GB2462877A

GB2462877A - Board connection apparatus

Info

Publication number: GB2462877A
Application number: GB0815456A
Authority: GB
Inventors: Alan Mayo
Original assignee: SUBITO TECHNOLOGY SYSTEMS Ltd
Current assignee: SUBITO TECHNOLOGY SYSTEMS Ltd
Priority date: 2008-08-26
Filing date: 2008-08-26
Publication date: 2010-03-03
Anticipated expiration: 2028-08-26
Also published as: GB0815456D0; GB2462877B

Abstract

An apparatus and method feature a board connection station with a heat source 4 and pressure source 5 on opposite sides of the board A,B. Apertures (6,fig.3) are provided in, or in the region of, the pressure source, which may be a plate (12,fig.3). The aperture or apertures may allow the release of steam as the faces A, B of the board are heated, pressured, and glued together. The apparatus may be used to create double faced corrugated card. Also disclosed is a related kit of parts of the plate assembly. Also disclosed is an apparatus and method using of parallel pivots on pressure plates.

Description

BOARD CONNECTION

The present invention relates to board connecting apparatus, a method of connecting board and a kit of parts for use in board connection. The present invention is particularly, but not exclusively related to bonding of single or multiple layers of corrugated papers by double facer machines.

Double facers are machines in which board comprising a lining material and a single/multiple corrugated cardboard membrane, a single faced board, is bonded to a liner to form double faced board. To achieve the bonding, an adhesive is applied to the tips of the corrugated membrane, which is conveyed along with the liner into an upstream end through to a downstream end of the double facer by a belt. In the double facer the single faced board and liner are pressed down onto a series of hot plates to form the double faced board.

The prior art discloses a number of ways in which the single faced board and liner can be pressed together to form double faced board. One such way is disclosed in GB2233935.

The pressing is achieved by inflating an air bag over each of a series of hot plates to provide the pressure needed to press the single faced board and liner together. The airbag is a single chambered vessel and it has been found that the pressure provided is often not evenly distributed across the plates. As a result, the double faced board produced by such a double facer has a tendency to become warped and/or for the liner sheet to become delaminated from the single faced board.

In addition, the airbags tend to be arranged across the entire surface of the plate in a direction transverse to the direction in which the single faced board and liner are conveyed. A large amount of moisture is generated by the double facer as the single faced board and liner are bonded and it is difficult for that moisture to be released. This leads to a large amount of moisture being retained by the double faced board that is conveyed out of the double facer.

As a result, the bond between the single faced board and liner is often weak leading to delamination and the warping is enhanced due to the rapid cooling that occurs as the large amount of moisture is released from the double faced board after being conveyed out of the downstream end of the double facer.

It is an aim of the present invention to address the problems associated with double facers whether identified herein or otherwise.

The present invention is defined in the claims and elsewhere in this specification.

The present invention may be carried out, in practice, in various ways but an exemplary embodiment will now be described, by way of example and with reference to the accompanying drawings in which: Figure 1 is a side view of a double facer of an embodiment of the present invention; Figure 2 is a plan view of a plate of an embodiment of the present invention for use in the double facer of Figure 1; Figure 3 is a plan view of a plate member of the plate shown in Figure 2; Figure 4 is a side view of the plate member shown in Figure 3; Figure 5 is a plan view of a plate member of the plate shown in Figure 2 with a spacer of the present invention connected thereto; Figure 6 is a side view of a pressure providing unit of an embodiment of the present invention for use in the double facer of Figure 1; Figure 7 is a front view of the pressure providing unit of Figure 6; Figure 8 is a plan view of the pressure providing unit of Figure 6, and Figure 9 is a plan view of pressure loading vessels used in one of the pressure providing units ofFigure6.

Figure 1 shows an embodiment of a double facer 1 of the present invention. In operation, a belt 2 conveys into an upstream end 3 of the double facer 1 a board A comprising a connected liner and a corrugated board and a liner B. Bonding glue has been applied to the exposed tips of the corrugated board. In the double facer 1, the single faced board A and liner B are pressed together by succession of connection stations. Each station comprises a series of hot plates 4 against which the board is pressed by a plurality of plates 5 arranged transverse to the direction the single faced board A and liner B are conveyed, the hot plates 4 being cast iron, steel or other form of hotplate/heating system. The heat bonds the corrugated board to the liner. Each plate 5 comprises an aperture 6 to allow moisture to be released from the board in the direction of arrows, as shown in Figure 6. Allowing moisture to be released from the board from within the double facer 1 reduces the level of residual moisture present in the double faced board exiting the double facer 1 thereby reducing the likelihood of the board warping and or delaminating as it cools.

