Heater Device

Abstract

A heater device capable of efficiently heating an object to be heated is provided. [Solution] One aspect of the present invention is a heater device 1 comprising a heat-generating member 10 including a ceramic PTC (Positive Temperature Coefficient) heat-generating element with electrode layers on both sides, and a case 20 that houses the heat-generating member and is positioned opposite an object to be heated. When the object to be heated is a vehicle window 100, the heat-generating member and the case are positioned outside the optical path area S of an information capturing means 500 that optically captures information about the outside of the vehicle from inside the vehicle through the window.

Description

[Technical Field]

[0001] The present invention relates to a heater device for heating an object to be heated, for example, a heater device for deicing, defrosting, and preventing fogging of vehicle windows. [Background technology]

[0002] As a technology for heating vehicle windows, Patent Document 1 discloses a screen heater system having a heater element attached to a sensor bracket that mounts a sensor that detects the external environment through the screen, and a heating control circuit that controls the heating state of the heater element.

[0003] Patent document 2 discloses a heating device that heats a portion of the windshield located on an information acquisition path of an outside-vehicle information acquisition means that is placed inside the vehicle and acquires information outside the vehicle, the heating device comprising: a hood that is provided inside the vehicle below the information acquisition path of the outside-vehicle information acquisition means; and a heating element that is provided on the surface or inside the hood and has a PTC heater.

[0004] Patent Document 3 discloses an adapter for a windshield transmission sensor, the adapter comprising: a housing having a first surface that can be attached to the inner surface of the windshield and a second surface that can be attached to the front surface of the windshield transmission sensor, the housing defining an enclosed volume between the first surface and the second surface, the enclosed volume being positioned to enable detection by the windshield transmission sensor through an area of ​​the windshield adjacent to the enclosed volume; and an electric resistance heater supported by the housing, the electric resistance heater communicating with the enclosed volume and heating air within the enclosed volume to heat the area of ​​the windshield adjacent to the enclosed volume, thereby improving the transparency of the windshield against moisture in the environment. [Prior art documents] [Patent documents]

[0005] [Patent Document 1] Japanese Patent Publication No. 2021-044097 [Patent Document 2] Japanese Patent Application Publication No. 2019-093794 [Patent Document 3] Special Publication No. 2017-537837 Summary of the Invention [Problem to be solved by the invention]

[0006] Fogging, frost, and ice on windows and mirrors reduce functionality. In recent years, various sensors have been installed on vehicle windows to capture information about the outside of the vehicle through the windows. This has led to a demand for faster window defogging, defrosting, and deicing. Energy saving in heater devices is also an important factor.

[0007] The object of the present invention is to provide a heater device that can efficiently heat an object to be heated. [Means for solving the problem]

[0008] One aspect of the present invention is a heater device for heating an object to be heated, comprising a heat-generating member including a ceramic PTC (Positive Temperature Coefficient) heat-generating element with electrode layers on both sides, and a case that houses the heat-generating member and is positioned opposite the object to be heated.

[0009] With this configuration, by using a ceramic PTC heating element, the heat generation density is higher than that of electric heating wire heating elements or polymer-based PTC heating elements, and heat can be generated instantly even at low voltage, allowing the object to be heated to be heated efficiently.

[0010] In the heater device, the object to be heated may be a vehicle window, and the heat-generating member and the case may be disposed outside the optical path area of ​​an information capture means that optically captures information about the outside of the vehicle from inside the vehicle through the window, thereby efficiently heating the window that is in the optical path area without interfering with the optical path area of ​​the information capture means.

[0011] In the heater device, the object to be heated may be a vehicle mirror, and the heat-generating member and the case may be disposed on the opposite side of the mirror from the reflective surface thereof, thereby allowing the mirror to be efficiently heated from the opposite side of the reflective surface thereof.

