EP4376688A1

EP4376688A1 - Flexible hose, in particular a vacuum cleaner hose, and method for producing same

Info

Publication number: EP4376688A1
Application number: EP22748386.4A
Authority: EP
Inventors: Ingo STEITZ; Sascha Gärtner; Marco Holst
Original assignee: Truplast Kunststofftechnik GmbH
Current assignee: Truplast Kunststofftechnik GmbH
Priority date: 2021-07-29
Filing date: 2022-07-29
Publication date: 2024-06-05
Also published as: CN117241716A; DE102021003907A1; WO2023007001A1

Abstract

The invention relates to a flexible hose (10), in particular a vacuum cleaner hose, comprising a corrugated-profile inner hose (12) which delimits, by means of an inner face, a cavity for conveying media along a longitudinal axis (18), is surrounded, on an outer face (20), by a substantially flat covering (22), and is provided, on at least one of its two ends, with a connection piece. An electrical conductor (30) is situated radially between the inner hose and the covering, which conductor extends from one end to the other end of the inner hose and terminates in the connection piece to provide electrical contact. The electrical conductor is formed by a resilient flat-conductor assembly (32) which extends along the hose in an electrically insulated manner in parallel with the longitudinal axis and is held on the corrugated profile (34) of the inner hose at least by the covering, as a result of which in particular hoses which are long, equipped with electrical conductors and have a low weight can be produced cost-effectively. The invention also relates to a method for producing such a hose on a large scale.

Description

FLEXIBLE HOSE , PARTICULARLY VACUUM CLEANER HOSE , AND PROCESS FOR PRODUCTION THEREOF

TECHNICAL AREA

The present invention relates to a flexible hose according to the preamble of claim 1. In particular, the invention relates to a flexible vacuum cleaner hose with one or more electrical conductors, as is used in large numbers in an industrial environment, in trade and in private households comes, and its production.

BACKGROUND OF THE INVENTION AND PRIOR ART

Vacuum cleaner hoses with integrated electrical conductors are used, for example, to electrically connect vacuum cleaners with motor-driven attachments for cleaning purposes, such as roller brushes. In the area of so-called power tools, the power supply for an electric tool, such as a hand-held grinding machine, can also be provided via the suction hose for extracting the dust and grinding particles.

Another area of application for suction hoses with integrated electrical conductors are so-called central vacuum cleaners: In order to be able to conveniently switch the central vacuum cleaner on and off in another room, two electrical conductors are routed in or along a hose profile of the suction hose. These conductors are routed via a switch located in a handle of the suction hose. In a connection piece on the end of the suction hose facing away from the handle, the ends of the two electrical conductors make contact with two metal contact plates, which are connected to the central Vacuum cleaners are further connected. By activating the switch on the handle of the suction hose, the contact is closed or opened and the central vacuum cleaner is switched on or off.

In the prior art, there is no lack of suggestions as to how electric conductors can be laid in or on a flexible vacuum cleaner hose. For example, it is known from the publications EP 0884 019 Bl and DE 29804 962 Ul to glue an inner hose to the inner wall of the suction hose, which inner hose forms a protective cover for cable routing there.

Gluing or gluing the inner hose to the inner wall of the suction hose using hot glue, for example, only works with relatively short hose lengths. With greater hose lengths, the reliability of the bond decreases because the hot-melt adhesive cools down too much when the inner hose with the hot-melt adhesive is inserted into the suction hose, forming a skin on the surface and no longer with the adhesive partner, i.e. the inner wall of the suction hose merges.

For relatively long vacuum cleaner hoses, such as those usually used in central vacuum cleaners, it is therefore necessary to couple individual hose sections of, for example, 2.5 m in length with sleeves, as are known, for example, from publication EP 1262 704 B1. The associated expense, as well as the fact that such vacuum cleaner hoses are less flexible in one direction than in other directions due to the glued-in inner hose, is undesirable for some applications.

It has also been proposed to run electrical conductors along the outside of a flexible vacuum cleaner hose and, for example, to fix them as holders via a number of clips, loops, straps or straps located on the hose at intervals. A such a suction hose can be found, for example, in publication DE 10 2013 020 687 A1. A disadvantage of this prior art can be seen in the fact that the electrical conductor or conductors form loops between the holders when the suction hose is bent and can interfere with the user's work.

As an alternative to this, it is known from publication EP 2614 762 A2 to attach a supply line, in particular a power cable with three individual conductors each with a line cross-section of 2.5 mm ² , to the outside of a suction hose, with the supply line and the suction hose being loose from an outer hose are surrounded. In addition, it is disclosed here that the supply line can be wound spirally around the suction hose at least once, preferably with three or four turns, in order to achieve greater length variability. In the publication WO 2019/011591 A1 (FIG. 4) it is also proposed to use a reinforcing body in the form of a wire spiral provided in a dust removal hose body of a suction hose for a vacuum cleaner as an electrically conductive component.

It is also known - see for example the publication DE 9114 487 U1 - to lay electrical cables freely within a suction hose. This structure has been proposed primarily for the extraction of dust during processing, e.g. by grinding. However, the electric cable forms a flow obstacle and can, especially with the long hoses for central vacuum cleaners, promote clogging with the dirt that is common in the household, such as hair or fibers. Such blockages are difficult to remove with the long hoses.

Furthermore, document EP 1656 873 A2, which forms the preamble of patent claim 1, discloses a vacuum cleaner hose with a plurality of outwardly open, helical threads and laterally delimited by ribs grooves for receiving electrical conductors shear, which open starting from the groove bottom without constriction to the outside, and with a covering, braided hose covering the grooves and the electrical conductors inserted therein.

In this known vacuum cleaner hose, the braiding of the hose cover, seen in a longitudinal section, thus covers the corrugated profile of an inner hose formed by the grooves with the electrical conductors accommodated therein. As a result, the vacuum cleaner hose has a smoothed outer peripheral surface. In comparison to conventional hoses without a hose casing, this results in better sliding behavior. During suction operation, the vacuum cleaner hose does not get caught on the edges of the body while sliding over wall corners, furniture, door, workpiece or body edges. This reduces the effort required in suction operation, avoids jerky interruptions in the movement of the operator during suction operation caused by snagging, reduces noise and, last but not least, protects the edges of the body - all in all, desirable effects, especially for hose use with central vacuum cleaners, which in some cases also in the publication WO 2019/011591 A1 on the hose casing disclosed there made of a textile mesh.

