VERFAHREN ZUR UNMANTELUNG VON STRANGFÖRMIGEN ELEMENTEN

Abstract

The invention relates to a method for jacketing strandlike elements (10), comprising the method steps of: a) producing or providing a strandlike element (10), b) wrapping the strandlike element (10) with an adhesive tape (12) to give a wrapped strand (14), the adhesive tape (12) comprising as curable adhesive a radiation-curing and/or thermally curing adhesive, c) arranging the wrapped strand (14) in one or more holding elements (16) of a holding arrangement (18) to establish a predetermined shape and to give a shaped strand (20), and d) curing the curable adhesive in the shaped strand (20) by irradiating the adhesive tape (12) with electromagnetic radiation of a wavelength λ, to give a jacketed strand (22), wherein the one or the two or more holding elements (16) at least in sections are at least partly transmissive for electromagnetic radiation of wavelength λ, wherein the irradiation of the adhesive tape (12) with the electromagnetic radiation of wavelength λ takes place at least partly through the one or the two or more holding elements (16).

Claims

1. Method for jacketing strandlike elements (10), comprising the method steps of: a) producing or providing a strandlike element (10), b) wrapping the strandlike element (10) with an adhesive tape (12) to give a wrapped strand (14), the adhesive tape (12) comprising as curable adhesive a radiation-curing and/or thermally curing adhesive which is preferably at the same time pressure-sensitively adhesive, c) arranging the wrapped strand (14) in one or more holding elements (16) of a holding arrangement (18) to establish a predetermined shape and to give a shaped strand (20), and d) curing the curable adhesive in the shaped strand (20) by irradiating the adhesive tape (12) with electromagnetic radiation of a wavelength λ, to give a jacketed strand (22), wherein the one or the two or more holding elements (16) at least in sections are at least partly transmissive for electromagnetic radiation of wavelength λ, wherein the irradiation of the adhesive tape (12) with the electromagnetic radiation of wavelength λ takes place at least partly through the one or the two or more holding elements (16).

2. Method according to claim 1, wherein the adhesive tape (12) comprises as curable adhesive a radiation-curing adhesive, wherein the radiation-curing adhesive is preferably a UV-curable adhesive, wherein the UV-curable adhesive more preferably is curable by irradiation with electromagnetic radiation having a wavelength in the range from 10 to 380 nm, especially preferably in the range from 200 to 380 nm.

3. Method according to claim 1, wherein the adhesive tape (12) comprises as curable adhesive a thermally curable adhesive, wherein the thermally curable adhesive is preferably configured such that the thermal curing can be promoted and/or brought about, preferably brought about, by electromagnetic radiation in the infrared range, more preferably electromagnetic radiation having a wavelength in the range from 780 nm to 1 mm, especially preferably in the range from 780 nm to 50 μm, more particularly preferably in the range from 780 nm to 3 μm.

4. Method according to claim 1, wherein the adhesive tape (12) comprises a carrier, the curable adhesive being arranged at least partly on the surface of the carrier.

5. Method according to claim 4, wherein the carrier at least in sections comprises a carrier material which is at least partly, preferably substantially completely, transmissive for electromagnetic radiation of wavelength λ.

6. Method according to claim 1, wherein the adhesive tape comprises or preferably consists of a carrier and a curable adhesive coated on the carrier and in the form of a radiation-curing and/or thermally curing adhesive which is applied over the full area and which at the same time is pressure-sensitively adhesive.

7. Method according to claim 1, wherein the one or the two or more holding elements (16) are the receiving regions, provided for receiving the wrapped strand (14), of one or more carrier elements (24a-c) of the holding arrangement (18), the holding elements (16) and/or the carrier elements (24a-c) being connected preferably reversibly and non-destructively partably to the holding arrangement (18).

8. Method according to claim 1, wherein the one or the two or more holding elements (16) over the entire length are at least partly transmissive for electromagnetic radiation of wavelength λ.

9. Method according to claim 1, wherein the one or the two or more holding elements (16) at least in sections are transmissive to an extent of 30% or more, preferably 50% or more, more preferably 70% or more, more preferably 90% or more, especially preferably 95% or more, for electromagnetic radiation of wavelength λ, based on the ratio of the total intensity of the electromagnetic radiation of wavelength λ irradiated onto the holding element (16) to the total intensity of the electromagnetic radiation of wavelength λ passing through the holding element (16).

10. Method according to claim 1, wherein the one or the two or more holding elements (16) are formed at least in sections, preferably to an extent of 50% or more, more preferably 70% or more, especially preferably 90% or more, more particularly preferably substantially completely, of a material which is at least partly transmissive for electromagnetic radiation of wavelength λ, the material preferably having an absorption coefficient a for electromagnetic radiation of wavelength λ of 1.0 1/cm or less, preferably of 0.7 1/cm or less, more preferably of 0.4 1/cm or less, especially preferably of 0.2 1/cm or less.