[0012] In the heater device, the heat generating member may further include an insulating member provided between the PTC heat generating element and the case. In this case, the heat generating member may be waterproof between the PTC heat generating element and the case. By providing the insulating member between the PTC heat generating element and the case, leakage or short circuit through the case is prevented. Furthermore, by providing waterproofing between the PTC heat generating element and the case, an insulated and waterproof heat generating member is configured. [Effects of the Invention]

[0013] According to the present invention, it is possible to provide a heater device that can efficiently heat an object to be heated. [Brief explanation of the drawings]

[0014] [Figure 1] 1 is a schematic view illustrating a heater device according to a first embodiment. [Figure 2] FIG. 2 is an exploded perspective view illustrating the configuration of a heater device. [Figure 3] FIG. 2 is a cross-sectional view illustrating the configuration of a heater device. [Figure 4] FIG. 10 is a schematic diagram illustrating another installation example (part 1). [Figure 5] 10(a) and 10(b) are schematic diagrams illustrating another installation example (part 2). [Figure 6] 10(a) and 10(b) are schematic diagrams illustrating another installation example (third example). [Figure 7] 10(a) and 10(b) are schematic diagrams illustrating another installation example (No. 4). [Figure 8] 10(a) and 10(b) are schematic views illustrating a heater device according to a second embodiment. [Figure 9] FIG. 1 is a configuration diagram of a heating experiment using a heater device according to the present embodiment. DETAILED DESCRIPTION OF THE INVENTION

[0015] DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will now be described with reference to the accompanying drawings. In the following description, the same components will be designated by the same reference numerals, and the description of components that have already been described will be omitted as appropriate.

[0016] (First embodiment) FIG. 1 is a schematic view illustrating the heater device according to the first embodiment. FIG. 2 is an exploded perspective view illustrating the configuration of the heater device. FIG. 3 is a cross-sectional view illustrating the configuration of the heater device. The heater device 1 according to the first embodiment is a device that heats a vehicle window 100 as a heating object. The heater device 1 includes a heat-generating member 10 including a PTC (Positive Temperature Coefficient) heat-generating element 11, and a case 20 that houses the heat-generating member 10 and is disposed opposite the window 100.

[0017] The PTC heating element 11 generates heat when a voltage is applied. The PTC heating element 11 has a positive temperature coefficient. That is, when the temperature exceeds the Curie point, the resistance increases, limiting further temperature rise. By using the PTC heating element 11, temperature control becomes easier and power consumption can be reduced.

[0018] In this embodiment, a ceramic type (ceramic-containing) PTC heating element 11 is used. The positive temperature coefficient of the ceramic PTC heating element 11 can be changed, for example, by adding a small amount of rare earth elements to barium titanate (BaTiO3). The ceramic PTC heating element 11 can generate heat instantaneously even at low voltages (several volts to several tens of volts) and can generate heat at a constant temperature even with slight voltage fluctuations. For this reason, it is particularly suitable for use with a power source that experiences voltage fluctuations, such as a 12- or 24-volt automotive battery.

[0019] Electrode layers 12a and 12b are provided on the front and back surfaces of the PTC heating element 11. Metals such as silver (Ag) and aluminum (Al) are used for the electrode layers 12a and 12b. These metals are formed by, for example, thermal spraying onto the front and back surfaces of the PTC heating element 11. The electrode layers 12a and 12b are in ohmic contact with the PTC heating element 11.

[0020] The PTC heating element 11 is sandwiched between a pair of electrode portions 13a and 13b. One electrode portion 13a is electrically connected to one electrode layer 12a of the PTC heating element 11, and the other electrode portion 13b is electrically connected to the other electrode layer 12b of the PTC heating element 11. A conductive cable 14a is connected to the electrode portion 13a, and a conductive cable 14b is connected to the electrode portion 13b. By connecting the conductive cables 14a and 14b to a power source, a voltage is applied from the pair of electrode portions 13a and 13b to the pair of electrode layers 12a and 12b to the PTC heating element 11, causing heat to be generated.

[0021] The case 20 that houses the heat-generating member 10 is made of, for example, metal (aluminum, etc.) or heat-resistant resin. The case 20 has a space 20h that houses the heat-generating member 10. By housing the heat-generating member 10 in the space 20h, the PTC heat-generating element 11 is sandwiched between the pair of electrodes 13a, 13b.

[0022] The heat generating member 10 may further include an insulating member 15 provided between the PTC heating element 11 and the case 20. The insulating member 15 is preferably made of a flexible, thermally conductive, and electrically insulating polyimide film, for example, approximately 0.05 mm thick. When the heat generating member 10 is housed in the space 20h of the case 20, the pair of electrodes 13a, 13b that sandwich the PTC heating element 11 are surrounded by the insulating member 15, made of, for example, polyimide film, and the heat generating member 10 is housed in this state within the space 20h of the case 20. This electrically insulates the electrodes 13a, 13b and the PTC heating element 11 from the case 20, preventing leakage or short circuits through the case 20.

