Optical waveguides – With disengagable mechanical connector – Structure surrounding optical fiber-to-fiber connection
Reexamination Certificate
2001-06-11
2004-02-24
Nasri, Javaid H. (Department: 2839)
Optical waveguides
With disengagable mechanical connector
Structure surrounding optical fiber-to-fiber connection
Reexamination Certificate
active
06695487
ABSTRACT:
BACKGROUND OF THE INVENTION
1. Field of the Invention
This invention relates to conversion adapters to be used for interconnecting optical connector ferrules having different diameters and methods for the production thereof.
2. Description of the Prior Art
In an optical connector which is used to facilitate the connection and the disconnection of two optical fibers or of an optical fiber and other optical element, like the SC type optical connector, for example, the predominantly used system comprises fitting one end of an optical fiber into an axial through-hole of a ferrule and inserting two ferrules thus prepared into an alignment sleeve through the opposite ends thereof to abut end faces of the ferrules against each other.
In order to directly align and connect the two ferrules to be connected by the above-mentioned system, it is necessary to align respective axes with very high accuracy because the diameter of a core thereof is small.
The use of the sleeve for aligning the ferrules each having an optical fiber inserted and fixed therein by abutting end faces thereof against each other includes the case where the optical connector plugs having the same ferrule diameter are mutually connected and the case where the optical connector plugs having different ferrule diameters are mutually connected. As a conversion adapter (sleeve) for connecting the optical connector plugs having different ferrule diameters, heretofore, those having the structures as shown in FIG.
1
through
FIG. 5
are known in the art.
The conversion adapter
1
shown in
FIG. 1
is a split sleeve comprising a large diameter part
2
having a large diameter through-hole “a”, into which a large diameter ferrule
10
having an optical fiber
12
inserted and fixed therein is fitted, and a small diameter part
3
formed by reducing a diameter in one end portion of the large diameter part and having a small diameter through-hole “b” into which a small diameter ferrule
11
having an optical fiber
12
inserted and fixed therein is fitted, the sleeve having a slit
4
formed in the longitudinal direction thereof so as to elastically hold the ferrules
10
and
11
having different diameters. The large diameter part and the small diameter part are integrally formed of metal or plastic.
The conversion adapter
1
shown in
FIG. 2
, on the other hand, is a precision sleeve having a large diameter through-hole “a” in a large diameter part
2
and a small diameter through-hole “b” in a small diameter part
3
formed in series along the axis thereof to form a step in the inside surface thereof. The large diameter part and the small diameter part are integrally formed of metal.
The conversion adapter
1
shown in
FIG. 3
is a double tube type precision sleeve comprising a large diameter sleeve
2
a
made of metal and a small diameter sleeve
3
a
of metal fitted and fixed in one end part of the large diameter sleeve
2
a.
The conversion adapter
1
shown in
FIG. 4
is a precision sleeve of the split sleeve type comprising a large diameter split sleeve
2
a
of metal having a slit
4
formed in the longitudinal direction thereof and a small diameter precision sleeve
3
a
of metal fitted and fixed in one end part of the large diameter split sleeve
2
a.
Further, Japanese Patent Application, KOKAI (Early Publication) No. (hereinafter referred to briefly as “JP-A-”) 9-90169 discloses a conversion adapter
1
comprising a large diameter part
2
into which a large diameter ferrule of an optical connector plug is fitted and a small diameter part
3
into which a small diameter ferrule is fitted, the large diameter part and the small diameter part being integrally formed of a synthetic resin such as, for example, a glass fiber-reinforced synthetic resin. The adapter has the structure such that a step is formed in the inside surface at the contact point between the large diameter part and the small diameter part and a groove
5
for air leakage is formed in the inside surface of the large diameter part in the axial direction thereof, as shown in FIG.
5
.
As mentioned above, metal such as phosphor bronze and plastics as mentioned in JP-A-9-90169 are heretofore used as a material for the conversion adapter to be used for interconnecting the optical connectors having different ferrule diameters.
