Connector for fiber optic member including polishing fixture and method of terminating same

• US 4,648,688 A
• Filed: 03/25/1985
• Issued: 03/10/1987
• Est. Priority Date: 05/24/1982
• Status: Expired due to Term

• Current Assignee: AMP Limited
• Original Assignee: AMP Limited
• Inventors: Ashman, John J., Caron, Bernard G.
• Primary Examiner(s): Sikes, William L.
• Assistant Examiner(s): HEALY, BRIAN
• Application Number:
  US06/719,022
• Time in Patent Office: 715 Days
• Field of Search: 350/96.10, 350/96.15, 350/96.16, 350/96.20, 350/96.21, 350/96.22, 350/320, 350/96.18, 51/3, 51/4, 51/102, 51/103 R, 51/104, 51/105 R, 51/106 R, 51/128, 51/129, 51/132, 51/209 R, 51/210, 51/283 R, 51/170 T, 51/219 R , 51/DIG. 10, 51/170 MT
• US Class Current: 385/85
• CPC Class Codes: G02B 6/322 and having centering means being part of the lens for the self-positioning of the lightguide at the focal point, e.g. holes, wells, indents, nibs
• CPC Class Codes: G02B 6/3806 Semi-permanent connections, i.e. wherein the mechanical means keeping the fibres aligned allow for removal of the fibres dismountable connectors G02B6/3807
• CPC Class Codes: G02B 6/3825 with an intermediate part, e.g. adapter, receptacle, linking two plugs
• CPC Class Codes: G02B 6/3841 using rods, balls for light guides
• CPC Class Codes: G02B 6/3846 with fibre stubs
• CPC Class Codes: G02B 6/3855 characterised by the method of anchoring or fixing the fibre within the ferrule G02B6/3854 takes precedence
• CPC Class Codes: G02B 6/3857 Crimping, i.e. involving plastic deformation
• CPC Class Codes: G02B 6/3861 Adhesive bonding adhesives in general C09J
• CPC Class Codes: G02B 6/3863 fabricated by using polishing techniques grinding of the fibre ends B24B19/226
• CPC Class Codes: G02B 6/3865 fabricated by using moulding techniques shaping techniques of plastic materials in general B29C; producing plastic optical fiber connectors B29D11/0075
• CPC Class Codes: G02B 6/3874 using tubes, sleeves to align ferrules
• CPC Class Codes: G02B 6/3888 Protection from over-extension or over-compression
• CPC Class Codes: G02B 6/3894 Screw-lock type

Abstract

A connector for a fiber optic member comprises a ferrule member in which is positioned an insert having rods surrounding a section of an exposed end of the fiber optic member, the exposed end extending along a front bore of the ferrule member. A crimping ferrule on the ferrule member is controllably crimped thereon thereby moving the rods into mechanical engagement with the fiber optic member with no or minimum deformation to the fiber optic member and securing the fiber optic member in the ferrule member.

Claims

1. A polishing fixture for polishing a front end of a ferrule member and a front end of a fiber optic transmission member secured in a bore of the ferrule member, comprising:

a body member having a front flat surface and a profiled bore extending therethrough in which a profiled front end of the ferrule member is to be disposed with a front surface of the ferrule member extending outwardly beyond said front flat surface, said profiled bore being dimensioned to compress a front section of the ferrule member in tight engagement with the fiber optic transmission member in the bore of the ferrule member;

means for securing the ferrule member to said body member; and

means on said front flat surface to stabilize polishing of the front surface of the ferrule member and the front end of the fiber optic transmission member when the body member with said front section of said ferrule member secured therein is held against a polishing film and moved with respect thereto during the polishing thereof and to control the polishing so that the front surface of the ferrule member and the front end of the fiber optic transmission member are polished and are in the same plane.

