Windshield

Abstract

The present invention is a windshield on which can be disposed an information acquisition device for acquiring information from outside of a vehicle by radiating and / or receiving light. The windshield comprises: a glass plate; and a heating wire provided on the glass plate and to which an electric current is applied. The glass panel has at least one information acquisition region that faces the information acquisition device and through which light passes. The heating wire comprises a plurality of wire-like main parts that pass through at least the interior of the information acquisition region, and wire-like connection parts connecting the plurality of main parts. At least one of the connection parts has a heat suppression means for suppressing heat when the electric current is applied.

Description

[Technical field]

[0001] The present invention relates to a windshield on which an information acquisition device can be mounted that acquires information from outside the vehicle by emitting and / or receiving light. [Background technology]

[0002] In recent years, the safety performance of automobiles has been improved dramatically, and one such improvement is a safety system that detects the distance to the vehicle ahead and the speed of the vehicle ahead, and automatically applies the brakes when the vehicle approaches abnormally close, in order to avoid a collision with the vehicle ahead. Such a system measures the distance to the vehicle ahead using a laser radar or a camera. The laser radar or camera is generally placed inside the windshield, and performs measurements by shining infrared light or other light forward (for example, Patent Document 1). [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2006-96331 A Summary of the Invention [Problem to be solved by the invention]

[0004] As described above, the measuring device such as the laser radar and the camera is disposed on the inner side of the glass plate constituting the windshield, and emits and receives light through the glass plate. However, on a cold day or in a cold region, the glass plate may fog up. However, if the glass plate fogs up, the measuring device may not be able to emit light accurately or may not be able to receive light accurately. This may result in the distance between vehicles not being calculated accurately.

[0005] Such problems are not limited to inter-vehicle distance measuring devices, but can occur in general with information acquisition devices that acquire information from outside the vehicle by receiving light, such as cameras, ETCs, etc. The present invention has been made to solve the above problems, and has an object to provide a windshield to which an information acquisition device that irradiates and / or receives light through a glass plate can be attached, the windshield being capable of accurately irradiating and / or receiving light and accurately processing information. [Means for solving the problem]

[0006] Item 1. A windshield on which an information acquisition device that acquires information from outside the vehicle by irradiating and / or receiving light can be disposed, A glass plate and a heating wire provided on the glass plate and to which an electric current is applied; Equipped with the glass plate has at least one information acquisition area facing the information acquisition device and through which the light passes; The heating wire includes a plurality of linear body portions passing through at least the inside of the information acquisition region, and linear connecting portions connecting the plurality of body portions, A windshield, wherein at least one of the connecting portions has a heat suppression means for suppressing heat generation when an electric current is applied thereto.

[0007] Item 2. As the heat suppression means, at least one of the connecting parts has at least one bent part, Item 2. The windshield according to item 1, wherein a resistance value per unit length of the bent portion is smaller than a resistance value per unit length of the main body portion.

[0008] Item 3. The heat generation suppression means Item 3. The windshield according to item 1 or 2, wherein a resistance value per unit length of the connecting portion is smaller than a resistance value per unit length of the main body portion.

[0009] Item 4. At least one of the connecting portions has at least one bent portion, 4. The windshield according to any one of items 1 to 3, wherein at least one of the connecting portions has at least one bypass heating wire.

[0010] Item 5. The windshield according to item 4, wherein at least one of the connecting portions has two of the bypass heating wires.

[0011] Item 6. The windshield according to item 4, wherein every connecting portion has two of the bypass heating wires.

[0012] Item 7. The windshield according to any one of items 2 to 6, wherein a line width of at least a part of the bent portion is wider than a line width of a portion of the connecting portion other than the bent portion.

[0013] Item 8. The windshield according to any one of items 2 to 7, wherein a thickness of at least a part of the bent portion is greater than a thickness of a portion of the connecting portion other than the bent portion.

[0014] Item 9. The windshield according to any one of items 2 to 8, wherein the angle between the heating wires constituting the bent portion is 15 to 60 degrees.

[0015] Item 10. The windshield according to any one of Items 2 to 9, wherein the bent portion has a length of 1 to 20 mm.

[0016] Item 11. The windshield according to any one of items 2 to 10, wherein the line width of the bent portion is 1.2 times or more the line width of the portion of the connecting portion other than the bent portion.

[0017] Item 12. The windshield according to any one of Items 2 to 11, wherein at least a part of the bent portion has a line width of 0.3 to 1.0 mm.

[0018] Item 13. The windshield according to any one of items 2 to 12, wherein the thickness of the bent portion is 1.2 times or more the thickness of the portion of the connecting portion other than the bent portion.

[0019] Item 14. The windshield according to any one of items 2 to 13, wherein the bent portion is formed in an arc shape.

[0020] Item 15. The windshield according to item 14, wherein the bent portion has a radius of curvature of 1 to 10 mm.

[0021] Item 16. The windshield according to any one of Items 2 to 15, wherein the bent portion is provided with a conductive portion having an outer diameter larger than the line width of the heating wire that constitutes the bent portion.

[0022] Item 17. The windshield according to item 16, wherein the maximum outer diameter of the conductive portion is 10 mm or less.

[0023] Item 18. A plurality of the main body portions are arranged approximately in parallel, Item 18. The windshield according to any one of items 1 to 17, wherein the spacing between the main body portions is 1.2 times or more the width of the heating wire.

[0024] Item 19. The windshield according to any one of items 1 to 18, wherein the number of the main body parts is 3 to 50.

[0025] Item 20. The total area of ​​the plurality of main body parts is 2500 mm 2 20. The windshield according to any one of items 1 to 19.

[0026] Item 21. The windshield according to any one of items 1 to 20, wherein the main body is inclined at an angle α of 30 degrees or less with respect to the horizontal direction.

[0027] Item 22. As the heat suppression means, at least one of the connecting parts has at least one bent part, Item 22. The windshield according to any one of items 1 to 21, wherein the temperature difference dT defined at the bent portion is less than 15°C. Here, dT is |bs|, s is the average temperature of the heating wire at two points 35 mm away from the apex of the bent portion, and b is the temperature of the heating wire at the apex. Effect of the Invention

[0028] According to the present invention, in a windshield to which an information acquisition device that irradiates and / or receives light through a glass plate can be attached, light can be accurately irradiated and / or received, and information can be accurately processed. [Brief description of the drawings]

[0029] [Figure 1] 1 is a plan view showing one embodiment of a windshield according to the present invention. FIG. [Diagram 2] FIG. 2 is a cross-sectional view of FIG. [Diagram 3] 1 is a block diagram showing a schematic configuration of an in-vehicle system; [Figure 4] FIG. [Diagram 5] FIG. 4 is a plan view showing an example of a bent portion of a heating wire. [Figure 6] FIG. 11 is a plan view showing another example of the heating wire. [Figure 7] FIG. 11 is a plan view showing another example of an opening and a heating wire. [Figure 8] FIG. 11 is a plan view showing another example of an opening and a heating wire. [Figure 9A] FIG. 1 is a schematic diagram showing a basic structure of a connecting portion according to Examples 1 to 11. [Figure 9B] 13 is a schematic diagram showing the structure of a connecting portion according to a comparative example. FIG. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0030] First, the configuration of the windshield according to this embodiment will be described with reference to Figures 1 and 2. Figure 1 is a plan view of the windshield, and Figure 2 is a cross-sectional view of Figure 1. For ease of explanation, the up-down direction in Figure 1 will be referred to as "up-down", "vertical", and "length", and the left-right direction in Figure 1 will be referred to as "left-right". Figure 1 illustrates the windshield as seen from the inside of the vehicle. That is, the back side of the paper in Figure 1 is the outside of the vehicle, and the front side of the paper in Figure 1 is the inside of the vehicle.

