PLASTIC COMPOSITE COMPOSITE COMPOSITE DEVICE

Description

[0001] The invention relates to a device according to the preamble of claim 1. State of the art

[0002] Today's competitive pressure forces companies to examine existing manufacturing processes and products for potential cost savings. Wherever possible, time-consuming and labor-intensive steps in the production of complex metal components are bypassed by simplifying products to enable automated manufacturing. There is also a trend to replace more expensive metal components with cheaper plastic parts. However, a problem with this is that the cheaper plastic parts very often fail to meet the required stability standards. For this reason, the plastic parts typically need to have greater wall thicknesses than their metal counterparts.

[0003] US 7,108,295 discloses a composite coupling for use in assembling a restricted connection between large-diameter pipes, i.e., diameters greater than approximately 40 cm, with external complementary clamping grooves axially spaced from the pipe ends. The composite coupling has first and second retaining grooves inside the coupling, each axially spaced from the pipe ends. These are accessible from the outside through holes through which a retaining wedge can be inserted. An internal stop is provided centrally inside the coupling, against which the ends of the pipes to be joined rest. Grooves for receiving an O-ring are provided between the internal stop and the retaining grooves. The cylindrical composite coupling has a plurality of concentrically arranged layers of wound filaments in a thermoset polymer matrix.

[0004] EP-A-1 400 141 relates to a coupling for the tensile-resistant joining of two tubes made of plastic material. The tubes are provided with flanges at their opposite ends, and a sleeve is arranged around each tube. The two sleeves and the flanges located between the sleeves are surrounded by a further outer sleeve. A groove is formed on the outer circumference of each sleeve surrounding a tube, which is positioned opposite a groove formed on the inner circumference of the outer sleeve, with a locking element being provided in each pair of opposing grooves. This prevents the sleeves from moving relative to each other in the longitudinal direction of the tubes. The coupling is further characterized in that the flanges abut each other and each sleeve can be loosely fitted around each tube, with one end abutting against the flange of the tube.Near the grooves are holes through which locking elements in the form of cords or bands made of plastic material can be inserted. These cords or bands prevent the sleeves from moving lengthwise along the pipes relative to the outer sleeve. The sleeves are made of fiberglass-reinforced plastic.

[0005] The inner circumference of the sleeve features additional circular grooves, each designed to hold an O-ring. When the coupling is assembled, these O-rings form a seal between the inner circumference of the outer sleeve and the outer circumference of the flanges. Because the sealing rings engage with the outer surfaces of the plastic flanges, axial tensile forces exerted on the pipes have no adverse effect on the seal. It is not specified whether the plastic is fiber-reinforced.

[0006] German patent DE 19902456 discloses a method and a plant for the production of centrifugally cast glass fiber tubes with multiple layers of sliced ​​glass fibers. Sliced ​​glass fibers typically have a length between 0.5 and 3 mm. Object of the invention

[0007] It is therefore an objective of the present invention to provide a component that can replace metal components. A further objective is to provide a component with which a good sealing effect can be achieved. Another objective is to provide a component that can be used as a housing or clamp and is preferably used at elevated temperatures. A further objective is to provide a Description

[0008] According to the invention, the aforementioned objectives are achieved by the features of claim 1. Advantageous embodiments are defined in the dependent claims.

[0009] The invention relates to a hollow, in particular circular cylindrical, plastic composite component for use as a preferably self-sealing housing or preferably a self-sealing clamp or coupling in conjunction with one or two components, in particular metal components, to be enclosed by the composite component. The plastic composite component has a shell formed by a wall, on the inside of which two seals are provided spaced apart from each other in the longitudinal direction of the component and preferably at the edge. These seals extend at least partially and preferably circumferentially around the component. In addition, continuous fibers are embedded in the plastic, the majority of which are arranged in the plastic essentially transversely to the longitudinal axis in the circumferential direction of the shell.The circumferentially running continuous fibers should have a fiber length that corresponds at least approximately to the single circumference and preferably to a multiple, i.e., more than ten times the circumference of the component. This has the advantage that the plastic composite component expands only minimally when heated. If the component enclosed by the composite, in particular a metal component, is selected such that it expands more than the composite component when the temperature rises, then a self-reinforcing sealing effect occurs when heated. Such a plastic composite component can therefore ideally replace heavier metal components that cannot function without separate seals.

[0010] From another perspective, a plastic composite component is a tube or ring with a wall comprising at least two layers: a first layer of a fiber fabric or woven material, with a butt joint defined between two ends of the fabric or woven material, and a second layer that is fully bonded to the first layer. The butt joint can be formed between two edges of different fiber fabrics or woven materials in the case of a non-round component, or between the ends of the same fiber fabric or woven material in the case of a round component.

