Note: Descriptions are shown in the official language in which they were submitted.
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CHIMPED CONI~CTO~ ASSEMBLY FOR
FI~ER OPTIC CABLES OR ~HE LIKE
TECHNICAL FIELD
The present invention relates generally to ~iber
optics and~ more particularly, to a fiber optic connector
a~sembly for a fiber optlc cable havlng one or more single
optical fiber~ thereln,
BACKGROO~ OF ART
Fiber ~tlc cables generally include one or more
10 s~ngle optical fibers and are generally ~raglle in
na~ure ln contrast to electrical cables. Crimplng has
been widel~ accepted a~ one method o~ terminatln~ an
electrical cable to a contact or to a connector assembly
becaùse o~ the rel~abillty of this type o~ termlnat~on
15 as well a~ the lnexpensive nature o~ the ~rimping opera~
tlon itsel~. For these reasons, it is hlghly de irable
to provide ~or cr~mping o~ ~iber optic cables for term-
ination to contacts or conr.ector assemblies. The differ~
ence, with regards to crimping, between flber optic
20 cables and electrical cables is that in an electrlcal
cable the contact or the connector assembly 1~ directly
crimped to the conductor itself. In a fiber optic
cable, the crimplng is done to one or mora strength
members which usually surro~nd the optical flbers on the
25 inside or outside o~ a ~aaket o~ the cable. This re-
qulre3 the addition of a separate component, namely a
crlmp~ng ferrule, ~or crimp~ng the strength member
between the ~errule and a body member of the co~tact or
connector as~embly ~o that the one or more single opti~
30 cal ~ibers o~ the fiber opt~a cable are not over-stressed
or damaged durlng termîn~tlon or during handllng o~ the
~lber optic cable a~ter it has been ~ssembled ~o the
connector. This in~ention provides an improved crlmping
means in the ~orm o~ a connector assemhly which increases
35 the crimping diameters between the ~errule member and
the connector body while also accommodating the add~t~onal
thickne~s or the ~errulP member permittlng sealing and
enhancing fleld termination
~RIEF SUMMARY OF THE IN~ENTION
Accord~ngly, a princ~pal ob~ect o~ the present
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invention is to provide a new and improved connector ;Issem~ly
for one or more single optical fibers of a fiber optic cable or
the like which has one or more strength members therein.
Another object of the invention is to provide a new
; and improved connector assembly for fixing ~he relationship
between the strength members of a fiber optic cable and the fiLer
optic contacts terminated to the fibers thereof so that the ter-
minated fibers can be readily assembled to the connector assembly
without over-stressing the fibers.
A further object of the invention is to provide a
connector assembly of the character described which increases
the number of crimping diameters between the connector body of
the connector assembly and the ferrule member without increasing
the dimensions thereof.
` Still another object of the invention is to provide a
connector assembly of the character described which accommodates
the additional thickness of the ferrule member to provide a uni-
formly dimensioned assembly for field termination.
ln the embodiment of the invention disclosed herein,
a connector assembly is disclosed for one or more single optical
fibers of a fiber optic cable or the like which has a strength
; member therein. A connector body is provided for receiving the
one or more single optical fibers of the fiber optic cable. The
connector body has a rear end portion over which the strengtll
member of the fiber optic cable is positionable. The rear end
portion of the connector body is provided with one or more
annular crimp receiving grooves. A ferrule member is position-
- able over the grooved rear end portion of the connector body for
crimping the strength member between the ferrule member alld thc
grooved rear end portion of the connector body. The err-l1e
member is crimped to have one OT more ribs nested in the grooves ~ ~ of the connector bodyO Each of the grooves cooperates with OIIC
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of the ribs to provide a plurality of crimping di~meters there-
between.
The grooves on the connector body are generally V-
shaped as are the ribs on the ferrule member. The included anglc
of each of the V-shaped grooves is smaller than that of the V~
shaped ribs of the ferrule member so as to increase or double
the number of crimping diameters between the connector body and -
the ferrule member, namely along the edges of the grooves.
The connector body has a larger diameter portion
adjacent a smaller diameter rear end portion, the latter being
provided with the generally V-shaped grooves. The outside
diameter of the ferrule member is substantially the same as
that of the larger diameter portion of the connector body so as
to be generally flush therewith.
In one form of the invention, the fiber optic cable
has an inner jacket surro~nding the one or more single optical
fibers, with the strength member surrounding the inner jacket and
extending beyond the jacket. The rear end portion of the con-
nector body has a transverse abutment surface for engaging the
end of the jacket providing an interface between the cable and
the connector body. The ferrule member has a second crimping
portion for crimping onto the outside of the strength member
rearwardly of the interface between the-inner jacket and the
connector body. The cable has a second or outer jacket surroun~-
ing the strength member, and the rear end of the ferrule membcr
is provided with a transverse abutment surface for engaging thc
end of the outer jacket of the cable providing a second inter-
face between the cable and the connector assembly.
