JP2002250250A - Internal combustion engine control device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To securely stop an internal combustion engine when a part of CPUs operates wrongly in an internal combustion engine control device with plural CPUs for controlling the internal combustion engine together with other objects to be controlled. SOLUTION: Plural CPUs 702 and 703 are connected to each other via a communication line 707, and a CPU abnormal operation detecting means for detecting abnormality of the operation of the other CPU is mounted in each CPU. Further, an engine stopping means is mounted in each CPU for stopping the internal combustion engine 4 when each CPU detects abnormality in the operation of the other CPU by the CPU abnormal operation detecting means.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a control device for an internal combustion engine having a plurality of CPUs for controlling the internal combustion engine together with other control objects.

[0002]

2. Description of the Related Art As a control device for controlling the ignition timing of an internal combustion engine, an ignition timing is calculated by a CPU for various control conditions, and an ignition operation is performed when the calculated ignition timing is detected. Things are used. Further, a fuel valve is provided in a fuel supply path for supplying fuel to the internal combustion engine, and the opening and closing of the fuel valve is controlled by a CPU.

Further, in a system having an internal combustion engine and another control target, the same control device controls the internal combustion engine and another control target.

As described above, even when a plurality of control objects are controlled, if the system scale is relatively small, control can be performed by a single CPU. When a heat pump is driven by an internal combustion engine to perform air conditioning, such as a gas heat pump (GHP), the size of the system is large, and it is necessary to control many control targets in addition to the ignition device for the internal combustion engine. , CP
Due to the number of ports of U and processing capacity, multiple CPUs
Is often used to control each CPU.

[0005]

As described above, when the internal combustion engine is controlled together with other control objects by the control device having a plurality of CPUs, when the operation of some CPUs becomes abnormal due to noise or the like. Since the control operation of the entire system is not properly performed, it is necessary to temporarily stop the operation of the entire system including the internal combustion engine and take measures for returning to a normal state.

However, in a conventional control device that controls an internal combustion engine together with other control objects by a control device having a plurality of CPUs, even if the operation of some CPUs becomes abnormal, the control operation by the other CPUs is performed. The control operation of the internal combustion engine may be continued as it is when the operation of the CPU that controls a control target other than the internal combustion engine becomes abnormal, and the operation of the engine is stopped. There was a problem that it could not be done.

SUMMARY OF THE INVENTION It is an object of the present invention to provide an internal combustion engine control apparatus that includes a plurality of CPUs and controls the internal combustion engine together with other control objects. To be able to do it.

[0008]

According to the present invention, a plurality of CPUs are provided.
The present invention relates to an internal combustion engine control device that controls an internal combustion engine together with other control objects using the same.

In the present invention, a plurality of CPUs are interconnected via a communication line, and each CPU is provided with CPU operation abnormality detecting means for detecting an abnormality in the operation of another CPU.

Further, all the CPUs are provided with engine stop means for stopping the internal combustion engine when the CPU operation abnormality detection means detects an abnormality in the operation of another CPU.

With the above configuration, any CPU
Even if the CPU malfunctions, the internal combustion engine can be stopped, so that the operation of the internal combustion engine can be prevented from being continued when the operation of some CPUs becomes abnormal.

The engine stop means provided for each CPU is a CPU
When the operation abnormality detecting means detects an abnormality in the operation of the other CPU, the internal combustion engine is caused to stop at least one of the operation of the ignition device that ignites the internal combustion engine and the supply of fuel to the internal combustion engine to stop the operation. It can be configured to stop.

In this specification, the term "CPU" is used in a broad sense including not only a microprocessor but also peripheral devices such as a memory, a timer, and an input / output device.

The function realizing means such as the CPU operation abnormality detecting means and the engine stopping means are realized by causing the CPU to execute a program having a predetermined algorithm. That is, providing the CPU with the predetermined function realizing means means that a program stored in the ROM for the CPU to execute has a configuration necessary for realizing the predetermined function.

