JP2004345446A

JP2004345446A - Traveling control device for vehicle

Info

Publication number: JP2004345446A
Application number: JP2003143391A
Authority: JP
Inventors: Tsutomu Sasaki; 勉佐々木
Original assignee: UD Trucks Corp
Current assignee: UD Trucks Corp
Priority date: 2003-05-21
Filing date: 2003-05-21
Publication date: 2004-12-09
Anticipated expiration: 2023-05-21
Also published as: JP4334277B2

Abstract

<P>PROBLEM TO BE SOLVED: To provide a traveling control device for a vehicle that ensures a good start even in case of a single-axle rear-wheel-drive vehicle. <P>SOLUTION: This traveling control device comprises vehicle height detecting means 31a and 31b for detecting the vehicle height level at a front axle 20 side and a rear axle 22 side, axle load detecting means 32a and 32b for detecting the axle load of the front axle 20 and the rear axle 22, slip detecting means 35 and 36 for detecting the slip state of a driving wheel 34, and a start control means 30 that controls valve means 26a and 26b for extending or contracting air suspensions 23a and 23b so as to apply a dynamic load to the driving wheel 34 based on the vehicle height level at the front axle 20 side and the rear axle 22 side and the axle load of the front axle 20 and the rear axle 22 in case that a slip state of the driving wheel 34 is occurred at the starting, and controls the valve means 26a and 26b for bringing back to the original vehicle height level after starting. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

【０００１】
【発明の属する技術分野】
この発明は、車両の走行制御装置に関する。
【０００２】
【従来の技術】
従来、車両のサスペンションに乗り心地を向上するためにエアサスペンションを用いるものがある。
【０００３】
大型車両のように、後輪２軸のうち、一方（例えば後前軸）を駆動軸、もう一方（例えば後後軸）を従動軸としたものは、駆動軸の荷重（軸重）が小さすぎる場合、走行に影響するため、駆動軸のエアサスペンションの空気圧を相対的に高くして、駆動軸の荷重分担を大きくするようにしている。
【０００４】
したがって、積載量等が少なく、滑りやすい路面（低摩擦係数路面）や登坂路面にて発進するとき等、駆動力が低下することなく、またスリップを抑えて、発進できるようになっている（特許文献１〜３）。
【０００５】
【特許文献１】
特開平９−１０９６４５号
【特許文献２】
特開平９−２０２１２３号
【特許文献３】
特開２００１−２１３１３０
【０００６】
【発明が解決しようとする課題】
このような軸重配分は、後輪２軸車にあっては行えるが、前輪１軸、後輪１軸の車両には適用できない。
【０００７】
後輪１軸車の場合にも、積載量等が少なく、滑りやすい路面や登坂路面にて発進する際は、駆動力が低下したり、スリップが発生して、良好な発進を得にくいことがあるが、駆動軸のエアサスペンションの空気圧を相対的に高くしても、荷重分担は変わるわけではない。
【０００８】
この発明は、このような課題に注目してなされたものであり、駆動輪に動的荷重を付与して、後輪１軸車でも良好な発進を確保し得る車両の走行制御装置を提供することを目的とする。
【０００９】
【課題を解決するための手段】
第１の発明は、前車軸ならびに後車軸に備えるエアサスペンションに対して、エアタンクからエアサスペンションへの所定圧のエアの供給とエアサスペンションのエアの排出とを行う弁手段を備える車両において、前車軸側および後車軸側の車高レベルを検出する車高検出手段と、前車軸および後車軸の軸重を検出する軸重検出手段と、駆動輪のスリップ状態を検出するスリップ検出手段とを備え、発進時に、前車軸側および後車軸側の車高レベルと、前車軸および後車軸の軸重とに基づき、駆動輪のスリップ状態を生じた場合、駆動輪に動的荷重を付与するべく駆動車軸のエアサスペンションを伸動もしくは縮動するよう弁手段を制御すると共に、発進後は、元の車高レベルに戻すように弁手段を制御する発進制御手段を備える。
