I often work with 3D CAD models, which I receive as SolidWorks or PDF files. I need to turn them into black & white line art, like you'd find in a patent application. (In fact, exactly like what you find in a patent application!)
Acrobat-9 allows me to rotate & scale the models, so I can print them with reasonable resolution, but the rest of my drawing toolchain deals with SVG files, while all I can get out of Acrobat is bitmaps. (I also make models from scratch in Blender, and make line drawings using rendering procedures there, but that also produces bitmaps.)
Is there some way to get from a 3D view to an SVG picture (preferably with relatively simple Bezier curves and scaled line weights)?
(As an example, imagine that I have a 3D model of a cube. I position it as desired, then (somehow) convert it to an SVG image with several straight lines where the edges are, with the line weights scaled according to the distance between the edge and the camera/viewer.)
if you have rendered views as PDF files, you can use inkscape's command-line tool to convert PDF to SVG, as discussed on this post.
case there are no rendered PDF's available, you can export PDF snapshots from within CAD prior to converting them.
you can also try other converters made for this purpose, like verydoc or PDF-tron.