[0031] This windshield has a trapezoidal laminated glass 10 and is installed on the vehicle body in an inclined state. The laminated glass 10 has an outer glass sheet 11, an inner glass sheet 12, and an intermediate film 13 arranged between them. A shielding layer 4 is laminated on the surface of the inner glass sheet 12 facing the vehicle interior, and this shielding layer 4 blocks the view from outside the vehicle. An opening 43 is formed in this shielding layer 4, and through this opening 43, the situation outside the vehicle can be photographed by a photographing device 2 arranged in the vehicle. That is, this opening 43 constitutes a photographing window. Furthermore, a frame-shaped bracket 6 is fixed on the shielding layer 4 of the inner glass sheet 12, and the photographing device 2 is attached to this bracket 6. Since the bracket 6 is formed on a frame and fixed on the shielding layer 4, the bracket 6 is not visible from outside the vehicle. Furthermore, an electric heating wire 8 is arranged on the inner glass sheet 12 so as to pass through the opening 43. Each component will be described in detail below.

[0032] <1. Laminated glass> Fig. 3 is a cross-sectional view of a laminated glass. As shown in the figure, this laminated glass 10 includes an outer glass plate 11 and an inner glass plate 12, and a resin interlayer film 13 is disposed between these glass plates 11, 12. The components thereof will be described below.

[0033] <1-1. Glass plate> First, the outer glass plate 11 and the inner glass plate 12 will be described. The outer glass plate 11 and the inner glass plate 12 can be made of known glass plates, and can also be made of heat absorbing glass, general clear glass, green glass, or UV green glass. However, these glass plates 11 and 12 need to achieve a visible light transmittance that meets the safety standards of the country in which the automobile is used. For example, the outer glass plate 11 can ensure the required solar radiation absorptance, and the inner glass plate 12 can adjust the visible light transmittance to meet the safety standards. Examples of clear glass, heat absorbing glass, and soda lime glass are shown below.

[0034] (Clear glass) SiO2:70~73% by mass Al2O3:0.6~2.4% by mass CaO: 7~12% by mass MgO: 1.0~4.5% by mass RO: 13 to 15 mass% (R is an alkali metal) Total iron oxide converted to Fe2O3 (T-Fe2O3): 0.08-0.14 mass%

[0035] (Heat absorbing glass) The composition of the heat ray absorbing glass can be, for example, based on the composition of clear glass, with the ratio of total iron oxide (T-Fe2O3) converted to Fe2O3 being 0.4 to 1.3 mass%, the ratio of CeO2 being 0 to 2 mass%, the ratio of TiO2 being 0 to 0.5 mass%, and the glass skeletal components (mainly SiO2 and Al2O3) being reduced by the increases in T-Fe2O3, CeO2, and TiO2.

[0036] (Soda-lime glass) SiO2: 65~80% by mass Al2O3: 0~5% by mass CaO: 5~15% by mass MgO: 2% by mass or more NaO: 10~18% by mass K2O: 0~5% by mass MgO+CaO: 5~15% by mass Na2O+K2O: 10~20% by mass SO3:0.05~0.3% by mass B2O3:0~5% by mass Total iron oxide converted to Fe2O3 (T-Fe2O3): 0.02-0.03 mass%

[0037] The thickness of the laminated glass 10 according to the present embodiment is not particularly limited, but the total thickness of the outer glass sheet 11 and the inner glass sheet 12 can be, for example, 2.1 to 6 mm, and from the viewpoint of weight reduction, the total thickness of the outer glass sheet 11 and the inner glass sheet 12 is preferably 2.4 to 3.8 mm, more preferably 2.6 to 3.4 mm, and particularly preferably 2.7 to 3.2 mm. Thus, in order to reduce weight, it is necessary to reduce the total thickness of the outer glass sheet 11 and the inner glass sheet 12. Therefore, the thickness of each glass sheet is not particularly limited, but the thickness of the outer glass sheet 11 and the inner glass sheet 12 can be determined, for example, as follows.

[0038] The outer glass sheet 11 is primarily required to be durable and impact resistant against external obstacles, and as a windshield for an automobile, it is required to have impact resistance against flying objects such as pebbles. On the other hand, the thicker the sheet, the heavier it becomes, which is not preferable. From this viewpoint, the thickness of the outer glass sheet 11 is preferably 1.8 to 2.3 mm, and more preferably 1.9 to 2.1 mm. The thickness to be adopted can be determined according to the application of the glass.

[0039] The thickness of the inner glass sheet 12 can be the same as that of the outer glass sheet 11, but can be made thinner than the outer glass sheet 11, for example, to reduce the weight of the laminated glass 10. Specifically, in consideration of the strength of the glass, the thickness is preferably 0.6 to 2.0 mm, more preferably 0.8 to 1.6 mm, and particularly preferably 1.0 to 1.4 mm. Furthermore, the thickness of the inner glass sheet 12 is preferably 0.8 to 1.3 mm. The thickness to be adopted for the inner glass sheet 12 can be determined depending on the application of the glass.

[0040] Here, an example of a method for measuring the thickness of a curved glass plate (laminated glass) 1 will be described. First, the measurement positions are two points, one above the other, on a center line S that extends vertically through the center of the left-right direction of the glass plate. The measuring device is not particularly limited, but for example, a thickness gauge such as SM-112 manufactured by Techclock Corporation can be used. During measurement, the glass plate is placed so that the curved surface is placed on a flat surface, and the edge of the glass plate is clamped with the thickness gauge to perform measurement. Even when the glass plate is flat, the measurement can be performed in the same way as when it is curved.

[0041] <1-2. Interlayer film> The interlayer film 13 is formed of at least one layer, and as an example, as shown in FIG. 3, it can be formed of three layers, in which a soft core layer 131 is sandwiched between harder outer layers 132. However, the present invention is not limited to this configuration, and it is sufficient that the interlayer film 13 is formed of multiple layers including the core layer 131 and at least one outer layer 132 arranged on the outer glass sheet 11 side. For example, the interlayer film 13 may be a two-layer interlayer film including the core layer 131 and one outer layer 132 arranged on the outer glass sheet 11 side, or an interlayer film 13 in which an even number of outer layers 132 of two or more are arranged on both sides of the core layer 131, or an interlayer film 13 in which an odd number of outer layers 132 are arranged on one side of the core layer 131 and an even number of outer layers 132 are arranged on the other side of the core layer 131. When only one outer layer 132 is provided, it is provided on the outer glass sheet 11 side as described above, and this is for improving the breakage resistance against external forces from outside the vehicle or outdoors. Furthermore, the greater the number of outer layers 132, the higher the sound insulation performance.

[0042] The hardness of the core layer 131 is not particularly limited as long as it is softer than the outer layer 132. The materials constituting the layers 131 and 132 are not particularly limited, but for example, the materials can be selected based on the Young's modulus. Specifically, at a frequency of 100 Hz and a temperature of 20 degrees, the hardness is preferably 1 to 20 MPa, more preferably 1 to 18 MPa, and particularly preferably 1 to 14 MPa. By setting the hardness in this range, it is possible to prevent the sound transmission loss (STL) from decreasing in a low frequency range of about 3500 Hz or less. On the other hand, the Young's modulus of the outer layer 132 is preferably large in order to improve the sound insulation performance in a high frequency range, as described later, and can be 560 MPa or more, 600 MPa or more, 650 MPa or more, 700 MPa or more, 750 MPa or more, 880 MPa or more, or 1300 MPa or more at a frequency of 100 Hz and a temperature of 20 degrees. The upper limit of the Young's modulus of the outer layer 132 is not particularly limited, but can be set, for example, from the viewpoint of processability. For example, it is known from experience that when the strength is 1750 MPa or more, workability, particularly cutting, becomes difficult.

