JP2554591Y2 - Mounting structure of optical fiber type sensor - Google Patents

Description

[Detailed description of the invention]

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a mounting structure of an optical fiber type sensor used for mounting an optical fiber type sensor for measuring a temperature using scattered light in an optical fiber on a fixed object side.

[0002]

2. Description of the Related Art In a temperature measuring apparatus using an optical fiber type sensor (hereinafter also referred to as a "distribution type sensor" as appropriate) for measuring a temperature using scattered light in an optical fiber,
An optical pulse is injected into the optical fiber, and the temperature distribution along the optical fiber is measured from the intensity and the arrival time of the backscattered light.

In order to accurately measure the temperature of the device under test, it is necessary to make the temperature uniform between the optical fiber serving as the measuring section and the device under test and to protect the optical fiber usually made of quartz from the outside. In order to achieve both, the coating method and the mounting method are important factors.

Conventionally, an optical fiber is covered and fixed with a material such as a metal having good heat conductivity, or is fixed to an object to be measured as a structure in which the optical fiber is inserted as a sheath.

When the temperature is relatively low, a method such as bonding is used, and when the temperature is high, a mechanical fixing method such as welding or screws is used.

[0006]

However, the above-mentioned conventional mounting structure has the following problems.

That is, in most cases, the object to be measured is also a manufacturing facility in some plant,
Various control devices, electric wiring, and various pipes are installed, and regular or irregular inspection and construction work is generally performed for maintenance and repair of the plant.

At this time, since the measuring optical fiber mounted on the surface of the object to be measured often intersects with the various devices, it is necessary to remove the optical fiber for inspection work.

However, in the conventional mounting structure, the optical fiber cannot be easily removed by any of the methods. Therefore, even if an adhesive having a low adhesive strength is used, the optical fiber is not re-installed. Must be repeated again.

In view of the above circumstances, the present invention makes it possible to easily and accurately attach and detach a delicate optical fiber for measurement to and from an object to be measured and to maintain thermal uniformity. It is an object of the present invention to provide a mounting structure for a type sensor.

[0011]

In order to achieve the above-mentioned object, the present invention uses an optical fiber type sensor for measuring an item to be measured by attaching an optical fiber type sensor to an object to be measured. In the measuring device, a pedestal fixed to the object to be measured and provided over substantially the entire length of the optical fiber sensor, a groove continuously provided in the axial direction of the pedestal, And a cover that is detachably attached to cover and is formed on a part of the cover,
And a projection having an optical fiber embedded therein and having a shape engaging with the groove.

[0012]

According to the above construction, when the cover is fixed to the pedestal, the protrusion of the cover is embedded in the groove of the pedestal, so that the optical fiber embedded in the protrusion can be securely connected to the pedestal. At a predetermined position. Also,
When the optical fiber is removed from the pedestal, the delicate optical fiber can be easily and accurately removed by removing the cover from the pedestal.

[0013]

FIG. 1 is a perspective view showing an example of a sensor fixing device to which a first reference example of a mounting structure of an optical fiber type sensor according to the present invention is applied.

The sensor fixing device shown in FIG. 1 is a long rod-like member fixed around the DUT 1 so as not to straddle a pipe 2 attached around the DUT 1 to be measured such as a tank. 2, and a cover 4 composed of a longitudinal member detachably provided on the open surface 3b side of the pedestal 3 as shown in FIG.

The pedestal 3 is made of a material having a high thermal conductivity such as aluminum or stainless steel, and an optical fiber cable in which a coated optical fiber 5 is covered by a sheath 6 having good thermal conductivity is provided at the center. A round hole 9 having a diameter slightly larger than the diameter of the optical fiber cable 7 is formed, and a groove 10 having a width substantially equal to the diameter of the optical fiber cable 7 is formed from the round hole 9 toward the open surface 3b. Further, steps 11a and 11b are formed on each of the side surfaces 3d and 3e to lock the front end of the cover 4.

When the optical fiber cable 7 is attached to the DUT 1, the portion of the base 3 facing the DUT 1 (fixed surface 3a) is welded prior to the installation of the optical fiber cable 7. Alternatively, the optical fiber cable 7 is fixed to the DUT 1 by an adhesive or the like, and then the optical fiber cable 7 is pushed into the groove 10 so that the optical fiber cable 7 is housed in the round hole 9.

