JP2006070882A - Accumulator fuel injection device - Google Patents

Accumulator fuel injection device Download PDF

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JP2006070882A
JP2006070882A JP2004258804A JP2004258804A JP2006070882A JP 2006070882 A JP2006070882 A JP 2006070882A JP 2004258804 A JP2004258804 A JP 2004258804A JP 2004258804 A JP2004258804 A JP 2004258804A JP 2006070882 A JP2006070882 A JP 2006070882A
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fuel
common rail
value
supply
pressure
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JP4329653B2 (en
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Kazuhiko Oshima
和彦 大島
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Denso Corp
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Denso Corp
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    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
    • F02D—CONTROLLING COMBUSTION ENGINES
    • F02D41/00—Electrical control of supply of combustible mixture or its constituents
    • F02D41/30—Controlling fuel injection
    • F02D41/38—Controlling fuel injection of the high pressure type
    • F02D41/3809—Common rail control systems
    • F02D41/3836—Controlling the fuel pressure
    • F02D41/3845—Controlling the fuel pressure by controlling the flow into the common rail, e.g. the amount of fuel pumped
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
    • F02D—CONTROLLING COMBUSTION ENGINES
    • F02D41/00—Electrical control of supply of combustible mixture or its constituents
    • F02D41/24—Electrical control of supply of combustible mixture or its constituents characterised by the use of digital means
    • F02D41/2406—Electrical control of supply of combustible mixture or its constituents characterised by the use of digital means using essentially read only memories
    • F02D41/2425—Particular ways of programming the data
    • F02D41/2429—Methods of calibrating or learning
    • F02D41/2451—Methods of calibrating or learning characterised by what is learned or calibrated
    • F02D41/2464—Characteristics of actuators
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
    • F02D—CONTROLLING COMBUSTION ENGINES
    • F02D2200/00—Input parameters for engine control
    • F02D2200/02—Input parameters for engine control the parameters being related to the engine
    • F02D2200/06—Fuel or fuel supply system parameters
    • F02D2200/0602—Fuel pressure
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
    • F02D—CONTROLLING COMBUSTION ENGINES
    • F02D41/00—Electrical control of supply of combustible mixture or its constituents
    • F02D41/30—Controlling fuel injection
    • F02D41/38—Controlling fuel injection of the high pressure type
    • F02D41/3809—Common rail control systems
    • F02D41/3836—Controlling the fuel pressure
    • F02D41/3863—Controlling the fuel pressure by controlling the flow out of the common rail, e.g. using pressure relief valves

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  • Engineering & Computer Science (AREA)
  • Chemical & Material Sciences (AREA)
  • Combustion & Propulsion (AREA)
  • Mechanical Engineering (AREA)
  • General Engineering & Computer Science (AREA)
  • Fuel-Injection Apparatus (AREA)
  • Electrical Control Of Air Or Fuel Supplied To Internal-Combustion Engine (AREA)
  • Combined Controls Of Internal Combustion Engines (AREA)

Abstract

<P>PROBLEM TO BE SOLVED: To accurately correct instruction value characteristics indicating the correlation of the supplied amount Q of a fuel to a common rail to a drive current value Iscv provided to a suction metering valve 20 for metering the fuel. <P>SOLUTION: When an injector does not perform the injection and supply of a fuel, the drive current value Iscv is reduced from a zero supply amount guaranteed value IscvO', and based on the estimation of the change rate of a common rail pressure in that reduction, a supply start drive current value Oscv0 is determined. Thus, when the supply of the fuel to the common rail is started, the trend of change in the common rail pressure definitely changes from a state in which it lowers according to only a leak amount from the injector. Accordingly, the supply start drive current value Oscv0 can be provided by using the change rate of the common rail pressure indicating the trend of the change in the common rail pressure. As a result, the instruction value characteristics can be accurately corrected. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

本発明は、燃料を蓄圧するコモンレールを備え、コモンレールを介して内燃機関（エンジン）の気筒に燃料を噴射供給する蓄圧式燃料噴射装置に関する。   The present invention relates to a pressure accumulation type fuel injection device that includes a common rail for accumulating fuel, and injects fuel into a cylinder of an internal combustion engine (engine) via the common rail.

〔従来の技術〕
従来より、ディーゼルエンジン等の気筒に燃料を噴射供給するため、燃料を蓄圧するコモンレールを備えた蓄圧式燃料噴射装置が用いられている。蓄圧式燃料噴射装置は、燃料を高圧状態で蓄圧するコモンレール、燃料を高圧化しコモンレールへ供給する燃料供給ポンプ、気筒ごとに搭載されコモンレールの高圧燃料を気筒に噴射供給するインジェクタ、燃料供給ポンプやインジェクタ等を制御する電子制御装置（ＥＣＵ）を備える。 [Conventional technology]
2. Description of the Related Art Conventionally, in order to inject and supply fuel to a cylinder such as a diesel engine, a pressure accumulation type fuel injection device including a common rail for accumulating fuel has been used. The accumulator type fuel injection device includes a common rail for accumulating fuel in a high pressure state, a fuel supply pump for increasing the pressure of the fuel and supplying the fuel to the common rail, an injector mounted on each cylinder and supplying the common rail high pressure fuel to the cylinder, a fuel supply pump and an injector And an electronic control unit (ECU) for controlling the components.

蓄圧式燃料噴射装置は、エンジンの運転状態（例えば、エンジン回転数）に応じてコモンレールの燃料圧力（コモンレール圧）を制御するため、燃料供給ポンプによるコモンレールへの燃料の供給量Ｑを調節する。   The accumulator type fuel injection device adjusts the fuel supply amount Q to the common rail by the fuel supply pump in order to control the fuel pressure (common rail pressure) of the common rail in accordance with the operating state of the engine (for example, the engine speed).

この供給量Ｑの調節は、燃料供給ポンプの加圧室に吸入される燃料を調量する吸入調量弁１００により行われている。すなわち、吸入調量弁１００は、コモンレールへ供給される燃料を調量する調量手段である。この吸入調量弁１００は、図６（ｂ）に示すように、通電により磁気吸引力を発生させるソレノイド１０１、磁気吸引され燃料通路の開口面積を調節する弁体１０２、弁体１０２を磁気吸引力の逆方向に付勢するスプリング１０３、および弁体１０２を保持する弁ボディ１０４等から構成されている。   The adjustment of the supply amount Q is performed by an intake metering valve 100 for metering the fuel sucked into the pressurizing chamber of the fuel supply pump. That is, the intake metering valve 100 is a metering means for metering the fuel supplied to the common rail. As shown in FIG. 6B, the intake metering valve 100 includes a solenoid 101 that generates a magnetic attractive force when energized, a valve body 102 that is magnetically attracted to adjust the opening area of the fuel passage, and a magnetically attracted valve body 102. It comprises a spring 103 that urges the force in the reverse direction, a valve body 104 that holds the valve body 102, and the like.

そして、ＥＣＵが、目標とするコモンレール圧に応じて必要とする供給量Ｑを算出し、この供給量Ｑの算出値に応じて、吸入調量弁１００へ与える指令値としてソレノイド１０１の通電量（駆動電流値Ｉｓｃｖ）を算出する。これにより、ソレノイド１０１に駆動電流値Ｉｓｃｖに相当する通電が行われ、燃料通路の開口面積が供給量Ｑに応じた大きさに調節される。したがって、ＥＣＵから与えられた駆動電流値Ｉｓｃｖと供給量Ｑとが所定の相関を有することを要求されている。
しかし、駆動電流値Ｉｓｃｖと供給量Ｑとの相関は、スプリング１０３のセット荷重の経時変化、およびソレノイド１０１の磁気吸引力の経時変化等により変動する虞がある。 Then, the ECU calculates the required supply amount Q according to the target common rail pressure, and according to the calculated value of the supply amount Q, the energization amount of the solenoid 101 (as a command value to be given to the intake metering valve 100 ( A drive current value Iscv) is calculated. As a result, the solenoid 101 is energized corresponding to the drive current value Iscv, and the opening area of the fuel passage is adjusted to a size corresponding to the supply amount Q. Therefore, it is required that the drive current value Iscv given from the ECU and the supply amount Q have a predetermined correlation.
However, the correlation between the drive current value Iscv and the supply amount Q may vary due to changes in the set load of the spring 103 with time, changes in the magnetic attraction force of the solenoid 101 with time, and the like.

