As populations grew, epidemics became more commonplace and so too does the fear of being buried alive. Diseases like yellow fever could sometimes appear to kill its victim when they were really only in a coma. A number of people designed coffins that would allow the buried person to escape should they wake up six feet under.
The fear of being buried alive led Christian Henry Eisenbrandt to patent a “life-preserving coffin in doubtful cases of actual death.” In his application, he claimed that through a series of springs and levers, even the slightest motion of the head or hand would instantaneously open the coffin lid. – National Archives
I mean, the guys name is Fearnaught!?
There is no evidence to suggest these ever went into high production or were best-selling but the complicated designs are intriguing.