CA2248291C - Structuring process that stiffens and protects the surface of thin material webs - Google Patents
Structuring process that stiffens and protects the surface of thin material webs Download PDFInfo
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- CA2248291C CA2248291C CA002248291A CA2248291A CA2248291C CA 2248291 C CA2248291 C CA 2248291C CA 002248291 A CA002248291 A CA 002248291A CA 2248291 A CA2248291 A CA 2248291A CA 2248291 C CA2248291 C CA 2248291C
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- supporting elements
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- 239000000463 material Substances 0.000 title claims abstract description 121
- 238000000034 method Methods 0.000 title claims description 48
- 239000011888 foil Substances 0.000 claims abstract description 47
- 238000005452 bending Methods 0.000 claims description 9
- 238000003825 pressing Methods 0.000 claims description 6
- 238000007373 indentation Methods 0.000 abstract description 3
- 210000000988 bone and bone Anatomy 0.000 description 8
- 238000004519 manufacturing process Methods 0.000 description 7
- 239000011324 bead Substances 0.000 description 3
- 230000000694 effects Effects 0.000 description 3
- 238000012856 packing Methods 0.000 description 3
- 238000004049 embossing Methods 0.000 description 2
- 238000002474 experimental method Methods 0.000 description 2
- QNRATNLHPGXHMA-XZHTYLCXSA-N (r)-(6-ethoxyquinolin-4-yl)-[(2s,4s,5r)-5-ethyl-1-azabicyclo[2.2.2]octan-2-yl]methanol;hydrochloride Chemical compound Cl.C([C@H]([C@H](C1)CC)C2)CN1[C@@H]2[C@H](O)C1=CC=NC2=CC=C(OCC)C=C21 QNRATNLHPGXHMA-XZHTYLCXSA-N 0.000 description 1
- 230000015572 biosynthetic process Effects 0.000 description 1
- 239000008280 blood Substances 0.000 description 1
- 210000004369 blood Anatomy 0.000 description 1
- 230000003247 decreasing effect Effects 0.000 description 1
- 229920001971 elastomer Polymers 0.000 description 1
- 239000000806 elastomer Substances 0.000 description 1
- 238000005516 engineering process Methods 0.000 description 1
- 238000010297 mechanical methods and process Methods 0.000 description 1
- 230000000704 physical effect Effects 0.000 description 1
- 238000005096 rolling process Methods 0.000 description 1
Classifications
-
- A—HUMAN NECESSITIES
- A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
- A61B—DIAGNOSIS; SURGERY; IDENTIFICATION
- A61B17/00—Surgical instruments, devices or methods, e.g. tourniquets
- A61B17/56—Surgical instruments or methods for treatment of bones or joints; Devices specially adapted therefor
- A61B17/58—Surgical instruments or methods for treatment of bones or joints; Devices specially adapted therefor for osteosynthesis, e.g. bone plates, screws, setting implements or the like
- A61B17/68—Internal fixation devices, including fasteners and spinal fixators, even if a part thereof projects from the skin
- A61B17/80—Cortical plates, i.e. bone plates; Instruments for holding or positioning cortical plates, or for compressing bones attached to cortical plates
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B21—MECHANICAL METAL-WORKING WITHOUT ESSENTIALLY REMOVING MATERIAL; PUNCHING METAL
- B21D—WORKING OR PROCESSING OF SHEET METAL OR METAL TUBES, RODS OR PROFILES WITHOUT ESSENTIALLY REMOVING MATERIAL; PUNCHING METAL
- B21D15/00—Corrugating tubes
- B21D15/04—Corrugating tubes transversely, e.g. helically
- B21D15/10—Corrugating tubes transversely, e.g. helically by applying fluid pressure
- B21D15/105—Corrugating tubes transversely, e.g. helically by applying fluid pressure by applying elastic material
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
- B29C—SHAPING OR JOINING OF PLASTICS; SHAPING OF MATERIAL IN A PLASTIC STATE, NOT OTHERWISE PROVIDED FOR; AFTER-TREATMENT OF THE SHAPED PRODUCTS, e.g. REPAIRING
- B29C49/00—Blow-moulding, i.e. blowing a preform or parison to a desired shape within a mould; Apparatus therefor
-
- A—HUMAN NECESSITIES
- A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
- A61B—DIAGNOSIS; SURGERY; IDENTIFICATION
- A61B17/00—Surgical instruments, devices or methods, e.g. tourniquets
- A61B17/56—Surgical instruments or methods for treatment of bones or joints; Devices specially adapted therefor
- A61B17/58—Surgical instruments or methods for treatment of bones or joints; Devices specially adapted therefor for osteosynthesis, e.g. bone plates, screws, setting implements or the like
- A61B17/68—Internal fixation devices, including fasteners and spinal fixators, even if a part thereof projects from the skin
- A61B17/80—Cortical plates, i.e. bone plates; Instruments for holding or positioning cortical plates, or for compressing bones attached to cortical plates
- A61B17/8085—Cortical plates, i.e. bone plates; Instruments for holding or positioning cortical plates, or for compressing bones attached to cortical plates with pliable or malleable elements or having a mesh-like structure, e.g. small strips
Landscapes
- Health & Medical Sciences (AREA)
- Orthopedic Medicine & Surgery (AREA)
- Engineering & Computer Science (AREA)
- Surgery (AREA)
- Life Sciences & Earth Sciences (AREA)
- Mechanical Engineering (AREA)
- Medical Informatics (AREA)
- General Health & Medical Sciences (AREA)
- Neurology (AREA)
- Fluid Mechanics (AREA)
- Biomedical Technology (AREA)
- Heart & Thoracic Surgery (AREA)
- Physics & Mathematics (AREA)
- Molecular Biology (AREA)
- Animal Behavior & Ethology (AREA)
- Nuclear Medicine, Radiotherapy & Molecular Imaging (AREA)
- Public Health (AREA)
- Veterinary Medicine (AREA)
- Manufacturing & Machinery (AREA)
- Casting Or Compression Moulding Of Plastics Or The Like (AREA)
- Shaping Of Tube Ends By Bending Or Straightening (AREA)
- Treatment Of Fiber Materials (AREA)
- Blow-Moulding Or Thermoforming Of Plastics Or The Like (AREA)
- Treatments For Attaching Organic Compounds To Fibrous Goods (AREA)
Abstract
Curved material webs (1) and foils are supported by hexagonal support elemen ts (3) and subjected to excess or negative pressure. The support elements (3) are dimensioned so that their geometry corresponds to the freely forming indentation folds (5-10).