そこで、アイドリング時の駆動電流値Ｉｓｃｖ（アイドル駆動電流値Ｉｓｃｖｉ）を用いて、駆動電流値Ｉｓｃｖと供給量Ｑとの相関を示す指令値特性を補正する技術が公知となっている。この技術によれば、アイドル駆動電流値Ｉｓｃｖｉを用いて、吸入調量弁１００が実際に吸入を開始する駆動電流値Ｉｓｃｖ（すなわち、実際にコモンレールへの燃料の供給を開始する駆動電流値Ｉｓｃｖ：以下、供給開始駆動電流値Ｉｓｃｖ０と呼ぶ）を学習する。そして、供給開始駆動電流値Ｉｓｃｖ０の学習値を用いて指令値特性を補正する。   Therefore, a technique for correcting the command value characteristic indicating the correlation between the drive current value Iscv and the supply amount Q using the drive current value Iscv (idle drive current value Iscv) at idling is known. According to this technique, using the idle drive current value Isvvi, the drive current value Iscv that the intake metering valve 100 actually starts to suck (that is, the drive current value Iscv that actually starts the supply of fuel to the common rail: Hereinafter, the supply start drive current value Iscv0 is learned). Then, the command value characteristic is corrected using the learning value of the supply start drive current value Iscv0.

例えば、図６（ａ）に示すように、ノーマリオープン型の吸入調量弁１００の供給開始駆動電流値Ｉｓｃｖ０は、アイドル駆動電流値Ｉｓｃｖｉと、アイドリング時のエンジン回転数（アイドル回転数）と、アイドリング時のインジェクタによる噴射量（アイドル噴射量ｑｉ）、およびアイドリング時のインジェクタからのリーク量（アイドルリーク量Ｌｉ）を用いて算出される。   For example, as shown in FIG. 6A, the supply start drive current value Iscv0 of the normally open suction metering valve 100 includes an idle drive current value Isvvi, an engine speed at idling (idle speed), and It is calculated using the injection amount (idle injection amount qi) by the injector during idling and the leak amount (idle leak amount Li) from the injector during idling.

すなわち、アイドリング時の供給量Ｑはアイドル噴射量ｑｉとアイドルリーク量Ｌｉとの和になるので、アイドル回転数に相当する勾配を有し、かつ図６（ａ）の座標（Ｉｓｃｖｉ、ｑｉ＋Ｌｉ）を通る相関線を描き、この相関線が横軸（駆動電流値Ｉｓｃｖの軸）と交差するときの駆動電流値Ｉｓｃｖが、供給開始駆動電流値Ｉｓｃｖ０の学習値となる。そして、供給開始駆動電流値Ｉｓｃｖ０の学習値に基づいて、アイドル回転数以外のエンジン回転数における相関線が更新され、指令値特性の補正が終了する。   That is, since the supply amount Q at idling is the sum of the idle injection amount qi and the idle leak amount Li, the supply amount Q has a gradient corresponding to the idle speed and the coordinates (Iscvi, qi + Li) in FIG. A correlation line passing through is drawn, and the drive current value Iscv when this correlation line intersects the horizontal axis (axis of the drive current value Iscv) becomes the learning value of the supply start drive current value Iscv0. Then, based on the learning value of the supply start drive current value Iscv0, the correlation line at the engine speed other than the idle speed is updated, and the correction of the command value characteristics is completed.

また、アイドリング時に、吸入調量弁１００による燃料の吸入量がゼロであることが保証される状態（すなわち、供給量Ｑがゼロであることが保証される状態）から駆動電流値Ｉｓｃｖを徐々に変化させ、このときのコモンレール圧の変化量、アイドル噴射量ｑｉおよびアイドルリーク量Ｌｉを用いて、供給開始駆動電流値Ｉｓｃｖ０を学習する技術も公知となっている（例えば、特許文献１参照）。   Further, during idling, the drive current value Iscv is gradually increased from a state in which the fuel intake amount by the intake metering valve 100 is guaranteed to be zero (that is, a state in which the supply amount Q is guaranteed to be zero). A technique for learning the supply start drive current value Iscv0 using the change amount of the common rail pressure, the idle injection amount qi, and the idle leak amount Li at this time is also known (see, for example, Patent Document 1).

〔従来技術の不具合〕
ところで、アイドル噴射量ｑｉおよびアイドルリーク量Ｌｉは、燃料粘度の変動やインジェクタの劣化の影響を受けて変動するが、これらの現在値を計測することは極めて困難である。このため、供給開始駆動電流値Ｉｓｃｖ０の学習に用いられるアイドル噴射量ｑｉやアイドルリーク量Ｌｉの値は、従来の実績等に基づく推定値である。したがって、供給開始駆動電流値Ｉｓｃｖ０の学習値は、真値との間に誤差を有する値になるので、指令値特性は必ずしも正確に補正されない。
特開２００１−８２２３０号公報 [Problems with conventional technology]
By the way, the idle injection amount qi and the idle leak amount Li vary under the influence of the variation in fuel viscosity and the deterioration of the injector, but it is extremely difficult to measure these current values. For this reason, the values of the idle injection amount qi and the idle leak amount Li used for learning the supply start drive current value Iscv0 are estimated values based on the conventional performance. Therefore, the learned value of the supply start drive current value Iscv0 is a value having an error between the true value and the command value characteristic is not necessarily corrected accurately.
JP 2001-82230 A

本発明は、上記の問題点を解決するためになされたものであり、蓄圧式燃料噴射装置において、コモンレールへの燃料の供給量と、この供給量に応じて燃料を調量する調量手段に与えられる指令値との相関を示す指令値特性を正確に補正することにある。   The present invention has been made to solve the above-described problems. In the accumulator fuel injection device, the amount of fuel supplied to the common rail and the metering means for metering the fuel according to the amount supplied The command value characteristic indicating the correlation with the given command value is accurately corrected.

〔請求項１の手段〕
請求項１に記載の蓄圧式燃料噴射装置の供給開始値学習手段は、インジェクタが燃料の噴射供給を行っていないときに、調量手段に与える指令値を、コモンレールへの燃料の供給量がゼロであることを保証する値から変化させる指令値増減手段と、指令値増減手段が実行されているときに、レール圧検出信号を用いて算出されるコモンレールの燃料圧力の変化率に基づき、供給開始値を決定する第１供給開始値演算手段とを有する。
コモンレールへの燃料の供給量をゼロにすると、コモンレール圧は、インジェクタからのリーク量のみに応じて低下し、やがて、インジェクタからのリークがなくなり、一定値に安定する。
そこで、インジェクタが燃料の噴射供給を行っていない状態で、指令値を、コモンレールへの燃料の供給量がゼロであることを保証する値に変更し、その後、指令値増減手段を実行し、コモンレールへの燃料の供給を開始する方向に指令値を変化させる。これにより、コモンレールへの燃料の供給が開始されると、コモンレール圧の変化の傾向は、インジェクタからのリーク量のみに応じて低下する状態から、明確に変わる。よって、第１供給開始値演算手段により、コモンレール圧の変化の傾向を示すコモンレール圧の変化率に基づき供給開始値を決定すれば、正確に供給開始値を求めることができる。この結果、指令値特性を正確に補正することができる。 [Means of Claim 1]
The supply start value learning means of the accumulator fuel injection device according to claim 1 is configured such that when the injector is not injecting and supplying fuel, a command value given to the metering means is zero when the fuel supply amount to the common rail is zero. Command value increasing / decreasing means that changes from a value that guarantees that, and when the command value increasing / decreasing means is being executed, supply starts based on the rate of change of the fuel pressure of the common rail calculated using the rail pressure detection signal First supply start value calculating means for determining a value.
When the amount of fuel supplied to the common rail is reduced to zero, the common rail pressure decreases according to only the amount of leakage from the injector, and eventually the leakage from the injector disappears and stabilizes to a constant value.
Therefore, the command value is changed to a value that guarantees that the amount of fuel supplied to the common rail is zero while the injector is not injecting and supplying fuel, and then the command value increasing / decreasing means is executed, The command value is changed in the direction in which fuel supply to the vehicle is started. As a result, when the supply of fuel to the common rail is started, the tendency of the change in the common rail pressure clearly changes from a state in which it decreases according to only the amount of leakage from the injector. Therefore, if the supply start value is determined based on the change rate of the common rail pressure indicating the change tendency of the common rail pressure by the first supply start value calculating means, the supply start value can be obtained accurately. As a result, the command value characteristic can be accurately corrected.