[0011] The fiber fabric or woven fabric is used as a prefabricated semi-finished product.

[0012] In the context of the invention, a prefabricated semi-finished product shall be understood to mean that the fiber fabrics or fiber woven fabrics are cut and / or shaped in such a way that two edges abut each other or are very close to each other, i.e., are separated from each other by a gap of a maximum of 1 mm, preferably less than 0.5 mm or particularly preferably even less.

[0013] Advantageously, the continuous fibers embedded in the plastic can form an outer layer of the wall, to which another plastic layer is injection-molded in an injection molding device. The outer layer containing the continuous fibers is at most half as thick, and preferably at most one-third, and particularly preferably one-quarter as thick, as the total thickness of the wall.

[0014] The continuous fibers are advantageously present as woven or laid fibers, with the fibers being predominantly unidirectionally oriented, essentially in the circumferential direction. This has the advantage that the plastic composite component is very dimensionally stable and expands only minimally with temperature, and certainly less than metal.

[0015] However, it is also conceivable that the semi-finished product is a fiber mat or woven fabric arranged on a carrier material. Alternatively, the fiber mat used can also be held together by a number of weft threads in such a way that it can be cut and handled.

[0016] In terms of manufacturing, the appropriately cut fiber semi-finished product is placed in an injection mold and then overmolded. In the case of fiber semi-finished products embedded in a plastic matrix, the second layer is injection-molded onto the first layer of semi-finished product in an injection molding machine.

[0017] Preferably, the woven or non-woven fabric forms an outer layer of the wall. For manufacturing purposes, a semi-finished product consisting of a woven or non-woven fabric embedded in a plastic matrix, which already has the shape of the final product, is preferably used. This semi-finished product is placed in an injection mold so that the opposing ends are butted together or only a small gap exists between them, and then another layer of plastic is preferably injection-molded onto one side. However, it is also conceivable to overmold the semi-finished product with plastic on both sides.

[0018] To minimize the thermal expansion of the plastic composite component, preferably more than 60%, preferably more than 75%, and particularly preferably more than 90% of the continuous fibers of the non-woven fabric or woven material run in the circumferential direction of the component. In a preferred embodiment, essentially all filaments run in the circumferential direction, meaning that the semi-finished product is preferably wound. This allows the production of plastic composite components that have a lower coefficient of thermal expansion than a metal component to be enclosed by the plastic composite component.

[0019] For the production of the plastic composite component, it is advantageous to use the fiber fabric or woven material preferably as a semi-finished product embedded in a plastic matrix. Such embedded fiber fabrics or woven materials are available on the market as so-called fiber tapes. These are less than 1 mm thick and can be cut to any desired size. A further layer of plastic can then be injection-molded onto one side of the fiber tape, which is placed in an injection mold, using an injection molding device. The plastic matrix of the fiber tape and the plastic to be injected must be compatible and preferably belong to the same group of plastics.

[0020] Advantageously, the fiber content by weight in the plastic matrix used is between 30% and 90%, preferably between 40% and 80% and particularly preferably between 50% and 70%.

[0021] Advantageously, the plastic matrix with the embedded fiber fabric or woven material has a thickness between 0.1 and 1.5 mm, preferably between 0.2 and 1.2 mm, and particularly preferably between 0.4 and 1.0 mm. Preferably, the thickness of the remaining wall is at least approximately the same, preferably at least twice, and particularly preferably at least three times as large as the plastic matrix with the embedded fiber fabric or woven material.

[0022] Preferably, glass, aramid, or carbon fibers are used as continuous fibers, with carbon fibers being particularly preferred. Carbon fibers, in particular, exhibit a very low coefficient of thermal expansion, which makes them ideal for use in plastic composite components.

[0023] According to a preferred embodiment, the seals are injection-molded onto the inside of the component. This has the advantage that they are permanently bonded to the plastic composite component and cannot slip. Advantageously, the seals are accommodated in a groove on the inner wall of the component. This ensures a good bond between the inner wall and the seal. The seals are expediently made of an elastomer. Suitable elastomers include copolyamides, e.g., PEBAX, thermoplastic copolyesters, and urethane- or styrene-based elastomers.

[0024] Advantageously, a plastic from the group consisting of polycarbonates, polyamides, polyphenylene sulfides (PPS), polysulfones, polyethylenes, polybutylene terephthalates or polyetheretherketones is used, with polyamide 6 or polyamide 66 being preferred.

[0025] The subject of this description is a device or component comprising a plastic composite component as described above and one or two inner parts made of metal, wherein the plastic composite component can be placed onto the inner part(s), thereby sealing either a gap between the two inner parts or an intermediate space, in particular annular space, between the inner part and the outer part by means of the spaced-apart seals of the plastic composite component, and the inner part or the intermediate space serves for the passage of a heat transfer medium. This device can be part of a machine or other device used to cool the machine or device.

