NZ607809B2 - Improvements in and Rrelating to Paperboard Manufacture - Google Patents

Abstract

607809 A machine for producing corrugated paperboard which includes: an endless fluted conveyor belt assembly having an endless fluted conveyor belt including a plurality of adjacent flutes thereon wherein the flutes are configured to correspond to the teeth on a corrugating roller which is located at the upstream end of the endless fluted conveyor assembly; at least one source of electromagnetic radiation and associated support surface located downstream of a glue applicator, the associated support surface also positioned substantially parallel to, the plane of the endless fluted conveyor belt said associated support surface also being sufficiently proximate to the flutes on the endless fluted conveyor belt, so as in use?to be capable of at least partially holding newly glued planar sheet and corrugated sheet material together. at the upstream end of the endless fluted conveyor assembly; at least one source of electromagnetic radiation and associated support surface located downstream of a glue applicator, the associated support surface also positioned substantially parallel to, the plane of the endless fluted conveyor belt said associated support surface also being sufficiently proximate to the flutes on the endless fluted conveyor belt, so as in use?to be capable of at least partially holding newly glued planar sheet and corrugated sheet material together.

Description

JAWS Ref: 237594/14 JV PATENTS FORM NO. 5 Fee No. 4: $250.00 I l PATENTS ACT 1953 COMPLETE SPECIFICATION IMPROVEMENTS IN AND RELATING TO PAPERBOARD MANUFACTURE We, Corcel IP Limited, a New Zealand company of c/- Level 12, KPMG Centre, 85 Alexandra Street, Hamilton, New d; hereby e the invention for which we pray that a patent may be granted to us, and the method by which it is to be performed to be particularly described in and by the following statement: JAWS Ref: 23759414 JV IMPROVEMENTS IN AND RELATING TO PAPERBOARD MANUFACTURE TECHNICAL FIELD The present invention relates to improvements in and relating to paperboard manufacture.

BACKGROUND ART In the manufacture of conventional corrugated paperboard the corrugated sheet al is formed by running the paper to be corrugated in between two corrugating rollers.

This is illustrated in the exemplary example depicted in Figure 1 which is taken from US 4,447,285. In Figure 1 it can be seen the paper after being meshed between the two intermeshing rollers travels at least partially around one of the rollers to enable the newly formed paper flutes to remain in contact with the corrugations of the roller following formation.

This retention of the newly fluted paper t the corrugations of the ating roller - post intermeshing: of the paper between the opposed corrugating rollers - helps to reduce degradation cf the newly imparted flute profile to the paper: prior to lamination to a planar liner sheet. In addition, this ion enables a glue roller to t the flute tips t deforming the flutes as they are resting on the ated teeth of the ating roller; and this also enables a pressure roller to contact and apply pressure to the flute tips, as the liner sheet is brought into {contact to form single face corrugated paperboard.

However, a drawback of conventional corrugators as shown in Figure 1 is that they turn the freshly corrugated medium through at least 90% or more, as it travels around one of the corrugator rollers. The reason why this turning is a drawback, is that it places the paper under undue tension which in turn causes some flattening of the corrugations.

It is an object of the present invention to address the foregoing problems or at least to provide the public with a useful choice.

All references, ing any patents or patent applications cited in this specification are hereby incorporated by reference. No admission is made that any reference constitutes prior art. The discussion of the references states what their authors assert, and the applicants reserve the right to challenge the accuracy and pertinency of the cited documents. It will be clearly understood that, although a number of prior art publications are referred to herein, this reference does not constitute an admission that any of these documents form part of the JAWS Ref: 237594/14 JV common general knowledge in the art, in New Zealand or in any other country. hout this specification, the word "comprise", or variations thereof such as "comprises" or "comprising", will be understood to imply the inclusion of a stated element, integer or step, or group of elements integers or steps, but not the exclusion of any other element, integer or step, or group of elements, integers or steps.

Further aspects and advantages of the present invention will become apparent from the ensuing description which is given by way of example only.

DEFINITIONS The term ‘associated support surface’ as used herein refers to a substantially planar surface from or through which omagnetic magnetic radiation is, or can be, emitted, whether directly or indirectly.

The term ‘industrial inkjet r’ as used herein refers to a single pass high speed inkjet printer which has a printer head which has an array of nozzles which span the width of the material to be printed and preferably includes a heat .