[0043] As a specific material, the outer layer 132 can be made of, for example, polyvinyl butyral resin (PVB). Polyvinyl butyral resin is preferable because it has excellent adhesion to each glass plate and penetration resistance. On the other hand, the core layer 131 can be made of, for example, ethylene vinyl acetate resin (EVA) or polyvinyl acetal resin which is softer than the polyvinyl butyral resin constituting the outer layer. By sandwiching a soft core layer, it is possible to greatly improve the sound insulation performance while maintaining the same adhesion and penetration resistance as a single-layer resin interlayer.

[0044] In general, the hardness of polyvinyl acetal resin can be controlled by (a) the degree of polymerization of polyvinyl alcohol as a starting material, (b) the degree of acetalization, (c) the type of plasticizer, (d) the ratio of the plasticizer added, etc. Therefore, by appropriately adjusting at least one of these conditions, it is possible to produce a hard polyvinyl butyral resin for the outer layer 132 and a soft polyvinyl butyral resin for the core layer 131, even if the same polyvinyl butyral resin is used. Furthermore, the hardness of the polyvinyl acetal resin can be controlled by the type of aldehyde used for acetalization, whether co-acetalization with multiple types of aldehydes or pure acetalization with a single type of aldehyde. Although it cannot be said in general, the polyvinyl acetal resin obtained by using an aldehyde with a larger number of carbon atoms tends to be softer. Therefore, for example, when the outer layer 132 is made of polyvinyl butyral resin, a polyvinyl acetal resin obtained by acetalizing an aldehyde having 5 or more carbon atoms (e.g., n-hexylaldehyde, 2-ethylbutyraldehyde, n-heptylaldehyde, n-octylaldehyde) with polyvinyl alcohol can be used for the core layer 131. However, as long as a predetermined Young's modulus can be obtained, the resin is not limited to the above resins.

[0045] The total thickness of the intermediate film 13 is not particularly limited, but is preferably 0.3 to 6.0 mm, more preferably 0.5 to 4.0 mm, and particularly preferably 0.6 to 2.0 mm. The thickness of the core layer 131 is preferably 0.1 to 2.0 mm, and more preferably 0.1 to 0.6 mm. On the other hand, the thickness of each outer layer 132 is preferably 0.1 to 2.0 mm, and more preferably 0.1 to 1.0 mm. Alternatively, the total thickness of the intermediate film 13 may be constant, and the thickness of the core layer 131 may be adjusted within this range.

[0046] The thicknesses of the core layer 131 and the outer layer 132 can be measured, for example, as follows. First, a cross section of the laminated glass is magnified 175 times and displayed using a microscope (for example, Keyence VH-5500). Then, the thicknesses of the core layer 131 and the outer layer 132 are identified and measured by visual inspection. At this time, in order to eliminate variations due to visual inspection, the measurement is performed five times, and the average values ​​are taken as the thicknesses of the core layer 131 and the outer layer 132. For example, an enlarged photograph of the cross section of the laminated glass is taken, and the core layer and the outer layer 132 are identified in the photograph and their thicknesses are measured.

[0047] The thickness of the core layer 131 and the outer layer 132 of the interlayer 13 does not need to be constant over the entire surface, and may be wedge-shaped for laminated glass used in a head-up display, for example. In this case, the thickness of the core layer 131 and the outer layer 132 of the interlayer 13 is measured at the thinnest part, that is, the bottom edge part of the laminated glass. When the interlayer 13 is wedge-shaped, the outer glass sheet and the inner glass sheet are not arranged parallel to each other, but such an arrangement is also included in the glass sheet of the present invention. That is, the present invention includes an arrangement of the outer glass sheet and the inner glass sheet when using an interlayer 13 using a core layer 131 or an outer layer 132 whose thickness increases at a rate of change of 3 mm or less per meter.

[0048] The method for producing the intermediate film 13 is not particularly limited, but examples thereof include a method in which a resin component such as the above-mentioned polyvinyl acetal resin, a plasticizer, and other additives as necessary are blended and kneaded uniformly, and then each layer is extruded at once, and a method in which two or more resin films produced by this method are laminated by a pressing method, a lamination method, etc. The resin film before lamination used in the lamination method by a pressing method, a lamination method, etc. may have a single layer structure or a multilayer structure. In addition to being formed of multiple layers as described above, the intermediate film 13 can also be formed of a single layer.

[0049] <2. Overview of the shielding layer> Next, the shielding layer 4 will be described. As shown in Fig. 1, the shielding layer 4 includes a peripheral portion 41 laminated along the entire periphery of the inner glass plate 12, and a rectangular extension portion 42 connected to the peripheral portion 41 and extending downward from near the center of the upper side of the inner glass plate 12. A trapezoidal opening 43 is formed at the lower end of the extension portion 42, and the imaging device 2 attached to the inside of the vehicle can capture images of the outside of the vehicle through the opening 43 and the laminated glass 10.

[0050] 2, the bracket 6 described above is fixed onto the shielding layer 4. Specifically, the bracket 6 is formed into a frame shape surrounding the opening, and is fixed to the shielding layer 4 with double-sided tape, adhesive, or the like. The photographing device 2 is supported on the bracket 6, and is configured to photograph the outside of the vehicle through the opening 43. Although not shown in the figure, a cover is attached to the bracket 6 so that the photographing device 2 is not visible from inside the vehicle.

[0051] Next, a description will be given of the material of the shielding layer 4. The material of the shielding layer 4 may be appropriately selected depending on the embodiment as long as it can block the view from outside the vehicle, and for example, a ceramic of a dark color such as black, brown, gray, or dark blue may be used.

[0052] When black ceramic is selected as the material for the shielding layer 4, for example, black ceramic is laminated on the inner surface of the inner glass plate 12 and the inner surface of the outer glass plate 11 by screen printing or the like, and the laminated ceramic is heated together with the glass plates 11, 12. When the ceramic hardens, the shielding layer 4 is completed. Note that various materials can be used as the ceramic for each shielding layer 4. For example, ceramic having the composition shown in Table 1 below can be used for the shielding layer 4.

[0053] [Table 1] *1, Main components: copper oxide, chromium oxide, iron oxide and manganese oxide *2, Main ingredients: bismuth borosilicate, zinc borosilicate

[0054] <3. In-vehicle systems> Next, an in-vehicle system including an image capturing device 2 and an image processing device 3 will be described with reference to Fig. 2 and Fig. 3. Fig. 3 illustrates the configuration of the in-vehicle system. As illustrated in Fig. 3, the in-vehicle system according to this embodiment includes the image capturing device 2 and an image processing device 3 connected to the image capturing device 2.

[0055] The image processing device 3 is a device that processes the captured image acquired by the photographing device 2. The image processing device 3 has, for example, general hardware such as a storage unit 31, a control unit 32, and an input / output unit 33 connected by a bus as a hardware configuration. However, the hardware configuration of the image processing device 3 is not limited to this example, and components can be added, omitted, or added as appropriate to the specific hardware configuration of the image processing device 3 depending on the embodiment.

