JP3451837B2 - Magnetic type temperature detecting device and electric equipment using the same - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a magnetic temperature detecting device which detects when the temperature of a temperature-measured object reaches a specific temperature with a temperature-sensitive ferrite and transmits it as an optical signal, and an electric device using the magnetic-type temperature detecting device. Regarding equipment.

[0002]

2. Description of the Related Art By using an electrically isolated temperature detecting means without being affected by electromagnetic induction or electrostatic induction,
As a temperature detector for detecting abnormal temperatures of high-voltage cables, current busbars, etc., or the presence or absence of reaching a preset temperature, temperature-sensitive ferrite is used as the temperature detecting means, whose permeability changes widely at the Curie point. Japanese Patent Application No. 6-210327 discloses a temperature detecting means as illustrated in FIG. 10, which detects arrival at the Curie temperature as an on / off signal of light.

In the conventional example of FIG. 10, a casing 1, a temperature-sensitive ferrite 2, a permanent magnet 3, a magnetic yoke 4, and a heat receiving plate 32 also serving as a magnetic yoke, a shaft 5 fixed to the temperature-sensitive ferrite 2, and this shaft 5. A spring 6 that applies a biasing force to push the permanent magnet 3 in the direction opposite to the permanent magnet 3 constitutes a temperature detection unit, and includes a total reflection type reflector 9, a light projecting optical fiber 20, a light receiving optical fiber 21, and a beam. The light switch 7 is constituted by the light shielding plate 7 connected to the shaft 5 via 52.

In FIG. 10, the temperature sensitive ferrite 2 is magnetically attracted to the permanent magnet 3 fixed to the heat receiving plate 32. The magnetic yoke 4 is arranged so that the magnetic flux generated by the permanent magnet 3 is returned to the permanent magnet 3 via the temperature-sensitive ferrite 2. On the shaft 5 fixed to the temperature-sensitive ferrite 2, the temperature-sensitive ferrite 2 is attached to the permanent magnet 3 by a spring 6.
The biasing force acts in the direction of pulling away from. Then, the light shielding plate 7 connected to the shaft 5 via the beam 52
Is an optical fiber for projecting light when the temperature-sensitive ferrite 2 moves away from the permanent magnet 3 and the shaft 5 moves in the direction of the arrow.
It penetrates into the optical path of the optical switch provided between the light receiving optical fiber 21 and the light receiving optical fiber 21, and blocks the signal light. At this time, the upper end portion 51 of the shaft 5 is projected to the outside of the housing 1 of the temperature detecting device so that the operation of the temperature detecting portion can be visually confirmed.

The above-mentioned optical switch is made of a transparent optical member, for example, a transparent resin such as polymethylmethacrylate (PMMA) or polycarbonate (PC) as a material, and the optical fiber 20 for projecting light and the light for receiving light are provided in parallel. fiber
Two reflecting surfaces each having a mounting surface of 21 and arranged so that the light emitted from the light projecting optical fiber 20 enters the light receiving optical fiber 21 after being reflected twice. In the middle of
A total reflection type reflector 9 is formed by forming a U-shaped recess so that the light shielding plate 7 can enter. The curvature and the arrangement position of the two curved reflecting surfaces of the reflector 9 are such that the light emitted from the light projecting optical fiber 20 is reflected by the first reflecting surface of the reflector 9 and the second reflecting surface. The light that has been collected at the midpoint of the U-shaped recess provided in the middle of the surface and is emitted from this midpoint is reflected by the second reflecting surface of the reflector 9 and is received by the optical fiber for receiving light.
It is obtained by calculation based on the law of reflection, provided that it is focused on 21.

When the reflecting surface is molded as described above, the angle of intersection between the normal and the incident ray at the light incident point of the reflecting surface becomes about 45 °, and polymethylmethacrylate (PMM) is used.
Formula (1) for transparent resin materials whose relative refractive index n is about 1.5, such as A) or polycarbonate (PC)
Is greater than the critical angle θ _c (= 41 °). θ _c = sin ^-1 1 / n (1) Therefore, if both reflecting surfaces are processed and formed sufficiently flat compared to the wavelength of the incident light, they will become total reflection surfaces for the incident light, and There is no need to add a special reflector for efficiency.