[0015]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below, taking as an example a case where the present invention is applied to an internal combustion engine control device provided in a gas heat pump system.

(1) First Embodiment FIG. 1 shows a configuration of a first embodiment of the present invention.
In the figure, 1 is a commercial AC power supply, 2 and 3 are first and second transformers respectively for decreasing the output voltage of the AC power supply 1, 4 is an internal combustion engine driven by using gas as fuel, 5 is a fuel supply source, Reference numeral 6 denotes a fuel valve inserted in the middle of a fuel supply path for supplying fuel from the fuel supply source 5 to the internal combustion engine 4.
The illustrated fuel valve 6 is an electromagnetic valve that is opened and closed using a solenoid that operates when a voltage of the AC power supply 1 is applied as a drive source, performs an opening operation when a power supply voltage is applied, and removes the power supply voltage. It is configured to perform a closing operation when it is performed. Reference numeral 7 denotes an internal combustion engine control device, which controls the internal combustion engine 4 together with other control targets 8.
Here, the other control target 8 is, for example, a heat pump driven by the internal combustion engine 4. Reference numeral 9 denotes a pulser (pulse signal generator) including a rotor 9A attached to a rotating shaft (crankshaft or camshaft) of the internal combustion engine 4 and a stator 9B. The stator 9B of the pulser controls the rotation of the internal combustion engine. A pulse signal is generated when the rotation angle position of the shaft matches a predetermined position. In the illustrated example, the rotor 9A is made of a ferromagnetic material, and a
Are formed. Further, the stator 9B includes, for example, an iron core having a magnetic pole portion facing the outer periphery of the rotor 9A at its tip,
It consists of a pulsar coil wound around the iron core and a permanent magnet magnetically coupled to the iron core, and has different polarities when detecting the front edge and the rear edge in the rotational direction of the reluctor 9A1 on the outer periphery of the rotor 9A. Generate a pulse signal. These pulse signals are converted into CP signals by a waveform shaping circuit (not shown).
The signal is converted into a signal having a waveform recognizable by U and input to the CPU in the control device 7.

Reference numeral 10 denotes an ignition coil which constitutes an ignition device for an internal combustion engine together with an ignition circuit described later. In the illustrated example, the ignition coil 10 has a primary coil 10a and a secondary coil 10b, and one end of the primary coil 10a and a secondary coil 10b. Is connected through a diode 11 with the cathode facing the primary coil. The other end of the secondary coil 10b of the ignition coil is connected to a non-ground side terminal of a spark plug 12 attached to a cylinder of the internal combustion engine through a high-voltage cord.

The control device 7 includes a DC power supply 701 and a first
CPU 702 (CPU 1) and second CPU 703
(CPU2), a relay RY1 for turning on / off the energization of the fuel valve 6, and a drive circuit 7 for the relay RY1.
The ignition circuit 10 includes an ignition circuit 705 that forms an ignition device for an internal combustion engine together with the ignition coil 10, a relay RY2 that controls supply of an ignition power supply voltage to the ignition device, and a drive circuit 706 that drives the relay.

The DC power supply 701 includes a diode bridge full-wave rectifier Rec1 for rectifying a voltage obtained by stepping down the output voltage of the AC power supply 1 by the transformer 2, a smoothing capacitor C1 charged by the output of the rectifier, Rectifier Rec
Outputs a constant DC voltage with the output voltage of 1 as input 3
A voltage regulator Reg is provided between the output terminals of the regulator Reg to generate a voltage E1 for driving a CPU or the like, and a voltage E2 for driving a relay across the capacitor C1.

The relay RY1 has a normally open contact a1 inserted between one output terminal of the AC power supply 1 and one input terminal of the fuel valve 6, and an exciting coil L1.
A flywheel diode D1 is connected to both ends of 1.