In the case of plastics, however, since they are deficient in mechanical strength and wear resistance, the decrease in the accuracy of the axial alignment of ferrules to be connected and the deformation or the deterioration of characteristics of the adapter itself are unavoidable in the conversion adapter to which attachment and detachment of the ferrule are repeatedly performed. Moreover, plastics have the difficulty that their resistance to weather (durability against the change in temperature or humidity) is low and they lacks in the reliability of prolonged use.
On the other hand, in the case of metal such as phosphor bronze, since the machining such as cutting should be performed to obtain the complicated shape like the conversion adapter, besides the above drawbacks, it takes much time to manufacture the conversion adapter and the cost of machining is large. As a result, the obtained product is inevitably expensive.
SUMMARY OF THE INVENTION
It is, therefore, an object of the present invention to provide a highly reliable and inexpensive conversion adapter which excels in mechanical strength and wear resistance, causes only sparingly deformation and wear even by repeated attachment and detachment of ferrules, and can maintain the accuracy of the axial alignment of ferrules for a long period of time.
A further object of the present invention is to provide a method which is capable of producing such an conversion adapter with high productivity at a low cost.
To accomplish the object mentioned above, in accordance with one aspect of the present invention, there is provided a conversion adapter to be used for connecting opposed optical connector ferrules having different diameters, which adapter is characterized by being formed of an amorphous alloy possessing at least a glass transition region, preferably a glass transition region of a temperature width of not less than 30K.
In a particularly preferred embodiment, the conversion adapter is characterized by being formed of a substantially amorphous alloy having a composition represented by either one of the following general formulas (1) to (6):
M
1
a
M
2
b
Ln
c
M
3
d
M
4
e
M
5
f
(1)
wherein M
1
represents either or both of the two elements, Zr and Hf; M
2
represents at least one element selected from the group consisting of Ni, Cu, Fe, Co, Mn, Nb, Ti, V, Cr, Zn, Al, and Ga; Ln represents at least one element selected from the group consisting of Y, La, Ce, Nd, Sm, Gd, Tb, Dy, Ho, Yb, and Mm (misch metal: aggregate of rare earth elements); M
3
represents at least one element selected from the group consisting of Be, B, C, N, and O; M
4
represents at least one element selected from the group consisting of Ta, W, and Mo; M
5
represents at least one element selected from the group consisting of Au, Pt, Pd, and Ag; and a, b, c, d, e, and f represent such atomic percentages as respectively satisfy 25≦a≦85, 15≦b≦75, 0≦c≦30, 0≦d≦30, 0≦e≦15, and 0≦f≦15.
Al
100−g−h−i
Ln
g
M
6
h
M
3
i
(2)
wherein Ln represents at least one element selected from the group consisting of Y, La, Ce, Nd, Sm, Gd, Tb, Dy, Ho, Yb, and Mm; M
6
represents at least one element selected from the group consisting of Ti, V, Cr, Mn, Fe, Co, Ni, Cu, Zr, Nb, Mo, Hf, Ta, and W; M
3
represents at least one element selected from the group consisting of Be, B, C, N, and O; and g, h, and i represent such atomic percentages as respectively satisfy 30≦g≦90, 0<h≦55, and 0≦i≦10.
Mg
100−p
M
7
p
(3)
wherein M
7
represents at least one element selected from the group consisting of Cu, Ni, Sn, and Zn; and p represents an atomic percentage falling in the range of 5≦p≦60.
Mg
100−q−r
M
7
q
M
8
r
&ems
Kobayashi Masayuki
Nagahama Hidenobu
Sugita Etsuji
Takeda Hideki
Taniguchi Takeshi
Finnegan, Henderson, Farrabow, Garrett & Dunner, L.L.P
Nasri Javaid H.
YKK Corporation
LandOfFree
Conversion adapter for ferrules having different diameters... does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Conversion adapter for ferrules having different diameters..., we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Conversion adapter for ferrules having different diameters... will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-3304940