The magnetic attraction between the temperature-sensitive ferrite 2 and the permanent magnet 3 sharply decreases near the Curie temperature, as shown in FIG. Therefore, as shown in FIG. 11, the operating temperature, that is, the temperature at which the temperature-sensitive ferrite 2 separates from the permanent magnet 3 is set to the Curie temperature by setting the biasing force of the spring 6 between the maximum value and the minimum value of the attraction force. It can be a neighborhood.

With the structure described above, the temperature-sensitive ferrite 2 is separated from the permanent magnet 3 at the operating temperature, that is, the detection temperature, and the light-shielding plate 7 blocks the optical path between the optical fibers and is provided at the opposite end of the light-receiving optical fiber 21. The light receiving element (not shown) detects the change in the amount of received light, and the change in the amount of received light is converted into an electric signal by a switching circuit (not shown) and output as an abnormal temperature detection signal.

The above is the description of the conventional magnetic type temperature detecting device. Next, the electric equipment using the same will be described. FIG. 12 is a perspective view showing a case where a conventional magnetic temperature detecting device is attached to a bus bar to electric device 400 to detect an abnormal temperature of a wiring part. In this case, the bus bar 80 is screwed and the temperature detecting device 110 is directly connected.
Is attached. The temperature detecting device 110, the optical fiber 60, and the electro-optical converter 70 are independently connected to each bus bar, and three sets of devices are used.

In FIG. 12, the bus bar 80 is screwed and the temperature detecting device 110 is attached to the bus bar 80, but the bus bar 80, the terminal board 200, and the temperature detecting device 110 are connected with the terminal screws 201.
It is also possible to tighten and attach together.

[0011]

When the temperature detection target object is a power source busbar of a power equipment control device, the busbars of the same shape are often arranged in parallel at relatively narrow intervals, and a high power consumption is required. Due to the high currents being processed, these busbars can be hot and carry a magnetic field around them.

The magnetic type temperature detecting device used for monitoring the temperature of the temperature detection target object as described above is a total reflection type device which can be mounted in a space having a narrow space and is often made of a transparent resin material. The optical switch, which consists of optical components such as reflectors, has a structure that is isolated from the temperature detection target object that may reach a high temperature.In addition, the temperature detection unit that detects temperature due to changes in magnetic characteristics has a magnetic field around it. It must satisfy the condition that it works properly even in an existing installation location.

On the other hand, the magnetic temperature detecting device based on the prior art described with reference to FIG. 10 does not have a structure satisfying the above conditions, and therefore it is difficult to mount it on bus bars or the like arranged in parallel. Not only is it impossible, but there is a problem that a stable temperature detection operation cannot be ensured when the temperature detection target object becomes hot or when there is a magnetic field around it.

The present invention has been made in view of the above-mentioned problems in the magnetic type temperature detecting device based on the prior art, can be mounted in a space with a narrow interval, and the optical switch portion can reach a high temperature. A magnetic temperature detection device that is isolated from an object whose temperature is to be detected, and the temperature detection part operates normally without being affected by the surrounding magnetic field even in an installation location where a magnetic field exists in the periphery. The challenge is to provide.

The magnetic type temperature detecting device according to the prior art can be attached to the electric equipment only after the electric equipment is installed on the panel and the electric wiring is completed, and when it is directly attached to the bus bar, It was necessary to screw the bus bar. Furthermore, when changing the specifications of the panel, it is necessary to remove the temperature detecting device and then remove the electric wiring, which increases the number of wiring work steps.

A second object of the present invention is to provide an electric device provided with a magnetic type temperature detecting device, which does not require an increase in the steps in the above wiring work.

[0017]

In order to achieve the above object, in the present invention, a heat receiving plate for transmitting the heat of an object to be temperature detected to a temperature sensitive ferrite is formed in a substantially L shape, and one end thereof is attached. The surface is attached to the mounting surface of the temperature detection target object, and the shaft is fixed to the permanent magnet of the temperature detection unit which is the first component of the apparatus, and the optical switch unit which is the other component is a total reflection type. The magnetic temperature detecting device is configured by disposing the reflector and the introducing directions of the light projecting and receiving optical fibers coupled to the reflector in parallel with the mounting surface of the temperature detection target object. There is.