A disadvantage of this prior art, however, can be seen in the fact that compared to the solutions described above for laying electrical conductors in or on flexible vacuum cleaner hoses, the generic vacuum cleaner hose has a relatively high weight due to its helical routing of the electrical conductors, which is particularly important in the case of long Vacuum cleaner hoses, such as those used on central vacuum cleaners, is not desirable. In this context, it is also found in the prior art according to the document DE 1218 032 A to be disadvantageous in terms of costs, weight and electrical voltage drop to arrange an electrical line sinusoidally corrugated or spirally on an elastic hose. Instead, a vacuum cleaner hose is proposed here, in which an electric expansion cable is fixed to a tubular elastic body while extending parallel to a center line of the body, the electric expansion cable being fixed in a stretched state to the tubular body in close succession , so that the electrical expansion cable can compress or stretch between the attachment points.

More precisely, the vacuum cleaner hose disclosed in document DE 1218 032 A comprises a tubular body made of a fabric impregnated with rubber, for example. 1 to 4 of this publication, the following is said for the manufacture and further construction, in particular for the “electrical equipment” of this vacuum cleaner hose: A reinforcing wire spiral, for example made of steel, is arranged inside the tubular body. A cord, for example of jute, is wound around the tubular body so that the turns of the cord lie between the turns of the spiral. Before the cord is wrapped around the tubular body, an electrical strain gauge cable is applied to the body so that it extends in a straight line approximately parallel to the centerline of the body. Before the cord is wound up, the electrical expansion cable is stretched. The cord is used to attach the expansion cable to the tubular body at the points where the expansion cable is held between the tubular body and a turn of the cord. Then the tubular body is provided with a braided sheath. The ends of the expansion cord are brought out of the sheath. A plug can be attached to a attached to the end of the cable. The other end of the electrical extension cord's can be connected to a socket who is fastened to one end of the hose by means of a clamp.

Unlike the vacuum cleaner hose disclosed in the generic prior art according to the document EP 1656 873 A2, the vacuum cleaner hose according to the document DE 1218 032 A does not have an inner hose with a wavy profile. Rather, the tubular body is forced into shape between the internally supporting wire spiral and the cord tying it in from the outside, which at the same time serves to fix the electrical expansion cable at defined, spaced-apart points on the tubular body. Such a construction with a plurality of components is not only complex in relation to production, but also still has a relatively high weight, leading to a certain "bulkyness" of the vacuum cleaner hose, which is undesirable for certain applications, as a result of the integrated wire spiral and poor recyclability.

With regard to the electrical expansion cable of the vacuum cleaner hose according to the publication DE 1218 032 A, it should also be noted that there is shown a thick, two-wire power line in relation to the wall thickness of the hose or the braiding, similar to a loudspeaker cable, which is separated from the rest of the vacuum cleaner hose under the braiding protrudes unsightly or leads to an elongated bulge on the circumference of the hose (cf. FIGS. 3 and 4 of this publication). This bulge can prevent the hose from moving if, for example, it is pulled over an edge or is supposed to roll around its longitudinal axis. According to the description, such expansion cables can be extended by at least 200 percent of the original length. However, technical details on these particularly stretchy cables are not described here. A further disadvantage of this prior art is seen ge in the fact that the electric expansion cable must be stretched significantly, ie by at least 33% of the normal length in the application described, before it is attached to the tubular body by means of the cord in order not to get between the attachment points only to be lengthenable, but also to be compressible. This is not only expensive to produce, but can also result in the finished vacuum cleaner hose always having a certain pre-stretching or pre-curvature in the unloaded state, which can be undesirable, for example, in the specific application of a central vacuum cleaner. In the previously known embodiment, this can of course be counteracted within certain limits by making the central reinforcement spiral stronger, which, however, is detrimental to the flexibility of the vacuum cleaner hose.

Finally, a data communication cable and a method for producing such a cable are known from publication WO 2020/139199 A1. This data communication cable comprises a set of elongate bodies, each formed of an elastic material and having an unstretched free length, and for each of the elongate bodies, a set of conductive wires arranged along the elongate body such that each conductive wire extends to more than the free length of the elongate body is extensible. At least one conductive wire is configured to communicate data between electronic devices. Furthermore, the conductive wires are extendable in response to an elongation of the elongate body, so that the extended data communication cable remains usable for data communication between the electronic devices.

In a specific embodiment of this Datenkommuni cation cable, the conductive wires are sinusoidal, wave or arranged in a serpentine manner along the respective elongate body. Any use of such data communication cables in connection with flexible vacuum cleaner hoses is not disclosed in this prior art.

TASK

Compared to the state of the art described, the invention is based on the task of designing a flexible hose, in particular a vacuum cleaner hose, with an inner hose, a covering and at least one electrical conductor in such a way that the problems mentioned above with regard to the state of the art are addressed and in particular, long "electrified" hoses with a comparatively low weight and the above-mentioned operating properties, which are desirable for use in central vacuum cleaners, can be produced inexpensively. The object of the invention also includes the specification of a method for producing such a flexible hose provided with at least one electrical conductor, which enables the simplest, quickest and cheapest possible production or partial assembly of the hose with the at least one electrical conductor in large numbers.

PRESENTATION OF THE INVENTION

These objects are achieved by a flexible hose, in particular a vacuum cleaner hose, with the features of patent claim 1 and a method for producing a flexible hose with the method steps of patent claim 11. Before some embodiments of the invention are the subject of dependent claims.

In the case of a flexible hose, in particular a vacuum cleaner hose, which has an inner hose with a corrugated profile - i.e. correspondingly preformed - which delimits a cavity for conveying media along a longitudinal axis of the hose with an inner side, on an outer side by a substantially smooth casing surrounded and at least one of its two ends with a connector is provided, wherein an electrical conductor is arranged radially between the inner tube and the sheath, which extends from one end to the other end of the inner tube and ends in the connector for electrical contact mediation; According to the invention, the electrical conductor is formed by an elastic flat conductor arrangement, ie in this context against - albeit small - restoring forces that can be stretched and compressed, which extends parallel to the longitudinal axis along the hose essentially without preload and is electrically insulated and on the wavy profile of the inner tube is held by the sheath.

In other words, the electrical conductor is - unlike in the generic prior art - not wound around the inner tube or laid primarily in the circumferential direction of the inner tube. Rather, the electrical conductor extends essentially without pretension directly in the longitudinal direction of the hose according to the invention, parallel to the longitudinal axis along the hose. As a result, the electrical conductor is significantly shorter compared to the prior art described at the outset, which is associated with a correspondingly lower weight and lower cost of the hose.

