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The four-stroke engine with rotary cylinder block

  1. Aug 10, 2005 #1
    The cylinder block of traditional four-stroke engine can't move ,and it needs a complicated valve mechanism with large frictional losses and great noises to finish the the working cycle. Also because the journey of entering the intake system is long and the exist of the detour that causes the efficiency of entering is low ,which influence the power of the engine seriously. The four-stroke engine with rotatory cylinder block which I invented, has a simplier valve mechanism , therefore lower the noise , reduce the friction loss , shorten the journey , make that there is not a sharp turn, therefore can improve the efficiency of entering, improve the power of the engine .
    This invention includes the cylinder block, the cylinder cover, the piston and spark plug. The difference is that the cylinder cover is a hollow round cylinder and has a cankshaft in the centre, the sides of which are the inlet valve and exhaust valve.The cylinder block is connected with the crankshaft, which is divided into 3 cylinders.The cylinders regard cankshaft as the center to arrange radially at an angle of 120 ,and there is connecting rod inside which link to the crank.The transmission ratio between crankshaft and cylinder block is 3:1.
    This invention does not need complicated valve mechanism , has litter friction loss and lower noise , of simple structure, and its processing does not need special-purpose mechine tool . Because the rotational inertia of cylinder block is heavy, it does not need to design flywheel specially , which make this invention costs lower. The carburetor is linked to the cylinder cover directly with no shape turn and higher efficiency , improving the power of the engine . Analysed that can know by mechanics, the resultant of forces of first order rotating force of three cylinders is constant and along the direction of the crank outwards, therefore this force can be offset by arranging a equalizer on the crank . So this invention can cut down one shake as zero in theory .
    The four-stroke engine with rotaty cylinder block cycle principle of opertion is shown from Fig.1 to Fig.4.Fig. 5 is crankshaft and cylinder block transmission principle. In Fig. 1, cylinder block 3 is in the cylinder cover 2, the cylinder block is divided into three cylinders , inlet 1 and exhaust 7are on the two sides of the cylinder cover , the inlet is a slot, which is at the place where cylinder is passing when the piston 5 travel down from TDC to BDC on the first stroke. The exhaust is a slot too,which is at the place where cylinder is passing when the piston 5 travel down from BDC to TDC on the fourth stroke. 6 is the connecting rod in the picture, 9 is the crankwshaft. 0 degrees of air cylinders in position are the first jar in Fig. 1, taking this cylinder as an example to explain the woking cycle. Because the transmission ratio between crankshaft and cylinder block is 3:1., when the crankshaft is rotated from 0 degrees in Fig. 1 to 270 degrees in Fig. 2, the cylinder block is rotated from 0 degrees in Fig. 1 to 90 degrees in Fig. 2.At this moment,the piston travels down the cylinder from TDC to BDC and the cylinder block aims at the inlet valve to finish the introduction stroke. When the crankshaft is rotated from 270 degrees in Fig. 2 to 540 degrees in Fig. 3, the cylinder block is rotated to 180 degrees and the piston travels from BDC from TDC, finishing the compression stroke. The first cylinder aims at the spark plug at this moment, lighted a fire by the spark plug. When the crankshaft is rotated from 540 degrees in Fig. 4 to 810 degrees, the cylinder block is rotated to 270 degrees and the piston travels from TDC from BDC, finishing the combustion stroke. When the crankshaft is rotated to 1080 degrees, the cylinder block is rotated to 360 degrees and the piston travels from BDC from TDC and the first cylinder aims at the exhaust valve to finish the exhaust stroke.
    Using a epicyclic gearing illustrated in Fig. 5 can make the transmission ratio is 3:1. Gear 10 is the interal gear located in the cylinder cover, gear 11 is fixed on cylinder block 3 by planetary shelf 13 .Gear 12 is fixed on crankshaft 9. The tooth of gear 10 is two times as the tooth of gear 12,then the transmission ratio of the epicyclic gearing is: i =1-(-2Z/Z) =3 (Z is counted as the tooth of gear 12).
    This engine has already applied for the patent for invention, the application number is 936107565. 3, the publication number is CN1083172A.
  2. jcsd
  3. Aug 10, 2005 #2


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    Looks like a combination of a Radially Piston-Oriented Otto Cycle and a Rotary Wankel cycle. Where your rotating cylinder would be the rotor in the Wankel Cycle and your pistons could be the changing air pockets between the rotor and the Can't-think-of-the-proper-name-of-the-shape-of-the-outside, if you know what I mean.

