Abstract: Provided is a method for manufacturing a gear wheel, the method including: preparing an insertion unit formed of a steel material having a hollow pipe shape; injection-molding an outer side unit including teeth on an outer circumference; and molding a connection unit having a wheel shape by injecting resin into at least three points between the insertion unit and the outer side unit so as to connect the insertion unit and the outer side unit after arranging the insertion unit on the inner center of the outer side unit. According to the method, removing of an unnecessarily injected portion may be omitted since the resin is injected between the insertion unit and the outer side unit while injection-molding the connection unit. Also, productivity is increased by decreasing a number of defective products generated due to cracks.

Abstract: Provided is a method for manufacturing a gear wheel, the method including: preparing an insertion unit formed of a steel material having a hollow pipe shape; injection-molding an outer side unit including teeth on an outer circumference; and molding a connection unit having a wheel shape by injecting resin into at least three points between the insertion unit and the outer side unit so as to connect the insertion unit and the outer side unit after arranging the insertion unit on the inner center of the outer side unit. According to the method, removing of an unnecessarily injected portion may be omitted since the resin is injected between the insertion unit and the outer side unit while injection-molding the connection unit. Also, productivity is increased by decreasing a number of defective products generated due to cracks.