Top-off and weighing apparatus for filling bags

Abstract

A device for topping-off a substantially filled bag with a final charge of particulate material to provide a predetermined final charge weight in the bag is herein disclosed. The device comprises a lower frame supported upon a plurality of load cells and an upper frame supported above the lower frame also upon a plurality of load cells. The upper frame has rotatably suspended therefrom a pair of carriage assemblies which support respective housings. Each of the housings has disposed therein a belt capable of linear motion. The belts are exposed on an inner face of each of the housings such that when the carriage assemblies are rotated toward one another, the respective belts meet one another and are able to engage the opposed faces of a bag. A plurality of bag grasping means are mounted upon the respective housings so as to be able to grasp and hold the opposed faces of the bag received between the belts to open the bag as the housings are rotated away from one another. A filling structure is supported independent of the upper and lower frames and is arranged to supply a charge of particulate material to the open bag. A signal processor for integrating electrical signals from the plurality of load cells of the respective upper and lower frames calculates an actual weight of the bag, determines the difference between the actual weight of the bag and the desired final charge weight of the bag, and directs the filling structure to supply the charge of particulate material to the bag to attain the final charge weight.