〔請求項２の手段〕
請求項２に記載の蓄圧式燃料噴射装置の供給開始値学習手段は、インジェクタが燃料の噴射供給を行っていないときに、調量手段に与える指令値を、コモンレールへの燃料の供給量がゼロであることを保証する値から変化させる指令値増減手段と、指令値増減手段が実行されているときに、レール圧検出信号を用いて算出されるコモンレールの燃料圧力の計測値と、コモンレールへの燃料の供給量がゼロの状態が続くと仮定した場合のコモンレールの燃料圧力の仮定値との差に基づき、供給開始値を決定する第２供給開始値演算手段とを有する。
これにより、指令値増減手段が実行されコモンレールへの燃料の供給が開始されると、コモンレール圧は変化の傾向を変えるので、コモンレール圧の計測値は、コモンレールへの燃料の供給量がゼロの状態が続くと仮定した場合のコモンレール圧の仮定値から徐々に乖離する。よって、第２供給開始値演算手段により、この乖離の程度を示す計測値と仮定値との差に基づき、供給開始値を決定すれば、正確に供給開始値を求めることができる。この結果、指令値特性を正確に補正することができる。 [Means of claim 2]
The supply start value learning means of the accumulator fuel injection device according to claim 2 is configured such that when the injector is not injecting and supplying fuel, a command value given to the metering means is zero when the amount of fuel supplied to the common rail is zero. A command value increasing / decreasing means that changes from a value that guarantees that, and when the command value increasing / decreasing means is being executed, a measured value of the fuel pressure of the common rail that is calculated using the rail pressure detection signal, And a second supply start value calculating means for determining a supply start value based on a difference from an assumed value of the fuel pressure of the common rail when it is assumed that the fuel supply amount continues to be zero.
As a result, when the command value increasing / decreasing means is executed and the supply of fuel to the common rail is started, the common rail pressure changes its tendency to change. Gradually deviates from the assumed value of the common rail pressure. Therefore, if the supply start value is determined by the second supply start value calculation means based on the difference between the measured value indicating the degree of deviation and the assumed value, the supply start value can be accurately obtained. As a result, the command value characteristic can be accurately corrected.

〔請求項３の手段〕
請求項３に記載の蓄圧式燃料噴射装置は、コモンレールへの燃料の供給量がゼロではない特定量であるときの指令値を、特定値として学習する特定値学習手段を備え、供給量制御手段は、コモンレールへの燃料の供給量と指令値との相関を示す指令値特性に基づき指令値を算出し、算出された指令値を調量手段に与えることによりコモンレールへの燃料の供給量を制御するとともに、特定値学習手段により学習された特定値、および供給開始値学習手段により学習された供給開始値を用いて指令値特性を補正する。
これにより、コモンレールへの燃料の供給量がゼロではない特定量であるときの指令値（特定値）を学習することができ、さらに、特定値および供給開始値の２つの指令値の学習値により指令値特性を補正することができる。このため、コモンレールへの燃料の供給が開始されるときと、コモンレールへの燃料の供給量が特定量であるときとに基づいて指令値特性を補正することができる。この結果、コモンレールへの燃料の供給量が多い高負荷状態での指令値特性を、より正確に補正することができる。 [Means of claim 3]
The pressure-accumulation fuel injection device according to claim 3 includes specific value learning means for learning, as a specific value, a command value when the supply amount of fuel to the common rail is a specific amount that is not zero. Calculates the command value based on the command value characteristic indicating the correlation between the fuel supply amount to the common rail and the command value, and gives the calculated command value to the metering means to control the fuel supply amount to the common rail At the same time, the command value characteristics are corrected using the specific value learned by the specific value learning means and the supply start value learned by the supply start value learning means.
Thereby, it is possible to learn the command value (specific value) when the fuel supply amount to the common rail is a non-zero specific amount, and further, by learning values of the two command values of the specific value and the supply start value. The command value characteristic can be corrected. Therefore, the command value characteristic can be corrected based on when the supply of fuel to the common rail is started and when the supply amount of fuel to the common rail is a specific amount. As a result, the command value characteristic in a high load state where the amount of fuel supplied to the common rail is large can be corrected more accurately.

最良の形態１の蓄圧式燃料噴射装置は、燃料を蓄圧するコモンレールと、コモンレールへ燃料を供給する燃料供給手段と、コモンレールへ供給される燃料を調量する調量手段と、コモンレールに蓄圧された燃料を内燃機関の気筒に噴射供給するインジェクタと、コモンレールの燃料圧力に応じたレール圧検出信号を出力するコモンレール圧検出手段と、調量手段に与える指令値を変化させることにより、コモンレールへの燃料の供給量を制御する供給量制御手段と、コモンレールへの燃料の供給が開始する時の指令値である供給開始値を学習する供給開始値学習手段とを備え、供給開始値学習手段は、インジェクタが燃料の噴射供給を行っていないときに、指令値を、コモンレールへの燃料の供給量がゼロであることを保証する値から変化させる指令値増減手段と、指令値増減手段が実行されているときに、レール圧検出信号を用いて算出されるコモンレールの燃料圧力の変化率に基づき、供給開始値を決定する第１供給開始値演算手段とを有する。   The pressure accumulation type fuel injection device of the best mode 1 is a common rail for accumulating fuel, a fuel supply means for supplying fuel to the common rail, a metering means for metering fuel supplied to the common rail, and a pressure accumulated in the common rail. An injector for supplying fuel to the cylinder of the internal combustion engine, a common rail pressure detecting means for outputting a rail pressure detection signal corresponding to the fuel pressure of the common rail, and a command value given to the metering means to change the fuel to the common rail. Supply amount control means for controlling the supply amount of fuel, and supply start value learning means for learning a supply start value that is a command value when the supply of fuel to the common rail starts. The supply start value learning means comprises an injector The command value is changed from the value that guarantees that the fuel supply to the common rail is zero when fuel is not being injected. Command value increase / decrease means and a first supply start value for determining a supply start value based on the rate of change of the fuel pressure of the common rail calculated using the rail pressure detection signal when the command value increase / decrease means is executed. Computing means.

最良の形態２の蓄圧式燃料噴射装置の供給開始値学習手段は、インジェクタが燃料の噴射供給を行っていないときに、指令値を、コモンレールへの燃料の供給量がゼロであることを保証する値から変化させる指令値増減手段と、指令値増減手段が実行されているときに、レール圧検出信号を用いて算出されるコモンレールの燃料圧力の計測値と、コモンレールへの燃料の供給量がゼロの状態が続くと仮定した場合のコモンレールの燃料圧力の仮定値との差に基づき、供給開始値を決定する第２供給開始値演算手段とを有する。   The supply start value learning means of the accumulator type fuel injection device of the best mode 2 ensures that the fuel supply amount to the common rail is zero when the injector is not injecting and supplying fuel. When the command value increasing / decreasing means changing from the value and the command value increasing / decreasing means are executed, the measured value of the common rail fuel pressure calculated using the rail pressure detection signal and the amount of fuel supplied to the common rail are zero. And a second supply start value calculating means for determining a supply start value based on a difference from an assumed value of the fuel pressure of the common rail when it is assumed that the above condition continues.

〔実施例１の構成〕
実施例１の蓄圧式燃料噴射装置１（以下、単に燃料噴射装置１とする）の構成を図１ないし図３を用いて説明する。燃料噴射装置１は、例えば、４気筒のディーゼルエンジン（図示せず：以下、単にエンジンと呼ぶ）の各気筒に燃料を噴射供給する装置である。 [Configuration of Example 1]
A configuration of a pressure accumulating fuel injection device 1 (hereinafter simply referred to as a fuel injection device 1) according to the first embodiment will be described with reference to FIGS. The fuel injection device 1 is, for example, a device that injects and supplies fuel to each cylinder of a four-cylinder diesel engine (not shown: hereinafter simply referred to as an engine).