One end of the exciting coil L1 is connected to the collector of an NPN transistor TR1 whose emitter is grounded.
The other end of the exciting coil L1 is connected to the non-ground terminal of the capacitor C1 of the DC power supply 701. The base of the transistor TR1 is connected to the port P1 of the second CPU 703 through the resistor R1.
Is connected to the non-ground side output terminal of the regulator Reg through the resistor R2. A resistor R3 is connected between the base and the emitter of the transistor TR1.
A drive circuit 703 for the relay RY1 is constituted by R1 and the resistors R1 to R3.

The relay RY2 has a normally open contact a2 inserted between one output terminal of the AC power supply 1 and one end of the primary coil 3a of the transformer 3, and an exciting coil L2.
A flywheel diode D is provided at both ends of the exciting coil L2.
2 is connected.

One end of the exciting coil L2 is connected to the collector of an NPN transistor TR2 whose emitter is grounded.
The other end of the exciting coil L2 is connected to the non-ground terminal of the capacitor C1 of the DC power supply 701. The base of the transistor TR2 is connected to the port P2 of the first CPU 702 through a resistor R4.
Is connected to the non-ground side output terminal of the regulator Reg through the resistor R5. A resistor R6 is connected between the base and the emitter of the transistor TR2.
A drive circuit 706 for the relay RY2 is constituted by R2 and the resistors R4 to R6.

The ignition circuit 705 includes a rectifier Rec2 for rectifying the output of the secondary coil 3b of the transformer 3, and a rectifier Re.
A smoothing capacitor C2 connected between the output terminals of c2
And an NPN transistor TR3 having a collector connected to one end of the primary coil of the ignition coil and an emitter grounded, and a voltage obtained across the capacitor C2 is applied between one end of the primary coil 10a of the ignition coil and the ground. Has been applied.

The base of the transistor TR3 is connected to the port P3 of the CPU 702 through the resistor R7.
02 port P3 is connected to a regulator R through a resistor R8.
EG is connected to the non-ground side output terminal. A resistor R9 is connected between the base and the emitter of the transistor TR3.
A Zener diode ZD1 and a diode D3 have their respective cathodes between the base and collector and between the collector and emitter of the transistor TR3.
3 is connected to the collector side. A transistor TR3, a resistor R9, a Zener diode ZD1,
A primary current control switch 704a that controls the primary current of the ignition coil 11 is constituted by the diode D3. The rectifier Rec2 and the capacitor C2 constitute an ignition power supply circuit.

The CPUs 702 and 703 have a communication port c
om, and the communication ports of both CPUs are connected to each other through a communication line 707. Each CPU 702, 703
Communicates with another CPU through the communication line 707 to detect at any time whether or not the operation of the other CPU is normal. In order for each CPU to detect an abnormality in the operation of the other CPU, a program executed by each CPU is provided with a process for realizing an operation abnormality detecting means for detecting an abnormality in the operation of the other CPU.

The input ports A1 and A2 of the CPU 702
, A pulse signal generated by the pulser 9 is input.
The CPU 702 calculates the rotation speed of the internal combustion engine 4 from the generation interval of the pulse signal given from the pulser 9, and determines the power supply start timing, which is the timing at which the primary current is supplied to the ignition coil 10 with respect to the calculated rotation speed. And the ignition timing of the internal combustion engine. The energization start timing and the ignition timing are calculated in the form of the time required for the engine to rotate from a predetermined specific rotation angle position (reference position) of the internal combustion engine to a rotation angle position corresponding to each timing. CPU
A reference numeral 702 detects the reference position from the pulse generated by the pulser 9, and starts measuring the calculated energization start timing and ignition timing when the reference position is detected. And
When the energization start timing is detected, the potential of the port P3 is set to L.
Level (low level) to H level (high level), and when the ignition timing is detected, the potential of the port P3 is changed to H level.
Change from level to L level.

The CPU 703 sends a signal from the port P3 to another control target 8 to control the other control target under a predetermined control condition.

