Patent ID: 6129647
Filing Date: 2000-10-10
Classification: F16H

Abstract:
A planacentric gear box having a gear ring with internal teeth and a gear wheel with external teeth, the difference of teeth numbers between gear ring and gear wheel being two to four, having a low speed hub with a circular rib whose periphery is connected to the gear ring with internal teeth, the gear wheel with external teeth orbiting inside the gear ring with internal teeth by the means of eccentrics, the eccentric shafts being synchronously driven by prime reducers having, in a well known manner, cylindrical gears, bevel gears or worm gears, those prime reducers being driven by one common input shaft and one motor, the improvement being that said planacentric gear box has the gear wheel with external teeth connected to a torque arm which passes beside the gear ring with internal teeth, this torque arm having, diametrically opposed, two protuberances receiving each the outer ring of the eccentric bearings which are generating the orbitation of the torque arm and consequently of the gear wheel with external teeth, the median planes of gear wheel and eccentric bearings being close one to the other, the eccentric bearings, located outside the gear ring with internal teeth, being journaled on eccentric shafts whose bearings are located in the side walls of the gear box housing.