Y OF INVENTION According to a first aspect there is provided a machine for producing corrugated paperboard which includes: - an endless fluted conveyor belt assembly having an endless fluted conveyor belt including a plurality of adjacent flutes thereon wherein the flutes are configured to correspond to the teeth on a corrugating roller which is located at the upstream end of the s fluted conveyor assembly; — at least one source of electromagnetic radiation and associated support surface located downstream of a glue applicator, the associated t e also positioned substantially parallel to, the plane of the s fluted conveyor belt said ated support surface also being sufficiently proximate to the flutes on the endless fluted conveyor belt, so as in use, to be e of at least partially holding newly glued planar sheet and corrugated sheet material together.

JAWS Ref: 237594/14 JV According to a second aspect of the present ion there is provided a machine for producing corrugated paperboard substantially as described above wherein the associated support surface covers a source of omagnetic radiation.

According to a third aspect of the present invention there is provided a machine for producing corrugated paperboard substantially as described above wherein the associated support surface is also the source of electromagnetic radiation itself.

According to ‘a fourth aspect of the present invention there is provided a machine for producing corrugated paperboard substantially as described above wherein the source of electromagnetic radiation and associated support surface are located adjacently downstream of a redirect bar which brings the planar sheet into contact with droplets of glue on the crests of the corrugated sheet material.

According to fa fifth aspect of the present invention there is provided a machine for producing corrugated paperboard substantially as described above wherein the associated t e is located adjacently downstream of a redirect bar which brings the planar sheet into contact with ts of glue on the crests of the ated sheet material.

According to a sixth aspect of the t invention there is provided a machine for producing ated paperboard substantially as described above n the machine includes an endless ned belt assembly which holds planar sheet material and the corrugated sheet material together so a bond is formed there n which is located adjacently downstream of the source of electromagnetic radiation and associated support surface.

According to a seventh aspect of the present invention there is provided a e for producing corrugated paperboard substantially as described above wherein the machine includes a laminator module comprising: - upper and lower opposed contact es at least one being in the form of a tensioned conveyor belt, the upper and lower opposed contact surfaces, in use, being configured to receive and press there between: a) planar sheet material; and b) single face corrugated sheet material from the corrugator module; and JAWS Ref: 237594/14 JV — a glue applicator for applying adhesive to the single face corrugated board and/or planar sheet material prior to travelling between the upper and lower contact surfaces which hold the planar sheet material and single face corrugated board together so a bond is formed there n; and - wherein either the upper or the lower opposed contact surface includes as part thereof, or is formed from, at least one source of electromagnetic ion and associated support said associated support surface being oned so as to at least partially hold newly glued double face sheet material together.

According to the eighth aspect there is provided a corrugated sheet material substantially as described above. According to a ninth aspect there is provided a e for producing corrugated paperboard substantially as described above wherein the machine includes an inkjet printer which is oned to print a planar liner sheet prior to the liner sheet being bonded to a corrugated sheet material. ing to a tenth aspect there is provided a machine for producing ated paperboard substantially as described above wherein the machine includes a galvo-head laser unit positioned to cut paperboard exiting the machine.

According to a th aspect there is provided a machine for producing corrugated paperboard via a process not requiring steam which includes an industrial inkjet printer which is positioned to print a liner sheet prior to the liner sheet being bonded to a corrugated medium.

According to a twelfth aspect there is provided a machine for producing corrugated paperboard via a process not requiring steam which includes a galvo-head laser unit positioned to cut paperboard exiting the machine.

According to a thirteenth aspect there is provided a method of increasing the speed of a machine for producing corrugated paperboard via a process not ing steam via use: - an upstream industrial inkjet r; to warm the liner sheet prior to bonding to a corrugated medium.

JAWS Ref: 237594/14 JV BRIEF DESCRIPTION OF THE DRAWINGS Further aspects of the present invention will become apparent from the ensuing description which is given by way of example only and with reference to the anying drawings in which: Figure 1 shows exemplary prior art corrugator taken from Figure 2 of US4,447,285.

Figure 2 shows a schematic perspective view of a single face linear corrugator in accordance with one aspect of the present invention; Figure 3 shows a side view of a double face linear corrugator in accordance with another aspect of the present invention; Figure 4 shows a schematic side view of a double face linear corrugators in accordance with r aspect of the present invention.

BEST MODES AND ILLUSTRATIVE EXAMPLES Figure 2 shows an apparatus for manufacturing single face corrugated sheet material in the form of a single face linear corrugator generally indicated by arrow (100). Figure 3 shows the single face corrugator (100) of Figure 2 fitted with a double facer laminating station. For ease of reference the paper sheets used in the corrugator (100) are shown in Figure 3 and not Figure 1.

