JPH08138906A - Manufacture of positive temperature coefficient(ptc) thermistor device and heat detecting device - Google Patents

Abstract

PURPOSE: To obtain a PTC thermistor device having a very low resistance value at normal temperature as low as 20mΩ or lower, for example, which was absolutely unable to accomplish before. CONSTITUTION: A PTC thermistor element 11 is a flat sheet material of 0.4mm in thickness, and electrodes 12 and 13 are provided on both faces. A recessed part 22, which is connected to the outside part on a flat surface 21, is provided on a supporting substrate 2, and the electrode 12 of a PTC thermistor element 1 is surface-junctioned to the flat surface 21. When the PTC thermistor element 11 is going to be manufactured, its one surface side is surface-junctioned to a supporting substrate 1, then other surface of the PTC thermistor element 11 is polished, and other electrode 12 is formed on the polished surface of the PTC thermistor element.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a positive temperature coefficient thermistor device, a heat detecting device and a method of manufacturing a positive temperature coefficient thermistor device.

[0002]

2. Description of the Related Art For example, as a heat detecting device for detecting ignition of a gas combustor or for detecting overheating, a small thermoelectromotive force such as 15 to 20 mV generated by a thermocouple is used and a negative characteristic thermistor device is used. A technique using a heat-sensitive element made of is known. In the negative characteristic thermistor device, the resistance value decreases as the temperature rises, and the circuit current tends to increase.Therefore, in the heat detection device using this, the circuit current has a certain level in order to generate the heat detection signal. It is essential to add an external circuit that detects the arrival and then drives the switch. Therefore, the configuration of the heat detection device becomes complicated.

As another example of the heat sensitive element, a positive temperature coefficient thermistor device is well known. The PTC thermistor device is
It has a switching characteristic in which the resistance value rapidly increases as the temperature rises. Therefore, by combining the thermocouple and the positive temperature coefficient thermistor device, the positive temperature coefficient thermistor device is used as a heat-sensitive element, and the thermoelectromotive force of the thermocouple is used as the operating power source of the positive temperature coefficient thermistor device, so that By utilizing the characteristics, it is possible to realize a heat detection device having a simple circuit configuration that does not require a level detection circuit or a switch circuit. However, the PTC thermistor device used for such an application must have an extremely low room temperature resistance value of several tens mΩ or less because the thermoelectromotive force of the thermocouple is a minute value such as 15 to 20 mv. . It is known that the room temperature resistance value R of the positive temperature coefficient thermistor device is determined by the specific resistance value ρ, the thickness t, and the plane area S. For example, assuming a disc-shaped PTC thermistor device that is often used, t = 0.0785D ² R / ρ where D is the diameter of the PTC thermistor device. In this disc-shaped positive temperature coefficient thermistor device, D
= 20 mm and ρ = 10 Ω-cm, in order to obtain a room temperature resistance value of 20 mΩ, the thickness t of the positive temperature coefficient thermistor element is t
Is 0.063 mm from the above formula. A PTC thermistor device having such a thickness t is at a level at which it can be damaged only by touching a hand or an instrument for handling or processing, and it is extremely difficult to actually obtain it.
For this reason, it was not possible to realize a heat detection device in which the PTC thermistor device was combined with a thermocouple.

The technique disclosed in Japanese Utility Model Publication No. 1-215524 is known as a technique for obtaining a thin type positive temperature coefficient thermistor device. However, the positive temperature coefficient thermistor device described in this prior art document is premised on that lead wires can be attached and it has a thickness that can withstand the processing conditions, and the achievable thickness is 1 to 0.4 mm. Is. Therefore, the minimum room temperature resistance value calculated from the above formula is 127.4.
It was mΩ.

Further, Japanese Utility Model Publication No. 1-21524 discloses a positive temperature coefficient thermistor device for limiting current, but does not disclose a positive temperature coefficient thermistor device suitable as a heat sensitive element. In particular, regarding the reinforcing layer and the adhesive for bonding the positive temperature coefficient thermistor element, the heat conduction efficiency that must be considered when used as a heat sensitive element is not sufficiently considered, and a structure suitable for the heat sensitive element is not provided. It was not disclosed.

