JP4423564B2 - Temperature detection type magnetic device - Google Patents

Description

  The present invention relates to a magnetic component formed by winding a coil around a soft magnetic core. Here, the magnetic component includes both a reactor having one type of coil and a transformer having a plurality of types of coils. However, a reactor normally has a gap for preventing magnetic saturation in a magnetic path, but a transformer is required to minimize the gap.

  For example, in a power electronic circuit device such as a vehicle DCDC converter described in Patent Document 1 below, magnetic components such as a reactor and a transformer are widely used for applications such as current smoothing and input / output electrical insulation. A choke coil having a soft magnetic core is the same as a reactor. The DC-DC converter essentially requires high-speed switching, and superimposes a high-frequency switching noise voltage on the input voltage or output voltage. However, fluctuations in the voltage of the battery, which is a vehicle power supply, adversely affect its life. Therefore, in a DC / DC converter for a vehicle, a smoothing reactor that smoothes the input power or output power is an essential component. A DC / DC converter for a vehicle equipped with this type of reactor (including a choke coil with a core) is described in, for example, the following Patent Document 1 proposed by the present applicant.

  As a reactor used in a power range (several tens of watts to several tens of kW) applied to this type of vehicle power electronic circuit device, a dry reactor that is not immersed in oil is common. An example of this dry reactor is described in Patent Document 2 below, for example.

The most common type of this dry reactor is the columnar core having two pillars parallel to each other and two beams that magnetically connect the ends of these pillars. Coiled. As another modified form, there is also known a Japanese character core in which one column portion is further added in parallel with the two column portions of the square core and the central column portion is a common magnetic path. Since these square-shaped cores and date-shaped cores have a square core shape, they are also referred to as square cores hereinafter. In addition, a sealed core having a peripheral wall-shaped column portion around a central column portion around which a coil is wound is known. Since this core has a short cylindrical shape or a thick disc shape, it is also referred to as a disc-shaped core hereinafter. A magnetic part having a disk-shaped core has the advantage that the electromagnetic noise is reduced because the coil is surrounded by the peripheral wall-shaped column part, and the coil length can be shortened, compared with the magnetic part having a square core. Usually, there is a disadvantage that the idle space is large in the case of the power electronic circuit device having a rectangular shape.
JP 2000-014149 A JP 2004-241475 A

  Since these magnetic components used in power electronic circuit devices have large copper loss and iron loss, the temperature rise of the magnetic components usually requires cooling for magnetic components for power applications. However, even if cooling is performed, the temperature of the magnetic component may exceed the allowable limit due to an abnormality in the cooling mechanism or an increase in heat generation of the magnetic component. Of course, if the cooling capacity of the cooling mechanism is significantly increased, this problem can be alleviated, but the space occupied by the cooling mechanism in the power electronic component and the weight increase, thereby deviating from the limits allowed for the power electronic component. That is, in a normal vehicle power electronic circuit device, since the allowable vehicle power electronic circuit device is narrow, the improvement in cooling performance increases the space for the cooling mechanism and allows space for the magnetic component. The problem arises that the efficiency and output required for magnetic parts cannot be secured.

  The present invention has been made on the basis of the above problem recognition, and an object thereof is to provide a compact magnetic component by improving the output density to an allowable limit with high accuracy.

The magnetic component of the present invention made to solve the above problems includes at least two column portions parallel to each other, a magnetic coupling portion on one end side that magnetically connects one end portions of the column portions, and A soft magnetic core that forms a closed magnetic circuit having a magnetic coupling portion on the other end side that magnetically connects the other end portions, and a pair of coils wound individually on the two pillar portions And a temperature detection type comprising a magnetic component in which the outer peripheral surfaces of the pair of coils are close to each other with a predetermined gap therebetween, and a temperature sensor that is disposed on the magnetic component and detects the temperature of the magnetic component In the magnetic device, the temperature sensor is disposed between the two column portions and in the gap between the outer peripheral surfaces of the pair of coils. The core is preferably formed in a substantially square shape to form a so-called square core. The square core referred to in the present specification refers to a core having a substantially flat outer surface on which a column portion around which a coil is wound. Of course, the boundary between the two substantially flat outer surfaces of the square core may be chamfered and curved.