2. A polishing fixture as set forth in claim 1, wherein said stabilizing and controlling means are buttons that extend outwardly from the front flat surface and are worn away during the polishing of the front surface of the ferrule member and the front end of the fiber optic transmission member indicating that said front surface of the ferrule member and said front end of the fiber optic transmission member are polished and are in the same plane.

12. A connector as set forth in claim 2 further characterized in that the end surface of said fiber optic member is in the same plane as the front surface of said ferrule member.

3. A connector for terminating a fiber optic member, comprising an insert member having a bore means extending therethrough, a ferrule member including a front section and a rear section and having an opening extending therethrough including front and rear bores in said front and rear sections respectively, and a crimping ferrule around said rear section of the ferrule member, said insert member receiving a fiber optic member insertably therethrough such that an end portion of said fiber optic member is spaced forwardly from said insert member with said fiber optic member therethrough being insertable into said opening of said ferrule member such that said end portion of said fiber optic member is disposable in said front bore of said ferrule member and said insert member is disposable in said rear bore in said rear section such that said fiber-engaging means of said insert member is positionable under said crimping ferrule, and said crimping ferrule is adapted to be controllably crimped to said rear section of said ferrule member simultaneously crimping said fiber-engaging means to said fiber optic member and crimping said ferrule member to said insert member thus terminating said fiber optic member, characterized in that:

said bore means of said insert member is a rod-receiving bore means,

said fiber-engaging means comprises a plurality of rod members contained in said rod-receiving bore means of said insert member and having a fiber-receiving opening therebetween, and at least central portions of said rod members are crimpable into securing engagement with said fiber optic member extending through said fiber-receiving opening.

4. A connector as set forth in claim 3 further characterized in that the material of said rod members is softer than the fiber optic member.

5. A connector as set forth in claim 4 further characterized in that said at least central portions of said rod members are deformed in cross-section during said crimping around said fiber optic member therebetween and are further deformed in cross-section where said rod members engage each other.

6. A connector as set forth in claim 3 further characterized in that said rod members are press fit into and frictionally held by said rod-receiving bore means prior to crimping.

7. A connector as set forth in claim 3 further characterized in that said rod-receiving bore means has a trifoliate configuration and said rod members are dumbbell shaped.

8. A connector as set forth in claim 7 further characterized in that said rod members are press fit into and frictionally held by said rod-receiving bore means prior to crimping.

9. A connector as set forth in claim 3 further characterized in that said rod-receiving bore has a trifoliate configuration and said rod members have a continuous diameter.

10. A connector as set forth in claim 9 further characterized in that said rod members are press fit into and frictionally held by said rod-receiving bore means prior to crimping.

11. A connector as set forth in claim 3 further characterized in that said fiber optic member is part of a fiber optic cable having strength members and an outer jacket, a metal ring positioned along said outer jacket and over which said strength members are positioned, said crimping ferrule extending along said metal ring and being controllably crimpable onto said metal ring in the area of said strength members to secure the strength members between the crimping ferrule and the metal ring to provide strain relief between said connector and said fiber optic cable.

13. A connector as set forth in claim 3 further characterized in that said ferrule member comprises a front cylindrical section, a central cylindrical section, a rear cylindrical section, and a conical section extending between said front and central cylindrical sections.

14. A connector as set forth in claim 3 further characterized in that a protective viscuous material is located in said ferrule member to protect the exposed end of the fiber optic member.

15. A connector as set forth in claim 3 further characterized in that a lens member is secured in said ferrule member with the end of the fiber optic member disposed therein.

