"To be patentable, an invention must be: novel, nonobvious, and useful. The novelty requirement prevents the patenting of something that is known, If the invention is described in a printed publication or patent, or if it is sold anywhere in the world, it is not novel. Nonobvious means that the invention could not have been conceived by someone “having ordinary skill in the art” without undue experimentation. The initial burden to show obviousness is on the patent examiner at the USPTO. The applicant can then rebut the presumption of obviousness. The useful criteria simply requires that the invention have some utility or function and be beneficial to society. Normally this criterion is met easily."
In the patent process you submit schematics drawings and technical data the patent office dose not have room for the actual items which in some cases cane fill an entire room or building.