Heater device

Abstract

The heater device has a heater surface (10a) facing one side of a direction (Dt), and radiates heat from the heater surface. In addition, the heater device includes: a transmitting electrode (30) and a receiving electrode (40) arranged on the other side of the above-mentioned one direction relative to the heater surface; and an insulating covering layer (54) covering the transmitting electrode and the receiving electrode on one side of the above-mentioned one direction relative to the transmitting electrode and the receiving electrode. The transmitting electrode and the receiving electrode are electrically connected to a contact detection unit (71), and the contact detection unit detects contact or proximity of an object (2) relative to the heater surface by a change in electrostatic capacitance between the transmitting electrode and the receiving electrode. The insulating covering layer has a first component (541) composed of an insulating object (541a) having electrical insulation and a second component (542) having a smaller relative dielectric constant than the first component. The second component is located between at least one of the transmitting electrode and the receiving electrode and the heater surface.

Description

[0001] Cross-reference to related applications

[0002] This application is based on Japanese Patent Application No. 2019-207950 filed on November 18, 2019, the contents of which are incorporated herein by reference. Technical Field

[0003] The present invention relates to a heater device for radiating heat from a heater surface. Background Art

[0004] As such a heater device, there is conventionally known a heater device described in Patent Document 1, for example. The heater device described in Patent Document 1 includes a heater body that generates heat and a detection electrode for detecting approach or contact of a human body with respect to the heater body based on a change in electrostatic capacitance.

[0005] Prior art literature

[0006] Patent Literature

[0007] Patent Document 1: Japanese Patent No. 5954235

[0008] The heater main body of the heater device of Patent Document 1 is formed in a thin plate shape. Therefore, in the heater device of Patent Document 1, when the heater main body comes into contact with water, the water is very close to the detection electrode. Therefore, in this case, the electrostatic capacitance detected by the detection electrode changes greatly due to the contact with water, and even if the human body comes into contact with the heater main body, the contact cannot be detected, and thus false detection may occur. The inventors found the above situation as a result of detailed research. Summary of the invention

[0009] In view of the above-mentioned points, an object of the present invention is to provide a heater device capable of suppressing the inability to detect the contact or approach of an object with respect to a heater surface due to the adhesion of water.

[0010] To achieve the above object, according to one aspect of the present invention, a heater device has a heater surface facing one side in one direction and radiates heat from the heater surface, and the heater device comprises:

[0011] a transmitting electrode and a receiving electrode, the transmitting electrode and the receiving electrode being arranged on the other side of the one direction relative to the heater surface; and

[0012] an insulating cover layer, the insulating cover layer covering the transmitting electrode and the receiving electrode on one side of the one direction relative to the transmitting electrode and the receiving electrode,

[0013] The transmitting electrode and the receiving electrode are electrically connected to a contact detection unit, which detects contact or proximity of an object with respect to the heater surface by a change in electrostatic capacitance between the transmitting electrode and the receiving electrode.

[0014] The insulating cover layer includes a first component part and a second component part, the first component part is composed of an insulating object having electrical insulation properties, and the second component part has a smaller relative dielectric constant than the first component part.

[0015] The second component is located between at least one of the transmitting electrode and the receiving electrode and the heater surface.

[0016] In this way, the second component is configured to shield the wire flying out between the transmitting electrode and the receiving electrode. That is, in the case where water adheres to the surface of the heater, the second component generates electrostatic capacitance in series with the water on the heater surface on the wire. Therefore, assuming a comparative example in which the insulating covering layer is simply composed of the above-mentioned insulating object, the second component plays a role in suppressing the increase in the variation range of the electrostatic capacitance between the transmitting electrode and the receiving electrode caused by the adhesion of water to the heater surface, compared with the comparative example. Therefore, compared with the above-mentioned comparative example, it is possible to suppress the contact or approach of the undetectable object with respect to the heater surface caused by the adhesion of water.

[0017] In addition, the reference symbols in parentheses attached to each component etc. represent an example of the correspondence relationship between the component etc. and the specific components etc. described in the embodiment described later. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 This is a diagram showing a state where the heater device is mounted on a vehicle in the first embodiment.

[0019] Figure 2 This is a cross-sectional view showing a cross section of a part of the heater device cut along a plane along the thickness direction of the heater device in the first embodiment.

[0020] Figure 3 is a schematic diagram showing the first embodiment when viewed from a direction opposite to the heater surface of the heater device (in short, from Figure 2 Diagram of the respective configurations of the heating portion, the transmitting electrode, and the receiving electrode when viewed in the direction indicated by the arrow III.

[0021] Figure 4 A circuit diagram including the heater device, the detection circuit, and the control device in the first embodiment.

[0022] Figure 5 is with Figure 2The figure schematically shows a cross section of a single insulating cover layer included in the heater device according to the first embodiment in the same drawing direction.

[0023] Figure 6 is equivalent to Figure 2 The cross-sectional view schematically shows a state in which water is attached to the heater surface of the heater device of the first comparative example.

[0024] Figure 7 It means in Figure 6 FIG. 1 is a schematic diagram showing electrostatic capacitance generated between the transmitting electrode and the receiving electrode in the heater device of the first comparative example in a state where water is attached.

[0025] Figure 8 is Figure 2 The cross-sectional view schematically shows a state in which water is attached to the heater surface of the heater device of the first embodiment, which is similar to Figure 6 Comparison chart.

[0026] Fig. 9 It means in Figure 8 The schematic diagram of the electrostatic capacitance generated between the transmitting electrode and the receiving electrode in the heater device of the first embodiment in the state where water is attached is shown. Figure 7 Comparison chart.

[0027] Fig.10 This is a timing chart showing sensor values ​​on the vertical axis in the first comparative example, and is a timing chart in a case where water adheres to a certain water adhesion site on the heater surface and then the occupant touches a contact site different from the water adhesion site.

[0028] Fig.11 In the first embodiment, Fig.10 A corresponding timing chart is a timing chart for a case where water adheres to a certain water adhesion site on the heater surface and then the occupant touches a contact site different from the water adhesion site.

[0029] Fig.12 is a cross-sectional view showing a cross section of a portion of the heater device cut by a plane along the thickness direction of the heater device in the second embodiment, which is equivalent to Figure 2 .

[0030] Fig.13 is a cross-sectional view showing a cross section of a portion of the heater device cut along a plane along the thickness direction of the heater device in the second comparative example, which is equivalent to Fig.12 .

[0031] Fig.14is a cross-sectional view showing a cross section of a portion of the heater device cut by a plane along the thickness direction of the heater device in the third embodiment, which is equivalent to Fig.12 .

[0032] Fig.15 is a cross-sectional view showing a cross section of a portion of the heater device cut by a plane along the thickness direction of the heater device in the fourth embodiment, which is equivalent to Figure 2 .

[0033] Fig.16 This is a diagram schematically showing a plurality of ground wires included in an insulating coating layer when viewed from a direction facing a heater surface of a heater device in the fifth embodiment.

[0034] Fig.17 is a circuit diagram including the heater device, the detection circuit and the control device in the fifth embodiment, which is equivalent to Figure 4 .

