JP5092873B2 - Surface temperature sensor - Google Patents

Description

  The present invention relates to a planar temperature detection sensor that performs temperature detection in a planar region.

  Currently, there are many scenes in daily life that require temperature detection in a planar area. As an example, there is an IH cooking system. In the IH cooking system, by using induction heating based on the principle of electromagnetic induction, Joule heat is generated on the bottom surface of a pan pot or the like placed on the stove for cooking.

  In the case of such a system, if a conductive foreign substance exists on the mounting surface, the foreign substance generates heat and becomes locally hot.

  In order to detect such abnormal heat generation on a flat surface, for example, Patent Document 1 discloses a planar temperature detection sensor having a structure in which an electrode is formed on a sheet-like conductive polymer composition. FIG. 10 is a diagram showing a schematic configuration of a conventional planar temperature detection sensor, in which (A) shows a case where electrodes are formed on both opposing surfaces of a sheet-like conductive polymer composition, and (B) is a sheet. The case where the electrode is formed in one side of a conductive polymer composition is shown. The planar temperature detection sensor in FIG. 10A has a structure in which electrodes 901 and 902 are patterned on both opposing surfaces of a layered sheet 910. The detection unit 912 includes a layered sheet 910 and electrodes 901 and 902 facing each other with the layered sheet 910 interposed therebetween. On the other hand, the planar temperature detection sensor in FIG. 10B has a structure in which electrodes 901 'and 902' are formed on one surface of a layered sheet 910 at a predetermined interval. The detection unit 912 ′ includes a layered sheet 910 and electrodes 901 ′ and 902 ′ that are adjacent to each other without being directly connected by an electric circuit.

In the sensor having these structures, when the heating element comes into contact with the surface of the sheet-like conductive polymer composition, this heat is transferred to the layered sheet 910, and the resistance value of the layered sheet 910 is changed by the heat. Then, temperature detection is performed by detecting a voltage change between the electrodes 901 and 902 and between the electrodes 901 ′ and 902 ′ due to the change in the resistance value.
JP 2002-528874 A

  However, in the planar temperature detection sensor of Patent Document 1, since the entire layered sheet is formed of the conductive polymer composition, there is almost no difference in thermal conductivity between the detection unit and the non-detection unit. For this reason, heat is conducted almost equally to the detection part and the non-detection part, and almost all of the heat quantity of the heat generation source cannot be conducted to the detection part, and the accurate temperature of the heat generation part cannot be measured. Furthermore, in this configuration, the predetermined specific temperature detection timing is delayed from the timing at which the heat source actually reaches the specific temperature.

  Accordingly, an object of the present invention is to realize a planar temperature detection sensor with improved temperature detection accuracy and temperature detection speed.

  This invention is arranged in a predetermined pattern when viewed from the side of the detection surface inside the flat plate-shaped housing having one surface as a detection surface, each of which detects the temperature according to the temperature dependence of the electrical characteristics It is related with the planar temperature detection sensor provided with the some detection part which can perform. The plurality of detection portions of the planar temperature detection sensor are constituted by chip-type thermistor elements that are individually formed. Furthermore, the non-detection part which is an area | region between several detection parts consists of thermal conductivity lower than the thermal conductivity of a thermistor element.

  In this configuration, when the heating element comes into contact with the detection surface, the heat from the heating element is hardly conducted to the non-detecting portion having a relatively low thermal conductivity, and is conducted only to the thermistor element having a high thermal conductivity. Thereby, the heat from the heating element is applied to the thermistor element almost as it is, and the resistance value of the thermistor element changes according to the amount of heat. That is, the resistance value of the thermistor element changes accurately and quickly according to the temperature of the heating element.

  In the thermistor element of the planar temperature detection sensor according to the present invention, electrodes connected to different potentials are formed on two opposing side surfaces of the semiconductor ceramic body, and the direction connecting the opposing electrodes is relative to the detection surface. Are arranged vertically.

