Fiber-optic connector and method of assembly

• US 5,134,677 A
• Filed: 03/18/1991
• Issued: 07/28/1992
• Est. Priority Date: 02/15/1991
• Status: Expired due to Fees

• Current Assignee: Alcoa Fujikura Ltd. (Howmet Aerospace, Inc.)
• Original Assignee: Augat Communications Group Incorporated
• Inventors: Jensen, William S., Bertoglio fu Edoardo, Guido, Leung, Alexander M. C.
• Primary Examiner(s): Healy, Brian
• Application Number:
  US07/672,045
• Time in Patent Office: 498 Days
• Field of Search: 385/66, 385/60, 385/62, 385/78, 385/81, 385/84, 385/69, 385/86, 385/87, 385/70, 385/72, 385/139
• US Class Current: 385/84
• CPC Class Codes: G02B 6/3825 with an intermediate part, e.g. adapter, receptacle, linking two plugs
• CPC Class Codes: G02B 6/3847 with means preventing fibre end damage, e.g. recessed fibre surfaces
• CPC Class Codes: G02B 6/3854 Ferrules characterised by materials
• CPC Class Codes: G02B 6/3861 Adhesive bonding adhesives in general C09J
• 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 6/3878 comprising a plurality of ferrules, branching and break-out means
• CPC Class Codes: G02B 6/3888 Protection from over-extension or over-compression
• CPC Class Codes: G02B 6/3894 Screw-lock type

Abstract

A fiber-optic connector for a cable with an optical fiber. The connector includes a first backpost having an exteriorly threaded forward portion, a rearward portion attachable to the cable, and a central passageway extending therethrough. The connector has a body with a forward portion, an interiorly threaded rearward portion, and a central passageway extending therethrough. The body threads have a pitch diameter and pitch thread which mate with the threads of the first backpost. A second backpost is positioned within the body central passageway, and has a forward portion which holds a ferrule in position, and a rearward portion which extends through a rearward opening in the body and into a forward opening of the first backpost. The second backpost rearward portion and the first backpost central passageway are non-cylindrical to prevent rotation of the second backpost. The second backpost has an exteriorly threaded central portion with threads corresponding to the pitch diameter and thread pitch of the threads of the first backpost to allow the second backpost to threadably engage and upon rotation pass by the body interior threads when the second backpost is inserted within the body during assembly of the connector. A shoulder of the body projects radially inward sufficient to limit forward movement of the second backpost. A spring biases the second backpost in the forward direction. A coupling nut is positioned around the body and has a threaded forward end portion for threaded engagement with an adaptor. The connector is designed for easy interchange of coupling nuts having various connector styles.

Claims

1. A fiber-optic connector for a cable with an optic fiber, comprising:

a ferrule having a central passageway extending generally longitudinally fully through said ferrule to receive the optic fiber;

an elongated first backpost having an exteriorly threaded forward end portion, a rearward end portion attachable to the cable, and a central passageway extending generally longitudinally fully through said first backpost to receive the optic fiber, said first backpost exteriorly threaded portion having threads with a first pitch diameter and a first thread pitch, and said first backpost central passageway having a forward opening at said first backpost forward portion;

a body having a forward end portion, an interiorly threaded rearward end portion, and a central passageway extending generally longitudinally fully through said body, said body interiorly threaded portion having threads with said first pitch diameter, said first thread pitch and an interior thread diameter, said first backpost exteriorly threaded portion being threadably received by said body interiorly threaded portion, said body central passageway having a forward opening at said body forward portion defined by a shoulder which projects radially inward and a rearward opening at said body rearward portion;

an elongated second backpost positioned within said body central passageway and having forward and rearward end portions, said second backpost rearward portion extending rearwardly through said body rearward opening and into said first backpost forward opening, said second backpost forward portion terminating in a forwardly opening recess sized to receive and hold said ferrule in generally longitudinal alignment with said second backpost, said second backpost forward portion being disposed within said body central passageway for longitudinal movement of said second backpost relative to said body and having an outer dimension generally equal to or less than said interior thread diameter to freely pass by said body interior threads when said second backpost is inserted within said body central passageway during assembly of the connector, and said second backpost rearward portion being disposed within said first backpost central passageway for longitudinal movement of said second backpost relative to said first backpost, said first backpost central passageway and said body central passageway having a combined longitudinal length to permit forward and rearward longitudinal movement of said second backpost therewithin, said second backpost further having an exteriorly threaded central portion positioned between said second backpost forward and rearward portions, and a central passageway extending generally longitudinally fully through said second backpost to receive the optic fiber, said second backpost exteriorly threaded portion having threads with said first pitch diameter and said first thread pitch to allow said second backpost exterior threads to threadably engage and upon rotation pass by said body interior threads when said second backpost is inserted within said body central passageway during assembly of the connector prior to said body interiorly threaded portion threadably receiving said first backpost exteriorly threaded portion, said body shoulder projecting radially inward sufficient to limit forward longitudinal movement of said second backpost within said first backpost and body central passageways;

a spring positioned within said body about said second backpost rearward portion and between said first backpost forward portion and said second backpost central portion to bias said second backpost forwardly relative to said first backpost; and

a coupling member mounted to said body.