Description
Process and apparatus for surface-preserving stiffening profiling of thin material sheets Field of the Invention The invention concerns a process and an apparatus for surface-preserving stiffening profiling of thin material sheets or foils in which curved material sheets or foils are supported on supporting elements and pressurized with excess or negative pressure.
Background Numerous deformation methods are known for stiffening thin material sheets and foils by profiling, among them deep-drawing, pressing and rolling with form tools such as molds and shape rolls. The drawback of these deformation technologies is that the mechanical surface pressure strongly plastifies the material sheets and foils to be profiled and degrades their surface quality.
The European patent application 0 441 618 A 1 describes a process in which polyhedral structures such as rhombic and hexagonal profiles are produced with the aid of two embossing rolls. Owing to the strong mechanical deformation, this purely mechanical forming process considerably degrades the surface quality of the materials.
US patent no. 4,576,669 suggests to feed plastic foil over a roll that carries small cups into which the plastic foil is sucked by vacuum pressure. Thus the cross-section of the foil is reduced, cracks can occur, and the inherent stability of the foil is not noticeably enhanced. Also, a device is known which serves to emboss axial beads into cans by supporting the cans on axial, rigid elements from the inside and pressurizing the outside by means of an elastic roller (DE 35 87 768 T 2). However, the inherent stability of the material furnished with axial beads in this way is insufficient because, for geometric reasons, beads do not yield multi-dimensional inherent stability. A process in which round, dome shaped structures are impressed in a foil by means of a perforated, cylindrical form tool and an elastic press roller also leads to a reduced cross-section of the foil and does not, or only very slightly, improve inherent stability because large regions remain undeformed between the round, dome shaped structures (French application no. 1,283,530).
Furthermore, a process is known in which thin material sheets or foils are profiled dent-like. In the process, the curved thin material sheet or foil is supported by line shaped supporting elements on the inside, and hydraulically pressurized from the outside. Offset quadrangular dent structures result that considerably improve the inherent stability of the material sheet (Deutsche Offenlegungsschrift 25 57 2I5 [Patent Application Published on June 23, 1977], German printed patent specification DE 43 11 978). In principle, this dent-profiling process differs from the one described in application no. 0 441 618 A 1 in that not two mechanically acting embossing rollers are required but only a core with line shaped supporting elements on which the material sheet rests and against which it is hydraulically pressed. The curved material sheet which is supported on the inside by supporting elements arranged at intervals (rings or helix) becomes unstable due to the outside pressure. The instability results in mufti-dimensional folding, and consequently offset quadrangular dent profiles form in a self-organizing process with the dent troughs evolving by themselves. As the material is only slightly stretched and upset in this process, the surface quality of the material is not, or only very slightly, degraded. However, this offset quadrangular profiled material sheet (see Fig. 2 in DE 43 11 978) has no isotropic inherent stability in the plain because it is flexibly perpendicular to the continuous dent folds, and dimensionally stable parallel to these folds. An almost isotropic inherent stability is achieved by a process in which hexagonal dent profiles are produced (published international patent application PCT/EP 94/01043, Fig. 5 b and 5 c). Instead of hydraulical pressure, an unprofiled, elastic cushion or an unprofiled elastomer can be used for pressurization. The supporting elements against which the material sheet is pressed are made of a flexible material which is either fixed or movable on the core.
However, the hexagonal structures thus produced are not uniform.
All known profiling processes that use form tools have the essential disadvantages that the material is severely plastified, that in deep-drawing the wall thickness of the material sheet is decreased and the material can tear, that in deep-drawing Baring of the material sheet can occur, and that the surface quality of the material is degraded due to the pressure on the surface by the form tools and the severe plastification. At a given spatial depth of structure these conventional, purely mechanical, profiling methods result in a high degree of plastic deformation of the material which degrades the surface quality of the material.
Another essential drawback of the hydraulic profiling processes described in OS 25 57 215, DE 43 11 978, and PCT/EP 94/01043, is that although the degree of plastic deformation is lower than with the purely mechanical methods and the surface quality of the material is not degraded, the structures produced are not regular. The reasons for that . 30672-2 are, among others, inevitable material non-homogeneity, wall thickness tolerances of the material to be processed, and the not absolutely even pressurization of the material sheet.
Summary of the Invention According to one aspect of the present invention, there is provided a process for surface-preserving stiffening profiling of thin material sheets and foils in which the curved material sheets and foils are supported by supporting elements and pressurized with excess or negative pressure, the process comprising; using rigid quadrangular or hexagonal supporting elements; pressurizing the curved material sheet from the outside by elastic, unprofiled elements; pressurizing the material sheet in its curvature;
and designing the supporting elements so that their shapes correspond to the dent folds that evolve by themselves.
In accordance with a second aspect of the present invention, there is provided a process for stiffening profiling of thin materials and foils in which a curved material or foil is supported by rigid quadrangular or hexagonal supporting elements arranged on a mechanical forming tool and pressurized against said supporting elements, wherein said curved material or foil is pressurized on the side opposite said supporting elements, by an elastic flexible element so that said material or foil is pressurized in its curvature wherein dent folds which correspond to the shape of said supporting elements evolve by themselves in said material or foil by said dent folds springing and evolving into their final shape in said material or foil by partly or completely bending dent troughs without said dent troughs associated with said dent folds being touched by said mechanical forming tool, thereby producing a stiffened thin material or foil.
