JPH0440402A - Device for hardening adhesive for assembling optical connector - Google Patents

Abstract

PURPOSE:To allow the execution of secure and stable adhesion in a short period of time by mounting a ferrule in which an optical fiber is fixed by packing an adhesive via a jig to a metallic conductor by using the heat from the metallic conductor embedded into an electric heater. CONSTITUTION:The electric heater is used as a heat source and the metallic conductor 2 is embedded into the heater 1 by partly exposing the tip of the conductor. A mounting member 3 which locally fixes only the prescribed point of the ferrule 9 to be cured is mounted to the exposed outer periphery of he metallic conductor 2. The heater part 1 as well as the metallic conductor 2 and the mounting member 3 are thermally shielded by the upper part and a shielding plate 5 and a heat control function device which maintains always the specified temp. is added. Then, the ferrule mounting member 3 is directly heated via the metallic conductor 2 of good heat conduction from the heater part 1 and the prescribed point of the ferrule 9 which is a body to be heated is heated and cured at the specified temp. The heating and curing are securely executed in a short period of time.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to an adhesive hardener used in assembling an optical lid used to connect optical fibers.

[Conventional technology]

When connecting an optical fiber to another optical fiber or a light emitting/receiving element, a cylindrical optical connector ferrule (hereinafter referred to as a ferrule) made of metal or ceramics is attached to the tip of the optical fiber to reinforce the optical fiber. be done.

A method for attaching such a ferrule to an optical fiber section is to apply an adhesive to the fiber section, insert it into the ferrule, and then heat and harden the adhesive to fix the adhesive.

Normally, in order to accelerate the curing of the adhesive, it is often used at a temperature higher than room temperature.For example, if the adhesive is epoxy-based 353ND made by Ebotisoku, it is heated to 100-150℃ to cure it in a short time. There is a need to. For this reason, heating methods have been carried out using temperature control, such as housing the device in an oven or installing it in a dedicated heater using a heating heater and a ferrule mounting jig.

[Problem to be solved by the invention]

However, the former method has the disadvantage that the long fiber attached to the ferrule must be inserted into the heating device, which further increases the size of the device.

On the other hand, even if you use a dedicated heater for the latter, it takes time to fix the ferrules to the mounting jig, and when multiple ferrules are installed, it may not be possible to set a stable temperature, resulting in poor adhesion such as variations in adhesive strength and curing time. There was a problem that caused

[Means to solve the problem]

The present invention was developed in view of the above circumstances, and its purpose is to provide a simple optical connector heater that can firmly heat and harden an optical fiber in a short period of time since the optical fiber is installed and fixed within the ferrule using an adhesive. It's about doing.

That is, an electric heater is used as a heat source, the tip of a metal conductor is embedded in the heater with a portion exposed, and a mounting member is attached to the outer periphery of the exposed metal conductor to locally fix the ferrule at a predetermined location. , an optical connector curing device characterized in that the heater part, the metal conductor, and the mounting member are thermally shielded by an upper part and a shielding plate, and a heat control function circuit is added to keep the temperature constant. It is.

In the above, if heating is performed locally only at predetermined locations on the ferrule, not only is the work easier, but also damage to the optical fiber due to heat is prevented.

[For production]

In the present invention, the ferrule mounting member is directly heated from the heater part via a metal conductor with good thermal conductivity, and a predetermined part of the ferrule, which is an object to be heated, can be heated and hardened at a constant temperature, so that it can be heated quickly. Moreover, stable curing can be achieved.

〔Example〕

The present invention will be explained in detail below using examples.

FIG. 1 shows an optical connector heater showing an embodiment of the present invention. In the figure, 1 is a heater part, 2 is a metal conductor, and 3 is a heater part.
4 is a ferrule holding jig, 4 is a ferrule holding plate, 5 is a heat shielding plate, 6 is a support stand, 7 is a heater heating power source and a temperature control unit, and 8 is a temperature detection element.

