Vehicle window glass, and method for manufacturing vehicle window glass

Abstract

To provide a vehicle window glass that can achieve both anti-fogging performance and good visibility at a higher level, and a method for manufacturing vehicle window glass. [Solution] The vehicle window glass includes a glass plate for the window of a vehicle and a defogger provided on the glass plate, the defogger having a first bus bar extending in the vertical direction of the glass plate, a second bus bar extending in the vertical direction of the glass plate, a first power supply terminal connected to the first bus bar, a second power supply terminal connected to the second bus bar, a plurality of heating wires connected between the first bus bar and the second bus bar and extending in the left-right direction of the glass plate, and a boost circuit connected to the first power supply terminal and attached to the main surface of the glass plate on the vehicle side, or a boost circuit attached to the first power supply terminal that boosts the power supplied from the vehicle side and outputs it to the first power supply terminal.

Description

[Technical Field]

[0001] This disclosure relates to vehicle window glass and a method for manufacturing vehicle window glass. [Background technology]

[0002] Conventionally, there is a window glass system that includes a window glass attached to a mobile vehicle, a device provided on the window glass and including an organic element made of an organic material, a temperature sensor for detecting the temperature of the window glass, a temperature and humidity sensor for detecting the temperature and humidity inside the vehicle of the mobile vehicle, and a control unit that determines whether the glass temperature exceeds the dew point temperature based on the glass temperature detected by the temperature sensor and the temperature and humidity inside the vehicle detected by the temperature and humidity sensor, and if it is determined that the glass temperature is below the dew point temperature, energizes a heating element, electric heating film, or defroster attached to the window glass, and if the glass temperature detected by the temperature sensor exceeds a predetermined temperature, deenerges the heating element or electric heating film, or turns off the defroster (see, for example, Patent Document 1). [Prior art documents] [Patent Documents]

[0003] [Patent Document 1] International Publication No. 2021 / 117352 [Overview of the Initiative] [Problems that the invention aims to solve]

[0004] By the way, in order to ensure anti-fogging performance using heating elements in a window glass system, one might consider increasing the width of the heating elements, but this creates the problem of obstructing the view.

[0005] Therefore, one aspect of this disclosure aims to provide a vehicle window glass that can achieve both anti-fogging performance and good visibility at a higher level, and a method for manufacturing vehicle window glass. [Means for solving the problem]

[0006] The vehicle window glass of the embodiment of the present disclosure includes a glass plate for a vehicle window and a defogger provided on the glass plate, the defogger having a first bus bar extending in the vertical direction of the glass plate, a second bus bar extending in the vertical direction of the glass plate, a first power supply terminal connected to the first bus bar, a second power supply terminal connected to the second bus bar, a plurality of heating wires connected between the first bus bar and the second bus bar and extending in the left-right direction of the glass plate, and a boost circuit connected to the first power supply terminal and attached to the main surface of the glass plate on the vehicle side, or a boost circuit attached to the first power supply terminal that boosts the power supplied from the vehicle side and outputs it to the first power supply terminal. [Effects of the Invention]

[0007] According to this disclosure, it is possible to provide a vehicle window glass that can achieve both anti-fogging performance and good visibility at a higher level, as well as a method for manufacturing vehicle window glass. [Brief explanation of the drawing]

[0008] [Figure 1] This is a plan view showing an example of the configuration of a vehicle window glass according to the embodiment, as seen from the inside of the vehicle. [Figure 2A] This figure shows an example of the configuration of the power supply terminal 135RL provided on the second busbar 130RL. [Figure 2B] This figure shows an example of the configuration of the cross-section in the direction of arrow AA in Figure 2A. [Figure 3] This is a magnified view of an example of the configuration surrounding the boost circuit 150 in a vehicle window glass 100. [Figure 4A] This figure shows an example of the configuration of a vehicle window glass 100M1 in a first modified embodiment. [Figure 4B] This figure shows an example of the configuration of a vehicle window glass 100M1 in a first modified embodiment. [Figure 5A]This figure shows an example of the configuration of a vehicle window glass 100M2 in a second modified example of the embodiment. [Figure 5B] This figure shows an example of the configuration of a vehicle window glass 100M2 in a second modified example of the embodiment. [Figure 6] This figure shows an example of the configuration of a vehicle window glass 100M3 in a third modified embodiment. [Modes for carrying out the invention]

[0009] <Embodiment> The following describes the embodiments for implementing this disclosure with reference to the drawings. In each embodiment, deviations in directions such as parallel, perpendicular, horizontal, vertical, up and down, and left and right are permitted to the extent that they do not impair the effects of this disclosure. Unless otherwise specified, the drawings showing glass panels for vehicle windows (hereinafter also referred to as "window glass") show the glass surface of the window glass viewed from the opposite side, and represent the window glass installed in the vehicle from the inside view (in-vehicle view). Furthermore, if the window glass is a windshield installed at the front of the vehicle or a rear window installed at the rear of the vehicle, the vertical direction in the drawings showing the window glass corresponds to the vertical direction of the vehicle, and the left and right direction corresponds to the vehicle width direction. In addition, the window glass is not limited to a windshield or rear window, and may be, for example, a side window installed on the side of the vehicle. In the diagram showing the window glass, the directions parallel to the X-axis (X-axis direction), parallel to the Y-axis (Y-axis direction), and parallel to the Z-axis (Z-axis direction) represent the left-right direction of the glass plate, the up-down direction of the glass plate, and the direction perpendicular to the surface of the glass plate, respectively. The X-axis, Y-axis, and Z-axis directions are mutually orthogonal. Also, a planar view is a view from the XY plane.

[0010] <Vehicle window glass 100> Figure 1 is a plan view showing an example of the configuration of a vehicle window glass 100 from the perspective of the inside of the vehicle. As an example, the vehicle window glass 100 has a symmetrical configuration with respect to a straight line (center line C) that passes through the center in the left-right direction in the vertical direction when viewed from above.

[0011] The vehicle window glass 100 shown in FIG. 1 is an example of a rear glass attached to the rear part of a vehicle. The vehicle window glass 100 includes a glass plate 110 for the vehicle window and a defroster 120 provided on the glass plate 110. The defroster 120 has a first bus bar 130RU, a second bus bar 130RL, power supply terminals 135RU and 135RL, a plurality of heating wires 140, and a booster circuit 150. Since the power supply terminal 135RU is integrally formed with the booster circuit 150, the reference numeral 135RU is shown in parentheses. The power supply terminal 135RU is an example of a first power supply terminal, and the power supply terminal 135RL is an example of a second power supply terminal.

[0012] The first bus bar 130RU, the second bus bar 130RL, and the plurality of heating wires 140 are formed, for example, by printing and baking a paste containing a conductive metal (such as a silver paste etc.) on the main surface 111 on the vehicle interior side of the glass plate 110. As a printing method of the paste containing a conductive metal, a screen printing method, an offset printing method, a gravure printing method, a flexographic printing method, an inkjet printing method, or the like can be used. Also, the first bus bar 130RU, the second bus bar 130RL, and the plurality of heating wires 140 are formed of the same conductive material. Further, the thicknesses of the first bus bar 130RU, the second bus bar 130RL, and the plurality of heating wires 140 formed in this way are substantially the same. Hereinafter, it will be described assuming that the thicknesses of the first bus bar 130RU, the second bus bar 130RL, and the plurality of heating wires 140 are the same.

[0013] The thicknesses of the first bus bar 130RU, the second bus bar 130RL, and the plurality of heating wires 140 may be 5 μm or more and 20 μm or less. Also, the width (line width) of the plurality of heating wires 140 may be 0.15 mm or more and 1.0 mm or less, and may also be 0.15 mm or more and 0.5 mm or less. Hereinafter, the width of the plurality of heating wires 140 shall mean the line width.

[0014] The method for forming the first busbar 130RU, the second busbar 130RL, and the multiple heating elements 140 is not limited to the method described above. For example, the first busbar 130RU, the second busbar 130RL, and the multiple heating elements 140 may be formed by providing a linear or foil-like body containing a conductive material such as copper on the main surface 111 on the interior side or the main surface on the exterior side of the glass plate 110. Alternatively, the first busbar 130RU, the second busbar 130RL, and the multiple heating elements 140 may be attached to the glass plate 110 with an adhesive or the like, or they may be provided inside (inner layer) the glass plate 110 itself.

[0015] Furthermore, the thicknesses of the first busbar 130RU, the second busbar 130RL, or multiple heating elements 140 may be different. If the thicknesses of the first busbar 130RU and the second busbar 130RL are different, the resistance value per unit length should be set taking the thickness into consideration.

[0016] <Outline of the arrangement of the first busbar 130RU, the second busbar 130RL, and multiple heating elements 140, and how to achieve a higher level of balance between ensuring anti-fogging performance and ensuring good visibility> The first busbar 130RU and the second busbar 130RL extend vertically, for example, on the right end of the anti-fogging area 113 of the glass plate 110. The positions of the first busbar 130RU and the second busbar 130RL in the left-right direction of the glass plate 110 are approximately equal, with the first busbar 130RU located above the second busbar 130RL. The vertical lengths of the first busbar 130RU and the second busbar 130RL are approximately equal.

[0017] Multiple heating elements 140 extend in the left-right direction of the glass plate 110. Six heating elements 140 connected to the first busbar 130RU are folded back to the right at the left end of the anti-fogging area 113 and extend to the second busbar 130RL. The six heating elements 140 extend between the first busbar 130RU and the second busbar 130RL without intersecting each other.

[0018] Thus, the six heating wires 140 extending between the first busbar 130RU and the second busbar 130RL are folded back to the right at the left end of the anti-fogging area 113, resulting in 12 heating wires 140 extending in the left-right direction within the anti-fogging area 113. For this reason, in the following explanation, we will assume that 12 heating wires 140 extend in the left-right direction within the anti-fogging area 113 as an example. The 12 heating wires 140 are provided at approximately equal intervals in the vertical direction within the anti-fogging area 113.

[0019] Here, as an example, a configuration is described in which the first busbar 130RU and the second busbar 130RL are provided on the right end side of the anti-fogging region 113 of the glass plate 110, and the multiple heating elements 140 are folded back to the right at the left end side of the anti-fogging region 113. However, the first busbar 130RU and the second busbar 130RL may be provided on the left end side of the anti-fogging region 113 of the glass plate 110, and the multiple heating elements 140 may be folded back to the left at the right end side of the anti-fogging region 113.

[0020] Thus, in a vehicle window glass 100 in which multiple heating elements 140 are folded back at the left-right edges of the glass plate 110, the heating elements 140 become long. Here, when the heating elements 140 are long, it is conceivable to increase the current by increasing the width of the elements to ensure the desired anti-fogging performance, but from the standpoint of ensuring good visibility, there are limits to how wide the heating elements 140 can be made.

[0021] Therefore, when multiple heating elements 140 are long, it becomes necessary to increase the voltage applied to the multiple heating elements 140 in order to ensure good visibility while also ensuring the desired anti-fogging performance.

[0022] Furthermore, in the case of vehicle window glass 100, when the defogger 120 heats up multiple heating elements 140 to remove fogging, it is necessary to equalize the power density of the multiple heating elements 140 in order to heat the glass plate 110 evenly from the viewpoint of ensuring anti-fogging performance.

[0023] The power density of the multiple heating elements 140 refers to the power density of the entire set of heating elements 140. The power density of the multiple heating elements 140 is calculated for the 12 heating elements 140 provided within the anti-fogging region 113 of the glass plate 110, per unit area (m²) of the anti-fogging region 113. 2 This is the power load (W) per square meter, and the unit is W / m². 2 That is the case.

[0024] In order to achieve a higher level of balance between ensuring anti-fogging performance and ensuring good visibility, the vehicle window glass 100 uses a boost circuit 150 to increase the voltage applied to the multiple heating elements 140.

[0025] As an example, a configuration in which multiple heating elements 140 are folded back between the first busbar 130RU and the second busbar 130RL will be described. However, if the length of the multiple heating elements 140 requires a higher applied voltage to ensure the desired anti-fogging performance, the vehicle window glass 100 may have a configuration in which the multiple heating elements 140 extend without being folded back between the busbar at the left end and the busbar at the right end of the glass plate 110. The individual components of the vehicle window glass 100 will be described below.

[0026] <Glass plate 110> The glass plate 110 is an example of a glass plate for a vehicle window. The glass plate 110 may be either single-pane glass or laminated glass. The following description will focus on a configuration in which the glass plate 110 is single-pane glass.

[0027] The outer shape of the glass plate 110 is approximately rectangular. The upper edge 110U represents the upper glass edge of the glass plate 110, and the lower edge 110B represents the lower glass edge of the glass plate 110 (opposite to the upper edge 110U). The left edge 110L represents the left glass edge of the glass plate 110, and the right edge 110R represents the right glass edge of the glass plate 110 (opposite to the left edge 110L). The left edge 110L is the glass edge adjacent to the left of the upper edge 110U and the lower edge 110B, and the right edge 110R is the glass edge adjacent to the right of the upper edge 110U and the lower edge 110B.

[0028] The glass plate 110 has a pair of side edges. The left edge 110L is an example of one of the pair of side edges, and the right edge 110R is an example of the other of the pair of side edges, the second side edge. The connection between the upper edge 110U and the left edge 110L is connected with curvature, but it may also be connected without curvature. The shape of the connections between other edges is similar.

[0029] The glass plate 110 has an anti-fogging region 113 and a shielding layer 115.

[0030] <Anti-fog area 113> The anti-fogging region 113 is, for example, the area of ​​the glass plate 110 excluding a portion of the upper part. The anti-fogging region 113 of the glass plate 110 is a roughly rectangular area of ​​the glass plate 110 in which multiple heating elements 140 are provided, and it is an anti-fogging region in which fogging is removed by the heat generated by the multiple heating elements 140. The anti-fogging region 113 is shown in Figure 1, but is omitted in other figures.

