CABLE SEAL AND METHOD OF MANUFACTURE

Abstract

A method of manufacturing a cable seal is provided, the method including the steps of providing a cable having a protective outer jacket of a non-PVC material; preparation of the protective outer jacket of the cable such as to promote adhesion with a sealant; and overmolding the outer jacket with a sealant. As a result, a sealing interface is formed between the jacket and the sealant.

Claims

1. A method of manufacturing a cable seal, the method comprising: providing a cable having a protective outer jacket of a non-polyvinyl chloride material; preparing the protective outer jacket of the cables to promote adhesion with a sealant; and overmolding the outer jacket with a sealant.

2. The method according to claim 1, wherein the sealant is a polyurethane material, optionally a polyurethane foam material.

3. The method of according to claim 1, wherein the step of preparing the protective outer jacket comprises: applying a tape onto the protective outer jacket of the cable.

4. The method according to claim 3, wherein the tape is an adhesive tape.

5. The method according to claim 3, wherein the tape is a polyvinyl chloride tape.

6. The method according to claim 3, wherein the tape is a polyethylene terephthalate tape.

7. The method according to claim 6, wherein the tape is a polyethylene terephthalate fabric tape.

8. The method according to claim 1, wherein the step of preparing the protective outer jacket comprises: applying a cold melt onto the protective outer jacket of the cable.

9. The method according to claim 1, wherein the overmolded sealant is formed as a grommet, splice or plug.

10. The method according to claim 1, wherein an elastic seal is positioned around the outer jacket.

11. The method according to claim 1, further comprising the steps of: providing a heat shrinkable sleeve; positioning the heat shrinkable sleeve over the protective outer jacket with an adhesive between the heat shrinkable sleeve and the outer jacket; heat shrinking the sleeve; and overmolding the sleeve and an adjacent region of the outer jacket with a sealant

12. The method according to claim 11, wherein the sleeve is made of a polyvinyl chloride, polyvinyl chloride, polyvinylidene fluoride, or fluorinated ethylene propylene material.

13. The method according to claim 11, wherein the adhesive is applied to an inner surface of the sleeve.

14. The method according to claim 11, wherein the seal is made of a rubber material, a polytetrafluoroethylene material, or a silicone material.

15. The method according to claim 1, wherein the step of preparing the protective outer jacket comprises: plasma treating or corona treating the protective outer jacket of the cable.

16. The method according to claim 1, wherein the step of preparing the protective outer jacket comprises: chemically treating the protective outer jacket of the cable with a solvent.

17. The method according to claim 1, wherein the step of preparing the protective outer jacket comprises: mechanically treating the protective outer jacket of the cable, the mechanical treatment comprising at least one of: roughening the protective outer jacket using an abrasive material; sand blasting the protective outer jacket; soda blasting the protective outer jacket; or brushing the protective outer jacket.

18. A cable seal comprising a cable having a protective outer jacket, and an overmolded sealant, manufactured using a method comprising: providing a cable having a protective outer jacket of a non-polyvinyl chloride material; preparing the protective outer jacket of the cables to promote adhesion with a sealant; and overmolding the outer jacket with a sealant.

19. The cable according to claim 18, wherein the sealant is made of a polyurethane material.

20. The cable according to claim 19, wherein the sealant is made of a polyurethane foam material.

21. The cable seal according to claim 18, comprising a sleeve comprising a polyvinyl chloride, polyvinyl chloride, polyvinylidene fluoride, or fluorinated ethylene propylene material.

22. The cable seal according to claim 21, wherein an elastic seal is positioned around the outer jacket.

23. The cable seal according to claim 22, wherein the elastic seal is made of a rubber material, a polytetrafluoroethylene material, or a silicone material.

24. The cable seal according to claim 22, wherein the elastic seal is a sealing ring provided with grooves in its inner circumference.

25. The cable seal according to claim 22, wherein the elastic seal is a sealing ring provided with grooves on its outer circumference.

26. The cable seal according to claim 22, wherein the elastic seal is a sealing ring and wherein the sleeve encapsulates the sealing ring.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0027] The present invention will now be described, by way of example with reference to the accompanying drawings, in which:

[0028] FIG. 1 illustrates an embodiment of a cable seal;

[0029] FIG. 2 illustrates a further embodiment of a cable seal;

[0030] FIG. 3 illustrates a further embodiment of a cable seal;

[0031] FIG. 4 illustrates a plasma treatment of a cable;

[0032] FIG. 5 illustrates a cross-section through a cable seal according to a further embodiment;

[0033] FIG. 6 illustrates a cross-section of a further embodiment of cable seal; and

[0034] FIG. 7 illustrates a cross-section of a further embodiment of cable seal.

