On Aug 5, 2014, at 3:26 PM, Roger Stockton via EV <[email protected]> wrote:
> Ben Goren wrote: > >> The AC-51s use 6207-2RS bearings; my main job is to research their side >> loading capacity. However, Bill says there're a number of side-loaded AC- >> 35s out there, and that he thinks I'm probably okay -- though, of course, >> I need to confirm that. If anybody can suggest a good way to put some >> numbers to that, I'd appreciate it. > > Not sure if it helps, but here is a specific example of a pair of HPEVs > AC-31s installed in a side-loaded arrangement: > > <http://evalbum.com/4283> Very interesting! That exact design won't work, as I'm keeping the V8 -- but the basic geometry is very similar to what I have in mind. Basically, I'll be driving pulleys directly on the driveshaft rather than an intermediate gear, and relying on smaller pulleys on the motors than those on the driveshaft to get the gear ratio. The exact pulleys will depend on the gearing I decide on for the V8.... > Regarding putting numbers on the acceptable side load, or conversely, on the > life of the bearing under a given load condition, this Timken calculator > might be useful: > > <http://www.timken.com/EN-US/Knowledge/engineers/Pages/BearingLife.aspx> > > Your 6207 crosses dimensionally to Timken's 207W, MM207K, and MMC207K ball > bearings; of these, the 207W seems to have higher rated life. On this page, > click 'Select Type' and select "BB" from the list, then enter "207W" into the > part number box and click 'Lookup'. After this you can enter radial and > axial loads and speed values and hit 'Calculate' to see the effect on fatigue > life. Thanks for that. I'm not sure I'm understanding the math right, but I *think* Harley belt drives are supposed to be tensioned to 10 lbf. I think I'm reasonably sure that I've got the order of magnitude right, at least. Using 10 lbf radial, 100 lbf axial (the motor's torque rating), and 5000 RPM, I get a rating of close to 2 million hours. Just for giggles, if I make it 100 lbf for both, it still has about a million hours rating. Any chance you can tell me if I've at least got the right order of magnitude? If so, I'm not going to worry. Even if it only has a 10,000 hour lifespan, that's still over half a million miles at freeway speeds. b& -------------- next part -------------- A non-text attachment was scrubbed... Name: signature.asc Type: application/pgp-signature Size: 801 bytes Desc: Message signed with OpenPGP using GPGMail URL: <http://lists.evdl.org/private.cgi/ev-evdl.org/attachments/20140805/15c63108/attachment.pgp> _______________________________________________ UNSUBSCRIBE: http://www.evdl.org/help/index.html#usub http://lists.evdl.org/listinfo.cgi/ev-evdl.org For EV drag racing discussion, please use NEDRA (http://groups.yahoo.com/group/NEDRA)
