Planet gears share the load using swing links

Aug. 3, 2000
New gearheads are offered in four frame sizes (40, 60, 90, and 115 mm) with three front face mounting options (NEMA, metric, and C-Face).
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The goal for engineers at Thomson Micron LLC, Ronkonkoma, N.Y., was to develop a line of low-cost planetary gearheads that perform equal to or better than current market offerings, while being compact, easy to mount, modular, and easy to produce. The result is the Equalizer. Key to this new line of planetary gearheads is a system in which planet gears dynamically adjust their radial position between the mating sun gear and internal gears through a pivoting link. With this "Swing-Link" technology, loads are evenly distributed through all three planet gears.

Here's how it works. Each of the three planetary gears has a swing link that essentially lets it pivot. This lets the gears mesh smoothly and reduces noise, vibration, and cyclic loading of the gear teeth.

When compared to a fixed-planet configuration, the gearheads are said to show a 3 to 11% efficiency increase as well as a 20% decrease in torque ripple -- the input-torque variation that results when driving gearheads at low speeds. Moreover, tests show that the gearheads run quieter and last longer than fixed-planet gears. The Equalizer gearhead line, claim company officials, also offers high torque-to-envelope ratios when compared to parallel-shaft designs because the planets equally share torque. Additionally, the gearbox mounts in less then 5 min using the company's motor-mounting system. Circle 401

With these front face options, the new gearheads are said to be an easy drop-in replacement for parallel-shaft spur gearheads and other similar reducers.

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