (1).
/ Therefore, in this case, take YES rule 1 at B], and at B3, it is determined whether 1 (=14 = 1).M4 is initially 0 (BIO processing pot jl!j). Therefore, the No route is taken at B3, and a 1'11 decision is made at B4 as to whether it is M3-1 or not. Since M3 is also initially o (see the process of B6), the No route is taken at B4, and 135 , K K = K
In group, and then in B6, M 3 =
Flag processing to set the value to 3 is performed. In this way, the initial value K In i n is set. Then, since the flag M3-1 was processed at B6, Bl, +33. After passing through B4, processing to set KK=KK0α (α: positive predetermined value) is performed at B7. After that, in B8, whether KK≧+nax is '
1' cutting is performed. 70- by timer interrupt
Each time the is operated, a is added, so the No route is taken at B8 until the predetermined time has elapsed, but after the predetermined time has elapsed, KK≧Kmaχ. As a result, after that, in B9, K K = K max, 131
0, flag processing is performed such that M4=1. Therefore, M 11. After being set to = 1, +
In order to take the YES route in 33, K K =
It is fixed at the state of K + nax. In addition, since the relationship K + oax > Kar > M + nin is added, the set time after entering the heat damage zone is
1'o has elapsed and +3 and the supply air temperature At or Ts or higher (endothermic suppression operation state) is 5. Initially, J+fk fuel injection pulse width T o u with correction coefficient K as Kaf.
The calculation η of t is performed, and after a predetermined time, the correction coefficient K
The fuel injection pulse width ``I''out is calculated using KK as Therefore, take the No route at B1 in Figure 6 and K at B2.
Setting K=0 is performed. That is, KK is reset by the process of B2. In addition, when the idle switch 9 is on, Fig. 5 (,
), it is determined whether Nr≧N51 (NS1; positive predetermined value), and if Nr≧Ns, then proceed to A4) and Tw≧Tuls (1゛llll5; positive predetermined value).
It will be determined whether If the conditions in A3 and A4 are respectively negative, then
In either case, the process of A5 is performed next. Also, if the condition is true for A4, go to A27 in Figure 5 (1)).
The fuel injection pulse width Tout is set to τd (T d; O or a very small %b value). As a result, there is a so-called fuel cut (・ can be brought to a state close to this. By the way, the microprocessor 19 also has a fuel injector drive flow as shown in Figure tjS7.
- is triggered for each Kalman interrupt signal synchronized with the frequency-divided output from the air 70-sensor 6,
At C1, a determination is made whether it is MS-1 or not. If M5=1, the fuel injection pulse width Tout
Set the data in timer 22a (C2), timer 2
After removing 2a (C3), MS=O. (
C4) This causes the electromagnetic fuel injection valve 4 to open for a predetermined period of time. Since MS=O due to the processing in C4, when the next Kalman interrupt signal is input, the No route is taken in C1 and the data of the fuel injection pulse width Tout is sent to the timer 22.
After setting the timer 221 to C5) and triggering the timer 221 (C6), MS-1 is set. (C7) This causes the fuel injection valve 4' to open for a predetermined period of time. In this way, the two fuel injection valves 4, 4 are operated alternately. With the above-mentioned configuration, in the endothermic suppression operation state, due to the action of the control means described in 1, at A26 in FIG. 5 (1+),
Since the larger one of Kaf and KK is substituted into the correction coefficient K, the fuel injection pulse width TouL also becomes large, thereby making it possible to control the dry cooking ratio to be richer than the normal value. As a result, it is possible to suppress the increase in the enon combustion temperature and the temperature in the engine room in the heat absorption suppressed operating state, and even if the engine E is stopped immediately after the heat absorption suppressed operating state, an overheating state will not occur. This makes it possible to omit the conventional twisting fan and the like. Note that there is a difference in supercharger population temperature of about 50 to 101) C between when enrichment is performed and when enrichment is not performed during the above-mentioned endothermic suppression operating state. Further, in operating states other than the heat absorption suppressing operating state, the fuel supply amount setting means performs appropriate air-fuel ratio control according to the operating mode. By the way, in the above embodiment, the set time ``■'' has passed since entering the heat damage zone, and the supply air temperature has not reached the set value T.
s or more, the air-fuel ratio is controlled to the rich side, but even if the set time 'l'' 0 has not elapsed since entering the heat damage zone, the supply air temperature is set even though the temperature is in the heat damage zone. value T
Even in cases where the engine combustion temperature is less than
If the above conditions are satisfied, the air-fuel ratio may be controlled to be rich. In order to realize such control, t
In the IS5 diagram (1)), the YES route of A28 may be connected to the input side of A33. Also, regardless of the high or low supply air temperature, the set time T after entering the heat damage zone. Even if the engine temperature has passed, there is a risk of heat damage as well, so if such conditions are added, the air-fuel ratio may be controlled to the rich side. In order to realize this control, the process of A33 in FIG. 5(1) may be omitted. As detailed above, according to the engine control device of the present invention, when a high engine load state continues for a set time or longer, or when a high engine load state is detected and the intake air temperature is lower than a set value, In this case, the fuel supply amount setting means takes priority over the fuel supply amount setting means and controls the amount of fuel that is larger than the supply amount set by the fuel supply amount setting means to the engine combustion temperature side. This has the advantage that it does not cause a decrease in output even under operating conditions, and can sufficiently suppress an increase in engine combustion temperature. This eliminates the need to install a separate cooling fan as in the past, reducing costs and weight, and also eliminates the need for extra installation space.

