Monolithic ferrule for receiving and positioning multiple optical fibers and an optical fiber connector incorporating same

• US 5,727,101 A
• Filed: 10/06/1995
• Issued: 03/10/1998
• Est. Priority Date: 10/06/1995
• Status: Expired due to Term

• Current Assignee: Siecor Corporation (Corning Incorporated)
• Original Assignee: Siecor Corporation (Corning Incorporated)
• Inventors: Giebel, Markus A., Luther, James P.
• Primary Examiner(s): NGO, HUNG NHAT
• Application Number:
  US08/540,288
• Time in Patent Office: 886 Days
• Field of Search: 385/60-68, 385/72, 385/78-85
• US Class Current: 385/59
• CPC Class Codes: G02B 6/3834 Means for centering or aligning the light guide within the ferrule
• CPC Class Codes: G02B 6/3851 Ferrules having keying or coding means
• CPC Class Codes: G02B 6/3869 Mounting ferrules to connector body, i.e. plugs
• CPC Class Codes: G02B 6/3874 using tubes, sleeves to align ferrules
• CPC Class Codes: G02B 6/3885 Multicore or multichannel optical connectors, i.e. one single ferrule containing more than one fibre, e.g. ribbon type optical ribbon cable G02B6/4403, G02B6/448
• CPC Class Codes: G02B 6/3888 Protection from over-extension or over-compression
• CPC Class Codes: G02B 6/3893 Push-pull type, e.g. snap-in, push-on

Abstract

An optical fiber connector includes a connector housing and a monolithic ferrule disposed within the connector housing for maintaining a plurality of optical fibers in respective predetermined positions relative to the connector housing. The monolithic ferrule includes a monolithic ferrule body defining an internal cavity and a plurality of longitudinal bores through which the optical fibers extend. The optical fiber connector can also include an annular alignment key extending radially outward from the monolithic ferrule and having a position indicator adapted to mate with the connector housing such that the monolithic ferrule is held in a predetermined position relative to the connector housing. Accordingly, the optical fibers secured within the monolithic ferrule can be held in respective predetermined positions relative to the connector housing. The alignment key can be formed from the same piece of material from which the monolithic ferrule body is formed such that the alignment key is an integral part of the monolithic ferrule. The monolithic ferrule can also include ferrule alignment means for aligning the monolithic ferrule with another ferrule such that the optical fibers received by the longitudinal bores defined by the monolithic ferrule are aligned with the optical fibers secured within the other ferrule, thereby increasing the efficiency with which optical signals are transmitted therebetween.

Claims

1. An optical fiber connector comprising:

a connector housing having opposed first and second ends and defining an internal cavity opening through both the first and a monolith

a monolithic ferrule for maintaining a plurality of optical fibers in respective predetermined positions relative to said connector housing, said monolithic ferrule comprising a monolithic ferrule body extending longitudinally between opposed first and second ends and disposed within the internal cavity of said connector housing such that the first end of said monolithic ferrule body is exposed through the first end of said connector housing, said monolithic ferrule body also defining an internal cavity for receiving the plurality of optical fibers, wherein the internal cavity opens through the second end of said monolithic ferrule body and extends longitudinally through at least a portion of said monolithic ferrule body, said monolithic ferrule body also defining a plurality of longitudinal bores extending between the first end of said monolithic ferrule body and the internal cavity defined therein, wherein the longitudinal bores are adapted to receive respective ones of the plurality of optical fibers such that the optical fibers are maintained in respective predetermined positions relative to the monolithic ferrule body; and

an annular alignment key mounted to said monolithic ferrule and extending radially outward, wherein said alignment key includes a position indicator and is adapted to mate with said connector housing such that said monolithic ferrule is held in a predetermined position therein, and wherein the plurality of longitudinal bores are positioned in a predetermined angular relationship to the position indicator of said alignment key such that the optical fibers received by the longitudinal bores are maintained in respective predetermined positions to said connector housing.

2. An optical fiber connector according to claim 1 wherein said monolithic ferrule further comprises said annular alignment key such that said alignment key is an integral portion of said monolithic ferrule body.

3. An optical fiber connector according to claim 1 further comprising:

a ferrule sleeve having opposed first and second ends and defining a bore extending longitudinally therethrough such that a first end of said ferrule sleeve is capable of being mounted about at least a portion of said monolithic ferrule and such that a second end of said ferrule sleeve is capable of being mounted about at least a portion of a ferrule of another optical fiber connector; and

interlocking means for rotatably engaging said ferrule sleeve and the ferrule bodies about which said ferrule sleeve is mounted such that the rotatably engaged ferrule bodies are maintained in a predetermined aligned relationship.

4. An optical fiber connector according to claim 3 wherein said interlocking means comprises:

a slot defined by said monolithic ferrule body and extending both radially inward and longitudinally along an exterior surface thereof; and

a rib extending longitudinally along and radially into the bore defined by said ferrule sleeve to thereby engage a corresponding slot defined by each of the ferrule bodies such that the ferrule bodies are maintained by said ferrule sleeve in the predetermined aligned relationship.

5. An optical fiber connector according to claim 1 wherein the internal cavity defined by said monolithic ferrule body comprises first and second internal cavity portions adjacent the first and second ends of said monolithic ferrule body, respectively, and having respective predetermined sizes, and wherein the predetermined size of the second internal cavity portion is greater than the predetermined size of the first internal cavity portion to thereby facilitate the insertion of the plurality of optical fibers therein.

6. An optical fiber connector according to claim 1 wherein said monolithic ferrule body comprises a radially tapered nose portion adjacent the first end of said monolithic ferrule body, said radially tapered nose portion having an outer diameter which decreases in a longitudinal direction toward the first end of said monolithic ferrule body to thereby facilitate connection of the optical fiber connector.

