Heater device

Abstract

To stably increase the reaction strength of contact detection while suppressing thermal discomfort.SOLUTION: A heating wire 20 has a first heating wire 21 and a second heating wire 22. A receiving electrode 40 is provided between the first heating wire 21 and the second heating wire 22. A transmitting electrode 30 has a first transmitting electrode 31 provided between the first heating wire 21 and the receiving electrode 40, and a second transmitting electrode 32 provided between the second heating wire 22 and the receiving electrode 40. The first heating wire 21, the first transmitting electrode 31, the receiving electrode 40, the second transmitting electrode 32, and the second heating wire 22 extend side by side in a predetermined layer of an insulating base material 10 in this order. A distance Dh1 between the first heating wire 21 and the first transmitting electrode 31, a distance Ds1 between the first transmitting electrode 31 and the receiving electrode 40, a distance Dh2 between the second heating wire 22 and the second transmitting electrode 32, and a distance Ds2 between the second transmitting electrode 32 and the receiving electrode 40 has a relation of Dh1≤Ds1 and Dh2≤Ds2.SELECTED DRAWING: Figure 4

Description

Technical Field

[0001] The present invention relates to a heater device that radiates radiant heat to warm an object.

Background Art

[0002] Conventionally, a heater device mounted on a vehicle and radiating radiant heat to warm a passenger is known. The heater device described in Patent Document 1 has a heating wire folded back at a predetermined interval in a predetermined layer of an insulating base material, and a transmitting electrode and a receiving electrode for object contact detection are arranged between adjacent heating wires. Thereby, this heater device constitutes a planar heater that enables single-sided substrate formation while achieving a good in-plane temperature distribution.

[0003] When the heating wire of this heater device is energized, the heating wire generates heat and has a function of radiating radiant heat to the passenger. Further, this heater device has a function of reducing the amount of power supplied to the heating wire to be lower than the normal state or stopping the power supply when it is detected that an object such as a passenger's finger has come into contact with or approached due to a change in the capacitance of a capacitor formed by the transmitting electrode and the receiving electrode. Thereby, this heater device suppresses an increase in the temperature of an object that touches the passenger-side surface and prevents the occurrence of thermal discomfort in the passenger or the like. In the following description, the capacitance of the capacitor formed by the transmitting electrode and the receiving electrode is referred to as "capacitor capacitance C".

Prior Art Documents

Patent Documents

[0004]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0005] However, in the heater device described in Patent Document 1, a heating wire, a transmitting electrode, a receiving electrode, and a heating wire are arranged in this order on a predetermined layer of an insulating base material. That is, one heating wire and the transmitting electrode are arranged adjacent to each other, and the other heating wire and the receiving electrode are arranged adjacent to each other. Therefore, when the control unit performs on-off control or duty control of energization to the heating wire so as to set the temperature of the heater device to a predetermined temperature, there is a problem that the noise of contact detection increases due to large fluctuations in the current and voltage flowing through the heating wire, which causes a large fluctuation in the capacitor capacitance C.

[0006] Further, in the heater device described in Patent Document 1, a plurality of wide portions are provided at predetermined intervals over the entire receiving electrode, and a plurality of branch wirings are provided at predetermined intervals over the entire transmitting electrode. Therefore, there is also a problem that the capacitor capacitance C becomes large and the reaction intensity of contact detection becomes weak. In addition, since the heater device described in Patent Document 1 has a configuration in which the occupancy rate per unit area of the conductive material provided on the insulating base material is relatively large, there is also a concern that a thermal discomfort may occur when an object such as a passenger's finger comes into contact. Thus, there is room for further improvement in the heater device described in Patent Document 1 in view of suppressing the thermal discomfort when an object comes into contact.

[0007] In view of the above points, an object of the present invention is to provide a heater device that can suppress thermal discomfort when an object comes into contact and make the reaction intensity of contact detection more stably strong.

Means for Solving the Problems

[0008] To achieve the above object, according to the invention described in claim 1, the heater device includes an insulating base material (10), a heating wire (20), a receiving electrode (40), a transmitting electrode (30), and a control unit (80). The heating wire has a first heating wire (21) and a second heating wire (22), and generates heat when energized. The receiving electrode is provided between the first heating wire and the second heating wire. The transmitting electrode has a first transmitting electrode (31) provided between the first heating wire and the receiving electrode, and a second transmitting electrode (32) provided between the second heating wire and the receiving electrode. The control unit controls the energization of the heating wire so that the temperature of the region where the heating wire is disposed on the insulating base material becomes a predetermined temperature, and when the contact or proximity of an object is detected due to a change in the capacitance between the transmitting electrode and the receiving electrode, the amount of energization of the heating wire is made lower than the normal state or the energization is stopped. Here, the first heating wire, the first transmitting electrode, the receiving electrode, the second transmitting electrode, and the second heating wire are provided so as to extend side by side in this order in a predetermined layer of the insulating base material. And, let the distance between the first heating wire and the first transmitting electrode be Dh1, the distance between the first transmitting electrode and Subject to the distance between the transmitting electrode be Ds1, the distance between the second heating wire and the second transmitting electrode be Dh2, and the distance between the second transmitting electrode and Subject to the transmitting electrode be Ds2, then the relationship Dh1≤Ds1 and Dh2≤Ds2 is satisfied.

[0009] Generally, in capacitance-type contact detection, the larger the ratio of the capacitance change (hereinafter referred to as "change capacitance ΔC") that occurs when an object such as a user's finger contacts or approaches with respect to the capacitance of the capacitor formed by the transmitting electrode and the receiving electrode (hereinafter referred to as "capacitor capacitance C"), the stronger the reaction intensity. That is, the reaction intensity is in the relationship of reaction intensity ∝ΔC / C.

[0010] In the above formula, the capacitor capacitance C is represented by a predetermined function of the value obtained by multiplying the shape characteristics of the electrodes and the electrode length. That is, it is in the relationship of C = f(shape characteristics × electrode length). On the other hand, the change capacitance ΔC is represented by a predetermined function of the shape characteristics of the electrodes. That is, it is in the relationship of ΔC = f(shape characteristics).