[0031] The anti-fogging region 113 is a roughly rectangular region that extends vertically from the lower edge 110B of the glass plate 110 to just before the upper edge 110U, and horizontally between the left edge 110L and the right edge 110R. For example, the upper end of the anti-fogging region 113 is located about 1 / 5 of the vertical length of the glass plate 110, just before the upper edge 110U.

[0032] The outer edge of the anti-fogging region 113 is located outside the opening 115A of the shielding layer 115 on the lower edge 110B side, outside the opening 115A of the shielding layer 115 on the left edge 110L side and the right edge 110R side, and inside the opening 115A of the shielding layer 115 on the upper edge 110U side.

[0033] Within the anti-fogging area 113, for example, 12 heating elements 140 extend in the left-right direction. In the following, when describing which of the 12 heating elements 140 is the first from the top, it may simply be referred to as the "nth" element.

[0034] A camera for acquiring images of the outside of the vehicle, or a lamp such as a high-mounted stop lamp, may be provided on the interior side of the vehicle window glass 100, but these are omitted here. Furthermore, a through-hole for the wiper pivot (the rotation axis of the wiper) of the wiper may be provided in the vehicle window glass 100, but this is also omitted here.

[0035] If a camera or lamp is installed, the camera or lamp should be positioned within the anti-fogging area 113. This is to ensure a clear view within the camera's imaging range, or to improve the visibility of the lit lamp from outside the glass plate 110. If a wiper is installed, the wiper's wiping area should be positioned within the anti-fogging area 113. In these cases, the position of the heating element 140 can be appropriately changed to match the position of the camera or lamp, or the wiper's wiping area, thereby appropriately changing the position of the anti-fogging area 113.

[0036] <Shielding layer 115> The shielding layer 115 is a frame-shaped layer provided along the outer edge (upper edge 110U, left edge 110L, lower edge 110B, and right edge 110R) of the glass plate 110. The shielding layer 115 has an opening 115A that exposes almost the entire area inside the outer edge of the glass plate 110. The shielding layer 115 may also be provided with protrusions and openings that project inward from the opening edge of the opening 115A to shield around a camera or lamp, and openings to avoid through holes for the wiper pivot (rotation axis of the wiper) of a wiper.

[0037] Specific examples of the shielding layer 115 include ceramics such as a black ceramic layer. The shielding layer 115 is formed by printing a ceramic paste containing black pigment and glass frit onto the main surface 111 on the interior side of the glass plate 110 and firing it. As a printing method for the ceramic paste containing black pigment and glass frit, screen printing, offset printing, gravure printing, flexographic printing, or inkjet printing can be used. When the glass plate 110 is viewed from the outside of the vehicle, the part that overlaps with the shielding layer 115 is not visible from the outside, resulting in a glass plate 110 with an excellent design.

[0038] <Defogger 120> The defogger 120 is an electrically heated conductive pattern that removes condensation from the glass plate 110. Here, in addition to Figure 1, Figures 2A to 3 will be used for explanation. Figure 2A shows an example of the configuration of the power supply terminal 135RL provided on the second busbar 130RL. Figure 2B shows an example of the configuration of the cross section in the direction of arrow AA in Figure 2A. Figure 2B schematically shows an example of a cross-sectional structure including the power supply terminal 135RL. Figure 3 is an enlarged view of an example of the configuration around the boost circuit 150 in the vehicle window glass 100.

[0039] The defogger 120 includes a plurality of heating elements 140 extending in the left-right direction of the glass plate 110, a first busbar 130RU and a second busbar 130RL that supply power to the plurality of heating elements 140, power supply terminals 135RU and 135RL, and a boost circuit 150. The first busbar 130RU and the second busbar 130RL form a pair. The power supply terminal 135RU is configured integrally with the boost circuit 150, for example.

[0040] In this embodiment, six heating wires 140 are provided on the interior side of the glass plate 110, extending in the left-right direction of the glass plate 110 so as to run parallel to each other and folded back at the left end of the anti-fogging area 113, along with a first bus bar 130RU and a second bus bar 130RL connected to the six heating wires 140, power supply terminals 135RU and 135RL, and a boost circuit 150.

[0041] The first busbar 130RU is connected to the power supply terminal 135RU, and the second busbar 130RL is connected to the power supply terminal 135RL. When a voltage is applied between the first busbar 130RU and the second busbar 130RL from the power supply terminals 135RU and 135RL, all the heating elements 140 are energized and generate heat, removing the condensation from the glass plate 110. At the same time, a voltage boosted by the boost circuit 150 is applied to the first busbar 130RU via the power supply terminal 135RU.

[0042] <First busbar 130RU and second busbar 130RL> The first busbar 130RU and the second busbar 130RL are conductor patterns that extend vertically along the right edge 110R of the glass plate 110. As described above, for example, six heating wires 140 are connected between the first busbar 130RU and the second busbar 130RL, and are folded back to the right at the left end of the anti-fog area 113, so that twelve heating wires 140 extend horizontally within the anti-fog area 113. The first busbar 130RU and the second busbar 130RL are located outside the opening 115A of the shielding layer 115 and overlap with the shielding layer 115. That is, the first busbar 130RU and the second busbar 130RL are provided on the interior surface of the shielding layer 115.

[0043] The first busbar 130RU has an upper end 131RU and a lower end 132RU, and extends vertically between the upper end 131RU and the lower end 132RU. The second busbar 130RL has an upper end 131RL and a lower end 132RL, and extends vertically between the upper end 131RL and the lower end 132RL.

[0044] The first busbar 130RU and the second busbar 130RL are connected to power supply terminals 135RU and 135RL, respectively, approximately at their center in the vertical direction. The first busbar 130RU is supplied with DC current from a DC power supply (not shown) of the vehicle via a boost circuit 150 and power supply terminal 135RU, and the second busbar 130RL is supplied with DC current from a DC power supply (not shown) of the vehicle via power supply terminal 135RL.

[0045] <Power supply terminals 135RL, 135RU> Here, we will first explain the power supply terminal 135RL.

[0046] The power supply terminal 135RL is a metal component provided along the right edge 110R of the glass plate 110. The power supply terminal 135RL is, for example, manufactured by bending sheet metal. Examples of sheet metal materials include copper, copper alloys, aluminum, aluminum alloys, and stainless steel. Copper may be oxygen-free copper with tin plating. Alternatively, the power supply terminal 135RL may be a casting, for example. Examples of metal materials used in casting include copper (oxygen-free copper + tin plating), copper alloys, aluminum, and aluminum alloys. Here, as an example, a configuration in which the power supply terminal 135RL is made of sheet metal will be described.

[0047] The power supply terminal 135RL is mounted on the +Z-side surface of the second busbar 130RL.

[0048] The power supply terminal 135RL has a base 135A and a terminal 135B. The power supply terminal 135RL is manufactured, for example, by bending sheet metal. More specifically, for example, a roughly C-shaped shape extending from terminal 135A2 of the base 135A to the tip of terminal 135B and an L-shaped shape extending from terminal 135A1 of the base 135A to the base of terminal 135B are manufactured from a single sheet of metal. The roughly C-shaped shape extending from terminal 135A2 of the base 135A to the tip of terminal 135B and the L-shaped shape extending from terminal 135A1 of the base 135A to the base of terminal 135B may each be manufactured from separate sheet metals. In this case, the two sheet metals constituting the power supply terminal 135RL may be mechanically joined by welding or screwing.

