JPS639678A - Trouble transmission device of internal combustion engine controller - Google Patents

Abstract

PURPOSE:To avoid the need of a trouble signal transmission means for exclusive use, etc. by sending a trouble signal into a fundamental control means by utilizing a transmission means between the fundamental control means and a knocking control means when a trouble is generated inside the knocking control means or between said means and an ignition means. CONSTITUTION:A fundamental control means 10 for calculating the fundamental ignition time and fuel injection control value of an internal combustion engine is installed, and a knocking control means 12 for delaying the ignition timing by a prescribed quantity in the case when knocking is generated by the input of the fundamental ignition timing signal is installed separately from the fundamental control means 10, and an ignition means 14 is controlled by the output signal of the control means 12. The fundamental control means 10 and the knocking control means 12 are connected through a signal transmission means 16. In this case, a trouble signal output means 18 is installed in the knocking control means 12, and a trouble signal is sent into the fundamental control means 10 through a signal transmission means 14 according to the trouble generated inside the knocking control means 12 and between said means 12 and the ignition means 14.

Description

Detailed Description of the Invention (Industrial Field of Application) The present invention relates to a fault transmission device for an internal combustion engine control device, and more specifically, the present invention relates to a fault transmission device for an internal combustion engine control device, and more specifically, a failure transmission device that is separate from a basic control unit that calculates and controls basic ignition timing and fuel injection. In a control system for an internal combustion engine equipped with a knocking control unit, a fault transmission device that transmits a fault occurring in the knocking control unit or the like to a basic control unit is used.

(Prior art) It is well known that knocking control is performed in a control device for an internal combustion engine.
The technique described in Japanese Patent No. 2706 can be mentioned. In this conventional example, the ignition timing is determined in the delay control circuit 6 according to the frequency of occurrence of knocking.

(Problems to be Solved by the Invention) Although it is not necessarily clear from this conventional example, when configuring such a knocking control unit, it has also been conventionally done to configure it separately from the basic control unit. In that case, if a failure occurs within the knocking control unit or in a signal transmission means such as a cable connecting it to a subsequent ignition device, it may be necessary to stop fuel injection to protect the exhaust system. In this case, if the knocking control unit is configured separately from the basic control unit, it is usually necessary to provide dedicated fault signal transmission means from the knocking control unit to the basic control unit. In addition, in order to ensure the transmission function, it is necessary to further provide an abnormality monitoring circuit for the transmission means. There was an inconvenience that reduced reliability.

Furthermore, if a failure occurs in the knocking control unit, such as a failure of the knock sensor, the backup amplifier system is usually used as a replacement, but if such a failure is left untreated for a long time, there may be inconveniences such as decreased performance or increased fuel consumption. Since this is likely to occur, it is desirable to have a fault diagnosis memory circuit that can store the fault condition and issue a warning immediately or at a later periodic maintenance inspection. However, in the case of a separate configuration, providing such a memory circuit also in the knocking control unit is similarly inconvenient in terms of cost and reliability.

Therefore, an object of the present invention is to eliminate the above-mentioned drawbacks of the prior art, and to provide an internal combustion engine control device in which a basic control unit and a knocking control unit are configured separately, by connecting the two to transmit a basic ignition timing signal. To provide a failure transmission device for an internal combustion engine control device, which transmits a failure signal from a knocking control unit when a failure occurs by using a transmission means that makes it unnecessary to provide a dedicated failure signal transmission signal to the knocking control unit. It is in.

Furthermore, the fault signal is sent to the basic control unit via the basic ignition timing signal transmission means and stored in its fault diagnosis memory circuit, thereby eliminating the need to provide a fault diagnosis memory circuit in the knocking control unit. An object of the present invention is to provide a fault transmission device for an internal combustion engine control device.

