Armored cable

Abstract

Armored cable sheath is coded for easy visual identification by applying patterns, e.g., colored patterns, along the length of the cable. The sheath may be formed of a helically interlocked continuous strip of metal, or of smooth or corrugated continuous metal tubing. The patterns are applied on the outer surface of the sheath and are repeated along the length of the sheath.

What is claimed is:  
     
       1. An armored cable sheath comprising 
       a conductive tubular structure having an internal passage, an outer surface, a first end, and a second end, the internal passage being sized and configured to enclose one or more conductors, said tubular structure being made of a material having a first visual appearance, and  
       a pattern of visible indicia, of different visual appearance from said first visual appearance, applied on said outer surface, said pattern being repeated along the length of said sheath.  
     
     
       2. Apparatus comprising: 
       a tubular conductive sheath having first and second ends and inner and outer surfaces, the inner surface of the sheath defining an internal passage sized and configured to enclose one or more conductors;  
       visible indicia displayed on the outer surface of the sheath, the visible indicia spanning between the first and second ends of the sheath and providing the outer surface of the sheath with a visual appearance different from a visual appearance of the outer surface of the sheath without the visible indicia.  
     
     
       3. The apparatus of  claim 2  wherein the visible indicia comprise a pattern. 
     
     
       4. The apparatus of  claim 3  wherein the pattern repeats along the length of the sheath. 
     
     
       5. The apparatus of  claim 2  wherein the visible indicia comprise color. 
     
     
       6. The apparatus of  claim 5  wherein the visible indicia comprise red coloring. 
     
     
       7. The apparatus of  claim 5  wherein the visible indicia comprise anodized metal. 
     
     
       8. The apparatus of  claim 5  wherein the visible indicia comprise ink, dye, or paint. 
     
     
       9. The apparatus of  claim 8  wherein the ink, dye, or paint is substantially conductive. 
     
     
       10. The apparatus of  claim 8  wherein the ink, dye, or paint is substantially conductive. 
     
     
       11. The apparatus of  claim 2  wherein the visible indicia are continuous between the first and second ends of the sheath. 
     
     
       12. The apparatus of  claim 11  wherein the visible indicia comprise a stripe extending from the first end to the second end of the sheath. 
     
     
       13. The apparatus of  claim 12  wherein the stripe traverses a helical path around the outer surface of the sheath. 
     
     
       14. The apparatus of  claim 12  wherein the stripe substantially covers the outer surface of the sheath. 
     
     
       15. The apparatus of  claim 14  wherein the stripe is substantially conductive. 
     
     
       16. The apparatus of  claim 2  wherein the visible indicia are spaced apart along the length of the sheath between the first and second ends of the sheath such that regions disposed between adjacent indicia exhibit the visual appearance of the outer surface of the sheath. 
     
     
       17. The apparatus of  claim 16  wherein the visible indicia comprise a series of spots. 
     
     
       18. The apparatus of  claim 2  wherein the visible indicia leave at least a portion of the outer surface of the sheath exposed. 
     
     
       19. The apparatus of  claim 18  wherein the visible indicia leave at least a portion of the first and second ends of the outer surface exposed. 
     
     
       20. The apparatus of  claim 2  wherein the conductive sheath comprises a helically wound conductive strip forming a tubular structure with alternating crowns and valleys along the length of the sheath. 
     
     
       21. The apparatus of  claim 20  wherein the visible indicia leave at least a portion of the outer surface of the crowns exposed. 
     
     
       22. The apparatus of  claim 20  wherein the visible indicia leave at least a portion of the outer surface exposed where edges of the strip along the crowns contact a surface of the strip at the valleys. 
     
     
       23. The apparatus of  claim 2  wherein the conductive sheath comprises a continuous metal tubular structure. 
     
     
       24. The apparatus of  claim 23  wherein the outer surface of the continuous metal tubular structure is provided with alternating crowns and valleys along the length of the continuous metal tubular structure. 
     
     
       25. The apparatus of  claim 24  wherein the crowns and valleys form a helical configuration on the outer surface of the continuous metal tubular structure. 
     
     
       26. The apparatus of  claim 2  further comprising the one or more conductors disposed within the internal passage of the conductive sheath. 
     
     
       27. The apparatus of  claim 26  further comprising a layer of insulation disposed between the one or more conductors and the inner wall of the sheath. 
     
