Ribs and Slots pulling direction concept (Catia V5) 2

[rbarata]

Hello, my friends

I'm having a difficult time trying to understand what is the pulling direction concept used in Ribs and Slots.

I've done a lot of searches and 99,9% of the answers I find is the same as in Catia help files, which is "Pulling direction: sweeps the profile with respect to a specified direction.".

This is of no help to me mainly because when I create my own examples to confirm if I'm thinking correctly, the result are not the expected ones.

So, can someone explain what it is in your own words or point me to a site with a different explanation from the one above?

Many thanks in advance.

 

[supergee]

the best image I can find is this one: imagine the sketch is a person going up an escalator. lets say that the escalator has an inclination of 60 degrees. At the bottom, the person is standing up on the horizontal part of the escalator perfectly vertical. if you do not pull use pulling direction, that person would remain perpendicular to the escalator while going up: that is the head would tilt backward while going up.

by "pulling the direction" upwards, the person would travel at the vertical all the way up the escalator.

hope this helps

 

[jackk]

That's a great explanation!

 

[TibiX]

Hi rbarata,

When you create the profile and the guide, there is an initial inherent angle between them. For example, if your guide is an arc and at the start your profile plane is perpendicular to the arc you will have the following situations:
[ul]
[li]Profile control -> Keep angle : the profile will be pulled on the guide, keeping the original (when the sketches were created) angle, in any sections that are normal to the guide;[/li]
[li]Profile control -> Pulling direction : you define a line or a direction and the angle between them and the profile is kept constant.[/li]
[/ul]

In my example, the arc is opened at 90° and the guide is perpendicular to the profile at the start; the Z axis is paralel to the profile plane. The picture attached will speak a clearer message.

Hope this helps,
Best of luck!

CATIA V5R21 – mold tool design engineer

 

[rbarata]

I think I already understood it a bit better.

Image I create a Rib from a profile on the ZX plane.

If I select the YZ plane as a reference for the pulling direction, it still can rotate anywhere around the X and Y axis. (the condition "normal to YZ plane" is still satisfied).

In case my selection would be the XY plane, the profile could rotate around Z and Y axis. Am I correct?

Is so, one must think not in terms of the position of the profile in relation with the reference surface but rather in terms of the plane of the profile in relation with the reference surface.