The basic components of an electrospinning apparatus are:
The goal of electrospinning is to utilize an electric field to pull a polymer solution onto a metal collecting plate. A high voltage power supply is used to charge a polymer solution, which is placed in close proximity to a metallic collecting plate. If designed correctly, the polymer will become charged and be pulled onto the target in fibers that are on the nano-scale. As you can see in the above diagram, there is a balance of forces between the surface tension of the polymer and the strength of convection. In an optimal situation, the surface of the polymer forms a Taylor Cone which is then spun as a fiber onto the target. The setup needs to be designed to have enough voltage to pull the fibers onto the plate, but not so much voltage that it breaks the fibers apart. The solution also needs to be designed to have enough surface tension to form the Taylor Cone, but not so much surface tension that it will not be pulled to the target. This makes electrospinning an excellent opportunity for engineering, as there are a number of variables to play with.
For a more detailed description of electrospinning, you can check out: