DE102018002943A1 - Method and device for producing predetermined breaking points for cover elements of body components - Google Patents

Abstract

The invention relates to a method for producing predetermined breaking points (S) for lid elements (16) of body components (12) for motor vehicles, in which the respective predetermined breaking point (S) by means of an embossing element (14) of a tool (10) in the respective Cartridge component (12) embossed and thereby produced, wherein the tool (10) has a around the embossing element (14) extending around the recess (20) into which the respective body component (12) immersed in the embossing when its wall thickness exceeds a threshold, wherein the recess (20) remains free when impressed when the wall thickness falls below the threshold value.

Description

The invention relates to a method for producing predetermined breaking points for designed as a tear cover cover elements of body parts for motor vehicles according to the preamble of claim 1. Furthermore, the invention relates to an apparatus for performing such a method.

Such a method for producing predetermined breaking points for designed as Aufreißdeckel cover elements of body parts for motor vehicles are already in the DE 10 2016 006 954 A1 known. In the method, the respective predetermined breaking point is embossed by means of an embossing element of a tool in the respective body component and thereby manufactured.

Object of the present invention is to develop a method and an apparatus of the type mentioned in such a way that the predetermined breaking points and thus formed as Aufreißdeckel cover elements can be produced reliably.

This object is achieved by a method having the features of patent claim 1 and by a device having the features of patent claim 5. Advantageous embodiments with expedient developments of the invention are specified in the remaining claims.

In order to develop a method specified in the preamble of claim 1 type such that the predetermined breaking points and thus designed as Aufreißdeckel cover elements in particular can be made particularly reliable process if the body components vary in their wall thicknesses, it is provided according to the invention that the tool has around the embossing element around extending cutout, in which the respective body component dips when impressing the respective predetermined breaking point when the wall thickness of the respective body component exceeds a threshold value also referred to as the setpoint. However, the cutout will remain free when imprinted if the wall thickness exceeds the threshold. In other words, if the wall thickness of the respective body component falls below the threshold value, the body component does not submerge in the recess when the embossing element or the predetermined breaking point is impressed. In this way, below the predetermined breaking point, a sufficient residual wall thickness, also referred to as the residual material thickness, can be realized independently of the original wall thickness, with which the respective body component is supplied, for example, to the tool and, in particular, arranged in the tool.

The inventive method thus makes it possible to produce the respective cover element, for example, based on a can lid, in particular by using a press shop technology, in the context of which the tool has a die and a punch. In this case, the embossing element is provided for example on the die. To impress the embossing element and thus the predetermined breaking point in the respective body component, the die and the punch are moved in translation towards each other, whereby the tool is closed. The tool is a depth-limited tool, since, for example, the embossing element is kept at a distance from the punch by means of at least one spacer element, also referred to as the main distance, when the tool is closed. As a result, the residual material thickness can be ensured as a residual material under the example designed as a notch breaking point. The aforementioned target value (threshold value) is defined, for example, by the distance between the embossing element and the stamp and thus by a distance between the die and the stamp, this distance between the die and the stamp being defined by the aforementioned main distance. The cutout is provided on a passive active surface of the punch or the die and also allows for wall thickness variations of the body components to ensure an at least substantially constant residual material thickness below the predetermined breaking point. This means that the residual material thickness can be maintained at least substantially constant both when the wall thickness exceeds the threshold value and when the wall thickness is below the threshold value. In particular, it is possible by means of the main distance to set the residual material thickness, which is also referred to as residual material thickness, under the predetermined breaking point, in particular as a notch, and thus to bring it to a thickness value to be set in the tool.

The method according to the invention thus makes it possible to control any wall thickness tolerances of the body components designed in particular as body panels in the production of the tear-open lid, wherein the wall thickness tolerances are, for example, 0.8 millimeter +/- 0.04 millimeter. In order to realize a sufficient Ausreißfunktionalität, in which the cover element can be in a particularly simple manner from the rest of the body component or torn, it is desirable to set the residual material thickness to a low value. However, in order to avoid unwanted loosening of the tear-open lid from the rest of the body component, the residual material thickness should not be too low. In particular, it is desirable that the residual material thickness in the body components, despite their possible wall thickness variation, at least substantially to produce constant and at least substantially constant to set to a value of 0.2 millimeters, for example, always solve the respective Aufreißdeckel with the same force from the respective other body component and in particular to be able to tear off. Preferably, therefore, the residual material thickness, which is, for example, a wall thickness at a bottom of the predetermined breaking point, is at least substantially 0.2 millimeters.

