NZ755261A - Pallet wrap monitoring apparatus - Google Patents

Abstract

A wrapping device for dispensing thin film comprising: a dispensing roll (22) from which thin film is dispensed, one or more stretching rollers (23) for stretching the film before it is applied, and a monitoring apparatus (1). The monitoring apparatus comprises a measuring roller assembly (2) arranged to contact the film between the dispensing roll and the stretching roller such that the measuring roller assembly turns when the film is dispensed as a result of such contact. The monitoring apparatus further comprises a measuring means (7) for determining the number of revolutions made by the measuring roller assembly; and a communication means for communicating the number of revolutions of the measuring roller to a data processing unit. The measuring roller assembly is configured to substantially contact an edge of the film (24) and rotate about an axis (26) perpendicular to the direction (25) the film is dispensed. The apparatus allows for monitoring of the amount of film dispensed by the thin film dispensing device to avoid over or under wrapping.

Description

PALLET WRAP RING APPARATUS The present invention relates to an apparatus for monitoring the use of film in a pallet wrapping e and to a method of wrapping pallets using such apparatus.

In recent times, it has become commonplace to load multiple units of a t onto a pallet for storage and ortation. The use of a pallet provides enhanced convenience for lifting and moving the multiple product units; for example, using a forklift truck. In order to locate and secure the multiple product units on the pallet, it has also become common to use plastic film, and, in particular, stretch film, to wrap products mounted on the . Machines are known in which the stretch film is supplied from a stationary mounted roll and the pallet spun to achieve the desired wrapping. Machines are also known in which the pallet to be wrapped is maintained stationary and the roll of stretch film is mounted to an arm or ring and the roll rotates around the same pallet in order to achieve the desired wrapping.

Problems have arisen in monitoring the amount of film being applied during each pallet wrapping operation. In ular, ors have a tendency to overwrap pallets, to achieve a perceived increased security of the wrapped items. In higher volume operations, the overuse of the stretch film can be a significant cost issue.

Equally, problems can arise if a pallet is under-wrapped, i.e. insufficient film is wrapped around the pallet to secure the items in place. Thus, it is important to be able to monitor, reliably, the amount of film that is being applied during a pallet wrapping operation.

One method of determining the amount of film applied to remove the stretch film after the application process and weigh this. Based on the known weight of the film to be applied it is then le to ate the length of film applied (or the number of times the pallet has been wrapped, if the size of the pallet is known). However, this is time consuming and es the pallet to be re wrapped. The inconvenience of this means it is rarely done by those responsible for pallet wrapping. ring arrangements have been proposed to assess the amount of film that is being dispensed during a pallet wrapping operation. For example, US Patent Application No. 2017/0101205 describes an tus for monitoring usage of stretch film on pallet wrap es. This patent describes a pallet wrap machine monitor in which a pair of rotary encoders are provided, the first engaging with unstretched film against a first idler roller, at a position prior to the film being taken up by a pre-stretch roller, and the second engaging with the stretched film against a gate idler, and data from the two rollers is used to assess the wrapping ion. It is difficult to retrofit such a monitoring apparatus to a pre-existing wrapping device as it requires sufficient accessible space around idler rollers (which may or may not exist). er, often the accessible rollers are motor driven, along with the pre-stretch rollers. A rotary encoder which engages a film against such a roller will not be capable of reliably determining if the film has broken, since if the film breaks, the rotary encoder will engage with the motor driven roller and ue to turn.

Thus, there remains the need for a reliable means of determining the amount of film being dispensed, especially where such means needs to be retrofitted, or at least to provide the public with a useful choice.

In a first aspect the present invention provides a wrapping device for dispensing thin film, the device comprising: a dispensing roll from which thin film is dispensed, one or more stretching rollers, for stretching the film before it is applied, and a monitoring apparatus sing: a measuring roller assembly arranged to contact the film between the dispensing roll and the stretching , or, where there is more than one stretching roller, the first stretching , such that when the film is dispensed the measuring roller assembly turns as a result of such contact; a measuring means for determining the number of revolutions made by the measuring roller assembly; and a communication means for communicating the number of tions of the measuring roller to a data processing unit, wherein the measuring roller assembly is configured to substantially contact an edge of the film and to rotate about an axis perpendicular to the direction the film is dispensed.

The measuring roller assembly can be configured such that the measuring roller rotates about an axis at right angles to an axis of rotation of the stretching roller.

The measuring roller ly may comprise a measuring part, and an extension part which, in use, is arranged to contact the film being dispensed. In certain embodiments the extension part is able to be removed from the measuring part.

The measuring roller assembly may be mounted for rotation in a base member, the base member being d on the wrapping , for example the housing of the ng device. Preferably the monitoring apparatus is able to be retro-fitted to the wrapping device.

