Fiber optic hull penetrator insert

A fiber optic hull penetrator comprises a penetrator insert and a penetra plug that each have fiber alignment inserts mounted, molded or adhered to them. The penetrator insert and penetrator plug are designed to provide strain relief to the cable, spring loading to the fiber alignment inserts, and a waterproof pressure boundary seal when subjected to the submarine ocean and combatant environment. Each fiber alignment insert is a solid slug of material to which anchor pin holes, strength member holes, locating key holes have been added to which suitable components are affixed or inserted.

BACKGROUND OF THE INVENTION 
1. Field of the Invention 
The present invention relates to fiber optic hull penetration or bulkhead 
penetration. The connectors used in the penetration are to be suitable to 
interconnect multiple single or bundle fiber optic leads in an underwater 
pressure differential environment. 
2. Description of the Prior Art 
The development of fiber optic connectors to present has been devoted 
primarily to land based telecommunication and land based military 
applications in a ferrule-to-ferrule configuration. As a result, there are 
no known planar, waterproof, pressure differential multichannel 
penetrators. 
SUMMARY OF THE INVENTION 
The purpose of the fiber optic hull penetrator is the efficient 
transmission of modulated light from multiconductor, interchangeable 
outboard submarine cable across a pressure differential, waterproof, 
demateable interface to inboard submarine cable. The efficiency of the 
light transmission is accomplished by the precision of the fiber alignment 
inserts in the two halves of the connector. The design of the hull 
penetrator, the materials utilized; and the method of affixing the 
assembly to the hull are required to maintain the waterproof integrity of 
the submarine hull under operational and combatant conditions. 
The invention provides efficient light transmission by the precise 
positioning and polishing of the individual or bundle fiber in the fiber 
alignment holes of the fiber alignment inserts. The fiber alignment 
inserts are subsequently mounted, molded, or adhered to the hull 
penetrator body insert and plug. 
The principal advantage of invention is the size reduction of approximately 
one-half when compared to currently available electrical penetrators, thus 
reducing the number and size of hull penetrations. The fiber density can 
easily be varied by changing the configuration of the fiber alignment 
inserts. The fiber alignment insert can be changed to accept single fiber 
conductors or bundle fiber conductors of various sizes. The hull insert 
and penetrator body are totally reusable. The process by which the bonding 
agent is applied allows for an automatic self-centering of each fiber in 
its respective hole.

DESCRIPTION OF THE PREFERRED EMBODIMENT 
Referring now to FIG. 1 there is shown a hull penetrator connector assembly 
10 and a plug connector assembly 12. The hull insert 14 is welded to the 
hull 16 both inboard 18 and outboard 20. The welds 22 and 24 must be 
watertight and withstand a pressure differential. 
The hull insert 14 encloses a "K" monel connector body 26 that is held in 
place by a "K" monel washer 28 and a "K" monel nut 30. Watertight 
integrity is maintained by O-rings 32 and 34. 
The plug connector half 12 is affixed to the hull connector half 10 by 
means of threaded brass nut 36. The hull connector body 26 houses a molded 
assembly 38 that has an elastomeric shock spring 40 interfacing the molded 
assembly 38 and the connector body 26. The spring 40 is held in place by 
washer 41. Keying pin 43 properly aligns molded assembly 38. Watertight 
integrity is maintained between the molded assembly 38 and the connector 
body 26 by means of an O-ring 42. The molded assembly 38 contains a 
titanium fiber alignment insert 44. The hull connector half 10 is aligned 
with the plug connector half 12. The plug half contains a titanium fiber 
insert 46 which is encased within plug shell 48 with an epoxy molding 
compound 50 and the shell 48 is encased in an elastomeric molding compound 
52. Penetrator fiber alignment insert 44 and plug fiber alignment insert 
46 are identical. Fiber optic leads 54 and 56 are shown being received by 
alignment insert 46 and 44 respectively. Watertight integrity between hull 
connector half 10 and plug connector half 12 is maintained by O-ring 57. 
FIGS. 2 and 3 show enlarged views of a fiber alignment insert 46. Since 
plug fiber alignment insert 46 is identical to penetrator insert 44 
separate views of insert 44 are not necessary. 
Referring now to FIGS. 2 and 3 there is shown the fiber alignment insert 46 
made of titanium for the purpose of corrosion resistance and to minimize 
the mass. The insert 46 has a large locating keying pin aperture 58 that 
has a locating pin 60 inserted. There is also a small locating keying pin 
aperture 62 having a locating pin 64. Fiber optic conductor holes 66 are 
counterbored for holding the jacketed fiber. To connect the fiber leads to 
conductor holes 66, an epoxy bonding agent is drawn through conductor 
holes 66 by vacuum means. A plurality of strength member holes 68 are also 
provided. Permanent anchor pins 70 are inserted in the after end of insert 
46. Pin 70 provides anchor points and adds torsional strength when the 
insert 46 is potted. In operation, signals on fiber optic leads 54 are 
transmitted through inserts 46 and 44 to leads 56. It is to be noted that 
the fiber guide holes 66 that transmit signals have no mechanical 
interlocking as in a normal pin and socket arrangement. The spring loading 
design accomplished by the elastomeric spring provide continual interface 
contact when subjected to shock waves encountered in a hostile 
environment. 
The design permits repolishing without disassembly of components. It would 
be advisable to do this during major overhauls. The fiber lead faces have 
a separation of substantially one mil. This can be maintained by either a 
transparent elastomer film or an index matching gel. 
It will be understood that various changes in the details, materials, steps 
and arrangement of parts, which have been herein described and illustrated 
in order to explain the nature of the invention may be made by those 
skilled in the art within the principle and scope of the invention as 
expressed in the appended claims.