Oddball non-boat Outboard question

Discussion in 'Outboards' started by Dieboat, Aug 19, 2016.

  1. Mr Efficiency
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    Mr Efficiency Senior Member

    Lots of hp applied to modestly sized gears.
     
  2. Dieboat
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    Dieboat Junior Member

    That is good information, thank you
     
  3. PAR
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    PAR Yacht Designer/Builder

    There are many (hundreds) of engineers and other professionals here, not just DIY'ers. We too think of odd stuff and try to make things work. Solving problems are the hallmarks of an engineer, NA and yacht designer.

    Given this, without a fairly good idea of the application, it's difficult to offer much. I do know you can get angle changers in various ratios. I'm not talk about ATV transaxles, but direction changers. In the boating world we often use V drives, which is little more than a direction changing unit placed in the shaft. Typically an aft mounted engine is mounted backwards, the trans bolted up and the shaft runs forward to the V drive unit, where its direction is changed, so it heads out of the bottom of the boat.

    Industrial applications for direction changing are well covered, including 1:1, which is fairly common.

    www.surpluscenter.com/Catalog/Catalog289-132.pdf

    Lastly, another hallmark of an engineer, NA or yacht designer is research and data. We literally have sources for just about everything or have a good idea where to look. Yeah, we're nut jobs . . .
     
  4. Barry
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    Barry Senior Member

    Dieboat

    A couple of things
    The gear sets that you are referring to are not ring and pinion but rather spiral bevel gears.
    You mention that you want a differential, but these require a ring and pinion, almost always a hypoid set up to allow differentiation with 2 or 4 pinions to allow two different axle speeds.
    The request from the contributors to have you explain more of what you are trying to do is really a request to understand what you are trying to do so their input can be more helpful to you.
    It appears, from the limited information that you are just trying to change the angle of shaft rotation by 90 degrees. If so, either a straight bevel gear set or a spiral bevel gear set is the way to go. A spiral bevel gives you less vibration than a straight cut spur tooth design.



    You had mentioned that you are thinking that you do not need an oil cooler. if you are considering hydraulic motors and pumps, cooling of the hydraulic oil has to be considered.
     
  5. Barry
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    Barry Senior Member

    One other point here as I re read some of your posts about attaching the ring gear to a differential carrier. You realize that if you are 1:1 ratio, the pinion gear that you refer to, would be the same size as the ring gear as you refer to????
     
  6. Dieboat
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    Dieboat Junior Member

    nut and honey

    Par,
    It was and is my sincere hope that you are at least partially, a nutjob, because only a nutjob would entertain my questions.:)

    Application, what will be a 4wd LJ20 (Think old school Polaris RZR).
    First step, to adapt diesel engine and hydraulic drivetrain creating operational 2wd.
    The engine placement remains the same as standard automobile; attached to engine is bellhousing and hydraulic pump, which is located in former transmission hump. Hydraulic pump hoses attach and fill large heavy hydraulic accumulator located behind front seat. Hoses from hydraulic accumulator power hydraulic motor. Hydraulic motor max continuous output 908 rpm, 172 ft. lbs. torque. Hydraulic motor connected directly to 3 position 4wd transfer case: 2wd, 4wd, and Lo 4wd. 2wd does not engage front driveline operates as 1:1. 4wd engages a splitter valve and both drivelines in 4wd 1:1, Lo 4wd engages both drivelines in 1.6:1.
    908 rpm with 30 in diameter wheels/tires in 2wd 1:1 is 81 mph i.e. plenty fast, but my math has not corrected for system inefficiencies, so fingers crossed for 70-75.
    I ran the numbers for the hydraulic motor connected to the transmission and had difficulty with engaging the 4wd, not to mention increased drag on the system.
    Looked at 4 individual wheel motors, but encountered cost issues as well as difficulty with shielding the motor/hoses from rocks, trees and/or road debris.
    The single wheel motor coupled to the transfer case was my compromise 2wd and 4wd (4wd low is getting into serious equipment destroying numbers)
    But, I need operational differentials i.e. spider gears, help you turn differentials.