2. A fiber-optic connector for a cable with an optic fiber, comprising:

a ferrule having a central passageway extending generally longitudinally fully through said ferrule to receive the optic fiber;

an elongated first backpost having an exteriorly threaded forward end portion, a rearward end portion attachable to the cable, and a central passageway extending generally longitudinally fully through said first backpost to receive the optic fiber, said first backpost exteriorly threaded portion having threads with a first pitch diameter and a first thread pitch, and said first backpost central passageway having a forward opening at said first backpost forward portion;

a generally cylindrical body having a forward end portion, an interiorly threaded rearward end portion, and a central passageway extending generally longitudinally fully through said body, said body interiorly threaded portion having threads with said first pitch diameter, said first thread pitch and an interior thread diameter, said first backpost exteriorly threaded portion being threadably received by said body interiorly threaded portion to hold said body and said first backpost in substantial coaxial alignment, said body central passageway having a forward opening at said body forward portion defined by a shoulder which projects radially inward and a rearward opening at said body rearward portion;

an elongated second backpost positioned within said body central passageway and having forward and rearward end portions, said second backpost rearward portion extending rearwardly through said body rearward opening and into said first backpost forward opening, said second backpost forward portion engaging and holding said ferrule in generally longitudinal alignment with said second backpost, said second backpost forward portion being disposed within said body central passageway for longitudinal movement of said second backpost relative to said body and having an outer dimension generally equal to or less than said interior thread diameter to freely pass by said body interior threads when said second backpost is inserted within said body central passageway during assembly of the connector, and said second backpost rearward portion being disposed within said first backpost central passageway for longitudinal movement of said second backpost relative to said first backpost, said first backpost central passageway and said body central passageway having a combined longitudinal length to permit forward and rearward longitudinal movement of said second backpost therewithin, said second backpost further having an exteriorly threaded central portion positioned between said second backpost forward and rearward portions, said second backpost exteriorly threaded portion having threads with said first pitch diameter and said first thread pitch to allow said second backpost exterior threads to threadably engage and upon rotation pass by said body interior threads when said second backpost is inserted within said body central passageway during assembly of the connector prior to said body interiorly threaded portion threadably receiving said first backpost exteriorly threaded portion, said body shoulder projecting radially inward sufficient to limit forward longitudinal movement of said second backpost within said first backpost and body central passageways, said second backpost further having a central passageway extending generally longitudinally fully through said second backpost to receive the optic fiber, said second backpost being maintained within said body in substantial coaxial alignment with said first backpost with said first backpost central passageway and said second backpost central passageway in substantial coaxial alignment;

a spring positioned within said body about said second backpost rearward portion and between said first backpost forward portion and said second backpost central portion to bias said second backpost forwardly relative to said first backpost; and

a coupling member rotatably mounted to said body.

3. A fiber-optic connector for a cable with an optic fiber, comprising:

a ferrule having a central passageway extending generally longitudinally fully through said ferrule to receive the optic fiber;

an elongated first backpost having an exteriorly threaded forward end portion, a rearward end portion attachable to the cable, and a central passageway extending generally longitudinally fully through said first backpost to receive the optic fiber, said first backpost exteriorly threaded portion having threads with a first pitch diameter and a first thread pitch, and said first backpost central passageway having a forward opening at said first backpost forward portion and having a non-cylindrical interior wall portion positioned toward said first backpost forward opening;

a body having a forward end portion, an interiorly threaded rearward end portion, and a central passageway extending generally longitudinally fully through said body, said body interiorly threaded portion having threads with said first pitch diameter, said first thread pitch and an interior thread diameter, said first backpost exteriorly threaded portion being threadably received by said body interiorly threaded portion, said body central passageway having a forward opening at said body forward portion defined by a shoulder which projects radially inward and a rearward opening at said body rearward portion;