【００１０】
第２の発明は、前車軸ならびに後車軸に備えるエアサスペンションに対して、エアタンクからエアサスペンションへの所定圧のエアの供給とエアサスペンションのエアの排出とを行う弁手段を備える車両において、前車軸側および後車軸側の車高レベルを検出する車高検出手段と、前車軸および後車軸の軸重を検出する軸重検出手段と、登坂路を検出する登坂路検出手段とを備え、登坂路の発進時に、前車軸側および後車軸側の車高レベルと、前車軸および後車軸の軸重とに基づき、駆動輪に動的荷重を付与するべく駆動車軸のエアサスペンションを伸動もしくは縮動するよう弁手段を制御すると共に、発進後は、元の車高レベルに戻すように弁手段を制御する発進制御手段を備える。
【００１１】
第３の発明は、第１、第２の発明において、前記発進制御手段は、駆動車軸以外のエアサスペンションを駆動車軸のエアサスペンションと反対方向に動作するように弁手段を制御する。
【００１２】
第４の発明は、第１〜第３の発明において、エンジンならびに回転電機によって走行可能な車両にあって、前記発進制御手段の制御は、回転電機の出力のみによる発進時およびエンジンの出力と回転電機の出力を併用しての発進時に実行する。
【００１３】
【発明の効果】
第１の発明においては、発進時に駆動輪のスリップ状態を生じた場合、前車軸側および後車軸側の車高レベルと、前車軸および後車軸の軸重とに基づき、駆動輪に動的荷重が付与され、接地圧が瞬時的に高まって、発進が行われる。したがって、滑りやすい路面にて発進する場合、スリップによる駆動力の低下を抑えて、積載量に合った発進を行え、良好な発進を得ることができる。
【００１４】
第２の発明においては、登坂路の発進時に、前車軸側および後車軸側の車高レベルと、前車軸および後車軸の軸重とに基づき、駆動輪に動的荷重が付与され、発進が行われる。したがって、登坂路にて発進する場合、スリップによる駆動力の低下を抑えて、積載量に合った発進を行え、良好な発進を得ることができる。
【００１５】
第３の発明においては、駆動輪の動的動作をアシストできる。
【００１６】
第４の発明においては、ハイブリッド車両において回転電機の出力の変化によるスリップを抑制して発進を行える。
【００１７】
【発明の実施の形態】
図１は、前輪１軸（前車軸：遊動輪）、後輪１軸（後車軸：駆動輪）のハイブリッド車両におけるシステム構成図を示す。
【００１８】
図１において、１はエンジン、２はインバータ３を備える回転電機（モータジェネレータ）であり、エンジン１ならびに回転電機２はそれぞれクラッチ４、５を介して変速機６に連結され、変速機６の出力は後車軸２２の駆動輪３４に伝達される。
【００１９】
エンジン１は、ディーゼルエンジン（または圧縮天然ガスを燃料とするＣＮＧエンジン）が採用される。回転電機２は、高効率および小形軽量化の面から、永久磁石型同期電動機（ＩＰＭ同期モータ）が使用される。
【００２０】
エンジン１、回転電機２、クラッチ４、５、変速機６は、車両コントロールユニット１０によって、アクセルペダルの踏み量（アクセル操作量：アクセル開度）、エンジン１の回転速度、回転電機２の回転速度、車速、ブレーキペダル１１の踏み量、蓄電装置１２のＳＯＣ（ｓｔａｔｅｏｆｃｈａｇｅ）等に基づいて制御される。
【００２１】
蓄電装置１２には、ブレーキエネルギを短時間で無駄なく高効率に回生するため、車両の電池許容質量に対して必要な出力密度を確保しやすい、電気二重層キャパシタが使用される。
【００２２】
車両コントロールユニット１０は、蓄電装置１２のＳＯＣをパラメータに、所定の制御マップに回転電機２の出力とエンジン１の出力との分担比を設定してあり、その制御マップから蓄電装置１２のＳＯＣに応じた出力分担比を求め、この分担比と要求駆動力（アクセル操作量）に基づいて、回転電機２の出力およびエンジン１の出力を制御する。
【００２３】
回転電機２の出力分担比＝１（エンジン１の出力分担比＝０）の場合、クラッチ４を切断した状態（クラッチ５は接続）において、アクセル操作量に相当する出力が回転電機２から得られるようにインバータ３を制御する。回転電機２の出力分担比＜１（エンジン１の出力分担比＞０）の場合、クラッチ４を接続した状態において、蓄電装置１２のＳＯＣの低下に連れて回転電機２の分担出力が小さくなり、それに応じてエンジン１の分担出力が大きくなるようにエンジン１の出力およびインバータ３を制御する。エンジン１の出力分担比＝１（回転電機２の出力分担比＝０）の場合、アクセル操作量に相当する出力がエンジン１から得られるようにエンジン１の出力を制御する。
【００２４】
また、アクセルを解放する減速時に、蓄電装置１２への充電が可能な限り、クラッチ４を切断した状態において、回転電機２の発電（回生発電）を行うようにインバータ３を制御する。サービスブレーキ時は、ブレーキペダル１１の踏み量（要求制動力）に基づいて、蓄電装置１２への充電が可能な限り、クラッチ４を切断した状態において、回転電機２の発電（回生発電）を行うようにインバータ３を制御する。
【００２５】
車両の発進に際しては、キースイッチがＳＴ（スタート）に入ると、エンジン１が始動され、クラッチ４が断かつエンジン１がアイドル運転の停車状態において、蓄電装置１２のＳＯＣ等を基に発進モードが選択される。
【００２６】
回転電機２の単独発進の場合、クラッチ５が接続された状態（変速機６は発進段にシフト）で、アクセルペダルの踏み込みにしたがって、回転電機２が要求駆動力を発生するように制御され、車両は走り始めることになる。
【００２７】
エンジン１の出力と回転電機２の出力との併用発進の場合、クラッチ５が接続された状態（変速機６は発進段にシフト）で、アクセルペダルの踏み込みにしたがって、クラッチ４が接続されると共にエンジン１および回転電機２がそれぞれの分担出力を発生するように制御され、車両は走り始めることになる。
【００２８】
