JPS62251448A - Idle rotational speed regulating method - Google Patents

Abstract

PURPOSE:To smoothly confirm whether a desired rotational speed is changed or not, by making the actuating speed of an actuator faster, when an external signal is inputted, than when no external signal is inputted. CONSTITUTION:When an engine is in an idle condition, if an external switch 41 is turned on so that an external input is delivered, the present desired rotational speed NE is corrected with a correcting value f(Vout) which is indicated as a function of voltage values (Vout) which are delivered from a volume 43 and are A/D-converted, and therefore, a new desired rotational speed NE0 is computed. Further, when the present desired rotational speed NE is greater than the new desired rotational speed NE0, a pulse motor 16A is controlled so that an idle control (ISC) valve 16B is closed at an actuating speed V1. This actuating speed is set to a value which is higher than a normal actuating speed V2 of the ISC valve. Further, when NE<NE0, the valve is opened at the speed V1. Further, when no external input is delivered, the ISC valve is controlled to be opened and closed at the actuating speed V2.

Description

Detailed Description of the Invention (Industrial Application Field) The present invention relates to a method for adjusting the idle speed! The present invention relates to an idle rotation speed adjustment method for adjusting the idle rotation speed by controlling an actuator so that the idle rotation speed becomes the changed target rotation speed.

[Conventional technology]

Conventionally, a bypass is provided to communicate the upstream and downstream sides of the throttle valve, and an idle control (ISC) valve is attached to this bypass.
The idle rotation speed is controlled to a predetermined target rotation speed by controlling the O-pulp using a microcomputer to control the amount of air flowing into the bypass passage. In other words, a predetermined target rotational speed is stored in the read-only memory (ROM) of a microcomputer according to the on/off status of the air conditioner, the position of the automatic transmission shift lever, etc., and the engine rotational speed is also detected. ,°? The engine speed at idle is controlled so that it reaches the target speed. However, ISO
The idle speed may not be able to be controlled to the target speed due to manufacturing errors in the pulp, engine, etc., or deposits due to changes over time.

For this reason, in the past, the voltage divided by resistors was input to the microcomputer via an analog-to-digital converter, and the resistors were assembled (by changing the voltage value to change the target rotation speed, or the input board of the microcomputer The target rotation speed is changed according to the level of the human-powered boat by inputting No. 3 for changing the rotation speed.Also, a volume is installed in the microcomputer, and the target rotation is changed according to the output value of the volume. The number has been changed (Japanese Utility Model Publication No. 58-144042).

In this way, each time you change the target rotation speed, the engine rotation speed at idle changes, so adjust the idle rotation speed by changing the target rotation speed while visually checking the displayed value on an engine rotation speed detector such as a tachometer. be able to.

[Problem that the invention seeks to solve]

However, with the conventional method described above, it is necessary to change the resistance to change the voltage input to the analog-to-digital converter, and it is necessary to recombine the wiring to input the signal for changing the rotation speed to the human-powered boat. Since it is necessary to replace
There was a problem that reliability and workability decreased. In addition, when changing the target rotation speed by adjusting the volume, the ISC valve moves slowly in response to changes in the output value of the volume, so it is necessary to check whether the engine rotation speed matches the changed target rotation speed. It takes time to check whether
There was a problem.

The present invention has been made to solve the above-mentioned problems, and an object of the present invention is to provide an idle rotation speed adjustment method that can quickly confirm whether or not the target rotation speed has been changed.

Means for Solving Problem c] In order to achieve the above object, the present invention changes the target rotation speed based on the idle rotation speed adjustment signal when an external signal is input, and adjusts the idle rotation speed. In the idle rotation speed adjustment method of adjusting the idle rotation speed by controlling an actuator to reach a changed target rotation speed, when the external signal is inputted, the input speed is higher than when the external signal is not manually input. It is characterized by an increased operating speed of the actuator.

[Function] According to the present invention, when an external signal is manually input, the target rotation speed is changed based on the idle rotation speed adjustment signal, and the actuator is adjusted so that the idle rotation speed becomes the changed target rotation speed. is controlled. When the above external input (No. 3) is not input, the actuator is controlled faster than the normal operating speed. Since the operating speed of the actuator is increased in this way, the engine speed matches the changed target speed. You can quickly check whether or not you have done so.

