Ever-Power new planetary reducers hire a floating sun equipment rather than a set position one.
The saying ”There’s nothing new under the sun’ certainly pertains to planetary reducers. And, while floating sunlight gears have been around quite a while, some engineers might not end up being aware of the huge benefits this unusual gear design can offer.
Traditionally, planetary reducers possess used a fixed sun gear, where in fact the centre gear is attached to or machined into the shaft. When this set sun equipment revolves, it turns the planet gears to create movement and/or power. Ever-Power new planetary reducers, however, are having a floating sun gear rather than a fixed position sun gear.
Why a floating sunlight gear? ‘In the planetary idea, the sun may be the driver, or pinion, in the gear set,’Ever-Power design engineer Scott Hulstein said. ‘Because sunlight gear is in sun planet gear constant connection with the planets, it’s important that it is properly centred among the three planets in order to provide equal load posting among itself and all three planets.’
Due to normal manufacturing tolerances nevertheless, a sun gear which is securely set on a shaft will intermittently have more load on one planet gear than on another gear Hulstein explained. ‘By permitting the sun equipment to float, it centres itself among the three planets and produces constant, equal load sharing.’
Equal load sharing is just one of the advantages of this design. The floating sunlight gear provides ‘true involute action,’ according to Hulstein. True involute action occurs when the rolling movement between your mating gears is really as complete as possible. The benefit of this complete meshing of gears is longer reducer life, since less internal equipment slippage means fewer damaged gear teeth.
That also means lower noise levels. When sunlight gear is permitted to completely roll into the planet gears, there’s less ‘rattling’ as one’s teeth mesh. In effect, the Ever-Power product provides ‘designed out’ the apparatus mesh noise by allowing the sun equipment to float into place.
So why use a fixed sun gear at every? ‘Fixed sun gears are often used in true servo applications,’ Greg Pennings, Ever-Power Customer Advocate, explained. ‘A fixed sun gear is essential when specific positioning and low backlash are an integral part of the program.’ Ever-Power engineers, nevertheless, were less concerned with low backlash and more interested with higher torque and/or lower sound applications.
Our planetary reducers with floating sun gears were made to compete with parallel shaft reducers, where backlash was less critical,’ Pennings said.
By using the floating sun gear concept, the Ever-Power planetary reducers are able to exceed the torque rankings of similar sized and larger sized parallel shaft reducers, and yet maintain a lesser noise levels.
Sun, Ring and Planet
The most basic type of planetary gearset is demonstrated in the figures above. The figure at still left shows a three-dimensional look at as the figure at right provides a cross-section. In this geartrain, inputs and result can be extracted from the carrier, band and sun gears, and just the planet experiences epicyclic motion. That is the the majority of common kind of planetary gearset (apart from the differential) and it finds application in swiftness reducers and automatic transmissions. If you take apart a cordless drill, you’ll probably find this type of planetary gearset right behind the drill chuck.
Two Suns – Two Planets gearset
Cross-sectional view
Two Suns, Two Planets
The gearset proven above has two sun gears, and both planet gears (the yellow gears) rotate as a single unit. Sunlight gears (green and brown) can rotate independently of one another. The inputs and output can be selected from either sun equipment and/or the carrier. Very high speed reductions may be accomplished with this unit, nonetheless it can suffer from low efficiency if not designed correctly.
Reddish colored sun input – purple sun fixed
Purple sun input – reddish sun fixed
The animations above show the ‘two suns – two planets’ gearset with one sun as input and the other sunlight fixed. Remember that the carrier rotates clockwise in the animation at remaining and counterclockwise in the animation at right – even though the sun rotates counterclockwise in both situations.
The Differential
The gearset shown above is different from the preceding gearsets in that it is composed of miter gears rather than spur (or helical) gears. The ‘sun’ gears are those that do not go through the epicyclic motion experienced by the planet. And the differential can be used to gauge the difference in acceleration between two shafts for the purpose of synchronization. In addition, the differential is frequently used in auto drive trains to get over the difference in wheel speed when a car goes around a corner.