JPS59136540A - Method of correcting desired idling speed - Google Patents

Abstract

PURPOSE:To enable to correct the desired idling speed with ease, by correcting the desired idling speed on the basis of the number of times when an accelerator pedal is depressed in stopping an internal combustion engine having an idling- speed control apparatus for controlling the flow rate of air by-passing a throttle valve. CONSTITUTION:An idling-speed controlling apparatus shown in the drawing has an idling-speed control valve 13 disposed in a by-pass passage 12 by-passing a throttle valve 10, and the valve 13 is controlled by an electronic control circuit 20 on the basis of the outputs of an oxygen sensor 5, a sensor 8 for detecting the temperature of intake air, a water-temperature sensor 9 and an air-flow meter 14. When a T-terminal is short-circuited at the time of stopping an engine, ON-OFF switching of an idle switch 26 is repeated through operation of the accelerator pedal, and the count of a prescribed counter is increased by the number of times of ON-OFF switching caused by the switch 26. Subsequently, when the engine is started and set into idling operation, the desired idling speed is corrected on the basis of the corrected count value.

Description

[Detailed Description of the Invention] Industrial Application Field] The present invention is an idle speed control system (hereinafter referred to as LSC).
The present invention provides a method for correcting the target engine speed at idle, which is preset in the rSC of an internal combustion engine.

Prior Art In an internal combustion engine having an ISO that performs feedback control of the idle speed, the idle speed is set ε1 so that the speed is automatically controlled to a speed corresponding to various situations. However, these target rotational speeds are
Although this value is common to many internal combustion engines of the same type, there are individual differences among individual internal combustion engines, so there is a slight deviation from the optimum value. For this reason, if the target rotation speed is too high than the optimum value, the internal combustion engine rotation will increase more than necessary during idling, resulting in poor fuel efficiency.
On the other hand, if the target rotation speed is too low, the engine rotation will become unstable,
If other loads were added at such times, there was a risk that the engine would stall. This adjustment of the target rotation speed for each internal combustion engine could not be carried out in the automobile assembly process because individual differences between engines have not yet been determined. Therefore, it is necessary to have a target rotation speed adjustment device that can be adjusted after assembly, for example at a maintenance shop, but providing such a special device itself requires extra materials, increases cost and weight, and also There are significant disadvantages such as the need to secure a mounting location and an increase in maintenance and inspection work, so no practical product has yet been realized.

[Object of the Invention] In view of the above-mentioned problems, the inventors of the present invention have conducted intensive studies to find a way to easily adjust the target idle speed to the optimum value without installing any special equipment, even after the automobile is assembled. It is a completed invention.

[174 features of the invention] That is, the gist of the present invention is to provide an idle speed control valve which is provided with an idle speed control valve and which adjusts the amount of air passed through the idle speed control valve during starting and idling of an internal combustion engine. When an internal combustion engine having a rotation speed control device is stopped, an idle target rotation speed correction claw is calculated based on the number of times the accelerator pedal is depressed, and the idle target rotation speed is set during feedback control based on the correction at. This is the method for correcting the target idle rotation speed. The present invention will be described below with reference to the drawings.

[Embodiment] FIG. 1 shows a configuration example of an internal combustion engine control system including an idle speed control device to which the present invention is applied.

In the figure, 1 is the engine body, 2 is the piston,
3 is a spark plug; 4 is an exhaust manifold; 5 is an oxygen sensor provided in the exhaust manifold 4 and detects the residual oxygen concentration in the exhaust gas; 6 is a fuel injection valve that injects fuel into the intake air of the engine body 1; 7 is an intake manifold; 8 is an intake temperature sensor 9- which is provided in the intake manifold 7 and detects the temperature of the intake air sent to the engine body 1; 9 is a water temperature sensor that detects the temperature of engine cooling water; 10 is a throttle valve. , 12 is a bypass passage that bypasses the throttle valve 10, 13 is an idle speed control valve (ISCV) that controls the opening area of the bypass passage 12, and 14 is an air flow valve that measures the amount of intake air.
Meters 15 each represent an air cleaner that purifies the intake air. In addition, the above throttle valve 10
A thrower 1 position sensor (not shown) that outputs a signal corresponding to the opening degree of the thrower 1 to valve 10 to the electronic control circuit 20 is also installed.

In addition, 16 is an electric valve that outputs the high voltage necessary for ignition, 1
7 is a distributor that is linked to a crankshaft (not shown) and distributes and supplies the high voltage generated by the above-mentioned igniter 16 to the spark plugs 3 of each cylinder; 18 is installed inside the distributor 17, and connects the
19 is the distributor 1
7, a cylinder discrimination sensor which outputs one pulse signal per revolution; 20, an electronic control circuit; 21, a key switch; and 22, a starter motor.