In the illustrated control device, when each CPU is operating normally and the operation of the internal combustion engine is permitted, the potential of the port P2 of the CPU 702 is set to the H level, and the potential of the port P1 of the CPU 703 is changed to the H level. Is set to the H level.

When the potential of the port P1 of the CPU 703 is at the H level, the transistor TR1 is turned on, the relay RY1 is excited, and the contact a1 is closed. As a result, a voltage is applied to the fuel valve 6, so that the fuel valve 6 is opened, fuel is supplied from the fuel supply source 5 to the internal combustion engine 4, and the engine can be operated.

When the potential of the port P2 of the CPU 702 is H
When the level reaches the level, the transistor TR2 is turned on, the relay RY2 is excited, and the contact a2 is turned on. As a result, the transformer 3 and the rectifier Re
The ignition power supply voltage (DC voltage) is applied to the ignition circuit 705 through c2, and the ignition operation is enabled.

When the potential of the port P3 of the CPU 702 goes high while the ignition power supply voltage is being applied to the ignition circuit, the transistor TR3 is turned on, and the primary coil 10a and the transistor TR3 of the ignition coil 10 are turned on. A primary current flows between the collector and the emitter of the transistor. When the potential of the port P3 of the CPU 702 becomes L level (low level) at the ignition timing of the internal combustion engine, the transistor T
Since R3 is turned off, the primary current of the ignition coil 10 which has been flowing until then is cut off, and a high voltage for ignition is induced in the secondary coil 10b of the ignition coil 10. Since this high voltage is applied to the spark plug 12, a spark is generated at the spark plug and the engine is ignited.

That is, in the illustrated ignition device, the CPU 702
When the port P3 of the ignition coil goes high, the ignition coil 10
When the port P3 goes low, the primary current is interrupted and the ignition operation is performed.

The first CPU 702 has a second CPU
When the abnormality of the operation of 703 is detected, the potential of the port P2 is set to L level to turn off the transistor TR2,
The relay RY2 is de-energized. Thus, the contact a2 is opened, the ignition circuit 705 is disconnected from the ignition power source, and the ignition operation is stopped to stop the operation of the engine.

The second CPU 703 is a first CPU
When an abnormality in the operation of the port 702 is detected, the potential of the port P1 is set to L level to turn off the transistor TR1 and de-energize the relay RY1. As a result, the contact a1
Is opened, and the fuel valve 6 is closed to stop the operation of the engine.

As described above, each of the CPUs 702 and 703 has the engine stop means for stopping the internal combustion engine when the abnormality of the operation of the other CPU is detected.

In the control device shown in FIG.
FIGS. 2 and 3 show an example of an algorithm of a main part of a program executed by each of the CPUs 02 (CPU1) and 703 (CPU2), including a part for realizing a CPU operation abnormality detection unit and an engine stop unit. FIG. 2 is a flowchart showing an algorithm of a main part of a program executed by the CPU 1. When this algorithm is followed, first, in step 1, a check command is transmitted to the CPU 2 and a predetermined response signal is returned to the CPU 2. Request that Next, in step 2, it is determined whether or not a predetermined response signal has been returned from the CPU 2, and when a correct response has been received (when the operation of the CPU 2 is normal), the flow advances to step 3 to set the potential of the port P2 to the H level. . This turns on the transistor TR2 and turns on the relay RY.
The second contact a2 is turned on, and an ignition power supply voltage is applied to the ignition device. Next, proceeding to step 4, when the energization start time calculated by another routine is detected, the port P3
Is set to the H level, and a primary current flows through the primary coil of the ignition coil 10. Thereafter, as shown in step 5, when the ignition timing is detected, the potential of the port P3 is set to the L level to cut off the primary current of the ignition coil, thereby performing the ignition operation.