[0006]

SUMMARY OF THE INVENTION The object of the present invention is to provide a positive temperature coefficient thermistor device having an extremely low room temperature resistance value of, for example, 20 mΩ or less, which has heretofore been unattainable, and a heat detecting device using the thermistor device. It is to be.

Another object of the present invention is to provide a positive temperature coefficient thermistor device capable of reliably preventing damage to the extremely thin positive temperature coefficient thermistor element having an extremely low room temperature resistance value as described above, and a heat detecting device using the same. Is to provide.

Still another object of the present invention is to provide a positive temperature coefficient thermistor device suitable as a heat sensitive element and a heat detecting device using the same.

Still another object of the present invention is to improve the heat conduction efficiency of the adhesive layer between the positive temperature coefficient thermistor element and the support that supports the positive temperature coefficient thermistor element and improve the compatibility as a heat sensitive element. A thermistor device and a heat detection device using the thermistor device.

Still another object of the present invention is to provide a positive temperature coefficient thermistor device and a positive temperature coefficient thermistor device which can perform a sufficient heat detecting function even when a small thermoelectromotive force generated by a thermoelectromotive force element is used as an operating power source. The present invention is to provide a heat detecting device.

Still another object of the present invention is to provide a heat detecting device having a simple circuit configuration which can omit the level detecting circuit and the switch circuit.

Still another object of the present invention is to provide a positive characteristic that the thickness of the positive characteristic thermistor element can be surely polished to a range of 0.01 mm to 0.4 mm without causing damage to the positive characteristic thermistor element. A method of manufacturing a thermistor device is provided.

[0013]

In order to solve the above problems, a positive temperature coefficient thermistor device according to the present invention includes a positive temperature coefficient thermistor element and a supporting substrate. The PTC thermistor element includes a PTC thermistor element body and at least two electrodes, the PTC thermistor element body is a flat plate material having a thickness of 0.4 mm or less, and the two electrodes are the The positive temperature coefficient thermistor is provided on both sides in the thickness direction of the element body. The support substrate has at least one flat surface, a recess extending to the outside is provided on the flat surface, and one of the electrodes is surface-bonded to the flat surface.

Preferably, the positive temperature coefficient thermistor body has a thickness of 0.01 mm or more. The recess may be a hole penetrating in the thickness direction of the PTC thermistor body or a groove formed on the flat surface of the PTC thermistor body.

Next, the heat detecting device according to the present invention includes a thermoelectromotive element and a heat sensitive element. The thermoelectromotive force element is arranged near the heat source to be detected together with the thermosensitive element. The thermosensitive element is the above-described positive temperature coefficient thermistor device according to the present invention, and is connected to the thermoelectromotive element so that the thermoelectromotive force generated in the thermoelectromotive element is used as an operating power source.

Further, in the method for manufacturing a PTC thermistor device according to the present invention, after the one surface of the PTC thermistor element body having an electrode on one surface is surface-bonded to the flat surface provided on the supporting substrate, The other surface of the PTC thermistor body is polished, and then another electrode is formed on the polished surface of the PTC thermistor body.

[0017]

In the PTC thermistor element included in the PTC thermistor device according to the present invention, the PTC thermistor element is a flat plate material having a thickness of 0.4 mm or less. A positive temperature coefficient thermistor element having such a thickness has a thickness that could not be achieved in the past, and as a result, a positive temperature coefficient which has an extremely low room temperature resistance value of, for example, 20 mΩ or less, which could not be realized in the past. A thermistor device can be obtained. A positive temperature coefficient thermistor device having such a low room temperature resistance value is, for example, 15 to 20 generated by a thermocouple.
In a heat detecting device using a micro thermoelectromotive force such as mv as an operating power source, a sufficient heat sensitive function can be achieved even when used as a heat sensitive element.

The support substrate has at least one flat surface, and one electrode of the positive temperature coefficient thermistor element is surface-bonded to the flat surface. Due to this structure, the supporting substrate functions as a reinforcing member for the PTC thermistor element, thereby preventing damage to the PTC thermistor element body.