  In this configuration, heat is conducted from the electrode on the detection surface side of the thermistor element to the thermistor element in order. For this reason, the amount of heat difference (temperature difference) in a plane perpendicular to the direction connecting the opposing electrodes is smaller than when heat is applied from a surface other than the electrode surface of the thermistor element. As a result, the thermistor element can obtain a large rate of resistance change in a short period of time, so that highly accurate temperature detection is possible.

  The thermistor element of the planar temperature detection sensor of the present invention is a PTC type.

  This configuration utilizes the fact that the resistance value of the PTC thermistor element changes rapidly from a predetermined threshold temperature as the temperature rises. In such a PTC-type thermistor element, the smaller the amount of heat in the plane perpendicular to the direction connecting the opposing electrodes, that is, the temperature difference, the faster the resistance change rate is obtained as the thermistor element. Therefore, by using the PTC thermistor element and arranging the PTC thermistor element so that the direction connecting the opposing electrodes is perpendicular to the detection surface, temperature detection with higher accuracy is possible.

  In the thermistor element of the planar temperature detection sensor according to the present invention, electrodes connected to different potentials are formed on two opposing side surfaces of the semiconductor ceramic body, and the direction connecting the opposing electrodes is relative to the detection surface. Are arranged in parallel. Further, the connection electrode connected to the thermistor element is formed only on either the detection surface side or the non-detection surface side facing the detection surface.

  In this configuration, the connection electrodes for connecting a plurality of thermistor elements are formed on one plane, and the two electrodes facing the thermistor elements are mounted on the connection electrodes on the plane. The temperature detection sensor can be easily manufactured, and the height can be reduced.

  The casing of the planar temperature detection sensor according to the present invention has a structure including a detection side substrate on the detection surface side and a non-detection side substrate on the non-detection surface. The connection electrode is formed on the non-detection side substrate. Further, the thermistor element is covered with a covering resin member having a thermal conductivity substantially the same as that of the thermistor element and having an elastic coefficient that always makes the thermistor element and the detection side substrate contact each other.

  In this configuration, since the detection side substrate and the thermistor element are always in contact with each other by the covering resin member, the heat of the heating element is reliably conducted to the thermistor element through the detection side substrate and the covering resin member.

  According to the present invention, the change in the resistance value of the thermistor element accurately and quickly corresponds to the temperature of the heating element, so that the temperature of the heating element existing on the detection surface can be detected with high accuracy and speed.

A planar temperature detection sensor according to a first embodiment of the present invention will be described with reference to the drawings.
FIG. 1A is a plan view seen from the detection surface 111 side in a state where the detection side substrate 11 of the planar temperature detection sensor 10 of the present embodiment is removed, and FIG. 1B is a plan view of the planar temperature detection sensor 10. It is side surface sectional drawing which shows the part corresponded in the AA 'cross section of (A) in FIG. In FIG. 1, the thermistor element TH is shown in a side view in consideration of the visibility of the figure, and a number is representatively given to each element that exists in large numbers.

  The planar temperature detection sensor 10 has a casing made of a flat rectangular parallelepiped composed of a detection side substrate 11, a non-detection side substrate 12, and a side wall 13. The detection side substrate 11 is formed of a resin substrate having a thermal conductivity substantially equal to that of the thermistor element TH. One of the opposing flat plate surfaces (the upper surface in FIG. 1B) of the detection-side substrate 11 becomes the detection surface 111 and faces the outside of the housing. The non-detection side substrate 12 is formed of a resin substrate having a thermal conductivity lower than that of the thermistor element TH. The side wall 13 is formed along the periphery of the detection side substrate 11 and the non-detection side substrate 12 so that the detection side substrate 11 and the non-detection side substrate 12 are arranged in parallel. The side wall 13 is also formed of a resin having a thermal conductivity lower than that of the thermistor element TH, similarly to the non-detection side substrate 12. With such a structure, a closed space in the housing surrounded by the detection side substrate 11, the non-detection side substrate 12, and the side wall 13 is formed.

