JP5959111B2 - Heat flow sensor - Google Patents

Description

  The present invention relates to a heat flow sensor that predicts the temperature of an object to be measured by measuring the heat flow.

  2. Description of the Related Art Conventionally, a heat flow sensor that can predict the temperature of a deep part of a measurement object by measuring the heat flow is known. For example, the body temperature of a living body can be distinguished from a core part and a body surface part, and the core part is a tissue inside the living body, and the temperature is not affected by heat dissipation to the surrounding environment. On the other hand, the body surface is affected by heat exchange with the surrounding environment, and its temperature tends to be variable.

  When measuring the body temperature of a living body, it is important to measure and grasp the core temperature in order to confirm the medical condition and state of the subject, so a deep thermometer that measures the core temperature is important. Has been developed.

  On the other hand, an induction heating cooker has been proposed that uses a heat flow sensor that measures heat flux in order to predict the temperature of the pan instantaneously and accurately (see Patent Document 1). This heat flow sensor is arranged such that one side of the substrate is in contact with the heat receiving plate, and the substrate is erected in the vertical direction to the heat receiving plate.

JP 2009-156753 A

However, in the case of the heat flow sensor as described above, in order to measure the temperature of the measurement object, when the heat flow sensor is used in contact with the measurement object, there is a problem that the protrusion amount (protrusion height dimension) increases.
The present invention has been made in view of the above problems, and an object thereof is to provide a heat flow sensor that can reduce the amount of protrusion.

The heat flow sensor according to claim 1 is formed on a substrate, at least two temperature sensors disposed at a predetermined interval on one surface side of the substrate, and inclined at an end surface of the substrate, and the temperature. It is characterized by comprising a contact portion positioned facing one of the sensors, and a synthetic resin case in which the substrate is accommodated in an inclined manner.

The heat flow sensor according to claim 2 is a substrate, three or more temperature sensors arranged at a predetermined interval on one surface side of the substrate, and one of the temperature sensors on the other surface side of the substrate. And a contact portion positioned opposite to the contact portion.

The heat flow sensor according to claim 3 is the heat flow sensor according to claim 1 or 2 , wherein the thermal conductivity of the substrate is 0.1 W / m · K to 500 W / m · K. And
According to this invention, it becomes easy to obtain an optimal temperature difference or responsiveness in the temperature sensor.

The heat flow sensor according to claim 4 is the heat flow sensor according to any one of claims 1 to 3 , wherein the contact portion protrudes from an outer surface of the case by 0.1 mm to 1 mm. To do.
According to this invention, it becomes possible to make a contact part contact a measurement object reliably.

  ADVANTAGE OF THE INVENTION According to this invention, protrusion amount can be made small and the heat flow sensor which is easy to handle can be provided.

It is a perspective view showing a heat flow sensor concerning a 1st embodiment of the present invention. It is a perspective view which shows the heat flow sensor seeing from the heat sensitive surface side (back side). It is a perspective view which shows typically the board | substrate with which the thermal element in the same heat flow sensor was formed. It is a side view which shows the case in the heat flow sensor in cross section. It is a perspective view which shows the assembly process of the same heat flow sensor. Similarly, it is a perspective view which shows the assembly process of a heat flow sensor. Similarly, it is a perspective view which shows the assembly process of a heat flow sensor. Similarly, it is a perspective view which shows the assembly process of a heat flow sensor. Similarly, it is a perspective view which shows the assembly process of a heat flow sensor. It is a perspective view which shows the heat flow sensor which concerns on the 2nd Embodiment of this invention. It is a perspective view which shows the heat flow sensor seeing from the heat sensitive surface side (back side). It is a side view which shows the case in the heat flow sensor in cross section. It is a perspective view which shows the assembly process of the same heat flow sensor. Similarly, it is a perspective view which shows the assembly process of a heat flow sensor. Similarly, it is a perspective view which shows the assembly process of a heat flow sensor. Similarly, it is a perspective view which shows the assembly process of a heat flow sensor. Similarly, it is a perspective view which shows the assembly process of a heat flow sensor. Similarly, it is a perspective view which shows the assembly process of a heat flow sensor. It is explanatory drawing which shows the method of the temperature measurement in a heat flow sensor. It is a graph which shows the relationship between heat source temperature and the calculated value of a heat flow sensor. It is a side view which shows the case in the heat flow sensor which concerns on the 3rd Embodiment of this invention in cross section (Example 1). It is a side view which shows the case in the same heat flow sensor in cross section (Example 2).

