CA2921722C - Extendable chamber bulk bag and pallet box filler - Google Patents

Abstract

A bulk bag and pallet box filler having an in-feed gate, four synchronized rollers arranged in opposing parallel pairs, each wrapped in a wide belt that is led over the guide rollers to form an extendable chamber with flexible overlapping sides, which extends as the rollers unspool. The chamber's integrity is maintained by rings spaced along the exterior of the chamber. A gate closes or opens the bottom of the chamber, permitting produce to fill the pallet box or bulk bag. Extension and retraction of the chamber is controlled by sensors and a programmable logic controller. Fill height or weight in the bulk bag or pallet box is determined by proximity sensors or load cells. Hanging loop supports can be used to keep a tote bag in position while being filled. The filler fills bags or boxes with produce, such as potatoes, while minimizing bruising.

Description

EXTENDABLE CHAMBER BULK BAG AND PALLET BOX FILLER
[0001] TECHNICAL FIELD

[0002] The present invention generally relates to a bulk bag or pallet box filler. More particularly the invention relates to a device for filling large bulk bags or large pallet boxes with produce (such as but not limited to, potatoes, onions, carrots or round fruit) in a continuous flow all the way from an elevated in-feed conveyor down into the large bulk bag or pallet box in a gentle manner with minimal bruising or mechanical damage.

[0003] BACKGROUND

[0004] Large bulk bags are generally used to transport produce from the grower or packer to a processing facility where the produce may be re-bagged into smaller packages or the produce might further processed (for example, used in soups or prepared meals). These bulk bags commonly hold 1,000 to 1,200 kilograms of produce. Bulk bags may be interchangeably referred to herein as "tote bags".

[0005] Large pallet boxes are containers with rigid sides and are used to store produce or transfer produce and may hold from 1,000 to 1,400 kilograms.

[0006] Known bulk bag or pallet box fillers at various points in the filling process allow the produce to impact a hard surface with excessive force or be dropped with excessive force onto other produce, sometimes repeatedly. Potatoes dropped from a height of more than 20 centimeters onto a hard surface have the potential to bruise the potato or cause mechanical damage.

[0007] A machine commonly used to fill bulk bags uses a fall breaker system where produce entering the top of the chute falls down a series of slanted platforms until they reach the bottom of the chute.

[0008] Other machines use conveyors to lower the produce into the bulk bags or pallet box but at the end drop the produce into the conveyor from a height or at a speed which potentially damages the produce.

[0009] It is desirable to have a bulk bag or pallet box filler that allows produce to flow from an elevated conveyor down into a bulk bag or pallet box with minimal impacts on hard surfaces and less likelihood of bruising or mechanical damage.
SUMMARY
[0009.01] The present disclosure provides a bulk bag or pallet box filler comprising an extending flexible chamber comprised of four overlapping belts forming a square or rectangle with overlapping corners; rings on the exterior of the chamber deployed in pre-set intervals maintain the shape of the chamber and keep the corners overlapped; said chamber, being open at the top and enclosed at the bottom by a gate which can be opened or closed;
and sensors for measuring how far the chamber has extended downward, and to determine how close the chamber is to the bottom of the bulk bag or pallet box.
[0009.02] A process is described herein whereby a combination of sensors, programming, a programmable computer and an extending chamber facilitate the continuous flow of produce from an elevated conveyor down into a bulk bag or pallet box where the level of produce at the top of the chamber is maintained in a full or nearly full condition until the point where the bulk bag or pallet box are full.
BRIEF DESCRIPTION OF THE DRAWINGS
[0009.03] Embodiments of the present disclosure will now be described, by way of example only, with reference to the attached Figures.
[0009.04] Fig. 1 shows a front view of an embodiment of the bulk bag and pallet box filler.
[0009.05] Fig. 2 shows a side view of an embodiment of the bulk bag and pallet box filler.

