TwoBanger2B

[Coilmotorworks]

The prototype and some of the parts of the twin version. The design is based on an Atkinson cycle gas engine. The difference is that these motors produce two power strokes per revolution. More to follow...

CMW

 

[Coilmotorworks]

This is the nearly completed motor. If it works properly, the video shows the motor in a per-skeletonized state. I need to install the variable voltage DC controller and battery pack. This motor will idle on 2VDC and will auto start because there is always a solenoid in the pull position no matter where the crank is.

[ame]http://youtu.be/mJHDz469SbU[/ame]

 

[jerrybilt]

Once again very nice. Nice construction. Flywheel in the top photo is impressive - very skilled indeed. Have you tried to make a Mendocino Motor ? This would be right up your ally.

 

[Coilmotorworks]

I think the flywheel on the prototype came from PM Research as a raw casting. it is just the right weight (it's aluminum) for the motor as it is a low torque motor. The twin uses a brass flywheel but is much smaller in diameter.

I am working on a fly-ball type governor that will control the shutoff point of the contacts so speed could be mechanically adjusted and automatically controlled. The biggest problem is that the adjustment range is very small so the governor must be very sensitive. Due to the size of the motor the problems compound when trying to build a working governor. Oh well, that's the fun in all of this anyway.

I just want to add that the cam lobes for this motor are not 180 degrees. Due to angularity in the linkage to get the stroke length even top to bottom the lobes are offset a few degrees to compensate for the difference when the solenoid is in mid stroke during 1/8 & 5/8 part of one revolution.

 

[jerrybilt]

First things first. Congratulations on getting the new lathe. Did you do all the " non round" pieces like frame work crankshaft etc using a saw and a file? Looking at the pictures ... Excellent job!

About a governer: the ball type will do the job and there will be so much " eye appeal" and here is a suggestion, as the motor is electric use a small potentiometer ( small infinite resolution ones used in control have nice bearings and low friction) and a swash plate fixed to the ball governor shaft to do the speed control.

Cams are not difficult to design by hand ... Need a compass, protractor and a ruler and with your filing skills you should be there.

You will find this interesting and most useful in the design of the governer: Graph the position of the pistons ( 2 graphs) over 1.5 revs of the shaft, this will guarantee one complete cycle, and you can use this graph to determine swhtching control points and how sensitive this would be ... The solenoids may be energised for a longer part of the cycle so there will be an optimum dwell time. There will be two commutators, one for each cylinder so this diagram will help in setting up the timing ... Good luck.
Jerry.

 

[Coilmotorworks]

Jerry,

Maybe some background on me is in order:

I have had a lathes for over 20 years. Wished I could afford a new 12 X 36 with all of the tooling. I take donations (grin!).

I used a Taig and Sherline lathe for the round stuff, solid one piece crank and the complicated trunnion. I used a Sherline 5400 mill to cut out and make all of the other parts you see in the pictures. The only thing I used the file for was removing sharp edges. I used a hack saw to cut the large pieces to length. all of the skeletonizing was done on the mill. The need for high precision was very important as any binding and this motor would not run. I have over 100 hours into this motor which includes design and number crunching time.

Cams are no problem. I have lots of experience timing solenoid motors, been doing it since 1984.

I've made good working small fly-ball governors in the past, here is an example of one of my more recognizable ones that is about a 1/4" tall!

[ame]http://youtu.be/1UiPdkCwDIc[/ame]

I am sticking to a mechanical design for adjusting the speed. I will post the design when finished. It will make total sense when you see it. I just need some time to do the number crunching and then cut it all out and make it work.

It's all good.