DE102022103395A1 - Method for producing a perforated sheet, perforated sheet, use of a pressed-in additional material and use of a perforated sheet - Google Patents

Abstract

Method for producing a perforated sheet (12), at least comprising the following steps: a) providing a sheet (1); b) defining a hole area (2); c) introducing a predetermined hole (3) in the entire hole area (2); d) Closing the perforation (3) in at least one zone (4) of the perforated area (2) by filling the perforation (3) with an additional material (5), the additional material (5) being arranged only in the perforated area (2). Correspondingly produced perforated plates (12) and their advantageous uses are specified.

Description

The present invention relates to a method for producing a perforated sheet, a perforated sheet, the use of a pressed-in additional material in a perforated sheet and the use of a perforated sheet itself.

The invention relates in particular to the production of perforated metal sheets of the type of ventilation sheets, screens, ceiling panels, soundproofing elements and the like.

Usually, large-area perforated sheets are made of metal, with the holes being made in particular by punching in a sheet of steel, aluminum or the like. Perforated plates of this type can be produced with a variable shape of holes and/or with predefined perforated fields, edges and/or webs.

In view of the different possible uses of such perforated plates, it has been found that it is desirable not to provide a hole pattern in small, local areas and/or at edge areas of the perforated plates, but instead to provide a completely closed section of the plate. However, this turns out to be difficult or complex in production, in particular when using large punches that are limited in terms of their hole pattern.

If, for example, (unperforated) bordered fastening holes are to be provided for the perforated plate, their size and position may vary considerably, so that their position cannot be defined or taken into account in the manufacturing process. In this case, a washer may have to be positioned and fastened to the perforated plate by hand using clips, possibly in connection with post-processing of the design of the (larger) fastening through-hole.

It must also be taken into account that the (time-consuming) control of stamps in the punching system in order to specifically omit sheet metal areas in the perforation process can lead to considerable stresses in the perforated sheet. As a result, it cannot be ensured during the (subsequent) forming process that the position/shape of the unperforated sheet metal area is maintained. As a result, this is sometimes accompanied by unacceptable tolerances.

The introduction of unperforated areas is limited in terms of size, shape and position due to the tool or only possible with very complex punching machines or punching tools. This results in considerable costs.

Unperforated local areas in a perforated sheet can be provided for power transmission and be provided with additional elements such. B. Washers or plates that are welded on. However, this requires mostly manual rework, which may be time-consuming and not very precise.

Proceeding from this, it is the object of the present invention to at least partially solve the problems described with reference to the prior art. In particular, solutions are to be specified as to how local and limited, non-perforated areas can be produced in such a perforated sheet, for example to reinforce edges, to produce connecting sections and/or to implement design elements.

These objects are achieved with a method according to the steps of claim 1, a perforated plate with the features of claim 10 and/or the uses according to claim 12 or claim 13. Further advantageous configurations of the invention are specified in the dependent claims. It should be pointed out that the steps and features listed in the claims can be combined with one another in any technically appropriate manner and show further refinements of the invention. The description, in particular in connection with the figures, explains the invention and specifies further preferred exemplary embodiments.

1. a) Bereitstellen eines Bleches;
2. b) Festlegen eines Lochbereichs;
3. c) Einbringen einer vorgegebenen Lochung in den gesamten Lochbereich;
4. d) Verschließen der Lochung in mindestens einer Zone des Lochbereichs durch Auffüllen der Lochung mit einem Zusatzmaterial, wobei das Zusatzmaterial nur im Lochbereich angeordnet wird.

A method for producing a perforated sheet contributes to this, which comprises at least the following steps:

1. a) providing a metal sheet;
2. b) defining a hole area;
3. c) introducing a predetermined hole in the entire hole area;
4. d) Closing the perforation in at least one zone of the perforation area by filling the perforation with an additional material, the additional material being arranged only in the perforation area.