[0009.06] Fig. 3 shows a top view of a roller layout of the bulk bag and pallet box filler of Fig. 1.
[0009.07] Fig. 4 shows a top view of a roller and belt layout of the bulk bag and pallet box filler of Fig. 2.
[0009.08] Fig. 5A shows a front view of an embodiment of the bulk bag and pallet box filler in operation, wherein produce flows from an in-feed conveyor. The fully retracted position is shown.
[0009.09] Fig. 5B shows a front view of an embodiment of the bulk bag and pallet box filler in operation, wherein produce flows past the in-feed gate.
[0009.10] Fig. 5C shows a front view of an embodiment of the bulk bag and pallet box filler in operation, wherein produce fills the chamber.
[0009.11] Fig. 5D shows a front view of an embodiment of the bulk bag and pallet box filler in operation, wherein the container is full of produce and is in the fully extended position.
[0009.12] Fig. 5E shows a front view of an embodiment of the bulk bag and pallet box filler in operation, wherein the bottom gate opens and upward movement allows produce to flow down.
[0009.13] Fig. 5F shows a front view of an embodiment of the bulk bag and pallet box filler in operation, wherein the in-feed conveyor stops when the bulk bag or pallet box is full.
[0009.14] Fig. 6A shows representative drawings of the front view of an embodiment of the bulk bag and pallet box filler.
[0009.15] Fig. 6B shows representative drawings of the side view of an embodiment of the bulk bag and pallet box filler.
DETAILED DESCRIPTION
[0010.01] The present disclosure provides a bulk bag or pallet box filler comprising an extending flexible chamber comprised of four overlapping belts forming a square or rectangle with overlapping corners; rings on the exterior of the chamber deployed in pre-set intervals maintain the shape of the chamber and keep the corners overlapped; said chamber, being open at the top and enclosed at the bottom by a gate which can be opened or closed;
and sensors for measuring how far the chamber has extended downward, and to determine how close the chamber is to the bottom of the bulk bag or pallet box. The filler may be referred to herein, interchangeably, as "the apparatus". The belts are of adequate width to herein be referred to interchangeably as "wide belts". Optionally, the bulk bag or pallet box filler can include a weigh scale to determine when the filler has filled the bulk bag or pallet box to a predetermined weight.
[0010.02] A
process is described which may employ the apparatus described herein. The process employs a combination of sensors, programming, a programmable computer and an extending chamber to facilitate the continuous flow of produce from an elevated conveyor down into a bulk bag or pallet box. The level of produce at the top of the chamber is maintained in a full, or nearly full, condition until the point where the bulk bag or pallet box is full of produce.
[0010.03] The bulk bag or pallet box filler may be configured such that each of the four belts comprising the four sides of the chamber are individually secured at the upper end and wrapped around a retaining roller which can be turned in one direction to shorten the chamber (lift it up) or turned in the other direction to lengthen the chamber (to make it descend).
[0010.04] The retaining rollers may comprise four rollers connected to each other at three of the corners with 1:1 ratio gears, thereby causing the retaining rollers to rotate at exactly the same speed. Thus, when one roller is turned by a motor, all four shafts of the retaining rollers will rotate at the same rate. The motor may be electrically, pneumatically or hydraulically powered.
[0010.05] Each of the four belts can be configured to pass over a guide roller, prior to the location at which they form the chamber. For example, two sets of two opposing guide rollers, where one set of opposing guide rollers is at the same elevation as the retaining rollers, and where the pair of opposing belts form the two outside panels of the chamber with the other set of opposing guide rollers being elevated above the first set of opposing guide rollers and these belts forming the inside panels of the chamber.

[0010.06] After passing over the guide rollers, each of the four corners of the chamber passes over a corner guide, which causes the belts at the corners of the chamber to overlap.
[0010.07] As the four belts extend downward, forming a chamber with overlapping corners, retaining rings are deployed at set intervals encompassing the circumference of the chamber, thereby keeping the corners overlapped and the chamber from expanding horizontally as it fills with produce. When in the full upright position, the retaining rings are held in place by a mechanism designed to release the rings at intervals along the chamber as it extends downward. The interval between rings is determined by straps fastened to the rings.
[0010.08] According to an embodiment of the bulk bag or pallet box filler described herein, each bottom end of the four sides is attached to one side each of a square frame supporting the bottom gate at the bottom of the chamber. When in the closed position, the bottom gate keeps produce from flowing out of the chamber. The bottom gate may be moved between the open position and the closed position in a controlled manner by an actuator; the actuator optionally being pneumatic or electric.
[0010.09] A proximity sensor may be positioned above the chamber, which may be connected to a programmable logic computer (PLC). The proximity sensor may be used to determine when produce entering the top of chamber has reached a predetermined height, causing the retaining rollers to spool or unspool the wide belts by a predetermined amount, thereby lowering or raising a chute.
[0010.10] Produce flowing into the chamber of the filler may first encounter a downward sloping entry chute, wherein the downward slope of the entry chute deflects the produce thereby minimizing the impact force as the produce proceeds into the chamber. The entry chute may be referred to herein interchangeably as an "in-feed chute".