Further, with respect to the mounting surface of the temperature detection target object, the optical switch case accommodating the optical switch part is disposed via the temperature detection part case accommodating the temperature detection part so that the heat of the temperature detection target object is directly In addition, the magnetic field is prevented from being transmitted to the optical switch section, and in addition, a magnetic material is used for the temperature detecting section case that accommodates the temperature detecting section so that a magnetic field around the case does not enter the case.

In the second invention of the present invention, since the temperature detecting device of the present invention can be mounted in a space having a narrow interval and has a structure which is protected both thermally and magnetically,
The temperature detecting device of the present invention is housed in the terminal portion of the electric device. The mounting structure is such that the heat receiving plate of the temperature detecting device is slid on the terminal plate of the electric device and pushed in, so that the heat receiving plate of the temperature detecting device is crimped to the terminal plate of the electric device by a spring. The work is one-touch, easy, and can be installed independently of the wiring work.

Further, in the case of an electric device having a plurality of temperature detecting elements, such as a temperature detecting element for each phase of the polyphase, those temperature detecting devices are connected in series by an optical fiber. A single electro-optical converter enables multi-phase temperature monitoring of electrical equipment.

[0021]

BEST MODE FOR CARRYING OUT THE INVENTION The first invention of the present invention relates to a magnetic temperature detecting device. It can be installed in a narrow space, and the optical switch part is isolated and protected from the temperature detection target object that may reach high temperature.
In order to realize a magnetic temperature detecting device that operates normally without being affected by the temperature detecting portion even in an installation location where a peripheral magnetic field exists, in the present invention, the mounting dimension required in the direction orthogonal to the mounting surface is set. In order to minimize it, the shaft fixed to the permanent magnet and magnetic yoke of the temperature detection part, the total reflection type reflector of the optical switch part, and the introduction direction of the optical fiber for light projection and light reception connected to the reflector However, in order to protect the optical components of the optical switch part thermally by arranging them in parallel to the mounting surface of the temperature detection target object, the Further, in order to block the ambient magnetism from invading the temperature detecting unit, a magnetic type temperature detecting device is constructed by using a magnetic material in the case accommodating the temperature detecting unit. It is.

A second aspect of the present invention relates to an electric device using the magnetic temperature detecting device according to the first aspect of the present invention, wherein a magnetic temperature detecting device according to the present invention is provided at a terminal portion of the electric device. Is provided, and the temperature detecting device is housed therein. As its mounting structure,
The heat receiving plate is attached by crimping, and a plurality of temperature detecting devices are connected in series for signal processing.

Examples will be described below. [First Embodiment of Magnetic Temperature Detector] The first embodiment of the magnetic temperature detector according to the present invention is shown in FIGS. 1 and 2 to explain the present invention. Note that FIG. 1 is a cross-sectional configuration diagram, and FIG. 2 is an explanatory diagram of the optical switch section as seen from above with the upper lid of the temperature detection device removed.

In FIG. 1 and FIG. 2 as well, the elements having the same functions as those in FIG. 10 used in the description of the prior art are designated by the same reference numerals, and the description thereof will be omitted. The temperature detection device illustrated in FIGS. 1 and 2 includes a temperature detection unit 101 disposed on the side where the inside is close to the temperature detection target object 200, and a temperature detection unit 101 adjacent to the temperature detection unit 101 and remote from the temperature detection target object 200. The temperature transmitter 100 divided into two layers of the optical switch unit 102 disposed on the side, and the temperature detecting unit 101 in the temperature transmitter 100 .
And a heat receiving plate 30 that also serves as a support for holding the temperature transmitter 100 itself while transmitting the heat of the temperature detection target object 200 to the.

As the heat receiving plate 30, the mounting screw 36 is used.
Thermally closely attached to the temperature detection target object 200 such as by, with transfer heat of the temperature detection target object 200 to the temperature detection unit 101 of the temperature transmitter 100, temperature transmitter 100
In order to hold the steel plate stably and firmly, a metal plate having a high thermal conductivity such as an iron material having a suitable thickness is formed into an L shape and used. In this way, the base 15 that supports one end of the temperature transmitter 100 can be omitted, and the heat insulation of the temperature detection target object 200 can be improved. Furthermore, the dimensions of the column segment to maintain the temperature transmitter 100 in the heat receiving plate 30, when set larger than the insertion length of the temperature transmitter 100, when fitted with a temperature sensing device to the temperature detection target object 200, temperature transmitter Since there is a space between the housing 1 of the temperature detector 100 and the temperature detection target object 200, the temperature detection target object 200 is connected to the temperature transmitter 100 housing 1
It is possible to prevent the heat from being directly transferred to.