an elongated second backpost positioned within said body central passageway and having forward and rearward end portions, said second backpost rearward portion extending rearwardly through said body rearward opening and into said first backpost forward opening, said second backpost rearward portion having a non-cylindrical interior wall portion which extends within and mates with said first backpost non-cylindrical interior wall portion to permit longitudinal movement of said second backpost relative to said first backpost while preventing rotational movement therebetween, said second backpost rearward portion having sufficient length to position said second backpost non-cylindrical exterior wall portion within said first backpost non-cylindrical interior wall portion to prevent rotational movement therebetween prior to and when said body interiorly threaded rearward portion is being threaded onto said first backpost exteriorly threaded portion during assembly of the connector, said second backpost forward portion terminating in a forwardly opening recess sized to receive and hold said ferrule in generally longitudinal alignment with said second backpost, said second backpost forward portion being disposed within said body central passageway for longitudinal movement of said second backpost relative to said body and having an outer dimension generally equal to or less than said interior thread diameter to freely pass by said body interior threads when said second backpost is inserted within said body central passageway during assembly of the connector, and said second backpost rearward portion being disposed within said first backpost central passageway for longitudinal movement of said second backpost relative to said first backpost, said first backpost central passageway and said body central passageway having a combined longitudinal length to permit forward and rearward longitudinal movement of said second backpost therewithin, said second backpost further having an exteriorly threaded central portion positioned between said second backpost forward and rearward portions, and a central passageway extending generally longitudinally fully through said second backpost to receive the optic fiber, said second backpost exteriorly threaded portion having threads with said first pitch diameter and said first thread pitch to allow said second backpost exterior threads to threadably engage and upon rotation pass by said body interior threads when said second backpost is inserted within said body central passageway during assembly of the connector prior to said body interiorly threaded portion threadably receiving said first backpost exteriorly threaded portion, said body shoulder projecting radially inward sufficient to limit forward longitudinal movement of said second backpost within said first backpost and body central passageways;

a spring positioned within said body about said second backpost rearward portion and between said first backpost forward portion and said second backpost central portion to bias said second backpost forwardly relative to said first backpost; and

a coupling member mounted to said body.

4. The fiber-optic connector of claim 3 wherein said first backpost central passageway has a rearward passageway portion which extends forward from a rearward end of said first backpost to a midportion of said first backpost passageway and a forward passageway portion which extends rearward from a forward end of said first backpost to said midportion, said rearward passageway portion having a diameter sized to receive and provide lateral support to the optic fiber, and said forward passageway portion having a diameter larger than the diameter of said rearward passageway portion and sized to receive and permit longitudinal movement of said second backpost rearward portion therein, said forward passageway portion having a longitudinal length sized substantially equal to the length necessary for movement of said second backpost rearward portion to permit the desired compression of said spring by rearward movement of said second backpost during usage of the connector.

5. The fiber-optic connector of claim 3 for use with the optic fiber having a buffer, wherein said second backpost rearward portion has a rearward end, and said first backpost central passageway has a forward passageway portion and a rearward passageway portion, said rearward passageway portion having a diameter sized to receive and provide lateral support to a length of the optic fiber covered with the buffer, and said forward passageway portion having a diameter larger than the diameter of said rearward passageway portion and sized to receive and permit longitudinal movement of said second backpost rearward portion therein, said forward and rearward passageway portions having a forward facing annular shoulder extending therebetween, said second backpost rearward portion having a longitudinal length sufficient to position said rearward end thereof at a longitudinal distance from said shoulder when the connector is assembled and said spring biasing said second backpost fully forward which is equal to or less than five times the outside diameter of the buffered optic fiber.

6. A fiber-optic connector for a cable with an optic fiber, comprising:

a ferrule having a central passageway extending generally longitudinally fully through said ferrule to receive the optic fiber;

an elongated first backpost having an exteriorly threaded forward end portion, a rearward end portion attachable to the cable, and a central passageway extending generally longitudinally fully through said first backpost to receive the optic fiber, said first backpost exteriorly threaded portion having threads with a first pitch diameter and a first thread pitch, and said first backpost central passageway having a forward opening at said first backpost forward portion and having an interior wall portion positioned toward said first backpost forward opening;

a body having a forward end portion, an interiorly threaded rearward end portion, and a central passageway extending generally longitudinally fully through said body, said body interiorly threaded portion having threads with said first pitch diameter, said first thread pitch and an interior thread diameter, said first backpost exteriorly threaded portion being threadably received by said body interiorly threaded portion, said body central passageway having a forward opening at said body forward portion defined by a shoulder which projects radially inward and a rearward opening at said body rearward portion;