[0010.11] The flow of produce first entering the entry chute may be interrupted by a closed, padded in-feed gate. The purpose of the in-feed gate is to minimize the initial fall height of produce entering the filler, by confining the initial inflow to the in-feed chute until the overhead sensor detects the produce in the entry chute has reached a predetermined height at which point the in-feed gate is raised in a controlled manner, thereby allowing the produce to continue on into the chamber. The "overhead sensor" may be referred to interchangeably herein as an "upper sensor".
[0010.12] The lengthening (downward movement) of the chamber can be determined by the amount of produce in the chamber, as monitored via the proximity sensor positioned above the entry chute and chamber. When the level of the produce has reached a predetermined height, the PLC can cause the belts to unspool a limited and predetermined length and thus lengthens (lowers) the chamber, creating space for more produce to enter the top of the chamber.
As more produce enters the top of the chamber and the produce again reaches a predetermined level, the PLC once more causes the chamber to lower a predetermined amount again creating more room for produce to enter the top of the chamber. This cycle may continue until the chamber has descended to within a predetermined length from the bottom of the bulk bag or pallet box. The rate of descent of the chamber can be determined by how quickly produce enters the top of the chamber and how full the top of the chamber is.
[0010.13] Once the chamber has descended to within a predetermined length from the bottom of the bulk bag or pallet box, the PLC can activate a switch opening a valve on an air cylinder attached to the bottom gate, causing the bottom gate to open in a controlled fashion.
This allows produce to flow down through the chamber and into the bulk bag or pallet box situated there. The outward flow can stop when the level of produce in the bulk bag or pallet box stabilizes and arrests the downward flow. The outflow of produce creates more space at the top of the chamber, leaving room for more produce to enter.

[0010.14] The predetermined length from the bottom of the bulk bag or pallet box can be determined by either counting revolutions of the retaining rollers starting from the full up position, or by a proximity sensor mounted on the side of the gate.
[0010.15] When the chamber reaches the predetermined level from the bottom of the bulk bag or pallet box and the bottom gate is opened, once the level of produce at the top of the chamber again reaches a predetermined level the PLC can cause the retaining rollers to rotate in a reverse direction causing the belts to wrap around the retaining rollers thereby shortening the chamber (raising it) by a predetermined length. The upward movement of the chamber allows a limited amount of produce to flow down the chamber into the bulk bag or pallet box, thereby creating more room at the top of the chamber. As more produce flows into the chamber and it again reaches a predetermined height, the chamber is again raised by a predetermined length. This cycle can continue until the chamber has reached a predetermined height or until an input from a weigh scale indicates that the produce in the bulk bag (or pallet box) has reached a predetermined weight. The rate of ascent (retraction) of the chamber can be, at all times, determined by the rate of flow of produce into the top of the chamber, and/or by the height of the produce in the chamber.
[0010.16] Once the level of produce inside the bulk bag (or pallet box) has reached a predetermined height or predetermined target weight, the PLC can cause five actions to occur.
First, the in-feed conveyor may be stopped for a short predetermined length of time; second, the in-feed gate can be lowered; third, as the in-feed gate is being lowered the belts forming the walls of the chamber may be quickly retracted and the chamber raised to its full up position;
fourth, the bottom gate can be closed; and fifth (lastly) when all these actions have occurred the in-feed conveyor may be restarted, at which point the bulk bag filler is ready to repeat the entire cycle for filling a new (empty) bulk bag or pallet box.
[0010.17] Having completed these five actions, the produce can continue to flow into the apparatus until the chamber has descended by a predetermined length, at which point (or before which point) the operator may confirm to the PLC by activating a switch or control button that a new bag or box has been put in position. In this embodiment, if the operator does not confirm a new bulk bag or pallet box has been put in place, the in-feed conveyor will be stopped and the chamber will stop its downward motion. Thus, in this embodiment the filling operation would not continue until the operator confirms to the PLC the new bulk bag or pallet box has been put in place.
[0010.18] The bulk bag or pallet box filler may additionally comprising a built-in buffering hopper. When the filler has completed filling a bulk bag or pallet box and has cycled back to the start position, the filler can continue to accept new produce even before the new bulk bag or pallet box has been placed beneath the chamber. Thus, the chamber may continue to fill and descend up to a predetermined length which may be calculated to be just above the height of an empty bulk bag (or pallet box), at which point the operator can push a button or remote control connected to the PLC confirming an empty bulk bag or pallet box has been placed underneath the chamber to keep the filler operating. A person operating the apparatus may push a button or remote control connected to the PLC, confirming an empty bulk bag or pallet box has been placed underneath the chamber to keep the filler operating. However, if it is not confirmed that an empty container has been placed under the chamber, then the PLC may cause the in-feed conveyor to stop, and thus the chamber can stop its downward motion.
[0011] THE APPARATUS: The filler includes a padded in-feed chute (1), a padded in-feed gate (2) and an extendable chamber with flexible sides formed of wide belts (7) which also has a padded bottom gate (10) at the bottom. The sides of the chamber are formed by wide belts (7) connected to an arrangement of retaining rollers (4), lower guide rollers (5), upper guide rollers (6), and a corner guide (23) at the top of the chamber. An upper sensor (3) disposed above the in-feed chute (1) monitors the height of the produce in the in-feed chute and the chamber. The in-feed gate (2) has been constructed such that is does not interfere with the upper sensor (3). A lower sensor (11) mounted at near the bottom of the chamber at the side of the bottom gate (10) detects how close the extending chamber comes to the bottom of the bulk bag or pallet box. The chamber is extended downward as it fills with produce and then slowly retracted back up again as the produce is transferred to into the bulk bag or pallet box, as depicted in Fig. 5A to Fig. 5F. Optionally, the lower sensor (11) may be attached to a square frame (9) located below the retaining rings, which support the bottom gate of the chamber.
[0011.1] Retaining rings (8) spaced at intervals along the chamber keep its shape as it extends. The downward extension and upward retraction of the chamber is determined by how fast produce enters the chamber and by the level of produce in the chamber.
How far the chamber travels downward is determined by either counting revolutions of the retaining rollers (4) or by the proximity to the lower sensor (11) mounted near the bottom gate