この燃料噴射装置１は、図１に示すように、燃料を蓄圧するコモンレール２と、燃料タンク３から燃料を汲み上げ、汲み上げた燃料を調量するとともに高圧化しコモンレール２へ供給する燃料供給ポンプ４と、各気筒に搭載され、コモンレール２に蓄圧された燃料を気筒に噴射供給するインジェクタ５と、コモンレール２の燃料圧力（コモンレール圧）を検出するコモンレール圧センサ６と、燃料供給ポンプ４やインジェクタ５等を制御する電子制御装置（ＥＣＵ）７とを備える。   As shown in FIG. 1, the fuel injection device 1 includes a common rail 2 for accumulating fuel, a fuel supply pump 4 for pumping fuel from a fuel tank 3, metering the pumped fuel, and increasing the pressure to supply to the common rail 2. The injector 5 mounted on each cylinder and injecting fuel accumulated in the common rail 2 into the cylinder, the common rail pressure sensor 6 for detecting the fuel pressure (common rail pressure) of the common rail 2, the fuel supply pump 4, the injector 5 and the like And an electronic control unit (ECU) 7 for controlling the motor.

コモンレール２は、インジェクタ５に供給する燃料を高圧状態で蓄圧する蓄圧容器である。コモンレール２は、ポンプ配管１１により燃料供給ポンプ４の吐出口と接続され、燃料供給ポンプ４から高圧燃料の供給を受けるとともに、複数のインジェクタ配管１２によりインジェクタ５と接続され、各々のインジェクタ５へ高圧燃料を供給する。また、コモンレール２には、コモンレール圧を限界設定値以下に抑えるためのプレッシャリミッタ１３、コモンレール圧を迅速に目標値まで減圧するための減圧弁１４などが取り付けられている。そして、プレッシャリミッタ１３や減圧弁１４から逃されたリーク燃料はリリーフ配管１５を経て燃料タンク３へ戻される。   The common rail 2 is a pressure accumulation container that accumulates fuel supplied to the injector 5 in a high pressure state. The common rail 2 is connected to the discharge port of the fuel supply pump 4 by a pump pipe 11, receives supply of high-pressure fuel from the fuel supply pump 4, and is connected to the injector 5 by a plurality of injector pipes 12. Supply fuel. Further, the common rail 2 is provided with a pressure limiter 13 for suppressing the common rail pressure below a limit set value, a pressure reducing valve 14 for quickly reducing the common rail pressure to a target value, and the like. The leaked fuel escaped from the pressure limiter 13 and the pressure reducing valve 14 is returned to the fuel tank 3 through the relief pipe 15.

燃料供給ポンプ４は、図２に示すように、燃料タンク３から燃料を汲み上げるフィードポンプ１８（図２では、９０°転回した状態で示されている）、フィードポンプ１８からの供給圧を調節するレギュレータバルブ１９、フィードポンプ１８から供給される燃料を吸入するとともに調量する吸入調量弁２０、吸入調量弁２０から供給される燃料を高圧化してコモンレール２へ供給する高圧ポンプ２１等から構成される。   As shown in FIG. 2, the fuel supply pump 4 adjusts the supply pressure from the feed pump 18 (shown in a state of being rotated 90 ° in FIG. 2) that pumps fuel from the fuel tank 3. A regulator valve 19, a suction metering valve 20 that sucks and measures the fuel supplied from the feed pump 18, a high pressure pump 21 that increases the pressure of the fuel supplied from the suction metering valve 20 and supplies the fuel to the common rail 2, and the like. Is done.

フィードポンプ１８は、カムシャフト２５により回転駆動されるトロコイドポンプである。フィードポンプ１８が駆動されると、燃料タンク３から燃料フィルタ２６を介して燃料が吸引される。吸引された燃料は、燃料入口２７からフィードポンプ１８内へ導かれ、吸入調量弁２０へ供給される。   The feed pump 18 is a trochoid pump that is rotationally driven by a camshaft 25. When the feed pump 18 is driven, fuel is sucked from the fuel tank 3 through the fuel filter 26. The sucked fuel is guided from the fuel inlet 27 into the feed pump 18 and supplied to the intake metering valve 20.

レギュレータバルブ１９は、フィードポンプ１８の供給側と吸引側とを連通する燃料流路２８に配置されている。そして、レギュレータバルブ１９は、フィードポンプ１８の供給圧が所定圧に上昇すると開弁し、フィードポンプ１８の供給圧が所定圧を超えないように調節する。   The regulator valve 19 is disposed in a fuel flow path 28 that connects the supply side and the suction side of the feed pump 18. The regulator valve 19 opens when the supply pressure of the feed pump 18 rises to a predetermined pressure, and adjusts so that the supply pressure of the feed pump 18 does not exceed the predetermined pressure.

吸入調量弁２０は、コモンレール２へ供給される燃料を調量する調量手段である。この吸入調量弁２０は、フィードポンプ１８から高圧ポンプ２１へ燃料を導く供給路２９に配置され、高圧ポンプ２１へ供給される燃料を調量することにより、コモンレール２へ供給される燃料を調量する。吸入調量弁２０は、ＥＣＵ７からの指令により通電量が調節され、通電量に応じた磁気吸引力を発生させるソレノイド３２、磁気吸引され供給路２９の開口面積を調節する弁体３３、弁体３３を磁気吸引力の逆方向に付勢するスプリング３４、および弁体３３を保持する弁ボディ３５等から構成されている。なお、実施例１の吸入調量弁２０は、ソレノイド３２への通電が停止されると供給路２９の開口面積が最大となるノーマリオープン型である。   The intake metering valve 20 is a metering means for metering the fuel supplied to the common rail 2. The intake metering valve 20 is arranged in a supply passage 29 that guides fuel from the feed pump 18 to the high-pressure pump 21, and regulates the fuel supplied to the common rail 2 by metering the fuel supplied to the high-pressure pump 21. To measure. The suction metering valve 20 is adjusted in accordance with a command from the ECU 7 so that the energization amount is adjusted, a solenoid 32 that generates a magnetic attraction force corresponding to the energization amount, a valve body 33 that is magnetically attracted and adjusts the opening area of the supply passage 29, It comprises a spring 34 that urges 33 in the direction opposite to the magnetic attractive force, a valve body 35 that holds the valve body 33, and the like. The suction metering valve 20 of the first embodiment is a normally open type in which the opening area of the supply passage 29 is maximized when the energization to the solenoid 32 is stopped.

高圧ポンプ２１は、吸入調量弁２０から供給された燃料を高圧に圧縮してコモンレール２へ供給する燃料供給手段である。高圧ポンプ２１は、カムシャフト２５により往復駆動されるプランジャ３８、プランジャ３８の往復動により容積を変える加圧室３９に燃料を供給する吸入弁４０、加圧室３９で圧縮された燃料をコモンレール２へ向けて供給する吐出弁４１等から構成されている。   The high-pressure pump 21 is a fuel supply unit that compresses the fuel supplied from the intake metering valve 20 to a high pressure and supplies the compressed fuel to the common rail 2. The high-pressure pump 21 includes a plunger 38 that is reciprocated by the camshaft 25, a suction valve 40 that supplies fuel to the pressurization chamber 39 that changes its volume by the reciprocation of the plunger 38, and fuel that is compressed in the pressurization chamber 39. It is comprised from the discharge valve 41 etc. which supply toward.

プランジャ３８は、カムシャフト２５のエキセンカム４２の周囲に装着されたカムリング４３に、スプリング４４によって押し付けられている。そして、カムシャフト２５が回転すると、カムリング４３の偏心動作に伴いプランジャ３８が往復動する。これにより、プランジャ３８が下降して加圧室３９の燃料圧力が低下すると、吐出弁４１が閉弁するとともに、吸入弁４０が開弁して吸入調量弁２０で調量された燃料が加圧室３９に吸入される。逆に、プランジャ３８が上昇して加圧室３９の燃料圧力が上昇すると、吸入弁４０が閉弁する。そして、加圧室３９の燃料圧力が所定圧力に達すると、吐出弁４１が開弁して、加圧室３９で加圧された高圧燃料がポンプ配管１１を介してコモンレール２へ供給される。   The plunger 38 is pressed by a spring 44 against a cam ring 43 mounted around the eccentric cam 42 of the camshaft 25. When the camshaft 25 rotates, the plunger 38 reciprocates with the eccentric operation of the cam ring 43. As a result, when the plunger 38 is lowered and the fuel pressure in the pressurizing chamber 39 is lowered, the discharge valve 41 is closed and the intake valve 40 is opened and the fuel metered by the suction metering valve 20 is added. It is sucked into the pressure chamber 39. Conversely, when the plunger 38 is raised and the fuel pressure in the pressurizing chamber 39 is raised, the suction valve 40 is closed. When the fuel pressure in the pressurizing chamber 39 reaches a predetermined pressure, the discharge valve 41 is opened, and the high-pressure fuel pressurized in the pressurizing chamber 39 is supplied to the common rail 2 via the pump pipe 11.