  In other words, according to the present invention, the temperature sensor for detecting the temperature of the magnetic component is embedded in the gap between the outer peripheral surfaces of the pair of coils respectively wound around the parallel pillar portions of the rectangular core. Since this gap is adjacent to the coil portion where the coil temperature of the magnetic sensor is highest, the maximum temperature can be detected well among the portions of the insulating coating coated on the coil conductor. Therefore, if the coil energization current is feedback-controlled so that the temperature detected by this temperature sensor does not exceed the predetermined maximum allowable temperature of the insulation film, the magnetic component cooling structure will be unnecessarily large or the coil current density will be excessive Therefore, the magnetic parts can be greatly downsized.

  In a preferred aspect, the temperature sensor is disposed at a substantially central sensor holding position in the magnetic path direction of the column portion in the gap between the outer peripheral surfaces of the pair of coils. In this way, the temperature sensor is arranged in the region where the temperature is highest in the gap between the outer peripheral surfaces of the pair of coils wound around the parallel pillars of the rectangular core. For this reason, the maximum temperature of each part of the insulating film coated on the coil conductor can be detected more satisfactorily. The substantially central sensor holding position referred to here refers to a region having a width of 10% of the length of each side from the center point of the outer surface of the two coils facing each other across the gap. .

  In a preferred aspect, a nonmagnetic sensor holding spacer that is inserted in a gap between the pair of coils in a magnetic path direction of the column portion and holds the temperature sensor at the sensor holding position. In this way, the temperature sensor can be accurately held at the sensor holding position. In particular, when the temperature sensor is held in the sensor holding spacer, when the core and coil of the reactor are molded with the mold resin, it is possible to prevent the temperature sensor from flowing and being displaced by the mold resin. Can do.

  In a preferred aspect, the sensor holding spacer has a groove for holding the temperature sensor. In this way, the temperature sensor can be firmly held at the sensor holding position by the sensor holding spacer having a simple shape. More specifically, in the temperature sensor, the displacement in all directions except for the opening direction of the groove is restricted by the sensor holding spacer in each surface direction of the sensor holding spacer, and the other pair of coils is used for the temperature sensor. The displacement in the direction can also be restricted.

  In a preferred aspect, the sensor holding spacer is made of a nonmagnetic and electrically insulating resin member. Preferably, the sensor holding spacer is preferably formed into a thin plate shape by an electrically insulating material. As a result, the sensor holding spacer can support the temperature sensor and also provide an electrical insulation effect between the pair of coils.

  In a preferred embodiment, the sensor holding spacer is made of a metal plate that is nonmagnetic and has good thermal conductivity. As a result, the sensor holding spacer can support the temperature sensor and dissipate the heat of the hottest portion of the coil to the outside. The surface of the metal plate may be electrically insulated, or an electrical insulating sheet may be interposed between the coil and the sensor holding spacer made of the metal plate.

  DESCRIPTION OF EXEMPLARY EMBODIMENTS Hereinafter, preferred embodiments of a reactor adopting the invention will be described with reference to the drawings. This reactor is used for current smoothing of a DCDC inverter for vehicles. However, the present invention should not be construed as being limited to the following embodiments, and it goes without saying that the technical idea of the present invention may be realized using other known techniques.

(First embodiment)
The whole structure of this reactor is shown in FIG.1 and FIG.2. The reactor 1 has a soft magnetic square core 2 and a coil 3 wound around the square core 2.

(core)
The U-shaped core 2 is formed by abutting two U-shaped cores 4 having the same shape. The U-shaped core 4 will be described with reference to FIGS. The U-shaped core 4 has two rectangular column portions 5 and one magnetic coupling portion 6 each formed by molding soft magnetic powder, and is formed in a U shape as a whole.