Since the supporting substrate is provided with a recess extending outwardly on the flat surface, when the positive temperature coefficient thermistor element is bonded to the flat surface of the supporting substrate, a gap between the supporting substrate and the positive temperature coefficient thermistor element is formed. Air and volatile components that may be generated at the interface or in the bonding agent are released to the outside through the recess. Therefore, it is possible to avoid a situation in which air is present between the support substrate and the PTC thermistor element to deteriorate heat conduction or reduce adhesive strength. This allows
A positive temperature coefficient thermistor device suitable as a heat sensitive element can be obtained. In addition, it is possible to improve the heat conduction efficiency of the adhesive layer between the positive temperature coefficient thermistor element and the support body that supports the positive temperature coefficient thermistor element, and improve the suitability as a heat sensitive element.

Next, the heat detecting device according to the present invention includes a thermosensitive element which is the above-mentioned positive temperature coefficient thermistor device according to the present invention, and the thermosensitive element utilizes thermoelectromotive force generated in the thermoelectromotive element as an operating power supply. As described above, since it is connected to the thermoelectromotive force element, it includes all the advantages of the positive temperature coefficient thermistor device and can utilize the switch characteristics of the positive temperature coefficient thermistor device to omit the level test circuit and the switch circuit. A heat detection device having a simple circuit configuration can be realized.

Further, in the method for manufacturing a positive temperature coefficient thermistor device according to the present invention, one surface of the positive temperature coefficient thermistor element body having electrodes on the entire surface is bonded to a flat surface provided on the supporting substrate, Since the other surface of the characteristic thermistor element body is polished and then another electrode is formed on the polished surface of the positive characteristic thermistor element body, in the polishing step of the positive characteristic thermistor element body that needs to be processed extremely thin, It is possible to polish the thickness of the positive temperature coefficient thermistor body to a range of 0.01 mm to 0.4 mm while preventing the characteristic thermistor body from being damaged by the supporting substrate.

[0022]

1 is a plan view of a PTC thermistor device according to the present invention, and FIG. 2 is a sectional view of the PTC thermistor device shown in FIG. The PTC thermistor device according to the present invention includes a PTC thermistor element 1 and a support substrate 2.
The PTC thermistor element 1 includes a PTC thermistor element body 11
And at least two electrodes 12, 13.
The PTC thermistor element body 11 is a flat plate material having a thickness t1 of 0.4 mm or less. The positive temperature coefficient thermistor body 11 should be as thin as possible for the purpose of obtaining a low room temperature resistance value, but the room temperature resistance value actually required and the difficulty of manufacturing that increases with the reduction in thickness are taken into consideration. Then, the lower limit of the thickness is about 0.01 mm. A typical example of the PTC thermistor element body 11 is a PTC semiconductor ceramic containing barium titanate as a main component.

The two electrodes 12 and 13 are provided on both surfaces 111 and 112 in the thickness direction of the PTC thermistor element body 11, respectively. Of the two electrodes 12, 13, the electrode 12
May cover the entire surface 111 on which it is provided, or may have a gap around the electrodes. The other electrode 13 has an edge of the surface 112 on which it is provided,
The surface 11 is formed such that a gap G1 is formed between the electrode 11 and the edge.
It is desirable to be provided in the inside of 2.

The support substrate 2 has at least one flat surface 2
1 and a concave portion 22 is formed on the flat surface 21 and extends to the outside, and one of the electrodes of the positive temperature coefficient thermistor element 1 has a flat surface 2
1 is surface-joined.

FIG. 3 is a plan view of the support substrate 2 shown in FIGS. 1 and 2, and FIG. 4 is a sectional view taken along line A4-A4 of FIG. The illustrated recess 22 is provided as a hole penetrating in the thickness direction of the support substrate 2. The number of holes forming the recess 22, the hole diameter, and the forming position are not limited to those shown in the drawing, but may be variously changed. As an example, when the support substrate 2 having a diameter of 20 mm is used, the holes forming the recesses 22 have a hole diameter of 0.5 to 1.5 mm and the number of holes is 20 to 40.
Can be formed on the flat surface 21 so as to have a substantially uniform distribution.

