Method for producing a sealing and edge-protection profile, and extrusion die for forming a sealing or edge-protection profile

Abstract

The invention relates to a method for producing a sealing or edge-protection profile (1) by means of extrusion, and to an extrusion die suitable therefor. In order to create local cross-sectional changes in the sealing or edge-protection profile (1) in a particularly low-maintenance and cost-effective manner, local cross-sectional changes (7; 8) are created in the sealing or edge-protection profile (1), in an extrusion die and / or downstream of a nozzle of an extrusion die in the extrusion direction, by an amorphous medium fed under pressure.

Description

[0001]

[0002] Description:

[0003] CQLT SaarGummi Technologies S.ä.rL, L-5544 Remich (Luxembourg)

[0004] Method for producing a sealing or edge protection profile and

[0005] Extrusion tool for forming a sealing or edge protection profile

[0006] The invention relates to a method for producing a sealing or edge protection profile, in particular a sealing or edge protection profile for a motor vehicle, according to the preamble of claim 1, as well as to an extrusion tool for forming a sealing or edge protection profile. However, the sealing or edge protection profile according to the invention can also be used in all other industries, for example, in the construction sector as a building or window sealing profile.

[0007] Through practice, it is known to introduce local cross-sectional changes into a polymer or elastomer sealing profile after extrusion by mechanically removing still-soft material, for example, using styli fed laterally to the extrusion direction. Depending on the depth and duration of the material removal via the stylus, superficial material thinnings are created to form, for example, predetermined bending points or through-holes as vents and recesses to enable small bending radii of the sealing or edge protection profile. However, this material removal results in material loss, which must be disposed of as waste.

[0008] The object of the invention is to provide a method for producing a sealing or edge protection profile and an extrusion tool suitable for this purpose, which enable a particularly low-maintenance and cost-effective production of local cross-sectional changes.

[0009] This problem is solved by producing the sealing or edge protection profile by extrusion in an extrusion die, whereby local cross-sectional changes are created in the sealing or edge protection profile in or downstream of the extrusion die by a pressurized, amorphous medium. This allows local cross-sectional changes such as predetermined bending points, profile openings, or recesses of any shape and size to be produced without wear. Unlike, for example, with a mechanical stylus, there is no friction with the material of the sealing or edge protection profile when creating the local cross-sectional changes.In addition, the amorphous medium can be guided to virtually any point in the cross-section of the sealing or edge protection profile through appropriate channels in the extrusion die or downstream of the extrusion die, so there are no restrictions regarding the position, number, and variety of predetermined bending points, profile openings, and recesses. Since no material is removed, no waste is generated.

[0010] The amorphous medium can advantageously be a fluid, particularly a liquid or a gas, such as compressed air. Compressed air is particularly inexpensive and can be produced on-site. Alternatively, other gases, particularly (inert) noble gases, or liquids can also be used. Liquids as an amorphous medium have the advantage of being virtually incompressible and therefore particularly well-suited to transmitting dynamic pressure fluctuations to the point where local cross-sectional changes are to be generated.

[0011] To create local cross-sectional changes, the amorphous medium can be pressed against the surface of the (still soft) sealing or edge protection profile in the extrusion die or downstream of the extrusion die, preferably laterally to the extrusion direction, resulting in local material displacement. The amorphous medium can act against the surface of the sealing or edge protection profile via appropriate channels in the extrusion die or downstream of the extrusion die, from the outside or, in the case of cavities in the sealing or edge protection profile, also from the inside, laterally to the extrusion direction, to displace material there.

[0012] The local cross-sectional changes in the sealing or edge protection profile can preferably be material thinning, in particular in the form of predetermined bending points, and / or profile openings, in particular in the form of through holes, and / or recesses. Predetermined bending points are required, for example, when certain kinematic specifications must be met under load. This can, for example, involve targeted deformation in a certain direction. Ventilation openings are introduced where geometric changes in a sealing or edge protection profile with a hollow chamber lead to compression of the air within the hollow chamber. The hollow chamber can be vented via appropriately dimensioned venting openings, which also allows the counterforce against the compression to be adjusted. Recesses are required, for example, where profiles are bent around radii.The areas that lie within the radius of curvature and far away from the neutral fiber tend to be waviness due to material accumulation (compression), which can be prevented by recesses such as punching.

