Author Topic: Fly weight governer on 20 foot machine (Read 23321 times)

Menelaos · « **Reply #33 on:** February 29, 2012, 09:29:57 PM »

uff...I already have more than 100 posts here, cant remember where it was...at the moment I am abroad and can only access via my galaxy note which is comfortable for writing but I do not have all my data here...I can post some pictures when I am back to germany and have acess to my PC...

Max

Royalwdg · « **Reply #34 on:** February 29, 2012, 09:30:44 PM »

Max, That sounds very good. We all have to keep in mind that if the world goes dark with power outages we will be building our stuff out of scoungable materials. Keeping it simple will be what it's all about. Dave M.

kensue49 · « **Reply #35 on:** February 29, 2012, 09:35:12 PM »

Thanks Max.
I have about 58 more to go through.
Kenneth

NoSmoke · « **Reply #36 on:** February 29, 2012, 09:36:34 PM »

Dave, a very nice piece of work! I have a similar pitch control turbine (uses pillow blocks and flyweights on the blade shafts but has torsion springs (on the shafts) and a somewhat different spider that doesn't require swivel joints). There's another thread here BTW that discusses the use of bevel gears for a "spider" that also looks interesting.

I gather yours rotates the blades to feather - I rotate mine to stall as it requires a smaller degree of rotation but it seems to work well.

One specific problem I had was coming up with a torsion spring of the correct value. What I turned out using were what look like large safety pins (I forget what they are called). The "coil"end of the pins was removed and installed on the blade shafts but they are only about 1 1/2 turns and I have had problems with the metal yielding from being rotated a little too far. What's needed I think is a 2 or 3 turn coil but I have not been able to find anything, at least in the right torque range. Using torsion springs on the shafts has the advantage BTW of removing their return force from the spider mechanism.

Re other's comments here, I have had no issues so far with thrust on the pillow blocks (1" blade shaft for a 13' rotor in my case) and also use pillow blocks (1 1/2") for the main shaft with the thrust being applied to the rear pillow block. They will successfully handle a certain degree of thrust so I guess it's mainly a matter of selecting something large enough.

I also admire your enclosure of the pitch mechanism. I tried to concoct something but it turned out clunky and did not seal at the shafts very well so I just left it off and sprayed everything thoroughly with roller chain lube. It has held up well to the elements for about a year now.

All in all I'm much happier with pitch control than with conventional "furling". I especially like the ability to control rotor speed even with no load and the fact it keeps going at pretty much at top speed even in strong winds.

Menelaos · « **Reply #37 on:** February 29, 2012, 09:39:25 PM »

ah...found it as well in the post some time back...here we go...

Ok, it does not really show the thing with the threades rod but thats what I have for now...

This picture is from about 2 years ago. That turbine has been running for 25 years now and still is in service...

windy · « **Reply #38 on:** February 29, 2012, 09:41:16 PM »

Royalwdg,

Nice looking machine.

I am building a similar type machine but without a tail. It will be a downwind generator.
As far as those bearings, I used the same bearing, but what I did was put a bushing over the shaft between the bearings. That way all of the load is pulling on both bearings instead of just the inner one.
I'll have to post pictures when I get it totally assembled.

windy

Menelaos · « **Reply #39 on:** February 29, 2012, 09:43:32 PM »

that actually is not a verry good way of doing it. One bearing should always be loose to adjust for extension due to temperature. If both bearings are fixed to the shaft there might occur tension forces that will not do any good...

kensue49 · « **Reply #40 on:** February 29, 2012, 09:48:38 PM »

Max
Is the pivot point of the blade the all-thread rod?
Is there a nut welded to a plate that acts as the bearing?
Kenneth

Menelaos · « **Reply #41 on:** February 29, 2012, 09:56:13 PM »

yes, thats right, there is a long nut that serves as the bearing. In 25 years aou can hardly see any wear of the thread...

There is only one problem with this kind of bearing, it gets hard to turn of there is a lot of wind power pushing the blades back towards the tail, but there is a solution for this. The blades ares slightly tipped back towards the tower. In this case it is 2 degrees. As the centrifugal forces of the with increasing wind speed tend to "tighten the blades and move them forward, there is a point where there is hardly any friction in the "bearing". That point of equal forces between the wind pushing the blades back wards and the centrifugal forces pushing them forwards is the about the RPM when the pitch mechanism starts to act.
This way there is basically hardly any friction to the bearing when the blades pitch...