A temperature sensitive ferrite 2 as a temperature detecting sensor is closely attached to a terminal of the heat receiving plate 30 on the temperature detecting portion 101 side. A shaft 5 having a permanent magnet 3 and a magnetic yoke 4 made of a magnetic material having a high magnetic permeability at one end is disposed at a position opposed to the temperature-sensitive ferrite 2. The shaft 5 is provided with a spring 6 that applies a biasing force in a direction of separating the shaft 5 from the temperature-sensitive ferrite 2, and further, a beam portion for transmitting the movement of the shaft 5 to an adjacent optical switch portion 102 is integrally formed. A plate 7 is provided.

When the temperature of the temperature-sensitive ferrite 2 is low and the value of its magnetic permeability is high, the shaft 5 is pushed in the direction of the temperature-sensitive ferrite 2 to bring the permanent magnet 3 and the magnetic yoke 4 into close contact with the temperature-sensitive ferrite 2. Then, the temperature sensitive ferrite 2
Since a magnetic closed circuit is formed through the generation of a strong magnetic attraction force, the shaft 5 having the permanent magnet 3 and the magnetic yoke 4 arranged at one end adheres to the temperature-sensitive ferrite 2 against the biasing force of the spring 6. The state is maintained.

On the other hand, when the temperature of the temperature detection target object 200 rises and its heat is transferred to the temperature sensitive ferrite 2 through the heat receiving plate 30, the temperature of the temperature sensitive ferrite 2 rises. When the temperature exceeds the Curie temperature of the temperature-sensitive ferrite 2, the value of the magnetic permeability of the temperature-sensitive ferrite 2 is greatly reduced, so that the magnetic attraction force of the magnetic closed circuit becomes small and the biasing force of the spring 6 becomes dominant. , The shaft 5 is pulled away from the temperature-sensitive ferrite 2.

The optical switch section 102 provided adjacent to the temperature detecting section 101 of the temperature transmitter 100 is provided with the total reflection type reflector 9 described in the section of the prior art in a U-shape. The light shielding plate 7 coupled to the shaft 5 of the temperature detecting portion 101 through the beam portion is disposed and housed in the concave portion at a position where the light shielding plate 7 can enter. As a result, the optical switch section
The transmission axis of light in 102 is parallel to the axis of the shaft 5. An optical fiber 20 for projecting light and an optical fiber 21 for receiving light are provided in a mounting hole for the optical fiber formed in the reflector 9.
Are connected and coupled to form an optical switch unit 102.

As a member of the casing 1 for accommodating the temperature detecting unit 101 and the optical switch unit 102 described above, a molded article of engineering plastics is used for an object to be applied in a place where a peripheral magnetic field does not exist. It can be applied, but for applications to which the presence of a peripheral magnetic field should be taken into consideration, a magnetic material such as an iron material should be used to reduce the penetration of the peripheral magnetic field into the temperature detection unit 101 and prevent malfunction. is necessary. In the embodiment shown in FIG. 1, the inner box 11 made of engineering plastics for mounting and housing components is
It uses a structure that can be stored in an outer case 10 made of iron. It should be noted that the storage case made of a magnetic material was created as a magnetic shielding case that stores only the temperature detection unit 101, and the temperature detection unit 101 is
The magnetic shield case containing the above may be housed in the housing as the temperature transmitter 100 made of an engineering plastics molded product or the like.

[Second Embodiment of Magnetic Type Temperature Detector]
Next, FIG. 3 is a cross-sectional configuration diagram of a second embodiment of the magnetic type temperature detecting device according to the present invention, and FIG. 4 shows the temperature as seen from the bottom surface of the temperature detecting device of FIG. This embodiment will be described with reference to an explanatory diagram of the detection unit. In FIGS. 3 and 4, the same reference numerals are used for the elements having the same functions as those in FIG. 10 used for explaining the conventional technique and FIGS. 1 and 2 used for explaining the first embodiment. Since it is attached, the description thereof will be omitted.