The recess 22 can take various forms other than the embodiment shown in FIGS. An example is shown in FIG.
It shows in FIG. In the embodiment shown in FIGS. 5 and 6, the recess 22 is a groove formed on the flat surface 21 of the support substrate 2. A plurality of grooves forming the recess 22 are provided, and each of the grooves is a support substrate 2 formed in a disc shape.
The grooves radially extend from the central portion of the core to the outer peripheral direction and are arranged at substantially constant angles.

Next, in the embodiment shown in FIGS. 7 and 8, the recess 22 includes a plurality of radially arranged grooves and a plurality of circular grooves continuous with the grooves. . The circular grooves are coaxially arranged at intervals.

As described above, the PTC thermistor element 1 included in the PTC thermistor device according to the present invention is a flat plate material in which the thickness t1 of the PTC thermistor body 11 is 0.4 mm or less. The positive temperature coefficient thermistor element body 11 having such a thickness t1 has a thickness that could not be achieved in the past, and as a result, it has a very low room temperature resistance value of 20 mΩ or less, which could not be realized in the past. A characteristic thermistor device can be obtained. The PTC thermistor device having such a low room temperature resistance value has a sufficient thermosensitive function as a thermosensitive element which directly uses a small thermoelectromotive force such as 15 to 20 mV generated by a thermocouple as an operating power source. You can

The support substrate 2 has at least one flat surface 2
1 and one electrode 12 of the positive temperature coefficient thermistor element 1 is surface-bonded on the flat surface 21. Because of this structure,
The support substrate 2 functions as a reinforcing member for the PTC thermistor element 1.

Since the supporting substrate 2 is provided with the recess 22 continuous to the outside on the flat surface 21, when the positive temperature coefficient thermistor element 1 is bonded onto the flat surface 21 of the supporting substrate 2, the supporting substrate 2 and the positive substrate 2 are connected to each other. Air and volatile components that may be generated in the contact interface with the characteristic thermistor element 1 or in the bonding agent are released to the outside through the recess 22. Therefore, it is possible to avoid a situation in which air is present between the support substrate 2 and the positive temperature coefficient thermistor element 1 to deteriorate heat conduction or reduce adhesive strength. As a result, a positive temperature coefficient thermistor device suitable as a heat sensitive element can be obtained. Further, it is possible to improve the heat conduction efficiency of the adhesive layer between the positive temperature coefficient thermistor element 1 and the support that supports the positive temperature coefficient thermistor element 1, and improve the suitability as a heat sensitive element.

In the embodiment, the positive temperature coefficient thermistor element body 1
Of the two electrodes 12, 13 respectively provided on both surfaces 111, 112 in the thickness direction of 1, the electrode 12 covers the entire surface 111 on which it is provided, and is provided on the support substrate 2. It is surface-bonded to the flat surface 21. Due to this structure, the PTC thermistor element body 11 does not form a gap due to the thickness t2 of the electrode 12 between the PTC thermistor element body 11 and the flat surface 21 of the support substrate 2 regardless of the presence of the electrode 12. Is closely joined to the flat surface 21 of the. As a result, the thickness t1 of the PTC thermistor element body 11 is set to 0.
Even if the value is set to 4 mm or less, the PTC thermistor element body 1 can be reliably prevented from being damaged.
Moreover, since the electrode 12 covers the entire surface 111 on which the electrode 12 is provided, the electrode 12 can be easily pulled out to the outside.

Further, in the embodiment, two electrodes 12,
The other electrode 13 out of 13 is provided in the surface such that a gap G1 is formed between the edge of the surface 112 on which it is provided and the electrode edge. Since the PTC thermistor element body 11 is set to have a thickness t1 of 0.4 mm or less, a short circuit between electrodes is likely to occur due to adhesion of minute dust or the like in the gap in the thickness direction. On the other hand, when the gap G1 is provided between the edge of the surface 112 of the PTC thermistor element body 11 and the electrode edge, the PTC thermistor element body 11 becomes 0.
Despite being set to a minute thickness t1 of 4 mm or less, a short circuit between electrodes can be prevented. Further, the gap G1 can increase the creepage distance between the electrodes 12 to 13 to secure a necessary withstand voltage.