[0035] Fig.18 is a cross-sectional view showing a cross section of a portion of the heater device cut by a plane along the thickness direction of the heater device in the sixth embodiment, which is equivalent to Figure 2 . DETAILED DESCRIPTION

[0036] Hereinafter, each embodiment will be described with reference to the drawings. In addition, in each of the following embodiments, the same or equivalent parts are denoted by the same reference numerals in the drawings.

[0037] (First Embodiment)

[0038] like Figure 1 As shown, the heater device 10 of this embodiment is installed in the interior of a mobile body such as a vehicle. The heater device 10 constitutes a part of a heating device in the vehicle interior. The heater device 10 is an electric heater that generates heat by receiving power from a power supply device such as a battery or a generator mounted on the mobile body.

[0039] The heater device 10 can be used as a device for heating the occupant 2 immediately after, for example, starting the engine for driving the vehicle. The heater device 10 is configured to radiate radiant heat to the feet of the occupant 2 sitting on the seat 3 in the vehicle interior. For example, the heater device 10 is provided on the lower surface of the steering column cover 6, which is provided to cover the steering column 5 for supporting the steering wheel 4. In addition, the heater device 10 can also be provided on the front panel 7 located below the steering column cover 6.

[0040] like Figure 2 and Figure 3As shown, the heater device 10 is also called a planar heater. The heater device 10 is formed to extend in a planar shape along the XY plane defined by the axis X and the axis Y. In addition, the heater device 10 has a thickness in the direction of the axis Z. That is, the direction of the axis Z is the thickness direction Dt of the heater device 10. In addition, the axis X, the axis Y, and the axis Z are coordinate axes that intersect with each other, and strictly speaking, they are coordinate axes that constitute an orthogonal coordinate system and are orthogonal to each other. In addition, in the description of this embodiment, the thickness direction Dt of the heater device 10 is also referred to as the heater thickness direction Dt as a direction. In addition, Figure 2 Yes means Figure 3 A cross-sectional view of section II-II.

[0041] The heater device 10 of this embodiment is formed in a substantially rectangular thin plate shape. The heater device 10 has a heater surface 10a provided on one side of the heater thickness direction Dt and a heater back surface 10b provided on the other side of the heater thickness direction Dt. The heater surface 10a faces one side of the heater thickness direction Dt, and the heater back surface 10b faces the other side of the heater thickness direction Dt.

[0042] The heater back surface 10b is bonded to the above-mentioned steering column cover 6 or dash panel 7, i.e., the installation object, so that the heater device 10 is fixed to the installation object. On the other hand, the heater device 10 emits radiant heat from the heater surface 10a by being energized. The heater device 10 warms the occupant 2, which is the heating object, located at a position opposite to the heater surface 10a by using this radiant heat.

[0043] The heater device 10 includes an insulating base material 12 , a heat generating portion 20 , a radiation electrode 30 , a reception electrode 40 , an insulating layer 50 , an insulating cover layer 54 , and the like.

[0044] The insulating substrate 12 is formed into a plate shape by a resin material having excellent electrical insulation and high temperature resistance. Specifically, the insulating substrate 12 is formed by a resin film. The insulating substrate 12 has a substrate surface 12a on one side provided in the thickness direction Dt of the heater and a substrate surface on the other side provided in the thickness direction Dt of the heater, that is, a heater back surface 10b.

[0045] The heat generating portion 20 is a heat source in the heater device 10 and is made of a metal material that generates heat when electricity is applied. The heat generating portion 20 is provided on one side (in other words, the passenger side) of the heater thickness direction Dt relative to the insulating substrate 12 and is arranged to contact the substrate surface 12a on one side. Specifically, the heat generating portion 20 is arranged on the substrate surface 12a on one side of the insulating substrate 12 so as to extend in a meandering manner while turning back at a predetermined interval.

[0046] like Figure 4As shown, the heating part 20 is energized by the control device 70. In addition, the control device 7 is composed of a microcomputer including a processor for performing control processing and calculation processing, a storage unit such as ROM and RAM for storing programs and data, and its peripheral circuits. The storage unit is composed of a non-volatile and physical storage medium.

[0047] The control device 70 controls the power supply to the heating portion 20 based on the signal transmitted from the detection circuit 71 and the signal transmitted from the temperature sensor (not shown) provided in the heater device 10. The control device 70 performs on-off control or duty cycle control on the power supply to the heating portion 20 to control the heater device 10 to a specified target temperature. For example, the control device 70 controls the operation of a switch 72 provided in the middle of the wiring connecting the power supply 21, the heating portion 20 and the ground 22, and adjusts the heater device 10 to a specified target temperature. The control device 70, the detection circuit 71, the switch 72 and the heater device 10 constitute the heater system 8 as a whole. In addition, the ground 22 is set as a ground potential point. For example, in the present embodiment, the vehicle body or a portion electrically connected to the vehicle body and having the same potential is equivalent to the ground 22.

[0048] like Figure 2 and Figure 3 As shown in FIG. 1 , the emitting electrode 30 and the receiving electrode 40 are also provided on one side of the heater thickness direction Dt relative to the insulating substrate 12 in the same manner as the heating portion 20, and are arranged to contact the substrate surface 12a on one side. In short, the emitting electrode 30, the receiving electrode 40, and the heating portion 20 are provided on the same layer as each other. In other words, the emitting electrode 30, the receiving electrode 40, and the heating portion 20 are arranged on the substrate surface 12a on one side so as to be arranged in a direction along the substrate surface 12a on the one side.

[0049] The transmitting electrode 30 and the receiving electrode 40 form a pair to detect that an object such as the occupant 2 has contacted or approached the heater surface 10a of the heater device 10. The heater device 10 has a plurality of detection electrode portions 41, which are a combination of the transmitting electrode 30 and the receiving electrode 40 in pairs.

[0050] In each of the plurality of detection electrode portions 41, the paired transmitting electrode 30 and receiving electrode 40 are arranged to be arranged with each other in one direction along the heater surface 10a, that is, in the electrode arrangement direction Dh. Furthermore, as a whole of the heater device 10, the transmitting electrode 30 and the receiving electrode 40 are arranged to be alternately arranged in the electrode arrangement direction Dh. Therefore, the plurality of detection electrode portions 41 are also arranged to be arranged in the electrode arrangement direction Dh. Moreover, the transmitting electrode 30 and the receiving electrode 40 are arranged to be separated from each other.

[0051] Furthermore, the heat generating portion 20 is provided between each of the plurality of detection electrode portions 41 arranged in the electrode arrangement direction Dh.

[0052] When referring to the positional relationship between the heat generating portion 20 , the emitting electrode 30 and the receiving electrode 40 and the heater surface 10 a , the heat generating portion 20 , the emitting electrode 30 and the receiving electrode 40 a are arranged on the other side of the heater surface 10 in the heater thickness direction Dt.