When idling, the electronic control circuit 20 operates based on data from the hinges 5, 8, 9 and the air flow meter 14.
The ISO is configured to control the SCV 13 and the air flow rate of the bypass passage 12.

Further, 23 indicates a passage through which air flows bypassing the throttle valve when the engine is cold, that is, a fast idle bypass passage. 24 indicates an air valve that controls the amount of air passing through the fast idle bypass passage 23. Note that the air valve 24 is set to I when the engine is cold.
7 to ensure the engine speed required for IJ machine operation
It operates so as to listen to the ground 1 to idle bypass path 23.

Reference numeral 25 indicates a T terminal. This T terminal 25 is an initial set terminal for idle adjustment, and by short-circuiting this by, for example, grounding, the idle target rotation speed and ignition timing of the internal combustion engine set in the electronic control circuit 20 can be adjusted. etc., to return them to their basic state. This means that when the T terminal 25 is short-circuited, the basic value of the idle rotation speed, for example, the target rotation speed before correction, can be set or changed.

Reference numeral 26 indicates an idle switch, which is linked to the accelerator pedal and is on when the accelerator pedal is not depressed. Reference numeral 27 indicates a full open switch, which is turned on when the throttle valve 10 is generally close to full open, at 55 to 600 or more.

FIG. 2 shows a 7079 diagram of the electronic control circuit 20.

30 is a central processing unit (hereinafter simply referred to as CP LJ) that inputs and calculates data output from each sensor according to a control program, and performs processing for controlling the operation of various devices such as 15CV13;
31 is a read-only memory (hereinafter simply referred to as ROM) in which the control program and initial data are stored; 32;
is a random access memory (in which data input to the electronic control circuit 20 and data necessary for arithmetic control are read and written).
Reference numeral 33 denotes a backup random access memory (hereinafter simply referred to as a backup RAM), which is backed up by a random access memory so as to retain data necessary for engine operation even when the key switch 21 is turned off; Input ports (not shown), waveform shaping circuits provided as necessary, output signals of each sensor
Each shows an input section equipped with a multiplexer that selectively outputs to the PU 30 and an A/D converter cap that converts an analog signal into a digital signal. Reference numeral 35 is an input/output unit equipped with a drive circuit, etc. that drives the CPU 30 to control the CPU 30 (input/output section, etc. that drives according to number i).
36 is each element such as CPU 30, ROM 31, etc.
The path lines connecting the section 34 and the input/output section 35 and through which each data is sent are respectively shown.

A first example using the above-mentioned 1=equipment will be shown next.

FIG. 3 shows a flowchart of the process.1 This embodiment is represented by subroutine A, one of the various processes of the electronic control circuit 20.

Next, the processing of this embodiment will be specifically explained according to Subroutine A.

First, the key switch 21 is turned on to start the process, but if the T terminal is not short-circuited, rNOJ is determined at step 41, and the tree subroutine A ends without any other processing.

Next, if the T terminal is short-circuited and the internal combustion engine is rotating, rYESJ is determined in step 41, but rNOJ is determined in step 42, and this subroutine A is exited. It ends without any processing being done.

Next, if the T terminal is short-circuited and the internal combustion engine has stopped, it is determined in steps 41 and 42 that rYEsJ, and then in step 43 it is determined whether the idle switch (LL) is on. If the accelerator pedal is not pressed at this point, it is Aisle Switchmen, so I' Y E
If it is determined as SJ, then in step 44 the flag is reset or if it has already been reset, the reset state is maintained and the tree subroutine A is skipped. If the accelerator pedal is not operated while the key switch 21 is turned on, step 4 will be performed in the same way in this subroutine 8.
The process through 1.42.43:44 is repeated.

Next, when the idle switch is turned off by operating the accelerator pedal, it is determined in step 43 that it is rNOJ, and then in step 45 it is determined whether the throttle valve full open switch (, V L ) is turned on. It will be judged. If the depressed state is between the idle switch on and the fully open switch on, the fully open switch is A.
Therefore, in step 45, it is determined to be rNOJ.

Next, in step 46, it is determined whether the flag is set. Step 4 to the previous tree routine
Since the flag attribute is in the reset state in step 4, the determination in step 46 is "NO", and then in step 47 the counter NFO is incremented. Since the initial setting of NFO is O, NFO is set in the first step 47.
FO=1. Step 48 is then processed and a flag is set. In this way, the present subroutine A is exited.

