JPH0719967A - Optical fiber temperature sensor - Google Patents

Abstract

PURPOSE:To provide a temperature sensor, which can detect the temperature under the electrically insulated condition and which can facilitate the work for installing a sensor. CONSTITUTION:An optical fiber temperature sensor is connected to a terminal 1 such as a high voltage terminal, which is fitted to a terminal board 2, thermally, and deformed by the temperature change. This optical fiber temperature sensor is formed of a detector 3 made of bimetal, shape memory alloy or shape memory resin or the like and sensors made of optical fiber 4 (light transmitting circuit and light receiving circuit) for detecting the deformation of the detector 3 due to the temperature change as shading or the light, transmitted by the optical fiber.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a temperature sensor using an optical fiber, and more particularly to a temperature sensor for detecting abnormal overheating of terminals fastened to a terminal block such as electric wiring, especially high voltage terminals. .

[0002]

2. Description of the Related Art In a terminal block used for electrical wiring,
Poor contact between terminals due to insufficient tightening, rust, vibration, etc. Due to such a poor contact between the terminals, sparks or the like may fly between the terminals and overheat, which may damage the terminals and the terminal block, and may cause a serious accident such as a fire. On the other hand, measures are taken to detect an abnormal place through regular inspections. Further, for continuous monitoring, it has been proposed to detect a temperature rise using a thermistor.

[0003]

However, in the temperature sensor using the thermistor, it is necessary to use one terminal, so that if the number of terminals is large, there is a disadvantage that wiring and installation for the sensor will be troublesome. In addition, since the thermistor itself uses electricity, electrical insulation between the terminals to be ratio-detected becomes a problem, especially in a place handling high voltage.

The present invention has been made based on the above background, and an object of the present invention is to provide a temperature sensor which can perform detection in an electrically insulated state and which is easy to install the sensor. It is to be.

[0005]

The above-mentioned problems can be solved by the present invention. That is, the optical fiber temperature sensor of the present invention is thermally connected to a terminal such as a high voltage terminal and deforms due to a temperature change, and a detector made of a bimetal, a shape memory alloy, a shape memory resin, or the like, and a detection due to a temperature change. It is characterized in that the temperature change of the terminal is detected, which comprises an optical fiber detection means for detecting the deformation of the child as a change of the transmitted light of the optical fiber.

[0006]

The optical fiber temperature sensor of the present invention having the above construction operates and acts as follows. A detector that thermally connects with terminals such as high voltage terminals when they are poorly tightened, rusted, vibrated, etc., causing contact failure and overheating due to sparks between the terminals. However, since it is made of bimetal, shape memory alloy, shape memory resin, or the like, it deforms due to temperature change. Deformation of the detector due to temperature change causes a change in transmitted light of the optical fiber, for example, light blocking, light leakage, light amount change, and optical mode change, and the optical fiber detection means detects this change and detects a temperature change at the terminal. To detect.

[0007]

EXAMPLES The present invention will be specifically described with reference to the following examples. FIG. 1 is a schematic view showing an embodiment of an optical fiber temperature sensor according to the present invention. The optical fiber temperature sensor of this aspect is thermally connected to the terminal 1 such as a high-voltage terminal attached to the terminal block 2 and deforms due to a temperature change,
A detector 3 made of a bimetal, a shape memory alloy, a shape memory resin, or the like, and a sensor (a light transmitting circuit and a light receiving circuit) of an optical fiber 4 for detecting the deformation of the detector due to a temperature change as a shield of the transmitted light of the optical fiber. Consists of. In this sensor, as shown by the broken line in FIG. 1 (A), the detector 3 is deformed by the temperature and shields light, so that this is detected to detect overheating of the terminal.

The present invention is not limited to the above embodiment, but various modifications are possible. For example, as shown in FIG. 2A, pressure is applied to the optical fiber due to deformation of the detector to detect loss of transmitted light of the optical fiber and detect overheating of the terminal. Further, as shown in FIG. 2B, the optical fiber can be cut by the deformation of the detector, and the light blocking can be detected to detect the overheat of the terminal.

Further, as shown in FIG. 3 (A), the detector 3 is housed in an enclosure having an optical fiber insertion hole, the optical fiber is inserted, and this is inserted as shown in FIG. 3 (B). It can also be installed on each terminal 1. Further, as shown in FIG. 3C, a plurality of detectors 3 can be housed in one housing and installed in each terminal 1.

[0010]

As demonstrated by the above embodiment, the present invention has the following effects. Detection can be performed in an electrically insulated state, and the work for installing the sensor is simple.

[Brief description of drawings]

FIG. 1 is a schematic view for explaining an embodiment of a temperature sensor according to the present invention.

FIG. 2 is a schematic diagram for explaining another embodiment of the temperature sensor according to the present invention.

FIG. 3 is a schematic view for explaining another embodiment of the temperature sensor according to the present invention.

[Explanation of symbols]

 1 terminal 2 terminal block 3 detector 4 optical fiber

Claims (3)

[Claims] 1. A terminal comprising: a detector thermally connected to the terminal and deformed by a temperature change; and an optical fiber detection means for detecting a deformation of the detector due to a temperature change as a change in transmitted light of the optical fiber. An optical fiber temperature sensor characterized by detecting a temperature change. 2. The optical fiber temperature sensor according to claim 1, wherein the terminal is a high voltage terminal. 3. The optical fiber temperature sensor according to claim 1, wherein the detector deformable due to temperature change is made of bimetal, shape memory alloy or shape memory resin.