Re: ATM Backlash control in worm gear sets

[andydtg@phoenix.net]

Del Stanton wrote:

>The large telescopes manufactured by Boller & Chiven (later a division of
>Perkin-Elmer),
> 12" to 60" inches in aperture had a counterweight system that kept the worm
>play
>"forced to one side", thus effectively eliminating backlash.

Another method was used by Ealing in medium size GEM's built in the late 60's,
they added a large spur gear co-axial to the worm gear, with a DC torque motor
keeping the worm gear pre-loaded. The amount and direction of the preloading
could be adjusted, up to about 10 ft-lbs.



Andy Saulietis / DTG Alt-Az-Fp Drive Systems
12617 Harriet Ln
Santa Fe, TX 77510 USA
409-925-8854 Voice/Fax