Method for producing a seal, seal, and housing having a seal

Abstract

The invention relates to a method for producing a seal (1), in particular a housing seal, having the steps of: a) applying a sealing material in the form of a first sealing bead (2) to the surface (3) of a first component (4), in particular a first housing part, b) applying at least one additional sealing bead (5) to the first sealing bead (2) before the first sealing bead is cured, c) curing the sealing beads (2, 5), and d) pressing the sealing beads (2, 5) lying one above the other with the aid of an additional component (6), in particular an additional housing part. The invention further relates to a seal (1) and to a housing (10) having a seal (1) according to the invention.

Description

[0001] Description

[0002] Title:

[0003] Method for manufacturing a seal, seal and housing with seal

[0004] The invention relates to a method for manufacturing a seal, in particular a housing seal. Furthermore, the invention relates to a seal, in particular a housing seal, and a housing with a seal.

[0005] A preferred application area of ​​the invention is multi-part housings of components which have seals arranged between two housing parts to protect against environmental influences such as particles and media.

[0006] State of the art

[0007] A multi-part housing, comprising at least two housing parts, such as a base and a lid, must be joined. During joining, a gap typically remains between the two housing parts, through which dirt and moisture can penetrate. To prevent this, a seal can be formed in the gap. This can be done in various ways.

[0008] For example, if two housing parts need to be firmly joined simultaneously using a seal, "form-in-place" (FIP) seals are particularly suitable. These seals differ in their cross-sectional shape (width, height, and / or number of sealing lips), the resulting sealing width, and the surface pressure when compressed. To create an FIP seal, a sealing material is typically applied to a first housing part and then compressed during the subsequent joining process with the help of the second housing part.

[0009] It is well known that high surface pressure improves the sealing performance of a seal. However, this can be limited by factors such as the maximum permissible stress of the sealing material, its swelling and / or thermal expansion behavior, the size of the gap to be sealed, the tolerances of the mating components, and the like. The cross-sectional shape of the seal then offers potential for optimization in order to ensure sufficient sealing performance even under high corrosive loads and / or high pressure differentials. The cross-sectional shape, in turn, depends significantly on the sealing material used and the manufacturing process of the seal, especially the individual process parameters.

[0010] FIP gaskets are manufactured using a nozzle to apply the sealing material to the surface of a housing component. During application, the nozzle is moved relative to the surface of the housing component. Relevant process parameters are therefore those that influence the application of the sealing material and the movement of the nozzle. Due to the process, FIP gaskets have a cross-sectional shape that is round-convex on its upper surface, typically across the entire width, or at least at the edges. This round-convex shape often leads to unfavorable surface pressure on the gasket during subsequent assembly.

[0011] The present invention is concerned with the objective of providing a seal with an optimized cross-sectional shape and a method for producing a seal with an optimized cross-sectional shape that meets high sealing requirements.

[0012] To solve the problem, the method with the features of claim 1 is specified. Advantageous embodiments of the invention are described in the dependent claims. Furthermore, a seal and a housing with a seal are specified.

[0013] Disclosure of the invention

[0014] A method for manufacturing a seal, in particular a housing seal, is proposed, comprising the steps of: a) applying a sealing material in the form of a first sealing bead to a surface of a first component, in particular a first housing part, b) applying at least one further sealing bead to the first sealing bead before it has hardened, c) hardening the sealing beads and d) pressing the overlapping sealing beads together using another component, in particular another housing part.

[0015] In the proposed method, the seal is applied in multiple layers, particularly two layers. When at least one additional bead of sealant is applied to the first bead, the latter is flattened because the weight of the overlying bead forces sealant material from the center to the two edges of the first bead. This is especially true when the two sealant beads are applied immediately one after the other, i.e., "wet-on-wet." The cross-sectional shape of the superimposed sealant beads thus approaches a box shape and therefore moves away from a shape that is round-convex on its upper surface. The "wet-on-wet" application also contributes to optimal bonding of the sealant material between the superimposed sealant beads.