[0023] The heat generating member 10 may be waterproof between the PTC heat generating element 11 and the case 20. For example, the open end of the space 20h of the case 20 accommodating the heat generating member 10 is sealed with a sealant (not shown) or a cap (not shown) to make the space 20h watertight. This makes the space 20h of the case 20 waterproof, and an insulating, waterproof heat generating member 10 is formed.

[0024] Here, the waterproofness preferably means waterproofness and dustproofness that meets, for example, the IP67 standard of the IP code (IEC: International Electrotechnical Commission). IP67 means that the device has dustproof properties that prevent dust from entering the device, and waterproof properties that prevent water from entering the device even if it is temporarily submerged under a certain water pressure.

[0025] The heat-generating member 10 and the case 20 are arranged outside an optical path region S of an information acquisition means 500 that optically acquires information about the outside of the vehicle from inside the vehicle through the window 100. The information acquisition means 500 is, for example, a camera that acquires images or an infrared sensor. The information acquisition means 500 is housed in a cover 510 that is attached to the interior of the vehicle. The heater device 1 is arranged, for example, in front of the information acquisition means 500 on the cover 510, in a position facing the window 100. Here, facing includes being arranged parallel or non-parallel with a predetermined gap from the window 100 (the object to be heated), as well as being in contact with the window 100 (the object to be heated). Furthermore, contact includes not only direct contact but also indirect contact (contact with a member interposed therebetween).

[0026] By arranging the heat-generating member 10 and the case 20 outside the optical path region S, it becomes possible to heat the window 100 without interfering with the optical path region S of the information acquisition means 500. Heat from the heat-generating member 10 is transferred via the case 20 to the portion Sa of the opposing window 100 that corresponds to the optical path region S, and the portion Sa is heated.

[0027] In recent years, the information capture device 500 installed in a vehicle has become an important means used to improve safety and autonomous driving. If the portion Sa of the optical path region S of the window 100 becomes cloudy due to condensation or if frost or ice accumulates, the information capture device 500 will not function properly. The heater device 1 according to this embodiment uses a ceramic PTC heating element 11, which has a higher heat density than electric heating wire heating elements or polymer-based PTC heating elements and can generate heat instantly even at low voltage. Furthermore, ceramic PTC heating elements can easily adjust their heating characteristics, including positive temperature coefficients, by adjusting barium titanate (BaTiO3) and additives. This allows for easy configuration based on the material of the heated object, the distance to the heated object, the target heating range, power consumption, and other factors. Using such a ceramic PTC heating element 11 allows for efficient heating of the portion Sa of the window 100 in a short time and with low power consumption, thereby preventing fogging, removing fog, defrosting, and deicing, thereby enabling the information capture device 500 to function as quickly as possible.

[0028] FIG. 4 is a schematic diagram illustrating another installation example (part 1). 4, the heater device 1 according to this embodiment is arranged next to an information acquisition means 500 provided inside the vehicle. By juxtaposing the heater device 1 next to the information acquisition means 500, it is possible to effectively suppress interference of the heater device 1 with the optical path region S of the information acquisition means 500. When two information acquisition means 500 are arranged on the left and right, it is preferable to arrange the heater device 1 between them and heat the portions Sa that overlap with the two optical path regions S of the opposing windows 100.

[0029] 5(a) and (b) are schematic diagrams for explaining another installation example (part 2), where (a) is a perspective view and (b) is a cross-sectional view. In the example shown in FIG. 5, the heater device 1 according to this embodiment is attached to the interior surface of a vehicle window 100. The heater device 1 is attached to the outside of a portion Sa where the optical path region S of the information capturing means 500 and the window 100 overlap. The heater device 1 is preferably attached near the portion Sa of the window 100. This allows the area around the heater device 1 on the window 100 (particularly the portion Sa) to be heated quickly. When two information capturing means 500 are arranged on the left and right, by arranging the heater device 1 between the two portions Sa where the optical path region S of each information capturing means 500 and the window 100 overlap, it becomes possible to efficiently heat the two portions Sa with one heater device 1.

