An Internal Gear could be described as the opposite of an external gear in that the teeth point towards planetary gearbox instead of away from the guts, and addendum and dedendum take invert positions. Internal Gears provide a small parallel shaft transmitting drive with large rate reduction. Used with a typical spur pinion the ratio is equivalent to that of two exterior gears, however the center distance is much smaller. In cases where it is necessary to possess two parallel shafts rotate in the same direction, the internal gear eliminates the use of an idler gear.

Internal Gears possess a number of advantages when properly used. One such advantage is reduced sliding actions. The corresponding working surfaces of the teeth of an internal equipment and pinion are more nearly of the same size than may be the case with an external gear and pinion having the same tooth ratio and tooth duration. Which means relative slippage of the teeth is less regarding the internal. This point presents one of the benefits of using Internal Gears. The sliding action of one tooth over another causes friction; and because friction results in tooth put on, a reduction in the amount of sliding action is usually desirable.

Internal Gear drives could be operated with the gear in a set position and the pinion rotating along the pitch line, or the gear may be absolve to rotate with the pinion rotating in a set position.

When mating pinions are too close in proportions to the gear, interference may result. For that reason, the difference in the teeth of the pinion to the gear should not be less than 15.

RUSH GEARS inc. provides standard Internal Gears in Metal, STAINLESS STEEL, CAST IRON, BRONZE, Aluminium, DELRIN and NON-METALLIC (PHENOLIC). We will gladly produce made to order Internal Gears to meet your needs.