INHERITANCE

Hi ,


Want to know about Inheritance option in Pro-E. When to use this Option?


Can we use Inheritance Instead of Instances ( Family Table)?? Why ??

Use Inheritance as opposed to 'merge' fetatures when you wish to modifiy the geometry and /or feature list of an existing part. This function is not all that dissimilar to the 'flexible' feature seen at assembly level. However, you can only suppress features (and hence their children) through this feature. To add dimensions of an Inheritance feature you must first make them variable (in the same way you would with a flexible feature).


I can find no way to add the family table members of an inherited part to a family table.


Personally, I'd avoid it. I think there are too many shortcomings with it. Use merge instead (you can switch between them under the same feature).


Phil

There was a compelling presentation at the PTC|User conferenceon using the inheritance feature to replace a family table.


Because you can vary dimensions and suppress features in an inheritance, just like a family table, the models act like instances but are stand alone parts. Any change to the main model, propagates to the inherited models just like a generic does to the instances. Any dimensions or features set differently in the inherited models don't' change, just like the columns in a family table prevent changes from propagating to the instances.


What you don't have is the two directional tie between instances and generic, which can make datamanagement painful. If you make a change to an instance, it necessarily changes the generic (to update the table) which flags all the instances as changed. With the inheritance driven model, any change in an 'instance' doesn't effect the generic at all.


The only possible downside is automatic replacement of one instance for another via assy level family table isn't possible. You can replace manually using the 'by layout' option most likely without choosing new references.

as dgs said, data managment is pain.

I met Inheritance funcionality once in my previous job. It was used in big actuators assembly, as Family table member(the main asm have component from inheritance asm). Well, PDMLink 7.0 gave up when it had come to Check out and check in the whole Family table. There was no solution instead of deleting all inheritance components.

As I remeber right, those days weren`t the prettiest ones in my life))

One main reason I use Inheritance features is patterns. You
cannot publish a pattern using a publish geometry. Using an
inheritance feature allows you to create reference patterns that you
normally could not do with pubgeom or copygeom.



Another useful way of implementing inheritance features is with
inheritance cuts. Say you have a bunch of parts that are
interchanged in an assembly and you do not want to create assembly cuts
or add cuts to every part that is interchanged. You can create a
"cutout" part, adding solid geometry to represent the removed material
in the parts. Then, in each part you simply add an inheritance
cut and no matter which part is in session, you get the cuts and they
are driven from the "cutout" part.



Just some thoughts,

Jim

Please post an example for inheritance feature application.

Inheritance is totally different with Family table:


For Example:


1. Created the Casting part.


2. Created a Machining part, thenInheritance that Casting part into Machining part.From this point you can create a Machining part, because you want the both Casting and Machining parts are the same.

I don't know about posting an example, as I am a bit stretched for time. However, it is really easy.



1. Create a part where you have references you want to include in another part.

2. Inside the part where you need the references, click on Insert - Shared Data - Merge/Inheritance.

3. An open box will appear. Pick the reference part.

4. Assemble it to the part using a CSYS.

5. Click the "Toggle Inheritance" button on the dashboard if it wants to create a merge.

6. Click ok.



You now have a feature in the model tree that you can expand and see all of the references from the inherited part.



Play around with it. It is very simple, I promise.



Jim

I did a presentation at Pro/User in 2005 on inheritance features. It's supposed to be posted on the PTCUser Portal, but I don't see anything there. If there is enough interest in it, I can figure out a website to post it to.


Josh

jhouser,


You can upload the presentation on this website.....


If you look a the top of the page there is a file tab and an article tab. Go there and there is an upload tab that you can use. Admin will then vet the article and hopefully use it.


Kev

an example for use of Inheritance feature:


Cast part which is machined to get the final part which is used in an assembly...You need both the parts, and where any change made to the cast part should propogate to the machined part.


A Fabricated part, consisting of many plates which are welded as an assembly and then machined to get the final part.


These are the TWO examples that come to my mind.

Another handy thing regarding an inheritance, is that the dependence can be toggle on and off. It gives you a "base" part and you get to decide if you want your part to update if the base changes.

Hi All,

I have a case where I am about to replace a cast part from machining with another cast part without disturbing machining operations.

For Ex.

Machining part A
cast part B

Now i want to replace B with C in A.Please help to use merge or inheritance command in PRO-E.