JPS6330601B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an optical fiber penetrating terminal plate, and relates to an optical fiber penetrating terminal plate that airtightly holds the penetrating portion of the optical fiber when the optical fiber end fiber is used in airtight equipment, for example. It is.

In recent years, the range of applications of optical fibers has become extremely wide, and in addition to communication equipment, they have also come to be used in heavy electrical equipment. For example, they have come to be used in high-voltage switchgear, transformers, generators, etc. Such equipment includes insulating media, arc-extinguishing media, sulfur hexafluoride (SF ₆ ) gas, compressed air, hydrogen,
Some use oil. In order to use optical fibers in these devices, airtight and oiltight through terminal plates are absolutely required.

Optical fibers come in a variety of configurations,
For example, a large number of filaments (consisting of a core wire and surrounding cladding layer) with a diameter of several microns are bundled together and a protective sheath is provided to protect the bundle, or a single filament with a diameter of 0.2 to 0.3 mm is used. Some have protective coatings. An example of this protective coating is a first polyester or nylon coating, a fibrous material layer, and a second polyethylene or polyvinyl chloride coating.

In order to apply such an optical fiber to the above-mentioned air-tight and oil-tight penetration terminal, conventionally the protective coating of the central part of the optical fiber passing through the terminal block was removed, and the terminal block was directly molded with epoxy casting material. It was configured as follows.

However, in the conventional structure of the optical penetration hermetic terminal board, after the terminal board is cast, the terminal board cast end face of the optical fiber penetration part is protected due to external stress applied when taking it out of the mold (released from the mold). The disadvantage is that the coating may peel off, break, or crack, or in the worst case, the wire may break, resulting in loss of light or inability to transmit light. On the other hand, when applied to equipment,
It is necessary to attach connectors to both ends of the optical fiber, which has the disadvantage of being extremely troublesome and expensive.

This invention was made in order to eliminate the drawbacks of the conventional ones as described above. An embodiment of the present invention will be described below with reference to the drawings.

FIG. 1 is a partial side sectional view showing an embodiment of an optical fiber penetrating terminal plate according to the present invention, and FIG. 2 is a detailed side sectional view of the portion shown in FIG. 1. In FIGS. 1 and 2, an optical fiber 1 is inserted through an airtight device and is coated with a primary protective coating such as nylon. The optical penetration connector 2 is for inserting the optical fiber 1 through the optical fiber 1 in an airtight manner. As shown in FIG.
a cylindrical external metal protection tube 201 inserted through the
Thread groove 201a on the inner peripheral surface of the external metal protection tube 201
An annular lid part 202 has a threaded groove 202a on the outer circumferential surface to be screwed into the external metal protection tube 201, and has a through hole 202b for passing the optical fiber 1 through, which is provided so as to cover the openings at both ends of the external metal protection tube 201; An end protection tube 20 made of quartz, ceramic, etc. is inserted through the peeled part 101 from which the protective coating on both ends has been peeled off.
3, and a metal tube 204 that is inserted through a part of the end protection tube 203 and the end of the optical fiber 1 from which the protective coating is not peeled off to guide and protect the tip of the optical fiber 1.
The optical fiber 1 protected by the end protection tube 203 and the metal tube 204 is housed, and the tip of the peeled part 101 of the optical fiber 1 is placed so that its tip surface 101a is flush with the bottom outer surface 205a of the cylindrical container. The peeling part 101 is inserted into the through hole 205b provided at the bottom of the cylindrical container, and the opening of the cylindrical container that contacts the end face of the external metal protection tube 201 and the outer surface of the lid part 202 protrudes in the outer radial direction. A cylindrical container-shaped plug 205 having a flange portion 205c provided with a flange portion 205c.
A flange portion 206a that accommodates the plug 205 and protrudes in the outer radial direction at one end and abuts the flange portion 205c, and a threaded groove 2 provided on the outer peripheral surface of the other end.
06b, a threaded groove 207a provided on the inner circumferential surface of one end and screwed into the threaded groove 201b provided on the outer circumferential surface of the end of the external metal protection tube 201, and a threaded groove 207a provided at the other end in the inner radial direction. A collar portion 20 that is provided in a protruding manner and comes into contact with the collar portion 206a.
7b and a set screw 207. The first adhesive 3 is made of, for example, epoxy resin with a strong adhesive strength, and is used to firmly fix the end of the optical fiber 1 to the lid 202 and the plug 205. filled in between. The second adhesive 4 has airtightness and is highly elastic, such as silicone.
It is made of RTV and holds the optical fiber 1 airtightly and elastically at both ends inside the external metal protection tube 201. In FIG. 1, the terminal plate 5 is integrally molded into a flange shape using an epoxy casting material, for example, except for at least both ends of a large number of optical penetration connectors 2, and has a mounting through hole 501 for mounting to a device with bolts or the like. An annular O-ring groove 502 into which an O-ring is inserted to maintain confidentiality with the device is provided. In FIG. 2, the device side plug 205' is inserted into the adapter 206 and joined to the outer surface 205a of the plug 205,
The end surface of optical fiber 1' on the equipment side and optical fiber 1
and the distal end surface 101a of the two are joined. The joining ring 6 is screwed into the thread groove 206'b of the device-side adapter 206' and the thread groove 206b of the adapter 206 to connect the device-side adapter 206' to the adapter 206. Note that the inner central portion 201b of the external metal protection tube 201 is not filled with the second adhesive 4 and is hollow, so that the optical fiber 1 can freely expand and contract.

