JPS63267902A - Submersible optical rotary connector - Google Patents

Abstract

PURPOSE:To improve the precision of optical rotary parts to attain optical connection of stable small loss by providing optical rotary parts and a closed vessel coating these parts to obtain a double structure. CONSTITUTION:Optical rotary parts 10 and a closed vessel 20 which covers optical rotary parts 10 and can be rotated synchronously with them are provided. A hydraulic pressure-resisting optical fiber lead 30 used to fix the terminal of an optical fiber 31 into optical rotary parts 10 is incorporated in the closed vessel 20. An optical oil 0 is filled in internal spaces of optical rotary parts 10 and the closed vessel 20. Optical rotary parts 10 are so constituted that a fiber fixing ring 11 and a fiber rotating ring 14 can be rotated by rotary bearing parts (bearings) 15a and 15b. With respect to the fiber rotating ring 14, a cylinder ring part 14a and an annular part 14b are coupled to each other by screws. Thus, optical coupling is performed with a high precision and the optical coupling loss is stabilized.

Description

[Detailed Description of the Invention] [Field of Industrial Application] The present invention relates to an underwater optical rotary connector, and more particularly, to an underwater optical rotary connector that has a rotatable optical coupling part to eliminate twisting of an optical fiber cable underwater. This relates to optical rotary connectors.

[Summary of the invention]

The present invention performs high-precision optical coupling by accommodating an optical fiber terminal in a double-structured rotatable connection container consisting of an optical rotary component and a closed container and absorbing external shocks. Eliminates air bubbles in the optical oil filled in the closed container to stabilize optical coupling loss, improves watertightness and prevents water from entering inside and oil from flowing out, creating an underwater optical rotary connector with stable functions. This is what I did.

[Conventional technology]

In recent years, fiber optic cables, which can transmit larger amounts of data than coaxial cables, have come into use as signal transmission lines for video monitors for submarine exploration and robots for submarine work.

This optical fiber cable is used by being unwound from a cable drum, which causes twisting and kinging in the cable, which deteriorates mechanical and transmission characteristics. Underwater optical rotary connectors that can be connected are used, and some have oil sealed inside them to match the refractive index of light at the optical fiber coupling part and to lubricate the bearing parts.

(For example, Utility Model Application Publication No. 61-143108) [Problem to be solved by the invention] However, such conventional underwater optical rotary connectors have a structure in which the tension member of the optical fiber cable is integrated, and the rotation The accuracy of the axial center depends on large bearings, and as a result of the large axial misalignment, there is a problem in that the optical coupling loss due to the extremely thin optical fiber becomes large.

In addition, air bubbles tend to remain in the oil for optical transmission sealed in underwater optical rotary connectors, and if oil containing air bubbles gets into the space between the optical fiber and the lens, the glass of the optical fiber or lens etc. Since there is a large difference in the refractive index of light between bubbles and air, there is a risk of increased optical coupling loss and instability due to reflection and refraction of light.

Furthermore, since the optical fiber introduction part does not have a completely watertight structure, water pressure is applied to the optical fiber core wire through the pendant, causing an increase in light loss due to reflection and refraction of light by the micropend. Due to imperfections, there is also a risk of oil leaking from the connector side to the cable side.
This invention has problems such as not being able to be used under high water pressure such as deep sea.The present invention solves the problems of optical coupling loss due to axis misalignment and optical coupling loss due to air bubbles in oil, which conventional underwater optical rotary connectors have. , aims to solve problems such as micropend and optical coupling loss due to imperfections in the watertight structure, as well as oil leakage.

[Means for solving problems]

In order to achieve the above object, the present invention provides the following underwater optical rotary connector. That is, the present invention provides an optical rotary component that accommodates the ends of optical fibers from both sides and optically connects them to each other in a rotatable manner, and an optical rotary component that accommodates this optical rotary component and is filled with optical oil having a refractive index equivalent to that of the optical fiber glass.・Constructed of a closed container that is sealed and rotatable with respect to each other in synchronization with the rotation of the optical rotary component, and a water-resistant optical fiber lead that attaches the optical fiber terminated to the optical rotary component; The rotary component is composed of a fiber fixing ring and a fiber rotating ring, and the fiber fixing ring and the fiber rotating ring have a through hole through which the optical oil flows into the internal gap, and the fiber fixing ring has both end surfaces thereof The closed container has a light guide that faces the end surface of the optical fiber through optical oil and transmits an optical signal, and the closed container includes a closed container fixed ring and a closed container rotating ring. It has a degassing and sealing mechanism for degassing and sealing the optical fiber, an internal pressure adjustment mechanism for adjusting the internal pressure to changes in external pressure, and an oil injection sealing mechanism for injecting and sealing optical oil. A flexible seal is provided between the lead and the water pressure resistant optical fiber lead. This is an optical fiber connector for

[Effect]

In the above configuration, the optical rotary component is configured such that the fiber fixing ring and the fiber rotation ring are rotatable, so by connecting both ends of the optical rotary component to the device and the cable retaining section via the bracket, the cable or device can be rotated. However, the twist will be resolved.