[0056] The storage unit 31 stores various data and programs (not shown) used in the processes executed by the control unit 32. The storage unit 31 may be realized, for example, by a hard disk or a recording medium such as a USB memory. The various data and programs stored in the storage unit 31 may be acquired from a recording medium such as a CD (Compact Disc) or a DVD (Digital Versatile Disc). Furthermore, the storage unit 31 may be called an auxiliary storage device.

[0057] As described above, the laminated glass 10 is disposed at an angle with respect to the vertical direction and is curved. The image capturing device 2 captures the situation outside the vehicle through the laminated glass 10. Therefore, the captured image captured by the image capturing device 2 is deformed according to the attitude, shape, refractive index, optical defects, etc. of the laminated glass 10. In addition, aberration inherent to the camera lens of the image capturing device 2 is also added. Therefore, the storage unit 31 may store correction data for correcting the image deformed by the aberration of the laminated glass 10 and the camera lens.

[0058] The control unit 32 has one or more processors such as a microprocessor or a CPU (Central Processing Unit), and peripheral circuits (ROM (Read Only Memory), RAM (Random Access Memory), interface circuits, etc.) used for processing by the processor. The ROM, RAM, etc. may be called main memory devices in the sense that they are arranged in an address space handled by the processor in the control unit 32. The control unit 32 functions as an image processing unit 321 by executing various data and programs stored in the memory unit 31.

[0059] The image processing unit 321 processes the captured image acquired by the image capturing device 2. The processing of the captured image can be appropriately selected according to the embodiment. For example, the image processing unit 321 may recognize the subject appearing in the captured image by analyzing the captured image by pattern matching or the like. In this embodiment, since the image capturing device 2 captures the situation in front of the vehicle, the image processing unit 321 may further determine whether or not a living being such as a human is captured in front of the vehicle based on the subject recognition. If a person is captured in front of the vehicle, the image processing unit 321 may output a warning message by a predetermined method. Also, for example, the image processing unit 321 may perform a predetermined processing process on the captured image. Then, the image processing unit 321 may output the processed captured image to a display device (not shown) such as a display connected to the image processing device 3.

[0060] The input / output unit 33 is one or more interfaces for transmitting and receiving data to and from a device external to the image processing device 3. The input / output unit 33 is, for example, an interface for connecting to a user interface, or an interface such as a Universal Serial Bus (USB). In this embodiment, the image processing device 3 is connected to the photographing device 2 via the input / output unit 33, and acquires an image photographed by the photographing device 2.

[0061] Such an image processing device 3 may be a device designed specifically for the service to be provided, or a general-purpose device such as a PC (Personal Computer) or a tablet terminal.

[0062] The photographing device 2 is attached to the bracket 6 as described above. Therefore, in this state, the attachment of the photographing device 2 to the bracket 6 and the attachment of the bracket to the first shielding layer 4 are adjusted so that the optical axis of the camera lens of the photographing device 2 passes through the opening 43. Also, a cover (not shown) is attached to the bracket 6 so as to cover the photographing device 2. Therefore, the photographing device 2 is disposed in a space surrounded by the laminated glass 10, the bracket, and the cover, and is not visible from the inside of the vehicle, and from the outside of the vehicle, only a part of the photographing device 2 is visible through the opening 43 by the shielding layer 4. The photographing device 2 and the above-mentioned input / output unit 33 are connected by a cable (not shown), which is drawn out from the cover and connected to the image processing device 3 disposed at a predetermined position inside the vehicle.

[0063] <4. Heating wire> As described above, in this embodiment, the image capture device 2 acquires information by irradiating and receiving light through the opening 43 of the shielding layer 4, but if the portion of the inner glass plate 12 corresponding to the opening 43, i.e., the information acquisition area, becomes cloudy, accurate information cannot be acquired. Therefore, in this embodiment, an electric heating wire 8 made of a conductor is provided in the information acquisition area, and an electric current is applied to the electric heating wire 8 to heat it and prevent clouding. There are various wiring methods for such an electric heating wire 8 according to the configuration of the image capture device 2 and the form of the shielding layer 4, so several modes will be described below.

[0064] FIG. 4 shows the heating wire 8 arranged on the inner glass plate. In the figure, the shielding layer 4 is omitted and only the opening 43 is shown, but the heating wire 8 is arranged on the shielding layer 4 except for the part passing through the opening 43. The heating wire 8 is arranged near the upper edge of the inner glass plate 12 and has a pair of rectangular terminal parts 81, 82 to which the positive and negative poles of a power source are connected. Hereinafter, the terminal part connected to the positive pole will be referred to as the first terminal part 81, and the terminal part connected to the negative pole will be referred to as the second terminal part 82. A first wiring part 83 is formed from the first terminal part 81, which extends downward and further extends along one side edge (left side in the figure) of the opening 43 of the shielding layer 4. This first wiring part 83 extends to the vicinity of the lower end of the opening 43. On the other hand, a second wiring part 84 is formed from the second terminal part 82, which extends downward and further extends to the vicinity of the upper end of the other side edge (right side in the figure) of the opening 43.

[0065] The third wiring part 85 is disposed between the lower end of the first wiring part 83 and the lower end of the second wiring part 84. The third wiring part 85 is formed in an S-shape by connecting five linear parts. Here, the parts are referred to as the first, second, third, fourth, and fifth parts 85a to 85e in order from the first wiring part 83 side. Among them, the first, third, and fifth parts 85a, 85c, and 85e are disposed so as to cross the opening 43, and these constitute the main body part of the present invention. Moreover, these first, third, and fifth parts 85a, 85c, and 85e refer to the parts disposed inside the opening 43. Moreover, these three parts 85a, 85c, and 85e are inclined at an angle α of 30 degrees or less with respect to the horizontal direction. This is because, for example, when the outside of the vehicle is photographed with a camera and image processing is performed, if the heating wire 8 extends in the horizontal direction, all pixels on the horizontal scanning line are blocked by the heating wire 8. In addition, because the windshield is installed at an angle, if the heating wire is positioned at an angle of more than 30 degrees to the horizontal, the inclination of the heating wire will be emphasized more, which may hinder the ability to obtain information.

[0066] The second part 85b is configured to connect the first and third parts 85a and 85c, and the fourth part 85d is configured to connect the third and fifth parts 85c and 85e. These second and fourth parts refer to the parts of the third wiring part 85 that are disposed outside the opening 43, and constitute the connecting parts of the present invention. These second and fourth parts 85b and 85d each have a straight part that extends along the edge of the opening 43, and a bent part that is connected to both ends of the straight part and bent toward the inside of the opening 43. In addition, a bent part that is bent toward the inside of the opening 43 is also formed in the part of the lower end of the first wiring part 83 that is connected to the fifth part 85e, and in the part of the lower end of the second wiring part 84 that is connected to the first part 85a. As shown in the enlarged view of Figure 4, the bent portion is composed of a top S1 and two heating wires 8 extending from this top S1. If the distance from the top S1 to the opening 43 in one of the heating wires 8 is defined as D (its position is defined as S2), and the position on the other heating wire 8 that is the distance D from this top S1 is defined as S3, then the area from S2 to S3 is defined as the bent portion.

[0067] As described above, the heating wire 8 is composed of the first terminal portion 81, the first wiring portion 83, the second wiring portion 84, the third wiring portion 85, and the second terminal portion 82, which are connected in series to a power source (voltage is constant). When a current is applied, heat is generated, so that it is possible to prevent fogging from occurring at the opening 43 and also to remove any fogging that occurs.