     
       28. The apparatus of  claim 27  wherein the insulation comprises paper. 
     
     
       29. The apparatus of  claim 27  wherein the insulation comprises plastic. 
     
     
       30. Apparatus comprising: 
       a tubular conductive sheath having first and second ends and inner and outer surfaces, the inner surface of the sheath defining an internal passage sized and configured to enclose one or more conductors;  
       a substantially conductive coating disposed on the outer surface of the sheath, the coating having a visual appearance different from a visual appearance of the outer surface of the sheath.  
     
     
       31. The apparatus of  claim 30  wherein the coating comprises ink, dye, or paint. 
     
     
       32. The apparatus of  claim 30  wherein the coating comprises a pattern. 
     
     
       33. The apparatus of  claim 32  wherein the pattern repeats along the length of the sheath. 
     
     
       34. The apparatus of  claim 33  wherein the pattern comprises a stripe extending along the length of the sheath. 
     
     
       35. Apparatus comprising: 
       
         a tubular conductive sheath having first and second ends and inner and outer surfaces, the inner surface of the sheath defining an internal passage sized and configured to enclose one or more conductors; and  
       
       
         visible indicia that permit electrical conductivity, are displayed along at least a portion of the sheath between the first and second ends of the sheath, and impart to the outer surface of the sheath a visual appearance different from a visual appearance of the outer surface of the sheath without the visible indicia. 
       
     
     
       36. The apparatus of  claim 35  in which the visible indicia comprise a substantially non- conductive material arranged to permit electrical conductivity.   
     
     
       37. The apparatus of  claim 35  in which the visible indicia comprise a removable coating of a substantially non- conductive material.   
     
     
       38. The apparatus of  claim 37  in which the removable coating comprises paint. 
     
     
       39. The apparatus of  claim 35  in which the visible indicia are arranged to expose at least a portion of the outer surface of the conductive sheath as necessary to assure that a connector attached to the sheath will make electrical contact with the outer surface of the sheath. 
     
     
       40. The apparatus of  claim 39  in which the visible indicia are arranged to expose at least a portion of the outer surface of the sheath by leaving uncoated areas on the outer surface. 
     
     
       41. The apparatus of  claim 35  in which the sheath is helically wound. 
     
     
       42. The apparatus of  claim 41  in which the visible indicia comprise a removable coating of a substantially non- conductive material arranged to expose at least a portion of the outer surface of the conductive sheath as necessary to assure that a connector attached to the sheath will make electrical contact with the outer surface of the sheath.   
     
     
       43. The apparatus of  claim 41  in which the visible indicia are arranged to expose at least a portion of the outer surface of the sheath by leaving uncoated areas on the outer surface. 
     
     
       44. The apparatus of  claim 41  in which the visible indicia permit electrical conductivity between successive windings of the sheath. 
     
     
       45. The apparatus of  claim 35  in which the conductive sheath comprises a continuous metal tubular structure. 
     
     
       46. The apparatus of  claim 45  in which the outer surface of the continuous metal tubular structure is provided with alternating crowns and valleys along the length of the continuous metal tubular structure. 
     
     
       47. The apparatus of  claim 46  in which the crowns and valleys form a helical configuration on the outer surface of the continuous metal tubular structure. 
     
     
       48. The apparatus of  claim 45  in which the outer surface of the continuous metal tubular structure is smooth along the length of the continuous metal tubular structure. 
     
     
       49. A method comprising: 
       
         providing a tubular conductive sheath having first and second ends and inner and outer surfaces, the inner surface of the sheath defining an internal passage sized and configured to enclose one or more conductors, the sheath bearing visible indicia that permit electrical conductivity, are displayed along at least a portion of the outer surface of the sheath between the first and second ends of the sheath, and impart to the outer surface of the sheath a visual appearance different from a visual appearance of the outer surface of the sheath without the visible indicia, and  
       
       
         attaching a connector to the sheath in such a manner that the connector makes electrical contact with the outer surface of the sheath. 
       
     
     
       50. The method of  claim 49  in which the visible indicia comprise a substantially non- conductive coating and the connector makes electrical contact with the outer surface notwithstanding the coating.   
     
     
       51. The method of  claim 50  in which the connector makes electrical contact with the outer surface at a location that is not coated.