an elongated second backpost positioned within said body central passageway and having forward and rearward end portions, said second backpost rearward portion extending rearwardly through said body rearward opening and into said first backpost forward opening, said second backpost rearward portion having an exterior wall portion which extends within and engages said first backpost interior wall portion to permit longitudinal movement of said second backpost relative to said first backpost while preventing rotational movement therebetween, said second backpost rearward portion having sufficient length to position said second backpost interior wall portion within said first backpost exterior wall portion to prevent rotational movement therebetween prior to and when said body interiorly threaded rearward portion is being threaded onto said first backpost exteriorly threaded portion during assembly of the connector, said second backpost forward portion terminating in a forwardly opening recess sized to receive and hold said ferrule in generally longitudinal alignment with said second backpost, said second backpost forward portion being disposed within said body central passageway for longitudinal movement of said second backpost relative to said body and having an outer dimension generally equal to or less than said interior thread diameter to freely pass by said body interior threads when said second backpost is inserted within said body central passageway during assembly of the connector, and said second backpost rearward portion being disposed within said first backpost central passageway for longitudinal movement of said second backpost relative to said first backpost, said first backpost central passageway and said body central passageway having a combined longitudinal length to permit forward and rearward longitudinal movement of said second backpost therewithin, said second backpost further having an exteriorly threaded central portion positioned between said second backpost forward and rearward portions, and a central passageway extending generally longitudinally fully through said second backpost to receive the optic fiber, said second backpost exteriorly threaded portion having threads with said first pitch diameter and said first thread pitch to allow said second backpost exterior threads to threadably engage and upon rotation pass by said body interior threads when said second backpost is inserted within said central passageway during assembly of the connector prior to said body interiorly threaded portion threadably receiving said first backpost exteriorly threaded portion, said body shoulder projecting radially inward sufficient to limit forward longitudinal movement of said second backpost within said first backpost and body central passageways;

a spring positioned within said body about said second backpost rearward portion and between said first backpost forward portion and said second backpost central portion to bias said second backpost forwardly relative to said first backpost; and

a coupling member mounted to said body.

7. The fiber-optic connector of claim 6 wherein said first backpost central passageway has a rearward passageway portion which extends forward from a rearward end of said first backpost to a midportion of said first backpost passageway and a forward passageway portion which extends rearward from a forward end of said first backpost to said midportion, said rearward passageway portion having a diameter sized to receive and provide lateral support to the optic fiber, and said forward passageway portion having a diameter larger than the diameter of said rearward passageway portion and sized to receive and permit longitudinal movement of said second backpost rearward portion therein, said forward passageway portion having a longitudinal length sized substantially equal to the length necessary for movement of said second backpost rearward potion to permit the desired compression of said spring by rearward movement of said second backpost during usage of the connector.

8. The fiber-optic connector of claim 6 for use with the optic fiber having a buffer, wherein said second backpost rearward portion has a rearward end, and said first backpost central passageway has a forward passageway portion and a rearward passageway portion, said rearward passageway portion having a diameter sized to receive and provide lateral support to a length of the optic fiber covered with the buffer, and said forward passageway portion having a diameter larger than the diameter of said rearward passageway portion and sized to receive and permit longitudinal movement of said second backpost rearward portion therein, said forward and rearward passageway portions having a forward facing annular shoulder extending therebetween, said second backpost rearward portion having a longitudinal length sufficient to position said rearward end thereof at a longitudinal distance from said shoulder when the connector is assembled and said spring biasing said second backpost fully forward which is equal to or less than five times the outside diameter of the buffered optic fiber.

9. A fiber-optic connector for a cable with an optic fiber having a buffer, comprising:

a ferrule having a central passageway extending generally longitudinally fully through said ferrule to receive the optic fiber;

an elongated first backpost having a forward end portion, a rearward end portion attachable to the cable, and a central passageway extending generally longitudinally fully through said first backpost to receive the optic fiber, said first backpost central passageway having a forward opening at said first backpost forward portion, said first backpost central passageway having a rearward passageway portion which extends forward from a rearward end of said first backpost to a midportion of said first backpost passageway and a forward passageway portion which extends rearward from a forward end of said first backpost to said midportion, said rearward passageway portion having a diameter sized to receive and provide lateral support to the optic fiber;

a body having a forward end portion, a rearward end portion, and a central passageway extending generally longitudinally fully through said body, said body rearward portion being removably attached to said first backpost forward portion, said body central passageway having a forward opening at said body forward portion defined by a shoulder which projects radially inward and a rearward opening at said body rearward portion;

