Top-off and weighing apparatus for filling bags

• US 5,979,512 A
• Filed: 08/04/1998
• Issued: 11/09/1999
• Est. Priority Date: 08/05/1997
• Status: Expired due to Term

• Current Assignee: Thiele Technologies, Inc. (Barry-Wehmiller Group Incorporated), Slidell, Inc.
• Original Assignee: Slidell, Inc.
• Inventors: Snaza, Kurt, McGregor, James R., McGregor, Harold R., Wobschall, LaVern
• Primary Examiner(s): Recla, Henry J.
• Assistant Examiner(s): Huynh, Khoa D.
• Application Number:
  US09/128,866
• Time in Patent Office: 462 Days
• Field of Search: 141/83, 141/10, 141/114, 141/129, 141/156, 141/157, 141/166, 141/168, 141/313, 141/317, 141/314, 141/315, 53/502, 177/116, 177/160, 177/119
• US Class Current: 141/83
• CPC Class Codes: B65B 1/32 by weighing check-weighing of filled containers or receptacles B65B1/46
• CPC Class Codes: B65B 43/30 by grippers engaging opposed walls, e.g. suction-operated
• CPC Class Codes: G01G 13/04 involving dribble-feed means controlled by the weighing mechanism to top up the receptacle to the target weight

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.

Claims

1. A device for topping-off a substantially filled bag with a final charge of particulate material to provide a predetermined total charge weight in the bag, the device comprising:

a lower frame supported upon a plurality of lower load cells, the lower frame having mounted thereon a receiving platform which supports most of the weight of an initially filled bag received thereon;

an upper frame supported above the lower frame upon a plurality of upper load cells;

a pair of carriage assemblies suspended from the upper frame and movable towards and away from each other between open and closed positions;

a plurality of bag grasping means mounted upon the respective carriage assemblies so as to be able to grasp and hold the opposed faces of the bag received between the carriage assemblies and further being capable of opening the bag as the carriage assemblies are moved away from one another to their open position, whereby a portion of the weight of an initially filled bag and of a top-off charge of material added to the bag is supported by the upper frame and thereby transferred to the upper load cells;

a filling mechanism supported independent of the upper and lower frames, the filling structure positioned to supply a predetermined charge of particulate material to an open bag; and

a signal processor connected to the lower and upper load cells for integrating electrical weight signals received therefrom, the signal processor being capable of calculating an actual weight of the bag, of determining the difference between the actual weight of the bag and the final charge weight, and of actuating the filling mechanism to supply a charge of particulate material to the bag to attain the predetermined total charge weight.

2. The device for topping-off a substantially filled bag of claim 1 wherein each of the carriage assemblies further comprise:

a pair of pivot legs pivotally suspended from a pivot shaft that is coupled to the upper frame.

3. The device of claim 1 wherein each of the upper and lower frames are supported upon at least two load cells.

4. The device for topping-off a substantially filled bag of claim 1 wherein the upper frame is supported upon two load cells.

5. The device for topping-off a substantially filled bag of claim 1 wherein the carriage assemblies are rotatable mounted and constrained to rotate in symmetry with one another by at least one tie rod coupled between the respective carriage assemblies.

6. The device for topping-off a substantially filled bag of claim 5 wherein the carriage assemblies are rotated toward and away from one another by at least one carriage cylinder having a first end affixed to the upper frame and a second end coupled to a carriage assembly.

7. The device for topping-off a substantially filled bag of claim 5 wherein the carriage assemblies are rotated toward and away from one another by at least one carriage cylinder having a first end coupled to a first carriage assembly and a second end coupled to a second carriage assembly.

8. The device for topping-off a substantially filled bag of claim 1 further comprising a pair of housings, each of the housings of the pair being supported by a respective carriage assembly, each housing having disposed therein a belt, the belts being capable of linear motion, the belts being exposed on an inner face of each housing such that when the carriage assemblies are moved to their closed position, the respective belts meet engage the opposed faces of a bag.

9. The device for topping-off a substantially filled bag of claim 8 wherein the housings operate in a complementary manner and wherein the housings further comprise:

respective serpentine belts received upon a plurality of pulleys mounted within the respective housings, at least one of the pulleys of each housing being a drive pulley, the respective drive pulleys being mounted upon, and driven by, respective drive shafts which extend out of each of the housings;

respective spur gears affixed to each of the drive shafts of the housings, the respective spur gears mating when the housings are moved into contact with one another; and

a motor mounted upon one of the housings, the motor inducing linear motion in the respective serpentine belts of the complementary housings by providing motive power to the drive shaft of the belt of the housing upon which the motor is mounted, the motive power being transferred to the belt of the complementary housing through the mating of the spur gears affixed upon the respective drive shafts of the housings when the housings are rotated into contact with one another.

10. The device for topping-off a substantially filled bag of claim 1 wherein the receiving plate form comprises a conveyor.

11. The device of claim 1 wherein the bag grasping means comprise a plurality of vacuum suction devices mounted upon and in fluidic connection with a pair of vacuum manifolds that are slidably mounted upon the respective housings, the vacuum manifolds having associated therewith means for inducing a vacuum therein and hence, in the vacuum suction devices, the respective vacuum manifolds being also coupled to respective cylinders, the cylinders being arranged to slide the vacuum manifolds towards and away from the inner face of the housings, the vacuum suction devices being capable of engaging the opposing faces of a bag received between the housings when the vacuum manifolds are in a closed position adjacent the inner face of the housings.

