U.S. patent application number 09/749223 was filed with the patent office on 2002-06-27 for tunable fiber optic connector and method for assembling.
Invention is credited to Nault, Patrick Jude.
Application Number | 20020081077 09/749223 |
Document ID | / |
Family ID | 25012800 |
Filed Date | 2002-06-27 |
United States Patent
Application |
20020081077 |
Kind Code |
A1 |
Nault, Patrick Jude |
June 27, 2002 |
TUNABLE FIBER OPTIC CONNECTOR AND METHOD FOR ASSEMBLING
Abstract
A tunable connector and method for assembling a tunable
connector. The connector includes a ferrule that is retainably
engaged within a hub. The connector further includes a rear housing
and a front housing. The rear housing is sized to receive and
rotationally retain the hub. The front housing has a bore that
receives and engages the exterior surface of the rear housing. The
front and rear housing include engagement members that allow the
rear housing to be retained within the front housing and rotated
relative to the front housing between discrete positions.
Inventors: |
Nault, Patrick Jude;
(Carver, MN) |
Correspondence
Address: |
MERCHANT & GOULD PC
P.O. BOX 2903
MINNEAPOLIS
MN
55402-0903
US
|
Family ID: |
25012800 |
Appl. No.: |
09/749223 |
Filed: |
December 27, 2000 |
Current U.S.
Class: |
385/78 |
Current CPC
Class: |
G02B 6/3871 20130101;
G02B 6/3843 20130101; G02B 6/266 20130101; G02B 6/3893 20130101;
G02B 6/3869 20130101; G02B 6/3821 20130101 |
Class at
Publication: |
385/78 |
International
Class: |
G02B 006/36 |
Claims
What is claimed is as follows:
1. A fiber optic connector comprising: a ferrule; a hub retainably
engaging the ferrule; a rear housing having an external surface and
a bore for receiving the hub, the rear housing rotationally
retaining the hub; a front housing having a bore with an internal
surface for receiving and engaging the external surface of the rear
housing; and an engagement member on each of the front and rear
housings, wherein the rear housing is rotatable within the front
housing between selectable discrete positions defined by the
engagement members.
2. The connector of claim 1, wherein the connector is an SC-type
connector.
3. The connector of claim 1, wherein the bore of the rear housing
has a noncircular configuration, and the hub has an external
surface with a corresponding noncircular configuration.
4. The connector of claim 3, wherein the hub inserts into the rear
housing in only one orientation.
5. The connector of claim 1, wherein the rear housing includes a
plurality of engagement members extending around a circumference of
the external surface of the rear housing, and the internal surface
of the front housing further includes a corresponding engagement
member, wherein rotation of the rear housing within the bore of the
front housing sequentially engages each of the plurality of
engagement members with the corresponding engagement member, each
sequential engagement defining a selectable discrete position.
6. The connector of claim 1, wherein the engagement member on the
rear housing includes a plurality of teeth extending from the
external surface around a circumference of the rear housing, and
wherein the engagement member on the front housing includes a
recess, the recess defined by a first tooth and a second tooth
extending from the internal surface of the front housing into the
bore of the front housing, wherein rotation of the rear housing
within the front housing sequentially engages each of the plurality
of teeth within the recess, the engagement of each of the plurality
of teeth within the recess defining a selectable discrete
position.
7. The connector of claim 6, wherein the engagement member on the
front housing further includes a second recess defined by a third
tooth and a fourth tooth extending from the internal surface of the
front housing into the bore of the front housing, the second recess
engaging one of the plurality of teeth at each of the selectable
discrete positions.
8. The connector of claim 1, wherein the front housing has a key
element, and wherein the connector further includes a grip with a
corresponding key element mating with the front housing key
element.
9. The connector of claim 8, wherein the rear housing includes a
plurality of engagement members extending around a circumference of
the external surface of the rear housing, and the internal surface
of the front housing further includes a corresponding engagement
member, wherein rotation of the rear housing within the bore of the
front housing sequentially engages each of the plurality of
engagement members with the corresponding engagement member, each
sequential engagement defining a selectable discrete position.