A plurality of thermistor elements TH are arranged in the closed space in the casing so as to be separated from each other in a predetermined arrangement pattern when viewed from the detection surface 111 side. These thermistor elements TH are so-called chip thermistors having a rectangular parallelepiped shape, and external electrodes are formed on two opposing wall surfaces among the six wall surfaces forming the rectangular parallelepiped. As the thermistor element TH, a BaTiO ₃ type PTC thermistor having a relatively high thermal conductivity is used. The thermistor element TH is arranged such that the direction connecting two wall surfaces (hereinafter referred to as external electrode surfaces) including external electrodes is perpendicular to the detection surface 111.

As a specific arrangement pattern of the thermistor elements TH, in the example of FIG. 1, 63 thermistor elements TH each have nine along two orthogonal directions (horizontal direction and vertical direction in the figure) along the side wall 13. Are arranged in a two-dimensional array. Here, the arrangement interval of the thermistor elements TH is set based on the following equation. That is, the arrangement interval is D, the width when the thermistor element TH arranged as described above is viewed from the detection surface 111 side is W, and the length of the thermistor element TH in the direction perpendicular to the detection surface 111 is L. In case,
L × 2 ≧ (D + W × 2) − (Formula 1)
The arrangement interval D is set so as to satisfy the above. For example, when the thermistor elements TH are 1.6 mm (L) × 0.8 mm (W1) × 0.8 mm (W2), the thermistor elements TH are arranged at intervals of 0.8 mm.

  As a specific example of the relationship of thermal conductivity, when the thermal conductivity of the thermistor element TH and the detection-side substrate 11 is 2.0 W / (m · K), the non-detection-side substrate 12 and the side wall 13 are used. Is set to 1.0 W / (m · K). For reference, the thermal conductivity of air is 0.02 W / (m · K).

  On the other hand, in the electrical structure, the pattern electrode 14 is formed on the housing inner side surface 112 of the detection side substrate 11, and the pattern electrode 15 is formed on the housing inner side surface 122 of the non-detection side substrate 12. These pattern electrodes 14 and 15 are made of a conductor having a low electrical resistance value and high thermal conductivity.

  Each thermistor element TH has one external electrode electrically and mechanically connected to the pattern electrode 14, and the other external electrode electrically and mechanically connected to the pattern electrode 15. With such a structure, the plurality of thermistor elements TH are electrically connected in series by the pattern electrodes 14 and 15. Specifically, in the example of FIG. 1, nine thermistor elements TH arranged in the horizontal direction shown in FIG. 1A are electrically connected in series by the pattern electrodes 14 and 15. External connection electrodes 16 </ b> A and 16 </ b> B that are exposed to the outside from the non-detection side substrate 12 through the side wall 13 are formed at both ends of these series circuits. Such series circuits are arranged in seven rows in parallel with the vertical direction shown in FIG. These series circuits are connected in series and then connected to the reference resistor and then connected to the power supply, or connected to the reference resistor and then connected to the power supply. Then, the change in the resistance value of the thermistor element TH is detected by measuring the output voltage of the series circuit, and the temperature is detected based on the change in the resistance value.

  With such a structure, the planar temperature detection sensor 10 has a plurality of thermistor elements TH arranged at a predetermined interval in the casing as a temperature detection unit, and the plurality of thermistor elements TH are not spaced apart. The structure exists as the detection unit 100.