The illustrated electrodes 12 and 13 are ohmic electrode layers 121 and 13 attached to the PTC thermistor element body 11.
Including 1. The ohmic electrode layer can be formed as a Ni electroless plating film or a vapor deposition film of Ni or Ni-Cr. Preferably, the electrodes 12 and 13 are the ohmic electrode layer 1.
21 and 131, and an electrode layer 122 containing silver as a main component,
132 are stacked. With such an electrode structure, the ohmic electrode layers 121 and 131 sufficiently take out the positive resistance temperature characteristic of the positive temperature coefficient thermistor element body 11 to the outside, and the ohmic electrode layers 121 and 131
The characteristic deterioration of 131 is caused by the electrode layer 122 containing silver as a main component,
This can be prevented by 132, and the surface resistance of the electrodes 12, 13 can be reduced.

When used as a heat sensitive element, the support substrate 2 is made of a material having good thermal conductivity. As long as it is such a material, it may be an electrically insulating material or a conductive material. Examples of the electrically insulating material having a good thermal conductivity that constitutes the support substrate 2 include high alumina porcelain and silicon nitride porcelain. When the support substrate 2 is made of an electrically insulating material, at least the surface to which the positive temperature coefficient thermistor element 1 is bonded may be covered with a metal film. This allows
The thermal conductivity of the support substrate 2 is further improved, and the metal film provided on the support substrate 2 can be used as a terminal conductor for extracting the electrodes 12 and 13 to the outside. An example of such a metal film is nickel or copper. When the support substrate 2 is made of a conductive material, examples of such a conductive material include copper alloy and stainless steel.

When bonding the PTC thermistor element 1 to the support substrate 2, an adhesive having good thermal conductivity is used, or after the electrode layer 122 constituting the electrode 12 is applied and before curing. The positive temperature coefficient thermistor element 1 can be positioned at a predetermined position on the support substrate 21, and the positive temperature coefficient thermistor element 1 can be surface-bonded onto the support substrate 2 by utilizing the baking adhesive force of the electrode layer 122. Here, when the PTC thermistor element 1 is bonded to the flat surface of the support substrate 2, air or volatilization that may occur in the contact interface between the support substrate 2 and the PTC thermistor element 1 or in the bonding agent. The components are released to the outside through the recesses 22 by the air and volatile component releasing action of the recesses 22. Therefore, the support substrate 2
It is possible to avoid a situation in which air intervenes between the positive temperature coefficient thermistor element 1 and the PTC thermistor element 1 to deteriorate heat conduction or decrease the adhesive strength. As a result, a positive temperature coefficient thermistor device suitable as a heat sensitive element can be obtained.

The positive temperature coefficient thermistor device according to the present invention can take various forms. Examples thereof are shown in FIGS. 9 to 12. 9 is a plan view showing another embodiment of the positive temperature coefficient thermistor device according to the present invention, and FIG. 10 is a sectional view taken along the line A10-A10 in FIG. In this embodiment, the electrode 12 passes through the side surface of the PTC thermistor element body 11 and is guided to the upper surface side thereof. A gap G2 is provided between the lead electrode portion 123 guided to the upper surface and the electrode 13. With such a structure, the electrode 12 can be easily pulled out to the outside. The recess 22 is formed by a hole penetrating the support substrate 2 in the thickness direction, but may be a groove as shown in FIGS. 5 to 8.

FIG. 11 is a plan view showing another embodiment of the positive temperature coefficient thermistor device according to the present invention, and FIG. 12 is A12 of FIG.
It is a cross-sectional view taken along the line A12. In this example,
A through hole 124 is provided in the center of the support substrate 2. The electrode 12 passes through the inside of the through hole 124 and is guided to the upper surface side of the PTC thermistor element body 11. A gap G3 is provided between the lead electrode portion 123 guided to the upper surface and the electrode 13. With such a structure, the electrode 12 can be easily pulled out to the outside. The concave portion 22 is formed by a hole penetrating the supporting substrate 2 in the thickness direction.
It may be a groove as shown in FIG.