In accordance with a third aspect of the present invention, there is provided a process for stiffening profiling a thin material to form a curved material, said process comprising the steps of: equipping a roller with rigid supporting elements; feeding said thin material between said roller and a flexible press roller such that said thin material is supported by said rigid supporting elements; and applying pressure to said thin material against said rigid supporting elements using said flexible press roller, thus pressing said material against said rigid supporting elements, wherein dent folds having a shape corresponding to said supporting elements, thereby evolve by themselves in said thin material by said dent folds springing and evolving into their final shape by partly or completely bending dent troughs without dent troughs associated with said folds being touched by said roller with rigid supporting elements and wherein a stiffened thin curved material is produced.
In accordance with a fourth aspect of the present invention, there is provided a process for stiffening profiling a thin, curved material or foil while preserving a surface of said thin material or foil, said process comprising the steps of: equipping a roller with rigid supporting elements; covering said rigid supporting elements by a flexible layer; feeding said thin, curved material between said roller and a flexible unprofiled press roller such that said thin, curved material is supported by said rigid supporting elements and said flexible layer; and pressurizing said thin material against said rigid supporting elements and said flexible layer by said flexible unprofiled roller; wherein dent folds having a shape . 30672-2 corresponding to said supporting elements evolve by themselves in said material or foil by said dent folds springing and evolving into their final shape in said material or foil by partly or completely bending dent troughs without said dent troughs associated with said dent folds being touched by said roller with rigid supporting elements, thereby producing a stiffened thin material or foil.
Embodiments of the invention provide a profiling process which allows for the material sheet to be profiled so that the surface is minimally affected and only slight plastic deformation of the material occurs, and yet uniform three-dimensional structuring takes place. Additionally, the invention allows for an improved inherent stability in the plain of the profiled material sheet to be achieved while only minimally affecting the cross-section.
According to embodiments of the present invention, these achievements are made by pressurizing a curved material sheet from the outside via elastic, unstructured elements pressing it against rigid, quadrangular or hexagonal supporting elements which are arranged so that their shapes correspond with the dent folds that evolve by self-organization. This process is basically different from all known, purely mechanical, profiling methods because the dents spring into their final shape in the material sheet and no contact with the mechanical form tool against which they are pressed takes place. The improved inherent stability by dent-profiling results from the formation of dents that adopt their spatial, dimensionally stable dome shape on their own. Experiments have again and again proved this effect. In embodiments of the process according to the invention, the geometry of the rigid, quadrangular or hexagonal supporting elements corresponds to the dents that evolve by self-organization. In this material-preserving way, regularly arranged structures are produced because by presetting the optimized quadrangular or hexagonal supporting elements. The negative effects (non-homogeneity and wall thickness tolerances of the material to be processed, uneven pressurization, etc.) are compensated and the advantages of the surface-preserving and stiffening dent-profiling process with slight plastification of the material are fully made use of.
An embodiment of the invention uses an additional flexible layer between the material sheet to be profiled and the supporting elements to buffer any undesired mechanical imprints made by the supporting elements in a material sheet with a sensitive surface. The resulting dent profiles are flatter with this additional layer than without it. There is another advantage gained by the flexible layer:
experiments have shown that when dents form freely during the indentation process, preferably hexagonal structures evolve if the material sheet is pressed against a core with quadrangular supporting elements and a flexible layer is placed between material sheet and supporting elements. The advantage of this method, with respect to engineering and costs, is that quadrangular elements are cheaper and simpler to produce than hexagonal ones, and that material sheets with a highly sensitive surface can be structured particularly carefully. However, because, as a consequence of the buffer effect of the flexible layer, the depth of the dents is lower than without it, and the inherent stability achieved is also reduced.
Another embodiment of the invention allows for dent-profiled material sheets or foils to be shaped into spatial shells without complicated form tools being required. To achieve this, material sheets or foils profiled with hexagonal dents are shaped in several dimensions by bending the dent folds of the hexagonal structures deeper where the local radius of curvature of the component is to be increased, and by completely or partly bending them up where the local radius of curvature of the component is to be flatter. Just slight plastification of the material occurs in this bending of the structure folds.
Brief Description of the Drawings Examples of embodiments of the invention will now be described with reference to the drawings, in which:
Fig. 1 is a diagrammatic view of the design of a device for manufacturing material sheets or foils using a roller on which supporting elements are arranged and a flexible press roller (radial cross-section).
Fig. lA is a magnification of the design indicated by the circle A in Fig. 1.
Fig. 2 is an illustration aspect of a dent structure produced by a device according to Fig. 1 equipped with offset quadrangular supporting elements.
Fig. 3 and 4 are illustrations of aspects of two dent structures produced by a device according to Fig. 1 equipped with two different hexagonal supporting elements.
Fig. 5 is a diagrammatic view of the design of a device for manufacturing dent-profiled material sheets by means of a roll on which supporting elements are arranged, a flexible press roller, and an additional flexible layer.
Fig. 6 is a diagrammatic view of the design of a device for manufacturing dent-profiled cans by means of a roll on which supporting elements are arranged and a flexible press roller (radial cross-section).
Fig. 7 is a diagrammatic view of the design of a device for manufacturing dent-profiled cans by means of a roll on which supporting elements are arranged (axial aspect) and a flexible press roller (axial cross-section).
Fig. 8 and 9 are diagrammatic views of a dent-profiled cylindrical container with globular tower packing (Fig. 8, radial cross-section; Fig. 9, axial cross-section).
Fig. 10 and 11 are diagrammatic views of a dent-profiled material sheet (splint) for confining and supporting two bones (Fig. 10, axial cross-section; Fig. 11, radial cross-section).
Detailed Description The device depicted in Figs. 1 and lA shows the elementary design of a device for manufacturing dent-profiled material sheets or foils. The material sheet 1 is fed around the roller 2 on which the supporting elements 3 are arranged, and pressed against the supporting elements 3 by the flexible press roller 4. The pressure put on the curved material sheet 1 by the flexible press roller 4 results in indentation of the material sheet 1 between the supporting elements 3, by which process the dents spring into their final shape without the dent troughs being touched by the mechanical form.