The cover 4 is a member having a U-shaped cross section made of a porous material made of a material such as plastic or inorganic material. Claws 12a and 12b that engage with the step portions 11a and 11b are formed.

After the optical fiber cable 7 is pushed into the round hole 9 of the pedestal 3, the optical fiber cable 7 is pressed against the open surface 3b of the pedestal 3 to form a claw 12a formed at the tip of the side portions 4a, 4b. , 12b correspond to each side surface 3 of the base 3.
Each of the steps 11a and 11b formed at d and 3e is patch-engaged and integrated with the pedestal 3.

In this case, the optical fiber cable 7 for detection is used.
Is covered by a pedestal 3 composed of a good thermal conductor, and the size of the pedestal 3 is formed to be about two to three times the heat capacity of the optical fiber cable 7. The temperature of the optical fiber cable 7 and the temperature of the DUT 1 can be made substantially the same.

Further, since the opposite side of the joint surface with the DUT 1 is covered with a member having a small heat conduction, that is, a member having a so-called heat insulating effect, heat loss to the outside and inflow of heat from the outside are minimized. As a result, the temperature of the DUT 1 can be accurately measured.

Further, since the cover 4 is detachably attached to the pedestal 3 by the claws 12a and 12b and can be easily removed, the optical fiber cable is used for removing the pipe 2 and the like from the DUT 1. When the obstruction 7 is in the way, the cover 4 is removed from the pedestal 3 and the optical fiber cable 7 housed in the pedestal 3 is detached. Can be achieved.

As described above, in the reference example, the pedestal 3 is fixed to the DUT 1 and the round hole 9 formed in the pedestal 3 is formed.
The optical fiber cable 7 for measurement can be easily detached from the DUT 1 because the optical fiber cable 7 is removably housed in the inside and covered with the removable cover 4. Uniformity can be maintained.

FIG. 3 is a sectional view showing an example of a sensor fixing device to which a second reference example of the mounting structure of the optical fiber type sensor according to the present invention is applied. In this figure, the same parts as those shown in FIGS. 1 and 2 are denoted by the same reference numerals.

The sensor fixing device shown in this figure is different from the device shown in FIGS. 1 and 2 in that the depth of the groove 10 formed in the open surface 3b of the pedestal 3 is increased to form the sensor fixing device in the pedestal 3. The round hole 9 is made closer to the fixing surface 3a side, so that the air in the groove 10 becomes a heat insulating layer and the cover 4 is eliminated.

In this case as well, the optical fiber cable 7 for measurement can be easily detached from the DUT 1 and the thermal uniformity can be maintained as in the first embodiment. In addition, the manufacturing cost and installation cost of the entire apparatus can be reduced and the construction can be facilitated by the amount of eliminating the cover 4.

FIG. 4 is a sectional view showing an example of a sensor fixing device to which the first embodiment of the mounting structure of the distributed sensor according to the present invention is applied. In this figure, FIGS. 1 and 2
The same reference numerals are given to the same parts as those shown in FIG.

The difference between the sensor fixing device shown in this figure and the device shown in FIGS. 1 and 2 is that a shallow long groove 15 is formed in the open surface 3b of the pedestal 3, and the inner surface of the cover 4 that covers the open surface 3b. The optical fiber cable 7 can be installed simply by forming a long protrusion 16 having a shape corresponding to the shape of the groove 15 and embedding the optical fiber cable 7 in the long protrusion 16 and attaching the cover 4 to the pedestal 3. Further, the optical fiber cable 7 can be removed from the pedestal 3 simply by removing the cover 4 from the pedestal 3.

As described above, according to this embodiment, the delicate optical fiber cable 7 for measurement can be easily attached to and detached from the DUT 1 and the thermal uniformity can be maintained. it can.

FIG. 5 is a sectional view showing an example of a sensor fixing device to which a second embodiment of the distributed sensor mounting structure according to the present invention is applied. In this figure, FIGS. 1 and 2
The same reference numerals are given to the same parts as those shown in FIG.

