The springs function is to place pressure on the roller. The roller is in fact a registration roller. There should be one on both ends of the roller. It runs against the black rubberised roller and guides the paper through at the correct pressure on both sides of the paper. Usually this will be ok unless you are using a heavy media type, such as 150 gsm+, then you might experience skewing or even jamming in the worst possible senario. So, for normal 80/90gsm paper it should be fine.
Rob Simmonds, January 2009