FIG. 13 is an electric circuit diagram showing the structure of the heat detecting device according to the present invention. The heat detecting device according to the present invention includes the thermosensitive element 3 and the thermoelectromotive force element 4 which are the positive temperature coefficient thermistor device according to the present invention shown in FIGS. The thermosensitive element 3 is connected in series with the thermoelectromotive element 4 so that the thermoelectromotive force generated in the thermoelectromotive element 4 is used as an operating power source. With such a configuration, in addition to including all the advantages of the positive temperature coefficient thermistor device,
With the heat-sensitive element 3 utilizing the switch characteristic of the positive temperature coefficient thermistor device, it is possible to realize a heat detecting device having a simple circuit configuration that does not require a level verification circuit or a switch circuit. The thermoelectromotive force element 4 is typically a thermocouple.

FIG. 14 is a diagram showing the structure of a combustion device using the heat detecting device according to the present invention, and FIG. 15 is an electric circuit diagram thereof. In FIG. 14 and FIG. 15, the heat sensitive element 3 constituting the heat detection device according to the present invention is arranged in contact with the bottom of the object 5 to be heated such as a pot, and the thermoelectromotive force element 4 is provided from the combustor 6 such as a gas stove. It is arranged so as to generate an electromotive force by receiving the heat of the generated flame 61. The combustor 6 is supplied with gas through a gas control valve 81 such as an electromagnetic valve and the nozzle 9 to perform a combustion operation. The gas control valve 81 is controlled by the heat detection device according to the present invention, has a manually operated ignition function, and is electromagnetically adsorbed after ignition and maintains an open state. The control circuit 7 opens the gas control valve 81 when a signal based on the electromotive force of the thermoelectromotive force element 4 is given from the heat detection device. Before the ignition operation and when there is no signal from the heat detecting device, the gas control valve 81 is in the shut-off state.
The illustrated control circuit 7 has a solenoid 70 which is a part of the gas control valve 81, and is integrated with the gas control valve 81.

In the combustion apparatus shown in FIGS. 14 and 15, when the combustor 6 is ignited, the thermoelectromotive force element 4 causes the flame 61
To generate thermoelectromotive force. Since the temperature of the article to be heated 5 is room temperature at the time of ignition, the resistance value of the heat sensitive element 3 is a minute value of about 20 mΩ described above. Therefore, due to the thermoelectromotive force generated in the thermoelectromotive force element 4, the low-sensitivity thermosensitive element 3
An electric current flows through it. Based on this current, the control circuit 7
Opens the gas control valve 81. After ignition, the gas control valve 81 opens and holds the gas for combustion through the gas control valve 81 to the combustor 5, thereby maintaining the combustion operation of the combustor 5.

By the combustion operation of the combustor 5, the object to be heated 5
Is heated, and as a result, the temperature of the object to be heated 5 rises. Since the thermosensitive element 3 is provided in contact with the surface of the article to be heated 5, as the temperature of the article to be heated 5 rises, the temperature of the thermosensitive element 3 rises and the resistance value of the thermosensitive element 3 increases. The thermosensitive element 3 does not cause a sudden change in the resistance value in the temperature range due to the normal combustion operation, and controls the current for maintaining the opening of the gas control valve 81 by the thermoelectromotive force supplied from the thermoelectromotive force element 3. It should have a resistance temperature characteristic that can be supplied to the circuit 7. As a result, the heat-sensitive element 3 can avoid the switch operation in the normal combustion operation.

When the object 5 to be heated is, for example, in an empty state, the temperature of the object 5 to be heated rises significantly above the temperature during normal combustion operation. For this reason, the temperature of the heat sensitive element 3 rises to a region where the resistance value rapidly increases, and the heat sensitive element 3 undergoes a switching operation that sharply narrows the current supplied from the heat detection device to the control circuit 7. As a result, the opening control from the control circuit 7 to the gas control valve 81 is lost, the gas control valve 81 is shut off, and accordingly, the combustion operation of the combustor 6 is stopped.