Due to the design of the electrical conductor as "elastic"

- In contrast to (essentially) "rigid" - flat conductor arrangement, there is also no need for the electrical conductor, seen in the longitudinal section of the flexible hose, to follow the wavy profiling of the inner hose in the course of the waves. Rather, the elastic flat conductor arrangement can bridge the depressions of the wavy profile on the outside of the inner tube, while it rests on the elevations of the wavy profile. Nevertheless, due to its elastic properties, the flat conductor arrangement is able to follow bends and/or elongations of the flexible hose without offering any significant resistance. The elastic flat conductor arrangement is stretched or compressed between the elevations of the wavy profile of the inner hose, for example depending on the bending direction. The same applies to pressure or tension in the longitudinal direction of the hose. Since the elastic flat conductor arrangement is inserted between the inner tube and the sheathing essentially without any prestressing, the hose is advantageously free from constraining forces caused by the elastic flat conductor arrangement, which would give the hose a prestressing or precurvature.

Advantageously - in addition to the advantages of coated hoses already mentioned - the coating of the hose also serves according to the invention to hold the elastic flat conductor arrangement on the inner hose, more precisely on its corrugated profile on the outside of the inner hose. However, depending on the materials used, this should not rule out the possibility of an additional adhesive or the like between the elastic flat conductor arrangement and the outside of the inner tube and/or an inside of the sheathing. can be used, which of course must not noticeably hinder the elasticity of the flat conductor arrangement.

In this case, the electrical conductor, as a result of its design as an elastic flat conductor arrangement, is also not excessively "thick", so it does not lead to a greater local increase in the diameter of the sheathed hose. The word component "flat" in the term "flat conductor arrangement" thus speaks in fact to an embodiment of the conductor arrangement in which the length and width extensions of the conductor arrangement are significantly greater than their thickness extension. While the length of the conductor arrangement results directly from the desired total length of the flexible hose, a "significantly greater width extent compared to the thickness extension" in the elastic flat conductor arrangement according to the invention means a lower thickness with respect to right to the longitudinal axis of the hose at least a factor of 10 greater width along the circumference of the hose. In a preferred exemplary embodiment of the hose according to the invention, the ratio of width to thickness of the elastic flat conductor arrangement is approximately in a range between 15:1 and 40:1, more preferably between 20:1 and 30:1.

In addition, since the flexible flat conductor assembly is attached to the outside of the inner tube and not somehow integrated into the inner tube, it is advantageously relatively easy to remove the flexible flat conductor assembly of a hose to be disposed of from the remainder of the hose for recycling purposes.

Last but not least, the design of the flexible hose according to the invention advantageously allows (at least) a 2-step procedure in its production, in which the inner hose is first produced with its wavy profile on the outside, before this “basic hose” is only passed through in a second step Application and attachment of the elastic flat conductor arrangement is "refined" with regard to the desired electrical properties of the hose. As a result of this modular construction of the hose, it is therefore possible, please include hoses with different elastic flat conductor arrangements, which differ, for example, in the number of installed individual conductors (about 1, 2, 3 or 4 individual conductors) and/or according to the requirements transmitted services in the respective effective cable cross-section can be manufactured from a type of modular system, which ensures a high level of flexibility in hose production and also offers cost advantages.

Preferably, the elastic flat conductor arrangement is held on the wavy profile of the inner hose - if necessary alone - by the elastic flat conductor arrangement being tion is pressed by means of the sheathing on elevations of the wavy profile. Viewed in the radial direction with respect to the longitudinal axis of the hose, there is thus a form fit for the elastic flat conductor arrangement “sandwiched” or inserted between the inner hose and the sheathing, which prevents a radial movement of the elastic flat conductor arrangement.

On the other hand, in a direction along the longitudinal axis of the hose or transversely to it, i.e. viewed in the circumferential direction of the hose, there is a frictional connection for the elastic flat conductor arrangement, which prevents a longitudinal or transverse displacement of the elastic flat conductor arrangement over the inner hose or under the sheathing. Between the individual contact points of the elastic flat conductor arrangement to the inner hose, namely at its elevations or to the sheathing, the flat conductor arrangement can then lengthen or compress due to its elastically deformable design in accordance with an axial deformation and/or a bend of the hose, as already done mentioned. For this purpose, the elastic flat conductor arrangement can have an elastic stretching capacity of between 25% and 75%, e.g. 50% in a specific application in the longitudinal direction, depending on the application.

To increase the force or frictional connection between the elastic flat conductor arrangement and the inner hose or the sheathing of the hose, the elastic flat conductor arrangement or at least part of it can also be provided with a rubber coating, which can be done with little effort. If the elastic flat conductor arrangement comprises, for example, a knitted or braided fabric, such a (partial) rubber coating can be formed, for example, by incorporating or braiding a rubberized thread. In principle, it is conceivable that the essentially smooth casing of the hose consists of one or more elastic bands, which are wound elastically around the inner hose, which already has a wavy profile, with the elastic flat conductor arrangement under the band/bands. Also, the sheathing in a circular knitting machine from, for example, textured polyamide threads or the like. be knitted circularly around the inner tube with the elastic flat conductor arrangement thereon.

In contrast, however, an embodiment of the hose is preferred in which the sheathing is formed by braiding the inner hose from monofilament and/or multifilament plastic threads. Such braiding advantageously offers a firm mechanical hold for the elastic flat conductor arrangement, but still allows a slight expansion of the sheathing, for example during the final assembly of the hose at the ends of the elastic flat conductor arrangement with pliers or the like. to be able to attack, so that the elastic flat conductor arrangement can be pulled slightly out of its position between the inner tube and the sheathing for making contact in the connector. If, in connection with the present invention, a sheathing of the inner hose is mentioned, hoses braided with round monofilaments, flat monofilaments, plied monofilaments and/or multifilaments are primarily addressed, with the monofilament or multifilament threads of the braiding possibly even being covered with short fibers can be flocked from a ther moplastic plastic, as disclosed in the publication EP 2363 210 A2.

The braiding of the inner tube with monofilament and/or multifilament plastic threads serves here not only preferably as a vehicle for holding the elastic flat conductor arrangement on the wavy profile of the inner tube. Because of the supportive effect of the braid, braided hoses are also better than conventional hoses mechanical properties. For example, a braided hose will buckle later than a conventional hose. If the hose is not braided too tightly, it is more flexible than a conventional hose because it can be bent and twisted more easily until it buckles. In addition, in terms of improved appearance, braided hoses offer the possibility of a more flexible outer appearance compared to conventional hoses.

