JPH0245487Y2 - - Google Patents

Description

[Detailed Description of the Invention] Industrial Application Field The present invention relates to an idle speed control device for an internal combustion engine.

Conventional technology Idle speed control is an idle speed control provided in a bypass passage that communicates upstream and downstream of the throttle valve during idling operation in which the throttle valve provided in the intake passage of an internal combustion engine continues to operate in a closed state. This is done by controlling the intake air amount of the internal combustion engine using a valve. The output of the internal combustion engine when idling must be set to a different value depending on whether the air conditioner (hereinafter simply referred to as the air conditioner) is activated or not. Control is performed to increase the temperature by a predetermined amount.

However, as shown in the timing chart in Figure 5, in conventional devices of this type, when it is detected that the air conditioner switch is turned on, the opening degree of the idle control valve is increased and the air conditioner compressor is started almost simultaneously. As a result, the idle speed would temporarily drop further than the relatively low idle speed when the air conditioner was not operating, causing the engine to stop.

As a means to solve this problem,
Publication No. 39950 is known. A brief explanation of its contents is as follows. That is, the idle speed control device detects the ON state of the air conditioner switch, immediately increases the idle speed, and operates the air conditioner after a predetermined period of time has elapsed.

(Problems to be Solved by the Invention) However, in this prior art, the predetermined time from turning on the air conditioner switch to starting the air conditioner is kept constant regardless of the engine load condition, so the following new problem arises.

That is, the speed at which the engine speed increases is closely related to the load state of the engine, and the speed at which the engine speed increases is faster in a no-load state than in a loaded state. Therefore, in order to prevent the engine from stalling when the air conditioner is activated using the prior art described above, it is necessary to set the predetermined time to a relatively long time necessary for the engine speed to rise to a necessary and sufficient value under load. . Therefore, even though the engine speed increases immediately when the air conditioner switch is turned on in a no-load state, the operation of the air conditioner is delayed more than necessary, causing discomfort to the passengers.

In addition, under no-load conditions, the engine speed rises more rapidly than necessary, and then settles to the target speed when the air conditioner is activated, so if the air conditioner is delayed, engine operation becomes unstable, which can frighten the driver. That will happen.

The present invention is intended to solve these problems, and aims to prevent the engine from stalling when the air conditioner is activated, and to provide stable engine operation without causing discomfort to passengers when the air conditioner switch is turned on. With the goal.

Means for Solving the Problems In order to solve the above problems, the present invention provides an idle control valve provided in a bypass passage communicating upstream and downstream of a throttle valve of an internal combustion engine, and the basics of the idle control valve. basic control value setting means for setting the opening degree; air conditioner switch state detection means for detecting the ON state of the air conditioner switch; and addition of a correction amount according to the load of the air conditioner compressor to the basic control value when the detection means detects the air conditioner switch state. and a correction means for applying a voltage to the idle control valve, and a delay means for measuring the elapsed time from the time of detection by the detection means and starting the air conditioner compressor when the elapsed time reaches a predetermined time. In the numerical control device, a neutral state detecting means detects whether the transmission is in a neutral state, and in response to an output of the neutral state detecting means, when the transmission is in the neutral state, the predetermined time is set to a shorter value than in other cases. The present invention is characterized in that it is provided with a setting means for correcting.

That is, as shown in FIG. 1, the idle control valve 4 provided in the bypass passage 3 communicating the upstream and downstream of the throttle valve 2 of the internal combustion engine 1 and the basic control for setting the basic opening degree of the idle control valve 4 are used. A value setting means 5, an air conditioner switch state detecting means 7 which detects the ON state of the air conditioner switch 6, and when this detecting means 7 detects, adds a correction amount according to the load of the air conditioner compressor 8 to the basic control value and determines whether the air conditioner is idling. Idle rotation speed, which has a correction means 9 that applies voltage to the control valve 4, and a delay means 10 that measures the elapsed time from the time of detection by the detection means 7 and starts the air conditioner compressor 8 when the elapsed time reaches a predetermined time. The control device includes a setting means 12 for setting the predetermined time to a shorter value when the transmission is in the neutral state than in other cases in response to an output from a neutral state detection means for detecting whether the transmission is in the neutral state. It is set up.