When it is determined in step 2 that there is no correct reply from the CPU 2 (when the operation of the CPU 2 is abnormal), the process proceeds to step 6, where the potential of the port P2 is set to the L level, thereby setting the relay RY2. As non-excitation, the ignition power is disconnected from the ignition device. Step 7
At this time, the conduction of the transistor TR3 is inhibited while keeping the potential of the port P3 at the L level.

FIG. 3 shows an algorithm of a main part (part relating to the present invention) of a program executed by the CPU 2. In the case of this algorithm, a check command is transmitted to the CPU 1 in step 1 and
1 is required to return a predetermined response signal.
Next, in step 2, it is determined whether or not a predetermined response signal has been returned from the CPU 1, and when a correct response has been received (when the operation of the CPU 1 is normal), the process proceeds to step 3, where the potential of the port P1 is set to the H level. . As a result, the transistor TR1 is turned on to excite the relay RY1, and the contact a1 is turned on to open the fuel valve 6. Next, in step 4, another control process performed when the CPU 1 is normal is performed.

When it is determined in step 2 that there is no correct reply from the CPU 1 (when the operation of the CPU 1 is abnormal), in step 5, the potential of the port P1 is set to the L level, and the relay RY1 is de-energized. The contact a1 is turned off. Thereby, the fuel valve 6 is closed, and the supply of fuel to the internal combustion engine is stopped. Further, as shown in step 6, other control processing performed when the CPU 1 is abnormal is performed.

In the example shown in FIG. 2, steps 1 and 2 constitute a CPU operation abnormality detecting means for detecting an abnormality in the operation of the CPU 2.
Engine stop means for stopping the operation of the ignition device and stopping the internal combustion engine 4 when it is detected that the operation of the engine 2 is abnormal.

Also, according to steps 1 and 2 in FIG.
CPU operation abnormality detection means for detecting an abnormality in the operation of U1 is constituted, and when the operation of CPU1 is detected to be abnormal in steps 5 and 6 in FIG. Engine stop means for stopping the engine 4 is configured.

(2) Second Embodiment FIG. 4 shows a configuration of a second embodiment of the present invention. In this example, the port P1 of the first CPU 702 is connected to the base of the transistor TR1 through the resistor R1. And the port P2 of the second CPU 703 is connected to the base of the transistor TR2 through the resistor R4. First
Communication port c of the CPU 702 and the second CPU 703
om are connected to each other by a communication line 707, and the port P3 of the first CPU 702 is connected to a transistor TR constituting a primary current control switch 705a of an ignition circuit.
3 is similar to the example shown in FIG.

In the control device shown in FIG.
When the CPU 703 is operating normally and the operation of the engine is permitted, the PU 702 sets the potential of the port P1 to the H level to excite the relay RY1, thereby opening the fuel valve 6 to open the fuel valve 6. Enable driving.

When the operation of the internal combustion engine is permitted, the second CPU 703 sets the potential of the port P2 to the H level to excite the relay RY2. As a result, the ignition power supply voltage is applied to the ignition device to enable the operation of the ignition device.

That is, in this example, the ignition device for igniting the internal combustion engine and the fuel valve 6 inserted in the middle of the fuel supply path to the internal combustion engine are controlled by one CPU 702, and the other CPU 703 controls the other The control of the control target 8 and the control of the supply of the ignition power supply voltage to the ignition device are performed.

The first CPU 702 is provided with a second CPU
When the abnormality of the operation of 703 is detected, the potential of the port P1 is set to L level to turn off the transistor TR1,
The relay RY1 is de-energized and its contact a1 is opened. Thus, the fuel valve 6 is closed, and the operation of the engine is stopped. Second
When detecting an abnormality in the operation of the first CPU 702, the CPU 703 sets the potential of the port P2 to the L level to turn off the transistor TR2 and de-energize the relay RY2. As a result, the contact a2 is opened, the application of the ignition power supply voltage to the ignition device is stopped, and the operation of the engine is stopped.

As described above, each of the CPUs 702 and 703 has the engine stopping means for stopping the internal combustion engine when the abnormality of the operation of the other CPU is detected.

