JPS6275220A - Abnormal temperature detector - Google Patents

Abstract

PURPOSE:To accurately detect temperature abnormality of an objective member to be measured even if the coating or the like is performed on the objective member to be measured by providing a shape memory alloy member to move a shielding plate from the 1st position to the 2nd position at the time of the abnormal temperature. CONSTITUTION:Abnormal temperature detectors 21, 31 and 41 using the shape memory alloy member are connected in series by an optical fiber 50 and fixed on a part of a bus bar properly. Further, a transmission part 52 and a power source 51 are connected with the optical supply side of the optical fiber 50. Then, rays of light from a light source included in the transmission part 52 enter the detectors 21, 31 and 41 through the optical fiber 50. On the other hand, an optical conversion means 61 of a reception part 60 connected with the other end of the optical fiber 50 converts the given rays of light into an electrical signal via the detectors 21, 31 and 41 and gives it a decision circuit 62. Then, in case one of the detectors 21, 31 and 41 detects the abnormal temperature, since the detectors 21, 31 and 41 are connected in series, the rays of light are intercepted and does not reach the optical conversion means 61. Consequently, the decision circuit 62 can discriminate the occurrence of the abnormal temperature by the presence or absence of the electrical signal from the conversion means 61.

Description

Detailed Description of the Invention [Field of Industrial Application] The present invention relates to a device used for detecting abnormal temperatures in a substation busbar, and in particular, to detecting abnormal temperatures using a shape memory alloy member as a detection element. This invention relates to a detection device.

[The day before the invention] In low-voltage substations, from a safety standpoint, in recent years,
Insulating coatings are increasingly being applied around busbars. However, when an insulating coating is applied, it becomes extremely difficult to detect abnormal heating of the connection area due to loosening of bolts, etc. at the connection point of the sysbar.

Therefore, there is a need for a c1 field device that can automatically detect abnormal heating from outside the insulation coating.

SUMMARY OF THE INVENTION It is an object of the present invention to provide an abnormal temperature detection device that can reliably detect temperature abnormalities in a member to be measured, even if the member to be measured is covered with a coating or the like.

[Means for Solving the Problems] The abnormal temperature detection device of the present invention includes first and second optical transmission means arranged opposite each other so as to be able to transmit and receive light, and the first and second optical transmission means. A shielding means provided so as to be movable between a first position that does not block the exchange of light between the means and a second position that blocks the exchange of light between the first and second optical transmission means. and a shape memory alloy member that moves the shielding means from the first position to the second position when the temperature is abnormal.

[Function] In the abnormal temperature detection device of the present invention, the light transmitted and received between the first and second optical transmission means is blocked by the shielding means moved by the shape memory alloy member in the event of an abnormality, thereby preventing the measurement object from being detected. abnormal conditions may be detected. By the way, the transformation point of a shape memory alloy member can be changed by slightly changing its composition. Therefore, settings can be made such that abnormal temperatures can be detected within a wide temperature range.

Furthermore, since the reaction is caused by heat from the member to be measured, temperature abnormalities can be reliably detected even if there is an insulating cover or the like on the surface of the member to be measured on which the detection device is attached.

[Description of Embodiment] FIG. 1 is a sectional view of an embodiment of the present invention, and FIG. 2 is a sectional view taken along the If-TI line in FIG. 1.

The abnormal temperature detection device 1 of this embodiment has an optical fiber 2 as a first optical transmission means and an optical fiber 3 as a second optical transmission means. A rod lens 4.5 is attached to the tip of each optical fiber 2. has been done. rod lens 4
, 5 are provided to convert the light exchanged between them into parallel beams.

Furthermore, as is clear from Fig. 1, the rod lens 4.5
is arranged inside the housing 7 of the abnormal temperature detection device of this embodiment. Similarly, a shape memory alloy member 9 is fixed to the base plate 7a of the housing 7 between the rod lenses 4 and 5, and a shielding plate 6 as a shielding means is fixed to the tip of the shape memory alloy member 9. has been done.

The shielding plate 6 is provided so as to take the first position shown by the solid line in FIG. 2 at all times, that is, when the busbar 10 as the surface to be measured in contact with the housing 7 is at a normal temperature. Further, the shape memory alloy member 9 is subjected to shape memory treatment so that when the surface of the bus bar 10 is at an abnormal temperature, it assumes a second position shown by an imaginary line 16 in FIG.

That is, the movement from this first position to the second position is
This is carried out by transformation of the shape memory alloy member 9 due to temperature changes. Therefore, it is preferable that the base plate 1-7a to which the shape memory alloy member 9 is attached is made of a material as excellent in thermal conductivity as possible. In the second position, the shielding plate 6 blocks light transmission between the rod lenses 4.5.

In this embodiment, the shape memory alloy member 9 and the shielding plate 6 are constructed separately, but the entire shielding means including the shielding plate 6 may be constructed of the shape memory alloy member.

In the embodiment shown in FIGS. 1 and 2, for example, the first
Light is supplied from an optical fiber 2 serving as a light transmission means, converted into a parallel beam by a rod lens 4, and applied to the other rod lens 5. During normal operation, the shielding plate 6 is closed as described above.
Since it is in the first position shown by the solid line in FIG. 2, the transmission and reception of light is carried out without any problem.