Next, when the process returns to this subroutine A, when the idle switch is off and the full throttle switch is off in the same state,
After steps 41.42.43.45, step 46
Since the flag was set in step 48 of the previous subroutine A, the determination is rYEsJ and the process directly exits from the subroutine Δ. After this,
As long as the idle switch is off and the full open switch is off, in this rib routine A, steps 41 and 42 are performed.
．． The process going through steps 43, 45, and 46 will be repeated.

During this time, NFO is not incremented to 1, and NFO is not incremented to 1.
FO=1 remains.

Next, when the accelerator pedal is released from the above state, the idle switch is turned on again. At this time, the process of subroutine A is determined to be r' Y E S J at step 43, and then, at step 44, the flag is reset.

As long as the idle switch is on, step 41
．． Processing continues through 42.43.44.

Next, when the accelerator pedal is depressed again, step 47 is processed again and N F Olfi 1 It
is incremented by

In other words, by operating the accelerator pedal, the idle switch is set to A.
As the idle switch is turned on and off repeatedly, the NFO increases by the number of times the idle switch is turned off.

In this way, NFO can be determined by the number of times the accelerator pedal is depressed. Therefore, after this, when the internal combustion engine is started and becomes the idle state 1, the desired NF is determined by correcting NF based on NFO in subroutine B for determining the target rotation speed NF shown in Fig. 4. This makes it possible to select the target rotation speed most suitable for the engine. Subroutine B is a part of the ISO feedback control, in which step 51 represents a process of calculating the target rotation speed NF according to the load condition of the internal combustion engine, and step 52 represents the process of calculating the target rotation speed NF in accordance with the load condition of the internal combustion engine. is determined in subroutine A and is corrected based on I/N1:O. For example, the correction of N'' can be done using the following formula (1
).

NF+ (NFOXlo)r, p, m, -- (1) In other words, the target rotational speed increases by 10 rpm for each value of NFO.

Returning to Figure 3 again, if you then press the accelerator pedal deeply until the full open switch is turned on, the process will proceed to step 4.
After 1.42.43, it is determined in step 45 that it is rYEsJ. Processing then moves to step 49 where N
FO is cleared, the [flag is set in the next step 5, and this subroutine A is exited. After this step 41.42.43.45 as long as full open switch on
．． 49.50 is processed and the NFO remains cleared. Next, when the accelerator pedal is gradually returned and the full-open switch is turned off, steps 41, 42, 43, and 45 are passed, and in step 46, step 5 when the full-open switch is turned on is executed.
Since the flag remains let in the processing with 0, r
The determination is YESJ, and this subroutine A is exited with the NFO unchanged and cleared. The same process continues after this N
FO is kept clear. If the accelerator pedal is then fully released and the idle switch is turned on, the process will go through steps 41.42.43.44.

From the above, the switch to fully open the accelerator pedal is AJ.
If you go deep enough to clear the NFO, you can return to the initial basic state.
Re-r! I can set it up and do it.

After performing the above-mentioned series of operations and setting jNFo, if the short-circuit condition of the ■terminal is resolved, the subroutine A only makes the determination in step 41.
There is no change to the NFO, and the set NFO value can be maintained as is.

Furthermore, by storing the value of NFO in the backup RAM 33, the engine can be operated in an appropriate idling state without repeating the same operation when starting the engine.

Next, FIG. 5 shows a flowchart of the second embodiment. Similar to the first embodiment, this embodiment is represented by subroutine C, which is one of the various processes of the electronic control circuit 20.

This subroutine C is a modification of the subroutine of the first embodiment with a correction processing function that can set the counter NFO to a negative value and reduce the target idle rotation speed from the value set at the time of assembly. .

Next, the processing of this embodiment will be specifically explained according to subroutine C.

The process is started by turning on the "Ma-zu" key switch 21, but if the T terminal is not short-circuited, rNOJ is determined in step 61, and then step 78
At this point, flag [22 is reset, and this subroutine C ends without any other processing.

Next, if the T terminal is short-circuited and the internal combustion engine is rotating, rYEsJ is determined in step 61, but rNOJ is determined in step 62, and this subroutine C is exited. The process ends without any other processing being performed.

Next, if the T terminal is short-circuited and the internal combustion engine is stopped, it is determined in steps 61 and 62 that rYEsJ, and then in step 63 it is determined whether or not the idle switch is on. If the accelerator pedal is not pressed at this point, the idle switch is on, so rYEsJ
or if it has already been reset, the reset state is maintained, and in step 65 the 7 lag
3 resets routine C] or the reset state is held. If the accelerator pedal is not operated while the key switch 21 is turned on, the steps 61, 62, and 63 in this subroutine C will be repeated.
．． The process through steps 64 and 65 is repeated.