Further, with this rotation, the closed container fixing ring rotates with the fiber fixing ring of the optical rotary component, and the closed container rotating ring rotates with the fiber rotating ring.

The optical oil filled and sealed in the closed container serves as a medium for maintaining internal pressure and transmitting optical signals.

The optical guide of the optical rotary component transmits the optical signal from one optical fiber end face to the other optical fiber end face together with the optical oil flowing through the through hole of the outer cylinder.

The degassing and sealing mechanism of the closed container has the function of removing air bubbles in the optical oil, increasing the transparency of the optical oil, and stabilizing the oil by deaerating the inside and increasing the degree of vacuum.

Furthermore, when the external water pressure is high, the internal pressure adjustment mechanism of the closed container extends inward to increase the oil pressure of the optical oil, thereby automatically maintaining a balance between the external water pressure and the internal oil pressure.

The oil injection sealing mechanism of the closed container immediately seals the optical oil after injecting the optical oil from the optical oil supply source, maintains the degree of vacuum by degassing the interior, and prevents bubbles from forming in the optical oil.

Furthermore, the flexible seal installed between the closed vessel rotating ring and the water pressure resistant optical fiber lead flexibly connects the closed vessel rotating ring and the water pressure resistant optical fiber lead, and allows the closed vessel rotating ring to be unforced. Even if an external force is applied, it flexibly absorbs that external force.

A water pressure resistant optical fiber lead uses a highly precisely aligned ferrule to accurately fix the terminated optical fiber to its axis, thereby preventing the axis from shifting due to rotation.

〔Example〕

DESCRIPTION OF THE PREFERRED EMBODIMENTS Regarding embodiments of the present invention, how the configuration of the present invention is actually embodied will be described below with reference to the drawings, along with its operation.

FIG. 1 is a perspective view of one embodiment of the present invention, and FIG. 2 is a sectional view thereof. In these figures, reference numeral 10 denotes an optical rotary component, which is comprised of components described below with reference numerals 11 to 17.

There is a closed container 20 that covers this optical rotary component 10 and can rotate with respect to each other in synchronization, and this closed container 20 is designated by reference numerals 21 to 21.
It is composed of parts indicated by 29.

Further, a water-resistant optical fiber lead 30 for fixing the end of an optical fiber 31 within the optical rotary component 1O is built in the closed container 20, and this optical fiber lead 30
is formed by parts described below by reference numerals 32 to 34.

The internal voids of the optical rotary component 10 and the closed container 20 are filled with optical oil 0 having a refractive index of about 1.45.

This optical rotary component 10 includes a fiber fixed ring 11 and a fiber rotating ring 14, and a rotating bearing component (bearing) 15.
a and 15b so that they can rotate with respect to each other.

The fiber rotating ring 14 has a cylindrical ring portion 14a and an annular portion 14b.
and are connected to each other by screws (not shown).

A light guide 12 for transmitting optical signals is installed inside the fiber fixing ring 11, and the light guide 12 is formed by inserting an optical fiber glass into the center of a ceramic or metal ferrule bonded within a metal sleeve. has been done.

Further, by attaching a nut 16 to the fiber fixing ring 11, the one-rotation bearing allows the parts 15a and 15b to be stably attached to the cylindrical portion 11a of the fiber fixing ring 11, and the fiber rotating ring 14 is attached to the fiber fixing ring 11. Connect rotatably.

The fiber fixed ring 11 and the fiber rotating ring 14 each have a plurality of through holes 17, which allow the optical oil 0 to communicate with them, and fill the gaps near the end face of the optical fiber 31 and the rotating bearing near the parts 15a and 15b. There is.

The liquid pressure of the optical oil O is uniformly transmitted to the internal cavity through the plurality of communication holes 17, and the pressure of the optical oil O is always balanced inside and outside the optical rotary part, so air bubbles are generated in the oil. Therefore, the optical coupling loss is also kept constant.