So that the flexibility of the hose is improved by the supporting braid and not worsened, it is necessary that the braid is (still) applied loosely to the hose and is not braided as tightly as possible. As a result, the braiding can be compressed while the hose is being bent until the edges of the threads running parallel to one another butt against one another. Only then is a significant counterforce built up, which counteracts the bending movement. For example, if the braiding is too tight and tightly braided, the braided hose no longer has much better flexibility than the standard hose, and can even be more rigid.

The braiding must therefore not be applied too tautly and tightly to the hose and/or compressed too much on the hose. The properties of the braiding vary depending on whether monofilaments, multifilaments or both threads are braided in a mixture. In the case of a hose that is only loosely braided with monofilaments, i.e. relatively thick individual fibers, there are inevitably gaps in the braiding. A maximum coverage of the hose circumference of approx. 80% can be achieved here. If a hose braided in this way is bent, the threads of the braid sliding on one another and thus also the overlapping gaps are displaced, although this is also suitable braided to keep the elastic flat conductor arrangement on the wavy profile of the inner tube.

With a braid made of stretchable and compressible multifilaments, i.e. fiber bundles or a hybrid braid made of monofilaments and multifilaments - which is also well suited for fixing the elastic flat conductor arrangement on the inner hose - the circumference of the hose can be braided completely covered, so that a fabric-like surface is created. Because of the stretchable multifilaments, such braids attach to the outer radius of the bent hose when the hose is bent and compress to the inner radius of the bent hose without forming gaps. Here, too, excessive compression of the braiding on the hose leads to possibly undesired stiffening or bulging of the hose. A person skilled in the art should take all of this into account when attaching the elastic flat conductor arrangement to the wavy profile of the inner hose with the aid of a braid.

In a preferred embodiment of the flexible hose, it can also be provided that the elastic flat conductor arrangement has at least one stranded cable which, viewed in the longitudinal direction of the flat conductor arrangement, runs in a serpentine or zigzag shape and is held in place by threads, which are similar to a Form the knitted fabric around the stranded line thread loops that are intertwined to form stitches. Due to the serpentine or zigzag course of the stranded line, which as such has only a low elastic stretching capacity in the axial direction, the elastic flat conductor arrangement has good stretchability. The serpentine or zigzag shape of the stranded cable is stretched or compressed in its wavy or triangular shape, depending on whether the elastic flat conductor arrangement is subjected to tension or compression in the axial direction. Meanwhile, those at Ma- see intertwined threads, which extend around the stranded wire or enclose it, for the necessary cohesion in the elastic flat conductor arrangement.

If the flexible hose with a "minimum electrical equipment" only has an elastic flat conductor arrangement with only one stranded cable, it is conceivable, for example, to use the hose in an environment in which the electrical conductor of the hose provides - possibly additional - grounding of an electrical attachment or power tools towards a vacuum cleaner. In most cases, however, the flat conductor arrangement will have two or more stranded lines (e.g. three or four stranded lines) in order, as mentioned above, to be able to be used for the electrical supply of an additional device or power tool and/or switching functions, in accordance with the electrical requirements of the respective application.

Particularly with regard to the narrowest possible configuration of the elastic flat conductor arrangement, it is preferred in such a case if the elastic flat conductor arrangement has at least two stranded cables which, seen transversely to the flat conductor arrangement, run in a serpentine or zigzag shape at an axial distance from one another. In this way, the individual stranded cables can be arranged at a close distance from one another, with snake or zigzag shapes that are "parallel" to one another, without the stranded cables touching or impeding one another when their respective wave or triangle shape is stretched or compressed.

Furthermore, the or each stranded wire of the elastic flat conductor arrangement can preferably have a plurality of metallic individual wires and at least one plastic thread for strain relief. It is thus possible in a simple manner to reinforce the respective stranded line or to reinforce it against tearing. In principle, it is possible to insulate the entire elastic flat conductor arrangement so that it extends parallel to the longitudinal axis of the hose in an electrically insulated manner, for example by encapsulating the entire arrangement in an electrically insulating, elastically deformable plastic foam. In contrast, however, it is preferred, particularly with regard to low weight and the smallest possible installation space requirement, if the at least one stranded cable of the elastic flat conductor arrangement is provided with extruded insulation or is enamelled. In this way it is also possible to achieve greater elongation of the overall arrangement.

In a preferred embodiment of the hose, the threads of the knitted fabric of the flat conductor arrangement can also be at least partially elastic, wherein the threads of the knitted fabric can comprise, for example, a mixture of polyester or polyamide fibers with elastane fibers. With very good availability, these fibers have high heat resistance and are advantageously flame retardant. In principle, however, it is also imaginable to bring about the cohesion of the individual components in the elastic's flat conductor arrangement by means of a knitted fabric from relatively rigid threads that are intertwined with it somewhat looser or looser meshes, so that the necessary deformation work by the individual Thread loops of the Ge can be made active.

It is also preferred if the connecting piece has a contact area to which the elastic flat conductor arrangement is electrically connected, with the contact area being able to have at least one slip ring in particular. For example, in a central vacuum cleaner, the twistability of the hose with respect to a stationary, electrified connection socket with the (the) slip ring (s) associated, spring-loaded contact pins or a connection of such Hose can be easily guaranteed without angle of rotation orientation of the connector to the junction box. It is obvious to a person skilled in the art that a mobile vacuum cleaner and/or a terminal device can also be provided with such a connection socket. The elastic flat conductor arrangement can, of course, also be attached to one end of the hose in a handle or the like. end with a switch over which the electrical conductor is looped, depending on the intended use of the "electrified", flexible hose suitable for this purpose.

In terms of method, the present invention provides a method for producing a flexible hose, which comprises at least the following three method steps a) to c): a) Forming an inner hose, which delimits a cavity with an inside around a longitudinal axis and at least one on an outside Has profiling, seen in section has a waveform with elevations and depressions; b) application of an elastic flat conductor arrangement to the outside of the inner tube, essentially without pretension, so that the elastic flat conductor arrangement runs along the longitudinal axis and transversely to the elevations and depressions of the profiling; and c) attaching the elastic flat conductor arrangement to the outside of the inner tube by attaching a sheath to the wavy profile.