[0011] Also, in the above formula, regarding the shape characteristics of the parallel plate capacitor, when the area of the parallel plates is S, the permittivity between the parallel plates is ε, and the distance between the parallel plates is Ds, it has a relationship of C = εS / Ds. Note that when the transmitting electrode and the receiving electrode are arranged in a predetermined layer of the insulating substrate as in the invention according to Claim 1 above, the area of the surfaces facing each other in the transmitting electrode and the receiving electrode (that is, the thickness surface of the electrode with the surface direction of the insulating substrate as the normal) is the area S of the parallel plates. Also, the distance Ds between the transmitting electrode and the receiving electrode is the distance Ds between the parallel plates.

[0012] On the other hand, between the transmitting electrode and the receiving electrode, in addition to the direction in which the transmitting electrode and the receiving electrode face each other (that is, the surface direction of the insulating substrate), electric lines of force are formed in a parabolic shape in the direction perpendicular to the surface of the insulating substrate (hereinafter referred to as the "Z direction"). When an object comes into contact or close to the transmitting electrode and the receiving electrode via a skin material or the like, the capacitance change ΔC is likely to reflect the influence of the electric lines of force in the Z direction. Furthermore, although the system becomes complicated when taking into account the heat flow related to the temperature distribution, the inventors have found an effective shape through continuous intensive research.

[0013] In the heater device described in Patent Document 1 cited as the above prior art document, the first heating wire, the transmitting electrode, the receiving electrode, and the second heating wire were arranged in this order in a predetermined layer of the insulating substrate. In this arrangement, when the control unit controls the energization of the heating wire, due to the fluctuations in the current and voltage flowing through the first heating wire and the second heating wire, there is a problem that the noise of contact detection increases because the capacitance C of the capacitor formed by the transmitting electrode and the receiving electrode fluctuates greatly.

[0014] In contrast, in the invention according to Claim 1, the heater device is configured such that in a predetermined layer of the insulating substrate, the receiving electrode is sandwiched between the first transmitting electrode and the second transmitting electrode, and the first heating wire and the second heating wire are arranged outside thereof. Thereby, when the control unit controls the energization of the heating wire, even if there are fluctuations in the current and voltage flowing through the heating wire, the fluctuations in the capacitance C of the capacitor formed by the first transmitting electrode and the receiving electrode and the capacitance C of the capacitor formed by the second transmitting electrode and the receiving electrode are reduced, and it becomes possible to suppress the contact detection noise.

[0015] Furthermore, in the invention according to claim 1, the heater device is configured to have the relationship of Dh1 ≤ Ds1 and Dh2 ≤ Ds2. Hereinafter, Dh1 and Dh2 are simply denoted as "Dh", and Ds1 and Ds2 are simply denoted as "Ds". In the arrangement of the wiring described in claim 1, as a result of performing a thermal analysis simulation, the inventors found that the surface average temperature improves as Ds / Dh increases. This is presumably because by reducing the distance Dh between the heating wire and the transmitting electrode, the amount of heat transfer from the high-temperature heating wire to the transmitting electrode increases, and the transmitting electrode diffuses heat to the receiving electrode side, thereby increasing the surface average temperature. Furthermore, the inventors found from the results of this thermal analysis simulation that there is an inflection point near Ds / Dh = 1.

[0016] Also, in the arrangement of the wiring described in claim 1, as a result of performing an electromagnetic field analysis simulation, the inventors found that the reaction intensity improves as Ds / Dh increases. This is presumably because by increasing the distance Ds between the transmitting electrode and the receiving electrode, the capacitance C decreases, and at the same time, the change capacitance ΔC increases due to the increase in the electric field lines in the Z direction, so the reaction intensity improves. Furthermore, the inventors also found from the results of this electromagnetic field analysis simulation that there is an inflection point near Ds / Dh = 1. Based on these simulation results, in the invention according to claim 1, the heater device is configured to have the relationship of Dh ≤ Ds (specifically, Dh1 ≤ Ds1 and Dh2 ≤ Ds2). Thereby, the surface average temperature of the heater device can be improved, and the reaction intensity can be stably enhanced.

[0019] Note that the reference numerals in parentheses attached to each component etc. indicate an example of the correspondence relationship between the component etc. and the specific components etc. described in the embodiments described later.

Brief Description of the Drawings

[0020]

Figure 1

Figure 2

Figure 3

Figure 4

Figure 5

Figure 6

Figure 7

Figure 8

Figure 9

Figure 10

Figure 11

Figure 12

Figure 13

Figure 14

Embodiments for Carrying Out the Invention

[0021] Hereinafter, embodiments of the present invention will be described with reference to the drawings. In the following embodiments, parts that are identical or equivalent to each other are denoted by the same reference numerals, and the description thereof will be omitted. In the following description and in the respective drawings, the terms "upper", "lower", "left", and "right" are used for convenience of explanation and do not limit the usage state of the heater device or the like.

[0022] (First Embodiment) The heater device according to the first embodiment will be described. As shown in FIG. 1, the heater device 1 is installed in the interior of a moving body such as a vehicle. The heater device 1 forms part of the heating device in the vehicle interior. The heater device 1 is an electric heater that is supplied with electric power from a power supply device such as a battery or a generator mounted on the moving body and generates heat. The heater device 1 is a planar heater formed in a thin plate shape having flexibility, and has a heater main body portion 2 that generates heat when electric power is supplied. Then, the heater device 1 mainly radiates radiant heat H in the thickness direction of the heater main body portion 2 and is used to warm an object located in that direction.

[0023] The heater device 1 can be used, for example, as a device for immediately providing warmth to the occupant 3 immediately after starting the engine for vehicle travel. The heater device 1 is installed so as to radiate radiant heat H to the feet of the occupant 3 sitting on the seat 4 in the vehicle interior. For example, the heater device 1 is installed on the lower surface of the steering column cover 7 provided so as to cover the steering column 6 for supporting the steering 5, or on the dashboard 8 located below the steering column cover 7. Since the heater device 1 has flexibility, it is installed along each mounting surface.

