Fusion gear reducer

A fusion gear reducer comprising:

• a housing;
• a first-stage gear reduction unit disposed in the housing, the first-stage gear reduction unit being an epicyclic gear train including a planet gears support, a sun gear as an input, a plurality of planet gears equally spaced around the sun gear and meshed therewith, and a ring gear disposed around the planet gears and meshed therewith;
• and
• a second-stage gear reduction unit disposed in the housing, the second-stage gear reduction unit being a harmonic drive including a plurality of equally spaced rollers arranged as a circle, a plurality of roller grooves, a plurality of wells formed on an inner surface of the housing, and a cam surface formed on an outer surface of the ring gear wherein the roller grooves are disposed between the cam surface and the wells, and the rollers are rotatably disposed in the roller grooves and confined by the cam surface, the wells, and the roller grooves;
• wherein the ring gear is an output of the first-stage gear reduction unit and an input for driving the second-stage gear reduction unit;
• wherein the rollers rotate the roller grooves;
• wherein the roller grooves are formed on an outer surface of the planet gears support;
• and
• wherein the planet gears support is an output of the second-stage gear reduction unit.