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Old 03-15-2017, 06:19 AM   #1 (permalink)
DieselJan
Less waste = better FE
 
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Shock storing conrod arm mod

I have been thinking for a while about a way to change an internal combustion engine to make it more fuel efficient. This mod to the conrod is the simplest/cheapest implementable solution I came up with.

I am now asking for comments why it can or can’t work. As far as I could think everything through it should work. But I probably haven't thought of everything.

The idea, as can be seen on attached "artist" drawing, is to put a spring on a conrod arm, and split the arm in 2 so that it is compressible. The spring can store the energy shock at peak combustion, and give it back to the crank shaft after TDC. This will increase torque and reduce fuel consumption.

It will also solve a few problems associated with internal combustion engines.
1) Reduce/eliminate NOx in diesels as peak combustion temps will be lower.
2) Eliminate detonation (ping) in petrol engines.
3) Probably have a cleaner burn with reduced wasted exhaust gasses.
4) Engine parts can be made smaller/lighter as peak combustion will be lower.
5) Have more torque as there will be more pressure on crankshaft after TDC which was stored temporarily in spring.
6) Timing can be advanced more leading to better combustion and improved fuel consumption without damaging the engine or having bad exhaust gasses.
7) Quieter engine operation with less shock and vibration and wear.
8) Less wasted heat going into cooling fluid as combustion temps are lower.

Disadvantages I can think of.
1) Conrod arm will be heavier. This can be compensated with lighter crankshaft and lighter piston.

A bit about the drawing. It is just a concept for explanation. I am sure it can be improved. I don't have all the knowledge of what type of spring strength is needed, but I am sure someone can work it out.

The conrod arm is made of 2 pieces, which fits into each other. The pieces shouldn't be able to twist in each other, as it will break the swivel point on the piston. A pin through the top conrod will slide in the slot on the side of the bottom conrod. This will stop the spring from pushing the two conrod pieces apart. At the top of the spring there is a piece of metal to hold spring so that it doesn't interfere with the swivel point at the piston.

An oil channel runs from the big end to a hole connecting it to a slot along the top conrod arm. This slot in the top conrod will always be connected to the hole opening in the bottom conrod. So as the top conrod slides into and out of the bottom conrod, there will always be a path through for the oil to the piston. The oil volume will also not change as the compression / expansion happens. This oil will also lubricate the sliding surfaces between the conrods.

If the pin in the top conrod is made better to stop the two pieces twisting in each other, the conrod arms could be made from round metal. I was just concerned about wear on the groove and pin of the top and bottom conrod arms respectively. So I drew it with square pieces fitting into each other.

Please comment on what you think the problems associated with this design is or how it can be improved, I would like to know if it can work. After that we can start messing with lawn mowers, etc. to test it.

Jan


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Last edited by DieselJan; 03-15-2017 at 06:32 AM.. Reason: Try to move it out of aerodynamics
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