Internal Ring Gear
Internal Ring Gear shaped which the teeth are aligned on the internal face of the ring, the matching gear is located on the internal area of the internal ring gear and with this method the area of the teeth contact surface is increased. This fact increase the life span of the gears by reducing loads from the gears, this type of gears are used in a planetary gears which made for high ration. When choosing a matching gear the size difference between the internal ring and the matching needs to be at least 15 teeth less than the internal ring gear (for the matching gear).
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