12. The device of claim 1 wherein the fill spout comprises a vertical auger bag filling machine.

13. A method of achieving, within an acceptable margin of error, a total charge weight of particulate material contained within a bag, the method comprising the steps of:

conveying a bag containing a preliminary charge weight of particulate material onto a receiving platform supported upon a plurality of load cells;

engaging the opposing faces of the bag between a pair of carriage assemblies, the carriage assemblies being suspended from a frame that is supported by a plurality of upper load cells;

grasping the opposing faces of the bag with a plurality of grasping means mounted upon the carriage assemblies after the opposing faces of the bag have been fully engaged by the carriage assemblies;

moving the carriage assemblies away from each other to open the top of the bag;

recording a first electronic signal from the plurality of the lower load cells supporting the receiving platform that corresponds to the weight of the bag supported upon the receiving platform;

recording a second electronic signal from the plurality of the upper load cells supporting the carriage assemblies upon which the grasping means are mounted that corresponds to the portion of the weight of the bag and preliminary charge weight supported by the carriage assemblies;

integrating the first and second electronic signals to determine the preliminary charge weight and to determine the difference between the total charge weight and the preliminary charge weight, if any;

causing a fill spout to add a quantity of particulate material to the bag based upon the difference between the final charge weight and the preliminary charge weight;

repeating the recording, weighing and integrating steps as needed to achieve the final charge weight of particulate material within the bag;

rotating the carriage arms towards one another to re-engage the opposing faces of the now filled bag between the carriage assemblies and close the top of the bag;

disengaging the grasping means from the opposing faces of the bag; and

conveying the filled bag from the receiving conveyor to a bag closing station.

14. A device for topping-off a substantially filled bag with a final charge of a particulate material to provide a predetermined final charge weight in the bag, the device comprising:

a lower frame supported upon a plurality of lower load cells, the lower frame having mounted thereon a receiving platform;

an upper frame supported above the lower frame upon a plurality of upper load cells;

a pair of carriage assemblies suspended from the upper frame and movable towards and away from each other between open and closed positions, the carriage assemblies constrained to rotate in symmetry with one another by a tie rod coupled between the respective carriage assemblies, the movement being enabled by at least one carriage cylinder having a first end affixed to the upper frame and a second end coupled to one of the carriage assemblies;

a pair of housings, each of the housings of the pair being supported from a respective carriage assembly, each housing having disposed therein a belt, the belts being capable of linear motion, the belts being exposed on an inner face of each housing 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, the bag grasping means being mounted upon the respective housings so as to be able to grasp and hold the opposed faces of the bag received between the belts of each housing and further being capable of opening the bag as the housings are rotated away from one another;

a fill spout supported independent of the upper and lower frames, the fill spout being capable of being lowered into an open bag supported by the bag grasping means of the upper frame and the receiving conveyor of the lower frame, the fill spout being further capable of supplying a predetermined charge of particulate material to the open bag; and

a signal processor for integrating electrical signals received from the plurality of load cells of the respective upper and lower frames, the signal processor further being capable of calculating an actual weight of the bag, of determining the difference between the actual weight of the bag and an ideal weight, and of directing the fill spout to supply a charge of particulate material to the bag to attain the desired final charge weight.

15. The device for topping-off a substantially filled bag of claim 14 wherein each of the upper and lower frames are supported upon at least two load cells.

16. The device for topping-off a substantially filled bag of claim 14 wherein the upper frame is supported upon two load cells.

17. The device for topping-off a substantially filled bag of claim 14 wherein the housings operate in a complementary manner and wherein the housings further comprise:

respective serpentine belts received upon a plurality of pulleys mounted within the respective housings, at least one of the pulleys of each housing being a driven drive pulley, the respective drive pulleys being mounted upon, and driven by, respective drive shafts which extend out of each of the housings;

respective spur gears affixed to each of the vertical drive shafts of the housings, the respective spur gears mating when the belts of the housings are rotated into contact with one another; and

a motor mounted upon one of the housings, the motor providing motive power to induce linear motion in the serpentine belts of the complementary housings by providing motive power to the drive shaft of the belt of the housing upon which the motor is mounted, the motive power be transferred to the belt of the complementary housing through the mating of the spur gears affixed upon the respective drive shafts of the belts of the housings when the housings are rotated into contact with one another.

18. The device for topping-off a substantially filled bag of claim 14 wherein the bag grasping means comprise a plurality of vacuum suction devices mounted upon and in fluidic connection with a pair of vacuum manifolds that are slidably mounted upon the respective housings, the vacuum manifolds having associated therewith means for inducing a vacuum therein and hence, in the vacuum suction devices, the respective vacuum manifolds being also coupled to respective cylinders, the cylinders being arranged to slide the vacuum manifolds towards and away from the inner face of the housings, the vacuum suction devices being capable of engaging the opposing faces of a bag received between the housings when the vacuum manifolds are in a closed position adjacent the inner face of the housings.

19. The device for topping-off a substantially filled bag of claim 14 wherein the fill spout comprises a vertical auger bag filling machine.

20. The device for topping-off a substantially filled bag of claim 14 wherein the receiving platform comprises a conveyor.