Door closers are a simple, yet complex feat of engineering. Simply put, they are just a compound product made of two springs, a rack and pinion assembly, rubber-gasketed adjustment screws, filled & sealed with hydraulic fluid. The complexity arises when it was determined where to put the adjustment screws to dictate a certain action, whether it be the latching, sweeping, or back-check adjustments.
In years past, @ 30 years ago, we were provided this closer bodies as promotional products showing a cut-away view of Sargent's Door Closers and the engineering excellence they provide.