[0013] By specifically controlling the duration and intensity of the possibly intermittent supply of the amorphous medium, for example, the level of air pressure, the cross-section of the sealing or edge protection profile can be locally adjusted through material displacement with a defined depth and position / geometric orientation. This makes it possible to create almost circular recesses with a short pulse. With a longer supply of the amorphous medium, depending on the pressure level, for example, at low pressure, material displacement can be achieved only close to the surface to create a predetermined bend, or at higher pressure, a linear recess or elongated hole can be created.Since the supply of the amorphous medium can be altered during extrusion and can also vary in cross-section at several points, the amorphous medium can be used to create local cross-sectional changes of varying sizes both in the cross-section and in areas with varying frequencies of local cross-sectional changes in the longitudinal direction of the sealing or edge protection profile. In particular, the local cross-sectional changes in the sealing or edge protection profile can be created in such a way that they are spaced apart from one another in the longitudinal direction of the sealing or edge protection profile and / or in the cross-section of the sealing or edge protection profile. This allows the sealing or edge protection profile to be optimally adapted to the planned installation situation, for example, to the existing curvature radii of a door frame.

[0014] In a particularly preferred embodiment, the pressure of the supplied amorphous medium can be varied during extrusion. In particular, it can be provided that no pressure is exerted on the amorphous medium for a time, so that the amorphous medium is supplied intermittently and no local cross-sectional change is provided at the relevant point in the cross-section in corresponding length sections.

[0015] Furthermore, an extrusion tool for forming a sealing or edge protection profile, in particular a sealing or edge protection profile for a motor vehicle, is claimed, comprising a nozzle through which material of the sealing or edge protection profile can be extruded during extrusion. At least one channel for a pressurized, amorphous medium is provided in the nozzle or downstream of the nozzle in the extrusion direction.

[0016] The at least one channel preferably ends on an inner side of the nozzle, i.e. a side which, during extrusion, may rest against and guide the material to be extruded. The amorphous medium is fed through the channel laterally to the extrusion direction and can thus displace the still soft material of the sealing or edge protection profile in the extrusion tool to achieve the desired local cross-sectional changes. In a particularly preferred embodiment, several channels for a formless medium fed under pressure open out on the inside of the nozzle. The mouths / outlet openings of the channels can be spaced apart from one another in the cross-section of the nozzle, whereby the channels can be formed separately and connected to separate pressure sources for individual adjustment and regulation of the pressure.Alternatively, the channels can also be at least partially interconnected to supply multiple channels jointly via a single pressure source. Additive manufacturing processes are preferably used to produce the nozzle, which allows for particularly small and even angled channels. Alternatively or additionally, at least one channel can be provided downstream of the nozzle in the extrusion direction, for example, in a corresponding pipeline. This channel supplies the amorphous medium laterally to the extrusion direction, against the material exiting the nozzle. This also allows a local cross-sectional change to be achieved through material displacement.If several channels are provided behind the nozzle in the extrusion direction, these channels can be arranged as described above, in particular with mouths / outlets spaced apart from one another in cross-section, and can be connected to separate pressure sources or at least partially common pressure sources.

[0017] Further features and advantages of the invention will become apparent from the following description of preferred embodiments with reference to the drawings. They show:

[0018] Fig. 1 is a perspective view of a first embodiment of a sealing profile;

[0019] Fig. 2 is a perspective view of an extrusion tool for a further embodiment of a sealing profile;

[0020] Fig. 3a is a perspective view of a second embodiment of a sealing or edge protection profile;

[0021] Fig. 3b is a perspective view of a third embodiment of a sealing or edge protection profile and

[0022] Fig. 4 is a schematic representation of the manufacturing process.

[0023] Figure 1 shows a first embodiment of a sealing profile 1 for a motor vehicle, in particular for sealing a door frame against a vehicle door. As can be seen from the perspective view, the sealing profile 1 comprises a sealing section 2 with a hollow chamber 3 and an L-shaped fastening section 4 with a protruding retaining leg 5 for gripping a body flange (not shown). Contrary to what is shown, the retaining leg 5 can be designed essentially parallel to an opposite straight wall section 6 of the hollow chamber 3 in order to positively grip a corresponding body flange.By means of the sealing section 2, a gap, for example between a door frame and a door of a motor vehicle, can be bridged in a known manner, wherein in the closed position of the door, the sealing section 2 is clamped between the door and the door frame and slightly deformed, which ensures a reliable seal.

[0024] The sealing profile 1 is produced by extrusion from an elastomer, in particular a thermoplastic elastomer such as EPDM, and / or a thermoplastic, which basically results in an identical cross-section of the sealing profile 1 in the longitudinal direction. However, it has proven advantageous if the sealing profile 1 has local cross-sectional changes in cross-section and in the longitudinal direction at spaced-apart positions. Such local cross-sectional changes can, for example, be continuous profile openings which are arranged in the straight wall section 6 of the hollow chamber 3 at a distance from one another in cross-section and in the longitudinal direction. The profile opening 7 is numbered as an example. The profile openings 7 form, for example, ventilation openings for the hollow chamber 3, so that when the door to be sealed is closed, the air in the hollow chamber 3 can escape through the profile openings 7.The profile openings 7 can be selected in size and position such that, when the door is closed, a defined pressure increase occurs briefly in the hollow chamber 3, which causes the door to close gently. Due to the arrangement of the profile openings 7 in the straight wall section 6 opposite the retaining leg 5 of the fastening section 4, the profile openings 7 are not located in the visible area, which enables a visually appealing overall impression of the sealing profile 1 in the visible area.