It will be appreciated that the length of the measuring roller assembly can be varied, depending upon the arrangement of the wrapping device into which the monitoring apparatus is deployed. This is a particularly useful when applying the monitoring tus as a retrofit to an existing wrapping device. The ial length of the measuring roller can be varied without impacting upon the performance of the measuring part of the roller.

The measuring means may be a sensor or sensors, for example, an optical sensor, a magnetic sensor or an inductive sensor.

The ring apparatus may comprise an independent power supply, for e, a battery pack, so that its operation is independent of the wrapping device. Again, this is particularly useful when the monitoring tus is being retrofitted into an existing wrapping device, as there is no need to modify the operating system of the wrapping device to accommodate the monitoring apparatus.

In particular ments, the thin film is for application to transportable goods d on a pallet.

Further described herein is a monitoring apparatus for measuring the amount of film being applied by a wrapping device, the device comprising a dispensing roll from which thin film is dispensed, the device further comprising one or more stretching rollers, for stretching the film before it is applied to a load of transportable goods, and the monitoring apparatus comprising a measuring roller assembly configured to contact: (i) the hed film between the dispensing roll and the stretching roller, or, where there is more than one stretching , the first stretching roller, or (ii) the first stretching roller; such that when the film is dispensed the measuring roller assembly turns as a result of such contact; a measuring means for ining the number of revolutions made by the measuring roller ly; and a communication means for communicating the number of revolutions of the measuring roller assembly to a data processing unit, the data processing unit providing an output which allows assessment of the total film being dispensed.

In another aspect the invention provides a method of determining the amount of film being applied by a wrapping device sing a dispensing roll from which thin film is dispensed and one or more stretching rollers, for stretching the film before it is d to a load of ortable goods, the method comprising: contacting the film dispensed from the dispensing roll with a measuring roller assembly, wherein the measuring roller assembly substantially contacts an edge of the film and rotates about an axis dicular to the direction the film is dispensed as a result of said contact; measuring the number of rotations of the measuring roller assembly; and communicating the number of rotations to a data processing unit.

In an embodiment of this aspect the measuring roller assembly rotates about at axis at right angles to the axis of rotation of the stretching roller.

In certain embodiments of this aspect the measuring roller assembly has the features as described for the aspects above.

In certain embodiments of the above aspect, the steps of contacting, measuring and communicating are performed by a monitoring apparatus sing: the ing roller assembly; a measuring means for ining the number of revolutions made by the measuring roller assembly; and a ication means for communicating the number of revolutions of the measuring roller to a data processing unit.

In particular embodiments the monitoring apparatus has the features as provided for in the aspects above.

In certain embodiments of this aspect the transportable goods are mounted on a pallet.

In certain embodiments the data processing unit provides an output which provides an assessment of the amount of film dispensed.

Preferably the method is performed by a monitoring tus as described herein.

In order that the invention may be more readily understood, and so that the features thereof may be appreciated, an embodiment of the invention will now be described, by way of example, with reference to the accompanying drawings, in which: Figure 1 is a three-dimensional representation of a monitoring apparatus in accordance with the ion; Figure 2 is a three-dimensional representation, from a slightly different view, with a shorter measuring roller assembly led; Figure 3 illustrates the apparatus of Figure 1, with the roller in a vertical orientation; Figure 4 is a sectional view rating a part of the ring apparatus of Figure 3; and Figure 5 illustrates, in detail, a part of the apparatus illustrated in Figure 4.

Figure 6 illustrates a monitoring tus in accordance with the invention in use with a ng device. ing to the figures, and in particular to s 1, 2 and 3, a monitoring apparatus is generally indicated at 1. The apparatus 1 comprises a measuring roller assembly 2, which is rotatably mounted to a base sing a mounting platform 3 and a supporting ed mounting bracket 4. A support element 5 extends from the bracket 4 to support a power pack, for example a battery pack 6, and a sensor monitoring block 7.

Turning now to Figures 3, 4 and 5, the apparatus will be described in more detail.

The L-shaped mounting bracket 4 comprises a bottom bracket portion 8 and a perpendicular bracket arm 9 at one end thereof. Mounting apertures 10 are provided to facilitate secure location of the mounting bracket in an appropriate position on a wrapping device (not shown). r apertures may be provided in the bracket arm 9 to facilitate mounting of the monitoring roller in a different orientation, if necessary.

As best seen in Figures 3 and 4, the measuring roller assembly 2 comprises a measuring part 11 and an extension part 12. The extension part 12 can be supplied in any suitable length and can be selected ing upon the space available in the wrapping device in which the monitoring apparatus is to be mounted. The monitoring apparatus may be ed with a number of selectable extension s so that the length of the measuring roller assembly can be varied in dependence upon operating requirements.