16. A connector for terminating a fiber optic cable means comprising:

ferrule means having a front section and a rear section, said ferrule means having an opening extending therethrough including a front bore extending through said front section and a rear bore extending through said rear section;

insert means having a rod-receiving bore means extending therethrough in which a plurality of rod means are positioned, said plurality of rod means having a fiber-receiving opening therebetween to enable a fiber optic member of a fiber optic cable means to be inserted between said rod means such that an end portion of said fiber optic member is spaced forwardly from said insert means, said insert means with a section of the fiber optic member therewithin being positionable in said opening of said ferrule means with said end portion of said fiber optic member being disposed along said front bore and said insert means being disposed along said rear bore in said rear section of said ferrule means; and

crimping ferrule means on said rear section being controllably crimpable thereonto thereby reducing said rear section under said crimping ferrule means and moving at least central portions of said rod means in said insert means thereunder into securing engagement with the section of the fiber optic member thereunder thereby securing the insert means to the fiber optic member and the ferrule means to the insert means.

17. A connector as set forth in claim 16 wherein the material of said rod means is softer than the fiber optic member.

18. A connector as set forth in claim 17 wherein said at least central portions of said rod means are deformed in cross-section during said crimping around said fiber optic member therebetween and are further deformed in cross-section where said rod means engage each other.

19. A connector as set forth in claim 16 wherein said rod means are press fit into and frictionally held by said rod-receiving bore means prior to crimping.

20. A connector as set forth in claim 16 wherein said insert means includes a cylindrical section, said rod-receiving bore means having a trifoliate configuration with said rod means positioned in said bore means in said cylindrical section.

21. A connector as set forth in claim 20 wherein said rod means are dumbbell shaped.

22. A connector as set forth in claim 21 wherein said rod means are press fit into and frictionally held by said rod-receiving bore means prior to crimping.

23. A connector as set forth in claim 20 wherein said rod means have a continuous diameter.

24. A connector as set forth in claim 23 wherein said rod means are press fit into and frictionally held by said rod-receiving bore means prior to crimping.

25. A connector as set forth in claim 16 further comprising ring means positionable along an outer jacket of said fiber optic cable means, said crimping ferrule means controllably crimpable onto said ring means and strength means of the fiber optic cable means.

26. A connector as set forth in claim 16 wherein said opening through said ferrule means includes a conical bore extending between said front and rear bores and a viscous protective material is disposed in said opening.

27. A connector as set forth in claim 16 wherein an end surface of the end portion of the fiber optic member is coincident with a front surface of said front section.

28. A connector as set forth in claim 16 wherein said ferrule means is resilient.

29. A connector as set forth in claim 16 wherein lens means is secured in said front bore and an end of the fiber optic member is disposed in said lens means.

30. A method of terminating a connector onto an end of fiber optic cable means, characterized by the steps of:

placing an insert member having rod members there in and a fiber-receiving opening between said rod members onto a section of a fiber optic member of the fiber optic cable means with an end portion of the fiber optic member spaced forwardly therefrom;

inserting said insert member with the section of the fiber optic member therein into an opening of a ferrule member with the end portion of the fiber optic member disposed in a front section of said opening and said insert member disposed in a rear section of said ferrule member; and

controllably crimping a crimping ferrule on said rear section of said ferrule member thereby reducing said rear section and moving the rod members in said insert member thereunder into securing engagement with the section of the fiber optic member which secures the fiber optic member in said insert member and said insert member in said ferrule member.

31. A method as set forth in claim 30 further characterized by the further step of scribing and breaking or cleaving the end of the fiber optic member extending out from a front surface of said ferrule member, at said front surface.

32. A method as set forth in claim 31 further characterized by the further steps of placing the ferrule member in a fixture with a slight section of said front surface extending beyond an outer surface of said fixture;

and

moving said fixture along a polishing film thereby polishing the end of the fiber optic means.

33. A method as set forth in claim 30 further characterized by the further step of positioning a ring member along an outer jacket of the fiber optic cable means with strength means of the fiber optic cable means being positioned on the ring member and controllably crimping said crimping ferrule onto the strength means and said ring member thereby securing said crimping ferrule onto said ring member with the strength means therebetween.

34. A method as set forth in claim 30 further characterized in that said rod members are press fit into and frictionally held by said insert member prior to said placing step.