  The square column part 5 has two end faces (hereinafter also referred to as magnetic path end faces) through which magnetic flux enters and exits, and these two magnetic path end faces are arranged in parallel so as to face away from each other. The magnetic coupling portion 6 is a member that magnetically couples two rectangular column portions 5 that are arranged in parallel to each other, and has a small number of column portions that are continuous with the rectangular column portion 5. Bolt fastening holes 7 are formed in each corner of the magnetic coupling part 6 in the direction perpendicular to the magnetic path. The magnetic coupling part 6 has two magnetic path end faces on the same plane, and a magnetic path gap is formed between one magnetic path end face of the magnetic coupling part 6 and one magnetic path end face of one rectangular column part 5. A non-magnetic and electrically insulating spacer 8 is formed for forming the. In the U-shaped core 4 shown in FIGS. 3 and 4, the end surfaces of the magnetic paths on the side opposite to the spacer 8 of the two rectangular column parts 5 are exposed. The exposed magnetic path end faces of the two rectangular column parts 5 are also referred to as exposed magnetic path end faces 9. The B-shaped core 2 is configured by individually butting two exposed magnetic path end faces 9 of the two U-shaped cores 4 respectively. Note that a spacer similar to the spacer 8 is interposed between the two exposed magnetic path end faces 9 that are abutted with each other, as will be described later. The two rectangular column parts 5 which are abutted with each other are substantially accommodated in the coil 3 to form the column part referred to in the present invention. Therefore, the square-shaped core 2 is composed of two pillar portions and two magnetic coupling portions 6. Hereinafter, the two pillar portions may be referred to as a first pillar portion and a second pillar portion.

(coil)
The coil 3 is shown in FIG. The coil 3 is formed by connecting a first coil portion 10 wound around the first pillar portion of the lower core 2 and a second coil portion 11 wound around the second pillar portion of the lower core 2 in series. Become. Since the total four rectangular column parts 5 constituting the first column part and the second column part each have a prismatic shape, the first coil part 10 and the second coil part 11 each have a rectangular cylindrical coil shape. The first coil portion 10 and the second coil portion 11 are configured by bending a thick plate-like rectangular wire whose surface is coated with an insulating film in the width direction. The coil 3 is formed by winding a single flat wire, and the thickness direction of the flat wire is parallel to the magnetic path direction of the rectangular column portion 5.

  The coil 3 will be described in more detail with reference to FIG.

  Reference numerals 12 to 15 denote end portions (also referred to as terminal portions) of the first coil portion 10 and the second coil portion 11, and the insulating film at the tip portions is peeled off by a predetermined dimension. The first end portion 12 of the first coil portion 10 protrudes forward from the lower left side of the first coil portion 10, and the end portion 13 of the first coil portion 10 protrudes forward from the upper right side of the first coil portion 10. The end portion 14 of the second coil portion 11 protrudes forward from the upper left side of the second coil portion 11, and the start end portion 15 of the second coil portion 11 protrudes forward from the upper left side of the second coil portion 11. Further, the terminal end portion 13 of the first coil portion 10 and the start end portion 15 of the second coil portion 11 are overlapped and welded in the vertical direction in FIG. 5, that is, in the magnetic path direction (column portion magnetic path direction) of the rectangular column portion 5. ing.

(Half core)
The U-shaped core 4 and the spacer 8 described above are integrated by resin insert molding to constitute a U-shaped half core 16 shown in FIG. That is, the U-shaped half core 16 includes the U-shaped core 4 and the spacer 8 and the resin coating portion 17 that covers them. As shown in FIG. 6, the resin coating portion 17 has irregularities for engaging and fitting the two U-shaped half cores 16. In this embodiment, the exposed magnetic path end surfaces 9 of the two rectangular column parts 5 are exposed from the resin coating part 17, but may be covered by the resin coating part 17 to a substantially constant thickness. In this case, the portion of the resin coating portion 17 that covers the exposed magnetic path end face 9 constitutes a spacer.

  The resin coating portion 17 is located at the center in the left-right direction of the two rectangular column portions 5 (actually covered by the resin coating portion 17) arranged in parallel with each other, and extends in the front-rear direction. The support 18 is integrally provided. The sensor holding spacer 18 may be manufactured separately from the resin coating portion 17. The sensor holding spacer 18 is a resin plate and is nonmagnetic and electrically insulating. Eventually, the square core 2 of the reactor 1 has a total of six magnetic gaps. The sensor holding spacer 18 is chamfered at the front and upper corners to constitute a linear taper surface 19 for defining a groove for inserting a temperature sensor described later.

(Assembly of reactor 1)
The assembly of the two U-shaped half cores 16 and the coil 3 will be described with reference to FIG. A spacer 20 is disposed between the exposed magnetic path end faces 9 of the two U-shaped half cores 16. The spacer 20 is, for example, a plate material such as resin, glass, or ceramic, and is fixed to the core end surface with an adhesive. Reactor 1 formed in this way is housed in a metal case 21 made of an aluminum alloy having a front end opening as shown in FIG. 8. Mold resin 22 is sealed in metal case 21 to seal reactor 1. ing.

