Author Topic: How does this clutch work?  (Read 3563 times)

Offline Roger B

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Re: How does this clutch work?
« Reply #75 on: October 05, 2018, 08:21:21 PM »
Just catching up with this one. I have seen various versions of this design in old engine books. Looking foreword to seeing how it works  :ThumbsUp:  :ThumbsUp:  :wine1:
Best regards

Roger

Offline Brian Rupnow

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Re: How does this clutch work?
« Reply #76 on: October 05, 2018, 08:27:05 PM »
Hi Roger--this is a new one for me also, and I find it quite interesting.---Brian

Offline Brian Rupnow

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Re: How does this clutch work?
« Reply #77 on: October 08, 2018, 10:46:42 PM »
Spent today eating turkey and pumpkin pie--House was full of adult children and grandchildren. Good wife cooked her usual fantastic thanksgiving dinner.--and when I wasn't actively engaged in being grandpa I was thinking about clutches. Earlier in the week I had looked up and studied on a wrap-spring clutch, which I have never heard of before but now I know how they work. Also looked at a number of "over center" manual clutches and electromagnetic over-center clutches. I have built cone style clutches and expanding shoe clutches and dog clutches. They all seem to work, but they all (except for the dog clutch) seem to have too many parts to "miniaturize" down to a point where they work repeatably and consistently on an engine with a 3/8" crankshaft. I also looked at a proprietary friction clutch which is sold for go-carts and mini-bikes, but couldn't really tell how it operated. I hope to get the final part for my current clutch build back from case hardening this week to finish it up.---Brian

Offline Brian Rupnow

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Re: How does this clutch work?
« Reply #78 on: October 09, 2018, 10:35:45 PM »
Today I'm just dickin' around. No real work and my clutch part isn't back from case hardening yet. Of all the different clutches I've designed, the expanding shoe clutch seems to lend itself best to installing on a small engine. It is relatively small at 1 3/4" diameter, and it doesn't put any axial load into the crankshaft. I checked out all of my engines, and the one most suited to adding a clutch to was the flathead engine I had featured in the Home Shop Machinist magazine a few years ago.

Offline Brian Rupnow

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Re: How does this clutch work?
« Reply #79 on: October 15, 2018, 11:43:40 PM »
It seems that my case hardening friend has let me down. I will give him one more week and then I will get the part back and use it unhardened, or else build another from 01 and harden it myself.---Sorry about the delay.---Brian

Offline Brian Rupnow

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Re: How does this clutch work?
« Reply #80 on: October 19, 2018, 04:43:42 PM »
Okay--We're back in the saddle again on this project. I just went down to the machine shop that was going to have my tapered hub case hardened, and then didn't.--Moving on--I'm going out to my main garage right now and set this up with a motor to drive it, and see if and how well it works. A video and picture will be posted here shortly.---Brian

Offline Brian Rupnow

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Re: How does this clutch work?
« Reply #81 on: October 19, 2018, 06:29:40 PM »
And as I promised, here we have a still shot of the assembled clutch, and a nice video of it in operation---Brian

t=4s

Offline Brian Rupnow

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Re: How does this clutch work?
« Reply #82 on: October 19, 2018, 10:19:03 PM »
As promised, here are all the engineering drawings to fabricate this clutch.---Brian
http://www.mediafire.com/file/x7shbmds6box782/FRICTION_CLUTCH_BASED_ON_DRAGSAW.zip/file