The aspects depicted in Fig. 2, 3, and 4 are unwound dent-profiled material sheets produced by means of a device according to Fig. 1. Fig. 2 depicts offset quadrangles resulting from the dent folds 5 (in material sheet feed direction) at a distance h between each other and the dent folds 6 (perpendicular to material sheet feed direction) at a distance b between each other. Fig. 3 and 4 depict aspects of two alternative arrangements of hexagonal structures. In Fig. 3, the dent folds 7 (in material sheet feed direction) are zigzag shaped and are at a distance h between each other. The dent folds 8 (perpendicular to material sheet feed direction) are at a distance b between each other. In Fig. 4, the dent folds 9 (perpendicular to material sheet feed direction) are zigzag shaped. The dent folds 10 (in material sheet feed direction) are at a distance h between each other.
The device depicted in Fig. 5 shows the schematic design of a device for manufacturing dent-profiled material sheets or foils by means of a flexible press roller 4 and a roller 2 on which supporting elements 3 are arranged that are covered by an additional flexible material sheet 11.
Thus, undesired mechanical imprints caused by possible irregularities of the supporting contours 3 are equalized.
Figs. 6 and 7 schematically depict the manufacture of dent-profiled cans or thin-walled cylinders. Fig. 6 depicts the radial cross-section of the device with the roller 2 on which the supporting elements 3 are arranged, the flexible press roller 4, and the cylindrical can body or cylindrical wall 12. Fig. 7 depicts the components mentioned in axial view.
Figs. 8 and 9 schematically depict the radial cross-section (Fig. 8) and the axial cross-section (Fig. 9) of a dent-profiled cylindrical container 13 filled with tower packing 14. The dent structures of the container wall 13 are adapted to the curvatures of the balls of the tower packing 14 so that the free cross-section of flow between the balls 14 close to the wall and the dent-profiled container wall 13 is low.
In Fig. 10 and 11, the radial cross-section (Fig. 10) and the axial cross-section (Fig. 11) of a dent profiled material sheet 15 which confines and splints two pieces of bone 16 is depicted schematically. The shell shaped dent-profiled material sheet 15 is bent around the pieces of bone 16 and touches the two pieces of bone only with the troughs of its dents. Thus, the periost surrounding the bone is highly stressed only at the small contact surfaces between the dent troughs and the bone. In between these contact surfaces, the periost continues to be supplied with blood and consequently does not die off.
Additionally, the shell shape dent-profiled splint has a higher inherent stability than the conventional smooth splints because, compared to a non-profiled splint of the same material and with the same dimensions, it possesses better flexural strength in the radial direction and higher elasticity in the direction of the bone. Therefore, the dent-profiled splint adjusts better to the physical properties of the bone than a conventional smooth splint.
Background Numerous deformation methods are known for stiffening thin material sheets and foils by profiling, among them deep-drawing, pressing and rolling with form tools such as molds and shape rolls. The drawback of these deformation technologies is that the mechanical surface pressure strongly plastifies the material sheets and foils to be profiled and degrades their surface quality.
The European patent application 0 441 618 A 1 describes a process in which polyhedral structures such as rhombic and hexagonal profiles are produced with the aid of two embossing rolls. Owing to the strong mechanical deformation, this purely mechanical forming process considerably degrades the surface quality of the materials.
US patent no. 4,576,669 suggests to feed plastic foil over a roll that carries small cups into which the plastic foil is sucked by vacuum pressure. Thus the cross-section of the foil is reduced, cracks can occur, and the inherent stability of the foil is not noticeably enhanced. Also, a device is known which serves to emboss axial beads into cans by supporting the cans on axial, rigid elements from the inside and pressurizing the outside by means of an elastic roller (DE 35 87 768 T 2). However, the inherent stability of the material furnished with axial beads in this way is insufficient because, for geometric reasons, beads do not yield multi-dimensional inherent stability. A process in which round, dome shaped structures are impressed in a foil by means of a perforated, cylindrical form tool and an elastic press roller also leads to a reduced cross-section of the foil and does not, or only very slightly, improve inherent stability because large regions remain undeformed between the round, dome shaped structures (French application no. 1,283,530).
Furthermore, a process is known in which thin material sheets or foils are profiled dent-like. In the process, the curved thin material sheet or foil is supported by line shaped supporting elements on the inside, and hydraulically pressurized from the outside. Offset quadrangular dent structures result that considerably improve the inherent stability of the material sheet (Deutsche Offenlegungsschrift 25 57 2I5 [Patent Application Published on June 23, 1977], German printed patent specification DE 43 11 978). In principle, this dent-profiling process differs from the one described in application no. 0 441 618 A 1 in that not two mechanically acting embossing rollers are required but only a core with line shaped supporting elements on which the material sheet rests and against which it is hydraulically pressed. The curved material sheet which is supported on the inside by supporting elements arranged at intervals (rings or helix) becomes unstable due to the outside pressure. The instability results in mufti-dimensional folding, and consequently offset quadrangular dent profiles form in a self-organizing process with the dent troughs evolving by themselves. As the material is only slightly stretched and upset in this process, the surface quality of the material is not, or only very slightly, degraded. However, this offset quadrangular profiled material sheet (see Fig. 2 in DE 43 11 978) has no isotropic inherent stability in the plain because it is flexibly perpendicular to the continuous dent folds, and dimensionally stable parallel to these folds. An almost isotropic inherent stability is achieved by a process in which hexagonal dent profiles are produced (published international patent application PCT/EP 94/01043, Fig. 5 b and 5 c). Instead of hydraulical pressure, an unprofiled, elastic cushion or an unprofiled elastomer can be used for pressurization. The supporting elements against which the material sheet is pressed are made of a flexible material which is either fixed or movable on the core.
However, the hexagonal structures thus produced are not uniform.
All known profiling processes that use form tools have the essential disadvantages that the material is severely plastified, that in deep-drawing the wall thickness of the material sheet is decreased and the material can tear, that in deep-drawing Baring of the material sheet can occur, and that the surface quality of the material is degraded due to the pressure on the surface by the form tools and the severe plastification. At a given spatial depth of structure these conventional, purely mechanical, profiling methods result in a high degree of plastic deformation of the material which degrades the surface quality of the material.