Steps a) to d) can be carried out at least once in the order given here. However, it is also possible for the steps to be carried out at least partially in parallel or simultaneously.

A metal sheet can be provided in particular in such a way that the metal sheet is provided in a large format and/or pulled from the coil. The metal sheet is in particular a (flat, smooth or even) Sheet metal, which has a sheet thickness in the range of 0.4 to 5.0 mm, for example. It is further preferred that the metal sheet is provided over its entire surface, closed and with a single material.

With regard to the sheet metal provided, a hole area must be defined in accordance with step b). In principle, it is also possible that a plurality of hole areas, possibly adjacent or spaced apart from one another, are defined with respect to a metal sheet to be machined. The hole area is characterized in particular by the fact that it is to be provided with a predefined hole or with a hole pattern. The hole area is defined in particular for the punching processing of the sheet metal and can in this respect be predefined by the effective area of a corresponding hole punch.

A predetermined perforation or a predetermined hole pattern is actually made in this selected or specified hole area. As a result, after the predetermined perforation has been made, the entire hole area can only consist of narrow webs that space the holes from one another. The entire hole area is then preferably only formed with webs which have a maximum web width of 1.0 mm or even a maximum of only 0.7 mm [millimeters]. It is fundamentally possible that there are different hole patterns or different sizes and/or shapes of holes in the hole area. The perforation in the hole area is preferably made with a maximum size of 8 - 8.7 or even a maximum of 6 - 6.7 (where the first value is the hole width or the hole diameter in millimeters and the second value is the pitch or the distance between the centers of adjacent holes in millimeters, cf. DIN 24041 if applicable).

It is particularly preferred that the perforated sheet (at least after the perforation has been made) is still essentially flat, smooth and/or level, i.e. for example no raised perforated edges, collars, etc. in the perforated area (whereby smaller, possibly unstable and /or only burrs facing towards one surface - e.g. with a burr overhang of a maximum of 0.2 mm [millimeters] - resulting from a stamping process, for example, are of course permissible). It is very particularly preferred that the holes in the perforation do not have any (separately) reinforced hole edges.

It is possible that the perforated sheet has internal stresses due to being wound on a coil and/or due to the perforation being made, which may have a wavy and/or (partially) rolled shape. It is possible in such cases to subject the plate to an additional straightening pass to (significantly) improve the flatness of the perforated plate - but this is not necessary.

The sheet thickness of the perforated sheet will be essentially unchanged before and after the perforation, e.g. B. with the exception of a punching burr.

The perforation is made in particular by means of a punching process. The punching process is preferably carried out using a wide or strip press. This punches the sheet metal across the entire width in a single operation, with one or more rows of punches one behind the other perforating the sheet metal at a high stroke rate. Hole shape, size and spacing can vary.

After such a perforation has been made, according to step d), the perforation is closed again in at least one zone of the perforated area, specifically by filling the perforation with an additional material. In principle, it is possible for several zones in the entire perforated area to be closed again by filling in additional material. This can be done simultaneously or at different times. "Filling up" the perforation means here in particular that the additional material is actually introduced into the perforation and in particular does not just cover or cover it. It is very particularly preferred that the perforation in the at least one zone is filled at a specific point in time or at the same time. In other words, this means in particular that several, in particular adjacent, holes of the perforation are provided with additional material at the same time or this is introduced there at the same time. It is possible for the additional material to be cut in such a way that it can be introduced in one piece into the perforation in the at least one zone. It is thus realized in particular that the entire perforation in the at least one zone is closed with a single process and not each hole individually one after the other. The introduction of the additional material can take place over (on average) at least 50% of the sheet thickness, in particular over (on average) at least 80% of the sheet thickness. It is preferred that the additional material is substantially flush with the sheet metal thickness on one side or optionally on both sides, and does not protrude beyond it or does not protrude beyond it.

It is also noteworthy that the additional material is only arranged in the perforated area, so that in particular no (sideways or lateral) overlap is realized beyond the perforated plate or beyond the perforated area. This means in particular that by step d) no lap joint to connect multiple sheets or to increase the Dimensions of the perforated plate is sought or realized.