An important aspect here is the separation of the procedural steps a) forming the inner tube on the one hand and b) applying and c) fastening the elastic flat conductor arrangement on the outside of the inner tube on the other hand. This separation of the process steps initially offers the advantage that, in the manner of a modular system, an inner tube of the same basic type can be further refined according to the respective electrical line requirements by applying/fastening the elastic flat conductor arrangement, or not if this is not necessary or desired. It is also possible to have an inner tube of the same basic type by applying/attaching different elastic flat conductors, which differ, for example, in the number and/or the line cross-section of the individual conductors, their dimensions and/or their elasticity, the respective requirements or wishes to be further equipped with electricity in a targeted manner accordingly.

This separation of process steps a) on the one hand and b) or c) on the other hand also leads to recycling advantages, because the elastic flat conductor arrangement subsequently applied/attached to the outside of the inner hose can generally be removed more easily when the hose is disposed of than a conductor, which is an integral part of the inner tube or is accommodated in the inner tube.

Due to the fact that, according to method step b), the elastic flat conductor arrangement is applied along the longitudinal axis and transversely to the elevations and depressions of the wavy profiling on the outside of the inner tube essentially free of prestress - in this respect, exactly the opposite of the procedure in the generic prior art, where the conductors are laid transversely to the longitudinal axis and along the Profilver depressions - all that is required is a simple axial relative movement between the inner tube and the elastic flat conductor arrangement during the application of the elastic flat conductor arrangement. The application of the elastic flat conductor arrangement can thus be carried out as quickly as possible for a predetermined hose length with a minimum use of conductor material. Time-consuming winding of long and correspondingly heavy conductors around the longitudinal axis of the inner hose is no longer necessary.

Process step c) is also part of a fast and cost-efficient production of a flexible (electrical) hose conducive to mass production. Because in a common process step, the elastic flat conductor arrangement is fixed to/on the wavy profile of the inner hose and the flexible hose is provided with a sheathing on the outside of the inner hose.

In principle, the inner hose can be formed, for example, by blow molding a suitable plastic material, with the wavy profile on the outside of the inner hose being able to result from a corresponding grooved or grooved design of the mold parts or halves of the blow mold. In contrast, it is preferred if, in step a) of forming the inner tube, a profile is first extruded from a plastic material, whereupon the profile is wound helically to form the inner tube - single-thread or multi-thread, according to the respective specifications - with adjacent turns of the profile be connected to each other in a media-tight manner. The advantages of such a wound inner tube compared to a blow-molded inner tube are, in particular, that the inner tube can be designed with an essentially smooth inner surface and accordingly low flow losses and only low noise development during operation and as a result of good dimensional stability and resilience of the inner tube higher suction power can also be achieved.

The adjacent windings of the profile are preferably connected to one another in a media-tight manner by means of a hot-melt adhesive. This ensures process-reliable, fast and cost-effective production of the inner tube. However, other connection options, possibly using other adhesives, or for example the production of a material connection between the individual profile windings by means of laser welding or the like, are also conceivable. Steps b) of applying and c) of (finally) attaching the elastic flat conductor arrangement to the outside of the inner tube by attaching the sheathing to the wavy profile of the inner tube can in principle be carried out one after the other, especially if when applying the elastic Flat conductor arrangement already a (pre) fixing to the elevations of the profiling with the aid of an adhesive (eg glue or adhesive tape) it follows. On the other hand, it is preferable, especially with regard to the fastest and most efficient production possible, if steps b) of applying and c) of fastening the elastic flat conductor arrangement on the outside of the inner tube are carried out simultaneously.

Finally, in a specific embodiment of the method for manufacturing this flexible tube that is preferred with regard to the above-described physical embodiment of the flexible tube, the wavy profile of the inner tube can be braided around with monofilament and/or multifilament plastic threads to form the sheathing, with the elastic flat conductor arrangement being essentially is applied to the outside of the inner tube without pretension at the braiding point, so that after the braiding point the braided plastic threads press the elastic flat conductor arrangement against the elevations of the wavy profile of the inner tube. The elastic flat conductor arrangement can be supplied in a simple manner, for example, from a spool or roll which has a core onto which the elastic flat conductor arrangement is wound.

Further features, properties and advantages of the flexible hose according to the invention and the method for its manufacture are apparent to those skilled in the art from the following description of a preferred exemplary embodiment. BRIEF DESCRIPTION OF THE DRAWINGS

The invention is explained in more detail below using a preferred exemplary embodiment with reference to the attached, partially schematic drawings, in which identical or corresponding parts or sections are provided with the same reference symbols. In the drawings show:

1 shows a simply interrupted plan view of a flexible hose according to the invention, namely a vacuum cleaner hose, which is provided with a connection piece on both sides and in between has a sheathing in the form of a braiding of an inner hose—illustrated in detail in FIG. 1;

FIG. 2 is a single-broken longitudinal sectional view of the flexible hose of FIG. 1;

3 is an enlarged representation of detail III in FIG. 2 in a central region of the flexible hose according to FIG.

4 is a sectional view of the flexible hose according to FIG

Fig. 1 according to the section line IV-IV in Fig. 1;

5 shows a side view broken off four times of the flexible hose according to FIG. 1 in a state bent in an S-shape, with the casing being shown broken away, in order to illustrate how the elastic flat conductor arrangement is able to follow an elastic deformation of the inner hose; 6 is a top and bottom plan view broken away of the flexible hose of FIG. 1 looking in the direction of arrow VI in FIG. 5, with the sheath shown broken away to illustrate how the flexible conductor array along an outer curve of the inner tube ge is stretched;

Fig. 7 is a plan view broken off upwards and downwards of the flexible hose according to FIG. 1 looking in the direction of arrow VII in FIG inner tube is compressed;

8 is a plan view broken off on both sides of the flexible hose according to FIG is bent;

9 shows a perspective view broken off to the left of the flexible hose according to FIG. 1, obliquely from above/to the left, with a view of the connection piece of the hose at its end on the right in FIG. 9; and

10 shows a perspective exploded view of the flexible hose according to FIG. 1, broken off to the left, from diagonally above/to the left, in particular to illustrate how the elastic flat conductor arrangement is electrically connected to contact areas in the connection piece. DETAILED DESCRIPTION OF THE EMBODIMENT

In the figures, a vacuum cleaner hose is generally numbered with the reference numeral 10 as an example of a flexible hose. The hose 10 has an inner hose 12 which is profiled in a corrugated manner, i.e. correspondingly pre-profiled, and which, with an inner side 14, delimits a cavity 16 for conveying media along a longitudinal axis 18 of the hose 10. On an outer side 20, the hose 10 is surrounded by an essentially smooth casing 22, which in the exemplary embodiment shown is a braid made of monofilament and/or multifilament plastic threads. 1 and 2, the hose 10 is also at least one of its two ends 24, 26 - provided with a connecting piece 28, which is approximately for example designed as a plug-in connection in the illustrated Ausfüh - here at both ends 24, 26.

