JP3840356B2

JP3840356B2 - Engine fuel supply system

Info

Publication number: JP3840356B2
Application number: JP2000012633A
Authority: JP
Inventors: 正寛明田; 保生藤井; 敏夫中平; 一山
Original assignee: Kubota Corp
Current assignee: Kubota Corp
Priority date: 1999-08-03
Filing date: 2000-01-21
Publication date: 2006-11-01
Anticipated expiration: 2020-01-21
Also published as: JP2001107791A

Description

【０００１】
【発明の属する技術分野】
本発明は、エンジンの燃料供給装置に関し、詳しくは、電子ガバナとメカニカルガバナの両方を備えたものに関する。
【０００２】
【従来の技術】
従来、電子ガバナとメカニカルガバナとを備え、電子ガバナによる電子制御と、メカニカルガバナによるメカ制御とを行う、エンジンの燃料供給装置として、電子単独制御モードとメカ単独制御モードとを切り替えて使用するものが知られている。
【０００３】
この従来技術の場合、電子単独制御モードでは電子ガバナのみで、メカ単独制御モードではメカニカルガバナのみで、それぞれ調速と最大燃料供給量の制限を行う。
【０００４】
【発明が解決しようとする課題】
上記従来技術には、次の問題がある。
電子単独制御モードでは、電子ガバナで電子制御の最大燃料供給量の制限を行う必要があるため、かかる制限機能を備えた電子ガバナを用いる必要があり、電子ガバナのコストが高くなる。また、かかる制限を考慮した電子ガバナの調整が必要となり、その調整に手間がかかる。
【０００５】
本発明の課題は、上記問題点を解決できる、エンジンの燃料調量装置を提供することにある。
【０００６】
【課題を解決するための手段】
請求項１の発明の構成は、次の通りである。
図１または図１０に示すように、電子ガバナ１とメカニカルガバナ２とを備え、燃料調量部３の調量領域のうち、エンジン始動領域７を除く領域での電子ガバナ１による電子制御の最大燃料供給量をメカニカルガバナ２で制限するようにし、
【０００７】
図１または図１０に示すように、速度設定手段１８の速度設定で、電子ガバナ１による電子制御特性とメカニカルガバナ２によるメカ制御特性とを設定することにより、図２に示すように、所定の基準負荷Ｌ５の時に、燃料調量手段３が上記電子制御の最大燃料供給位置４に位置するようにし、
【０００８】
この所定の基準負荷Ｌ５よりも低い負荷Ｌ４〜Ｌ１での電子制御の整定回転速度ＮＸが、同一負荷Ｌ４〜Ｌ１でのメカ制御の整定回転速度ｎ４〜ｎ１よりもそれぞれ低くなるようにし、エンジン運転中、上記基準負荷Ｌ５よりも低い負荷Ｌ４〜Ｌ１では、電子ガバナ１がエンジン回転速度Ｎを電子制御の整定回転速度ＮＸに整定するようにした、ことを特徴とするエンジンの燃料供給装置。
【０００９】
請求項７の発明の構成は、次の通りである。
図１または図１０に示すように、電子ガバナ１とメカニカルガバナ２とを備え、電子ガバナ１による電子制御と、メカニカルガバナ２によるメカ制御とを行う、エンジンの燃料供給装置において、
【００１０】
図１または図１０に示すような速度設定手段１８の速度設定で、電子制御特性とメカ制御特性とを設定することにより、図２に示すように、所定の基準負荷Ｌ５よりも低い負荷Ｌ４〜Ｌ１での電子制御の整定回転速度ＮＸが、同一負荷Ｌ４〜Ｌ１でのメカ制御の整定回転速度ｎ４〜ｎ１よりもそれぞれ低くなるようにし、
【００１１】
エンジン運転中、上記基準負荷Ｌ５よりも高い負荷Ｌ６では、メカニカルガバナ２がエンジン回転速度Ｎをメカ制御の整定回転速度ｎ６に整定し、
【００１２】
上記基準負荷Ｌ５よりも低い負荷Ｌ４〜Ｌ１では、電子ガバナ１がエンジン回転速度Ｎを電子制御の整定回転速度ＮＸに整定するようにした、ことを特徴とするエンジンの燃料供給装置。
【００１３】
【発明の作用及び効果】
請求項１の発明は、次の作用効果を奏する。
図１または図１０に示すように、エンジン始動領域７を除く領域での電子ガバナ１による電子制御の最大燃料供給量をメカニカルガバナ２で制限するため、電子ガバナ１にはこの機能が不要となり、そのコストを安くすることができる。また、このような制限を考慮した電子ガバナ１の調整を省略し、或いは簡略化することができ、その調整の手間を軽減することができる。
【００１４】
また、電子制御の最大燃料供給量をメカニカルガバナ２で制限するため、排気ガス特性に実績がある既存のメカニカルガバナ付きエンジンに電子ガバナ１を追加すると、電子制御の最大燃料供給量については、メカニカルガバナ２の実績ある調量特性をそのまま引き継ぐことができる。このため、排気ガス規制をクリアしたメカニカルガバナ付きエンジンに電子ガバナ１を追付けしても、このエンジンは排気ガス特性が変わらない。
【００１５】
また、エンジン運転中、基準負荷Ｌ５よりも低い負荷Ｌ４〜Ｌ１では、電子ガバナ１がエンジン回転速度を、メカニカルガバナ２よりも低く整定するため、部分負荷Ｌ４〜Ｌ２や無負荷Ｌ１でのエンジン騒音を小さくすることができる。
【００１６】
また、基準負荷Ｌ５よりも低い負荷Ｌ４〜Ｌ１での電子制御の整定回転速度ＮＸと、基準負荷Ｌ５での電子制御の整定回転速度ＮＸとを同一の値に設定し、或いは、接近した値に設定することができるため、部分負荷Ｌ４〜Ｌ２及び無負荷Ｌ１でのエンジン騒音を抑制しながら、定格負荷Ｌ５での作業能率を高く維持することができる。
【００１７】
請求項２から請求項６の発明は、次の作用効果を奏する。
請求項２の発明によれば、エンジン発電機等、エンジン回転速度を一定に維持することが必要な用途に有用に用いることができる。
【００１８】
請求項３の発明によれば、図１に示すように、電子制御特性とメカ制御特性との組み合わせによる複数制御特性の変更乃至は設定を単一の操作で容易に行うことができる。
【００１９】
請求項４の発明によれば、図３または図５に示すように、基準負荷の異なる複合制御特性を設定することができ、エンジンの用途に応じて複合制御特性を選択することができる。
【００２０】
請求項５の発明によれば、図１０に示すように、基準負荷の異なる複合制御特性を自由に設定することができるため、エンジンの広範な用途に複合制御特性を適合させることができる。
【００２１】
請求項６の発明によれば、図６に示すように、エンジン回転速度Ｎを定格回転速度ＮＴ以下の速度に制限するため、エンジン騒音を小さくすることができる。尚、請求項２から請求項６の発明によれば、それらが従属する他の請求項の作用効果も奏する。
【００２２】
請求項７の発明によれば、次の作用効果を奏する。
図１または図１０に示すように、電子制御とメカ制御の切り替わり位置が、エンジン始動領域７を除く領域での電子ガバナ１による電子制御の最大燃料供給位置４となるため、請求項１と同様の作用効果を奏する。
また、高負荷に対してメカ制御を行うため、排気ガス特性に実績がある既存のメカニカルガバナ付きエンジンに電子ガバナ１を追加すると、高負荷に対しては、メカニカルガバナ２の実績ある排気ガス特性をそのまま引き継ぐことができる。高負荷での排気ガス特性は、排気ガス規制の重要な規制対象となりうるため、排気ガス規制をクリアしたメカニカルガバナ付きエンジンに電子ガバナ１を追加すると、高負荷での電子ガバナ１の排気ガス特性のテストやデータの収集を省略し、或いは簡略化しても、このエンジンは、排気ガス規制をクリアできる可能性が高い。このため、排気ガス規制をクリアすることができるエンジンを容易に製作することができる。
【００２３】
請求項８から請求項１２の発明によれば、次の作用効果を奏する。
請求項８の発明によれば、請求項２の発明と同様の作用効果を奏し、請求項９の発明によれば、請求項３の発明と同様の作用効果を奏し、請求項１０の発明によれば、請求項４の発明と同様の作用効果を奏し、請求項１１の発明によれば、請求項５の発明と同様の作用効果を奏し、請求項１２の発明によれば、請求項６の発明と同様の作用効果を奏する。
尚、請求項８から請求項１２の発明によれば、それらが従属する他の請求項の作用効果も奏する。
【００２４】
【発明の実施の形態】
本発明の実施の形態を図面に基づいて説明する。図１から図９は本発明の第１実施形態に係るディーゼルエンジンの燃料供給装置を説明する図である。
この燃料供給装置の概要は、次の通りである。
図１に示すように、この燃料供給装置は、電子ガバナ１とメカニカルガバナ２とを備え、電子ガバナ１による電子制御と、メカニカルガバナ２によるメカ制御とを行う。そして、燃料調量部３の調量領域のうち、エンジン始動領域７を除く領域での電子ガバナ１による電子制御の最大燃料供給量(ディーゼルエンジンの場合、最大燃料噴射量といいかえてもよい)をメカニカルガバナ２で制限する。燃料調量部３は、燃料噴射ポンプの燃料調量ラックである。燃料調量部３は、電子入力部１１とメカ入力部１２とを備えている。電子入力部１１は、燃料調量ラックの燃料増量側の端面であり、メカ入力部１２は、ラックピンである。燃料調量部３は、付勢バネ１３の付勢バネ力１３ａで燃料増量方向に付勢されている。
【００２５】
メカニカルガバナ２の構成は、次の通りである。
図１に示すように、メカニカルガバナ２は、ガバナレバー２１と、ガバナスプリング１９と、ガバナウェイト２０と、燃料制限具２５とを備えている。ガバナレバー２１は、第１レバー２１ａと第２レバー２１ｂとを備えている。第１レバー２１ａは、ガバナスプリング１９と連動レバー２３と連動ロッド２２とを介して、速度設定手段１８に連動連結されている。この速度設定手段１８の速度設定で、ガバナスプリング１９のガバナスプリング力１９ａを調節する。第２レバー２１ｂは、出力部１０と、トルクアップ装置２６とを備えている。出力部１０は、付勢バネ力１３ａで付勢された燃料調量具３のメカ入力部１２を受け止める。
【００２６】
トルクアップ装置２６は、トルクケース２６ａと、トルクピン２６ｂと、トルクバネ２６ｃとを備えている。トルクケース２６ａは、第２レバー２１ｂに進退自在に取り付けられている。トルクピン２６ｂは、トルクバネ２６ｃのトルクバネ力２６ｄで、トルクケース２６ａから押し出される方向に付勢され、その先端部は、第１レバー２１ａと対向する。ガバナウェイト２０は、第２レバー２１ｂと対向する。ガバナウェイト２０はエンジン回転速度Ｎに応じてガバナ力２０ａを生じさせる。燃料制限具２５は、ギヤケース壁に進退自在に取り付けられ、その先端は、第２レバー２１ｂと対向する。尚、燃料制限具２５の進退調節により、定格負荷出力を調節することができ、トルクケース２６ａの進退調節により、定格過超負荷時の燃料増量の上限を調節することができる。
【００２７】
メカニカルガバナ２の作動は、次の通りである。
エンジン運転中、第１レバー２１ａが燃料制限具２５の先端に受け止められるまでは、ガバナスプリング力１９ａとガバナ力２０ａと付勢バネ力１３ａとの不釣り合い力により、第１レバー２１ａと第２レバー２１ｂとが一体に揺動する。負荷の増加により、エンジン回転速度が低下し、第１レバー２１ａが燃料制限具２５の先端に受け止められると、トルクスプリング力１９ａとガバナ力２０ａと付勢バネ力１３ａとの不釣り合い力により、第２レバー２１ｂのみが揺動する。エンジン始動時は、エンジン回転速度Ｎが図２の始動増量終了の回転速度ｎ８に至るまでは、ガバナ力２０ａが小さいため、付勢バネ力１３ａで燃料調量部３を始動増量領域７に保持し、始動増量を可能にする。この場合、第２レバー２１は、燃料調量部３に押されて大きく傾き、始動増量を邪魔しない。尚、図２中のｎ７は始動が確定するアイドル回転速度である。
【００２８】
電子ガバナ１の構成は、次の通りである。
図１に示すように、電子ガバナ１は、コントローラ１６と、アクチュエータ１７と、設定速度検出手段１８ｃと、回転速度検出手段１５と、基準負荷変更手段Ｍとを備えている。アクチュエータ１７は、リニアリレノイドであり、出力ロッド３４とスプリング３３と電磁コイル３５とを備えている。出力ロッド３４の先端の出力部９は、燃料調量部３の電子入力部１１を受け止める。スプリング３３は、出力ロッド３４を押し出し方向に付勢する。電磁コイル３５は、出力ロッド３４を引き込み方向に吸引する。
【００２９】
設定速度検出手段１８ｃは、速度設定手段１８の速度設定位置を検出するポテンショメータで、この速度設定位置に対応する速度設定電圧を速度設定信号としてコントローラ１６に発信する。速度設定手段１８は、電子ガバナ１とメカニカルガバナ２との双方の速度設定を兼ねる単一のものであり、この単一の速度設定手段１８の速度設定で、電子制御特性とメカ制御特性とを一連に設定することができる。また、速度設定検出手段１８ｃで、電子ガバナ１の設定速度と、メカニカルガバナ２の設定速度の双方を検出することができる。速度検出手段１５は、エンジン回転速度Ｎを検出し、速度検出信号をコントローラ１６に発信する。また、基準負荷変更手段Ｍは、切り替えレバーを備え、この切り替えレバーでモードＭ１とモードＭ２とを選択することにより、基準負荷を変更する。基準負荷については後述する。この電子ガバナ１は燃料調量部３の燃料調量位置を直接に検出する調量位置検出手段３０を備えている。この調量位置検出手段３０は、燃料調量部３の調量位置検出信号をコントローラ１６に発信する。
【００３０】
コントローラ１６は、次の処理を行う。
設定速度検出手段１８ｃからの速度設定信号と基準負荷変更手段Ｍのモード選択に基づいて電子制御特性を設定する。速度検出信号を受け、電子制御特性に基づいて定めた電子制御の整定回転速度ＮＸとエンジン回転速度Ｎとの回転偏差を演算する。調量位置検出信号を受け、上記回転偏差の演算結果と調量位置とに基づいて、ＰＷＭ波のデューティ比を設定する。アクチュエータ１７の電磁コイル３５に通電を行う通電回路のスイッチング素子にＰＷＭ波を発信し、アクチュエータ１７の出力を調節する。
【００３１】
電子制御特性とメカ制御特性の設定方法と内容は、次の通りである。
図１に示す速度設定手段１８の速度設定を高速とし、基準負荷変更手段ＭをモードＭ１に設定すると、図２に示す制御特性線図が得られる。この制御特性線図は、負荷に対するメカ制御と電子制御の各整定回転速度等を示すものである。図２中の実線はメカ制御特性線５０を示しており、メカ制御特性線図５０のうち、垂直に近い傾線はメカ調速線５１、水平に近い傾斜線はトルクアップ線５２、水平線は全負荷線５３を示す。また、一点鎖線は電子調速線６０を示す。定格負荷Ｌ５から無負荷Ｌ１でのメカ制御特性は、負荷が低下するにつれて、各整定回転速度ｎ５〜ｎ１が次第に高くなるドループ制御特性となる。定格過超負荷領域では、負荷が増加するにつれて、その整定回転速度ｎ６が定格負荷Ｌ５での整定回転速度ｎ５よりも低くなるトルクアップ制御特性となる。電子制御特性は、定格過超負荷Ｌ６から無負荷Ｌ１の各整定回転速度ＮＸが同一の値をとるアイソクロナス制御特性となる。尚、電子調速線６０は、メカ調速線５１と同様、ドループ制御特性となるように設定してもよい。
【００３２】
電子制御特性とメカ制御特性との関係は、次の通りである。
メカ制御特性線５０と電子調速線６０とが交叉する点の負荷を基準負荷と定義する。基準負荷変更手段ＭをモードＭ１に設定した場合、図２に示すように、定格負荷Ｌ５が基準負荷となる。基準負荷となる定格負荷Ｌ５での電子制御の整定回転速度ＮＸは、同一負荷Ｌ５でのメカ制御の整定回転速度ｎ５と一致する。定格負荷Ｌ５よりも低い部分負荷Ｌ４〜無負荷Ｌ１での電子制御の整定回転速度ＮＸは、同一負荷Ｌ４〜Ｌ１でのメカ制御の整定回転速度ｎ４〜ｎ１よりもそれぞれ低くなる。定格過超負荷Ｌ６でのトルクアップの整定回転速度ｎ６は、同一負荷Ｌ６での電子制御の整定回転速度ＮＸよりも低くなる。エンジンに所定負荷がかかった時、その負荷に対する整定回転速度が遅い方の制御が優先し、エンジン回転速度はその遅い方の整定回転速度に整定されることになる。
【００３３】
エンジン回転速度Ｎの整定内容は、次の通りである。
エンジン運転中、上記基準負荷となる定格負荷Ｌ５では、電子ガバナ１とメカニカルガバナ２が、エンジン回転速度Ｎを電子制御とメカ制御の各整定回転速度ＮＸ・ｎ５に整定する。この各整定回転速度ＮＸ・ｎ５は、同一の値である。定格負荷Ｌ５よりも低い部分負荷Ｌ４〜無負荷Ｌ１では、電子ガバナ１がエンジン回転速度Ｎを電子制御の整定メカ回転速度ＮＸに整定する。定格過超負荷Ｌ６では、メカニカルガバナ２がエンジン回転速度Ｎを最大トルク回転速度ＮＭに近いトルクアップ回転速度ｎ６まで下降させる。
【００３４】
上記エンジン回転速度Ｎの整定方法は、次の通りである。
エンジン運転中、上記基準負荷となる定格負荷Ｌ５では、電子調速線６０とメカ調速線５１とに基づいて、電子制御による燃料調量部３の整定位置とメカ制御による整定位置とが一致し、これがエンジン始動領域７を除く領域での電子ガバナ１による電子制御の最大燃料供給位置４(ディーゼルエンジンの場合、最大燃料噴射位置といいかえてもよい)となる。この場合、電子ガバナ１の出力部９が燃料調量部３の電子入力部１１を、メカニカルガバナ２の出力部１０が燃料調量部３のメカ入力部１２をそれぞれ受け止め、電子ガバナ１とメカニカルガバナ２の両方が、燃料調量部３を上記電子制御の最大燃料供給位置４に整定し、エンジン回転速度Ｎを電子制御とメカ制御の整定回転速度ＮＸ・ｎ５に整定する。
【００３５】
基準負荷となる定格負荷Ｌ５よりも低い部分負荷Ｌ４〜無負荷Ｌ１では、電子調速線６０に基づいて調速領域５の全ての領域５ａで電子制御のみが行われ、電子ガバナ１の出力部９が燃料調量部３の電子入力部１１を受け止め、メカニカルガバナ２の出力部１０が燃料調量部３のメカ入力部１２から燃料増量側に離れ、電子ガバナ１が燃料調量部３を電子制御の最大燃料供給位置４よりも燃料減量側の領域５ａで整定し、エンジン回転速度Ｎを電子制御の整定回転速度ＮＸに整定する。尚、調速領域５とは、調量領域のうち、電子調速線６０またはメカ調速線５１の少なくとも一方に基づいて調速制御が行われる領域をいう。
【００３６】