[0025] As further local cross-sectional changes, the sealing profile 1 has several material thinnings in the form of grooves on the inside of the wall of the hollow chamber 3, of which groove 8 is numbered here as an example. The grooves 8, which are spaced apart from one another in the cross-section and in the longitudinal direction of the sealing profile 1, provide targeted predetermined bending points in the sealing section 2 of the sealing profile 1. This makes it possible to precisely adjust the deformation of the sealing section 2 in the closed position of the door. Since the predetermined bending points also reduce the counterforce and thus the sealing effect, the counterforce can be set differently in each section by specifically arranging corresponding predetermined bending points in the longitudinal direction of the sealing profile 1 and can be locally adapted to the respective requirements of the door to be sealed.Figure 2 shows a perspective view of an extrusion tool 9 for a further embodiment of a sealing profile. The extrusion tool 9 comprises a nozzle 10, the inner side 11 of which, in cross-section, essentially corresponds to the cross-section of the sealing profile to be extruded. For the sake of simplicity, a mandrel, which is necessary for producing a hollow chamber of the sealing profile shown in the following figures, is not shown. As can be seen from the illustration, channels spaced apart from one another in cross-section open out at the inner side 11 of the nozzle 10, of which the opening of the channel 12 is numbered here as an example.A pressurized, amorphous medium can be fed through the channels 12 to the material to be extruded and then applied against the material, displacing the material and creating the described local cross-sectional changes in the sealing profile 1 to be extruded. The amorphous medium is preferably a gas such as compressed air, which can be provided particularly easily. The channels 12 can be formed in the mouth region at right angles to the longitudinal direction of the nozzle 10 or to the extrusion direction, or at an angle thereto. As a result, the amorphous medium in the extrusion tool 9 is pressed laterally at a defined angle against the surface of the material of the sealing profile 1.

[0026] Figure 3a shows a perspective view of a second embodiment of a sealing profile 1'. The sealing profile T and the sealing profile 1" shown in Figure 3b are designed similarly to the sealing profile 1 shown in Figure 1. Similar elements of the sealing profiles 1', 1" are therefore identified by the same reference numerals and an additional apostrophe.

[0027] As can be seen from the illustration in Figure 3a, the sealing profile T also comprises a sealing section 2', shown here in partial section, with a hollow chamber 3', as well as a fastening section 4', which is formed by a holding leg 5' protruding from the sealing section 2' and running parallel to a straight wall section 6' of the sealing section 2'. In the exemplary embodiment shown, recesses in the form of blind holes are provided on an inner side of the holding leg 5', of which the recesses 13a, 13b are numbered here. A group of recesses 13a, 13b is arranged at the same position in the longitudinal direction of the sealing profile 1'. This results from the arrangement of the channels 12 on the inner side 11 of the nozzle 10 of the extrusion tool 9 shown in Figure 2.If, at the extrusion tool 9, compressed air is simultaneously applied through the channels 12 by means of a short pressure pulse against the sealing profile T currently arranged in the extrusion tool 9, one of the rows of recesses 13a shown in Figure 3a is created. If these pressure pulses are repeated during the extrusion of the sealing profile 1, the further rows of recesses 13b are created.

[0028] Figure 3b shows a perspective view of a third embodiment of a sealing profile 1". In contrast to the second embodiment shown in Figure 3a, the recesses 13c, 13d extend in the longitudinal direction of the sealing profile 1" in the form of longitudinal grooves, which are spaced apart from one another in the longitudinal direction in sections. This is achieved by applying compressed air via the channels 12 against the sealing profile 1" to be extruded over a longer period of time, instead of a short pressure pulse, and therefore material is displaced over a greater distance in the longitudinal direction.

[0029] The length of the recesses 13a, 13b, 13c, 13d in the longitudinal direction of the sealing profile T, 1" can therefore be adjusted by the duration of the compressed air supply. The depth of the material displacement can also be influenced by the magnitude of the pressure, which ranges from a superficial material displacement in the form of a groove to a profile opening or a through hole. These local cross-sectional changes can thus be provided particularly easily even at locations on the sealing profile that are not usually easily accessible by mechanical methods using a stylus. Since the channels can also be designed to be individually controlled differently and the pressure can be varied individually in each case, a wide variety of local cross-sectional changes spaced apart in the cross-section and in the longitudinal direction can be provided in a single work step during the extrusion of the sealing profile.