[0053] like Figure 4 As shown, the transmitting electrode 30 and the receiving electrode 40 are electrically connected to the detection circuit 71. When a pulse voltage is applied from the detection circuit 71 to the transmitting electrode 30, an electric field is formed between the transmitting electrode 30 and the receiving electrode 40, and a predetermined charge is accumulated. The detection circuit 71 is configured as a circuit having electrical components such as circuit elements and a microcomputer.

[0054] like Figure 2 As shown in FIG. 1 , when an object such as a finger of the occupant 2 contacts or approaches the heater surface 10a, which is the occupant-side surface of the heater device 10, a portion of the electric wire E representing the charge as an imaginary line is blocked by the object. As a result, the electric field detected by the receiving electrode 40 is reduced by an amount corresponding to the blocking by the object, and the electrostatic capacitance between the transmitting electrode 30 and the receiving electrode 40 is also reduced.

[0055] therefore, Figure 4 The detection circuit 71 captures the change in electrostatic capacitance between the transmitting electrode 30 and the receiving electrode 40, and can detect the contact or approach of an object. In this way, the detection circuit 71 functions as a contact detection unit that detects the contact or approach of an object relative to the heater surface 10a by using the change in electrostatic capacitance between the transmitting electrode 30 and the receiving electrode 40. Moreover, the detection information detected by the detection circuit 71 is transmitted to the control device 70, and the control device 70 controls the power supply to the heating part 20 based on the detection information. In addition, the ground potential of the detection circuit 71 is the same as the ground potential of the ground 22, for example.

[0056] Figure 2 and Figure 3 The emitting electrode 30 and receiving electrode 40 shown are made of metal material and have higher thermal conductivity than the insulating substrate 12, the insulating layer 50 and the insulating cover layer 54. Therefore, the emitting electrode 30 and the receiving electrode 40 are components having a heat dissipation function to diffuse the heat generated by the heat generating portion 20 in the surface direction.

[0057] Furthermore, the transmitting electrode 30 and the receiving electrode 40 are formed in a thin film or a linear shape and have a low heat capacity. Therefore, when the transmitting electrode 30 and the receiving electrode 40 come into contact with an object, the temperature of the contacting portion thereof drops rapidly.

[0058] The insulating layer 50 is a sheet-like material having electrical insulation properties. Figure 2 As shown, the insulating layer 50 is in contact with the heating portion 20, the emitting electrode 30, and the receiving electrode 40, and the insulating layer 50 is provided on one side of the substrate surface 12a to cover the heating portion 20, the emitting electrode 30, and the receiving electrode 40. That is, the insulating layer 50 covers the heating portion 20, the emitting electrode 30, and the receiving electrode 40 on one side of the heater thickness direction Dt relative to the heating portion 20, the emitting electrode 30, and the receiving electrode 40, respectively.

[0059] The insulating layer 50 is made of a material having high insulation properties. As the material constituting the insulating layer 50, for example, resin materials such as polyimide resin, polyurethane resin, acrylic resin, epoxy resin, or silicone resin can be cited, and the insulating layer 50 of this embodiment is made of epoxy resin. In addition, the relative dielectric constant εr of epoxy resin is "εr≈3 to 4", and the relative dielectric constant εr of polyurethane resin is "εr≈6 to 7".

[0060] The insulating cover layer 54 is a sheet-like material having electrical insulation. In addition, the insulating cover layer 54 is the outermost layer on one side of the heater thickness direction Dt in the heater device 10, and therefore, the surface on one side of the insulating cover layer 54 in the heater thickness direction Dt is the heater surface 10a. That is, the heater surface 10a is formed on one side of the insulating cover layer 54 in the heater thickness direction Dt.

[0061] In addition, the insulating cover layer 54 is stacked on the insulating layer 50 on one side in the heater thickness direction Dt, and the insulating cover layer 54 is bonded to the insulating layer 50 by a resin adhesive material or the like. That is, the insulating layer 50 is stacked between the heating portion 20, the emitting electrode 30, and the receiving electrode 40, respectively, and the insulating cover layer 54. Furthermore, although the insulating layer 50 is interposed, the insulating cover layer 54 covers the heating portion 20, the emitting electrode 30, and the receiving electrode 40 on one side in the heater thickness direction Dt relative to the heating portion 20, the emitting electrode 30, and the receiving electrode 40, respectively.

[0062] Specifically, if Figure 5 As shown, the insulating cover layer 54 has a high dielectric constant portion 541 as a first component and a low dielectric constant portion 542 as a second component, and the relative dielectric constant εr of the low dielectric constant portion 542 is smaller than that of the high dielectric constant portion 541. The low dielectric constant portion 542 is formed in the insulating cover layer 54 so as to be divided into a plurality of portions and evenly dispersed. In addition, the high dielectric constant portion 541 is composed of an insulating object 541a having electrical insulation.

[0063] Specifically, the insulating cover layer 54 of this embodiment is made of foamed resin. Therefore, the insulating body 541a is a resin material in the foamed resin. Furthermore, the low dielectric constant portion 542 is made of air contained in the foamed resin as a plurality of bubbles. Figure 2 and Figure 5 As shown, low dielectric constant portion 542 is located between each of transmitting electrode 30 and receiving electrode 40 and heater surface 10a. In addition, since insulating layer 50 is made of resin, relative dielectric constant εr of low dielectric constant portion 542 is smaller than relative dielectric constant εr of insulating layer 50.

[0064] In addition, the material of the resin material of the insulating cover layer 54 , that is, the material of the insulating body 541 a , may be the same as that of the insulating layer 50 , or may be different from that of the insulating layer 50 .

[0065] The insulating layer 50 is different from the insulating cover layer 54 and is not made of a foamed resin. Therefore, the insulating layer 50 does not have the low dielectric constant portion 542. As a general expression, the volume ratio of the constituent of the low dielectric constant portion 542 in the insulating layer 50 is smaller than the volume ratio of the constituent of the low dielectric constant portion 542 in the insulating cover layer 54. The constituent of the low dielectric constant portion 542 is a constituent constituting the low dielectric constant portion 542, and therefore, is air in this embodiment.

[0066] Next, the control device 70 is controlled based on the Figure 4 A control process of controlling the energization of the heating unit 20 using the detection information of the detection circuit 71 shown will be described.

[0067] When the power of the heater device 10 is turned on, the control device 70 energizes the heat generating portion 20 . At the same time, the detection circuit 71 applies a predetermined voltage to the emitter electrode 30 .

[0068] Then, the control device 70 periodically determines, for example, whether the detection circuit 71 detects the approach or contact of an object such as the occupant 2. If the result of the determination is that the detection circuit 71 does not detect the approach or contact of the object, the control device 70 maintains a normal state in which the heating portion 20 is energized with a predetermined current for heating by the heater device 10.

[0069] On the other hand, when the detection circuit 71 detects the approach or contact of an object, the control device 70 sets the magnitude of the current supplied to the heating portion 20 to be lower than the normal state, or stops supplying power to the heating portion 20. Thus, when the object contacts the heater surface 10a of the heater device 10, the temperature of the contacted portion drops rapidly. Therefore, the heater device 10 of this embodiment is highly safe.

