naming convention of part files for assembly files

In SolidWorks, I have an assembly file bb.sldasm
with part files
bb1.sldprt
bb2.sldprt

when I save the assembly file as STL format,
two files are saved:
bb1-1.stl
bb2-1.stl

What the postfix "-1" means? In what circumstances will numbers other
than 1 appear?

(At first I guess postfix other than 1 would occur when part files with
the same file name but in different directories are included in the
assembly file. But it seems that SolidWorks does not allow me to do so.
It shows error.)

Thanks for advice!~

 

If for instance bb1.sldprt was a toy car and you have four (4) wheel/tire
combo parts and you save the bb.sldasm then you will have a bb1-1.stl,
bb1-2.stl, bb1-3.stl and bb1-4.stl.

HTH,
Muggs

 

Sorry this is clearer (more Clear?)

If for instance toycar.sldasm was a toy car and you have four (4) wheel/tire
combo parts called bb1.sldprt and you save the toycar.sldasm then you will
have a bb1-1.stl,
bb1-2.stl, bb1-3.stl and bb1-4.stl.

HTH,
Muggs

 

bb1-1 means that it is the first instance of bb1. It is the same for
bb2-1. Put another bb1 in the assembly and see what happens.

 

i see. thank you!