[0030] 6(a) and (b) are schematic diagrams for explaining another installation example (third example), where (a) is a perspective view and (b) is a cross-sectional view. In the example shown in FIG. 6 , the heater device 1 according to this embodiment is incorporated into a housing 620 of a drive recorder 600. A camera 610 of the drive recorder 600 is an example of the information capturing means 500. The drive recorder 600 is attached to, for example, a window 100 by a mounting base 630. The drive recorder 600 may be attached to a rearview mirror (not shown) or may be incorporated into the rearview mirror. When incorporated into the rearview mirror, the housing of the rearview mirror doubles as the housing 620 of the drive recorder 600. The camera 610 is disposed on the surface of the housing 620 of the drive recorder 600 facing the window 100. The heater device 1 according to this embodiment is preferably disposed in a position aligned with the camera 610 on the surface of the housing 620 facing the window 100. As a result, a portion Sa of the window 100 facing the heater device 1 and overlapping the optical path area S of the camera 610 is heated.

[0031] 7(a) and (b) are schematic diagrams for explaining another installation example (No. 4), where (a) is a perspective view and (b) is a cross-sectional view. In the example shown in FIG. 7, the heater device 1 according to this embodiment is incorporated into a mounting base 630 of a drive recorder 600. The mounting base 630 is adhered to the window 100 with double-sided tape or the like. By incorporating the heater device 1 according to this embodiment into the surface of the mounting base 630 that is in close contact with the window 100, the heater device 1 comes into close contact with the window 100. The double-sided tape may be attached to the mounting base 630 around the heater device 1, or may be attached to the mounting base 630 including the portion where the heater device 1 is incorporated. In this case, a heat-resistant double-sided tape is preferred.

[0032] By incorporating the heater device 1 into the mounting base 630, it is possible to effectively suppress interference of the heater device 1 with the optical path region S of the information capturing means 500. In such an installation, heat is transferred from the position on the window 100 where the heater device 1 is in close contact to the portion Sa that overlaps with the optical path region S of the camera 610, causing heating. Furthermore, by incorporating the heater device 1 into the mounting base 630, the mounting region of the heater device 1 is included in the mounting region of the mounting base 630 on the window 100, allowing for effective use of the space of the window 100.

[0033] Although the above example shows an application to the drive recorder 600, it can also be applied to a rear camera. When the rear camera is installed on the interior side of the rear window, the heater device 1 provided in the rear camera heats at least a predetermined position on the rear window (for example, a position overlapping the optical path area of ​​the rear camera), thereby preventing fogging, removing fog, defrosting, and deicing the rear window at that position. Furthermore, when a component (such as a rearview mirror or ETC device) or a base is tightly connected to the window 100 other than the drive recorder 600, the heater device 1 may be incorporated into the component or base.

[0034] (Second embodiment) 8(a) and (b) are schematic diagrams illustrating a heater device according to the second embodiment, where (a) is a perspective view and (b) is a cross-sectional view. 8(a) and 8(b), the heater device 1 according to the second embodiment is a device that heats a mirror 710, which is an object to be heated and is provided on a vehicle side mirror 700. In this embodiment, the heat-generating member 10 and the case 20 of the heater device 1 are arranged on the side (rear surface 710b) of the mirror 710 opposite to the reflective surface 710a.

[0035] Side mirror 700 includes a housing 720 that is open on the rear side of the vehicle, a mirror 710 that is placed in the opening of housing 720, a drive mechanism 730 that is incorporated into housing 720, and a back cover 740 that is provided on a back surface 710b side of mirror 710. Back cover 740 that is connected to mirror 710 is linked to drive mechanism 730 that is composed of a motor and a link, and the operation of drive mechanism 730 is transmitted from back cover 740 to mirror 710, allowing the angle of mirror 710 to be adjusted.

[0036] The heater device 1 according to this embodiment is disposed between the mirror 710 and the rear cover 740. The heater device 1 heats the mirror 710 from the rear surface 710b side of the mirror 710, thereby transferring heat to the reflective surface 710a of the mirror 710. Here, the case 20 of the heater device 1 may be in contact with the rear surface 710b of the mirror 710. By disposing the case 20 of the heater device 1 so that it is in contact with the rear surface 710b, the heat of the heater device 1 can be immediately transferred from the case 20 to the mirror 710.