an elongated second backpost positioned within said body central passageway and having forward and rearward end portions, said second backpost rearward portion extending rearwardly through said body rearward opening and into said first backpost forward opening, said second backpost forward portion terminating in a forwardly opening recess sized to receive and hold said ferrule in generally longitudinal alignment with said second backpost, said second backpost forward portion being disposed within said body central passageway for longitudinal movement of said second backpost relative to said body, said second backpost rearward portion being disposed within said forward passageway portion of said first backpost central passageway for longitudinal movement of said second backpost relative to said first backpost, said first backpost central passageway and said body central passageway having a combined longitudinal length to permit forward and rearward longitudinal movement of said second backpost therewithin, said forward passageway portion of said first backpost central passageway having a diameter larger than the diameter of said rearward passageway portion and sized to receive and permit longitudinal movement of said second backpost rearward portion therein, said second backpost further having a central portion positioned between said second backpost forward and rearward portions, and a central passageway extending generally longitudinally fully through said second backpost to receive the optic fiber, said body shoulder projecting radially inward sufficient to limit forward longitudinal movement of said second backpost within said first backpost and body central passageways;

a spring positioned within said body about said second backpost rearward portion and between said first backpost forward portion and said second backpost central portion to bias said second backpost forwardly relative to said first backpost, said forward passageway portion of said first backpost central passageway having a longitudinal length sized substantially equal to the length necessary for movement of said second backpost rearward portion to permit the desired compression of said spring by rearward movement of said second backpost during usage of the connector; and

a coupling member mounted to said body.

10. A fiber-optic connector for a cable with an optic fiber, comprising:

a ferrule having a central passageway extending generally longitudinally fully through said ferrule to receive the optic fiber;

an elongated first backpost having a forward end portion, a rearward end portion attachable to the cable, and a central passageway extending generally longitudinally fully through said first backpost to receive the optic fiber, said first backpost central passageway having a forward opening at said first backpost forward portion, said first backpost central passageway having a forward passageway portion and a rearward passageway portion, said rearward passageway portion having a diameter sized to receive and provide lateral support to a length of the optic fiber covered with the buffer;

a body having a forward end portion, a rearward end portion, and a central passageway extending generally longitudinally fully through said body, said body rearward portion being removably attached to said first backpost forward portion, said body central passageway having a forward opening at said body forward portion defined by a shoulder which projects radially inward and a rearward opening at said body rearward portion;

an elongated second backpost positioned within said body central passageway and having forward and rearward end portions, said second backpost rearward portion extending rearwardly through said body rearward opening and into said first backpost forward opening, said second backpost forward portion terminating in a forwardly opening recess sized to receive and hold said ferrule in generally longitudinal alignment with said second backpost, said second backpost forward portion being disposed within said body central passageway for longitudinal movement of said second backpost relative to said body, said second backpost rearward portion having a rearward end and being disposed within said forward passageway portion of said first backpost central passageway for longitudinal movement of said second backpost relative to said first backpost, said first backpost central passageway and said body central passageway having a combined longitudinal length to permit forward and rearward longitudinal movement of said second backpost therewithin, said forward passageway portion of said first backpost central passageway having a diameter larger than the diameter of said rearward passageway portion and sized to receive and permit longitudinal movement of said second backpost rearward portion therein, said second backpost further having a central portion positioned between said second backpost forward and rearward portions, and a central passageway extending generally longitudinally fully through said second backpost to receive the optic fiber, said body shoulder projecting radially inward sufficient to limit forward longitudinal movement of said second backpost within said first backpost and body central passageways;

a spring positioned within said body about said second backpost rearward portion and between said first backpost forward portion and said second backpost central portion to bias said second backpost forwardly relative to said first backpost, said second backpost rearward portion having a longitudinal length sufficient to position said rearward end thereof at a longitudinal distance from said shoulder of said first backpost when the connector is assembled and said spring biasing said second backpost fully forward which is equal to or less than five times the outside diameter of the buffered optic fiber; and

a coupling member mounted to said body.

11. A fiber-optic connector for a cable with an optic fiber, comprising:

a ferrule having a central passageway extending generally longitudinally fully through said ferrule to receive the optic fiber;

an elongated first backpost having a forward end portion, a rearward end portion attachable to the cable, and a central passageway extending generally longitudinally fully through said first backpost to receive the optic fiber, said first backpost central passageway having a forward opening at said first backpost forward portion and having a non-cylindrical interior wall portion positioned toward said first backpost forward opening;

a body having a forward end portion, a rearward end portion, and a central passageway extending generally longitudinally fully through said body, said body rearward portion being removably attached to said first backpost forward portion, said body central passageway having a forward opening at said body forward portion defined by a shoulder which projects radially inward and a rearward opening at said body rearward portion;