[0068] The line width of the heating wire 8 is not particularly limited, but the line width of the first, third, and fifth parts 85a, 85c, and 85e arranged inside the opening 43 is preferably 50 to 1000 μm, and more preferably 200 to 500 μm. The part arranged inside the opening 43 is the part visible from outside the vehicle. That is, for example, when the shielding layer 4 is laminated on two surfaces, the surface of the inner glass sheet 12 facing the vehicle interior and the surface of the outer glass sheet 11 facing the vehicle interior, even if the heating wire 8 is arranged in a portion corresponding to the shielding layer 4 on either one of the surfaces, it is preferable that the part visible from outside the vehicle has the line width as described above. Hereinafter, this part may be referred to as an exposed part.

[0069] On the other hand, the second and fourth parts 85b, 85d, the first wiring portion 83, and the second wiring portion 84 disposed outside the opening 43 are preferably 50 to 5000 μm, more preferably 200 to 100 μm, to be hidden by the shielding layer 4. Hereinafter, these portions may be referred to as non-exposed portions.

[0070] The first, third, and fifth parts 85a, 85c, and 85e arranged inside the opening 43 are arranged generally parallel to each other, and the interval between them is preferably 1.2 times or more the width of the first, third, and fifth parts 85a, 85c, and 85e. This point is the same when the heating wires 8 arranged inside the opening 43 are parallel to each other, and when parallel parts are provided inside the opening 43, it is preferable to set the interval as described above.

[0071] The thickness of the heating wire 8 is preferably, for example, 1 to 40 μm, and more preferably 3 to 20 μm. However, the resistance value per unit length of the above-mentioned bent portion is smaller than the resistance value per unit length of the first, third, and fifth parts 85a, 85c, and 85e, thereby suppressing heat generation. As a measure for this, the line width and thickness of the heating wire 8 can be made different in the bent portion from other parts. In the following, measures for suppressing heat generation in the bent portion, including adjustment of the line width and thickness, will be described with reference to FIG. 5. FIG. 5 is an example in which the first to third parts 85a to 85c of the heating wire are extracted, and the bent portion on the lower side of the second part 85b will be described as an example. However, this example of the bent portion can be applied to at least one of the other bent portions.

[0072] <4-1. Bend Part Mode 1> In the embodiment shown in FIG. 5(a), the bent portion 85b2 is provided with a wide portion 85b3 having a line width wider than the other portions of the heating wire 8. The wide portion 85b3 is formed over a predetermined length L in the heating wire extending in two directions from the top of the bent portion 85b2. More specifically, the inner edge of the bent portion 85b2 is formed in a straight line, but a step is formed on the outer edge, thereby forming the wide portion 85b3. By providing a wide portion in the bent portion 85b2 in this manner, the resistance is made smaller than that of the other portions of the heating wire 8, and thus it is possible to suppress the occurrence of localized high heat generation in the bent portion 85b2. The width of the wide portion 85b3 is wider than the width of the other portions of the heating wire 8, and is preferably, for example, 0.05 to 5.0 mm, more preferably 0.3 to 1.0 mm, even more preferably 0.3 to 0.7 mm, and particularly preferably 0.4 to 0.5 mm. Moreover, the width 85b3 of the wide portion is preferably 1.2 times or more, more preferably 1.5 times or more, and particularly preferably 2.0 times or more, the width of the other portions. On the other hand, the width 85b3 of the wide portion is preferably 3 times or less the width of the other portions.

[0073] The length L is not particularly limited, but is preferably 1 to 20 mm, more preferably 5 to 15 mm, and particularly preferably 5 to 10 mm. However, the width and length L of the wide portion 85b3 can be appropriately changed depending on the required resistance. The wide portion 85b3 can be made wider than other portions by providing a step on the inner edge of the bent portion 85b2 or by providing steps on both the outer and inner edges.

[0074] <4-2. Bend section type 2> In the embodiment shown in Fig. 5(b), the width of the bent portion 85b2 becomes wider as it approaches the top of the bent portion 85b2. This configuration also makes the resistance of the bent portion 85b2 smaller than that of other portions of the heating wire 8, thereby making it possible to suppress localized high heat generation. In this case, the width of the bent portion at the widest point and the length L of the portion where the width changes can be set to the values ​​specified in <4-1>.

[0075] <4-3. Mode of bending part 3> In the embodiment shown in Fig. 5(c), a bypass heating wire 85b4 is provided to connect the inner edges of the two heating wires 8 that form the bent portion 85b2. This allows the current flowing through the bent portion to be dispersed to the bypass heating wire 85b4, making it possible to prevent localized high heat generation at the top of the bent portion 85b2. The number of bypass heating wires is not particularly limited, and for example, two bypass heating wires 85b4 and 85b5 may be provided as shown in Fig. 5(d).

[0076] <4-4. Bend section type 4> In the embodiment shown in FIG. 5(e), the width of the bent portion 85b2 is constant, but the thickness is increased in a portion 85b6 of a certain length including the apex, so that the resistance of this portion 85b6 is smaller than that of other portions of the heating wire 8. This makes it possible to suppress localized high heat generation near the apex of the bent portion 85b2. The thickness of this portion is preferably, for example, 1.2 to 40 μm, and more preferably 4.5 to 30 μm. The thickness of this portion is preferably 1.2 times or more the thickness of the other portions, more preferably 1.5 times or more, and particularly preferably 2.0 times or more. However, if the thickness is too large, the amount of ink used for printing will be too large, causing bleeding or reducing the heat suppression effect, so the thickness of this portion is preferably 3 times or less the thickness of the other portions. The length L of the thicker portion can be the same as that shown in <4-1> above.

[0077] <4-5. Bend Part 5> In the embodiment shown in FIG. 5(f), a conductive part 85b7 having an outer diameter larger than the width of the heating wire 8 is provided at the top of the bent part 85b2. In this example, a circular conductive part is formed. This can reduce the resistance at the top of the bent part 85b2. As a result, local high heat generation near the top of the bent part 85b2 can be suppressed. Similarly, a triangular conductive part 85b8 can be formed integrally with the two heating wires that make up the bent part 85b2 between the two heating wires. The shape of the conductive part is not particularly limited, and can be various shapes such as an ellipse, a polygonal shape, and an irregular shape. The maximum outer diameter of the conductive part is not particularly limited, but is preferably 10 mm or less, for example.

[0078] <4-6. Other aspects of the bent portion> In order to reduce heat generation at the bent portion, in addition to the above configuration, the following configuration can also be used. For example, although it depends on the location where the bent portion is formed, it is preferable that the angle θ between the two heating wires extending from the top of the bent portion is large, and can be, for example, 15 degrees or more. This allows the distance between the two heating wires 8 to be large, and heat generation can be suppressed. In addition, although there is no particular upper limit for the angle θ between the two heating wires 8, in order to make the area where the heating wires 8 are wired compact, it is preferable that it is 60 degrees or less, and more preferably 45 degrees or less.

[0079] Also, the bent portion can be formed in an arc shape so as to eliminate sharp parts. In this case, for example, the radius of curvature of the bent portion can be set to 1 to 10 mm. This is because if the radius of curvature of the bent portion is smaller than 1 mm, localized heat generation as described above may occur, while if the radius of curvature is larger than 10 mm, the arc-shaped portion may enter the opening 43, and the portion crossing the opening 43 may not be formed only with straight lines, which may deteriorate the appearance. The radius of curvature is measured at a line passing through the center of the heating wire 8 in the width direction.

[0080] Although the aspects of the bent portion have been described above, at least one of the above-described aspects can be appropriately combined.