7. A monolithic ferrule for maintaining a plurality of optical fibers in respective predetermined positions relative to an optical fiber connector, the monolithic ferrule comprising:

a monolithic ferrule body extending longitudinally between opposed first and second ends, said monolithic ferrule body defining an internal cavity for receiving the plurality of optical fibers, wherein the internal cavity opens through the second end of said monolithic ferrule body and extends longitudinally through at least a portion of said monolithic ferrule body,

said monolithic ferrule body also defining a plurality of longitudinal bores extending between the first end of said monolithic ferrule body and the internal cavity defined therein, wherein the longitudinal bores are adapted to receive respective ones of the plurality of optical fibers such that the optical fibers are maintained in respective predetermined positions relative to the monolithic ferrule body; and

an integral alignment key extending radially outward, wherein said integral alignment key includes a position indicator and is adapted to mate with the optical fiber connector such that said monolithic ferrule is held in a predetermined position therein, wherein the plurality of longitudinal bores are positioned in a predetermined angular relationship to the position indicator of said integral alignment key such that the optical fiber received by the longitudinal bores are maintained in respective predetermined positions to the optical fiber connector.

8. A monolithic ferrule according to claim 7 further comprising ferrule alignment means for aligning the monolithic ferrule with another ferrule such that the optical fibers received by the longitudinal bores defined by the monolithic ferrule are aligned with the optical fibers secured within the other ferrule.

9. A monolithic ferrule according to claim 8 wherein said ferrule alignment means comprises a slot defined by said monolithic ferrule body and extending both radially inward and longitudinally along an exterior surface thereof, said slot being adapted to receive a rib extending longitudinally along and radially into a bore defined by a ferrule sleeve which is mounted about both the first end of said monolithic ferrule body and the other ferrule such that the ferrule bodies are rotatably engaged and thereby maintained by the ferrule sleeve in the predetermined aligned relationship.

10. A monolithic ferrule according to claim 7 wherein the internal cavity defined by said monolithic ferrule body comprises first and second internal cavity portions adjacent the first and second ends of said monolithic ferrule body, respectively, and having respective predetermined sizes, and wherein the predetermined size of the second internal cavity portion is greater than the predetermined size of the first internal cavity portion to thereby facilitate the insertion of the plurality of optical fibers therein.

11. A monolithic ferrule according to claim 10 wherein the second internal cavity portion defined by said monolithic ferrule body further comprises a radially tapered portion adjacent the second end of said monolithic ferrule body to further facilitate the insertion of the plurality of optical fibers therein.

12. A monolithic ferrule according to claim 7 wherein said monolithic ferrule body comprises a radially tapered nose portion adjacent the first end of said monolithic ferrule body, said radially tapered nose portion having an outer diameter which decreases in a longitudinal direction toward the first end of said monolithic ferrule body.

13. A monolithic ferrule according to claim 7 wherein said monolithic ferrule body is comprised of a material selected from the group consisting of thermoplastic material and ceramic material.

14. A ferrule assembly for maintaining a plurality of optical fibers in respective predetermined positions, the ferrule assembly comprising:

a monolithic ferrule body extending longitudinally between opposed first and second ends, said monolithic ferrule body defining an internal cavity for receiving the plurality of optical fibers, wherein the internal cavity opens through the second end of said monolithic ferrule body and extends longitudinally through at least a portion of said monolithic ferrule body, said monolithic ferrule body also defining a plurality of longitudinal bores extending between the first end of said monolithic ferrule body and the internal cavity defined therein, wherein the longitudinal bores are adapted to receive respective ones of the plurality of optical fibers such that the optical fibers are maintained in respective predetermined positions relative to the monolithic ferrule body;

a ferrule sleeve having opposed first and second ends and defining a bore extending longitudinally therethrough such that a first end of said ferrule sleeve is capable of being mounted about at least a portion of said monolithic ferrule body and such that a second end of said ferrule sleeve is capable of being mounted about at least a portion of another ferrule body; and

interlocking means for rotatably engaging said ferrule sleeve and the ferrule bodies about which said ferrule sleeve is mounted such that the rotatably engaged ferrule bodies are maintained in a predetermined aligned relationship.

15. A ferrule assembly according to claim 14 wherein said interlocking means comprises:

a slot defined by said monolithic ferrule body and extending both radially inward and longitudinally along an exterior surface thereof; and

a rib extending longitudinally along and radially into the bore defined by said ferrule sleeve to thereby engage a corresponding slot defined by each of the ferrule bodies such that the ferrule bodies are maintained by said ferrule sleeve in the predetermined aligned relationship.

16. A ferrule assembly according to claim 14 wherein said monolithic ferrule body further comprises an integral alignment key extending radially outward therefrom, said integral alignment key including a position indicator and being adapted to mate with the optical fiber connector such that said monolithic ferrule body is held in a predetermined position therein, and wherein the plurality of longitudinal bores are positioned in a predetermined angular relationship to the position indicator of said integral alignment key such that the optical fibers received by the longitudinal bores are maintained in respective predetermined positions to the optical fiber connector.

17. A ferrule assembly according to claim 14 wherein the internal cavity defined by said monolithic ferrule body comprises first and second internal cavity portions adjacent the first and second ends of said monolithic ferrule body, respectively, and having respective predetermined sizes, and wherein the predetermined size of the second internal cavity portion is greater than the predetermined size of the first internal cavity portion to thereby facilitate the insertion of the plurality of optical fibers therein.

18. A ferrule assembly according to claim 14 wherein said monolithic ferrule body comprises a radially tapered nose portion adjacent the first end of said monolithic ferrule body, said radially tapered nose portion having an outer diameter which decreases in a longitudinal direction toward the first end of said monolithic ferrule body.