インジェクタ５は、コモンレール２から供給された高圧燃料を気筒に噴射供給する燃料噴射ノズル、およびこの燃料噴射ノズルに収容されたニードルをＥＣＵ７からの指令に応じて駆動する電磁弁等から構成される。インジェクタ５は、コモンレール２より分岐する複数のインジェクタ配管１２の下流端に接続され、コモンレール２から高圧燃料の供給を受ける。また、インジェクタ５からのリーク燃料は、リリーフ配管１５を経て燃料タンク３へ戻される。   The injector 5 includes a fuel injection nozzle that injects high-pressure fuel supplied from the common rail 2 into the cylinder, and an electromagnetic valve that drives a needle housed in the fuel injection nozzle in response to a command from the ECU 7. The injector 5 is connected to the downstream ends of a plurality of injector pipes 12 branched from the common rail 2 and receives supply of high-pressure fuel from the common rail 2. Further, the leaked fuel from the injector 5 is returned to the fuel tank 3 through the relief pipe 15.

コモンレール圧センサ６は、コモンレール圧を検出するとともに、コモンレール圧に応じたレール圧検出信号を出力するコモンレール圧検出手段である。   The common rail pressure sensor 6 is a common rail pressure detection unit that detects a common rail pressure and outputs a rail pressure detection signal corresponding to the common rail pressure.

ＥＣＵ７は、制御処理、演算処理を行うＣＰＵ、各種プログラムおよびデータを保存する記憶装置（ＲＯＭ、スタンバイＲＡＭ、ＥＥＰＲＯＭ、ＲＡＭ等のメモリ）、入力装置、出力装置を有するマイクロコンピュータである。そして、ＥＣＵ７は、コモンレール圧センサ６やその他の各種センサ４８から入力される検出信号に基づいて各種の演算処理を行い、燃料供給ポンプ４やインジェクタ５等を駆動制御するための指令信号を合成して出力する。   The ECU 7 is a microcomputer having a CPU for performing control processing and arithmetic processing, a storage device for storing various programs and data (memory such as ROM, standby RAM, EEPROM, RAM, etc.), an input device, and an output device. The ECU 7 performs various arithmetic processes based on detection signals input from the common rail pressure sensor 6 and other various sensors 48, and synthesizes command signals for driving and controlling the fuel supply pump 4, the injector 5, and the like. Output.

例えば、ＥＣＵ７は、エンジンの運転状態（例えば、エンジン回転数）に応じて、コモンレール圧を調節するため、燃料供給ポンプ４によるコモンレール２への燃料の供給量Ｑを制御する。すなわち、ＥＣＵ７は、各種検出信号に基づきコモンレール圧の目標値を算出するとともに、この目標値を維持するのに必要とする供給量Ｑを算出する。そして、ＥＣＵ７は、この供給量Ｑの算出値に応じて、吸入調量弁２０へ与える指令値としてソレノイド３２の通電量（駆動電流値Ｉｓｃｖ）を算出するとともに、駆動電流値Ｉｓｃｖに応じた指令信号を合成して出力する。これにより、ソレノイド３２に駆動電流値Ｉｓｃｖに相当する通電が行われ、供給路２９の開口面積が供給量Ｑに応じた大きさに調節される。   For example, the ECU 7 controls the fuel supply amount Q to the common rail 2 by the fuel supply pump 4 in order to adjust the common rail pressure in accordance with the operating state of the engine (for example, the engine speed). That is, the ECU 7 calculates the target value of the common rail pressure based on various detection signals, and calculates the supply amount Q required to maintain this target value. Then, the ECU 7 calculates the energization amount (drive current value Iscv) of the solenoid 32 as a command value to be given to the intake metering valve 20 according to the calculated value of the supply amount Q, and the command according to the drive current value Iscv. Combine and output signals. As a result, the solenoid 32 is energized corresponding to the drive current value Iscv, and the opening area of the supply path 29 is adjusted to a size corresponding to the supply amount Q.

このように、ＥＣＵ７は、調量手段としての吸入調量弁２０に与える指令値（駆動電流値Ｉｓｃｖ）を変化させることにより、コモンレール２への燃料の供給量Ｑを制御する供給量制御手段として機能する。   In this way, the ECU 7 serves as a supply amount control means for controlling the fuel supply amount Q to the common rail 2 by changing the command value (drive current value Iscv) given to the intake metering valve 20 as the metering means. Function.

〔実施例１の特徴〕
実施例１の燃料噴射装置１の特徴を、図３および図４を用いて説明する。
実施例１のＥＣＵ７は、コモンレール２への燃料の供給を開始する時の指令値（駆動電流値Ｉｓｃｖ）である供給開始値（供給開始駆動電流値Ｉｓｃｖ０）を学習する供給開始値学習手段として機能する。供給開始値学習手段は、インジェクタ５が燃料の噴射供給を行っていないときに、駆動電流値Ｉｓｃｖを、供給量Ｑがゼロであることを保証する値から変化させる指令値増減手段、および、指令値増減手段が実行されているときに、レール圧検出信号を用いて算出されるコモンレール圧の変化率ΔＰに基づき、供給開始駆動電流値Ｉｓｃｖ０を決定する第１供給開始値演算手段の機能を有する。 [Features of Example 1]
Features of the fuel injection device 1 according to the first embodiment will be described with reference to FIGS. 3 and 4.
The ECU 7 according to the first embodiment functions as a supply start value learning unit that learns a supply start value (supply start drive current value Iscv0) that is a command value (drive current value Iscv) when the supply of fuel to the common rail 2 is started. To do. The supply start value learning means includes a command value increase / decrease means for changing the drive current value Iscv from a value that guarantees that the supply amount Q is zero when the injector 5 is not injecting and supplying fuel. When the value increasing / decreasing means is executed, it has a function of a first supply start value calculating means for determining the supply start drive current value Iscv0 based on the change rate ΔP of the common rail pressure calculated using the rail pressure detection signal. .

指令値増減手段は、ＥＣＵ７がインジェクタ５による燃料の噴射供給が行われていないと判断したときに実行される。実施例１の吸入調量弁２０はノーマリオープン型であるので、指令値増減手段は、供給量Ｑがゼロであることを保証する値（例えば、図３（ａ）におけるゼロ供給量保証値Ｉｓｃｖ０′）から駆動電流値Ｉｓｃｖが漸減するように設定されている。   The command value increasing / decreasing means is executed when the ECU 7 determines that fuel injection from the injector 5 is not being performed. Since the intake metering valve 20 of the first embodiment is a normally open type, the command value increasing / decreasing means is a value that guarantees that the supply amount Q is zero (for example, the zero supply amount guarantee value in FIG. 3A). The drive current value Iscv is set to gradually decrease from Iscv0 ′).

第１供給開始値演算手段は、指令値増減手段が実行され駆動電流値Ｉｓｃｖが漸減しているときに実行され、この実行に伴いコモンレール圧の変化率ΔＰが算出される。なお、コモンレール圧の変化率ΔＰは、コモンレール圧の計測値Ｐの差分に応じた値であり、コモンレール圧の計測周期毎に、変化率ΔＰも算出される。   The first supply start value calculating means is executed when the command value increasing / decreasing means is executed and the drive current value Iscv is gradually decreasing, and the change rate ΔP of the common rail pressure is calculated along with this execution. The change rate ΔP of the common rail pressure is a value corresponding to the difference in the measured value P of the common rail pressure, and the change rate ΔP is also calculated for each measurement period of the common rail pressure.