[Brief explanation of the drawing]

The figures show an engine control device as an embodiment of the present invention. FIG. 1 is a schematic configuration diagram thereof, FIG. 2 is an electrical circuit diagram of its main parts, and FIG. 3 is a diagram for explaining its operation. Graph, Figure 4 is a graph to explain the effect, Figure 5
Figures (a) and (b) are flowcharts for setting the σ kite injection pulse width, Figure 6 is a flowchart for realizing the graph characteristics in Figure 4, and Figure 7 is a flowchart for setting the fuel injection pulse width. 3 is a flowchart for driving a valve. 1...Air supply passage, 2...Exhaust passage, 3...Thronor valve, 4, 4'...Electromagnetic fuel injection valve, tLa, 4'a, which constitutes fuel supply amount regulation and means. solenoid coil,
5. Air cleaner, 6. Air flow sensor constituting load detection means, 7. Supply air temperature sensor as air supply) quality detection means, 8. Throttle opening sensor, 9. Idle switch, 10. 02 sensor, 11...water temperature sensor, 12...rotation speed sensor, 13...computer serving as fuel supply amount setting means and control means, 14...interface, 15...differentiation circuit, 17...frequency division circuit, 1
8... A/D converter, 19... Microprocessor, 2
0...Pass line, 22...Timer circuit, 22a, 22
'l]122c...Timer, E-engine. Agent Patent Attorney Yoshihiko Iinuma" Figure 3 'JOR' - Figure 4 Haruma wo - Mitsubishi Motors Corporation Passenger Vehicle Technology Center, 1 Nakashinkiri, Hashime-cho, Okazaki City

Claims (2)

[Claims] (1) Load detection means for detecting the load state of the engine;
, fuel supply amount setting means for setting the amount of fuel supplied to the combustion chamber of the combustion chamber in accordance with the detection result of the load detection means; and a fuel supply amount adjusting means for adjusting the fuel supply amount to the fuel supply amount setting means, and when the load detecting means detects a high load state of the Ennon for a predetermined period of time or more, An engine control device comprising: a control means for controlling the fuel supply amount adjusting means so that more fuel than the supply amount set by the fuel supply amount setting means is supplied to the combustion chamber. (2) load detection means for detecting the load state of the engine;
a fuel supply amount setting means for setting the amount of fuel supplied to the combustion chamber of the engine in accordance with the detection result of the load detection means; A fuel supply amount adjustment means for adjusting the amount of fuel supplied to the combustion chamber, and an air supply temperature detection means for detecting the temperature of the air supply supplied to the combustion chamber are provided, and the load detection means detects the engine temperature. When the load condition is detected and the supply air temperature detecting means detects that the temperature of the supply air is equal to or higher than a set value, the fuel supply amount setting means takes priority over the fuel supply amount setting means described in 1. "There is more fuel than the set supply amount."
2. An engine control device characterized in that a control means is provided for controlling the above-mentioned fuel supply adjustment means to be supplied to the combustion chamber.