Closed loop control system for producing a sealed pouch

• Main Authors: LABER DAVID I, ELLSWORTH W. DAVID, POWELL LARRY J
• Format: Patent
• Language: English
• Published: 17.09.2002
• Edition: 7
• Subjects: AFTER-TREATMENT OF THE SHAPED PRODUCTS, e.g. REPAIRING; CONTROL OR REGULATING SYSTEMS IN GENERAL; CONTROLLING; FUNCTIONAL ELEMENTS OF SUCH SYSTEMS; INDEXING SCHEME ASSOCIATED WITH SUBCLASS B29C, RELATING TO PARTICULARARTICLES; MONITORING OR TESTING ARRANGEMENTS FOR SUCH SYSTEMS ORELEMENTS; PERFORMING OPERATIONS; PHYSICS; REGULATING; SHAPING OF MATERIAL IN A PLASTIC STATE, NOT OTHERWISE PROVIDEDFOR; SHAPING OR JOINING OF PLASTICS; TRANSPORTING; WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE, IN GENERAL

A system for maintaining a desired sealing force is provided, which incorporates a closed loop control system. The system includes a platen, which has a surface for making contact with one or more items to be sealed, a motor for producing a linear movement, a linkage coupled to the platen and the motor for transferring the linear movement produced by the motor to the platen, and a transducer coupled between the linkage and the platen for measuring the force applied to the platen via the linkage through the linear movement of the motor and producing a signal representative of the force measured. A motor controller produces a motor control signal, which is supplied to the motor for controlling the same. The motor control signal is used to control the linear movement produced by the motor. The motor controller further receives the feedback signal from the transducer, and correspondingly adjusts the value of the control signal used to control the magnitude of the linear movement.