  As shown in FIG. 8, the metal case 21 has a stepped protrusion 23 a protruding rearward at the center in the vertical direction of the bottom surface 23 on the rear end side. The metal case 21 has case holes 24 (see FIG. 9) respectively communicating with the two bolt fastening holes 7 provided in either of the two U-shaped cores 4. In FIG. 24 is not visible.

(Vehicle DCDC converter)
Next, the operation of assembling the reactor 1 to the vehicle DCDC converter will be described below with reference to FIG. FIG. 9 is a diagram illustrating a main part of the DC-DC converter for a vehicle.

  25 is a liquid-cooled inverter device for a DC-DC converter for a vehicle, and this inverter device 25 has a semiconductor card module 26 in which main electrodes are exposed on a total of 12 surfaces each incorporating a semiconductor element. The card module 26 is alternately stacked with a total of 13 liquid cooling fins 27. In addition, an electrical insulating film or sheet is interposed between the semiconductor card module 26 and the liquid cooling fin 27 for electrical insulation during the lamination. Note that a total of 12 semiconductor card modules 26 constitute switching elements or flywheel diodes for each of the three-phase arms. The liquid cooling fins 27 are formed by overlapping two identical aluminum plates and brazing their outer peripheral edges, and a liquid flow path is formed in the vertical direction inside. In addition, among the liquid cooling fins 27, black thick lines extending vertically in FIG. 9 indicate outer peripheral edges of the brazed liquid cooling fins 27. The upper ends of the liquid cooling fins 27 are brazed so that the liquid flow paths are formed in the left-right direction, thereby forming a so-called inflow header. Similarly, the lower end portion of each liquid cooling fin 27 is brazed so that the liquid flow path is formed in the left-right direction, thereby forming a so-called outflow header. In FIG. 9, a cooling liquid inflow pipe 29 and a cooling liquid outflow pipe 30 are brazed to the rightmost liquid cooling fin 27. Of course, the coolant inflow pipe 29 communicates with the right end of the inflow header, and the coolant outflow pipe 30 communicates with the right end of the outflow header.

  Reference numeral 31 denotes an aluminum alloy converter housing (case referred to in the present invention) that houses a DCDC converter for a vehicle, and is die-cast in a square box shape with one end opening. The above-described liquid cooling type inverter device 25 is fixed to the converter casing 31 together with the liquid cooling device having the SPS structure described above.

  Adjacent to the right end of the liquid-cooled inverter device 25, the reactor 1 is fixed by a bolt (not shown) that passes through the bolt fastening hole 7 and the case hole 24 and is fastened to the converter housing 31. . Only the bolt fastening hole 7 of the magnetic connecting portion 6 on the upper end side of the reactor 1 is fastened, but the bolt fastening hole 7 of the magnetic connecting portion 6 on the lower end side of the reactor 1 is free. That is, the reactor 1 and the metal case 21 to be accommodated do not have the case hole 24 communicating with the bolt fastening hole 7 of the magnetic coupling portion 6 on the lower end side of the reactor 1, and as a result, the reactor 1 is connected to the converter housing 31. One end is supported in the column magnetic path direction (vertical direction in FIG. 9), and the magnetic coupling portion 6 on the lower end side of the reactor 1 is a free end with respect to the converter housing 31 in the metal case 21.

  A side wall 21 a on the left end side of the metal case 21 that houses the reactor 1 is disposed in close contact with the right main surface of the rightmost liquid cooling fin 27 that forms the right end surface of the liquid cooling inverter device 25. In addition, in order to improve the adhesiveness between the left end side wall 21a of the metal case 21 and the rightmost liquid cooling fin 27, heat conductive grease may be applied, or both may be joined by various methods. .

  Of the first coil portion 10 and the second coil portion 11 in the metal case 21, the outer peripheral surface of the first coil portion 10 is the rightmost side via the mold resin in the metal case 21 and the side wall 21 a of the metal case 21. The liquid cooling fins 27 are cooled. That is, among the liquid cooling fins 27 of the liquid cooling type inverter device 25, the outer main surface of the outermost liquid cooling fin 27 is not used for cooling the semiconductor module. The outer main surface of the cold fin 27 is used for heat transfer cooling of the reactor 1.

