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endless screw reducer

  • Thread starter Thread starter ector
  • Start date Start date
the problem in my case would not exist because the relationship of red must be at least 100....
cmq interesting the topic, I have to deepen for benign. . .
 
But I do not agree that an endless screw reducer is always reversible. Recessed what is said as a hunter... Effectively never trust university professors!
However there will be a greater angle of the propeller than zero that will give irreversibility. In fact if I have a thrust force of the tooth on the propeller, I will always have a circumferential component (which turns the propeller) and an axial that (in addition to risking splitting everything) generates friction that brakes rotation.
the more you reduce the angle the more, at equal push, the circumferential component is reduced and the friction increases... it is easy to calculate the angle for which the forces are equal and therefore the system becomes irreversible. You think?
Since then, this also depends on the friction coefficient, perhaps it is possible to dimensionalize everything by getting out the performance. ..it would have to put the pen on paper, but at this time I have some difficulty in doing so.
 
However there will be a greater angle of the propeller than zero that will give irreversibility. In fact if I have a thrust force of the tooth on the propeller, I will always have a circumferential component (which turns the propeller) and an axial that (in addition to risking splitting everything) generates friction that brakes rotation.
I think you are perfectly right, in fact if you give an eye to the pages of the catalog bonfiglioli that I attached to the message #20, there are transmission reports for which v.s.f. are totally irreversible. Those two pages are very interesting, especially when they distinguish between static and dynamic irreversibility.
This doesn't take away that a self-frenating engine never hurts, especially not to be called by the customer who fell the elevator on his foot (you know, he had a particularly well-lubricating oil and a particularly well-made toothpick... :smile: ).
should distinguish: applications with vibrations and particularly delicate: We pretend that irreversible couples don't exist. the other applications instead, we check randomly!
 
When I was working in the field of "lifting", the endless screw gearboxes had to have a lower angle of four degrees (I'm sure they were three, but it seems to me that they were four) to be accepted by the then ispels.
that corner was the limit that guaranteed irreversibility.

In fact, it is true that there is always reversibility, but beyond a certain limit the torque to be applied to the slow shaft is so high to overcome the mechanical resistance of the reducer and therefore not applicable (because the reducer you calculated it safely, factor 10).

My memory, after my last birthday, was a little cloudy, but I was a kid, man! !
:smile:
 

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