an elongated second backpost positioned within said body central passageway and having forward and rearward end portions, said second backpost rearward portion extending rearwardly through said body rearward opening and into said first backpost forward opening, said second backpost rearward portion having a non-cylindrical exterior wall portion which extends within and mates with said first backpost non-cylindrical interior wall portion to permit longitudinal movement of said second backpost relative to said first backpost while preventing rotational movement therebetween, said second backpost rearward portion having sufficient length to position said second backpost non-cylindrical exterior wall portion within said first backpost non-cylindrical interior wall portion to prevent rotational movement therebetween prior to and when said body rearward portion is being attached to said first backpost forward portion during assembly of the connector, said second backpost forward portion terminating in a forwardly opening recess sized to receive and hold said ferrule in generally longitudinal alignment with said second backpost, said second backpost forward portion being disposed within said body central passageway for longitudinal movement of said second backpost relative to said body, said second backpost rearward portion being disposed within said first backpost central passageway for longitudinal movement of said second backpost relative to said first backpost, said first backpost central passageway and said body central passageway having a combined longitudinal length to permit forward and rearward longitudinal movement of said second backpost therewithin, said second backpost further having a central portion positioned between said second backpost forward and rearward portions, and a central passageway extending generally longitudinally fully through said second backpost to receive the optic fiber, said body shoulder projecting radially inward sufficient to limit forward longitudinal movement of said second backpost within said first backpost and body central passageways;

a spring positioned within said body about said second backpost rearward portion and between said first backpost forward portion and said second backpost central portion to bias said second backpost forwardly relative to said first backpost; and

a coupling member mounted to said body.

12. A fiber-optic connector for a cable with an optic fiber, comprising:

a ferrule having a central passageway extending generally longitudinally fully through said ferrule to receive the optic fiber;

an elongated first backpost having an exteriorly threaded forward end portion, a rearward end portion attachable to the cable, and a central passageway extending generally longitudinally fully through said first backpost to receive the optic fiber, said first backpost exteriorly threaded portion having threads with a first pitch diameter and a first thread pitch, and said first backpost central passageway having a forward opening at said first backpost forward portion;

a body having a forward end portion, an interiorly threaded rearward end portion, and a central passageway extending generally longitudinally fully through said body, said body interiorly threaded portion having threads with said first pitch diameter, said first thread pitch and an interior thread diameter, said first backpost exteriorly threaded portion being threadably received by said body interiorly threaded portion, said body central passageway having a forward opening at said body forward portion defined by a shoulder which projects radially inward and a rearward opening at said body rearward portion;

an elongated second backpost positioned within said body central passageway and having a forward end portion extending forwardly through said body forward opening and a rearward end portion extending rearwardly through said body rearward opening and into said first backpost forward opening, said second backpost forward portion terminating in a forwardly opening recess sized to receive and hold said ferrule in generally longitudinal alignment with said second backpost, said second backpost forward portion being disposed within said body forward opening for longitudinal movement of said second backpost relative to said body and having an outer dimension generally equal to or less than said interior thread diameter to freely pass by said body interior threads when said second backpost is inserted within said body central passageway during assembly of the connector, and said second backpost rearward portion being disposed within said first backpost central passageway for longitudinal movement of said second backpost relative to said first backpost, said first backpost central passageway and said body central passageway having a combined longitudinal length to permit forward and rearward longitudinal movement of said second backpost therewithin, said second backpost further having an exteriorly threaded central portion positioned between said second backpost forward and rearward portions, and a central passageway extending generally longitudinally fully through said second backpost to receive the optic fiber, said second backpost exteriorly threaded portion having threads with said first pitch diameter and said first thread pitch to allow said second backpost exterior threads to threadably engage and upon rotation pass by said body interior threads when said second backpost is inserted within said body central passageway during assembly of the connector prior to said body interiorly threaded portion threadably receiving said first backpost exteriorly threaded portion, said body shoulder projecting radially inward sufficient to engage said second backpost threads and limit forward longitudinal movement of said second backpost within said first backpost and body central passageways;

a spring positioned within said body about said second backpost rearward portion and between said first backpost forward portion and said second backpost central portion to bias said second backpost forwardly relative to said first backpost; and

a coupling member having a forward end portion, a rearward end portion and a central passageway extending generally longitudinally fully through said member, said member central passageway receiving said body therewithin with said ferrule extending forwardly through a forward opening of said member and said first backpost extending rearwardly through a rearward opening of said member, said member being freely rotatable relative to said body and said first backpost.

