Apparatus and method for weighing product during filling

Abstract

A slurry product is packaged into a plastic bag using a modified form-fill-seal apparatus. A method for making a plastic bag filled with a desired weight of a slurry material on a form/fill/seal machine, includes drawing a plastic film over a mandrel of a form/fill/seal machine and wrapping the film around a forming tube. A tube of plastic film is formed by bonding the edges of the film together and the bottom of the tube is sealed. An initial weight is obtained by weighing the mandrel and the tube of plastic film then a slurry composition is deposited inside the closed tube. The present weight of the mandrel, tube of plastic film and contents of the tube are monitored as the slurry is deposited, and the present weight and the initial weight are compared until a desired weight is reached. After the desired weight is reached, the filled bag is sealed and separated from the tube of plastic film.

1 . A method for making a plastic bag filled with a desired weight of a slurry material on a form/fill/seal machine, comprising:
 drawing a plastic film over a mandrel of a form/fill/seal machine;   wrapping the film around a forming tube;   forming a tube of plastic film by bonding the edges of the film together;   sealing the bottom of the tube to form an attached bag;   weighing the mandrel and the tube of plastic film to obtain an initial weight;   depositing a slurry composition inside the closed tube;   monitoring the present weight of at least the mandrel, tube of plastic film and contents of an attached bag as the slurry is deposited;   comparing the present weight and the initial weight until a desired weight is reached;   sealing the attached bag; and   separating the filled, sealed attached bag from the tube of plastic film.   
   
   
       2 . The method of  claim 1  wherein said depositing step includes using at least one auger to move the slurry from a hopper to the bag. 
   
   
       3 . The method of  claim 1  further comprising weighing the contents of the attached bag using load cells. 
   
   
       4 . The method of  claim 1  wherein said second sealing step and said separating step occur substantially simultaneously. 
   
   
       5 . The method of  claim 1  wherein said monitoring step is performed by a computerized controller. 
   
   
       6 . The method of  claim 1  wherein said filling step further comprises positioning the a bulk auger and a precision auger to feed slurry from opposite sides of the attached bag. 
   
   
       7 . The method of  claim 1  further comprising sending the sealed bag for stacking on a palette. 
   
   
       8 . An apparatus for forming and filling a bag of a slurry composition comprising:
 a first support;   a slurry product dispenser mounted to the first support and comprising a hopper and at least one feed auger;   a second support;   a bag former attached to the second support and comprising a forming tube having a plastic film wrapped thereon and an attached bag descending from the forming tube;   load cells associated with exactly one of the first support and the second support, configured to detect the weight of the slurry product as it is transferred from the said first support to said second support;   a bag sealer; and   a controller in communication with said load cells, wherein the controller causes slurry product to be dispensed into the attached bag until a target weight is reached, then causes the attached bag to be sealed.   
   
   
       9 . The apparatus of  claim 8  wherein the product dispenser further comprises a bulk auger and a precision auger. 
   
   
       10 . The apparatus of  claim 9  wherein the bulk auger is from about 2.5 inches to about 3.5 inches in diameter. 
   
   
       11 . The apparatus of  claim 9  wherein said precision auger is from about 0.8 inches to about 1.2 inches in diameter. 
   
   
       12 . The apparatus of  claim 8  wherein said bag former comprises a forming tube assembly. 
   
   
       13 . The apparatus of  claim 12  wherein said first support is a primary frame and said second support is an inner support assembly that contacts said primary frame only at a load cell. 
   
   
       14 . The apparatus of  12  above wherein said forming tube assembly further comprises a forming tube, a mandrel and at least one mounting plate. 
   
   
       15 . The apparatus of  claim 8  wherein said frame further comprises an upper mounting plate and said upper mounting plate is supported by said mounting plate with forming tube supports. 
   
   
       16 . The apparatus of  claim 8  wherein said frame further comprises a swingable arm mounted to said frame that supports at least one component of the sealer.