Operation When the air conditioner switch 6 is turned on, the detection means 7 detects that it has been turned on, and the correction means 9 immediately controls the opening degree of the idle control valve to increase, so that the amount of intake air and the engine speed are adjusted to a predetermined amount. Increased. Then, after a predetermined period of time after the engine speed has increased, the air conditioner compressor 8 is activated by the delay means 10, so that even if the engine speed temporarily decreases, the engine speed increases and the engine output increases. After this, an extreme drop in engine speed or engine stoppage can be avoided.

At this time, if the transmission is in a neutral state, the state is detected by the neutral state detection means 11, and the setting means 12 sets the predetermined time to a short value, and if the transmission is not in the neutral state, the predetermined time is set to a longer value. Set to value. Therefore, the start timing of the air conditioner is appropriately controlled according to the load condition of the engine, and stable engine operation can be obtained without causing discomfort to the passenger.

Embodiment FIG. 2 is a block diagram showing an example of the hardware configuration of the present invention. In the figure, 20 is the internal combustion engine main body, and the intake air is passed from the air cleaner 21 to the air flow meter 22 and the throttle chamber 23.
The fuel is supplied to each cylinder from each branch of the intake manifold 24 through the injector 25. The flow of intake air is controlled by a throttle valve 26 in a throttle chamber 23 that is coupled to an access pedal (not shown).
The flow of air during idling passes through a bypass pipe 27 that communicates between the upstream and downstream sides of the throttle valve 26, and an idle control valve 28 provided therein ensures the appropriate amount of air. The idle control valve 28 is
It is composed of a valve body 28a provided in the bypass passage 27, and a stepper motor section 28b that controls the axial position of the valve body 28a in accordance with a signal from a control section 29. As the idle control valve 28, a so-called idle speed control valve can be used, in which the shaft of the valve body is screwed to the rotor of a stepper motor rotated by a stator coil excited by a signal from the control section, and the opening degree by the valve body 28a is This is done by controlling the rotation angle of the stepper motor section 28b.

The control unit 29 includes a CPU 30, a memory 32 connected via a bus 31, an output interface 33, an input interface 34, and an A/D converter 35. The memory 32 stores necessary programs, basic control values, correction values according to load conditions, and the like. The input interface 34 includes an analog output of a throttle opening sensor 36 that detects the opening of the throttle valve 26, an analog output of an engine temperature sensor 37 that detects engine temperature, and an analog output of an engine speed sensor 38 that detects the engine speed. output,
The output of a neutral switch 40, which detects whether the transmission 39 is in a neutral state, and the output of an air conditioner switch 41 are applied, and among these input signals, an analog signal is an A/
The D converter 35 converts it into a digital value. The throttle opening sensor 36 can be a throttle valve switch that detects when the throttle valve 26 is almost fully closed, and the engine temperature sensor 37 is a thermistor-type temperature sensor that detects the temperature of the cooling water in the cylinder. can be used. The output interface 33 sends an injection signal to the injector 25, a control signal to the idle control valve 28, and a start signal to the air conditioner compressor 42.

FIG. 3 is a flowchart showing an example of the software configuration of the present invention.
It is executed every rotation or every predetermined time. CPU3
0 first determines whether the air conditioner switch 41 is on or not (S1), and if it is off, clears the internal counters _{CN1 and CN2} , which are counted up at predetermined time intervals, to zero (S2), and resets the flag A. (S)
3) or turn off the activation signal of the air conditioner compressor 42 (S4). Air conditioner switch 4
If 1 is on, flag A is set (S5),
Determine the state of the neutral switch 40 (S
6). If it is in the neutral state, when the value of the internal counter CN ₂ becomes larger than β, the start signal for the air conditioner compressor 42 is turned on (S7, S11), and if it is not in the neutral state, that is, if it is in the drive state, When the value of internal counter CN ₁ becomes larger than α, the start signal of the air conditioner compressor 42 is turned on (S9, S1
1). Here, α>β. In addition, step S
At step S8, the internal counter _CN2 is preset to β, and at step S10, the internal counter _CN1 is preset to α.