[0049] The base portion 135A is a plate-shaped part that is attached to the surface of the second busbar 130RL, and is provided with terminals 135A1 and 135A2 at both ends. With the power supply terminal 135RL attached to the surface of the second busbar 130RL, terminal 135A1 is located at the +Y direction end of the base portion 135A, and terminal 135A2 is located at the -Y direction end of the base portion 135A. Terminals 135A1 and 135A2 are located at the tips of the legs that are bent toward the -Z direction side (the surface side of the second busbar 130RL) relative to the base portion 135A.

[0050] Terminals 135A1 and 135A2 are configured substantially parallel to the XY plane so as to fit the surface of the second busbar 130RL. The power supply terminal 135RL is attached to the +Z side surface of the second busbar 130RL by joining terminals 135A1 and 135A2 of the base 135A to the surface of the second busbar 130RL with solder or conductive adhesive. For example, as shown in Figure 2B, terminal 135A1 is connected to the +Z side surface of the second busbar 130RL by solder 137. The same applies to terminal 135A2.

[0051] For example, solder containing Sn (tin) and Pb (lead), or lead-free solder containing Sn and Ag (silver), can be used. The conductive adhesive is formed by printing a paste containing a conductive metal (e.g., silver paste) onto terminals 135A1 and 135A2 and baking it on.

[0052] Terminal 135B rises from between terminals 135A1 and 135A2 of the base 135A towards the +Z direction, and its tip is bent towards the -Y direction, for example. The connector at the end of a power cable connected to a DC power supply (not shown) of the vehicle is connected to terminal 135B.

[0053] For example, terminal 135B of power supply terminal 135RU is connected to one terminal of the vehicle's DC power supply (for example, the positive polarity terminal), and terminal 135B of power supply terminal 135RL is connected to the other terminal of the vehicle's DC power supply (for example, the negative polarity terminal).

[0054] The power supply terminal 135RU, like the power supply terminal 135RL, is a metal component provided along the right edge 110R of the glass plate 110, and is made of sheet metal or casting.

[0055] The power supply terminal 135RU has a terminal 135A1 (see Figure 3) similar to terminal 135A1 of power supply terminal 135RL, for example, and terminal 135A1 (see Figure 3) is connected to the first bus bar 130RU. A boost circuit 150 is integrally mounted to the power supply terminal 135RU. The power supply terminal 135RU is mounted on the +Z-side surface of the first bus bar 130RU, similar to how the power supply terminal 135RL is mounted on the +Z-side surface of the second bus bar 130RL. The connector at the end of a power cable connected to a DC power supply (not shown) of the vehicle is connected to the boost circuit 150. DC current is supplied to the power supply terminal 135RU via the boost circuit 150.

[0056] The DC current supplied to power supply terminals 135RU and 135RL is then supplied to all heating elements 140 via the first busbar 130RU and the second busbar 130RL.

[0057] Since terminals 135A1 and 135A2 of the base 135A are connected to the second busbar 130RL, the DC current supplied from the vehicle's DC power supply is supplied to the second busbar 130RL via terminals 135A1 and 135A2. Therefore, the part of the second busbar 130RL to which terminals 135A1 and 135A2 are connected becomes the power supply point.

[0058] Similarly, since terminal 135A1 (see Figure 3) of the power supply terminal 135RU is connected to the first bus bar 130RU, the DC current supplied from the vehicle's DC power supply via the boost circuit 150 is supplied to the first bus bar 130RU via terminal 135A1. For this reason, the part of the first bus bar 130RU to which terminal 135A1 is connected becomes the power supply point.

[0059] The power supply terminals 135RU and 135RL are attached to the surfaces of the first busbar 130RU and the second busbar 130RL on the +Z direction side, approximately at the center of the first busbar 130RU and the second busbar 130RL in the vertical direction. The positions of the power supply terminals 135RU and 135RL in the vertical direction of the glass plate 110 are determined by the structure of the vehicle, etc. Here, as an example, a configuration in which the power supply terminals 135RU and 135RL are provided at the positions shown in Figure 1 will be described.

[0060] Furthermore, although this description focuses on a configuration in which the base 135A of the power supply terminal 135RL has two terminals 135A1 and 135A2, the base 135A may have only one terminal (for example, one of terminals 135A1 and 135A2). Alternatively, the base 135A of the power supply terminal 135RL may have three or more terminals, and these three or more terminals may be bonded to the surface of the second busbar 130RL on the +Z side.

[0061] Furthermore, although a configuration in which the power supply terminal 135RU has terminal 135A1 will be described, the power supply terminal 135RU may have two or more terminals connected to the first busbar 130RU.

[0062] Next, before explaining the heating element 140, we will explain the boost circuit 150.

[0063] <Boost circuit 150> The boost circuit 150 is integrally configured with the power supply terminal 135RU and is connected to the first busbar 130RU via the power supply terminal 135RU. The boost circuit 150 extends in the -Y direction from the power supply terminal 135RU and is located in a position that overlaps with the first busbar 130RU. Since the first busbar 130RU overlaps with the shielding layer 115, the boost circuit 150 also overlaps with the shielding layer 115.

[0064] The boost circuit 150 has a housing 151, a circuit body 152, legs 153, and terminals 154.

[0065] The housing 151 is, for example, a resin housing, and for example, is integrally formed with the power supply terminal 135RU, the leg portion 153, and the terminal 154 by molding. In this way, the boost circuit 150 is integrally formed with the power supply terminal 135RU. The power supply terminal 135RU is attached to the surface of the first bus bar 130RU on the +Z side. The leg portion 153 is also attached to the surface of the first bus bar 130RU on the +Z side. Therefore, the boost circuit 150 is attached to the surface of the first bus bar 130RU on the +Z side via the power supply terminal 135RU and the leg portion 153.

[0066] The first busbar 130RU is provided on the interior surface of the shielding layer 115, and the shielding layer 115 is provided on the interior main surface 111 of the glass plate 110. That is, the boost circuit 150 is attached to the interior main surface 111 of the glass plate 110 via the power supply terminal 135RU, the legs 153, and the shielding layer 115. This is equivalent to the boost circuit 150 being attached to the interior main surface 111 of the glass plate 110.

[0067] The circuit body 152 is, for example, a switching regulator, which boosts the input voltage input to the input terminal to a predetermined voltage value and outputs it from the output terminal. The input terminal of the circuit body 152 is connected to terminal 154. The connector at the end of a power cable connected to a DC power supply (not shown) of the vehicle is connected to terminal 154. The output terminal of the circuit body 152 is connected to power supply terminal 135RU.