• - genaue Positionierung der Zonen bzw. verschlossenen Lochblechbereiche, z. B. für Befestigungslöcher
• - individuelle Form der Zonen einstellbar
• - reduzierte Prozesszeiten
• - Reduzierung bzw. Vermeidung von Spannungen im Lochblech
• - Erzeugen kleiner, lokaler Verstärkungszonen
• - Kantenschutz

The method proposed here offers a simple, visually appealing solution that can be implemented quickly, even in the case of perforated sheets that are only finely perforated and/or perforated sheets that are difficult to weld or can be subjected to high loads. The advantages are in particular:

• - Exact positioning of the zones or closed perforated plate areas, e.g. B. for mounting holes
• - Individual shape of the zones adjustable
• - reduced process times
• - Reduction or avoidance of stresses in the perforated sheet
• - Creation of small, local reinforcement zones
• - Edge protection

• - verstärkte Flächen für Niet- und/oder Schraubverbindungen,
• - Fläche für Warenaufkleber,
• - Fläche für Herstellerlogos,
• - Kantenschutz,
• - Verbesserung der Arbeitssicherheit, keine Verletzungsgefahren durch „Fischhaken“.

This process makes it possible to create functional surfaces in the visible and/or non-visible area of the perforated sheet, which can have the following functions:

• - reinforced surfaces for rivet and/or screw connections,
• - area for goods stickers,
• - area for manufacturer logos,
• - Edge protection,
• - Improvement in occupational safety, no risk of injury from "fish hooks".

The method can be designed in such a way that the at least one zone does not exceed 20% of the hole area. For example, the at least one zone can make up a proportion of 3% to 20%, for example also 5% to 10%, of the entire hole area. It is therefore clear that the method is used in particular where it is uneconomical to convert the large-area hole punching machine or where variations in the hole pattern can only be provided with great effort and expense.

The additional material is preferably pressed into the metal sheet in step d). For this purpose, provision can be made, for example, for the additional material to be placed adjacent (above and/or below) the at least one zone and then pressed into the existing perforation. In this step d), in particular, the material of the additional material is pressed into the holes or perforations of the perforated plate, so that a form fit and/or a material connection caused by the pressing is realized, so that a firm connection between the perforated plate and the additional material is realized.

With regard to the material, it is preferable for the metal sheet to be formed from steel, while the additional material includes, for example, aluminum or an aluminum alloy. The additional material can be designed as a rolled plate, for example. In particular, a perforated steel sheet is formed in this way, which finally has an unperforated zone with additional aluminum material. The perforated steel sheet can therefore be connected to unperforated aluminum to create an unperforated area in the fully perforated hole area.

The steel sheet can be, for example, a cold-rolled, possibly oiled, thin sheet. An unalloyed quality steel or structural steel can be used, e.g. B. a DC01 (1.0330), cf. EN 10130 .

With regard to the additional material, non-hardenable, formed aluminum materials are preferred. Such materials are not thermally critical and can be permanently exposed to temperatures of up to approx. 120° C, briefly (approx. 4 - 6 h) also up to approx. 180° C. Wrought aluminum alloys with at least 99% aluminum and a strength of 70 are preferred up to 190 in N/mm ² ; or with 0.2 to 6.2% Mg and a strength of 100 to 450 in N/mm ² .

It is possible to use an aluminium-magnesium alloy as additional material, in particular re-annealed and work-hardened.

An aluminum-magnesium alloy with a material thickness of 1.5 to 2.0 mm is particularly preferred as additional material.

It is preferred to provide a metal sheet with a maximum sheet metal thickness of 2.0 mm in step a). It is particularly preferred that the sheet metal thickness does not significantly exceed this sheet metal thickness even in the region of the at least one zone after the perforation has been filled with an additional material. It is very particularly preferred that the sheet metal thickness is a maximum of 3.0 mm in the area with the closed perforation.