In the temperature detecting device illustrated in FIGS. 3 and 4, 55 is a frame body in which the spring 6 can be housed.
55a and a shaft 5 are coaxially coupled to each other, which is a framed shaft in the form shown in the perspective view of FIG.
A light shielding plate 7 is provided on the frame surface facing the shaft of 55, and the permanent magnet 3 and the magnetic yoke 4 are attached by a bonding method or the like. 11a
Is a spring stopper that, when the framed shaft 55 is attached and housed in the inner box 11, projects from the main body of the inner box 11 into the frame body 55a of the framed shaft 55 and supports one end of the spring 6.
When assembling the temperature detecting device, the spring 6 is inserted in a compressed state between the frame body wall on the shaft side of the framed shaft 55 and the spring stopper 11a, and the permanent magnet 3 and the magnetic yoke 4 are connected to the temperature sensitive ferrite. A biasing force is applied in the direction of pulling it away from 2.

Reference numeral 31 denotes a heat receiving plate that transfers the heat of the temperature detection target object 200 to the temperature detecting unit 101 and holds the temperature transmitter 100 itself. In this embodiment, the heat receiving plate 31 is used.
Based on the present invention, the hanging screw holes provided in the hole are continuously drilled toward the end of the heat receiving plate 31 in an ascending order of diameter with a plurality of holes having different diameters offset from each other, and the heat receiving plate has the maximum diameter. It is cut to the end of 31 to form a Y shape.

When the magnetic temperature detecting device having the above structure is attached to the temperature detecting object 200 such as a bus bar, the mounting screw holes provided in the heat receiving plate 31 are formed in a Y-shape in which a plurality of holes having different diameters are connected. Therefore, the temperature detection target object
It is possible to use the screws provided in the 200 and insert the Y-shaped mounting hole portion of the heat receiving plate 31 to the position where it abuts the screws without loosening the screws and removing the screws, and fix the screws. .

As in the case of the first embodiment, the temperature detecting device is prepared for operation by pushing the framed shaft 55 in the direction of the temperature-sensitive ferrite 2 while the temperature of the temperature-sensitive ferrite 2 is low, and the permanent magnet 3 and the magnetic yoke 4 are brought into close contact with the temperature sensitive ferrite 2, a magnetic closed circuit is formed through the temperature sensitive ferrite 2 and a strong magnetic attraction force is generated. Therefore, the permanent magnet is resisted against the biasing force of the spring 6. The frame-shaped shaft 55 having the magnetic yoke 3 and the magnetic yoke 4 at one end is kept in close contact with the temperature-sensitive ferrite 2.

When the temperature of the temperature detection target object 200 rises, the temperature of the temperature sensitive ferrite 2 rises accordingly, and when the temperature exceeds the Curie temperature of the temperature sensitive ferrite 2,
Since the value of the magnetic permeability of the temperature sensitive ferrite 2 is greatly reduced,
The magnetic attraction of the magnetic closed circuit becomes small, the biasing force of the spring 6 becomes dominant, and the framed shaft 55 is moved to the temperature-sensitive ferrite 2
Pull away from.

[First Embodiment of Electric Device Using Magnetic Temperature Detector] FIGS. 6 to 8 are views showing an embodiment of an electric device using a magnetic temperature detector according to the present invention. FIG. 6 is a partial cross-sectional view showing the initial state of mounting the temperature detecting device, FIG. 7 is a partial cross-sectional view showing the state of mounting the temperature detecting device, and FIG. 8 is a perspective view showing the entire electric device. is there.

A magnetic type temperature detecting device is provided above or below the terminal board 200, which is the temperature detection target object of the electric device 400.
A storage space 41 for storing 110 is formed. In the storage space 41, a spring 46 made of an elastic member and a pressing plate 43 pressed by the spring 46 against the terminal plate 200 are provided as holding means. This holding plate 43
In this, a bent portion 44 is formed on the entrance side of the storage space 41 and a protrusion 45 is formed in the middle portion.

