ELECTRIC POWER STEERING DEVICE AND RACK SHAFT FOR ELECTRIC POWER STEERING DEVICE

• Main Authors: IIJIMA KIYOTAKA, UENO SEIJI
• Format: Patent
• Language: English; Japanese
• Published: 07.08.2023
• Subjects: BLASTING; ENGINEERING ELEMENTS AND UNITS; GEARING; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVEFUNCTIONING OF MACHINES OR INSTALLATIONS; HEATING; LAND VEHICLES FOR TRAVELLING OTHERWISE THAN ON RAILS; LIGHTING; MECHANICAL ENGINEERING; MOTOR VEHICLES; PERFORMING OPERATIONS; THERMAL INSULATION IN GENERAL; TRAILERS; TRANSPORTING; WEAPONS

To facilitate ensuring a contact area between a tooth flank of a rack tooth and a tooth flank of a pinion tooth in each on a steering side and an assist side in spite of a manufacturing error of a rack shaft.SOLUTION: Of a tooth flank of a tooth of a steering-side rack 28, a tooth flank of a tooth in a range in a tooth width direction range overlapping with the steering-side rack 28 of a steering-side pinion 25, a tooth flank of a tooth of an assist-side rack 29, and a tooth flank of a tooth in a tooth width direction range overlapping with the assist-side rack 29 of an assist-side pinion 41, in at least a part in a tooth muscle direction of the tooth flank of the tooth of the steering-side rack 28 and/or a part of the tooth flank of a tooth in a tooth width direction range overlapping with the steering-side rack 28 of the steering-side pinion 25, crowning processing is executed.SELECTED DRAWING: Figure 1 【課題】ラック軸の製造誤差などにかかわらず、操舵側およびアシスト側のそれぞれにおいて、ラックの歯の歯面とピニオンの歯の歯面との間の接触面積を確保しやすくする。【解決手段】操舵側ラック２８の歯の歯面と、操舵側ピニオン２５のうち操舵側ラック２８と重なる歯幅方向範囲における歯の歯面と、アシスト側ラック２９の歯の歯面と、アシスト側ピニオン４１のうちアシスト側ラック２９と重なる歯幅方向範囲における歯の歯面とのうち、操舵側ラック２８の歯の歯面の歯筋方向の少なくとも一部、および／または、操舵側ピニオン２５のうち操舵側ラック２８と重なる歯幅方向範囲における歯の歯面の一部にクラウニング加工が施されている。【選択図】図１