〔Effect of the invention〕

As explained above, according to the present invention, the operating speed of the actuator is increased when an external signal is manually input, so it is possible to quickly determine whether or not the engine speed matches the changed target speed. This has the effect that the idle speed can be adjusted quickly.

[Explanation by c.]

Here, in internal combustion engines, there are those that control the ignition timing with a fixed ignition advance angle when idling, and those that control the ignition timing with an ignition advance angle that changes depending on the engine speed when idling. In addition, when using a terminal (T terminal) for engine control microcomputer self-diagnosis as a switch for external No. 13 input, the T terminal is also used for initial setting of the ignition time. In any of the above-mentioned internal combustion engines, the ignition time is controlled by a fixed ignition advance angle when the T terminal is on (at the time of grounding).

For this reason, in an internal combustion engine in which the ignition time is controlled by the ignition advance angle that changes depending on the engine speed at idle, T
If the idle speed adjustment method of the above invention is carried out by manually inputting an external signal using a terminal, the idle speed will be adjusted when the T terminal is on (ignition timing is fixed), so when the T terminal is off, The ignition advance angle is changed (the ignition advance angle is changed to +HiH according to the engine speed), and as a result, the idle speed changes in accordance with the changed ignition advance angle.

Therefore, in an aspect of the present invention, the target rotation speed is changed based on the idle rotation speed adjustment signal when an external signal is input, and the actuator is controlled so that the idle rotation speed becomes the changed target rotation speed. Idle rotation & 5 to adjust the idle rotation speed with iB! The adjustment method is characterized in that the ignition timing is controlled based on a normal idle ignition advance angle when the external signal is input.

According to this aspect, the target rotation speed is changed based on the idle rotation speed adjustment signal when the external signal is inputted manually, and the idle rotation speed becomes the changed target rotation speed. The actuator is controlled. When the external signal is manually input, the ignition timing is controlled based on the normal idle ignition advance angle. If the T terminal is used for external signal input in an internal combustion engine that changes depending on the engine speed at idle, the ignition timing will be based on the normal idle ignition advance angle even when the T terminal is on. Therefore, after adjusting the idle speed and turning off the T terminal, the ignition timing does not change, and therefore the idle speed does not change.

As explained above, according to this aspect, when an external signal is input, the control is performed using the normal idle ignition advance angle? Since the idle speed can be adjusted using the J-shaft, the idle speed will not change even if the external signal is stopped and the idle ignition advance angle returns to the normal idle ignition advance angle. Even in an internal combustion engine that controls the ignition timing and uses a fixed ignition advance angle when an external signal is input, the idle speed can be easily adjusted.

〔Example〕

Embodiments of the present invention will be described in detail below with reference to the drawings.

FIG. 2 shows an internal combustion engine to which the present invention can be applied. A throttle valve 8 is disposed downstream of an air cleaner (not shown), and the throttle valve 8 has a fully closed state B ( An idle switch 10 that is turned on at idle position) is attached, and a surge tank 12 is provided downstream of the throttle valve 8. A semiconductor strain resistance type pressure sensor 6 equipped with a filter having a time constant of about 3 to 55 seconds is attached to the surge tank 12. Further, a bypass passage 14 is provided so as to bypass the throttle valve 8 and communicate the upstream side of the throttle valve with the surge tank 12 on the downstream side of the throttle valve. This bypass path 14 is connected to a pulse motor 1 equipped with a four-pole stator.
An idle speed control (ISO) valve 16B whose opening degree is adjusted by 6A is installed.

The surge tank 12 communicates with the combustion chamber of the engine 20 via an intake manifold 18 and an intake port 22. A fuel injection valve 24 is attached to the intake manifold 18 for each cylinder or for each cylinder group so as to protrude into the intake manifold.