エンジン１の単独発進の場合、クラッチ５が切断された状態（変速機６は発進段にシフト）で、アクセルペダルの踏み込みにしたがって、クラッチ４が接続されると共にエンジン１が要求駆動力を発生するように制御され、車両は走り始めることになる。
【００２９】
一方、車両の前車軸２０と車体との間にエアサスペンション２１ａ、２１ｂが、後車軸（駆動軸）２２と車体との間にエアサスペンション２３ａ、２３ｂが設けられる。
【００３０】
エアサスペンション２１ａ、２１ｂ、２３ａ、２３ｂのベローズ（エアスプリング）に対して、それぞれエアリザーバタンク２４からベローズへの所定圧のエアの供給とベローズのエアの排出とを行うソレノイドバルブ２５ａ、２５ｂ、２６ａ、２６ｂが設けられる。
【００３１】
ソレノイドバルブ２５ａ、２５ｂ、２６ａ、２６ｂは、エアサスコントロールユニット３０によって、前車軸２０側、後車軸（駆動軸）２２側の車高レベルを検出する車高センサ３１ａ、３１ｂの検出信号、エアサスペンション２１ａ、２１ｂ、２３ａ、２３ｂのベローズの内圧（前車軸２０、後車軸２２の軸重）を検出する内圧センサ３２ａ、３２ｂの検出信号、車両コントロールユニット１０の情報（停車、発進、走行等）、ブレーキペダル１１の踏み込み、各車輪（前輪３３、後輪３４）の回転速度を検出する車輪速センサ３５、３６の検出信号、登坂路を検出する傾斜センサ３７の検出信号、車高レベル操作スイッチ（図示しない）の信号等に基づいて制御される。
【００３２】
エアサスコントロールユニット３０は、車高レベル操作スイッチによる要求レベルに前車軸２０側、後車軸（駆動軸）２２側の車高レベルを設定するようにソレノイドバルブ２５ａ、２５ｂ、２６ａ、２６ｂを制御する。
【００３３】
車両の発進時には、駆動輪（後輪３４）のスリップ状態を生じた場合あるいは登坂路の場合、前車軸２０側、後車軸（駆動軸）２２側の車高レベル、エアサスペンション２１ａ、２１ｂ、２３ａ、２３ｂのベローズの内圧（前車軸２０、後車軸２２の軸重）等に基づいて、駆動輪（後輪３４）にエアサスペンション２３ａ、２３ｂの伸び方向あるいは縮方向に動的荷重を付与するようにソレノイドバルブ２６ａ、２６ｂ等を制御する。
【００３４】
図２は、発進時の制御機能のブロック構成（駆動輪のスリップに対して）を表すものであり、要求駆動トルク算出手段４０、回転電機２の回転加速度を算出する手段４１、回転電機２の駆動軸の慣性トルクを算出する手段４２、駆動輪のスリップ状態を判定する手段４３、回転電機２のトルク値を補正して出力する手段４４、前車軸２０側、後車軸（駆動軸）２２側の車高レベルを判定する手段４５、エアサスペンション２１ａ、２１ｂ、２３ａ、２３ｂのベローズの内圧より前車軸２０、後車軸２２の軸重（配分）を判定する手段４６、動的荷重を選択する手段４７が備えられる。
【００３５】
要求トルク算出手段４０は、アクセル開度と車速とから要求駆動トルクを算出する。回転電機２の要求駆動トルクは蓄電装置１２のＳＯＣに基づく出力分担比によって設定する。
【００３６】
駆動輪のスリップ判定手段４３は、各車輪（前輪３３、後輪３４）の回転速度より駆動輪３４のスリップ状態を判定する。
【００３７】
発進時に、回転電機トルク値補正出力手段４４は、回転電機２が出力分担比の要求駆動トルクを発生するようにトルク指令値をインバータ３へ出力する。
【００３８】
発進時に、動的荷重選択手段４７は、駆動輪３４のスリップ状態が検出された場合、前車軸２０側、後車軸（駆動軸）２２側の車高レベル（発進前の値）と、前車軸２０、後車軸２２の軸重（発進前の値）とに基づき、駆動輪（後輪３４）に動的荷重を付与するべくエアサスバルブ（ソレノイドバルブ）２５ａ、２５ｂ、２６ａ、２６ｂを制御するように、エアスプリングバルブ制御手段４８に指令する。
【００３９】
この場合、前車軸２０側、後車軸（駆動軸）２２側の車高レベルが所定レベル以下のときは、後車軸２２のエアサスペンション２３ａ、２３ｂのベローズへエアリザーバタンク２４から所定圧のエアを瞬時的に供給するようにエアスプリングバルブ制御手段４８に指令する。同時に、前車軸２０のエアサスペンション２１ａ、２１ｂのベローズのエアの瞬時的な排出動作を行う。
【００４０】
また、前車軸２０、後車軸２２の軸重が所定値以下で、前車軸２０側、後車軸（駆動軸）２２側の車高レベルが所定レベルを越えているときは、後車軸２２のエアサスペンション２３ａ、２３ｂのベローズのエアの瞬時的な排出動作を行うようにエアスプリングバルブ制御手段４８に指令する。
【００４１】
駆動輪３４のスリップ状態が検出されなくなると、前車軸２０側、後車軸（駆動軸）２２側の車高レベルを元の車高レベルに戻すように、エアスプリングバルブ制御手段４８に指令する。
【００４２】
エンジン制御手段５０は、エンジン１の出力分担比を基にエンジン１の出力を制御する。また、走行中、駆動輪（後輪３２）のスリップ状態を生じた場合、エンジン出力補正手段５１の補正指令に基づきエンジン１の出力を下げるように制御する。
【００４３】
トランスミッション制御手段５２は、ギヤ変速制御手段５３からの指令に基づき変速機６をシフトする。ギヤ変速制御手段５３は、走行中、駆動輪（後輪３２）のスリップ状態を生じた場合、変速を禁止する。
【００４４】
図３は、エアサスコントロールユニット３０の発進制御のフローチャートを示す。
【００４５】
Ｓ１においては、ハイブリッド車両のシステムの起動条件信号を読み込む。
【００４６】
Ｓ２においては、発進条件が成立しているかを判定する。
【００４７】
Ｓ３においては、発進条件が成立している場合、エアサスペンション２１ａ、２１ｂ、２３ａ、２３ｂのベローズの内圧より前車軸２０、後車軸２２の軸重を演算する。
【００４８】
