Printable View
WWII-era Bristol Hercules radial engine gear train.
https://s3-us-west-1.amazonaws.com/h...n_fullsize.jpg
https://s3-us-west-1.amazonaws.com/h...1_fullsize.jpg
Previously:
https://www.homemadetools.net/forum/...085#post168585
https://www.homemadetools.net/forum/...772#post174983
https://www.homemadetools.net/forum/...286#post172912
https://www.homemadetools.net/forum/...539#post173982
https://www.homemadetools.net/forum/...992#post168156
https://www.homemadetools.net/forum/...529#post142982
Amazing engineering
Oh My Gosh!
One chipped tooth and it's all over...
It is indeed amazing. Designed in someones head, on a board, with pencils and instruments, no CAD or computer simulation for assistance. Then built by real machinists, with no CNC, who were under tremendous pressure. Assembled by hand with each gear messed properly with its bothers and sisters.
Having never seen one before, I was having trouble finding the valve train. All I could see were ports open into the side of the cylinders. It had me thinking surely it cannot be 2 cycle.
Discovered this explanation for that extensive gear train.
https://www.youtube.com/watch?v=_vrvep_YOio
Here is an attempt at a scale model of this engine.
https://agelessengines.com/sleeve.htm
That is impressive. That guy is a little bit crazy.... in a good way.
Knight sleeve valve engine...
https://www.youtube.com/watch?v=NSMYjRNQ8Rs
An extremly intricate valve system for virtually no gain in power but a slightly lower engine weight of 1925 lb (strangly enough). The Hercules power output was 1375 hp from a 2360 cu in engine. The closest I could find readily was the Curtis Wright R-2600 which put out about 1500 hp at a weight of 2054 lb. The valve timing on a sleeve valve engine was more involved than assembling an old Swiss watch although the poppet valve engine had timing gears and a set of cam rings with lobes to lift the cam followers. I think that the close proximity of the Hercules spark plugs was one reason for the reduced power output of this type, even though the port openings on a sleeve valve engine was bigger than on an equivalent poppet valve engine.
Many Thanks for posting. Brought back many memories. Complicated, British of course, but reliable. Drank a lot of oil compared with a Pratt or Wright engine.
Rangi.
That thing has more moving parts than the Radio City Rockettes!
The DH Gypsey Major was nicknamed the Dripsey Major and British motorcycles were renowned for oil leakage. Jokes ran along the lines that you were supplied with an umbrella if you needed to board a British propliner from under the wings.