JPS62265452A - Fail-safe controller for internal combustion engine controller - Google Patents

Abstract

PURPOSE:To enable a highly reliable fail-safe control by outputting an abnormality detection signal of a predetermined period in overlapping with an operation command signal, and cutting off the operation command signal of an operation element canon through detecting abnormality at the abnormality detection signal having become absent. CONSTITUTION:During an engine operation, a micro computer 8 outputs operation command signals a, b of an H level, putting 'on' the transistor Tr 17 in an abnormality detection circuit 11, and thus a condenser 16 is discharged. Also, signals c, d are respectively at an L level and H level, and a motor 5 is driven in one direction, and a throttle valve is operated in the direction of closing. Since a narrow abnormality detection signal e overlaps with the signal b at a predetermined period, the Tr 17 is left 'off' when the abnormality signal e ceases to overlap with the signal b. And then, the condenser 16 is charged, and the voltage at an F point surpasses a comparative voltage Vs, resulting in the abnormality detection signal e becoming H. Accordingly, signals c, d becomes respectively an L level and H level, and the throttle valve is operated in the direction of closing.

Description

【発明の詳細な説明】 〔産業上の利用分野〕 この発明は内燃機関制御装置のフェールセーフ制＠装置
に関するものである。DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a fail-safe system for an internal combustion engine control system.

〔従来の技術〕[Conventional technology]

従来の内燃機関制御装置においては、内燃機関の操作要
素をコンピュータによ多制御し、内燃機関の運転制御を
行っている。又、このような装置の７エールセー７制御
においては、コンピュータからの異常検出信号を異ｎ検
出回路により検出し、これに応じてフェールセーフ制御
を行っていた。In conventional internal combustion engine control devices, operating elements of the internal combustion engine are controlled by a computer to control the operation of the internal combustion engine. In addition, in the control of such a device, an abnormality detection signal from a computer is detected by an abnormality detection circuit, and fail-safe control is performed in response to this detection.

〔発明が解決しようとする問題点〕[Problem that the invention seeks to solve]

しかるに、上記従来装置では、操作要素への操作指令信
号と異常検出４ｇ号とは別々に出力されており、異常検
出信号が異常であっても操作指令信号に異常はない場合
やその逆の場合があり、必ずしも正確なフェールセーフ
制御が行われないという問題点があった。However, in the conventional device described above, the operation command signal to the operation element and the abnormality detection No. 4g are output separately, and even if the abnormality detection signal is abnormal, there is no abnormality in the operation command signal, or vice versa. However, there was a problem that accurate fail-safe control was not necessarily performed.

この発明は上記した従来の問題点を解決するために成さ
れたものであり、正確なフェールセーフ制御全行うこと
ができる内燃機関側＠Ｊ装置のフェールで一７制御装置
全得ること全目的とする。This invention was made in order to solve the above-mentioned conventional problems, and the overall purpose is to obtain all 17 control devices by failing the J device on the internal combustion engine side, which is capable of performing accurate fail-safe control. do.

〔問題点を解決するための手段〕[Means for solving problems]

この発明に係る！７３燃機関制御装置のフ二一ルセ−フ
制御装置は、コンピュータによシ操作指令信号に重畳し
て操作要素に対して不感信号となる異常検出信号を出力
するとともに、この異常検出信号が絶え之ことによシ異
常を検出する異常検出回路と、この異常検出回路の出力
を受けて操作指令信号を遮断する異常切換回路を設け、
かつ異常時に操作要素を安全側に操作するようにしたも
のである。Regarding this invention! The safety control device of the 73 fuel engine control device outputs an abnormality detection signal that is superimposed on the engine operation command signal to the computer and serves as an insensitivity signal to the operating element. In particular, an abnormality detection circuit that detects an abnormality and an abnormality switching circuit that receives the output of this abnormality detection circuit and cuts off the operation command signal are provided.
In addition, the operating elements are operated to the safe side in the event of an abnormality.

〔作　用〕[For production]

この発明においては、コンピュータから操作指令信号に
重畳して異常検出信号を出力して２り、操作要素を直接
操作する信号に異常検出機能を持た一＋！：たことによ
り、正確なフェールセール制御を行うことができる。In this invention, the computer outputs an abnormality detection signal superimposed on the operation command signal, and the signal for directly operating the operation element has an abnormality detection function. :Accurate fail-sail control can be performed.