[0024] FIG. 2 is a plan view of the heater main body portion 2 of the heater device 1. In this state, the heater device 1 extends along the X - Y plane defined by the axis X and the axis Y. Further, FIG. 3 is a cross - sectional view taken along line III - III of FIG. 2. As shown in FIG. 3, the heater main body portion 2 of the heater device 1 is formed in a thin plate shape having a thickness in the direction of the axis Z.

[0025] As shown in FIGS. 2 and 3, the heater device 1 includes an insulating base material 10, a heating wire 20, a transmitting electrode 30, a receiving electrode 40, an insulating layer 50, a skin material 60, and the like. The insulating base material 10 and the insulating layer 50 are made of a resin material (such as a polyimide film) having excellent electrical insulation properties and being resistant to high temperatures. The heating wire 20, the transmitting electrode 30, and the receiving electrode 40 are provided on the surface of the insulating base material 10 that is disposed on the side opposite to the occupant 3. That is, the heating wire 20, the transmitting electrode 30, and the receiving electrode 40 are provided in the same layer. The insulating layer 50 covers the surface of the insulating base material 10 that is disposed on the side opposite to the occupant 3, the heating wire 20, the transmitting electrode 30, and the receiving electrode 40. On the other hand, the skin material 60 is provided on the surface of the insulating base material 10 that is disposed on the side of the occupant 3.

[0026] Note that FIGS. 2 and 4 are views seen through the insulating layer 50 from the side opposite to the occupant 3 of the insulating base material 10. This is the same for FIGS. 9 to 12 and FIG. 14 referred to in each of the embodiments and comparative examples described later.

[0027] As shown in FIG. 2, the heating wire 20 is arranged to be folded back at a predetermined interval so as to meander in a predetermined layer of the insulating base material 10. The heating wire 20 is made of a metal material that generates heat when energized. The transmitting electrode 30 and the receiving electrode 40 are also made of a metal material capable of being energized.

[0028] Hereinafter, the arrangement of each wiring (that is, the heating wire 20, the transmitting electrode 30, and the receiving electrode 40) illustrated in FIG. 2 will be described. In the following description, for the sake of convenience of explanation, terms such as "upper", "lower", "left", and "right" on the paper surface of the reference figure are used for explanation, but these terms do not limit the state in which the heater device 1 is installed in a vehicle or the like. This is the same for the description of each of the embodiments and comparative examples described later.

[0029] In the arrangement of each wiring illustrated in FIG. 2, the heating wire 20 extends upward from the positive terminal 71 provided on the insulating base material 10 on the paper surface of FIG. 2, extends leftward from its tip P1, extends upward from its tip P2, extends rightward from its tip P3, extends upward from its tip P4, and repeats such a shape multiple times, and is provided so as to meander in the left region of the insulating base material 10. Thereafter, the heating wire 20 extends from the left region of the insulating base material 10 to the right region, extends downward from its tip P5, extends leftward from its tip P6, extends downward from its tip P7, extends rightward from its tip P8, extends downward from its tip P9, and repeats such a shape multiple times. After meandering in the right region of the insulating base material 10, it is connected to the ground terminal 72.

[0030] The transmitting electrode 30 is provided along the heating wire 20 at a certain interval from the heating wire 20. That is, the transmitting electrode 30 and the heating wire 20 are provided in parallel. Specifically, the transmitting electrode 30 is provided so as to meander in the left region of the insulating base material 10 along the heating wire 20 from the first detection terminal 73 provided on the insulating base material 10, and then extends from the left region of the insulating base material 10 to the right region, and is provided so as to meander in the right region of the insulating base material 10 along the heating wire 20.

[0031] The receiving electrode 40 is provided in parallel with the transmitting electrode 30 at a certain interval from the transmitting electrode 30. Specifically, the receiving electrode 40 includes a central wiring 41 that extends upward from the second detection terminal 74 provided on the insulating base material 10, a plurality of left wirings 42 that extend leftward from the middle or tip of the central wiring 41, and a plurality of right wirings 43 that extend rightward from the middle or tip of the central wiring 41. Among the receiving electrodes 40, the central wiring 41 is provided between the wiring provided in the left region of the insulating base material 10 of the transmitting electrode 30 and the wiring provided in the right region of the insulating base material 10 of the transmitting electrode 30. Among the receiving electrodes 40, the left wiring 42 is provided between adjacent wirings that are folded back in the left region of the insulating base material 10 of the receiving electrode 40. Among the receiving electrodes 40, the right wiring 43 is provided between adjacent wirings that are folded back in the right region of the insulating base material 10 of the receiving electrode 40. With such an arrangement, each wiring is provided in the order of the heating wire 20, the transmitting electrode 30, the receiving electrode 40, the transmitting electrode 30, and the heating wire 20 at various locations of the insulating base material 10.

[0032] Note that the arrangement of each wiring shown in FIG. 2 is an example, and the arrangement of each wiring included in the heater device 1 is not limited thereto.

[0033] The plus terminal 71 and the ground terminal 72 provided at both ends of the heating wire 20 are electrically connected to the control unit 80. Therefore, the energization of the heating wire 20 is controlled by the control unit 80. When a current flows through the heating wire 20 due to the energization control by the control unit 80, the heating wire 20 generates heat. Note that the control unit 80 includes a microcomputer including a processor that performs control processing and arithmetic processing, a storage unit such as a ROM and a RAM that stores programs and data, and its peripheral circuits. The storage unit is composed of a non-transitory physical storage medium. The control unit 80 detects the temperature of the region where the heating wire 20 is provided by a temperature sensor (not shown) provided in the region of the insulating base material 10 where the heating wire 20 is provided. Then, in order to control the temperature of the region where the heating wire 20 is provided to a predetermined target temperature, the control unit 80 performs on / off control or duty control of the energization to the heating wire 20.

