Kiekhaefer Awarded Patent On New Variable Propeller Pitch Surface Drive
01-15-2018 | 01:43 PM
#11
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From: Jersey Shore
.
engineers always win the race!
curious when they will make this available for outboards
Would love to see the schematics of the internals, it's patented so should be safe to show
,
engineers always win the race!
curious when they will make this available for outboards
Would love to see the schematics of the internals, it's patented so should be safe to show
,
Last edited by noli; 01-15-2018 at 02:35 PM.
01-15-2018 | 01:43 PM
#12
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From: Ft. Worth TX
https://www.youtube.com/watch?v=C5niXCY-ikM
land & Sea - yes the company whom makes dyno's and use to sell the sternjack
land & Sea - yes the company whom makes dyno's and use to sell the sternjack
Last edited by BUP; 01-15-2018 at 04:13 PM.
01-15-2018 | 02:27 PM
#13
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From: Ft. Worth TX
01-15-2018 | 02:28 PM
#14
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From: Ft. Worth TX
Hopefully shows
01-15-2018 | 04:04 PM
#15
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After his career, retiring from Mercury Racing obviously didn't mean a coffee on the porch rocking the day away... Good to see his talent, innovation and offerings to the marine enthusiast didn't stop at the office party. The man is brilliant in his own right
01-15-2018 | 04:13 PM
#16
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From: Cleveland, OH / Pewaukee, WI
the basic idea was in the market place from the 1990's for the mechanical versions called shifting props. They used the marketing words as comparing to transmission but the prop shifts ( changes it pitch )
Land & Sea, also Aero Star and Merc had their versions way back then. I still have the Aero Star version. These were mainly marketed to the Rec boat user way back then..
Land & Sea, also Aero Star and Merc had their versions way back then. I still have the Aero Star version. These were mainly marketed to the Rec boat user way back then..
01-15-2018 | 04:57 PM
#17
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For some reasons youtube links are not showing but here is another link to what was made before by otheres.
Drive manufacturer Yellowfin goes into administration - Motor Boat & Yachting
Drive manufacturer Yellowfin goes into administration - Motor Boat & Yachting
01-16-2018 | 06:29 AM
#19
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Understand variable pitch by aircraft screws. There you have bigg forgiving factor at diferent angle of atack arround the inside half diameter. Air screws work good also by airfoils with ticknes more than 20% in inside 1/3 diameter...
But water is hard and you have no chances for good efficiency with bigger angle of atack. Hydrofoil of prop blade is always wery, wery thin (Specially labed...), it mean no forgiving of wrong angle of atack:
- props must be really good matched for example for 30" pitch.
- if you change pitch for more than 2", you totaly destroy geometry of blade and by by efficiency.
- by variable pitch you change pitch all the time, it mean:
a.) You are almost always out of best matched angles of blade segments, somewhere you have to bigg, somewhere perhaps negative angle of atack.
b.) You need "universal" blade geometry, which have "good" caracteristics all around from min to max pitch, but in optimum regime will be worse than good fix propeller. Probably worse than fix aluminium propeller.
Variable blade is probably super solution for slow boats and ships, but probably no go with fast boats.
Prop blade by surfacing prop you could compare with fighter wing at supersonic speed. Did they change airfoil configuration (elerons, flaps, spoilers, swept of wing...)by supersonic flight? NO!
But water is hard and you have no chances for good efficiency with bigger angle of atack. Hydrofoil of prop blade is always wery, wery thin (Specially labed...), it mean no forgiving of wrong angle of atack:
- props must be really good matched for example for 30" pitch.
- if you change pitch for more than 2", you totaly destroy geometry of blade and by by efficiency.
- by variable pitch you change pitch all the time, it mean:
a.) You are almost always out of best matched angles of blade segments, somewhere you have to bigg, somewhere perhaps negative angle of atack.
b.) You need "universal" blade geometry, which have "good" caracteristics all around from min to max pitch, but in optimum regime will be worse than good fix propeller. Probably worse than fix aluminium propeller.
Variable blade is probably super solution for slow boats and ships, but probably no go with fast boats.
Prop blade by surfacing prop you could compare with fighter wing at supersonic speed. Did they change airfoil configuration (elerons, flaps, spoilers, swept of wing...)by supersonic flight? NO!
Last edited by plavutka; 01-16-2018 at 08:27 AM.
01-16-2018 | 09:00 AM
#20
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From: Collierville, TN and Pickwick Lake
And the man cuts his own grass. Ask me how I know.
