An epicyclic gear teach (also called planetary gear) includes two gears mounted so that the centre of 1 gear revolves around the centre of the other. A carrier links the centres of the two gears and rotates to carry one gear, called the planet gear or planet pinion, around the other, called sunlight gear or sun wheel. The earth and sunlight gears mesh to ensure that their pitch circles roll without slip. A spot on the pitch circle of the earth gear traces an Planetary Reducer Gearbox epicycloid curve. In this simplified case, sunlight equipment is set and the planetary equipment(s) roll around the sun gear.
An epicyclic gear train can be assembled therefore the planet equipment rolls on the inside of the pitch circle of a set, outer gear ring, or ring gear, sometimes called an annular equipment. In this case, the curve traced by a spot on the pitch circle of the earth is a hypocycloid.
The mixture of 
epicycle gear trains with a planet engaging both a sun gear and a ring gear is called a planetary gear train.[1][2] In cases like this, the ring equipment is generally fixed and sunlight gear is driven.
Epicyclic gears obtain name from their earliest software, that was the modelling of the motions of the planets in the heavens. Believing the planets, as everything in the heavens, to be perfect, they could just travel in ideal circles, but their motions as viewed from Earth cannot be reconciled with circular motion. At around 500 BC, the Greeks invented the thought of epicycles, of circles travelling on the circular orbits. With this theory Claudius Ptolemy in the Almagest in 148 AD could predict planetary orbital paths. The Antikythera System, circa 80 BC, had gearing which was able to approximate the moon’s elliptical route through the heavens, and even to correct for the nine-year precession of that route.[3] (The Greeks could have seen it not as elliptical, but instead as epicyclic motion.)
EP, a versatile and multi-use solution, is not simply another simple planetary gearbox. EP high-tech planetary reducer is definitely a true integrated concept, including some functions combined together to provide a complete sub-assembly to the most demanding machines.
EP is the ultimate high-tech servo-reducer, specially focused on designs requiring:
Superior output torsional stiffness
Ultra-huge output radial stiffness and Tilting moment
Patented output bearing design
A high-tech planetary gear train, based on REDEX’s differential know-how
ISO 9409-1 result drive flange for installation pinions, pulleys, couplings, etc.
High input speeds
Superior acceleration and excellent torque density
Minimum backlash (1 – 3 arc-minutes)
In-Line or proper angle arrangements
This versatile design makes it possible for design engineers to find exact solutions to the most demanding applications.
Parallel shaft Gearmotors
Helical Single-Stage
The S Series style may make this gearmotor particularly effective for fan, blower applications and pump. To meet the needs of customers in these sectors, the S Series is also available in the foot or flange versions and will be completed with an array of electric motors entirely manufactured by EP. Asynchronous motors both IEC and compact (B-BE-BX/M-ME-MX), servomotors (BMD) and reluctance motors (BSR) can be in conjunction with the S Series: with the breadth of its portfolio, EP provides clients with an outstanding balance of efficiency, cost effectiveness and dynamics.