Next, the temperature detection concept of the planar temperature detection sensor 10 having the above configuration will be described.
FIG. 2 is a conceptual diagram showing the heat conduction state of the planar temperature detection sensor 10 of the present embodiment, where (A) shows the case of the structure of the present embodiment and (B) shows the case of the structure of the prior art. Show.
As shown in FIG. 2A, in the case of the structure of the present embodiment, when the heating element 50 contacts the middle of the two thermistor elements TH on the detection surface 111, the heat from the heating element 50 is detected by the detection surface 111. Is conducted in the detection side substrate 11 and is conducted radially in the detection side substrate 11. When the heat conducted through the detection-side substrate 11 reaches the housing inner surface 112 of the detection-side substrate 11, the thermistor element having a higher thermal conductivity than the non-detection unit 100 whose substantial medium is air having a low thermal conductivity. Conduct to TH. Thereby, almost all the heat conducted from the heating element 50 to the planar temperature detection sensor 1 is given to the thermistor element TH. At this time, heat is conducted through the detection-side substrate 11 and is guided to the external electrode of the thermistor element TH, and is conducted from the external electrode into the thermistor element TH. As a result, heat conduction in the length direction of the thermistor element TH (perpendicular to the detection surface 111) and efficient heat conduction also on a plane parallel to the external electrode surface (detection surface 111). Due to this heat conduction, the thermistor element TH is heated with a small temperature difference on a plane parallel to the external electrode surface.

  On the other hand, as shown in FIG. 2B, in the case of the structure of the prior art, when the heating element 50 comes in contact with the middle of the two detection units 912 on the layered sheet 910, the heat from the heating element 50 is Conducts radially inside the 910. At this time, since the entire layered sheet 910 has the same thermal conductivity, heat is conducted in order from the non-detection part 913 between the detection parts 912. For this reason, the time until heat is conducted to the detection unit 912 is slower than in the case of (A) described above. Further, since the detection unit 912 and the non-detection unit 913 are integrated, heat is gradually generated from the surface side perpendicular to the detection surface of the detection unit 912 (the side wall side if replaced with the thermistor element TH) via the non-detection unit 913. Conduct. Due to such conduction, heating is performed in a state where a temperature difference on a plane parallel to the detection surface is large.

Incidentally, the resistance value of the PTC thermistor element TH varies depending on the temperature difference in the element as shown in FIG.
FIG. 3 is a diagram conceptually showing changes in the temperature distribution and resistance value in the element depending on the heating direction of the PTC-type thermistor element PTCTH. (A) shows the case of heating from the external electrode side, and (B) shows the element. The case where it heats from a side wall surface is shown.

  As shown in FIG. 3, by heating from the external electrode side, the PTC-type thermistor element PTCTH is heated evenly with respect to a plane parallel to the external electrode surface via the external electrode. On the other hand, when heating from the side wall surface of the housing, the heating on a plane parallel to the external electrode varies. For this reason, the temperature variation on the plane parallel to the external electrode is smaller in the case of heating from the external electrode side than in the case of heating from the side wall surface. Here, the PTC-type thermistor element PTCTH can be considered as equivalent to a plurality of individual PTC-type thermistors THe arranged in parallel along the direction connecting the opposing external electrodes. For this reason, as shown in (A), the resistance value of the plurality of individual PTC thermistors THe arranged in parallel is made uniform by heating in a state where there is little temperature variation on a plane parallel to the external electrode surface. It becomes higher (R (La)). For this reason, the overall resistance value of the PTC thermistor element PTCTH corresponding to the combined resistance in which these are connected in parallel also increases. On the other hand, as shown in (B), the resistance value of the plurality of individual PTC thermistors THe arranged in parallel is high by heating with a large temperature variation on a plane parallel to the external electrode surface. (R (La)) and low (R (sm)) exist. For this reason, the overall resistance value of the PTC thermistor element PTCTH corresponding to the combined resistance in which these are connected in parallel is unlikely to increase.

  As described above, the PTC thermistor element PTCTH can detect the temperature with higher accuracy as it is heated in a state in which the temperature variation on the plane parallel to the external electrode surface (detection surface 111) is small. Therefore, by using the configuration of this embodiment, temperature detection can be performed with high accuracy using the PTC-type thermistor element TH.