11. Method according to claim 1, wherein the wrapped strand (14) is arranged in the one or more holding elements (16) such that more than 30%, preferably more than 50%, more preferably more than 70%, especially preferably more than 90%, more particularly preferably more than 95%, of the wrapped strand (14) is arranged in the one or the two or more holding elements, based on the length of the wrapped strand (14) or on the length of that part of the shaped strand (20) that is irradiated with electromagnetic radiation, preferably based on the length of that part of the shaped strand (20) that is irradiated with electromagnetic radiation.

12. Method according to claim 1, wherein the wrapped strand (14), after being arranged in the one or more holding elements (16), is covered, preferably covered and secured, at least in sections, preferably completely, by one or more covering elements (26), the one or the two or more covering elements (26) at least in sections being at least partly transmissive for electromagnetic radiation of wavelength λ, the irradiation of the adhesive tape (12) with the electromagnetic radiation of wavelength λ taking place at least partly through the one or the two or more covering elements (26).

13. Method according to claim 1, wherein the curable adhesive is cured with a radiation device (28), preferably a UV lamp and/or an IR lamp, more preferably a UV lamp, the radiation device (28) being preferably configured to surround the shaped strand (20) at least partly, preferably substantially form-fittingly, and to irradiate the shaped strand with electromagnetic radiation of wavelength λ at least in sections over 70% or more, preferably 80% or more, more preferably 90% or more, especially preferably 95% or more, of the extent.

14. Method according to claim 1, wherein the curing in method step d) before the irradiation comprises a preheating of the shaped strand (20) at a temperature T.sub.1 in the range from 20 to 60° C., preferably in the range from 30 to 50° C., and/or wherein the curing in method step d) takes place by irradiation at a temperature T.sub.2 in the range from 20 to 90° C., preferably in the range from 30 to 80° C., more preferably in the range from 40 to 70° C., and/or wherein the curing in method step d) after the irradiation comprises an aftercuring at a temperature T.sub.3 in the range from 60 to 150° C., preferably in the range from 70 to 140° C., more preferably in the range from 80 to 130° C.

15. Holding arrangement (18) for establishing a predetermined shape of a shaped strand (20) in a method according to claim 1, comprising one or more holding elements (16) for receiving the wrapped strand (14), wherein the one or the two or more holding elements (16) at least in sections are at least partly transmissive for electromagnetic radiation of wavelength λ, wherein the one or the two or more holding elements (16) are part of one or more carrier elements (24a-c) of the holding arrangement (18), the holding elements (16) and/or carrier elements (24a-c) being connected preferably reversibly and non-destructively partably to the holding arrangement (18).

16. System (30) for implementing the method according to claim 1, comprising a holding arrangement (18) according to claim 15, and a radiation device (28), preferably a UV lamp and/or an IR lamp, more preferably a UV lamp, the radiation device (28) being preferably configured to surround a shaped strand (20) at least partly, preferably substantially form-fittingly, and to irradiate the shaped strand (20) with electromagnetic radiation of wavelength λ at least in sections over 70% or more, preferably 80% or more, more preferably 90% or more, especially preferably 95% or more, of the extent.

Description

[0087] Described and elucidated in more detail below are preferred embodiments of the invention with reference to the appended figures, in which:

[0088] FIG. 1 shows a schematic representation of the method of the invention at a first point in time in one preferred embodiment;

[0089] FIG. 2 shows a schematic representation of the method of the invention at a second point in time in one preferred embodiment;

[0090] FIG. 3 shows a schematic representation of the method of the invention at a third point in time in one preferred embodiment;

[0091] FIG. 4 shows a schematic representation of the method of the invention at a fourth point in time in one preferred embodiment;

[0092] FIG. 5 shows a schematic representation of the method of the invention at a fifth point in time in one preferred embodiment; and

[0093] FIG. 6 shows a schematic representation of the method of the invention at a sixth point in time in one preferred embodiment.

[0094] FIG. 1 shows a schematic representation of the method of the invention at a first point in time. The strandlike element 10 provided for the jacketing in the example shown is a cable strand which comprises a multiplicity of cables joined to one another by the use of adhesive tape in order to facilitate handling of the strandlike element 10; accordingly, it would also be possible, additionally or alternatively, to use cable ties and clips. This strandlike element 10 is part of a macrostructure, specifically a complete cable loom as envisaged for a motor vehicle; in FIG. 1, for reasons of clarity, only a portion has been shown.