(10). A pallet box, or a large tote bag or bulk bag (16) is positioned below the filler.
Hanging bars (12) are included on which to suspend the bulk bag (16). A magazine (18) is provided to store up to 24 empty bulk bags for east access to replace full bulk bags which have been removed.
[0011.2] A PLC (programmable logic computer) monitors and controls the operation of the filler. There are controls which the operator uses to initiate filling a new bag or pallet box, for stopping the filler, for setting target weights or heights, for causing the filler to pause its operation and for resetting the filler. Load cells (15), shown in Fig. 1 and Fig. 2, are positioned under the filler to measure the combined weight of the filler, pallet (13), bulk bag (16) or pallet box and any produce in the chamber. The load cells (15) provide input to the PLC which determines when the produce in the bulk bag or pallet box has reached a preset target weight.
A plate (14), as shown in Fig. 1 and Fig. 2, supports the pallet (13) for the bulk bag (16) or pallet box. A support frame (17) supports the chamber and in-feed chute (1) above the bulk bag or pallet box.
[0012] Advantageously, the use of the apparatus allows the produce to flow from an elevated position down into a large container with minimal or no impact with hard surfaces, for the entire filling process, thereby limiting opportunities for mechanical damage or bruising of the produce.
[0013] When the filler begins operation, produce flowing in from an in-feed conveyor enters the in-feed chute (1), as depicted in Fig. 5A. The in-feed chute is angled downward so that produce comes in at an acute angle to minimize the impact force. Optional padding on the bottom of the in-feed chute can further dampen the forces exerted on the produce entering the filler.
[0013.1] Near the bottom of the in-feed chute, the initial flow of produce is arrested by a padded in-feed gate (2) as shown in Fig. 5A, which has rotated downward to block entry to the chamber. The short travel distance experienced by the initial produce entering the in-feed chute (1) prevents the produce from reaching a velocity where bruising can occur if an incoming item of produce strikes another surface or another item of produce.
[0013.2] A proximity sensor, depicted in Fig. 5A as upper sensor (3), is positioned above the chamber to measure the height of the produce in the in-feed chute and the chamber. When the produce has reached a pre-determined height the PLC activates an actuator (the actuator can be either pneumatic or electric) which causes the in-feed gate to rise and the flow of produce continues down the in-feed chute and into the flexible extendable chamber which has a closed bottom gate at the bottom of the chamber. For the initial inflow of produce, the chamber will be in its fully retracted position as illustrated in Fig. 5A.
[0014] The flexible extendable chamber is comprised of four wide belts (7) on rollers arranged so that as they unspool they form a generally rectangular or square chamber with overlapping corners, as shown in Fig. 4. At the upper terminal end, each belt (7) is attached to a retaining roller (4), which when rotated one way winds up the belt (7) and thereby shortens (raises) the chamber and which rotated the other way allows the belt to unspool, thereby extending (lowering) the chamber. The retaining rollers (4) of the four belts (7) comprising the chamber are arranged in opposing pairs as depicted in Fig. 3 and Fig. 4, and are connected via gears (21) having a 1:1 ratio, located at three of the corners (as shown in Fig. 3). Thus, when one of the shafts is turned all of the shafts turn at the same rate, thereby lowering or raising each of the four sides (the belts) of the chamber synchronously. The retaining rollers (4) are also supported by a bearing (22) at the fourth corner, as depicted in Fig. 3. A
motor (20), attached to any one of the gears (21) at the three corners, rotates the shafts.

