WO2010089584A1

WO2010089584A1 - Wound roll as well as control of a machine fed from such a roll

Info

Publication number: WO2010089584A1
Application number: PCT/GB2010/050130
Authority: WO
Inventors: Trevor Davey; John Townsend
Original assignee: Easypack Limited
Priority date: 2009-02-03
Filing date: 2010-01-28
Publication date: 2010-08-12
Also published as: GB201111064D0; GB0918133D0; GB2467399A

Abstract

A roll (12) includes a core (40) to which a metal shim (42) is attached. When material is being unwound from the core the metal shim (42) induces a signal in an inductive device (52) within a roll holder tube (50). The induced signal allows the machine to continue to operate. If the induced signal is not detected operation of the machine ceases.

Description

WOUND ROLL AS WELL AS CONTROL OF A MACHINE FED FROM SUCH A ROLL

The present invention relates to a hollow wound roll, a machine arranged to process material coming off a wound roll and a method of operating a machine to process material coming off a hollow wound roll. The present invention is particularly but not exclusively applicable to wound rolls for use in manufacturing dunnage.

WO95/31296 discloses a packaging making machine, in which:

Figure 1 is a plan view of a dunnage forming machine;

Figure 2 is a side view of Figure 1 ;

Figure 3 is an end view of Figure 1 ;

Figure 4 is a cross-section through the line 4-4 of Figure 1 showing the form that paper takes up at that stage;

Figure 5 is a cross-section through the line 5-5 of Figure 1 showing the form that the paper takes up at that stage;

Figure 6 is a cross-section through the line 6-6 of Figure 1 showing the form that the paper takes up at that stage;

Figure 7 is a cross-section through the line 7-7 of Figure 1 showing the form that the paper takes up at that stage; and

Figure 8 is a close up view of the central part of the paper in Figure 7.

As shown in Figures 1 and 2, paper 10 is fed from a single multiply roll 12 of paper or, alternatively and not shown, from three separate paper rolls or, alternatively and not shown one roll of single ply. The paper 10 passes between an upper flat tapering wall 14 and a lower flat inwardly tapering former 16. The sides of the former 16 are each defined by an arcuate wall 18 that extends through approximately 180°.

The paper is pulled off the roll 12 by two pairs of spaced rear rubber nip rollers 2OA and a forward pair of rubber nip rollers 2OB. The lower nip rollers are driven and the upper idler nip rollers are urged, by the weight of the wall 14 or by springs (not shown) towards the lower rollers to trap the paper 10 between the pairs of rollers. The wall 14 and the former 16 have openings 22 to allow the upper nip rollers to contact the paper. The wall 14 starts near the rollers 2OA to allow the free end of paper, on start up, to be fed directly into the rollers 2OA. If desired, the rollers 2OB can be omitted.

At the ends of the former 16 the paper passes through a pair of meshing gear wheels 24. The gears are spring biased towards each other. The lower wheel is driven. The action of the gear wheels 24 deforms the surfaces of the paper that pass between them to hold the dunnage together loosely. The paper may be held in the position shown in Figures 7 and 8 as the gear wheels displace the cellulose fibres in adjacent layers to cause the fibres to interact. Alternatively or additionally the folds made in the paper by the gear wheels may be sufficient to connect the layers together.

The driven rollers and the driven gear wheel are drivably connected by a belt or chain 26. As the diameter of the driven roller is greater than the diameter of the gear wheel the surface of the roller travels at a greater speed than the gear wheel thereby causing the paper to be pushed into the gear wheels rather than the gear wheels pulling the paper through. The ratio between the driven roller and gear wheel is determined to feed paper at a slightly greater rate than the gear wheel could on its own. That ratio may be 1.07: 1.0. This assists in the bunching up of the paper and therefore in increasing the bulk of the dunnage. As the gear wheels are spring loaded towards each other they can move apart occasionally, if required, to allow the paper to be pushed through. A motor 38, shown schematically, drives the gear 24 and then the lower roller 2OB by the belt 26.

Immediately after the gear wheels a pair of blades 33A and 33B are provided to cut the dunnage at the required length. The operation of these knives can be manual or automatic and is described later.