The invention is based for example on a forming technique for the production of predetermined breaking points in sheets, which are used for the production of food cans, which can be torn. The food cans are usually made from sheet metal having a thickness of 0.2 millimeters, in particular by forming in a rotary process, whereby the food cans can be produced in an at least substantially continuous process. This tear notches are produced by these are impressed by means of rollers. A rest material thickness arranged under the respective tear notch or adjoining the respective tear notch is typically 0.05 millimeter in order to simply tear open the respective food can by hand. According to the invention, it is now intended to transfer such, rupturable food cans to the body shop or the bodywork of motor vehicles, in particular of passenger cars. For example, depending on the equipment or equipment variant of the respective motor vehicle designed as Aufreißdeckel cover element along the example circumferential breaking point from the rest of the body component torn and thereby torn open, whereby, for example, designed as a passage opening opening of the designed in particular as a body panel body part is released or opened. In this opening, for example, at least one attachment or equipment part can then be arranged so that different equipment variants and thus construction variants of the motor vehicle can be displayed in a particularly simple and cost-effective manner.

How sufficient in the DE 10 2016 006 954 A1 , whose contents are to be considered in its entirety as part of this disclosure, is the predetermined breaking point, for example, a circumferential edge of the cover element formed as a material taper around which the edge circumscribes, for example, in full circumference. The aforementioned opening of the bodywork component is a receiving opening which can be produced in the bodywork component and which can be produced or manufactured in the bodywork component such that the cover element is torn off or torn open along the predetermined breaking point by the rest of the bodywork component. The receiving opening can then be used for receiving at least one optional equipment component of the motor vehicle, wherein the equipment component or fitting part can be of the equipment component.

The invention also includes a device, in particular a tool, wherein the device or the tool is designed for carrying out a method according to the invention. Advantages and advantageous embodiments of the method according to the invention are to be regarded as advantages and advantageous embodiments of the device according to the invention and vice versa.

During the embossing and / or before the embossing and / or after the embossing, for example, the respective body component is reshaped by means of the tool, in particular in the region of the cover element. In other words, for example, the respective body component is subjected to a forming process, which is carried out by means of the tool, by means of which also the predetermined breaking point is produced. In particular, a recess is produced by the forming around which, for example, the predetermined breaking point formed as a notch, in particular completely, rotates.

Due to wall thickness tolerances, in particular sheet thickness tolerances, the tear-open lid is either not operationally stable or the bottom also designated under the notch residual material thickness is so thick that a tear or tearing of the respective tear-off lid is not without damage to the body component or not possible.

The inventive method now makes it possible to produce the respective body component with the respective tear-open reliable and functional. Here, in particular after manufacture, in particular molding, the recess in the bodywork component at a distance from a forming zone in which, for example, the body component is deformed, the predetermined breaking point impressed as a circumferential notch in the body component, wherein material to large sheet thickness or wall thickness in the Cut-out referred to as tool recess, which extends around the embossing element or around an embossing surface for producing the predetermined breaking point, immersed. This ensures that regardless of sheet thickness tolerances or wall thickness tolerances in an additional tolerance range always the same, also referred to as bottom thickness residual material thickness is achieved below the notch. The depth of the predetermined breaking point can change with the wall thickness, in particular in the form that the depth of the predetermined breaking point, which is also referred to as the notch depth, is less for small wall or sheet thicknesses than for wall or sheet thicknesses which are larger in comparison.

Particularly preferably, the predetermined breaking point formed, for example, in a notch region is spaced apart by at least two millimeters from the trough, which is arranged, for example, in the trough region, so that the notch region is spaced at least two millimeters from the trough region. This ensures that in the body component in a transition region of the trough to the notch tensile stresses that are caused by the production of the trough or were compensated with compressive stresses due to the production of the notch. As a result, a wedge hardening only occurs in the region of the notch, so that the tear-open lid does not break away undesirably when the operating load changes.

Particularly preferably, the embossing of the notch in the same tool or by means of the same tool as the production of the trough and in the same or in the same stroke of the tool takes place. Particularly preferably, the distance of the embossing surface or of the embossing element is set to the surface of the body component by spacer elements, in particular in the form of shims.

Further advantages, features and details of the invention will become apparent from the following description of a preferred embodiment and from the drawing. The features and feature combinations mentioned above in the description as well as the features and feature combinations mentioned below in the description of the figures and / or in the figures alone can be used not only in the respectively specified combination but also in other combinations or in isolation, without the scope of To leave invention.

