I have seen engines where there is one cylinder and one piston but each end of the cylinder is a combustion chamber. The engine fires on both sides of the piston. This interested me so I looked deeper into the design and found there are several engines using this system and at first glance I thought I can make this. No problem.
Boy was I wrong as this design brings up several major problems. At first I thought I could just treat each end of the cylinder as a separate 4 cycle engine and use a distributor to control the spark. Use a side shaft with two cams at a 2 to 1 ratio of the crank shaft for the exhaust valves. What I found was that no mater how you configured the valve timing there would be a cycle when one side had fired and the other side was starting into compression. Most of the power from the first side would be lost.
Back for more research and found that several of these engines use 6 cycles.
Power
Exhaust
Exhaust
Exhaust
Intake
Compression
Yes the exhaust valve is held open for 1 1/2 revolutions or 3 strokes but you have to remember that there are two combustion chambers and as they overlap so the idle time is not too long. There are other ways of making a 6 cycle engine also but this is the way I'm going to attempt to do it. Attempt is right as there are many different operations I have never done before such as the valve timing for the 6 cycles.
The cam shaft now will make one revolution for every three revolutions of the crank shaft.
I'm just going to jump right in and see how it goes.
I salvaged a nice 10mm shaft from a hydro window opener or supporter.
I turned a piston from a piece of aluminum and with a light press and some red loctite positioned it in the center of the rod.
I bored 2" aluminum cylinder to 1.250 inside diameter for a nice piston fit.
I did make a rudimentary drawing of what it might look like.
Thanks for looking
Ray
Boy was I wrong as this design brings up several major problems. At first I thought I could just treat each end of the cylinder as a separate 4 cycle engine and use a distributor to control the spark. Use a side shaft with two cams at a 2 to 1 ratio of the crank shaft for the exhaust valves. What I found was that no mater how you configured the valve timing there would be a cycle when one side had fired and the other side was starting into compression. Most of the power from the first side would be lost.
Back for more research and found that several of these engines use 6 cycles.
Power
Exhaust
Exhaust
Exhaust
Intake
Compression
Yes the exhaust valve is held open for 1 1/2 revolutions or 3 strokes but you have to remember that there are two combustion chambers and as they overlap so the idle time is not too long. There are other ways of making a 6 cycle engine also but this is the way I'm going to attempt to do it. Attempt is right as there are many different operations I have never done before such as the valve timing for the 6 cycles.
The cam shaft now will make one revolution for every three revolutions of the crank shaft.
I'm just going to jump right in and see how it goes.
I salvaged a nice 10mm shaft from a hydro window opener or supporter.
I turned a piston from a piece of aluminum and with a light press and some red loctite positioned it in the center of the rod.
I bored 2" aluminum cylinder to 1.250 inside diameter for a nice piston fit.
I did make a rudimentary drawing of what it might look like.
Thanks for looking
Ray