As will be described in detail below, an electrical conductor 30 is arranged radially between the inner tube 12 and the casing 22, which extends from one end 24 to the other end 26 of the inner tube 12 and ends in the connection piece 28 for establishing electrical contact, such as 10 shows. According to essential features of the hose 10, the electrical conductor 30 is formed by an elastic cal flat conductor arrangement 32, which extends parallel to the longitudinal axis 18 along the hose 10 essentially without pretension and electrically insulated. In this position, the elastic flat conductor arrangement 32 is held at least by the casing 22 on the wavy profiling 34 of the inner hose 12 .

Are shown in Figs. 1 and 2, only the hose areas near the ends 24, 26 of the hose 10, which can be several meters long depending on the application. With central vacuum cleaners, for example, hose lengths are between 6 and 15 meters quite common. In the exemplary embodiment shown, the connecting pieces 28 at the two ends 24, 26 of the hose 10 are designed identically as plug-in connections. Other end pieces - e.g. a handle with one (or more) switch(es) on one side and a plug connection on the other side or a combination of plug connection here and junction box there, etc. - are of course also conceivable here, depending on the respective mission requirements.

The wavy profile 34 of the inner tube 12 is shown in section along the longitudinal axis 18 of the tube 10 in Figs.

2 and 3 to see. Accordingly, the profiling 34 has, seen in section, a wave shape with alternating elevations 36 or wave crests and depressions 38 or wave troughs on the outside. In the illustrated embodiment, the elevations 36 and depressions 38 seen in the circumferential direction of the inner tube 12 single-thread - or alternatively multi-th gig, not shown here - helically. This can be explained by the fact that it is a wound inner hose 12, i.e. an inner hose 12 whose wall is formed from a profile 39 wound helically around the longitudinal axis 18, with adjacent turns of the profile 39 being connected to one another in a media-tight manner.

The profile 39 of the inner hose 12 shown here by way of example has two areas when viewed in cross section, namely one in Fig.

3 on the right, the cross section of which essentially has the shape of the letter U in "angular" notation and which forms the outer recesses 38 of the profiling 34 on the wound inner tube 12, and an area on the left in Fig. 3, which is viewed in cross section essentially has the shape of a lying or 90 ° clockwise tilted letter C and the coiled inner tube 12, the outer elevations 36 of the profile 34 bil det. As can be clearly seen in Fig. 3, the C-shaped rich a turn of the profile 39 quasi "hooked" over the right leg of the U-shaped area of an adjacent turn of the profile 39 so that there is a short Pro filüberlappung along the longitudinal axis 18 results. In the region of this profile overlap, a hot-melt adhesive 40, for example, is provided for media-tight connection of the adjacent windings of the profile 39, which forms a helical circumferential seam.

On the inside 14 of the inner hose 12, the U-shaped areas of the profile 39 form a substantially smooth inner surface 42 of the hose 10, which is only interrupted by a narrow spiral groove 44 formed between the individual turns of the profile 39, as best shown in 3 can be seen.

In the exemplary embodiment shown, the profile 39 of the inner tube 12 is extruded from a plastic material such as polyethylene (PE), polypropylene (PP) or an ethylene-vinyl acetate copolymer (EVAC). As for the hot melt adhesive 40, it can also be made of a plastic material such as PE or EVAC.

As the detail below in FIG such as polyamide (PA) or PE. When the hose 10 is bent, the multifilament threads lie flat against the inner hose 12 on the tension side and compress on the pressure side of the inner hose 12 transversely to the thread and thus also towards the wall of the inner hose 12, so that the braiding 22 is always on the wall applied. With a particularly advantageous mixing ratio of 50% multifilament threads to 50% monofilament threads, the braided surface of the hose 10 also always remains closed. According to FIGS. 3 and 4, the elastic flat conductor arrangement 32, shown exaggeratedly thick in the sections of the drawings for purposes of illustration, is pressed by means of the braiding 22 to the elevations 36 of the wavy profile 34. In these contact areas, the elastic flat conductor arrangement 32 is thus held in a form-fitting manner in the radial direction of the hose 10 between the inner hose 12 and the braiding 22, while the pressing force directed radially with respect to the longitudinal axis 18 of the hose 10 is required for a non-positive, ie frictional, fixing in the longitudinal and in the circumferential direction of the hose 10 provides.

Axially between these contact areas, the flat conductor arrangement 32 can reversibly lengthen or compress due to its elastic design according to the deformation of the flexible hose 10 under the prevailing bending, torsional and/or tensile/compressive forces. This is illustrated in FIGS. 5 (below) and 6 for the case of elongation when the hose 10 is bent and in FIGS. 5 (above) and 7 for the case of compression when the hose 10 is bent.

Further details of the elastic flat conductor arrangement 32 can be seen in particular in FIGS. 6 to 8 and 10 (bottom left). Accordingly, the elastic flat conductor arrangement 32 has at least one, in the exemplary embodiment shown two, flexible stranded lines 46, 48. In the example shown, each of the stranded lines 46, 48 runs in a zigzag (alternatively in a serpentine form) as seen in the longitudinal direction of the flat conductor arrangement 32, in such a way that the stranded lines 46, 48, viewed transversely to the flat conductor arrangement 32, run in a zigzag (or serpentine) manner with an axial distance from one another, such as is best seen in FIG. The respective stranded wire 46, 48 is held in its course by threads 50, which in the manner of a knitted fabric around the respective Stranded wire 46, 48 form thread loops that are looped into stitches ver.