In Figure 2 the single face linear ator (100) has an endless slatted or belt assembly (101) having an endless fluted conveyor belt (102) — (formed from a plurality of nt fluted slats (not shown)) - which is driven by a drive mechanism having a motor (not shown) and drive sprockets (103). The endless or belt assembly (101) has a number of dummy rollens (104) which keep the conveyor belt (102) pressed onto: - an associated support surface in the form of a sheet quartz glass (111) which covers a source of electromagnetic radiation in the form of a bank of medium wave infrared heaters (112) which span: across the width of the corrugator, and along the length of the glass 111 in the direction in which the newly glued single face oard travels; and - an endless tensioned belt ly (150).

The drive mechanism and rollers of the endless tensioned belt assembly (150) are not shown given such arrangements are well known in the art.

JAWS Ref: 4/14 JV The linear single face corrugator (100) has a corrugating roller (106) which is formed by a number of spaced apart adjacent corrugating discs which are located a spindle (198). In between each of the corrugating discs are support fingers (199) which hold the Kraft paper to be corrugated (180) against the fluted slats on the endless fluted conveyor belt (102) as the paper (180) enters the corrugator (100).

The endless slatted conveyor belt assembly (101) has a vacuum pump (105) which can apply a vacuum to freshly corrugated sheet material in the form of Kraft paper (not shown) which has just passed in between ating roller (106) and s slatted conveyor belt (102). Gaps between the adjacent slats allow the vacuum to be imparted onto the ated Kraft paper — this feature is known in the art and is shown in Figure 11 of the applicant’s earlier patent application .

After g the corrugating roller (106) the corrugated Kraft paper has a controlled amount of adhesive (not shown) applied to the apex contact portions (not shown) of the crests (not shown) via a glue roller (108) which has a helically grooved surface (not depicted). In use, ve is taken from a glue tray (not shown) and transferred to the glue roller (108) via a glue p roller (109).

A planar sheet of material in the form of Kraft paper (herein the “first liner sheet") (181) passes around a redirect bar (110) and is feed between the endless fluted conveyor surface (102) and the associated t surface (111). The redirect bar (110) as well as a set of dummy rollers (104) in conjunctidn with surface (102) apply pressure to the corrugated paper and liner sheet to hold them togethelr until the bond is at least partially formed.

Additionally, the heat from the medium wave IR heater (112) helps set the glue which will hold the corrugated paper to the liner sheet to form single face paperboard (182). To further ensure a bond has formed between the corrugated paper and the liner sheet the newly formed single face paperboard (182) then travels along endless tensioned belt assembly (150). The length of the source of electromagnetic radiation and associated support surface (111) relative to the direction in which the newly formed corrugated paperboard travels, depends on the speed at which the newly formed corrugated oard is travelling, and bond time of the adhesive used.

JAWS Ref: 237594/14 JV Figure 3 shows a double facer apparatus as indicated by arrow (200). The apparatus (200) situated below a single face corrugating module in the form of a linear corrugator (100) substantially as described above in on to Figure 2.

As can be seen Kraft paper (180) to be corrugated enters the linear corrugator (100) upstream of ating roller(106) and Kraft paper (181) which will form the first liner sheet enters the linear corrugator (100) after the glue rollers (108,109) as shown.

The double facer (200) has opposed upper and lower contact surfaces which are in the form of endless opposed tensioned belt assemblies (201,202) and a glue applicator and nip roller assembly (203) through which the single face corrugated board (182) passes before entering the double facer (200). The glue roller assembly (203) is substantially the same as that described in relation to Figure 2. The Kraft paper (183) which forms the double face liner sheet enters the apparatus (200) and travels above the top of the endless slatted conveyor (101) of the linear corrugator (100) on support bars (204) before it enters the double facer (200) together with the single face corrugated board at the point indicated by arrow (205).

The double facer (200) also has as part of the lower contact surface an associated t surface (206) positioned above an source of electromagnetic radiation in the form of a bank of medium wave infrared heaters (207) positioned adjacent and downstream of the redirect bar (208) which directs the liner sheet (183) into the double facer (200).

It will be apprbciated by those skilled in the art that the planar sheet al used in the embodiments shown in Figures 2 and 3 can in some embodiments be pre-printed with high quality graphic images and/or text . For example, in Figure 3 the planar sheet material (183) can be pre-printed.

In Figure 4 there is an apparatus (1000) for ing double face ated paperboard. The apparatus is similar to that shown in Figure 3 but includes a number of further features: First, the tus (1000) includes an industrial UV inkjet printer (1001) manufactured by XAAR aar.com) through which first liner sheet (1002) passes before going around redirect bar (110) and being fed between the endless fluted conveyor e (102) and associated support e (111).