10. The connector of claim 8, wherein the engagement member on the
rear housing includes a plurality of teeth extending from the
external surface around a circumference of the rear housing, and
wherein the engagement member on the front housing includes a
recess, the recess defined by a first tooth and a second tooth
extending from the internal surface of the front housing into the
bore of the front housing, wherein rotation of the rear housing
within the front housing sequentially engages each of the plurality
of teeth within the recess, the engagement of each of the plurality
of teeth within the recess defining a selectable discrete
position.
11. The connector of claim 10, wherein the engagement member on the
front housing further includes a second recess defined by a third
tooth and a fourth tooth extending from the internal surface of the
front housing into the bore of the front housing, the second recess
engaging one of the plurality of teeth at each of the selectable
discrete positions.
12. The connector of claim 1, further including a grip engaging the
front housing, the grip locking the front housing to the rear
housing at one of the selectable discrete positions.
13. The connector of claim 12, wherein the rear housing includes a
plurality of engagement members extending around a circumference of
the external surface of the rear housing, and the internal surface
of the front housing further includes a corresponding engagement
member, wherein rotation of the rear housing within the bore of the
front housing sequentially engages each of the plurality of
engagement members with the corresponding engagement member, each
sequential engagement defining a selectable discrete position.
14. The connector of claim 12, wherein the engagement member on the
rear housing includes a plurality of teeth extending from the
external surface around a circumference of the rear housing, and
wherein the engagement member on the front housing includes a
recess, the recess defined by a first tooth and a second tooth
extending from the internal surface of the front housing into the
bore of the front housing, wherein rotation of the rear housing
within the front housing sequentially engages each of the plurality
of teeth within the recess, the engagement of each of the plurality
of teeth within the recess defining a selectable discrete
position.
15. The connector of claim 14, wherein the engagement member on the
front housing further includes a second recess defined by a third
tooth and a fourth tooth extending from the internal surface of the
front housing into the bore of the front housing, the second recess
engaging one of the plurality of teeth at each of the selectable
discrete positions.
16. A fiber optic connector comprising: a ferrule; a hub retainably
engaging the ferrule; a rear housing having an external surface and
a bore for rotationally retaining the hub; a front housing having a
bore with an internal surface for receiving and engaging the
external surface of the rear housing; and retention means on each
of the front and rear housings for rotationally engaging the front
housing to the rear housing at one of selectable discrete positions
defined by the retention means.
17. The connector of claim 16, wherein the connector is an SC-type
connector.
18. The connector of claim 16, wherein the retention means on the
rear housing includes a plurality of teeth extending from the
external surface around a circumference of the rear housing, and
wherein the retention means on the front housing includes a recess,
the recess defined by a first tooth and a second tooth extending
from the internal surface of the front housing into the bore of the
front housing, wherein rotation of the rear housing within the
front housing sequentially engages each of the plurality of teeth
within the recess, the engagement of each of the plurality of teeth
within the recess defining a selectable discrete position.
19. The connector of claim 18, wherein the retention means on the
front housing further includes a second recess defined by a third
tooth and a fourth tooth extending from the internal surface of the
front housing into the bore of the front housing, the second recess
engaging one of the plurality of teeth at each of the selectable
discrete positions.
20. A fiber optic connector comprising: a ferrule having a front
end and an opposite rear end; a hub retainably engaging the
ferrule; an inner housing having a first part and a second part,
wherein the hub is rotationally retained by the first part, and the
second part is rotatable relative to the first part between
selectable discrete positions, the inner housing having a front end
and a rear end, the front end of the ferrule positioned adjacent
the front end of the inner housing, the hub longitudinally movable
relative to the inner housing; a spring biasing the hub toward the
front end of the inner housing; and an outer housing engageable
with the inner housing, wherein the outer housing locks the second
part to the first part at one of the selectable discrete
positions.
21. The connector of claim 20, wherein each of the first and second
parts includes an engagement member, and wherein the selectable
discrete positions are defined by engagement between the engagement
member on the first part and the engagement member on the second
part.