Ｓ４においては、車両の発進状態かを見る。回転電機２の単独発進の場合、クラッチ５が接続された状態（変速機６は発進段にシフト）で、アクセルペダルが踏み込まれた状態か、エンジン１の出力と回転電機２の出力との併用発進の場合、クラッチ５が接続された状態（変速機６は発進段にシフト）で、アクセルペダルが踏み込まれて、クラッチ４が接続された状態（半クラッチを含む）か、エンジン１の単独発進の場合、クラッチ５が切断された状態（変速機６は発進段にシフト）で、アクセルペダルが踏み込まれて、クラッチ４が接続された状態（半クラッチを含む）かを見る。
【００４９】
Ｓ５においては、駆動輪３４のスリップがあるかどうかを見る。
【００５０】
駆動輪３４のスリップがある場合、Ｓ６において前車軸２０側、後車軸（駆動軸）２２側の車高レベルを見る。
【００５１】
Ｓ７においては、前車軸２０側、後車軸（駆動軸）２２側の車高レベルが所定レベル以下のときは、後車軸２２のエアサスペンション２３ａ、２３ｂのベローズへエアリザーバタンク２４から所定圧のエアを瞬時的に供給するようにソレノイドバルブ２６ａ、２６ｂを制御する。同時に、前車軸２０のエアサスペンション２１ａ、２１ｂのベローズのエアの瞬時的な排出動作を行うようにソレノイドバルブ２５ａ、２５ｂを制御する。
【００５２】
また、前車軸２０、後車軸２２の軸重が所定値以下で、前車軸２０側、後車軸（駆動軸）２２側の車高レベルが所定レベルを越えているときは、後車軸２２のエアサスペンション２３ａ、２３ｂのベローズのエアの瞬時的な排出動作を行うようにソレノイドバルブ２６ａ、２６ｂを制御する。
【００５３】
Ｓ８において、駆動輪３４のスリップがなくなると、Ｓ９において、前車軸２０側、後車軸（駆動軸）２２側の車高レベルを元の車高レベルに戻すように、ソレノイドバルブ２５ａ、２５ｂ、２６ａ、２６ｂを制御する。
【００５４】
一方、Ｓ４において、登坂路での発進状態かを見て、登坂路での発進状態の場合、駆動輪３４のスリップに関わらず、Ｓ６以降の処理を行う。
【００５５】
このように構成したため、発進時に駆動輪３４のスリップ状態を生じた場合、前車軸２０側、後車軸（駆動軸）２２側の車高レベルと、前車軸２０、後車軸２２の軸重とに基づき、瞬時的に後車軸２２のエアサスペンション２３ａ、２３ｂが伸動もしくは縮動される。
【００５６】
すなわち、駆動輪（後輪３４）に動的荷重が付与され、これによって接地圧が瞬時的に高まって、変速機６を介して伝えられる駆動力によって、発進が行われる。
【００５７】
この場合、前車軸２０側、後車軸（駆動軸）２２側の車高レベルが所定レベル以下のときは、後車軸２２のエアサスペンション２３ａ、２３ｂのベローズへのエア供給によるエアサスペンション２３ａ、２３ｂの瞬時的な伸動によって、駆動輪（後輪３４）が路面に押圧動される。同時に前車軸２０のエアサスペンション２１ａ、２１ｂのベローズのエア排出によって駆動輪（後輪３４）の押圧動がアシストされる。
【００５８】
また、前車軸２０、後車軸２２の軸重が所定値以下で、前車軸２０側、後車軸（駆動軸）２２側の車高レベルが所定レベルを越えているときは、後車軸２２のエアサスペンション２３ａ、２３ｂのベローズのエア排出によるエアサスペンション２３ａ、２３ｂの縮動に対する反動によって、駆動輪（後輪３４）が路面に押圧動される。
【００５９】
一方、登坂路での発進の場合は、前車軸２０側、後車軸（駆動軸）２２側の車高レベルと、前車軸２０、後車軸２２の軸重とに基づき、前述のように駆動輪（後輪３４）に動的荷重が付与され、変速機６を介して伝えられる駆動力によって、発進が行われる。
【００６０】
したがって、滑りやすい路面や登坂路にて発進する場合、スリップによる駆動力の低下を抑えて、積載量に合った発進を行え、路面状態、積載状態に対する高度な運転技術を必要とせず、良好な発進を得ることができる。
【００６１】
この発進時のエアサスペンション２１ａ、２１ｂ、２３ａ、２３ｂの制御は、特に回転電機２の単独発進の場合およびエンジン１の出力と回転電機２の出力との併用発進の場合に行うようにして良い。
【００６２】
ハイブリッド車両において、回転電機２の出力による発進時に駆動輪３４のスリップ状態を生じると、回転電機２の出力が変化して駆動輪３４の回転が急に高まることがあるが、こうしたスリップを抑えて発進を行える。
【００６３】
図４は本発明の別の実施の形態を示す。
【００６４】
これは、板バネ方式の後輪２軸（後前軸６０、後後軸６１）車の後後軸（駆動軸）６１と車体６２との間にエアサスペンション６３ａ、６３ｂを設け、車両の発進時に、後前軸６０、後後軸（駆動軸）６１の軸重に基づき、駆動輪（後輪６４）のスリップ状態を生じた場合あるいは登坂路の場合、駆動輪（後輪６４）に動的荷重を付与するように、ソレノイドバルブ（図示しない）を制御して、エアサスペンション６３ａ、６３ｂのベローズへエアリザーバタンクから所定圧のエアの供給を行う。
【００６５】
このようにすれば、板バネ方式の後輪２軸車に適用できる。
【図面の簡単な説明】
【図１】この発明の実施形態を表すシステム構成図である。
【図２】発進時の制御ブロック構成図である。
【図３】発進時の制御内容を説明するフローチャートである。
【図４】別の実施形態を表す部分概要図である。
【符号の説明】
１エンジン
２回転電機
３インバータ
４、５クラッチ
６変速機
１０車両コントロールユニット
１２蓄電装置
２０前車軸
２１ａ、２１ｂエアサスペンション
２２後車軸
２３ａ、２３ｂエアサスペンション
２４エアリザーバタンク
２５ａ、２５ｂ、２６ａ、２６ｂソレノイドバルブ
３０エアサスコントロールユニット
３１ａ、３１ｂ車高センサ
３２ａ、３２ｂ内圧センサ
３３前輪
３４後輪
３５、３６車輪速センサ
４０要求駆動トルク算出手段
４３駆動輪のスリップ状態判定手段
４４回転電機のトルク値補正出力手段
４５車高レベル判定手段
４６軸重判定手段
４７動的荷重選択手段
４８エアスプリングバルブ制御手段
５０エンジン制御手段[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a travel control device for a vehicle.