Next, to specifically explain the curing method using this curing device, the temperature of the ferrule holding jig 3 is determined in advance by the heating power source and the control unit 7, and the temperature of the ferrule holding jig 3 is determined by the (Not shown in Figure 1)
The temperature is maintained at a predetermined temperature, for example, 120°C. Next, the shielding plate 5 is removed in this state, and the fiber 10, which is the object to be heated, is inserted, as shown in FIG.
A ferrule 9.9 filled with adhesive is attached to the ferrule mounting jig 3. The remaining fibers 10, 10 attached to the ferrules 9, 9 are led out via the optical fiber guide section 11. In order to facilitate the work, the ferrule holding jig 3 is provided with a U-shaped groove 12, 12 and a holding plate 4 to prevent the mounted ferrule 99 from slipping backward at the same time as it is mounted and fixed. Furthermore, this U-shaped groove 1
An effective method is to simply fix the optical fiber by coating or pasting an adhesive material 12 on the surface of the optical fiber guide plate 11 so that the optical fiber can be guided accurately to the optical fiber guide plate 11.

Now, after installing the ferrule 9 in this way, the shielding plate 5
is returned to the predetermined position and the area around the ferrule 9 is thermally isolated from the outside. Then, the adhesive is cured using a predetermined combination of the curing temperature of the adhesive used and the load time. For example, in the case of Evokin adhesive from Epotec, 12
2 minutes at 0°C is required.

After curing is completed, the heat shield plate 5 is removed again, and the ferrule 9 is held down and removed from the jig 3. In this case as well, the optical fiber 10 can be easily removed by using the adhesive 12 applied to the surface of the optical fiber guide section 11.

According to the above method, heating a predetermined location of a plurality of ferrules 9.9 has the advantage that the entire ferrule has a uniform temperature, and the adhesive filled in the ferrule can perform a chemically stable curing action. be. Furthermore, as shown in FIG. 3 as a typical example of the operation of the curing device according to the present invention, it takes only about 3 minutes from the time the power is turned on to reach the desired temperature, here set at 120°C. It can be seen that the ambient temperature thereafter is also extremely stable.

The time it takes for the sample to reach a temperature of 120'C after putting the ferrule into such an optical connector curing machine is the same as the standard FOI specified in JI SC5970.
Approx. 30 for ferrules for single-core optical fiber connectors
The temperature is about 10 to 20 seconds, which is sufficiently short to reach 80° C., which is the temperature required to start a chemical reaction. Words that can move the cent amplifier and sample of this hardening device in a short time,
It can be a very effective root during on-site assembly both in factories and especially outdoors.

Here, an ordinary soldering iron is used as the heater serving as the heat source, and a round rod made of copper is processed and embedded inside the heater as the metal conductor.

In addition, in order to investigate the adhesion between the optical connector and the ferrule using this curing device, the bare fiber 13 was placed with a very small protrusion from the tip of the ferrule 9 as shown in FIG.
The change in the protruding view Δe with respect to temperature load was evaluated.

As a result, we conducted 100 cycles of heat shock tests (one cycle is -30°C/+80°C for 1 hour) in which -30"C and +80°C were repeated every 30 minutes.
Among the 20 samples, the variation in the fiber protrusion amount Δp was extremely small, with an average of 0.02 μm and a maximum of +0°07 μm, confirming that stable adhesive fixation could be achieved.

C. Effects of the Invention] As described above, according to the present invention, in curing the adhesive of a ferrule in which an optical fiber is filled with adhesive and fixed, a heat source is obtained from a metal conductor embedded in an electric heater,
By attaching the ferrule to this metal conductor via a jig, there is an advantage that strong and stable adhesion can be achieved in a short time, and furthermore, it can be easily operated and manufactured at low cost.

[Brief explanation of drawings]

Fig. 1 is a configuration diagram of a curing device showing one embodiment of the present invention;
The figure is an enlarged view of the part where the sample ferrule is attached to the hardener in Figure 1, Figure 3 is a diagram showing the relationship between the typical set temperature and time of this hardener, and Figure 4 is a diagram showing the relationship between the typical set temperature and time of this hardener. A diagram showing the amount of fiber protrusion Δβ of a hardened ferrule is shown. ...Heater...Metal conductor...Mounting parts, shielding plate...Control panel and above Applicant: Seiko Electronic Industries Co., Ltd. Patent attorney: Keisuke Hayashi 2nd Th] Haruma (minutes) △Figure 4

Claims (1)

[Claims] A metal conductor is embedded in the electric heater with its tip partially exposed, and a mounting member is attached to the outer periphery of the exposed metal conductor to locally fix the ferrule at a predetermined location, and the heater portion and the An adhesive for assembling an optical connector, comprising a heating section in which exposed metal conductors and the mounting member are covered with a shielding plate, and a control panel having a power supply to the heating section and a heat control circuit. hardener.