Next, when the idle switch is turned off due to the accelerator pedal operation, it is determined in step 63 that it is rNOJ, and then in step 66 it is determined whether or not the throttle valve full open switch (VL) is turned on. Ru.

If the depressed state is between the idle switch on and the fully open switch on, the fully open switch is off, and therefore rNOJ is determined in step 66''.

Next, in step 67, it is determined whether the flag F1 is set. Since Fl is in the reset state in the process of step 64 of the immediately preceding subroutine C, the determination in step 67 is I'NOJ. Then step 68
It is determined whether the flag F3 is set to 1 or less. Since F2 is in the reset state in the process of step 78, it is determined that it is rNOj in step 68, and step 6
At step 9, the counter NFO is incremented by one. N.F.
Since the initial setting of O is O, NFO=1 in the first step 69 processing. Step 71 is then processed and Fl is hit. In this way, the main routine C is exited.

Next, when the process returns to this subroutine C, when the idle switch is off and the full throttle switch is off in the same state,
Step 67 via steps 61, 62, 63, 66
In this case, in step 71 of the previous subroutine C,
Since l has been set, the determination is rYEsJ here, and after F3 is reset or held at let in step 65, this subroutine C is exited. After this, as long as the idle switch is off and the fully open switch is off, in this subroutine C, steps 61.62.6
The process of exiting from this subroutine C via 3.66.67.65 is repeated 1. During this time, NFO is not incremented to 1 and remains at N'O-1.

Next, when the accelerator pedal is released from the above state, the idle switch is turned on again. At this time, the processing of subroutine C is determined to be rYEsJ at step 63, then at step 64, [1 is reset to 1-, and at step 65, ``3 is held as a reset.As long as the idle switch is turned on, 61.62.63.64.6
The process continues through step 5 and exits from subroutine C.

Next, when the accelerator pedal is depressed again, the process reaches step 68, but since F2 remains reset, step 68 is determined to be rNOJ, step 69 is processed again, and NFO is incremented once. be done.

That is, in this state, as in the first embodiment, by repeatedly turning the idle switch on and off by operating the accelerator pedal, the NFO can be increased by the number of times the idle switch is turned off. By correcting the NF based on the NFO in subroutine B mentioned above, it is possible to determine the desired NF in the same way as in the first embodiment, and it is possible to select the optimum target rotation speed for the engine. can.

Next, when the accelerator pedal is depressed deeply until the full-open switch is turned on, the process passes through steps 61, 62, and 63, and is determined to be TrYEsJ in step 66. Processing then moves to step 72 where the NFO is cleared. Next, in step 73, it is determined whether the flag F3 is set or not. Also, since the flag F3 remains in the reset state, it is determined that it is r NO OJ, and then in step 74 it is determined whether or not F2 is turned on. Since F2 is still in the reset state, rNOJ is determined in step 74, then F2 is set in step 75, F3 is also set in step 77, and the subroutine C is exited.

Next, if the process enters this subroutine C again with all the questions still switched on, the process goes to step 61.62.6.
Step 73 is reached through 3.66.72. Since F3 is in the Ceramyl state in the process of step 77 of the immediately preceding subroutine C, it is determined in step 73 that it is rYEsJ. Next, in step 71, Fl is held in the set state and the present subroutine C is exited. After this, as long as the fully open switch-on state continues, this subroutine C
In step 61.62.63.66.72.73.
71 is repeated. All in all, F2 is kept in the set state and NFO is kept in the cleared state.

Next, when the accelerator pedal is gradually released and the full open switch is turned off, steps 61, 62, 63, and 66 are performed, and then in step 67, Fl is hit in the process of step 71 when the full open switch is turned on. There are up to
It is determined that rYEsJ, and after resetting F3 in step 65 with NFO unchanged and clear, the process exits from this subroutine C. If the same accelerator pedal condition continues, the same process will continue and the NFO will remain clear.

If the accelerator pedal is then fully released and the idle switch is turned on, the process proceeds to step 61.62.6.
It will pass through 3.64.65.

