JP2007247608A

JP2007247608A - Ignition device for internal combustion engine

Info

Publication number: JP2007247608A
Application number: JP2006074919A
Authority: JP
Inventors: Gonosuke Inamura; 豪乃助稲村; Yoshiyuki Fukumura; 義之福村
Original assignee: Diamond Electric Manufacturing Co Ltd
Current assignee: Diamond Electric Manufacturing Co Ltd
Priority date: 2006-03-17
Filing date: 2006-03-17
Publication date: 2007-09-27

Abstract

<P>PROBLEM TO BE SOLVED: To materialize an ignition device for an internal combustion engine and an ion current detection device for the internal combustion engine which are of low cost, small sized, stable, and reliable, and does not deteriorate output performance of a spark plug. <P>SOLUTION: In the ignition device for the internal combustion engine provided with a primary coil controlling primary current on and off by electronic control by a primary current shut off element and a secondary coil electromagnetically coupled to the primary coil and supplying high voltage to the spark plug, IGBT is used for the primary current shut off element. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

本発明は、内燃機関用点火装置に係り、特に１次電流遮断素子のターンオン時に２次コイルに発生する高電圧を１次電流遮断素子の制御によって抑制する内燃機関用点火装置に関するものである。 The present invention relates to an ignition device for an internal combustion engine, and more particularly to an ignition device for an internal combustion engine that suppresses a high voltage generated in a secondary coil when the primary current interruption element is turned on by controlling the primary current interruption element.

図６において内燃機関用点火装置は、１次コイルと前記１次コイルに電磁結合されて点火プラグ１に高電圧を供給する２次コイルとで構成された点火コイル２と、１次電流遮断時に２次コイルに発生する高電圧を抑制するオン点火防止用ダイオード３、点火タイミングに点火信号を発生させる制御回路４と、制御回路４からの点火信号に基づき点火コイル２の１次電流を遮断する１次電流遮断素子５を含む構成となっている。 In FIG. 6, the ignition device for an internal combustion engine includes an ignition coil 2 composed of a primary coil and a secondary coil that is electromagnetically coupled to the primary coil and supplies a high voltage to the spark plug 1, and when the primary current is interrupted. An on-ignition prevention diode 3 that suppresses a high voltage generated in the secondary coil, a control circuit 4 that generates an ignition signal at the ignition timing, and a primary current of the ignition coil 2 is cut off based on the ignition signal from the control circuit 4 The primary current interrupting element 5 is included.

又、１次電流遮断時に２次コイルに発生する高電圧を抑制する手段として、オン点火防止用ダイオードを用いず図７の用に１次電流遮断素子を制御する方法も知られている。 Further, as a means for suppressing a high voltage generated in the secondary coil when the primary current is interrupted, a method of controlling the primary current interrupting element as shown in FIG. 7 without using the on-ignition preventing diode is also known.

制御回路４には、例えば、点火信号が所定値以上に長くなった場合や、点火信号を発生する制御装置のＧＮＤ電位が点火電源のＧＮＤ電位よりも上昇した場合に生じる連続通電状態に対する遮断回路を設けたものや、電源電圧の異常により発生するスイッチング素子の過電流に対する電流制限回路を設けたものなどがある。前記１次電流遮断素子５の保護制御は、点火信号が所定値以上に長くなった場合や、バッテリー電源の異常により発生する１次電流遮断素子５の過電流に対して、点火コイル２の一次コイルと１次電流遮断素子５に直列に挿入した電流検出抵抗と、その端子電圧と基準電源の所定の電圧を比較した結果をもとに１次電流遮断素子５の入力を制御することで所定値以上の電流が流れないように制御する過電流保護である。 The control circuit 4 includes, for example, a cutoff circuit for a continuous energization state that occurs when the ignition signal becomes longer than a predetermined value or when the GND potential of the control device that generates the ignition signal rises above the GND potential of the ignition power source. And a circuit provided with a current limiting circuit for overcurrent of the switching element caused by an abnormality in the power supply voltage. The protection control of the primary current interrupting element 5 is performed by the primary control of the ignition coil 2 against an overcurrent of the primary current interrupting element 5 that occurs when the ignition signal becomes longer than a predetermined value or when the battery power supply is abnormal. A predetermined value is obtained by controlling the input of the primary current interrupting element 5 based on a result of comparing a current detection resistor inserted in series with the coil and the primary current interrupting element 5 and a terminal voltage thereof with a predetermined voltage of the reference power source. This is overcurrent protection that controls so that current exceeding the value does not flow.

