JPS5819532A

JPS5819532A - Method and device for detecting misfire of reciprocating engine

Info

Publication number: JPS5819532A
Application number: JP11891681A
Authority: JP
Inventors: Shigeru Miyata; 繁宮田
Original assignee: NGK Spark Plug Co Ltd; Nippon Tokushu Togyo KK
Current assignee: Nippon Tokushu Togyo KK; Niterra Co Ltd
Priority date: 1981-07-28
Filing date: 1981-07-28
Publication date: 1983-02-04

Abstract

PURPOSE:To perform the detection of the misfire directly and quickly and to perform the detection in a broad checking range accurately, by judging the misfire when the rotating speed of a crank shaft is not accelerated in an expansion stroke. CONSTITUTION:An electromagnetic pickup 3 detects the rotating speed of the crankshaft 2 of the reciprocating engine 1. A pulse generator 4 converts the period of the set angle of the crankshaft 2 detected by the electromagnetic pickup into a pulse width. An expansion stroke dislaying pulse generator 5 generates pulse which displays the entire expansion stroke of the cylinder, wherein the misfire is detected, in the reciprocating engine or a specified part of the stroke. In this case, output pulses from the pulse generator 4 is distinguished into the pulse which is located within the width of the output pulse from the expansion stroke display pulse generator 5 and the pulse which is located outside said pulse width, and the results are outputted. A pulse width measuring circuit 7 measures the width of the output pulse from the pulse generator 4. A misfire judging circuit 9 compares the pulse width before the expansion stroke and the pulse width after the expansion stroke. When the differnce is lower than a preset value, a high level output is generated and a display 11 is operated.

Description

【発明の詳細な説明】本発明は往復機関で着火ミスによる失火が生じたとき該
失火を検出する方法および該方法に用いる失火検出装置
に関する。DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for detecting a misfire caused by ignition error in a reciprocating engine, and a misfire detection device used in the method.

内燃機関における失火の検出には排気温度を検出するも
の、排ガス分析によるもの、イオン電流の検出によるも
の等があるが検出に遅れが生じたり、検出できる範囲が
限定されたりする問題があうた。Misfires in internal combustion engines can be detected by detecting exhaust temperature, exhaust gas analysis, and ion current detection, but these methods have been found to have problems such as detection delays and limited detection ranges.

この発明者は往復機関は吸入、圧縮、膨張、排気の行程
を持つ、ており、出力が出てくるのはそのうちの膨張行
程のみであり、従ってクランク軸の周速度もそれによっ
て異なり、たとえば４気筒であって、フライホールで回
転が安定化されていても膨張行程と圧縮行程ではその周
速度は異な？前者の方が速く失火が発生した時にはその
差はほとんどなくなる事に着目し、膨張行程でクランク
軸′の回転速度が加速されていない場合に失火と判定す
ることにより上記問題点が解消できる往復機関の失火検
出方法および装置を提供せんとするものである。The inventor explained that a reciprocating engine has suction, compression, expansion, and exhaust strokes, and only the expansion stroke produces output, and therefore the circumferential speed of the crankshaft varies accordingly. Even if the rotation of a cylinder is stabilized by a flyhole, is the circumferential speed different during the expansion stroke and the compression stroke? Focusing on the fact that the former is faster and the difference almost disappears when a misfire occurs, we developed a reciprocating engine that solves the above problem by determining a misfire when the rotational speed of the crankshaft' is not accelerated during the expansion stroke. The present invention aims to provide a misfire detection method and device.

本発明は往復機関の膨張工程後または膨張工程後期と、
膨張工程前または膨張工程前期とのクランク軸回転速度
差を検出し、該速度差（加ｉ）が設定−以下のときを失
火として検出することを骨子とするものであり、つぎに
本発明を図に示す一実施例に基づき説明する。The present invention is applied after the expansion process or in the latter half of the expansion process of the reciprocating engine,
The main idea is to detect the difference in crankshaft rotational speed before the expansion process or in the first half of the expansion process, and to detect a misfire when the speed difference (addition i) is less than or equal to a set value. An explanation will be given based on an example shown in the figure.

