SEALING RING

Description

[0001] The invention relates to a sealing ring comprising a supporting body and at least one sealing body.

[0002] For small electrical devices, such as household appliances, very simple sealing systems are often used for sealing. A key requirement here is that they must be cost-effective. Sealing elements are often integrated directly into the housing components of the small devices. There is no provision for replacing such sealing elements. Furthermore, the sealing elements are often of inferior quality, meaning that the sealing effect of the sealing system cannot be maintained over the intended service life of the small device. The use of sealing elements as commonly used in industry is ruled out due to the high material costs for the sealing element and supporting body.

[0003] From GB 2 272 733 A a sealing ring with a support body and a sealing body is known, wherein the support body is formed in several parts and has a housing element and an inner body, wherein the sealing body is fixed between the housing element and the inner body and wherein the inner body is held in a form-fitting manner on the housing element.

[0004] The invention is based on the object of providing a sealing ring which is particularly cost-effective and at the same time enables a sealing effect over a long period of use.

[0005] This object is achieved by the features of claim 1. The subclaims refer to advantageous embodiments.

[0006] To achieve the object, the sealing ring comprises a support body and at least one sealing body, wherein the support body has at least one housing element made of plastic, wherein the housing element has a radial flange and an axial flange and wherein the housing element accommodates the sealing body.

[0007] The sealing body can be bonded to the housing element by a material fit. Such a sealing ring is simple and cost-effective to manufacture. The material fit securely connects the sealing body and the housing element. The sealing body and housing element can be shaped particularly simply. The material fit can be created using an adhesive. The material fit is preferably achieved by melting the plastic in places, for example, through a welded joint. This can be achieved, for example, by friction welding.

[0008] The sealing body can be connected to the housing element with a form-fitting connection. With a form-fitting connection, the process steps required for a material-to-material bond are eliminated. Furthermore, pretreatment of the joints with problematic substances, as is often required for a material-to-material bond, is eliminated.

[0009] The sealing body can extend along the end face of the radial flange and, at least in sections, along the axial flange of the housing element. In this configuration, the sealing body functions as a dynamic seal against a rotating machine element to be sealed, for example, a shaft, and as a static seal against another machine element to be sealed, for example, a housing. The sealing body can be designed to be compressible, thereby reinforcing the clamping effect of the sealing ring in the housing. Furthermore, the sealing body shields the housing element on one side of the gap between the two machine elements.

[0010] According to the invention, the support body is constructed in several parts and has an inner body made of plastic. The housing element accommodates the inner body and the sealing body arranged between the radial flange and the inner body. In this embodiment, the sealing body is clamped between the inner body and the housing element and thus fixed.

[0011] The housing element can be designed as an L-shaped ring. The inner body is preferably annular and, after assembly, comes into contact with the radial flange and the inward-facing side of the axial flange. In this configuration, the inner body forms a clamping body.

[0012] Because the support body, or rather the components of the support body, are made of plastic, the support body can be manufactured particularly cost-effectively. It is particularly advantageous that the sealing body is held in a form-fitting manner between the inner body and the housing element. This eliminates the need to design the material of the inner body and the housing element in such a way that a material-to-material connection of the sealing body to the support body is possible. In this respect, in the embodiment according to the invention, for example, sealing bodies made of PTFE which are held exclusively by positive locking between the inner body and the housing element.

[0013] The support body can form a static seal on the outer circumference or along a front side associated with the housing. The static seal can be implemented directly by the support body or the housing element. In particular, selecting a suitable plastic can provide sufficient sealing between the support body and the housing. Alternatively, a static seal made of a different material can be associated with the housing element. In this case, it is particularly conceivable to form a static seal made of a thermoplastic material using two-component injection molding.

[0014] A thermoplastic is preferably used as the material for the inner body and the housing element, so that the inner body and housing element can be manufactured using an injection molding process. Depending on the intended use, it is conceivable to manufacture the housing element and the inner body from polyethylene (PE), polyamide (PA), polylactide (PLA), polypropylene (PP), polycarbonate (PC), acrylonitrile butadiene styrene (ABS), polymethyl methacrylate (PMMA), polyethylene terephthalate (PET), or polytetrafluoroethylene (PTFE). Furthermore, it is conceivable to form the housing element and inner body from a thermoset, in which case fiber reinforcement can also be provided.