Another essential drawback of the hydraulic profiling processes described in OS 25 57 215, DE 43 11 978, and PCT/EP 94/01043, is that although the degree of plastic deformation is lower than with the purely mechanical methods and the surface quality of the material is not degraded, the structures produced are not regular. The reasons for that . 30672-2 are, among others, inevitable material non-homogeneity, wall thickness tolerances of the material to be processed, and the not absolutely even pressurization of the material sheet.
Summary of the Invention According to one aspect of the present invention, there is provided a process for surface-preserving stiffening profiling of thin material sheets and foils in which the curved material sheets and foils are supported by supporting elements and pressurized with excess or negative pressure, the process comprising; using rigid quadrangular or hexagonal supporting elements; pressurizing the curved material sheet from the outside by elastic, unprofiled elements; pressurizing the material sheet in its curvature;
and designing the supporting elements so that their shapes correspond to the dent folds that evolve by themselves.
In accordance with a second aspect of the present invention, there is provided a process for stiffening profiling of thin materials and foils in which a curved material or foil is supported by rigid quadrangular or hexagonal supporting elements arranged on a mechanical forming tool and pressurized against said supporting elements, wherein said curved material or foil is pressurized on the side opposite said supporting elements, by an elastic flexible element so that said material or foil is pressurized in its curvature wherein dent folds which correspond to the shape of said supporting elements evolve by themselves in said material or foil by said dent folds springing and evolving into their final shape in said material or foil by partly or completely bending dent troughs without said dent troughs associated with said dent folds being touched by said mechanical forming tool, thereby producing a stiffened thin material or foil.
In accordance with a third aspect of the present invention, there is provided a process for stiffening profiling a thin material to form a curved material, said process comprising the steps of: equipping a roller with rigid supporting elements; feeding said thin material between said roller and a flexible press roller such that said thin material is supported by said rigid supporting elements; and applying pressure to said thin material against said rigid supporting elements using said flexible press roller, thus pressing said material against said rigid supporting elements, wherein dent folds having a shape corresponding to said supporting elements, thereby evolve by themselves in said thin material by said dent folds springing and evolving into their final shape by partly or completely bending dent troughs without dent troughs associated with said folds being touched by said roller with rigid supporting elements and wherein a stiffened thin curved material is produced.
In accordance with a fourth aspect of the present invention, there is provided a process for stiffening profiling a thin, curved material or foil while preserving a surface of said thin material or foil, said process comprising the steps of: equipping a roller with rigid supporting elements; covering said rigid supporting elements by a flexible layer; feeding said thin, curved material between said roller and a flexible unprofiled press roller such that said thin, curved material is supported by said rigid supporting elements and said flexible layer; and pressurizing said thin material against said rigid supporting elements and said flexible layer by said flexible unprofiled roller; wherein dent folds having a shape . 30672-2 corresponding to said supporting elements evolve by themselves in said material or foil by said dent folds springing and evolving into their final shape in said material or foil by partly or completely bending dent troughs without said dent troughs associated with said dent folds being touched by said roller with rigid supporting elements, thereby producing a stiffened thin material or foil.
Embodiments of the invention provide a profiling process which allows for the material sheet to be profiled so that the surface is minimally affected and only slight plastic deformation of the material occurs, and yet uniform three-dimensional structuring takes place. Additionally, the invention allows for an improved inherent stability in the plain of the profiled material sheet to be achieved while only minimally affecting the cross-section.
According to embodiments of the present invention, these achievements are made by pressurizing a curved material sheet from the outside via elastic, unstructured elements pressing it against rigid, quadrangular or hexagonal supporting elements which are arranged so that their shapes correspond with the dent folds that evolve by self-organization. This process is basically different from all known, purely mechanical, profiling methods because the dents spring into their final shape in the material sheet and no contact with the mechanical form tool against which they are pressed takes place. The improved inherent stability by dent-profiling results from the formation of dents that adopt their spatial, dimensionally stable dome shape on their own. Experiments have again and again proved this effect. In embodiments of the process according to the invention, the geometry of the rigid, quadrangular or hexagonal supporting elements corresponds to the dents that evolve by self-organization. In this material-preserving way, regularly arranged structures are produced because by presetting the optimized quadrangular or hexagonal supporting elements. The negative effects (non-homogeneity and wall thickness tolerances of the material to be processed, uneven pressurization, etc.) are compensated and the advantages of the surface-preserving and stiffening dent-profiling process with slight plastification of the material are fully made use of.
An embodiment of the invention uses an additional flexible layer between the material sheet to be profiled and the supporting elements to buffer any undesired mechanical imprints made by the supporting elements in a material sheet with a sensitive surface. The resulting dent profiles are flatter with this additional layer than without it. There is another advantage gained by the flexible layer:
experiments have shown that when dents form freely during the indentation process, preferably hexagonal structures evolve if the material sheet is pressed against a core with quadrangular supporting elements and a flexible layer is placed between material sheet and supporting elements. The advantage of this method, with respect to engineering and costs, is that quadrangular elements are cheaper and simpler to produce than hexagonal ones, and that material sheets with a highly sensitive surface can be structured particularly carefully. However, because, as a consequence of the buffer effect of the flexible layer, the depth of the dents is lower than without it, and the inherent stability achieved is also reduced.
Another embodiment of the invention allows for dent-profiled material sheets or foils to be shaped into spatial shells without complicated form tools being required. To achieve this, material sheets or foils profiled with hexagonal dents are shaped in several dimensions by bending the dent folds of the hexagonal structures deeper where the local radius of curvature of the component is to be increased, and by completely or partly bending them up where the local radius of curvature of the component is to be flatter. Just slight plastification of the material occurs in this bending of the structure folds.