Second, the apparatus (1000) includes a galvo—head CNC laser station (1003) which receives double face board (1004) exiting the double facer (200). The galvo-head CNC laser station JAWS Ref: 237594/14 JV (1003) cuts, scores or marks the double face board ing to the product that is sought to be produced as pre—programmed. For example, the galvo-head CNC laser station can produce box blanks (1005) or other corrugated product blanks (not shown). The head CNC laser station includes an optical scanner which enables the laser to track the varying speed of the paperboard.

This embodiment has a number of features which provides additional advantages which can include: - the y to print high quality graphic images as part of a continuous or line process for the manufacture of paperboard; — the y to increase the speed at which d paperboard is produced; - the ability to increase the speed of the paperboard manufacturing process when the industrial inkjet printer has a heat source which pre-heats the liner sheet which reduces the cure time for the adhesive; and — the y to produce boxes which are pre-printed as part of a continuous process for the manufacture of paperboard.

DETAILED DISCUSSION OF ALTERNATE WAYS TO IMPLEMENT THE INVENTION The electromagnetic radiation source may e any source electromagnetic radiation e of directly or indirectly heating paper and/or heating or curing adhesive suitable for bonding sheets of paper to one another.

In some embodiments there may be two or more different types of electromagnetic radiation.

For example, there may be infrared radiation and UV ion sources.

In some embodiments the additional types of radiation source may be utilised for purposes other than curing the adhesive.

In one embodiment the electromagnetic radiation source may be a medium wave IR heater.

In another embodiment the electromagnetic radiation source may be a medium wave carbon infrared heater.

JAWS Ref: 237594/14 JV In a further embodiment the electromagnetic radiation source may be a medium wave quartz infrared heater.

In a further embodiment the electromagnetic ion source may be medium wave IR LEDs.

In another embodiment the electromagnetic radiation source may be a medium wave ceramic IR heater.

In still a r embodiment the electromagnetic ion source may be a UV lamp.

The associated support surface may come in a variety of different forms without departing from the scope of the present invention.

In one embodiment the associated t surface may have a continuous uninterrupted support surface provided said surface emits electromagnetic radiation, or allows electromagnetic radiation, to pass therethrough.

In another embodiment the associated support surface may have a number of holes or slots therein which allow electromagnetic radiation to pass hrough. The holes and slots being arranged so the associated support surface is still capable of supporting the newly formed corrugated single face or double face paperboard.

In one embodiment the associated support surface may be CLEARCERAMTM glass-ceramic.

In another embodiment the associated support may be a quartz glass.

In some ments the glass may be a low thermal expansion glass.

The associated support surface may preferably be arranged to be capable of being raised or lowered with t to the endless fluted conveyor. This ability to move the associated support surface s and away from the endless fluted conveyor provides a number of advantages, two non-limiting examples are: - adjusting the degree of pressure placed on the planar and corrugated sheet als during the lamination process; and — allowing the EMR e to be automatically moved away from t with the planar and corrugated sheet materials if the machine is stopped so as to lessen any risk of fire.

JAWS Ref: 237594/14 JV Aspects of the present invention have been described by way of e only and it should be appreciated that modifications and additions may be made thereto without departing from the scope thereof as defined in the appended claims.

JAWS Ref: 237594/14 JV

Claims (1)

WHAT WE CLAIM IS:

1. A machine for producing corrugated paperboard which includes: —— an endless fluted conveyor belt assembly having an endless fluted conveyor belt including a ity of adjacent flutes thereon n the flutes are configured to correspond to the teeth on a ating roller which is located at the upstream end of the endless fluted conveyor assembly; — at least one source of electromagnetic radiation and associated support surface located downstream of a glue applicator, the associated support surface also positioned substantially parallel to, the plane of the endless fluted conveyor belt said associated support surface also being sufficiently proximate to the flutes on the endless fluted conveyor belt, so as in use, to be capable of at least partially holding newly glued planar sheet and corrugated sheet material together. A machine for producing corrugated paperboard as claimed in claim 1 wherein the associated support e covers a source of electromagnetic radiation. A machine for producing corrugated paperboard as claimed in claim 1 wherein the associated support e is also the source of electromagnetic radiation itself. A machine for producing corrugated paperboard as claimed in any one of the preceding claims wherein the source of electromagnetic ion and associated support surface are located adjacently downstream of a redirect bar which brings the planar sheet into contact with droplets of glue on the crests of the corrugated sheet al. A machine for ing ated paperboard as claimed in any one of the preceding claims n the machine includes an endless tensioned belt assembly which holds planar sheet material and the corrugated sheet material together so a bond is formed there between which is located adjacently downstream of the source of electromagnetic ion and ated support surface. A machine for producing corrugated paperboard as claimed in claim 1 wherein the e includes a laminator module comprising: JAWS Ref: