Calculating Radius of Driven Gear from Given Info

  • Thread starter Thread starter deuel18
  • Start date Start date
  • Tags Tags
    Gear Radius
Click For Summary

Discussion Overview

The discussion revolves around calculating the radius of a driven gear based on the rotational movement of a pinion gear and its specified diameter. The context includes design considerations for meshed gears, focusing on their angular travel and potential gear ratios.

Discussion Character

  • Technical explanation
  • Mathematical reasoning
  • Conceptual clarification

Main Points Raised

  • One participant describes the angular travel of the pinion gear at 85 degrees and the driven gear at 120 degrees, suggesting a relationship between their rotations.
  • Another participant proposes that if the pinion rotates at 85 rpm, the driven gear would rotate at 120 rpm, indicating a potential gear ratio that could be used to determine the driven gear's diameter.
  • A later reply notes the practical challenges of achieving the exact gear ratio with off-the-shelf parts and advises considering backlash in the design.

Areas of Agreement / Disagreement

Participants do not reach a consensus on the calculation method for the driven gear's radius, and multiple approaches are suggested without resolution.

Contextual Notes

The discussion does not clarify the assumptions regarding the relationship between gear rotations and does not resolve the mathematical steps needed to calculate the driven gear's radius.

deuel18
Messages
34
Reaction score
1
I'm currently designing two gears meshed together. I know that the pinion gear must travel at 85 degrees from 0 while the driven gear must travel at 120 degrees from 0 - both gears must travel and stop at the same time. In addition, I do know that the pinion gear must be 1 inche in diameter. Is there a way, based on the information given, to calculate the radius of the driven gear? Thank you very much.
 
Last edited:
Engineering news on Phys.org
So for every 85 degrees the pinion rotates the other gear rotates 120 degrees.
We could also say if the pinion rotates at 85 rpm the other rotates at 120 rpm, can you work out the gear ratio now? and use that ratio to find the driven gears diameter?
 
  • Like
Likes   Reactions: deuel18
I see. Thank you very much.
 
You're welcome, good luck.
It's reasonably unlikely you'll be able to achieve the exact ratio with OTS (off the shelf, as opposed to bespoke) parts so you may need to alter your design.
Also, keep backlash in mind:
https://en.wikipedia.org/wiki/Backlash_(engineering)
 

Similar threads

Replies
1
Views
2K
  • · Replies 2 ·
Replies
2
Views
3K
Replies
5
Views
2K
  • · Replies 2 ·
Replies
2
Views
5K
Replies
2
Views
5K
  • · Replies 3 ·
Replies
3
Views
4K
  • · Replies 17 ·
Replies
17
Views
4K
Replies
2
Views
3K
  • · Replies 6 ·
Replies
6
Views
3K
  • · Replies 3 ·
Replies
3
Views
2K