Optical fiber connector using fiber spring force alignment groove

• US 5,757,997 A
• Filed: 12/22/1995
• Issued: 05/26/1998
• Est. Priority Date: 12/22/1995
• Status: Expired due to Term

• Current Assignee: 3M Company
• Original Assignee: 3M Company
• Inventors: Borer, Victor J., Birrell, Barbara L., Lee, Nicolas A., Henson, Gordon D., Doss, Donald G., Igl, Scott A.
• Primary Examiner(s): Bovernick, Rodney B.
• Assistant Examiner(s): Sanghavi, Hemang
• Application Number:
  US08/577,740
• Time in Patent Office: 886 Days
• Field of Search: 385/55, 385/56, 385/57, 385/58, 385/60, 385/65, 385/72, 385/75, 385/76, 385/78, 385/83, 385/97, 385/98, 385/99, 385/19, 385/25, 385/139, 385/140, 385/134, 385/135
• US Class Current: 385/60
• CPC Class Codes: B08B 11/00 Cleaning flexible or delicate articles by methods or apparatus specially adapted thereto B08B3/12, B08B6/00 take precedence
• CPC Class Codes: B08B 2240/02 Optical fibers or optical fiber connectors
• CPC Class Codes: B08B 7/0028 by adhesive surfaces
• CPC Class Codes: G02B 2006/4297 having protection means, e.g. protecting humans against accidental exposure to harmful laser radiation
• CPC Class Codes: G02B 6/3805 with a fibre-supporting member inclined to the bottom surface of the alignment means
• CPC Class Codes: G02B 6/3821 with axial spring biasing or loading means G02B6/3847 takes precedence
• CPC Class Codes: G02B 6/3823 containing surplus lengths, internal fibre loops provisionally see also G02B6/444
• CPC Class Codes: G02B 6/3829 Bent or angled connectors G02B6/3827 takes precedence
• CPC Class Codes: G02B 6/3838 using grooves for light guides
• CPC Class Codes: G02B 6/3847 with means preventing fibre end damage, e.g. recessed fibre surfaces
• CPC Class Codes: G02B 6/3849 using mechanical protective elements, e.g. caps, hoods, sealing membranes G02B6/3816 takes precedence; provisionally see H01R13/44
• CPC Class Codes: G02B 6/3866 Devices, tools or methods for cleaning connectors cleaning in general B08B
• 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
• CPC Class Codes: G02B 6/421 the intermediate optical component consisting of a short length of fibre, e.g. fibre stub
• CPC Class Codes: G02B 6/4292 the light guide being disconnectable from the opto-electronic element, e.g. mutually self aligning arrangements

Abstract

A fiber optic connector comprising a plug and a receptacle uses the spring force supplied by bowing of the plug fiber to maintain a continuous compressive load at the fiber joint located in a fiber-alignment groove. The plug has a holder for securing the plug fiber and a shroud which snaps onto the holder with the plug fiber extending generally straight inside the shroud. The shroud has a slot providing access to the terminal portion of the plug fiber, and a sliding door which selectively covers the slot. The receptacle includes a housing and another fiber holder for securing the receptacle fiber, with a projection or finger attached to the receptacle fiber holder, the projection having the fiber-alignment groove. The finger is oriented within the receptacle housing such that, when the plug is inserted into the receptacle, the finger extends through the slot in the shroud at an oblique angle with respect to the plug axis. In this manner, as the plug is inserted, the end of the plug fiber slides into the fiber-alignment groove in the finger and comes into contact. With the end face of the receptacle fiber. Continued insertion results in bowing of the plug fiber to achieve the compressive load. The plug door may have camming surfaces which are actuated by corresponding surfaces on a door of the receptacle. The connector may be used to simultaneously interconnect a plurality of fiber pairs, or to terminate a fiber to an active optical device.

Claims

1. A plug for terminating or interconnecting an optical fiber, comprising:

means for securely holding a terminal portion of the fiber;

an elongate, hollow plug body attached to said fiber holding means such that the terminal portion of the fiber extends into an interior of said plug body generally parallel to an axis of said plug body, said interior having sufficient space to allow the terminal portion of the fiber to bow within said interior, and said plug body having at least one opening providing access to the terminal portion of the fiber from an oblique angle with respect to said plug body axis;

wherein said access opening comprises a slot located at a forward end of said plug body, and further comprising a door member attached to said plug body, movable between a closed position wherein said door member covers said slot and an open position wherein said slot is unobstructed by said door member.

2. The plug of claim 1, wherein said plug body is mechanically polarized.

3. The plug of claim 1, wherein said door member slides sideways across said forward end of said plug body.

4. The plug of claim 3, wherein said door member has a camming surface adapted to urge said door member sideways upon insertion of the plug in a receptacle.

5. A plug for terminating or interconnecting an optical fiber, comprising:

means for securely holding a terminal portion of the fiber;

an elongate, hollow plug body attached to said fiber holding means such that the terminal portion of the fiber extends into an interior of said plug body generally parallel to an axis of said plug body, said interior having sufficient space to allow the terminal portion of the fiber to bow within said interior, and said plug body having at least one opening providing access to the terminal portion of the fiber from an oblique angle with respect to said plug body axis;

wherein said fiber holding means comprises;

a first block having a landing member extending in a direction toward the terminal portion of the fiber, said landing member having upstanding posts which limit skewing of the terminal portion of the fiber; and

a second block positioned adjacent said first block, at least one of said first and second blocks having a fiber-receiving groove at an adjacent surface.

