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cenrtifugal clutch

cenrtifugal clutch

cenrtifugal clutch

HI Guys, new here and hopefully I can get some answers. Bud Warren ( RIP) has developed a  (http://www.geareddrives.com/PSRU_for_Subaru.htm) new type of centrifugal clutch/pressure plate, looking at the installation manual , I can't see how is possible to look up the clutch by centrifugal motion on that arrangement. Would appreciate, if there is some explanation.


RE: cenrtifugal clutch

Looking at the installation manual, it appears that the clutch uses a standard automotive dry clutch disc with damper springs.
The assembly differs from a car clutch in that it is not spring-engaged; it is spring-released, and engagement is done by means of bobweights on the clutch fingers.

I.e., centrifugal force acts on the "fingers" (the photos don't show exactly how), and as the engine spins faster, the fingers press on the pressure plate, which gradually clamps down on the clutch disc that is trapped in the space between the flywheel and the pressure plate.  As engine speed decreases, the force applied by the fingers is reduced, and at some point is overcome by the light springs shown in the loose pressure plate picture, so the pressure plate moves away from the clutch disc, and the prop is effectively disengaged from the engine..


Mike Halloran
Pembroke Pines, FL, USA

RE: cenrtifugal clutch

Thank you Mike , just have to work out how those fingers are able to look up the clutch plate.

RE: cenrtifugal clutch

Do you have a detail drawing or photo or illustration?
Find a finger's center of mass.  As that moves outward under centrifugal force, either a pivot or a cam surface must convert that to axial motion of some part of the finger toward the pressure plate.  That's how it _has_ to work.

Mike Halloran
Pembroke Pines, FL, USA

RE: cenrtifugal clutch

Hello Mike
Unfortunately don't have any illustration or drawing other that what is on the webpage. Thinking he would not have invented this and spend over 3 days looking at all the inventions, but dint find nothing even similar excepts the ball bearings pressure plate. There is another link, only made aware after your response on their web pages, perhaps if you care to look into could give you some more clues.  


I have spoken today with pretty clued engineer and he agreed with your assessment but still couldn't work of how/what does make to look up the clutch plate other to say this is mind bogging. Again, I do fully appreciate you help, and hopefully you would have the answers. Thanks
Take care

RE: cenrtifugal clutch

Did you find a patent number?

The patent _has_ to tell you how it works.


Mike Halloran
Pembroke Pines, FL, USA

RE: cenrtifugal clutch

I'm looking at page 7 of the owners manual for the LS1 version of the PSRU.
It looks like there is a radial post fastened to the periphery of the flywheel, which has a cam roller on its inboard leg, and that the 'counterweight' is forked to guide on one leg of the L, and must have a cam surface machined into one face that interacts with the cam roller to force the pressure plate toward the flywheel.

So far I haven't found a patent for such a thing.

Page 8 has a side view that shows the edge of the clutch disc, the pressure plate, and the radial post mounted to the flywheel.  Still no detail around the counterweight/cam roller interface.


Mike Halloran
Pembroke Pines, FL, USA

RE: cenrtifugal clutch


Thanks again, if this in not too much to ask could you please draw me a sketch to be able to understands this in a more objective way. I have done some drawings to your suggestions but it doesn't make any sence to me.


RE: cenrtifugal clutch

Yes, that's the document I referenced.  The U shapes are clearly wedges that try to fly out under centrifugal force.  I'm still guessing that the inside root of the U must have a ramp surface that interacts with a roller, or something, to exert force on the pressure plate.


Mike Halloran
Pembroke Pines, FL, USA

RE: cenrtifugal clutch

Much more sophisticated than the 'fly out' fingers on the centrifigual clutch on the motor scooter that was my transportation as a kid.  The springs kept the fingers pulled in at idle, but give her some gas.....


RE: cenrtifugal clutch

since the untimely death of Bud Warren and his wife, are these units even available anymore?

The good engineer does not need to memorize every formula; he just needs to know where he can find them when he needs them.  Old professor

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