22. The connector of claim 21, wherein the first part includes an
external surface and a plurality of engagement members extending
around a circumference of the external surface, and the second part
includes an internal surface having a corresponding engagement
member, wherein the first part is rotatable within the second part,
and wherein the rotation of the first part within the second part
sequentially engages each of the plurality of engagement members
with the corresponding engagement member, each sequential
engagement defining a selectable discrete position.
23. The connector of claim 21, the first part further includes an
external surface, wherein the engagement member on the first part
includes a plurality of teeth extending from the external surface
around a circumference of the first part, and wherein the
engagement member on the second part includes a recess, the recess
defined by a first tooth and a second tooth extending from an
internal surface of the second part, wherein the first part is
rotatable within the second part, and wherein rotation of the first
part within the second part sequentially engages each of the
plurality of teeth within the recess, the engagement of each of the
plurality of teeth within the recess defining a selectable discrete
position.
24. The connector of claim 23, wherein the engagement member on the
second part further includes a second recess defined by a third
tooth and a fourth tooth extending from the internal surface of the
second part, the second recess engaging one of the plurality of
teeth at each of the selectable discrete positions.
25. A method of assembling a fiber optic connector, the method
comprising the steps of: providing a ferrule extending from a hub,
the hub retainably engaging the ferrule; positioning the hub within
a bore of a rear housing to prevent rotational movement of the hub
with respect to the rear housing; inserting the rear housing into a
bore of a front housing; and rotating the rear housing within the
front housing between selectable discrete positions.
26. The method of claim 25, wherein the connector is an SC-type
connector.
27. The method of claim 25, further including the step of inserting
the front housing within a grip, wherein the grip locks the rear
housing to the front housing at one of the selectable discrete
positions.
28. The method of claim 25, wherein the rear housing includes an
external surface with a plurality of engagement members
circumferentially positioned on the external surface, and the front
housing includes a bore with a corresponding engagement member,
wherein rotating the rear housing within the bore of the front
housing sequentially engages each of the plurality of engagement
members with the corresponding engagement member, each sequential
engagement defining a selectable discrete position.
29. The method of claim 28, wherein the engagement members include
a plurality of teeth, and the corresponding engagement member on
the front housing is a recess defined by a first tooth and a second
tooth, wherein each of the plurality of teeth sequentially engages
the recess when the rear housing is rotated within the front
housing.
30. The method of claim 25, further including the step of locking
the front housing to the rear housing at one of the selectable
discrete positions.
31. The method of claim 30, wherein the rear housing includes an
external surface with a plurality of engagement members
circumferentially positioned on the external surface, and the front
housing includes a bore with a corresponding engagement member,
wherein rotating the rear housing within the bore of the front
housing sequentially engages each of the plurality of engagement
members with the corresponding engagement member, each sequential
engagement defining a selectable discrete position.
32. The method of claim 31, wherein the engagement members include
a plurality of teeth, and the corresponding engagement member on
the front housing is a recess defined by a first tooth and a second
tooth, wherein each of the plurality of teeth sequentially engages
the recess when the rear housing is rotated within the front
housing.
33. A fiber optic device comprising: a connector having a hub
retainably engaging a ferrule, a rear housing rotationally
retaining the hub, a front housing having a bore for receiving and
engaging the rear housing, and an engagement mechanism between the
front and rear housing matable in a plurality of selectable
discrete positions, wherein the rear housing is rotatable within
the bore of the front housing between the selectable discrete
positions; and a fiber optic cable connected to the connector, the
cable including a fiber extending through the connector.
34. The device of claim 33, wherein the connector is an SC-type
connector.
35. The device of claim 33, wherein the rear housing has an
external surface and a plurality of engagement members extending
around a circumference of the external surface, and the front
housing has an internal surface including a corresponding
engagement member, wherein rotation of the rear housing within the
bore of the front housing sequentially engages each of the
plurality of engagement members with the corresponding engagement
feature, each sequential engagement defining a selectable discrete
position.
36. The device of claim 35, wherein the plurality of engagement
members on the rear housing are teeth, and the corresponding
engagement member is a recess defined by a first tooth and a second
tooth, wherein rotation of the rear housing within the front
housing sequentially engages each of the plurality of teeth within
the recess, each engagement defining one of the selectable discrete
positions.
