WORM WHEEL AND MANUFACTURING METHOD THEREOF

• Main Authors: YAMAUCHI MAI, WAKUKAWA YUJI, WADA YOSHINORI
• Format: Patent
• Language: English
• Published: 10.05.2012
• Subjects: AFTER-TREATMENT OF THE SHAPED PRODUCTS, e.g. REPAIRING; 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; SHAPING OF MATERIAL IN A PLASTIC STATE, NOT OTHERWISE PROVIDEDFOR; SHAPING OR JOINING OF PLASTICS; THERMAL INSULATION IN GENERAL; TRAILERS; TRANSPORTING; WEAPONS; WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE, IN GENERAL

PROBLEM TO BE SOLVED: To provide a worm wheel including a resin member and having excellent dimensional stability, which prevents steering torque and rattling noise from being increased when included in a reducer for an electric power steering device.SOLUTION: A worm wheel 20 includes a resin composition containing resin and a reinforcement fiber formed in a perimeter of an annual cored bar 23, is equipped with a tooth 21 in the perimeter, and has an annual resin member 22 formed by radially orienting the reinforced fiber from a central axis S radially outward. The manufacturing method includes: combining a mold for insert molding equipped with a supply path for supplying the resin composition to a holding part of the annual cored bar 23, with the cored bar equipped with a flow path communicating with the supply path to guide the resin composition to a peripheral face; and injecting the resin through the supply path and the flow path, into the mould cavity corresponding to the shape of the annual resin member 22.