The heat flow sensor according to the first embodiment of the present invention will be described below with reference to FIGS. FIG. 1 is a perspective view showing a heat flow sensor, FIG. 2 is a perspective view showing the heat flow sensor as seen from the heat sensitive surface side (back side), and FIG. 3 is a schematic view of a substrate on which a heat sensitive element is formed. It is a perspective view shown in FIG. FIG. 4 is a side view showing a cross section of the case in the heat flow sensor, and FIGS. 5 to 9 are perspective views showing the assembly process together with the structure of the heat flow sensor. In addition, in each figure, in order to make each member into a recognizable size, the scale of each member is appropriately changed.
The heat flow sensor in this embodiment is a deep thermometer for measuring the temperature of the core of a living body.

  As shown in FIGS. 1 to 4, the heat flow sensor 1 includes a substrate 2, a first thermal element 21 and a second thermal element 22 as temperature sensors formed on the substrate 2, a contact portion 3, And a case 4 that is flat and accommodates the substrate 2 and has a substantially rectangular parallelepiped shape.

  As representatively shown in FIG. 3, the substrate 2 is made of an alumina material and has a substantially rectangular shape. The length is about 4 mm to 6 mm, the width is about 1 mm to 2 mm, and the thickness is about 0. .1 mm to 0.4 mm. On the substrate 2, a wiring pattern 24 made of platinum, a terminal portion 25 for electrically connecting the thermal elements 21 and 22, and a terminal portion 26 for connecting the lead wires 9 are formed by sputtering or the like.

  The first thermosensitive element 21 and the second thermosensitive element 22 are made of a thin film thermistor, and the thin film thermistor is a complex oxide made of manganese (Mn), cobalt (Co), nickel (Ni), iron (Fe), or the like. The film is formed by sputtering using the sintered body as a target.

  Specifically, the first thermosensitive element 21 and the second thermosensitive element 22 are arranged at two locations at a predetermined interval along the longitudinal direction on one surface side (front surface side) of the substrate 2. Therefore, the temperature is detected at two locations. The first heat sensitive element 21 and the second heat sensitive element 22 are each covered with a protective film 27. The protective film 27 is formed by applying a glass paste by screen printing and sintering.

  The material of the substrate 2 is not limited to alumina, and zirconia, sapphire, quartz, silicone, polyimide, glass epoxy, or the like can be applied. Furthermore, a metal substrate in which an insulating layer is formed on a metal plate can be used. In this case, the thermal conductivity of the substrate 2 is preferably in the range of 0.1 W / m · K to 500 W / m · K. Within this range, an optimum temperature difference or responsiveness can be easily obtained.

  The first thermal element 21 and the second thermal element 22 are not limited to thin film thermistors, and surface mount type chip thermistors can be used. In addition, the shape, dimensions, and materials of the heat flow sensor 1 are not limited to specific ones.

  As shown in FIGS. 2 and 4, the contact portion 3 is a substantially quadrangular member made of a material having good thermal conductivity. This contact portion 3 is made of, for example, stainless steel, and faces one of the first thermal element 21 and the second thermal element 22 on the other surface side (back surface side) of the substrate 2. positioned. Specifically, it faces the first thermosensitive element 21 and is located on the other surface side of the substrate 2. The contact portion 3 is not limited to stainless steel, and other metal materials can be applied as long as the material has good thermal conductivity. The contact portion 3 is required to have good thermal conductivity, and the thermal conductivity is preferably in the range of 1 W / m · K to 500 W / m · K. Note that the contact portion 3 does not prevent the contact portion 3 from being formed integrally with the substrate 2, and may be formed integrally with the substrate 2 or a separate member.