(Means and operations for solving the problems) In order to achieve the above object, the present invention provides a basic control means lO1 for calculating and controlling basic ignition timing and fuel injection of an internal combustion engine, as shown in FIG. knocking control means 12 which is configured separately from the control means and inputs a basic ignition timing signal outputted therefrom to retard the ignition timing by a predetermined amount when knocking occurs;
An internal combustion engine control comprising an ignition means 14 connected to the knocking control means and inputting its output to ignite the air-fuel mixture in the internal combustion engine cylinder, and a means transmission means 16 connecting the basic control means and the knocking control means. In the device, a failure signal is included in the knocking control means and sends a failure signal to the basic control means via the signal transmission means in response to a failure occurring within the knocking control means and between it and the ignition means. The configuration is such that an output means 18 is provided.

(Example) Hereinafter, the present invention will be described in detail with reference to the accompanying drawings.

FIG. 2 shows the overall configuration of the device according to the present invention. In the figure, reference numeral 10 indicates a basic control unit as the basic control means. The unit 10 includes a basic ignition timing calculation device 2
0, an output circuit 22, a failure signal monitoring circuit 24, a failure mode discrimination circuit 26, a storage means 28, a display device 30, and a fuel injection control device 32, most of which are made up of a microcomputer.

A crank angle sensor 36 disposed near the rotating part of the internal combustion engine 34 and a negative pressure sensor 38 disposed in the air introduction passage near the throttle valve are connected to the basic ignition timing calculation device 20, and a reference crank angle signal is output from the engine. Input the rotation speed signal and negative pressure signal, calculate the basic ignition timing using a known method, and connect the signal line 4.
0 to the output circuit 22.

The output circuit 22 is composed of resistors 22a, 22b and a transistor 22c. The collector potential of the transistor 22c is connected to a signal line 44 via a connection point 42. The signal line 44 is connected to the signal transmission means 16 and also to the fault signal monitoring circuit 24 . Note that a zener wire is connected between the signal line 44 and the base terminal of the transistor 22C.
A diode 22d is inserted.

The failure signal monitoring circuit 24 connects the signal line 44 to a resistor 24a.
, 24b, the collector terminal of which is connected to the voltage source via a resistor 24d,
Exclusive OR gate 24 via connection point 24e
It is read directly to one input terminal of f. The other input terminal of the gate 24f is connected to the signal line 40 via a connection point 46, and its output terminal is connected to the failure mode determination circuit 26.

The failure mode determination circuit 26 includes a counter 26a and a monostable multipipe rake 26b.

The input terminal of the counter 26a is connected to the output terminal of the gate 24f, and its reset terminal is connected to the output terminal of the multi-by-break 26b. The input terminal of the multi-high break 26b is connected to the signal line 4 via a connection point 48.
Connected to 0. The signal of the counter 26a is stored in the storage means 2.
8 and the fuel injection control device 32. Although the information is actually inputted via the CPU, input/output interface, etc., it is shown as being directly inputted for convenience of illustration.

The storage means 28 is constituted by a RAM or the like, and the counter 26
It inputs the output of a, and functions as the above-mentioned fault diagnosis storage circuit. The failure mode stored in the storage means is displayed on the display device 30 as needed.

The fuel injection control device 32 operates in synchronization with the basic ignition timing calculation device, calculates a fuel injection control value by inputting the outputs of the crank angle sensor 36 and the negative pressure sensor 38, and includes an injection valve and its drive circuit. Output to the fuel injection device 50. or,
The fuel injection control device stops fuel injection as described later in accordance with the output value of the counter 26a.

The above-described signal transmission means 16 is provided at the next stage of the basic control unit 10, and connects the basic control unit 10 to the knocking control unit 12, which is the above-mentioned knocking control means. In this specification, the term "signal transmission means" is used to mean connectors, cables, conductors of printed circuit boards, and circuit elements made of electrical conductors.

The knocking control unit 12 includes an input circuit 52, a knocking calculation device 54, an output circuit 56, an abnormality detection circuit 58,
It is comprised of bank amplifier circuits 17 & 60 and a failure signal output circuit 18 which is the above-mentioned failure signal output means.