[0095] It is indicated in FIG. 1 that the strandlike element 10 is wrapped with an adhesive tape 12, to obtain a wrapped strand 14 in the wrapped region. In the example shown, this wrapping takes place in helical lines around the strandlike element 10, with each subsequent turn lying about half on the preceding turn. The strandlike element 10 shown in FIG. 1 is already wrapped here to about half with adhesive tape 12, this being indicated by the dashed line.

[0096] The adhesive tape 12 comprises a curable adhesive, which for improved application is implemented as a pressure-sensitive adhesive. In the example shown, this curable adhesive is radiation-curing. More particularly the curable adhesive is curable by irradiation with electromagnetic radiation of wavelength A in the ultraviolet range, more particularly in the range from 200 to 380 nm. In the example shown, the adhesive tape 12 comprises a porous nonwoven in which the curable adhesive is embedded in a mass fraction of about more than 50%. The nonwoven in this case is formed of a plastic which is partly transmissive for electromagnetic radiation of wavelength λ in the ultraviolet range. The curable adhesive is based on the systems disclosed in EP 3693433 A1 and comprises, for example, as well as photo-initiator (mass fraction 1%), an epoxy resin (mass fraction 65%) and a matrix polymer (mass fraction 34%).

[0097] In the example shown, the holding arrangement 18 comprises three carrier elements 24a, 24b and 24c of equal length, each with a fork-shaped holder at the end, and the middle carrier element 24b is offset backwards, so that the carrier elements 24a-24c span a triangle. Inserted into the fork of the carrier elements 24a-24c in FIG. 1 is a holding element 16, which through a form-fit is joined reversibly and non- destructively partably to the carrier elements 24a-24c. This holding element 16, indicated by the dashed line, is implemented in this case as a bent half-tube having a semicircular cross section which is formed completely of polymethyl methacrylate, which at the selected thickness for the tube side wall has a transmissiveness of more than 95% for electromagnetic radiation of the wavelength λ used in the UV range, and so the intensity of the electromagnetic radiation of the corresponding wavelength that impinges through the holding element 16 onto the wrapped or shaped strand 20 is reduced by less than 5% during irradiation.

[0098] Shown in FIG. 2 then, on the basis of FIG. 1, is how the wrapped strand 14 is arranged in the holding element 16, this being accomplished by insertion of the wrapped strand 14 into the tubular receptacle of the holding element 16, with the wrapped strand 14 adopting the shape dictated by the holding element 16 and thereby becoming the shaped strand 20, which, based on the length of that part of the shaped strand 20 that is subsequently cured with electromagnetic radiation, lies in the holding element 16 to an extent of more than 80%.

[0099] FIG. 3 then shows how the shaped strand 20 in the holding element 16 is additionally covered, over the entire length of the holding element 16, with a covering element 26 that is complementary to said holding element 16 and that is likewise formed as a half-tube of polymethyl methacrylate. This covering element 26 covers and fastens the shaped strand 20. In this case it is indicated in FIG. 3 that the shaped strand 20 in the radiation device 28 is preheated prior to curing to a temperature of about 40° C. in order to realize a preferred regime.

[0100] As shown in FIG. 4, the shaped strand 20 prepared according to FIG. 3 is subsequently cured by irradiation of the adhesive tape 12 in the shaped strand 20 with electromagnetic radiation of a wavelength in the ultraviolet range. This takes place in a system 30 of the invention, which comprises a radiation device 28, presently implemented as a radiation box, in which the UV lamps arranged are shielded from the outside world by the surrounding box. In this case, for the curing by means of irradiation, a temperature of about 50° C. is established inside the radiation device. As evident in FIG. 4, the electromagnetic radiation of wavelength λ in the ultraviolet range is applied through the holding element 16 and through the covering element 26, which by virtue of the material selected are each largely transmissive for electromagnetic radiation of the corresponding wavelength essentially over the entire length and the entire extent.

[0101] In FIG. 5, the UV lamps of the radiation device 28 are deactivated and an aftercure takes place at a temperature of about 100° C. Lastly it can be seen in FIG. 6 how the covering element 26 is removed, allowing the withdrawal of the jacketed strand 22, i.e. the strandlike element 10 surrounded by the cured adhesive tape 12 and having the predetermined shape.

LIST OF REFERENCE SYMBOLS

[0102] 10 Strandlike element [0103] 12 Adhesive tape [0104] 14 Wrapped strand [0105] 16 Holding element [0106] 18 Holding arrangement [0107] 20 Shaped strand [0108] 22 Jacketed strand [0109] 24a-c Carrier elements [0110] 26 Covering element [0111] 28 Radiation device [0112] 30 System