37. The device of claim 33, further including a grip engaging the
front housing, the grip locking the front housing to the rear
housing at one of the selectable discrete positions.
38. The device of claim 37, wherein the rear housing has an
external surface and a plurality of engagement members extending
around a circumference of the external surface, and the front
housing has an internal surface including a corresponding
engagement member, wherein rotation of the rear housing within the
bore of the front housing sequentially engages each of the
plurality of engagement members with the corresponding engagement
feature, each sequential engagement defining a selectable discrete
position.
39. The device of claim 38, wherein the plurality of engagement
members on the rear housing are teeth, and the corresponding
engagement member is a recess defined by a first tooth and a second
tooth, wherein rotation of the rear housing within the front
housing sequentially engages each of the plurality of teeth within
the recess, each engagement defining one of the selectable discrete
positions.
Description
FIELD OF THE INVENTION
[0001] The present invention relates to tunable fiber optic
connectors for use in optical fiber signal transmission systems,
and to methods for assembling such fiber optic connectors.
BACKGROUND OF THE INVENTION
[0002] Fiber optic cables are used in the telecommunication
industry to transmit light signals in high speed data and
communication systems. A standard fiber optic cable includes a
fiber with an inner light transmitting optical core. Surrounding
the fiber typically is a reinforcing layer and an outer protective
casing.
[0003] A fiber terminates at a fiber optic connector. Connectors
are frequently used to non-permanently connect and disconnect
optical elements in a fiber optic transmission system. There are
many different fiber optic connector types. Some of the more common
connectors are FC and SC connectors. Other types of connectors
include ST and D4-type connectors.
[0004] A typical SC fiber optic connector includes a housing having
a front end positioned opposite from a rear end. The front end of
the SC connector housing is commonly configured to be inserted
within an adapter. An example adapter is shown in U.S. Pat. No.
5,317,663, the disclosure of which is incorporated by reference.
The SC connector typically further includes a ferrule that is
positioned within the front and rear ends of the housing, and
adjacent the front end. The ferrule is axially moveable relative to
the housing, and is spring biased toward the front of the
connector. The fiber optic cable has an end that is stripped. The
stripped end includes a bare fiber that extends into the connector
and through the ferrule.
[0005] A connector, such as the connector described above, is mated
to another connector within an adapter like the adapter of U.S.
Pat. No. 5,317,663. A first connector is received within the front
portion of the adapter, and a second fiber is received within the
rear portion of the adapter. When two connectors are fully received
within an adapter, the ferrules (and hence the fibers internal to
the ferrule) contact or are in close proximity to each other to
provide for signal transmission between the fibers.
[0006] Signal losses within a system often occur within the
connection between two optical fiber cores. Due to manufacturing
tolerances of the ferrule outer diameter to inner diameter
concentricity, ferrule inner diameter hole size and fiber outer
diameter, and fiber core to fiber outer diameter concentricity,
when the fiber is inserted into the ferrule the core of a fiber may
not and typically does not end up perfectly centered relative to
the ferrule outer diameter. If one or both of the fibers are off
center, when they are connected within an adapter, the fibers will
not be aligned and thus there will be a signal loss when the signal
is transmitted between the two fibers. It is therefore desirable to
have a tunable connector that can provide for optimal alignment
with another connector so as to minimize signal loss.
SUMMARY OF THE INVENTION
[0007] One aspect of the present invention relates to a fiber optic
connector. The connector includes a ferrule that is retainably
engaged within a hub. The connector further includes a rear housing
and a front housing. The rear housing is sized to receive and
rotationally retain the hub. The front housing has a bore that
receives and engages the exterior surface of the rear housing. The
front and rear housing include engagement members that allow the
rear housing to be retained within the front housing and rotated
relative to the front housing between discrete positions.
[0008] Another aspect of the present invention relates to a method
for assembling a fiber optic connector. The method includes
providing a ferrule retainably engaging a hub. This assembly is
then positioned within the bore of a rear housing with the hub
rotationally retained within the bore. Next, the rear housing is
inserted into the bore of a front housing, and the rear housing is
then rotated within the front housing between discrete
positions.
