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Revolutionary Engine Debuts @ Miami Show

Discussion in 'Technical Discussion' started by YachtForums, Feb 15, 2004.

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  1. YachtForums

    YachtForums Administrator

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    The Dyna-Cam.

    Prepare yourself for a look at the future...

    The engine is 13" in diameter, 40" long and weighs 265 pounds with basic accessories. It has unique features and major benefits over conventional engines of similar weight and power. The benefits include lower manufacturing costs in equal production, 50% smaller size, 50% fewer replacement parts, better fuel economy, smoother operation, lighter weight, plus nearly 100% higher torque enabling the engine to turn high efficiency propellers with lower noise output.

    The engine has two identical cylindrical blocks that each have six cylinders arranged parallel around the main shaft located in the center. Cylinders of both blocks line up so that six double-ended pistons can fire back and forth between the aligned cylinders of each block Each free floating piston is cut away on the central interior side and fits with precision around a 9" diameter, four lobe, sinusoidal cam that is keyed to the main shaft.

    As the pistons fire back and forth, the main cam rolls through the pistons causing the central shaft to turn. All moving surfaces are roller bearing surfaces. Another smaller 5" cam is attached to the main shaft at the outer end of each block. As each valve cam turns, it pushes against hydraulic lifters which push against the poppet valves inside each cylinder head.

    The engine is a 4-stroke engine. Because of the design of the main cam, each of the twelve cylinders fires with every revolution of the shaft, in contrast to three times with conventional six-cylinder engines. The engine can be described as a free piston, axially cam-drive engine.

    Specifications...

    12 Cylinder, 6 Piston
    13" Diameter x 40" Length
    265 Lbs Dry Weight
    373 Cubic Inches
    40% Less Friction Horsepower
    50% Less Components
    25% Quieter with similar exhaust systems
    20% More fuel efficient
    50% Less space required for installation
    Vibration Free Operation
    Assembled/Rebuilt in 1/3 time of conventional engines
    Liquid Cooled
    Fuel Injected
    Multi-Fuel use
    TBO of 2500 Hours

    Horsepower...

    Naturally Aspirated Rating of 200 Horsepower
    Turbo-Charged up to 350 Horsepower
    Turbo-Intercooled up to 450 Horsepower

    Torque & HP Ratings...

    200 HP @ 2000 RPM
    175 HP @ 1600 RPM
    650 ft.lb torque @ 1200 RPM
    525 ft.lb. torque @ 2000 RPM

    1100 ft.lb. torque w/ Turbo
    1400 ft.lb. torque w/ Intercooled Turbo

    Here is the first in a series of pictures....

    Attached Files:

  2. YachtForums

    YachtForums Administrator

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    The flip side...

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  3. YachtForums

    YachtForums Administrator

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    From another angle...

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  4. YachtForums

    YachtForums Administrator

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    The engine has six double-headed pistons which compress and fire at each end. As one end fires, it compresses the other end. This back and forth movement forces the roller cam to rotate and since the main shaft is keyed to the cam, rotational power is developed. Trunion rollers are housed in the middle of each piston that ride along the cam.

    The resulting engine operation has a pure harmonic motion and is so perfectly balanced that almost "zero" vibration is developed. Counterweights, vibration dampeners and flywheels are not needed!

    This internal drawing gives an idea of how the piston are positioned...

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  5. YachtForums

    YachtForums Administrator

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    There are many less moving engine parts in the Dyna-Cam, as compared to conventional engines. This engine has less than one-half the parts of other equally powered engines. There are two engine blocks (identical), six double-headed pistons, one main cam shaft, trunnion rollers, valves and valve cam thrust bearings. With the exception of the exhaust system and fuel system... that's it!

    Here's a picture of the parts...

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  6. YachtForums

    YachtForums Administrator

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    This is the DynaCam main engine blocks split in half...

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  7. YachtForums

    YachtForums Administrator

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    The DynaCam Engine has already been proven successful. The original developer, Dr. Karl Herrman, in conjunction with the Navy, spent millions developing and refining the design, which was used successfully to power Mark 46 torpedos for over 20 years.