[0015] As can be seen in Fig. 1, from the lower retaining rollers (4) the belts (7) that form the flexible sides of the chamber pass over lower guide rollers (5) and upper guide rollers (6) and then extend downward. Two opposing lower guide rollers (5) are arranged parallel to each other at approximately the same level as the retaining rollers (4). The two opposing upper guide rollers (6) are elevated above the first pair of retaining rollers (4).
The belts (7) which pass over the lower guide rollers (5) will overlap on the outside of the corners of the chamber while the belts (7) which pass over the upper guide rollers will overlap the corners on the inside of the chamber. As shown in Fig. 3, the lower and upper guide rollers (5, 6) are arranged in a square or rectangle configuration.
[0016] As seen in Fig. 3 and Fig. 4, as the four belts (7) extend downward they pass through a corner guide (23) which causes the belts to overlap at the corners and so form the shape of the chamber.
[0017] The chamber retains its shape and integrity via retaining rings (8) encircling the outside of the chamber deployed at intervals along the chamber, as seen in Fig. 1 and Fig. 2, as the flexible sides formed of the belts (7) extend downwardly. When the chamber is fully retracted in its start position the retaining rings (8) are gathered at the top and may be held in place by a mechanism which causes the rings to deploy in a specific order. The spacing of the rings is determined by straps (24) on each side of the chamber. The retaining rings (8) are fastened to the belts (7) at consistent and fixed intervals.
[0018] The bottom of the chamber is enclosed by .a padded bottom gate (10) at the bottom of the chamber, retaining produce in the chamber while it the bottom gate (10) is in the up position or while the chamber is extending downward.
[0019] As produce flows into the chamber, an upper sensor (3) positioned above the chamber measures when the produce reaches a predetermined height (calculating when the chamber is full), at which point the PLC instructs the motor (20) attached to the retaining rollers

- 11 -to unroll the belts in a synchronous fashion for a predetermined time interval or a predetermined number of revolutions, thereby lengthening the chamber and creating some space at the top of the chamber to accommodate more produce.
[0020] The predetermined time or number of revolutions are generally set so that the chamber moves up or down in increments of less than 10 centimeters so additional produce entering the top of the chamber from the in-feed chute doesn't fall more than 10 to 15 cm onto the produce already in the chamber. Falls of more than 20 cm have the potential to bruise the produce.
[0021] Positioned below the chamber is an empty bulk bag suspended on bulk bag hangers (also referred to herein as "hanging bars"), or an empty pallet box.
Before the chamber has extended by a predetermined distance above where the top of the hanging bulk bag would be, the filler operator can push a control button, or a remote control device communicating with the PLC, confirming that an empty bulk bag or empty pallet box is in place below the chamber.
If the PLC does not receive this confirmation it can stop the in-feed conveyor and thus stop the chamber from descending further. If the button is pushed the filler will continue operation.
[0022] When sensors indicate produce flowing into the top of the chamber has filled the chamber again, the chamber is then extended a predetermined distance again, leaving more room for produce to flow into the top via the in-feed chute. When it fills again, the chamber extends downward again for a predetermined distance and this cycle continues (as illustrated in Fig. 5A to Fig. 5C) for as long as produce continues to flow into the top of chamber or until the chamber extends to within a predetermined distance from the bottom of the bulk bag or pallet box. How quickly the chamber descends can be determined by how fast the produce entering the chamber keeps filling the top.
[0023] When the chamber has extended to the point that it reaches the bottom of the bulk bag or pallet box, the bottom gate at the bottom of the chamber is opened in a controlled

