"coclee" of forum 2010

[LuiVerde]

I participated in the forum 2010 in modena and saw how they "resolved" the representation of some types of screws without using the spiral in skizzo 3d .
Having recently faced a similar problem for a rototranslating cochlea (I have not managed to get over it) I try to involve the forum to find out if any of you have already arrived at the solution.
problem : I have to build a cochlear with 4 linear steps the first 2 the step is 86.5 the third is173 the fourth 86.5, this to move a jar ø 85 (premix that you can build well with a cnc machining).
My bran is : you can model such a cochlea in inventor 2k11 faithfully.
I attach 2 images to make it clear and the 2 ipts; the coclea 1 is made with the method described in the forum and is the most faithful (but with the problem that in step 173 the jar is in collision with the 2 sides of the trapezoidal profile), while the second was made with a sweep subtraction created with an envelope line around my cylinder.
(I have read the previous discussions but none of the discussions I have read has been decisive in my opinion )

Sorry I wasn't very clear. Hi.

 

[diegus]

the suggested methods to the forum still have not tested them (they look interesting) but if I need propellers with variable step use this method:
in a 3d sketch I create many helical curves one behind the other with the step and the revolutions I need. I use the constraints to bind the axis of each helid and then bind the ends of the curves between them.

place files as an example

 

[LuiVerde]

just diegus but...
I have always done them as you say with the helid, but in the specific case where the coclea has to move a cylindrical body that must remain perpendicular to the axis) , the profile (which you see from the view from the top ) that advances the jar must be constant . if you see from the images attached the ø of the jar hung on the sides of the pitch + long because radially it is + small.
in the cnc processing the tool of ø 85( perpendicular to the axis of the axis of the axis of the axis of the axis while it turns with the ratio 1 turn > 86.5 mm step and 1 turn > 173 mm step this determines that the resulting location (view in plant ) is constant . I hope to be explained

 

[Tarkus]

This discussion was born a few years ago from a post, it seems like vigz, and there was also evidence of the non-fidelity of a sweeping profile.
Anyway, I think your problem is that you can't replicate what happens in reality with the cnc.
in fact inventor makes you an elliptical excavation; But then, (I didn't try and maybe say a caxxata) why not use an ellipse instead of the circle... how to do this ellipse? Maybe projecting on a plane the excavation that sweeps, measures in what percentage you "stringe" the circle, and act accordingly opposite on the sketch of the sweep profile...

 

[Tarkus]

It's not even an ellipse but a more complex figure, so it would be difficult to create an exact ad hoc profile.
rather two questions:
- the tool you use is a cylindrical cutter of ø 85 and longer than the diameter of the cochlea?
Can you summarize, maybe with an example, what came out about during the Modena forum?

 

[LuiVerde]

I try to explain.
in attached files there is coclea_2.ipt. see how it was created ? it starts with a cylindrical profiling that is explained , on the created parallelepiped they are carried out sweeps that are nothing but the grooves of the step.( at the forum they created a classical augmentation and made a sweep of the tooth , but it is the same thing ) then it is folded and the game is done.
the substantial difference is the way to build it. What I want is built with a cylindrical cutter working on the side of the screw (I said ø 85 but it can be ø16 working on interpolation) while the normal screws are turned, or welded and can be obtained with a helid.

 

[Tarkus]

I try to explain.
....................................................................................................................................................................................................................................................................................................................................................................................................................................................................................... .

working for interpolation with the coclea that turns on the swivel head with the step you said before and doing more past, or working for interpolation but on exact mathematicians?

 

[LuiVerde]

if you have the cutter ø = seat you will advance the cutter of the step x turn if instead you have the cut + small so many passes to get the desired profile .
Hi.

 

[LuiVerde]

It is sure that they are exact maths.

see photo attached

 

[Tarkus]

It is sure that they are exact maths.

see photo attached

Okay, got it.
Thank you.
but your screws serve to rotate the bottles by 90°?

 

[LuiVerde]

No. It was just to make it clear that the profiles have to be exact, then you can do almost anything you want.

 

[torniaccio]

I subscribe in full lui_verde ... apparently it is not possible to generate to inventor sweep generated by solids.

I searched online and here on the forum but it seems to be an intrinsic problem of inventor.

I would also like to be able to shape my axles without having to rely on our trusted manufacturer, and I have the same problem in generating a twist that roars around a board my tablets.... Does anyone have any workarounds?