Conveniently, the mounting t and roller assembly may be made from aluminium. However, other suitable materials may be used. The outer surface 12a of the ion part 12 may be treated with a suitable material to ensure that movement of film over the roller is accurately transmitted to move the roller itself, as will be explained r below, when operation of the monitoring apparatus is explained.

Referring now to Figures 4 and 5, it will be seen that the measuring part 11 of the measuring roller assembly 2 comprises a central ng port 13 to receive a mounting element 14 of the roller extension 12. Conveniently, the mounting t 14 is received in the mounting port 13 and located there by a screw arrangement.

However, any secure location arrangement will be acceptable.

The measuring part 11 of the measuring roller assembly 2 incorporates sensor elements 15. The sensor elements 15 are mounted in peripherally arranged mounting ls 16 so that the sensor elements will be presented around the circumference of the roller surface, but not project significantly therefrom. The sensor elements 15 cooperate with receptor ts 17 in sensor monitoring block 7, ating with a PCB unit 18 mounted in the block 7. The PCB unit 18 is connected with a data processing unit (not shown) in any suitable manner; for example, by wireless or bluetooth connection.

The measuring part 11 is mounted for rotation in the support platform 3 by an axle projection 19 which is supported for rotation within a roller bearing 19a which is secured in place by an internal circlip 20.

The selection of a sensor element 15 will depend upon the nment in which the monitoring device is to be installed. Suitable sensors include optical sensors, magnetic sensors and inductive sensors. Optical sensors, similar to those used in a standard computer mouse, can provide an accurate e of rotation, but may be susceptible to impaired mance if used in a high dust nment.

Magnetic sensors have been found to be particularly useful. In this arrangement, the sensor ts 15 would be s and the or elements 17 detect the changing magnetic field as the roller rotates and es this information to the data processing PCB’s 18.

As shown in figure 6, in use, the monitoring apparatus 1, in this case with a base of a different shape to that depicted in figures 1-5 is mounted in an orientation such that the measuring roller assembly 2 is located adjacent the unstretched film 21 at the position between the sing roller 22 and the first stretching roller 23. The measuring roller assembly 2 is positioned so that the film contacts the surface of the roller and the roller is thus rotated in dependence upon the output of film from the wrapping device. In particular the monitoring device is arranged so the measuring roller is perpendicular to the direction of the output of the film as (indicated by the arrow 25) and the axis of rotation is at right angles to the axis of rotation of the dispensing roller 22. The measuring roller thus substantially contacts the bottom edge of the film 24. As arranged, the measuring roller assembly 2 pushes the bottom edge of the film up slightly. This provides for a firmer and more reliable connection between the measuring roller assembly 2 and the film 21 without hampering the stretching of the film.

The nt of the film 21 causes the measuring roller assembly 2 to rotate in the direction of arrow 26. The sensors (not shown) measure the number of rotations of the measuring roller assembly and provides this information to the communication means (not .

The monitoring apparatus then transmits the data, preferably wirelessly to a data processing unit. Based on the number of rotations the data processing unit is then able to calculate the amount of film applied. The data processing unit may also be provided with information regarding the type of film (weight, material, etc) and cost, thereby ng the user to calculate the cost of each individual wrapping.

This arrangement provides a fairly simple, but highly reliable, indication of the film output which is capable of being retrofitted to a range of wrapping s.

It is clear that the monitoring apparatus is highly suitable for monitoring pallet wrapping devices and it will be appreciated that this simple, but highly efficient, monitoring unit could be applied to assess and monitor any other film dispensing arrangement.

In certain embodiments, a monitoring apparatus according to the invention could be installed to contact both the pre-stretched film, and the film after-stretching. This provides a e of the amount of stretching ng calibration of the machine.

In the present description of the invention and in the claims which follow, except where the context requires otherwise due to express language or necessary implication, the word “comprise” or variations such as “comprises” or “comprising” is used in an ive sense, i.e. to specify the presence of the stated feature but not to preclude the presence or on of further features in various embodiments of the invention. In addition, reference to an element by the indefinite article "a" or "an" does not exclude the possibility that more than one of the element is t, unless the context clearly requires that there be one and only one of the ts. The indefinite e "a" or "an" thus usually means "at least one".

It is to be understood that, if any prior art publication is referred to herein, such reference does not constitute an admission that the publication forms a part of the common general dge in the art, in New Zealand or any other country.

Claims (34)

What we claim is:

1. A wrapping device for dispensing thin film, the device comprising: a dispensing roll from which thin film is dispensed, one or more stretching rollers, for stretching the film before it is applied, and a monitoring apparatus comprising: a measuring roller assembly arranged to contact the film between the dispensing roll and the stretching roller, or, where there is more than one hing roller, the first stretching roller, such that when the film is dispensed the measuring roller assembly turns as a result of such contact; a measuring means for determining the number of tions made by the measuring roller assembly; and a communication means for communicating the number of revolutions of the ing roller to a data processing unit, wherein the measuring roller ly is configured to substantially contact an edge of the film and to rotate about an axis perpendicular to the direction the film is dispensed.