[0002]
[Prior art]
2. Description of the Related Art Conventionally, there is a vehicle suspension that uses an air suspension to improve ride comfort.
[0003]
Like a heavy-duty vehicle, one of the two rear wheel axles (for example, a rear-front axle) having a drive shaft and the other (for example, a rear-rear axle) having a driven shaft has a small load (axle load) on the drive shaft. If it is too long, it affects running, so that the air pressure of the air suspension of the drive shaft is relatively increased to increase the load sharing of the drive shaft.
[0004]
Therefore, when starting on a slippery road surface (low friction coefficient road surface) or an ascending road surface with a small amount of loading, etc., it is possible to start the vehicle without reducing the driving force and suppressing the slip (Patent) Literatures 1 to 3).
[0005]
[Patent Document 1]
JP-A-9-109645 [Patent Document 2]
JP-A-9-202123 [Patent Document 3]
JP-A-2001-213130
[0006]
[Problems to be solved by the invention]
Such axle load distribution can be performed for a rear-wheel two-axle vehicle, but cannot be applied to a vehicle with one front wheel and one rear wheel.
[0007]
Even in the case of a rear-wheel single-axle vehicle, when starting on a slippery road surface or climbing road surface, the driving force is reduced or slip occurs, and it is difficult to obtain a good start when starting on a slippery road surface or climbing road surface However, even if the air pressure of the air suspension of the drive shaft is relatively increased, the load sharing does not change.
[0008]
The present invention has been made in view of such a problem, and provides a travel control device for a vehicle that can apply a dynamic load to drive wheels and ensure good starting even with a rear-wheel single-axle vehicle. The purpose is to:
[0009]
[Means for Solving the Problems]
A first aspect of the present invention relates to a vehicle having valve means for supplying air of a predetermined pressure from an air tank to an air suspension and discharging air from the air suspension to an air suspension provided on a front axle and a rear axle. Vehicle height detection means for detecting the vehicle height level on the side and rear axle side, axle load detection means for detecting the axle weight of the front axle and rear axle, and slip detection means for detecting the slip state of the drive wheels, At the time of starting, based on the vehicle height level on the front axle side and the rear axle side and the axle weight of the front axle and the rear axle, when a slip state of the drive wheel occurs, the drive axle is to apply a dynamic load to the drive wheel. Start control means for controlling the valve means so as to extend or contract the air suspension, and for controlling the valve means to return to the original vehicle height level after the start.
[0010]
A second invention provides a vehicle having valve means for supplying air at a predetermined pressure from an air tank to an air suspension and discharging air from the air suspension to an air suspension provided on a front axle and a rear axle. A vehicle height detecting means for detecting a vehicle height level on the side and rear axle side; an axle load detecting means for detecting axle weight of the front axle and the rear axle; and an ascending road detecting means for detecting an ascending road. When the vehicle starts, the air suspension of the drive axle is extended or contracted to apply a dynamic load to the drive wheels based on the vehicle height level on the front axle side and the rear axle side and the axle weight of the front axle and the rear axle. Start control means for controlling the valve means so as to return to the original vehicle height level after starting.
[0011]
In a third aspect based on the first and second aspects, the start control means controls the valve means such that the air suspension other than the drive axle operates in the direction opposite to the air suspension of the drive axle.
[0012]
According to a fourth aspect, in the first to third aspects, the invention is directed to a vehicle operable by an engine and a rotating electric machine, wherein the control of the start control means is performed only at the time of starting only by the output of the rotating electric machine and when the output and rotation of the engine are changed. This is executed at the time of starting using the output of the electric machine together.
[0013]
【The invention's effect】
In the first invention, when a slip state of the drive wheel occurs at the time of starting, a dynamic load is applied to the drive wheel based on the vehicle height level on the front axle side and the rear axle side and the axle weight of the front axle and the rear axle. Is given, the contact pressure instantaneously increases, and the vehicle is started. Therefore, when starting on a slippery road surface, a decrease in driving force due to slippage can be suppressed, starting can be performed in accordance with the load amount, and good starting can be obtained.
[0014]
In the second invention, a dynamic load is applied to the drive wheels based on the vehicle height levels on the front axle side and the rear axle side and the axle weight of the front axle and the rear axle at the start of the uphill road, and the start is started. Done. Therefore, when starting on an uphill road, a decrease in driving force due to slippage can be suppressed, starting can be performed according to the load amount, and good starting can be obtained.
[0015]
In the third aspect, the dynamic operation of the drive wheels can be assisted.
[0016]
In the fourth aspect, in the hybrid vehicle, the vehicle can be started while suppressing a slip due to a change in the output of the rotating electric machine.
[0017]
BEST MODE FOR CARRYING OUT THE INVENTION
FIG. 1 shows a system configuration diagram of a hybrid vehicle having one front wheel axle (front axle: idler wheel) and one rear wheel axle (rear axle: drive wheel).
[0018]
In FIG. 1, reference numeral 1 denotes an engine, and 2 denotes a rotating electric machine (motor generator) having an inverter 3. The engine 1 and the rotating electric machine 2 are connected to a transmission 6 via clutches 4 and 5, respectively. Is transmitted to the drive wheels 34 of the rear axle 22.
[0019]
As the engine 1, a diesel engine (or a CNG engine using compressed natural gas as fuel) is employed. As the rotating electric machine 2, a permanent magnet synchronous motor (IPM synchronous motor) is used in terms of high efficiency and small size and light weight.
[0020]
The engine 1, the rotating electric machine 2, the clutches 4, 5, and the transmission 6 are controlled by the vehicle control unit 10 to depress an accelerator pedal (accelerator operation amount: accelerator opening), the rotation speed of the engine 1, and the rotation speed of the rotating electric machine 2. , The speed of the brake pedal 11, the SOC (state of change) of the power storage device 12, and the like.
