Is this zero backlash or am I missing something?

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The discussion centers on whether a proposed gear system can achieve zero backlash. It is noted that a physical gap between the gears is necessary, which inherently leads to some backlash, especially during load reversals. Preloading gears with springs can mitigate backlash, but only up to the limit of the spring tension under load. Additionally, proper gear profiles are crucial to minimize mechanical noise and enhance performance. The effectiveness of the system may also depend on the application of constant torque, highlighting the importance of tooth profile in achieving desired results.
thorq
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Hello guys,

I am quite unsure if this application I have will be zero backlash using the solution in the attached image. I don't really have any means to test this so asking around sounds like a good feedback chance.
KSfVik.png

I haven't decided yet on the preloading solution but it will be done so that both driven gears will be pushing the motor gear as shown in the img. At this point, when motor stops and starts turning in the other direction, there should be zero time when any driven gear is not engaged by the motor gear's teeth. Or at least this is my theory.

Thanks for your feedback.
 
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Which flank of the tooth will be driving? Which flank of the tooth does each driven gear preload onto?

No it's not zero backlash because there is physically a gap (which needs to be there) between the gears, so if/when you get a load reversal the contact will separate.
 
Made a second drawing (actually this is more closely inline with my original idea):

mOkcVf.png

But then again, if the gap needs to be there (which is quite obvious), there will always be backlash unless split-gears preloaded against each other are employed...
 
Preloading the gears (springs) will always stop backlash unless the load exceeds the tension of the springs when erratic backlash will occur. Make sure your gear profiles are correct otherwise the mechanical noise (perturbations) involved in the mesh will greatly reduce any benefits of removing the backlash. Presumably, the system will not run at speed, unless you have some non-spring-based torquing of the system, like small motors, applying constant torque. If this is the case, tooth profile becomes the dominant property to address.
 
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