JPH03237252A - Engine control device - Google Patents

Abstract

PURPOSE:To prevent the disorder of control by performing control without using a detection signal at the time of external electromagnetic waves over the specified value acting upon a detecting part in the case of controlling the engine operating state most appropriately by a control part on the basis of the engine operating state detected by the detecting part. CONSTITUTION:The microcomputer 2a of a control part 2 obtains air flow, rotating speed, and the like on the basis of the data inputted from the air flow detector 1a of a detecting part 1 through an A/D converter 2c, the data inputted from the rotating speed detector 1b of the detecting part 1 through an A/D converter 2d, the reference control data from a storage circuit 2b, and the like. The microcomputer 2a then controls a fuel injection valve control circuit 3a, an ignition timing control circuit 3b, and the like in an operating part 3. In this case, when strong faulty electromagnetic waves from outside act upon the air flow detector 1a, for instance, the air flow detector 1a becomes abnormal, and its detected data results in error. In order to cope with this, the abnormal state is judged by the microcomputer 2a, and an engine is controlled without using wrong detected data.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to an engine control device, and particularly to ensuring stability of control against electromagnetic waves (radio noise) acting on the control device from the outside.

[Conventional technology]

Despite the fact that automobile engines are operated under complex conditions, demands for improved fuel efficiency and exhaust gas purification are increasing. In order to meet this demand, for example,
As described in Publication No. 219859, the operating state of the engine is detected, and this detection signal (data) is processed using the data processing function of the control unit using a microcomputer, so that the engine is in the optimal operating state. A control device has been proposed that operates control elements so that

[Problem to be solved by the invention]

The control section of this conventional control device processes the unique control reference data stored in advance inside the control device and the detection signal (detection data) input from the detection section to control the engine to achieve the optimum operating state. obtains data and therefore
If the detection data obtained from the detection section is disturbed by the influence of electromagnetic waves output from a high-power radio device or the like, control accuracy will be reduced, the rotational speed of the engine will be disturbed, and furthermore, the engine will stop.

Therefore, an object of the present invention is to propose a control device in which control is less likely to be disrupted by the influence of electromagnetic waves acting from the outside.

[Means to solve the problem]

In order to achieve this object, the present invention provides an engine control device comprising a detection means for detecting the operating state of an engine, and a control section for controlling the engine to an optimal operating state based on an operating state detection signal from the detection means. The control unit is characterized in that when an electromagnetic wave of a predetermined value or more acts on the detection means from the outside, the control section controls the operation of the engine independently of the detection signal from the detection means.

[Effect]

Even if the detection means generates a disturbed detection signal due to the influence of external electromagnetic waves, the control section does not use this disturbed detection signal as control data, so the engine operation control is not significantly disturbed.

〔Example〕

Hereinafter, the present invention will be described in detail with reference to the drawings.

FIG. 1 is a block diagram of the entire engine control device, in which ``■'' is a detection section that detects the operating state of the engine, 2 is a control section, and 3 is an operation section that operates the engine operation control elements.

The detection unit 1 includes, for example, an air flow rate detector 1a that detects the intake air flow rate to the engine, a rotation speed detector 1b that detects the rotation speed, a throttle position sensor lc that detects the opening degree of the throttle valve, and the like. The control unit 2 includes, for example, a microcomputer 2a that executes data processing for engine control and an RO that stores control reference data.
A/D conversion circuits 2c, 2d, 2e, etc. that convert analog detection signals coming from each detector into digital detection signals (detection data) are provided.

The operation unit 3 includes, for example, a fuel injection valve control circuit 3a, an ignition timing control circuit 3b, a throttle control circuit 30, and the like.