基準負荷Ｌ５よりも高い定格過超負荷Ｌ６では、トルクアップ線５２に基づいて、トルクアップ領域６でメカニカルガバナ２の出力部１０が燃料調量部３のメカ入力部１２を受け止め、電子ガバナ１の出力部９が燃料調量部３の電子入力部１１から燃料増量側に離れ、メカニカルガバナ２が燃料調量部３を電子制御の最大燃料供給位置４よりも燃料増量側のトルクアップ領域６で整定し、エンジン回転速度Ｎをトルクアップ回転速度ｎ６まで下降させる。
【００３７】
負荷変動時の過渡特性は、次の通りである。
基準負荷となる定格負荷Ｌ５から部分負荷Ｌ４〜無負荷Ｌ１に負荷が減少すると、メカニカルガバナ２の出力部１０が燃料調量部３のメカ入力部１２から燃料増量側に離れ、電子制御がメカ制御に優先して制御を行う。逆に定格負荷Ｌ５から定格過超負荷Ｌ６に負荷が増加すると、アクチュエータ１７の出力部９が燃料調量部３の電子入力部１１から燃料増量側に離れ、メカ制御が電子制御に優先してトルクアップを行う。電子制御時には、メカニカルガバナ２の作動が外乱要素として入力されず、また、トルクアップ時には、電子ガバナ１の作動が外乱要素として入力されないため、電子制御とトルクアップの精度が高くなる。また、電子ガバナ１のアクチュエータ１７に小型小出力のものを用いることができる。
【００３８】
ただし、電子制御とメカ制御の整定速度の相違などにより、電子制御中、電子ガバナ１の出力部９が燃料増量側に行き過ぎ、或いは、メカニカルガバナ２の出力部１０が燃料増量側に速やかに作動しない場合には、一時的に燃料調量部３のメカ入力部１２がメカニカルガバナ２の出力部１０で受け止められ、電子ガバナ１の出力部９が燃料調量部３の電子入力部１１から離れることがある。また、逆に、トルクアップ中、メカニカルガバナ２の出力部１０が燃料増量側に行き過ぎ、或いは、電子ガバナ１の出力部９が燃料増量側に速やかに作動しない場合には、燃料調量部３の電子入力部１１が電子ガバナ１の出力部９で受け止められ、メカニカルガバナ２の出力部１０が一時的に燃料調量部３のメカ入力部１２から離れることがある。
【００３９】
基準負荷の変更方法と変更内容は、次の通りである。
図１に示す速度設定手段１８を高速位置に設定したまま、基準負荷変更手段ＭをモードＭ２に切り替えると、図３に示すように、一点鎖線で示す電子調速線６０のみが高速側にずれ、基準負荷が定格負荷Ｌ５から部分負荷Ｌ３の高さに変更される。この場合、新たな基準負荷となる部分負荷Ｌ３での電子制御の整定回転速度ＮＸは、同一負荷Ｌ３でのメカ制御の整定回転速度ｎ３と一致する。部分負荷Ｌ３よりも低い部分負荷Ｌ２〜無負荷Ｌ１での電子制御の整定回転速度ＮＸは、同一負荷Ｌ２〜Ｌ１でのメカ制御の整定回転速度ｎ２〜ｎ１よりもそれぞれ低くなる。部分負荷Ｌ３よりも高い部分負荷Ｌ４〜定格過超負荷Ｌ６でのメカ制御の整定回転速度ｎ４〜ｎ６は、同一負荷Ｌ４〜Ｌ６での電子制御の整定回転速度ＮＸよりもそれぞれ低くなる。このようにして、電子制御の最大燃料供給位置４を変更することができる。
【００４０】
エンジン回転速度Ｎの整定内容は、次の通りである。
エンジン運転中、上記基準負荷となる部分負荷Ｌ３では、電子調速線６０とメカ調速線５１とに基づいて、電子ガバナ１とメカニカルガバナ２の両方が、燃料調量部３を電子制御の最大燃料供給位置４に整定し、エンジン回転速度Ｎを電子制御とメカ制御の整定回転速度ＮＸ・ｎ３に整定する。部分負荷Ｌ３よりも低い部分負荷Ｌ２〜無負荷Ｌ１では、電子調速線６０に基づいて、電子ガバナ１が調速領域５のうち、電子制御の最大燃料供給位置４よりも燃料減量側の領域５ａで燃料調量部３を整定し、エンジン回転速度Ｎを電子制御の整定回転速度ＮＸに整定する。部分負荷Ｌ３よりも高い部分負荷Ｌ４〜定格負荷Ｌ５ではメカ調速線５１に基づいて、メカニカルガバナ２が電子制御の最大燃料供給位置４よりも燃料増量側の領域５ｂで燃料調量部３を整定し、エンジン回転速度Ｎをメカ制御の整定回転速度ｎ４〜ｎ５に整定する。この場合、電子制御での燃料調量部３の最大燃料供給位置４が燃料調量部３の調速領域５の途中にくるため、この最大燃料供給位置４で電子制御とメカ制御とが自動的に切り替わる。定格過超負荷Ｌ６ではトルクアップ線５２に基づいてメカニカルガバナ２がトルクアップを行う。尚、この場合、軽負荷Ｌ２〜無負荷Ｌ１では、電子制御による整定を行うため、前記付勢バネ力１３ａを小さくしても、メカ制御に比べ、ハンチングが起こりにくい。このため、アクチュエータ１７に小型小出力のものを用いることができる。
【００４１】
負荷変動時の過渡特性は、次の通りである。
基準負荷となる部分負荷Ｌ３から部分負荷Ｌ２〜無負荷Ｌ１に負荷が減少すると、電子制御がメカ制御に優先して制御を行う。逆に基準負荷となる部分負荷Ｌ３から部分負荷Ｌ４〜定格負荷Ｌ５に負荷が増加すると、メカ制御が電子制御に優先して制御を行う。基準負荷となる部分負荷Ｌ３よりも低い負荷Ｌ１〜Ｌ２から定格過超負荷Ｌ６に負荷が増加すると、最初、電子制御がメカ制御に優先して制御を行うが、途中からメカ制御が電子制御に優先して制御を行う。尚、基準負荷が定格負荷Ｌ５の場合と同様の理由で、電子制御中、燃料調量部３のメカ入力部１２がメカニカルガバナ２の出力部１０で受け止められ、メカ制御中、燃料調量部３の電子入力部１１が電子ガバナ１の出力部９で受け止められることがある。
【００４２】
速度設定の変更方法と変更内容は、次の通りである。
図１に示す基準負荷変更手段ＭをモードＭ１に設定したまま、速度設定手段１８の速度設定を高速から低速に変更すると、図４に示すように、一点鎖線で示す電子調速線６０と実線で示すメカ調速線５１がいずれも低速側に平行移動する。また、基準負荷変更手段ＭをモードＭ２に設定したまま、速度設定手段１８の速度設定を高速から低速に変更すると、図５に示すように、一点鎖線で示す電子調速線６０と実線で示すメカ調速線５１がいずれも低速側に平行移動する。尚、速度設定手段１８の速度設定を高速から低速側に大きくずらすと、トルクアップ特性は消失する。
【００４３】
エンジン回転速度Ｎの制限方法と制限内容は、次の通りである。
図１に示す基準負荷変更手段ＭをモードＭ２にセットし、速度設定手段１８の速度設定を高速にした場合、図３に示すように、基準負荷となる部分負荷Ｌ３での電子制御の整定回転速度ＮＸがエンジンの定格回転速度ＮＴを越える。この場合、図１に示す速度制限スイッチ２９を入れておくと、図６に示すように、コントローラ１６が基準負荷を部分負荷Ｌ３から定格負荷Ｌ５に変更する。この場合、エンジン運転中、新たな基準負荷となる定格負荷Ｌ５以下の定格負荷Ｌ５〜無負荷Ｌ１では、電子ガバナ１がエンジン回転速度Ｎを定格回転速度ＮＴと同じ電子制御の整定回転速度ＮＸ´に整定し、新たな基準負荷となる定格負荷Ｌ５を越える定格過超負荷Ｌ６では、メカニカルガバナ２がエンジン回転速度Ｎを定格回転速度ＮＴよりも低いトルクアップの回転速度ｎ６まで低下させる。
【００４４】
メカ単独制御の設定方法と設定内容は、次の通りである。
図１に示す電子作動停止スイッチ３１を入れておくと、アクチュエータ１７の出力部９が燃料調量部３の電子入力部１１の作動範囲から燃料増量側に外れた作動停止位置１７ａで静止する。この場合、電子制御とメカ制御との複合制御が、図７に示すメカ単独制御に切り替わる。
【００４５】
エンジンを停止するための構成は、次の通りである。
この燃料供給装置は、図１に示すように、手動のエンジン停止手段２７を備え、このエンジン停止手段２７は、停止操作レバー２７ａと停止出力部２７ｂとを備えている。停止出力部２７ｂは筒状で、エンジン機壁２８のガイド孔２８ａに進退自在に挿通され、この先端は燃料調量部３の電子入力部１１に臨んでいる。停止操作レバー２７ａで停止出力部２７ｂを燃料減量側に押すと、その先端が電子入力部１１に接当し、付勢バネ力１３ａに抗して、燃料調量部３を燃料供給停止位置８まで押す。また、アクチュエータ１７で、燃料調量部３を燃料供給停止位置８まで押すこともできる。このため、エンジン停止装置の専用回路や専用アクチュエータが不要になる。尚、アクチュエータ１７の出力部９はスプリング３３で付勢されているため、電子ガバナ１の故障により、アクチュエータ１７への通電が解除されると、スプリング３３の付勢力により、出力部９で燃料調量部３を燃料供給停止位置８まで押し、ここに留め置く。この場合、エンジンを再始動できないため、電子ガバナ１の故障を確認できる。
【００４６】
電子ガバナ１は、次の補正機能を備えている。
電子ガバナ１は、冷始動でない場合には、冷始動の場合よりも、燃料供給量を減量補正する。このため、図１に示すように、電子ガバナ１は温度検出手段３７を備える。電子ガバナ１は、検出したエンジン温度が所定値を越える場合には、これが所定値未満である場合に比べ、エンジン始動領域７での燃料供給量を少なくする。すなわち、燃料調量部３を始動増量制限位置７ａに保持する。エンジン温度は、エンジン機壁温度、エンジン冷却水温度、エンジンオイル温度を検出することによって検出できる。また、冷始動か否かの判断は、エンジン周辺の外気温度を検出することによっても行うことができる。この場合、黒煙の発生や燃料の無駄な消費を抑制することができる。
【００４７】
また、電子ガバナ１は、吸気のブースト圧検出手段３８を備え、過給されている吸気の圧力が十分に高まるまでは、燃料供給量を制限補正するブーコン機能を備える。また、電子ガバナ１は、大気圧検出手段３９を備え、大気圧が低い場合には、燃料供給量を減量補正する高地補正機能を備える。また、電子ガバナ１は、操作速度検出手段４０を備え、速度設定手段１８の操作速度が速すぎる場合には、出力部９の作動速度を抑制して、燃料調量部３のオーバーシュートを抑制する機能を備える。
図８は、第１実施形態の第１変形例を示しており、この第１変形例では、図１に示す速度設定手段１８の速度設定を高速とし、基準負荷変更手段ＭをモードＭ１に設定すると、図８中に鎖線で示す電子調速線６０が最大負荷Ｌ７の位置でトルクアップ線５２の上限と交叉する。図９は、第１実施例の第２変形例を示しており、この第２変形例では、図１に示す速度設定手段１８の速度設定を低速とし、基準負荷変更手段ＭをモードＭ１に設定すると、図９に示すように、無負荷Ｌ１〜定格過超負荷Ｌ６での電子制御の整定回転速度ＮＸが最大トルク回転速度ＮＭよりも低い場合には、コントローラ１６がアイソクロナス制御特性をドループ制御特性に変更し、負荷が増加するにつれて、電子制御の整定回転速度ＮＸが最大トルク回転速度ＮＭに近づくようにする。
【００４８】
第２実施形態について説明する。
図１０〜図１２は、第２実施形態に係るディーゼルエンジンの燃料供給装置を説明する図である。この第２実施形態は、第１実施形態と次の点で相違する。
図１０に示すように、速度設定手段１８を、電子ガバナ１の速度設定手段１８ａとメカニカルガバナ２の速度設定手段１８ｂとで構成し、これらの各速度設定手段１８ａ・１８ｂの速度設定で、電子制御特性とメカ制御特性とを個別に設定することにより、基準負荷の高さを自由に設定できるようにしている。
【００４９】
メカニカルガバナ２の速度設定手段１８ｂにはペダルを用い、これを連動ロッド２２に連結している。この連動ロッド２２の近くに係止レバー２４を設け、速度設定手段１８ｂを任意の設定位置に動かした後、係止レバー２４で連動ロッド２２を係止すると、速度設定手段１８ｂはその設定位置よりも低速側には戻らない。電子ガバナ１の速度設定手段１８ａは、手動レバーであり、この速度設定位置は設定速度検出手段１８ｃで検出する。基準負荷変更手段Ｍは不要となるため、備えていない。他の構成は、第１実施形態と同じである。尚、図１０〜図１２中、第１実施形態と同一の要素には、同一の符号を付しておく。
【００５０】
電子制御特性とメカ制御特性の設定方法と設定内容は次の通りである。
各速度設定手段１８ａ・１８ｂの速度設定をいずれも高速にすると、図２と同じ複合制御特性が得られ、定格負荷Ｌ５を基準負荷に設定した高速運転を行うことができる。この状態から、電子ガバナ１の速度設定手段１８ａだけを僅かに高速側にずらすと、図３と同じ複合制御特性が得られ、部分負荷Ｌ３を基準負荷に設定した高速運転を行うことができる。
【００５１】
各速度設定手段１８ａ・１８ｂの速度設定をいずれも低速にすると、図４と同じ複合制御特性が得られ、定格負荷Ｌ５を基準負荷に設定した低速運転を行うことができる。この状態から、電子ガバナ１の速度設定手段１８だけを僅かに高速側にずらすと、図５と同じ複合制御特性が得られ、部分負荷Ｌ３を基準負荷に設定した低速運転が行える。各速度設定手段１８ａ・１８ｂの速度設定を各種組み合わせると、速度設定と基準負荷とを異にする各種の複合制御特性を得ることができる。
【００５２】
電子ガバナ１の速度設定手段１８ａの速度設定を高速にし、メカニカルガバナ２の速度設定手段１８ｂの速度設定を低速にすると、図１１に示すように、無負荷Ｌ１〜過負荷Ｌ６でのメカ制御の整定回転速度ｎ１〜ｎ６が同一負荷Ｌ１〜Ｌ６での電子制御の整定回転速度ＮＸよりもそれぞれ低くなるため、電子制御が行われず、電子制御とメカ制御との複合制御を、メカ単独制御に切り替えることができる。
【００５３】
電子ガバナ１の速度設定手段１８ａの速度設定を低速にし、メカニカルガバナ２の速度設定手段１８ｂの速度設定を高速にし、図１２に示すように、無負荷Ｌ１〜定格過超負荷Ｌ６での電子制御の整定回転速度ＮＸが最大トルク回転速度ＮＭよりも低くなる場合には、コントローラ１６がアイソクロナス制御特性をドループ制御特性に変更し、負荷が増加するにつれて電子制御の整定回転速度ＮＸが、最大トルク回転速度ＮＭに近づくようにする。
【図面の簡単な説明】
【図１】第１実施形態の電子ガバナとメカニカルガバナの模式図である。
【図２】第１実施形態の高速設定時のモードＭ１での制御特性線図である。
【図３】第１実施形態の高速設定時のモードＭ２での制御特性線図である。
【図４】第１実施形態の低速設定時のモードＭ１での制御特性線図である。
【図５】第１実施形態の低速設定時のモードＭ２での制御特性線図である。
【図６】第１実施形態の速度制限時の制御特性線図である。
【図７】第１実施形態のメカ単独制御時の制御特性線図である。
【図８】第１実施形態の第１変更例の高速設定時のモードＭ１での制御特性線図である。
【図９】第１実施形態の第２変更例の低速設定時のモードＭ１での制御特性線図である。
【図１０】第２実施形態の電子ガバナとメカニカルガバナの模式図である。
【図１１】第２実施形態のメカ単独制御時の制御特性線図である。
【図１２】第２実施形態のドループ制御時の制御特性線図である。
【符号の説明】
１…電子ガバナ、２…メカニカルガバナ、３…燃料調量部、Ｌ６〜Ｌ１…負荷、ＮＸ…電子制御の整定回転速度、ｎ６〜ｎ１…メカ制御の整定回転速度、Ｎ…エンジン回転速度、１８…速度設定手段、１８ａ…電子ガバナの速度設定手段、１８ｂ…メカニカルガバナガバナの速度設定手段、Ｍ…基準負荷変更手段、ＮＴ…定格回転速度。[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a fuel supply apparatus for an engine, and more particularly, to an apparatus having both an electronic governor and a mechanical governor.
[0002]
[Prior art]
Conventionally equipped with an electronic governor and a mechanical governor, which performs electronic control by the electronic governor and mechanical control by the mechanical governor, and switches between the electronic independent control mode and the mechanical independent control mode as an engine fuel supply device It has been known.
[0003]
In the case of this prior art, the speed regulation and the maximum fuel supply amount are limited only by the electronic governor in the electronic single control mode and only by the mechanical governor in the mechanical single control mode, respectively.
[0004]
[Problems to be solved by the invention]
The above prior art has the following problems.
In the electronic single control mode, since it is necessary to limit the maximum fuel supply amount of electronic control with the electronic governor, it is necessary to use an electronic governor having such a limiting function, and the cost of the electronic governor increases. In addition, it is necessary to adjust the electronic governor in consideration of such restrictions, and this adjustment takes time.
[0005]
The subject of this invention is providing the fuel metering apparatus of an engine which can solve the said problem.
[0006]
[Means for Solving the Problems]
The configuration of the invention of claim 1 is as follows.
As shown in FIG. 1 or FIG. 10, the electronic governor 1 and the mechanical governor 2 are provided, and the maximum of electronic control by the electronic governor 1 in the region excluding the engine start region 7 in the metering region of the fuel metering unit 3. Limit the fuel supply amount with the mechanical governor 2,
[0007]
As shown in FIG. 1 or FIG. 10, by setting the electronic control characteristics by the electronic governor 1 and the mechanical control characteristics by the mechanical governor 2 by setting the speed of the speed setting means 18, as shown in FIG. When the reference load L5, the fuel metering means 3 is positioned at the maximum fuel supply position 4 of the electronic control,
[0008]
The electronically controlled settling rotational speed NX at loads L4 to L1 lower than the predetermined reference load L5 is made lower than the mechanically controlled settling rotational speeds n4 to n1 at the same loads L4 to L1, respectively. The engine fuel supply apparatus, wherein the electronic governor 1 sets the engine rotational speed N to the electronically controlled set rotational speed NX at loads L4 to L1 lower than the reference load L5.
[0009]
The configuration of the invention of claim 7 is as follows.
As shown in FIG. 1 or FIG. 10, an engine fuel supply apparatus that includes an electronic governor 1 and a mechanical governor 2 and performs electronic control by the electronic governor 1 and mechanical control by the mechanical governor 2.
[0010]
By setting the electronic control characteristic and the mechanical control characteristic by the speed setting of the speed setting means 18 as shown in FIG. 1 or FIG. 10, as shown in FIG. 2, loads L4 to L4 lower than a predetermined reference load L5 The electronic control settling speed NX at L1 is lower than the mechanical control settling speed n4 to n1 at the same load L4 to L1, respectively.
[0011]
During engine operation, at a load L6 higher than the reference load L5, the mechanical governor 2 sets the engine rotational speed N to a mechanically controlled set rotational speed n6,
[0012]
The engine fuel supply apparatus, wherein the electronic governor 1 sets the engine rotational speed N to an electronically controlled set rotational speed NX at loads L4 to L1 lower than the reference load L5.
[0013]
[Action and effect of the invention]
The invention of claim 1 has the following effects.
As shown in FIG. 1 or FIG. 10, since the maximum fuel supply amount of electronic control by the electronic governor 1 in the region excluding the engine start region 7 is limited by the mechanical governor 2, the electronic governor 1 does not need this function. The cost can be reduced. Further, the adjustment of the electronic governor 1 in consideration of such restrictions can be omitted or simplified, and the labor of the adjustment can be reduced.
[0014]
In addition, since the maximum fuel supply amount for electronic control is limited by the mechanical governor 2, if the electronic governor 1 is added to an engine with an existing mechanical governor that has a proven track record in exhaust gas characteristics, the maximum fuel supply amount for electronic control The proven metering characteristic of the governor 2 can be taken over as it is. For this reason, even if the electronic governor 1 is added to an engine with a mechanical governor that has cleared exhaust gas regulations, the exhaust gas characteristics of this engine do not change.
[0015]
Further, during engine operation, at loads L4 to L1 lower than the reference load L5, the electronic governor 1 sets the engine rotation speed lower than that of the mechanical governor 2, so that the engine noise at the partial loads L4 to L2 and no load L1. Can be reduced.
[0016]
Also, the electronically controlled settling rotational speed NX at the loads L4 to L1 lower than the reference load L5 and the electronically controlled settling rotational speed NX at the reference load L5 are set to the same value or close to each other. Since it can be set, the working efficiency at the rated load L5 can be maintained high while suppressing engine noise at the partial loads L4 to L2 and the no load L1.
[0017]
The inventions according to claims 2 to 6 have the following effects.
According to invention of Claim 2, it can use usefully for the use which needs to maintain an engine rotational speed constant, such as an engine generator.
[0018]
According to the invention of claim 3, as shown in FIG. 1, the change or setting of the plurality of control characteristics by the combination of the electronic control characteristics and the mechanical control characteristics can be easily performed by a single operation.
[0019]
According to the invention of claim 4, as shown in FIG. 3 or FIG. 5, it is possible to set composite control characteristics with different reference loads, and it is possible to select composite control characteristics according to the application of the engine.
[0020]
According to the invention of claim 5, as shown in FIG. 10, the composite control characteristics with different reference loads can be freely set, so that the composite control characteristics can be adapted to a wide range of uses of the engine.
[0021]
According to the sixth aspect of the present invention, as shown in FIG. 6, the engine speed N is limited to a speed equal to or lower than the rated speed NT, so that the engine noise can be reduced. In addition, according to invention of Claim 2-6, there exists an effect of the other claim in which they depend.
[0022]
According to invention of Claim 7, there exists the following effect.
As shown in FIG. 1 or 10, the switching position between the electronic control and the mechanical control is the maximum fuel supply position 4 of the electronic control by the electronic governor 1 in the region excluding the engine start region 7. Has the effect of.
In addition, when mechanical governor 2 is added to an engine with an existing mechanical governor that has a proven track record in exhaust gas characteristics to perform mechanical control for high loads, the exhaust gas characteristics of mechanical governor 2 are proven for high loads. Can be taken over as is. Exhaust gas characteristics at high loads can be an important target for exhaust gas regulations. Therefore, if the electronic governor 1 is added to an engine with a mechanical governor that has cleared the exhaust gas regulations, the exhaust gas characteristics of the electronic governor 1 at high loads. Even if this test or data collection is omitted or simplified, the engine is likely to be able to meet exhaust gas regulations. For this reason, it is possible to easily manufacture an engine that can satisfy the exhaust gas regulations.
[0023]
According to the eighth to twelfth aspects of the present invention, the following effects can be obtained.
According to the invention of claim 8, the same effect as that of the invention of claim 2 is achieved, and according to the invention of claim 9, the effect of the same effect as that of the invention of claim 3 is achieved. According to the invention of claim 4, the same effect as that of the invention of claim 4 is achieved. According to the invention of claim 11, the effect of the same effect as that of the invention of claim 5 is achieved. The same effects as those of the present invention can be obtained.
In addition, according to invention of Claims 8-12, there exists an effect of the other claim in which they depend.
[0024]
DETAILED DESCRIPTION OF THE INVENTION
Embodiments of the present invention will be described with reference to the drawings. 1 to 9 are diagrams for explaining a fuel supply device for a diesel engine according to a first embodiment of the present invention.
The outline of this fuel supply apparatus is as follows.