[0021]
As the power storage device 12, an electric double layer capacitor is used which easily secures a required output density with respect to a battery allowable mass of the vehicle in order to regenerate braking energy in a short time and without waste.
[0022]
The vehicle control unit 10 sets the sharing ratio between the output of the rotating electric machine 2 and the output of the engine 1 in a predetermined control map using the SOC of the power storage device 12 as a parameter, and from the control map to the SOC of the power storage device 12. A corresponding output sharing ratio is determined, and the output of the rotating electric machine 2 and the output of the engine 1 are controlled based on the sharing ratio and the required driving force (accelerator operation amount).
[0023]
When the output sharing ratio of the rotating electric machine 2 is 1 (the output sharing ratio of the engine 1 = 0), an output corresponding to the accelerator operation amount is obtained from the rotating electric machine 2 in a state where the clutch 4 is disconnected (the clutch 5 is connected). The inverter 3 is controlled as described above. In the case where the output sharing ratio of the rotating electric machine 2 <1 (the output sharing ratio of the engine 1> 0), the shared output of the rotating electric machine 2 decreases as the SOC of the power storage device 12 decreases with the clutch 4 connected. The output of the engine 1 and the inverter 3 are controlled so that the shared output of the engine 1 increases accordingly. When the output sharing ratio of the engine 1 is 1 (the output sharing ratio of the rotary electric machine 2 = 0), the output of the engine 1 is controlled so that an output corresponding to the accelerator operation amount is obtained from the engine 1.
[0024]
In addition, at the time of deceleration for releasing the accelerator, the inverter 3 is controlled so as to generate electric power (regeneration electric power) of the rotating electric machine 2 in a state where the clutch 4 is disconnected, as long as charging of the power storage device 12 is possible. At the time of service braking, the rotating electric machine 2 performs power generation (regenerative power generation) in a state where the clutch 4 is disconnected as long as the power storage device 12 can be charged based on the amount of depression of the brake pedal 11 (required braking force). The inverter 3 is controlled as described above.
[0025]
When the vehicle is started, when the key switch is turned on (ST), the engine 1 is started, the clutch 4 is disengaged, and the engine 1 is stopped in an idling mode, and the start mode is set based on the SOC of the power storage device 12 and the like. Selected.
[0026]
In the case where the rotating electric machine 2 is started independently, in a state where the clutch 5 is connected (the transmission 6 is shifted to the starting gear), the rotating electric machine 2 is controlled so as to generate the required driving force in accordance with the depression of the accelerator pedal, The vehicle will start running.
[0027]
In the case of simultaneous start of the output of the engine 1 and the output of the rotary electric machine 2, with the clutch 5 connected (the transmission 6 is shifted to the starting stage), the clutch 4 is connected in accordance with the depression of the accelerator pedal. The engine 1 and the rotating electric machine 2 are controlled so as to generate their respective shared outputs, and the vehicle starts running.
[0028]
In the case where the engine 1 is started independently, in a state where the clutch 5 is disengaged (the transmission 6 shifts to the starting stage), the clutch 4 is connected and the engine 1 generates the required driving force in accordance with the depression of the accelerator pedal. And the vehicle will start running.
[0029]
On the other hand, air suspensions 21a and 21b are provided between the front axle 20 and the vehicle body of the vehicle, and air suspensions 23a and 23b are provided between the rear axle (drive shaft) 22 and the vehicle body.
[0030]
Solenoid valves 25a, 25b, 26a for supplying air at a predetermined pressure from the air reservoir tank 24 to the bellows and discharging air from the bellows to the bellows (air springs) of the air suspensions 21a, 21b, 23a, 23b, respectively. , 26b are provided.
[0031]
The solenoid valves 25a, 25b, 26a, 26b are detected by the air suspension control unit 30 to detect the vehicle height levels on the front axle 20 side and the rear axle (drive shaft) 22 side. , 21b, 23a, 23b, detection signals of internal pressure sensors 32a, 32b for detecting the internal pressure of the bellows (axle load of the front axle 20, rear axle 22), information of the vehicle control unit 10 (stop, start, run, etc.), brake Depression of the pedal 11, detection signals of wheel speed sensors 35 and 36 for detecting the rotation speed of each wheel (front wheel 33, rear wheel 34), detection signals of a tilt sensor 37 for detecting an uphill road, a vehicle height level operation switch (illustrated) No) is controlled based on the signal.
[0032]
The air suspension control unit 30 controls the solenoid valves 25a, 25b, 26a, 26b to set the vehicle height level on the front axle 20 side and the rear axle (drive shaft) 22 side to the level required by the vehicle height level operation switch.
[0033]
When the vehicle starts moving, if the driving wheels (rear wheels 34) are in a slip state or on an uphill road, the vehicle height levels on the front axle 20 side and the rear axle (drive shaft) 22 side, and the air suspensions 21a, 21b, 23a. , 23b based on the internal pressure of the bellows (the axle load of the front axle 20 and the rear axle 22), etc., to apply a dynamic load to the drive wheels (rear wheels 34) in the direction of extension or contraction of the air suspensions 23a, 23b. The solenoid valves 26a and 26b are controlled.
[0034]
FIG. 2 shows a block configuration of the control function at the time of starting (with respect to the slip of the drive wheels), and includes a required drive torque calculating unit 40, a unit 41 for calculating the rotational acceleration of the rotary electric machine 2, Means 42 for calculating the inertia torque of the drive shaft, means 43 for determining the slip state of the drive wheels, means 44 for correcting and outputting the torque value of the rotary electric machine 2, the front axle 20 side, the rear axle (drive shaft) 22 side Means for determining the vehicle height level, means for determining the axle load (distribution) of the front axle 20 and rear axle 22 from the internal pressure of the bellows of the air suspensions 21a, 21b, 23a and 23b, means for selecting the dynamic load 47 are provided.