[0034] Also, the first detection terminal 73 provided at one end of the transmitting electrode 30 and the second detection terminal 74 provided at one end of the receiving electrode 40 are also electrically connected to a detection circuit (not shown) included in the control unit 80. The control unit 80 has a function of detecting that an object including the occupant 3 has come into contact with or approached due to a change in the capacitance (hereinafter referred to as "capacitor capacitance C") stored in the capacitor formed by the transmitting electrode 30 and the receiving electrode 40. Specifically, when a pulsed voltage is applied to the transmitting electrode 30 from the detection circuit included in the control unit 80, an electric field is formed between the transmitting electrode 30 and the receiving electrode 40, and a predetermined charge is accumulated.

[0035] As shown in FIG. 3, when an object such as the finger 9 of the occupant 3 comes into contact with or approaches the occupant-side surface of the heater main body 2, a part of the electric lines of force E that fly in a parabolic shape in the Z direction is blocked by the object. Then, the electric field detected by the receiving electrode 40 decreases by the amount blocked by the object, and the capacitance C of the capacitor formed by the transmitting electrode 30 and the receiving electrode 40 also decreases. Therefore, the detection circuit of the control unit 80 can detect the contact or proximity of the object by capturing the change in the capacitance (hereinafter referred to as "change capacitance ΔC") that changes when the object comes into contact or proximity.

[0036] When the control unit 80 detects the contact or proximity of an object, it reduces the amount of current supplied to the heating wire 20 to a level lower than the normal state or stops the current supply. The heating wire 20, the transmitting electrode 30, and the receiving electrode 40 are all formed linearly and have a low heat capacity. Also, since the heating wire 20, the transmitting electrode 30, and the receiving electrode 40 are all provided in the same layer of the insulating base material 10, the layer configuration of the heater main body 2 is reduced, so the total thickness of the heater main body 2 is reduced and the amount of wiring metal is also reduced. Therefore, in this heater device 1, since the heat capacity of the heater main body 2 is reduced, the function of rapidly lowering the temperature when an object touches it can be improved.

[0037] Also, in the first embodiment, when the area of the heater main body 2 where each wiring (that is, the heating wire 20, the receiving electrode 40, and the transmitting electrode 30) of the insulating base material 10 is provided is Sb, and the total value of the areas of the surfaces that are normal to the thickness direction (that is, the Z direction) of the heater main body 2 in each wiring is Sw, 0.5× Sb ≧S The length and width of each wiring are set so that it becomes w. This makes it possible to reduce the occupancy rate of the conductive material per unit area of the heater main body 2 and prevent the occurrence of thermal discomfort when a user's finger or the like touches the heater main body 2.

[0038] Furthermore, in the heater device 1 of the first embodiment, the wirings are arranged such that the reaction intensity of contact detection becomes stably strong when an object such as a user's finger comes into contact with or approaches the heater main body 2. The arrangement of each wiring in the heater device 1 of this first embodiment will be described in detail with reference to FIG. 4. In FIG. 4, for ease of distinction between the insulating base material 10 and each wiring, although it is not a cross-section, hatching is applied to each wiring. This is the same for FIGS. 9 to 12 and FIG. 14 referred to in the embodiments and comparative examples described later.

[0039] As described above, each wiring included in the heater device 1 is provided side by side in the order of the heating wire 20, the transmitting electrode 30, the receiving electrode 40, the transmitting electrode 30, and the heating wire 20 at various locations on the insulating base material 10. Hereinafter, for convenience of explanation, each wiring shown in FIG. 4 will be referred to as the first heating wire 21, the first transmitting electrode 31, the receiving electrode 40, the second transmitting electrode 32, and the second heating wire 22 from the upper side of the paper surface of FIG. 4.

[0040] The heating wire 20 has the first heating wire 21 and the second heating wire 22. Between the first heating wire 21 and the second heating wire 22, the first transmitting electrode 31, the receiving electrode 40, and the second transmitting electrode 32 are arranged. Thereby, when the control unit 80 controls the energization of the heating wire 20, even if there are fluctuations in the current and voltage flowing through the heating wire 20, the fluctuations in the capacitor capacitance C formed by the first transmitting electrode 31 and the receiving electrode 40, and the capacitor capacitance C formed by the second transmitting electrode 32 and the receiving electrode 40 are reduced, and it is possible to suppress contact detection noise.

[0041] Here, let the distance between the first heating wire 21 and the first transmitting electrode 31 be Dh1, and the distance between the first transmitting electrode 31 and Subject to the receiving electrode 4 0 be Ds1, the distance between the second heating wire 22 and the second transmitting electrode 32 be Dh2, and the distance between the second transmitting electrode 32 and Subject to the receiving electrode 4 0 be Ds2. At this time, each wiring has the relationship of Dh1 ≤ Ds1 and Dh2 ≤ Ds2.

[0042] Also, let the width of the first heating wire 21 be Wh1 and the width of the second heating wire 22 be Wh2. At this time, each wiring has the relationship of Dh1 ≤ Wh1 and Dh2 ≤ Wh2.

[0043] Also, let the width of the first transmitting electrode 31 be Wd1, the width of the second transmitting electrode 32 be Wd2, and the width of the receiving electrode 40 be Wi. At this time, each wiring has the relationship of Wd1 ≤ Wi and Wd2 ≤ Wi. Also, each wiring has the relationship of Wi ≤ Ds1 and Wi ≤ Ds2.

[0044] Hereinafter, the significance of defining the intervals, line widths, and areas of each wiring in this way will be described. First, the significance of Dh1 ≤ Ds1 and Dh2 ≤ Ds2 will be described with reference to the graphs in FIGS. 5 and 6. Hereinafter, Dh1 and Dh2 will be simply denoted as "Dh", and Ds1 and Ds2 will be simply denoted as "Ds".