[0070] Next, a first comparative example for explaining the effects of the heater device 10 of the present embodiment having the insulating cover layer 54 will be described. Figure 6 As shown, the heater device 80 of the first comparative example does not include the insulating cover layer 54, and the surface of one side of the insulating layer 50 in the heater thickness direction Dt serves as the heater surface 10a. Except for this point, the heater device 80 of the first comparative example is the same as the heater device 10 of the present embodiment.

[0071] like Figure 6 and Figure 7 As shown, in the heater device 80 of the first comparative example, when water WT as water droplets adheres to the heater surface 10a, the insulating layer 50 generates an electrostatic capacitance C1 on the first electric wire E1 passing through the insulating layer 50. In addition, the water WT generates an electrostatic capacitance C2 on the second electric wire E2 passing through the water WT.

[0072] In this case, the relationship between the electrostatic capacitance C1 of the insulating layer 50 and the electrostatic capacitance C2 of the water WT is expressed by the following formula F1.

[0073] C2=(80 / 3)×C1…(F1)

[0074] In addition, the above formula F1 is derived under the condition that εr1, which is the relative dielectric constant εr of the insulating layer 50, is "εr1=about 3", and εr2, which is the relative dielectric constant εr of the water WT, is "εr2=about 80". In addition, the above formula F1 is derived from the relationship that the electrostatic capacitance C is proportional to the dielectric constant ε in the general formula "C=ε×S / d" representing the electrostatic capacitance C when a dielectric with a thickness of d and a dielectric constant ε enters between parallel plates of an electrode area S, and "ε=εr×ε0". In this formula "ε=εr×ε0", ε is the dielectric constant of the dielectric, εr is the relative dielectric constant of the dielectric, and ε0 is the vacuum dielectric constant.

[0075] Moreover, the synthetic electrostatic capacitance C0cw generated between the transmitting electrode 30 and the receiving electrode 40 when water WT adheres to the heater surface 10a in the heater device 80 of the first comparative example (i.e., the synthetic electrostatic capacitance C0cw when water adheres) is expressed by the following formula F2 derived based on the above formula F1.

[0076] C0cw=C1+C2=(83 / 3)×C1…(F2)

[0077] On the other hand, the combined electrostatic capacitance C0 generated between the transmitting electrode 30 and the receiving electrode 40 when water WT is not attached to the heater surface 10a in the heater device 80 of the first comparative example (ie, the combined electrostatic capacitance C0 when water is not attached) is expressed by the following formula F3.

[0078] C0=C1…(F3)

[0079] By comparing the composite electrostatic capacitances C0cw and C0 when water is attached and when water is not attached, it can be seen that in the heater device 80 of the first comparative example, since water WT is attached to the heater surface 10a, the composite electrostatic capacitance generated between the transmitting electrode 30 and the receiving electrode 40 is greatly increased.

[0080] In contrast, the heater device 10 of the present embodiment includes the insulating cover layer 54 as described above. Figure 8 and Fig. 9 As shown, the water WT generates an electrostatic capacitance C2 on the second electric wire E2 passing through the water WT, and the insulating coating layer 54 also generates an electrostatic capacitance C3 at the front and back portions Pa and Pb sandwiching the water WT. In addition, in this embodiment, similarly to the first comparative example, the insulating layer 50 generates an electrostatic capacitance C1 on the first electric wire E1 passing through the insulating layer 50.

[0081] In this case, the relationship between the electrostatic capacitance C1 of the insulating layer 50 and the electrostatic capacitance C3 of the insulating cover layer 54 is expressed by the following formula F4.

[0082] C3=(1 / 3)×C1…(F4)

[0083] In addition, the above formula F4 is derived under the condition that εr1, which is the relative dielectric constant εr of the insulating layer 50, is "εr1=about 3", and εr3, which is the relative dielectric constant εr of the air constituting the low dielectric constant portion 542 of the insulating cover layer 54, is "εr3=about 1". In addition, similarly to the above formula F1, the above formula F4 is derived from the relationship that the electrostatic capacitance C is proportional to the dielectric constant ε in the general formula "C=ε×S / d", and "ε=εr×ε0".

[0084] The synthetic electrostatic capacitance C0w generated between the transmitting electrode 30 and the receiving electrode 40 when water WT is attached to the heater surface 10a in the heater device 10 of the present embodiment (i.e., the synthetic electrostatic capacitance C0w when water is attached) is expressed by the following formula F5. In addition, the following formula F6 is derived from the following formula F5, the above formula F1, and the above formula F4.

[0085] C0w=C1+1 / (1 / C2+2 / C3)…(F5)

[0086] C0w=(563 / 483)×C1…(F6)

[0087] On the other hand, similarly to the first comparative example, the combined electrostatic capacitance C0 when water is not attached in the heater device 10 of the present embodiment is expressed by the above-mentioned formula F3.

[0088] By comparing the synthetic electrostatic capacitances C0w and C0 when water is attached and when water is not attached, it can be seen that in the heater device 10 of this embodiment, the increase in synthetic electrostatic capacitance caused by the attachment of water WT to the heater surface 10a is significantly suppressed compared to the first comparative example.

[0089] As described above, since the change in electrostatic capacity between the transmitting electrode 30 and the receiving electrode 40 when water WT is attached is greatly different between the first comparative example and the present embodiment, the timing diagram showing the time when water WT is attached is Fig.10 and Fig.11 There are also differences between them.

[0090] Should Fig.10 is a timing chart of the first comparative example, Fig.11 is a timing diagram of this embodiment. Specifically, Fig.10 and Fig.11 The water WT is attached to a certain water attachment site Px on the heater surface 10a (see Figure 3 ), then the occupant 2 contacts a contact point Pth different from the water adhesion point Px (refer to Figure 3 ) is a timing diagram for the case of Fig.10 and Fig.11 The vertical axis represents the sensor value Gs.

[0091] In detail, Fig.10 and Fig.11 In the figures, time t1 indicates the time when water WT adheres to the heater surface 10a, time t2 indicates the time when the occupant 2 contacts the heater surface 10a, and time t3 indicates the time when the occupant 2 leaves the heater surface 10a.

[0092] in addition, Fig.10 and Fig.11 The sensor value Gs shown on the vertical axis is a detection circuit 71 (see Figure 4 ). The larger the electrostatic capacitance (composite electrostatic capacitance) between the transmitting electrode 30 and the receiving electrode 40 is, the smaller the sensor value Gs is. Fig.10 and Fig.11 “0” on the vertical axis does not mean that the electrostatic capacitance between the transmitting electrode 30 and the receiving electrode 40 is 0, but means “sensor value Gs=0”.

[0093] like Fig.10As shown, in the first comparative example, the sensor value Gs drops significantly due to the attachment of water WT at time t1. Therefore, even if the occupant 2 contacts the heater surface 10a at time t2, the sensor value Gs remains below the value before time t1. Therefore, in the first comparative example, when water WT is attached to the heater surface 10a, it is impossible to detect that the occupant 2 contacts the heater surface 10a.