  Further, heat is not conducted to the non-detection unit 100 and heat conduction is concentrated only on the thermistor element TH corresponding to the detection unit, so that the heat conduction speed to the thermistor element TH is also increased. Thereby, the temperature detection speed can be increased by using the configuration of the present embodiment.

  FIG. 4A is a diagram illustrating the time-temperature characteristics of the thermistor element used in the present embodiment (first embodiment) and the monitor, and FIG. 4B is a resistance against time in the configuration of the present embodiment. The rate of change of resistance with respect to time in the configuration of the rate of change and the prior art (monitor) is shown. In this experiment, as shown in FIG. 2, the heating element 50 is installed between the thermistor elements TH or between the detection units 912, and the configuration of the present embodiment (first embodiment) is a PTC type thermistor that is a detection unit. The thermal conductivity of the element TH was 2.0 W / (m · K), the detected part 100 was a gap, and the thermal conductivity was 0.02 W / (m · K). Employing the above-described thermal conductivity relationship, with respect to the prior art, the detection unit 912 and the non-detection unit 913 are integrated PTC thermistor substrates, and the thermal conductivity is 2.0 W / (m · K). It is.

  The PTC thermistor according to the present invention has such a characteristic that it exhibits a resistance value that is 10 times the resistance value at room temperature (25 ° C.) at 65 ° C., as shown in FIG. The one that reached 65 ° C. in 32 seconds was used.

  FIG. 4B is a graph in which the vertical axis represents the resistance change rate which is the resistance value after the temperature rise with respect to the room temperature resistance value, and the horizontal axis represents time. As can be seen from this graph, it takes about 36 seconds for the resistance change rate of the first embodiment to be 10 times, but in the case of the monitor (prior art), it takes about 47 seconds. In other words, the rate of change in resistance is 10 times in the case of the configuration of the first embodiment at the same time of about 36 seconds, whereas in the case of the monitor (conventional technology), it is about 4 times. is there.

  Thus, it can be seen that by using the configuration of the present embodiment, a planar temperature detection sensor that detects temperature at high speed and with high accuracy can be realized.

  The number of thermistor elements TH and the arrangement pattern of the thermistor elements TH described above are merely examples, and may be set as appropriate according to the specifications. At this time, it may be arranged so as to satisfy the above (Formula 1), and the arrangement of (Formula 1) is preferable.

  Further, the relationship between the thermal conductivity of each element constituting the surface temperature detection sensor 10 may be set as appropriate according to the specification, but at least the thermal conductivity of the non-detection unit 100 is the thermal conductivity of the thermistor TH which is the detection unit. It should be less than half of the rate. By providing such a difference in thermal conductivity, heat conduction to the thermistor element TH can be effectively performed.

Next, a planar temperature detection sensor according to the second embodiment will be described.
FIG. 5A is a plan view seen from the detection surface side of the planar temperature detection sensor 20 of the present embodiment with the detection side substrate 21 removed, and FIG. 5B is a planar temperature detection sensor 20. It is side surface sectional drawing which shows the part corresponded in the AA 'cross section of (A) in FIG. In FIG. 5, the thermistor element TH is shown in a side view in consideration of the visibility of the figure, and a number is representatively given to each element that exists in large numbers.

In the planar temperature detection sensor 20 shown in FIG. 5 of the present embodiment, the non-detection part 100 of the planar temperature detection sensor 10 shown in FIG. Further, the non-detecting side substrate and the non-detecting part 200 are formed of the same resin. The other configurations are the same as those of the planar temperature detection sensor 10 shown in the first embodiment. That is, the planar temperature detection sensor 20 has a configuration in which the thermistor elements TH, which are detection units, are two-dimensionally arranged in a flat housing as viewed from the detection surface 211 side. The non-detecting portion 200 between the thermistor elements TH is filled with a resin having a lower thermal conductivity than the thermistor element TH. For example, if the thermistor element TH has a thermal conductivity of 2.0 W / (m · K) as in the first embodiment, it is set to 1.0 W / (m · K), which is the same as the non-detection side substrate 12. doing.
Even with such a structure, it is possible to effectively conduct heat to the thermistor element TH and improve temperature detection accuracy and temperature detection speed, as in the first embodiment.

