GB2467399A

GB2467399A - Metal roll stopper.

Info

Publication number: GB2467399A
Application number: GB0918133A
Authority: GB
Inventors: Trevor Davey; John Townsend
Original assignee: Easypack Ltd
Current assignee: Easypack Ltd
Priority date: 2009-02-03
Filing date: 2009-10-16
Publication date: 2010-08-04
Also published as: GB201111064D0; WO2010089584A1; GB0918133D0

Abstract

A feed roll 12, such as for a bag or dunnage making machine, has a metal portion 42 carried on the roll, such as internal to the roll support tube 8. When the roll is placed on a machine mounted roll support 50, an inductive sensor 52 is induced by the metal portion 42 as the roll rotates. In this manner the machine electronics may be able to identify whether the correct feed roll 12, has been attached to the machine. Monitoring means 48 stop a machine to which the roll 12 is attached, on receipt of a particular signal from the sensor 52 such as when the speed of the roll reduces, or the roll stops, because it has become empty of material. This may protect working parts of a dunnage making machine to which the roll 12 of material is attached. Also disclosed is a corresponding method of usage.

Description

MACHINE CONTROL

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.

W095/3 1296 discloses a packaging making machine, in which: Figure 1 is a plan view of a dunnage forming machine; Figure 2 isa 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 waIl 18 that extends through approximately 1800.

The paper is pulled off the rofl 12 by two pairs of spaced rear rubber nip rollers 20A and a forward pair of rubber nip rollers 20B. 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 20A to allow the free end of paper, on start up, to be fed directly into the rollers 20A. If desired, the rollers 20B 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 20B 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 1800 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.

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.

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 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 roIl 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 W095/31296. It will be appreciated that the roll 12 may be arranged to supply any other machine including other dunnage making machines.

The core 8 which is fitted with 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 20A or 20B 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.

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 20B or 20A. The distance from the nip rollers 20A 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.

Attention is directed to all papers and documents which are filed concurrently with or previous to this specification in connection with this application and which are open to public inspection with this specification, and the contents of all such papers and documents are incorporated herein by reference.

All of the features disclosed in this specification (including any accompanying claims, abstract and drawings), and/or all of the steps of any method or process so disclosed, may be combined in any combination, except combinations where at least some of such features and/or steps are mutually exclusive.

Each feature disclosed in this specification (including any accompanying claims, abstract and drawings) may be replaced by alternative features serving the same, equivalent or similar purpose, unless expressly stated otherwise. Thus, unless expressly stated otherwise, each feature disclosed is one example only of a generic series of equivalent or similar features.

The invention is not restricted to the details of the foregoing embodiment(s). The invention extends to any novel one, or any novel combination, of the features disclosed in this specification (including any accompanying claims, abstract and drawings), or to any novel one, or any novel combination, of the steps of any method or process so disclosed.

Claims

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 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.
2. A roll as claimed in Claim 1 in which the predetermined event is arranged to be cessation of the signal.
3. A roll as claimed in Claim 1 in which the predetermined event is a reduction in the signal.
4. A roll as claimed in Claim 1 in which the predetermined event is a specific value for the signal.
5. A machine 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.
6. A machine as claimed in Claim 1 in which the machine is arranged to be stopped before the trailing edge of the roll leaves an output of the machine.
7. A machine as claimed in Claim 6 in which the machine is arranged to be stopped before the trailing edge of the roll reaches an output of the machine.
8. A machine as claimed in Claim 7 in which the machine is arranged to be stopped before the trailing edge of the roll reaches an input to the machine.
9. A machine as claimed in any of Claims 5 to 8 in which the conductor is coextensive with the conductor along the axis of the roll.
10. A machine as claimed in any of Claims 5 to 9 in which the machine coprises a dunnage making machine.
11. A method of monitoring a machine being fed from a hollow wound roll comprising 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.
12. A method as claimed in Claim 11 in which the predetermined extent comprises stopping the machine when the signal stops being generated.
13. A method as claimed in Claim 11 in which the predetermined extent comprises stopping the machine when there is a reduction in the signal.
14. A method as claimed in Claim 11 in which the predetermined extent comprises stopping the machine when the signal reaches a specific value.