[0094] In this regard, Fig.11 As shown, in the present embodiment, the sensor value Gs slightly decreases due to the attachment of water WT at time t1, but is maintained at approximately the same magnitude as before time t1. Thus, when the occupant 2 contacts the heater surface 10a at time t2, the sensor value Gs increases and has a sufficient difference with respect to the magnitude before time t1. Then, when the occupant 2 leaves the heater surface 10a at time t3, the sensor value Gs returns to approximately the same magnitude as before time t1. Therefore, in the present embodiment, even if water WT is attached to the heater surface 10a, it is possible to detect that the occupant 2 has contacted the heater surface 10a. Moreover, it is possible to detect that the occupant 2 who has contacted the heater surface 10a has left the heater surface 10a.

[0095] As mentioned above, Figure 2 and Figure 5 As shown, according to the present embodiment, the heater device 10 includes an insulating coating layer 54. The insulating coating layer 54 includes a high dielectric constant portion 541 and a low dielectric constant portion 542. The high dielectric constant portion 541 is composed of an insulating object 541a having electrical insulation, and the low dielectric constant portion 542 has a lower relative dielectric constant εr than the high dielectric constant portion 541. The low dielectric constant portion 542 is located between at least one of the transmitting electrode 30 and the receiving electrode 40 and the heater surface 10a.

[0096] Therefore, if Figure 5 and Figure 8 As shown in FIG. 1 , the low dielectric constant portion 542 is configured to block the second electric wire E2 that flies out between the transmitting electrode 30 and the receiving electrode 40. That is, when water WT adheres to the heater surface 10a, the low dielectric constant portion 542 generates electrostatic capacitance in series with the water WT on the heater surface 10a on the second electric wire E2. Therefore, compared with, for example, a device without the insulating cover layer 54 Figure 6 Compared with the first comparative example, the low dielectric constant portion 542 plays a role in suppressing the increase in the variation range of the electrostatic capacitance between the transmitting electrode 30 and the receiving electrode 40 due to the adhesion of water WT to the heater surface 10 a.

[0097] Therefore, if you use Figure 6 to Figure 11As described above, in the present embodiment, compared with the first comparative example, the contact or approach of the undetectable object with respect to the heater surface 10 a due to the adhesion of water WT can be suppressed.

[0098] In addition, according to this embodiment, Figure 2 As shown in FIG. 1 , the heater device 10 includes an insulating layer 50 which is stacked between the insulating cover layer 54 and each of the transmitting electrode 30 and the receiving electrode 40 and has electrical insulation. In addition, the volume ratio of the components of the low dielectric constant portion 542 in the insulating layer 50 is smaller than the volume ratio of the components of the low dielectric constant portion 542 in the insulating cover layer 54.

[0099] Therefore, the insulating layer 50 can more easily ensure electrical insulation between the heat generating portion 20, the transmitting electrode 30, and the receiving electrode 40 than the insulating cover layer 54. Furthermore, if the electrical insulation between the heat generating portion 20, the transmitting electrode 30, and the receiving electrode 40 is sufficiently ensured by the insulating layer 50, it is not necessary to require high insulation properties for the insulating cover layer 54. Therefore, compared with the case where there is no insulating layer 50, it is easy to improve the function of the insulating cover layer 54 to reduce the influence of water adhesion.

[0100] In addition, according to this embodiment, Figure 2 and Figure 5 As shown, the low dielectric constant portion 542 included in the insulating cover layer 54 is composed of air. Therefore, the relative dielectric constant εr of the low dielectric constant portion 542 can be reduced by a simple structure. Moreover, the relative dielectric constant εr of air is "εr≈1", and theoretically, the relative dielectric constant εr of air is the smallest, so it can be expected that the effect of maximally suppressing the change in electrostatic capacitance between the transmitting electrode 30 and the receiving electrode 40 caused by the attachment of water WT can be expected.

[0101] In addition, according to the present embodiment, the insulating cover layer 54 is made of a foamed resin, and the insulating object 541a constituting the high dielectric constant portion 541 in the insulating cover layer 54 is a resin material in the foamed resin. Furthermore, the low dielectric constant portion 542 in the insulating cover layer 54 is made of air contained as bubbles in the foamed resin. Therefore, the insulating cover layer 54 can be made into a simple structure, and the relative dielectric constant εr of the low dielectric constant portion 542 can be reduced.

[0102] Furthermore, although the air itself has a heat insulating effect, the insulating object 541a, which is a resin material in the foamed resin, plays a role in transferring the heat generated in the heater device 10 (specifically, the heat generated by the heat generating portion 20) to the heater surface 10a. That is, the heater surface 10a is connected to the heat generating portion 20 in a heat-conductive manner through an object other than the air (specifically, the insulating object 541a and the insulating layer 50). As a result, in the heater device 10, heat can be well transferred via the insulating cover layer 54. Therefore, the low dielectric constant portion 542 can be formed by air without significantly deteriorating the heat dissipation performance of the heater device 10.

[0103] Furthermore, the insulating cover layer 54 can be provided so that the insulating cover layer 54 does not significantly deteriorate the temperature lowering performance of rapidly lowering the temperature of the heater surface 10 a when the occupant 2 comes into contact with the heater surface 10 a .

[0104] (Second Embodiment)

[0105] Next, the second embodiment is described. In this embodiment, the differences from the first embodiment are mainly described. In addition, the description of the same or equivalent parts as the above embodiment is omitted or simplified. This is also the same in the description of the embodiments described later.

[0106] like Fig.12 As shown in FIG. 1 , the heater device 10 of the present embodiment includes a design layer 56 in addition to the structure of the heater device 10 of the first embodiment. In this point, the present embodiment is different from the first embodiment.

[0107] Specifically, the design layer 56 of the heater device 10 of the present embodiment is composed of a sheet-shaped design component having design properties. For example, the design component is fabric, cloth, or leather used for the interior of a vehicle.

[0108] In addition, the design layer 56 is stacked on one side of the insulating cover layer 54 in the heater thickness direction Dt, and the design layer 56 is bonded to the insulating cover layer 54 by, for example, bonding. The design layer 56 is the outermost layer on one side of the heater thickness direction Dt in the heater device 10, and therefore, the surface of the design layer 56 on one side in the heater thickness direction Dt is the heater surface 10a. For example, the design layer 56 is stacked on the insulating cover layer 54 so as to cover the insulating cover layer 54 over the entire insulating cover layer 54.

[0109] In the present embodiment, the heater surface 10a is not formed on the insulating cover layer 54. However, referring to the positional relationship between the insulating cover layer 54 and the heater surface 10a, it can be said that the heater surface 10a is formed on one side of the insulating cover layer 54 in the heater thickness direction Dt.

[0110] Since the design layer 56 is provided in this manner, the appearance of the heater device 10 in the installed state, for example, in the vehicle interior can be improved, in other words, the design of the heater device 10 can be improved.

[0111] In addition, since the heater surface 10 a is formed on the design layer 56 rather than on the insulating cover layer 54 , there is also an advantage that no design requirements are required for the insulating cover layer 54 .