〔実施例〕〔Example〕

以下、この発明の実施例を図面とともに説明する。第１
図において、１は内燃機関の吸気管、２は吸気管ｌに設
けられ、その吸気量を制御するスロットル弁、３はスロ
ットル弁２ｔ−駆動するプランジャ、４はプランジャ３
の位置を検出するプランジャポジションセンナ、５はプ
ランジャ３百−駆動スルモータ、６はプランジャポジシ
ョンセンサ４の出力を入力されるとともにモータ５　ｆ
　ｋｌｉ御する制御ユニットである。Embodiments of the present invention will be described below with reference to the drawings. 1st
In the figure, 1 is an intake pipe of an internal combustion engine, 2 is a throttle valve provided in the intake pipe l and controls the amount of intake air, 3 is a plunger that drives the throttle valve 2t, and 4 is a plunger 3
A plunger position sensor 5 detects the position of the plunger 3, a motor 5 for driving the plunger 3, and a motor 5 which receives the output of the plunger position sensor 4.
This is a control unit that controls the kli.

上記構成において、制御ユニット６はプランジャポジシ
ョンセンサ４の出方を加えられてモータ５を駆動するこ
とによりスロットル弁２を駆動し、アイドル的に内燃機
関の速度を制御する。In the above configuration, the control unit 6 drives the throttle valve 2 by driving the motor 5 in response to the output of the plunger position sensor 4, thereby controlling the speed of the internal combustion engine in an idling manner.

又、第２図は制御ユニット６の内部構成を示し、７はプ
ランジャポジションセンサ４の出力を入力されてＡ／Ｄ
　ｆ換するＡ／Ｄ　ｉ換器、８はＡ、／Ｄ変換器７の出
力を入力されるマイクロコンピュータ、９．１０はマイ
クロコンピュータ８の出力線。Further, FIG. 2 shows the internal configuration of the control unit 6, and 7 receives the output of the plunger position sensor 4 and is connected to the A/D.
8 is a microcomputer to which the output of the A/D converter 7 is input; 9.10 is an output line of the microcomputer 8;

１１は出力線１０の信号すを加えられ、異常検出信号ｅ
ｆ比出力る異常検出回路、１２け出力線９の信号ａと異
常検出信号ｅを入力されるノア回路、１３は信号すと信
号ｅを加えられるオア回路でるる。11 is added with the signal of the output line 10, and the abnormality detection signal e
An abnormality detection circuit which outputs a ratio f, a NOR circuit which receives the signal a of the 12-digit output line 9 and the abnormality detection signal e, and 13 an OR circuit to which the signal e is added.

第３図は異常検出回路１１の回路構成を示し、１４は比
較器、１５．１８は抵抗、１６はコンデンサ、１７はト
ランジスタである。FIG. 3 shows the circuit configuration of the abnormality detection circuit 11, in which 14 is a comparator, 15.18 is a resistor, 16 is a capacitor, and 17 is a transistor.

第２図および第３図に示し７た構成の動作を第４図のタ
イミングチャート全参照して説明する。まず、マイクロ
コンピュータ８は操作指令信号ａ。The operation of the configuration shown in FIGS. 2 and 3 will be explained with full reference to the timing chart in FIG. 4. First, the microcomputer 8 receives an operation command signal a.

ｂｔ−Ｈで出力し、トランジスタ１７がオンしてコンデ
ンサ１６は放電状態にあり、信号ｅはＬ（！：なり、信
号ＣはＬ１伯号ｄはＨとなってモータ５には実線の矢印
のように電流が流れ、プランジャ３を介してスロットル
弁２は閉方向に操作される。The output is bt-H, the transistor 17 is turned on, the capacitor 16 is in a discharge state, the signal e becomes L (!:), the signal C becomes L1, the signal d becomes H, and the motor 5 receives the signal indicated by the solid arrow. A current flows, and the throttle valve 2 is operated in the closing direction via the plunger 3.

ここで、信号すがＬとなり、トランジスタ１７がオフと
なってコンデンサ１６がやや充電されるが信号すには幅
の狭い異常検出信号か所定周期で重畳され、この除ＶＣ
はコンデンサ１６が放電されてｆ点の電圧は上昇せず、
信号ｅはＬの１１である。Here, the signal becomes L, the transistor 17 is turned off, and the capacitor 16 is slightly charged.
The capacitor 16 is discharged and the voltage at point f does not rise,
The signal e is L11.

