WO1999037871A1 - Method for the production of a sandwich panel and core material therefor - Google Patents

Method for the production of a sandwich panel and core material therefor Download PDF

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Publication number
WO1999037871A1
WO1999037871A1 PCT/NL1999/000040 NL9900040W WO9937871A1 WO 1999037871 A1 WO1999037871 A1 WO 1999037871A1 NL 9900040 W NL9900040 W NL 9900040W WO 9937871 A1 WO9937871 A1 WO 9937871A1
Authority
WO
WIPO (PCT)
Prior art keywords
strip
strips
core material
panel
longitudinal edges
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Ceased
Application number
PCT/NL1999/000040
Other languages
French (fr)
Inventor
Dirk Jan Holtslag
Henricus Johannes Maria Krabben
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Honicel Nederland BV
Original Assignee
Honicel Nederland BV
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Honicel Nederland BV filed Critical Honicel Nederland BV
Priority to US09/600,855 priority Critical patent/US6514368B1/en
Priority to EP99900723A priority patent/EP1049838B1/en
Priority to DK99900723T priority patent/DK1049838T3/en
Priority to AT99900723T priority patent/ATE260384T1/en
Priority to DE69915032T priority patent/DE69915032T2/en
Priority to AU19869/99A priority patent/AU1986999A/en
Priority to CA002318873A priority patent/CA2318873C/en
Publication of WO1999037871A1 publication Critical patent/WO1999037871A1/en
Anticipated expiration legal-status Critical
Ceased legal-status Critical Current

Links

Classifications

    • EFIXED CONSTRUCTIONS
    • E04BUILDING
    • E04CSTRUCTURAL ELEMENTS; BUILDING MATERIALS
    • E04C2/00Building elements of relatively thin form for the construction of parts of buildings, e.g. sheet materials, slabs, or panels
    • E04C2/30Building elements of relatively thin form for the construction of parts of buildings, e.g. sheet materials, slabs, or panels characterised by the shape or structure
    • E04C2/34Building elements of relatively thin form for the construction of parts of buildings, e.g. sheet materials, slabs, or panels characterised by the shape or structure composed of two or more spaced sheet-like parts
    • E04C2/36Building elements of relatively thin form for the construction of parts of buildings, e.g. sheet materials, slabs, or panels characterised by the shape or structure composed of two or more spaced sheet-like parts spaced apart by transversely-placed strip material, e.g. honeycomb panels
    • E04C2/365Building elements of relatively thin form for the construction of parts of buildings, e.g. sheet materials, slabs, or panels characterised by the shape or structure composed of two or more spaced sheet-like parts spaced apart by transversely-placed strip material, e.g. honeycomb panels by honeycomb structures
    • YGENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y10TECHNICAL SUBJECTS COVERED BY FORMER USPC
    • Y10TTECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION
    • Y10T156/00Adhesive bonding and miscellaneous chemical manufacture
    • Y10T156/10Methods of surface bonding and/or assembly therefor
    • Y10T156/1002Methods of surface bonding and/or assembly therefor with permanent bending or reshaping or surface deformation of self sustaining lamina
    • Y10T156/1003Methods of surface bonding and/or assembly therefor with permanent bending or reshaping or surface deformation of self sustaining lamina by separating laminae between spaced secured areas [e.g., honeycomb expanding]
    • YGENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y10TECHNICAL SUBJECTS COVERED BY FORMER USPC
    • Y10TTECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION
    • Y10T156/00Adhesive bonding and miscellaneous chemical manufacture
    • Y10T156/10Methods of surface bonding and/or assembly therefor
    • Y10T156/1052Methods of surface bonding and/or assembly therefor with cutting, punching, tearing or severing
    • Y10T156/1062Prior to assembly
    • Y10T156/1066Cutting to shape joining edge surfaces only
    • YGENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y10TECHNICAL SUBJECTS COVERED BY FORMER USPC
    • Y10TTECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION
    • Y10T428/00Stock material or miscellaneous articles
    • Y10T428/24Structurally defined web or sheet [e.g., overall dimension, etc.]
    • Y10T428/24149Honeycomb-like
    • Y10T428/24157Filled honeycomb cells [e.g., solid substance in cavities, etc.]