As shown in FIG. 1, the fuel supply apparatus includes an electronic governor 1 and a mechanical governor 2, and performs electronic control by the electronic governor 1 and mechanical control by the mechanical governor 2. In the metering region of the fuel metering unit 3, the maximum fuel supply amount of electronic control by the electronic governor 1 in the region excluding the engine start region 7 (in the case of a diesel engine, it may be referred to as the maximum fuel injection amount). Is restricted by the mechanical governor 2. The fuel metering unit 3 is a fuel metering rack of the fuel injection pump. The fuel metering unit 3 includes an electronic input unit 11 and a mechanical input unit 12. The electronic input unit 11 is an end surface on the fuel increase side of the fuel metering rack, and the mechanical input unit 12 is a rack pin. The fuel metering unit 3 is biased in the fuel increasing direction by the biasing spring force 13 a of the biasing spring 13.
[0025]
The configuration of the mechanical governor 2 is as follows.
As shown in FIG. 1, the mechanical governor 2 includes a governor lever 21, a governor spring 19, a governor weight 20, and a fuel limiter 25. The governor lever 21 includes a first lever 21a and a second lever 21b. The first lever 21 a is linked to the speed setting means 18 via the governor spring 19, the linkage lever 23, and the linkage rod 22. The governor spring force 19 a of the governor spring 19 is adjusted by the speed setting of the speed setting means 18. The second lever 21 b includes the output unit 10 and a torque increase device 26. The output unit 10 receives the mechanical input unit 12 of the fuel metering tool 3 biased by the biasing spring force 13a.
[0026]
The torque increase device 26 includes a torque case 26a, a torque pin 26b, and a torque spring 26c. The torque case 26a is attached to the second lever 21b so as to freely advance and retract. The torque pin 26b is urged in the direction of being pushed out of the torque case 26a by the torque spring force 26d of the torque spring 26c, and the tip thereof faces the first lever 21a. The governor weight 20 faces the second lever 21b. The governor weight 20 generates a governor force 20a according to the engine speed N. The fuel limiter 25 is attached to the gear case wall so as to be able to advance and retreat, and the tip thereof faces the second lever 21b. The rated load output can be adjusted by adjusting the advance / retreat of the fuel limiter 25, and the upper limit of the fuel increase at the time of the rated overload can be adjusted by adjusting the advance / retreat of the torque case 26a.
[0027]
The operation of the mechanical governor 2 is as follows.
During engine operation, until the first lever 21a is received at the tip of the fuel limiter 25, the first lever 21a and the second lever are caused by the unbalanced forces of the governor spring force 19a, the governor force 20a, and the biasing spring force 13a. 21b swings together. When the engine speed decreases due to an increase in the load and the first lever 21a is received at the tip of the fuel limiter 25, the unbalanced force among the torque spring force 19a, the governor force 20a, and the biasing spring force 13a causes Only the two lever 21b swings. When the engine starts, the governor force 20a is small until the engine rotation speed N reaches the rotation speed n8 at the end of the start increase in FIG. 2, so the fuel metering unit 3 is held in the start increase area 7 by the biasing spring force 13a. And increase the starting amount. In this case, the second lever 21 is greatly inclined by being pushed by the fuel metering unit 3 and does not interfere with the starting increase. Note that n7 in FIG. 2 is an idle rotation speed at which start is determined.
[0028]
The configuration of the electronic governor 1 is as follows.
As shown in FIG. 1, the electronic governor 1 includes a controller 16, an actuator 17, a set speed detection unit 18 c, a rotation speed detection unit 15, and a reference load change unit M. The actuator 17 is a linear rerenoid, and includes an output rod 34, a spring 33, and an electromagnetic coil 35. The output unit 9 at the tip of the output rod 34 receives the electronic input unit 11 of the fuel metering unit 3. The spring 33 biases the output rod 34 in the pushing direction. The electromagnetic coil 35 attracts the output rod 34 in the retracting direction.
[0029]
The set speed detection means 18c is a potentiometer that detects the speed setting position of the speed setting means 18, and transmits a speed setting voltage corresponding to the speed setting position to the controller 16 as a speed setting signal. The speed setting means 18 is a single speed setting unit for both the electronic governor 1 and the mechanical governor 2, and the speed setting means 18 sets the electronic control characteristics and the mechanical control characteristics. Can be set in a series. Further, the speed setting detection means 18c can detect both the setting speed of the electronic governor 1 and the setting speed of the mechanical governor 2. The speed detection unit 15 detects the engine rotation speed N and transmits a speed detection signal to the controller 16. The reference load changing means M includes a switching lever, and changes the reference load by selecting the mode M1 and the mode M2 with the switching lever. The reference load will be described later. The electronic governor 1 includes a metering position detection means 30 that directly detects the fuel metering position of the fuel metering unit 3. This metering position detection means 30 transmits a metering position detection signal of the fuel metering unit 3 to the controller 16.
[0030]
The controller 16 performs the following processing.
The electronic control characteristics are set based on the speed setting signal from the set speed detecting means 18c and the mode selection of the reference load changing means M. In response to the speed detection signal, the rotational deviation between the electronically controlled settling rotational speed NX and the engine rotational speed N determined based on the electronic control characteristics is calculated. The adjustment position detection signal is received, and the duty ratio of the PWM wave is set based on the calculation result of the rotation deviation and the adjustment position. A PWM wave is transmitted to the switching element of the energization circuit that energizes the electromagnetic coil 35 of the actuator 17 to adjust the output of the actuator 17.
[0031]
The setting method and contents of the electronic control characteristics and the mechanical control characteristics are as follows.
When the speed setting of the speed setting means 18 shown in FIG. 1 is set to high speed and the reference load changing means M is set to the mode M1, the control characteristic diagram shown in FIG. 2 is obtained. This control characteristic diagram shows the set rotational speeds of mechanical control and electronic control for the load. The solid line in FIG. 2 indicates the mechanical control characteristic line 50. In the mechanical control characteristic line 50, the inclination line near vertical is the mechanical adjustment line 51, the inclination line near horizontal is the torque-up line 52, and the horizontal line is A full load line 53 is shown. The alternate long and short dash line indicates the electronic governing line 60. The mechanical control characteristics from the rated load L5 to the no-load L1 are droop control characteristics in which the settling rotational speeds n5 to n1 gradually increase as the load decreases. In the rated overload region, the torque-up control characteristic is such that as the load increases, the settling rotational speed n6 becomes lower than the settling rotational speed n5 at the rated load L5. The electronic control characteristics are isochronous control characteristics in which the set rotational speeds NX from the rated overload L6 to the no-load L1 have the same value. Note that the electronic governing line 60 may be set to have a droop control characteristic, similar to the mechanical governing line 51.