  In this embodiment, the outermost liquid cooling fin 27 faces the outer peripheral surface of the first coil portion 10 through the side wall of the metal case 21 and the mold resin. Thereby, the coil 3 that needs to be cooled in preference to the core is cooled well. The second coil part 11 is cooled well through the excellent thermal conductivity of the rectangular wire constituting the first coil part 10. Note that the arrangement of the reactor 1 may be changed so that both the outer peripheral surface of the first coil unit 10 and the outer peripheral surface of the second coil unit 11 are opposed to the outermost liquid cooling fin 27.

  Further, since the cooling liquid inflow pipe 29 and the cooling liquid outflow pipe 30 are interposed, the metal case 21 is accommodated in the metal case 21 by bringing the cooling liquid inflow pipe 29 and the cooling liquid outflow pipe 30 into contact with each other. The reactor 1 thus made can be cooled well from three sides.

(Modification)
In the above embodiment, the metal case 21 and the converter housing 31 are configured separately and fastened. However, as shown in FIG. 10, the metal case 21 that accommodates the reactor 1 and the converter housing 31 are integrally formed with a die. It may be cast to form an integral case. In this case, the side wall 21 a, which is one of the four rectangular side walls corresponding to the metal case 21 of the integral case, comes into contact with the outermost liquid cooling fin 27.

  The four side walls of the metal case 21 include a side wall 21 a that faces the outer peripheral surface of the first coil unit 10, a side wall that faces the outer peripheral surface of the second coil unit 11, and two side walls that face the magnetic coupling unit 6. . Here, when the side wall 21a of the metal case 21 facing the first coil portion 10 (or the outer peripheral surface of the second coil portion 11) is in close contact with the outermost liquid cooling fin 27 (when the coil is brought close to the cooler) a When the side wall of the metal case 21 facing the magnetic coupling portion 6 of the square core 2 is in close contact with the outermost liquid cooling fin 27 (when the core is brought close to the cooler) b, The center temperature of the reactor 1 was measured. The measurement results are shown in FIG. In FIG. 11, with the passage of time in a state where a constant current was passed through the coil, in the case of a, the temperature was slightly over 100 ° C., but in the case of b, the value was close to 120 ° C. .

  Next, the arrangement of the temperature sensor 32 used for the temperature detection will be described with reference to FIGS. The temperature sensor 32 has a built-in thermistor and is disposed at a central position X (see FIG. 2) in the column magnetic path direction of the coil 3 in an intermediate gap between the first coil unit 10 and the second coil unit 11. Yes. Moreover, it arrange | positions in the front-back direction center part (refer FIG. 8) which is the axial direction of the 1st coil part 10 and the 2nd coil part 11. As shown in FIG. That is, the temperature sensor 32 is arranged at the three-dimensional center position X of the reactor 1. This position is a portion where the temperature is highest in the reactor 1 due to heat generated by the first coil unit 10 and the second coil unit 11 on both sides, and the temperature sensor 32 detects the maximum temperature of the reactor 1. The measurement result of each part temperature of the reactor 1 is shown in FIG. It can be seen that the temperature at the central position X of the reactor 1 is considerably higher than the coil temperature (peripheral part) and the core temperature (peripheral part).

  The arrangement of the temperature sensor 32 will be described in more detail with reference to FIG.

  The sensor holding spacer 18 integrally formed with the resin coating portions 17 of the two U-shaped cores 4 faces the vertical direction and forms a groove portion 18A in which the temperature sensor 32 is accommodated. The groove 18A has an opening that is partitioned by the linear tapered surfaces 19 of the two sensor holding spacers 18 and gradually increases toward the front. The straight bar-shaped temperature sensor 32 is inserted from the opening of the groove 18A to the center position (see FIG. 2) X. After the temperature sensor 32 is inserted, a liquid or jelly-like mold resin is injected into the metal case 21 and solidified, whereby the reactor 1 and the temperature sensor 32 are fixed at predetermined positions. The sensor holding spacer 18 holds the temperature sensor 32 when the mold resin is injected to prevent displacement. In the case where the two sensor holding spacers 18 are formed separately from the resin coating portion 17, the two sensor holding spacers 18 can be replaced by one grooved resin plate.

