Hinge simulation 1

[sbmathias]

New user trying to model a simple pair of hinges. I got one hinge to work in an assembly file. By "work", I mean I could drag one leaf back and forth given its degrees of freedom.

I now place two of these hinge assemblies into another assembly. Each hinge has one leaf attached to an immovable object. I tried attaching the "free" leaf to a rigid object face, to allow the SW user to drag the object back and forth through an arc. However, when I try this, I get a message saying object is immovable. I also tried mating the two movable leaf faces to be coincident, but that didn't seem to work either.

It seems like this should be a pretty easy thing to do. What am I missing??

 

[SBaugh]

Do you have Flexible assembly on?

I know there is limitation (SW04) with having more then one of the same sub-assemblies set to flexible. Only one would work.

Regards,

Scott Baugh, CSWP

http://www.3dvisiontech.com

http://www.scottjbaugh.com

faq731-376

 

[MadMango]

I take it you have an assembly of the 2 hinge halves, in the top level assembly with your fixed part, hinge and moveable part?

Right-click the hinge assy and select Properties. In the lower-right corner, there should be an area called Solve As with 3 options. Select Flexible.

For more info see SW Help index for [blue]flexable sub-assemblies[/blue].

[blue]"But what... is it good for?"[/blue]
Engineer at the Advanced Computing Systems Division of IBM, 1968, commenting on the microchip.
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[sbmathias]

I didn't insert the two hinge halves as an assembly into the final top-level assembly. I inserted them as individual hinge halves into the final assembly. Do I need to do otherwise to get this to work?

 

[MadMango]

I now place two of these hinge assemblies into another assembly.

It sounded like you did.

If you only placed each half into the assy, then you should be able to mate one half to your fixed part and the other half to another part. A simple concentric mate at the center where the pin should be should provide the DoF you are looking for. It should work, we must be missing something.

[blue]"But what... is it good for?"[/blue]
Engineer at the Advanced Computing Systems Division of IBM, 1968, commenting on the microchip.
Have you read faq731-376 to make the best use of Eng-Tips Forums?

 

[sbmathias]

I guess I'm guilty of mis-typing my procedure. I did place the two halves of the hinges individually. I did then put concentric mates on the pins, as well as coincident mates on the bearing surfaces, on all concerned parts. After this, each hinge would work correctly when you dragged the leaf through an arc.

However, when I mated the item to be hinged to the free leaves, it didn't jump into position on the leaf, nor could I rotate the item through the arc.

I'll try some of the Flexible suggestion and see if that changes anything.

 

[CorBlimeyLimey]

Sounds like the "item to be hinged" is constrained in such a way as to not allow movement or rotation. Check or suppress it's mates.

from (the City of) Barrie, Ontario.

I tried sniffing Coke once, but the ice cubes got stuck in my nose

 

[MadMango]

OK, then I would take the "part to be hinged" and create a new assy of it with the hinge half that should be connected to it. Then drop that into your top level assy, and mate accordingly. That should provide you with what you are looking for.

[blue]"But what... is it good for?"[/blue]
Engineer at the Advanced Computing Systems Division of IBM, 1968, commenting on the microchip.
Have you read faq731-376 to make the best use of Eng-Tips Forums?

 

[sbmathias]

Thanks to all for the various suggestions. I'll let you know when I get it to work.

 

[ctopher]

SW2005 has a tutorial for creating a hinge with equations/config's. Works well.

 

[TheTick]

Overall, I think trying to make the hinge move independently in a model as a subassembly may be asking too much. Take it from a guy who currently designs hinges for a living.

When designing hinge movement, I usually find it necessary to split the entire top level assembly into two main subassemblies, a fixed portion and a moving portion. Half the hinge goes on the fixed portion, and half on the moving.

Define the pivot axis as in each of the two main subassemblies using sketches to place a main datum axis. This helps avoid mate trouble.

As far as the BOM goes, try inserting the "working" hinge leaves as envelopes.