'Ball screw' type worm & worm wheel drive
'Ball screw' type worm & worm wheel drive
(OP)
Interesting video showing a 'ball screw' type worm & worm wheel drive.
I wonder what sort of loses there'd be and how smooth the engagement would be.
http://youtu.be/hvz9A0c_HeQ
I wonder what sort of loses there'd be and how smooth the engagement would be.
http://youtu.be/hvz9A0c_HeQ
Ron Volmershausen
Brunkerville Engineering
Newcastle Australia
http://www.aussieweb.com.au/email.aspx?id=1194181





RE: 'Ball screw' type worm & worm wheel drive
I can't help but think that I've seen it done before, and better, as in a double-cone double-enveloping worm.
I'd expect the efficiency to be similar to that of a ballscrew assembly, if the geometry is right.
Mike Halloran
Pembroke Pines, FL, USA
RE: 'Ball screw' type worm & worm wheel drive
It looks like the diameter of the cutter that he used for the gear's profile was too large, much larger than the worm's diameter anyway.
I'd imagine the generating tool for the gear's profile would look like something similar to a profile used for cutting roller chain sprockets.
He has other videos showing a double enveloping design.
Ron Volmershausen
Brunkerville Engineering
Newcastle Australia
http://www.aussieweb.com.au/email.aspx?id=1194181
RE: 'Ball screw' type worm & worm wheel drive
Recirculating ball screws work acceptably because the ball and race contacts produce very little skidding. The approach and recess motion of the race surfaces of the gear makes for a much more complex contact geometry than ball screw threads do.