How does gear system amplify force?

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Discussion Overview

The discussion revolves around the mechanics of gear systems, specifically how they amplify torque and force. Participants explore the relationship between gear sizes, rotation speeds, and the resulting torque and force outputs in both theoretical and practical contexts.

Discussion Character

  • Exploratory
  • Technical explanation
  • Conceptual clarification
  • Debate/contested

Main Points Raised

  • Some participants propose that when a small spur gear drives a larger gear, the larger gear turns slower, which may imply that the torque transferred to the output is greater.
  • There is a suggestion that when connecting the output gear to a rope for lifting, the torque must be converted by dividing the radius.
  • One participant questions whether the output gear can produce torque of 2rf when the input gear has radius r and the output gear has radius 2r, suggesting that the gear system amplifies torque rather than force.
  • Another participant argues that if force is applied on the outside of the first gear and the second gear applies force from its outside, the force is not increased, emphasizing the need for the output speed to be slower than the input speed to achieve a leverage effect.
  • It is noted that gear systems are typically used to either increase torque and decrease angular velocity or decrease torque and increase angular velocity.

Areas of Agreement / Disagreement

Participants express differing views on whether gear systems amplify force or torque, with some suggesting that torque amplification is the primary function, while others discuss the conditions under which force may or may not be amplified. The discussion remains unresolved regarding the exact nature of force amplification in gear systems.

Contextual Notes

Participants have not fully resolved the implications of torque versus force amplification, and there are assumptions about the definitions of torque and force that may influence their arguments. The discussion also reflects varying interpretations of how gear ratios affect mechanical advantage.

Who May Find This Useful

This discussion may be useful for individuals interested in mechanical engineering, physics, or anyone studying the principles of gear systems and their applications in machinery.

null void
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If i have a small spur gear, and i rotate it and transfer the rotation to another gear with bigger pitch diameter. The output gear(bigger gear) will turn slower right? then does this mean the torque force transferred to the output is greater?

So when the output gear is connected to a rope to pull something up, i have to convert the torque force to by dividing the radius?
 
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The output gear(bigger gear) will turn slower right? then does this mean the torque force transferred to the output is greater?
Right
So when the output gear is connected to a rope to pull something up, i have to convert the torque force to by dividing the radius?
Right
 
Here is the real question, if i have a input gear with radius r, and output radius of 2r, when i apply force, f on input gear, the output gear can produce torque force of 2rf ?

when converting the torque force into force, i get f back as the output?

Does this mean the gear can't amplify "force"but they can amplify "torque force"?
 
null void said:
Here is the real question, if i have a input gear with radius r, and output radius of 2r, when i apply force, f on input gear, the output gear can produce torque force of 2rf ?
If you're applying the force on the outside of the first gear, and the second gear is applying a force from it's outside, then the force is not increased. Imagine a chain wrapped particlely around the two gears and that you're pulling on the chain. The chain's speed is the same everywhere. In order to get a leverage like effect where the force is increased, then the "output" speed needs to be slower than the "input" speed. There are various ways to do this.

A gear system is normally used to increase torque and decrease angular velocity. or to decrease torque and increase angular velocity.
 
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