The sensor fixing device shown in this figure is different from the device shown in FIGS. 1 and 2 in that a rectangular long groove 17 is formed in the open surface 3b of the pedestal 3, and an optical fiber is formed in the lower part of the long groove 17. A recess 18 having a diameter slightly larger than the diameter of the cable 7 is formed. Further, a rectangular cover 4 having a cross section corresponding to the shape of the long groove 17 is formed, and a portion of the cover 4 corresponding to the recess 18 is formed. A long projection 19 is formed, the optical fiber cable 7 is embedded in the long projection 19, and the cover 4 is pushed into the long groove 17 of the pedestal 3,
The optical fiber cable 7 can be installed only by inserting the long protrusion 19 of the cover 4 into the concave portion 18 of the pedestal 3, and the optical fiber cable can be installed from the pedestal 3 simply by removing the cover 4 from the pedestal 3. 7 can be removed.

By doing so, the first
As in the embodiment, the optical fiber cable 7 for measurement can be easily attached to and detached from the DUT 1, and the thermal uniformity can be maintained.
The formation of the cover 4 can be facilitated by eliminating the a and 12b, and the connectivity between the cover 4 and the pedestal 3 can be improved.

FIG. 6 is a sectional view showing an example of a sensor fixing device to which the third embodiment of the distributed sensor mounting structure according to the present invention is applied. In this figure, FIGS. 1 and 2
The same reference numerals are given to the same parts as those shown in FIG.

The sensor fixing device shown in this figure differs from the device shown in FIGS. 1 and 2 in that the width of the groove 10 formed in the open surface 3b of the pedestal 3 is the same as that of the round hole 9 formed in the pedestal 3. When the optical fiber cable 7 is set in the groove 10, a "U" -shaped spring member 20 whose diameter is substantially the same as that of the optical fiber cable 7 and whose open surface is narrowed in the groove 10 is provided at predetermined intervals. The elasticity of the member 20 facilitates the insertion of the optical fiber cable 7 and makes it difficult to remove the cable.

In this manner, similarly to the first embodiment, the optical fiber cable 7 for measurement can be easily detached from the DUT 1, and the air layer in the groove 10 is used as a heat insulating layer. As a result, the heat insulating material such as the cover 4 is not required, whereby the manufacturing cost and installation cost of the entire apparatus can be reduced and the construction can be facilitated by the amount of the cover 4 unnecessary.

In each of the above-described embodiments and reference examples, the shape of the pedestal 3 is determined according to the outer peripheral shape of the DUT 1. However, as shown in FIG. Cuts 21 are made at predetermined intervals in the longitudinal direction on the surface 3b side, and even if the outer peripheral shape of the DUT 1 is a curved surface, it is attached to the outer surface of the DUT 1 with one kind of pedestal 3. You may be able to do it.

[0036]

As described above, according to the present invention, a delicate optical fiber for measurement can be easily and accurately attached to and detached from an object to be measured, and thermal uniformity can be maintained. Can be.

[Brief description of the drawings]

FIG. 1 shows a first embodiment of a mounting structure of a distributed sensor according to the present invention.
It is a perspective view showing an example of a sensor fixing device to which a reference example is applied.

FIG. 2 is a sectional view showing an example of a sectional structure of the sensor fixing device shown in FIG.

FIG. 3 shows a second embodiment of the mounting structure of the distributed sensor according to the present invention.
It is sectional drawing which shows an example of the sensor fixing device to which the reference example is applied.

FIG. 4 shows a first embodiment of the mounting structure of the distributed sensor according to the present invention.
It is sectional drawing which shows an example of the sensor fixing device to which an Example is applied.

FIG. 5 shows a second embodiment of the mounting structure of the distributed sensor according to the present invention.
It is sectional drawing which shows an example of the sensor fixing device to which an Example is applied.

FIG. 6 shows a third example of the mounting structure of the distributed sensor according to the present invention.
It is sectional drawing which shows an example of the sensor fixing device to which the reference example is applied.

FIG. 7 is a partial perspective view showing a modified example of the mounting structure of the distributed sensor according to the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 DUT 2 Piping 3 Pedestal 4 Cover 7 Optical fiber cable (distributed sensor)

Claims (1)

(57) [Scope of request for utility model registration] 1. A measuring apparatus using an optical fiber type sensor for measuring an item to be measured of the object to be measured by attaching the optical fiber type sensor to the object to be measured, wherein the optical fiber type sensor is fixed to the object to be measured, A pedestal provided substantially over the entire length of the sensor, a groove continuously provided in the axial direction of the pedestal, a cover removably attached to the pedestal so as to cover the groove, and And a protruding portion formed in a part of the optical fiber and engaged with the groove, and having an optical fiber embedded therein.