The CPU 702 (C) of the control device shown in FIG.
FIGS. 5 and 6 are flowcharts showing the algorithm of the main part of the program executed by the PU1) and the CPU 703 (CPU2), respectively.

FIG. 5 shows the control device shown in FIG.
FIG. 5 is a flowchart showing an algorithm of a main part of a program executed by the CPU 1. When this algorithm is followed, first, in step 1, a check command is transmitted to the CPU 2 to request the CPU 2 to return a predetermined response signal. . Next, in step 2, the CPU
2 to determine whether a predetermined response signal has been returned,
When a correct reply is received (when the operation of the CPU 2 is normal), the routine proceeds to step 3, where the potential of the port P1 is set to the H level. As a result, the transistor TR1 is turned on, the contact a1 of the relay RY1 is turned on, and the fuel valve is opened to enable operation of the engine.

Next, proceeding to step 4, when the energization start time calculated by another routine is detected, the port P3
Is set to the H level, and a primary current flows through the primary coil of the ignition coil 10. Thereafter, as shown in step 5, when the ignition timing is detected, the potential of the port P3 is set to the L level to cut off the primary current of the ignition coil, thereby performing the ignition operation.

When it is determined in step 2 that there is no correct reply from the CPU 2 (when the operation of the CPU 2 is abnormal), the process proceeds to step 6 where the potential of the port P1 is set to the L level and the relay RY1 is de-energized. And Thus, the fuel valve 6 is closed to stop the operation of the engine. Further, the potential of the port P3 is held at the L level to inhibit the ignition operation.

FIG. 6 shows a second C control in the control device of FIG.
This shows the algorithm of the main part of the program executed by the PU 703 (CPU 2). In the case of this algorithm, a check command is transmitted to the CPU 1 in step 1 and a predetermined response signal is returned to the CPU 1. Request. Next, in step 2, the CP
It is determined whether or not a predetermined response signal has been returned from U1. When a correct response has been received (when the operation of the CPU 1 is normal), the routine proceeds to step 3, where the potential of the port P2 is set to the H level. As a result, the transistor TR2 is turned on to excite the relay RY2, and the contact a2 is turned on to apply the ignition power supply voltage to the ignition device. In step 4, another control process performed when the CPU 1 is normal is performed.

When it is determined in step 2 that there is no correct reply from the CPU 1 (when the operation of the CPU 1 is abnormal), the potential of the port P2 is set to the L level in step 5, and the relay RY2 is de-energized. The contact a2 is turned off. As a result, the ignition device is disconnected from the ignition power source, the ignition operation is stopped, and the engine is stopped. Further, as shown in step 6, other control processing performed when the CPU 1 is abnormal is performed.

In the example shown in FIG. 5, steps 1 and 2 constitute a CPU operation abnormality detecting means for detecting an abnormality in the operation of the CPU 2, and steps 6 and 7 form the CPU operation abnormality detecting means.
Engine stop means for stopping the supply of fuel to the internal combustion engine and stopping the internal combustion engine 4 when it is detected that the operation 2 is abnormal.

In the example shown in FIG. 6, the steps 1 and 2 constitute a CPU operation abnormality detecting means for detecting an abnormality in the operation of the CPU 1, and the step 5 in FIG.
Engine stop means for stopping the operation of the ignition device and stopping the internal combustion engine 4 when it is detected that the operation of the PU 1 is abnormal is configured.

(3) Third Embodiment FIG. 7 shows a configuration of a third embodiment of the present invention.
In this example, the port P1 of the second CPU 703 is connected to the base of the transistor TR1, and the port P2 is connected to the base of the transistor TR2. That is, in this example, the ignition device for igniting the internal combustion engine is controlled by one CPU 702, and the opening and closing of the fuel valve 6 inserted in the middle of the fuel supply path to the internal combustion engine is controlled by the other CPU 703. The supply of the power supply voltage is controlled.

