Crankless Internal Rotating Cylinder Engine (CIRCE)
I have seen a few engines based on the following design :-
Uncredited / Unknown Source Photo
And decided to design my own version by eliminating the crank by placing the cylinder within the flywheel – hence CIRCE – Greek goddess of magic.
Attached is the resulting design – the primary flywheel (or “Crankwheel”) has to run in a cradle of ball bearings and be held into that cradle by a further pair of bearings running against the inclined inner surface at 45°.
The cylinder is 16mm bore x 30mm stroke.
Assembly without the rotary cylinder – the Crankwheel can be removed after adjustment of the inclined bearings by removing one of the inclined bearings (after adjustment - which is easier before assembling the cylinder in place).
The G.A. Drawing.
The drawing and these build notes are available at the HMEM website :-
And a video of it running on YouTube:-
Cross Section:
The dimensional data in the AutoCad drawing is correct – in the case of the Chassis Plates can be used for laser cutting.
Airflow Diagram:
This is how the inlet / exhaust is commutated by the collector ring and distributor axle :-
The annulus grooves in the distributor axle
The “blind” zones (there is another on the opposite side) between grooves transits past the inlet/exhaust ports when the cylinder is vertical – commutating the inlet to exhaust and vice versa at the transition.
Note: In the main cross section drawing the axles is shown out of position by 90° to illustrate the porting rather than physical orientation – FYI to avoid confusion.
Attached the AutoCad *.dwg files and a *.pdf of the build notes.
The *.zip file contains the *.dxf & *.docx versions
Files updated to correct error pointed out by Johnmcc69 - pitch between axles should be 98.2
Regards, Ken
I have seen a few engines based on the following design :-
Uncredited / Unknown Source Photo
And decided to design my own version by eliminating the crank by placing the cylinder within the flywheel – hence CIRCE – Greek goddess of magic.
Attached is the resulting design – the primary flywheel (or “Crankwheel”) has to run in a cradle of ball bearings and be held into that cradle by a further pair of bearings running against the inclined inner surface at 45°.
The cylinder is 16mm bore x 30mm stroke.
Assembly without the rotary cylinder – the Crankwheel can be removed after adjustment of the inclined bearings by removing one of the inclined bearings (after adjustment - which is easier before assembling the cylinder in place).
The G.A. Drawing.
The drawing and these build notes are available at the HMEM website :-
And a video of it running on YouTube:-
Cross Section:
The dimensional data in the AutoCad drawing is correct – in the case of the Chassis Plates can be used for laser cutting.
Airflow Diagram:
This is how the inlet / exhaust is commutated by the collector ring and distributor axle :-
The annulus grooves in the distributor axle
The “blind” zones (there is another on the opposite side) between grooves transits past the inlet/exhaust ports when the cylinder is vertical – commutating the inlet to exhaust and vice versa at the transition.
Note: In the main cross section drawing the axles is shown out of position by 90° to illustrate the porting rather than physical orientation – FYI to avoid confusion.
Attached the AutoCad *.dwg files and a *.pdf of the build notes.
The *.zip file contains the *.dxf & *.docx versions
Files updated to correct error pointed out by Johnmcc69 - pitch between axles should be 98.2
Regards, Ken
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