In another embodiment of the invention, the fiber
optic cable has a jacket surrounding both the strength membcr
and the one or more single optical fibers of the fiber optic
cable, and the ferrule member has a second crimping portion for
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crimping onto the outside of the jacket of the cable.
Other objects, features and advantages of the invcn-
tion will be apparent from the following detailed description
taken in conjunction with the accompanying drawings.
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~RIEF D~SCRIPTION 0~ THE DRAWIN~S
Figure 1 is a ~ragmented perspective vie~ o~
the connector assembly o~ the present lnvention ter-
minated to a ~iber opt~c cableg
Figure 2 is a ~ragmented vertical sectional view~
on an enlarged scale, o~ the connector assembly of the
present inventlon, terminated to the end of one form o~
a ~iber optlc cable~
Figure 3 ~s a view slmilar to that of Flgure 2
wlth the connector assembl~ o~ th0 present lnvention
terminated to the end o~ another ~orm o~ fiber optic
cable;
Flgure ~ is an enlarged, somewhat schematic
sectlonal view through a single crimp receiving groove
o~ the connec~or body and an al~gned crimping rlb o~ the
ferrule member of the connector assembly o~ the present
inventlon; ancl
Figure 5 ls a vertical sectlonal view of a split
die set ~or crlmping the connector assembly o~ the
present lnvention onto a flber optic cable.
DETAILED DESCRIPTION OF THE INVENTION
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Referring to the drawll~gs in greater deta~l, a
connector assembly ~n accordance with the present inven-
tion is generally deslgnated 10 and is provlded ~or ~se
wlth a ~iber optlc cable or the like whlch has one or
more single optical ~lbers and a strength memberg as
de~cribed in greater detail hereina~ter The connector
assembly o~ the present invention is d~signed ~or
crlmping the strength member o~ the ~iber optic cable
SQ as to concentrate any stresses on the cable to the
strength member rather than the fragile optlcal ~ibers
durlng termlnation o~ the fibers or durlng ~ssembly and
~ield handll~g o~ the cable. More particularly, the
connector assembly 10 of the present invention includes
a connector body, generally designated 12~ ~or re-
ceiving one or more single optical fibers of the fiber
optic cable (de~cribed in gxeater detail hereina~ter~,
and a ~erxule member, generally designa~ed 14
Re~erring specifically to Figure 23 the fiber
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optic cable shown thereln -lncludes a fiber bundle 16
~ormed of a pluralit~ of ~ingle optical fibers. The
fiber bundle 16 is surrounded by an inner jacket 18,
and the inner ~acket 18 is surrounded by a ~trength
member 20 which extends beyond the end of the inner
~acket. The cable further includes an outer Jacket 22
whlch surrounds the strength member 20g but the cable is
cut so khat the strength member 20 as well as the inn~r
~acket 18 extend beyond the outer jacket 22g as shownO
The connector body 12 shown in ~igure 2 includes
a larger diameter portion 24 and a smaller dlameter rear
end portion 26 over which the strength member 20 of the
fiber optic cable ls positioned. The rear end portion
~6 o~ the connector body 12 is provided with a plur-
ality of annular crimp receiv~ng~ generally V-shaped
peripheral grooves 28. The rear end portion 26 o~ the
connector body 12 further is provided w~th a transverse
abutment surface 30 ~or engaging the end 32 of ~he
inner ~acket 18 of the cable providing an inter~ace
bekween the cable and the connector body when the cable
ls terminated thereto.
The ferrule member 14 of the connector assembly
10 shown in ~igure 2 has a first crimping portion which
i8 de~lned b~ a plurality o~ generally V-shaped crlmplng
ribs 34 wh~ch are alignable with the grooves 28 of the
connector body 12. The strength member 20 of the fiber
optic cable is crimped or clamped between the connector
body 12 and the ferrule member 14 in the area o~ the
grooves 28 and the ribs 34 o~ the body and ferrule,
respectively. The ~errule member 14 ~urther includes a
second crimping portion de~ined by a plurality of ribs
36 formed on the ~errule member rearwardl~ o~ the
crimplng rib~ 34 and sep~rated there~ram by a straight
~ntermediate portion 38 of the ferrule member. The
rlbs 36 of the ferrule member 14 are provided ~or crimp-
ing onto the outside of the strengt~l member 20 of the
fiber optic cable rearwardly of the inter~ace as at 30,
32 between the connector body 1~ and the inner ~acket
18 of the cable.