[0045] The graph in FIG. 5 shows the simulation results of the thermal analysis performed by the inventors regarding the arrangement relationship of each wiring. In this simulation, with the distance between the first heating wire 21 and the second heating wire 22 fixed and the widths of each wiring fixed, Ds / Dh was changed to calculate the surface average temperature of the heater main body 2. From this simulation result, it can be seen that the surface average temperature improves as Ds / Dh increases. This is considered to be because by reducing the distance Dh between the heating wire 20 and the transmitting electrode 30, the amount of heat transfer from the high-temperature heating wire 20 to the transmitting electrode 30 increases, and the transmitting electrode 30 diffuses heat to the receiving electrode 40 side, thereby increasing the surface average temperature. Furthermore, the inventors found from the simulation results of this thermal analysis that there is an inflection point near Ds / Dh = 1. That is, when Ds / Dh is less than 1, the surface average temperature tends to decrease rapidly. Therefore, by setting Ds / Dh to 1 or more (i.e., Dh ≤ Ds), the surface average temperature can be stably improved.

[0046] Further, the graph in FIG. 6 shows the simulation results of the electromagnetic field analysis performed by the inventors regarding the arrangement relationship of each wiring. Also in this simulation, with the distance between the first heating wire 21 and the second heating wire 22 fixed and the width of each wiring fixed, Ds / Dh was changed to calculate the reaction intensity (i.e., ΔC / C). From this simulation result, it can be seen that the reaction intensity improves as Ds / Dh increases. This is considered because increasing the distance Ds between the transmitting electrode 30 and the receiving electrode 40 decreases the capacitance C, and at the same time, the change capacitance ΔC increases due to the increase in the electric field lines in the Z direction, so the reaction intensity improves. Furthermore, the inventors also found from the simulation results of this electromagnetic field analysis that there is an inflection point near Ds / Dh = 1. That is, when Ds / Dh is less than 1, the rate of decrease in the reaction intensity tends to increase. Therefore, by setting Ds / Dh to 1 or more (i.e., Dh ≤ Ds), the reaction intensity can be stably increased.

[0047] Next, the significance of Dh1 ≤ Wh1 and Dh2 ≤ Wh2 will be explained. Hereinafter, Dh1 and Dh2 will be simply referred to as "Dh", and Wh1 and Wh2 will be simply referred to as "Wh". According to this, by making the distance Dh between the heating wire 20 and the transmitting electrode 30 smaller than the width Wh of the heating wire 20 and bringing the transmitting electrode 30 closer to the high-temperature heating wire 20, the amount of heat transfer from the heating wire 20 to the transmitting electrode 30 increases, so the surface average temperature can be improved. Also, with the distance between the first heating wire 21 and the second heating wire 22 fixed, as the distance Dh between the heating wire 20 and the transmitting electrode 30 is decreased, if the distance Ds between the transmitting electrode 30 and the receiving electrode 40 is increased, the reaction intensity can be stably increased.

[0048] Subsequently, the significance of Wd1 ≤ Wi and Wd2 ≤ Wi will be explained. Hereinafter, Wd1 and Wd2 will be simply referred to as "Wd". According to this, since the receiving electrode 40 is arranged to be sandwiched between the first transmitting electrode 31 and the second transmitting electrode 32, by setting Wd ≤ Wi, the capacitance formation of the capacitor formed by the two transmitting electrodes 30 and the one receiving electrode 40 can be stabilized.

[0049] Next, the meaning of Wi ≤ Ds1 and Wi ≤ Ds2 will be described with reference to the graphs of FIGS. 7 and 8. In the following description as well, Ds1 and Ds2 will be simply referred to as "Ds".

[0050] The graph of FIG. 7 shows the simulation results of the surface occupancy analysis of the conductive material conducted by the inventors regarding the arrangement relationship of each wiring. In this simulation, with the distance between the first heating wire 21 and the second heating wire 22 fixed and the width Wh of the heating wire 20 and the width Wd of the transmitting electrode 30 fixed, Ds / Wi was changed to calculate the surface occupancy of the conductive material. From this simulation result, it can be seen that the larger Ds / Wi is, the smaller the occupancy rate of the conductive material in the heater main body 2 becomes. Here, from the viewpoint of suppressing the thermal discomfort when a user's finger or the like touches the heater main body 2, it is advantageous to lower the occupancy rate of the conductive material per unit area of the heater main body 2. Therefore, by increasing the distance Ds between the transmitting electrode 30 and the receiving electrode 40 and decreasing the Wi of the receiving electrode 40, the occupancy rate of the conductive material decreases, so that the thermal discomfort can be suppressed. Furthermore, the inventors found from this simulation result of the surface occupancy analysis of the conductive material that there is an inflection point near Ds / Wi = 1. That is, when Ds / Wi is greater than 1, the occupancy rate of the conductive material tends to increase rapidly. From this, by setting Ds / Wi to 1 or more (that is, Wi ≤ Ds), it is possible to suppress the occurrence of thermal discomfort in the user of the heater device 1.

[0051] In addition, the graph of FIG. 8 shows the simulation results of the electromagnetic field analysis performed by the inventors regarding the arrangement relationship of each wiring. Also in this simulation, with the distance between the first heating wire 21 and the second heating wire 22 fixed, and the width Wh of the heating wire 20 and the width Wd of the transmitting electrode 30 fixed, Ds / Wi was changed to calculate the reaction intensity (i.e., ΔC / C). From these simulation results, it can be seen that the reaction intensity improves as Ds / Wi increases. This is presumably because increasing the distance Ds between the transmitting electrode 30 and the receiving electrode 40 decreases the capacitance C, and at the same time, the change capacitance ΔC increases due to the increase in the electric lines of force in the Z direction, thus improving the reaction intensity. Furthermore, the inventors also found from these simulation results of the electromagnetic field analysis that there is an inflection point near Ds / Wi = 1. That is, when Ds / Wi is less than 1, the rate of decrease in the reaction intensity tends to increase. Therefore, by setting Ds / Wi to 1 or more (i.e., Wi ≦ Ds), the reaction intensity can be stably strengthened.

