JP2827390B2 - Optical-electrical converter - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Application Field] The present invention relates to an optical device used in an optical transmission system comprising a light emitting / receiving element, a light receiving / emitting circuit and an electric output circuit.
Related to biographical converter.

[Conventional technology]

FIG. 10 is a perspective view showing a combined portion of an optical fiber and a light receiving / emitting element of a conventional optical-electrical converter. The light receiving / emitting end of the optical fiber 1 is subjected to a terminal treatment involving a caulking operation and a heating operation. Then, it is fixed to the plug connector 2. On the other hand, the light emitting and receiving element 3 is mounted on the opposite mating surface of the cap connector 4 combined with the plug connector 2, and the plug connector 2 is fitted into the cap connector 4 and assembled to combine the distal end face of the optical fiber 1 with the light emitting and receiving element 3. Are optically connected. In this case, the light emitting / receiving circuit and the electric output circuit are both mounted on the same printed circuit board 5 and are electrically connected to the light emitting / receiving element 3.

[Problems to be solved by the invention]

2. Description of the Related Art Conventionally, in an optical-electrical converter using an optical fiber, optical connection between the optical fiber and a light receiving / emitting element is performed using a commercially available connector. For this reason, it is expensive in terms of the configuration of the optical-electrical converter, and since the light receiving / emitting circuit and the electric output circuit are mixed, there is a possibility that the device is adversely affected by electromagnetic noise and malfunctions. In addition, the work of connecting the optical fiber and the plug connector requires a crimping work for terminal treatment of the optical fiber, a heating work using a hot plate, and the like, so that there is also a problem that the work is cumbersome and the number of man-hours is increased.

SUMMARY OF THE INVENTION In view of the above-mentioned problems, it is an object of the present invention to simplify the terminal processing of an optical fiber, easily connect an optical fiber to a light emitting and receiving element, and cause a malfunction without light interference and light leakage between the light receiving and emitting element. To provide a highly reliable optical-to-electrical converter.

[Means for solving the problem]

According to the present invention, an optical signal transmitted by an optical fiber is converted into an electric signal through a light receiving element, a light receiving circuit, and an electric output circuit, input to an external electric circuit, and the electric signal output from the external electric circuit is converted into an electric signal. Light that is converted into an optical signal via an output circuit, a light emitting circuit, and a light receiving element and transmitted to an optical fiber.
In an electric converter, an opaque hexahedral rectangular parallelepiped, an optical fiber insertion hole drilled from the front side thereof, and light emission formed by drilling from one side surface in orthogonal communication with the optical fiber insertion hole. An element storage chamber, a storage case having a light receiving element storage chamber formed by drilling from the other side surface, a first printed circuit board on which the light emitting circuit and an electric output circuit connected thereto are mounted, and A second printed circuit board on which a light receiving circuit is mounted, and the first printed circuit board and the first printed circuit board so as to close the opening of the light emitting element storage chamber storing the light receiving element and the light receiving element storage chamber storing the light receiving element. Sandwiched between two printed circuit boards.

(Operation)

With this structure, if the optical fiber is inserted into the optical fiber insertion hole of the light receiving and emitting element storage case in a free cut state without performing terminal treatment, the tip of the optical fiber contacts the light receiving and emitting element and the optical axis of the optical fiber and the light receiving and emitting light Optical connection is performed with the optical axes of the elements aligned. The light-emitting element storage chamber and the light-receiving element storage chamber perforated in the opaque light-receiving and light-emitting element storage case are closed by the printed circuit board, so that there is no light leakage from the light-receiving and light-emitting elements stored in the storage chamber. In addition, light interference between the light emitting and receiving elements is eliminated. The light emitting circuit is mounted on a printed circuit board together with the electric output circuit, and the light receiving circuit is mounted on another printed circuit board. Both printed circuit boards are provided separately with a light receiving and emitting element storage case therebetween, so that they are easily affected by noise. The light receiving circuit is not mixed with the electric output circuit and does not suffer from adverse effects due to noise.