- 12 -manner allowing some produce to flow down through the chute and out into the container (Fig.
5D), this creates space at the top of the chamber for more produce.
[0024] Having reached the bottom of the bulk bag or pallet box and having opened the bottom gate and when the chamber has been filled again, the PCL reverses the direction of the chamber's movement and causes it to retract (raise) a predetermined distance.
[0025] The upward movement allows some amount of produce to flow down and out of the chamber creating space for more produce at the top (Fig. 5E). An operator may control approximately how much produce flows out of the chamber in the upward cycle at each interval by altering the predetermined height the chamber is raised at each interval.
Produce will flow down and out of the chute until the flow backs up and stops the downward flow.
[0026] When sensors indicate the chamber is full again the it is retracted a predetermined distance again allowing more produce to flow down and out of the chute, creating more room at the top for more produce to enter the filler and this cycle continues until the bulk bag or pallet box are filled to a predetermined height or until the bulk bag or pallet box achieve a predetermined weight; at this point the PLC determines that the bulk bag or pallet box is full.
[0027] When the bulk bag or pallet box is full, a series of events occurs;
first the in-feed conveyor is stopped and the in-feed gate (2) is closed (Fig. 5F). When the in-feed gate closes, the in-feed conveyor is restarted. While this is happening the chamber is quickly retracted to its start position and the bottom gate is closed (Fig. 5F).
[0028] If another container (bulk bag or pallet box) needs to be filled, the in-feed chute and extending chamber will act as a buffer hopper and will continue to fill while the full bulk bag or pallet box is taken away and an empty container is put in place.

- 13 -[0029] The filler will operate until it reaches a point above where an empty bulk bag would be hung, at which point the in-feed conveyor will be stopped and the filler stops the descent of the chamber unless an operator pushes the button to instruct the PCL that a new empty container has been put in place. If the button is pushed, the filler will continue to fill the container.
[0030] Fig. 6A and Fig 6B show representative drawings of the front view and side view, respectively, of an embodiment of the bulk bag and pallet box filler similar to that depicted in Fig. 1 and Fig. 2.

- 14 -

Claims (21)

CLAIMS:

1. A bulk bag or pallet box filler, comprising:
an extendable flexible chamber comprising four overlapping belts forming four walls of the chamber in a square or rectangular shape, wherein the belts are configured to overlap at the corners of the square or rectangular shape; the chamber having a top, a bottom, an interior, an exterior, and a length; wherein the chamber is open at the top, and is enclosed at the bottom by a bottom gate which can be opened or closed, said chamber being extendable between an unextended position and a fully extended position;
retaining rings on the exterior of the chamber disposed at pre-set intervals, wherein said retaining rings maintain the shape of the chamber and keep the belts overlapped at the corners, four retaining rollers at the top of the chamber, configured in the square or rectangular shape of the chamber, wherein each of the four belts comprising the four walls of the chamber comprises an upper end and a lower end, and at the upper end each belt is secured to and wrapped around one of the retaining rollers, wherein the retaining rollers can be rotated in one direction to shorten the length of the chamber to the unextended position, or rotated in the other direction to extend the length of the chamber to the fully extended position;
an upper sensor for determining how far the chamber has extended; and a lower sensor to determine how close the bottom of the chamber is to the bottom of the bulk bag or pallet box.

2. The bulk bag or pallet box filler of claim 1, additionally comprising:
gears connecting the retaining rollers to eachother at three corners of the square or rectangular shape, said gears having a 1:1 ratio; and a motor for rotating at least one of the retaining rollers;
wherein rotation of one of the retaining rollers causes each retaining roller to rotate at the same rate.

3. The bulk bag or pallet box filler of claim 2, wherein the motor is electrically, pneumatically or hydraulically powered.