    Have you been able to get an efficiency out of this engine? If so, how does it compare to Wankel cycle?
  4. Aug 10, 2005 #3


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    Sorry if I've missed out on some details. How is the cylinder cover rotated? How are (what would be the equivalent of the) dwell times adjusted? How do exhaust and inlet manifolds connect? How do the injection and ignition systems fit into all of this? How do you get a gastight state between the cylinder cover and the engine block? How do you account for the bulky nature of such an engine? How do you make the rotating block light enough to allow free revving?
  5. Aug 10, 2005 #4


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    I must admit this is an interesting idea. It seems you have been working it a lot of time. I give you a congrats, despites your engine would be industrially useless, inasmuch the centrifugal turning of the whole would destroy the cared combustion and fluid dynamics inside comb. chambers. As Brewnog has pointed also, you would have to find such cylinders block which have very little inertia, and that's a difficult business due to the additional material for cooling that cylinder cover needs. The fact that everything seems to be rotating (except the external round wall), makes the stuf very rotationally unstable and prone to vibrations.

    Keep on thinking of it. It's worth a comment. :approve:
  6. Aug 10, 2005 #5


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    That certainly is a neat idea. I was afraid at the beginning of your post that it was going to be some nut-bar gizmo. As others pointed out, there are some obstacles that would have to be overcome to make it practical as an industrial design, but it sure would be cool to have a working model to play with. If you get one built, post some video of it running. (And in a form that my Mac can read, if you please.)

    edit: I have to go to work now, but I just thought of something. If the rotating mass is too great, consider using a sleeved block made out of aluminum, Torlon, maybe even carbon composite—something light with a high temperature tolerance.
    Last edited: Aug 10, 2005
  7. Aug 10, 2005 #6
    I did not read your whole post, but it sounds very similar to this engine that is already been out on the market.


    Worth taking a look at, at least.
  8. Aug 10, 2005 #7
    The problem with your statement is the fact that, over the years, several similar designs have been built that have worked quite well.

    The problem that these engines have with inertia is similar to that of the Gas Turbine. They don't accelerate or decelerate quickly.

    Actually, just the opposite, if it is well balanced. His biggest problem, even if it works well, is the NIH (Not Invented Here) factor. Present producers won't buy it unless it yields far less pollution, or is far more efficient, and since it is still an Otto Cycle engine, that is extremely unlikely. There are well over a century of experience with the present piston engine design; manufacturers are comfortable with it; and they will be highly resistant to invest great amounts in the development of a new configuration, unless they get an offer they can't refuse. Best luck anyway.

  9. Aug 11, 2005 #8


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    WoW Kenneth :bugeye: ! You seem to look at my words with magnifying glasses!!.

    The problem with your statement is the fact that over the years several similar designs have been built, but none of one have worked properly. Only traditional Otto, Diesel and sometimes Wankel engines work well, and it's not because any conspiration as you have mentioned, it's because these designs have been broadely studied and calculated by many people. By the way, their performance in the fluid dynamics stuff have been achieved in such a way that any proposed advance from laboratory takes 15-20 years to reach the market.

    I don't think so. A gas turbine rotor is more balanced that the engine shown here. It's a question of common sense and periodic axilsymmetry of the gas turbine.

    This last statement makes no sense. I mentioned that a disbalance inertia rotating is one of the problems of this design. Actually just the opposite? :surprised
  10. Aug 11, 2005 #9
    These statements cannot be allowed to go unchallenged!

    Absolutely false!