As a result, ``1'' is reset to 1~.Then, when the accelerator pedal is depressed again and the idle switch is turned off, the process proceeds to step 61.62.63.6.
6, the process reaches step 67. In this step 67, since Fl is in the reset state, it is determined to be rNOJ, and the process moves to step 68, where it is determined whether or not F2 is set. This [2 remains in the state of F2 set when the full open switch was turned on last, and since F2 was set in step 75, it is determined to be rYEsJ. As a result, in step 70, NFO is decremented. Since NFO was also cleared to 1 in the process of the last step 72, its value becomes -1 as a result of being decremented. Next, the process sets 1:1 in step 71 and exits from this subroutine C, but if the accelerator pedal is in the same state next time, the process goes to steps 61, 62, 63.
66, step 67 is reached, and since "1" is in the set state, it is determined to be rYEsJ. Next, in step 65, F3 is reset, and this subroutine C is exited.

In other words, the value of NFO does not change and remains -1.

Furthermore, if you release the accelerator pedal and turn on the idle switch, step 6-4 will be executed and Fl will be reset. If you press the accelerator pedal again, step 70 will be executed only once, and N"O will be decremented. be done.

In other words, the idle switch can be turned on/off using the accelerator pedal.
If you repeat the off, the NF will be as many as the number of times it was turned off.
O is decremented and NFO can be set to any negative value required.

Also, if it becomes necessary to set a positive value to NFO again, press the accelerator pedal until the full open switch is turned on, the NFO will be cleared in step 72, and ``YES'' will be set in step 74. ", and then in step 76, F2 is relet. If the accelerator pedal is then released and the idle switch is turned on and off repeatedly, NFO is incremented from 1 to positive by the number of times the idle switch is turned off. The value can be set to NFO.

Simply turn on the key switch and start the internal combustion engine.
With the T terminal short-circuited -U, the counter NFO can be increased by the number of times the idle switch is turned on/off as needed by lightly operating the accelerator pedal. Therefore, the idle target rotation speed that is modified based on the NFO can be set to a higher desired rotation speed. Furthermore, if the driver depresses the accelerator pedal deeply and turns on the full-open switch once, then the idle switch can be repeatedly turned on and off by lightly pressing the accelerator pedal, thereby decreasing the counter NFO by that number. Therefore, the idle target rotation speed can be set to a lower desired rotation speed. If the full open switch is turned on a second time, the NFO processing can be returned to the increment processing again. In other words, if the fully open switch is not turned on or is turned on an even number of times, the NFO will be incremented, and if it is turned on an odd number of times, it will be decremented, which can be freely selected.

In the second embodiment, by carrying out a series of processes as described above, in addition to the effects of the first embodiment, it is also possible to perform a reduction correction process for the target idle rotation speed, thereby enabling more precise control. In each of the above embodiments, the amount of correction was determined by the number of times the accelerator pedal was pressed, but the same effect can be obtained by directly determining the target idle speed and using it directly in the feedback port and control. be able to.

(Details above) As described above, according to the idle target rotation speed correction method of the present invention, an idle speed control valve is provided, and the idle speed control valve is controlled at the time of starting and idling of the internal combustion engine, and the air bypassing the throttle valve is controlled. When an internal combustion engine equipped with an idle speed control device that adjusts the engine speed is stopped, a correction amount for the idle target speed is calculated based on the number of times the accelerator pedal is depressed, and the idle target speed is adjusted during feedback control based on the correction amount. By setting the rotation speed, the processing of the present invention can be added to the processing of the electronic control device of the internal combustion engine that has been conventionally carried out. The target rotation speed can be adjusted to suit each internal combustion engine, and even if the appropriate idle target rotation speed changes over the years of use of the automobile, it can be easily adjusted.

[Brief explanation of the drawing]

FIG. 1 is a configuration example of an internal combustion engine control system to which the present invention is applied, FIG. 2 is a block diagram of its electronic control circuit, and FIG.
FIG. 4 is a flowchart of the first embodiment of the present invention, FIG. 4 is a flowchart for determining the target idle rotation speed, and FIG. 5 is a flowchart of the second embodiment. 1... Internal combustion engine 10... Throttle valve 12... Bypass path 13... Idle speed control valve (IS
CV> 20...Electronic control circuit 21...Key switch 25...T terminal 26...Idle switch 27...Full open switch agent Patent attorney Tsutomu Adachi and 1 other person

Claims (1)

[Claims] 1. When an internal combustion engine is stopped, it is equipped with an idle speed control valve, and has an idle speed control device that controls the idle speed control valve at the time of starting and idling, and adjusts the air flow rate by bypassing the throttle valve. A method for correcting an idle target rotation speed, the method comprising: calculating a correction amount for the idle target rotation speed based on the number of times a driver pedal is depressed; and setting the idle target rotation speed during feedback control based on the correction amount.