内燃機関用点火装置において、１次電流遮断素子のターンオン時に２次コイルに発生する高電圧は、点火コイルの１次コイルと２次コイルが電磁結合されていることによるもので、すなわち１次電流遮断素子がターンオンしたときのＶｃｅと電源電圧の差分が２次側へ伝達されることによって発生するものであり、点火コイルの性質上不可避の現象である。 In the ignition device for an internal combustion engine, the high voltage generated in the secondary coil when the primary current interrupting element is turned on is due to the electromagnetic coupling between the primary coil and the secondary coil of the ignition coil, that is, the primary current. This occurs when the difference between Vce and the power supply voltage when the shut-off element is turned on is transmitted to the secondary side, and is an inevitable phenomenon due to the nature of the ignition coil.

１次電流遮断素子のターンオン時に２次コイルに発生する高電圧を抑制する手段としては前述のオン点火防止ダイオードを用いられるが、このダイオードの搭載を考慮した点火コイル設計が必要であり、小型・軽量化、低コスト化の障壁となっている。 The above-mentioned on-ignition prevention diode is used as a means for suppressing the high voltage generated in the secondary coil when the primary current interrupting element is turned on. However, the ignition coil design considering the mounting of this diode is necessary, It is a barrier to weight reduction and cost reduction.

又、前述のオン点火防止ダイオードを用いる場合、２次コイルにイオン電流検出回路が接続される内燃機関用イオン電流検出装置において、イオン電流検出に必要な電流経路、イオン電流検出回路→２次コイル→点火プラグ→ＧＮＤ→イオン電流検出回路、のループを構成出来ないという問題がある。 Further, in the case of using the above-described on-ignition prevention diode, in the ion current detection device for an internal combustion engine in which the ion current detection circuit is connected to the secondary coil, the current path necessary for ion current detection, the ion current detection circuit → the secondary coil There is a problem that a loop of ignition plug → GND → ion current detection circuit cannot be configured.

内燃機関用イオン電流検出装置において、上述の課題を解決するためには点火コイルの巻数比を落として２次コイルに発生する電圧を落とすことになるが、同時に点火性能も低下する。 In the ion current detection device for an internal combustion engine, in order to solve the above-mentioned problem, the turn ratio of the ignition coil is reduced to lower the voltage generated in the secondary coil, but at the same time, the ignition performance is also lowered.

図７に示す１次電流遮断素子制御による１次電流遮断素子のターンオン時に２次コイルに発生する。高電圧の抑制方法では、１次電流遮断素子のオン遅れ時間が発生する為、１次電流の立ち上がり特性が低下してしまい、１次側への投入エネルギが減少することによる２次出力エネルギの低下或いはＥ／ＧＥＣＵの点火コイルの１次電流通電時間の設定値を変更する必要が生じる。 It occurs in the secondary coil when the primary current interrupting element is turned on by the primary current interrupting element control shown in FIG. In the high voltage suppression method, the primary current interrupting element has an on-delay time, so that the rising characteristic of the primary current is deteriorated, and the secondary output energy is reduced by reducing the input energy to the primary side. It is necessary to reduce or change the set value of the primary current energization time of the ignition coil of the E / GECU.

本発明は、上記の問題点に鑑みてなされたものであって、安価に小型で安定的で信頼性が高く、且つ点火コイルの出力性能を低下させることの無い内燃機関用点火装置及び内燃機関用イオン電流検出装置を実現することを目的とする。 The present invention has been made in view of the above problems, and is an ignition device for an internal combustion engine and an internal combustion engine that is inexpensive, small, stable, reliable, and does not deteriorate the output performance of the ignition coil. An object of the present invention is to realize an ion current detection device for an automobile.

１次電流遮断素子のターンオン時には２次コイルに図３に示す電流が相互誘導作用にり発生する。この時に２次コイルには電流と同様に相互誘導作用により高電圧が発生し、この電圧が高すぎるとE/Gの点火時期の進角（過早着火）を引き起こす原因となる。
そこで、この２次コイルに発生する電流を検出する手段を用いることが出来れば、２次コイルに発生する電流値に対して１次電流遮断素子のターンオン制御を行い、Ｖｃｅ−電源電圧の差分を任意に調整しながら１次電流遮断素子をターンオンすることができ、前記の２次コイル発生電圧を抑制することが出来る。 When the primary current interrupting element is turned on, the current shown in FIG. 3 is generated in the secondary coil due to the mutual induction action. At this time, a high voltage is generated in the secondary coil due to mutual induction as in the case of current, and if this voltage is too high, it leads to the advance of the ignition timing (premature ignition) of the E / G.
Therefore, if a means for detecting the current generated in the secondary coil can be used, the turn-on control of the primary current cutoff element is performed for the current value generated in the secondary coil, and the difference between Vce and the power supply voltage is calculated. The primary current interrupting element can be turned on while arbitrarily adjusting, and the secondary coil generation voltage can be suppressed.