Next, a planar temperature detection sensor according to the third embodiment will be described.
6A is a plan view seen from the detection surface side in a state where the detection side substrate 31 of the planar temperature detection sensor 30 of the present embodiment is removed, and FIG. 6B is a plan view of the planar temperature detection sensor 30. FIG. It is side surface sectional drawing which shows the part corresponded to the AA 'cross section of (A). In FIG. 6, the thermistor element TH is shown in a side view in consideration of the visibility of the figure, and a number is representatively given to each element that exists in large numbers.

  The planar temperature detection sensor 30 shown in FIG. 6 of the present embodiment is different from the first and second embodiments described above in that the thermistor element TH has an external electrode surface perpendicular to the detection surface 311. TH is arranged.

  The planar temperature detection sensor 30 has a plate-shaped casing including a detection side substrate 31, a non-detection side substrate 32, and an intermediate portion 33.

  The detection side substrate 31 is formed of a resin substrate having a thermal conductivity substantially equal to that of the thermistor element TH. One of the opposing flat plate surfaces (the upper surface in FIG. 6B) of the detection-side substrate 31 becomes the detection surface 311 and faces the outside of the housing. The non-detection side substrate 32 is formed of a resin substrate having a thermal conductivity lower than that of the thermistor element TH. For example, if the thermistor element TH has a thermal conductivity of 2.0 W / (m · K) as in the first embodiment, it is set to 1.0 W / (m · K), which is the same as the non-detection side substrate 12. doing. An electrode pattern 35 is formed on the housing inner side surface 321 of the non-detection side substrate 32, and the thermistor elements TH are mounted at predetermined intervals so as to be electrically connected to the electrode pattern 35. At this time, the thermistor element TH is mounted such that the external electrode surface is perpendicular to the housing inner side surface 321, that is, the side wall surface of the thermistor element TH is parallel to the housing inner side surface 321.

  The side surface of the thermistor element TH on the detection side substrate 31 side is in contact with the housing inner side surface 312 of the detection side substrate 31. In the region where the thermistor element TH is not mounted between the detection-side substrate 31 and the non-detection-side substrate 32 that sandwich the thermistor element TH, the thermal conductivity of the same material as the non-detection-side substrate 32 is thermistor. A resin lower than the element TH is filled.

  Even with such a configuration, it is possible to effectively conduct heat to the thermistor element TH and improve temperature detection accuracy and temperature detection speed.

  FIG. 7 is a diagram showing a resistance change rate with respect to time in the configurations of the first, second, and third embodiments and the configuration of the related art (monitor) used in FIG. 4B. Note that the PTC thermistors used for the configurations of the first, second, and third embodiments and the configuration of the monitor have the same time-temperature characteristics as those used in FIG. As can be seen from FIG. 7 which is the result of this experiment, the temperature detection accuracy and the temperature detection speed can be improved as compared with the prior art by using the configurations of the first, second and third embodiments described above. That is, the resistance change rate is 10 times in about 38 seconds in the second embodiment and about 41 seconds in the third embodiment. On the other hand, in the case of a monitor, the rate of change in resistance increases 10 times as described above for about 47 seconds, so the configuration of the first, second, and third embodiments of the present application has a higher detection speed. I understand that.

  In the description of the present embodiment, an example in which the electrode pattern 35 is formed on the non-detection-side substrate 32 has been described. However, an electrode pattern may be provided on the housing inner side surface 312 of the detection-side substrate 31.