Figure 2 shows an example of the plate, in the region of 3 mm thick, used to press the single faced board against the liner in the double facer 1. Each plate 5 is an elongate sheet material having a top surface 7 and a bottom surface 8. In use, the top surface 7 receives pressure from a pressure source and the bottom surface 8 is adjacent to the hot plate 4 to press the single faced board A against the liner B being conveyed relative to the plate in the direction of the arrow shown in Figure 2.

The plates 5 have a plurality of apertures 6 extending across a central region 9. Either side of the central region 9 are first and second edge regions 10,11. The edge regions 10,11 are the areas to which pressure is applied to the plates 5 to, in use, leave the central region 9 uncovered to enable moisture to escape from the board through the apertures 6. The length to width direction of the apertures may be less than 12:1 or 8:1 or more than 2:1 or 4:1 or in the region of 6:1.

The plates 5 each comprise a plurality of plate members 12. The plate members 12 are connected so that they are spaced apart from each other to leave a small gap therebetween.

The small gap provides a tolerance to the plates 5 that allows the plate members 12 to expand, in use, as a result of the heat given off by the hot plates 4. The small gap also adds to the ability of the plates 5 to allow moisture to be released from the material running between the plates 5 and the hot plates 4. The small gap is between 1mm to 2.2mm in width, for example, 1.6mm in width. The plate S also comprises two end plate members 13,14 having a smaller width than the other members 12.

To provide the small gap between the plate members 12 spacers 15 are used as shown in Figure 5. The spacers 15 have extensions which are inserted either side and between end connection 16,17 of the plate member 12. The spacers are wider that the plate members 12 so that when they are connected together the spacers abut each other to maintain the small gap between the plate members 12.

In an embodiment (not shown), adjacent edges of the plate members 12 comprise a recess in the central region 9. When the plate members 12 are connected to form the plate, the recesses are aligned to define a large gap or an opening through which moisture can pass, in use. In this embodiment, the opening may be provided instead of or in addition to the aperture 6.

To accommodate for varying sized double facers a varying number of plate members are connected together. In this way, the plates 5 can be adapted to suit any size of double facer 1 by simply connecting together more or less plate members 12 between the end members 13,14. The inner plate members 12 are between 130mm and 170mm in width, for example 152mm in width. The plates are between 100mm to 120mm in width, for example 110mm in width.

Figures 3 and 4 show one of the plate members 12 in more detail. In addition to an aperture 6 and the first and second end connections 16,17, the plate member 12 also comprises a first and a second strengthener 18,19. The strengtheners 18,19 are upturned side portions of the plate members 12 that add strength to the plate members 12 and the plate assembly 5.

The connections 16,17 comprise a channel through which a rod is passed to connect the plate members 12 and the spacers 15 together.

As can be seen from Figures 6 and 7, the spacers 15 also serve to connect the plate 5 to a pressure providing unit 20 about a hinge. The pressure providing unit 20 applies pressure to the plate 5 to pinch the single faced board and liner together on the hot plate 4, in use.

The plate 5 and pressure providing unit 20 are connected about a hinge so that ends of the plate 5 that comprise the connections 16,17 are transverse to the direction in which the material passes between the plate 5 and hot plate 4. The hinged connection introduces some give that minimises the likelihood that the plate 5 will jar about its connection to the pressure providing unit 20 when the material is initially conveyed into the double facer 1.

Both connections 16,17 are linked about their hinges to the pressure providing unit 20 via the spacers 15 and a further hinge 26 at the spacer unit so that the bottom surface 8 is in a plane parallel to the material being conveyed through the double facer 1. In this way, the plate 5 moves about the hinge relative to the pressure providing unit 20 in a trapezoidal manner thereby ensuring that the pressure applied from the bottom surface 8 is evenly distributed across the material with the gap between the plates and the opposed hot plates 4 being constant across the plate regardless of the depth of that gap.

The pressure providing unit 20 can use pressure loading vessels, springs or other loading devices to apply pressure to the edge regions 10,11.

In the exemplary embodiment shown in Figures 6, 7 and 8, the pressure providing unit 20 uses pressure loading vessels 21,22 to apply pressure to the edge regions 10,11. The vessels 21,22 can be fluid receiving bags, for example air bags, that each have a cavity which is segmented into chambers 23, 24, 25 shown in Figure 9. Each chamber can receive fluid, for example air, and retain that fluid at pressure independently of the pressure in the other chambers. In one example embodiment, the each cavity can be divided into five chambers, such as one main chamber 23 with two side chambers 24,25 at the opposed ends of the double facer. The air bag is segmented so that the chamber can be selectively inflated to thereby ensure that pressure is only provided to the plates requiring pressure to be supplied.