[0026] Advantageously, the device is a component, in particular a machine part, formed from an inner part and a plastic composite component, wherein the inner part and the plastic composite component define an intermediate space, in particular an annular space, for the passage of a heat transfer medium. This creates a fluid-tight intermediate space between the inner part and the plastic composite component for the passage of a heat transfer medium.

[0027] In an advantageous embodiment, the space is accessible through two openings and interrupted by a bridge or wall such that a heat transfer medium guided into the space through one opening can flow through as much of the space as possible up to the second opening.

[0028] Preferably, the space is interrupted by two openings and by a bridge or wall in such a way that a heat transfer medium introduced into the space through one opening can flow through as much of the space as possible up to the second opening.

[0029] The plastic composite component is advantageously designed to have a lower coefficient of thermal expansion than the metal component it encloses. This creates a self-reinforcing sealing effect when the two components with different coefficients of thermal expansion expand.

[0030] Exemplary embodiments of the invention will now be described in more detail with reference to the following figures. These show: Figure 1: A perspective view of a plastic composite component according to the invention in the shape of a ring; Figure 2: The component of Fig. 1together with a metal tube enclosed by the component in cross-section; Figure 3: A longitudinal section through the arrangement of Fig. 2 along line AA; Figure 4: A detailed enlargement of the Fig. 3 Figure 5: A side view of the component of Fig. 1 ; and Figure 6: A section through the ring wall on a greatly enlarged scale.

[0031] The Figure 1 , 5 and 6Figure 11 shows a plastic composite component 11 according to the invention in the form of a circular cylindrical shell 13, which can be used as a housing. The shell 13 is formed by a wall 15 in which continuous fibers 19 extending circumferentially (arrow 17) are embedded. On the inner surface 21 of the composite component 11, two seals 23, 25 are provided at a distance from each other in the longitudinal direction 22 of the component, projecting from the shell surface. In this case, the seals 23, 25 are provided at the opposite edges of the cylindrical component. The seals 23, 25 preferably consist of an elastomer and are therefore elastically deformable. Two openings 27, 29 are provided in the shell 13, one of which serves as an inlet and the other as an outlet for a heat transfer medium. Fittings 31,33 are molded onto the openings 27,29, to which hoses not shown in the figures can be connected.Between the two openings 27, 29, a radially inwardly projecting web 35 is provided on the inner side 21 of the shell 13. The web 35 extends between the opposing edges 37, 39 of the shell 13 and serves, in conjunction with an inner part, e.g., a tube or inner housing 41, to subdivide an annular space 43 located between the shell 13 and the inner housing 41. Figures 2 to 4 This forces a gaseous or liquid heat transfer medium flowing in through the opening 27 to flow through essentially the entire annular space 43 up to the outlet opening 29. Of course, the web 35 could also be located on the inner housing 41 instead of on the inner side 21 of the jacket 13.

[0032] In Fig. 4A cross-section through the plastic composite component 11 mounted on the inner housing 41 is shown in more detail. It can be seen that the inner housing 41 has a radially outwardly projecting annular rib 45 on one side, onto which an edge section 47 of the plastic composite component 11 is mounted. On the opposite side, the plastic composite component 11 has a second edge section 49, which is formed by an inwardly projecting L-shaped flange 51. Seals 23 and 25 are provided on the inside of the edge sections 47 and 49, sealing the annular space 43 to the outside.

[0033] In Figure 6The structure of wall 15 is shown in more detail. It can be seen that the continuous fibers 19 form a single outer layer, which makes up a maximum of 30%, preferably a maximum of 20%, and particularly preferably a maximum of 15% of the total wall thickness. The seals 23, 25 are injection-molded onto the opposite ends of the component, which is open on both sides.

[0034] Of importance to the invention is that the thermal expansion of the plastic composite component 11 is smaller than that of the inner housing 41. This has the advantage that the sealing effect is further enhanced when the two parts are heated.

[0035] The plastic composite component 11 is manufactured as follows: First, a continuous fiber is preferably wound onto a base body that has the shape of the plastic composite component to be manufactured, and then the shape is fixed with a liquid plastic. Fixing the shape can be achieved by immersing the base body with the wound continuous fiber in a liquid plastic, spraying, or overmolding. It is also conceivable to first coat the continuous fiber with plastic and then subject the finished shape to a heat treatment in which the plastic is remelted. The semi-finished product thus produced is then placed in an injection mold and overmolded with a layer of plastic, or preferably, a plastic layer is injection-molded onto one side. Alternatively, a commercially available fiber tape can be used, which has a fiber layup or woven fabric embedded in a plastic matrix.The fiber tape is cut so that its length corresponds to the circumference and its width to the width of the component. This fiber tape is placed in an injection mold, and then a compatible plastic is injected.