As the central part of the paper is under tension as it approaches the rubber rollers, and as the base of the former is flat, the edges 28 of the paper roll over in a controlled manner and around as shown progressively in Figures 4 to 6. When the paper is pushed into the gear wheels the rolls of paper from each side contact each other before being crushed in the central region 30 where multi layers, for instance eight, are connected leaving roughly oval shapes 32 at each side. It will be appreciated that the shape of the cross-section of the paper, particularly at the later stages, is shown schematically. The blades 33A and 33B are each arranged to cooperate with an anvil plate 34. Each blade is connected to an associated cog 35A and 35B and is able to partially rotate when a chain 36 is pulled to cause one of the blades 35A to pass against the anvil plate 34 cut over half of the width of the dunnage and subsequently one of the blades 35B to cut the remainder of the dunnage.

As each blade does not pass through the whole of the width of dunnage the momentum of the blades is able to carry the blades through their reduced cutting stroke with less force or torque than would be required with a single blade that had to pass through the complete width.

The blades are encouraged to maintain a cutting action against the anvil by applying a small bending force at both ends of the anvil via jacking screws 37, as shown in Figure 1. Furthermore as two blades extend from diametrically opposite parts of each cog the dunnage is able to be cut through upon a 180° rotation of the cogs, and the cutting life of the apparatus is more than doubled compared to the life with a single blade.

When the paper roll runs out it is important to stop the machine as soon as possible in order to prevent boxes that should be filled automatically not being so filled and in order to prevent cooperating rollers and gears from contacting each other thereby damaging each other. To achieve the stoppage a lever 60 is biased against the paper web by a spring 62. When the paper roll runs out the spring biases the lever towards a switch 64, as shown in dash lines. When the lever hits the switch the machine is stopped.

A problem with such a lever and switch mechanism is that the paper has to be passed around the lever before feeding the paper through the machine. In addition the spring has to be precisely chosen in order that it is not too weak or too strong. Further, different springs may be required for different strengths or weights of paper. Furthermore, should the paper coming off the roll go slack during the operation then the switch may be inadvertently operated.

According to one aspect of the present invention, a hollow wound roll includes, at an inner region, a metal portion at at least one extent along the axis of rotation of the roll which metal portion only extends part of the way around the axis whereby, in use, rotation of the roll and thereby the metal portion is arranged to induce a signal in an inductive device cooperating with the metal portion whereby monitoring means are arranged to monitor the signal and cause a machine that has been fed from the roll to stop when a predetermined event for the signal occurs.

The metal portion may be located at a middle region along the axis of rotation of the roll. The roll may include a core on which the roll is wound and the metal portion may be attached to the core for instance by an adhesive member. The roll may comprise a wound paper roll. The predetermined event may be arranged to be cessation of the signal. The predetermined event may be a reduction in the signal. The predetermined event may be a specific value for the signal.

According to another aspect of the present invention a machine is arranged, in use, to process material being fed from a hollow wound roll which roll includes a metal portion at at least one extent along the axis of rotation of the roll which metal portion only extends part of the way around the axis, the machine including a stationary conductor arranged to cooperate with the metal portion whereby, in use, rotation of the roll and thereby its metal portion induces a signal in the conductor, the machine including monitoring means arranged to monitor the induced signal and thereby cause the machine to stop when a predetermined event for the signal occurs.

The machine may be arranged to be stopped before the trailing edge of the roll leaves an output of the machine and may be arranged to be stopped before the trailing edge of the roll reaches an output of the machine. The machine may be arranged to be stopped before the trailing edge of the roll reaches an input to the machine.

The conductor may be coextensive with the conductor along the axis of the roll.

The machine may comprise a dunnage making machine.

According to a further aspect of the present invention a method of monitoring a machine being fed from a hollow wound roll comprises inducing a signal caused by a metal portion on the roll rotating around a conductor as the roll rotates during unwinding of the roll, the method comprising stopping the machine when a predetermined event for the signal occurs.

The predetermined event may comprise stopping the machine when the signal stops being generated. The predetermined extent may comprise stopping the machine when there is a reduction in the signal. The predetermined extent may comprise stopping the machine when the signal reaches a specific value.