[0032]
The relationship between electronic control characteristics and mechanical control characteristics is as follows.
A load at a point where the mechanical control characteristic line 50 and the electronic governing line 60 intersect is defined as a reference load. When the reference load changing means M is set to the mode M1, the rated load L5 becomes the reference load as shown in FIG. The electronically controlled settling rotational speed NX at the rated load L5 serving as the reference load coincides with the mechanically controlled settling rotational speed n5 at the same load L5. Electronically controlled settling speeds NX at partial loads L4 to L1 lower than rated load L5 are lower than mechanically controlled settling speeds n4 to n1 at the same loads L4 to L1, respectively. The torque-up settling rotational speed n6 at the rated overload L6 is lower than the electronically controlled settling rotational speed NX at the same load L6. When a predetermined load is applied to the engine, the control with the slower settling speed relative to the load has priority, and the engine speed is set to the slower settling speed.
[0033]
The setting contents of the engine speed N are as follows.
During engine operation, at the rated load L5 serving as the reference load, the electronic governor 1 and the mechanical governor 2 set the engine rotational speed N to the respective set rotational speeds NX · n5 for electronic control and mechanical control. The set rotational speeds NX · n5 have the same value. In the partial loads L4 to L1 lower than the rated load L5, the electronic governor 1 sets the engine rotational speed N to the electronically controlled settling mechanical rotational speed NX. At the rated overload L6, the mechanical governor 2 lowers the engine rotation speed N to a torque-up rotation speed n6 close to the maximum torque rotation speed NM.
[0034]
The method for setting the engine speed N is as follows.
During the engine operation, at the rated load L5 serving as the reference load, based on the electronic speed control line 60 and the mechanical speed control line 51, the set position of the fuel metering unit 3 by electronic control is equal to the set position by mechanical control. This is the maximum fuel supply position 4 for electronic control by the electronic governor 1 in the area excluding the engine start area 7 (in the case of a diesel engine, it may be called the maximum fuel injection position). In this case, the output unit 9 of the electronic governor 1 receives the electronic input unit 11 of the fuel metering unit 3, and the output unit 10 of the mechanical governor 2 receives the mechanical input unit 12 of the fuel metering unit 3, respectively. Both governors 2 set the fuel metering unit 3 to the electronically controlled maximum fuel supply position 4 and set the engine rotational speed N to the electronically controlled and mechanically controlled set rotational speed NX · n5.
[0035]
In the partial load L4 to the no load L1 lower than the rated load L5 serving as the reference load, only the electronic control is performed in all the regions 5a of the speed control region 5 based on the electronic speed control line 60, and the output part of the electronic governor 1 9 receives the electronic input unit 11 of the fuel metering unit 3, the output unit 10 of the mechanical governor 2 moves away from the mechanical input unit 12 of the fuel metering unit 3 toward the fuel increase side, and the electronic governor 1 departs from the fuel metering unit 3. The engine is set in the region 5a on the fuel reduction side from the electronically controlled maximum fuel supply position 4, and the engine speed N is set to the electronically controlled set speed NX. Note that the speed control area 5 is an area in which speed control is performed based on at least one of the electronic speed control line 60 or the mechanical speed control line 51 in the metering area.
[0036]
At a rated overload L6 higher than the reference load L5, the output unit 10 of the mechanical governor 2 receives the mechanical input unit 12 of the fuel metering unit 3 in the torque up region 6 based on the torque up line 52, and the electronic governor 1 Of the fuel metering unit 3 from the electronic input unit 11 of the fuel metering unit 3 to the fuel boosting side, and the mechanical governor 2 moves the fuel metering unit 3 from the electronically controlled maximum fuel supply position 4 to the torque increasing region 6 on the fuel boosting side. The engine rotational speed N is lowered to the torque-up rotational speed n6.
[0037]
The transient characteristics when the load fluctuates are as follows.
When the load decreases from the rated load L5 as the reference load to the partial load L4 to the no load L1, the output unit 10 of the mechanical governor 2 moves away from the mechanical input unit 12 of the fuel metering unit 3 to the fuel increase side, and the electronic control is mechanical. Control is given priority over control. Conversely, when the load increases from the rated load L5 to the rated overload L6, the output unit 9 of the actuator 17 moves away from the electronic input unit 11 of the fuel metering unit 3 to the fuel increase side, and mechanical control takes precedence over electronic control. Increase the torque. At the time of electronic control, the operation of the mechanical governor 2 is not input as a disturbance element, and at the time of torque increase, the operation of the electronic governor 1 is not input as a disturbance element. Further, the actuator 17 of the electronic governor 1 can be a small and small output.
[0038]
However, due to differences in the settling speed between electronic control and mechanical control, the output part 9 of the electronic governor 1 goes too far to the fuel increase side during the electronic control, or the output part 10 of the mechanical governor 2 operates quickly to the fuel increase side. If not, the mechanical input unit 12 of the fuel metering unit 3 is temporarily received by the output unit 10 of the mechanical governor 2, and the output unit 9 of the electronic governor 1 is separated from the electronic input unit 11 of the fuel metering unit 3. Sometimes. Conversely, if the output part 10 of the mechanical governor 2 goes too far to the fuel increase side during the torque increase, or if the output part 9 of the electronic governor 1 does not operate quickly to the fuel increase side, the fuel metering part 3 The electronic input unit 11 may be received by the output unit 9 of the electronic governor 1, and the output unit 10 of the mechanical governor 2 may be temporarily separated from the mechanical input unit 12 of the fuel metering unit 3.
[0039]
The change method and details of the reference load are as follows.
When the reference load changing means M is switched to the mode M2 while the speed setting means 18 shown in FIG. 1 is set at the high speed position, only the electronic speed regulation line 60 indicated by the one-dot chain line is shifted to the high speed side as shown in FIG. The reference load is changed from the rated load L5 to the height of the partial load L3. In this case, the electronic control settling rotational speed NX at the partial load L3 as a new reference load coincides with the mechanical control settling rotational speed n3 at the same load L3. Electronically controlled settling rotational speeds NX at partial loads L2 to L1 lower than partial loads L3 are lower than mechanically controlled settling rotational speeds n2 to n1 at the same loads L2 to L1, respectively. The mechanical control settling rotational speeds n4 to n6 at the partial load L4 to the rated overload L6 higher than the partial load L3 are lower than the electronically controlled settling rotational speed NX at the same loads L4 to L6, respectively. In this way, the electronically controlled maximum fuel supply position 4 can be changed.
