I think that something like that would be custom made to suit the application. A spring steel rod properly tempered, etc. If you have any heat treatment shops around you they may be able to make some suggestions. The spring shaft might have to be quite long to get 270 degrees of movement out of the spring. The bad thing about springs is that eventually they may break possibly causing a safety issue. The other option might be some type of compressed air powered rotary actuator. Connected to a compressed air reservoir could act as a rotary spring.
Dave On 2/23/2015 3:54 AM, Viesturs Lācis wrote: > Hello! > > I would appreciate, if someone could share a source for torsion > springs, moment needed is 70 Nm, when there is 90 degrees still left > to reach max angle (for 270 degree max angle that would be ~105 Nm max > moment). > I ordered Lesjofors springs, received them today and discovered that > in the catalogue they have Nmm instead of Nm, so my springs are 1000x > too weak. I still have to figure out, how could I make such a foolish > mistake... > The space available for each spring is pretty big. I was thinking > about torsion springs from garage doors, but they do not seem to have > such a great moment, they have very big max angle, which I do not > need. Actually several springs can be used for each cover. I need them > to hold 20+ kg covers (there are 10 of them), max movement range from > closed to open is ~90 degrees. The cover might be horizontal, when in > open position and the spring(s) have to hold it. > It is just that max moment for strongest Lesjofors spring is 25 Nm and > using 6 of them seems like too much at the moment. > Normally people use gas springs to hold such covers, but I do not have > a space to introduce some kind of mount for the other end of such a > spring - it would interfere with material to be loaded in the machine. > So if there is any useful advice, I will be happy to read it :) > > Viesturs > > ------------------------------------------------------------------------------ > Download BIRT iHub F-Type - The Free Enterprise-Grade BIRT Server > from Actuate! Instantly Supercharge Your Business Reports and Dashboards > with Interactivity, Sharing, Native Excel Exports, App Integration & more > Get technology previously reserved for billion-dollar corporations, FREE > http://pubads.g.doubleclick.net/gampad/clk?id=190641631&iu=/4140/ostg.clktrk > _______________________________________________ > Emc-users mailing list > Emc-users@lists.sourceforge.net > https://lists.sourceforge.net/lists/listinfo/emc-users --- This email has been checked for viruses by Avast antivirus software. http://www.avast.com ------------------------------------------------------------------------------ Download BIRT iHub F-Type - The Free Enterprise-Grade BIRT Server from Actuate! Instantly Supercharge Your Business Reports and Dashboards with Interactivity, Sharing, Native Excel Exports, App Integration & more Get technology previously reserved for billion-dollar corporations, FREE http://pubads.g.doubleclick.net/gampad/clk?id=190641631&iu=/4140/ostg.clktrk _______________________________________________ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
