Understanding Gear Ratios: Inputs vs Reality

  • Context: Automotive 
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    Gear Ratios Reality
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Discussion Overview

The discussion revolves around the concept of gear ratios and their practical implications in real-world applications. Participants explore how various parameters such as angular displacement, angular velocity, angular acceleration, and torque relate to gear ratios, particularly in the presence of factors like friction and backlash.

Discussion Character

  • Technical explanation
  • Debate/contested

Main Points Raised

  • One participant states that gear ratios relate to angular displacement, angular velocity, angular acceleration, and torque, but questions which of these will scale exactly to the gear ratio in reality due to factors like friction.
  • Another participant suggests that all variables are affected to some degree by backlash, strain, and friction, noting that strain and backlash are often ignored, while friction is less frequently disregarded.
  • A different viewpoint claims that the rpm typically matches the gear ratio in practice, asserting that gears do not slip.
  • One participant argues that all variables except torque scale exactly to gear ratios, indicating that input torque is greater than output torque due to friction.

Areas of Agreement / Disagreement

Participants express differing views on how various parameters scale with gear ratios in reality, particularly regarding the impact of friction and whether torque behaves differently from other variables. There is no consensus on which variables are affected and to what extent.

Contextual Notes

Participants acknowledge the influence of friction, backlash, and strain but do not fully resolve how these factors quantitatively affect each variable in relation to gear ratios.

Who May Find This Useful

This discussion may be useful for individuals interested in mechanical engineering, physics, or anyone looking to understand the practical implications of gear ratios in machinery.

961008
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The gear ratio is the ratio of angular displacement, angular velocity, angular acceleration, torque etc of the input with respect to output. However, I would like to know that which of these variables will be scaled exactly to the gear ratio in reality, as there might be some friction in the gear, or any other uncertainties in reality. So, which of these will be affected?
 
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All will be affected by some degree via backlash, strain and friction. In most cases strain and backlash are ignored so velocities and accelerations are proportional. Friction is much less often ignored.
 
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The ratio the usually matches "in reality" is the rpm. That's because gears don't slip.
 
All but the torque. Input torque will be greater than output torque due to friction. Angular displacement, angular velocity, angular acceleration all scale exactly to gear ratios.
 

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