JPH0441308Y2 - - Google Patents

Description

[Detailed Description of the Invention] (Industrial Application Field) The present invention relates to a fire detection device, and more particularly to a photoelectric conversion amplifier for a multi-view fire detection device using optical fibers.

(Prior Art) FIG. 6 is a diagram showing the entire system of a multi-view fire detection device (pending application as Japanese Patent Application No. 237066/1986).
Optical signals from three fire detection directions 101 are sent to a photoelectric conversion/amplification section for each detection direction by an optical fiber head 102 composed of three optical fiber light guide sections and a relay optical fiber cable 22. 1, and each wavelength of visible + near-infrared wavelength and infrared wavelength is converted into an electrical signal. A total of six converted signals are sent to an analog-digital (A/D) converter 10 via a multiplexer 105.
After being converted into a digital signal, the frequency discriminator 107 selects the frequency component of interest (for example, 50 to 300) of the temporally fluctuating fire emission intensity.
Hertz) only. The signal extracted by the frequency discrimination unit 107 is sent to the fire determination unit 108, where it is compared with the value stored in the fire determination setting value storage unit 112, and outputs whether the fire is ignited or extinguished. is sent from the output unit 109.

FIG. 7 is a detailed view of the optical fiber head 102, in which three optical fibers 117 are arranged so as to hold their tips in a three-dimensional direction.
The three optical fibers are put together and connected to the photoelectric converter/amplifier 1 as a three-core optical fiber cable 22.

The present invention relates to an improvement in the connection portion of the multi-core optical fiber cable 22 to the photoelectric conversion/amplifier 1. The conventional one is as shown in Fig. 34.
After dismantling the terminal of the three-core optical fiber cable 22 by about 1 m and shaping it into a single-core optical fiber cable 21, the connector 18 is attached and fixed to the front panel 20 of the photoelectric converter/amplifier 1 using the connector screw 19. It was screwed into the receptacle 17 for a single-type light-receiving element, and connected to the light-receiving surface of the single-type light-receiving element 16. In addition, photoelectric conversion
The amplifier 1 is constructed to be taken in and out of the storage rack 3 by means of a rail 23.

(Problems to be solved by the invention) In the above-mentioned conventional technology, when performing maintenance and inspection of the photoelectric converter/amplifier 1 or checking the optical transmission status of the single-core optical fiber 21, the single-core connector 5
When removing the single-core optical fiber 5, there is a problem in that the end surface (mirror-finished surface) of the single-core optical fiber 21 must be protected from damage. The approximately 1m long section of cable that was dismantled also required protection with a special protector to prevent damage from bending and compression when the photoelectric converter/amplifier was inserted and removed.

(Means for solving the problem) Attach a connector receptacle to the backboard of the container that houses the photoelectric conversion amplifier, attach the composite photodetector and the connector for the photoelectric element to the photoelectric conversion amplifier, and remove the photoelectric conversion amplifier from the container. By inserting and removing the light-receiving element, the connection between the light-receiving element connector and the connector receptacle is broken or completed, and the end surface of the optical fiber in the optical fiber cable is connected to the composite light-receiving element at a predetermined interval. A multi-core connector was provided to connect the tip of the optical fiber cable to a connector receptacle.

(Example) An example of the present invention will be described with reference to FIGS. 1 and 2. FIG. 1 is an overall view of a photoelectric converter/amplifier equipped with a three-core connector according to the present invention, and FIG. 2 is a detailed assembly diagram of the three-core connector section. A multi-view fire detection device has an optical fiber head for fire detection placed near the tip of the burner that burns fuel, extracts the optical signal of a burner fire directly to the outside through an optical fiber, and uses a photoelectric sensor to convert the optical signal into an electrical signal. The system is such that the signal is transmitted through a three-core optical fiber cable 22 up to the converter/amplifier 1.

Photoelectric converters/amplifiers require specially designed optical fiber connectors to convert optical signals into electrical signals.