[0040]
The setting contents of the engine speed N are as follows.
During engine operation, at the partial load L3 serving as the reference load, both the electronic governor 1 and the mechanical governor 2 perform electronic control of the fuel metering unit 3 based on the electronic governing line 60 and the mechanical governing line 51. The maximum fuel supply position 4 is set, and the engine rotational speed N is set to the electronic control and mechanical control set rotational speed NX · n3. In the partial load L2 to no-load L1 lower than the partial load L3, the electronic governor 1 is a region on the fuel reduction side of the electronically controlled maximum fuel supply position 4 in the speed adjusting region 5 based on the electronic speed control line 60. In 5a, the fuel metering unit 3 is set, and the engine speed N is set to the electronically controlled set speed NX. At a partial load L4 to a rated load L5 that is higher than the partial load L3, the mechanical governor 2 moves the fuel metering unit 3 in the region 5b on the fuel increase side from the maximum fuel supply position 4 of electronic control based on the mechanical speed regulation line 51. Then, the engine rotational speed N is set to mechanically controlled rotational speeds n4 to n5. In this case, since the maximum fuel supply position 4 of the fuel metering unit 3 in the electronic control is in the middle of the speed adjusting region 5 of the fuel metering unit 3, electronic control and mechanical control are automatically performed at the maximum fuel supply position 4. Switch. In the rated overload L6, the mechanical governor 2 increases the torque based on the torque-up line 52. In this case, since the light load L2 to the no-load L1 are set by electronic control, hunting is less likely to occur compared to mechanical control even if the biasing spring force 13a is reduced. Therefore, a small and small output actuator 17 can be used.
[0041]
The transient characteristics when the load fluctuates are as follows.
When the load decreases from the partial load L3 serving as the reference load to the partial load L2 to the no-load L1, the electronic control performs control with priority over the mechanical control. Conversely, when the load increases from the partial load L3 serving as the reference load to the partial load L4 to the rated load L5, the mechanical control performs control with priority over the electronic control. When the load increases from the loads L1 to L2 lower than the partial load L3 serving as the reference load to the rated overload L6, the electronic control is first performed with priority over the mechanical control. Priority is given to control. For the same reason as when the reference load is the rated load L5, the mechanical input unit 12 of the fuel metering unit 3 is received by the output unit 10 of the mechanical governor 2 during the electronic control, and the fuel metering unit during the mechanical control. 3 may be received by the output unit 9 of the electronic governor 1.
[0042]
The speed setting changing method and the changing contents are as follows.
When the speed setting of the speed setting means 18 is changed from high speed to low speed while the reference load changing means M shown in FIG. 1 is set to the mode M1, as shown in FIG. 4, an electronic speed regulation line 60 indicated by a one-dot chain line and a solid line Each of the mechanical speed adjustment lines 51 shown in FIG. Further, when the speed setting of the speed setting means 18 is changed from high speed to low speed while the reference load changing means M is set to the mode M2, as shown in FIG. 5, it is indicated by an electronic speed regulation line 60 indicated by a one-dot chain line and a solid line. All of the mechanical adjustment lines 51 move in parallel to the low speed side. If the speed setting of the speed setting means 18 is greatly shifted from the high speed to the low speed side, the torque-up characteristic disappears.
[0043]
The method of limiting the engine speed N and the details of the limitation are as follows.
When the reference load changing means M shown in FIG. 1 is set to the mode M2 and the speed setting means 18 is set to a high speed, as shown in FIG. 3, the electronically controlled settling rotation at the partial load L3 serving as the reference load is performed. The speed NX exceeds the rated engine speed NT. In this case, when the speed limit switch 29 shown in FIG. 1 is turned on, the controller 16 changes the reference load from the partial load L3 to the rated load L5 as shown in FIG. In this case, the electronic governor 1 sets the engine rotational speed N to the same as the rated rotational speed NT, and the electronically controlled settling rotational speed NX ′ at the rated load L5 to the no-load L1 that is the rated load L5 or less that becomes a new reference load during engine operation. When the rated overload L6 exceeds the rated load L5 that becomes the new reference load, the mechanical governor 2 reduces the engine speed N to a torque-up speed n6 that is lower than the rated speed NT.
[0044]
The setting method and setting contents of mechanical single control are as follows.
When the electronic operation stop switch 31 shown in FIG. 1 is turned on, the output unit 9 of the actuator 17 stops at an operation stop position 17a that is out of the operation range of the electronic input unit 11 of the fuel metering unit 3 to the fuel increase side. In this case, the combined control of electronic control and mechanical control is switched to mechanical single control shown in FIG.
[0045]
The configuration for stopping the engine is as follows.
As shown in FIG. 1, the fuel supply apparatus includes a manual engine stop means 27. The engine stop means 27 includes a stop operation lever 27a and a stop output portion 27b. The stop output part 27b is cylindrical and is inserted into the guide hole 28a of the engine machine wall 28 so as to be able to advance and retreat, and the tip thereof faces the electronic input part 11 of the fuel metering part 3. When the stop output lever 27b is pushed to the fuel reduction side by the stop operation lever 27a, its tip comes into contact with the electronic input portion 11, and the fuel metering portion 3 is moved to the fuel supply stop position 8 against the biasing spring force 13a. Press until Further, the fuel metering unit 3 can be pushed to the fuel supply stop position 8 by the actuator 17. This eliminates the need for a dedicated circuit for the engine stop device and a dedicated actuator. Since the output portion 9 of the actuator 17 is urged by the spring 33, if the energization of the actuator 17 is canceled due to the failure of the electronic governor 1, the fuel adjustment is performed by the output portion 9 by the urging force of the spring 33. Push the amount part 3 to the fuel supply stop position 8 and keep it there. In this case, since the engine cannot be restarted, the failure of the electronic governor 1 can be confirmed.
[0046]
The electronic governor 1 has the following correction function.
When the electronic governor 1 is not in the cold start, the fuel supply amount is corrected to be smaller than that in the cold start. Therefore, as shown in FIG. 1, the electronic governor 1 includes a temperature detection means 37. When the detected engine temperature exceeds a predetermined value, the electronic governor 1 reduces the fuel supply amount in the engine start region 7 as compared with the case where the detected engine temperature is lower than the predetermined value. That is, the fuel metering unit 3 is held at the start increase limit position 7a. The engine temperature can be detected by detecting the engine wall temperature, the engine coolant temperature, and the engine oil temperature. The determination of whether or not the engine is cold start can also be made by detecting the outside air temperature around the engine. In this case, generation of black smoke and useless consumption of fuel can be suppressed.