Brief Description of the Drawings Examples of embodiments of the invention will now be described with reference to the drawings, in which:
Fig. 1 is a diagrammatic view of the design of a device for manufacturing material sheets or foils using a roller on which supporting elements are arranged and a flexible press roller (radial cross-section).
Fig. lA is a magnification of the design indicated by the circle A in Fig. 1.
Fig. 2 is an illustration aspect of a dent structure produced by a device according to Fig. 1 equipped with offset quadrangular supporting elements.
Fig. 3 and 4 are illustrations of aspects of two dent structures produced by a device according to Fig. 1 equipped with two different hexagonal supporting elements.
Fig. 5 is a diagrammatic view of the design of a device for manufacturing dent-profiled material sheets by means of a roll on which supporting elements are arranged, a flexible press roller, and an additional flexible layer.
Fig. 6 is a diagrammatic view of the design of a device for manufacturing dent-profiled cans by means of a roll on which supporting elements are arranged and a flexible press roller (radial cross-section).
Fig. 7 is a diagrammatic view of the design of a device for manufacturing dent-profiled cans by means of a roll on which supporting elements are arranged (axial aspect) and a flexible press roller (axial cross-section).
Fig. 8 and 9 are diagrammatic views of a dent-profiled cylindrical container with globular tower packing (Fig. 8, radial cross-section; Fig. 9, axial cross-section).
Fig. 10 and 11 are diagrammatic views of a dent-profiled material sheet (splint) for confining and supporting two bones (Fig. 10, axial cross-section; Fig. 11, radial cross-section).
Detailed Description The device depicted in Figs. 1 and lA shows the elementary design of a device for manufacturing dent-profiled material sheets or foils. The material sheet 1 is fed around the roller 2 on which the supporting elements 3 are arranged, and pressed against the supporting elements 3 by the flexible press roller 4. The pressure put on the curved material sheet 1 by the flexible press roller 4 results in indentation of the material sheet 1 between the supporting elements 3, by which process the dents spring into their final shape without the dent troughs being touched by the mechanical form.
The aspects depicted in Fig. 2, 3, and 4 are unwound dent-profiled material sheets produced by means of a device according to Fig. 1. Fig. 2 depicts offset quadrangles resulting from the dent folds 5 (in material sheet feed direction) at a distance h between each other and the dent folds 6 (perpendicular to material sheet feed direction) at a distance b between each other. Fig. 3 and 4 depict aspects of two alternative arrangements of hexagonal structures. In Fig. 3, the dent folds 7 (in material sheet feed direction) are zigzag shaped and are at a distance h between each other. The dent folds 8 (perpendicular to material sheet feed direction) are at a distance b between each other. In Fig. 4, the dent folds 9 (perpendicular to material sheet feed direction) are zigzag shaped. The dent folds 10 (in material sheet feed direction) are at a distance h between each other.
The device depicted in Fig. 5 shows the schematic design of a device for manufacturing dent-profiled material sheets or foils by means of a flexible press roller 4 and a roller 2 on which supporting elements 3 are arranged that are covered by an additional flexible material sheet 11.
Thus, undesired mechanical imprints caused by possible irregularities of the supporting contours 3 are equalized.
Figs. 6 and 7 schematically depict the manufacture of dent-profiled cans or thin-walled cylinders. Fig. 6 depicts the radial cross-section of the device with the roller 2 on which the supporting elements 3 are arranged, the flexible press roller 4, and the cylindrical can body or cylindrical wall 12. Fig. 7 depicts the components mentioned in axial view.
Figs. 8 and 9 schematically depict the radial cross-section (Fig. 8) and the axial cross-section (Fig. 9) of a dent-profiled cylindrical container 13 filled with tower packing 14. The dent structures of the container wall 13 are adapted to the curvatures of the balls of the tower packing 14 so that the free cross-section of flow between the balls 14 close to the wall and the dent-profiled container wall 13 is low.
In Fig. 10 and 11, the radial cross-section (Fig. 10) and the axial cross-section (Fig. 11) of a dent profiled material sheet 15 which confines and splints two pieces of bone 16 is depicted schematically. The shell shaped dent-profiled material sheet 15 is bent around the pieces of bone 16 and touches the two pieces of bone only with the troughs of its dents. Thus, the periost surrounding the bone is highly stressed only at the small contact surfaces between the dent troughs and the bone. In between these contact surfaces, the periost continues to be supplied with blood and consequently does not die off.
Additionally, the shell shape dent-profiled splint has a higher inherent stability than the conventional smooth splints because, compared to a non-profiled splint of the same material and with the same dimensions, it possesses better flexural strength in the radial direction and higher elasticity in the direction of the bone. Therefore, the dent-profiled splint adjusts better to the physical properties of the bone than a conventional smooth splint.
Claims (12)
1. A process for surface-preserving stiffening profiling of thin material sheets and foils in which the curved material sheets and foils are supported by supporting elements and pressurized with excess or negative pressure, the process comprising:
using rigid quadrangular or hexagonal supporting elements;
pressurizing the curved material sheet from the outside by elastic, unprofiled elements;
pressurizing the material sheet in its curvature;
and designing the supporting elements so that their shapes correspond to the dent folds that evolve by themselves.
using rigid quadrangular or hexagonal supporting elements;
pressurizing the curved material sheet from the outside by elastic, unprofiled elements;
pressurizing the material sheet in its curvature;
and designing the supporting elements so that their shapes correspond to the dent folds that evolve by themselves.
2. A process according to claim 1, wherein an additional flexible layer is located between the supporting elements and the material sheet to be profiled.
3. A process for stiffening profiling of thin materials and foils in which a curved material or foil is supported by rigid quadrangular or hexagonal supporting elements arranged on a mechanical forming tool and pressurized against said supporting elements, wherein said curved material or foil is pressurized on the side opposite said supporting elements, by an elastic flexible element so that said material or foil is pressurized in its curvature wherein dent folds which correspond to the shape of said supporting elements evolve by themselves in said material or foil by said dent folds springing and evolving into their final shape in said material or foil by partly or completely bending dent troughs without said dent troughs associated with said dent folds being touched by said mechanical forming tool, thereby producing a stiffened thin material or foil.