Further, the communication via hole 14c of the fiber rotating ring 14 of the optical rotary component 10 has a hole diameter that is 1.2 to 2 times the diameter of the pin 29 of the closed container rotating ring 22, and this play gap allows the light to be Since the misalignment of the rotation axes between the rotary component 10 and the closed container 20 is absorbed, even if an external force is applied to the closed container KO, the optical rotary component 10 is not deformed, and therefore the optical axis is kept constant and rotation The structure is such that stable optical coupling loss can be guaranteed even when

Note that the fiber fixing ring 11 is fixed to the closed container fixing ring 21 with a fastening screw 13 via a washer 13a.

The closed container 20 consists of a closed container fixed ring 21 and a closed container rotating ring 22, both of which are rotatably coupled to each other by interposing a thrust type rotation bearing part 23a and a radial type rotation bearing part 23b. There is.

Further, by screwing the end plate 24 to the closed container fixing ring 21 side, the radial type rotary bearing encloses the component 23b and the thrust type rotary bearing encapsulates the component 23a, and the end plate 24 encloses the component 23b for fixing the closed container. Keep watertight between ring 210
The ring or backing 25a is also attached to the closed container rotating ring 2.
2, there is a rotating shaft sealing part 25b such as an O-ring,
25c is interposed to prevent water from entering from the outside and optical oil O from flowing out from the inside, thereby stabilizing various functions.

Further, a flexible diaphragm 26 (internal pressure adjustment mechanism) is hermetically attached to the closed container rotating ring 22 using a plate 27 .

This is to keep the pressure of the optical oil 0 inside the closed container 20 in balance with the pressure of liquid such as water or seawater outside the same, and when the outside liquid pressure is high, this diaphragm 26 The diaphragm 26 extends inward to compress the optical oil 0, and conversely, when the external liquid pressure is low, the diaphragm 26
is contracted and the internal optical oil 0 expands, and the internal and external liquid pressures are balanced.

As a result, for example, the thrust type rotary bearing has parts 23a,
In the radial rotary bearing, the internal and external pressures of all components such as the component 23b and the end plate 24 are balanced, no excessive force is applied, so no distortion occurs, and the rotational function and watertight function are maintained for a long period of time.

Further, the closed container rotating ring 22 has an optical oil injection hole 28a with a sealing plug (oil injection sealing mechanism), and the closed container fixed ring 21 has a vacuum degassing hole 28b with a sealing plug (degassing sealing mechanism). There is.

When injecting the optical oil O into the inside of the closed container 20 using these methods, first assemble the optical rotary component 10, the closed container 20, and the water pressure optical fiber lead 30, and then After connecting the oil injection hole 28a to the oil supply source and sealing it, the closed container fixing ring 21
The vacuum degassing hole 28b with a sealing plug is degassed to a sufficient degree of vacuum, and then the optical oil injection hole 28b with a sealing plug is degassed.
a, and after the optical oil 0 is injected and filled, both the injection hole 28a and the deaeration hole 28b are sealed.

As a result, the closed container 20 is filled with the optical oil O with excellent optical properties from which air bubbles have been removed, keeping optical coupling loss small and stable, and transmitting external water pressure uniformly to the entire optical oil. can.

Next, 30 is a water pressure resistant optical fiber lead, 31 is the central optical fiber, and 32 is the optical fiber 31.
A coating layer that protects the optical fiber from the outside.Generally, a cored optical fiber is composed of such an optical fiber and a coating layer.

33 is a water pressure resistant pipe that protects the optical fiber from water pressure;
4 is a ferrule.

This water pressure pipe protects the optical fiber from external pressure and suppresses optical loss due to microbending.

The ferrule 34 is a component that is aligned with the fiber fixing ring 11, the optical fiber coating layer 32, and the water pressure pipe 33 with a fitting tolerance of 0.001 mm or less and with high precision. The fitting surface of the optical fiber coating layer 32 and the water pressure pipe 33 is adhesively sealed and fixed.

The sealing section 35 includes a water pressure pipe 33 and a ferrule 34.
and are sealed.

Further, 36 is a cap nut, which fits and fixes the ferrule 34 and the circular ring 14b of the fiber fixing ring 11 or the fiber rotating ring 14.

With this structure, the only portions where pressure is applied to the optical fibers are the end faces of the tips of both optical fibers 31,
Therefore, it is possible to prevent an increase in optical loss due to microbending, and also to prevent the optical oil injected into the closed container from flowing out.

