- #1

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So what is the radius in this case?

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- Thread starter Parsifal1
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- #1

- 61

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So what is the radius in this case?

- #2

berkeman

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Can you post a diagram to make this a bit clearer please? Also, is this for schoolwork?

So what is the radius in this case?

- #3

- 61

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Can you post a diagram to make this a bit clearer please? Also, is this for schoolwork?

Its a project. I don't know which type of gear I will be using yet, I just want to know what you would use for the radius in that formula in the case of a gear. Would you use the radius of gyration, using the outer and inner radius formula?

- #4

Nidum

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Gear motion calculations are based on pitch circle diameter - diameter D in your diagram

- #5

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So I couldn't use the formula s=r*angular displacement to work out the rotation of a rack and pinion gear?Gear motion calculations are based on pitch circle diameter - diameter D in your diagram

- #6

Nidum

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- #7

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Does that have formulas to work out displacement?

- #8

Nidum

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- #9

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So the linear displacement of the rack is equal to the linear displacement of the gear? If so I should be able to use the formula I mentioned?

- #10

Nidum

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or

Linear displacement of rack = ( angle turned by pinion / 360 ) x Pi x 2 x pitch circle radius .

- #11

Nidum

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- #12

Mech_Engineer

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- #13

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I see, so that was the formula I mentioned then. Problem solved.

- #14

Baluncore

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You do not need to measure the pitch circle radius. There is an easier way.So what is the radius in this case?

You only need to know the pitch of the linear gear rack and the number of teeth on the gear wheel.

That will give you the relationship between linear position and rotation angle.

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