[0081] Next, the material and manufacturing method of the heating wire 8 will be described. The heating wire 8 as described above can be made of various materials as long as they are conductive, and for example, silver, copper, etc. can be used. In addition to using silver or copper alone, a laminated structure in which the heating wire 8 is covered with at least one layer of a covering material can also be adopted. For example, when the heating wire 8 is directly laminated on the inner glass plate 12, not on the shielding layer 4, a layer of ceramic with a dark color similar to that of the shielding layer 4 can be placed on the glass plate 1 as a covering material, and the heating wire 8 made of silver can be formed on the covering material. In this way, the silver heating wire 8 cannot be seen from outside the vehicle, so the appearance is improved. In particular, if the ceramic layer and the shielding layer 4 are the same color, there is no sense of incongruity when viewed from outside the vehicle. Furthermore, the heating wire 8 can be sandwiched between covering materials. That is, a three-layer structure can be formed in which a covering material is placed on the glass plate 12, the heating wire 8 is placed on the covering material, and a covering material is further placed so as to cover the heating wire 8. As a result, the heating wire 8 cannot be seen from the inside of the vehicle. In particular, if the silver layer is exposed at the opening 43 through which light passes, it is undesirable because it may cause light reflection or hinder the passage of light. Therefore, if a dark-colored ceramic layer is formed as a covering material on the silver layer, the silver layer will not be visible from the inside of the vehicle. In addition, since the heating wire 8 is disposed on the inside surface of the glass plate 1, a bracket may be attached on the heating wire 8 via an adhesive. In this case, there is a risk that the components of the adhesive may corrode the silver. Therefore, from this viewpoint as well, if the silver is covered with a ceramic layer, it is possible to prevent the silver from being affected by the adhesive.

[0082] Various embodiments are possible for the layer structure including the heating wire 8. For example, the above-mentioned terminal portions 81, 82 can be made of two layers (a ceramic layer and a silver layer laminated in this order from the glass plate side), the wiring portions 83, 84, 85 can be made of three layers (a ceramic layer, a silver layer, and a ceramic layer laminated in this order from the glass plate side), and only the third wiring portion 85 passing through the opening 43 of the shielding layer 4 can be made of only a silver layer. The line width of the covering material is preferably larger than that of the heating wire. Also, the covering material covering the silver layer and the copper layer may be made of a material other than ceramic.

[0083] When arranging the heating wire 8, the shielding layer 4 can be arranged on different sides of the laminated glass as described above. For example, the shielding layer 4 can be formed on the inner surface side of the outer glass sheet 11, and the heating wire can be formed on the inner surface of the inner glass sheet 12. Alternatively, the heating wire 8 can be arranged between the outer glass sheet 11 and the inner glass sheet 12, for example, in the interlayer 13, or so as to be in contact with either one of the glass sheets 11, 12.

[0084] The above-mentioned heating wire 8 can be arranged on the glass plate by various methods. For example, after the inner glass plate 12 (or the outer glass plate 11, the same applies below) is formed, the heating wire 8 can be formed on the inner glass plate 12 by screen printing or the like and fired in the same manner as the shielding layer 4. When the shielding layer 4 is formed on the same surface of the inner glass plate 12, it can be printed together with the shielding layer 4 and fired at the same time. Alternatively, it can be formed on the inner glass plate 12 by transfer printing.

[0085] <5. Windshield manufacturing method> Next, a method for manufacturing a windshield will be described. First, the shielding layer 4 is laminated on the inner glass plate 12 formed into a predetermined shape. Then, these glass plates 11, 12 are formed so as to be curved. This method is not particularly limited, but can be performed, for example, by a known press molding. Alternatively, the outer glass plate 11 and the inner glass plate 12 are placed one on top of the other on a forming mold, and then the forming mold is passed through a heating furnace to be heated. This allows these glass plates 11, 12 to be curved by their own weight.

[0086] After the outer glass sheet 11 and the inner glass sheet 12 are formed in this manner, a laminate is formed in which the interlayer film 13 is sandwiched between the outer glass sheet 11 and the inner glass sheet 12. The interlayer film 13 has a shape larger than the glass sheets 11, 12.

[0087] Next, this laminate is placed in a rubber bag and pre-bonded at about 70 to 110°C while suctioning under reduced pressure. Other methods of pre-bonding are also possible, and the following method can be adopted. For example, the laminate is heated in an oven at 45 to 65°C. Next, the laminate is pressed with a roll at 0.45 to 0.55 MPa. Subsequently, the laminate is heated again in an oven at 80 to 105°C, and then pressed again with a roll at 0.45 to 0.55 MPa. In this way, the pre-bonding is completed.

[0088] Next, the main bonding is performed. The pre-bonded laminate is subjected to the main bonding in an autoclave, for example, at 8 to 15 atmospheres and 100 to 150°C. Specifically, the main bonding can be performed, for example, under conditions of 14 atmospheres and 135°C. Through the above pre-bonding and main bonding, the interlayer film 13 is bonded to each of the glass plates 11, 12. Next, the interlayer film 13 protruding from the outer glass plate 11 and the inner glass plate 12 is cut off.

[0089] Thereafter, the heating wire 8 is formed on the inner surface of the inner glass sheet 12 by the method described above.

[0090] <6. Features> <6-1> The windshield described above provides the following advantages. First, by laminating the heating wire 8 on the opening 43 of the shielding layer 4, fogging of the opening 43 can be prevented. Therefore, when photographing the outside of the vehicle through the opening 43 with the photographing device 2, it is possible to prevent the photographing from being hindered by fogging of the inner glass plate 12 at the opening 43.

[0091] In particular, the upper part of the vehicle interior where the opening 43 of the shielding layer 4 is provided is prone to getting cold and fogging even when the heating is on. Therefore, it is advantageous to have the heating wire 8 laminated in such a position. Also, the opening 43 of the shielding layer 4 where the heating wire 8 is laminated is opposed to the imaging device 2 or surrounded by the bracket 6. This causes a problem that it is difficult for warm air from the heater or defroster to reach the opening 43. Therefore, it is very meaningful to provide an anti-fogging / defrosting function by using an anti-fogging film or the like in the area where warm air is difficult to reach, as described above.

[0092] <6-2> In addition, when local heat generation is likely to occur in a bent portion, it is necessary to control the current value by setting the portion at the upper limit of the heating temperature (for example, 70 to 80°C). This is because heating above the upper limit of the heating temperature may cause the glass plate to crack, resulting in a decrease in production yield. However, if the portion where local heat generation occurs is controlled to be heated at the upper limit of the heating temperature, the heating temperature of other portions may decrease. As a result, there is a problem that the heating wire 8 cannot be controlled to generate sufficient heat overall. Therefore, in this embodiment, the bending portion is configured as in the above-mentioned aspects 1 to 5 so as not to generate local heat. This makes it possible to prevent local heat generation, and therefore the heating wire 8 can also be controlled to generate sufficient heat overall. For example, by adjusting the configuration of the bending portion, the difference between the temperature at the top of the bending portion and the average temperature at two points 35 mm away from the top of the bending portion can be made less than 15 degrees, as shown in the examples described later.

[0093] It is considered that the amount of heat dissipation per unit area of ​​the glass sheet can be suppressed by forming the top of the bent portion into an arc shape, but this limits the shape of the bent portion to an arc shape. Therefore, in this embodiment, even if the bent portion is not formed into an arc shape as described above, the amount of heat dissipation per unit area of ​​the glass sheet can be suppressed by configuring as shown in the above aspects 1 to 5, for example. However, in aspects 1 to 5, if the bent portion is further formed into an arc shape, the amount of heat dissipation can be further suppressed.