When narrow board is being processed only the main chamber 23 is inflated thus keeping pressure off the belt at the end regions. When medium width board is being run the chambers 24 are inflated and for full width boards all chambers are inflated.

The pressure providing unit 20 also has a fluid supply system 27. The fluid supply system 27 supplies air to the pressure loading vessels 21,22.

Figure 8 shows the fluid supply system 27 having first, second and third fluid suppliers 28,29, to supply air to the chambers 23, 24, 25. Different pressures can be set for different chambers. Alternatively or additionally the pressure can be at a set level regardless of the speed that the machine is running. Alternatively or additionally in an automatic mode the pressure can follow a curve from a minimum preset pressure up to a requested pressure. The curve may be adjustable. There may also be a memory function which may operate with a memory function so that the unit sets up automatically. Any of the hot plate temperatures or the pressures may be controlled. Diagnostics, run information and on line test/upgrade download capability may also be provided.

The pressure providing unit 20 and plates 5 can be raised away from production and lowered relative to the hot plates 4. They can also be lowered to a predetermined height from the hot plates 4 to accommodate differing depths of board.

Although a few preferred embodiments have been shown and described, it will be appreciated by those skilled in the art that various changes and modifications might be made without departing from the scope of the invention, as defined in the appended claims.

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. Board connection apparatus including driving means arranged, in use, to cause separate webs to be conveyed in a first direction towards and through at least one connection station, the connection station including a heat source arranged on a first side of the webs and a pressure source arranged on a second opposed side of the webs, the pressure source, in use, biasing the webs against each other and biasing the webs against the heat source whereby the webs are connected as they pass through the connection station characterised in that, on the second side, there is at least one opening that is directly opposed to the heat source.
2. Apparatus as claimed in Claim 1 in which the opening is spaced from the ends of the pressure source in the first direction of the connection station.
3. Apparatus as claimed in Claim 1 in which the opening is located centrally from the ends of the pressure source in the first direction.
4. Apparatus as claimed in any preceding claim in which the opening is elongate in the first direction.
5. Apparatus as claimed in any preceding claim in which the opening is arranged to extend across the station in the first direction by more than 20% of the extent of the heat source in the first direction.
6. Apparatus as claimed in any preceding claim in which the opening is arranged to extend across the station along a direction that the webs are intended to travel by more than 30% of the extent of the heat source in the first direction.
7. Apparatus as claimed in any preceding claim including a plurality of openings spaced from each other transverse to the first direction.
8. Apparatus as claimed in any preceding claim in which the pressure source is arranged to act on at least one plate whereby, in use, the plate biases the webs against each other and against the heat source.
9. Apparatus as claimed in Claim 8 in which the plate defines at least part of the opening.
10. Apparatus as claimed in Claim 9 in which, when the plate is viewed in a direction extending through the plane that the webs are arranged to occupy, the pressure source does not extend over the opening.
11. Apparatus as claimed in Claim 10 in which the pressure source is spaced from the opening.
12. Apparatus as claimed in any preceding claim in which at least one opening has a length in the first direction relative to the width perpendicular to that direction ratio of the order of 6:1.
13. Apparatus as claimed in any of Claims 8 to 12 in which the pressure source includes two pressure regions spaced from each other.
14. Apparatus as claimed in Claim 13 in which the two pressure regions extend along each side region of the plate.
15. Apparatus as claimed in any preceding claim in which the pressure source includes at least two pressure locations arranged to act at different extents transverse to the first direction, each location being arranged, in use, to apply different pressure to the second side.
16. Apparatus as claimed in Claim 15 including at least three pressure locations arranged to act at different extents transverse to the first direction.
17. Apparatus as claimed in Claim 15 or 16 in which the pressure of two pressure locations to either side end of an intermediate location are arranged to be the same as each other but different from the intermediate location.
18. Apparatus as claimed in Claim 14, 15 or 17 in which the pressure exerted at a first pressure location is arranged to be less than the pressure of at least one second location.
19. Apparatus as claimed in any of Claims 14 to 18 in which a pressure location extending along the middle of the station is arranged to be of greater length than a pressure location to at least one side of the station.
20. Apparatus as claimed in any of Claims 14 to 19 in which there are a succession of at least five pressure locations along the station each at a different longitudinal extent.
21. Apparatus as claimed in any of Claims 14 to 20 including pressure varying means arranged to vary the pressure applied to at least one location.