[0015] In particular, it is conceivable to provide the housing element and inner body from different plastics. The material of the housing element is selected so that it can be securely fixed in a housing bore. The material for the inner body can be chosen to create a particularly strong connection between the housing element and inner body. Furthermore, a comparatively soft plastic can also be selected for the housing element, which enables particularly good static sealing with the housing.

[0016] The inner body can be made of an elastic material, such as an elastomer, so that the inner body is held in the housing element with elastic preload. This results in a secure connection between the inner body, sealing disc, and housing element.

[0017] According to the invention, the inner body is held positively to the housing element. In this embodiment, at least the inner circumference of the axial flange and / or the outer circumference of the inner body has positive-locking elements. According to an advantageous embodiment, the inner circumference of the axial flange has annular recesses in the form of a groove, and the inner body has annular elevations on its circumference that are congruent with the recesses. The elevations and depressions can also be formed only in segments. After assembly of the inner body, the elevations of the inner body engage in the recesses of the axial flange of the housing element and thus fix the inner body in the housing element in a positive-locking and captively manner. The elevations can be trapezoidal and, in particular, sawtooth-shaped.

[0018] Further possibilities for a positive connection are provided by a screw connection, in which the inner body has an external thread and the housing element has an internal thread, and by a bayonet lock.

[0019] The inner body can be held force-fittingly to the housing element. The force-fitting connection can be implemented in addition to a form-fitting connection. For this purpose, the inner diameter of the axial flange can be undersized and / or the outer diameter of the inner body can be oversized. This means that the inner body can only be mounted on or in the housing element with force. After assembly, the inner body is force-fittingly fixed to the housing element, clamping the sealing body between the inner body and the housing element. In this respect, the sealing body is held captively between the inner body and the housing element. To increase the clamping effect, the contacting surfaces of the inner body and the housing element can be roughened.

[0020] The inner body can be held firmly in place on the housing element. The firm bond can be provided in addition to the positive connection and / or the frictional connection. In this case, it is conceivable for the inner body to be firmly bonded to the housing element by means of an adhesive connection or a welded connection. The firm bond results in a particularly strong connection between the inner body and the housing element. To create the firm bond between the inner body and the housing element, the following processes are particularly conceivable: gluing, hot staking, hot element welding, high-frequency welding, laser transmission welding, circular welding, rotational friction welding, ultrasonic welding, vibration welding, and hot gas welding. A particular advantage of the welding processes is that they enable a firm bond between the inner body and the housing element without the use of an additive.

[0021] The sealing body can be designed as a sealing disc. Such a sealing body is particularly simple and cost-effective to manufacture. For example, it is conceivable to manufacture the sealing body cost-effectively from a tubular semi-finished product. Particularly if the sealing body functions solely as a dust seal and is intended to prevent the penetration of contaminants into a sealed space, it is usually sufficient to design the sealing body as a sealing disc. In this case, the sealing disc can be made of felt or a similar textile material, for example. For simple sealing tasks where grease needs to be retained, the sealing disc can be made of elastomeric material.

[0022] According to an advantageous embodiment, the sealing body is made of a textile sheet material. Such a textile sheet material is, for example, a nonwoven fabric in the form of a web. To increase the sealing effect, the textile sheet material can be impregnated with PTFE. Such a PTFE nonwoven has an excellent sealing effect against penetrating dirt and splash water. Furthermore, a PTFE nonwoven has particularly low friction, so that only minimal heat development occurs in the area of ​​the sealing ring during operation. This is particularly advantageous in conjunction with the support body made of plastic. It is also conceivable to use a coated nonwoven fabric. In a further embodiment, the textile sheet material can be designed to be electrically conductive.If the support body is suitably conductive, this design is advantageous, for example, when static electricity needs to be dissipated. Both the support body and the sealing body can be made of PTFE.

[0023] Furthermore, it is conceivable to form the sealing body from cellulose, especially paper. Such materials are known, for example, in connection with flat gaskets. The sealing body can also be formed from organic sheet material, such as leather or the like.

[0024] Both the supporting body and the sealing body can be made of recycled material. The supporting body can also be made of renewable raw materials, such as cardboard. The sealing body can, for example, be made of a flat elastomer material that is left over during the production of higher-quality seals.