前述の課題を解決する為、本発明では次の構成とする。すなわち、１次電流遮断素子による電子制御によって１次電流がオンオフ制御される１次コイルと、前記１次コイルに電磁結合されて点火プラグに高電圧を供給する２次コイルを備えた内燃機関用点火装置において、２次コイル低圧側に２次コイル電流を検出する電流電圧変換回路と、前記電流電圧変換回路の出力が入力され、任意の電圧（Ｖth）と比較を行う比較器の出力が１次電流遮断素子の駆動回路に入力される。 In order to solve the above-described problems, the present invention has the following configuration. That is, for an internal combustion engine comprising a primary coil whose primary current is on / off controlled by electronic control by a primary current interrupting element, and a secondary coil that is electromagnetically coupled to the primary coil and supplies a high voltage to a spark plug. In the ignition device, a current-voltage conversion circuit for detecting a secondary coil current on the secondary coil low-voltage side and an output of the current-voltage conversion circuit are input, and an output of a comparator for comparing with an arbitrary voltage (Vth) is 1. It is input to the drive circuit for the secondary current interrupting element.

但し、このままでは点火時期以外での誤点火の恐れがあるため、１次電流遮断素子の駆動回路に入力される前記比較器の出力は、点火信号同期回路によって内燃機関用点火装置或いは内燃機関用イオン電流検出装置に入力される点火信号に同期して回路出力動作を行うよう制御される。 However, since there is a risk of mis-ignition other than the ignition timing in this state, the output of the comparator input to the drive circuit of the primary current interrupting element is output to the internal combustion engine ignition device or internal combustion engine by the ignition signal synchronization circuit. Control is performed so that the circuit output operation is performed in synchronization with the ignition signal input to the ion current detector.

１次電流遮断素子の制御回路は内燃機関用点火装置或いは内燃機関用イオン電流検出装置に入力される点火信号によってターンオン動作を開始する１次電流遮断素子に対して、電流電圧変換回路より入力された信号と、任意に設定出来る電圧（Vth）と比較する比較器の出力動作によって、１次電流遮断素子のゲート寄生容量に充電された電荷を放電し１次電流遮断素子のゲート電圧を引き下げる動作を行う。その結果、２次コイルに発生する誘導電流は減少し、前記比較器の出力動作が反転すると再び１次電流遮断素子のターンオン動作を開始する。この動作はターンオン時に２次コイルに発生する電流によって出力される電流電圧変換回路の出力電圧が任意の比較電圧（Vth）を下回るまで繰り返され、最終的には１次電流遮断素子をターンオンさせる。 The control circuit for the primary current interrupting element is input from the current-voltage conversion circuit to the primary current interrupting element that starts the turn-on operation by the ignition signal input to the internal combustion engine ignition device or the internal combustion engine ion current detection device. The operation of reducing the gate voltage of the primary current interrupting element by discharging the charge charged in the gate parasitic capacitance of the primary current interrupting element by the output operation of the comparator that compares the signal and the voltage (Vth) that can be arbitrarily set I do. As a result, the induced current generated in the secondary coil is reduced, and when the output operation of the comparator is reversed, the turn-on operation of the primary current interrupting element is started again. This operation is repeated until the output voltage of the current-voltage conversion circuit output by the current generated in the secondary coil at turn-on falls below an arbitrary comparison voltage (Vth), and finally the primary current interrupting element is turned on.

前記繰り返し動作中の１次電流遮断素子のＣ−Ｅ間は、完全にターンオンされた時の動作点と異なる状態でバイアスされる為、通電状態が維持され１次電流の立ち上がり特性を低下させることなく１次電流遮断素子のターンオン時に２次コイルに発生する高電圧を抑制することができる。 Between the CE of the primary current interrupting element during the repetitive operation is biased in a state different from the operating point when it is completely turned on, the energized state is maintained and the rising characteristic of the primary current is deteriorated. The high voltage generated in the secondary coil when the primary current interrupting element is turned on can be suppressed.