13. A fiber-optic connector for a cable with an optic fiber, comprising:

a ferrule having a central passageway extending generally longitudinally fully through said ferrule to receive the optic fiber;

an elongated first backpost having an exteriorly threaded forward end portion, a rearward end portion attachable to the cable, and a central passageway extending generally longitudinally fully through said first backpost to receive the optic fiber, said first backpost exteriorly threaded portion having threads with a first pitch diameter and a first thread pitch, and said first backpost central passageway having a forward opening at said first backpost forward portion;

a generally cylindrical body having a forward end portion, an interiorly threaded rearward end portion, and a central passageway extending generally longitudinally fully through said body, said body interiorly threaded portion having threads with said first pitch diameter, said first thread pitch and an interior thread diameter, said first backpost exteriorly threaded portion being threadably received by said body interiorly threaded portion to hold said body and said first backpost in substantial coaxial alignment, said body central passageway having a forward opening at said body forward portion defined by a shoulder which projects radially inward and a rearward opening at said body rearward portion;

an elongated second backpost positioned within said body central passageway and having a forward end portion extending forwardly through said body forward opening and a rearward end portion extending rearwardly through said body rearward opening and into said first backpost forward opening, said second backpost forward portion engaging and holding said ferrule in generally longitudinal alignment with said second backpost, said second backpost forward portion being disposed within said body forward opening for longitudinal movement of said second backpost relative to said body and having an outer dimension generally equal to or less than said interior thread diameter to freely pass by said body interior threads when said second backpost is inserted within said body central passageway during assembly of the connector, and said second backpost rearward portion being disposed within said first backpost central passageway for longitudinal movement of said second backpost relative to said first backpost, said first backpost central passageway and said body central passageway having a combined longitudinal length to permit forward and rearward longitudinal movement of said second backpost therewithin, said second backpost further having an exteriorly threaded central portion positioned between said second backpost forward and rearward portions, said second backpost exteriorly threaded portion having threads with said first pitch diameter and said first thread pitch to allow said second backpost exterior threads to threadably engage and upon rotation pass by said body interior threads when said second backpost is inserted within said body central passageway during assembly of the connector prior to said body interiorly threaded portion threadably receiving said first backpost exteriorly threaded portion, said body shoulder projecting radially inward sufficient to engage a forward end portion of said second backpost threads and limit forward longitudinal movement of said second backpost within said first backpost and body central passageways, said second backpost further having a central passageway extending generally longitudinally fully through said second backpost to receive the optic fiber, said second backpost being maintained within said body in substantial coaxial alignment with said first backpost with said first backpost central passageway and said second backpost central passageway in substantial coaxial alignment;

a spring positioned within said body about said second backpost rearward portion and between said first backpost forward portion and said second backpost central portion to bias said second backpost forwardly relative to said first backpost; and

a coupling member having a forward end portion, a rearward end portion and a central passageway extending generally longitudinally fully through said member, said member central passageway receiving said body therewithin with said ferrule extending forwardly through a forward opening of said member and said first backpost extending rearwardly through a rearward opening of said member, said member being freely rotatable relative to said body and said first backpost.

14. A method of assembling a fiber-optic cable having an optic fiber with a fiber-optic connector of one style which can be subsequently changed when desired to one of a plurality of additional styles without detaching the optic fiber or the cable components from the connector, comprising:

providing a ferrule having a central passageway extending generally longitudinally fully through said ferrule to receive the optic fiber, said ferrule having a length at least as long as required for the connector style requiring the longest exposed ferrule;

providing an elongated first backpost having an exteriorly threaded forward end portion, a rearward end portion attachable to the cable, and a central passageway extending generally longitudinally fully through said first backpost to receive the optic fiber, said first backpost exteriorly threaded portion having threads with a first pitch diameter and a first thread pitch, and said first backpost central passageway having a forward opening at said first backpost forward portion;

providing a plurality of bodies, each body having a forward end portion, an interiorly threaded rearward end portion, and a central passageway extending generally longitudinally fully through said body, said body interiorly threaded portion having threads with said first pitch diameter, said first thread pitch and an interior thread diameter, said first backpost exteriorly threaded portion being threadably received by said body interiorly threaded portion, said body central passageway having a forward opening at said body forward portion defined by a shoulder which projects radially inward and a rearward opening at said body rearward portion;