The individual threads 50 of the knitted fabric shown here are at least partially elastic and can, for example, comprise a mixture of polyester or polyamide fibers with elastane fibers. It is apparent to those skilled in the art that after the elastic flat conductor arrangement 32 is arranged on the outside 20 of the inner tube 12, viewed in its longitudinal direction, in alignment with the longitudinal axis 18 of the tube 10 (cf. FIGS. 2 and 8), the threads 50 of the knitted fabric on or in the hose 10 an elastic elongation - e.g. in the "outer curve" according to Fig. 5 (below) and 6 - or an elastic compression - for example in the "inner curve" according to Fig. 5 (above) and 7 - the respective stranded wire 46, 48 in its zigzag (or serpentine) course. In order to further increase the frictional connection of the elastic flat conductor arrangement 32 in its sandwiched position between the elevations 36 of the wavy profile 34 of the inner tube 12 and the sheathing 22, the flat conductor arrangement 32 can be provided with a (partial) rubber coating, for example by providing appropriate threads 50 in the knitted fabric of the flat conductor arrangement 32.

As far as the individual electrical conductors of the elastic flat conductor arrangement 32 are concerned, each of the stranded lines 46, 48 comprises a plurality of metallic individual wires, as indicated in FIG. 10 at the bottom left by reference numeral 52 by being fanned out at the line ends. Between the metallic individual wires, the respective stranded line 46, 48 can also have one or more plastic threads for strain relief. In the exemplary embodiment shown, the individual wires of each stranded cable 46, 48 are varnished for electrical insulation. As an alternative or in addition to this, the respective stranded wire can also be provided with an extruded plastic insulation (not shown in the figures). 10 further details of a possible connection piece 28 at the end 26 of the hose 10 are shown. In the exemplary embodiment shown here, the connection piece 28 has a contact area 54 which is electrically connected to the elastic flat conductor arrangement 32 and has two slip rings 56 . The two slip rings 56 of the contact area 54 are mounted at an axial distance from one another on a sleeve-shaped slip ring carrier 58 made of plastic, the peripheral surface shown in FIG. 10 is provided with screw projections 60 on its inner circumference. In the assembled state of the connection piece 28, the slip ring carrier 58 is screwed with its screw projections 60 onto the inner tube 12, more precisely its helical outer recesses 38, with the slip ring carrier 58 clamping the casing 22 onto the inner tube 12.

In this position, the slip ring carrier 58 is also fixed to the inner hose 12 by means of a collar sleeve 62, which is pressed into the inner hose 12 with a force fit so far that an annular collar 64 formed on the collar sleeve 62 is attached to a shoulder 66 (see Fig. 10) on the inner circumference of the slip ring carrier 58 comes to rest. Projections 68 provided on the outside of the annular collar 64 of the collar sleeve 62 engage in associated windows 70 in the slip ring carrier 58 so that the slip ring carrier 58 can no longer be rotated about the longitudinal axis 18 of the hose 10 .

According to FIGS. 1, 9 and 10 in particular, soldering lugs 72, 74 are provided on the slip rings 56, to which the stranded lines 46, 48 of the elastic flat conductor arrangement 32 are soldered, as indicated by dashed lines in FIG of the respective connection piece 28 to make electrical contact with the elastic flat conductor arrangement 32 . An elastomer ring seal 78 slipped onto an end ring extension 76 of the collar sleeve 62 completes the closing lent the respective fitting 28 of the flexible hose 10. During operation of the hose 10, this ring seal 78 serves to seal between the fitting 28 and an associated junction box (not shown).

A method for producing the flexible hose 10 described so far generally comprises the following three method steps a) to c): In a first step a), an inner hose 12 is formed, which with an inner side 14 delimits a cavity 16 about a longitudinal axis 18 and at least on an outer side 20 has a profile 34 which, seen in section, has a waveform with elevations 36 and depressions 38 Ver. The "basic hose" produced in this way is in principle already ready for use, i.e. if there are no special requirements in terms of electrical equipment or a sheathing or braiding, this basic hose can be assembled by cutting it to length and providing suitable connection pieces.

Only in a subsequent step b), when there are requirements for the hose 10 with regard to its electrical equipment, is the above-described elastic flat conductor arrangement 32 applied to the outside 20 of the inner hose 12, essentially without any prestressing, so that the elastic flat conductor arrangement 32 extends along the longitudinal axis 18 and transversely to the elevations 36 and depressions 38 of the profile 34 runs. In other words, in this step the hose 10 is provided with the desired electrical conductor 30, which, due to its configuration as an elastic flat conductor arrangement 32, is able to easily follow deformations of the hose 10, as already described above. Since the elastic flat conductor arrangement 32 runs along the inner tube 12, the use of (conductor) material and consequently also the tube weight are minimized compared to previously known solutions. Finally, in order to maintain this "electrified" state during further processing and later use of the hose 10, in a further step c) the elastic flat conductor arrangement 32 is fastened to the outside 20 of the inner hose 12 by attaching a sheathing 22 on the wavy profile 34 of the inner tube 12. As already mentioned above, this fastening can be done by braiding the outside 20 of the inner tube 12, if necessary with the help of an additional adhesive (adhesive or adhesive tape) on and/or under the elas tical flat conductor arrangement 32, in particular in the area of the elevations 36 of the wavy profile 34 of the inner tube 12.

Preferred sub-steps of step a) of forming the inner tube 12 include, as already mentioned above, first a sub-step in which a profile 39 is extruded from a plastic material. Then, in a further sub-step, the profile 39 is wound helically to form the inner tube 12, with adjacent windings of the profile 39 being connected to one another in a service-tight manner, e.g. by means of the hot-melt adhesive 40 me, as is known per se.

With regard to a particularly fast and efficient mass production of "electrified" flexible hoses 10, it is particularly preferred if steps b) of applying and c) of fastening the elastic flat conductor arrangement 32 on the outside 20 of the inner hose 12 are carried out at the same time . This can be done in particular by braiding monofilament and/or multifilament plastic threads around the wavy profile 34 of the inner tube 12 to form the sheathing 22, as is also known per se. However, this braiding then takes place with the special feature that the elastic flat conductor arrangement 32 in is applied to the outside 20 of the inner tube 12 substantially without pretension at the braiding point, so that after the braiding point the braided plastic threads press the elastic flat conductor arrangement 32 against the elevations 36 of the wavy profile 34 of the inner tube 12 .

It is obvious to a person skilled in the art that in this way, as part of a “continuous production”, inner hoses 12 of virtually any length can be “electrified” and provided with a sheathing 22 . After the desired hose length has been reached, the braided inner hose 12 provided with the elastic flat conductor arrangement 32 is then suitably cut to length before the further assembly of the hose 10 with the desired connecting pieces 28 can take place.

