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Zero backlash worm gearing for pan and tilt

  1. Apr 19, 2015 #1
    I am designing a Pan and tilt drive for with stepper motor as prime mover. We need a zero backlash worm drive to transmit 70 Nm. motor torque is 1 Nm. What are the options.. position accuracy is 0.1 deg.

  2. jcsd
  3. Apr 20, 2015 #2

    Randy Beikmann

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    I am no expert on it, but I know people use "scissors gears," where one of the meshing gears is actually two gears with a spring preloading them to contact the front-and back-side of the other gear's teeth. I suppose the preload must be large enough to prevent either side coming out of contact during maneuvers. This will cause more friction, but that may also keep the pan/tilt support from moving once it's positioned.
  4. Apr 20, 2015 #3
    Thank you for response. I have come across split worm wheel concept while I was browsing. But what kind of Torque it can transmit (Given the PCD and no of starts). I could not figure out.
  5. Apr 22, 2015 #4


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    The two halves of the split worm wheel are preloaded by a spring or springs that generate a differential torque between the two halves. The strength of the spring determines the load that can be carried without hysteresis. If the spring is too strong then the worm and wheel will wear at a rate greater than necessary.
  6. Apr 22, 2015 #5
    Thank you. I should have been more specific. How to calculate the torque that can be transmitted. I want to transmit about 100 N.M in a particular application. What should be the Specification of the worm wheel and shaft?

    thank you .
  7. Apr 22, 2015 #6


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    Will you design and build your own worm and wheel, or buy from a catalogue?
  8. Apr 22, 2015 #7
    I want to buy from catalogue. But looking for zero back lash
    Thank you
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