Announcement

Collapse
No announcement yet.

Dc motor question

Collapse
X
 
  • Filter
  • Time
  • Show
Clear All
new posts

  • J Tiers
    replied
    Originally posted by Evan View Post
    The really interesting thing about that saying is that is about the number of binary bits it takes to represent either one.
    An interesting commentary then about the actual "information content"...... about equal, if I understand the reference correctly. Strange how the folks who made up those old sayings may have been smarter than it seems.

    Leave a comment:


  • Evan
    replied
    There is a reason why a picture is worth a thousand words.
    The really interesting thing about that saying is that is about the number of binary bits it takes to represent either one.

    Leave a comment:


  • Evan
    replied
    Using 24 volts ac for that motor also makes the product very easy to sell internationally, especially the US and Canada. By doing it that way all they need to do is change the position of a couple of wires inside for it to run on 117vac. The heaters would be two 117 vac elements in series or in parallel depending on line voltage and the transformer would be series or parallel primaries. The transformer is needed anyway to run the solenoids.

    Leave a comment:


  • J Tiers
    replied
    In HINDSIGHT, with all the posts visible, it is much easier to see how the description fits the actual device..... But, as can be seen from the various posts, a number of people got different mental pictures of the motor, from the "word picture" given.

    It is often very easy to answer the question when you already have seen the answer. Just as it is easy to see the answer to the "brain buster" puzzles in the newspaper once you get the next day's edition,.... then you see how obvious it was.

    Originally posted by Black Forest View Post
    Mr. Tiers, you seem to have a problem! Maybe the thread was worthless to you but not to me. As to the thread not being up to your standards, well tough sh!t! I guess we should all send you PM's with our posts to make sure they qualify and meet your criteria as to worth-fullness! Or at least I should as I am seemingly an idiot and not capable of expressing myself properly.
    Not at all... You are taking an offense which is not there to be taken. A magician you must be

    You don't know much about electric motors.

    I don't know much about sheep.

    You don't know what the important parts to describe about a motor are, to determine what it is. Consequently you are not able to give a good description, and a picture is desperately wanted to make what is a guessing game, into an easy identification. It is no reflection on you, it is just that nobody can know everything.

    I would be no better, and maybe worse if I were describing the illness or other problem of a sheep, and you might be saying bad words about that and wishing also for a picture which would make everything perfectly clear to you.

    In each case, the person, you, or me, would be very much better advised to take a picture and SHOW the thing which is in question. So many times it is NOT what is SAID that is the problem, but rather what is NOT said...... With a picture, it is possible to look at everything that is in the picture, and maybe see an important detail that a person who is not familiar with the subject could easily miss.

    This is not about you, it is inherent in a person trying to make words describe a thing without having the knowledge to be able to correctly identify the important features of the thing described.

    There is a reason why a picture is worth a thousand words.

    Leave a comment:


  • CCWKen
    replied
    I have a small squirrel cage fan on my coffee machine. It is 24v DC. It consists of a coil that is connected to a bunch of thin plates all stuck together. There is a hole in the middle that the armature goes through. There are no brushes.
    I was able to deduce from that description that it was more than likely the type I pictured. Let's get beyond that now that we know the type.

    What's still up in the air is the voltage but perhaps a cleaning and oiling will fix the problem. As already mentioned, these usually have oilite bearings. They dry out and get dirty and gummy. I haven't much luck trying to clean and re-oil those types of bearings. I think when they start to dry out, they smear the inner surface and close off the pores. Seems they still drag down after a short period. You can try to clean the other bearing but a motor replacement would be a sure fire way to get back to making coffee.
    Last edited by CCWKen; 12-03-2012, 09:11 PM.

    Leave a comment:


  • Evan
    replied
    Armature windings are mentioned in the original post. "The armature looks like it has windings on it also." It may well have copper conduction bars on the rotor, especially considering that it seems to run on 24 vac.