[0094] <6-3> In particular, the resistance per unit length of the bent portion in the above embodiment is smaller than the resistance per unit length of the first, third, and fifth parts 85a, 85c, and 85e, thereby suppressing heat generation. Therefore, for example, the bent portion does not need to be formed in an arc shape to suppress heat generation, and even if the bent portion has a sharp corner, heat generation can be suppressed. However, if the bent portion is formed in an arc shape, heat generation can be further suppressed.

[0095] <7. Variations> Although one embodiment of the present invention has been described above, the present invention is not limited to the above embodiment, and various modifications are possible without departing from the spirit of the present invention. The following modified examples can be appropriately combined.

[0096] <7-1> The configuration of the heating wire in the above embodiment is merely an example, and various modifications are possible. That is, the wiring shape and length of the heating wire can be set as appropriate, and the relationship with the opening 43 of the shielding layer 4 can also be set as appropriate, and the opening shape of the shielding layer 4 shown in the above embodiment and the configuration of the heating wire 8 can be combined as appropriate.

[0097] For example, the number of heating wires (corresponding to the main body of the present invention) passing through the opening 43 is not particularly limited, but in order to prevent fogging of the opening, it is preferable to have, for example, 3 to 50. This is because, for example, if there is only one heating wire 8 passing through the opening 43, the fogging cannot be sufficiently removed. Also, if one heating wire 8 is used to sufficiently remove the fogging, it is necessary to increase the temperature of the heating wire 8, but doing so may cause the glass plate to break. Therefore, it is preferable to set the number of heating wires passing through the opening 43 as described above. From the same viewpoint, the total area of ​​the heating wires passing through the opening 43 is 2500 mm 2 More preferably, it is equal to or greater than this.

[0098] <7-2> All the bent portions do not have to be configured to reduce heat generation, and some of the bent portions may be configured as in the above embodiment. In addition, the resistance per unit length of at least one of the second part 85b and the fourth part 85d of the first wiring portion 83, the second wiring portion 84, and the third wiring portion 85, which do not directly contribute to preventing fogging of the glass plate corresponding to the opening 43, can be made smaller than the resistance per unit length of the first part 85a and the third part 85c. In this case, the resistance value can be reduced by widening the line width or increasing the thickness in places other than the bent portions. Alternatively, as shown in FIG. 6, for example, by providing one or more bypass heating wires 85b9 extending in parallel with the straight portion of the second part 85b, the resistance per unit length of the entire second part 85b, that is, the resistance per unit length of the second part 85b can be reduced. Such bypass heating wires 85b9 can be provided in places other than the second part 85b.

[0099] <7-3> Two or more openings can be formed in the shielding layer 4. In this case, for example, as shown in FIG. 7, a heating wire 8 can be arranged in series across two openings 43. In the example of FIG. 7, the heating wire 8 has a wide line width in a portion 89 between two openings 43 to reduce the resistance, thereby reducing heat generation. Similarly, in the example of FIG. 8, parallel heating wires are provided in a portion 89 between two openings 43, thereby reducing the resistance of this portion and reducing heat generation. In this way, when a plurality of openings 43 are provided, the resistance value of the heating wire 8 that is stretched between them can be reduced, and the above-mentioned various methods, such as increasing the thickness, can be applied.

[0100] <7-4> In the above embodiment, the heating wires 8 are formed in series, but they can be configured in a parallel circuit as well. That is, in a parallel circuit, the portion passing through the opening constitutes the main body of the present invention, and the portion outside the opening constitutes a partial connecting portion that connects the main body portions together. Then, the bent portion formed in the connecting portion may be configured as described above.

[0101] <7-5> A part or the whole of the shielding layer 4 may be made of a shielding film that can be attached to a glass plate, thereby blocking the view from outside the vehicle. When attaching the shielding film to the surface of the inner glass plate 12 facing the outside of the vehicle, the attachment may be performed before preliminary adhesion or after main adhesion.

[0102] Furthermore, from the viewpoint of preventing fogging of the passage of light (such as the image of the subject being photographed) during photography on the glass plate, a shielding layer is not necessarily required; it is sufficient that a heating wire 8 is formed in the area through which light passes (information acquisition area).

[0103] <7-6> In the above embodiment, a photographing device is used as the information acquisition device of the present invention, but the present invention is not limited thereto, and various information acquisition devices can be used. That is, as long as the information acquisition device performs light irradiation and / or light reception to acquire information from outside the vehicle, the present invention is not particularly limited. For example, the present invention can be applied to various devices such as a sensor for measuring the distance between vehicles, a visible light and / or infrared camera for measuring the distance between vehicles, a light receiving device for receiving a signal from outside the vehicle such as a light beacon, and a camera using visible light and / or infrared rays for reading white lines on the road as an image. In addition, the number of openings in the shielding layer 4 can be appropriately changed according to the type of the information acquisition device. For example, light irradiation and light reception can be performed through dedicated openings. The information acquisition device may or may not be in contact with the glass plate. In any case, an electric heating wire is formed in the glass plate in the area (information acquisition area) through which the light of the information acquisition device passes. EXAMPLES

[0104] Examples of the present invention will be described below, but the present invention is not limited to the following examples. In the following, Examples 1 to 11 were produced, each having a different structure of the connecting portion of the present invention. FIG. 9A shows the basic structure of Examples 1 to 11, and FIG. 9B shows the structure of the comparative example, with a total length of 140 mm. In the basic structure of Examples 1 to 11 shown in FIG. 9A, a bent portion corresponding to any of the above-mentioned aspects 1 to 5 is provided, but in the structure of the comparative example shown in FIG. 9B, no bent portion like the Examples is provided. The connecting portions of Examples 1 to 11 differ in the line width of the bent portion, the line width of the portion other than the bent portion (hereinafter referred to as the wire end portion), the thickness of the bent portion, the length of the bent portion, the presence or absence of a bypass heating wire, and the presence or absence of a conductive portion. In addition, the apex of the bent portion of each of Examples 1 to 11 and the comparative example is an acute angle (angle θ=45 degrees) and is not formed in an arc shape (radius of curvature is 0). In addition, the thickness of each of the wire ends is 6 μm.

[0105] The connecting parts in Examples 1 to 11 and Comparative Example were all formed by silver printing on square green glass with a thickness of 2 mm and a side length of 125 mm. In addition, square silver-printed application parts with a side length of 10 mm were provided on both ends of each connecting part.

[0106] For the connecting parts of Examples 1 to 11 and Comparative Example, the voltage applied to the application parts was adjusted based on the resistance values ​​measured at both application parts so that the heat generation would be constant. Here, the target heat generation was set to 25 W / m. The heat generation of the entire connecting part was 3.5 W (25 W / m*0.14 m). The voltage application time was set to 5 minutes. The resistance values, the temperatures of the glass plates before application, and the applied voltages in Examples 1 to 11 and Comparative Example are as shown in Table 2 below. [Table 2]

[0107] The specifications of the connecting parts in Examples 1 to 11 and the Comparative Example are as follows. In Examples 1 to 6, the length of the bent part and the width of the wire end are different (see, for example, FIG. 5(a)). In Examples 7 and 8, the thickness of the bent part and the thickness of the wire end are different (see, for example, FIG. 5(e)). In Examples 9 and 10, a bypass heating wire is provided (see, for example, FIG. 5(c)(d)). In Example 11, a circular conductive part of 1 mm is provided (see, for example, FIG. 5(f)). On the other hand, in the Comparative Example, there is no bent part as in the Examples, and the bent part and the wire end are integrated, with the same width and thickness. [Table 3]

[0108] For Examples 1 to 11 and Comparative Example configured as described above, the temperatures of the heating wire were measured at a, b, and c shown in Figures 9A and 9B. b is the top of the bent part, and a and c are points on the connecting part 35 mm away from b. Then, for Examples 1 to 18, the average temperature s of a and c and the temperature difference dT between b and the average temperature s were calculated. The results are as follows: [Table 4]

[0109] According to the above results, in all the examples, the temperature difference dT is less than 15°C. Therefore, in the examples 1 to 11, no localized high temperature occurred in the entire connecting portion, and it was found that an appropriate heating temperature was ensured even in positions (e.g., a, c) away from b, which is the apex of the bent portion where high temperatures are likely to occur. Therefore, it was found that, for example, even when the upper limit of the heating temperature was controlled to be, for example, 70 to 80°C, localized heat generation could be suppressed and the entire connecting portion could be sufficiently heated. On the other hand, in the comparative example, the dT temperature difference exceeded 15°C, and it was found that there was an overall non-uniform tendency.