[0009] A variety of advantages of the invention will be set forth
in part in the description that follows, and in part will be
apparent from the description, or may be learned by practicing the
invention. It is to be understood that both the foregoing general
description and the following detailed description are explanatory
only and are not restrictive of the invention as claimed.
BRIEF DESCRIPTION OF THE DRAWINGS
[0010] The accompanying drawings, which are incorporated in and
constitute a part of the specification, illustrate several aspects
of the invention and together with the description, serve to
explain the principles of the invention. A brief description of the
drawings is as follows:
[0011] FIG. 1 is a side view of an SC-type connector constructed in
accordance with the principles of the present invention without the
grip;
[0012] FIG. 2 is a partial cross-sectional side view taken
longitudinally through the connector of FIG. 1 between line 2-2
without the boot;
[0013] FIG. 3 is a cross-sectional side view of the connector of
FIG. 1 fully assembled including the grip mounted over the front of
the connector and a fiber optic cable attached to the
connector;
[0014] FIG. 4 is a cross-sectional side view of the fully assembled
connector shown in FIG. 3 rotated 90 degrees to a second
orientation about the longitudinal axis;
[0015] FIG. 5 is a cross-sectional end view taken along line 5-5 in
FIG. 4;
[0016] FIG. 6 is a further cross-sectional end view taken along
line 6-6 in FIG. 4;
[0017] FIG. 7 is an exploded perspective view of the SC-type
connector of the present invention;
[0018] FIG. 8 is a cross-sectional side view of the hub with
connected ferrule used in the SC-type connector of the present
invention;
[0019] FIG. 9 is a cross-sectional side view of the front housing
piece of the SC-type connector of the present invention; and
[0020] FIG. 10 is an enlarged cross-sectional side view showing a
portion of the collar on the rear housing piece of the SC-type
connector engaging one of the slots in the front housing piece.
DETAILED DESCRIPTION
[0021] Reference will now be made in detail to exemplary aspects of
the present invention that are illustrated in the accompanying
drawings. Where ever possible, the same reference numbers will be
used throughout the drawings to refer to the same or like
parts.
[0022] FIG. 1 illustrates an SC-type connector 20 constructed in
accordance with the principles of the present invention. The
connector 20 includes a housing 22 having a front housing 24 that
connects to a rear housing 26. A boot 28 is mounted at the rear end
23 of the connector 20. The front portion 49 of a ferrule 48 is
shown extending out the front end 25 of the connector 20. The
ferrule 48 is mounted to a hub 44 (not shown in FIG. 1) which
together are slidably mounted within the connector 20. As shown,
the rear housing 26 is a unitary piece. However, it could
alternatively be a constructed of more than one piece such as the
two-piece construction shown and described in pending application
Ser. No. 09/459,968, filed Dec. 13, 1999, the disclosure of which
is expressly incorporated by reference herein.
[0023] For clarity, no fiber optic cable is shown in FIG. 1. Also
for clarity, FIG. 1 does not include the slidable outer grip
located at the front of the housing that is typically found on an
SC-type connector. However, the grip and the cable are shown on
other figures and will be described later in the specification in
connection with the description of those other figures.
[0024] Referring to FIG. 2, the front housing 24 of the connector
20 extends along a longitudinal axis 30 and includes a front end 32
positioned opposite from a rear end 34. The front housing 24 also
defines a front chamber 36 and a rear chamber 38. A transverse wall
40 separates the front and rear chambers 36 and 38. An opening 42
centered about the longitudinal axis 30 is defined by the
transverse wall 40. The front and rear ends 32 and 34 of the front
housing piece 24 are open with a bore 33 (see FIG. 4) formed
therebetween extending along longitudinal axis 30.
[0025] The connector 20 also includes a hub 44 positioned within
the connector 20. The hub 44 is mounted to slide longitudinally
along the axis 30 relative to the front housing piece 24. The hub
44 has openings 45 and 47 at its front and rear portions 55 and 57
with a bore 53 extending between the openings.