If the paper that is fed from the roll 12 is not of the correct grade or is not of a consistent grade throughout the roll then any one of a number of problems could arise. For instance, the paper may jam in the gear wheels 24 or the cellulose fibres in adjacent layers may not be caused to interact by the gear wheels or may not interact to a sufficient extent. Alternatively or additionally the paper may not take up the current shape for the dunnage as it passes through the former. Furthermore, parts packed with poor quality dunnage may become damaged during transit.

It is an object of the present invention to attempt to overcome at least one of the above or other disadvantages. The present invention is defined in the claims and elsewhere in the specification. The invention may comprise any combination of the claims or other features.

The present invention can be carried into practice in various ways but one embodiment will now be described by way of example and with reference to the accompanying drawings, in which:

Figure 9 is a perspective view of a paper supply roll 12, and

Figure 10 is a perspective view of a roll holder tube 50 fixed to the machine.

The roll 12 may be a single ply winding or a multiple ply winding which is wound around the core 8 and which is used to supply the dunnage making machine in WO95/31296. It will be appreciated that the roll 12 may be arranged to supply any other machine including other dunnage making machines.

Some users will often fit rolls which do not meet the requirements of the machine. To ensure that sub standard rolls are not used the roll is wound around the core 8 which is fitted with a metal portion spaced from the axis and extending partially around the axis preferably along a part of the axis that is coextensive with the extent of the roll. The metal portion may comprise a steel shim 42, preferably in a central region or in the centre. The steel shim is held in place by an adhesive label 44 shown in Figure 9. The shim 42 may be mounted on the inside of the hollow core 8 or in an opening through the hollow core or, as shown, on the outside of the core.

In use, as paper is being withdrawn from the roll, the core is caused to rotate. This causes the shim 42 to rotate about the roll holder tube 50. An inductive device 52 is mounted on the inside of the tube 50. Consequently the rotation of the shim induces a signal which is sent to a control 48 of the machine via a conductor 46

The control 48 can operate in a number of different ways. One operational mode is for the control to receive a signal indicating that rotation of the roll has commenced, for instance by detecting that the nip rollers 2OA or 2OB are being driven or that the gear wheels 24 are being driven. The signal from the rollers or wheels works in a similar manner to the signal from the roll holder tube 50. The control 48 then expects to receive a signal from the device 52 that has been induced by rotation of the shim in the core 40.

If the induced signal is received the machine continues to operate as previously described. If the induced signal is not received then the machine can cause the drum to the nip rolls or the gears or both to stop or alternatively or additionally may prevent the roll from being able to rotate.

Stoppage may occur after a predetermined period of time. Alternatively, stoppage may occur after a predetermined length of paper has been withdrawn from the roll such as, for example 2m, which may be circumference of a new roll. The length can be measured by the number of rotations of the nip rollers, for instance.

The machine may be arranged to stop completely or for a predetermined period of time. The control may be provided with a reset switch whereby, after stoppage, normal operation of the machine can take place again. The control may include a delay factor whereby the reset cannot be operated until a predetermined period of time has elapsed such as 10 seconds, for instance.

With a roll as described in relation to Figures 9 and 10 only rolls which have the shim 42 can be used. Consequently the roll can be wound with the correct grade or grades of paper which ensures that the required quality of dunnage is produced and which ensures that the paper does not cause the machine to jam and which ensures safe transit of articles being protected by the dunnage.

When the roll runs out the roll stops rotating and thus the control 48 will no longer receive a signal from the device whilst still receiving a signal from rollers or wheels. At that time the machine can be stopped. Stopping may be immediate or may be after a predetermined period of time. Preferably stoppage occurs before the trailing end of the paper exits the machine, or reaches the meshing gear wheels 24 or reaches the drive from the paper comprising the nip rollers 2OB or 2OA. The distance from the nip rollers 2OA to the gear wheels 24 may be less than 2 m or less than 1.5 m or more than 0.5 m or in the region of 1 m.