[0016] When at least one additional bead of sealant is applied to the first bead, the latter forms lateral bulges, which in turn lead to lateral constrictions in the contact area with the bead above. These constrictions allow the sealant to spread unhindered when the overlapping beads are subsequently pressed together. After the sealant has fully cured, the lateral constrictions have a positive effect on the swelling and / or thermal expansion behavior of the seal.

[0017] The lateral constrictions also result in areas of increased surface pressure being formed during compression. These areas—referring to each contact surface of the seal with a component or housing part—are located at the two edges, so that the surface pressure is higher here than, for example, in the center. Areas of increased surface pressure can otherwise only be achieved with a multi-lip seal, which is complex and therefore expensive to manufacture. With the present method, the advantages of a multi-lip seal, in particular increased sealing performance, can be achieved using simple means.

[0018] The application of the sealing beads is preferably carried out using a dispersion process. This process offers great flexibility regarding the shape and position of the seal, while also minimizing tooling costs. Therefore, the dispersion process is particularly suitable for smaller production runs and / or prototype phases. Another advantage of the dispersion process is that individual layers of sealing material can be applied sequentially. This can positively influence the final shape of the seal.

[0019] Furthermore, a nozzle is preferably used to apply the sealing beads. The nozzle allows the sealing material to be applied particularly easily as a sealing bead. The nozzle is preferably moved parallel to the surface of the first component, especially the first housing part, during application. A robot arm and / or a gantry-like traversing system can be used to move the nozzle. The nozzle is then moved parallel to the surface of the component or housing part by this system.

[0020] Preferably, the nozzle used to apply the sealing beads has an opening cross-section that deviates from a circular shape. The cross-sectional shape of the sealing beads can be controlled via the nozzle opening cross-section. In particular, a less round cross-sectional shape of the sealing beads can be achieved by moving away from a circular nozzle opening cross-section.

[0021] Furthermore, it is proposed that the nozzle be positioned at an angle α relative to the surface of the first component, particularly the first housing part, when applying the sealing beads. The cross-sectional shape of the sealing beads can also be influenced by the nozzle's angle of inclination. Preferably, the angle α is < 90°, more preferably < 80°, further preferably < 70°, and most preferably < 60°.

[0022] Furthermore, preferably, when applying at least one additional sealing bead, at least one process parameter is changed, in particular the distance of the nozzles to the surface of the first component, especially the first housing part, the traverse speed of the nozzle and / or the sealing material discharge.

[0023] The aforementioned process parameters – individually or in combination – enable an optimized multi-layered seal structure, leading to the aforementioned advantages.

[0024] Furthermore, a seal, in particular a housing seal, is proposed which is arranged in a gap between two components, especially between two housing parts, and is pressed between them. The seal has a cross-sectional shape formed from at least two overlapping sealing beads, which has lateral constrictions in the contact area of ​​two sealing beads.

[0025] The proposed seal can be manufactured, in particular, using the previously described method according to the invention, thus achieving the same advantages. In particular, the multi-layered structure of the seal allows for increased surface pressure in the edge regions, comparable to that of a multi-lip seal. This results in a high degree of sealing performance. Furthermore, the lateral constrictions permit swelling and / or thermally induced expansion of the seal without significantly affecting the surface pressure and therefore the sealing performance.

[0026] Furthermore, a housing is proposed comprising a first housing part and a second housing part, as well as a seal according to the invention. The seal is arranged in a gap between the two housing parts and pressed between them.

[0027] The invention and its advantages are explained in more detail below with reference to the accompanying drawings. These show:

[0028] Fig. 1 shows a schematic representation of a system for manufacturing a seal, Fig. 2 shows a cross-section through a seal manufactured according to the inventive method before pressing,

[0029] Fig. 3 shows a cross-section through the seal of Figure 2 after compression and

[0030] Fig. 4 shows a cross-section through a housing with a seal according to the invention.