    I challenge you to find any studies that have found any of the following designs to be unable to function properly. If you know of any, or if you can do so yourself, we can inform the people who are making these, and I'm sure they will stop wasting their time when you have enlightened them.
    http://www.machaon.ru/tetra/veselo.htm [Broken]
    2. A Rotary Brayton-Cycle Engine
    3. A (Gas Turbine) Brayton Cycle Engine
    http://www.saintjohn.nbcc.nb.ca/Heritage/bricklin/Rotary.htm [Broken]
    5. An operational Stirling-Cycle Engine
    6. An Axial Rotary Otto Cycle Engine

    By the way, I don't recall anyone mentioning conspiracies. The engines (or any other invention, for that matter) are simply ignored. As you get a bit older, you'll understand the NIH factor and other things in the psychology of the 'real world' better.

    If by this you mean that it will take years to get a properly working model out; of course it will. It always does. It took the presently popular Otto and Diesel cycle configurations much longer. That time factor is their advantage, and manufacturers are not about to drop designs that they have invested so much into. As far, however as the present Otto and Diesel cycles being the 'best of all possible designs' - - - RUBBISH!

    And, they are all better balanced than the present Otto and Diesel cycle designs. So What?!!!

    And if it is a problem with this design, it's a monster problem with the old Otto/Diesel cycle designs that we all know and love so much; and it's still an inertial factor.

    Last edited by a moderator: May 2, 2017
  11. Aug 11, 2005 #10


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    Thought some of you might want to have a look at this: http://en.wikipedia.org/wiki/Rotary_piston_engine

    http://www.keveney.com/gnome.html [Broken]

    This stuff isn't really new at all. However, improvements can be made with just about anything.
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  12. Aug 12, 2005 #11


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    Man, that Gnome is a freaky critter—I love it!:biggrin:
    Zhan... (pardon the familiarity of address; I'm too lazy to type your whole name);
    Since there was nobody around to talk to in the bar tonight, I applied some additional thought to your design. This is based upon the assumption that it's a thick disk, somewhat like a large hockey puck (hey, whaddaya expect from a Canuk?) It occurred to me that if you cast attachment flanges around the perimeter, and use spline couplings on the input and output ends of the crankshaft, you could stack these things at will to form 6, 9, 12 etc. cylinder motors. You could even stagger the angles to aid in the balance (which already should be very good); ie. for 2 modules, orient them at 60º to each other. One distributer with 12 terminals could be used, by just tapping however many of them you need. Throttle linking can be just as simple as the system used on a dual-quad or 6-pack setup.
  13. Aug 13, 2005 #12
    These "Radial" engines (as they were called at the time, because of the radial arrangement of their power strokes) were actually quite efficient and powerful. The inherent 'inertial' nature of the large rotating masses produces no problems for aircraft which control speed simply through prop feathering, and they were quite reliable. In addition, they had great cooling characteristics. The big drawback to these engines came from their large frontal areas, which produced drag and thus, for a given power, had their top speeds limited.

    Last edited by a moderator: May 2, 2017
  14. Aug 13, 2005 #13
    In this and and possibly follow-on entries, I'm going to try to make a few comments, but first I ask if there is a clearer, better annotated drawing, for example, what are the parts, and which is example number 1, example number 2, etc. Also the pistons should be numbered.

    The first observation: because of the geometry of this setup, it appears that the crankshaft will never be large enough to handle the power generated by the three cylinders, and thus it will have to always be run at reduced power. You might look at the possibility of more than three cylinders, in order to increase the working radius. I expect to send other comments if I can get a clearer picture.


    PS. There have been other similar radially configured rotary-piston Otto Cycle engine inventions in the past, in addition to the one shown in an earlier insertion of this string.
  15. Aug 13, 2005 #14
    To be clear, you are talking about the radial engines that are stationary. The early radial engines actually spun on its mount. So the propellor was actually rigidly fixed to the engine, and the whole unit turned as one. That set up DID have BIG inertial problems when the pilot turned the airplane.
  16. Aug 13, 2005 #15


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    I have not to be challenged by anyone. You are challenging the whole automobile industry, claiming these designs are "simply ignored". Ignored why? Because of a conspiration against you and the few people who believes such models are more reliable than the existing Otto and Diesel??.