    The design reached FAA certification in the late 1950's. By the 1980's, it was further refined, retrofitted with new accessories and successfully installed and demonstrated in a 4-place Piper Turbo Arrow.

    Over 40 prototypes have been built and tested. Hundreds of thousands of hours later, (40 years!) the engine has finally moved into production at Aero-Marine's new facility located in Ronkonkoma, New York.

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  8. John B

    John B Senior Member

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    Does this mean all four strokes (intake, compression, power and exhaust) occur in each revolution? :confused:

    I can't picture that. A four stroke needs two revolutions to complete all four strokes. Or is this what the 'main cam' is doing (unlike a cranksaft)?
  9. Ben

    Ben Senior Member

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    I think what they are refering to is that each piston in a normal 4 stroke fires every two rev's of the crankshaft, because this engine has double ended pistons, each piston can effectivly fire every rev'.

    At the risk of sounding a little crude, one end is "s u c k - squashing" while the other end is "bang - blowing" (s u c k , squash, bang, blow = 4 stroke ;) )
    Last edited: Mar 21, 2005
  10. brian eiland

    brian eiland Senior Member

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    Fuel Type?

    Maybe I missed it, but I've not been able to determine the fuel type for this engine. Can it use diesel rather than some more highly explosive fuels that we don't care for on boats?
  11. catmando

    catmando Senior Member

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    It says 'multi-fuel use' so that could include JetA, kerosene, biodiesel, etc. as well as gasoline. Where was that booth? I walked all over the convention center inside and out and I didn't see it. :(

    The intercooled turbo motor will find many different applications, especially in the 20'-30' range. Look out Mercury!! :p :D
  12. YachtForums

    YachtForums Administrator

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    The pictures and information were gathered at the 2004 Miami Show. The thread was bumped to the top of the forum by Ben's post.
  13. Ben

    Ben Senior Member

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    I knew it was an oldie, I just didn't have the heart to tell 'em :eek: :p

    John's question hadn't been answered, so I thought I'd have a go, just incase he was still interested. :rolleyes:
  14. YachtForums

    YachtForums Administrator

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    That's OK Ben...

    It was a good idea to bring this thread back to the surface. It's an interesting subject. :)
  15. brian eiland

    brian eiland Senior Member

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    Multi-Fueled definition

    I beleve the term 'multi-fuel' is possibly overused here, and it does not always refer to the total available fuel spectrum. Diesel fuel usage usually requires some substantial higher compression ratios so as to not require an ignition source. I think I detect an ignition distributor in the photos. And I don't know of many, or any certified diesel fueled small aircraft engines.

    If they appeared at a marine show, one would think they would most definitely pronounce the use of diesel fuel, which they do not to my knowledge....just my observation
    Last edited: Mar 23, 2005
  16. Codger

    Codger YF Wisdom Dept.

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    3 years later... a Diesel.... and some other activity.

    "......NEW DIESEL / MULTI FUEL ENGINES

    We are in the final stages of dynameters test trials performance data gathering in Detroit on our prototypical 8 cylinder, 7.2, 352HP "Work Horse" diesel /multi fuel engine which produces 1,140 ft lbs of torque.

    This engine and the Gas-Cam engine share many common design features. A sinusoidal cam rather than a crankshaft was used to convert the linear motion of the pistons into rotational motion in the drive shaft. The engine contains substantially fewer parts and therefore is much lighter than an equivalent conventional engine. This engine has a very high torque of 3.2 ft-lb per HP. This is 75% greater than an equivalent displacement 7.2 liter 6 cylinder Caterpillar diesel engine. The fuel performance is also better than the Caterpillar. This AVE engine is designed for 40,000 hours of operation between major overhauls. If this engine was placed in a truck, and it was driven at 50mph, you could expect to travel 2,000,000 miles before the next overhaul or 75 trips around this planet. A Digital Signal Processor manages this engines performance. There is a number of interesting new features design into this new AVE engine....."


    http://www.axialvectorengine.com/about_history.html


    And after all this time there's something going on.
    http://www.sec.gov/Archives/edgar/data/1144130/000111776807000162/mainbody.htm
  17. brian eiland

    brian eiland Senior Member

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    Revetec Engine

    Here's another very interesting engine without connecting rods. WHen I first read the description of the Dyna-Cam engine I was picturing the opposed piston arrangement of the revetec engine.


