OPTICAL FIBER CONNECTOR AND FERRULE

• US 20150331201A1
• Filed: 05/13/2014
• Published: 11/19/2015
• Est. Priority Date: 05/13/2014
• Status: Active Grant

• Current Assignee: SENKO Advanced Components, Inc. (SENKO Group Holdings Co., Ltd.)
• Original Assignee: SENKO Advanced Components, Inc. (SENKO Group Holdings Co., Ltd.)
• Inventors: CHANG, Jimmy Jun-Fu, TAKANO, Kazuyoshi
• Granted Patent: US 9,274,287 B2
• Time in Patent Office: Days
• US Class Current: 1/1
• CPC Class Codes: G02B 6/38 having fibre to fibre mating means
• CPC Class Codes: G02B 6/3807 Dismountable connectors, i.e. comprising plugs
• CPC Class Codes: G02B 6/3821 with axial spring biasing or loading means G02B6/3847 takes precedence
• CPC Class Codes: G02B 6/3825 with an intermediate part, e.g. adapter, receptacle, linking two plugs
• CPC Class Codes: G02B 6/3829 Bent or angled connectors G02B6/3827 takes precedence
• 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 6/3851 Ferrules having keying or coding means
• CPC Class Codes: G02B 6/3871 Ferrule rotatable with respect to plug body, e.g. for setting rotational position adjusting fibre within the ferrule, G02B6/3843; Fixation of ferrules after rotation
• CPC Class Codes: G02B 6/3873 Connectors using guide surfaces for aligning ferrule ends, e.g. tubes, sleeves, V-grooves, rods, pins, balls
• CPC Class Codes: G02B 6/3875 Floatingly supported sleeves
• CPC Class Codes: G02B 6/3882 using rods, pins or balls to align a pair of ferrule ends
• CPC Class Codes: G02B 6/3883 using rods, pins or balls to align a plurality of pairs of ferrule ends
• 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 6/389 characterised by the method of fastening connecting plugs and sockets, e.g. screw- or nut-lock, snap-in, bayonet type

Abstract

Multi-fiber ferrules may be produced with tapered bodies and guide pin holes that have fluted internal surfaces with projections for engaging the guide pins, and channels for capturing any foreign material that may accumulate on or around the guide pins, thereby providing improved consistency in fiber connections during mating of the ferrules.

Claims

1. An optical fiber connector configured for being coupled with an adapter to mate with another optical fiber connector, the connector comprising:

a housing comprising a first end for being coupled with the adapter, the housing defining a first longitudinal passage therethrough, the first longitudinal passage defining a first longitudinal axis;

a ferrule floatably mounted at the first housing end within the first longitudinal passage for relative movement between the ferrule and the housing, the ferrule comprising;

a first end protruding forward of the first housing end, and a second end spaced from the first end and disposed within the first longitudinal passage, the ferrule defining a second longitudinal axis extending from the first end to the second end, and the first end comprises an end face for mating with an end face of an additional ferrule;

at least first and second alignment pin holes in the end face configured for receiving an alignment pin therein, each of the first and second alignment pin holes having a longitudinal direction parallel with the second longitudinal axis, and each pin hole defining an interior surface comprising a plurality of spaced apart longitudinal grooves extending from the end face and into the ferrule; and

at least one side wall having a first wall end at the end face and extending from the end face to a second wall end adjacent the second end of the ferrule, the at least one side wall tapering outwardly away from the second longitudinal axis in a direction from the end face towards the second end so that the ferrule is tiltable within the housing passage to offset the second longitudinal axis with respect to the first longitudinal axis.

2. The connector of claim 1, wherein the interior surface within each of the first and second alignment pin holes comprises at least three longitudinal ridges spaced substantially equidistantly and circumferentially from one another about the internal circumference of the pin holes and separated from one another by one of the plurality of longitudinal grooves, with each of the at least three longitudinal ridges defining an interior surface for contacting an alignment pin to be disposed within the pin hole.

3. The connector of claim 2, wherein the interior surface within each of the first and second alignment pin holes comprises at least three longitudinal ridges spaced at about 120°

from one another about the internal circumference of the pin holes, with the longitudinal ridges extending in a circumferential direction at most about 60°

along the internal circumference of the pin holes, and the longitudinal grooves disposed between the longitudinal ridges extend at least about 60°

along the internal circumference of the pin holes.