Really clever actually! Its not made by me but by my previous employer, that guy is great :-)

kensue49 · « **Reply #42 on:** February 29, 2012, 10:15:54 PM »

Thanks, that makes sence.
Is the material brass, steel ,zinc coated steel or SS?
Kenneth

Menelaos · « **Reply #43 on:** February 29, 2012, 10:17:16 PM »

Stainless steel

kensue49 · « **Reply #44 on:** February 29, 2012, 10:43:46 PM »

304 or 316?

midwoud1 · « **Reply #45 on:** March 01, 2012, 04:49:48 AM »

On the rotorblade shafts I use angular-contact bearings ( the inner) to handle centrifugal force.
The outer are sealed deepgroove ,protected against weather.
I don't believe they will be hammered out ( its locked with retainers and a drop of loctite )
Loctite medium duty. Thats possible to to take it apart later.
On the mainshaft tapered roller bearings will do good .
I haven't yet because of small prop diameter.
The system works very nice.
Interesting Max mentioned about Tiger and Panter tanks transportation to Russia in WW2.

- Frans -

Menelaos · « **Reply #46 on:** March 01, 2012, 07:41:13 AM »

Hello Frans,

That example with those tanks I was told by my previous employer who has 30 years of experience with pitch controlls. He had many bearings hammered out or the grease would come out of the bearings due to centrifugal forces after some time. Probably not after a month, maybe not after a year...but at some point. You live in Holland and might even know that guy, Constant Seiwerath... He was the first guy who built and installed a grid connecteded wind turbine in Luxembourg. That think in those days 30 years back had 20 KW :-)

Anyway. For my next pitch turbine I will again use this for the bearings:

http://www.mercateo.com/p/live~showGrossColumn*183-64004000/Trapezgewindespindel_DIN103_Tr_40_x_7_x_1000mm_lang_eingaengig_rechts_Material_C15_gerollt.html

except that I make them myself out of SS and do not buy them...

Max

PS. I live near Bremen which is not that far away from the dutch border, If you are located not too far from the border, I would really like to come by and have a look at your turbine and pitch assemblys...of course only if thats finde for you ;-)

midwoud1 · « **Reply #47 on:** March 01, 2012, 10:51:12 AM »

Hi Max.

You are welcome . Distance 314 km.

windmill3@hetnet.nl

- Frans -

kitestrings · « **Reply #48 on:** March 01, 2012, 04:40:07 PM »

Dave,

I came to this one a bit late, but just like to similarly commend you on a great looking build, and interesting post. Lots of work summaraized in just a few pixals. Thanks for sharing it.

It looks as though they (the blades) all rotate in unison, so independent of an individual spring failure you still in good shape. It is all very, very nice.

Quote

I tend to overbuild. A little.

Well, IMO that has to be part of the arsenal to combat Murphy. Someone early in the post mentioned a Dunlite unit. I worked on a few with Neilho years back. Always thought it was a pretty good design in concept. The gearbox, alternator & fly-ball governor was huge and well overbuilt one could say for a 2 kW machine. But, as I recall they skimped in a couple key points, like blades, which suffered from fatigue, the tail connection which regularly broken (and frequently accellerated the failure date of the blades).

Thanks too, to Max for contributions. A similar theme for you and midwoud, huh?

Best of luck, and do update as/when you can. Kind regards,

~kitestrings

cdog · « **Reply #49 on:** March 12, 2012, 09:42:24 PM »

Do you mind saying what the blades cost....and do they offer larger than a20' set?

hvirtane · « **Reply #50 on:** March 13, 2012, 04:25:55 AM »

This seems to be really good. Thank you for sharing pictures of the design. I think you cannot make it with much less parts.

-hv

fabricator · « **Reply #51 on:** March 13, 2012, 07:54:39 PM »

Quote from: cdog on March 12, 2012, 09:42:24 PM

Do you mind saying what the blades cost....and do they offer larger than a20' set?