4. The process according to claim 3 wherein an additional flexible layer is located between the supporting elements and the material to be profiled.
5. A process for stiffening profiling a thin material to form a curved material, said process comprising the steps of:
equipping a roller with rigid supporting elements;
feeding said thin material between said roller and a flexible press roller such that said thin material is supported by said rigid supporting elements; and applying pressure to said thin material against said rigid supporting elements using said flexible press roller, thus pressing said material against said rigid supporting elements, wherein dent folds having a shape corresponding to said supporting elements, thereby evolve by themselves in said thin material by said dent folds springing and evolving into their final shape by partly or completely bending dent troughs without dent troughs associated with said folds being touched by said roller with rigid supporting elements and wherein a stiffened thin curved material is produced.
equipping a roller with rigid supporting elements;
feeding said thin material between said roller and a flexible press roller such that said thin material is supported by said rigid supporting elements; and applying pressure to said thin material against said rigid supporting elements using said flexible press roller, thus pressing said material against said rigid supporting elements, wherein dent folds having a shape corresponding to said supporting elements, thereby evolve by themselves in said thin material by said dent folds springing and evolving into their final shape by partly or completely bending dent troughs without dent troughs associated with said folds being touched by said roller with rigid supporting elements and wherein a stiffened thin curved material is produced.
6. The process according to claim 5, wherein said process comprises a surface preserving process, and wherein said elastic flexible element comprises an elastic unprofiled element.
7. The process of claim 5 wherein said supporting elements are quadrangular supporting elements.
8. The process of claim 5 wherein said supporting elements are hexagonal supporting elements.
9. A process for stiffening profiling a thin, curved material or foil while preserving a surface of said thin material or foil, said process comprising the steps of:
equipping a roller with rigid supporting elements;
covering said rigid supporting elements by a flexible layer;
feeding said thin, curved material between said roller and a flexible unprofiled press roller such that said thin, curved material is supported by said rigid supporting elements and said flexible layer; and pressurizing said thin material against said rigid supporting elements and said flexible layer by said flexible unprofiled roller;
wherein dent folds having a shape corresponding to said supporting elements evolve by themselves in said material or foil by said dent folds springing and evolving into their final shape in said material or foil by partly or completely bending dent troughs without said dent troughs associated with said dent folds being touched by said roller with rigid supporting elements, thereby producing a stiffened thin material or foil.
equipping a roller with rigid supporting elements;
covering said rigid supporting elements by a flexible layer;
feeding said thin, curved material between said roller and a flexible unprofiled press roller such that said thin, curved material is supported by said rigid supporting elements and said flexible layer; and pressurizing said thin material against said rigid supporting elements and said flexible layer by said flexible unprofiled roller;
wherein dent folds having a shape corresponding to said supporting elements evolve by themselves in said material or foil by said dent folds springing and evolving into their final shape in said material or foil by partly or completely bending dent troughs without said dent troughs associated with said dent folds being touched by said roller with rigid supporting elements, thereby producing a stiffened thin material or foil.
10. The process of claim 9 wherein said supporting elements are quadrangular supporting elements.
11. The process of claim 9 wherein said supporting elements are hexagonal supporting elements.
12. The process according to claim 9, wherein said supporting elements are quadrangular and said shapes formed in said thin material or foil are hexagonal.
Priority Applications (7)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CA002248291A CA2248291C (en) | 1996-04-18 | 1996-04-18 | Structuring process that stiffens and protects the surface of thin material webs |
| PL96329310A PL181398B1 (en) | 1996-04-18 | 1996-04-18 | Method of structuring thin material web in a manner ensuring surface protection and increasing rigidity of such web |
| EP96914934A EP0900131B1 (en) | 1996-04-18 | 1996-04-18 | Structuring process that stiffens and embellishes the surface of thin material webs |
| CN96180259A CN1076229C (en) | 1996-04-18 | 1996-04-18 | Structuring process that stiffens and protects surface of thin material webs |
| CZ983334A CZ333498A3 (en) | 1996-04-18 | 1996-04-18 | Process of surface friendly, reinforcing structuring of thin strips of material |
| PCT/EP1996/001608 WO1997039846A1 (en) | 1996-04-18 | 1996-04-18 | Structuring process that stiffens and protects the surface of thin material webs |
| HU9900710A HUP9900710A3 (en) | 1996-04-18 | 1996-04-18 | Structuring process that stiffens and protects the surface of thin material webs |
Applications Claiming Priority (5)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CA002248291A CA2248291C (en) | 1996-04-18 | 1996-04-18 | Structuring process that stiffens and protects the surface of thin material webs |
| PL96329310A PL181398B1 (en) | 1996-04-18 | 1996-04-18 | Method of structuring thin material web in a manner ensuring surface protection and increasing rigidity of such web |
| CN96180259A CN1076229C (en) | 1996-04-18 | 1996-04-18 | Structuring process that stiffens and protects surface of thin material webs |
| PCT/EP1996/001608 WO1997039846A1 (en) | 1996-04-18 | 1996-04-18 | Structuring process that stiffens and protects the surface of thin material webs |