[0047]
Further, the electronic governor 1 includes an intake boost pressure detecting means 38 and a boucon function for limiting and correcting the fuel supply amount until the pressure of the supercharged intake air is sufficiently increased. Further, the electronic governor 1 includes an atmospheric pressure detection unit 39, and has a high altitude correction function for correcting a decrease in the fuel supply amount when the atmospheric pressure is low. Further, the electronic governor 1 is provided with the operation speed detection means 40, and when the operation speed of the speed setting means 18 is too high, the operation speed of the output section 9 is suppressed and the overshoot of the fuel metering section 3 is suppressed. It has a function to do.
FIG. 8 shows a first modification of the first embodiment. In this first modification, the speed setting of the speed setting means 18 shown in FIG. 1 is set to high speed, and the reference load changing means M is set to mode M1. Then, the electronic governing line 60 indicated by a chain line in FIG. 8 crosses the upper limit of the torque up line 52 at the position of the maximum load L7. FIG. 9 shows a second modification of the first embodiment. In this second modification, the speed setting means 18 shown in FIG. 1 is set to a low speed, and the reference load changing means M is set to the mode M1. Then, as shown in FIG. 9, when the electronic control settling rotational speed NX is lower than the maximum torque rotational speed NM at the no-load L1 to the rated overload L6, the controller 16 converts the isochronous control characteristics to the droop control characteristics. As the load increases, the electronically controlled settling rotational speed NX approaches the maximum torque rotational speed NM.
[0048]
A second embodiment will be described.
FIGS. 10-12 is a figure explaining the fuel supply apparatus of the diesel engine which concerns on 2nd Embodiment. The second embodiment is different from the first embodiment in the following points.
As shown in FIG. 10, the speed setting means 18 is composed of a speed setting means 18a of the electronic governor 1 and a speed setting means 18b of the mechanical governor 2, and the speed setting of each of these speed setting means 18a and 18b By setting the control characteristics and the mechanical control characteristics individually, the height of the reference load can be set freely.
[0049]
A pedal is used as the speed setting means 18 b of the mechanical governor 2 and is connected to the interlocking rod 22. When the locking lever 24 is provided near the interlocking rod 22, the speed setting means 18b is moved to an arbitrary setting position, and then the interlocking rod 22 is locked by the locking lever 24, the speed setting means 18b is moved from the setting position. Does not return to the low speed side. The speed setting means 18a of the electronic governor 1 is a manual lever, and this speed setting position is detected by the set speed detection means 18c. Since the reference load changing means M becomes unnecessary, it is not provided. Other configurations are the same as those of the first embodiment. 10 to 12, the same elements as those in the first embodiment are denoted by the same reference numerals.
[0050]
The setting method and setting contents of the electronic control characteristics and the mechanical control characteristics are as follows.
When both speed setting means 18a and 18b are set to high speed, the same composite control characteristics as in FIG. 2 can be obtained, and high speed operation with the rated load L5 set as the reference load can be performed. If only the speed setting means 18a of the electronic governor 1 is shifted slightly from this state to the high speed side, the same composite control characteristics as in FIG. 3 can be obtained, and high speed operation with the partial load L3 set as the reference load can be performed.
[0051]
When both speed setting means 18a and 18b are set to low speed, the same composite control characteristics as in FIG. 4 can be obtained, and low speed operation with the rated load L5 set as the reference load can be performed. From this state, if only the speed setting means 18 of the electronic governor 1 is shifted slightly to the high speed side, the same composite control characteristics as in FIG. 5 can be obtained, and low speed operation with the partial load L3 set as the reference load can be performed. By combining various speed settings of the respective speed setting means 18a and 18b, various composite control characteristics that make the speed setting different from the reference load can be obtained.
[0052]
When the speed setting of the speed setting means 18a of the electronic governor 1 is made high and the speed setting of the speed setting means 18b of the mechanical governor 2 is made low, as shown in FIG. 11, the mechanical control with no load L1 to overload L6 is performed. Since the settling rotational speeds n1 to n6 are lower than the electronic control settling rotational speed NX at the same loads L1 to L6, electronic control is not performed, and the combined control of electronic control and mechanical control is switched to mechanical single control. be able to.
[0053]
The speed setting means 18a of the electronic governor 1 is set to a low speed, the speed setting means 18b of the mechanical governor 2 is set to a high speed, and as shown in FIG. 12, electronic control with no load L1 to rated overload L6 is performed. If the settling rotational speed NX of the engine becomes lower than the maximum torque rotational speed NM, the controller 16 changes the isochronous control characteristic to the droop control characteristic, and as the load increases, the electronically controlled settling rotational speed NX becomes the maximum torque rotational speed. Approach the speed NM.
[Brief description of the drawings]
FIG. 1 is a schematic diagram of an electronic governor and a mechanical governor according to the first embodiment.
FIG. 2 is a control characteristic diagram in mode M1 during high-speed setting according to the first embodiment.
FIG. 3 is a control characteristic diagram in mode M2 during high-speed setting according to the first embodiment.
FIG. 4 is a control characteristic diagram in mode M1 at the time of low speed setting according to the first embodiment.
FIG. 5 is a control characteristic diagram in mode M2 at the time of low speed setting according to the first embodiment.
FIG. 6 is a control characteristic diagram when speed is limited according to the first embodiment.
FIG. 7 is a control characteristic diagram during mechanical single control of the first embodiment.
FIG. 8 is a control characteristic diagram in mode M1 during high-speed setting according to a first modification of the first embodiment.
FIG. 9 is a control characteristic diagram in mode M1 during low speed setting according to a second modification of the first embodiment.
FIG. 10 is a schematic diagram of an electronic governor and a mechanical governor according to the second embodiment.
FIG. 11 is a control characteristic diagram during mechanical single control of the second embodiment.
FIG. 12 is a control characteristic diagram during droop control according to the second embodiment.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 ... Electronic governor, 2 ... Mechanical governor, 3 ... Fuel metering part, L6-L1 ... Load, NX ... Electronic control settling rotational speed, n6-n1 ... Mechanical control settling rotational speed, N ... Engine rotational speed, 18 ... speed setting means, 18a ... speed setting means for electronic governor, 18b ... speed setting means for mechanical governor governor, M ... reference load changing means, NT ... rated rotational speed.