[0030] Figure 4 shows a schematic representation of a manufacturing process for profile openings. In the exemplary embodiment shown, the material of the sealing profile 1 to be extruded flows from top to bottom through the nozzle 10 along the inner side 11. Channels 12a, 12b are arranged in the nozzle 10 and lie opposite one another in the opening region to the inner side 11 of the nozzle 10. The channel 12a forms a supply channel for the amorphous medium, in particular the compressed air, and the channel 12b forms a discharge channel. By intermittently applying compressed air to the channel 12a, pieces of material of the sealing profile 1, of which piece 14 is numbered here, are displaced into the channel 12b and discharged during the extrusion. This makes it particularly easy to create profile openings in the sealing profile 1, of which profile opening 7 is numbered here.In a further embodiment not shown, alternatively only one channel can be provided as a feed channel, wherein the material of the sealing profile is displaced in all directions and thus also against the extrusion direction at the relevant location adjacent to the mouth of the channel 12a by the formless medium supplied under pressure, which also leads to permanent profile openings, grooves or recesses due to the still soft material in the extrusion tool 9 or in the nozzle 10.

[0031] Reference symbol list:

[0032] 1 , 1 ', 1 “ sealing profile

[0033] 2, 2' sealing section

[0034] 3, 3' hollow chamber

[0035] 4, 4' mounting section

[0036] 5.5' holding leg

[0037] 6, 6' Straight wall section

[0038] 7 Profile opening

[0039] 8 grooves

[0040] 9 Extrusion tool

[0041] 10 nozzle

[0042] 1 1 Inside of the nozzle

[0043] 12, 12a, 12b channel

[0044] 13a, 13b, 13c, 13d recesses

[0045] 14 pieces of material

Claims

Patent claims:

1. A method for producing a sealing or edge protection profile (1; 1'; 1"), in particular a sealing or edge protection profile for a motor vehicle, wherein the sealing or edge protection profile (1; 1'; 1") is produced by extrusion in an extrusion tool (9), characterized in that in the extrusion tool (9) and / or in the extrusion direction downstream of the extrusion tool (9) local cross-sectional changes (7; 8; 13a; 13b; 13c; 13d) are produced in the sealing or edge protection profile (1; 1'; 1") by a formless medium supplied under pressure.

2. Method according to claim 1, characterized in that the formless medium is a fluid, in particular a liquid or a gas.

3. Method according to claim 1 or 2, characterized in that the formless medium is pressed laterally against the surface of the sealing or edge protection profile (1; 1 '; 1 ") in the extrusion tool (9) and / or in the extrusion direction after the extrusion tool (9).

4. Method according to one of claims 1 to 3, characterized in that as local cross-sectional changes (7; 8; 13a; 13b; 13c; 13d) in the sealing or edge protection profile (1; 1'; 1") material thinnings (8), in particular in the form of predetermined bending points, profile openings (7), in particular in the form of through holes, and / or recesses (13a; 13b; 13c; 13d) are produced.

5. Method according to one of claims 1 to 4, characterized in that the cross-sectional changes (7; 8; 13a; 13b; 13c; 13d) in the sealing or edge protection profile (1; 1 '; 1 ") are produced in such a way that they are in the longitudinal direction of the sealing or edge protection profile (1; 1 '; 1 ") and / or in the Cross-section of the sealing or edge protection profile (1; 1'; 1") are spaced apart from one another. Method according to one of claims 1 to 5, characterized in that the pressure of the supplied formless medium is varied during the extrusion. Method according to one of claims 1 to 6, characterized in that the formless medium is supplied intermittently. Extrusion tool (9) for forming a sealing or edge protection profile (1; 1 '; 1 "), in particular a sealing or edge protection profile for a Motor vehicle, with a nozzle (10) through which material of the sealing or Edge protection profile (1; 11") can be pressed out during extrusion, characterized in that at least one channel (12; 12a; 12b) for a formless medium supplied under pressure is provided in the nozzle (10) and / or downstream of the nozzle (10) in the extrusion direction. Extrusion tool (9) according to claim 8, characterized in that the at least one channel (12; 12a; 12b) opens out on an inner side (11) of the nozzle (10). Extrusion tool (9) according to claim 8 or 9, characterized in that a plurality of channels (12; 12a; 12b) for a formless medium supplied under pressure open out on the inner side (11) of the nozzle (10), wherein the channels (12; 12a; 12b) in the nozzle (10) can be formed separately or at least partially connected to one another.

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