  When the contact portion 3 is formed integrally with the substrate 2, for example, the substrate 2 can be formed by partially protruding from the other surface side of the substrate 2. In this case, the contact portion 3 and the substrate 2 are made of the same material and have the same thermal conductivity.

In the present embodiment, the contact portion 3 has a case 4 in which a thermally conductive member 5 that improves the adhesion between the substrate 2 and the contact portion 3 is interposed between the other surface side of the substrate 2 and the contact portion 3. Installed on. For example, a graphite sheet having predetermined flexibility and thermal conductivity is used for the thermal conductive member 5. The thermal conductive member 5 is not limited to a graphite sheet as long as it can improve the adhesion between the substrate 2 and the contact portion 3 and has thermal conductivity, and synthetic resin, ceramics, metal material, or the like can be used. Further, grease, adhesive, or solder having good thermal conductivity may be used as the thermal conductive member 5.
As shown in FIG. 4, the case 4 is made of a synthetic resin material such as ABS resin, and includes a base portion 6 and a lid portion 7.

  As shown with reference to FIGS. 5 to 9, the case 4 is formed in a substantially rectangular parallelepiped shape, and includes a base portion (lower member) 6 and a lid portion (upper portion) that covers the opening of the base portion 6. Member) 7.

  The base portion 6 includes a substantially rectangular bottom wall 61, an inner peripheral wall 62 standing slightly inward from the outer peripheral edge of the bottom wall 61, and a substantially central portion of the inner peripheral wall 62 in the longitudinal direction. A pair of substrate positioning walls 63 formed along the side and a lead wire holding wall 64 formed on the rear side and having a lead wire holding groove. Further, as mainly shown in FIG. 4, a fitting portion 65 to which the contact portion 3 is fitted and attached is formed on the front back side of the bottom wall 61 so as to have a rectangular concave shape. A part of the fitting portion 65 penetrates the bottom wall 61 so that an opening 66 is formed.

  Further, as representatively shown in FIG. 4, a recess 67 that is slightly recessed toward the back side is formed between the pair of substrate positioning walls 63 in the bottom wall 61. The recess 67 forms a heat insulating layer Is-1 as will be described later.

  As shown in FIGS. 4 and 9, the lid portion 7 has a substantially rectangular cover wall 71, an outer peripheral wall 72 erected from the outer peripheral edge of the cover wall 71, and an inner position of the outer peripheral wall 72. A projecting wall 73 projecting in the same direction as the outer peripheral wall 72 and a lead wire holding wall 74 formed on the rear side are provided.

As shown in FIG. 4, in a state where the base portion 6 and the lid portion 7 are combined, a heat insulating member 8 having elasticity is provided between the protruding wall 73 in the lid portion 7 and the surface side of the substrate 2. The substrate 2 is pressed toward the bottom wall 61 side of the base portion 6. The heat insulating member 8 is formed in a substantially rectangular parallelepiped shape, and for example, a material such as silicone rubber or urethane rubber is used.
Next, the detailed configuration of the heat flow sensor 1 will be described together with the assembly process of the heat flow sensor 1 with reference to FIGS.

  First, as shown in FIG. 5, the contact portion 3 is fitted and attached to the fitting portion 65 of the base portion 6. In this case, although the contact part 3 is supported by the fitting part 65, you may make it adhere | attach the contact part 3 to the fitting part 65 using an adhesive agent further.

  In this state, as shown in FIG. 6, the contact portion 3 faces the opening 66 of the bottom wall 61 and appears on the front side of the bottom wall 61. Next, a graphite sheet as the heat conductive member 5 is attached to the contact portion 3. It is preferable to use a graphite sheet having an adhesive layer formed on both sides thereof.