If, for example, the connecting piece 28 shown in FIGS. 1, 2, 9 and 10 is to be attached to the end 24 and/or 26 of the hose 10 as outlined, then the elastic flat conductor arrangement 32 or at least its stranded conductors is/are during the cutting to length or afterwards Pull 46, 48 slightly out of its position between the inner tube 12 and the casing 22, as indicated in FIG. 10 at the top left. As a result, the electrical conductors can be stripped and soldered to the soldering lugs 72, 74 of the slip rings 56 on the slip ring carrier 58 screwed onto the inner tube 12, whereupon the connection piece 28 can be fully assembled, as already mentioned above.

A flexible hose, in particular a vacuum cleaner hose, has an inner hose with a corrugated profile, the inside of which delimits a cavity for conveying media along a longitudinal axis, the outside of which is surrounded by an essentially smooth casing and at least one of the two ends with a connecting piece is provided. Radially between the inner hose and the jacket there is an electrical arranged shear conductor, which extends from one end to the end of the inner tube and ends in the connector for electrical contact. The electrical conductor is formed by an elastic flat conductor arrangement, which extends electrically insulated parallel to the longitudinal axis along the hose and is held on the wavy profile of the inner hose at least by the sheathing, which means that long, lightweight hoses equipped with electrical conductors can be used can be produced inexpensively. Furthermore, a method for producing such a hose in large numbers is proposed.

REFERENCE LIST

Hose

inner tube

inside

cavity

longitudinal axis

outside

sheathing, braiding

End

Connection piece for electrical conductors, elastic flat conductor arrangement, wavy profile

elevation

deepening

profile

hot melt adhesive

Inner surface

spiral groove

stranded wire

threads

fanning out

contact area

slip ring

slip ring carrier

screw protrusion

collar sleeve

ring collar

Unit volume

head Start

Window

solder tag Solder lug ring extension ring seal

Claims

PATENT CLAIMS :

1. Flexible hose (10), in particular a vacuum cleaner hose, with an inner hose that is profiled in a wavy manner

(12), which delimits a cavity (16) for conveying media along a longitudinal axis (18) of the hose (10) with an inside (14), surrounded on an outside (20) by a substantially smooth casing (22). and at least one of its two ends (24, 26) is provided with a connecting piece (28), an electrical conductor (30) being arranged radially between the inner tube (12) and the casing (22) and extending from the one End (24) extends to the other end (26) of the inner hose (12) and ends in the connecting piece (28) for establishing electrical contact, characterized in that the electrical conductor (30) is formed by an elastic flat conductor arrangement (32) which extends parallel to the longitudinal axis (18) along the hose (10) essentially without prestressing and electrically isolated and is held by the casing (22) on the corrugated profile (34) of the inner hose (12).

2. Flexible hose (10) according to claim 1, characterized in that the elastic flat conductor arrangement (32) by means of the sheathing (22) on elevations (36) of the corrugated profile (34) is pressed.

3. Flexible hose (10) according to claim 1 or 2, characterized in that the elastic flat conductor arrangement (32) is provided with a rubber coating.

4. Flexible hose (10) according to one of the preceding claims, characterized in that the sheathing (22) is a braiding of monofilament and/or multifilament plastic threads. 5. Flexible hose (10) according to one of the preceding claims, characterized in that the elastic flat conductor arrangement (32) has at least one stranded cable (46, 48) which is snake-shaped or zigzag-shaped in the longitudinal direction of the flat conductor arrangement (32). runs and is held in its course by threads (50), which form thread loops in the manner of a Ge active around the stranded wire (46, 48), which are intertwined to form meshes.

6. Flexible hose (10) according to claim 5, characterized in that the elastic flat conductor arrangement (32) has at least two stranded cables (46, 48) which, viewed transversely to the flat conductor arrangement (32), are at an axial distance from one another and are equally serpentine or zigzag.

7. Flexible hose (10) according to claim 5 or 6, characterized in that the stranded cable (46, 48) of the elastic flat conductor arrangement (32) has a plurality of individual metallic wires and at least one plastic thread for strain relief.

8. Flexible hose (10) according to any one of claims 5 to 7, characterized in that the stranded cable (46, 48) of the elastic flat conductor arrangement (32) is provided with an extruded insulation or enamelled.

9. Flexible hose (10) according to any one of claims 5 to 8, characterized in that the threads (50) of the knitted fabric are at least partially elastic, the threads (50) of the knitted fabric preferably being a mixture of polyester or polyamide include fibers with elastane fibers.

10. Flexible hose (10) according to any one of the preceding claims, characterized in that the connecting piece (28) has a contact area (54) with which the elastic Flat conductor arrangement (32) is electrically connected, wherein the contact area (54) preferably has at least one slip ring (56).

11. A method for producing a flexible hose (10), in particular according to one of the preceding claims, characterized by the following method steps: a) forming an inner hose (12) which has a cavity with an inside (14) about a longitudinal axis (18). (16) and has a profiling (34) on at least one outer side (20) which, viewed in section, has a wavy shape with elevations (36) and depressions (38), b) application of an elastic flat conductor arrangement (32) essentially free of prestressing on the outside (20) of the inner hose (12), so that the elastic flat conductor arrangement (32) runs along the longitudinal axis (18) and transversely to the elevations (36) and depressions (38) of the profile (34), and c) Fastening the elastic flat conductor arrangement (32) on the outside (20) of the inner tube (12) by attaching a sheathing (22) to the wavy profile

(34).

12. A method for producing a flexible hose (10) according to claim 11, characterized in that in step a) of forming the inner hose (12), first a profile (39) is extruded from a plastic material, whereupon the profile (39) for formation of the inner hose (12) is wound helically, with adjacent windings of the profile (39) being connected to one another in a media-tight manner.

13. A method for producing a flexible hose (10) according to claim 12, characterized in that the adjacent windings of the profile (39) are connected to one another in a media-tight manner by means of a hot-melt adhesive (40). 14. The method for producing a flexible hose (10) according to any one of claims 11 to 13, characterized in that steps b) of applying and c) of fastening the elastic flat conductor arrangement (32) on the outside (20) of the inner hose (12 ) can be carried out at the same time.

15. A method for producing a flexible hose (10) according to any one of claims 11 to 14, characterized in that the wavy profile (34) of the inner hose

(12) is braided with monofilament and/or multifilament plastic threads to form the sheathing (22), with the elastic flat conductor arrangement (32) being applied to the outside (20) of the inner hose (12) essentially without pretension at the braiding point, so that after the braiding point, the braided plastic threads press the elastic flat conductor arrangement (32) against the elevations (36) of the wavy profile (34) of the inner hose (12).