4. The bulk bag or pallet box filler of any one of claims 1 to 3, additionally comprising two pairs of opposing guide rollers, each guide roller being adjacent one of the retaining rollers, wherein each of the four belts passes over a guide roller prior to forming the wall of the chamber;
wherein one pair of opposing guide rollers is located at the same vertical elevation as the retaining rollers, and the other pair of opposing guide rollers is located at a higher vertical elevation than the retaining rollers.

5. The bulk bag or pallet box filler of claim 4, wherein the two belts passing over the higher guide rollers overlap the other two belts at the corners of the square or rectangular shape to the interior of the chamber.

6. The bulk bag or pallet box filler of claim 4 or 5, additionally comprising four corner guides adjacent the guide rollers, wherein, after passing over the guide roller, each of the four belts passes over one of the corner guides to guide the belts into the overlap configuration at the corners of the square or rectangular shape.

7. The bulk bag or pallet box filler of any one of claims 1 to 6, additionally comprising straps fastened to the retaining rings at intervals along the extendable flexible chamber;
wherein as the length of the chamber extends, the retaining rings are deployed at set intervals around the exterior of the chamber; said retaining rings being configured to keep the corners of the chamber overlapped, and to prevent the chamber from expanding horizontally as it fills with produce, wherein the interval between rings is determined by the length of the straps.

8. The bulk bag or pallet box filler of claim 7, additionally comprising a retaining mechanism for holding the retaining rings in place in a full upright position when the chamber is in an unextended position.

9. The bulk bag or pallet box filler of any one of claims 1 to 8, additionally comprising a square or rectangular frame on the exterior of the chamber, wherein the frame is attached at each lower end of the four belts comprising the four walls of the chamber, and the frame supports the bottom gate.

10. The bulk bag or pallet box filler of claim 9, additionally comprising an actuator for opening and closing the bottom gate.

11. The bulk bag or pallet box filler of claim 10, wherein the actuator is pneumatic or electric.

12. The bulk bag or pallet box filler of claim 10 or 11, additionally comprising an activating switch for activating the actuator to open the bottom gate when the chamber has descended to within a predetermined length from the bottom of the bulk bag or pallet box thereby permitting flow of produce through the chamber and into the bulk bag or pallet box.

13. The bulk bag or pallet box filler of any one of claims 1 to 12, additionally comprising a programmable logic computer, wherein the upper sensor provides measurements of how far the chamber has extended to the programmable logic computer for determining when produce entering the top of chamber has reached a predetermined height for causing the retaining rollers to rotate in a direction to spool or unspool the belts so as to shorten or extend the length of the chamber by a predetermined amount.

14. The bulk bag or pallet box filler of claim 13, wherein the lower sensor provides measurements of the lengthening of the chamber to the programmable logic computer, for the chamber to descended to within a predetermined length from the bottom of the bulk bag or pallet box to be filled.

15. The bulk bag or pallet box filler of any one of claims 1 to 14, additionally comprising a weigh scale to determine when the filler has filled the bulk bag or pallet box to a predetermined weight.

16. The bulk bag or pallet box filler of claim 15, wherein the weigh scale comprises a plate disposed beneath the chamber for placement of the bulk bag or pallet box thereupon, and load cells beneath the plate for sensing the weight of the produce in the bulk bag or pallet box.

17. The bulk bag or pallet box filler of any one of claims 1 to 16, additionally comprising a downward sloping in-feed chute for directing a flow of produce into the chamber.

18. The bulk bag or pallet box filler of claim 17, additionally comprising an in-feed gate located along the in-feed chute, said in-feed gate being movable between an opened position and a closed position for controlling the flow of produce along the in-feed chute and into the chamber.

19. The bulk bag or pallet box filler of claim 18, wherein the in-feed gate is padded.

20. The bulk bag or pallet box filler of claim 18 or 19, wherein the in-feed gate opens or closes based on measurements provided by the upper sensor detecting when the produce in the chamber has reached a predetermined height.

21. The bulk bag or pallet box filler of any one of claims 17 to 20, additionally comprising a buffering hopper for receiving and holding produce from the in-feed chute when a filled bulk bag or pallet box is being replaced beneath the chamber by an empty bulk bag or pallet box, wherein produce held in the buffering hopper is released to the chamber when the empty bulk bag or pallet box is in place beneath the chamber.