On the back panel 15 of the storage rack 3, the connector receptacle 9 is located at the position indicated by 30.
It is attached via a positioning spring 10 using a mounting screw. The connector receptacle 9 is given a certain degree of freedom by this spring 10. Each optical fiber housed in the three-core optical fiber cable 22 is connected to the connector body 1.
It is attached and fixed to the three-core ferrule 7 in 1 with an adhesive. Further, the connector main body 11 is attached to the connector receptacle 9 by a connector screw 12. Further, the three-core optical fiber cable is aligned with the positioning pin 13 so that the three optical fibers housed therein are lined up, for example, in the vertical direction.

On the other hand, the composite light-receiving element 6 on the side of the photoelectric converter/amplifier 1 is also set in the light-receiving element receptacle 8 with a positioning protrusion 24 as shown in FIG. When inserted into the rack 3 using the rail 23, since the tip of the light receiving element side receptacle 8 is tapered, it has a structure that allows it to easily fit into the fitting part of the connector side receptacle 9 as it is inserted. There is.

In order to reliably transmit the optical signal transmitted by the optical fiber to the light-receiving element 6, it is necessary to finish the optical fiber end face with a mirror finish at the optical signal exit to prevent diffuse reflection. The best method is to glue and fix it to No. 7 and then polish it. Furthermore, it is necessary to keep the distance between the light receiving element 6 and the light receiving element 6 constant. To do this, the shape of the light-receiving element side receptacle 8 is made to match that of the light-receiving element 6, tolerances are determined, fitting is taken into consideration, and a positioning protrusion 24 is provided on the light-receiving element itself to determine the direction of the light-receiving element. Seat (female) for positioning 24 also on the receptacle 8 for the light receiving element on the other side
Prepare. By connecting the receptacle 8 positioned in this way to the connector-side receptacle 9 fitted with the connector main body 11 to which the ferrule 7 is fixed, the distance between the light receiving element 6 and the tip surface of the optical fiber is set to a predetermined value.

When the optical signal is transmitted to the light-receiving element 6, the optical signal is converted into an electric signal at the exit of the light-receiving element 6, the output is amplified inside the photoelectric converter/amplifier, and then transmitted to the multiplexer.

(Effects of the invention) By implementing the invention, maintenance and inspection of the photoelectric converter/amplifier has become easier, and there is no need to take special consideration to prevent damage to the optical fiber at that time.

[Brief explanation of the drawing]

FIG. 1 is an overall view of a photoelectric converter/amplifier equipped with a three-core connector showing an embodiment of the present invention.
Figure 2 is a detailed view of the 3-core connector in Figure 1, Figure 3 is an overall view of a photoelectric converter/amplifier using a conventional single-core connector, and Figure 4 is the single-core connector in Figure 3. Figure 5 is a detailed diagram of the composite light receiving element, Figure 6 is an overall system diagram of the multi-field fire detection device, and Figure 7 is a detailed diagram of the multi-field optical fiber head in Figure 6. It is. 1...Photoelectric conversion amplifier, 2...3-core connector,
3...Photoelectric conversion amplifier storage rack, 6...Composite light receiving element, 7...3-core ferrule, 8...Receptacle for light receiving element, 9...Receptacle for connector, 11...Connector body, 12...Connector Screw, 13... Positioning pin, 15... Back panel, 20... Front panel, 22... Tri-core optical fiber, 23... Rail, 24... Positioning protrusion.

Claims (1)

[Scope of utility model registration request] An optical fiber cable consisting of multiple optical fibers sends the optical signal from a multi-field optical fiber head that receives the optical signal of a burner fire to a photoelectric conversion amplifier, and converts the optical signal from the optical fiber cable into an electrical signal. In the photoelectric conversion amplifier of a multi-view fire detection device equipped with a photoelectric conversion amplifier for amplification, there is a connector receptacle attached to the back board of the container housing the photoelectric conversion amplifier, and a photoelectric conversion amplifier attached to the photoelectric amplifier together with a composite light receiving element. A light-receiving element receptacle that is connected to the connector receptacle when stored in a container and disconnected from the connector receptacle when pulled out from the container, and a composite light-receiving element that connects the end surface of the optical fiber in the optical fiber cable. 1. A photoelectric conversion amplifier for a multi-view fire detection device using an optical fiber, characterized in that a multi-core connector is provided for joining the tip of an optical fiber cable to the connector receptacle so as to be connected at a predetermined interval to the connector receptacle.