[0112] Here, use Fig.13 A second comparative example for comparison with the present embodiment is described. Fig.13 As shown, the heater device 82 of the second comparative example includes an insulating covering layer 83 which is different from the insulating covering layer 54 of the present embodiment. The insulating covering layer 83 of the second comparative example has a high dielectric constant portion 541 and a low dielectric constant portion 542 similarly to the insulating covering layer 54 of the present embodiment. However, in the insulating covering layer 83 of the second comparative example, the high dielectric constant portion 541 is constituted by a plurality of pads arranged between the insulating layer 50 and the design layer 56, and the air layer formed by the pads is formed as the low dielectric constant portion 542. That is, most of the insulating covering layer 83 of the second comparative example is occupied by the low dielectric constant portion 542 which is the air layer. Except for this point, the heater device 82 of the second comparative example is the same as the heater device 10 of the present embodiment.

[0113] In the heater device 82 of the second comparative example, the thermal conductivity λ of air is “λ≈0.02 W / mK”. Since the thermal conductivity λ of air is relatively small, the low dielectric constant portion 542 as an air layer significantly hinders heat transfer from the heat generating portion 20 to the heater surface 10 a.

[0114] In this regard, in the heater device 10 of the present embodiment, the insulating cover layer 54 is made of a foamed resin, and the low dielectric constant portion 542 is made of air contained as bubbles in the foamed resin, as in the first embodiment. Therefore, compared with the second comparative example, the heat insulation effect of the low dielectric constant portion 542 of the present embodiment is suppressed to be smaller. In addition, by integrally bonding the design layer 56 to the insulating cover layer 54, heat is appropriately transferred from the heat generating portion 20 to the heater surface 10a, and the temperature of the design layer 56 can be easily increased, and radiant heat can be radiated from the heater surface 10a.

[0115] Except for the above-described contents, this embodiment is the same as the first embodiment. Also, in this embodiment, the effects achieved by the common structure with the first embodiment described above can be obtained in the same manner as the first embodiment.

[0116] (Third Embodiment)

[0117] Next, a third embodiment will be described. In this embodiment, points different from the above-described second embodiment will be mainly described.

[0118] like Fig.14 As shown, in this embodiment, the structure of the insulating cover layer 54 is different from that of the second embodiment.

[0119] Specifically, the insulating cover layer 54 of this embodiment is composed of a perforated resin film. Therefore, the insulating object 541a constituting the high dielectric constant portion 541 is the resin material constituting the resin film. Moreover, the low dielectric constant portion 542 is composed of air formed in a plurality of film holes 542a formed in the resin film.

[0120] For example, the plurality of film holes 542a penetrate the insulating cover layer 54 in the heater thickness direction Dt. Furthermore, the plurality of film holes 542a are arranged to be uniformly dispersed along the insulating cover layer 54. Therefore, in this embodiment, the low dielectric constant portion 542 is also arranged to be uniformly dispersed in the insulating cover layer 54.

[0121] Since the insulating cover layer 54 of the present embodiment is as described above, the distribution of the low dielectric constant portion 542 can be arbitrarily set according to the positions of the holes in the resin film constituting the insulating cover layer 54 .

[0122] Therefore, compared with the case where the insulating cover layer 54 is made of, for example, a foamed resin, the following advantages are provided: That is, it is easy to set the distribution of the low dielectric constant portion 542 so that the low dielectric constant portion 542 as air is unlikely to hinder heat transfer from the heat generating portion 20 to the heater surface 10a, and the change in electrostatic capacitance between the electrodes 30 and 40 caused by water adhesion to the low dielectric constant portion 542 is effectively suppressed.

[0123] Except for the above-described contents, this embodiment is the same as the second embodiment. Also, in this embodiment, similarly to the second embodiment, the effects achieved by the configuration common to the second embodiment described above can be obtained.

[0124] In addition, although the present embodiment is a modified example based on the second embodiment, the present embodiment can also be combined with the above-mentioned first embodiment.

[0125] (Fourth Embodiment)

[0126] Next, a fourth embodiment will be described. In this embodiment, points different from the first embodiment described above will be mainly described.

[0127] like Fig.15As shown in FIG. 1 , the heater device 10 of the present embodiment includes a waterproof layer 58 in addition to the structure of the heater device 10 of the first embodiment. In this point, the present embodiment is different from the first embodiment.

[0128] Specifically, the waterproof layer 58 of the heater device 10 of this embodiment is stacked on one side of the insulating cover layer 54 in the heater thickness direction Dt and is bonded to the insulating cover layer 54. The waterproof layer 58 prevents water WT from penetrating into the insulating cover layer 54 from the heater surface 10a.

[0129] For example, the waterproof layer 58 has waterproof and moisture-proof properties. The waterproof layer 58 may be, for example, a moisture-proof sheet bonded to the insulating cover layer 54, or a moisture-proof coating applied on the insulating cover layer 54 and cured.

[0130] The waterproof layer 58 is the outermost layer on one side of the heater thickness direction Dt in the heater device 10, and therefore the surface of the waterproof layer 58 on one side in the heater thickness direction Dt is the heater surface 10a. For example, the waterproof layer 58 is laminated on the insulating cover layer 54 so as to cover the insulating cover layer 54 over the entire insulating cover layer 54.

[0131] Since the waterproof layer 58 is provided in this way, even if the insulating cover layer 54 does not have waterproof and moisture-proof properties, it is possible to prevent water WT from penetrating from the heater surface 10a into the insulating cover layer 54 which is a foamed resin. As a result, the insulating cover layer 54 can always exert the effect of suppressing the increase of the electrostatic capacitance between the transmitting electrode 30 and the receiving electrode 40 due to the adhesion of water WT to the heater surface 10a.

[0132] Except for the above-described contents, this embodiment is the same as the first embodiment. Also, in this embodiment, the effects achieved by the common structure with the first embodiment described above can be obtained in the same manner as the first embodiment.

[0133] In addition, although the present embodiment is a modification example based on the first embodiment, the present embodiment can also be combined with the second embodiment or the third embodiment described above.

[0134] (Fifth Embodiment)

[0135] Next, a fifth embodiment will be described. In this embodiment, points different from the first embodiment described above will be mainly described.

[0136] In this embodiment, the insulating cover layer 54 is also made of a foamed resin as in the first embodiment. Fig.16 and Fig.17As shown, the insulating cover layer 54 of this embodiment has a plurality of grounding wires 543 .

[0137] Specifically, the plurality of grounding wires 543 are connected to each other so as to have the same potential, and are electrically connected to the ground 22. Thus, the plurality of grounding wires 543 and the ground potential of the detection circuit 71 become the same potential.

[0138] For example, the plurality of ground wires 543 are arranged in a lattice pattern in the insulating cover layer 54. Therefore, the plurality of ground wires 543 in a lattice pattern are repeatedly arranged on one side of the transmitting electrode 30 and the receiving electrode 40 in the heater thickness direction Dt.