[0035]
The required torque calculation means 40 calculates a required drive torque from the accelerator opening and the vehicle speed. The required driving torque of rotating electric machine 2 is set by an output sharing ratio based on the SOC of power storage device 12.
[0036]
The drive wheel slip determination means 43 determines the slip state of the drive wheel 34 based on the rotation speed of each wheel (the front wheel 33 and the rear wheel 34).
[0037]
At the time of starting, the rotating electrical machine torque value correction output means 44 outputs a torque command value to the inverter 3 so that the rotating electrical machine 2 generates a required driving torque of an output sharing ratio.
[0038]
At the time of starting, when the slip state of the drive wheel 34 is detected, the dynamic load selection means 47 determines the vehicle height level (the value before starting) on the front axle 20 side and the rear axle (drive shaft) 22 side, and the front axle. 20, air suspension valves (solenoid valves) 25a, 25b, 26a, and 26b are controlled to apply a dynamic load to the drive wheels (rear wheels 34) based on the axle load of the rear axle 22 (the value before starting). Then, a command is sent to the air spring valve control means 48.
[0039]
In this case, when the vehicle height level on the front axle 20 side and the rear axle (drive shaft) 22 side is equal to or lower than a predetermined level, air of a predetermined pressure is supplied from the air reservoir tank 24 to the bellows of the air suspensions 23a and 23b of the rear axle 22. A command is sent to the air spring valve control means 48 to supply it instantaneously. At the same time, the air of the bellows of the air suspensions 21a and 21b of the front axle 20 is instantaneously discharged.
[0040]
If the axle weight of the front axle 20 and the rear axle 22 is equal to or less than a predetermined value, and the vehicle height level of the front axle 20 and the rear axle (drive shaft) 22 exceeds a predetermined level, the air of the rear axle 22 A command is issued to the air spring valve control means 48 so that the bellows of the suspensions 23a and 23b are instantaneously discharged.
[0041]
When the slip state of the driving wheel 34 is no longer detected, the air spring valve control means 48 is instructed to return the vehicle height level on the front axle 20 side and the rear axle (drive shaft) 22 side to the original vehicle height level.
[0042]
The engine control means 50 controls the output of the engine 1 based on the output sharing ratio of the engine 1. In addition, when a slip state of the drive wheel (rear wheel 32) occurs during traveling, the output of the engine 1 is controlled to be reduced based on a correction command of the engine output correction means 51.
[0043]
The transmission control means 52 shifts the transmission 6 based on a command from the gear shift control means 53. The gear shift control means 53 prohibits gear shifting when a slip state of the drive wheel (rear wheel 32) occurs during traveling.
[0044]
FIG. 3 shows a flowchart of start control of the air suspension control unit 30.
[0045]
In S1, a start condition signal of the system of the hybrid vehicle is read.
[0046]
In S2, it is determined whether a start condition is satisfied.
[0047]
In S3, when the start condition is satisfied, the axle weight of the front axle 20 and the rear axle 22 is calculated from the internal pressure of the bellows of the air suspensions 21a, 21b, 23a, 23b.
[0048]
In S4, it is checked whether the vehicle is in a starting state. In the case where the rotating electric machine 2 is started independently, the state where the clutch 5 is connected (the transmission 6 is shifted to the starting stage) and the accelerator pedal is depressed, or the output of the engine 1 and the output of the rotating electric machine 2 are used together In the case of starting, in a state where the clutch 5 is connected (the transmission 6 is shifted to the starting stage), the accelerator pedal is depressed and the clutch 4 is connected (including a half clutch), or the engine 1 is started alone. In the case of (1), it is checked whether the accelerator pedal is depressed and the clutch 4 is connected (including the half-clutch) in a state where the clutch 5 is disengaged (the transmission 6 is shifted to the starting gear).
[0049]
In S5, it is determined whether or not the drive wheel 34 has slipped.
[0050]
If the drive wheel 34 slips, the vehicle height levels on the front axle 20 side and the rear axle (drive shaft) 22 side are checked in S6.
[0051]
In S7, when the vehicle height level on the front axle 20 side and the rear axle (drive shaft) 22 side is equal to or lower than a predetermined level, air of a predetermined pressure is supplied from the air reservoir tank 24 to the bellows of the air suspensions 23a and 23b of the rear axle 22. The solenoid valves 26a and 26b are controlled so as to supply the pressure instantaneously. At the same time, the solenoid valves 25a and 25b are controlled such that the bellows of the air suspensions 21a and 21b of the front axle 20 are instantaneously discharged.
[0052]
If the axle weight of the front axle 20 and the rear axle 22 is equal to or less than a predetermined value, and the vehicle height level of the front axle 20 and the rear axle (drive shaft) 22 exceeds a predetermined level, the air of the rear axle 22 The solenoid valves 26a and 26b are controlled so that the bellows of the suspensions 23a and 23b are instantaneously discharged.
[0053]
In S8, when the slip of the drive wheel 34 disappears, in S9, the solenoid valves 25a, 25b, 26a are set so that the vehicle height level on the front axle 20 side and the rear axle (drive shaft) 22 side is returned to the original vehicle height level. , 26b.
[0054]
On the other hand, in S4, it is checked whether the vehicle is starting on an uphill road. If the vehicle is starting on an uphill road, the processes after S6 are performed irrespective of the slip of the drive wheel 34.
[0055]
With this configuration, when the driving wheel 34 slips at the time of starting, the vehicle height level on the front axle 20 side and the rear axle (drive shaft) 22 side and the axle weight of the front axle 20 and the rear axle 22 are reduced. Based on this, the air suspensions 23a and 23b of the rear axle 22 are instantaneously extended or retracted.
[0056]
That is, a dynamic load is applied to the drive wheel (rear wheel 34), whereby the ground pressure is instantaneously increased, and the vehicle is started by the driving force transmitted via the transmission 6.