A storage space 41 for such an electric device 400
Magnetic temperature detecting device according to the present invention at the entrance of the
The state where 110 is inserted is the state shown in FIG. A hole 34 is provided at an intermediate portion of the portion of the heat receiving plate 30 of the temperature detecting device 110 that comes into contact with the terminal plate 200. In the state of FIG. 6, the heat receiving plate 30 of the temperature detecting device 110 is inserted into the storage space 41 along the terminal plate 200 (direction of arrow A). Then, the heat receiving plate
30 hits the bent portion 44 of the pressing plate 43, pushes it up, and is inserted between the terminal plate 200 and the pressing plate 43.
The protrusion 45 of the pressing plate 43 is inserted into the hole 34, and the attachment of the temperature detecting device 110 to the electric device is completed.

As described above, the temperature detecting device 110 can be easily attached by simply inserting the temperature detecting device 110 into the storage space 41 provided around the terminal board 200 of the electric device 400, and as in the prior art, The restriction that it must be installed after electrical wiring work is eliminated, the work process of electrical wiring and optical fiber wiring becomes free, and electrical equipment with a built-in terminal temperature detection function becomes possible.

FIG. 8 shows the three-phase terminal board 200 in this way.
Electrical equipment 400 with temperature detector 110 attached to each
FIG. 6 is a perspective view showing a case where one of the phases detects a temperature abnormal state, and in this case,
Since temperature monitoring may be performed collectively, the optical circuit of the temperature detecting device 110 is connected in series. That is, the light is incident on the temperature detecting device 110 at one end by the optical fiber 60, the adjacent temperature detecting devices 110 are connected by the short optical fiber 61, and the light is detected by the optical fiber 60 from the temperature detecting device 110 at the other end. Are taking out. In this way, the required length of the optical fiber is shortened, and at the same time, only one electro-optical converter 70 is required.

Incidentally, FIG. 9 shows a state in which the magnetic type temperature detecting device 110 according to the present invention is attached to the bus bar 80 as in the prior art, and even if such an attaching method is adopted. Since the display is thin and the connecting portions of the display and the optical fiber are all on the thin side surface, it can be attached to a portion which is difficult to attach by the conventional technique.

[0043]

According to the present invention, the shaft of the temperature detecting portion and the light transmission axis of the optical switch portion are arranged parallel to the mounting surface of the temperature detection target object through the L-shaped heat receiving plate. Since they are arranged, all the components that require an axial arrangement space are arranged parallel to the mounting surface, and as a result, they are mounted in a narrow space where the dimension in the direction orthogonal to the mounting surface of the temperature detection device is suppressed to a low value. The first effect is that a possible magnetic temperature detection device can be realized.

By arranging the optical switch section on the side remote from the mounting surface of the temperature detection target object via the temperature detection section, the size of the column portion for holding the temperature transmitter of the heat receiving plate can be reduced. In a temperature detection device that is longer than the insertion length into the temperature transmitter, when the temperature detection device is attached to the temperature detection target object, a space is secured between the temperature transmitter housing and the temperature detection target object, and By preventing heat conduction, even when the temperature of the temperature detection target object rises due to an abnormality, the increased temperature is quickly transmitted to the temperature sensitive ferrite of the temperature detection part through the heat receiving plate, but other parts, especially Since there is no direct heat conduction path to the reflector of the optical switch, the temperature of the reflector is kept low, so the total reflection reflector has a low heat resistance temperature but a low cost transparent resin part. Effect that can be applied.

Further, in a temperature detecting device using a magnetic material such as iron in a housing for accommodating the temperature detecting portion and the optical switch portion, when a large current flows in the temperature detection target object and a magnetic field is generated in the surroundings. However, since the peripheral magnetic field is shielded by the housing made of magnetic material and does not enter the magnetic circuit formation area of the temperature detection unit, it is possible to obtain the effect of ensuring normal temperature detection operation even in the presence of the peripheral magnetic field. To be

Further, in the temperature detecting device having the framed shaft provided with the frame body capable of accommodating the spring inside, the temperature detecting device is provided in the chassis after mounting the framed shaft in the chassis. Since a compressed spring can be inserted and assembled in the space area formed by the spring stopper and the frame body of the framed shaft, the shaft that penetrates the spring is mounted on the housing and then the spring stopper is fitted on the shaft Compared with, the assembly is easier, and it is not necessary to prepare a spring stopper as a component.