The closed container 20 and the water pressure pipe 33 are sealed by explosive contact or adhesion at a sealing portion 37 to prevent water from entering from the outside or optical oil from flowing from the inside.

The rotating ring 22 of the closed container and the water pressure pipe 33 are flexibly connected by tightening the vicinity of both ends of a bellows 38 (flexible seal) formed of soft rubber or the like using fastening fittings 39a and 39b.

Therefore, due to external force, the double-structured optical rotary component lO
Even if the axis of rotation of the closed container 20 is misaligned, no excessive force is applied to the water pressure pipe 33, so the optical coupling can remain stable.

In actual use, the fixed ring 21 and rotating ring 22 of the closed container are attached to the equipment and cable retaining part via appropriate brackets, and the cable and equipment side fiber are fused to the optical fiber lead via field through. The connection can be made according to the law.

Further, if the optical cable has a structure using a pressure-resistant pipe-coated fiber, the ferrule 34 may be attached to the cable and the cable may be directly connected to an optical rotary connector.

As described above with respect to the embodiments, the present invention prevents misalignment of the optical axis through a double structure, improves and stabilizes the optical properties of optical oil through deaeration, and stably maintains various functions through a watertight structure. It constitutes an underwater optical rotary connector.

〔Effect of the invention〕

As described above, according to the present invention, since the optical rotary component and the closed container covering the optical rotary component are provided to form a double structure, the optical rotary component can be highly accurate and a stable low-loss optical connection can be achieved.

Further, the optical rotary component is composed of a fiber fixed ring and a fiber rotating ring that are rotatable with each other, and a closed container covering the fiber fixed ring and a closed container that are rotatable with each other through a play gap with the optical rotary component are also provided. Since it is composed of a container rotating ring,
Even when external stress is applied to the closed container, it is possible to eliminate the occurrence of misalignment of the central axes of the optical fibers whose ends are fixed in the fiber fixing ring and the fiber rotating ring, respectively.

Furthermore, the closed container is filled and sealed with optical oil that has a refractive index equivalent to that of optical fiber glass, minimizing optical coupling loss such as catadioptric refraction due to differences in the refractive index of the transmission medium. be able to.

In addition, since the closed container has an internal pressure adjustment mechanism, the external water pressure and internal hydraulic pressure are automatically balanced, and undue force is not applied to the closed container or internal equipment, preventing deformation and distortion or wear of rotating parts. It also prevents water from entering and optical oil from flowing out.

At the same time, since the closed container is equipped with a degassing sealing mechanism and an oil injection mechanism, the generation of air bubbles in the optical oil can be prevented by degassing before injecting the optical oil and then adding the optical oil. Can be done.

In addition, the fiber fixed ring and rotating ring have holes penetrating the inside and outside, so the injected optical oil becomes uniform inside and outside the optical rotary part, eliminating the generation of bubbles and ensuring uniform transmission characteristics. It has the advantage of being able to maintain

[Brief explanation of drawings]

FIG. 1 is a partially cutaway perspective view of an embodiment of the present invention, and FIG. 2 is a sectional view of FIG. 1. 10... Optical rotary part, 11... Fiber fixed ring, l2... Light guide, 14... Fiber rotating ring, 17... Through hole, 20... Closed container, 21... Closed container fixed ring, 22... Closed container rotating ring, 26... Diaphragm (internal pressure adjustment mechanism) , 28
...Optical oil injection hole with sealing plug (oil injection sealing mechanism), 28b... Vacuum degassing hole with sealing plug (degassing sealing mechanism), 30... Resistance Hydraulic optical fiber lead, 34...
...Ferrule, 38...Herose (flexible seal). Figure 1

Claims (3)

[Claims] (1) An optical rotary component consisting of a fiber fixing ring and a fiber rotating ring that fix the ends of both optical fibers via ferrules and are mutually rotatably supported, and this optical rotary component is housed; It consists of a closed container consisting of a mutually rotatable closed container fixed ring and a closed container rotation ring filled with optical oil having a refractive index equivalent to that of the optical fiber, and the fiber fixing ring is fixed to the closed container fixed ring. . An underwater optical rotary connector, characterized in that the fiber rotating ring is connected to the closed container rotating ring through a play gap. (2) The underwater optical rotary connector according to claim (1), wherein the fiber fixing ring and the fiber rotating ring are provided with a plurality of small holes passing through the center thereof. (3) The underwater optical rotary connector according to claim (1), wherein the closed container is provided with a degassing sealing mechanism, an oil injection sealing mechanism, and an internal pressure adjustment mechanism.