Manson engine

Some young dark/gothic style fans visualized a tall, lean, out-of-line figure from the early 90's, 
who created a new style of R'n'R! :)
No, no, no!
The Manson engine is an open cycle hot air engine from 1952, designed by A.D.Manson.
( As you can see, not Marylin :P )
How does it work?
It is so simple like every other hot air engine.
Start to heat up the air in the engine and it will expands. 
This expansion can move out the piston from the cylinder. 
And when the air is cooled then the piston will move back. 
The original Manson engine had one moving part, it was a "2 in 1" piston. 
The displacer piston moves with zero angle difference with the power piston.
They move together because the pistons are connected directly to each other.
(In the Stirling cycle this angle is 90 degrees usually.)
Animation from this site:

The engine has 2 power strokes. 
1. expansion stroke: when the internal pressure exceeds the outside (athmospheric) pressure the piston is pushed outward.

2. vacuum or suction stroke: it follows the expansion stroke continously.
At the end of each stroke, a valve is opened to the athmosphere 
and thus the engine's internal pressure is restored to the middle pressure (athmospheric as usual) 
and the cycle may start over again and again...

The power piston has a respect ratio of the displacer diameter 
for the most work from the expanding air.
This optimal ratio is 46% 
Power piston/ Displacer piston.
 If the piston's diameter is smaller then the engine will have less force.
If it is too large then it will occupy too much volume from the cold side 
and only a few air will left there.

Picture from: 

This engine is so simple and it has a big torque.
I like it so much! :)

More information from this original version, and other developes here:

My opinion from this construction:
Wrong regeneration and also heat exchange, slow strokes, large size!

The regenerator gap between the cylinder and the displacer 
should be 0.8 mm for every 25mm diameter of the displacer. 
It is a simple solution for the regeneration, but the regenerator gap's efficiency is too low.
The small gap is working against for the air flow also.

The last invention that is patented is the Rupp engine.
It is a cold side ventillation Manson type engine with smaller dead volume.
Nice modell engine but it could be better!
Much more better!
Check the Kovács engine's topic!
(under construction)