8 responses to “Wheels and Belts”

  1. Tobias Franke

    Could you add some explanation of why the belt goes to the highest point?
    I don’t understand it. And google or wikipedia are no help. And they call a totally different wheel-type crowned wheel.

    Thanks from an anti-mechanic ( All my recent projects can be summed up as removing the moving parts from some device.)

    1. Jacob

      The best explanation I’ve ever read of how a crowned pulley works was in the back of a magazine (Scientific American maybe?). It basically comes down to geometry; the crown of the wheel causes an off-center belt to wrap around it at an angle such the section of belt approaching the pulley is closer to the center than the section of the belt leaving the pulley. This causes it to drift towards the middle. It’s hard to explain without pictures though; this website (http://woodgears.ca/bandsaw/crowned_pulleys.html) gives an okay explanation, but not as detailed as the one in that old magazine. I hope I can find it.

      On an unrelated note, the Roomba example looks more to me like an O-ring belt than a timing belt.

    2. joshua

      this is a pretty awsome site but i have seen the magazine that jacob was talking about. if you want to know what kind of magazine its called just email gengjoshua@gmail.com

  2. Fluxor

    Great post Miss Outlier. Takes some of the mystic off the belt I see in my car. Not that I know how to fix anything in there, but as it’s de rigeur to open the hood when something goes wrong, I do it as well. Then I just stare.

  3. Paul Clarke

    As some know I work in the fan industry and we now have fans with direct drive. That is to say the motor is in the centre of the fan where as in times gone by people used a separate fan and motor connected via a belt drive.

    As a belt expert can you explain the issues with energy losses in using belts?