Method for stranding profile strands

• US 4,604,860 A
• Filed: 12/20/1984
• Issued: 08/12/1986
• Est. Priority Date: 01/23/1984
• Status: Expired due to Term

• Current Assignee: Sumitomo Electric Industries Limited (Sumitomo Corporation)
• Original Assignee: Sumitomo Electric Industries Limited (Sumitomo Corporation)
• Inventors: Miyazaki, Kenji, Matsuura, Takayuki
• Primary Examiner(s): Watkins, Donald
• Application Number:
  US06/683,925
• Time in Patent Office: 600 Days
• Field of Search: 57/6, 57/9, 57/138, 57/215, 57/311, 57/3, 57/12, 57/13, 57/33, 57/282, 57/290, 57/309
• US Class Current: 57/9
• CPC Class Codes: D07B 1/0693 having a strand configuration
• CPC Class Codes: D07B 1/147 comprising electric conductors or elements for information transfer D07B1/145 takes precedence
• CPC Class Codes: D07B 2201/2002 characterised by their cross-sectional shape
• CPC Class Codes: D07B 2201/2011 comprising metals
• CPC Class Codes: D07B 2201/2023 with core
• CPC Class Codes: D07B 2201/2027 Compact winding
• CPC Class Codes: D07B 2201/2039 three to eight wires or filaments respectively forming a single layer
• CPC Class Codes: D07B 2201/2047 Cores
• CPC Class Codes: D07B 2201/2096 Light guides
• CPC Class Codes: D07B 2205/3025 Steel
• CPC Class Codes: D07B 2205/306 Aluminium (Al)
• CPC Class Codes: D07B 2207/404 Heat treating devices; Corresponding methods
• CPC Class Codes: D07B 2401/2015 Killing or avoiding twist
• CPC Class Codes: D07B 2801/14 Core
• CPC Class Codes: D07B 2801/18 Coating
• CPC Class Codes: D07B 5/12 of low twist or low tension by processes comprising setting or straightening treatments
• CPC Class Codes: D07B 7/025 Preforming the wires or strands prior to closing
• CPC Class Codes: D07B 7/04 Devices for imparting reverse rotation to bobbin- or reel cages
• CPC Class Codes: G02B 6/4407 with internal fluted support member G02B6/4429, G02B6/4439, G02B6/4479 take precedence
• CPC Class Codes: G02B 6/4489 of central supporting members of lobe structure
• CPC Class Codes: H01B 13/02 : Stranding-up

Abstract

A method of stranding profiled strands comprises the steps of stranding a plurality of profiled strands (7) together around an optical fiber conductor or cable (2) which serves as a central core while imparting twist to each profiled strand by the use of a rigid type stranding machine, and then heat-treating the strands (7) along with the optical fiber conductor or cable (2) so as to remove strains or stress from the heat treated strands.

Claims

1. A method of stranding profiled strands for forming a cable, comprising the steps of first spirally stranding a plurality of profiled strands (7) together around a central core means while imparting twist to each profiled strand to form said cable and then heat-treating said plurality of profiled strands (7) in said cable together with said core means, said heat-treating step taking place in a temperature range and for a time duration sufficient for removing stress from said profiled strands.

2. The method of claim 1, comprising providing a heater downstream of stranding tool means as viewed in a cable feed advance direction, for performing said heating step after said step of stranding has been carried out by said stranding tools.

3. The method of claim 1, comprising using steel wires as said profiled strands (7), said steel wires having a tensile strength of at least 60 kg/mm².

4. The method of claim 3, wherein said heat-treating is carried out within a temperature range of 200°

-500°

C.

5. The method of claim 1, further comprising providing said central core means in the form of an optical fiber conductor means.

6. The method of claim 1, further comprising using strands having a cross-sectional shape which is substantially sectorial.

7. The method of claim 1, further comprising winding said cable onto a bobbin and placing said bobbin (12) having wound thereon said cable with the plurality of profiled strands (7) into a heating chamber for performing said heat-treating step.

8. The method of claim 1, wherein said heat-treating step is carried out before said cable is wound onto a bobbin (12), but subsequent to said stranding.

9. The method of claim 8, wherein said heat-treating step is carried out by passing said cable through a heating chamber on the way from the wire stranding step to the step of winding the cable on the bobbin.

10. The method of claim 9, comprising using as said heating chamber a high frequency induction heating device, and further performing a simultaneous cooling step by cooling the cable directly with water.

11. The method of claim 3, further comprising coating said steel wires with an aluminum cover prior to said stranding step.

12. The method of claim 1, further comprising providing said cable with an aluminum pipe forming a cable core, and then stranding said profiled strands onto said aluminum pipe.

13. A method of stranding profiled strands for forming a cable, comprising the steps of providing steel wire strands having a substantially sectorial cross-sectional shape, spirally stranding a plurality of said sectorial steel wire strands together around a central core of an optical fiber conductor means, while imparting twist to each sectorial steel wire strand to form said cable, heat-treating said plurality of sectorial steel wire strands in said cable together with said central core for removing stress from said sectorial steel wire strands, wherein said heat treating step is performed by passing said cable through an elongated pipe (32) surrounded by an induction heating device and simultaneously passing cooling water through said elongated pipe (32), and then winding said cable after said heat-treating step onto a bobbin (12).

14. The method of claim 13, further comprising providing said sectorial steel wire strands with an aluminum cover.

15. The method of claim 13, further comprising providing said central core of said optical fiber conductor means with an aluminum pipe forming a shell for optical conductor fibers and simultaneously said central core for said cable.