Question about the theory of machines

Thread starter dorteam
Start date Jun 22, 2020
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Engineering Machines Physics Theory

AI Thread Summary

The discussion centers on a misunderstanding regarding the angle turned by a crank in relation to the inner dead center, with a participant questioning the accuracy of the stated 2400 degrees. Clarification is suggested, proposing that the correct angle might be 240 degrees instead. The concept of dead center in engineering is referenced for further understanding. The conversation emphasizes the importance of precise terminology in mechanical discussions. Accurate measurements are crucial for effective communication in engineering contexts.

Jun 22, 2020

dorteam

New poster has been reminded to show the Relevant Equations and their work on the solution

Homework Statement: The stroke of an internal combustion engine is 180 mm. The connecting rod is 3 times the crank length and has a mass of 40 kg. The mass of the reciprocating part is 12 kg. The centre of mass of connecting rod is 110 mm from the crank pin centre and the radius of gyration about an axis through the centre of mass is 148 mm. the engine runs at 320 rpm. Find the magnitude and the direction of the inertia force and the corresponding torque on the crank shaft when the angle turned by the crank is 2400 from the inner dead centre.

Relevant Equations: They're in the given question.

I couldn't do it

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Jun 22, 2020

Lnewqban

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dorteam said:

... when the angle turned by the crank is 2400 from the inner dead centre.

Welcome!

I believe that data is not correct.
Perhaps 240 degrees?
Either top or bottom dead center.

Please, see:
https://en.wikipedia.org/wiki/Dead_centre_(engineering)

Jun 22, 2020

haruspex

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Lnewqban said:

Perhaps 240 degrees?

... with the typography being 240°.

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