[0068] The circuit body 152, which consists of a switching regulator, boosts the input voltage to a predetermined voltage value by driving the switching element using a pulse width modulation method, for example. The switching regulator may be configured to maintain a nearly constant output voltage by controlling the duty cycle in pulse width modulation according to the input voltage. Alternatively, the switching regulator may be configured to switch with a fixed duty cycle so that the output voltage falls within a certain range. In this case, the circuit configuration is simplified because the duty cycle is not controlled.

[0069] The leg portion 153 extends from the housing 151 in the -Z direction at the -Y direction end of the housing 151. The leg portion 153 is made of metal, for example, and can be made of the same metal or casting as the power supply terminal 135RU. The leg portion 153 is not connected to the circuit body 152 in the electrical circuit, but is provided to fix the boost circuit 150 to the first busbar 130RU on the -Y direction side. The leg portion 153 is connected to the +Z direction surface of the first busbar 130RU by solder or the like, similar to the power supply terminal 135RU. The leg portion 153 may also be connected to the output terminal of the circuit body 152 together with the power supply terminal 135RU. In this case, the point where the power supply terminal 135RU and the leg portion 153 are connected to the first busbar 130RU becomes the power supply point.

[0070] Terminal 154, like terminal 135B of power supply terminal 135RL (see Figure 2A), is a terminal to which the connector at the end of a power cable connected to a DC power supply (not shown) of the vehicle is connected. Terminal 154 is connected to one of the terminals of the vehicle's DC power supply (for example, the positive polarity terminal). For example, terminal 154 extends from the -Y direction end of the housing 151 to the +Z direction.

[0071] Because the boost circuit 150 is small and lightweight, it can be mounted on the surface of the first busbar 130RU on the +Z side via the power supply terminal 135RU and the legs 153. Furthermore, because the boost circuit 150 is small, its width in the X direction is narrower than the width in the X direction of the portion of the shielding layer 115 on which the boost circuit 150 is mounted, allowing the vehicle window glass 100 to be hidden by the shielding layer 115 when viewed from the outside of the vehicle. As a result, a vehicle window glass 100 with an excellent design can be obtained.

[0072] <Heat ray 140> The vehicle window glass 100 includes, as an example, six heating elements 140. The six heating elements 140 extend in the left-right direction of the glass plate 110 between the first bus bar 130RU and the second bus bar 130RL, and are folded back to the right at the left end of the anti-fog area 113. As a result, twelve heating elements 140 extend in the left-right direction within the anti-fog area 113. The vertical spacing of the twelve heating elements 140 is approximately equal.

[0073] Each of the six heating elements 140 has an end connected to a first busbar 130RU and an end connected to a second busbar 130RL. Both ends of the six heating elements 140 overlap with the shielding layer 115, and the folded-back portions may or may not overlap with the shielding layer 115.

[0074] Each heating element 140 is required to be relatively narrow in width so as not to obstruct the view. The line width of each heating element 140 is preferably 1 mm or less, and 1 mm or less is one standard for the line width of the heating elements 140. The line width of each heating element 140 is preferably 0.60 mm to 1.00 mm, and more preferably 0.75 mm to 1.00 mm.

[0075] The six heating elements 140 do not intersect in a plan view, but are folded back at the left end of the anti-fogging area 113, and are arranged in a U-shape in a plan view, for example. Therefore, of the 12 heating elements 140 that extend horizontally within the anti-fogging area 113, the 6th and 7th are a single heating element 140, located at the innermost part of the U-shape.

[0076] Of the 12 heating elements 140 extending in the left-right direction within the anti-fogging area 113, the 5th and 8th elements are single heating elements 140, the 4th and 9th elements are single heating elements 140, the 3rd and 10th elements are single heating elements 140, and the 2nd and 11th elements are single heating elements 140.

[0077] Furthermore, of the 12 heating elements 140 extending horizontally within the anti-fogging area 113, the 1st and 12th are single heating elements 140, located on the outermost edge of the U-shape. Here, the heating element 140 located on the outermost edge of the U-shape is designated as heating element No. 1, and the heating element 140 located on the innermost edge of the U-shape is designated as heating element No. 6. In other words, the six heating elements 140 extending from the outermost to the innermost edge of the U-shape are referred to as heating elements No. 1 to No. 6.

[0078] The No. 6 heating element 140, located at the innermost part of the U-shape, is the shortest of the six heating elements 140, while the No. 1 heating element 140, located at the outermost part of the U-shape, is the longest of the six heating elements 140. Therefore, the lengths of the six heating elements 140 increase sequentially from the No. 6 heating element 140 located at the innermost part of the U-shape to the No. 1 heating element 140 located at the outermost part of the U-shape.

[0079] The heating wires 140, which are folded back at the edges of the glass plate 110 in the left-right direction, are longer than the heating wires that extend between the pair of busbars provided at both ends of the glass plate 110 in the left-right direction. Even though the heating wires 140 are longer, it is required that they have the same wire width as the heating wires that extend between the pair of busbars provided at both ends of the glass plate 110 in the left-right direction, and that the same power density be ensured.

[0080] From this perspective, in the vehicle window glass 100, a boost circuit 150 is provided between the power supply terminal 135RU and the connector at the end of the power cable connected to the DC power supply (not shown) of the vehicle, thereby increasing the voltage applied to the six heating elements 140.

[0081] For example, when the DC voltage supplied from the vehicle's power cable connector to the boost circuit 150 is 12V, the output voltage of the boost circuit 150 is preferably 14V or more and 20V or less, and preferably 16V or more and 18V or less. Here, as an example, when the DC voltage supplied from the vehicle's power cable connector to the boost circuit 150 is 12V, the output voltage of the boost circuit 150 is assumed to be 17V.

[0082] <Simulation> The length of the heating element 140 for No. 1 to No. 6 ranges from 2200mm to 1900mm, and the power density is 450W / m². 2 The simulation was performed under the conditions that the thickness of the six heating elements 140, the first busbar 130RU, and the second busbar 130RL were the same, and the DC voltage supplied from the vehicle's power cable connector was 12V.

[0083] The simulation calculated the line width of the six heating elements 140 with and without the boost circuit 150. In the comparison vehicle window glass without the boost circuit 150, the vehicle's power cable connector was directly connected to the power supply terminal 135RU.

[0084] The line widths of the heating elements 140 for No. 1 to No. 6 in the vehicle window glass used for comparison were 2.04 mm, 1.97 mm, 1.89 mm, 1.79 mm, 1.70 mm, and 1.60 mm, respectively, which significantly exceed the standard line width of 1 mm required to ensure good visibility.

[0085] In contrast, the line widths of the heating elements 140 No. 1 to No. 6 in the vehicle window glass 100 of the embodiment were 0.98 mm, 0.97 mm, 0.93 mm, 0.88 mm, 0.84 mm, and 0.79 mm, respectively, all of which fell below the standard line width of 1 mm required to ensure good visibility.

[0086] Furthermore, the simulation results showed that the following relationship can be established when the DC voltage supplied from the vehicle's power cable connector to the boost circuit 150 is 12V, and the output voltage of the boost circuit 150 is between 14V and 20V.