It is preferred that the (plate-like) additional material is provided with a material thickness (precisely for the pressing-in process) which corresponds at least to the sheet thickness of the perforated sheet. It is possible that the material thickness is not more than twice the sheet metal thickness.

Tests with the perforated plates presented here have shown that a thicker version of the (aluminium) additional ma materials leads to a better or more resilient connection of the joining partners. It was also determined that the shearing test depends on whether the connection is unbuttoned. If this is the case, the maximum shearing force is higher because the perforated sheet is deformed further after it has been untied (usually in the edge area). No detachment means a rigid connection and thus a lower shearing force.

According to a further embodiment, it is proposed that in step c) a perforation with an openness of at least 40% be introduced. In other words, this means in particular that the proportion of holes in relation to the total area of the hole area is at least 40%, particularly preferably at least 60% or even at least 80%. It is possible that the openness in the area of the hole area varies, possibly also by removing or not executing webs of a uniform pattern of the hole.

The at least one zone can be created at a distance from an edge of the metal sheet or from an edge of the hole area. In other words, this means that the at least one zone is formed in an inner area of the hole area. The edge of the sheet forms the end of the surface of the sheet and the edge of the hole area forms the boundary of the defined hole area within or on the sheet. It is possible for the edge of the sheet metal and the edge of the hole area to coincide, but this is not essential.

The at least one zone can have, at least in sections, a different perforation than outside of the at least one zone. In particular, it is possible for the openness to be greater in at least one section of one zone than outside or adjacent to the zone due to another perforation. This can again be realized by omitting or removing webs in a uniform hole pattern.

According to a further embodiment variant, it is possible for the perforated plate to be bent in step e). This means in particular that the combination of additional material and perforated sheet metal is then subjected to a forming process, in particular a bending process, so that a three-dimensional contour is produced from the essentially two-dimensional, flat perforated sheet metal. It is possible for this step e) to at least partially include step d).

According to a further embodiment variant, it is proposed that the perforated metal sheet be coated in a step f). Step f) includes in particular a so-called KTL coating. KTL coating is an electrochemical process in which the perforated sheet is coated with electrically conductive, water-based dip paint in a dip bath. It is also possible at the end to burn in the coated perforated sheet in a continuous furnace at a temperature between 150°C and 230°C. In this way it is possible to form a solvent- and corrosion-resistant, impact-resistant and/or scratch-resistant surface that is resistant to acids and alkalis.

It is possible to provide the surfaces of the perforated sheets with a powder coating, which also ensures additional protection against (contact) corrosion, UV radiation, scratches and stone chips. It is preferred that step f) includes the implementation of both a KTL and a powder coating.

According to a further aspect, a perforated plate is proposed which has a hole area in which a hole has been made over the entire surface and in at least one zone of the hole area the hole is closed with an additional material. The perforated sheet was produced in particular using a method proposed here.

The configurations of the perforated sheet (dimensions, materials, openness, sheet thickness, etc.) specified in connection with the proposed production method can also be used here to characterize the perforated sheet, independently of the actual production of the perforated sheet.

It is particularly preferred that the perforation forms a surface of the perforated plate at least on one side in the area of the at least one zone. In other words, this means in particular that the perforation or the perforated plate can still (slightly) be recognized or felt in the at least one zone. This can be realized in particular in that the additional material in the at least one zone does not fill out the perforation over the entire sheet thickness, at least or only on one side, but only partially over its sheet thickness. In other words, it is possible that the additional material does not end flush with the surface of the perforation or the webs of the perforated plate, but rather a (recessed or raised) surface structure is formed.

According to a further aspect, the use of a pressed-in additional material in at least one zone of a perforated plate to enlarge contact surfaces of the perforated plate is also proposed. This means in particular that the top and/or bottom of the perforated plate has an enlarged contact surface, for example for connectors training means and/or the application of logos and the like.