    Any small modification in engines (i.e. stratified mixture) took 20-25 years to be since its publication in specialized issues, taken into account by automobile industries. This is because there have been MILLIONS of studies about what happens into a Diesel combustion chamber, and there have been ONE or TWO studies about what happens in a combustion chamber of one of the engines you posted or anybody knows in detail how the hell is the flow field inside them or how to choose the materials involved.

    So what nothing!. But the engine of our friend will be more disbalanced than those three ones.

    You are deviating awarely the main topic of this thread for only some hidden purposes of pursuing me, but you are not going to achieve it. :mad:
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  17. Aug 13, 2005 #16
    Let's see if I can understand. You can challenge others but can't be challenged back?

    If I challenged the whole automobile industry, I apologize! I simply stated that those like the inventor face stiff obstacles, even when they have engines that are up and working (I don't think this one has a working engine - - - and would suggest that he get one). They are still ignored! and that has nothing to do with me. They would be ignored if I didn't exist; that's obviously not a conspiracy against me. I don't believe in conspiracies. They take too much work.

    As far as reliability is concerned, some of those inventions are more reliable, than the Otto and Diesel cycles, and some are less reliable. That and a dollar will get the inventors a cup of coffee, but not much more. The simple fact is that the inventors face an uphill battle, no matter how good or how bad their inventions are. What I am begging you and others for, is to please not dismiss or belittle them beforehand. Give them a chance to prove themselves.

    It sometimes takes longer, but not necessarily because of the science; because of the NIH Factor. A perfect case at point, the overhead cam arrangement used by almost all of Today's engines. Duesenberg had it in the 1920s. Ferrari had it in the 1950s, most European and Japanese cars had it in the 1960s and 1970s. The American makers finally discovered it in the 1980s, not because they wanted to but because they had to. How many studies had the Duesenberg people conducted. All we know is that their engines beat the pants off everybody else with their well studied engines. Give the little man a break! Don't reject new ideas out of hand! Keep an open mind, most won't work, but with a little open mindedness, a few will work well.

    Actually, I suspect that their engines will encounter serious problems before it can be made to work. I just don't think that balance presents such a serious problem. The thermal/cooling problem that you mentioned earlier strikes me as much more serious. Also an even more serious problem that they face is that of port sealing. I don't see how they are going to achieve the compression ratios needed in an Otto/Diesel Cycle engine without a lot of development work and at great cost. Another problem is the one I brought up just earlier Today. Don't think I'm attacking you. I just ask that you cut the inventors a little slack. They'll need all they can get.

    I don't understand. What hidden purpose is this? Remember, you made a few very broad encompassing statements. I just called you on them. Don't get yourself into a huff over it; just back-up what you said. Remember, for instance that you said the following:

    This is just not true! Several of these engines have worked just fine. Others are still in development but that doesn't mean that they won't work. I'm asking that rather than knock these efforts, that you encourage them. Some will fall flat on their faces. Others will just be forgotten whether they work or not - - - just like the steam engines of the past (though some of those worked incredibly well). One or more of those though, with a little encouragement, might be just what the world needs. Give them a break! With regard to the idea initially proposed in this string, I remind you of the following:

    Before passing judgement, give them a chance to prove themselves. You state that the 'centrifugal turning' will be a problem. I cannot agree. There have been too many such engines with this characteristic that worked very well. I see no problem with this rotational characteristic itself, except that it will make the input and output ports difficult to seal (much like the Wankel). I am very sorry if you took it personally.

  18. Aug 14, 2005 #17
    You are, of course, right. No one wants to attempt to turn right or left and instead wind up nosing down. That tends to lead to a few unpleasant feelings (or cheap thrills). What we are saying though is that the problems of of inertial engine masses are inertial (precession, acceleration, etc.) and not particularly associated with the efficiency of the engine itself. Thanks for the clarification.

  19. Aug 14, 2005 #18


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    When a thread comes in this way, I have nothing to do in it. It would take a face-to face conversation with you to make you realise I have never diminished or belittle those engines before hand. We do know what industy is. We do know that if industry people have a thing that works at least infinitesimally better than another one new, they will remain using the older thing, specially in aeronautics and automobiles. I don't know if the word "reacious" exists in english. To sum up, they are too reacious of changing things. I said those models don't work properly merely because they are waiting at the background, not because they simply don't work. I am not an expert at them, but some worse advantages must have in order to be rejected by companies. They hadn't rejected wankel model by the way, they tried it and they have realised about its defects. Diesel and Otto engines have been broaded studied. Maybe in the future, when the studies will be extended to those secondary models, they will get the foreground of the industry, but today they don't work as properly as Otto and Diesel engine. It's a trivial statement.

