A Mansfield man who badly injured his hand while building sets in 2011 for the Adam Sandler film “That’s My Boy ” has filed a lawsuit against Happy Madison Inc., Sandler’s production company, as well as Sony, Columbia Pictures and Black & Decker. Richard Houpert is seeking $1 million in damages as a result of an accident that resulted in the partial amputation of fingers on his right hand. In the suit filed this week in US District Court in Boston, Houpert says he was working on a “defective and dangerous” 3-horsepower Delta unisaw table saw when his right hand was drawn into the saw, causing serious injuries. Houpert, who’s represented by Belmont attorney Joan Amon, claims Black & Decker is negligent for not warning people about the saw’s “dangerous and defective characteristics,” and Sandler’s production company, as well as Sony, Columbia Pictures are negligent for not providing “reliable and safe” equipment. (It’s probably small consolation to Houpert, but “That’s My Boy” was panned by critics and cost $70 million to make but earned only $48 million worldwide.) Attempts to contact the defendants were unsuccessful.