JP2542365Y2 - Heat shrink tube heater for optical fiber reinforcement - Google Patents

Description

[Detailed description of the invention]

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a heating device for a heat-shrinkable tube in a reinforcing method using a heat-shrinkable tube for reinforcing a fusion spliced portion of an optical fiber.

[0002]

2. Description of the Related Art In FIG. 2, reference numeral 10 denotes a heater plate which has the shape of an elongated square plate. 20 is a heat conductor. It is made of metal such as aluminum. The heater plate 10 is fixedly attached to both ends. It is thermally connected to the heater plate 10 so that the heat of the heater plate 10 flows into and dissipates outside.

Since the heat conductor 20 removes heat at both ends of the heater plate 10, the temperature distribution in the longitudinal direction of the heater plate 10 has a mountain shape with both ends lowered as shown in the lower part of FIG. When the heat conductor 20 is not attached, the temperature distribution becomes almost flat like a dashed line.

A round heat-shrinkable tube 40 passing through a connection portion of the optical fiber 30 is placed on the heater plate 10 and shrunk. At this time, since the temperature distribution of the heater plate 10 is higher at the center as described above, the heat shrinkage starts from the center of the tube 40 and moves outward sequentially. Therefore, the air inside is naturally expelled with the contraction of the heat-shrinkable tube 40.

[0005] If the heat conductor 20 is not provided, the temperature distribution in the longitudinal direction of the heater plate 10 becomes substantially flat as described above. Then, the air is trapped inside and an air pocket is formed.

If this air pocket exists near the optical fiber, a force is applied to the optical fiber during repeated expansion and contraction due to a change in the outside air temperature, and the optical fiber is eventually broken.

[0007]

In the conventional case, the heat conductor 20 is fixed to the heater plate 10, and the length of the heater plate 10 is constant. Therefore, the temperature distribution in the longitudinal direction is also constant. There is no problem if the heat-shrinkable tube 40 having the same length is always used.

However, there are cases where a shorter heat shrink tube 40 must be used. In this case, as shown in FIG. 3, the heater plate 10 is heated only at a substantially flat portion of the temperature distribution substantially at the center. Therefore, there is a possibility that air pools may be generated in the heat-shrinkable tube 40.

[0009]

As shown in FIG. 1, one or both of the heat conductors 20 can be moved in the longitudinal direction of the heater plate 10.

For this purpose, for example, the heat conductor 20 is slidable on the rail 52 of the base 50 (FIG. 1).
(B)) The screw 54 can be moved forward and backward.
The screw 54 is rotated manually or by a motor. 56
Is a nut. Further, the heat conductor 20 is provided with a lateral hole 22 so that the heater plate 10 can enter and exit while contacting the inner surface of the lateral hole 22 when the heat conductor 20 moves. Note that both heat conductors 20 may be movable.

[0011]

FIG. 1A shows a heat-shrinkable tube 40.
Is a standard length, and the heat-shrinkable tube 40 can be thermally shrunk in the same manner as in the conventional case of FIG.

When the heat-shrinkable tube 40 is short, FIG.
As shown in (c), the heat conductor 20 is moved and the heater plate 1 is moved.
The substantial length of 0 is shortened. Then, the temperature distribution of the heater plate 10 becomes as shown in the figure (there is no flat portion at the center), and the heat shrinkage starts from the center of the heat shrinkable tube 40. Therefore, air cannot be trapped in the heat-shrinkable tube 40. As described above, one heater can accommodate the heat-shrinkable tubes 40 having different lengths.

[Brief description of the drawings]

FIG. 1 is an explanatory view of an embodiment of the present invention, wherein (a) shows a case where a heater plate 10 is lengthened, (b) shows a B sectional view of (a),
(C) shows a case where the heater plate 10 is shortened.

FIG. 2 is an explanatory diagram of a conventional technique.

FIG. 3 is an explanatory diagram of a problem to be solved in the invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 10 Heater plate 20 Heat conductor 22 Side hole 30 Optical fiber 40 Heat shrinkable tube 50 units 52 Rail 54 Screw 56 Nut

Claims (1)

(57) [Scope of request for utility model registration] 1. A heater for a heat-shrinkable tube for reinforcing an optical fiber, wherein heat conductors are provided on both sides in the longitudinal direction of an elongated heater plate so that the temperature distribution at both ends of the heater plate is lower than that at the center. A heater for a heat-shrinkable tube for reinforcing an optical fiber, wherein one or both of the heat conductors can be moved in the longitudinal direction of the heater plate.