    This is all what I am going to say about this stuff. I can seem very conserver for thinking so, but I only think logically and I don't believe in science fiction films. Anyway, I don't think this discussion benefites the OP, who will be staring at our dialogues with eyes wide open. Let's recover the main topic of the thread, please.

    I have not read all his post, nor I understood it well. Can anyone tell me where is the spark plug? Is it rotating or is it steady on the outer cage?. Thanks.

    Last edited: Aug 14, 2005
  20. Aug 14, 2005 #19


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    I have realised some problems about this design (sorry man, but if you have posted your invent here, our main mission is to bring you down to the floor :biggrin: ):

    i) the performance in exhaust and intake flow is very studied in traditional engines. I don't see how the combustion chamber can swallow air during the rotation. What kind of valves shape would you use?. When the combustion chamber is nearly to end the open angle for intake, the effective shape of the intake duct will be very strange, with a great loss of pressure due to it. I am not able to explain it better, but imagine just the moment when the intake valve is opened and the cylinder block wall approaches it. Also, it would be a complex flow induced by the rotation of the chamber. The nature of this initial flow have a GREAT impact on the combustion process. So a further study will be needed.

    ii) combustion process: despites the flow induced by the intake, the combustion process is going to be necessarily influentiated by rotation. Firstly it will be a great cummulation of gasoline near the spark plug, because it is a weighter component. This could be a good thing indeed. It is a great mechanism of producing an stratified mixture and avoiding the effects of flame failure near walls. But what affraid me most is the fact of the spark plug being attached to the outer casing. The plug needs a portion of mixture which initiates the premixed flame. In Otto-Diesel engines, the flame can advance with certain grade of spherical symmetry, but in this engine both burnt gases and flame will be influentiated by the rotation, and by means of the rotation inertia both flame and burnt gas will be prone to remain in the most rearward wall facing the spinning, enhancing the wasting of a great amount of fuel.
  21. Aug 14, 2005 #20
    Dont forget, Sir Frank Whittle had to practically BEG the british military to get funding to work on the jet engine during WWII, and even he was shot down a few times.

    "While often regarded as the father of modern jet propulsion systems, the young Frank Whittle tried without success to obtain official support for study and development of his ideas. He had to persist his research on his own initiative and received his first patent on turbojet propulsion in January 1930."

    Sadly, I agree with kennethman man. Even if his engine did work, I dont see it making much change, at least in the auto industry, unless it can provide benifits that are SIGNIFICANT in efficency. You gota remember, people are buying hummers that get 8mi/gal HIGHWAY, frankly, people in the auto industry really just DONT CARE. But I do think it could make it way to powering other devices, such as machines for factories etc. But then again, what company would want to pay retrain their technicians on how to service this new engine if it does not provide, ball park 20-30% efficiency. Its just cheaper to keep what does work and is the industry standard for so many years.

    The ONLY car to use a wankel is the nissan. Some aircraft use them, due to the low vibration. But still, go check out any small airplane, its engine is a STANDARD opposed 4 or 6 cylinder. These engines have more vibration than a wankel, but any pilot will tell you that they simply cant afford to replace the seals on the end of the wankel that go bad much faster than the seals on a piston. For a wankel, you have to practically rebuild the engine every time those seals go bad. My little honda has 100k+ miles on it with the same seals. Its a matter of how much money one is willing to spend for the small benifits of a particular engine. Most likely, his engine would have to be used on something highly specialized, not generalized.

    Oh, and as far as his picture goes, the only thing I see that could use changing is his pistons. Dont make them square, give them a radius of that circle, so on the compresson stroke, you dont have that wasted space. You can get a very high compresson, and possibly avoid the spark plug.
    Last edited: Aug 14, 2005
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