In the control device shown in FIG.
When the operation of the CPU 703 is normal, the potential of the port P3 is set to the H level at the start of energization, and the port P3 is set at the ignition timing.
The ignition operation is performed by setting the potential of 3 to the L level. Also C
When the operation of the CPU 703 is abnormal, the PU 702 holds the potential of the port P3 at the L level, stops the ignition operation, and stops the operation of the engine.

When the operation of the CPU 702 is normal, the CPU 703 sets both the potential of the port P1 and the potential of the port P2 to the H level to excite the relays RY1 and RY2.
As a result, the fuel valve 6 is opened, the ignition power supply voltage is applied to the ignition circuit 705, and the engine can be operated. CPU7
03, when detecting that the operation of the CPU 702 is abnormal, both the potential of the port P1 and the potential of the port P2 are set to L level, and the relays RY1 and RY2 are de-energized. Thus, the fuel valve 6 is closed to shut off the fuel, the ignition circuit 705 is disconnected from the ignition power source, the ignition operation is stopped, and the engine is stopped.

As described above, in the control device shown in FIG. 7, both CPUs 702 and 703
Has an engine stopping means for stopping the internal combustion engine when an abnormality in the operation of the engine is detected.

CPUs 702 and 703 of the control device shown in FIG.
8 and 9 show the algorithm of the main part of the program executed by each of them.

FIG. 8 shows the control device shown in FIG.
FIG. 5 is a flowchart showing an algorithm of a main part of a program executed by the CPU 1. When this algorithm is followed, first, in step 1, a check command is transmitted to the CPU 2 to request the CPU 2 to return a predetermined response signal. . Next, in step 2, the CPU
2 to determine whether a predetermined response signal has been returned,
When a correct reply is received (when the operation of the CPU 2 is normal), the process proceeds to step 3, and the port P3
Is set to the H level to start energizing the primary current of the ignition coil. Thereafter, when the ignition timing is detected in step 4, the potential of the port P3 is set to the L level to cut off the primary current of the ignition coil and perform the ignition operation.

When it is determined in step 2 that there is no correct reply from the CPU 2 (when the operation of the CPU 2 is abnormal), the process proceeds to step 5 where the potential of the port P3 is held at the L level and the ignition operation is performed. To stop.

FIG. 9 shows the second C in the control device of FIG.
This shows the algorithm of the main part of the program executed by the PU 703 (CPU 2). In the case of this algorithm, a check command is transmitted to the CPU 1 in step 1 and a predetermined response signal is returned to the CPU 1. Request. Next, in step 2, the CP
It is determined whether or not a predetermined response signal has been returned from U1. When a correct response has been received (when the operation of the CPU 1 is normal), the routine proceeds to step 3, where the potential of the port P1 is set to the H level. This energizes the relay RY1 and opens the fuel valve 6. In step 4, the potential of the port P2 is set to the H level to excite the relay RY2 and apply the ignition power supply voltage to the ignition circuit. Next, in step 5, another control process performed when the CPU 1 is normal is performed.

When it is determined in step 2 that there is no correct reply from the CPU 1 (when the operation of the CPU 1 is abnormal), the potential of the port P1 is set to the L level in step 6, and the fuel valve 6 is closed. At 7, the potential of the port P2 is set to L level to disconnect the ignition device from the ignition power source, and the ignition operation is stopped. Thereafter, the process proceeds to step 8 to perform another control process performed when the CPU 1 is abnormal.

In the example shown in FIG. 8, the steps 1 and 2 constitute a CPU operation abnormality detecting means for detecting an abnormality of the operation of the CPU 2, and the step 5 detects that the operation of the CPU 2 is abnormal. Engine stop means for stopping the operation of the ignition device and stopping the internal combustion engine 4 at times is configured.

