Patent ID: 7338283

Claim:
A device for detaching a break-away panel part of a dental model molding tray from a hollow body part of said tray which encloses said break-away panel, said break-away panel being located between upper and lower surfaces of said body of said molding tray and being joined by frangible members to horizontally aligned flange walls which protrude inwardly towards said panel from inner sides of a peripheral wall of said hollow tray body, said device including; a. a template comprising a body which includes, (I) a base (ii) a peripheral flange wall which protrudes upwardly from said base, (iii) a recess formed between an upper surface of said base and inner surfaces of said peripheral flange wall, said recess being of a proper size and shape to vertically downwardly receive therein said hollow body of said tray, with said lower surface of said tray body parallel to and above said upper surface of said template base, and with outer upstanding surfaces of said tray perimeter wall adjacent to said inner facing upstanding surfaces of said peripheral flange wall of said template, and (iv) at least one rib-shaped lug which protrudes upwardly from said upper surface of said template base, said lug having a flat upper surface which is located a greater distance above said upper surface of said template base than the distance between a lower surface of said break-away panel and said lower surface of said hollow tray body, whereby said lug supports said break-away panel to thereby locate said lower surface of said hollow tray body above said upper surface of said template, and b. force exerting means for exerting a downwardly directed force on at least a first abutment flange which protrudes outwardly from said tray body relative to said template, whereby a reaction force is exerted upwardly on said break-away panel relative to said tray body sufficient to break said frangible members joining said break-away panel to said flanges, said force exerting means including a knock-out tool which has a plurality of at least three circumferentially spaced apart, downwardly protruding lower abutment flange-contacting members for contacting an upper surface of said abutment flange of said tray, and an upper anvil surface rigidly coupled to said flange-contacting members and adapted to receive a downwardly directed impact.