The CPU 30 then detects the engine temperature (S1
2) The basic control value P corresponding to the engine temperature is read from the engine temperature body basic control value pattern stored in advance in the memory 32 (S13). Next, it is determined whether or not it is neutral (S14), and if it is neutral, the basic control value P is set in the register R when the flag A is being reset, and the constant b is set to the basic control value P when the flag A is being set. The added value is set in register R (S15-S17). Also, if it is a drive rather than a neutral, when flag A is being reset, the value obtained by adding a constant a to the basic control value P is set in register R, and when flag A is being set, a constant c is added to the basic control value P. The value is stored in register R.
(S18-S20). Here, the constants a to c have a relationship of a<b<c, where a is the correction amount according to the load when the air conditioner is in the drive state and the air conditioner is not operating, and b is the load when the air conditioner is in the neutral state and the air conditioner is operating. The amount of correction according to c is the amount of correction according to the load in the drive state and when the air conditioner is operating. In step S21, the rotational position of the step motor section 28a of the idle control valve 28 is controlled using the contents of the register R as a target value, and the larger the correction amount, the larger the opening degree of the idle control valve.

Since this embodiment has such a configuration, the fourth
As shown in the figure, when the air conditioner switch 41 is turned on, the opening degree of the idle control valve 28 is increased almost simultaneously to match the load of the air conditioner.
Engine speed increases. Then, the air conditioner compressor 42 is activated after a time period α or β has elapsed since the air conditioner switch 41 was turned on. Therefore, since the air conditioner compressor is started after the engine speed increases, even if the engine speed decreases somewhat, the engine does not stop. The above α is, for example, about 1 to 3 seconds, and β
Since the load is smaller and the engine speed increases faster in the neutral state, the time is set to be smaller than α in order to speed up the air conditioner operation as much as possible.

Although the embodiments of the present invention have been described above, the present invention is not limited to the above embodiments, and various other additions and changes can be made. For example, in the above embodiment, the present invention was applied to an electronic fuel injection type internal combustion engine, but it can also be applied to a carburetor type internal combustion engine that has a function of increasing the engine speed by operating an idle up mechanism when the air conditioner is activated. be. It goes without saying that the idle control valve 28 may also have a structure other than the one described above.

Effects of the Device As explained above, according to the present invention, the time from when the air conditioner switch is turned on until the air is activated is variable depending on whether the air conditioner is in the neutral state or not, so engine stalling occurs when the air conditioner is activated. In addition, even in a neutral state, the operation of the air conditioner is not delayed, so the passenger does not feel uncomfortable, and the engine operation is stabilized.

[Brief explanation of the drawing]

Fig. 1 is an explanatory diagram of the configuration of the present invention, Fig. 2 is a block diagram showing an example of the hardware configuration of the invention, Fig. 3 is a flowchart showing an example of the software configuration of the invention, and Fig. 4 is a diagram of the present invention. FIG. 5 is an explanatory diagram of the operation of the conventional device. 1 is an internal combustion engine, 2 is a throttle valve, 3 is a bypass passage, 4 is an idle control valve, and 6 is an air conditioner switch.

Claims (1)

[Scope of utility model registration request] An idle control valve provided in a bypass passage communicating upstream and downstream of a throttle valve of an internal combustion engine, a basic control value setting means for setting a basic opening degree of the idle control valve, and detecting an on state of an air conditioner switch. Air conditioner switch state detection means;
a correction means that adds a correction amount according to the load of the air conditioner compressor to the basic control value and applies it to the idle control valve when the detection means detects the detection means; and a correction means that measures the elapsed time since the detection of the detection means; An idle rotation speed control device having a delay means for starting an air conditioner compressor when an elapsed time reaches a predetermined time; a neutral state detection means for detecting whether a transmission is in a neutral state; and a neutral state detection means for detecting whether a transmission is in a neutral state. and setting means for adjusting the predetermined time to a shorter value in a neutral state than in other cases in response to the output of the idle speed control device.