6. The plug of claim 5 wherein said landing member has attached thereto latch means for releasably securing said plug body to a receptacle.

7. A optical fiber termination comprising:

a plug having a plug fiber holder securing a bare, terminal portion of an optical fiber, and an elongate, hollow plug body having first and second ends, said first end being open and attached to said plug fiber holder with said terminal portion of said fiber extending into an interior of said plug body generally parallel to an axis of said plug body, said interior having sufficient space to allow said terminal portion of said fiber to bow within said interior, and said second end having a slot providing access to said terminal portion of said fiber;

a receptacle having an opening sized to receive said second end of said plug body, said receptacle further-having a projection adapted to enter said slot in said plug body, said projection having a fiber-alignment groove therein located to receive said terminal portion of said fiber when said plug body is inserted in said receptacle; and

latch means for releasably securing said plug body in said receptacle.

8. The optical fiber termination of claim 7, further comprising means for biasing said plug body in an exit direction from said receptacle opening.

9. The optical fiber termination of claim 7, further comprising means for releasing said latch means when a predetermined tension is placed on said plug fiber.

10. The optical fiber termination of claim 7, further comprising a door member attached to said plug body, movable between a closed position wherein said door member covers said slot and an open position wherein said slot is unobstructed by said door member.

11. The optical fiber termination of claim 7, wherein said receptacle further has a receptacle fiber holder securing a bare, terminal portion of another optical fiber whose end face is located along an intermediate section of said fiber-alignment groove.

12. The optical fiber termination of claim 7, wherein said plug fiber holder comprises:

a first block having a landing member extending in a direction toward the terminal portion of the fiber, said landing member having upstanding posts which limit skewing of said terminal portion of said fiber; and

a second block positioned adjacent said first block, at least one of said first and second blocks having a fiber-receiving groove at an adjacent surface.

13. The optical fiber termination of claim 10, wherein:

said door member slides sideways across said second end of said plug body;

said door member has a camming surface adapted to urge said door member sideways; and

said receptacle has a door member having a corresponding camming surface adapted to cam against said camming surface of said plug door member upon insertion of said plug body in said receptacle.

14. The optical fiber termination of claim 11, further comprising fiber hold-down means for securely retaining said receptacle fiber in an apex of said fiber-alignment groove.

15. A fiber optic connector comprising:

a plug including

a plug fiber holder securing a bare, terminal portion of an optical fiber,

an elongate, hollow plug shroud having first and second ends, said first end being open and attached to said plug fiber holder with said terminal portion of said fiber extending into an interior of said plug shroud generally parallel to an axis of said plug shroud, said interior having sufficient space to allow said terminal portion of said fiber to bow within said interior, and said second end having a slot providing access to said terminal portion of said fiber; and

a receptacle including

a receptacle housing having an opening sized to receive said second end of said plug shroud, said plug shroud further having means for releasably securing said plug shroud in said receptacle housing,

a receptacle fiber holder securing a bare, terminal portion of another optical fiber, said receptacle fiber holder having a projection adapted to enter said slot in said plug shroud at an oblique angle with respect to said plug shroud axis, said projection having a fiber-alignment groove therein located to receive said terminal portion of said plug fiber when said plug shroud is inserted in said receptacle, an end face of said receptacle fiber being located along an intermediate section of said fiber-alignment groove, and

means for releasably mounting said receptacle housing to a support surface;

whereby said plug fiber extends generally straight within said plug shroud when said plug is removed from said receptacle, but is sufficiently long such that when said plug is fully inserted in said receptacle, said plug fiber becomes bowed to maintain a continuous compressive load against said end face of said receptacle fiber.

16. The fiber optic connector of claim 15, wherein:

said plug further includes a plug door slidably attached to said second end of said plug shroud, having a closed position wherein said plug door covers said slot and an open position wherein said slot is unobstructed by said plug door; and

said receptacle further includes a receptacle door hingedly attached to said receptacle housing at said opening, having means for urging said plug door to said open position as said second end of said plug shroud is inserted into said receptacle housing.

17. A fiber optic connector comprising:

a plug including

a plug fiber holder securing a terminal portion of an optical fiber,

an elongate, hollow plug shroud attached to said plug fiber holder with said terminal portion of said fiber extending into an interior of said plug shroud, said plug shroud having a forward end with a slot providing access to said terminal portion of said fiber, and

a plug door slidably attached to said end of said plug shroud, having a closed position wherein said plug door covers said slot and an open position wherein said slot is unobstructed by said plug door; and

a receptacle including

a receptacle housing having an opening sized to receive said second end of said plug shroud

a receptacle having a projection adapted to enter said slot in said plug shroud, said projection having a fiber-alignment groove therein located to receive said terminal portion of said plug fiber when said plug shroud is inserted in said receptacle, and

a receptacle door hingedly attached to said receptacle housing at said opening, having means for urging said plug door to said open position as said second end of said plug shroud is inserted into said receptacle housing.

18. The fiber optic connector of claim 17, wherein

said plug door slides sideways across said end of said plug body;

said plug door has a camming surface adapted to urge said plug door sideways; and

said receptacle door has a corresponding camming surface adapted to cam against said camming surface of said plug door upon insertion of said plug body in said receptacle.