Abstract: An improved method and apparatus for enabling unsupported packaging film (e.g., low density polyethylene, linear low density polyethylene, and high density polyethylene) to be sealed in a tube in the process of making a flexible package. A “following belt” is provided which allows for a sandwiching effect to be imported on the film as it passes through its welding zone. In the prior art, while in this welding zone the polyethylene film would move with a conventional band seal assembly. But the opposite side of the polyethylene film would have to move relative to a drag iron this causing potential friction, seam failure and poor tracking. The present invention's use of a following belt allows the elements on both sides of the unsupported film to move with the film.

Abstract: A product delivery system and method are provided including an electromechanical vibratory conveyor which has a product conveying member, a vibrator for vibrating the product conveyor and a control system for controlling electronically the vibration of the product conveying member both statically and dynamically to optimize performance both with and without product on the product conveying member. The vibration of the product conveying member is tuned both statically and dynamically with a coarse tuning followed by a fine tuning. An improved pulse width modulation drive circuit for the vibrator includes vibrating frequency and amplitude varying devices for adjusting the frequency and amplitude of the vibrator for increased efficiency, optimized performance and reduction in energy consumption. Several redundant safety devices to safeguard the switching devices and the vibrator are also provided.

Abstract: A product delivery system and method are provided including an electromechanical vibratory conveyor which has a product conveying member, a vibrator for vibrating the product conveyor and a control system for controlling electronically the vibration of the product conveying member both statically and dynamically to optimize performance both with and without product on the product conveying member. The vibration of the product conveying member is tuned both statically and dynamically with a coarse tuning followed by a fine tuning. An improved pulse width modulation drive circuit for the vibrator includes vibrating frequency and amplitude varying devices for adjusting the frequency and amplitude of the vibrator for increased efficiency, optimized performance and reduction in energy consumption. Several redundant safety devices to safeguard the switching devices and the vibrator are also provided.

Abstract: A method and apparatus for settling product in a servo-controlled vertical form, fill and seal machine where the product, when inserted into a partially-formed tubular bag, normally does not adequately settle without further action by the machine. The invention utilizes motion control of a servo motor to provide a settling action for product inside the partially-formed bag to introduce instability to cause settling in the bag at a very high frequency during continuous motion of the film and the film tube.

Abstract: A method and apparatus for a vertical form, fill and seal machine to produce a constant pull length of the film and therefore packages of consistent length, whatever the velocity of the machine. When the film is pulled, and the pulling ceases, there is always a finite overrun of pulled film. The method according to the invention determines the velocity for operation of the machine while accounting for the overrun in order to produce packages of constant length. The apparatus includes a motion controller for calculating the velocity and operating the machine at the calculated velocity during the time that the film is being advanced in the vertical form, fill and seal machine.

Abstract: An apparatus and method for stripping the end seal area in a vertical form, fill and seal machine. First and second wiper members are secured to the sealing jaws and extend toward the film tube being formed, filled and sealed. The wiper members have engagement portions vertically staggered or offset from one another which engage opposite sides of the film tube for the purposes of stripping. The stripping apparatus and process can be used with intermittent machines which use film reversal for stripping, as well as continuous motion machines which always advance the film in the forward direction.

Abstract: A method and apparatus for use in a vertical form, fill and seal machine to protect the longitudinal back seal. A pair of clamps retains the plastic film against the forming tube on either side of the back seal and on either side of a sealing platen if the platen is used for forming the back seal. The clamps extend for at least the length of the platen, and the clamps are operated together in unison.

Abstract: An orientation device for vertically orienting products in a vertical form, fill and seal machine. It includes a product receipt station for receiving a plurality of unoriented products and a product discharge station for discharging a plurality of oriented products. The products are indexed in discrete groups from the product receipt station to the product discharge station, during which the products of each group are oriented with their longitudinal axes being essentially vertical.