[0110] As shown in the results of Example 6, when the width of the bent portion is made wider than the width of the wire end and when the length of the bent portion is made longer, the temperature of b can be reduced. Also, as shown in the results of Example 8, when the thickness of the bent portion is made thicker than the thickness of the wire end, the temperature of b can be reduced. Furthermore, as shown in Examples 9 and 10, the provision of a bypass heating wire provides the effect of reducing the temperature of b. [Explanation of symbols]

[0111] 1 Glass plate 2. Imaging device (information acquisition device) 4 Shielding layer 43 Aperture (information acquisition area) 8 Heating wire

Claims

1. A windshield in which an information acquisition device that acquires information from outside the vehicle by irradiating and / or receiving light can be disposed, A glass plate and a heating wire provided on the glass plate and to which an electric current is applied; Equipped with the glass plate has at least one information acquisition area facing the information acquisition device and through which the light passes; The heating wire includes a plurality of linear body portions passing through at least the inside of the information acquisition region, and linear connecting portions connecting the plurality of body portions, the connecting portion has a straight portion disposed along an edge of the information acquisition area and a bent portion connecting the straight portion and a main body portion, The bent portion has an apex and two heating wires extending from the apex, The angle between the heating wires constituting at least one of the bent portions is 15 to 60 degrees, At least one of the connecting parts has a heat generation suppression means for suppressing heat generation when a current is applied thereto, As the heat generation suppression means, a triangular conductive portion is formed integrally with the heating wire between the two heating wires constituting the bent portion. Windshield.

2. A windshield in which an information acquisition device can be disposed that acquires information from outside the vehicle by irradiating and / or receiving light, A glass plate and a heating wire provided on the glass plate and to which an electric current is applied; Equipped with the glass plate has at least one information acquisition area facing the information acquisition device and through which the light passes; The heating wire includes a plurality of linear body portions passing through at least the inside of the information acquisition region, and linear connecting portions connecting the plurality of body portions, the connecting portion has a straight portion disposed along an edge of the information acquisition area and a bent portion connecting the straight portion and a main body portion, The bent portion has an apex and two heating wires extending from the apex, The angle between the heating wires constituting at least one of the bent portions is 15 to 60 degrees, At least one of the connecting parts has a heat generation suppression means for suppressing heat generation when a current is applied thereto, As the heat generation suppression means, at least one of the connecting portions has at least one bypass heating wire that connects the two heating wires that constitute the bent portion.

3. A windshield in which an information acquisition device can be disposed that acquires information from outside the vehicle by irradiating and / or receiving light, A glass plate and a heating wire provided on the glass plate and to which an electric current is applied; Equipped with the glass plate has at least one information acquisition area facing the information acquisition device and through which the light passes; The heating wire includes a plurality of linear body portions passing through at least the inside of the information acquisition region, and linear connecting portions connecting the plurality of body portions, the connecting portion has a straight portion disposed along an edge of the information acquisition area and a bent portion connecting the straight portion and a main body portion, The bent portion has an apex and two heating wires extending from the apex, The angle between the heating wires constituting at least one of the bent portions is 15 to 60 degrees, At least one of the connecting parts has a heat generation suppression means for suppressing heat generation when a current is applied thereto, A windshield, wherein a thickness of at least a portion of the bent portion is greater than a thickness of a portion of the connecting portion other than the bent portion.

4. A windshield in which an information acquisition device can be disposed that acquires information from outside the vehicle by irradiating and / or receiving light, A glass plate and a heating wire provided on the glass plate and to which an electric current is applied; Equipped with the glass plate has at least one information acquisition area facing the information acquisition device and through which the light passes; The heating wire includes a plurality of linear body portions passing through at least the inside of the information acquisition region, and linear connecting portions connecting the plurality of body portions, the connecting portion has a straight portion disposed along an edge of the information acquisition area and a bent portion connecting the straight portion and a main body portion, The bent portion has an apex and two heating wires extending from the apex, The angle between the heating wires constituting at least one of the bent portions is 15 to 60 degrees, At least one of the connecting parts has a heat generation suppression means for suppressing heat generation when a current is applied thereto, A windshield, wherein the thickness of the bent portion is 1.2 times or more the thickness of the portion of the connecting portion other than the bent portion.

5. 5. The windshield according to claim 1, wherein a resistance value per unit length of the bent portion is smaller than a resistance value per unit length of the main body portion.

6. 6. The windshield according to claim 1, wherein the heat generation suppression means comprises a resistance per unit length of the connecting portion that is smaller than a resistance per unit length of the main body portion.

7. The windshield of claim 2 , wherein at least one of the connections has two of the bypass heating wires.

8. 3. The windshield of claim 2, wherein every said connection has two said bypass heating wires.

9. 9. The windshield according to claim 1, wherein a line width of at least a part of the bent portion is wider than a line width of a portion of the connecting portion other than the bent portion.

10. The windshield according to any one of claims 1 to 9, wherein the bent portion has a length of 1 to 20 mm.

11. 11. The windshield according to claim 1, wherein the line width of the bent portion is 1.2 times or more the line width of the portion of the connecting portion other than the bent portion.

12. The windshield according to any one of claims 1 to 11, wherein at least a part of the bent portion has a line width of 0.3 to 1.0 mm.

13. The windshield according to claim 1 , wherein the bent portion is formed in an arc shape.

14. The windshield according to claim 13, wherein the bent portion has a radius of curvature of 1 to 10 mm.

15. 15. The windshield according to claim 1, wherein the bent portion is provided with a conductive portion having an outer diameter larger than a wire width of the heating wire that constitutes the bent portion.

16. The windshield according to claim 15, wherein the conductive portion has a maximum outer diameter of 10 mm or less.

17. A plurality of the main bodies are arranged substantially parallel to each other, 17. The windshield according to claim 1, wherein the spacing between the main body portions is 1.2 times or more the width of the heating wire.

18. The windshield according to any one of claims 1 to 17, wherein the number of the main body portions is 3 to 50.

19. The total area of ​​the plurality of body portions is 2500 mm 2 The windshield according to any one of claims 1 to 18.

20. 20. The windshield according to claim 1, wherein the main body is inclined at an angle α of 30 degrees or less with respect to the horizontal.

21. 21. The windshield according to claim 1, wherein the temperature difference dT defined at the bend is less than 15°C. Here, dT is |b-s|, s is the average temperature of the heating wire at two points 35 mm away from the apex of the bent portion, and b is the temperature of the heating wire at the apex.

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