The fuel chamber of the engine 20 is communicated via an exhaust port 26 and an exhaust manifold 28 to a catalyst device (not shown) filled with a three-way catalyst. This exhaust manifold 28 outputs an air-fuel ratio signal that is inverted at the residual oxygen concentration in the exhaust gas corresponding to the stoichiometric air-fuel ratio.
□Sensor 30 is attached. engine block 3
A cooling water temperature sensor 34 is attached to the engine block 2 so as to penetrate through the engine block 32 and protrude into the walk jacket. This cooling water temperature sensor 34 detects the engine cooling water temperature and outputs a water temperature signal.

A spark plug 3B is attached to each cylinder so as to penetrate the cylinder head 36 of the engine 20 and protrude into the combustion chamber. The spark plug 38 is connected via a distributor 40 and an igniter 42 to an electronic control circuit 44 composed of a microcomputer or the like.

Inside the distributor 40, a cylinder discrimination sensor 46 and a rotation angle sensor 48 are installed, each of which is composed of a signal rotor fixed to the distributor shaft and a pickup fixed to the distributor housing. In the case of a 6-cylinder engine, the cylinder discrimination sensor 46 is, for example, ? Cylinder discrimination (No. 3 is output) every 20"cA (crankshaft angle), and the rotation angle sensor 48
Outputs an engine rotation speed signal every degree CA.

An external switch 41 for inputting an external signal is connected to the electronic control circuit 44, and a volume 43 for adjusting the target value of the idle rotation speed is attached.

As shown in FIG. 3, the electronic control circuit 44 includes a central processing unit (MPU) 60 and a read-only memory (ROM).
62, random access memory (RAM) 64, backup RAM (BU-RAM) 6G, input/output capotro 8, manual port door 01 output port door 2.74.76, and buses such as data bus and control bus that connect these. 78. The input/output capotro 8 is connected to a pressure sensor 6, a cooling water temperature sensor 34, and a volume 43 via an analog-digital (A/D) converter 78, a multiplexer 80, and buffers 82, 83, and 84.
is connected. MPU60 is multiplexer 80
and A/D transformer 78 to sequentially convert the pressure sensor 6 output, water temperature sensor 34 output, and volume 43 output into digital signals and store them in the RAM 64. The manual port door 0 has a comparator 88 and a buffer 86.
02 sensor 30 is connected via the cylinder discrimination sensor 46 and rotation angle sensor 4 via the waveform shaping circuit 90.
8 is connected, and an idle switch 10 and an external switch 41 are also connected. The output port door 2 is connected to the igniter 42 via a drive circuit 92, the output port door 4 is connected to the fuel injection valve 24 via a drive circuit 94, and the output port door 6 is connected to the ISO via a drive circuit 96.
It is connected to the SC bulb motor 16A.

Note that 98 is a clock and 100 is a timer. The above RO
The M62 stores in advance a control routine program, etc., which will be explained below.

Next, a method for adjusting the idle speed will be explained while explaining a control routine of an embodiment in which the present invention is applied to the above engine.

FIG. 1 shows a control routine for the ISC pulp according to this embodiment. In step 110, it is determined whether the idle switch 10 is on or not, thereby determining whether or not the engine is in an idle state. When the idle state is determined in step 110, the voltage value Vout outputted from the volume 43 and A/D converted is fetched in step 112, and in step 114, whether or not the external switch 41 is operated and turned on is determined. That is, it is determined whether an external signal is input. If the external switch 41 is on, the current target rotation speed NE is determined in step 116. The voltage value Vou
A new target rotation speed is calculated by correcting it using a correction value f (Vout) expressed as a function of t.

Since the correction value f (Vout) is expressed by the output voltage value Vout of the volume, the target rotational speed NEO is changed by rotating the volume knob to adjust the output voltage value Vout.

In the next step 118, the current engine speed NE and the target speed NE changed as described above are determined.

If NE≧NEo, the step motor is controlled in step 120 to close at the ISOSC valve operating speed v1. This operating speed v1 is normal IS
The operating speed V of the C valve has been made faster! The operating speed of the SC valve can be achieved by reducing the frequency of the signal that controls the step motor. On the other hand, when it is determined in step 118 that N E <N Eo, the ISC valve is controlled to open at the operating speed V in step 122.

When it is determined in step 114 that the external switch is off,
That is, during normal idling, the target engine speed N8° is corrected with the correction value f (Vout) in step 124, and the current engine speed NE and target engine speed N E o are compared in step 126.