[0052] The heater device 1 of the first embodiment described above has the following operational effects. (1) In the first embodiment, the heater device 1 is configured such that in a predetermined layer of the insulating base material 10, the receiving electrode 40 is disposed so as to be sandwiched between the first transmitting electrode 31 and the second transmitting electrode 32, and the first heating wire 21 and the second heating wire 22 are disposed outside thereof. According to this, when the control unit 80 controls the energization of the heating wire 20, even if there are fluctuations in the current and voltage flowing through the heating wire 20, the fluctuations in the capacitance C formed by the first transmitting electrode 31 and the receiving electrode 40, and the capacitance C formed by the second transmitting electrode 32 and the receiving electrode 40 are reduced, and contact detection noise can be suppressed.

[0053] (2) In the first embodiment, the distance Dh between the heating wire 20 and the transmitting electrode 30 and the distance Ds between the transmitting electrode 30 and Subject to the receiving 4 electrode 40 have a relationship of Dh ≦ Ds. According to this, as described with reference to the graphs of FIGS. 5 and 6, the surface average temperature of the heater device 1 can be improved, and the reaction intensity can be stably strengthened.

[0054] (3) In the first embodiment, the distance Dh between the heating wire 20 and the transmitting electrode 30 and the width Wh of the heating wire 20 have a relationship of Dh ≤ Wh. According to this, by making the distance Dh between the heating wire 20 and the transmitting electrode 30 smaller than the width Wh of the heating wire 20 and bringing the transmitting electrode 30 closer to the high-temperature heating wire 20, the amount of heat transfer from the heating wire 20 to the transmitting electrode 30 increases, so the surface average temperature can be improved. Also, as the distance Dh between the heating wire 20 and the transmitting electrode 30 is made closer, if the distance Ds between the transmitting electrode 30 and the receiving electrode 40 is made farther, the reaction intensity can be stably strengthened.

[0055] (4) In the first embodiment, the width Wd of the transmitting electrode 30 and the width Wi of the receiving electrode 40 have a relationship of Wd ≤ Wi. According to this, the capacitance formation of the capacitor by the two transmitting electrodes 30 and one receiving electrode 40 can be stabilized.

[0056] (5) In the first embodiment, the width Wi of the receiving electrode 40 and the distance Ds between the transmitting electrode 30 and Subject to the transmitting electrode 4 0 have a relationship of Wi ≤ Ds. According to this, as described with reference to the graphs of FIGS. 7 and 8, it is possible to suppress the occurrence of thermal discomfort to the user of the heater device 1 and to stably strengthen the reaction intensity of contact detection.

[0057] (6) In the first embodiment, the relationship between the area Sb of the heater main body 2 and the total value Sw of the areas of the surfaces of each wiring having the normal in the thickness direction of the heater main body 2 is 0.5× Sb ≧S w, and the lengths and widths of each wiring are set accordingly. Thereby, it becomes possible to reduce the occupancy rate of the conductive material per unit area of the heater main body 2, and it is possible to prevent the occurrence of thermal discomfort when the user's finger or the like touches the heater main body 2.

[0058] (Second Embodiment) The second embodiment will be described. The second embodiment is obtained by changing the shape of each wiring with respect to the first embodiment, and since the other aspects are the same as those of the first embodiment, only the parts different from the first embodiment will be described.

[0059] FIG. 9 is an enlarged view showing a part of the heater device 1 according to the second embodiment, and is a view showing a part corresponding to FIG. 4 referred to in the first embodiment. As shown in FIG. 9, in the second embodiment, the first heating wire 21, the first transmission electrode 31, the reception electrode 40, the second transmission electrode 32, and the second heating wire 22 are formed in a curved shape and a wavy shape, and the wirings are arranged parallel to each other and extend. Thus, each wiring of the heater device 1 is not limited to the linear one as shown in the first embodiment, and may be in a curved shape or a wavy shape as shown in this second embodiment.

[0060] Note that also in the second embodiment, the distance Dh between the heating wire 20 and the transmission electrode 30, and the distance Ds between the transmission electrode 30 and Subject to the reception 4 electrode Subject to 0 have a relationship of Dh ≤ Ds. Also, the distance Dh between the heating wire 20 and the transmission electrode 30, and the width Wh of the heating wire 20 have a relationship of Dh ≤ Wh. Also, the width Wd of the transmission electrode 30 and the width Wi of the reception electrode 40 have a relationship of Wd ≤ Wi. Also, the width Wi of the reception electrode 40 and the distance Ds between the transmission electrode 30 and 4 the reception 4 electrode 0 have a relationship of Wi ≤ Ds. Thereby, the heater device 1 of the second embodiment can also achieve the same operational effects as those of the first embodiment.

[0061] (Third to Fourth Embodiments) Next, the third to fourth embodiments will be described. Generally, the reaction intensity of contact detection when an object such as a user's finger contacts or approaches near the tip of the reception electrode 40 tends to be weaker than the reaction intensity when the object contacts or approaches the general part of the reception electrode 40 excluding the tip. Therefore, the third to fourth embodiments to be described next are aimed at increasing the reaction intensity near the tip of the reception electrode 40.

[0062] (Third Embodiment) As shown in FIGS. 10 and 11, the heater device 1 of the third embodiment also includes a heating wire 20, a transmitting electrode 30, and a receiving electrode 40 in a predetermined layer of the insulating base material 10. Since the basic configuration of each wiring is the same as that described in the first embodiment, the description thereof is omitted.

