JPH0730926Y2 - Confirmation device for idle switch of internal combustion engine - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION <Industrial Application Field> The present invention relates to a confirmation device for an idle switch in an internal combustion engine, and more specifically, by confirming at what idle speed the idle switch is turned on and off, The present invention relates to a device for confirming whether the on / off timing of an idle switch is proper.

<Prior Art> As a throttle valve opening detection device in an internal combustion engine, as shown in Japanese Utility Model Laid-Open No. 59-52045, a continuous signal corresponding to the opening of a throttle valve installed in an intake passage of the engine is provided. There is a potentiometer type throttle sensor that outputs. In this throttle sensor, a contact type that outputs an ON / OFF signal according to the throttle valve opening by driving a movable contact with a cam attached to the valve shaft end of the throttle valve and bringing it into contact with and separating from a fixed contact Of the throttle switch, that is, an idle switch and a full switch.

By the way, in an internal combustion engine, at a dealer or in a development stage, it is confirmed whether the clearance is proper by checking the engine speed only due to air leakage from the clearance formed between the throttle valve and the intake passage inner wall surface. Checking if it is not appropriate due to the influence of foreign matter, and checking at what idle speed the idle switch is turned on and off, and adjusting the idle switch on / off timing appropriately. ing.

In this case, in the internal combustion engine that uses the mechanical idle switch described above, the output signal from the throttle sensor is removed to fix the duty ratio to the electromagnetic coil and clamp the idle speed control. At the same time, the ignition timing at the time of engine idle is fixed, and it is confirmed at what idle speed the above-mentioned idle switch is turned on and off.

<Problems to be solved by the invention> However, in an internal combustion engine using a soft idle switch, the output signal from the throttle sensor is eliminated because the idle position is detected by the output from the throttle sensor. In this state, the on / off state of the idle switch is not known, and it is impossible to confirm at what idle speed the idle switch is turned on / off.

Therefore, in an internal combustion engine using such a soft idle switch, the on / off timing of the idle switch cannot be properly adjusted at the dealer or development stage.

In view of the above-mentioned conventional problems, the present invention is provided with an idle switch that detects the idle operation state of the engine based on the output of the throttle sensor that detects the opening of the throttle valve, a so-called soft idle switch. In an internal combustion engine such as this, it is possible to confirm at what idle speed the idle switch is turned on and off, and to make it possible to properly adjust the on / off timing of the idle switch at the dealer and development stages. And

<Means for Solving the Problems> Therefore, according to the present invention, a bypass passage that bypasses a throttle valve interposed in the intake passage is provided in the intake passage of the engine, and the bypass passage is energized to an electromagnetic coil. Of the throttle sensor for detecting the opening of the throttle valve while interposing an auxiliary air valve for idle speed control, which is operated by a balance between the valve opening force by the valve and the valve closing force by the spring. In an internal combustion engine including an idle switch that detects an idle operation state of the engine based on an output, a self-diagnosis device and an idling speed by fixing a duty ratio for energizing the electromagnetic coil during monitor control of the self-diagnosis device. Idle speed control clamp means for clamping control, and idle time ignition timing for fixing engine idle time ignition timing during the monitor control A fixing means is provided so that it can be confirmed at what idle speed the idle switch is turned on and off.

<Operation> In such a configuration, during monitor control of the self-diagnosis device,
The duty ratio for energizing the electromagnetic coil is fixed to clamp the idle speed control, and the ignition timing at the engine idle time is fixed.

Therefore, it is possible to confirm at what idle speed the idle switch is turned on and off, and it is possible to properly adjust the on / off timing of the idle switch at the dealer and the development stage.

<Embodiment> An embodiment of the present invention will be described below with reference to the drawings.

In FIG. 2, air is sucked into the engine 1 through an air cleaner 2, a throttle body 3 that forms an intake passage, and an intake manifold 4. Inside the throttle body 3, a throttle valve 5 that interlocks with an accelerator pedal (not shown) is provided, and a fuel injection valve 6 is provided upstream thereof. The fuel injection valve 6 is opened by being energized by a drive pulse signal from a control unit 13, which will be described later, to inject and supply fuel adjusted to a predetermined pressure. Further, a bypass passage 7 is provided in the throttle body 3 so as to bypass the throttle valve 5, and an auxiliary air valve 8 for idle speed control is provided in the bypass passage 7. The auxiliary air valve 8 operates by a balance between a valve opening force caused by energization of the electromagnetic coil 8a and a valve closing force caused by a return spring (not shown), and is controlled to have an opening degree according to the energization current to bypass the throttle valve 5. And supply auxiliary air.

A spark plug 9 is provided in the combustion chamber of the engine 1.