The input circuit 52 is connected to the signal transmission means 16 via a signal line 62, and is an input switch circuit including a pull-up resistor 52a, resistors 52b, 52c, 52d, 52e, 52f, transistors 52g, 52h, and a diode 52i. The output thereof is connected to the knocking calculation device 54 via a signal line 64.

The knocking calculation device 54 is connected to the basic control unit 10.
It is composed of a microcomputer separate from the microcomputer that mainly constitutes the internal combustion engine 34, and inputs the basic ignition timing signal sent by the basic control unit 10 via the input circuit 52 and the signal transmission means 16.
No. 7
Detect the king. When knocking is detected, the basic ignition timing signal is appropriately retarded, and when knocking is not detected, the basic ignition timing signal is directly sent to the next stage via the output circuit 56. Further, the knocking calculation device 54 is
It includes an abnormality judgment circuit and storage means (both not shown) for monitoring failure of the device.

The output circuit 56 includes resistors 56a, 56b, and a transistor 5.
6c and a Zener diode 56d. The base terminal of the transistor 56c is connected to the output terminal of the knocking calculation device via the resistor 56a and the changeover switch 68, and the collector terminal thereof is connected to the signal line 70.
Output to the outside of the unit via.

The abnormality detection circuit 58 includes resistors 58a and 58b.

58c and a transistor 58d.

The base terminal of the transistor 58d is connected to the signal line 70 via the resistor 58a and the connection point 72, and the collector terminal is connected to the knocking calculation device 54 via the signal line 74.

The backup circuit 60 is an alternative means when the knocking calculation device 54 or the like is abnormal, and is connected to the input circuit 52 via the connection point 76.
It is also connected to the output terminal of the output circuit 56 via the changeover switch 68.

The failure signal output circuit 18 includes resistors 18a and 18b and a transistor 18c. The base terminal of the transistor 18c is connected to the knocking calculation device 54 through the resistor 18a and the signal line 78, and the collector terminal thereof is connected to the signal line 62 of the input circuit 52 through the connection point 80.
connected to.

A signal transmission means 82, which is similar to the signal transmission means 16, is connected via a signal line 70 to the output end of the knocking control unit 12, and on the other hand to the ignition device 14, which is the ignition means.

The ignition device 14 includes an igniter circuit and the like, and ignites the cylinder air-fuel mixture via a spark plug (not shown).

Next, the operation of this apparatus will be explained with reference to FIG. 2 and FIGS. 3 and 4.

The basic ignition timing calculating device 20 calculates the basic ignition timing and sends a pulse signal (FIG. 3a) to the output circuit 22. The level of the signal is inverted in the output circuit (b in the figure), and sent to the knocking control unit 12 through the signal transmission means 16, and then sent to the knocking calculation device 5 through its input circuit 52.
4 is input. The knocking calculation device 54 corrects the basic ignition timing signal depending on the presence or absence of knocking, or outputs it as an energization signal without correction, and the output signal is sent to the ignition device 14 via the output circuit 56 and signal transmission means 82. The air-fuel mixture is ignited (C in the same figure). If the device is normal, this operation is repeated.

On the other hand, in the basic control unit 10, the potential of the output end of the output circuit 22 and the signal transmission means 16 outside the unit connected thereto is connected to the fault signal monitoring circuit 2 via the signal line 44.
The input pulse is also input to transistor 24.
After the level is inverted again by C (d in the figure), it is input to one input terminal of the exclusive OR gate 24f. A basic ignition timing signal (a in the figure) is inputted to the other input terminal of the gate 24f via a connection point 46.

When the device is operating normally, the output of the gate 24f is at the "L" level because the pulses from both sides match (see e in the figure), but if the signal transmission means 16 is open, shorted to ground, or unstable When such a failure occurs, the input pulse is fixed at the "L" level, and as a result, the gate output outputs one pulse per one period of change in the basic ignition timing signal. The gate output is input to the counter 26a of the failure mode discrimination circuit 26. The counter 26a receives the basic ignition timing signal via the multi-by-break 26b at its reset terminal and is reset every cycle at an appropriate time (
(f) in the figure, the number of output pulses of the gate 24f is counted every cycle and sent to the storage means 28 and the fuel injection control device 32. When the counter value is 1, the storage means 28 assumes that the signal transmission means 16 has failed, turns on the flag as the first failure mode, stores the data as failure diagnosis information, and displays the data as appropriate on the display device. 30 to give a warning. Further, the fuel injection control device 32 stops fuel injection to protect the exhaust system. In this way, failures in the signal transmission means 16 are detected and dealt with by the basic control unit 10 on the upstream side.