[0063] FIG. 11 shows the tip 44 of the receiving electrode 40 and the configuration in its vicinity. The transmitting electrode 30 is provided on three sides of the tip 44 of the receiving electrode 40. Hereinafter, for convenience of explanation, the transmitting electrode 30 shown in FIG. 11 will be referred to as the first transmitting electrode 31, the second transmitting electrode 32, and the third transmitting electrode 33. The first transmitting electrode 31 is disposed above the receiving electrode 40 in the plane of FIG. 11 and extends alongside the receiving electrode 40. The second transmitting electrode 32 is disposed on the side opposite to the first transmitting electrode 31 with respect to the receiving electrode 40 (that is, below the plane of FIG. 11 with respect to the receiving electrode 40) and extends alongside the receiving electrode 40. The third transmitting electrode 33 is a portion that connects the first transmitting electrode 31 and the second transmitting electrode 32 on the tip 44 side of the receiving electrode 40 (that is, on the right side of the plane of FIG. 11 with respect to the receiving electrode 40). Note that the first transmitting electrode 31, the second transmitting electrode 32, and the third transmitting electrode 33 are continuously formed of the same material. The heating wire 20 is disposed outside the first transmitting electrode 31, the second transmitting electrode 32, and the third transmitting electrode 33.

[0064] In the third embodiment, the tip 44 of the receiving electrode 40 is configured to have a higher areal density than the general portion 45 of the receiving electrode 40. Specifically, when the line width of the tip 44 of the receiving electrode 40 is Wit and the line width of the general portion 45 of the receiving electrode 40 is Wi, the relationship Wit > Wi is satisfied. Thereby, the receiving electrode 40 has a configuration in which the areal density of the tip 44 is high by making the line width Wit of the tip 44 wider than the line width Wi of the general portion 45.

[0065] Due to such shape characteristics of the tip 44 of the receiving electrode 40, when an object such as a user's finger contacts or approaches the tip 44 of the receiving electrode 40, the capacitance change ΔC becomes large, so the reaction intensity can be ensured. As described above, since it is in the relationship of C = f(shape characteristics × electrode length), even if the surface density of the tip 44 of the receiving electrode 40 is increased, it is only a part of the overall length of the receiving electrode 40, so the contribution to the capacitor capacitance C is limited, while the capacitance change ΔC can be increased.

[0066] Also, in the third embodiment, when the distance between the first transmitting electrode 31 and the second transmitting electrode 32 is Da and the distance in the direction in which the general portion 45 extends at the tip 44 of the receiving electrode 40 is Db, it has the relationship of Da ≤ Db. Thereby, when an object such as a user's finger contacts or approaches the tip 44 of the receiving electrode 40, the capacitance change ΔC can be made larger, and the reaction intensity of the tip 44 of the receiving electrode 40 can be made stronger and more stable.

[0067] Here, for comparison with the heater device 1 of the third embodiment, a part of the configuration of the heater device 100 of the comparative example is shown in FIG. 12. As shown in FIG. 12, the heater device 100 of the comparative example has a uniform line width from the general portion 45 to the tip 46 of the receiving electrode 40. Note that the heater device 100 of the comparative example has a different shape of the tip portion of the receiving electrode 40 compared to the third embodiment and is not a prior art.

[0068] The graph in FIG. 13 shows the simulation results of the electromagnetic field analysis performed by the inventors for the heater device 1 of the third embodiment and the heater device 100 of the comparative example. In this simulation, the index of the capacitance change ΔC when an object contacts was calculated with the regions indicated by the two-dot chain line circles X in FIGS. 11 and 12 as the centers, respectively.

[0069] According to the simulation results shown in FIG. 13, when the index of the change capacitance ΔC in the heater device 100 of the comparative example is set to 1, it can be seen that the index of the change capacitance ΔC in the heater device 1 of the third embodiment is about 1.3. Thus, when an object comes into contact with or approaches the vicinity of the tip 44 of the receiving electrode 40, the heater device 1 of the third embodiment can increase the reaction intensity by about 1.3 times compared to the heater device 100 of the comparative example.

[0070] (Fourth Embodiment) Similar to the third embodiment, the fourth embodiment is also aimed at increasing the reaction intensity at the tip of the receiving electrode 40. As shown in FIG. 14, in the fourth embodiment, the tip of the receiving electrode 40 has a plurality of receiving branch portions 47 branched from a portion continuously extending from the general portion 45. Further, the transmitting electrode 30 has a plurality of transmitting branch portions 34 branched from the first transmitting electrode 31 and the second transmitting electrode 32 at positions corresponding to the receiving branch portions 47. The plurality of receiving branch portions 47 and the plurality of transmitting branch portions 34 are alternately provided in the direction in which the general portion 45 of the receiving electrode 40 extends. In FIG. 14, four receiving branch portions 47 are provided at the tip of the receiving electrode 40, and four transmitting branch portions 34 are also provided at the transmitting electrode 30. However, the present invention is not limited to this, and the number of the receiving branch portions 47 and the transmitting branch portions 34 can be arbitrarily set. Further, the transmitting branch portion 34 may be configured to be branched from the third transmitting electrode 33.

[0071] Also in the fourth embodiment described above, by providing the receiving branch portion 47 at the tip of the receiving electrode 40, it is possible to increase the surface density of the tip of the receiving electrode 40. Further, by providing the transmitting branch portion 34 on the transmitting electrode 30, it is possible to increase the surface density of the portion of the transmitting electrode 30 corresponding to the tip of the receiving electrode 40. As a result, also in the fourth embodiment, due to the shape characteristics of the tip of the receiving electrode 40 and the shape characteristics of the surrounding transmitting electrode 30, the capacitance change ΔC becomes large when an object such as a user's finger contacts or approaches near the tip of the receiving electrode 40, so the reaction intensity can be ensured. Note that, as described above, since it is in the relationship of C = f(shape characteristics × electrode length), even if the surface density of the tip of the receiving electrode 40 is increased, it is only a part of the overall length of the receiving electrode 40, so the contribution to the capacitor capacitance C is limited, whereas the capacitance change ΔC can be increased.

[0072] (Other embodiments) (1) In each of the above embodiments, each wiring included in the heater device 1 has been described as having the relationship of Dh1 ≦ Ds1 and Dh2 ≦ Ds2, but it is not limited thereto, and it may have the relationship of Dh1 < Ds1 and Dh2 < Ds2. As a result, an effect greater than Dh1 = Ds1 and Dh2 = Ds2 can be obtained. Further, each wiring may have a dimensional relationship (for example, Dh1 × 1.1 < Ds1 and Dh2 × 1.1 < Ds2) that does not include manufacturing tolerances, etc., with respect to Dh1 = Ds1 and Dh2 = Ds2, as necessary.