[0087] If the wire width of the multiple heating wires 140 is 1.0 mm or less, the length of the longest heating wire 140 among the multiple heating wires 140 is 2600 mm or less, and the length of the shortest heating wire 140 among the multiple heating wires 140 is 1800 mm or more, then the power density of the multiple heating wires 140 is 400 W / m². 2More than 500W / m 2 It was found that the following conditions could be met.

[0088] The wire width of the multiple heating elements 140 is 1.0 mm or less, ensuring good visibility, and the power density of the multiple heating elements 140 is 400 W / m². 2 More than 500W / m 2 The following conditions ensure good anti-fogging performance. Furthermore, if voltage boosting is not performed, when the length of the heating element 140 exceeds 1500 mm, measures such as increasing the width of the element become necessary, making it difficult to ensure good visibility. In contrast, with vehicle window glass 100, by applying the voltage boosted by the voltage boosting circuit 150 to all heating elements 140, it is possible to achieve both anti-fogging performance and good visibility at a higher level.

[0089] <Effects> The vehicle window glass 100 includes a glass plate 110 for the window of a vehicle and a defogger 120 provided on the glass plate 110. The defogger 120 includes a first bus bar 130RU extending vertically from the glass plate 110, a second bus bar 130RL extending vertically from the glass plate 110, a power supply terminal 135RU connected to the first bus bar 130RU, a power supply terminal 135RL connected to the second bus bar 130RL, a plurality of heating wires 140 connected between the first bus bar 130RU and the second bus bar 130RL and extending horizontally from the glass plate 110, and a boost circuit 150 connected to the power supply terminal 135RU and attached to the main surface of the glass plate 110 on the vehicle side, or a boost circuit 150 attached to the power supply terminal 135RU that boosts the DC voltage supplied from the vehicle side and outputs it to the power supply terminal 135RU. In this way, by applying the voltage boosted by the boost circuit 150 to the multiple heating elements 140, it is possible to achieve both anti-fogging performance and good visibility at a higher level, even when the multiple heating elements 140 are long.

[0090] Therefore, it is possible to provide a vehicle window glass 100 that can achieve both anti-fogging performance and good visibility at a higher level.

[0091] Further, the first bus bar 130RU and the second bus bar 130RL may be provided on one end side of the glass plate 110 in the left-right direction. When the first bus bar 130RU and the second bus bar 130RL are provided on one end side of the glass plate 110 in the left-right direction, the plurality of heating wires 140 may have a long configuration. Thus, even when the plurality of heating wires 140 are long, by applying the voltage boosted by the boosting circuit 150 to the plurality of heating wires 140, it is possible to achieve both anti-fog performance and good visibility in a more advanced dimension. Further, since the first bus bar 130RU and the second bus bar 130RL are provided on one end side of the glass plate 110 in the left-right direction, there is an advantage that power supply to the plurality of heating wires 140 can be performed on one end side of the glass plate 110 in the left-right direction.

[0092] Further, the plurality of heating wires 140 may be folded back at the other end side of the glass plate 110 in the left-right direction between the first bus bar 130RU and the second bus bar 130RL. When the first bus bar 130RU and the second bus bar 130RL are provided on one end side of the glass plate 110 in the left-right direction and the plurality of heating wires 140 are folded back from the other end side to the one end side of the glass plate 110 in the left-right direction, the plurality of heating wires 140 have a long configuration. Thus, even when the plurality of heating wires 140 are long due to being folded back from the other end side to the one end side of the glass plate 110 in the left-right direction, by applying the voltage boosted by the boosting circuit 150 to the plurality of heating wires 140, it is possible to achieve both anti-fog performance and good visibility in a more advanced dimension.

[0093] Further, the line width of the plurality of heating wires 140 is 1.0 mm or less, and the power density in the plurality of heating wires 140 is 400 W / m 2 or more and 500 W / m 2 or less. The length of the longest heating wire 140 among the plurality of heating wires 140 may be 2600 mm or less, and the length of the shortest heating wire 140 among the plurality of heating wires 140 may be 1800 mm or more. Since the line width of the plurality of heating wires 140 is 1.0 mm or less, good visibility can be ensured, and the power density in the plurality of heating wires 140 is 400 W / m 2 or more and 500 W / m 2The following conditions ensure good anti-fogging performance. Therefore, it is possible to provide a vehicle window glass 100 that can achieve both anti-fogging performance and good visibility at a higher level.

[0094] Furthermore, the DC voltage supplied from the vehicle to the boost circuit 150 may be 12V. By boosting the 12V DC voltage supplied from the DC power supply of a typical passenger car or other vehicle, it is possible to provide a vehicle window glass 100 that can achieve a higher level of balance between ensuring anti-fogging performance and ensuring good visibility, even when multiple heating elements 140 are long.

[0095] In the above description, we have described a configuration in which the first busbar 130RU, the second busbar 130RL, the power supply terminal 135RU, the power supply terminal 135RL, and the boost circuit 150 overlap with the shielding layer 115. However, it is also possible to configure the system in which at least a portion of the first busbar 130RU, the second busbar 130RL, the power supply terminal 135RU, the power supply terminal 135RL, and the boost circuit 150 do not overlap with the shielding layer 115.

[0096] <Method for manufacturing vehicle window glass 100> One example of a method for manufacturing a vehicle window glass 100 is a method for manufacturing a vehicle window glass 100 that includes a glass plate 110 for a vehicle window and a defogger 120 provided on the glass plate 110.

[0097] When assembling the defogger 120 to the glass plate 110, a first busbar 130RU and a second busbar 130RL extending in the vertical direction of the glass plate 110, and a plurality of heating wires 140 connected between the first busbar 130RU and the second busbar 130RL and extending in the horizontal direction of the glass plate 110 are formed by printing or etching.

[0098] Then, power supply terminals 135RU and 135RL are connected to the first busbar 130RU and the second busbar 130RL, respectively, and a boost circuit 150 that increases the DC voltage supplied from the vehicle is connected to power supply terminal 135RU and attached to the main surface of the glass plate 110 on the vehicle side. With this, the vehicle window glass 100 is completed.

[0099] Furthermore, if the boost circuit 150 is not attached to the main surface on the interior side of the glass plate 110, but is instead attached to, for example, the power supply terminal 135RU, then the boost circuit 150 should be attached to the power supply terminal 135RU during the process of installing the boost circuit 150.

[0100] <First variation> Figures 4A and 4B show an example of the configuration of a vehicle window glass 100M1 of a first modified embodiment. As shown in Figures 4A and 4B, the vehicle window glass 100M1 differs from the vehicle window glass 100 in that the boost circuit 150M1 is configured to be insertable and removable from the power supply terminal 135RU. In addition, the power supply terminal 135RU of the vehicle window glass 100M1 has the same configuration as the power supply terminal 135RL shown in Figure 2A.

[0101] Figures 4A and 4B show the parts corresponding to Figure 3. Figure 4A shows an example of the boost circuit 150M1 being plugged into the power supply terminal 135RU, and Figure 4B shows an example of the boost circuit 150M1 being unplugged from the power supply terminal 135RU. Figure 4B also shows the entire power supply terminal 135RU. The power supply terminal 135RU shown in Figure 4B has the same configuration as the power supply terminal 135RL shown in Figure 2A.