22. Apparatus as claimed in any of Claims 8 to 21 in which the pressure source includes at least one loading device arranged to act between a plate and a reactive member, the plate being movable relative to the reactive member towards or away from the heat source.
23. Apparatus as claimed in claim 22 in which the loading device is an inflatable air bag.
24. Apparatus as claimed in any of Claims 8 to 23 in which the plate is connected at each side region to a reactive member by parallel links that are both pivotally connected at one end to the plate and at the other end to the reactive member.
25. Apparatus as claimed in any of Claims 8 to 24 in which the plate comprises a plurality of plate members extending transversely to the first direction of travel of the webs.
26. Apparatus as claimed in Claim 25 in which each plate member is connected to an adjacent plate.
27. Apparatus as claimed in Claim 25 or 26 in which each plate member is constrained to move with an adjacent plate member.
28. Apparatus as claimed in any of claims 25 to 27 wherein at least one plate member comprises the opening.
29. Apparatus as claimed in any of Claims 25 to 28 in which the opening is defined by adjacent plate members that are spaced from each other.
30. Apparatus as claimed in any of Claims 25 to 29 in which the opening is defined by adjacent edges of plate members, at least one of which is recessed.
31. Apparatus as claimed in any preceding claim in which the apparatus comprises a double facer apparatus arranged, in use, to connect a lining bonded on one side to a corrugated cardboard member to a liner on the other side.
32. A method of connecting two or more webs together comprising conveying the webs to and through a connection station, applying heat to a first side of the webs and applying pressure to the second opposed side of the webs thereby biasing the webs against each other and biasing the webs towards the heat on the first side and thereby connecting the webs and allowing steam to escape from at least one opening in the second side which opening is directly opposed to where heat is applied to the web from the first side.
33. A method as claimed in Claim 32 comprising allowing the steam to escape from an opening in the second side inwards from the side regions of the web.
34. A method as claimed in Claim 32 or 33 comprising applying pressure to at least one plate that extends across the webs.
35. A method as claimed in any of Claims 32 to 34 comprising applying different pressure to the second side of the web at different extents across the web.
36. A method as claimed in any of Claims 32 to 35 comprising varying the pressure at different extents across the web.
37. A method as claimed in any of Claims 32 to 36 comprising applying pressure to a plate comprising a plurality of plate members extending adjacent to each other across the length of where the webs are connected with each plate being constrained to move together.
38. A method as claimed in Claim 37 comprising causing the plates to move about a parallelogram linkage when moving towards or away from the heat source.
39. A method as claimed in any of Claims 32 to 38 comprising biasing the webs towards each other and towards the heat source by inflatable means.
40. A kit of parts for use in board connection apparatus, the kit of parts comprising a plurality of plate members arranged, in use, to be connected together to form a plate assembly, the kit further including connecting means arranged, in use to connect the plate members together to define a surface arranged, in use, to be urged to bias webs to be connected together towards each other and towards a heat source, the connected plate members defining a plurality of openings arranged, in use, to be directly opposed to a heat source.
41. Board connection apparatus including driving means arranged, in use, to cause separate webs to be conveyed in a first direction through at least one connection station, the connection station including a heat source arranged, in use, to be on a first side of the webs and a pressure source arranged, in use, to be on a second side of the webs, the pressure source including a plate arranged to urge the webs towards the heat source, characterised in that the plate has a first and second pivot at a forwards and rearwards extent respectively with respect to the first direction and in that first and second spacers extend respectively from the first and second pivots, each spacer also being mounted about third and fourth pivots respectively, the third and fourth pivots being spaced from each other and spaced from the first and second pivots, the pivots all being parallel to each other and the angle with respect to the first and third pivots with respect to the first direction being the same as the angle between the second and fourth pivots with respect to the first direction at any one extent of pivotal movement of the plate.
42. Apparatus as claimed in Claim 41 in which the axes of the pivots are perpendicular to the first direction.
43. Apparatus as claimed in Claim 41 or 42 in which the plate comprises a plurality of plate members.
44. Apparatus as claimed in any of Claims 41 to 43 in which the plate includes an opening directly opposed to the heat source.
45. Apparatus as claimed in any of Claims 41 to 44 when the apparatus is as claimed in any of Claims 1 to 40.
46. A method of connecting two webs together comprising conveying the webs to and through a connecting station in a first direction and applying heat to a first side of the webs and pressure to a second, opposed side of the web with a plate, the plate moving about parallel pivots whereby a planar surface of the plate that faces the heat source moves in the first direction towards and away from the heat source such that, in different position of the plate, the planar surface occupies parallel planes.
47. A method as claimed in Claim 46 when using apparatus as claimed in any of Claims 1 to 40.