[0026] The hub 44 secures a ferrule 48. The ferrule 48 includes a
rear portion 51 mounted within the front opening 45 defined by the
hub 44. The ferrule 48 may be secured to the hub 44 using a
conventional fastening technique, such as an epoxy adhesive. The
hub 44 can also be mounted to the ferrule 48 with an interference
fit or it can be molded around the ferrule 48. The ferrule 48
includes a bore 59 for receiving a bare optical fiber. The ferrule
48 extends along the longitudinal axis 30 from the hub 44 toward
the front end 32 of the front housing piece 24. The ferrule 48
extends through the central opening 42 of the transverse wall 40
between the front and rear chambers 36 and 38 of the front housing
piece 24, and protrudes out from the front end 23 of the connector
20.
[0027] The connector 20 further includes a coil spring 56
positioned within the rear chamber 38. The coil spring 56 surrounds
the rear portion 57 of the hub 44 and is captured between a
forwardly facing shoulder 58 formed by the rear housing piece 26
and a rearwardly facing shoulder 60 formed by the hub 44. The
spring 56 functions to bias the hub 44 toward the front end 32 of
the front housing piece 24. Because the ferrule 48 is connected to
the hub 44, the spring 56 also functions to bias the ferrule 48 in
a forward direction.
[0028] The rear housing 26 also extends along longitudinal axis 30
and includes a front end 62 positioned opposite from a rear end 64.
The hub 44 and surrounding spring 56 slide into the opening 27 at
the front end 62 of the rear housing 26. The hub 44 and spring 56,
however, are not mechanically fastened to the rear housing 26, and
thus are free to move longitudinally along axis 30 with respect to
the rear housing 26. The only limit placed on the rearward movement
of the hub 44 and spring 56 into the rear housing 26 is the forward
facing shoulder 58 on the rear housing 26 which, as mentioned
above, engages the spring 56. The engagement of the spring 56 to
the shoulder 58 functions to bias the hub 44 and connected ferrule
48 outward from the opening 27 at the front end 62 of the rear
housing 26.
[0029] The front portion 55 of the hub 44 and the opening 27 at the
front end 62 of the rear housing 26 are sized so that the hub 44,
when received within the rear housing 26, cannot be rotated within
the rear housing 26. Likewise, the ferrule 48, which is secured to
the hub 44, does not rotate relative to the rear housing 26 when
the hub 44 is fully inserted therein. This can be achieved by
having a non-circularly shaped hub 44 and a corresponding
non-circularly shaped opening 27 at the front end 62 of the rear
housing 26. In the embodiment shown, the hub 44 and the opening 27
to the rear housing 26 have the same non-noncircular shape so that
the hub 44 can only be received within the opening 27 in one
orientation. As shown in FIG. 7, the outer circumference of the hub
44 and opening in the rear housing 26 are each defined by three
planar sides 100 and an arched side 103. This configuration permits
the hub 44 to be received within the rear housing 26 in only one
orientation, and once received within the opening, the hub 44 (and
ferrule 48) is not rotatable relative to the rear housing 26. It
can be appreciated that other configurations could be used which
allow the hub 44 to be inserted into the rear housing 26 in
multiple orientations but not be rotatable once the hub 44 is
received within the rear housing 26.
[0030] Further details of the front housing 24 can be seen in FIGS.
7 and 9. The rear portion 34 of the front housing 24 includes two
extensions 66 and 68 that define the opening 29 at the rear portion
34. The extensions 66 and 68 also define two tapered cut-outs 70
that extend longitudinally toward the front end 32 of the front
housing 24 on two of the sides of the front housing 24 (see FIG. 7
showing one of the tapered cut-outs 70 on the top-facing side of
the front housing 24). The cut-outs 70 give the extensions 66 and
68 a resiliency allowing them to be deflected outward when suitable
pressure is applied from within the opening 29. On the inside of
each of the resilient extensions 66 and 68 proximate the opening 29
at the rear end 34 are a pair of projections, or teeth 74 and 76,
extending into the bore 33 of the front housing 24 (see FIG. 5).