そして、図４に示すように、例えば時間ｔｏにおいて、供給路２９が開口しコモンレール２への燃料の供給が開始されると、コモンレール圧の計測値Ｐはインジェクタ５からのリーク量のみに応じて減少するのを止める。そして、コモンレール圧の変化率ΔＰは、時間ｔｏ以前よりも増加率が大きくなる。このように時間ｔｏにおいて、コモンレール圧の計測値Ｐ、およびコモンレール圧の変化率ΔＰは、明らかに変化の傾向を変えるので、時間ｔｏにおける駆動電流値Ｉｓｃｖの値が供給開始駆動電流値Ｉｓｃｖ０として学習される。なお、コモンレール圧の計測値Ｐが減少しているときの変化率ΔＰは負の値であり、コモンレール圧の計測値Ｐが増加しているときの変化率ΔＰは正の値である。   Then, as shown in FIG. 4, for example, at time to, when the supply path 29 is opened and the supply of fuel to the common rail 2 is started, the measured value P of the common rail pressure depends only on the leak amount from the injector 5. Stop decreasing. The rate of change ΔP of the common rail pressure increases more than before time to. Thus, at time to, the measured value P of the common rail pressure and the change rate ΔP of the common rail pressure clearly change the tendency of change, so that the value of the drive current value Iscv at time to is learned as the supply start drive current value Iscv0. Is done. Note that the rate of change ΔP when the measured value P of the common rail pressure decreases is a negative value, and the rate of change ΔP when the measured value P of the common rail pressure increases is a positive value.

そして、図３（ａ）に示すように、新たな供給開始駆動電流値Ｉｓｃｖ０の学習値を横軸（駆動電流値Ｉｓｃｖの軸）に配置する。そして、この座標（Ｉｓｃｖ０、０）を通るように、各種回転数に相当する勾配の相関線を描くことにより、コモンレール２への燃料の供給量Ｑと指令値（駆動電流値Ｉｓｃｖ）との相関を示す指令値特性が補正される。   Then, as shown in FIG. 3A, the learning value of the new supply start drive current value Iscv0 is arranged on the horizontal axis (axis of the drive current value Iscv). The correlation between the fuel supply amount Q to the common rail 2 and the command value (driving current value Iscv) is drawn by drawing a correlation line having a gradient corresponding to various rotation speeds so as to pass through the coordinates (Iscv0, 0). The command value characteristic indicating is corrected.

〔実施例１の効果〕
実施例１の燃料噴射装置では、インジェクタ５が燃料の噴射供給を行っていないときに、駆動電流値Ｉｓｃｖを、ゼロ供給量保証値Ｉｓｃｖ０′から減少させ、この減少が行われているときのコモンレール圧の変化率ΔＰの推移に基づき、供給開始駆動電流値Ｉｓｃｖ０を決定する。
コモンレール２への燃料の供給量Ｑをゼロにすると、コモンレール圧は、インジェクタ５からのリーク量のみに応じて低下し、やがて、インジェクタ５からのリークがなくなると、コモンレール圧は一定値に安定する（図４（ａ）の仮定値Ｐ′の推移を参照）。
そこで、インジェクタ５が燃料の噴射供給を行っていない状態で、駆動電流値Ｉｓｃｖを、ゼロ供給量保証値Ｉｓｃｖ０′に変更し、その後、駆動電流値Ｉｓｃｖを減少させる。これにより、コモンレール２への燃料の供給が開始されると、図４に示すようにコモンレール圧の変化の傾向は、インジェクタ５からのリーク量のみに応じて低下する状態から明確に変わる。よって、コモンレール圧の変化の傾向を示すコモンレール圧の変化率ΔＰを用いれば、正確に供給開始駆動電流値Ｉｓｃｖ０を求めることができる。この結果、指令値特性を正確に補正することができる。 [Effect of Example 1]
In the fuel injection device of the first embodiment, when the injector 5 is not injecting and supplying fuel, the drive current value Iscv is decreased from the zero supply amount guarantee value Iscv0 ′, and the common rail when the decrease is performed is performed. Based on the transition of the pressure change rate ΔP, the supply start drive current value Iscv0 is determined.
When the fuel supply amount Q to the common rail 2 is set to zero, the common rail pressure decreases according to only the amount of leakage from the injector 5, and eventually the common rail pressure stabilizes to a constant value when the leakage from the injector 5 disappears. (See the transition of the assumed value P ′ in FIG. 4A).
Therefore, the drive current value Iscv is changed to the zero supply amount guarantee value Iscv0 ′ in a state where the injector 5 is not injecting and supplying fuel, and then the drive current value Iscv is decreased. As a result, when the supply of fuel to the common rail 2 is started, the tendency of the change in the common rail pressure clearly changes from a state in which the common rail pressure changes according to only the leak amount from the injector 5 as shown in FIG. Therefore, the supply start drive current value Iscv0 can be accurately obtained by using the change rate ΔP of the common rail pressure indicating the tendency of the change in the common rail pressure. As a result, the command value characteristic can be accurately corrected.

〔実施例２の特徴〕
実施例２の燃料噴射装置１の特徴を、図４を用いて説明する。
実施例２の供給開始値学習手段は、インジェクタ５が燃料の噴射供給を行っていないときに、駆動電流値Ｉｓｃｖを、供給量Ｑがゼロであることを保証する値から変化させる指令値増減手段、および、指令値増減手段が実行されているときに、レール圧検出信号を用いて算出されるコモンレール圧の計測値Ｐと、コモンレール２への燃料の供給量Ｑがゼロの状態が続くと仮定した場合のコモンレール圧の仮定値Ｐ′との差に基づき、供給開始駆動電流値Ｉｓｃｖ０を決定する第２供給開始値演算手段の機能を有する。 [Features of Example 2]
Features of the fuel injection device 1 according to the second embodiment will be described with reference to FIG.
The supply start value learning unit according to the second embodiment is a command value increase / decrease unit that changes the drive current value Iscv from a value that guarantees that the supply amount Q is zero when the injector 5 is not injecting and supplying fuel. Assuming that the measured value P of the common rail pressure calculated using the rail pressure detection signal and the fuel supply amount Q to the common rail 2 continue to be zero when the command value increasing / decreasing means is being executed. The second supply start value calculation means for determining the supply start drive current value Iscv0 based on the difference from the assumed value P ′ of the common rail pressure in this case.

第２供給開始値演算手段は、指令値増減手段が実行され駆動電流値Ｉｓｃｖが漸減しているときに実行され、この実行に伴いコモンレール圧の仮定値Ｐ′、およびコモンレール圧の計測値Ｐとコモンレール圧の仮定値Ｐ′との差が算出される。なお、仮定値Ｐ′、および計測値Ｐと仮定値Ｐ′との差は、コモンレール圧の計測周期毎に算出される。   The second supply start value calculating means is executed when the command value increasing / decreasing means is executed and the drive current value Iscv is gradually decreasing. Along with this execution, the assumed value P ′ of the common rail pressure and the measured value P of the common rail pressure are A difference from the assumed value P ′ of the common rail pressure is calculated. The assumed value P ′ and the difference between the measured value P and the assumed value P ′ are calculated for each measurement period of the common rail pressure.

そして、図４に示すように、例えば時間ｔｏにおいて、供給路２９が開口しコモンレール２への燃料の供給が開始されると、コモンレール圧の計測値Ｐはインジェクタ５からのリーク量のみに応じて減少するのを止める。そして、計測値Ｐと仮定値Ｐ′とは、時間ｔｏを経過すると徐々に乖離し、計測値Ｐと仮定値Ｐ′との差は拡大する。このように時間ｔｏを経過すると、計測値Ｐと仮定値Ｐ′との差は、明らかに拡大するので、時間ｔｏにおける駆動電流値Ｉｓｃｖの値が供給開始駆動電流値Ｉｓｃｖ０として学習される。なお、時間ｔｏ以前の、計測値Ｐと仮定値Ｐ′との差は、ほぼゼロである。   Then, as shown in FIG. 4, for example, at time to, when the supply path 29 is opened and the supply of fuel to the common rail 2 is started, the measured value P of the common rail pressure depends only on the leak amount from the injector 5. Stop decreasing. Then, the measured value P and the assumed value P ′ gradually deviate when the time to elapses, and the difference between the measured value P and the assumed value P ′ increases. Thus, when the time to elapses, the difference between the measured value P and the assumed value P ′ clearly increases, so that the value of the drive current value Iscv at the time to is learned as the supply start drive current value Iscv0. Note that the difference between the measured value P and the assumed value P ′ before time to is almost zero.