In the above configuration, the microcomputer 2a of the control unit 2 receives the air flow rate detection data V input from the air flow rate detector 1a via the A/D conversion circuit 2C and the A/D conversion circuit 2d from the rotational speed detector 1b. The air flow rate and rotational speed are determined from the rotational speed detection data N inputted via the storage circuit 2b and the control reference data stored in the storage circuit 2b, and the optimal fuel injection amount and optimal ignition timing are determined and the fuel injection valve control circuit 3a and ignition timing control circuit 3b, or throttle control circuit 3C to bring the engine into optimal operating condition.

In such an optimal operation control state, when a strong interference electromagnetic wave acts on the air flow rate detector 1a from the outside, the magnitude of the air flow rate detection data output from the air flow rate detector 1a increases from the magnitude in the normal state. The values are far different, and if this detected data is used to control engine operation, the operating state will be disturbed.

In this embodiment, in such a case, the microcomputer 2a determines that the air flow rate detection data V is in an abnormal state, and executes engine control without using the abnormal air flow rate detection data.

FIG. 2 shows a data processing flow executed by the microcomputer 2a to perform such engine control. This data processing is repeatedly executed at each fuel injection timing synchronized with engine rotation.

In processing step 201, air flow rate detection data (2) and rotational speed detection data (N) are read and stored in the work memory.

The processing switch 202 determines whether the read detection data V is within a predetermined range between the minimum value (2) and the maximum value V (control reference data) that change under normal conditions. If it is within the range, it is determined that the detection state is normal and the process moves to step 203 for normal operation control, and if it is outside the range, it is determined that the detection state is abnormal and the process moves to process step 204 for emergency operation control.

In processing step 203, the intake air flow rate Q is calculated from the air flow rate detection data (2). This is the intake air flow rate Q for each air flow rate detection data V stored in advance in the memory circuit 2b.
This can be achieved by searching the table and reading out the corresponding data.

Next, in process step 205, the air-fuel ratio for optimal engine operation is determined. This process can also be performed by searching a table stored in advance in the memory circuit 2b.

Furthermore, in processing step 206, a fuel injection amount for achieving the optimum air-fuel ratio is calculated. This process is also performed in advance by the memory circuit 2.
This can be done by searching the table stored in b.

Then, in processing step 207, a control signal for injecting the calculated fuel injection amount is output.

In processing step 204, throttle control processing is performed with reference to the rotational speed detection data N. This throttle control processing adjusts the engine output to maintain the rotational speed detection data N read in processing step 201 based on the fuel injection amount using the air flow detection data V used in the previous fuel injection control. This is a process of controlling the throttle control circuit 3C so as to obtain the desired throttle opening.

According to the engine control described above, the air flow rate detector 1
Even if the air flow rate detection signal V input from a through the A/D conversion circuit 2C becomes abnormal due to the influence of external electromagnetic waves, the operating state of the engine will be greatly disturbed (control accuracy may be affected). There is no disturbance in rotational speed or engine stoppage due to a drop in rotation speed.

FIG. 3 shows that a field strength measuring device 1d detects harmful electromagnetic waves acting on an air flow rate detector 1a from the outside, and the detection signal is sent to a microcomputer 2 via an A/D conversion circuit 2f.
Fig. 2 shows an embodiment in which normal operation control and emergency operation control are switched by determining whether electromagnetic waves strong enough to cause an abnormality to appear in air flow rate detection data are acting on the data processing of the microcomputer 2a.

According to this embodiment, switching between normal operation control and emergency operation control can be performed more accurately.

FIG. 4 shows an embodiment in which the detection data V output from the air flow rate detector 1a is preprocessed and then provided to the microcomputer 2a via the A/D conversion circuit 2C.