  Next, as shown in FIG. 7, the substrate 2 in which the first thermal element 21 and the second thermal element 22 are formed and the lead wire 9 is connected to the terminal portion 26 is arranged between the pair of substrate positioning walls 63. In addition, the lead wire 9 is disposed in the lead wire holding groove 64 and disposed in the lead wire holding wall 64. In this case, the lead wire 9 is led out in the horizontal direction in parallel with the substrate 2. Further, as shown in FIG. 4, the substrate 2 is attached to the bottom wall 61 using an adhesive 28, and the other surface side at the tip side of the substrate 2 is in contact with the graphite sheet as the heat conductive member 5, The contact portion 3 is thermally coupled.

  Subsequently, the heat insulating member 8 is installed on the surface side of the substrate 2 as shown in FIG. 8, and the lid portion 7 is attached to the base portion 6 as shown in FIG. In the state in which the base portion 6 and the lid portion 7 are combined (see FIG. 1), as shown in FIG. 4 again, the storage space in the case 4 is hermetically sealed, and the heat insulating member is formed by the protruding wall 73 of the lid portion 7. 8 is pressed, and the substrate 2 is pressed toward the bottom wall 61 of the base portion 6 by the heat insulating member 8. For this reason, the substrate 2 comes into close contact with the contact portion 3 via the heat conductive member 5.

  In this case, a heat insulating layer Is-1 of an air layer is formed between the bottom wall 61 and the back surface side of the substrate 2 by the recess 67 formed in the bottom wall 61 of the base portion 6. Further, it can be said that the heat conductive member 5 has a function of appropriately ensuring the space dimension of the heat insulating layer Is-1 according to the thickness dimension thereof.

Further, in the accommodation space of the substrate 2 formed in the case 4, specifically, the space on the surface side of the substrate 2, the heat insulating layer Is-2 of the air layer is similarly formed. In addition, since the heat insulating member 8 disposed in the heat insulating layer Is-2 also has a heat insulating property, it is possible to ensure a good heat insulating state from the periphery of the substrate 2.
Further, the contact portion 3 is exposed by protruding from the outer surface on the back surface side of the bottom wall 61 of the base portion 6 by 0.1 mm to 1 mm, preferably about 0.1 mm.

  Then, the use condition of the deep thermometer which is the heat flow sensor 1 comprised as mentioned above is demonstrated. First, in order to measure the temperature of the deep part of the measurement object, the contact part 3 is brought into contact with the body surface part which is the measurement object. In this case, the contact portion 3 is located on the back side of the substrate 2, and the substrate 2 is disposed in a substantially horizontal direction in the case 4, so that the amount of protrusion of the heat flow sensor 1 can be reduced and easy to handle. Can be. Moreover, since the contact part 3 protrudes about 0.1 mm from the outer surface of the base part 6, the contact part 3 can be made to contact a body surface part reliably.

  The heat of the body surface portion is transmitted to the contact portion 3 and is transmitted to the back surface side of the substrate 2 through the heat conductive member 5. Then, it is detected by the first thermosensitive element 21 positioned facing the contact portion 3, and then flows through the substrate 2 and is detected by the second thermosensitive element 22. In this case, there is a difference between the temperature detected and measured by the first thermal element 21 and the temperature detected and measured by the second thermal element 22, that is, a temperature difference occurs. This change in temperature difference corresponds to a change in heat flux. By measuring this temperature difference, it is possible to measure the heat flux and measure the deep body temperature. Specifically, the data detected and measured by the first thermosensitive element 21 and the data detected and measured by the second thermosensitive element 22 are transmitted to the control unit of the temperature measuring device (not shown) through the lead wire 9, The heat flux is obtained by this control unit, and the body temperature in the deep part is calculated.

  In such temperature measurement, since the contact portion 3 and the first thermosensitive element 21 face each other, heat is easily transferred from the contact portion 3 to the first thermosensitive element 21, and the second thermosensitive element 22 is in contact with the first thermosensitive element 21. Since the heat from the contact portion 3 is not directly transferred away from the portion 3, the temperature difference can be detected with high accuracy.

