Springs are one of the most common components in any mechanical system. If you are a machine design engineer you are more likely to come across modelling a spring while you are designing any machine sub assembly.

While designing springs is a whole topic in itself which involves all the calculations like what spring force is required, the working temperatures of the machine, the material properties required in the springs, etc. One of the questions anyone who has just started using Solidworks will have is, how do you actually mate springs with a shaft or a hole?

 

I will be showing quick tips on mating springs with a hole and a shaft by guiding you on how to constrain the spring and keep it where you want it inside the assembly. 

 

MATING SPRING WITH A HOLE

Firstly I have modeled a spring using a helix curve and the swept command together. Remember the center of the base circle sketch that you will be using for creating the spring must coincide with the origin of the part’s coordinate system. The significance of this will be realized later.

Then we cut the edges off to make the surfaces easy to mate. If you have noticed spring suspensions carefully you may remember that’s how suspension springs were made with those cut edges. So now we get the spring which we are going to be working with.

 

This is how the spring and the hole looks like. 

 

Now I will simply mate the base edge face of the spring that we made flat by using the extrude cut feature with the base face of hole by using a coincident mate. Then I will go to visibility options and press the show temporary axis button. After doing this my assembly will look something like this.

I then select the origin of the spring and the temporary axis of the hole to mate them coincident and hence the job is done. The spring is free to rotate around its axis and is constrained the way it should be.

MATING SPRING WITH SHAFT

The procedure of mating the spring with a shaft will remain the same as that of mating it with the hole just remember to keep the origin and the center of the spring’s base circle coincident.