〔Example〕

FIG. 1 is a configuration diagram showing an example of an optical transmission system using an optical-electrical converter according to an embodiment of the present invention, in which main components of the optical-electrical converter are light-emitting elements 11a, 11c, and light-receiving element 11b. ,
The light emitting circuits 12a and 12c, the light receiving circuit 12b, and the electric output circuit 13. In FIG. 1, an optical signal emitted from a light emitting element 11a of a light emitting circuit 12a is guided to a light detection operation device such as an optical limit switch 16 via an optical fiber 15a, where the light is transmitted or transmitted according to the operation of the light detection operation device. It is shaded. Accordingly, the optical signal is received by the light receiving element 11b of the light receiving circuit 12b of the optical-electrical converter via the optical fiber 15b, and the ON / OFF of the optical limit switch 16 is detected. The electric output circuit 13 turns on / off an output element such as a transistor (not shown) based on the above-mentioned light ON / OFF signal, and outputs an output signal to an external electric circuit 14. The light emitting element 11c of another light emitting circuit 12c performs light output display by an electric signal from an external electric circuit 14 when the light-to-electric converter is in an ON state, and the light signal is guided to a detection operation side by an optical fiber 15c. The light signal indicator 17 is turned on directly to display.

2 is a plan view of the optical-electrical converter of the present invention, FIG. 3 is a sectional view taken along the line AA of FIG. 2, FIG. 4 is a side view showing a combination of two printed boards, FIG. FIG. 6 is a front view of the light receiving / emitting element storage case, as viewed in the direction of the arrow P in FIG. 4, and FIG. 7 is a cross-sectional view as viewed in the direction of the arrow BB in FIG. Light emitting circuit of optical-electrical converter
12a and 12c are the first printed circuit board 1 together with the electric output circuit 13.
8a, and the second printed circuit board 18b has a light receiving circuit 12b
Only has been installed. These two printed circuit boards 18a, 18
“b” is fixed at regular intervals in parallel with the light receiving / emitting element storage case 19 interposed therebetween by a method such as screwing. The light-receiving / emitting element storage case 19 is made of an opaque black molded product, for example, and is provided with a plurality of optical fiber insertion holes 20 and a light-emitting element storage chamber 21a and a light-receiving element storage chamber 21b communicating therewith. The light-receiving element storage chamber 21b of the light-receiving element storage chamber 21a is separated such that the direction of drilling is perpendicular to the optical fiber insertion hole 20, for example, the light-emitting element storage chamber 21a is on the right side, and the light-receiving element storage chamber 21b is on the left side. After the light emitting elements 11a, 11c and the light receiving element 11b are stored in the light emitting element storing chamber 21a and the light receiving element storing chamber 21b, respectively, the openings of the light emitting element storing chamber 21a and the light receiving element storing chamber 21b are respectively connected to the first printed circuit board. 18a and the second
The printed circuit board 18b is closed. The optical fiber insertion hole 20 is a tapered hole having a polygonal cross section. The innermost square hole diameter is slightly smaller than the outer diameter of the optical fiber, and the square hole diameter near the entrance is slightly larger than the outer diameter of the optical fiber. , And the innermost entrance has a bell mouth shape. For this reason, it is extremely easy to insert the optical fibers 15a, 15b, 15c into the optical fiber insertion holes 20 of the light receiving / emitting element storage case 19 respectively, and the inserted optical fibers 15a, 15b, 15c and the light emitting element storage chamber 21a, Light-emitting elements 11a, 1 stored in element storage chamber 21b
1c and the optical axis of the light emitting element 11b are configured to coincide.

In addition, a plurality of optical fiber through holes 22 are provided on the wall surface of the cover 25 that is in contact with the front surface of the hexahedral rectangular parallelepiped of the light receiving and emitting element storage case 19, and the optical fiber through hole 22 is provided on the light receiving and emitting element storage case 19 side. It is coaxial with the optical fiber insertion hole 20. A holding member 23 for tightening or loosening the optical fibers 15a, 15b, 15c inserted in the optical fiber through hole 22 is also provided.
The press fitting 23 is operated by operating a lever 24. 3 shows a state in which the lever 24 is in a normal position and the holding member 23 is in a position for tightening the optical fibers 15a, 15b and 15c. FIG. 8 raises the lever 24, and the holding member 23 moves the optical fiber 15a. 9, 15b, and 15c are in a cross-sectional view showing a state in which they are loosened, and FIG. 9 is a front view as viewed in the direction of arrow Q in FIG. The light receiving / emitting element storage case 19 is connected to two printed circuit boards 18a,
4 and 5 are housed in the case 26, and each of the lower parts of the printed circuit boards 18a and 18b is provided with a plurality of thin walls provided inside the bottom of the case 26. It is positioned by being sandwiched between the projections 27, and is fixed by crushing the thin projections 27. When the cover 25 is fitted over the case 26 and fitted, the upper portions of the two printed circuit boards 18a and 18b abut against the inner surface of the cover 25 and are fixed. A connection terminal 28 for an external electric circuit is provided on an upper portion of the cover 25, and the connection terminal 28 for the electric circuit is connected to the printed circuit board 18a.
Is electrically connected to an electric output circuit 13 mounted together with the light emitting circuit 12b. A rail mounting fixture fixing portion 30 having a mounting bolt insertion hole 29 is integrally provided on one of the bottom outer surfaces of the case 26, and a rail mounting slider portion having a mounting bolt insertion hole 29 is provided on the other outside of the bottom of the case 26. 31 is slidably mounted. As a result, the optical-electrical converter can be directly mounted on a panel surface of a switchboard or the like by using two mounting bolt insertion holes 29, and the rail mounting members 30, 31 are used for mounting rails provided on the panel surface. By doing so, it can be attached to any position.