[0031] Detailed description of the drawings

[0032] Figure 1 shows a system for manufacturing a seal 1 according to the invention. The system comprises a portal-like transport device 14, on which a container 13 filled with a sealing material and a nozzle 7 for dispensing the sealing material from the container 13 are arranged. A component 4 is arranged below the nozzle 7, which can in particular be a housing part 11 of a multi-part housing 10. Such a housing 10 is shown by way of example in Figure 4. The housing part 11, together with another housing part 12, defines a gap 8 in which a seal 1 is formed, which is designed according to the invention or has been manufactured according to a method according to the invention.

[0033] In the method according to the invention, a first sealing bead 2 is formed on a surface 3 of the component 4, preferably with the aid of a nozzle 7, as shown by way of example in Figure 1. Immediately afterwards, at least one further sealing bead 5 is applied to the first sealing bead 2. The seal 1 to be produced is therefore formed from at least two layers of sealing material. Subsequently, in a joining process, the sealing material is pressed between the component 4 and another joining partner.

[0034] Figure 2 shows, by way of example, two superimposed sealing beads 2, 5 for forming a seal 1 according to the invention before crimping. The cross-sectional shape has lateral constrictions 9 in the contact area of ​​the two sealing beads 2, 5 (see dashed line). After crimping, these are even more clearly visible, as shown by way of example in Figure 3. The crimping is carried out with the aid of a further component 6, which can in particular be a further housing part 12 (see Figure 4).

[0035] The cross-sectional shape of the seal 1, achieved by means of the overlapping sealing beads 2, 5, not only leads to the desired lateral constrictions 9, but also to a surface pressure that varies across the width of the seal 1. This is because the pressure is locally increased in edge regions 15. This means that an effect is achieved that is similar to that of a multi-lip seal. The seal 1 is therefore particularly suitable for applications with increased sealing requirements.

Claims

Claims 1. Method for producing a seal (1), in particular a housing seal, comprising the steps of: a) applying a sealing material in the form of a first sealing bead (2) to a surface (3) of a first component (4), in particular a first housing part, b) applying at least one further sealing bead (5) to the first sealing bead (2) before it has cured, c) curing the sealing beads (2, 5) and d) pressing the overlapping sealing beads (2, 5) together using a further component (6), in particular a further housing part.

2. Method according to claim 1, characterized in that the application of the sealing beads (2, 5) is carried out in a dispersion process.

3. Method according to claim 1 or 2, characterized in that a nozzle (7) is used to apply the sealing beads (2, 5), which is preferably moved parallel to the surface (3) of the first component (4), in particular the first housing part, during application.

4. Method according to claim 3, characterized in that the nozzle (7) used for applying the sealing beads (2, 5) has an opening cross-section that deviates from a circular shape.

5. Method according to claim 3 or 4, characterized in that the nozzle (7) is positioned at an angle (a) to the surface (3) of the first component (4), in particular the first housing part, when applying the sealing beads (2, 5), wherein the angle (a) is preferably < 90°, preferably < 80°, further preferably < 70°, and particularly preferably < 60°.

6. Method according to one of claims 3 to 5, characterized in that when applying the at least one further sealing bead (5) at least one process parameter is changed, in particular the distance of the nozzles (7) to the surface (3) of the first component (4), in particular of the first housing part, the traverse speed of the nozzle (7) and / or the sealing material discharge.

7. Seal (1), in particular a housing seal, which is arranged in a gap (8) between two components (4, 6), in particular between two housing parts, and is pressed between them, having a cross-sectional shape formed from at least two overlapping sealing beads (2, 5), which has lateral constrictions (9) in the contact area of ​​two sealing beads (2, 5).

8. Housing (10) comprising a first housing part (11) and a second housing part (12) as well as a seal (1) according to claim 7, wherein the seal (1) is arranged in a gap (8) between the two housing parts (11 , 12) and is pressed through the two housing parts (11 , 12).

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