〔実施例２の効果〕
実施例２の燃料噴射装置１では、インジェクタ５が燃料の噴射供給を行っていないときに、駆動電流値Ｉｓｃｖを、ゼロ供給量保証値Ｉｓｃｖ０′から減少させ、この減少が行われているときのコモンレール圧の計測値Ｐとコモンレール圧の仮定値Ｐ′との差の推移に基づき、供給開始駆動電流値Ｉｓｃｖ０を決定する。
これにより、駆動電流値Ｉｓｃｖが減少しているときに、コモンレール２への燃料の供給が開始されると、コモンレール圧の計測値Ｐは、コモンレール圧の仮定値Ｐ′から徐々に乖離する。よって、この乖離の程度を示す計測値Ｐと仮定値Ｐ′との差を用いれば正確に供給開始駆動電流値Ｉｓｃｖ０を求めることができる。この結果、指令値特性を正確に補正することができる。 [Effect of Example 2]
In the fuel injection device 1 according to the second embodiment, when the injector 5 is not injecting and supplying fuel, the drive current value Iscv is decreased from the zero supply amount guarantee value Iscv0 ′, and this decrease is performed. Based on the transition of the difference between the measured value P of the common rail pressure and the assumed value P ′ of the common rail pressure, the supply start drive current value Iscv0 is determined.
Thus, when the supply of fuel to the common rail 2 is started while the drive current value Iscv is decreasing, the measured value P of the common rail pressure gradually deviates from the assumed value P ′ of the common rail pressure. Therefore, the supply start drive current value Iscv0 can be accurately obtained by using the difference between the measured value P indicating the degree of deviation and the assumed value P ′. As a result, the command value characteristic can be accurately corrected.

〔変形例〕
本実施例では、供給開始値である供給開始駆動電流値Ｉｓｃｖ０の学習値を用いて指令値特性を補正したが、供給開始値の学習値以外に、供給量Ｑがゼロではない特定量であるときの駆動電流値Ｉｓｃｖの学習値を、指令値特性の補正に用いてもよい。 [Modification]
In this embodiment, the command value characteristic is corrected using the learned value of the supply start drive current value Iscv0 that is the supply start value. However, in addition to the learned value of the supply start value, the supply amount Q is a specific amount that is not zero. The learned value of the driving current value Iscv may be used for correcting the command value characteristic.

この場合、ＥＣＵ７は、供給量Ｑが特定量であるときの指令値（駆動電流値Ｉｓｃｖ）を、特定値として学習する特定値学習手段としての機能を有し、特定値学習手段により学習された特定値、および供給開始値学習手段により学習された供給開始値（供給開始駆動電流値Ｉｓｃｖ０）を用いて指令値特性を補正する。   In this case, the ECU 7 has a function as a specific value learning unit that learns a command value (drive current value Iscv) when the supply amount Q is a specific amount as a specific value, and has been learned by the specific value learning unit. The command value characteristic is corrected using the specific value and the supply start value (supply start drive current value Iscv0) learned by the supply start value learning means.

なお、特定量には、例えば、アイドリング時の供給量Ｑであるｑｉ＋Ｌｉを採用することができる。また、この場合、特定値はアイドル駆動電流値Ｉｓｃｖｉである。そして、供給開始値学習手段により供給開始駆動電流値Ｉｓｃｖ０が前回値から今回値に学習更新され、特定値学習手段によりアイドル駆動電流値Ｉｓｃｖｉが前回値から今回値に学習更新される。これにより、指令値特性をなす相関線の内、アイドル回転数に相当する勾配を有する相関線は、図５に示すように補正される。そして、これに基づき、他のエンジン回転数に相当する勾配を有する相関線も補正される。この結果、供給量Ｑが多い高負荷状態での指令値特性を、より正確に補正することができる。   As the specific amount, for example, qi + Li that is the supply amount Q at the time of idling can be adopted. In this case, the specific value is the idle drive current value Isvvi. Then, the supply start drive current value Iscv0 is learned and updated from the previous value to the current value by the supply start value learning means, and the idle drive current value Iscv is learned and updated from the previous value to the current value by the specific value learning means. As a result, the correlation line having a gradient corresponding to the idling speed among the correlation lines forming the command value characteristics is corrected as shown in FIG. Based on this, correlation lines having gradients corresponding to other engine speeds are also corrected. As a result, the command value characteristic in a high load state where the supply amount Q is large can be corrected more accurately.

本実施例の吸入調量弁２０はノーマリオープン型であったが、ソレノイド３２への通電が停止されると、供給路２９が閉鎖されるノーマリクローズ型であっても、本実施例と同様の効果を得ることができる。   Although the suction metering valve 20 of the present embodiment is a normally open type, even if it is a normally closed type in which the supply passage 29 is closed when the energization to the solenoid 32 is stopped, Similar effects can be obtained.

燃料噴射装置の概略図である（実施例）。It is the schematic of a fuel-injection apparatus (Example). 燃料供給ポンプの断面図である（実施例）。It is sectional drawing of a fuel supply pump (Example). （ａ）は、コモンレールへの燃料の供給量と吸入調量弁に与えられる駆動電流値との相関図であり、（ｂ）は、供給開始駆動電流値の学習位置を示す説明図である（実施例）。(A) is a correlation diagram between the supply amount of fuel to the common rail and the drive current value given to the intake metering valve, and (b) is an explanatory diagram showing the learning position of the supply start drive current value ( Example). （ａ）は、コモンレール圧の時間推移を示すトレンド図であり、（ｂ）は、コモンレール圧の変化率の時間推移を示すトレンド図であり、（ｃ）は、駆動電流値の時間推移を示すトレンド図である（実施例）。(A) is a trend diagram showing the time transition of the common rail pressure, (b) is a trend diagram showing the time transition of the change rate of the common rail pressure, and (c) shows the time transition of the drive current value. It is a trend figure (example). コモンレールへの燃料の供給量と吸入調量弁に与えられる駆動電流値との相関図である（変形例）。FIG. 6 is a correlation diagram between the amount of fuel supplied to the common rail and the drive current value applied to the intake metering valve (modified example). （ａ）は、コモンレールへの燃料の供給量と吸入調量弁に与えられる駆動電流値との相関図であり、（ｂ）は、供給開始駆動電流値の学習位置を示す説明図である（従来例）。(A) is a correlation diagram between the supply amount of fuel to the common rail and the drive current value given to the intake metering valve, and (b) is an explanatory diagram showing the learning position of the supply start drive current value ( Conventional example).

符号の説明Explanation of symbols

１ 燃料噴射装置
２ コモンレール
５ インジェクタ
６ コモンレール圧センサ（コモンレール圧検出手段）
７ ＥＣＵ（供給量制御手段、供給開始値学習手段、指令値増減手段、第１供給開始値演算手段、第２供給開始値演算手段、特定値学習手段）
２０ 吸入調量弁（調量手段）
２１ 高圧ポンプ（燃料供給手段）
Ｑ 供給量
ｑｉ＋Ｌｉ 特定量
Ｉｓｃｖ 駆動電流値（指令値）
Ｉｓｃｖ０ 供給開始駆動電流値（供給開始値）
Ｉｓｃｖｉ アイドル駆動電流値（特定値）
ΔＰ コモンレール圧の変化率（コモンレールの燃料圧力の変化率）
Ｉｓｃｖ０′ ゼロ供給量保証値（コモンレールへの燃料の供給量がゼロであることを保証する値）
Ｐ コモンレール圧の計測値（コモンレールの燃料圧力の計測値）
Ｐ′ コモンレール圧の仮定値（コモンレールの燃料圧力の仮定値） DESCRIPTION OF SYMBOLS 1 Fuel injection apparatus 2 Common rail 5 Injector 6 Common rail pressure sensor (common rail pressure detection means)
7 ECU (supply amount control means, supply start value learning means, command value increase / decrease means, first supply start value calculation means, second supply start value calculation means, specific value learning means)
20 Inhalation metering valve (measuring means)
21 High-pressure pump (fuel supply means)
Q Supply amount qi + Li Specific amount Iscv Drive current value (command value)
Iscv0 supply start drive current value (supply start value)
Iscvi idle drive current value (specific value)
ΔP Change rate of common rail pressure (Change rate of fuel pressure of common rail)
Iscv0 'Zero supply guarantee value (value that guarantees that the fuel supply to the common rail is zero)
P Measured value of common rail pressure (measured value of fuel pressure of common rail)
P 'Assumed value of common rail pressure (assumed value of fuel pressure of common rail)

