PROBLEM TO BE SOLVED: To determine a drive force reduction speed in accordance with a sensitivity of a vehicular behavior in response to a change in a left-right wheel drive force differential, the speed in decreasing drive force of at least one wheel of left and right wheels to an allowable upper limit value at the time of abnormality occurrence.SOLUTION: When decreasing drive force of at least one of left and right wheels to an upper limit value, a control apparatus decreases a torque-decrease gradient Tg proportionately, as a vehicular speed increases (step S31), as lateral acceleration Gy increases (step S32), as a left-right wheel slip ratios λL, λR increase (step S33), and as a load shift amount to the front wheel increases (steps S34-S36), so that the smallest of the aforementioned cases is determined to be a torque-decrease gradient Tg. Therefore, as a sensitivity of vehicular behavior increases, the torque-decrease gradient Tg decreases proportionately, and a speed with which the drive force on at least one wheel is decreased to an upper limit value is lowered proportionately as the sensitivity of the vehicular behavior increases so as to prevent an adverse effect of an extraneous suppression of drive force decrease speed in a scene with a low sensitivity of vehicular behavior, while avoiding disturbance in the vehicular behavior in a scene with a high sensitivity of vehicular behavior.SELECTED DRAWING: Figure 3
【課題】左右輪の少なくとも一方車輪の駆動力を異常発生時許容上限値へ低下させる際の駆動力低下速度を、左右輪駆動力差の変化に対する車両の挙動感度に応じ決定する。【解決手段】左右輪の少なくとも一方の駆動力を上限値へ低下させる時のトルク減少勾配Tgを、車速VSPが速いほど小さくし(ステップS31)、横加速度Gyが大きいほど小さくし(ステップS32)、左右輪スリップ率λL,λRが高いほど小さくし(ステップS33)、前輪への荷重移動量が大きいほど小さくし(ステップS34〜ステップS36)、これら四者の最も小さいものをトルク減少勾配Tgと定める。よって車両の挙動感度が高いほどトルク減少勾配Tgが小さくなり、少なくとも一方車輪の駆動力を上限値へ低下させる時の速度を、車両の挙動感度が高いほど遅くして、車両挙動感度が高いシーンで車両挙動の乱れを回避しつつ、車両挙動感度が低いシーンで無用に駆動力低下速度の抑制が行われる弊害を回避する。【選択図】図3
LEFT-RIGHT WHEEL DRIVE FORCE DIFFERENTIAL CONTROL APPARATUS
左右輪駆動力差制御装置
2016-05-19
Patent
Electronic Resource
Japanese
IPC: | B60W CONJOINT CONTROL OF VEHICLE SUB-UNITS OF DIFFERENT TYPE OR DIFFERENT FUNCTION , Gemeinsame Steuerung oder Regelung von Fahrzeug-Unteraggregaten verschiedenen Typs oder verschiedener Funktion / B60K Anordnung oder Einbau von Antriebseinheiten oder von Kraft- bzw. Drehmomentübertragungen in Fahrzeugen , ARRANGEMENT OR MOUNTING OF PROPULSION UNITS OR OF TRANSMISSIONS IN VEHICLES / B60L PROPULSION OF ELECTRICALLY-PROPELLED VEHICLES , Antrieb von elektrisch angetriebenen Fahrzeugen |
Left-right wheel drive force distribution control apparatus for a vehicle
European Patent Office | 2015
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