DIN EN ISO 5459

[[Uw...]]

Hallo Messtechniker,

möchte gern eure Meinung zu folgender Zeichnungsangabe (siehe Skizze) haben:     Koax.Ø0,1 A (BB) SL

Ich würde folgendermaßen vorgehen:

Fläche A scannen und als äußeres Tangentialelement auswerten;

An den 6 Bohrungen Ø20 H7 je einen Zylinder messen;

Aus den 6 Zylinderachsen über Rückruf eine Mittelachse bilden;

Diese Achse mit der Ebene A schneiden.

Würdet ihr das Koordinatensystem auch so aufbauen?

Vielen Dank und schöne Weihnachten!

Uwe

 

Skizze.pdf

[[Ma...]]

That is new ISO also - unfortunately i don't have that book at home.

That circle for profile callout is telling in which direction you should evaluate. CZ will be common zone and SZ will be each face separately.
B-B will surelly mean pattern, but i am not sure now what is [SL].

[[na...]]

Please sign in to view this quote.

I would create a Best Fit Bore Pattern of the 6 20 mm diameter bores to datum A. This will create a new Best Fit datum system, which I would use as datum system for coaxiality/concentricity.

For profile's datum system, [SL] Straight Line is needed. In other words, you need 4 degrees of freedom locked from B-B pattern (2 rotation and 2 translation), but not the 5th rotation.

Where exactly on the part are features tolerated with profile?

[[Uw...]]

Hello,
Thank you for your answers.
If I place the part on the measuring plate so that reference A is at the top,
A already restricts 2 rotational degrees of freedom and one translational degree of freedom (in this case Z).

If I then enter a BestFit of the cylinder axes as the zero point (in this case in X and Y), what degree of freedom remains?

I probably don't have enough experience with the standard yet?

 

 

[[na...]]

Please sign in to view this quote.

 

There are 6 DoF, 3 rotations and 3 translations. With Best Fit Bore Pattern of the 6 bores to datum A you will get a new calculated Best fit with all 6 DoF locked.

In order to evaluate Coax.Ø0,1 there is no difference in datum system

|A|(B-B) [SL]| and

|A|(B-B)|

 

With |A|(B-B)| there are 6 DoF locked and with |A|(B-B) [SL]| the last rotational DoF is released, which has no impact when evaluating coaxiality.

 

I hope what I wrote makes some sense.