Each of the pairs of teeth 74 and 76 defines a recess 78
therebetween. Adjacent the pairs of teeth 74 and 76 are slots 80
formed within the resilient extensions 66 and 68.
[0031] As noted above, the front housing 24 connects to the rear
housing 26. The front end 62 of rear housing 26 is received into
the opening 29 at the rear end 34 of the front housing 24. A collar
82 extends around the external surface of the rear housing 26. When
the rear housing 26 is inserted into the opening 29 of the front
housing 24, the collar 82 presses up against the pairs of teeth 74
and 76 that project into the bore 33 of the front housing 24,
inhibiting further insertion of the rear housing 26 into the front
housing 24. However, when added longitudinal pressure is applied by
the rear housing 26 against the front housing 24, the resilient
extensions 66 and 68 are deflected outward which increases the
opening 29 slightly to allow the collar 82 to pass over the pairs
of teeth 74 and 76. Immediately after passing over the two pairs of
teeth 74 and 76, the collar 82 snaps into the adjacent slots 80
formed in the front housing 24. When that occurs, the resilient
extensions 66 and 68 quickly return to their natural positions,
which secures the rear housing 26 to the front housing 24. FIG. 10
shows a cross-sectional view of the collar 82 retained within one
of the slots 80. Forward and backward facing shoulders 86 and 88 on
the front housing 24, which define the slot 80, prevent
longitudinal movement of the mounted rear housing 26 relative to
the front housing 24 when the collar 82 is positioned within the
slots 80.
[0032] The front and rear housings 24 and 26 further include
structure that inhibits rotational movement of the rear housing 26
when it is snapped into the front housing 24. Adjacent the collar
82 on the rear housing 26 is a ring of projections, or teeth 90,
that extend outward around the circumference of the rear housing
26. The exemplary embodiment shown includes twelve evenly spaced
teeth 90 formed around the circumference of the rear housing 26.
These projections 90 are seen most clearly in FIGS. 5 and 7. When
the collar 82 snaps into the slots 80 on the front housing 24, as
described above, the ring of teeth 90 on the external surface of
the rear housing 26 at the same time engages and is aligned with
the pairs of internally projecting teeth 74 and 76 within the bore
33 of the front housing 24. Each of the teeth 90 on the rear
housing 26 are sized to be received within the recesses 78 formed
between the pairs of teeth 74 and 76. As such when the rear housing
26 is snapped into the front housing 24, two of the teeth 90 on
directly opposite sides are forced into the recesses 78 formed on
the opposing resilient extensions 66 and 68 of the front housing
24. This engagement is shown in FIG. 5. With this arrangement, the
rear housing 26 is not freely rotatable within the front housing
24, but is held at a discrete position. However, if the rear
housing 26 is twisted relative to the front housing 24 with
sufficient rotational pressure, the resilient extensions 66 and 68
will deflect outward slightly, allowing the rear housing 26 to be
rotated within the front housing 24 to a second position with a new
set of opposing teeth 90 on the rear housing 26 engaging the
recesses 78. Because there are twelve different teeth 90 on the
rear housing 26 in the exemplary embodiment, there are twelve
different discrete rotational positions that can be selected when
rotationally positioning the rear housing 26 within the front
housing 24. It is understood that the number and configuration of
the projections on the front and rear housings 24 and 26 could be
altered without departing from the scope of the present invention.
Other structure for providing the selection of discrete rotational
positions of the inserted rear housing 26 with respect to the front
housing 24 could also be used that are consistent with the
teachings of this invention.