• 1 ausschnittsweise eine schematische Seitenansicht einer zum Durchführen eines erfindungsgemäßen Verfahrens ausgebildeten Vorrichtung zum Herstellen von Sollbruchstellen für als Aufreißdeckel ausgebildete Deckelelemente von Karosseriebauteilen für Kraftwagen;
• 2 ausschnittsweise eine weitere schematische Seitenansicht der Vorrichtung;
• 3 ausschnittsweise eine weitere schematische Seitenansicht der Vorrichtung; und
• 4 ausschnittsweise eine schematische und geschnittene Seitenansicht eines der Karosseriebauteile bei dessen Bearbeitung, die mittels der Vorrichtung durchgeführt wird.

The drawing shows in:

• 1 a schematic side view of a trained for performing a method according to the invention device for producing predetermined breaking points designed as Aufreißdeckel cover elements of body parts for motor vehicles;
• 2 a detail of another schematic side view of the device;
• 3 a detail of another schematic side view of the device; and
• 4 a schematic and sectional side view of one of the body parts in its processing, which is carried out by means of the device.

In the figures, the same or functionally identical elements are provided with the same reference numerals.

1 shows a detail in a schematic side view of a device in the form of a tool 10 for the production of predetermined breaking points for designed as a tear cover lid elements of body parts for motor vehicles, especially for passenger cars. Thus, the tool 10 designed to carry out a method for producing the predetermined breaking points. In 1 is a partial with a 12 designated the body components recognizable, the previous and following statements to the body component 12 can be easily transferred to the other body parts and vice versa. The respective body component is formed for example from a metal sheet and thus formed as a body panel.

In the method, the respective predetermined breaking point by means of an embossing element 14 of the tool 10 imprinted in the respective body component and thereby produced. The predetermined breaking point of the body component 12 is in 2 and 3 recognizable and designated there by S. To do that in 2 and 3 With 16 designated and designed as Aufreißdeckel cover element is not completely from the rest of the body component 12 to separate, penetrates the embossing element 14 when impressing the body component 12 not completely, but under the example designed as a notch and, for example, the cover element 16 completely circumferential predetermined breaking point S remains a referred to as residual material thickness residual material thickness 18 , In this case, it is desirable to produce the residual material thicknesses of the body components at least substantially constant despite any wall thickness tolerances of the body components, and to set them to, for example, 0.2 millimeters. In order to realize this, and thus to be able to produce the cover elements particularly reliably, the tool has 10 one around the embossing element 14 extending around and also referred to as a tool recess recess 20 on, in which when impressing and thus producing the respective predetermined breaking point, the respective body component dips when its wall thickness exceeds a threshold value, also referred to as setpoint, that is, when the wall thickness is greater or thicker than the desired value. However, if the respective wall thickness of the respective body component falls below the nominal value, so that the respective body component or its wall thickness is smaller or thinner than the nominal value, then the body component does not dip into the body Saving one. In other words, then the cut-out remains 20 free when memorizing.

Out 1 to 3 is particularly well recognizable that the tool 10 a die 22 has, on which the embossing element 14 is provided. In particular, the embossing element 14 under the mediation of a tuning plate 24 at the die 22 held by varying the tuning plate 24 a distance of the embossing element 14 to the matrix 22 can be adjusted. Furthermore, the tool includes 10 one of the die 22 opposite stamp 26 , The matrix 22 with the embossing element 14 and the stamp 26 are tool parts of the tool 10 , wherein the tool parts can be moved relative to each other in translation. The tool parts can thus be moved towards each other, whereby the tool 10 is closed. Furthermore, the tool parts can be moved away from each other, whereby the tool 10 is opened. Is that tool 10 opened, so is the body part 12 in the tool 10 introduced and thereby arranged at least partially between the tool parts. In between the tool parts arranged state of the body component 12 the tool parts are moved towards each other, causing the tool 10 is closed. In the course of closing the tool 10 leads the tool 10 or perform the tool parts a hub, in whose frame the embossing element 14 in the bodywork component 12 imprinted and thus the predetermined breaking point S is produced. In addition, in the course of the same hub, the body component 12 at least in a forming area U reshaped, with the body component 12 for example, is shaped like a pot. Here, for example, the body component 12 at least in the forming area U between the die 22 and a holder designed, for example, as a hold-down device or as a sprung spring base 28 held between the matrix 22 and the holder 28 clamped. The holder 28 is also referred to as a sheet holder, since the body component 12 for example, is designed as a body panel or from a sheet or as a metal sheet. In particular, the body component 12 formed by the forming pot-shaped, whereby on the respective body component 12 a circumferential, out 4 recognizable S-beat 30 will be produced. As a result, for example, on the body component 12 a potty 32 made, which can also be referred to as a trough.