When sheet is being withdrawn from the roll this is normally achieved by a fixed rate of feed. Consequently as the roll decreases in diameter the rate of rotation will increase and thus the induced current will increase. When the paper runs off the roll the roll may still undergo at least a partial rotation. However, the rotation rate will be decreasing. Consequently the control may be arranged to detect the decrease in current flow indicating that the roll has run out and thereby stop the machine.

Alternatively or additionally the control may be aware of what the current will be when the roll has run out or is just about to run out and the control may stop the machine for a roll change at or just before the roll has run out.

When a new roll is loaded the control may be reset to operate as previously described.

The present invention has been described in relation to the dunnage making machine shown in Figures 1 to 8. It will be appreciated that the invention is applicable to other machines that require material, which may be paper or of other material, to be withdrawn from a roll. Furthermore, whilst the metal portion is shown as being in a central region in the drawings it could be at any extent along the roll including the end of the roll such as the end face of a roll.

Claims

1. A hollow wound roll including, at an inner region, a metal portion at at least one extent along the axis of rotation of the roll which metal portion only extends part of the way around the axis whereby, in use, rotation of the roll and thereby the metal portion is arranged to induce a signal from an inductive device located in the hollow roll to allow effective operation of a machine unwinding material from the roll to continue.

2. A roll as claimed in claim 1 in which the metal portion is located at a middle region along the axis of rotation of the roll.

3. A roll as claimed in claim 1 or 2 in which the roll includes a core on which the roll is wound.

4. A roll as claimed in claim 3 in which the metal portion is attached to the core.

5. A roll as claimed in claim 4 in which the metal portion is attached to the core by an adhesive member.

6. A roll as claimed in any preceding claim in which the wound roll comprises a wound paper roll.

7. A machine arranged, in use, to process material coming off a hollow wound roll which roll includes a metal portion at at least one extent along the axis of rotation of the roll which metal portion only extends part of the way around the axis, the machine including a stationary conductor arranged, in use, to be located in a hollow wound roll whereby, in use, rotation of a roll and thereby its metal portion is arranged to induce a current in the stationary conductor to allow effective operation of the machine to continue with material being unwound from the roll.

8. A machine as claimed in claim 7 in which the machine includes a control.

9. A machine as claimed in claim 8 in which the control is arranged to monitor whether a signal is received from the inductive device or not.

10. A machine as claimed in claim 9 in which the control is arranged to stop effective operation of the machine if the control does not receive a signal from the inductive device.

11. A machine as claimed in claim 10 in which the control is arranged to stop effective operation of the machine if the control does not receive a signal from the inductive device.

12. A machine as claimed in claim 11 in which the predetermined event is a duration of time.

13. A machine as claimed in claim 12 in which the duration of time is arranged to commence after material has commenced being unwound.

14. A machine as claimed in any of claims 11 to 13 in which the predetermined event is a predetermined length of material having been withdrawn from the roll.

15. A machine as claimed in any of claims 7 to 14 in which the control includes a reset whereby after the control has stopped effective operation of the machine effective operation can recommence upon activation of the reset.

16. A machine as claimed in claim 15 in which activation of the reset is arranged to be able to recommence effective operation of the machine after a predetermined period of time from when effective operation has been stopped.

17. A machine as claimed in any of claims 7 to 16 in which the machine includes at least one driven member arranged, in use, during effective operation to unwind material from a roll.

18. A machine as claimed in any of claims 7 to 17 in which the machine comprises a dunnage and making machine.

19. A machine as claimed in any of claims 7 to 18 including a hollow wound roll as claimed in any of claims 1 to 6.

20. A method of operating a machine to process material coming off a wound roll, the method comprising inducing a signal caused by a metal portion of the roll rotating around an inductive device as the roll rotates during unwinding and monitoring whether or not an induced signal is generated.

21. A method as claimed in claim 20 comprising allowing effective operation to continue when an induced current is generated.

22. A method as claimed in claim 20 or 21 comprising causing effective operating to cease when an induced signal is not generated.

23. A method as claimed in claim 22 comprising preventing effective operation from recommencing until after a predetermined period of time has elapsed since effective operation ceased.

24. A method of operating a machine as claimed in any of claims 20 to 23 when operating a machine as claimed in any of claims 7 to 19.