Dave builds and sells the blades. http://www.royalwindandsolar.com

cdog · « **Reply #52 on:** March 13, 2012, 08:26:27 PM »

Thanks but i didnt see pricing on anything over 10' on the site??

cdog · « **Reply #53 on:** March 13, 2012, 08:30:20 PM »

Unless the pricing is for a single 10' blade?

fabricator · « **Reply #54 on:** March 13, 2012, 08:38:05 PM »

No they come in three blade sets, you would have to contact Dave about the longer blades.

cdog · « **Reply #55 on:** March 13, 2012, 08:42:37 PM »

So if i understand correctly a 10' set is 175 bux?

fabricator · « **Reply #56 on:** March 13, 2012, 09:21:44 PM »

nekit · « **Reply #57 on:** March 13, 2012, 09:53:10 PM »

I have a set of these. They are $175 ea for 10' blade, 20' dia turbine.

cdog · « **Reply #58 on:** March 13, 2012, 10:01:46 PM »

Cant beat that....has he been known to maker larger?

NoSmoke · « **Reply #59 on:** March 14, 2012, 12:13:12 AM »

I find the web site ambiguous as to pricing. In all instances it refers to "blade", not "blades" (except for the "Complete 4-Blade Wincharger Package") eg. a "10 foot custom wood turbine blade" is $175. This does not appear to apply to a "set" especially as the number of blades in a "set" is not given (except for the 4 blade Wincharger package).

It's not even clear, to me at least, if the dimension refers to the blade length or the resulting rotor diameter.

I'm gathering then that a set of blades for a three blade 20 foot rotor would cost $175 x 3 = $525.

I note they are also apparently constant profile and pitch (which is a bit off-putting IMO).

cdog · « **Reply #60 on:** March 14, 2012, 08:33:30 AM »

Exactly why i was confused....i feel better now !!!!

fabricator · « **Reply #61 on:** March 14, 2012, 11:04:54 AM »

Well contact Dave, that's the simple answer, and as for constant profile and pitch, these blades are torque monsters, if you put em on a turbine you better have a good way to shut it down, or dump a lot of power, the Dans put a set on one of their 17 foot machines and they smoked it.

cdog · « **Reply #62 on:** March 14, 2012, 11:18:24 AM »

Sounds like a good blade for gearing up?
This is why they have caught my eye.....id like to have 25' diameter though....

NoSmoke · « **Reply #63 on:** March 14, 2012, 12:25:10 PM »

Quote from: fabricator on March 14, 2012, 11:04:54 AM

Well contact Dave, that's the simple answer, and as for constant profile and pitch, these blades are torque monsters, if you put em on a turbine you better have a good way to shut it down, or dump a lot of power, the Dans put a set on one of their 17 foot machines and they smoked it.

Would not argue with the torque characteristic but I question if that`s they way to get best performance from a given blade size as power output is the product of torque and RPMs. These `torque monsters` don`t tend to turn very fast so the torque & RPM product tends to be smaller than for a more aerodynamic, faster rotating blade i.e. one with varying pitch and profile.

Higher RPMs also allow for a physically smaller alternator or, less need for a gear-up. I guess though advantages of constant pitch and profile would include some measure of self-RPM limiting (as the blades operate somewhat in drag mode) and maybe cheaper to manufacture (no compound curves). Also easier to brake I suspect.

Royalwdg · « **Reply #64 on:** March 14, 2012, 02:20:45 PM »

Fabricator, I've been out of the office for a few days so I'll have to get caught up. Since the forum changed I wasn't able to sign back in and following the instructions if I had trouble did not get me results. So I started again as a newbie so when I added my webite to my profile it was removed. So thank you for mentioning that. Anyone can contact me through my website about blades and new developments on governors. I appreciate this forum and don't want to promote my stuff here. I just brought down my turbine for adjustments to the gov and anexperimental change. I have been pitching the blades forward to furl and now I will change the weight arms around to make it feather to stall (leading edge back, trailing edge forward. As I mentioned before about the lift vector leaning toward the direction of travel, it will now go to a backward angle with tail scooping wind. Should be a quieter furling and actually slow it to my previous expectations. Dave Moller

fabricator · « **Reply #65 on:** March 14, 2012, 02:59:34 PM »

Quote from: cdog on March 14, 2012, 11:18:24 AM

Sounds like a good blade for gearing up?
This is why they have caught my eye.....id like to have 25' diameter though....

Yes they are, a 12 foot geared turbine will likely out perform a 25 foot direct drive by quite a bit and be a lot less headache as far as support structure goes, just check what Chris Olson is doing.
He has 10 foot machines that out perform his Jacobs.

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Author Topic: Fly weight governer on 20 foot machine (Read 23321 times)