I dont know of a solution, or even a known problem, but I do know you will need to supply rather more information. Such as - what printers are attached (list of makes and models) and how are they attached (networked, USB plugin, wireless plugin, cable plugin). Also have any or all of them got any controller software that runs permanently, and has any of that control software got properties that include time-out settings. What do you do with the PC at the end of each day, does it get switched off, hibernated or put to sleep? What are the power-saving settings you have for your PC as a whole, and the printers in particular?
On top of all that, it will probably be necessary for you to describe how, or if, you allow printer drivers to automatically update themselves, and some history of when did this problem begin, and does the start of the problem coincide with any major change to the PC, such as adding new hardware, updating a service pack, suffering a virus infection etc.