On Tue, 27 Jul 2021 at 00:13, Sam Sokolik <[email protected]> wrote: > > Is there a reduction? What is the rated rpm?
I have a cunning plan for a simple electronically-controlled 2-speed drive for this sort of application. The idea is to use both a one-way clutch/bearing and a vehicle air-conditioning clutch. Both are relatively cheap: https://simplybearings.co.uk/shop/p152523/CSK20PP-20mm-Sprag-Clutch-One-Way-Bearing-with-Internal-&-External-Keyways-20x47x14mm/product_info.html https://www.ebay.co.uk/itm/264754327786 The AC clutch includes bearings and a poly-V pulley. The idea is to have two separate pulley ratios. There are other possible arrangements, but one way is with the AC clutch mounted to the motor flange, and then a smaller pulley mounted outboard of that also on the motor shaft on the over-running clutch. When the clutch is engaged the drive is 1:1 (or similar) via the poly-vee with the sprag clutch overrunning. When the AC clutch is disengaged the smaller pulley on the motor takes up the drive. A drawback of this simple arrangement with one active clutch is that it only works in one direction. (with the AC clutch closed in the revere direction the sprag does not over-run, and with it open nothing drives at all) There are other possible arrangements of which is high-ratio and which is low, but I think that they all have the same problem. A manual lock-out for rigid-tapping might be an option. I actually have had very little reason to run my own lathe in reverse. Fitting two AC clutches might be an option, one on the motor and one on the headstock. Or both back-to-back on the motor shaft with an extra mounting face for the second coil. -- atp "A motorcycle is a bicycle with a pandemonium attachment and is designed for the especial use of mechanical geniuses, daredevils and lunatics." — George Fitch, Atlanta Constitution Newspaper, 1912 _______________________________________________ Emc-users mailing list [email protected] https://lists.sourceforge.net/lists/listinfo/emc-users