According to yet another aspect, the use of a perforated metal sheet, which was produced using a method proposed here, is proposed as a ventilation grille for a vehicle or a machine. A ventilation grille is used in particular for the passage of air for cooling and/or the supply of combustion air in a vehicle and/or a work machine.

• 1: einen Ausschnitt eines Blechs,
• 2: einen Ausschnitt aus einem Lochblech vor dem Zusatz von Zusatzmaterial,
• 3: das Lochblech aus 2 nach Hinzufügen des Zusatzmaterials,
• 4: eine Schnittansicht durch ein Lochblech nach dem Zuführen des Zusatzmaterials,
• 5: eine Draufsicht auf ein Lochblech im Bereich der mindestens einen Zone mit Zusatzmaterial,
• 6: eine perspektivische Darstellung eines Abschnittes eines Lochblechs mit mehreren Zonen mit Zusatzmaterial, und
• 7: Veranschaulichung des Fügeprozesses des Zusatzmaterials hin zum Lochblech.

The invention and the technical environment are explained in more detail below with reference to various figures. It should be pointed out that the same parts in the individual figures are usually provided with the same reference numbers. It is possible to combine details from one figure with details from another figure and/or features of the general description, unless explicitly excluded here. The figures are schematic in nature and show the following:

• 1 : a section of sheet metal,
• 2 : a section of a perforated plate before the addition of additional material,
• 3 : the perforated sheet off 2 after adding the additional material,
• 4 : a sectional view through a perforated plate after the additional material has been fed in,
• 5 : a top view of a perforated plate in the area of the at least one zone with additional material,
• 6 : a perspective representation of a section of a perforated plate with several zones with additional material, and
• 7 : Illustration of the joining process of the additional material to the perforated sheet.

1 shows first the provision of a metal sheet 1 according to step a) of the method presented here. The metal sheet 1 can be characterized by a defined hole area 2, which can make up the entirety of the metal sheet 1, for example. It is also indicated here schematically that the metal sheet 1 forms an outer peripheral edge 8 which, in particular, at least partially defines or limits the dimensions of the metal sheet 1 . It is also explained here that an edge 9 of the hole area 2 can also be formed. In the exemplary embodiment shown here, the hole area 2 is designed in such a way that it extends from the edge 8 to the edge 9 .

2 FIG. 12 now illustrates a perforated sheet metal 12, produced from sheet metal 1, a plurality of holes having a hole width 14 already being formed here according to step c). The perforation 3 in this case comprises a multiplicity of essentially honeycomb-shaped holes which are delimited or defined by the remaining webs of the metal sheet 1 . 2 also illustrates that the openness 7 of the perforation 3 can vary, in particular with respect to a zone 4. The openness 7 is preferably at least 40%.

3 illustrates how the perforated plate 12 is designed after the perforation 3 in the zone 4 has been closed by filling it with an additional material 5. It can be seen that the additional material 5 is only arranged in the hole area 2, ie in particular does not protrude beyond an edge 8 of the metal sheet 1, for example.

4 shows in cross-section and enlarged that the additional material 5 (here from below) was pressed into the metal sheet 1 for the production of the perforated sheet metal or vice versa, the perforated sheet metal was pressed into the additional material 5 . It is also illustrated that the sheet metal 1 is provided with a sheet metal thickness 6 of, for example, a maximum of 2.0 mm and that after the joining of the additional material 5 and sheet metal 1 a material thickness 13 is realized which is, for example, in the range from 1.5 to 3.0 mm lies. It can be seen that the pressed-in additional material 5 serves to enlarge a contact surface 11 of the perforated plate 12 . At the same time it can be seen that the perforation 3 or the remaining webs of the metal sheet 1 form a surface 10 of the perforated metal sheet 12 even in this joined state.

This is further illustrated in 5 , which depicts a plan view of a surface 10 of the perforated plate 12. The perforated plate 12 can be seen, with the additional material 5 being introduced into the perforation 3 .