[0102] The boost circuit 150M1 differs from the boost circuit 150 shown in Figures 1 and 3 in that the output terminals of the circuit body 152 are configured to be insertable into and removeable from the power supply terminal 135RU. The boost circuit 150M1 does not have legs 153 (see Figure 3). The boost circuit 150M1 is attached to the power supply terminal 135RU by inserting the output terminals of the circuit body 152 into the power supply terminal 135RU.

[0103] Terminal 154 of the boost circuit 150M1 is connected to the input terminal of the circuit body 152. The connector at the end of a power cable connected to a DC power supply (not shown) of the vehicle is connected to terminal 154.

[0104] In the vehicle window glass 100M1, by applying the voltage boosted by the boost circuit 150M1 to multiple heating elements 140, it is possible to achieve a higher level of balance between ensuring anti-fogging performance and ensuring good visibility, even when the multiple heating elements 140 are long.

[0105] Therefore, it is possible to provide a vehicle window glass 100M1 that can achieve both anti-fogging performance and good visibility at a higher level. In addition, the boost circuit 150M1 is easy to install because it can be inserted into and removed from the power supply terminal 135RU.

[0106] In the first modified example, a configuration was described in which the first busbar 130RU, the second busbar 130RL, the power supply terminal 135RU, the power supply terminal 135RL, and the boost circuit 150M1 overlap with the shielding layer 115. However, a configuration in which at least a portion of the first busbar 130RU, the second busbar 130RL, the power supply terminal 135RU, the power supply terminal 135RL, and the boost circuit 150M1 do not overlap with the shielding layer 115 is also possible.

[0107] <Second variation> Figures 5A and 5B show an example of the configuration of a vehicle window glass 100M2 in a second modified embodiment. As shown in Figures 5A and 5B, the vehicle window glass 100M2 differs from the vehicle window glass 100 in that the cable 155 of the boost circuit 150M2 is configured to be insertable and detachable from the power supply terminal 135RU, and the boost circuit 150M2 itself is bonded to the vehicle-side surface of the shielding layer 115 with urethane adhesive or double-sided tape. The boost circuit 150M2 does not have legs 153 (see Figure 3). In addition, the power supply terminal 135RU of the vehicle window glass 100M2 has the same configuration as the power supply terminal 135RL shown in Figure 2A.

[0108] Figures 5A and 5B show the parts corresponding to Figure 3. Figure 5A shows an example where the boost circuit 150M2 is attached to the interior surface of the shielding layer 115, and the connector 155A at the end of the cable 155 is plugged into the terminal 135B of the power supply terminal 135RU. Figure 5B shows an example where the boost circuit 150M2 is attached to the interior surface of the shielding layer 115, and the connector 155A at the end of the cable 155 is pulled out from the power supply terminal 135RU.

[0109] The housing 151 of the boost circuit 150M2 is bonded to the interior surface of the shielding layer 115 with urethane adhesive or double-sided tape. That is, the boost circuit 150M2 is provided on the interior surface of the shielding layer 115. Since the shielding layer 115 is provided on the interior main surface 111 of the glass plate 110, the boost circuit 150M2 is attached to the interior main surface 111 of the glass plate 110 via the shielding layer 115. This is equivalent to the boost circuit 150M2 being attached to the interior main surface 111 of the glass plate 110.

[0110] The output terminal of the circuit body 152 of the boost circuit 150M2 is connected to the cable 155. The output terminal of the circuit body 152 is connected to the power supply terminal 135RU via the cable 155. The cable 155 extends outside the housing 151 and has a connector 155A at its end. Terminal 154 of the boost circuit 150M2 is connected to the input terminal of the circuit body 152, and the connector at the end of a power cable connected to a DC power supply (not shown) of the vehicle is connected to terminal 154.

[0111] The boost circuit 150M2 boosts the input voltage of the circuit body 152 and outputs it from the output terminal of the circuit body 152 to the power supply terminal 135RU via the cable 155.

[0112] In the vehicle window glass 100M2, by applying the voltage boosted by the boost circuit 150M2 to multiple heating elements 140, it is possible to achieve a higher level of balance between ensuring anti-fogging performance and ensuring good visibility, even when the multiple heating elements 140 are long.

[0113] Therefore, it is possible to provide a vehicle window glass 100M2 that can achieve both anti-fogging performance and good visibility at a higher level. In addition, the cable 155 of the boost circuit 150M2 can be inserted into and removed from the power supply terminal 135RU, and the boost circuit 150M2 can be fixed by adhering it to the interior surface of the shielding layer 115, making installation easy.

[0114] In the second modified example, a configuration was described in which the first busbar 130RU, the second busbar 130RL, the power supply terminal 135RU, the power supply terminal 135RL, and the boost circuit 150M2 overlap with the shielding layer 115. However, it is also possible to have a configuration in which at least a portion of the first busbar 130RU, the second busbar 130RL, the power supply terminal 135RU, the power supply terminal 135RL, and the boost circuit 150M2 do not overlap with the shielding layer 115.

[0115] <Third variation> Figure 6 shows an example of the configuration of a vehicle window glass 100M3 of a third modified embodiment. The defogger 120 of the vehicle window glass 100M3 differs from the vehicle window glass 100 shown in Figures 1 and 3 in that it has a third bus bar 130L on the left side of the glass plate 110.

[0116] The third busbar 130L is, for example, composed of a conductor pattern extending vertically on the left end side of the anti-fogging region 113 of the glass plate 110. The third busbar 130L has an upper end 131L and a lower end 132L, and extends vertically between the upper end 131L and the lower end 132L. The vertical position of the upper end 131L is approximately equal to the position of the upper end 131RU of the first busbar 130RU, and the vertical position of the lower end 132L is approximately equal to the position of the lower end 132RL of the second busbar 130RL.

[0117] The third busbar 130L does not have a power supply terminal. The third busbar 130L is installed by being inserted in the middle of the multiple heating wires 140 that connect the first busbar 130RU and the second busbar 130RL shown in Figures 1 and 3. In other words, the third busbar 130L is installed by connecting the multiple heating wires 140 shown in Figures 1 and 3 at the left end, which is the other end of the glass plate 110 in the left-right direction.

[0118] The third busbar 130L, like the first busbar 130RU, the second busbar 130RL, and the multiple heating elements 140, is formed by printing and baking a paste containing a conductive metal (e.g., silver paste) onto the main surface 111 on the interior side of the glass plate 110. The method for printing the paste containing the conductive metal is the same as the method described for the first busbar 130RU, the second busbar 130RL, and the multiple heating elements 140, and the conductive metal is also the same.

[0119] Furthermore, the thickness of the third busbar 130L is, for example, the same as the thickness of the first busbar 130RU, the second busbar 130RL, and the multiple heating elements 140. However, the thickness of the third busbar 130L may differ from the thickness of the first busbar 130RU, the second busbar 130RL, or the multiple heating elements 140.