In the example shown in FIG. 9, steps 1 and 2 constitute a CPU operation abnormality detecting means for detecting an abnormality in the operation of the CPU 1, and steps 6 and 7 in FIG. Engine stop means for stopping the supply of fuel to the engine and stopping the operation of the ignition device to stop the internal combustion engine 4 when it is detected.

In each of the above examples, two CPUs are provided. However, the present invention is also applicable to a case where three or more CPUs are provided in the control device and at least one of them controls the internal combustion engine. Can be applied.

[0069]

As described above, according to the present invention, a plurality of CPUs are connected to each other via a communication line, and each of the CPU operation abnormality detecting means for detecting an abnormality in the operation of another CPU is provided.
U, and all the CPUs are provided with engine stop means for stopping the internal combustion engine when the operation abnormality of the other CPU is detected by the CPU operation abnormality detection means. However, the internal combustion engine can be stopped, and the operation of the internal combustion engine can be prevented from continuing when the operation of some CPUs becomes abnormal.

[Brief description of the drawings]

FIG. 1 is a configuration diagram showing a configuration of a first exemplary embodiment of the present invention.

FIG. 2 is a flowchart showing an algorithm of a main part of a program executed by a first CPU in the control device of FIG. 1;

FIG. 3 is a flowchart illustrating an algorithm of a main part of a program executed by a second CPU in the control device of FIG. 1;

FIG. 4 is a configuration diagram showing a configuration of a second exemplary embodiment of the present invention.

FIG. 5 is a flowchart illustrating an algorithm of a main part of a program executed by a first CPU in the control device of FIG. 4;

6 is a flowchart illustrating an algorithm of a main part of a program executed by a second CPU in the control device of FIG. 4;

FIG. 7 is a configuration diagram showing a configuration of a third exemplary embodiment of the present invention.

8 is a flowchart illustrating an algorithm of a main part of a program executed by a first CPU in the control device of FIG. 7;

9 is a flowchart illustrating an algorithm of a main part of a program executed by a second CPU in the control device of FIG. 7;

[Explanation of symbols]

1: AC power supply, 2, 3: Transformer, 4: Internal combustion engine, 6:
Fuel valve 7, 7 control device, 701 DC power supply unit, 702
First CPU, 703... Second CPU, 704, 706
... Relay drive circuit, 705 ... Ignition circuit, 707 ... Communication line, 8 ... Other controlled object, 9 ... Pulsar, 10 ... Ignition coil.

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme coat ゛ (Reference) F02D 43/00 301 F02D 43/00 301H F02P 11/00 F02P 11/00 B 11/04 302 11/04 302Z F-term (reference) 3G019 AB01 CA11 CB02 CB04 DC06 EA15 GA01 GA02 GA05 3G084 AA05 BA11 BA16 CA05 DA31 EA07 EB22 FA38 3G092 AA00 AB06 AC07 BA10 BB10 CB04 CB05 DE04S DG09 EA21 EA28 EB05 HA04B04 EB05 HC04 HAB NA07 NE07 PB03A PE04Z

Claims (2)

[Claims] 1. An internal combustion engine control device that controls an internal combustion engine together with another control object using a plurality of CPUs, wherein the plurality of CPUs are interconnected via a communication line,
CPU operation abnormality detection means for detecting an abnormality in the operation of another CPU is provided in each CPU, and engine stop for stopping the internal combustion engine when the abnormality in the operation of the other CPU is detected by the CPU operation abnormality detection means An internal combustion engine control device, wherein the means is provided in all CPUs. 2. An internal combustion engine control device that controls an internal combustion engine together with another control object by using a plurality of CPUs, wherein the plurality of CPUs are interconnected via a communication line,
Each CPU is provided with CPU operation abnormality detection means for detecting an abnormality in the operation of another CPU.
Stopping the internal combustion engine by stopping at least one of the operation of an ignition device that ignites the internal combustion engine and the supply of fuel to the internal combustion engine when an abnormality in the operation of the PU is detected An internal combustion engine control device characterized by comprising means.