(Second Embodiment)
In the above embodiment, the sensor holding spacer 18 is formed by two resin plates forming the temperature sensor clamping groove 18A, or one resin plate having the groove 18A, and this resin plate is the first coil. The sensor holding spacer 18 may be formed of a thin metal plate such as an aluminum alloy plate, although the sensor holding spacer 18 is interposed in the gap between the portion 10 and the second coil portion 11. In this case, the sensor holding spacer 18 made of a thin metal plate holds the temperature sensor 32 and also has a region between the first coil portion 10 and the second coil portion 11 that is the most severe in temperature. Heat can be dissipated well to the outside. When the sensor holding spacer 18 is used as a heat transfer plate in this way, the edge of the sensor holding spacer 18 is exposed from the gap between the first coil portion 10 and the second coil portion 11 to the outside. It is preferable to protrude and contact, for example, the metal case 21 or the like. Furthermore, when considering electric insulation, the surface of the sensor holding spacer 18 made of a thin metal plate may be covered with a resin sheet or film for electric insulation.

It is a perspective view of the reactor of Embodiment 1. It is a front view of the reactor of Embodiment 1. It is a front view which shows a U-shaped core. It is a disassembled perspective view of a U-shaped core. It is a perspective view of a coil. It is a perspective view of a U-shaped half core. It is a disassembled perspective view of the reactor of Embodiment 1. FIG. It is an AA arrow directional cross-sectional view of the reactor of Embodiment 1. It is a partial front view of the DCDC converter for vehicles by which the reactor was mounted. It is a disassembled perspective view of the DCDC converter for vehicles by which the reactor was mounted. It is a characteristic view which shows the difference in coil temperature at the time of making the core side surface and coil side surface of a reactor close to a liquid cooling fin. It is a characteristic view which shows the difference in the temperature of each part of a reactor.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Reactor 2 B-shaped core 3 Coil 4 U-shaped core 5 Square column part 6 Magnetic coupling part 7 Bolt fastening hole 8 Spacer 9 Exposed magnetic path end surface 10 Coil part 10a Left side 10b Front side 10c Right side 11 Coil part 11b Front side 11c Left side 12 Start end portion 12a End portion 13 End portion 13a End portion 14 End portion 14a End portion 15 Start end portion 16 U-shaped half core 17 Resin coating portion 18 Sensor holding spacer 18A Groove portion 19 Linear taper surface 20 Spacer 21 Metal case 21a Side wall 22 Mold resin 23 Bottom surface 23a Step protrusion 24 Case hole 25 Liquid cooling type inverter device 26 Semiconductor card module 27 Liquid cooling fin 29 Cooling liquid inflow pipe 30 Cooling liquid outflow pipe 31 Converter housing 32 Temperature sensor

Claims (6)

At least two pillar parts parallel to each other, one end side magnetic coupling part magnetically connecting one end part of the pillar part, and the other end side magnetic coupling magnetically connecting the other end parts of the pillar part And a pair of coils individually wound around the two pillars, and the outer peripheral surfaces of the pair of coils are a predetermined gap. Magnetic parts that are close to each other,
A temperature sensor disposed on the magnetic component for detecting the temperature of the magnetic component;
In a temperature detection type magnetic device comprising:
The temperature sensor is
The temperature detection type magnetic apparatus according to claim 1, wherein the temperature detection type magnetic apparatus is disposed between the two column portions and in the gap between the outer peripheral surfaces of the pair of coils. The temperature detection type magnetic device according to claim 1,
The temperature sensor is
A temperature detection type magnetic device, wherein the temperature detection type magnetic device is disposed at a sensor holding position at a substantially central position in the magnetic path direction of the column portion within the gap between the outer peripheral surfaces of the pair of coils. The temperature detection type magnetic device according to claim 1 or 2,
A temperature detection comprising a non-magnetic sensor holding spacer that is inserted in a gap between the pair of coils in the magnetic path direction of the column portion and holds the temperature sensor at the sensor holding position. Type magnetic device. In the temperature detection type magnetic device according to claim 3,
The temperature sensor type magnetic device, wherein the sensor holding spacer has a groove for holding the temperature sensor. In the temperature detection type magnetic device according to claim 3,
The temperature sensor type magnetic device, wherein the sensor holding spacer is made of a non-magnetic and electrically insulating resin member. In the temperature detection type magnetic device according to claim 3,
The temperature sensor type magnetic device, wherein the sensor holding spacer is made of a non-magnetic metal plate having good thermal conductivity.

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