Definitions

  • the invention relates to the production of a core material for sandwich panels.
  • a core material preferably consists of strips of fibrous material which are joined to one another at their surfaces with the joins offset turn and turn about.
  • a pack of strips joined to one another in this way forms a honeycomb-like structure which combines low weight with high rigidity and strength in the finished panel.
  • the longitudinal edges of the strips are each attached to a cover sheet.
  • the adhesion between the cover sheets and the strips of the core is obtained by means of an adhesive such as, for example, urea formaldehyde adhesive.
  • an adhesive such as, for example, urea formaldehyde adhesive.
  • cover sheets having a closed surface structure such as metal or plastic
  • said adhesive is preferably applied to the longitudinal edges of the strips.
  • cover sheets which consist of an open structure, such as fibrous material the adhesive is applied to said cover sheets themselves.
  • the core material is fed between two rollers, which are optionally provided with a profile. Said rollers roughen the cut surfaces of the strips and as it were make said surfaces open and larger, so that a larger amount of adhesive can be absorbed and the adhesion can be improved.
  • the aim of the invention is to improve the production of such sandwich panels so that, on the one hand, the production process is simplified and, on the other hand, better adhesion between cover sheets and core material is obtained.
  • Said aim is achieved by means of a method for the production of a core material composed of strips of preferably fibrous material for a sandwich panel, in which sandwich panel the width direction of the strips is coincident with the thickness direction of the panel and a cover layer is attached to each of the longitudinal edges of the strips, comprising cutting each strip from a sheet with the formation of, in each case, a longitudinal edge having a cut surface which, viewed in cross-section of the strip, runs at an incline between the two surfaces of the strip.
  • the strips which form the core are cut off from a sheet of starting material in such a way that an oblique cut surface is produced.
  • an oblique cut the surface area of the cut surface is increased and specifically is increased by a factor of 1/cos ⁇ , where ⁇ is the acute angle between the cut surface and the thickness direction of the strip.
  • Said increase in surface area yields a larger surface area of the core available for adhesion to the cover sheets, as a consequence of which the quality of the join is higher.
  • the larger surface area is also able to absorb more adhesive.
  • the better adhesion is obtained on both longitudinal edges of the strips.
  • the strips are cut successively in a continuous process from an even number of sheets of starting material.
  • the angles of the two longitudinal edges of a strip are therefore also complementary.
  • the adhesion of the honeycomb with obliquely cut longitudinal edges can be further improved by a treatment with, for example, rollers, optionally provided with a profile, as a result of which, just as in the case of conventional honeycomb, the cut surfaces are roughened.
  • the angle of the cut surface can be between 20° and 70° with respect to the thickness direction of the strip. Preferably, said angle is approximately 45°.
  • the invention also relates to a method for the production of a panel from a core material and two cover layers, comprising the steps of production of a core material composed of strips of preferably fibrous material, as described above, application of an adhesive to the longitudinal edges of the strips of the core material and/or to the cover layers and pressing the core material and the cover layers onto one another, during which operation the longitudinal edges are deformed as a consequence of their inclined cut surface, which deformed longitudinal edges provide an enlarged area of adhesion 3 between the core material and the cover layers.
  • the oblique shape of the longitudinal edges of the strips in the core leads to an increase in the surface available for adhesion.
  • Said surface available for adhesion is further enlarged as a consequence of the deformation of the longitudinal edges on compressing the pack made up of core and cover sheets. This leads to a further improvement in the adhesion between core and cover sheets.
  • the invention also relates to a panel as produced according to the method described above.
  • Figure 1 shows a section of a core material, made up of strips, in the closed form, each strip consisting of an even number of layers.
  • Figure 2 shows the core material between two cover sheets before fixing to one another.
  • Figure 3 shows a cross-section through a finished panel.
  • the core material 1 shown in Figure 1 is made up of strips 2, consisting of an even number of layers, which are joined to one another, for example by gluing, at their surfaces 3, 4 facing one another with the joins offset turn and turn about.
  • a honeycomb structure is obtained as a consequence of said joins being offset turn and turn about.
  • a honeycomb structure of this type for a core material made up of strips 2 is known and is not further shown.
  • the strips 2 are cut off obliquely at their longitudinal edges 5, 6.
  • the angle ⁇ with respect to their thickness direction 7 can be between 20 and 70°.
  • the angle is preferably 45°.
  • Cover sheets 8, 9 are used to produce a panel from a core material 1.
  • a layer 10 of adhesive is applied to those surfaces of the cover sheets 8, 9 which face one another.
  • the cover sheets 8, 9 can consist of fibrous material, like the strips 2.
  • a bead 14 of adhesive material is formed on both sides of the surface 4