[0073] (2) In each of the above embodiments, each wiring included in the heater device 1 has been described as having the relationship of Dh1 ≦ Wh1 and Dh2 ≦ Wh2, but it is not limited thereto, and it may have the relationship of Dh1 < Wh1 and Dh2 < Wh2. As a result, an effect greater than Dh1 = Wh1 and Dh2 = Wh2 can be obtained. Further, each wiring may have a dimensional relationship (for example, Dh1 × 1.1 < Wh1 and Dh2 × 1.1 < Wh2) that does not include manufacturing tolerances, etc., with respect to Dh1 = Wh1 and Dh2 = Wh2, as necessary.

[0074] (3) In each of the above embodiments, each wiring included in the heater device 1 has been described as having the relationship of Wd1 ≦ Wi and Wd2 ≦ Wi. However, it is not limited to this, and it may have the relationship of Wd1 < Wi and Wd2 < Wi. Thereby, an effect greater than Wd1 = Wi and Wd2 = Wi can be obtained. Also, each wiring may, if necessary, have a dimensional relationship that does not include manufacturing tolerances, etc. with respect to Wd1 = Wi and Wd2 = Wi (for example, Wd1 × 1.1 < Wi and Wd2 × 1.1 < Wi).

[0075] (4) In each of the above embodiments, each wiring included in the heater device 1 has been described as having the relationship of Wi ≦ Ds1 and Wi ≦ Ds2. However, it is not limited to this, and it may have the relationship of Wi < Ds1 and Wi < Ds2. Thereby, an effect greater than Wi = Ds1 and Wi = Ds2 can be obtained. Also, each wiring may, if necessary, have a dimensional relationship that does not include manufacturing tolerances, etc. with respect to Wi = Ds1 and Wi = Ds2 (for example, Wi × 1.1 < Ds1 and Wi × 1.1 < Ds2).

[0076] (5) In the above-described third embodiment, each wiring included in the heater device 1 has been described as having the relationship of Da ≦ Db. However, it is not limited to this, and it may have the relationship of Da < Db. Thereby, an effect greater than Da = Db can be obtained. Also, each wiring may, if necessary, have a dimensional relationship that does not include manufacturing tolerances, etc. with respect to Da = Db (for example, Da × 1.1 < Db).

[0077] The present invention is not limited to the above-described embodiments, and can be appropriately modified within the scope described in the claims. Also, the above embodiments are not unrelated to each other, and can be appropriately combined except in cases where the combination is clearly impossible. Further, in the above embodiments, it goes without saying that the elements constituting the embodiments are not necessarily essential except in cases where it is clearly stated as essential or where it is considered to be clearly essential in principle. Also, in the above embodiments, when numerical values such as the number, numerical value, quantity, range, etc. of the components of the embodiment are mentioned, they are not limited to that specific number except in cases where it is clearly stated as essential or where it is clearly limited to a specific number in principle. Also, in the above embodiments, when referring to the shape, positional relationship, etc. of the components, etc., they are not limited to that shape, positional relationship, etc. except in cases where it is clearly stated or where it is clearly limited to a specific shape, positional relationship, etc. in principle.

Explanation of Signs

[0078] 1 Heater device 10 Insulating base material 20 Heating wire 21 First heating wire 22 Second heating wire 30 Transmitting electrode 31 First transmitting electrode 32 Second transmitting electrode 40 Receiving electrode 80 Control unit

Claims

1. In a heater device, an insulating base material (10), a heating wire (20) having a first heating wire (21) and a second heating wire (22) and generating heat when energized, a receiving electrode (40) provided between the first heating wire and the second heating wire, a transmitting electrode (30) having a first transmitting electrode (31) provided between the first heating wire and the receiving electrode and a second transmitting electrode (32) provided between the second heating wire and the receiving electrode, controlling the energization of the heating wire so that the temperature of the region where the heating wire is disposed on the insulating base material is a predetermined temperature, and when contact or proximity of an object is detected due to a change in the capacitance between the transmitting electrode and the receiving electrode, reducing the amount of energization of the heating wire below the normal state or stopping the energization, a control unit (80), the first heating wire, the first transmitting electrode, the receiving electrode, the second transmitting electrode, and the second heating wire are provided so as to extend side by side in this order in a predetermined layer of the insulating base material, when the distance between the first heating wire and the first transmitting electrode is Dh1, the distance between the first transmitting electrode and the receiving electrode is Ds1, the distance between the second heating wire and the second transmitting electrode is Dh2, and the distance between the second transmitting electrode and the receiving electrode is Ds2, a heater device having a relationship of Dh1 ≤ Ds1 and Dh2 ≤ Ds2.

2. when the width of the first heating wire is Wh1 and the width of the second heating wire is Wh2, the heater device according to claim 1, having a relationship of Dh1 ≤ Wh1 and Dh2 ≤ Wh2.

3. when the width of the first transmitting electrode is Wd1, the width of the second transmitting electrode is Wd2, and the width of the receiving electrode is Wi, the heater device according to claim 1 or 2, having a relationship of Wd1 ≤ Wi and Wd2 ≤ Wi.

4. when the width of the receiving electrode is Wi, The heater device according to any one of claims 1 to 3, having a relationship of Wi ≤ Ds1 and Wi ≤ Ds2.

5. When the area of the surface of the insulating base material on which the heating wire, the receiving electrode, and the transmitting electrode are provided is Sb, and the total value of the areas of the surfaces of the heating wire, the receiving electrode, and the transmitting electrode perpendicular to the thickness direction of the insulating base material is Sw, The heater device according to any one of claims 1 to 4, having a relationship of 0.5 × Sb ≥ Sw.

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