Next, the planar temperature sensor 40 according to the fourth embodiment will be described.
FIG. 8A is a plan view seen from the detection surface 411 side in a state where the detection-side substrate 41 of the planar temperature detection sensor 40 of the present embodiment is removed, and FIG. 8B is a planar temperature detection sensor 40. It is side surface sectional drawing which shows the part corresponded in the AA 'cross section of (A) in FIG. In FIG. 8, the thermistor element TH is shown in a side view in consideration of the visibility of the figure, and a number is representatively given to each existing element.

  The planar temperature detection sensor 40 shown in FIG. 8 of the present embodiment is different from the planar temperature detection sensor 30 shown in FIG. 6 of the third embodiment in that the non-detection unit 300 in the housing is resin. The non-detection part 400 is a gap, and the thermistor element TH is molded with a resin 410. The resin 410 has the same thermal conductivity as the thermistor element TH. For example, if the thermistor element TH has a thermal conductivity of 2.0 W / (m · K) as in the first embodiment described above, the thermal conductivity of the resin 410 is also the same 2.0 W / (m · K). Set.

  With this configuration, since the non-detection unit 400 is a gap, the heat from the detection-side substrate 41 is conducted to the thermistor element TH via the resin 410 without being conducted to the non-detection unit 400. .

  Here, the resin 410 is in a form that can be applied and has a predetermined elastic force after further solidifying. Such a resin 410 is applied after the thermistor element TH is mounted on the electrode pattern 45 formed on the housing inner side surface 421 of the non-detection side substrate 42. And before the resin 410 hardens | cures, the detection side board | substrate 41 is installed in the application surface side of the resin 410 of the thermistor element TH. When the resin 410 is solidified, the detection-side substrate 41 and the thermistor element TH are joined by the resin 410. Here, by using a resin having a predetermined elastic force for the resin 410, the detection-side substrate 41 and the thermistor element TH are continuously bonded by the resin 410 even when an external force is applied from the detection surface side. Thereby, it can be manufactured by a relatively easy work process, and heat can be more reliably transmitted from the detection side substrate 41 to the thermistor element TH.

  As described above, the temperature detection accuracy and the temperature detection speed can also be improved by using the configuration of the present embodiment. Furthermore, by using the configuration of this embodiment, the planar temperature detection sensor can be manufactured by a relatively easy process.

In each of the above-described embodiments, the thermistor elements TH are connected to an external connection circuit after a predetermined number of serial connections are made, and the external connection circuit is exposed to the outside from the non-detection side substrate side.
However, an external connection electrode may be formed for each thermistor element TH and exposed to the outside. FIG. 9A is a side cross-sectional view of the planar temperature detection sensor 50 having an external connection electrode formed for each thermistor element TH. In the planar temperature detection sensor 50 shown in FIG. 9A, the thermistor elements are arranged so that the external electrode surfaces of the thermistor elements TH are perpendicular to the detection surface 511, as in the third embodiment. Yes. External connection electrodes 56A and 56B are formed for each thermistor element TH so that one end of the non-detection side substrate 52 of the housing is exposed from the non-detection surface 521 to the outside. Each external connection electrode 56A, 56B is connected to each external electrode of the corresponding thermistor element TH. With this configuration, the temperature detection result (resistance value change) for each thermistor element TH can be acquired individually.

  Further, the external connection circuit may be exposed to the outside from the side wall without being limited to the non-detection surface. FIG. 9B is a side cross-sectional view of the planar temperature detection sensor 60 in which the external connection circuit is exposed from the side wall to the outside. In the planar temperature detection sensor 60 shown in FIG. 9B, the thermistor elements are arranged so that the external electrode surfaces of the thermistor elements TH are perpendicular to the detection surface 611, as in the third embodiment. Yes. External connection electrodes 66A and 66B are formed on two opposing side wall surfaces of the casing. The external connection electrodes 66A and 66B serve as an input / output unit of a series circuit including a plurality of thermistor elements TH and pattern electrodes 64 and 65 that connect the plurality of thermistor elements TH in series. By using such a configuration, it is possible to output a signal in a direction parallel to the detection surface.

