Internal gear and manufacturing method thereof with die

• Main Author: Nagata, Eiri
• Format: Patent
• Language: English
• Published: 08.01.2019
• Subjects: BLASTING; ENGINEERING ELEMENTS AND UNITS; GEARING; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVEFUNCTIONING OF MACHINES OR INSTALLATIONS; HEATING; LIGHTING; MACHINE TOOLS; MAKING GEARS OR TOOTHED RACKS; MAKING PARTICULAR METAL OBJECTS BY ROLLING, e.g. SCREWS,WHEELS, RINGS, BARRELS, BALLS; MECHANICAL ENGINEERING; MECHANICAL METAL-WORKING WITHOUT ESSENTIALLY REMOVINGMATERIAL; METAL-WORKING NOT OTHERWISE PROVIDED FOR; PERFORMING OPERATIONS; PUNCHING METAL; THERMAL INSULATION IN GENERAL; TRANSPORTING; WEAPONS

An internal gear includes plural teeth each including an addendum area, a dedendum area, and an intermediate area including a protrusion and a recessed portion. The intermediate area includes a first border position provided at a position between the protrusion and the recessed portion, a second border position provided at a position between the intermediate area and the dedendum area, a third border position provided at a position between the intermediate area and the addendum area, a first average radius provided from the first border position to the second border position, and a second average radius provided from the first border position to the third border position. The first average radius is smaller than the second average radius. The addendum area includes a first curvature radius provided at a first center position in a tooth thickness direction, the first curvature radius being set at a maximum.