  Further, the substrate 2 on which the first heat sensitive element 21 and the second heat sensitive element 22 are arranged is hermetically accommodated in a case 4 made of synthetic resin, and is thermally insulated by the heat insulating layers Is-1 and Is-2. Since it is in a state, it is difficult to be affected by the disturbance caused by the surrounding environment such as the ambient temperature, and the resistance to the disturbance can be improved.

  Next, a heat flow sensor according to a second embodiment of the present invention will be described with reference to FIGS. FIG. 10 is a perspective view showing the heat flow sensor, FIG. 11 is a perspective view showing the heat flow sensor as seen from the heat sensitive surface side (back side), and FIG. 12 is a side view showing the case of the heat flow sensor in cross section. FIGS. 13 to 18 are perspective views showing the assembly process together with the configuration of the heat flow sensor. In addition, the same code | symbol is attached | subjected to the same part as 1st Embodiment, or an equivalent part, and the overlapping description is abbreviate | omitted.

The lead-out direction of the lead wire 9 is different between the present embodiment and the first embodiment. That is, in the first embodiment, the lead wire 9 is led out in a substantially horizontal direction parallel to the substrate 2, but in this embodiment, the lead wire 9 is led out in a substantially vertical direction perpendicular to the substrate 2. ing.
Thus, by varying the lead-out direction of the lead wire 9, it becomes possible to meet various needs.

  In the present embodiment, the description will focus on the parts different from the first embodiment, and the description of the same parts as in the first embodiment will be omitted. As shown in FIGS. 10 to 12 and FIGS. 15 to 18, the lead wire 9 is led out in a direction substantially perpendicular to the substrate 2, in other words, in a direction substantially perpendicular to the upper and lower surfaces of the case 4. .

As representatively shown in FIGS. 12 and 18, the lead wire 9 is led out, and a concave portion formed around the lead wire 9 is filled with a material 9 a such as an epoxy resin. . For this reason, the lead wire 9 is led out stably in a substantially vertical direction.
According to the configuration of the present embodiment as described above, the same operational effects as those of the first embodiment can be obtained.

  Next, in order to confirm the performance of each of the above embodiments, an environment similar to the case of measuring the deep temperature of a living body in a simulated manner was created, and temperature measurement was performed. 19 and 20 show a temperature measurement method and its result.

  As shown in FIG. 19, the object to be measured is obtained by laminating an aluminum material M on a heat source H. The temperature of the heat source H is set to 42 ° C., and an aluminum material M having a thickness of 2 mm is laminated. . The temperature was measured by pressing the contact portion 3 of the heat flow sensor 1 against the surface of the aluminum material M.

  The result is as shown in the graph of “heat source temperature and calculated value of heat flow sensor” in FIG. In FIG. 20, the horizontal axis represents time [S (seconds)], and the vertical axis represents temperature [° C.]. The detected temperature of the second thermosensitive element 22 is slightly lower than the detected temperature of the first thermosensitive element 21, and a temperature difference is generated. Based on this temperature difference, the control unit obtains the heat flux and calculates the body temperature at the deep part. The calculated value (temperature [° C.]) rises sharply in about 10 seconds from the start of measurement, and shows 42 ° C.

  On the other hand, the temperature of the heat source H is set to 42 ° C. Therefore, the calculated value and the temperature of the heat source H coincide with each other at a fast response speed, and it can be confirmed that the body temperature in the deep part is immediately calculated.

Next, a heat flow sensor according to a third embodiment of the present invention will be described with reference to FIGS. FIG. 21 is a side view showing a cross section of the case of the heat flow sensor according to the first embodiment. FIG. 22 is a side view showing a cross section of the case of the heat flow sensor according to the second embodiment. In addition, the same code | symbol is attached | subjected to the part which is the same as that of 1st Embodiment, or an equivalent part, and the overlapping description is abbreviate | omitted.
Example 1

  As shown in FIG. 21, in this embodiment, the substrate 2 on which the first thermal element 21 and the second thermal element 22 are formed is disposed in an inclined manner in the housing space of the case 4. Accordingly, a protruding base 61a having an inclined surface is formed to protrude from the bottom wall 61 of the base portion 6 to which the substrate 2 is bonded, and the opposing surface of the contact portion 3 facing the first thermal element 21 is formed on the inclined surface. ing.