[0139] Furthermore, the plurality of grounding wires 543 are configured to be distributed at a predetermined density (i.e., a predetermined grounding wire density) inside the insulating cover layer 54. Here, the denser the plurality of grounding wires 543 are distributed, the more effective it is to suppress the increase in electrostatic capacitance between the electrodes 30 and 40 due to water adhesion, but the function of detecting the contact or approach of an object based on the change in electrostatic capacitance between the electrodes 30 and 40 (in other words, the sensitivity) is reduced. Therefore, the density of the grounding wires is determined in advance through experiments so that the function of detecting the contact or approach of an object can be actually obtained, and the effect of suppressing the increase in electrostatic capacitance between the electrodes 30 and 40 due to water adhesion can be obtained.

[0140] Since the plurality of ground wires 543 are provided, the wires E (see Figure 2 ) and the water WT attached to the heater surface 10a are suppressed by the ground line 543. As a result, the increase in electrostatic capacitance between the electrodes 30 and 40 caused by the attachment of water can be suppressed.

[0141] Except for the above-described contents, this embodiment is the same as the first embodiment. Also, in this embodiment, the effects achieved by the common structure with the first embodiment described above can be obtained in the same manner as the first embodiment.

[0142] In addition, although the present embodiment is a modification example based on the first embodiment, the present embodiment can be combined with any of the second to fourth embodiments described above.

[0143] (Sixth Embodiment)

[0144] Next, a sixth embodiment will be described. In this embodiment, points different from the first embodiment described above will be mainly described.

[0145] like Fig.18 As shown, the heater device 10 of this embodiment does not include the insulating layer 50 (see Figure 2). Therefore, the insulating cover layer 54 of this embodiment is provided to be in contact with the heat generating portion 20, the emitting electrode 30 and the receiving electrode 40, and covers the heat generating portion 20, the emitting electrode 30 and the receiving electrode 40 on one side substrate surface 12a.

[0146] Except for the above-described contents, this embodiment is the same as the first embodiment. Also, in this embodiment, the effects achieved by the common structure with the first embodiment described above can be obtained in the same manner as the first embodiment.

[0147] In addition, although the present embodiment is a modification example based on the first embodiment, the present embodiment can be combined with any of the second to fifth embodiments described above.

[0148] (Other Embodiments)

[0149] (1) In the above embodiments, the heat generating portion 20 is arranged on the surface of the insulating base material 12 so as to be folded at predetermined intervals. However, the arrangement method of the heat generating portion 20 is not limited thereto. The heat generating portion 20 can be arranged in various ways.

[0150] (2) In the first embodiment described above, if Figure 2 As shown, the insulating cover layer 54 is stacked on the insulating layer 50 and bonded to the insulating layer 50 by a resin adhesive or the like, but the bonding method is not limited thereto. For example, the insulating cover layer 54 may be welded to the insulating layer 50 .

[0151] (3) In each of the above embodiments, if Figure 2 and Figure 5 As shown in FIG. 1 , the low dielectric constant portion 542 included in the insulating cover layer 54 is located between each of the transmitting electrode 30 and the receiving electrode 40 and the heater surface 10a, but this is an example. Although such a configuration is preferred, it is also conceivable that, for example, the low dielectric constant portion 542 is located between one of the transmitting electrode 30 and the receiving electrode 40 and the heater surface 10a but not between the other and the heater surface 10a. In short, the low dielectric constant portion 542 may be located between at least one of the transmitting electrode 30 and the receiving electrode 40 and the heater surface 10a.

[0152] (4) In the first embodiment described above, if Figure 2 and Figure 5As shown in FIG. 1 , the low dielectric constant portion 542 is composed of air, but this is an example. The low dielectric constant portion 542 may be composed of a component having a smaller relative dielectric constant εr than the insulating object 541a of the high dielectric constant portion 541, and may be composed of a component other than air. This is because the component having a smaller relative dielectric constant εr than the insulating object 541a of the high dielectric constant portion 541 is configured to shield the second electric wire E2 (see FIG. 1 ) that flies out between the transmitting electrode 30 and the receiving electrode 40. Figure 8 ).

[0153] (5) The insulating covering layer 54 of the heater device 10 of the second embodiment described above is made of a foamed resin in the same manner as in the first embodiment, but the insulating covering layer 54 itself may have the function of joining the design layer 56 and the insulating layer 50. That is, in the second embodiment, the insulating covering layer 54 may also be made of a foamed adhesive material containing air as bubbles. In this case, the insulating object 541a of the high dielectric constant portion 541 is a resin material in the foamed adhesive material, and the low dielectric constant portion 542 is made of air contained in the foamed adhesive material as bubbles. Examples of the resin material constituting the foamed adhesive material include acrylic resin, silicone resin, and the like.

[0154] (6) In the description of the first embodiment, although the structure of the bubbles in the foamed resin constituting the insulating cover layer 54 is not mentioned, the foamed resin may also be a closed bubble structure (in other words, a single bubble structure). In this way, it is possible to prevent water WT from penetrating from the heater surface 10a along the bubbles of the foamed resin into the interior of the insulating cover layer 54, which is the foamed resin. As a result, the insulating cover layer 54 can always play the role of suppressing the increase in the electrostatic capacitance between the transmitting electrode 30 and the receiving electrode 40 due to the adhesion of water WT to the heater surface 10a. In addition, Figure 5 The closed cell structure of the foamed resin is schematically shown.

[0155] (7) In each of the above embodiments, for example, Figure 2 and Figure 5 As shown, the insulating cover layer 54 is made of foamed resin and does not contain a material having a higher thermal conductivity than the insulating object 541a, but this is an example. For example, the insulating cover layer 54 may also be made of a material having a higher thermal conductivity than the insulating object 541a (i.e., a high thermal conductivity material). Furthermore, the high thermal conductivity material is preferably a material having a lower relative dielectric constant εr than the insulating object 541a.

[0156] In this way, the insulating covering layer 54 suppresses the increase in electrostatic capacitance between the electrodes 30 and 40 caused by the adhesion of water to the heater surface 10a, and the heat of the heating part 20 is easily transferred to the heater surface 10a compared to the case where the insulating covering layer 54 does not contain the above-mentioned high thermal conductivity material.

[0157] (8) In each of the above embodiments, for example, Figure 2 As shown in the figure, the emitting electrode 30, the receiving electrode 40 and the heating unit 20 are arranged on the substrate surface 12a on one side so as to be arranged side by side in the direction along the substrate surface 12a on the one side, but this is an example. The emitting electrode 30, the receiving electrode 40 and the heating unit 20 do not need to be arranged on the substrate surface 12a on the one side, and various arrangements thereof can be considered.

[0158] (9) In each of the above embodiments, for example, Figure 2 As shown, the heater device 10 has an insulating substrate 12 on the other side of the heater thickness direction Dt in the heater device 10, but it is also possible to consider that the heater device 10 does not have the insulating substrate 12. For example, it is also possible to consider Figure 1 The heater installation portion of the dash panel 7 where the heater device 10 is installed functions as a substitute for the insulating base material 12 .

[0159] (10) In addition, the present invention is not limited to the above-mentioned embodiments, and can be implemented in various modifications. In addition, the above-mentioned embodiments are not independent of each other, and can be appropriately combined except for the case where it is obvious that they cannot be combined.