１は往復機関、２はそのクランク軸、３は該クランク軸
２の回転速度を検出するための電磁ピックアップ、４は
電磁ピックアップが検出したクランク軸２の設定角度の
周期をパルス巾に変更するパルス発生回路であり、たと
えばＩｉ２図に示す如くクランク軸２に取付けられたデ
ィスク２１の外周にクランク角の上死点のときピックア
ップが位置する点Ｐから前後６０°の点を中心に２０＠
の角度で突起２２．２３．２４．２５を設は更に点対象
の位置にも４つの突起を設け１、第３図（１）に示す電
磁ピックアップ４の前記突起２２〜２５に対応する出力
波２Ｓ／、２ｉ、２イ、２ｇを第３図（２）に示すパル
スに変更する。５は第３図（４）に示す如く往復機関の
失火検出気筒の膨張行程の全部又は設定した一部（本実
施例で、は、第３図（３）に示す点火火花放電時期から
一定期間）を表示するパルスを発生する膨張行程表示パ
ルス発生回路、６はパルス発生回路４の出力と膨張行程
表示パルス発生回路５の出力とを入力するアンド回路６
１と、パルス発生回路４の出力とインバーター６２を介
した膨張行程表示パルス発生回路５の出力とを入力とす
るアンド回路６３とを有し、パルス発生回路４の出力パ
ルスを膨張行程表示パルス発生回路５の出力パルス中白
にあるものと外にあ２ものとに区別して出力し、７はパ
ルス発生回路４の出力パルス巾を測定するパルス巾測定
回路、８は測定されたパルス巾を記憶するメモリであり
、第３図（８）に示すメモリクリアパルスより１周期ご
とにメモリが消去される。９は膨張行程前のパルス巾と
膨張行程後のパルス巾とを比較し、膨張行程後のバルー
　　本筒を表示するための失火有無表示パルスとを入力し、表
示装置１１を作動させるアンド回路である。1 is a reciprocating engine, 2 is its crankshaft, 3 is an electromagnetic pickup for detecting the rotational speed of the crankshaft 2, and 4 is a pulse for changing the cycle of the set angle of the crankshaft 2 detected by the electromagnetic pickup into a pulse width. For example, as shown in Figure Ii2, 20＠ is centered around a point 60 degrees forward and backward from the point P where the pickup is located at the top dead center of the crank angle on the outer periphery of the disk 21 attached to the crankshaft 2, as shown in Figure Ii2.
The protrusions 22, 23, 24, and 25 are provided at angles of 1 and 4 protrusions are also provided at point-symmetric positions 1 and output waves corresponding to the protrusions 22 to 25 of the electromagnetic pickup 4 shown in FIG. 3 (1) are provided. Change 2S/, 2i, 2i, and 2g to the pulses shown in FIG. 3 (2). 5 is all or a set part of the expansion stroke of the misfire detection cylinder of the reciprocating engine as shown in FIG. ), and 6 is an AND circuit 6 that inputs the output of the pulse generation circuit 4 and the output of the expansion stroke display pulse generation circuit 5.
1, and an AND circuit 63 which receives as input the output of the pulse generation circuit 4 and the output of the expansion stroke display pulse generation circuit 5 via the inverter 62, and uses the output pulse of the pulse generation circuit 4 to generate the expansion stroke display pulse. The circuit 5 outputs the output pulses by distinguishing them into white ones and two outside ones, and 7 is a pulse width measuring circuit that measures the output pulse width of the pulse generating circuit 4, and 8 is a memory for storing the measured pulse widths. The memory is erased every cycle by the memory clear pulse shown in FIG. 3 (8). 9 is an AND circuit which compares the pulse width before the expansion stroke with the pulse width after the expansion stroke, inputs a misfire display pulse for displaying the valve and main cylinder after the expansion stroke, and operates the display device 11. be.

以上の如く本発明の往復機関の失火検出方法および装置
は往復機関の膨張工程後または膨張工程後期と、膨張工
程前または膨張工程前期とのクランク軸−転適度差を検
出し、該速度差が設定値以下のときを失火として検出し
ているので失火の検出が直接的で迅速にできかつ検出の
範囲が広く、且つ正確に検出できる。As described above, the method and device for detecting a misfire in a reciprocating engine according to the present invention detects the difference in crankshaft rotation speed between the reciprocating engine after the expansion process or the latter half of the expansion process and before the expansion process or in the early expansion process, and Since a misfire is detected when the value is below the set value, misfire can be detected directly and quickly, and the detection range is wide and can be detected accurately.