Landscapes

  • Engineering & Computer Science (AREA)
  • Architecture (AREA)
  • Civil Engineering (AREA)
  • Structural Engineering (AREA)
  • Laminated Bodies (AREA)
  • Soft Magnetic Materials (AREA)

Abstract

A method for the production of a core material (1) composed of strips (2) of preferably fibrous material for a sandwich panel, in which sandwich panel the width direction (7) of the strips (2) is coincident with the thickness direction of the panel and a cover layer (8, 9) is attached to each of the longitudinal edges of the strips (5, 6), comprises cutting each strip (2) from an even number of layers with the formation of, in each case, a longitudinal edge (5, 6) having a cut surface (11) which, viewed in cross section of the strip (2), runs at an incline between the two surfaces (15, 16) of the strip (2).

Description

1 Method for the production of a sandwich panel and core material therefor
The invention relates to the production of a core material for sandwich panels. Such a core material preferably consists of strips of fibrous material which are joined to one another at their surfaces with the joins offset turn and turn about. In the expanded state, a pack of strips joined to one another in this way forms a honeycomb-like structure which combines low weight with high rigidity and strength in the finished panel.
In said finished panel the longitudinal edges of the strips are each attached to a cover sheet. The adhesion between the cover sheets and the strips of the core is obtained by means of an adhesive such as, for example, urea formaldehyde adhesive. In connection with keeping the total quantity of adhesive required as low as possible, in the case of cover sheets having a closed surface structure (such as metal or plastic) said adhesive is preferably applied to the longitudinal edges of the strips. Incidentally, in the case of cover sheets which consist of an open structure, such as fibrous material, the adhesive is applied to said cover sheets themselves.
In order to obtain adhesion of the desired strength, it is not only the quality of the adhesive that is important, but also the nature of the surfaces to be joined. The surface area of the longitudinal edges of the strips, which is determined by the cut surface which is the result of cutting off the strips from a sheet, is fairly small. Nevertheless, a certain strength of join can still be achieved because the adhesive forms beads close to the longitudinal edges on both surfaces of the strips, which beads have a beneficial effect on the join. The fact that the material of the strips is fibrous also contributes to the adhesion. The adhesive is able to penetrate into said fibrous material to some extent, as a result of which the strength of the adhesion increases.
In order to improve the absorbent capacity and the surface area of the longitudinal edges available for adhesion, the core material is fed between two rollers, which are optionally provided with a profile. Said rollers roughen the cut surfaces of the strips and as it were make said surfaces open and larger, so that a larger amount of adhesive can be absorbed and the adhesion can be improved.
The aim of the invention is to improve the production of such sandwich panels so that, on the one hand, the production process is simplified and, on the other hand, better adhesion between cover sheets and core material is obtained. 2
Said aim is achieved by means of a method for the production of a core material composed of strips of preferably fibrous material for a sandwich panel, in which sandwich panel the width direction of the strips is coincident with the thickness direction of the panel and a cover layer is attached to each of the longitudinal edges of the strips, comprising cutting each strip from a sheet with the formation of, in each case, a longitudinal edge having a cut surface which, viewed in cross-section of the strip, runs at an incline between the two surfaces of the strip.
With the method according to the invention, the strips which form the core are cut off from a sheet of starting material in such a way that an oblique cut surface is produced. As a consequence of such an oblique cut, the surface area of the cut surface is increased and specifically is increased by a factor of 1/cosα, where α is the acute angle between the cut surface and the thickness direction of the strip.
Said increase in surface area yields a larger surface area of the core available for adhesion to the cover sheets, as a consequence of which the quality of the join is higher. The larger surface area is also able to absorb more adhesive.
The better adhesion is obtained on both longitudinal edges of the strips. Specifically, the strips are cut successively in a continuous process from an even number of sheets of starting material. The angles of the two longitudinal edges of a strip are therefore also complementary. The adhesion of the honeycomb with obliquely cut longitudinal edges can be further improved by a treatment with, for example, rollers, optionally provided with a profile, as a result of which, just as in the case of conventional honeycomb, the cut surfaces are roughened.
According to the invention the angle of the cut surface can be between 20° and 70° with respect to the thickness direction of the strip. Preferably, said angle is approximately 45°.
The invention also relates to a method for the production of a panel from a core material and two cover layers, comprising the steps of production of a core material composed of strips of preferably fibrous material, as described above, application of an adhesive to the longitudinal edges of the strips of the core material and/or to the cover layers and pressing the core material and the cover layers onto one another, during which operation the longitudinal edges are deformed as a consequence of their inclined cut surface, which deformed longitudinal edges provide an enlarged area of adhesion 3 between the core material and the cover layers.
As already mentioned, the oblique shape of the longitudinal edges of the strips in the core leads to an increase in the surface available for adhesion. Said surface available for adhesion is further enlarged as a consequence of the deformation of the longitudinal edges on compressing the pack made up of core and cover sheets. This leads to a further improvement in the adhesion between core and cover sheets.
The invention also relates to a panel as produced according to the method described above.
The invention will now be explained in more detail with reference to an illustrative embodiment shown in the figures.
Figure 1 shows a section of a core material, made up of strips, in the closed form, each strip consisting of an even number of layers.
Figure 2 shows the core material between two cover sheets before fixing to one another. Figure 3 shows a cross-section through a finished panel.
The core material 1 shown in Figure 1 is made up of strips 2, consisting of an even number of layers, which are joined to one another, for example by gluing, at their surfaces 3, 4 facing one another with the joins offset turn and turn about. On expansion of the core material 1, a honeycomb structure is obtained as a consequence of said joins being offset turn and turn about. A honeycomb structure of this type for a core material made up of strips 2 is known and is not further shown.
The strips 2 are cut off obliquely at their longitudinal edges 5, 6. The angle α with respect to their thickness direction 7 can be between 20 and 70°. The angle is preferably 45°. Cover sheets 8, 9 are used to produce a panel from a core material 1. A layer 10 of adhesive is applied to those surfaces of the cover sheets 8, 9 which face one another. The cover sheets 8, 9 can consist of fibrous material, like the strips 2.
The pack made up of cover sheets 8, 9 and strips 2 is then pressed together, as a result of which the oblique cut surfaces 11 are pressed flat as is shown in Figure 3. On said pressing flat, a nose 12 is formed on each strip, as a result of which an enlarged area 13 for adhesion between each strip 2 and the cover sheets 8, 9 is in turn obtained.
Furthermore, a bead 14 of adhesive material is formed on both sides of the surface 4
13, available for adhesion, as a consequence of the adhesive being squeezed out, as a result of which the adhesion between the strips 2 and the cover sheets 8, 9 is further improved.