[0025] Alternatively, the sealing body can have a disc-shaped fastening section and an elastomeric sealing lip. Both the disc-shaped fastening section and the sealing lip can be made of the same elastomeric material and formed from the same material and in one piece. Alternatively, the disc-shaped fastening section can be made of a different material than the sealing lip, with the fastening section and sealing lip then being integrally bonded to one another. The sealing lip can be designed such that it bears against the machine element to be sealed under radial preload, forming a seal. An annular spring or the like can be provided to enhance the sealing effect. In this respect, the sealing ring can also be designed as a radial shaft seal.

[0026] The sealing lip can be provided with a profile, for example a spiral groove, on the section associated with the shaft.

[0027] The radial section of the housing element can be provided with a profile on the side facing the inner body and / or the inner body can be provided with a profile on the side facing the radial section. The profile can consist of congruent elevations and depressions. The profile deforms the sealing body arranged between the inner body and the housing section in sections, thereby improving the clamping effect of the sealing body in the support body. According to an advantageous embodiment, a wave-shaped profile results, so that the sealing body is also wave-shaped in this area and is clamped between the housing element and the inner body.

[0028] According to the invention, sealing elements are arranged between the inner body, the sealing body, and the housing element. The additional sealing elements can be in the form of O-rings, for example. The sealing elements, which are arranged between the inner body and the sealing body, or between the sealing body and the housing element, improve the sealing of the sealing ring, so that no medium to be sealed can penetrate between the components of the sealing ring.

[0029] The sealing body can be firmly bonded to the inner body and / or housing element. This can be achieved by means of an adhesive or welded joint, in addition to the measures described above. This bonded connection can reduce the risk of static leakage between the sealing ring components.

[0030] A separate static seal can be assigned to the outer circumference of the axial flange. The static seal can be held frictionally on the outer circumference of the housing element. Alternatively, the static seal can also be firmly bonded to the housing element. The static seal can consist of an annular elastomer element with a thin wall thickness. Alternatively, the static seal can be designed in the form of a sealing varnish that is sprayed onto the housing element.

[0031] The sealing ring can be assigned a plain bearing on which the shaft can be supported to relieve the load on the sealing body.

[0032] The sealing ring according to the invention is particularly suitable for use in small electrical appliances. A sealing arrangement according to the invention comprises a small electrical appliance and a sealing ring, wherein the small electrical appliance has a housing from which a shaft protrudes, and wherein the sealing ring is arranged in the gap between the housing and the shaft and is fixed in the housing. The small electrical appliance can be a household appliance, for example, a fruit press, a blender, a hand blender, or a food processor. It is also conceivable for the small electrical appliance to be a power tool.

[0033] An adapter ring can be assigned to the support body. This adapter ring is preferably frictionally attached to the outer circumference of the housing element. The adapter ring allows the housing element to be adapted to different diameters of the housing bore in which the sealing ring is to be mounted. The adapter ring is also made of plastic. The adapter ring can be attached to the outer circumference of the housing element with a positive fit using appropriate profiling, a frictional fit, and / or a material fit using an adhesive or welded joint.

[0034] A flange can also be formed from the housing element. The flange can be annular and protrude radially outward from the sealing ring. The sealing ring can be secured to a housing using the flange. The flange can have openings for fastening devices.

[0035] A sensor can be associated with the sealing ring. The sensor can be located between the inner body and the housing element, where it can be clamped together with the sealing body. Alternatively, the sensor can also be associated with the inner body and / or the housing element. It is also conceivable to arrange the sensor within the inner body or the housing element. The sensor can, for example, detect the temperature of the housing or shafts, the shaft speed, or the medium penetrating the sealing ring.

[0036] Some embodiments of the sealing ring according to the invention are explained in more detail below with reference to the figures. These show, schematically: Fig. 1Seal rings with sealing disc in section; Fig. 2A sealing ring with sealing disc in section; Fig. 3A sealing ring with sealing lip in section; Fig. 4A sealing ring with sealing elements; Fig. 5Sealing rings with static seal; Fig. 6A sealing ring with material bond between housing element and inner body; Fig. 7A sealing ring with integrated plain bearing; Fig. 8A sealing ring with adapter ring; Fig. 9A sealing ring with a sealing body bonded to the support body in a material bond; Fig. 10A sealing ring with a positively integrated sealing body; Fig. 11A sealing ring with a positively integrated sealing body; Fig. 12A sealing ring with a sealing body arranged in a form-fitting manner on the support body; Fig. 13A sealing ring whose support body has a housing element and an inner body. Figure 1 shows three non-inventive embodiments of a sealing ring 1, comprising a support body 2 and a sealing body 3. The support body 2 is formed in several parts and has a housing element 4 made of plastic and an inner body 5 made of plastic. The housing element 4 has a radial flange 6 and an axial flange 7, and the housing element 4 accommodates the inner body 5 and the sealing body 3 arranged between the radial flange 6 and the inner body 5.