2. The ng device according to claim 1, wherein the measuring roller ly is configured to have an axis of rotation at right angles to an axis of rotation of the stretching roller.

3. The wrapping device according to any one of claims 1 or 2, wherein the measuring roller assembly comprises a measuring part, and an extension part which, in use, is arranged to contact the film being sed.

4. The wrapping device according to claim 3, wherein the extension part of the measuring roller assembly is able to be removed from the measuring part.

5. The wrapping device according to any one of claims 1 to 4, wherein the measuring roller assembly is mounted for rotation in a base member, the base member being d on the wrapping device.

6. The wrapping device according to claim 5, wherein the base member is mounted the housing of the wrapping device.

7. The wrapping device according to any one of claims 1 to 6, wherein the monitoring apparatus is able to be retro-fitted to the wrapping .

8. The wrapping device according to any one of claims 1 to 7, n the length of the ing roller ly can be varied, depending upon the ement of the wrapping device into which the apparatus is deployed.

9. The wrapping device according to any one of claims 1 to 8, wherein the measuring means comprises a sensor or sensors.

10. The wrapping device according to claim 9, wherein the sensor is an optical sensor, a magnetic sensor or an inductive sensor.

11. The wrapping device according to claim 10, wherein the sensor comprises one or more sensor elements and one or more receptor elements.

12. The wrapping device according to any one of claims 1 to 11, wherein the monitoring apparatus further ses an independent power supply.

13. The wrapping device according to claim 12, wherein the independent power supply is a battery pack.

14. The wrapping device of any one of claims 1 to 13, wherein the thin film is for application to transportable goods mounted on a pallet.

15. A method of determining the amount of film being applied by a wrapping device, the device comprising a dispensing roll from which thin film is dispensed, and one or more stretching rollers for stretching the film before it is applied to a load of transportable goods, the method comprising: contacting the film sed from the dispensing roll with a measuring roller assembly; wherein the measuring roller assembly substantially contacts an edge of the film and rotates about an axis perpendicular to the ion the film is dispensed as a result of said contact, measuring the number of rotations of the measuring roller assembly; and communicating the number of rotations to a data processing unit.

16. The method according to claim 15, wherein the ing roller rotates about an axis at right angles to the axis of rotation of the stretching roller.

17. A method according to claim 15 or 16, wherein the measuring roller assembly contacts the pre-stretched film between the dispensing roll and the hing roller, or, where there is more than one stretching roller, the first stretching roller.

18. The method according to any one of claims 15-17, wherein the measuring roller assembly comprises a measuring part, and an extension part arranged to contact the film being dispensed.

19. The method according to claim 18, n the extension part of the measuring roller assembly is able to be removed from the measuring part.

20. The method according to any one of claims 15 to 19, wherein the measuring roller assembly is d for rotation in a base member.

21. The method according to claim 20, n the base member is mounted to the ng device.

22. The method according to claim 21, wherein the base member is mounted to the housing of the wrapping device.

23. The method according to any one of claims 15 to 22, wherein the length of the measuring roller assembly can be varied, depending upon the arrangement of the wrapping device into which the monitoring apparatus is deployed.

24. The method ing to any one of claims 15 to 23, wherein the steps of contacting, measuring and communicating are performed by a monitoring tus comprising: the measuring roller assembly; a measuring means for determining the number of revolutions made by the measuring roller assembly; and a communication means for communicating the number of revolutions of the measuring roller to a data processing unit.

25. The method according to claim 24, n the measuring means comprises a sensor or sensors.

26. The method according to claim 25, wherein the sensor is an optical sensor, a magnetic sensor or an inductive .

27. The method according to claim 25 or 26, wherein the sensor comprises one or more sensor elements and one or more receptor elements.

28. The method according to any one of claims 24-27, wherein the monitoring apparatus further comprises an independent power supply.

29. The method according to claim 28, n the independent power supply is a battery pack.

30. The method according to any one of claims 24 to 28, wherein the monitoring apparatus is able to be retro-fitted to the wrapping device.

31. The method according to any one of claims 15 to 30, wherein the transportable goods are mounted on a pallet.

32. The method according to any one of claims 15 to 31, n the data processing unit provides an output which provides an assessment of the amount of film dispensed.

33. A monitoring tus substantially as herein described or exemplified, having reference to the anying drawings, which is used in a wrapping device according to any one of claims 1 to 14, or a method according to any one of claims 15-32.

34. A method according to claim 15, substantially as herein described or exemplified. 7 “ ' 5 :i DETAIL B FIG. 5