In each of the above-described embodiments, a PTC type thermistor element is shown as an example of the thermistor element, but an NTC type thermistor element may be used.
Further, in each of the above-described embodiments, the non-detection portion is a gap or is filled with a resin having low thermal conductivity. However, the non-detection portion has extremely low electrical conductivity and the thermal conductivity is a thermistor element. If the medium is less than half of the above, the above-described effects can be obtained.

It is a top view of the planar temperature detection sensor 10 of 1st Embodiment, (B) is side surface sectional drawing of the planar temperature detection sensor 10. FIG. It is a conceptual diagram which shows a concept about the heat conduction state of the planar temperature detection sensor 1 of 1st Embodiment. It is a figure which shows notionally the temperature distribution in an element by the heating direction of a PTC type thermistor element, and the change of resistance value. The figure which shows the time-temperature characteristic of the structure of 1st Embodiment, and the thermistor element used for the prior art (monitor), and the resistance change rate with respect to time in the structure of 1st Embodiment, and the structure of a prior art (monitor) FIG. It is a top view of the planar temperature detection sensor 20 of 2nd Embodiment, (B) is side surface sectional drawing of the planar temperature detection sensor 20. FIG. It is a top view of the planar temperature detection sensor 30 of 3rd Embodiment, (B) is side surface sectional drawing of the planar temperature detection sensor 30. FIG. It is a figure which shows the resistance change rate with respect to time in the structure of 1st, 2nd, 3rd embodiment and the structure of a prior art. It is a top view of the planar temperature detection sensor 40 of 4th Embodiment, (B) is side sectional drawing of the planar temperature detection sensor 40. 4 is a side cross-sectional view of the planar temperature detection sensor 50 and the planar temperature detection sensor 60. FIG. It is a figure which shows schematic structure of the conventional planar temperature detection sensor.

Explanation of symbols

10, 20, 30, 40, 50, 60-planar temperature detection sensor, 11, 21, 31, 41, 51, 61-detection side substrate, 12, 32, 42-non-detection side substrate, 13-side wall, 14 15, 35, 45, 55-pattern electrode, 16A, 16B, 26A, 26B, 36, 46, 56A, 56B, 66A, 66B-external connection electrode, 100, 200, 300, 400, 500, 600-non-detection , 111, 211, 311, 411, 511, 611-detection surface

Claims (5)

A flat housing with one surface as a detection surface;
A plurality of detection units arranged in a predetermined pattern when viewed from the detection surface side inside the housing, each capable of detecting temperature according to temperature dependence of electrical characteristics;
A surface temperature detection sensor comprising:
The plurality of detection units are chip-type thermistor elements each formed individually,
The non-detection part which is an area | region between these detection parts is a planar temperature detection sensor which consists of thermal conductivity lower than the thermal conductivity of the thermistor element.   In the thermistor element, electrodes connected to different potentials are formed on two opposing side surfaces of a semiconductor ceramic body, and the direction connecting the opposing electrodes is arranged to be perpendicular to the detection surface. The planar temperature detection sensor according to claim 1.   The planar temperature detection sensor according to claim 2, wherein the thermistor element is a PTC type. In the thermistor element, electrodes connected to different potentials are formed on two opposing side surfaces of a semiconductor ceramic body, and the direction connecting the opposing electrodes is arranged in parallel to the detection surface. And
The planar temperature detection sensor according to claim 1, wherein a connection electrode connected to the thermistor element is formed only on either the detection surface side or the non-detection surface side facing the detection surface. The housing includes a detection-side substrate on the detection surface side and a non-detection-side substrate on the non-detection surface,
The connection electrode is formed on the non-detection side substrate,
The thermistor element is covered with a covering resin member that has substantially the same thermal conductivity as that of the thermistor element and has an elastic coefficient that always brings the thermistor element and the detection-side substrate into contact with each other. 5. A planar temperature detection sensor according to 4.

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