MANUFACTURE OF AUTOMOBILE UNIFORM VELOCITY JOINT

• Main Author: HIBINO YOSHIHIRO
• Format: Patent
• Language: English
• Published: 14.04.1989
• Subjects: BLASTING; BRAKES; CHEMISTRY; CLUTCHES; COUPLINGS FOR TRANSMITTING ROTATION; 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; MECHANICAL ENGINEERING; METALLURGY; METALLURGY OF IRON; MODIFYING THE PHYSICAL STRUCTURE OF FERROUS METALS; THERMAL INSULATION IN GENERAL; WEAPONS

PURPOSE:To manufacture a uniform velocity joint improved in hardenability at the sliding surface by applying carburizing, hardening, and tempering treatments to an outer race and an inner race, assembling them while attaching a rolling element between them, and then providing rotation under loaded condition so as to form the contact surface into martensite. CONSTITUTION:An outer race and an inner race are subjected to carburizing, hardening, and tempering treatments, by which the amount of precipitation of residual austenite is regulated to 30-55% at a depth as far as 30-50mu from the surface and also to 15% at a depth of >=50mu, respectively. The above outer and inner races are assembled while attaching a rolling element between them, and then, 1,000-5,000 revolutions are provided under a load of 100-150kg/mm surface pressure at the contact surface to give a break-in rotation to the rolling element. Subsequently, 500-2,000 revolutions are provided under a load of 400-450kg/mm surface pressure, by which residual austenite at the contact surface is transformed to martensite by means of working-induced martensite transformation. By this method, the uniform velocity joint in which the contact surface of the rolling element is hardened can be obtained.