4. The connector of claim 2, wherein the at least one side wall comprises a first side wall, a second side wall, a third side wall and a fourth side wall disposed about the second longitudinal axis and each extending from a first wall end at the end face to a second wall end adjacent the second end of the ferrule, wherein the first side wall and the third side wall are disposed opposite one another and the second side wall and the fourth side wall are disposed opposite one another and orthogonal to the first side wall and the third side, and each side wall is independently disposed at a taper angle with respect to the second longitudinal axis.

5. The connector of claim 4, wherein:

the first side wall, the second side wall, the third side wall and the fourth side wall define a rectangular frustum having a first cross-sectional area defining the end face and a second cross-sectional area at the second wall ends, wherein the second cross-sectional area is greater than the first cross-sectional area;

each of the first side wall, the second side wall, the third side wall, and the fourth side wall are disposed at the same taper angle with respect to the longitudinal axis; and

the ferrule is tiltable within the first longitudinal passage of the housing through a conical deflection about the first longitudinal axis to offset the second longitudinal axis with respect to the first longitudinal axis by an amount of at least the taper angle.

6. The connector of claim 5, wherein:

the second end of the ferrule comprises a flange adjacent the second wall ends, the flange extending laterally away from the second walls ends to define a peripheral shoulder adjacent the second wall ends, the flange defining a third cross-sectional area greater than the second cross-sectional area;

the housing passage comprises a first passage portion at the first housing end and a second passage portion adjacent the first passage portion, wherein;

the first passage portion comprises an interior surface disposed about at least a portion of the ferrule, the interior surface comprising a first surface adjacent the first side wall, a second surface adjacent the second side wall, a third surface adjacent the third side wall, and a fourth surface adjacent the fourth side wall, with the first surface, the second surface, the third surface and the fourth surface each parallel to the first longitudinal axis;

the first side wall, the second side wall, the third side wall and the fourth side wall define a rectangular passage having a shape corresponding to the second cross-sectional area of the ferrule, and the first passage portion has a cross-sectional area greater than the second cross sectional area and less than the third cross-sectional area; and

the second passage portion has a cross-sectional area greater than the third cross-sectional area to define an internal shoulder extending around the interior surface between the first passage portion and the second passage portion; and

the ferrule fits within the housing passage with the first end of the ferrule extending through the first passage portion and the ferrule flange in the second passage portion; and

the connector further comprises a biasing device for biasing the peripheral shoulder of the ferrule flange into engagement with the internal shoulder.

7. The connector of claim 6, wherein at least one of the peripheral shoulder of the ferrule flange and the internal shoulder of the passage comprises a beveled corner for engaging the other of the internal shoulder and the peripheral shoulder for centering the ferrule within the first passage portion under bias of the biasing device.

8. The connector of claim 7, wherein:

the connector is an MPO connector;

the ferrule comprises an MT ferrule;

the taper angle is about 3°

; and

the interior surface within each of the first and second alignment pin holes comprises at least three longitudinal ridges spaced at about 120°

from one another about the internal circumference of the pin holes, with the longitudinal ridges extending in a circumferential direction at most about 60°

along the internal circumference of the pin holes, and the longitudinal grooves disposed between the longitudinal ridges extend at least about 60°

along the internal circumference of the pin holes.

9. An optical ferrule comprising:

a housing, the housing comprising;

a first end, a second end spaced from the first end, and a longitudinal axis extending from the first end to the second end, wherein the first end comprises an end face for mating with an end face of an additional optical ferrule;

at least one passage extending through the housing and configured for receiving at least one optical fiber therein for termination of the at least one optical fiber at the end face; and

at least one side wall extending from the end face towards the second end, the at least one side wall tapering outwardly away from the longitudinal axis in a direction from the first end to the second end.

10. The ferrule of claim 9, wherein the at least one side wall comprises a plurality of side walls disposed about the longitudinal axis and extending from the end face towards the second end, and each of the side walls tapers outwardly away from the second longitudinal axis in the direction from the end face towards the second end.

11. The ferrule of claim 9, wherein the at least one side wall comprises a first side wall, a second side wall, a third side wall and a fourth side wall disposed about the longitudinal axis and each extending from a first wall end at the end face to a second wall end adjacent the second end of the ferrule, wherein the first side wall and the third side wall are disposed opposite one another, the second side wall and the fourth side wall are disposed opposite one another and orthogonal to the first side wall and the third side, and each side wall is independently disposed at a taper angle with respect to the longitudinal axis.

12. The ferrule of claim 11, wherein the first side wall, the second side wall, the third side wall and the fourth side wall define a rectangular frustum having a first cross-sectional area defining the end face and a second cross-sectional area at the second wall ends, wherein the second cross-sectional area is greater than the first cross-sectional area.