Next, to explain failure detection such as a ground short circuit in the signal transmission means 82 of the same type, the signal transmission means 82 as shown in FIG.
The potential No. 2 turns on/off the transistor 58d of the abnormality detection circuit via the signal line 70 and the connection point 72, and its collector potential is input into the knocking calculation device 54 via the signal line 74. . Therefore, an internal abnormality judgment circuit (not shown) compares the potential with the collector potential of the transistor 56c of the output circuit 56, and if the asynchronous state exceeds a predetermined dead zone, it can be determined that the signal transmission means 82 has failed. 2 failure mode, the number of pulses to be generated is set to 2, and is stored in a storage means (not shown) in the arithmetic unit 54.

In addition, when the output level of the knock sensor 66 drops below a predetermined value and this state continues for a predetermined number of ignitions, the abnormality judgment circuit detects the third failure mode (the number of pulses to be generated is 3). ) and make him remember it. Furthermore, even when the backup circuit 60 is not operating, the abnormality judgment circuit monitors whether the retard amount is within a predetermined tolerance range, and if it is outside the tolerance range, the failure mode (occurrence) of Section 4 is determined. Promise the number of pulses to be used (4) and have it memorized. In addition, abnormalities in the signal system of the output circuit 56 are also monitored, and the failure mode and number of pulses to be generated are determined accordingly. If you rearrange this, it will look like this:

Failure mode Number of pulses Failure location l 1 Signal transmission means 16 2 2 Signal transmission means 82 3 3 Knock sensor 66 4 4 Backup circuit 605 5
Output circuit 56, etc. Next, except for the case of failure mode 1, the case of transmitting the failure mode stored in the knocking calculation device 54 to the basic control unit 10 will be explained.
As shown in the figure, the knocking calculation device 54 includes an input circuit 5
When the basic ignition timing pulse (FIG. 3 and FIG. 4b) input to the circuit 2 is at the "H" level, the number of pulses corresponding to the failure mode is sent to the failure signal output circuit 18 via the signal line 78, The transistor 18C is turned on and off. The collector potential of this transistor 18C is the connection point 80,
Since it is input to the fault signal monitoring circuit 24 via the signal line 6.2, the signal transmission means 16 and the signal line 44, the gate 24
f outputs the corresponding number of pulses (FIG. 4e), and the number of output pulses is counted by the counter 26a. still,
The output section of the failure mode pulse is determined by the ``H'' of the ignition signal, which is determined by the detected values of the crank angle sensor 36 and the negative pressure sensor 38, so that all pulse trains can be sent even if the maximum number of pulses is generated.
゛The level section is divided and set as appropriate, and a transmission prohibited section is provided for a predetermined period of time before and after the level section to avoid erroneous transmission. or,
The knocking calculation device 54 does not accept the energization start signal inputted as the basic ignition timing pulse when the failure mode pulse is output, thereby preventing malfunction of the ignition device 14.

FIG. 5 is a flow chart showing the failure signal reception procedure on the basic control unit side. After resetting the counter 26a and counting pulses, it is determined whether the number of pulses is greater than 0 (steps 84 and 86). .88). If there is no pulse, it is assumed that there is no failure, but if the number of pulses is 1, it is determined that there is a failure in the signal transmission means 16, the failure mode flag is turned on and stored, and fuel injection is stopped and a warning is displayed ( Step 9'0, 92, 94.96). or,
If the number of pulses is "2", the flag for the failure mode is turned on and stored, and if the signal transmission means 82 fails, the fuel injection is similarly stopped (steps 98 and 100).
．． 94), and in any case display and warn (steps 96 and 102). The storage means 28 of the basic control unit includes:
As mentioned above, it also serves as the fault diagnosis storage circuit for the knocking control unit.