| HU9900710A HUP9900710A3 (en) | 1996-04-18 | 1996-04-18 | Structuring process that stiffens and protects the surface of thin material webs |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CA2248291A1 CA2248291A1 (en) | 1997-10-30 |
| CA2248291C true CA2248291C (en) | 2007-03-13 |
Family
ID=89997973
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CA002248291A Expired - Lifetime CA2248291C (en) | 1996-04-18 | 1996-04-18 | Structuring process that stiffens and protects the surface of thin material webs |
Country Status (6)
| Country | Link |
|---|---|
| EP (1) | EP0900131B1 (en) |
| CN (1) | CN1076229C (en) |
| CA (1) | CA2248291C (en) |
| CZ (1) | CZ333498A3 (en) |
| HU (1) | HUP9900710A3 (en) |
| PL (1) | PL181398B1 (en) |
Families Citing this family (23)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| DE102004044550B4 (en) * | 2004-09-15 | 2006-11-30 | Dr. Mirtsch Gmbh | Process for honeycomb-structured, energy-absorbing reinforcing and crumple shell for shell-shaped body parts for the protection of pedestrians |
| DE102004044509B4 (en) * | 2004-09-15 | 2007-10-04 | Dr. Mirtsch Gmbh | Method for joining and stabilizing thermally and mechanically loaded, thin walls with a flat frame |
| EP1760216A3 (en) | 2005-09-01 | 2007-05-30 | Dr. Mirtsch GmbH | Structured material web made from a web material and method of making |
| DE102006002669B4 (en) * | 2006-01-19 | 2010-04-01 | Dr. Mirtsch Gmbh | Multi-dimensionally structured sliding and skateboard |
| DE102006055657A1 (en) | 2006-11-23 | 2008-05-29 | Behrens, Arno, W. Dr.-Ing. | Component of a flat material and method for its production |
| DE102006062189B4 (en) | 2006-12-22 | 2009-03-19 | Dr. Mirtsch Gmbh | Method for producing a structured material web for the passage of fluid media, structured material web and use thereof |
| KR101136863B1 (en) | 2007-02-28 | 2012-04-20 | 삼성전자주식회사 | Washing machine |
| DE102008056500A1 (en) | 2008-11-08 | 2010-05-12 | Innova-Paper-Form Gmbh | Material sheet e.g. web material, structuring method for calender, involves bringing material sheet into horizontal shape by breaker rollers after leaving structured roller gap, which is formed by stamping and counter-pressure rollers |
| DE102009049573B4 (en) | 2009-10-15 | 2013-03-14 | Dr. Mirtsch Gmbh | Method for producing a structured material web with bevelled partial areas, bent-off, structured material web produced according to the method and use thereof |
| DE102009051603B4 (en) | 2009-11-02 | 2011-09-22 | Dr. Mirtsch Gmbh | A method of producing a structured pipe, structured product produced by the method and use thereof |
| DE102009058098B4 (en) | 2009-12-12 | 2012-08-16 | Dr. Mirtsch Gmbh | Structured belt conveyor |
| DE102010034076B3 (en) * | 2010-08-12 | 2011-12-22 | Dr. Mirtsch Gmbh | Method for producing a structured, straight or one- or two-dimensionally curved material web / profile, associated / associated three-dimensionally structured / structured, straight / straight or one- or two-dimensionally curved / curved material web / profile, use thereof and a device for producing the same |
| DE102011109123B3 (en) * | 2011-08-02 | 2012-08-02 | Dr. Mirtsch Gmbh | Method for producing sound absorbing component for door used in building, involves moving concave curved shell regions against supporting element tool so as to create pressure membrane stresses in shell |
| DE102011111845A1 (en) | 2011-08-27 | 2013-02-28 | Bernd Späth | Hand-guided or hand-operated tool i.e. snow shovel, for use in snow cleaning device, has tool handle, and base or primary structure comprising structural elements with different sizes, where structural elements are formed from projections |
| DE102013017644B4 (en) * | 2012-10-25 | 2017-09-21 | Dr. Mirtsch Gmbh | Method for producing a multi-dimensionally structured material web and use thereof |
| DE102013002213B4 (en) | 2013-02-07 | 2016-06-02 | Dr. Mirtsch Gmbh | Method for producing a structured material web from knitted, knitted or woven threads and use of the same |
| DE102013101749A1 (en) * | 2013-02-21 | 2014-08-21 | Heraeus Materials Technology Gmbh & Co. Kg | catalyst |
| DE102013003094A1 (en) | 2013-02-25 | 2014-08-28 | Bernd Späth | Handheld snow removal tool e.g. snow shovel has shovel blade that is comprised of hexagonal primary patterning structure and provided with reinforcing ribs, where material thickness of blade and ribs are different from each other |
| DE102014000083B4 (en) * | 2014-01-02 | 2017-12-07 | Dr. Mirtsch Gmbh | Method for producing a partially three-dimensional vault-shaped structured material web, partially three-dimensional vault-shaped structured material web, use of the same and a device for producing the same |
| DE102014006096B4 (en) | 2014-04-29 | 2018-01-25 | Dr. Mirtsch Gmbh | Method for producing a multi-dimensionally structured material web for thin-walled planar wall elements and use thereof |
| CN104138956A (en) * | 2014-07-02 | 2014-11-12 | 陈俊达 | Manufacturing method and manufacturing equipment of color steel tile |
| CN105195586A (en) * | 2015-08-21 | 2015-12-30 | 长春理工大学 | Diamond coining forming-based front and back double-surface micro-nano structure, and preparation method of array thereof |
| CN106862352B (en) * | 2017-02-22 | 2020-07-28 | 廖小春 | Rotating structure for stamping license plate, stamping equipment and stamping process thereof |
-
1996
- 1996-04-18 PL PL96329310A patent/PL181398B1/en unknown
- 1996-04-18 CZ CZ983334A patent/CZ333498A3/en unknown
- 1996-04-18 CA CA002248291A patent/CA2248291C/en not_active Expired - Lifetime
- 1996-04-18 EP EP96914934A patent/EP0900131B1/en not_active Expired - Lifetime
- 1996-04-18 HU HU9900710A patent/HUP9900710A3/en unknown
- 1996-04-18 CN CN96180259A patent/CN1076229C/en not_active Expired - Fee Related
Also Published As
| Publication number | Publication date |
|---|---|
| HUP9900710A2 (en) | 1999-06-28 |
| CA2248291A1 (en) | 1997-10-30 |
| EP0900131A1 (en) | 1999-03-10 |
| CZ333498A3 (en) | 1999-08-11 |
| CN1076229C (en) | 2001-12-19 |
| PL329310A1 (en) | 1999-03-15 |
| CN1224374A (en) | 1999-07-28 |
| EP0900131B1 (en) | 2002-10-09 |
| HUP9900710A3 (en) | 2001-01-29 |
| PL181398B1 (en) | 2001-07-31 |
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