[0033] The connector 20 further includes a grip 92. The connector
housing 22 inserts into a bore 93 formed within the grip 92. The
front housing 24 includes structure that mounts the connector
housing 22 within the grip 92. When the connector housing 22 is
positioned within the grip 92, the grip 92 restrains the resilient
extensions 66 and 68, preventing them from deflecting outward. As
such, rotational alignment between the front and rear housings 24
and 26, via the interlocking teeth on the housings, cannot be
further altered once the grip 92 is positioned over the connector
housing 22. The external surface of the connector housing 22 and
the bore 93 of the grip 92 are configured such that the connector
housing 22 can be fully inserted into the grip 92 in only one
orientation. Alternatively, the connector housing 22 could include
other types of external keys. The external surface of the grip 92
includes a key 94 (seen in FIGS. 4 and 7) that is sized to be
received into a slot of an adaptor (not shown), such as the adapter
of U.S. Pat. No. 5,317,663, where the connector mates with a second
SC-type connector. As described in the method of assembly below,
with this configuration, prior to locking the rotational
orientation of the connector housing 22, the connector 20 can be
tuned and the front and rear housings 24 and 26 rotated relative to
one another to align with a key on the connector housing 22.
[0034] The present invention is further directed to a method for
assembling the SC-type connector described above. The ferrule 48 is
first mounted within the opening 45 formed in the front portion 55
of the hub 44. A cross-sectional side viewing of this arrangement
is shown in FIG. 8. The spring 56 is then positioned over the rear
portion 57 of the hub 44, and together these are inserted into the
front end 62 of the rear housing 26. As mentioned above, the front
portion 55 of the hub 44 is sized so that when it is inserted into
the rear housing 26 the hub 44 (and connected ferrule 48) cannot
rotate relative to the rear housing 26.
[0035] Next, the rear housing 26 is snapped into the front housing
24, thereby retaining the hub 44 and ferrule 48 (and spring 56)
within the connected housing 22. This connection is made to prevent
longitudinal movement of the rear housing 26 relative to the front
housing 24. However, the engagement does not prevent rotational
movement between the two housings 24 and 26.
[0036] At this point, a fiber optic cable 96, having a central
fiber 98, is attached to the connector 20 using conventional
techniques well known in the art. This includes stripping the end
of the cable 96 to expose the fiber 98. The fiber 98 is then fed
into the connector 20 all the way through the bore 59 in the
ferrule 48. The fiber may be either mechanically or adhesively
retained within the ferrule 48. A reinforcement layer of the fiber
optic cable 96 is crimped with a crimp sleeve 71. The boot 28 is
positioned over the crimp 71 and helps provide strain relief. The
exposed bare fiber at the front end 49 of the ferrule 48 may then
be polished.
[0037] The connector 20 is then tuned. This includes measuring the
eccentricity with appropriate test equipment to identify, for
example, any offset of the optical core within the fiber 98 or
offset of the fiber 98 within the ferrule 48. After determining the
direction of any such offset, the rear housing 26 is rotated within
the front housing 24 to one of the selectable discrete positions.
Those positions are defined by the rotational positions of the
projections 90 on the external surface of the rear housing 26 that
engage a corresponding alignment feature, such as a recess 78
between a pair of projections (e.g., pairs of teeth 74 and 76), on
the internal surface of the front housing 24. A position is
selected that will minimize signal loss when the connector 20 is
mated with another connector within an adaptor. As mentioned, the
front housing 24 has a shape that permits insertion of it into a
grip 92 in only one orientation. As shown in FIG. 6, the grip 92
includes tabs 95 and 97 that block access of the connector housing
22 into the grip 92 if the housing 22 is improperly orientated.
Thus, the discrete position is selected to align with the
orientation in which the connector 20 is to be inserted within the
grip 92. In this way, the configuration of the housing serves as a
key to which the selectable discrete position is aligned. Other
alternative keys could be included on the housing to align with the
selectable discrete position.
[0038] Finally, once the proper rotational position is selected,
connector 20 is inserted within a grip 92. The grip 92 prevents the
extensions 66 and 68 from deflecting outward, and thus rotationally
locks the rear housing 26 to the front housing 24 at the
previously-selected discrete position. The connector 20 can then be
inserted into an adaptor (not shown) for mating with a second
SC-type connector.
[0039] With regard to the foregoing description, it is to be
understood that changes may be made in detail, especially in
matters of the construction materials employed and the shape, size
and arrangement of the parts without departing from the scope of
the present invention. It is intended that the specification and
depicted aspects be considered exemplary only, with a true scope
and spirit of the invention being indicated by the broad meaning of
the following claims.
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