Claims (3)

燃料を蓄圧するコモンレールと、
このコモンレールへ燃料を供給する燃料供給手段と、
前記コモンレールへ供給される燃料を調量する調量手段と、
前記コモンレールに蓄圧された燃料を内燃機関の気筒に噴射供給するインジェクタと、
前記コモンレールの燃料圧力に応じたレール圧検出信号を出力するコモンレール圧検出手段と、
前記調量手段に与える指令値を変化させることにより、前記コモンレールへの燃料の供給量を制御する供給量制御手段と、
前記コモンレールへの燃料の供給が開始する時の指令値である供給開始値を学習する供給開始値学習手段とを備え、
前記供給開始値学習手段は、
前記インジェクタが燃料の噴射供給を行っていないときに、前記指令値を、前記コモンレールへの燃料の供給量がゼロであることを保証する値から変化させる指令値増減手段と、
この指令値増減手段が実行されているときに、前記レール圧検出信号を用いて算出される前記コモンレールの燃料圧力の変化率に基づき、前記供給開始値を決定する第１供給開始値演算手段と
を有することを特徴とする蓄圧式燃料噴射装置。 A common rail that accumulates fuel,
Fuel supply means for supplying fuel to the common rail;
Metering means for metering fuel supplied to the common rail;
An injector that injects fuel accumulated in the common rail into a cylinder of an internal combustion engine;
Common rail pressure detection means for outputting a rail pressure detection signal corresponding to the fuel pressure of the common rail;
A supply amount control means for controlling a fuel supply amount to the common rail by changing a command value given to the metering means;
Supply start value learning means for learning a supply start value that is a command value when the supply of fuel to the common rail starts;
The supply start value learning means includes
Command value increasing / decreasing means for changing the command value from a value that guarantees that the amount of fuel supplied to the common rail is zero when the injector is not supplying fuel;
First supply start value calculating means for determining the supply start value based on a rate of change of the fuel pressure of the common rail calculated using the rail pressure detection signal when the command value increasing / decreasing means is executed; A pressure-accumulating fuel injection device characterized by comprising: 燃料を蓄圧するコモンレールと、
このコモンレールへ燃料を供給する燃料供給手段と、
前記コモンレールへ供給される燃料を調量する調量手段と、
前記コモンレールに蓄圧された燃料を内燃機関の気筒に噴射供給するインジェクタと、
前記コモンレールの燃料圧力に応じたレール圧検出信号を出力するコモンレール圧検出手段と、
前記調量手段に与える指令値を変化させることにより、前記コモンレールへの燃料の供給量を制御する供給量制御手段と、
前記コモンレールへの燃料の供給が開始する時の指令値である供給開始値を学習する供給開始値学習手段とを備え、
前記供給開始値学習手段は、
前記インジェクタが燃料の噴射供給を行っていないときに、前記指令値を、前記コモンレールへの燃料の供給量がゼロであることを保証する値から変化させる指令値増減手段と、
この指令値増減手段が実行されているときに、前記レール圧検出信号を用いて算出される前記コモンレールの燃料圧力の計測値と、前記コモンレールへの燃料の供給量がゼロの状態が続くと仮定した場合の前記コモンレールの燃料圧力の仮定値との差に基づき、前記供給開始値を決定する第２供給開始値演算手段と
を有することを特徴とする蓄圧式燃料噴射装置。 A common rail that accumulates fuel,
Fuel supply means for supplying fuel to the common rail;
Metering means for metering fuel supplied to the common rail;
An injector that injects fuel accumulated in the common rail into a cylinder of an internal combustion engine;
Common rail pressure detection means for outputting a rail pressure detection signal corresponding to the fuel pressure of the common rail;
A supply amount control means for controlling a fuel supply amount to the common rail by changing a command value given to the metering means;
Supply start value learning means for learning a supply start value that is a command value when the supply of fuel to the common rail starts;
The supply start value learning means includes
Command value increasing / decreasing means for changing the command value from a value that guarantees that the amount of fuel supplied to the common rail is zero when the injector is not supplying fuel;
It is assumed that when the command value increasing / decreasing means is executed, the measured value of the fuel pressure of the common rail calculated using the rail pressure detection signal and the fuel supply amount to the common rail continue to be zero. And a second supply start value calculating means for determining the supply start value based on a difference from an assumed value of the fuel pressure of the common rail in the case of the pressure accumulation type fuel injection device. 請求項１または請求項２に記載の蓄圧式燃料噴射装置において、
前記コモンレールへの燃料の供給量がゼロではない特定量であるときの指令値を、特定値として学習する特定値学習手段を備え、
前記供給量制御手段は、
前記コモンレールへの燃料の供給量と前記指令値との相関を示す指令値特性に基づき前記指令値を算出し、この算出された指令値を前記調量手段に与えることにより前記コモンレールへの燃料の供給量を制御するとともに、
前記特定値学習手段により学習された前記特定値、および前記供給開始値学習手段により学習された前記供給開始値を用いて前記指令値特性を補正することを特徴とする蓄圧式燃料噴射装置。 In the pressure accumulation type fuel injection device according to claim 1 or 2,
A specific value learning means for learning, as a specific value, a command value when the fuel supply amount to the common rail is a specific amount that is not zero;
The supply amount control means includes:
The command value is calculated on the basis of a command value characteristic indicating a correlation between the fuel supply amount to the common rail and the command value, and the calculated command value is supplied to the metering means to thereby provide the fuel to the common rail. While controlling the supply amount,
The accumulator fuel injection apparatus, wherein the command value characteristic is corrected using the specific value learned by the specific value learning means and the supply start value learned by the supply start value learning means.
JP2004258804A 2004-09-06 2004-09-06 Accumulated fuel injection system Expired - Fee Related JP4329653B2 (en)

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JP2014005769A (en) * 2012-06-22 2014-01-16 Denso Corp Abnormality diagnostic device
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Families Citing this family (2)

* Cited by examiner, † Cited by third party
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EP2128416A1 (en) 2008-05-28 2009-12-02 GM Global Technology Operations, Inc. A method and system for controlling a high pressure pump, particularly for a diesel engine fuel injection system
US9353699B2 (en) 2014-03-31 2016-05-31 Ford Global Technologies, Llc Rapid zero flow lubrication methods for a high pressure pump

Family Cites Families (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP4240673B2 (en) * 1999-09-09 2009-03-18 株式会社デンソー Fuel injection device
US6986646B2 (en) * 2002-04-12 2006-01-17 Caterpillar Inc. Electronic trim for a variable delivery pump in a hydraulic system for an engine
JP4042057B2 (en) * 2003-11-04 2008-02-06 株式会社デンソー Valve opening adjustment device and common rail fuel injection device
DE102004006694A1 (en) * 2004-01-14 2005-08-18 Robert Bosch Gmbh Operating internal combustion engine with injection system involves determining individual characteristic representing real behavior of metering unit during operation of internal combustion engine for controlling metering unit

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JP2009085084A (en) * 2007-09-28 2009-04-23 Denso Corp Fuel supply quantity estimating device and fuel injection system
JP4492664B2 (en) * 2007-09-28 2010-06-30 株式会社デンソー Fuel supply amount estimation device and fuel pressure injection system
US8100112B2 (en) 2007-09-28 2012-01-24 Denso Corporation Fuel-supply quantity estimating apparatus and fuel injection system
JP2014005769A (en) * 2012-06-22 2014-01-16 Denso Corp Abnormality diagnostic device
CN115142976A (en) * 2022-07-07 2022-10-04 潍柴动力股份有限公司 Method and device for determining zero-oil calibration time
CN115142976B (en) * 2022-07-07 2024-05-17 潍柴动力股份有限公司 Method and device for determining zero oil quantity calibration time

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