又、前述の電流電圧変換回路は内燃機関用イオン電流検出装置における電流電圧変換回路と同様であり、イオン電流検出回路によって代用することが可能である。本発明は組み合わされる１次及び２次コイルに依存することなく、１次電流遮断素子のターンオン時に２次コイルに生じる高電圧を抑制し、安定的で小型、軽量で安価な内燃機関用点火装置及び内燃機関用イオン電流検出装置を実現できる。 The current-voltage conversion circuit described above is the same as the current-voltage conversion circuit in the ion current detection device for internal combustion engines, and can be replaced by an ion current detection circuit. The present invention suppresses a high voltage generated in the secondary coil when the primary current interrupting element is turned on without depending on the combined primary and secondary coils, and is a stable, small, light and inexpensive ignition device for an internal combustion engine. And the ion current detection apparatus for internal combustion engines is realizable.

本発明の実施例は、１次電流遮断素子による電子制御によって１次電流がオンオフされる１次コイルと、前記１次コイルに電磁結合されて点火プラグに高電圧を供給する２次コイルと、前記１次コイルと前記２次コイルを内包するコイルケースを備える内燃機関用点火装置において、具体的には参考例として示す図１の様な回路によって、２次コイル低圧側に電流電圧変換回路６を配置し、電源電圧変換回路の入力部に電流検出用ダイオード８、９を接続する。電流電圧変換回路の出力は基準電圧比較回路７に入力され、基準電圧比較回路の出力は１次電流遮断素子の駆動回路３に接続されている。駆動回路３は内燃機関用点火装置に点火信号が入力されている期間に限り、基準電圧比較回路７から入力された信号に対して１次電流遮断素子４を動作点を変化させながら最終的にターンオンさせる。電流電圧変換回路６及び基準電圧比較回路７は１次電流遮断素子の駆動回路３及び保護回路と共にＩＣ上に容易に形成できる。 An embodiment of the present invention includes a primary coil in which a primary current is turned on / off by electronic control by a primary current interrupting element, a secondary coil that is electromagnetically coupled to the primary coil and supplies a high voltage to a spark plug, In an internal combustion engine ignition device including a coil case containing the primary coil and the secondary coil, specifically, a current-voltage conversion circuit 6 is connected to the secondary coil low-voltage side by a circuit as shown in FIG. 1 as a reference example. And the current detection diodes 8 and 9 are connected to the input of the power supply voltage conversion circuit. The output of the current-voltage conversion circuit is input to the reference voltage comparison circuit 7, and the output of the reference voltage comparison circuit is connected to the drive circuit 3 of the primary current cutoff element. Only when the ignition signal is input to the internal combustion engine ignition device, the drive circuit 3 finally changes the operating point of the primary current interrupting element 4 with respect to the signal input from the reference voltage comparison circuit 7. Turn on. The current-voltage conversion circuit 6 and the reference voltage comparison circuit 7 can be easily formed on the IC together with the drive circuit 3 and the protection circuit for the primary current cutoff element.

又、内燃機関用イオン電流検出装置において、１次電流遮断素子による電子制御によって１次電流がオンオフされる１次コイルと、前記１次コイルに電磁結合されて点火プラグに高電圧を供給する２次コイルと、点火プラグの点火動作に基づく燃焼動作によって燃焼室に発生したイオン電流を検出する検出回路と、前記１次コイルと前記２次コイルを内包するコイルケースを備える内燃機関用イオン電流検出装置において、具体的には参考例として示す図２の様な回路によって、イオン電流を電圧変換する電流電圧変換回路６の出力は基準電圧比較回路７に入力され、基準電圧比較回路の出力は１次電流遮断素子の駆動回路３に接続されている、駆動回路３は内燃機関用点火装置に点火信号が入力されている期間に限り、基準電圧比較回路７から入力された信号に対して１次電流遮断素子４を動作点を変化させながら最終的にターンオンさせる。
電流電圧変換回路６及び基準電圧比較回路７は１次電流遮断素子の駆動回路３及び保護回路と共にＩＣ上に容易に形成できる。 Further, in the ion current detection device for an internal combustion engine, a primary coil whose primary current is turned on and off by electronic control by a primary current interrupting element, and a high voltage to the spark plug that is electromagnetically coupled to the primary coil 2 Ion current detection for an internal combustion engine comprising a secondary coil, a detection circuit for detecting an ionic current generated in the combustion chamber by a combustion operation based on an ignition operation of a spark plug, and a coil case containing the primary coil and the secondary coil In the apparatus, specifically, the output of the current-voltage conversion circuit 6 for converting the ionic current into a voltage is input to the reference voltage comparison circuit 7 by a circuit as shown in FIG. 2 as a reference example, and the output of the reference voltage comparison circuit is 1 The drive circuit 3, which is connected to the drive circuit 3 for the secondary current interrupting element, is connected to the reference voltage comparison circuit 7 only during the period when the ignition signal is input to the internal combustion engine ignition device. Finally it turns on while changing the operating point of the primary current cut-off device 4 with respect et input signal.
The current-voltage conversion circuit 6 and the reference voltage comparison circuit 7 can be easily formed on the IC together with the drive circuit 3 and the protection circuit for the primary current cutoff element.