A high voltage generated in the ignition coil 10 is applied to the spark plug 9 based on an ignition signal from the control unit 13 via the distributor 11, whereby spark ignition is performed to ignite and burn the air-fuel mixture. Exhaust gas is discharged from the engine 1 through an exhaust manifold 12.

The control unit 13 is a microcomputer including a CPU, ROM, RAM and an input / output interface.
14 is provided and receives input signals from various sensors and performs arithmetic processing as described later to control the operation of the fuel injection valve 6 and the auxiliary air valve 8.

As the various sensors, the throttle valve 5 is provided with a throttle sensor 15, which outputs a voltage signal corresponding to the opening α of the throttle valve 5 and an idle position signal of the throttle valve 5. Plays the function of a switch.

A crank angle sensor 17 is built in the distributor 11 and outputs a position signal for every 2 ° of crank angle and a reference signal for every 180 ° of crank angle, and the engine speed N is based on these signals. Is calculated.

The exhaust manifold 12 is provided with an O ₂ sensor 18. The O ₂ sensor 18 is a known sensor for air-fuel ratio feedback control in which the electromotive force suddenly changes when the air-fuel mixture is burned at the stoichiometric air-fuel ratio.

In addition, a water temperature sensor 19 that detects the engine cooling water temperature Tw, a neutral switch 20 that is turned on at the neutral position of the transmission, a vehicle speed sensor 21 that detects the vehicle speed VSP, and the like are provided.

Here, the CPU of the microcomputer incorporated in the control unit performs arithmetic processing according to the program (idle rotation speed control routine, fuel injection amount control routine) on the ROM to control the idle rotation speed and the fuel injection amount.

Further, the microcomputer incorporated in the control unit includes a self-diagnosis device and an idle rotation speed control clamp for clamping the idle rotation speed control by fixing the energization duty ratio to the electromagnetic coil 8a during monitor control of the self-diagnosis device. The means also serves as an idle time ignition timing fixing means for fixing the engine idle time ignition timing during the monitor control.

Next, the idle switch confirmation routine by these means will be described with reference to the flowchart of FIG.

In step (hereinafter abbreviated to S as in the figure) 1, the monitor control state of the self-diagnostic device is determined, and during monitor control (when ON), the process proceeds to S2, and the auxiliary air valve in idle speed control No. 8 electromagnetic coil 8a energizing duty ratio IS
Cduty is fixed to the idle speed control soft clamp value SOFCL to clamp the idle speed control and open the engine idle time ignition timing control to fix the ignition timing. When the monitor is not controlled by S1 (OFF), S3
Proceed to step 2 to execute normal idle speed and engine idle time ignition timing control.

According to such a configuration, during monitor control of the self-diagnosis device,
As a result of fixing the duty ratio of energization to the electromagnetic coil 8a to clamp the idle speed control and fixing the ignition timing control at the time of engine idle, the idle detecting the idle operating state of the engine based on the output of the throttle sensor. Even in a system equipped with a switch, it is possible to confirm at what idle speed the idle switch is turned on and off, and it is possible to properly adjust the on / off timing of the idle switch at the dealer and development stages. .

<Effects of the Invention> As described above, according to the present invention, the so-called soft idle switch that detects the idle operation state of the engine based on the output of the throttle sensor that detects the opening of the throttle valve is used. In an internal combustion engine, it is possible to easily and reliably confirm at what idle speed the idle switch is turned on and off, and it is possible to properly adjust the on / off timing of the idle switch at the dealer and development stages. Becomes

[Brief description of drawings]

FIG. 1 is a block diagram of an internal combustion engine idle switch confirmation device according to the present invention, FIG. 2 is a system diagram showing an embodiment of the present invention, and FIG. 3 is a flowchart of an idle switch confirmation routine. 1 ... Engine, 5 ... Throttle valve, 6 ... Fuel injection valve, 7
... Bypass passage, 8 ... Auxiliary air valve, 8a ... Electromagnetic coil, 9
… Spark plug, 13… Control unit, 14… Microcomputer, 15… Throttle sensor

Claims (1)

[Scope of utility model registration request] A bypass passage for bypassing a throttle valve interposed in the intake passage is provided in the intake passage of the engine, and the bypass passage has a valve opening force by energizing an electromagnetic coil and a valve closing force by a spring. While the auxiliary air valve for idle speed control, which is operated in a balanced manner and whose opening is controlled, is installed, the idle operating state of the engine is detected based on the output of the throttle sensor that detects the opening of the throttle valve. In an internal combustion engine equipped with an idle switch, a self-diagnosis device, and idle speed control clamp means for fixing the duty ratio to the electromagnetic coil and clamping idle speed control during monitor control of the self-diagnosis device. An idle time ignition timing fixing means for fixing the engine idle time ignition timing during the monitor control,
A confirmation device for an idle switch in an internal combustion engine, characterized in that it can be configured to confirm at what idle speed the idle switch is turned on and off.