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

第１図は、本発明にかかる往復機関の失火検出装置のブ
ロック図、第２図はクランク軸の回転速度検出装置の斜
視図、第３図は作動説明のための波形図である。図中　ｊ　電磁ピックアップ　参・パルス発生手続補正
書昭和ｊ４年を３８日特許庁長゛ｒ　　　　　　殿２　発明の名称　　往復機関の失火検出方法および装置
３　補正をする者事件との関係　　時評出願人住　所　　名古鳳市瑞穂区高辻ｌＩｒ／参番１１量４、
　代　　理　　人　　〒ｌ１４ｊ　　１Ｎ（６ｊＪ）？
７７−Ｊ４！Ｉｆ６　補正により増加する発明の数７、補正の対象を特許請求の範囲を次の文章とするＯｔ在復機関の膨張行程後または膨張行程後期と、膨張行
程前または膨張行程前期とのクランク軸回転速度差を検
出し、該速度差が設定値以下のときを失火として検出す
ることを特徴とする往復機関の失火検出方法。２往復機関の膨張行程後型たは膨張行程後期に股、定し
た一定角度を回転する周期ｔ１と、膨張行程前型たは膨
張行程前期に設定した一定角度を回転する周期ｔ２とを
検出する往復機関のクランク軸の回転速度検出装置と、
該周期をパルス巾に変更するパルス発生回路と、該パル
ス巾を溜室する測定回路と、周期ｔ１と周期ｔ２との差
が設定値以下のときを失火として出力する失火判別回路
と、該失火判別回路の出力表示装置とからなる往復機関
の失火検出装置０１発明の詳細な説明の橢 ψ第３ページ第２行目「膨張工程後または膨張工程」を「膨張行程後または膨
張行、程」とする。切箔３ページ第３行目「膨張工程前または膨張工程」を「膨張行程前または膨
張行程」とする。０）第ｊページ第ダ行目「膨張工程ＩＩまたは膨張工程」を「膨張行程後または
膨張行程」とする・ ■第Ｓページ第ｊ行目「膨張工程前または膨張工程」を「膨張行程前または膨
張行程」とする。FIG. 1 is a block diagram of a misfire detection device for a reciprocating engine according to the present invention, FIG. 2 is a perspective view of a crankshaft rotational speed detection device, and FIG. 3 is a waveform diagram for explaining the operation. In the figure J Electromagnetic Pickup Reference Pulse Generation Procedure Amendment Document 38th 1928 Director of the Patent Office 2 Title of Invention Method and Device for Detecting Misfires in Reciprocating Engines 3 Relationship to the Case of the Person Who Makes the Amendment Address of the Applicant for the Review Takatsuji lIr, Mizuho-ku, Nagoo City/Sanban 11 quantity 4,
Agent 〒14j 1N (6jJ)?
77-J4! If6 Number of inventions increased by amendment 7, the scope of the amendment is as follows: O t Crankshaft after expansion stroke or late expansion stroke and before expansion stroke or early expansion stroke of existing engine A misfire detection method for a reciprocating engine, comprising detecting a rotational speed difference and detecting a misfire when the speed difference is less than or equal to a set value. 2.Detects the period t1 in which the reciprocating engine rotates through a fixed angle set after the expansion stroke or in the latter half of the expansion stroke, and the period t2 in which it rotates through a fixed angle set in the pre-expansion stroke type or in the early stage of the expansion stroke. A reciprocating engine crankshaft rotation speed detection device,
A pulse generation circuit that changes the period to a pulse width, a measurement circuit that stores the pulse width, a misfire discrimination circuit that outputs a misfire when the difference between the period t1 and the period t2 is less than a set value, and the misfire. A misfire detection device for a reciprocating engine consisting of an output display device of a discriminating circuit 0. ”. The third line of page 3 of the cut foil "before the expansion process or the expansion process" is changed to "before the expansion process or the expansion process". 0) Change ``expansion process II or expansion process'' in line d of page j to ``after expansion stroke or expansion stroke'' - Change ``before expansion process or expansion process'' in line j of page S to ``before expansion stroke'' or expansion stroke.

Claims

【特許請求の範囲】り往復機関の膨張工程後または膨張工程後期と、膨張工
程前または膨張工程前期とのクランク軸回転速度差を検
出し、該速度差が設定値以下のときを失火として検出す
ることを特徴とする往復機関の失火検出方法。２往復機関の膨張工程後または膨張工程後期に設定した
一定角度を回転する周期ｔ１と、膨張工程前または膨張
工程前期に設定した一定角度を回転する周期ｔｓとを検
出する往復機関のクランク軸の回転速度検出装置と、該
周期をパルス巾に変更するパルス発生回路と、該パルス
巾を測定する測定回路と１周期ｔ１と周期ｔ！との差が
設定値以下のときを失火として出力する失火判別回路と
、該失火判別回路の出力表示装置とからなる往復機関の
失火検出装置。[Claims] A crankshaft rotational speed difference between the reciprocating engine after the expansion stroke or the latter half of the expansion stroke and before the expansion stroke or the first half of the expansion stroke is detected, and when the speed difference is less than a set value, it is detected as a misfire. A misfire detection method for a reciprocating engine, characterized by: 2. A crankshaft of a reciprocating engine that detects a period t1 of rotating a constant angle set after the expansion process or in the latter half of the expansion process of the reciprocating engine, and a period ts of rotating a constant angle set before the expansion process or in the first half of the expansion process. A rotation speed detection device, a pulse generation circuit that changes the period into a pulse width, a measurement circuit that measures the pulse width, and one period t1 and period t! A misfire detection device for a reciprocating engine, comprising a misfire discrimination circuit that outputs an output as a misfire when the difference between the two and the difference is less than a set value, and an output display device of the misfire discrimination circuit.