以上のように、本発明の実施の形態について説明したが、実施の形態は上記形態に特に限定されるものではない。当該点火装置が必要なあらゆるエンジンに使用できるものであり、サイズにおいても用途に応じて適宜拡大縮小して使用できるものであることはいうまでもなく、この発明の精神に基づき当業者が行いうる種々の変形的形態、改良的形態で実施することも可能である。 As mentioned above, although embodiment of this invention was described, embodiment is not specifically limited to the said form. Needless to say, the ignition device can be used for any necessary engine, and can be appropriately enlarged or reduced in size according to the application, and can be performed by those skilled in the art based on the spirit of the present invention. It is also possible to carry out various modifications and improvements.

内燃機関用点火装置の回路図Circuit diagram of ignition device for internal combustion engine 内燃機関用イオン電流検出装置の回路図Circuit diagram of ion current detector for internal combustion engine １次電流遮断素子のターンオン時に発生する２次コイル電流と電圧の波形Secondary coil current and voltage waveforms generated when the primary current interrupting element is turned on １次電流遮断素子のゲート入力信号の制御方法Method for controlling gate input signal of primary current interrupting element １次電流遮断素子のゲート入力信号制御時の２次コイル電圧波形Secondary coil voltage waveform when controlling the gate input signal of the primary current interrupter 従来の内燃機関用点火装置の回路図Circuit diagram of a conventional internal combustion engine ignition device 図６における１次電流遮断素子の制御波形Control waveform of the primary current interrupt device in FIG.

符号の説明Explanation of symbols

３駆動回路
４１次電流遮断素子
６電流電圧変換回路
７基準電圧比較回路
８、９電流検出用ダイオード 3 Drive circuit 4 Primary current interrupting element 6 Current-voltage conversion circuit 7 Reference voltage comparison circuit 8, 9 Current detection diode

Claims

１次電流遮断素子による電子制御によって１次電流がオンオフ制御される１次コイルと、前記１次コイルに電磁結合されて点火プラグに高電圧を供給する２次コイルと、を備えた内燃機関用点火装置において、１次電流遮断素子にＩＧＢＴを使用していることを特徴とする内燃機関用点火装置。 An internal combustion engine comprising: a primary coil whose primary current is on / off controlled by electronic control by a primary current interrupting element; and a secondary coil that is electromagnetically coupled to the primary coil and supplies a high voltage to a spark plug An ignition device for an internal combustion engine, wherein an IGBT is used as a primary current interrupting element in the ignition device.

前記内燃機関用点火装置において、１次電流遮断素子のターンオン時に２次コイルに発生する高電圧を抑制する為、１次電流遮断素子の制御手段をもっていることを特徴とする内燃機関用点火装置。 In the internal combustion engine ignition device, the primary current interruption element has a control means for suppressing the high voltage generated in the secondary coil when the primary current interruption element is turned on.

前記内燃機関用点火装置において、２次コイルに発生する電流を検出する手段を持っていることを特徴とする内燃機関用点火装置。 In the internal combustion engine ignition device, the internal combustion engine ignition device has means for detecting a current generated in the secondary coil.

前記内燃機関用点火装置において、請求項３の手段によって２次コイルに発生する電流を検出し、発生した電流の大きさに応じて請求項２の手段により１次電流遮断素子を制御し、１次電流遮断素子のターンオン時に２次コイルに発生する高電圧を抑制することを特徴とする内燃機関用点火装置。 In the internal combustion engine ignition device, the current generated in the secondary coil is detected by the means of claim 3, and the primary current interrupting element is controlled by the means of claim 2 according to the magnitude of the generated current. An ignition device for an internal combustion engine, wherein a high voltage generated in a secondary coil when a secondary current interrupting element is turned on is suppressed.

請求項３の手段を併せ持つイオン電流検出回路によって、２次コイル側の点火プラグの点火動作に基づく燃焼動作によって燃焼室に発生したイオン電流を検出することを特徴とする内燃機関用イオン電流検出装置。 An ion current detection device for an internal combustion engine, wherein an ion current generated in a combustion chamber by a combustion operation based on an ignition operation of a spark plug on a secondary coil side is detected by an ion current detection circuit having the means of claim 3 .