[0037] In the embodiments, the inner body 5 is held both force-fitting and form-fitting on the housing element 4.

[0038] For this purpose, the axial flange 7 of the housing element 4 on the side facing the inner body 5 and the inner body 5 on its outer circumference are provided with form-locking elements 8. In the first embodiment, the inner body 5 has annular, sawtooth-shaped elevations that engage in congruently shaped recesses that are made in the axial flange 7. In the second embodiment, the inner body 5 has rectangular elevations that engage in congruently shaped recesses that are made in the axial flange 7. In the third embodiment, the inner body 5 has semicircular elevations that engage in congruently shaped recesses that are made in the axial flange 7.

[0039] The radial flange 6 of the housing element 4 and the inner body 5 are provided with a wave-shaped profiling 11 on the sides facing each other, so that the sealing body 3 is deformed in a wave-like manner in this area.

[0040] When designing according to Figure 1 The sealing body 3 is designed as a sealing disc. The sealing disc, in turn, is made of a nonwoven fabric impregnated with PTFE. Therefore, the sealing body 3 is made of a textile sheet material.

[0041] Figure 2 shows a non-inventive alternative embodiment of the sealing ring 1 according to Figure 1 , in which the inner body 5 is connected to the housing element 4 via a thread.

[0042] Figure 3 shows a non-inventive alternative embodiment of the sealing ring 1 according to Figure 1 , in which the sealing body 3 has a disc-shaped fastening section 9 and an elastomeric sealing lip 10. The disc-shaped section 9 and the elastomeric sealing lip 10 are made of different materials and are integrally bonded to one another. The sealing lip 10 is provided with an annular coil spring 14.

[0043] Figure 4shows a sealing ring 1 according to the invention according to Figure 1 , in which sealing elements 12 are arranged between the inner body 5, the sealing body 3, and the housing element 4. The sealing elements 12 are shaped as O-rings.

[0044] Figure 5 shows sealing rings 1 according to the invention according to Figure 1 , which are additionally provided with a static seal 13. In the first embodiment, the static seal 13 is in the form of a form-fitting element. In the second embodiment, the static seal 13 is in the form of a separate sealing element, here in the form of an O-ring. In the third embodiment, the static seal 13 is in the form of a sealing varnish applied to the outer circumference of the housing element 4.

[0045] Figure 6 shows a sealing ring 1 according to Figure 1, in which the inner body 5 is held firmly to the housing element 4. For this purpose, the inner body 5 is connected to the housing element 4 by means of a welded joint 15 in the region of the axial flange 7 and the outer circumference of the inner body 5.

[0046] Figure 7 shows a non-inventive sealing ring 1 according to Figure 1 , wherein the inner body 5 forms a sliding bearing 16 in the form of a sliding ring, which projects radially inwards. Figure 7 The plain bearing 16 shown can in principle be used in all previously shown configurations, in particular in the configurations according to Figures 1 to 5 be provided.

[0047] Figure 8 shows a non-inventive sealing ring 1 according to Figure 1 , in which an adapter ring is arranged on the outer circumference of the housing element 4. The adapter ring is held force-fittingly on the housing element 4.

[0048] Figure 9shows a sealing ring 1 not according to the invention, comprising a support body 2 and a sealing body 3. The support body 2 has a housing element 4 made of plastic. The housing element 4 has a radial flange 6 and an axial flange 7. The sealing body 3 is firmly bonded to the end face of the radial flange 6 facing the axial flange 7. The firmly bonded connection is designed as a welded joint and was produced by friction welding.

[0049] According to an alternative embodiment, the sealing body 3 is firmly attached to the end face of the radial flange 6 facing away from the axial flange 7 and extends in sections over the axial flange 7 in order to form a static seal there.

[0050] The sealing body 3 is designed as a sealing disc. The sealing disc, in turn, is made of PTFE-impregnated nonwoven fabric. Therefore, the sealing body 3 is made of a textile sheet material. The supporting body 2 is made of injection-moldable plastic.