Claims

5 Claims
1. Method for the production of a core material (1) composed of strips (2) of preferably fibrous material for a sandwich panel, in which sandwich panel the width direction (7) of the strips (2) is coincident with the thickness direction of the panel and a cover layer (8, 9) is attached to each of the longitudinal edges (5, 6) of the strips (2), comprising cutting each strip (2) from an even number of layers with the formation of, in each case, a longitudinal edge (5, 6) having a cut surface (11) which, viewed in cross-section of the strip (2), runs at an incline between the two surfaces (15, 16) of the strip (2).
2. Method according to Claim 1, comprising cutting each strip (2) with the formation of a cut surface (11) at an angle (α) of between 20° and 70° with respect to the thickness direction (7) of the strip (2).
3. Method according to Claim 1, comprising cutting each strip (2) with the formation of a cut surface (11) at an angle (α) of between 30° and 60° with respect to the thickness direction (7) of the strip (2).
4. Method according to Claim 1, comprising cutting each strip (2) with the formation of a cut surface (11) at an angle (α) of between 40° and 50° with respect to the thickness direction (7) of the strip (2).
5. Method according to one of the preceding claims, comprising cutting each strip (2) with the formation of a cut surface (11) at an angle (α) of 45°.
6. Method for the production of a panel from a core material (1) and two cover layers (8, 9), comprising the steps of production of a core material (1) composed of strips (2) of preferably fibrous material, according to one of the preceding claims, application of an adhesive (10) to the longitudinal edges (5, 6) of the strips (2) of the core material (1) and/or to the cover layers (8, 9) and pressing the core material (1) and the cover layers (8, 9) onto one another, during which operation the longitudinal edges (5, 6) are deformed (12) as a consequence of their inclined cut surface (11), which 6 deformed longitudinal edges (5, 6) provide an enlarged area (13) of adhesion between the core material (1) and the cover layers (8, 9).
7. Panel produced according to Claim 6, wherein the core material is roughened using rollers optionally provided with a profile.
8. Panel produced according to the method of Claim 6 or 7.
PCT/NL1999/000040 1998-01-23 1999-01-22 Method for the production of a sandwich panel and core material therefor Ceased WO1999037871A1 (en)