A first partial step of the forming is, for example, the production or molding of the potty 32 with the S-beat formed for example by a circumferential S-beat surface 30 , Here are in the bodywork component 12 , In particular, in its material, introduced tensile stresses, which counteract the compressive stresses caused by the production of the designated breaking point S as a notch, counter. Basically, this opens up the possibility of reshaping locally, that is, independent of the wider environment outside the potty 32 , consider.

In the context of a further processing or forming step of the notching, which is also referred to as embossing, the above-mentioned compressive stresses are introduced locally. In other words, for example, after the preparation of the potty 32 the embossing element 14 in the bodywork component 12 impressed or embossed, whereby the compressive stresses locally in the body component 12 be introduced. By the previously introduced tensile stresses compressive stresses are compensated outside the notch in an edge region. Under the notch high compressive stresses are introduced. This leads to a local work hardening. The stress distribution around the notch and the work hardening help that the easy to open lid also called lid does not break when operating load cases. The embossing of the notch, also referred to as a notch structure, around the S-striking surface, which is produced, for example, in the context of a post-forming operation, is in the same tool stage of the tool 10 integrated or follow, for example, in the same hub of the tool 10 , Basically, the stamp presses 26 for example, designed as a sheet metal body component 12 against the embossing element designed as a notching tool 14 in the mold 22 , The area of the bodywork component to be embossed 12 must not be so far consolidated by preceding transformations that cracks occur when embossing the notch. As a design rule has proven to be advantageous if the notch is spaced at least two millimeters from the deformed or deformed area to prevent tearing of the sheet. Advantageous is a relative deformation in the residual material thickness 18 75 percent or 10 percent strain hardening in the notch bottom to cause breakage during the tearing operation.

In 4 B denotes an area in which the aforementioned stresses cancel each other out. Here are in 4 by arrows forces in the body component 12 , or in its material, illustrated. Furthermore, in 4 C denotes a region in which material, in particular by the production of the predetermined breaking point S, compacted.

• - Adaption der Verpackungstechnologie im Karosseriebau
• - kostengünstige Möglichkeit, den Rohbau zu flexibilisieren
• - höherer Anteil geschlossener Strukturen in der Karosserie
• - Reduzierung der Beschallung

In particular, the following advantages can be realized by the method described and by the device designed to carry out the method:

• - Adaptation of packaging technology in body construction
• - cost-effective way to make the carcass more flexible
• - higher proportion of closed structures in the body
• - Reduction of the sound

The tool 10 is a depth-limited tool because in the closed state of the tool 10 a distance between the die 22 and the stamp 26 , In particular, a distance between the embossing element 14 and the stamp 26 , and thus the residual material thickness 18 using one as the main distance 34 designated spacer element is defined. In other words, the tool parts from each other and thus the embossing element 14 from the stamp 26 by means of the main distance 34 spaced from each other or held in the aforementioned distance from each other.

According to 2 falls below the wall thickness of the body component 12 the setpoint. This leaves the cut-out 20 free when memorizing. According to 3 however, the wall thickness is greater than the set point, so the body panel 12 when impressing in the cutout 20 dips. As a result, despite the wall thickness tolerance, the residual material thickness of the respective body components can be kept at least substantially constant.

QUOTES INCLUDE IN THE DESCRIPTION

This list of the documents listed by the applicant has been 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.

Cited patent literature

• DE 102016006954 A1 [0002, 0009]

Claims (5)

Method for producing predetermined breaking points (S) for cover elements (16) of body components (12) for motor vehicles in the form of tear-open covers, in which the respective predetermined breaking point (S) is inserted into the respective body component (12) by means of an embossing element (14) of a tool (10) stamped and thereby produced, characterized in that the tool (10) has a recess (20) running around the embossing element (14) into which the respective body component (12) dips when impressed when its wall thickness exceeds a threshold value, wherein the Clearance (20) remains free when impressed when the wall thickness is below the threshold value. Method according to Claim 1 , characterized in that the respective body component (12) during the embossing and / or before the embossing and / or after the embossing by means of the tool (10) in the region of the cover element (16) is formed. Method according to Claim 2 , characterized in that the respective body component (12) is reshaped by the forming pot-shaped, whereby on the respective body component (12) a circumferential S-beat (30) is formed. Method according to one of the preceding claims, characterized in that the respective body component (12) is held during impressing by means of a hold-down device (28) or a sprung spring plate (28). Device (10) for carrying out a method according to one of the preceding claims.

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