Posted by Jamie Stockton | Posted on 18.09.18
Planetary gearboxes are ideally suited to slow speed applications. This is due to the vast range of ratio combinations available through the addition of multiple gear stages, which in turn allows high amounts of torque to be transmitted. Certain applications, such as a conveyor with minimal load, may require the slow speed but only need a relatively low amount of torque to drive it. In some cases, however, the motor power needed is so low that it simply is not available to purchase.
A customer contacted us recently to ask for help in dealing with this exact scenario and we were only too happy to delve into our bag of expertise.
In the case of this application, we only needed 7 watts of power going into our gearbox to achieve the required output torque. There are a few issues with this. Firstly, it would not be feasible to source such a low powered motor. Secondly, the power going into the gearbox would be so low that it would struggle to drive through the gear sets. The natural solution would be to increase motor power, but in doing so we are increasing the amount of torque at the gearbox output shaft and exceeding the mechanical limits of a gearbox.
To keep gearbox size and cost to a minimum we created a solution whereby a pre-stage gear unit with an integral torque limiter would sit between the motor and planetary gearbox. This meant that we could install a motor power high enough to drive through the high gear ratio whilst using the torque limiter to pre-set the perfect slipping point so as not to exceed the mechanical limits of the planetary gearbox.
The benefits of this solution speak for themselves. Reduced gearbox size, reduced costs and increased lifespan.
Contact STM UK to see what we can do for you.