SUSPENSION SPRING DEVICE AND SUSPENSION COIL SPRING

• Main Authors: TANGE, Akira, OKADA, Hideki
• Format: Patent
• Language: English; Hungarian
• Published: 28.05.2019
• Subjects: BLASTING; CHEMISTRY; ENGINEERING ELEMENTS AND UNITS; GENERAL DEVICES FOR HEAT TREATMENT OF FERROUS OR NON-FERROUSMETALS OR ALLOYS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVEFUNCTIONING OF MACHINES OR INSTALLATIONS; HEATING; LIGHTING; MAKING METAL MALLEABLE BY DECARBURISATION, TEMPERING OR OTHERTREATMENTS; MEANS FOR DAMPING VIBRATION; MECHANICAL ENGINEERING; METALLURGY; METALLURGY OF IRON; MODIFYING THE PHYSICAL STRUCTURE OF FERROUS METALS; PERFORMING OPERATIONS; SHOCK-ABSORBERS; SPRINGS; THERMAL INSULATION IN GENERAL; TRANSPORTING; VEHICLE SUSPENSION ARRANGEMENTS; VEHICLES IN GENERAL; WEAPONS

A compressive residual stress portion (50) having a compressive residual stress from a surface of a wire (40) to a first depth (D1) is formed between end turn portions (12a, 12b) of a coil spring (12). The end turn portion (12a) includes a first portion (12a 1 ), a second portion (12a 2 ), and a third portion (12a 3 ). The first portion (12a 1 ) is always in contact with a spring seat irrespective of a load applied to the coil spring (12). The second portion (12a 2 ) contacts the spring seat when the load applied to the coil spring (12) is large, and is separated from the spring seat when the load is small. The third portion (12a 3 ) is always separated from the spring seat irrespective of the magnitude of the load. In the end turn portion (12a), in a region including the second portion (12a 2 ), a deep residual stress portion (51) is formed by ultrasonic shot peening. The deep residual stress portion (51) has a compressive residual stress from a surface of the wire (40) to a second depth (D2) deeper than the first depth (D1).