13. The ferrule of claim 12, wherein each of the first side wall, the second side wall, the third side wall, and the fourth side wall are disposed at the same taper angle with respect to the longitudinal axis.

14. The ferrule of claim 13, wherein:

the optical ferrule comprises an MT ferrule;

the taper angle is about 3°

;

the ferrule housing additionally comprises at least first and second alignment pin holes extending through the housing from the end face to the second end, and configured for receiving an alignment pin therein, each of the first and second alignment pin holes having a longitudinal direction parallel with the longitudinal axis, and each pin hole defining an interior surface comprising a plurality of spaced apart longitudinal grooves extending from the end face;

the second end of the ferrule comprises a flange adjacent the second wall ends, the flange extending laterally away from the longitudinal axis and second walls ends to define a peripheral shoulder adjacent the second wall ends, the flange defining a third cross-sectional area greater than the second cross-sectional area; and

the peripheral shoulder comprises a beveled corner.

15. An optical ferrule comprising:

a housing, the housing comprising;

a first end, a second end spaced from the first end, and a longitudinal axis extending from the first end to the second end, wherein the first end comprises an end face for mating with an end face of an additional optical ferrule;

at least one passage extending through the housing and configured for receiving at least one optical fiber therein for termination of the at least one optical fiber at the end face; and

at least first and second alignment pin holes in the end face configured for receiving an alignment pin therein, each of the first and second alignment pin holes having a longitudinal direction parallel with the longitudinal axis, and defining an interior surface comprising a plurality of spaced apart longitudinal grooves extending from the end face and into the housing.

16. The optical ferrule of claim 15, wherein the interior surface within each of the first and second alignment pin holes comprises at least two longitudinal ridges spaced circumferentially from one another about the internal circumference of the pin holes, and separated from one another by one of the plurality of longitudinal grooves, with each of the at least two longitudinal ridges defining an interior surface for contacting an alignment pin to be disposed within the pin hole.

17. The optical ferrule of claim 16, wherein:

the interior surface for contacting an alignment pin define a first internal diameter within the pin hole and the longitudinal grooves have a base defining a second internal diameter within the pin hole;

the second internal diameter is greater than the first internal diameter; and

the first internal diameter corresponds to a diameter of an alignment pin to be disposed within the pin hole.

18. The optical ferrule of claim 17, wherein:

the pin holes have n longitudinal ridges separated by n longitudinal grooves;

the n longitudinal ridges are disposed equidistantly from one another on the interior surface and spaced at 360°

/n from one another along the internal circumference of pin hole, and each ridge extends in a circumferential direction at most about 360°

/2n along the internal circumference of the pin holes; and

the n longitudinal grooves are disposed equidistantly from one another on the interior surface and spaced at 360°

/n from one another along the internal circumference of pin hole, and each groove extends in a circumferential direction at least about 360°

/2n along the internal circumference of the pin holes.

19. The optical ferrule of claim 18, wherein:

the optical ferrule is configured to be mated with an additional optical ferrule with the end face of the optical ferrule in face-to-face contact with the end face of the additional optical ferrule; and

the longitudinal ridges and longitudinal grooves within each pin hole of the optical ferrule are configured so that when mated, the longitudinal ridges of the optical ferrule are aligned with the longitudinal grooves of the additional optical ferrule, and the longitudinal grooves of the optical ferrule are aligned with the longitudinal ridges of the additional optical ferrule.

20. The optical ferrule of claim 19, wherein:

the optical ferrule comprises an MT ferrule;

n is three;

the longitudinal ridges are disposed at about 120°

from one another and extend in a circumferential direction at most about 60°

along the internal circumference of the pin holes;

the longitudinal grooves disposed between the longitudinal ridges extend at least about 60°

along the internal circumference of the pin holes;

the housing further comprises a first side wall, a second side wall, a third side wall and a fourth side wall disposed about the second longitudinal axis and each extending from a first wall end at the end face to a second wall end adjacent the second end, wherein the first side wall and the third side wall are disposed opposite one another and the second side wall and the fourth side wall are disposed opposite one another and orthogonal to the first side wall and the third side, and each side wall is disposed at a taper angle of about 3°

with respect to the second longitudinal axis;

the pin holes are disposed adjacent the second and fourth side walls and have a top disposed towards the first side wall and a bottom disposed towards the third side wall; and

each pin hole has one of the three grooves at the top and one of the three ridges at the bottom.