What engineers need to know about patents
This writing is directed to engineers. I make this point because I am an engineer (BSEE Brooklyn Poly) who became a patent attorney (New York Law School nights from 1988 to 1992) when the bottom fell out of the defense industry in the late '80s. For that matter, I'd rather deal with an engineer than other lawyers any day. Why? Why do you think?
Most engineers know what a patent is broadly; for example, a bundle of rights related to an invention. Utility (non-provisional) patents are just descriptions of how to make and use an invention that end with a set of patent claims. The description, typically referred to in patent lingo as the "disclosure," usually (preferably) includes drawings highlighting novel and non-obvious features thought to be an inventive improvement in some field ("art").
The written description of the invention should focus upon and describe the drawings in detail. The claims are the "meat and potatoes" of the patent and probably the most important part of a patent or patent application. The claims define the coverage, i.e., what the patent effectively "reads on," i.e., the "metes and bounds" of the patented subject matter. The claims are where the money is.
If you are preparing a patent disclosure for submission to your manager, patent attorney or for filing yourself, make absolutely sure that you include at least one drawing that truly communicates to other engineers the inventive feature. If you do so, everything else is secondary. If there is more than one inventive feature, there should be more than one drawing.
So as long as there is at least one drawing that shows the inventive feature(s) so that another engineer "gets" the invention, even if the patent attorney screws up the writing or claims, the drawing can be referred to as support to save the day. The Specification and claims can always be fixed with a declaration by the inventor as to what the drawing means to the skilled artisan, to make necessary corrections.
The reason that this is important is because once you file a patent application, you can never add new matter (35 USC §112), even to fix a minor mistake if the mistake goes to the core inventive feature. The only way to add new matter, post filing, is to refile the original application as a continuation-in-part (CIP) application. But with a CIP application, you have to live with the new filing date for the new matter, where the original filing date may be relied upon for claimed subject matter that only relies upon original disclosure.
Once you file a patent application, the filing date is your constructive date of invention. While you can evidence an actual date of invention now, the law is changing so that the US Patent system soon will be "first to file" as distinguished from "first to invent."
Once the new law takes affect (under the America Invents Act recently promulgated), everyone has to live with the filing date as the legal date of invention. You have to get it all in (and should get it all in fast) in view of the changing law.