On the other hand, if the bus bar 10 as the member to be measured is abnormally heated, the shape memory alloy member 9 is deformed and the shielding plate 6 assumes the second position shown by the imaginary line 16'c in FIG. Therefore, the parallel beam from the rod lens 4 is blocked by the shielding plate and does not reach the other rod lens 5 and thus the optical fiber 3. Therefore, abnormal heating of the bus bar at the other end of the optical fiber 3 can be detected by the presence or absence of light reaching the other end.

Next, an example of an abnormal temperature detection system using the embodiment shown in FIGS. 1 and 2 will be described. FIG. 3 is a schematic block diagram of this abnormal temperature detection system. Here, the abnormal temperature detection device 21 shown in FIG. 1 and FIG.
31 and 41 are connected in series by an optical fiber 50. Each of the abnormal temperature detection devices 21, 31, and 41 is appropriately fixed to a portion of the bus bar to be measured. Therefore, as described above, when the part to be measured is abnormally heated, the light supplied through the optical fiber 50 is blocked.

A transmitting section 52 is connected to the light supply side of the optical fiber 50, and the transmitting section 52 is electrically connected to the power line '&51. The transmitter 52 includes a light source driven by a power source 51, and light from the light source is applied to each abnormal temperature detection device 21, 31, and 41 through an optical fiber 50.

On the other hand, a receiver 60 is connected to the other end of the optical fiber 50. The receiving section 60 includes a photoelectric conversion means 61, a determination circuit 62, and a display device @63.

The photoelectric conversion means 61 connects each abnormal temperature detection device 21, 31.
The light provided through 41 is converted into an electrical signal and provided to a determination circuit 62. In addition, any abnormal temperature detection device 21
, 31.41, when an abnormality '/fA degree is detected, that is, when the bus bar is abnormally overheated at any position, each abnormal temperature detection device 21.31.4
1 are connected in series, the light does not reach the photoelectric conversion means 61. Therefore, the determination circuit 62 determines whether it is safe or not depending on the presence or absence of the electrical signal from the photoelectric conversion means 61.
:, determine the occurrence of degree. The display device 63 displays the occurrence of abnormal temperature based on the electric signal from the determination circuit 62, and is constituted by an appropriate display device such as a 1-piece display device.

By the way, in this abnormal temperature display system, each abnormal temperature detection device N21, 31, 41 uses the shape memory alloy member 9 as described above, so the shape memory alloy member 9 has an irreversible shape memory effect. By using a material that exhibits this, it is also possible to hold the abnormal temperature display.

In the embodiments shown in FIGS. 1 and 2, the shielding means consisted of a shielding plate 6 that was not normally located between the rod lenses 4.5, but as shown in FIG. , when using the shielding plate 76 having the open lower part 1 for transmitting light, also in the first position,
The shielding plate 76 can be positioned between both rod lenses, and therefore the displacement of the shape memory alloy member 79 to which the shielding plate 76 is fixed can be reduced. In addition, in FIG. 4, an imaginary line B indicates the shielding plate 7.
6 is in the second position.

[Effects of the Invention] In the present invention, first and second optical transmission means are arranged facing each other so that light can be exchanged, and during normal operation, light can be exchanged between the first and second optical transmission means. A shape memory device that is disposed at a first position where it does not block light transmission, and which receives heat from the member to be measured and is displaced to a second position where it blocks transmission and reception of light between the first and second light transmission means in the event of an abnormality. Since it is configured to be driven by an alloy member, it is possible to detect whether or not the humidity of the member to be measured is abnormal without using a complicated circuit. Furthermore, since a shape memory alloy member is used, not only can the circuit be simply configured, but the size of the detection device can also be made smaller.

Furthermore, since the transformation temperature of the shape memory alloy member can be controlled by changing the composition, it is possible to obtain an abnormal temperature detection device that can be used over a wide temperature range.

The present invention can be widely applied to detect not only abnormal temperatures of bus bars as explained in the description of the embodiments, but also abnormal temperatures of members and parts in general that are in an overheated or overcooled state.

[Brief explanation of drawings]

FIG. 1 is a sectional view of one embodiment of the present invention, and FIG. 2 is a sectional view taken along line II-n in FIG. 1. FIG. 3 is a schematic block diagram showing an example of an abnormal temperature detection system constructed using the embodiments shown in FIGS. 1 and 2. FIG. Figure 4 shows '! FIG. 7 is a schematic cross-sectional view for explaining another structural example of the M shielding means. In the figure, 1 is an abnormal temperature detection device, 2 is an optical fiber as a first optical transmission means, and 3 is a second optical fiber.
4.5 is a rod lens, 6 is a shielding plate as a shielding means, 9 is a shape memory alloy member, 10 is a bus bar as a member to be measured, 21
．． 31.41 is an abnormal temperature detection device, 76 is a shielding plate as a shielding means, and 79 is a shape memory alloy member. Patent applicant: Sumitomo Electric Industries, Ltd. (and 2 others) - Figure 2, Figure 31

Claims (3)

[Claims] (1) first and second optical transmission means arranged oppositely so as to be able to transmit and receive light; a first position that does not block transmission and reception of light between the first and second optical transmission means; a shielding means provided to move between a second position for blocking transmission and reception of light between the first and second optical transmission means; and a shielding means provided to move between the first position and the second position when the temperature is abnormal. and a shape memory alloy member provided to move the shielding means. (2) The abnormal temperature detection device according to claim 1, wherein the first and second optical transmission means are constituted by optical fibers. (3) The abnormal temperature detection device according to claim 2, wherein a rod lens is attached to an end of the optical fiber on the shape memory alloy member side.