DETAILED DESCRIPTION

[0035] FIG. 1 depicts a cable seal 10, the cable including one or more electrical or optical conductors 12 surrounded by a protective outer jacket 14 made of a non-PVC material, e.g., a polyolefin, polyethylene, or silicone material.

[0036] The cable seal 10 includes a splice, e.g., a copper splice 26 connecting the three electrical conductors 12. In the region of the copper splice 26 the cable seal 10 is provided with an overmolded sealant 24, e.g., of a polyurethane foam material. To improve the adhesion between the outer jackets 14 and the sealant 24 an adhesive PVC tape 30, e.g., of class T3 or T4, is wrapped around the outer protective jackets 14 next to the copper splice 26. The overmolded sealant 24 is applied with an excellent adhesion between the sealant 24 and the outer jackets 14 of the cables.

[0037] FIG. 2 depicts a further embodiment of a cable seal similar to the embodiment of FIG. 1 wherein the preparation of the protective outer jackets 14 is performed by applying a cold melt 32 onto the outer jackets 14 and onto the copper splice 26.

[0038] FIG. 3 depicts a further embodiment of a cable seal wherein sealing rings 34 of a rubber or silicone material are applied onto the protective outer jackets adjacent to the copper splice 26 to promote adhesion of the overmold of the sealant 24 and to provide a watertight sealing.

[0039] FIG. 4 depicts a cable including an electrical conductor 12 surrounded by an insulating jacket 14 wherein a plasma head 40 including a plasma nozzle 42 is used for treating the protective outer jacket 14 with a plasma beam 44 resulting in a plasma treated area 46 extending over the circumference of the outer jacket 14 which is made of a non-PVC material, e.g., of a XLPE material, or polyolefins, copolymers of polyolefins, crosslinked polyolefins, and their co-polymers.

[0040] FIG. 5 depicts a cross-section of a cable seal including the cable shown in FIG. 4 which has been overmolded with a sealant 24 of polyurethane foam. The preparation of the protective outer jacket 14 through application of atmospheric plasma significantly promotes the adhesion of the overmolded sealant 24 to the outer jacket 14.

[0041] In an embodiment of a cable seal 10 as disclosed in FIG. 6 the cable extends through an opening in a wall 20. Before the cable seal 10 is inserted into the opening of the wall 20, a sleeve 15 which is made of heat shrinkable material (e.g., a polyvinyl chloride (PVC), polyvinylidene fluoride (PVDF), or fluorinated ethylene propylene (FEP) material) is positioned over the cable with an adhesive 17 being provided between the sleeve 15 and the outer jacket 14. The adhesive 17 may be provided as an adhesive layer on the inner circumference of the sleeve 15. Alternatively, the adhesive 17 may be provided as a separate sleeve or may be applied directly onto the outer jacket 14. After a placement of the sleeve 15 over the outer jacket 14 with the adhesive 17 between the sleeve 15 and the jacket 14 the sleeve 15 is heat shrunk onto the cable seal 10 wherein the adhesive 17 serves to fix against an axial displacement of the sleeve 15.

[0042] Thereafter, the cable may be inserted into the opening of the wall 20 such that the sleeve 15 extends through the opening and the sleeve 15 is provided with an overmolding of sealant 24 (e.g., PUR sealant), and the sealant may form a seal in the form of a grommet to seal and isolate against humidity and water.

[0043] FIG. 7 depicts a further embodiment of a cable seal with the same reference numerals used for the same elements.

[0044] The cable seal of FIG. 7 generally corresponds to the embodiment of FIG. 6 with similar components having the same reference numerals. An elastic sealing ring 16 is positioned between the adhesive 17 and the outer jacket 14 of the cable seal 10. As shown in the drawing, the elastic sealing ring 16 may be serrated e.g., by providing annular groves at the inner or outer circumference such as to provide improved sealing properties and an interlocking between the sealing ring 16 and the adhesive 17 on the one hand and the sealing ring 16 and the outer jacket 14 on the other hand. The sealing ring 16 may be made of a rubber, a PTFE, or a silicone material. For example, the sealing ring 16 may be made of ethylene propylene rubber (EPR), nitrile butadiene rubber (NBR), Standard Indonesia Rubber (SIR), fluororubber (FPM), Ethylene acrylic rubber (AEM), fluorosilicone, fluorocarbon, or polyacrylate rubber.

[0045] In this embodiment a sleeve 15′ is heat shrunk onto the outer jacket 14 such as to encapsulate the sealing ring 16 not only at its outer circumference but also on both opposite side surfaces. However, this is merely an optional feature and not mandatory.

[0046] In both embodiments the overmold of sealant 24 fully encapsulates the sleeve 15 and the adhesive 17.