    Leave a comment:


  • becksmachine
    replied
    Originally posted by J Tiers View Post
    Now that BF has agreed the motor is something which is COMPLETELY DIFFERENT FROM THE DESCRIPTION.........
    Rotor windings were mentioned,
    As a point of curiosity, could you point out where BF first mentions anything about rotor windings?

    It seems a classic case of someone saying something that could be possible and then someone else taking it as the absolute truth.

    In hindsight, the OP description matches the CCWKEN photo very closely, given the DC description is probably wrong.

    Just sayin.

    Dave

    Leave a comment:


  • Black Forest
    replied
    Mr. Tiers, you seem to have a problem! Maybe the thread was worthless to you but not to me. As to the thread not being up to your standards, well tough sh!t! I guess we should all send you PM's with our posts to make sure they qualify and meet your criteria as to worth-fullness! Or at least I should as I am seemingly an idiot and not capable of expressing myself properly.

    Leave a comment:


  • J Tiers
    replied
    Now that BF has agreed the motor is something which is COMPLETELY DIFFERENT FROM THE DESCRIPTION.........

    Originally posted by Evan View Post
    Not very likely. Why would a brushless motor have windings on the armature connected to nothing? It's an induction motor.
    The description, was , frankly, almost non-understandable, it could have been either. BLDC, or some form of induction motor. BLDC are actually CHEAPER than induction these days, and way cheaper than brush motors, which is the other type which has rotor windings.

    Rotor windings were mentioned, but it isn't clear that such a description is more applicable to a squirrel cage motor than any other type...... the "windings" are a cast in feature.

    I did not trust any part of the description since it is somewhat self-contradictory, just as the descriptions are for many or even MOST similar internet questions. One picture of any quality would settle the matter without this sort of asinine bickering

    THIS THREAD WAS WORTHLESS WITHOUT A PICTURE

    The reply from BF shows the absolute worthlessness of the thread and all the guessing...... I KNOW BF had a camera, and they are not expensive, even if the SIL still has the first one.
    Last edited by J Tiers; 12-03-2012, 09:29 AM.

    Leave a comment:


  • EVguru
    replied
    It will be the bearings. They're just oilite sleeves and often haven't really been well impregnated in the first place.

    Leave a comment:


  • Black Forest
    replied
    The picture CCWKen posted is nearly identical to the one I have. Mine has no printing on the coil though.

    Leave a comment:


  • Evan
    replied
    Might easily be a DC motor, driven by what amounts to a tiny inverter...
    Not very likely. Why would a brushless motor have windings on the armature connected to nothing? It's an induction motor.

    Leave a comment:


  • CCWKen
    replied
    It sounds like a common shaded pole AC motor. What's not common is the voltage.
    What's the coffee maker brand and model number? It may be easier to go from that angle. If it's UL listed, there should be a diagram inside somewhere.

    Most will look like this:

    Leave a comment:


  • J Tiers
    replied
    Essentially THIS THREAD IS WORTHLESS WITH NO PICTURE

    Might easily be a DC motor, driven by what amounts to a tiny inverter...... many millions of small cheap computer cooling type fans are made that way. See if there is any little circuit board associated, it only takes one IC and a sensor or two to run it.

    if you cannot provide a picture, then at least determine if the 24V is supplied to it as AC or DC.

    Regardless, if it is running, odds are that the other bearing gave out, and replacing it will likely do the trick.

    Leave a comment:


  • darryl
    replied
    What you're describing is an ac motor. They can be wound to run on any voltage, so it's not surprising that it's a 24 volt motor, probably done for safety reasons as suggested. By far the most common failure mode is the bushings seizing up. If one goes bad, it's almost a certainty that the other will be bad as well. In many cases, you can oil them and all will be fine for a year or two, but often enough you have to get all the old oil residue out so it doesn't turn the fresh oil into goo and seize it up again. There's also often some kind of felt washer in there which is supposed to hold oil, and it's often sealed in by swaging part of the bearing retainer. A metal working enthusiast would probably get rid of both bushings and put in ball bearings.

    Leave a comment:

Working...
X