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  1. What is an anti-backdrive gear reducer?
  2. Can a gear reducer be used in reverse as a multiplier?
  3. When should the grease in a gear reducer be changed?
  4. Does HPC produce custom-made gearboxes?


1. What is an anti-backdrive gear reducer?

gear reducerWhat is meant by anti-backdrive? To put it simply, if you apply a torque to the output of an anti-backdrive gearbox and the input does not move, the gearbox can then be called anti-backdrive.


It is important not to confuse the notion of anti-backdrive with a gearbox that is designed to only rotate in one direction. The input of an anti-backdrive gearbox may be able to rotate in both directions and as a consequence so will the output. Very few gearboxes have anti-backdrive characteristics; typically these are worm and wheel gearboxes with a low lead angle.


To be more precise, gearboxes having a single start on the worm are anti-backdrive, those with three or more starts are reversible.

Where the worm has two starts, it is not the angle of the thread but the application that will determine whether the gearbox is anti-backdrive or not.


If your application requires the gearbox to block reverse rotation, do not use a gearbox where the worm has two starts. In summary, only worm and wheel gear reducers where the worm only has one start can be sure to be anti-backdrive.


2. Can a gear reducer be used in reverse as a multiplier?

gear reducerAs implied by their name, HPC gear reducers are designed to produce a lower speed on the output compared to the input.


However the majority of our gearboxes are reversible (the input will rotate if the output is turned) but they should not be used as multipliers as using them in this way can create internal stresses and cause irreparable damage. 


HPC's 13 month guarantee on gearboxes will not apply for any unit used in this way.


3. When should the grease in a gear reducer be changed?

 HPC gear reducers are greased for life and are thus maintenance free.


Whilst certain gearboxes do have a grease nipple this is only used to fill the gearbox during manufacture, it should not be used afterwards.


Under no circumstances should an HPC gearbox be opened up for maintenance without our prior agreement. Contact our technicians on +33(0)4 37 496 496.


4.Does HPC produce custom-made gearboxes?

Yes. Please e-mail or fax us your requirements. We are very flexible and are happy to quote for small, medium or large volumes.  Here are some examples of custom-made gearboxes.

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