FIG. 6 shows a second embodiment of the present invention, showing another configuration example 52', 18° of the input circuit and fault signal output circuit of the knocking control unit.

Since there is no difference in operation from the first embodiment, a description thereof will be omitted.

FIG. 7 shows a third embodiment of the present invention, showing yet another input circuit example 52''. The fault signal output circuit is comprised of an electronic switch 104.

FIG. 8 shows a fourth embodiment of the present invention, in which a reception confirmation pulse is transmitted from the basic control unit 10 within a data reception confirmation period after a predetermined period of time has elapsed from the energization start time of the basic ignition timing signal. The knocking arithmetic unit 54 can be configured to receive the pulse and confirm the transmission of the failure mode, and to send the data again if the pulse is not returned. Note that the knocking calculation device 54 also operates within this section.
is constructed so as not to receive the energization start signal.

Through the above embodiments, data communication has been explained limited to failure information, but it is not limited thereto, and may be used to send and receive control data, operating status data, and the like.

(Effects of the Invention) The present invention provides a fault signal in an internal combustion engine control device in which a knocking control means is configured separately from a basic control means, by using a signal transmission means that connects the two and transmits a basic ignition timing signal. Since the knocking control means is provided with a failure signal output means for transmitting to the basic control means, failure information can be transmitted from the knocking control means to the basic control means without providing a dedicated failure signal transmission means and its abnormality monitoring circuit. This has the advantage of simplifying the device configuration, improving reliability, and reducing costs.

Furthermore, since the knocking control means is constructed so that the failure information is transmitted to the basic control means and stored in its storage means, the knocking control means itself no longer needs to be provided with a storage circuit for failure diagnosis, and the circuit configuration can also be changed. The advantages include simplification, improved reliability, and reduced costs.

[Brief explanation of drawings]

Figure 1 is a diagram corresponding to the claims of the present invention, Figure 2 is a block diagram showing the circuit configuration of the device according to the present invention, Figures 3 and 4 are output waveform diagrams of each circuit, and Figure 5 is the basic diagram. Flowchart showing the failure signal reception procedure of the control unit, FIG. 6 is a circuit diagram showing the second embodiment of the present invention, FIG. 7 is a circuit diagram showing the third embodiment of the present invention, and FIG. FIG. 7 is an output waveform diagram showing a fourth embodiment of the present invention. 10... Basic control means (basic control unit), 12.
・・Knocking control means (knocking control unit),
14... Ignition means (ignition device), 16... Signal transmission means, 18... Failure signal output means (failure signal output circuit), 20... Basic ignition timing calculation device, 28... Storage means , 32...Fuel injection device, 54...Knocking calculation device Fig. 4f-L--"L--Knee-"-1 Fig. 6 Fig. 7

Claims (3)

[Claims] (1) a. A basic control means for calculating and controlling the basic ignition timing and fuel injection of the internal combustion engine; b. A basic control means that is configured separately from the basic control means and generates knocking by inputting the basic ignition timing signal outputted by the basic control means. knocking control means that sometimes retards the ignition timing by a predetermined amount; c. ignition means connected to the knocking control means and inputting its output to ignite the air-fuel mixture in the internal combustion engine cylinder; and d. the basic control means. and a signal transmission means for connecting the knocking control means and the knocking control means, e. A fault transmission device for an internal combustion engine control device, comprising: fault signal output means for transmitting a fault signal to the basic control means via the signal transmission means. (2) A failure transmission device for an internal combustion engine control device according to claim 1, wherein the failure signal output means comprises a pulse output means, and the number of output pulses is varied depending on the failure mode. . (3) The basic control means includes a storage means, and inputs the pulse and stores it in the storage means, and also stops fuel injection according to a failure mode. Fault transmission device for the internal combustion engine control device as described.