[0037] The case 20 of the heater device 1 may be disposed with a gap between it and the rear surface 710b. By disposing the case 20 of the heater device 1 away from the rear surface 710b, heat from the heater device 1 can be easily transferred from the case 20 to the mirror 710 over a wide area. The heater device 1 may also be disposed with a highly thermally conductive sheet sandwiched between the case 20 of the heater device 1 and the rear surface 710b of the mirror 700. This makes it easier to transfer heat from the heater device 1 to the mirror 710 over a wide area and in a short time.

[0038] By using a ceramic PTC heating element 11 as in the heater device 1 of this embodiment, the reflective surface 710a of the mirror 710 can be efficiently heated to prevent fogging, remove fogging, defrost and de-ice, thereby allowing the mirror 710 to perform its functions.

[0039] Although the second embodiment shows an example in which the heater device 1 is applied to the side mirror 700, it can also be applied to a rearview mirror.

[0040] (Experimental results) FIG. 9 is a configuration diagram of a heating experiment using the heater device according to this embodiment. 9, the heater device 1 according to this embodiment was attached to glass G, and the change in the surrounding temperature was measured. In the experiment, the surrounding area of ​​the heater device 1 was divided into a left area A, a right area B, and a lower area C, and the temperature was measured at five points (measurement distances of 1 cm to 5 cm (see circles in the figure)) each 1 cm away from the end of the heater device 1 in each area.

[0041] The measurement results are shown in Tables 1 and 2. Table 1 shows the results of the first measurement, and Table 2 shows the results of the second measurement. The ambient temperature during the first measurement was 24.1°C, and the surface temperature of the heater device 1 reached 112.9°C after approximately 180 seconds of power application (the time it took for the temperature to stabilize). The ambient temperature during the second measurement was 24.1°C, and the surface temperature of the heater device 1 reached 113.9°C after approximately 180 seconds of power application.

[0042] [Table 1]

[0043] [Table 2]

[0044] Although it depends on the temperature and humidity conditions, condensation is removed by a temperature rise of several degrees Celsius. The heater device 1 having the ceramic PTC heating element 11 as in this embodiment can remove condensation in a short time after power is turned on.

[0045] As described above, according to this embodiment, by using the ceramic PTC heating element 11, it is possible to provide a heater device 1 that has a higher heat generation density than electric heating wire heating elements or polymer PTC heating elements, and can generate heat instantly even at low voltage and efficiently heat an object to be heated.

[0046] Although the present invention has been described above with reference to the present embodiment and its application examples, the present invention is not limited to these examples. For example, any combination of features of the above-described embodiments or their application examples, or any combination of elements appropriately added, deleted, or modified by a person skilled in the art, is also included within the scope of the present invention as long as it includes the gist of the present invention. [Industrial Applicability]

[0047] The present invention is suitable for use in heating moving objects such as automobiles, motorcycles, trains, ships, and airplanes, as well as components of these objects, convex mirrors, traffic lights, and other objects that become ineffective due to fogging caused by condensation, or the accumulation of frost and ice. [Explanation of symbols]

[0048] 1...Heater device 10...heat generating member 11...PTC heating element 12a, 12b...electrode layer 13a, 13b...electrode part 14a, 14b...Conductive cables 15...Insulating member 20…case 20h…Space 100...Window 500...Information collection method 510...Cover 600...Drive recorder 610...Camera 620,720…Housing 630...Mounting base 700...Side mirror 710...Mirror 710a…Reflective surface 710b…Back side 730...Drive mechanism 740...Back cover S...Optical path area Sa... part

Claims

1. A heater device for heating an object to be heated, a heat generating member including a ceramic PTC (Positive Temperature Coefficient) heat generating element having electrode layers on its front and back sides; a case that houses the heat-generating member and is disposed opposite the object to be heated; A heater device comprising:

2. the object to be heated is a vehicle window, 2. The heater device according to claim 1, wherein the heat generating member and the case are arranged outside an optical path area of ​​an information capturing means that optically captures information about the outside of the vehicle from inside the vehicle through the window.

3. the object to be heated is a mirror of a vehicle, The heater device according to claim 1 , wherein the heat-generating member and the case are disposed on an opposite side to a reflecting surface of the mirror.

4. 4. The heater device according to claim 1, wherein the heat generating member further comprises an insulating member provided between the PTC heat generating element and the case.

5. 5. The heater device according to claim 4, wherein the heat generating member has a waterproof property between the case and the PTC heat generating element.

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