[0051] Figure 10 shows a non-inventive development of the Figure 9 shown sealing ring 1. In this embodiment, the axial flange 7 was plastically deformed after insertion of the sealing body 3, so that the sealing body 3 borders the housing element 4 on both end faces. As a result, the sealing body 3 is positively integrated into the housing element 4. The plastic deformation of the housing element 4 can be achieved by briefly heating it above the melting point of the plastic used for the housing element 4.

[0052] Figure 11 shows a non-inventive, alternative embodiment of the Figure 10shown sealing ring 1. In this embodiment, the sealing body 3 has elevations 17 on both end faces, which improve the positive integration of the sealing body 3 into the housing element 4.

[0053] Figure 12 shows a sealing ring 1 not according to the invention, comprising a support body 2 and a sealing body 3. The support body 2 has a housing element 4 made of plastic. The housing element 4 has a radial flange 6 and an axial flange 7. The sealing body 3 is positively fastened to the end face of the radial flange 6 facing away from the axial flange 7. The positive connection is made via push-button-like projections 18, which protrude through openings 19 made in the sealing body 3, wherein the projections 18 engage with a locking element 20.

[0054] In this embodiment, the sealing body 3 can extend in sections over the axial flange 7 in order to form a static seal there.

[0055] Figure 13 shows a non-inventive embodiment of a sealing ring 1, comprising a support body 2 and a sealing body 3. The support body 2 is formed in several parts and has a housing element 4 formed from plastic and an inner body 5 formed from plastic.

[0056] The housing element 4 has a radial flange 6 and an axial flange 7 and the housing element 4 accommodates the inner body 5 and the sealing body 3 arranged between the radial flange 6 and the inner body 5.

[0057] In these embodiments, the inner body 5 is held firmly to the housing element 4. The firmly bonded connection is formed as a welded joint, but can also be an adhesive connection. After positioning the sealing body 3, the inner body 5 is inserted into the housing element 4, for example, bonded firmly to the housing element 4 by friction welding.

[0058] Alternatively, it is also conceivable that the inner body 5 deforms during the joining process and thereby clamps the sealing body 3.

[0059] The sealing body 3 is designed as a sealing disc. The sealing disc, in turn, is made of a nonwoven fabric impregnated with PTFE. Therefore, the sealing body 3 is made of a textile sheet material.

[0060] The sealing rings 1 shown in the previously described figures are particularly suitable for use in devices with plastic housings, for example, in handheld DIY tools and household appliances. The sealing ring 1 is suitable for sealing shafts that protrude from the plastic housing.

[0061] An advantageous device comprises a plastic housing in which a shaft is mounted, wherein in the gap between the plastic housing and the shaft a sealing ring 1 according to one of the Figures 1 to 13 shown designs.

Claims

1. Sealing ring (1) comprising a support body (2) and at least one sealing body (3), wherein the support body (2) has at least one housing element (4) formed from plastic, wherein the housing element (4) has a radial flange (6) and an axial flange (7) and wherein the housing element (4) receives the sealing body (3), wherein the support body (2) is of multi-part design and has an inner body (5) formed from plastic, wherein the housing element (4) receives the inner body (5) and the sealing body (3), which is arranged between the radial flange (6) and the inner body (5), wherein the inner body (5) is held in a form-fitting manner on the housing element (4), wherein the axial flange (7) of the housing element (4) is provided with form-fitting elements (8) on the side facing towards the inner body (5), characterized in that sealing elements (12) are arranged between the radial flange (6) of the housing element (4) and the sealing body (3) and between the sealing body (3) and the inner body (5).

2. Sealing ring according to Claim 1, characterized in that the inner body (5) is held in a force-fitting manner on the housing element (4).

3. Sealing ring according to one of Claims 1 or 2, characterized in that the inner body (5) is held in a cohesively bonded manner on the housing element (4).

4. Sealing ring according to Claim 3, characterized in that the inner body (5) is joined to the housing element (4) by means of a welded connection.

5. Sealing ring according to one of Claims 1 to 4, characterized in that the sealing body (3) is in the form of a sealing disc.

6. Sealing ring according to one of Claims 1 to 5, characterized in that the sealing body (3) has a discshaped fastening portion (9) and an elastomeric sealing lip (10).

7. Sealing ring according to one of Claims 1 to 6, characterized in that the sealing body (3) is formed from a textile sheet material.

8. Sealing ring according to one of Claims 1 to 7, characterized in that a static seal (13) is assigned to the axial flange (7) on the outer circumference.