6 illustrates a perspective view of a further section of a perforated plate 12, produced from a plate 1, wherein first a specific hole area 2 was defined and then in the defined hole area 12 here two zones 4, namely once near the edge 8 of the metal sheet 1 and once at a distance In addition, additional material 5 was introduced, so that part of the perforation 3 is closed. In the area of the edge 8, for example, an enlarged contact surface 11 can be formed, for example in order to fasten or attach the perforated plate 12 to other components, machines and/or vehicles. The area of a circular zone 4 shown at the top right forms, for example, a circular passage 15 that is helpful for establishing a rivet and/or screw connection. The passage 15 can be realized by a further process step, such as by means of a laser.

7 once again illustrates the joining process, with the additional material 5 now being pressed into the metal sheet 1 . up in 7 indicates that the metal sheet 1 or perforated metal sheet 12 is positioned with its multitude of holes, with the additional material 5 being positioned adjacent to the at least one zone 4 . The adjacent or adjacent additional material 5 can be pressed into the perforation 3 of the perforated plate 12 by applying a corresponding force or pressure, so that a permanent connection is created there. It is possible that the additional material 5 now forms a surface 10 and/or a contact surface 11 of the perforated plate 12 .

Possibilities were thus shown here for at least partially solving the problems described with reference to the prior art. In particular, solutions were given as to how local and limited, non-perforated areas can be produced in a perforated sheet, for example to reinforce edges, to create connecting sections and/or to implement design elements.

Reference List

1

sheet

2

hole area

3

perforation

4

Zone

5

additional material

6

sheet thickness

7

openness

8th

edge

9

edge

10

surface

11

contact surface

12

perforated plate

13

material thickness

14

hole width

15

passage

QUOTES INCLUDED IN DESCRIPTION

This list of documents cited by the applicant was generated automatically and is included solely for the better information of the reader. The list is not part of the German patent or utility model application. The DPMA assumes no liability for any errors or omissions.

Non-patent Literature Cited

• DIN EN 10130 [0027]

Claims (13)

Method for producing a perforated sheet (12), at least comprising the following steps: a) providing a metal sheet (1); b) defining a hole area (2); c) making a predetermined hole (3) in the entire hole area (2); d) closing the perforation (3) in at least one zone (4) of the perforated area (2) by filling the perforation (3) with an additional material (5), the additional material (5) being arranged only in the perforated area (2). procedure after claim 1 , in which the at least one zone (4) does not exceed a proportion of 20% of the hole area (2). Method according to one of the preceding claims, in which the additional material (5) is pressed into the metal sheet (1) in step d). Method according to one of the preceding claims, in which in step a) a sheet (1) with a sheet thickness (6) of at most 2.0 mm is provided. Method according to one of the preceding claims, in which in step c) a perforation (3) with an openness (7) of at least 40% is introduced. Method according to one of the preceding claims, in which the at least one zone (4) is produced at a distance from an edge (8) of the metal sheet (1) or from an edge (9) of the hole region (2). Method according to one of the preceding claims, in which the at least one zone (4) has, at least in sections, a different perforation (3) than outside the at least one zone (4). Method according to one of the preceding claims, in which the perforated plate (12) is bent in a step e). Method according to one of the preceding claims, in which the perforated metal sheet (12) is coated in a step f). Perforated plate (12) with a hole area (2) in which a hole (3) has been introduced over the entire surface and in at least one zone (4) of the hole area (2) the hole (3) is closed with an additional material (5). Perforated plate (12) according to the preceding claim, the perforation (3) forming a surface (10) of the perforated plate (12) at least on one side in the region of the at least one zone (4). Use of a pressed-in additional material (5) in at least one zone (4) of a perforated plate (12) to enlarge contact surfaces (11) of the perforated plate (12). Use of a perforated sheet (12) produced by a method according to one of Claims 1 until 9 as a ventilation grille for a vehicle or machine.

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