According to such a configuration, when the contact portion 3 is brought into contact with the body surface portion that is the measurement object in the usage state of the deep thermometer that is the heat flow sensor 1, the contact portion 3 is located on the back side of the substrate 2. Since the substrate 2 is disposed in an inclined manner in the case 4, the amount of protrusion of the heat flow sensor 1 can be reduced, and the heat insulating layer of the air layer between the bottom wall 61 and the back surface side of the substrate 2. It becomes possible to ensure a large space dimension of Is-1. Further, the same effects as those of the first embodiment can be achieved.
(Example 2)

As shown in FIG. 22, in this embodiment, the contact portion 3 is formed to be inclined to the end surface of the substrate 2, and has an inclined surface S that is inclined with respect to the surface direction of the substrate 2. ing. Since such a contact portion 3 is positioned so as to face one of the temperature sensors, heat is easily transmitted from the contact portion 3 to the first thermal element 21. Further, the substrate 2 is disposed in an inclined manner in the accommodation space of the synthetic resin case 4.

  Therefore, in addition to being able to achieve the same operational effects as in the first embodiment, the contact portion 3 is formed integrally with the substrate 2, so that heat is easily transmitted to the first thermal element 21, and the component The score can be reduced.

  In each of the above embodiments, the number of heat sensitive elements as temperature sensors is not limited to two, and three or more may be arranged on the substrate 2. For example, it is possible to arrange a first heat sensitive element, a second heat sensitive element, a third heat sensitive element, and the like. In this case, the thermal elements are arranged at regular intervals or at intervals in an exponential positional relationship. This can be expected to improve the temperature measurement accuracy.

  The present invention is not limited to the configuration of each of the embodiments described above, and various modifications can be made without departing from the spirit of the invention. Moreover, each said embodiment is shown as an example and is not intending limiting the range of invention.

For example, the heat flow sensor of this embodiment can be applied to the case where the deterioration information is detected by measuring the temperature of the deep part of a secondary battery, a fuel cell, or a solar cell. Furthermore, the present invention can be applied to the detection of the heat flow of soil such as farmland and cultured soil, and the measurement of the heat flux of building materials such as concrete, wood and heat insulating materials.
Moreover, as a temperature sensor, a thermocouple, a thermopile, a thermistor, a resistance temperature detector, a semiconductor temperature sensor, etc. can be applied, and the means is not particularly limited.

  Furthermore, the heat insulating layer for insulating the substrate is not limited to the case where it is formed by an air layer. A heat insulating layer may be formed by filling the air layer with a heat insulating material.

DESCRIPTION OF SYMBOLS 1 ... Heat flow sensor 2 ... Board | substrate 3 ... Contact part 4 ... Case 5 ... Thermally conductive member (graphite sheet)
6 ... Base part 7 ... Cover part 8 ... Thermal insulation member 9 ... Lead wire 21 ... Temperature sensor (first thermal element)
22 ... Temperature sensor (second thermal element)
Is-1, Is-2 ... heat insulation layer 24 ... wiring patterns 25, 26 ... terminal portion 27 ... protective film

Claims (4)

A substrate,
At least two temperature sensors disposed at a predetermined interval on one side of the substrate;
A contact portion formed on the end surface of the substrate and inclined to be opposed to one of the temperature sensors;
A case made of synthetic resin in which the substrate is housed in an inclined manner;
A heat flow sensor comprising: A substrate,
Three or more temperature sensors disposed at a predetermined interval on one side of the substrate ;
A contact portion positioned opposite to one of the temperature sensors on the other side of the substrate;
A heat flow sensor comprising: 3. The heat flow sensor according to claim 1, wherein the substrate has a thermal conductivity of 0.1 W / m · K to 500 W / m · K. 4. The heat flow sensor according to any one of claims 1 to 3, wherein the contact portion protrudes from an outer surface of the case by 0.1 mm to 1 mm.

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