Jan Ridders
Well-Known Member
- Joined
- Apr 21, 2008
- Messages
- 52
- Reaction score
- 94
Hi all,
I made a design for a 4-stroke model IC engine without gears or timing belt for the 2 to 1 distribution.
Each 4-stroke engine has a transmission ratio (distribution) of 2 to 1 between the crankshaft and the camshaft for the valve system and spark control because the crankshaft makes two revolutions for the four piston strokes (intake, compression, combustion and exhaust) while the valves and the spark only once are controlled during the process cycle. This distribution is typically made by interlocking gears or with a geared timing belt over two toothed wheels, wherein the sprocket on the camshaft has two times more teeth than the one on the crankshaft.
In itself a good and proven system, but sometimes it is a problem for model builders to make or buy the appropriate gears and that can be also the case for a small and flexible geared timing belt. For me this was a provocation to see whether it is possible to make such a distribution system without gears or a timing belt. It is fair to say that my eternal desire to "do it differently" also played a role while only the challenge is important other than the practical meaning of the design. I can not leave that way of working and I suspect this is a kind of professional deformation that I gained during my 40-year working life as a process developer.
You can follow my escapades on the concerning page of my web site:
http://ridders.nu/Webpaginas/pagina_drukviertakt/druktviertakt_frameset.htm
Friendly regards from Holland,
Jan Ridders
I made a design for a 4-stroke model IC engine without gears or timing belt for the 2 to 1 distribution.
Each 4-stroke engine has a transmission ratio (distribution) of 2 to 1 between the crankshaft and the camshaft for the valve system and spark control because the crankshaft makes two revolutions for the four piston strokes (intake, compression, combustion and exhaust) while the valves and the spark only once are controlled during the process cycle. This distribution is typically made by interlocking gears or with a geared timing belt over two toothed wheels, wherein the sprocket on the camshaft has two times more teeth than the one on the crankshaft.
In itself a good and proven system, but sometimes it is a problem for model builders to make or buy the appropriate gears and that can be also the case for a small and flexible geared timing belt. For me this was a provocation to see whether it is possible to make such a distribution system without gears or a timing belt. It is fair to say that my eternal desire to "do it differently" also played a role while only the challenge is important other than the practical meaning of the design. I can not leave that way of working and I suspect this is a kind of professional deformation that I gained during my 40-year working life as a process developer.
You can follow my escapades on the concerning page of my web site:
http://ridders.nu/Webpaginas/pagina_drukviertakt/druktviertakt_frameset.htm
Friendly regards from Holland,
Jan Ridders