    I replaced the differentials in my FJ40 a while back and after many learning attempts, got cozy with differentials. For a long time, I entertained two hydraulic motors, 1 front/1 rear in chain drive differential format. Planning the chain drive and fabrication of the differential carrier gear housing was not worry some, but fabrication of a chain drive or belt enclosure and converting from axles to A-arms so that the differential housing could remained fixed and able to utilize a chain drive was cost prohibitive. BUT my research into chain drive differential did provide many examples of how to attach a gear to a differential gear carrier.

    Currently, I have the LJ, the hydraulic components (minus a couple valves), so those pieces of the project have been sorted.

    Oh, the diesel engine will run at constant rpm until the accumulator is filled, then it will kick down to idle. The accumulator will absorb inconsistencies in vehicle power consumption, allowing engine to remain in efficient rpm band.

    This project is patterned, in part, after the car built by Ernie Parker in 1978 and Mr. Parker has been kind enough to provide input on my project. http://www.motherearthnews.com/green-transportation/hydraulic-drive-train-zmaz78mazjma.aspx
    Mr. Parker pulled 75 mpg from his hydraulic car in 1978, I will consider anything over a consistent 50 mpg, all gravy.

    There are far too many problems with the surplus city drives.

    I understand the pictures I posted thusfar are bevel gears, but I am sure I have run across a mercruiser gear setup with a pinion gear and a bevel gear with a large hole in the middle, very ring like.

    It’s late.
    Night all.
     
  7. Dieboat
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    Dieboat Junior Member

    Barry, I appreciate your input. Yes, same size, but mounted in an L. A 5x5 should fit inside the differential carrier and thusfar most found marine gears have been less than.
     
  8. Dieboat
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    Dieboat Junior Member

  9. Mr Efficiency
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    Mr Efficiency Senior Member

    How about indicating exactly what you are trying to do, it sounds likely to end in tears at the moment.
     
  10. Barry
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    Barry Senior Member

    You are correct. The difference in gear ratio can be determined by the number of teeth. Driving gear 25 teeth, driven gear 50 teeth, the gear ratio is 2:1

    The gear tooth must be the same size therefore if you want a 1:1, then the gears are the same size.

    On your example, you can just count the teeth on both gears to see that this is not 1:1
     
  11. Dieboat
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    Dieboat Junior Member

    Barry, Thank you for clearing my misunderstanding. I sit corrected. In this case, I was undone by the small print. The description of the part listing provides specifications on the gears as "25/25", under the picture is stated, "Photos shown are only a general representation of the product listing."
     
  12. Dieboat
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    Dieboat Junior Member

    Mr. E, I came seeking information. Currently my questions are: Theoretically, if a pair of spiral bevel, or bevel gears have 21 teeth and 19 teeth respectively, then if they turn together one direction the gear ratio is 1.105 (21/19) and if they turn together in the other the gear ratio is .904 (19/21)?

    I observe there is two large gears with a pinion gear in a boat gear set. Is this because the bevel gears should only be operated in a single direction?

    Finally, there are no tears, only fatigue. Battling status quo is the gamble of the hero or the idiot, hero if it works, idiot if it doesn't and the latter is more abundant.
     
  13. PAR
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    PAR Yacht Designer/Builder

    The odds are well in favor of the idiot side of the coin. No insult intended, just reality, as for every 100 ideas, 1 or 2 will seem good and worth pursuing. Of these few, maybe 1% will pan out and offer some hope, which are pretty lousy odds. Keep swimming little salmon, you'll get to spawn eventually . . .;)
     
  14. FMS
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    FMS Senior Member

    1 person likes this.

  15. Barry
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    Barry Senior Member

    The best way to look at it is input (driving) gear to output
    (driven) gear

    So the input gear remains the input driving gear whether or not it is rotating clockwise or counter clockwise. Hence the gear ratio does not change.
     
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