[0057]
In this case, when the vehicle height level on the front axle 20 side and the rear axle (drive shaft) 22 side is equal to or lower than a predetermined level, the air suspensions 23a and 23b of the rear axle 22 are supplied with air to the bellows. By the instantaneous extension, the drive wheel (rear wheel 34) is pressed and moved to the road surface. At the same time, the bellows of the air suspensions 21a and 21b of the front axle 20 discharge air to assist the pressing of the drive wheels (rear wheels 34).
[0058]
If the axle weight of the front axle 20 and the rear axle 22 is equal to or less than a predetermined value, and the vehicle height level of the front axle 20 and the rear axle (drive shaft) 22 exceeds a predetermined level, the air of the rear axle 22 The drive wheels (rear wheels 34) are pressed against the road surface by a reaction to the contraction of the air suspensions 23a, 23b due to the exhaust of the bellows of the suspensions 23a, 23b.
[0059]
On the other hand, in the case of starting on an uphill road, the driving wheels are determined based on the vehicle height levels of the front axle 20 and the rear axle (drive axle) 22 and the axle weight of the front axle 20 and the rear axle 22 as described above. A dynamic load is applied to the (rear wheel 34), and the vehicle is started by the driving force transmitted via the transmission 6.
[0060]
Therefore, when starting on a slippery road surface or on an uphill road, it is possible to perform a start that matches the loading amount by suppressing a decrease in driving force due to slippage, and does not require advanced driving techniques for road surface conditions and loading conditions, and is good. You can get a start.
[0061]
The control of the air suspensions 21a, 21b, 23a, 23b at the time of starting may be performed particularly when the rotating electric machine 2 is started alone and when the output of the engine 1 and the output of the rotating electric machine 2 are started together.
[0062]
In a hybrid vehicle, if a slip state of the drive wheels 34 occurs at the time of starting due to the output of the rotary electric machine 2, the output of the rotary electric machine 2 may change and the rotation of the drive wheels 34 may suddenly increase. You can start.
[0063]
FIG. 4 shows another embodiment of the present invention.
[0064]
In this configuration, air suspensions 63a and 63b are provided between a rear rear shaft (drive shaft) 61 of a vehicle and two rear wheels (a rear front shaft 60 and a rear rear shaft 61) of a leaf spring type and a vehicle body 62 to start the vehicle. Sometimes, based on the axle weight of the rear front shaft 60 and the rear rear shaft (drive shaft) 61, when the slip condition of the drive wheel (rear wheel 64) occurs or on an uphill road, the drive wheel (rear wheel 64) moves. By controlling a solenoid valve (not shown) so as to apply an appropriate load, air at a predetermined pressure is supplied from the air reservoir tank to the bellows of the air suspensions 63a and 63b.
[0065]
With this configuration, the present invention can be applied to a leaf spring type rear wheel two-axle wheel.
[Brief description of the drawings]
FIG. 1 is a system configuration diagram showing an embodiment of the present invention.
FIG. 2 is a control block diagram at the time of starting.
FIG. 3 is a flowchart illustrating control contents at the time of starting.
FIG. 4 is a partial schematic diagram illustrating another embodiment.
[Explanation of symbols]
Reference Signs List 1 engine 2 rotating electric machine 3 inverter 4, 5 clutch 6 transmission 10 vehicle control unit 12 power storage device 20 front axles 21a, 21b air suspension 22 rear axles 23a, 23b air suspension 24 air reservoir tanks 25a, 25b, 26a, 26b solenoid valves Reference Signs List 30 Air suspension control units 31a, 31b Vehicle height sensors 32a, 32b Internal pressure sensors 33 Front wheels 34 Rear wheels 35, 36 Wheel speed sensors 40 Required drive torque calculation means 43 Drive wheel slip state determination means 44 Rotary electric machine torque value correction output means 45 Vehicle height level determination means 46 Axle load determination means 47 Dynamic load selection means 48 Air spring valve control means 50 Engine control means

Claims

A vehicle provided with valve means for supplying air at a predetermined pressure from the air tank to the air suspension and discharging air from the air suspension, with respect to the air suspension provided on the front axle and the rear axle,
Vehicle height detecting means for detecting a vehicle height level on the front axle side and the rear axle side;
Axle load detection means for detecting the axle load of the front axle and the rear axle,
A slip detecting means for detecting a slip state of the drive wheel,
At the time of starting, based on the vehicle height level on the front axle side and the rear axle side and the axle weight of the front axle and the rear axle, when a slip state of the drive wheel occurs, the drive axle is to apply a dynamic load to the drive wheel. Vehicle starting control means for controlling the valve means to extend or contract the air suspension of the vehicle and controlling the valve means to return to the original vehicle height level after starting. apparatus.

A vehicle provided with valve means for supplying air at a predetermined pressure from the air tank to the air suspension and discharging air from the air suspension, with respect to the air suspension provided on the front axle and the rear axle,
Vehicle height detecting means for detecting a vehicle height level on the front axle side and the rear axle side;
Axle load detection means for detecting the axle load of the front axle and the rear axle,
Uphill detecting means for detecting an uphill,
At the start of an uphill road, the air suspension of the drive axle is extended or extended to apply a dynamic load to the drive wheels based on the vehicle height level on the front axle side and the rear axle side and the axle weight of the front axle and the rear axle. A travel control device for a vehicle, comprising: start control means for controlling the valve means so as to contract, and controlling the valve means so as to return to the original vehicle height level after the start.

3. The travel control device according to claim 1, wherein the start control unit controls the valve unit so that an air suspension other than the drive axle operates in a direction opposite to the air suspension of the drive axle.

In a vehicle that can run with the engine and rotating electric machine,
The control according to any one of claims 1 to 3, wherein the control of the start control means is performed at the time of start using only the output of the rotating electric machine and at the time of starting using both the output of the engine and the output of the rotating electric machine. The travel control device for a vehicle according to claim 1.