How can I share animation clips between character models?

I have a model which has several animaions.

All those animations of the model are included in the model file, so the exported fbx file from 3dsmax is only one.

There is no problem to import the model and make it to be animated in Unity as following on the document, Character Animation.

Now, how can I share all of the animations of the model with other models?

There is another character model but this does not have any animation clips but only has joint infomation via rigging. (I mean the model has its skeleton at least)

Then it is exported to fbx and imported into Unity. Next, what should I do to share and assign all animations of the first model's?

Thank you.

If I am following your question, you should be able to add the Animation component to the GameObject then set how many animations you want to assign and either drag or select them from the drop down. Now whether these will actually play on your model with the results expected truly depends on the rig, weighting, etc. and if those are similar to initial skeleton. HTH.