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The outslde diameter of the ferrule memher 14 is
the same as that of the larger diameter portion 24 of
the connector body 12 so as to avo~d any irregularit~es
and facllltate use of the connector assembly with
standard rear release insertlon/withdrawal field opera~
tion tools Furthermore, the outslde d~ameter of the
ferrule member 1~ adjacent the outer jacket 22 of the
flber optic cable preferably is the same as khe outside
diameter o~ the cable so as to avoid any lrregularikies
10 at the juncture of the outer ~acket 22 and the rerrule
member 140
Rei~erring to Figure 49 an enlarged, somewhat
schematic sectional view -ls presented which is taken
through a s~ngle crimp rece~ving groove 28 o~ the rear
15 end portion 26 of the connector body 1~. me groove 28
is shown allgned wlth a single rib 34 o~ the ferrule
member 14 with the strength member 20 of the fiber optic
cable removed to facilitate the illustratlonO In accor-
dance with the present invent~on, the lncluded angle
o~ each of the grooves 28 ~s smaller than that of the
corresponding rib 34 so as to .Lncrease the number of
crimp~ng diameters between the connector body 12 and the
ferrule member 1~. More spec~iaically, by so dimension-
ing the grooves ~8 and the ribs 34, the crimping areas
of contact between the connector body 12 and the ferrule
member 14 is along ~he edges Q~ the grooves 28~ as at
40 ln ~igure 4, so that this dlmensioning ls e~ective
to double the crimping diameters between the connector
body and the ~errule member~ Not only are the crimping
30 diameters ~ncreased, but sllppage of the s'crength member
20 is practically eliminated It further should be
pointed out that although the crlmp receivlng grooYes 28
of the connector body 12 and the crimping rlbs 34 of the
~errule member 14 are described at various times herein
35 as being generally V~shaped) such descriptlons in the
speclficatlon and claims hereof are intended to include
any such concave grooves and convex ribs which are so
dimensioned as to provide the multlple areas O.r crimping
cont~cts or dlameters along the edges o~ the grooves, as
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facllitated by the dimensioning described above. ~he
use of the term "V-shaped" in the ~pecificatlon and
claims herein is to facili~ate the illustratLon but ~n
no way to limit the description and claims.
Re~errlng to Figure 5~ a crimping dieg generally
deslgnated 42, is shown to include a split dle set com-
prislng an upper die 44 and a lower die 46. The connector
body 12 is provided wlth an annular, generally rectangular
rib 48 (Figures 2 and 3) which is posit-lonable within a
complementary generally rectangularly shaped groove 50
o~ the die set to facllitate pos~tionlng of the con-
nector body wlthin the die~ Each of the dies 44 and 46
is provided wlth an lnterior caVity, generally designated
52, which is provided with grooves and ribs so as to ~orm
the crimplng ribs 34 ~nd 36 of the ferrule member 1~
durlng a crimplng operation to termlnate the flber optic
cable to the connector assembly 10. The ferrule member~
prior to positioning into the crLmping die~ is tubular
ln the area o~ the crlmping ribs 34 and 369 and the ribs
are ~ormed or c~imped into the grooves 28 of the connec-
tor body during crlmplng operation of the dle 42.
Referring to Figure 3, the f-lber optlc cable
shown thereln -lncludes a single optical fiber 5~ surroun-
ded by an inner ~acket 56 which is surrounded by a
strength member 58 which, in turnJ is surrounded by an
outer Jacket 60. Like numerals are applied to the con-
nector bod~ l2 and the ferrule member 14 in Figure 3
which correspond to similar components thereo~ as
described in relation to Figures 2 and 4. However, the
connector body shown in F~gure 3 has a smaller diameter
bore portion 52 for receiving a single optical fiber 5
and a larger diameter bore portion 64 for receiving the
inner jacket 56 of the fiber optic c~ble.
The connector body 12 shown in Figure 3 does not
include the transverse abutment surface 30 as described
in relat-lon to ~he connector body shown in Figure 2~
As with the ~Lber opkic cable shown ~n Figure 2~ the
strength member 58 o~ the cable shown ln Figure 3 is
posltioned over the rear end 26 o~ the connector body 12
overlylng the crimping grooves 28 ~ormed thereln. ~he
rlbs 34 of the ferrule mem~er 14 are crlmped so as to be
nested ln the grooves 28 and are dimen~loned as described
above ln relation to Figure 4.
W~th the fiber optic cable shown in Figure 3,
the strength member ~ flares radially outwardly adjacent
~ the en~ of the outer ~ckek 60 o~ the cable and pro-
trudes rorwardly there~rom so as to be sandwiched-be-
tween the rear end portlon 26 o~ the connector body 12
and the ~errule mernber 14 and is crimped therebetween.
~he larger diameker portlon ~4 of khe connector body 12
and the adjacenk outslde diameter o~ the f'errule member
14 are generally the same so as to avold any lrregular-
ities as described above. The ~errule member 14 is
crimped to the outside of the outer jacket 60 o~ the
cable by the crimping ribs 36 rearwardl~ of the connector
body 12. Preferably9 the extreme rear or inner end of
the ~errule member 14 ls crlmped as at 68~ so as to bear
inwardly in gripping or bitlng engagement agalnst the
outside o~ the ~iber optic cable.
While ln the foregolng specl~lcation a detailed
descrlption o~ khe invention has been set forth ~or
purposes of illustratlon, variations o~ the detalls herein
given may be made by those skilled in the art without
departln~ ~rom the splrit and scope o~ the tnvention as
~et ~orth in the appended claln~s,
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