providing an elongated second backpost positioned within said body central passageway and having forward and rearward end portions, said second backpost rearward portion extending rearwardly through said body rearward opening and into said first backpost forward opening, said second backpost forward portion terminating in a forwardly opening recess sized to receive and hold said ferrule in generally longitudinal alignment with said second backpost, said second backpost forward portion being disposed within said body central passageway for longitudinal movement of said second backpost relative to said body and having an outer dimension generally equal to or less than said interior thread diameter to freely pass by said body interior threads when said second backpost is inserted within said body central passageway during assembly of the connector, and said second backpost rearward portion being disposed within said first backpost central passageway for longitudinal movement of said second backpost relative to said first backpost, said first backpost central passageway and said body central passageway having a combined longitudinal length to permit forward and rearward longitudinal movement of said second backpost therewithin, said second backpost further having an exteriorly threaded central portion positioned between said second backpost forward and rearward portions, and a central passageway extending generally longitudinally fully through said second backpost to receive the optic fiber, said second backpost exteriorly threaded portion having threads with said first pitch diameter and said first thread pitch to allow said second backpost exterior threads to threadably engage and upon rotation pass by said body interior threads when said second backpost is inserted within said body central passageway during assembly of the connector prior to said body interiorly threaded portion threadably receiving said first backpost exteriorly threaded portion, said body shoulder projecting radially inward sufficient to limit forward longitudinal movement of said second backpost within said first backpost and body central passageways;

providing a spring positioned within said body about said second backpost rearward portion and between said first backpost forward portion and said second backpost central portion to bias said second backpost forwardly relative to said first backpost;

providing a plurality of different style coupling members, each member being mounted to one of said plurality of bodies;

attaching said first backpost rearward portion to an end of the cable;

extending the optic fiber through said first backpost central passageway, said second backpost central passageway and said ferrule central passageway, and fixedly securing said optic fiber against removal from at least said ferrule central passageway;

assembling the connector using an initial selected style coupling member of said plurality of coupling members and using a corresponding initial one of said bodies; and

after the connector is initially fully assembled and it is desired to change to a selected different style coupling member of said plurality of coupling members, disconnecting said initial coupling member and initial body from the assembled connector by threadably removing said initial body from said first and second backposts, and then connecting said different style coupling member and corresponding body to the connector by threadably attaching said corresponding body with said different style coupling member mounted thereto without removing the secured optic fiber from said first backpost central passageway, said second backpost central passageway or said ferrule central passageway.

15. A method of assembling a fiber-optic cable having an optic fiber with a fiber-optic connector of one style which can be subsequently changed when desired to one of a plurality of additional styles without detaching the optic fiber or the cable components from the connector, comprising:

providing a ferrule having a central passageway extending generally longitudinally fully through said ferrule to receive the optic fiber, said ferrule having a length at least as long as required for the connector style requiring the longest exposed ferrule;

providing an elongated first backpost having a forward end portion, a rearward end portion attachable to the cable, and a central passageway extending generally longitudinally fully through said first backpost to receive the optic fiber, said first backpost central passageway having a forward opening at said first backpost forward portion;

providing a plurality of bodies, each body having a forward end portion, a rearward end portion, and a central passageway extending generally longitudinally fully through said body, said body rearward portion being removably attached to said first backpost forward portion, said body central passageway having a forward opening at said body forward portion defined by a shoulder which projects radially inward and a rearward opening at said body rearward portion;

providing an elongated second backpost positioned within said body central passageway and having forward and rearward end portions, said second backpost rearward portion extending rearwardly through said body rearward opening and into said first backpost forward opening, said second backpost forward portion terminating in a forwardly opening recess sized to receive and hold said ferrule in generally longitudinal alignment with said second backpost, said second backpost forward portion being disposed within said body central passageway for longitudinal movement of said second backpost relative to said body, said second backpost rearward portion being disposed within said first backpost central passageway for longitudinal movement of said second backpost relative to said first backpost, said first backpost central passageway and said body central passageway having a combined longitudinal length to permit forward and rearward longitudinal movement of said second backpost therewithin, said second backpost further having a central portion positioned between said second backpost forward and rearward portions, and a central passageway extending generally longitudinally fully through said second backpost to receive the optic fiber, said body shoulder projecting radially inward sufficient to limit forward longitudinal movement of said second backpost within said first backpost and body central passageways;

providing a spring positioned within said body about said second backpost rearward portion and between said first backpost forward portion and said second backpost central portion to bias said second backpost forwardly relative to said first backpost;

providing a plurality of different style coupling members, each member being mounted to one of said plurality of bodies;

attaching said first backpost rearward portion to an end of the cable;

extending the optic fiber through said first backpost central passageway, said second backpost central passageway and said ferrule central passageway, and fixedly securing said optic fiber against removal from at least said ferrule central passageway;

assembling the connector using an initial selected style coupling member of said plurality of coupling members and using a corresponding initial one of said bodies; and

after the connector is initially fully assembled and it is desired to change to a selected different style coupling member of said plurality of coupling members, disconnecting said initial coupling member and initial body from the assembled connector and then connecting said different style coupling member and corresponding body to the connector without removing the secured optic fiber from said first backpost central passageway, said second backpost central passageway or said ferrule central passageway.