Part family - assembly constraint problem

Hi all.

 

Here is a problem that has been keeping me busy/driving me crazy for 3 days now.

 

I have created a family of parts for cylinders: rod.sldprt; Body.SLDPRT and Assembly: Cylinder.SLDASM

As for the parts, everything is fine. It is at the level of distance constraints in the assembly that the problem arises.

I use the limit distances to represent the operation of the cylinders: closed length and length at the bottom of the stroke. I create my part family via automatic creation, then fill in the columns for the parameters of interest and the rows for the different configurations (about 50). 

Where it gets really strange: while at first everything seems to work, some values change in my Excel spreadsheet! For example, in the image below (see image), when I open the part family (right click > edit the part family), the lengths in D5 and E5 are systematically incremented by -282.19 mm (I started with values of 305 and 455). It's hard to understand... (already checked: there is no hidden formula in the Excel cell, and this value of 282.19 mm does not correspond to anything in the construction of the assembly or any of the parts)

Another problem: SW persists in recalculating the mass of my first configuration (1125.961 in H3 cell), while I impose the value 1700 on it. 

Thank you for your help, I'm running out of ideas. What I'm trying to do is simply insert values and then prevent them from changing... However, I checked in SW "Prohibit changes to the model that would update the family of parts", so I don't understand ANYTHING anymore.

Hello, we have abandoned the idea of having flexible cylinders with limited distances: there are too many bugs. We have an in-based configuration, an out-out configuration, and we can draw the trajectory with the trajectory function of SolidWors. We sometimes use free configurations, but only to test in the assembly, without any distance limit because the two together are a disaster!

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Hello

What version do you have of Solidwoks? Sp5 for versions prior to 2016 and Sp3 for 2016?

You have already copied all your configuration settings into another excel file and deleted the table then recreated it and pasted it back in???

Otherwise I do without excel file. I do my asm with the constraints as it should be and then I go to configuration and I create another one and there modify by double clicking on the asm and there all the dimensions appear and click on those to modify and at the end of the dimension box you can choose (this config or all the configs or specify the config)...


famille_de_pieces_-_probleme_contrainte_dassemblage.png
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Hello

Thank you .PL, I left for something else in the end. I created an additional body at the end of the rod (which is therefore in the body of the cylinder) and I use the Solidworks slide constraint. I have a small inaccuracy of about 1-2 mm but for my application, it is not a problem.

@ac cobra 427 yes I tried and nothing helped.... As for your proposal to do everything manually, I have more than 200 configs to do so I don't have the courage (and especially not the desire) to do all this on the hand!!

And to answer your question, 2016SP3 ;-)

Thanks again to both of you!

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For your information, SP4 was released a few days ago.

I found a way around the difficulty.

I created an additional body at the end of the rod (which is therefore in the body of the cylinder) and I use the "slide constraint" of Solidworks. I have a small inaccuracy of about 1-2 mm but for my application, it is not a problem. The distance limit method is to shoot yourself ...

Thank you for your answers :-)