alt.energy.renewable

"Tater" wrote in message
news: @ ...
> On Aug 30, 11:37 pm, clare at wrote:
>> On Thu, 30 Aug 2007 16:42:51 -0700, Tater wrote:
>> >On Aug 30, 10:32 am, gearhead wrote:
>> >> > Cars used to have permanenet magnet generators
>>
>> >> Which cars? Are you sure?>From what I know of antique vehicles with
>> >> dc generators -- series-
>>
>> >> wound, with segmented commutators -- they did not use magnets. I
>> >> speak from my experience with antique Harleys and GM trucks.
>> >> The only vehicles I know use magnets are motorcycles, and they use
>>
>> >your experience needs to be corrected. yes they had commutators,
>> >because the magnets were in the case, not the armature.
>>
>> >had some nice suckers in there, most autoshops pulled em out to use
>> >for welding magnets
>>
>> In north america virtually NO automotive DC generators had permanent
>> magnets Up untill only a few years ago, not even automotive STARTERS
>
> odd, I could have sworn that we would store screwdrivers and wrenches
> on the generators while working on cars. must have been magic pixie
> dust that let them stick
>

There was residual magnetism in the iron, but there was still a field
winding around the poles.

> also remember trying to pull them apart to clean commutators. the
> shafts seemed to have an unexplicable attraction to the blocks of
> metal on the motor casings, you know, where the feild coils would be
> in an alternator.

Field coils for *alternators* are on the rotor, not the casing. 'Field'
coils on the casing iron is proof that the field was an electromagnet and
not just a permanent magnet.

>
> you are talking about the north america on earth, right? fords,
> chevys, and such from the 60s and 70s? generators that were about 3
> times as long as delco alternators and maybe 2/3s the diameter?
>

Yep. Going as far back as the '20s, DC generators used field windings so
the output could be regulated. Same engines were also put in many small
boats such as Chris-Crafts and others.

daestrom