Injection molded resin gear, injection molded resin rotating body, and injection molded article

摘要

An injection molded resin gear 1 includes a rim 4 , a hub 3 and a web 5 which connects the rim 4 to the hub 3 . A plurality of ribs 7 for guiding a molten resin, which is injected from pin point gates 8 , to the hub 3 protrude from the outer periphery of the hub 3 on one side of the web 5 so as to correspond to the pin point gates 8 . The ribs 7 are formed so as to be recessed from the side face 10 of the hub 3 . In the connecting portions of the ribs 7 to the hub 3 , fillet portions 12 are formed for smoothly guiding the flow of the resin from the hub 3 toward the web 5 when the injection molded resin gear 1 is formed.