16 to 19 show a method of manufacturing the positive temperature coefficient thermistor device according to the present invention. First, as shown in FIG. 16, one surface 111 of the positive temperature coefficient thermistor body 11 having the electrode 12 on the entire surface is bonded to the flat surface 21 provided on the support substrate 2. The support substrate 2 has a structure as shown in FIGS. The support substrate 2 to which the PTC thermistor element body 11 is bonded is fixed on the jig 200.

Next, as shown in FIG. 17, the other surface of the PTC thermistor element body 11 is polished by using a polishing apparatus 300. The polishing apparatus 300 is, for example, axially rotated as indicated by arrow O1 and is moved in the direction of arrow X1 or X2.
As a result, as shown in FIG. 18, the PTC thermistor element body 11 is polished by Δt1, and the PTC thermistor element body 11 is polished.
The required thickness t1 is set to 0.01 to 0.4 mm.

Next, as shown in FIG. 19, another electrode 13 is attached to the polished surface 112 of the positive temperature coefficient thermistor body 11.
It is formed by means such as vapor deposition or sputtering.

Through the above manufacturing method, it is ensured that the thickness t1 of the PTC thermistor body 11 is in the range of 0.01 to 0.4 mm while preventing the PTC thermistor body 11 from being damaged. It can be polished. Although illustration is omitted, when electroless plating or the like is used as a method of forming the electrodes 12 and 13, a step of removing the electrode film attached to the outer periphery is added.

The above manufacturing method is applied to the method of manufacturing the positive temperature coefficient thermistor device shown in FIGS. 1 and 2, but also in the case of manufacturing the positive temperature coefficient thermistor device shown in FIGS. It is obvious to those skilled in the art that the same application is possible with a slight modification.

[0048]

As described above, according to the present invention, the following effects can be obtained. (A) For example, 2 which could not be realized in the past
It is possible to provide a positive temperature coefficient thermistor device having an extremely low room temperature resistance value of 0 mΩ or less and a heat detection device using the thermistor device. (B) It is possible to provide a positive temperature coefficient thermistor device that can reliably prevent damage to the extremely thin positive temperature coefficient thermistor body having an extremely low room temperature resistance value as described above, and a heat detection device using the same. (C) It is possible to provide a positive temperature coefficient thermistor device suitable as a heat-sensitive element and a heat detection device using the thermistor device. (D) A PTC thermistor device and a heat detecting device using the PTC thermistor device, in which the heat conduction efficiency of the adhesive layer between the PTC thermistor element and the support supporting the PTC thermistor element is improved, and the compatibility as a heat-sensitive element is improved. Can be provided. (E) It is possible to provide a positive temperature coefficient thermistor device and a heat detection device using the same, which can perform a sufficient heat detection function even when a small thermoelectromotive force generated by a thermoelectromotive force element is used as an operating power supply. . (F) It is possible to provide a heat detection device having a simple circuit configuration that can omit the level verification circuit and the switch circuit. (G) Without causing damage to the PTC thermistor body,
It is possible to provide a method for manufacturing a PTC thermistor device capable of reliably polishing the PTC thermistor body to a thickness of 0.4 mm or less.

[Brief description of drawings]

FIG. 1 is a plan view of a positive temperature coefficient thermistor device according to the present invention.

FIG. 2 is a cross-sectional view taken along the line A2-A2 of FIG.

3 is a plan view of a support substrate used in the PTC thermistor device shown in FIGS. 1 and 2. FIG.

FIG. 4 is a cross-sectional view taken along the line A4-A4 in FIG.

FIG. 5 is a plan view of a support substrate used in the positive temperature coefficient thermistor device according to the present invention.

6 is a cross-sectional view taken along the line A6-A6 of FIG.

FIG. 7 is a plan view showing another embodiment of the support substrate used in the positive temperature coefficient thermistor device according to the present invention.

8 is a cross-sectional view taken along the line A8-A8 in FIG.

FIG. 9 is a plan view of another embodiment of the positive temperature coefficient thermistor device according to the present invention.

10 is a cross-sectional view taken along the line A10-A10 in FIG.

FIG. 11 is a plan view of still another embodiment of the positive temperature coefficient thermistor device according to the present invention.

12 is a cross-sectional view taken along the line A12-A12 of FIG.