〔The invention's effect〕

According to the present invention, the light receiving circuit is provided in parallel with the electric output circuit by providing the printed circuit board on which the light emitting circuit and the electric output circuit are mounted and the printed circuit board on which only the light receiving circuit is mounted so that the light receiving and light emitting element storage case is sandwiched and provided side by side. The light-receiving circuit, which does not coexist and needs to increase the amplification as much as possible, is isolated from the electric output circuit which causes noise intrusion, so that it is possible to provide a highly reliable optical-electrical converter without being affected by noise. Since the openings of the light-emitting element storage chamber and the light-receiving element storage chamber provided in the light-receiving and light-emitting element storage case are respectively closed by a printed circuit board, light interference and light leakage between the light-emitting element and the light-receiving element stored in the storage chamber are prevented. There is no danger of malfunction. The optical fiber insertion holes communicating with the light receiving / emitting element storage chamber in the light receiving / emitting element storage case are perpendicular to each other, and the insertion holes are tapered to have a polygonal cross section, so that the optical fiber inserted and the optical axis of the light receiving / emitting element are inserted. It is possible to provide an optical-to-electrical converter in which the cores can be exactly fitted and light loss is small. Further, a hole structure of the optical fiber insertion hole of the light receiving / emitting element storage case described above is provided by providing a coaxial optical fiber through hole on a cover surface which abuts the optical fiber insertion hole and providing a holding member by lever operation in the through hole. In conjunction with this, the optical connection operation with the light emitting / receiving element can be performed only by inserting the free cut optical fiber and operating the lever without performing the terminal treatment of the optical fiber tip.

[Brief description of the drawings]

FIG. 1 is a block diagram showing an optical transmission system using an optical-electrical converter according to one embodiment of the present invention. FIG. 2 is a plan view of the optical-electrical converter according to one embodiment of the present invention. 3 is a sectional view taken along the line AA of FIG. 2, FIG. 4 is a side view showing a state where two printed circuit boards are combined, FIG. 5 is a view taken along the arrow P of FIG. 4, and FIG. FIG. 7 is a cross-sectional view taken along the line BB of FIG. 6, FIG. 8 is a cross-sectional view of a place where an optical fiber through-hole is provided in the cover, and FIG. FIG. 10 is a front view as viewed in the direction of the arrow Q in FIG. 10, and FIG. 10 is a perspective view showing a combination portion of an optical fiber and a light receiving / emitting element in a conventional optical-electrical converter. 11a, 11c: light emitting element, 11b: light receiving element, 12a, 12c: light emitting circuit,
12b: light emitting circuit, 13: electric output circuit, 15a, 15b, 15c: optical fiber, 18a, 18b: printed circuit board, 19: light receiving and emitting element, 20: optical fiber insertion hole, 21a: light emitting element storage chamber, 21b: light receiving Element storage room.

Claims (1)

(57) [Claims] An optical signal transmitted through an optical fiber is converted into an electric signal through a light receiving element, a light receiving circuit, and an electric output circuit, input to an external electric circuit, and the electric signal output from the external electric circuit is converted. 2. Description of the Related Art An optical-electrical converter for converting an optical signal into an optical signal via an electric output circuit, a light emitting circuit, and a light emitting element and transmitting the converted signal to an optical fiber, comprising an opaque hexahedral rectangular parallelepiped, and an optical fiber insertion hole formed from the front side thereof. A storage case having a light-emitting element storage chamber formed by drilling from one side and orthogonally communicating with the optical fiber insertion hole, and a light-receiving element storage chamber formed by drilling from the other side. A first printed circuit board on which the light emitting circuit and an electric output circuit connected to the light emitting circuit are mounted, and a second printed circuit board on which the light receiving circuit is mounted; Electrical converter - room light, characterized in that the clamping of the storage case so as to close the opening of the light-receiving element housing chamber housing the light receiving element in the first printed circuit board and the second printed circuit board.