    I brought this subject up under the "Air-Electric Drive" posting at:
    http://www.yachtforums.com/forums/35854-post35.html
    ...but no one responded


    Revetec Engine
    http://www.revetec.com/
    http://www.revetec.com/development.htm


    Here is another forum discussion with more reference websites:
    http://www.boatdesign.net/forums/showthread.php?t=9878

    I wonder which arrangement might last longer, the sinusoidal cam/crankshaft of the Dyna-Cam verses the “trilobate” (three lobed) cams of the Revetec??
  18. Codger

    Codger YF Wisdom Dept.

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    Thanks Brian.
    I have not looked at the "Air -Electric Drive" thread for a while. Seemed to be a lack of consensus as to the utility/reality of that system.
    The Dynacam at least has been shown to work. Last night I realised that I hadn't heard anything about it for a while so looked back and found this old thread.


    " I wonder which arrangement might last longer, the sinusoidal cam/crankshaft of the Dyna-Cam verses the “trilobate” (three lobed) cams of the Revetec??"

    I've thought about this as well in regards to the Dynacam. In conventional diesel engines the maximum stress/wear points in the system have long ago been identified and dealt with, more or less, by materials/lubricant developments. I don't know if there are higher forces present between any of the faces in the Dynacam or the Revetec than have already been dealt with in conventional diesels or even if the materials/lubricants are really issues.
    I would be surprised if some of the major manufacturers of engines have not built a mule or three of these engines and come to their own conclusions. The chances of that information being available outside those companies is slim to none.
    The "not invented here" factor as a reason for not looking at different technologies is for the most part a thing of the past. I've heard the conspiratorial "bury the technology" story too many times and now just refer to the investments in Ballard that the automotive industry has made to zero that one.
  19. brian eiland

    brian eiland Senior Member

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    I still have great reservations about that myself...just seems to go against all physics we learned.

    I've followed this Revtec development for awhile, but not as throughly as I would have liked to (I still have a bunch of related forum discussions from some knowledgeable engine folks on my computer that I've not had time to read yet). One thing I've noticed over the period of time is their addition attention to the rollers/trilobate cam interfaces. so there must be extra wear problems they are finding and addressing. I don't believe this has been fully addressed on the dynacam engine. what bothers me is "trunion rollers are housed in the middle of each piston that ride along the cams". Their claims of '2 million miles' seem unfounded to me.

    Remember in both of these cases the cam following bearings and cam faces are having to absorb the power of the iginition explosion rather than just being conventional valve activation units as in conventional engines.
  20. Codger

    Codger YF Wisdom Dept.

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    I really do try and keep an open mind about new technologies and developments. Have had a lifelong passion for machines. For some reason many of those claiming to have new technologies make statements that just make it very difficult for me.
    "This AVE engine is designed for 40,000 hours of operation between major overhauls. If this engine was placed in a truck, and it was driven at 50mph, you could expect to travel 2,000,000 miles before the next overhaul or 75 trips around this planet."
    This is a perfect example. Real world, what truck actually runs at 50mph?
    That sort of statement immediately makes me more than a little bit suspicious.
    Run a 671 at a constant load at optimum speed and the darn thing could probably circumnavigate the solar system if the roads were there. Who gives a ****? Motors just don't get that kind of a life.
    End of rant.

    Brian, I agree with you on the trunion rollers in the Dynacam. They are getting the bejesus whacked out of them. Have they looked at ceramics to lower the mass? Have they looked and then found out that the costs of the materials required to deal with the problems make the whole deal a non-starter except for the military? Too many questions and not enough answers.