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Beta Rhombic Drive Motor

Posted: Sat Mar 23, 2019 5:54 am
by Vjdeep
hello,
i made a post regarding my beta stirling engine a couple of days ago.

http://stirlingengineforum.com/viewtopic.php?f=1&t=2386

I have made a few minor changes and have greatly reduced the friction present in the motor.
but, it is not working inspite of the changes made. I have added video of the stirling motor. Any advice and help would be greatly appreciated and helpful.
https://www.youtube.com/watch?v=BYJr1dfnXSM
https://www.youtube.com/watch?v=Dt_k27tsprY


Changes made since last post
The linear of the cylinder has been changed to cast iron(this has drastically reduced friction and increased piston play and sealing) and a Standard piston (along with piston rings) of the linear has been used for power piston.
the weight of the gears has been vastly reduced and the flywheel has been changed to one with higher moment of inertia.

Re: Beta Rhombic Drive Motor

Posted: Sun Mar 24, 2019 2:52 am
by Ian S C
Vjdeep, what is the piston made of? It is best if no rings are used, but a close fit in the bore. Piston rings cause high friction on the cylinder wall, and only really work properly with the high pressure if an IC engine, or the steam of a steam engine, even there the spring pressure against the cylinder has to be regulated according to the pressure of the gas/steam in the engine.

One way of dealing the piston is to fit a leather cup seal, similar to what is fitted in some water pumps.

This is the piston and con rod for my stove top engine. the gudgeon and con rod are screwed into the under side(hollow) of the piston, the dark disc(the leather cup seal) is placed on top of the piston, and retained by the retaining nut at the bottom of the photo, the two small holes are for a special pin wrench(you make your own to fit). In this case it gave no improvement as the piston was a good fit, I just thought I would try it out.
Ian S C

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