What is a caged planet carrier?

It's very important to understand in which application it is safe to recommend a gearbox with a basic shaft, and in which application the caged planet carrier is compulsory to provide a long life span.

The planet carrier is a very precise part that supports the planet gears inside of a planetary gearbox.

This highly sensitive component can be of two kinds : it can be a cantilever planet carrier or a dual-support planet carrier (also called a "cage").

• In the case of a cantilever shaft, the planet gears are only held to the output shaft by means of one axle, which is press-fitted into the shaft. As a consequence, all the torque of the planet gear is transmitted to the output shaft from only one end of this axle. Under high load conditions the axle bends, which transfers the contact pressure from the center of the gear to the edge of the teeth.

• Using a caged planet carrier allows supporting the planet gears from both sides. As a consequence the contact pressure is distributed alongside the entire pitch line. This added stiffness increases the torque capacity by 40 to 50% and can prolonge the life of the product by many years. It makes the products more reliable under dynamic conditions. Supporting the gears from both sides also boosts stiffness, and makes our gearboxes very easy to tune if your application is dynamic.

Apart rom our Heliks and Spirit lines, all Reckon gearboxes include a robust, monobloc cage, even when face to face competition products only offer a cantilever shaft.