Then, when it is determined that NE≧NE, step 12
At step 8, the ISOSC valve is controlled to close at the normal operating speed vt, and when it is controlled that N E <NE, the ISC valve is controlled to open at the normal operating speed v2 at step 130.

As mentioned above, when the external switch is on, the SC valve is controlled at a faster speed than when the external switch is off;
The idle speed changes as shown in FIG. 4 in accordance with the adjustment of one neem. Note that the solid line in FIG. 4 shows the change in the voltage value Vout output from the volume.

As explained above, in this embodiment, since the operating speed of the ISC valve is increased, it is possible to quickly check the change in the target rotation speed with respect to the output voltage value of the volume, and after adjusting the idle rotation speed, the When the switch is turned off, the operating speed of the ISC valve is slowed down, so even if the output voltage value of the volume fluctuates greatly due to electrical noise, vibration, etc., the idle speed will not fluctuate rapidly. Note that a T terminal can be used as the above external switch.

Next, another embodiment of the present invention will be described with reference to FIG.
This example corresponds to an aspect of the present invention. Note that in FIG. 5, the same parts as in FIG. 1 are designated by the same reference numerals, and explanations thereof will be omitted.

In this embodiment, an external signal is input using a T terminal as an external switch, and when it is determined in step 114 that the T terminal is on, step 13
2, the output voltage 1/7VouL of the volume becomes the predetermined value V
Exceeded max. Determine whether there are two. This predetermined value Vmax is determined to correspond to the voltage value when the operating angle θ1 of the volume is close to the maximum. At idle, the engine speed GN is as shown in Figure 8.
In an engine that controls the ignition timing based on the ignition advance angle THT, which changes according to The idle speed is adjusted by controlling the volume.

In step 132, the output voltage value Vout is set to a predetermined value V wa
If it is determined that x has been exceeded, step 1
At step 34, the ignition timing is controlled by the ignition advance angle THT shown in FIG. Controls the ISC valve with fast operating speed. If the judgment in step 132 is negative, the ignition timing is controlled with a fixed ignition advance angle in step 138, and the process proceeds to step 136.In this way, if the volume is not rotated to the maximum operating angle, the ignition timing is controlled with a fixed ignition advance angle. Therefore, the ignition timing can be adjusted using a timing light.

In addition, in an engine that is controlled with a fixed ignition advance angle at idle, there is no need to rotate the volume to the maximum operating angle, and in this case, steps 132 to 13
Since the process proceeds to step 136 via step 8, the idle speed can be adjusted. FIG. 7 shows the change in the target rotational speed N E o when the volume is rotated to a large-volume operation angle.

As explained above, in this example, after the volume is rotated to the maximum operating angle, control is performed using the normal idle ignition advance angle, so it is necessary to provide a new switch for adjusting the rotation speed at the idle. There is no T#A again
Even in the child-on state, the ignition timing can be controlled using both the fixed ignition advance angle and the normal ignition advance angle.

[Brief explanation of drawings]

FIG. 1 is a flowchart showing an ISC valve control routine according to an embodiment of the present invention, FIG. 2 is a schematic diagram of an engine to which the present invention can be applied, and FIG. 3 is a block diagram showing details of the control circuit shown in FIG. FIG. 4 is a diagram showing changes in volume output and idle rotation speed, FIG. 5 is a flowchart showing an ISC valve control routine according to another embodiment of the present invention, and FIG. 6 is a diagram showing changes in output voltage with respect to volume operation angle. FIG. 7 is a diagram showing changes in target rotational speed with respect to volume output voltage, and FIG. 8 is a diagram showing a map of idle ignition advance angle. IGB...lSC valve 41...External switch 43...Volume

Claims (1)

[Claims] (1) When an external signal is input, the target rotation speed is changed based on the idle rotation speed adjustment signal, and the actuator is controlled so that the idle rotation speed becomes the changed target rotation speed. An idle rotation speed adjustment method for adjusting an idle rotation speed, characterized in that when the external signal is input, the operating speed of the actuator is made faster than when the external signal is not input.