The preprocessing circuit for the preprocessing includes a storage circuit 1e such as a ROM that stores detection data output by the air flow rate detector 1a during normal operation and control reference data indicating the intake air flow rate Q for each air flow rate detection data; A memory circuit 1f that temporarily stores the detection data (■) output from the air flow rate detector 1a.
Then, the air flow rate detection data V read from the air flow rate detector 1a is compared with the normal detection data stored in the storage circuit 1e to determine whether it is normal or abnormal. The flow rate detection data V is stored in the temporary storage circuit 1f, and the air flow rate detection data (2) is stored in the storage circuit 1e.
The intake air flow rate Q is determined and outputted with reference to , and in case of abnormality, the air flow rate detection data V stored in the - hour memory circuit if immediately before is read out, and the intake air flow rate is determined with reference to the memory circuit 1e. and an arithmetic circuit 1g that calculates and outputs Q.

This embodiment can reduce the control data processing load on the microcomputer 2a.

In the above embodiment, the intake air flow rate Q of the engine is calculated based on the detection data from the air flow rate detector 1a, but it can also be calculated based on the intake pipe pressure detection. The negative effects of electromagnetic waves can also be reduced in the same way.

〔Effect of the invention〕

As described above, in the present invention, even if the detection means generates a detection signal that is disturbed due to the influence of electromagnetic waves acting from the outside, the control section does not use this disturbed detection signal as control data, so that engine operation control is greatly improved. This results in a control device that is not disturbed and whose control is less likely to be disturbed by the influence of electromagnetic waves acting from the outside.

[Brief explanation of drawings]

The drawings show an embodiment of the present invention, and FIG. 1 is a block diagram of the entire engine control device, and FIG. 2 is a data processing flowchart for fuel injection amount control executed by a microcomputer to control the engine. FIGS. 3 and 4 are block diagrams of main parts of other embodiments. 1...detection section, 1a...air flow rate detector, 1b...rotation speed detector, 2
...Control unit, 2a...Microcomputer, 2b...Memory circuit, 3.
......Operation unit, 3a...Fuel injection valve control circuit, 3b...Ignition timing control circuit,
3c...Throttle control circuit. Figure 1 Figure 2 Figure 3 Figure 4

Claims (1)

[Scope of Claims] 1. An engine control device comprising a detection means for detecting the operating state of an engine, and a control section for controlling the engine to an optimum operating state based on an operating state detection signal from the detection means, An engine control device characterized in that when an electromagnetic wave of a predetermined value or more acts on the detection means from the outside, the control section controls the operation of the engine independently of the detection signal from the detection means. 2. In claim 1, the detection means:
An engine control device characterized in that it is an air flow rate detector that detects the intake air flow rate of an engine. 3. In claim 1, the detection means:
An engine control device characterized in that it is a pressure detector that detects pressure inside an intake pipe of an engine. 4. A first detecting means for detecting the intake air flow rate of the engine, a second detecting means for detecting the rotational speed of the engine, and detecting the engine based on the detection signals from the first and second detecting means. In the engine control device, the control unit includes a control unit that controls the fuel injection amount to achieve an optimal operating state, when an electromagnetic wave of a predetermined value or more acts on the first detection unit from the outside, the control unit controls the first detection unit. Engine control characterized in that throttle control is performed to maintain the engine rotational speed at that time based on the detection signal from the second detection means, independently of the detection signal from the second detection means. Device. 5. An engine control device comprising an operating state detecting means for detecting the operating state of the engine, and a control unit controlling the engine to an optimum operating state based on an operating state detection signal from the operating state detecting means, Electric field strength detection means is provided for detecting the magnitude of electromagnetic waves acting on the state detection means, and the control section refers to the detection signal from the electric field strength detection means and detects a signal from the outside to the operating state detection means of a predetermined value or more. An engine control device characterized in that when electromagnetic waves act on the engine, the engine operation is controlled independently from the detection signal from the operating state detection means. 6. An engine control device comprising a detection means for detecting the operating state of the engine, and a control section for controlling the engine to an optimal operating state based on an operating state detection signal from the detection means, wherein the detection means is externally connected to the engine. When the electromagnetic wave acting on the detection means is less than a predetermined value, the detection signal at that time is output and temporarily stored, and when it is greater than the predetermined value, the detection signal stored immediately before is output. Engine control device.