[0120] The third bus bar 130L is located outside the opening 115A of the shielding layer 115 and overlaps with the shielding layer 115. In other words, the third bus bar 130L is provided on the interior surface of the shielding layer 115.

[0121] In the vehicle window glass 100M3, the multiple heating elements 140 include multiple heating elements 140A extending in the left-right direction of the glass plate 110 between the first bus bar 130RU and the third bus bar 130L, and multiple heating elements 140B extending in the left-right direction of the glass plate 110 between the second bus bar 130RL and the third bus bar 130L. The lengths of all heating elements 140A and 140B are approximately equal. Heating element 140A is an example of a first heating element, and heating element 140B is an example of a second heating element.

[0122] As an example, six heating elements 140A and 140B are provided. In the following, in vehicle window glass 100M3, unless otherwise specified, heating elements 140A and 140B will simply be referred to as heating element 140. The number of heating elements 140A and 140B may differ.

[0123] In this way, by providing a third busbar 130L between the multiple heating elements 140A and the multiple heating elements 140B, the resistance value of the multiple heating elements 140 between the first busbar 130RU and the second busbar 130RL can be reduced compared to the multiple heating elements 140 of the vehicle window glass 100 without the third busbar 130L, as shown in Figures 1 and 3. For this reason, the voltage boosted by the boost circuit 150 may be slightly lower compared to the vehicle window glass 100 shown in Figures 1 and 3.

[0124] In a vehicle window glass 100M3 including a third busbar 130L, the output voltage of the boost circuit 150 is applied from the power supply terminal 135RU to the multiple heating elements 140A via the first busbar 130RU. The DC current flowing through the multiple heating elements 140A flows through the third busbar 130L to the multiple heating elements 140B and back to the second busbar 130RL.

[0125] By applying the voltage boosted by the boost circuit 150 to the multiple heating elements 140, the vehicle window glass 100M3, including the third busbar 130L, can achieve a higher level of balance between anti-fogging performance and good visibility.

[0126] Furthermore, when the output voltage of the boost circuit 150 is 14V or higher and 20V or lower, the wire width of the multiple heating elements 140A and 140B is 1.0 mm or less, and the power density of the multiple heating elements 140A and 140B is 400 W / m 2 More than 500W / m 2The length of the longest heating element 140 among the multiple heating elements 140A and 140B may be 900 mm or more and 1400 mm or less. It is even more preferable that the length of the longest heating element 140 is 1000 mm or more. It is even more preferable that the length of the longest heating element 140 is 1300 mm or less.

[0127] The wire width of the multiple heating elements 140 is 1.0 mm or less, ensuring good visibility, and the power density of the multiple heating elements 140 is 400 W / m². 2 More than 500W / m 2 The following conditions ensure good anti-fogging performance. Therefore, we can provide vehicle window glass 100M3 that can achieve a higher level of balance between ensuring anti-fogging performance and ensuring good visibility.

[0128] In the third modified example, a configuration was described in which the first busbar 130RU, the second busbar 130RL, the third busbar 130L, the power supply terminal 135RU, the power supply terminal 135RL, and the boost circuit 150 overlap with the shielding layer 115. However, it is also possible to have a configuration in which at least a portion of the first busbar 130RU, the second busbar 130RL, the third busbar 130L, the power supply terminal 135RU, the power supply terminal 135RL, and the boost circuit 150 do not overlap with the shielding layer 115.

[0129] Although exemplary vehicle window glass and methods for manufacturing vehicle window glass have been described above, this disclosure is not limited to the specifically disclosed embodiments, and various modifications and changes are possible without departing from the scope of the claims. [Explanation of Symbols]

[0130] Vehicle window glass for 100, 100M1, 100M2, and 100M3 models. 110 Glass plate 110B Lower edge 110L left edge 110R right edge 110U upper edge 111 Main surface 113 Anti-fog area 115 Shielding layer 115A opening 120 Defogger 130RU Bus Bar No. 1 130RL 2nd Busbar 130L 3rd bus bar 131RU, 131RL top end 132RU, 132RL bottom end 135RU, 135RL power supply terminals 140 Heat wire 140A heating element (an example of the first heating element) 140B Thermal element (an example of a second thermal element) 150, 150M1, 150M2 Boost Circuits 151 cabinets 152 Circuit body 153 Legs 154 terminals 155 Cable 155A connector

Claims

1. Glass panels for vehicle windows, A defogger provided on the glass plate and Includes, The aforementioned defogger is, A first busbar extending vertically in the glass plate, A second busbar extending vertically in the glass plate, A first power supply terminal connected to the first busbar, A second power supply terminal connected to the second busbar, A plurality of heating elements are connected between the first busbar and the second busbar and extend in the left-right direction of the glass plate, A boost circuit connected to the first power supply terminal and attached to the main surface of the glass plate on the vehicle side, or a boost circuit attached to the first power supply terminal that boosts the power supplied from the vehicle side and outputs it to the first power supply terminal. Vehicle window glass having the following features.

2. The vehicle window glass according to claim 1, wherein the first bus bar and the second bus bar are provided on one end of the glass plate in the left-right direction.

3. The vehicle window glass according to claim 2, wherein the plurality of heating elements are folded back at the other end of the glass plate in the left-right direction between the first busbar and the second busbar.

4. The wire width of the plurality of heating elements is 1.0 mm or less, and the power density of the plurality of heating elements is 400 W / m². ２ More than 500W / m ２ The vehicle window glass according to any one of claims 1 to 3, wherein the length of the longest heating element among the plurality of heating elements is 2,600 mm or less, and the length of the shortest heating element among the plurality of heating elements is 1,800 mm or more.

5. The vehicle window glass according to claim 4, wherein the DC voltage supplied from the vehicle to the boost circuit is 12V.

6. The defogger further includes a third busbar provided on the other end of the glass plate in the left-right direction, The aforementioned multiple heating elements are A plurality of first heating elements connecting the first busbar and the third busbar, A plurality of second heating elements connecting the second busbar and the third busbar A vehicle window glass according to claim 2, comprising:

7. The wire width of the plurality of first heating wires and the plurality of second heating wires is 1.0 mm or less, and the power density of the plurality of first heating wires and the plurality of second heating wires is 400 W / m². ２ More than 500W / m ２ The vehicle window glass according to claim 6, wherein the length of the longest heating element among the plurality of first heating elements and the plurality of second heating elements is 900 mm or more and 1400 mm or less.

8. Glass panels for vehicle windows, A defogger provided on the glass plate and A method for manufacturing vehicle window glass, including: When assembling the defogger to the glass plate, First busbars and second busbars extending vertically across the glass plate, and a plurality of heating wires connected between the first busbars and the second busbars and extending horizontally across the glass plate are formed by printing or etching. The first busbar and the second busbar are connected to the first power supply terminal and the second power supply terminal, respectively. A method for manufacturing a vehicle window glass, comprising connecting a boost circuit that increases the DC voltage supplied from the vehicle to the first power supply terminal and attaching it to the main surface of the glass plate on the vehicle side, or attaching the boost circuit to the first power supply terminal.

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