Furthermore, the temperature detecting device provided with the mounting screw holes provided in the heat receiving plate so as to form a Y-shape by connecting a plurality of holes having different diameters to each other is attached to the temperature detection target object. Since it is possible to use screws with different screw diameters that are provided in advance on the object, a screw hole for mounting the temperature detection device is separately processed on the temperature detection target object, and an attachment for screw diameter matching is prepared. The effect that there is no need to do is obtained.

In the magnetic type temperature detecting device according to the present invention, the operation display and the mounting portion of the optical fiber are surfaces orthogonal to the mounting surface to the temperature detection target object, and the end of the shaft which is the operation display portion. The part has a penetrating surface so that it can be inserted into a narrow space. Therefore, a space for inserting the temperature detecting device is provided on the upper surface or the lower surface of the terminal portion of the electric device, and a structure in which the heat receiving plate of the temperature detecting device can be crimped and held to the terminal plate by a spring is used to electrically connect the temperature detecting device It is possible to attach the temperature detection device to the device with one touch, and it is possible to attach the temperature detection device at any time regardless of the presence or absence of electric wiring to the electric device.

Furthermore, in an electric device having a plurality of temperature detecting devices, by connecting in series the optical fibers of these temperature detecting devices, the wiring of the optical fibers can be shortened and the wiring work can be simplified. And at the same time 1
It is possible to collectively monitor several temperature detection devices by using one electric-optical converter, and it is possible to reduce the number of electric-optical converters.

[Brief description of drawings]

FIG. 1 is a sectional view showing a first embodiment of a magnetic temperature detecting device according to the present invention.

FIG. 2 is an explanatory view showing an optical switch section in the embodiment of FIG.

FIG. 3 is a sectional view showing a second embodiment of the magnetic temperature detecting device according to the present invention.

FIG. 4 is a bottom perspective view of the embodiment of FIG.

FIG. 5 is a perspective view of a framed shaft.

FIG. 6 is a partial cross-sectional view showing an initial state of mounting the temperature detecting device in the first embodiment of the electric device using the magnetic temperature detecting device according to the present invention.

FIG. 7 is a partial cross-sectional view showing a state in which the temperature detecting device is mounted in the first embodiment of the electric device using the magnetic type temperature detecting device according to the present invention.

FIG. 8 is a perspective view showing an entire first embodiment of an electric device using a magnetic temperature detecting device according to the present invention.

FIG. 9 is a perspective view showing an example of a mounted state of a magnetic temperature detecting device according to the present invention.

FIG. 10 is an exploded perspective view showing a magnetic type temperature detecting device according to a conventional technique.

FIG. 11 is a temperature characteristic conceptual diagram showing a temperature change of magnetic attraction force of temperature-sensitive ferrite.

FIG. 12 is a perspective view showing an example of a mounted state of a magnetic type temperature detecting device according to a conventional technique.

[Explanation of symbols] 1 case 10 outer box 11 inner box 11a Spring stopper 12 Top lid 13 Bottom lid 15 units 2 Temperature-sensitive ferrite 3 Permanent magnet 4 Magnetic yoke 5 Shaft 51 Upper end portion 52 Beam 55 Framed shaft 55a Frame 6 Spring 7 Light-shielding plate 9 Reflector 20 Optical fiber 21 for emitting light Optical fiber for receiving 30, 31, 32 Heat receiving plate 34 Hole 36 Mounting screw 41 Storage space 43 Holding plate 44 Bending part 45 Protrusion 46 Spring 60 Optical fiber 61 Short optical fiber 70 Electric-optical converter 80 Busbar 100 Temperature transmitter 101 Temperature detection unit 102 Optical switch unit 110 Magnetic temperature detection device 200 Temperature detection target object (terminal plate) 201 Terminal screw 400 Electrical equipment

Front page continuation (72) Inventor Bunji Mori 1-1 Tanabe Nitta, Kawasaki-ku, Kawasaki-shi, Kanagawa Fuji Electric Co., Ltd. (56) Reference JP-A-7-225160 (JP, A) JP-A-4-225 212028 (JP, A) JP-A-7-72019 (JP, A) JP-A-6-102099 (JP, A) Actual development Sho 51-123879 (JP, U) (58) Fields investigated (Int.Cl. ⁷ , DB name) G01K 7/36 G01K 11/12