Claims

The electronic governor (1) and the mechanical governor (2) are provided, and the electronic control by the electronic governor (1) is the maximum in the metering region of the fuel metering unit (3) except the engine start region (7). Limit the fuel supply with the mechanical governor (2),
By setting the electronic control characteristics by the electronic governor (1) and the mechanical control characteristics by the mechanical governor (2) by setting the speed of the speed setting means (18), the fuel metering is performed at a predetermined reference load (L5). The means (3) is positioned at the electronically controlled maximum fuel supply position (4), and the electronic control settling rotational speed (L4) to (L1) lower than the predetermined reference load (L5) ( NX) is lower than the mechanical control settling speeds (n4) to (n1) at the same load (L4) to (L1), and the engine load is lower than the reference load (L5) during engine operation. In (L4) to (L1), the electronic governor (1) sets the engine rotational speed (N) to the electronically controlled settling rotational speed (NX).

The fuel supply device for an engine according to claim 1,
In the loads (L4) to (L1) lower than the reference load (L5), the settling rotational speed (NX) of the electronic control at each load (L4) to (L1) is set to the same value. An engine fuel supply device.

The fuel supply device for an engine according to claim 1 or 2,
By changing the speed of the single speed setting means (18), the electronic speed control line (60) and the mechanical speed control line (51) representing the electronic control characteristics and the mechanical control characteristics are successively arranged in the increasing / decreasing direction of the engine speed. A fuel supply device for an engine, wherein the control characteristics can be changed so as to slide.

The engine fuel supply device according to any one of claims 1 to 3,
A fuel supply apparatus for an engine, wherein the reference load changing means (M) can change the reference load (L5) to another reference load (L3) having a different height.

The engine fuel supply device according to any one of claims 1 to 4,
The speed setting means (18) comprises a speed setting means (18a) of the electronic governor (1) and a speed setting means (18b) of the mechanical governor (2). These speed setting means (18a) and (18b) A fuel supply device for an engine, wherein the reference load height can be freely set by individually setting the electronic control characteristic and the mechanical control characteristic at the speed setting.

The engine fuel supply device according to any one of claims 1 to 5,
When the set speed (NX) of electronic control at the reference load (L3) is set to a value exceeding the rated speed (NT) of the engine in the speed setting of the speed setting means (18), the electronic governor (1) changes the reference load (L3) to a new reference load (L5) higher than this,
During engine operation, the electronic governor (1) performs electronically controlled settling rotation with the engine speed (N) equal to or lower than the rated speed (NT) when the load (L5) to (L1) is less than the new reference load (L5). When the load (L6) exceeds the new reference load (L5), the mechanical governor (2) limits the engine speed (N) to a speed equal to or lower than the rated speed (NT). An engine fuel supply apparatus characterized by the above.

In a fuel supply apparatus for an engine, comprising an electronic governor (1) and a mechanical governor (2), and performing electronic control by the electronic governor (1) and mechanical control by the mechanical governor (2).
By setting the electronic control characteristic and the mechanical control characteristic by the speed setting of the speed setting means (18), the electronic control settling rotation at loads (L4) to (L1) lower than the predetermined reference load (L5) The speed (NX) is set to be lower than the set rotational speeds (n4) to (n1) of the mechanical control at the same load (L4) to (L1), respectively.
During engine operation, at a load (L6) higher than the reference load (L5), the mechanical governor (2) sets the engine rotational speed (N) to a mechanically controlled set rotational speed (n6),
In the loads (L4) to (L1) lower than the reference load (L5), the electronic governor (1) sets the engine speed (N) to the electronically controlled settling speed (NX). An engine fuel supply device.

The fuel supply device for an engine according to claim 7,
In the loads (L4) to (L1) lower than the reference load (L5), the settling rotational speed (NX) of the electronic control at each load (L4) to (L1) is set to the same value. An engine fuel supply device.

The fuel supply device for an engine according to claim 7 or 8,
A fuel supply device for an engine, characterized in that a series of electronic control characteristics and mechanical control characteristics can be set by speed setting of a single speed setting means (18).

The fuel supply apparatus for an engine according to claim 9,
A fuel supply apparatus for an engine, wherein the reference load changing means (M) can change the reference load (L5) to another reference load (L3) having a different height.

The fuel supply device for an engine according to claim 7 or 8,
The speed setting means (18) comprises a speed setting means (18a) of the electronic governor (1) and a speed setting means (18b) of the mechanical governor (2). These speed setting means (18a) and (18b) A fuel supply device for an engine, wherein the reference load height can be freely set by individually setting the electronic control characteristic and the mechanical control characteristic at the speed setting.

The fuel supply apparatus for an engine according to any one of claims 7 to 11,
When the set speed (NX) of electronic control at the reference load (L3) is set to a value exceeding the rated speed (NT) of the engine in the speed setting of the speed setting means (18), the electronic governor (1) changes the reference load (L3) to a new reference load (L5) higher than this,
During engine operation, the electronic governor (1) performs electronically controlled settling rotation with the engine speed (N) equal to or lower than the rated speed (NT) when the load (L5) to (L1) is less than the new reference load (L5). At the load (L6) that is set to the speed (NX ') and exceeds the new reference load (L5), the mechanical governor (2) sets the engine speed (N) below the rated speed (NT). A fuel supply device for an engine characterized by being set to a rotational speed (n6).