This invention is constructed as described above, and the terminal plate 5 is cast into a flange shape using a casting material such as epoxy resin, so that a plurality of optical penetration connectors 2 are integrally cast at the same time. The airtightness and oiltightness of the parts can be ensured. In addition, the connection to optical fiber 1 on the device side and external side is plug 2.
This can be easily done by simply inserting a plug 205' similar to 05 into the adapter 206. Furthermore, the inner central portion 201b of the outer metal protection tube 201
Since it is hollow, displacement of the optical fiber 1 due to expansion or contraction of the optical fiber 1 due to thermal stress or the like can be prevented, and reliability is increased.

As described above, according to the present invention, the airtightness of equipment,
It has various effects such as ensuring oil tightness, facilitating the connection of optical fibers, and increasing reliability.

[Brief explanation of the drawing]

FIG. 1 is a partial side sectional view showing an embodiment of an optical fiber penetrating terminal plate according to the present invention, and FIG. 2 is a detailed side sectional view of the portion shown in FIG. 1. In the figure, 1 is an optical fiber, 101 is a peeling part, 101a is a tip surface, 2 is an optical penetration connector, 2
01 is an external metal protection tube, 202 is a lid, 203 is an end protection tube, 204 is a metal tube, 205 is a plug,
206 is an adapter, 207 is a set screw, 3 and 4 are first and second adhesives, and 5 is a terminal board. Note that the same parts in each figure are given the same reference numerals.

Claims (1)

[Claims] 1. An optical fiber hermetically held in a cylindrical optical penetration connector so that both ends thereof are exposed to the outside;
and an optical fiber feed-through terminal plate including a terminal plate integrally cast with the optical feed-through connector except for at least both ends of the optical feed-through connector, wherein the optical fiber is hermetically sealed to the optical feed-through connector at both ends thereof. The optical fiber penetration terminal board is characterized in that the optical penetration connector has an airtight space inside so that the optical fiber can be freely expanded and contracted in the central part excluding both ends. 2 The protective coating is removed from both ends of the optical fiber,
Both ends of the optical fiber from which the protective coating has been peeled off are inserted into the bottom through-hole of a container-shaped plug, and the opening of the container-shaped plug is an external metal protection tube that constitutes the outer frame of the cylindrical optical penetration connector. 2. The optical fiber penetrating terminal board according to claim 1, wherein the optical fiber penetrating terminal board is attached so as to close both end openings of the optical fiber, and the end surfaces of both ends of the optical fiber are flush with the bottom outer surface of the plug. 3. A patent in which both ends of the optical fiber from which the protective coating has been peeled are covered with an end protection tube, and a part of the end protection tube and both ends of the optical fiber with the protective coating are covered with metal tubes. An optical fiber penetrating terminal plate according to claim 2. 4. The optical fiber penetrating terminal board according to claim 3, wherein a first adhesive having high adhesive strength is filled between the end protection tube and the metal tube and the plug. 5. The optical fiber penetration terminal according to any one of claims 2 to 4, wherein both ends of the external metal protection tube are filled with a second adhesive having excellent adhesion and elasticity. Board.