Priority Applications (7)

Application Number Priority Date Filing Date Title
US09/600,855 US6514368B1 (en) 1998-01-23 1999-01-22 Method for the production of a sandwich panel and core material therefor
EP99900723A EP1049838B1 (en) 1998-01-23 1999-01-22 Method for the production of a sandwich panel and core material therefor
DK99900723T DK1049838T3 (en) 1998-01-23 1999-01-22 Process for producing a sandwich panel and core material thereof
AT99900723T ATE260384T1 (en) 1998-01-23 1999-01-22 METHOD FOR PRODUCING A SANDWICH ELEMENT AND CORE MATERIAL THEREFOR
DE69915032T DE69915032T2 (en) 1998-01-23 1999-01-22 METHOD FOR PRODUCING A SANDWICH ELEMENT AND CORE MATERIAL THEREFOR
AU19869/99A AU1986999A (en) 1998-01-23 1999-01-22 Method for the production of a sandwich panel and core material therefor
CA002318873A CA2318873C (en) 1998-01-23 1999-01-22 Method for the production of a sandwich panel and core material therefor

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
NL1008118 1998-01-23
NL1008118A NL1008118C2 (en) 1998-01-23 1998-01-23 Method of manufacturing a sandwich panel and core material therefor.

Publications (1)

Publication Number Publication Date
WO1999037871A1 true WO1999037871A1 (en) 1999-07-29

Family

ID=19766407

Family Applications (1)

Application Number Title Priority Date Filing Date
PCT/NL1999/000040 Ceased WO1999037871A1 (en) 1998-01-23 1999-01-22 Method for the production of a sandwich panel and core material therefor

Country Status (14)

Country Link
US (1) US6514368B1 (en)
EP (1) EP1049838B1 (en)
CN (1) CN1109795C (en)
AT (1) ATE260384T1 (en)
AU (1) AU1986999A (en)
CA (1) CA2318873C (en)
DE (1) DE69915032T2 (en)
DK (1) DK1049838T3 (en)
ES (1) ES2216484T3 (en)
MY (1) MY141666A (en)
NL (1) NL1008118C2 (en)
PL (1) PL199668B1 (en)
PT (1) PT1049838E (en)
WO (1) WO1999037871A1 (en)

Families Citing this family (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US7127865B2 (en) * 2002-10-11 2006-10-31 Douglas Robert B Modular structure for building panels and methods of making and using same
JP4790234B2 (en) * 2004-07-01 2011-10-12 株式会社ニデック Vitreous cutter
CN105332472B (en) * 2015-11-19 2018-01-19 嘉善鸿源蜂窝制品有限公司 The sandwich standard aluminium of honeycomb fashion
NL2027014B1 (en) * 2020-11-30 2022-07-04 Holland Composites Bv Renewable lightweight composite assembly

Citations (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
GB2277709A (en) * 1991-11-07 1994-11-09 Honicel Nederland A Sandwich Panel

Family Cites Families (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2348703A (en) * 1942-04-09 1944-05-09 Francis M Weir Plywood structure
US3483070A (en) * 1968-08-14 1969-12-09 Union Camp Corp Method of sanding honeycomb structure and the sanded article

Patent Citations (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
GB2277709A (en) * 1991-11-07 1994-11-09 Honicel Nederland A Sandwich Panel

Also Published As

Publication number Publication date
DE69915032D1 (en) 2004-04-01
PL341957A1 (en) 2001-05-07
CA2318873C (en) 2007-05-08
PL199668B1 (en) 2008-10-31
ATE260384T1 (en) 2004-03-15
CN1289386A (en) 2001-03-28
PT1049838E (en) 2004-07-30
US6514368B1 (en) 2003-02-04
MY141666A (en) 2010-05-31
DE69915032T2 (en) 2004-09-02
EP1049838A1 (en) 2000-11-08
DK1049838T3 (en) 2004-03-22
CA2318873A1 (en) 1999-07-29
EP1049838B1 (en) 2004-02-25
CN1109795C (en) 2003-05-28
NL1008118C2 (en) 1999-07-26
ES2216484T3 (en) 2004-10-16
AU1986999A (en) 1999-08-09

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