FIG. 13 is a diagram showing a configuration of a heat detection device according to the present invention.

FIG. 14 is a diagram showing a configuration of a combustion device using the heat detection device according to the present invention.

15 is an electric circuit diagram of the combustion device shown in FIG.

FIG. 16 is a diagram showing a method of manufacturing the positive temperature coefficient thermistor device according to the present invention.

FIG. 17 is a diagram showing the method of manufacturing the positive temperature coefficient thermistor device according to the present invention, which is subsequent to the step of FIG. 16;

FIG. 18 is a diagram showing a method of manufacturing the positive temperature coefficient thermistor device according to the present invention, following the step of FIG. 17;

FIG. 19 is a diagram showing a method of manufacturing the positive temperature coefficient thermistor device according to the present invention, following the step of FIG. 18;

[Explanation of symbols]

 1 PTC Thermistor Element 11 PTC Thermistor Element 12, 13 Electrode 2 Support Substrate 22 Recess

Claims (16)

[Claims] 1. A PTC thermistor device including a PTC thermistor element and a support substrate, wherein the PTC thermistor device includes a PTC thermistor element body and at least two electrodes, The positive temperature coefficient thermistor element is a flat plate material having a thickness of 0.4 mm or less, the two electrodes are provided on both sides in the thickness direction of the positive temperature coefficient thermistor element, and the support substrate is at least one. A positive temperature coefficient thermistor device having two flat surfaces, a recess extending outward from the flat surface, and one of the electrodes of the positive temperature coefficient thermistor element being surface-bonded to the flat surface. 2. The positive temperature coefficient thermistor device according to claim 1, wherein the positive temperature coefficient thermistor element body has a thickness of 0.01 mm or more. 3. The positive temperature coefficient thermistor device according to claim 1, wherein the recess is a hole penetrating in a thickness direction of the support substrate. 4. The PTC thermistor device according to claim 1, wherein the recess is a groove formed on the flat surface of the support substrate. 5. The PTC thermistor device according to claim 1, wherein the electrode includes an ohmic electrode layer attached to the PTC thermistor body. 6. The positive temperature coefficient thermistor device according to claim 5, wherein the ohmic electrode layer is a Ni electroless plating film or N.
A positive temperature coefficient thermistor device which is a vapor deposited film of i or Ni-Cr. 7. The positive temperature coefficient thermistor device according to claim 5, wherein the electrode has an electrode layer containing silver as a main component laminated on the ohmic electrode layer. 8. The positive temperature coefficient thermistor device according to claim 1, wherein the support substrate is made of a material having good thermal conductivity. 9. The PTC thermistor device according to claim 8, wherein the support substrate is made of an electrically insulating material. 10. The PTC thermistor device according to claim 9, wherein the support substrate is made of high alumina porcelain or silicon nitride porcelain. 11. The PTC thermistor device according to claim 8, wherein the support substrate has conductivity. 12. The positive temperature coefficient thermistor device according to claim 11, wherein the support substrate is entirely made of a conductive material. 13. The positive temperature coefficient thermistor device according to claim 11, wherein the support substrate is made of an electrically insulating material, and at least a surface for bonding the positive temperature coefficient thermistor element is covered with a conductive film. Positive temperature coefficient thermistor device. 14. A heat detection device including a thermoelectromotive element and a thermosensitive element, wherein the thermosensitive element is the positive temperature coefficient thermistor device according to any one of claims 1 to 13, wherein: A heat detection device connected to the thermoelectromotive element so that the thermoelectromotive force generated in the element is used as an operating power source. 15. The heat detecting device according to claim 14, wherein the thermoelectromotive force element is a thermocouple. 16. A method of manufacturing a positive temperature coefficient thermistor device including a positive temperature coefficient thermistor element and a supporting substrate, wherein a positive temperature coefficient thermistor element body having an electrode on one surface is provided on a flat surface provided on the supporting substrate. After joining one surface,
A method of manufacturing a positive temperature coefficient thermistor device, comprising polishing the other surface of the positive temperature coefficient thermistor body, and thereafter forming another electrode on the polished surface of the positive temperature coefficient thermistor body.