このため、信号ｃ、ｄが共にＬでモータ５は停止状態で
ある。次に、信号ａがＬとなり、信号ＣがＨ１信号ｄが
Ｌとなってモータ５には点線の矢印のように電流が流れ
、スロットル弁２は開方向に操作される。ここで、異常
検出信号が信号すに重畳されなくなるとトランジスタ１
７はオフのままとなジ、コンデンサ１６は充電されてｆ
点のｔｆｆが比較電圧Ｖ３ｔ−超え、異常検出信号ｅが
Ｈとなる。この次め、信号ＣがＬ、信号ｄがＨとｌ）、
スロットル弁２が閉方向即ち速度が低下する安全側に操
作される。Therefore, both signals c and d are L, and the motor 5 is in a stopped state. Next, the signal a becomes L, the signal C becomes H1, and the signal d becomes L, a current flows through the motor 5 as indicated by a dotted arrow, and the throttle valve 2 is operated in the opening direction. Here, when the abnormality detection signal is no longer superimposed on the signal, the transistor 1
7 remains off, capacitor 16 is charged and f
The point tff exceeds the comparison voltage V3t-, and the abnormality detection signal e becomes H. Next, signal C is L, signal d is H and l),
The throttle valve 2 is operated in the closing direction, that is, on the safe side where the speed decreases.

尚、上記実施例では操作要素としてスロットル弁２の例
を示したが、他の操作要素にも適用できる。Incidentally, in the above embodiment, the throttle valve 2 was used as an example of the operating element, but the present invention can also be applied to other operating elements.

〔発明の効果〕〔Effect of the invention〕

以上のようにこの発明によれば、コンピュータから出力
される操作要素への操作指令信号に異常検出信号を重畳
しており、操作要素を直接操作する信号に異常検出機能
を持ｆｃぜたことにより、正確なフエールセーフ制御ヲ
行うことができる。又、コンピュータの出力ボートを簡
単にすることができる。As described above, according to the present invention, the abnormality detection signal is superimposed on the operation command signal to the operating element output from the computer, and the abnormality detection function is added to the signal for directly operating the operating element. , accurate fail-safe control can be performed. Also, the computer output port can be simplified.

【図面の簡単な説明】[Brief explanation of drawings]

第１図はこの発明に係る内燃機関制御装置の幻′成図、
第２図（２この発明に係る匍ｊ御ユニットの桧′成図、
第３図はこの発Ｅ！ＡＶＣ係る異常検出回路の回略図、
第４図はこの発明に係る制御ユニットのタイミングチャ
ートである。 ２・・・スロットル弁、４・・・プランジャポジション
センサ、５・・・モータ、６・・・制御ユニット、８・
・・マイクロコンピュータ、ｌｌ・・・異常検出回路、
１２・・・ノア回路、１３・・・オア回路。 尚、図中同一符号は同−又は相当部分を示す。FIG. 1 is a phantom diagram of an internal combustion engine control device according to the present invention.
FIG.
Figure 3 shows this E! A schematic diagram of an abnormality detection circuit related to AVC,
FIG. 4 is a timing chart of the control unit according to the present invention. 2... Throttle valve, 4... Plunger position sensor, 5... Motor, 6... Control unit, 8...
...Microcomputer, ll...Abnormality detection circuit,
12...NOR circuit, 13...OR circuit. Note that the same reference numerals in the figures indicate the same or corresponding parts.

Claims (1)

【特許請求の範囲】[Claims] （１）内燃機関に設けられた操作要素に操作指令信号を
出力し機関の運転を制御するとともに、この操作指令信
号に重畳して前記操作要素に対して不感信号となる所定
周期の異常検出信号を出力するコンピユータと、異常検
出信号を重畳した操作指令信号を受け、異常検出信号が
所定時間絶えたことにより異常を検出する異常検出回路
と、異常検出回路の出力を受けて操作要素への操作指令
信号を遮断する異常切換回路を備え、かつ操作指令信号
が遮断された際に操作要素を安全側に操作するようにし
たことを特徴とする内燃機関制御装置のフエールセーフ
制御装置。(1) An operation command signal is output to an operating element provided in the internal combustion engine to control the operation of the engine, and an abnormality detection signal of a predetermined period is superimposed on this operation command signal and serves as an insensitive signal for the operating element. an abnormality detection circuit that receives an operation command signal superimposed with an abnormality detection signal and detects an abnormality when the abnormality detection signal disappears for a predetermined period of time; and an operation element that receives the output of the abnormality detection circuit. 1. A fail-safe control device for an internal combustion engine control device, comprising an abnormality switching circuit for cutting off a command signal, and operating an operating element to a safe side when the operation command signal is cut off.