DEVICE FOR MOLDING AND BLANKING ARTICLES FROM SHEET THERMOPLASTIC MATERIAL Russian patent published in 2002 - IPC

FIELD: pressure shaping of thermoplastic materials and blanking molded articles in molding unit. SUBSTANCE: proposed device includes molding unit which consists of upper and lower molding members. Lower molding member is provided with cutting edge and is connected with vertical reciprocating motion drive. Device contains slider-crank mechanism, pneumatic retainer and first and second sensors showing positions of lower molding member. Drive of lower molding member is made in form of pneumatic cylinder on which pneumatic retainer is mounted; this pneumatic retainer is engageable with of said pneumatic cylinder. Pneumatic cylinder is rigidly connected with strut of slider-crank mechanism whose drive member is piston with rod of pneumatic cylinder and driven member is lower molding member. Outputs of first and second position sensors of lower molding member are connected through pneumatic main with inlet of pneumatic retainer and above-piston chamber of pneumatic cylinder, respectively. Strut of slider-crank mechanism is made in form of frame whose upper base has holes for vertical movable guides connected with lower molding member. Rigidly secured to lower base of frame is pneumatic cylinder. First and second position sensors of lower molding member are located along line of travel of piston with rod of pneumatic cylinder. First and second position sensors of lower molding member are made in form of limit switches fitted on vertical rods of frame of slider-crank mechanism whose movable contact are secured on rod of pneumatic cylinder. First and second position sensors of lower molding member and pneumatic cylinder are magnetic in construction. Position sensors of lower molding member are mounted on external surface of pneumatic cylinder sleeve; first sensor is located below second sensor. EFFECT: enhanced accuracy of control of motion of lower molding member and blanking articles; increased productivity; reduced power requirements. 5 cl, 3 dwg