Claims (8)

(57) [Claims] 1. A temperature-sensitive ferrite, a heat receiving plate for transmitting heat of an object to be detected to the temperature-sensitive ferrite, a permanent magnet for magnetically attracting the temperature-sensitive ferrite, and a temperature-closed ferrite and permanent magnet magnetically closed circuit. A magnetic yoke made of a magnetic material having a high magnetic permeability and fixed to the permanent magnet, a shaft to which the permanent magnet and the magnetic yoke are fixed, and a biasing force that separates the permanent magnet from the temperature-sensitive ferrite. A temperature detection unit consisting of a spring attached to the shaft, a light-shielding plate that is fixed to the shaft and works together, a light projecting optical fiber that guides the light emitted from the light source, and an output from the light projecting optical fiber. An optical fiber for receiving light that guides light to the light receiving element, and a light receiving optical fiber that is provided across the optical fiber for projecting light and the optical fiber for receiving light. Are arranged in parallel in the same direction, reflect light in a direction orthogonal to the incident direction, and the condensing point is at a common position in the middle of the optical path between the end faces of the projecting optical fiber and the receiving optical fiber and both end faces. In the total reflection type, the reflecting surface has two curved reflecting surfaces, and the transparent member is formed at the common position so as to have a U-shaped concave portion into which the light blocking plate interlocking with the shaft enters. Is a magnetic temperature detecting device for detecting a temperature by a change in magnetic characteristics at a Curie point of a temperature-sensitive ferrite, the heat receiving plate being substantially L-shaped. And has a mounting surface at one end thereof, and the mounting surface of the heat receiving plate is mounted on the mounting surface of the temperature detection target object, and the shaft fixed to the permanent magnet and the magnetic yoke of the temperature detection unit and the optical Switch riff Of the optical fiber for projecting light and the optical fiber for receiving light coupled with the reflector and the reflector are arranged so as to be parallel to the mounting surface of the temperature detection target object. Temperature detection device. 2. With respect to the mounting surface of the temperature detection target object, a switch case accommodating the optical switch portion is arranged via a temperature detection part case accommodating the temperature detection part, and the heat of the temperature detection target object is directly The magnetic temperature detecting device according to claim 1, wherein the temperature detecting device is configured not to be transmitted to the optical switch unit. 3. The housing for accommodating the temperature detecting section is made of a magnetic material having a magnetic permeability sufficient to block a magnetic field generated around the temperature detection target object. Item 2. A magnetic temperature detection device according to Item 2. 4. A shaft to which a permanent magnet and a magnetic yoke are fixed is a framed shaft having a frame body capable of housing a spring therein, and a housing element for mounting and housing the framed shaft is The framed shaft is provided with a spring stopper that projects toward the inside of the frame and fixes one end of the spring, and the spring compressed in the space formed by the frame wall on the shaft side of the framed shaft and the spring stopper is used. 4. The magnetic temperature sensor according to claim 1, wherein the permanent magnet and the magnetic yoke are inserted so that an urging force is applied in a direction of separating the permanent magnet and the magnetic yoke from the temperature-sensitive ferrite. apparatus. 5. A screw hole to be attached to a temperature detection target object, which is provided on the heat receiving plate, is drilled toward the end of the heat receiving plate by connecting a plurality of holes having different diameters in the ascending order of diameters and connecting them in ascending order of diameter. 5. The magnetic temperature detecting device according to claim 1, wherein the temperature detecting device is provided so as to form a Y shape by cutting open to the end of the heat receiving plate with the diameter of. 6. A storage space capable of storing the magnetic temperature detecting device according to claim 1, wherein a holding means for holding the temperature detecting device is provided in the storage space. Electrical equipment that uses a magnetic temperature detector. 7. The holding means comprises a pressing member for pressing the heat receiving plate of the magnetic temperature detecting device and an elastic member for pressing the pressing member toward the terminal plate. Electrical equipment that uses a magnetic temperature detector. 8. A plurality of terminal plates, wherein the light projecting optical fiber and the light receiving optical fiber of the magnetic type temperature detecting device attached to these terminals are connected in series. Alternatively, an electric device using the magnetic temperature detecting device according to claim 7.