[0036] The invention relates to a hollow plastic composite component for use as a self-sealing housing or self-sealing seal in conjunction with one or two metal components to be enclosed by the composite component. The component consists of a shell formed by a wall, with two seals provided on the inside of the shell. The seals are spaced apart from each other in the longitudinal direction of the component and extend circumferentially. Continuous fibers are embedded in the plastic, the majority of which run substantially transversely to the longitudinal axis in the circumferential direction of the shell. The plastic composite component is characterized by a very low coefficient of thermal expansion. legend

[0037] 11 Plastic composite component 13 Shell 15 Wall 17 Arrow 19 Continuous fibers 21 Inner side 23, 25 Seals 27, 29 Openings 31, 33 Nozzle 35 Web 37, 39 Edges 41 Inner housing 43 Annular space 47, 49 Edge sections of the plastic composite component 51 L-shaped flange

Claims

1. A device having a hollow, in particular circular cylindrical, plastic composite component and one or two inner parts (41) made from metal, wherein the plastic composite component comprises - a casing (13) formed by a wall (15), - two seals (23, 25) which are provided at a distance from one another on the inside (21) of the casing (15) and run in the circumferential direction, as viewed in the longitudinal direction of the component, and - continuous fibres (19) which are embedded in plastic and which are arranged for the most part substantially transversely to the longitudinal axis (22) running in the circumferential direction of the casing (13) in the plastic, and forming an outer layer of the wall (15), onto which a further plastic layer is injection-moulded, characterized in that the plastic composite component can be placed onto the inner part or the inner parts (41) and as a result, either a gap that is present between the two inner parts or an intermediate space (43) that is present between the inner part and the outer part is sealed by the mutually spaced seals (23, 25) of the plastic composite component, and the inner part (41) or the intermediate space (43) is used for channelling of a heat transfer medium.

2. The device according to Claim 1, characterized in that the device is a component formed from an inner part (41) and the plastic composite component (11), in particular a machine part, wherein an at least fluid-tight intermediate space (43) for the channelling of a heat transfer medium is formed between the inner part (41) and the plastic composite component (11).

3. The device according to Claim 1 or 2, characterized in that the intermediate space is accessible by means of two openings and is interrupted by a web or wall such that a heat transfer medium that is conducted through an opening into the intermediate space can flow to the greatest extent possible through the entire intermediate space as far as the second opening.

4. The device according to any one of Claims 1 to 3, characterized in that the plastic composite component and the inner part (41) are configured such that the plastic composite component has a smaller thermal coefficient of expansion than the metal component (41) surrounded by the plastic composite component.

5. The device according to any one of Claims 1 to 4, characterized in that the layer with the continuous fibres is used either as a fibre woven fabric or fibre fabric.

6. The device according to any one of Claims 1 to 5, characterized in that the layer with the continuous fibres of the plastic composite component is used as a wound semi-finished product.

7. The device according to any one of Claims 1 to 6, characterized in that in the plastic composite component, more than 60%, preferably more than 75% and particularly preferably more than 90% of the continuous fibres run in the circumferential direction of the component.

8. The device according to any one of Claims 1 to 7, characterized in that to produce the plastic composite component, the fibre fabric or fibre woven fabric is used as semi-finished product, embedded in a plastic matrix, onto which plastic matrix a further plastic layer is injection-moulded in an injection moulding device.

9. The device according to any one of Claims 6 to 8, characterized in that the fibre proportion in terms of weight in the plastic matrix used is between 30% and 90%, preferably between 40% and 80% and particularly preferably between 50% and 70%.

10. The device according to any one of Claims 1 to 9, characterized in that glass, aramid or carbon fibres are used as fibres, wherein carbon fibres are preferred.

11. The device according to any one of Claims 1 to 10, characterized in that the plastic matrix in the plastic composite component with the fibre fabric or fibre woven fabric embedded therein has a thickness between 0.1 and 1.5 mm, preferably between 0.2 and 1.2 mm and particularly preferably between 0.4 and 1.0 mm.

12. The device according to any one of Claims 1 to 11, characterized in that the seals (23, 25) in the plastic composite component are injection moulded from an elastomeric material on the inner side (21) of the component and preferably accommodated in a groove on the inner side (21) of the wall (15).

13. The device according to any one of Claims 1 to 12, characterized in that a plastic from the group either of the polycarbonates, polyamides, polyphenyl sulphides (PPS), polysulphones, polyethylenes, polybutylene terephthalates, polyether ether ketone, polyamide 6 or polyamide 66 is used.