[0160] In addition, in each of the above-mentioned embodiments, the elements constituting the embodiments are not necessarily required, except for the cases where they are specifically and clearly indicated as required or the cases where they are considered to be obviously required in principle. In addition, in each of the above-mentioned embodiments, when referring to the number, value, quantity, range, or other numerical values ​​of the constituent elements of the embodiments, they are not limited to the specific number, except for the cases where they are specifically and clearly indicated as required or the cases where they are limited to a specific number in principle.

[0161] In addition, in the above-mentioned embodiments, when referring to the material, shape, positional relationship, etc. of the constituent elements, etc., they are not limited to the material, shape, positional relationship, etc. except for cases where they are specifically indicated and cases where they are limited to specific materials, shapes, positional relationships, etc. in principle.

[0162] (Summarize)

[0163] According to the first viewpoint shown in part or all of the above embodiments, the heater device has a heater surface facing one side in one direction, and radiates heat from the heater surface. The heater device has an insulating covering layer covering the transmitting electrode and the receiving electrode on one side in the above one direction relative to the transmitting electrode and the receiving electrode. The insulating covering layer has a first component and a second component, the first component is composed of an insulating object with electrical insulation, and the relative dielectric constant of the second component is smaller than that of the first component. Moreover, the second component is located between at least one of the transmitting electrode and the receiving electrode and the heater surface.

[0164] In addition, according to the second viewpoint, the heater device includes an insulating layer, which is stacked between the insulating cover layer and the transmitting electrode and the receiving electrode and has electrical insulation. In addition, the volume ratio of the constituent of the second component in the insulating layer is smaller than the volume ratio of the constituent of the second component in the insulating cover layer. Therefore, if the electrical insulation of the transmitting electrode and the receiving electrode is sufficiently ensured by the insulating layer, it is not necessary to require high insulation properties for the insulating cover layer. Therefore, compared with the case where there is no insulating layer, it is easy to improve the function of the insulating cover layer to reduce the influence of water adhesion.

[0165] According to the third aspect, the second component is made of air, so the relative dielectric constant of the second component can be reduced with a simple structure.

[0166] In addition, according to the fourth viewpoint, the insulating cover layer is composed of a foamed resin or a foamed adhesive material, the insulating object is a resin material in the foamed resin or the foamed adhesive material, and the second component is composed of air contained as bubbles in the foamed resin or the foamed adhesive material. Therefore, the insulating cover layer can be made into a simple structure, and the relative dielectric constant of the second component can be reduced. Moreover, although the air itself produces a heat-insulating effect, the resin material in the foamed resin or the foamed adhesive material plays a role in transferring the heat generated in the heater device to the heater surface. That is, it is possible to transfer heat well via the insulating cover layer. Therefore, the second component can be formed by air without significantly deteriorating the heat dissipation performance of the heater device.

[0167] In addition, according to the fifth viewpoint, the insulating covering layer is composed of a perforated resin film, the insulating object is a resin material constituting the resin film, and the second component is composed of air formed in the holes of the resin film. In this way, the distribution of the second component can be arbitrarily set according to the perforation position in the resin film. Therefore, compared with the case where the insulating covering layer is composed of, for example, a foamed resin, it is easy to set the distribution of the second component so that the second component is unlikely to hinder heat transfer to the heater surface and effectively suppress the change in electrostatic capacity caused by water adhesion in the second component.

[0168] According to the sixth aspect, the heater device includes a waterproof layer. The waterproof layer is stacked on one side of the insulating cover layer in the above-mentioned one direction to prevent water from penetrating from the heater surface to the insulating cover layer. Therefore, even if the insulating cover layer does not have waterproof and moisture-proof properties, it is possible to prevent water from penetrating from the heater surface to the insulating cover layer. As a result, the insulating cover layer can always play an effect of achieving the purpose of suppressing the increase of the electrostatic capacitance between the transmitting electrode and the receiving electrode due to the adhesion of water to the heater surface.

[0169] According to the seventh aspect, the insulating cover layer is formed to include a material having a higher thermal conductivity than the insulating object. Therefore, the insulating cover layer suppresses the increase in electrostatic capacitance between the transmitting electrode and the receiving electrode caused by the adhesion of water to the heater surface, and heat is easily transferred from the inside of the heater device to the heater surface compared to the case where the insulating cover layer does not include the material having a higher thermal conductivity.

[0170] According to the eighth aspect, the insulating cover layer includes a grounding wire connected to the ground. Therefore, the grounding wire suppresses the intersection of the wire flying between the transmitting electrode and the receiving electrode with the water adhering to the heater surface, thereby suppressing the increase of the electrostatic capacitance between the transmitting electrode and the receiving electrode caused by the water adhering.

Claims

1. A heater device having a heater surface facing one side in one direction and radiating heat from the heater surface, characterized in that: have: a transmitting electrode and a receiving electrode, the transmitting electrode and the receiving electrode being arranged on the other side of the one direction with respect to the heater surface; and an insulating covering layer, the insulating covering layer covering the transmitting electrode and the receiving electrode on the one side of the one direction relative to the transmitting electrode and the receiving electrode, The transmitting electrode and the receiving electrode are electrically connected to a contact detection unit, and the contact detection unit detects contact or proximity of an object with respect to the heater surface through a change in electrostatic capacitance between the transmitting electrode and the receiving electrode. The insulating cover layer includes a first component part and a second component part, the first component part is composed of an insulating object having electrical insulation properties, and the second component part has a smaller relative dielectric constant than the first component part. The second component is located between at least one of the transmitting electrode and the receiving electrode and the heater surface.

2. The heater device according to claim 1, characterized in that An insulating layer is provided, the insulating layer being stacked between the insulating cover layer and the transmitting electrode and the receiving electrode and having electrical insulation properties, The volume ratio of the component of the second component part in the insulating layer is smaller than the volume ratio of the component of the second component part in the insulating cover layer.

3. The heater device according to claim 1 or 2, characterized in that The second component is composed of air.

4. The heater device according to claim 1 or 2, characterized in that The insulating covering layer is made of foamed resin or foamed adhesive material. The insulating object is the resin material in the foamed resin or the foamed adhesive material, The second component portion is composed of air contained as bubbles in the foamed resin or the foamed adhesive material.

5. The heater device according to claim 1 or 2, characterized in that: The insulating cover layer is composed of a perforated resin film, The insulating object is a resin material constituting the resin film, The second constituent part is composed of air formed in the pores of the resin film.

6. The heater device according to claim 1 or 2, characterized in that: A waterproof layer is provided, which is laminated on the one side of the insulating cover layer in the one direction and prevents water from penetrating from the surface of the heater to the insulating cover layer.

7. The heater device according to claim 1 or 2, characterized in that The insulating cover layer is configured to include a material having a higher thermal conductivity than the insulating object.

8. The heater device according to claim 1 or 2, characterized in that The insulating cover layer has a grounding line connected to the ground.

9. The heater device according to claim 1 or 2, characterized in that: The second component is configured to shield electric wires protruding between the transmitting electrode and the receiving electrode, the electric wires being lines representing electric charges as virtual lines.

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