Vehicle window glass device

Abstract

The present invention provides a vehicle window glass device that allows an antenna capable of ensuring antenna gain in a predetermined frequency band to coexist with a heated area. [Solution] The vehicle window glass device 300 comprises a vehicle glass plate 1, a first bus bar 3 provided on the glass plate and including upper portions 71, 79 extending in a direction along the upper edge of the glass plate, a second bus bar 4 provided on the glass plate and including lower portions 70, 72 extending in a direction along the lower edge 1b of the glass plate, and a transmit / receive antenna 30 arranged in the space near the upper portion. The glass plate has a heated region 2 extending between the upper and lower portions and a non-heated region extending above the upper portion. The heated region is an area where a conductive member 26 is arranged between the first bus bar and the second bus bar, through which a DC current flows vertically when a DC voltage is applied by a power source. The heated region is heated by the heat generated by the conductive member. The antenna has a conductor 37 that is away from the glass plate and facing the glass plate.

Description

Technical Field

[0001] The present disclosure relates to a window glass device for a vehicle.

Background Art

[0002] Conventionally, a vehicle window glass is known that includes a conductive member that heats a glass plate by applying a voltage to a pair of bus bars for anti-fogging and anti-icing, and an antenna provided in the vicinity of a heating region where the conductive member is disposed (see, for example, Patent Documents 1, 2, and 3).

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Patent Document 2

Patent Document 3

Summary of the Invention

Problems to be Solved by the Invention

[0004] However, in a window glass having a heating region where a conductive member for anti-fogging or the like is disposed, depending on the size of the heating region or the like, the region for disposing the antenna on the window glass is narrowed, so it is difficult to secure the antenna gain in a predetermined frequency band.

[0005] The present disclosure provides a vehicle window glass device in which an antenna capable of securing an antenna gain in a predetermined frequency band can coexist with a heating region.

Means for Solving the Problems

[0006] The present disclosure is a glass plate for a vehicle, and a first bus bar provided on the glass plate and including an upper portion extending in a direction along the upper edge of the glass plate A second busbar is provided on the glass plate and includes a lower portion that extends in a direction along the lower edge of the glass plate, It comprises an antenna located in the space near the aforementioned upper portion, which transmits and receives radio waves of a predetermined frequency, The glass plate has a heated region extending between the upper portion and the lower portion, and a non-heated region extending above the upper portion. The heating region is a region where a conductive member is placed between the first busbar and the second busbar, causing a DC voltage to be applied by a power supply, thereby allowing a DC current to flow in the vertical direction. The heating region is then heated by the heat generated by the conductive member. The present invention provides a vehicle window glass device having an antenna that has a conductor that is separated from the glass plate and facing the glass plate. [Effects of the Invention]

[0007] According to this disclosure, it is possible to provide a vehicle window glass device that allows an antenna capable of securing antenna gain in a predetermined frequency band to coexist with a heated area. [Brief explanation of the drawing]

[0008] [Figure 1] This figure shows an example configuration of a vehicle window glass device in the first embodiment, viewed from the inside of the vehicle. [Figure 2] This is a perspective view showing an example of an antenna configuration for transmitting and receiving radio waves in a specified frequency band. [Figure 3] This is a cross-sectional view showing the upper portion of an example of the structure of a vehicle window glass device in the first embodiment. [Figure 4] This figure shows one example (modified) configuration of a vehicle window glass device in the first embodiment, viewed from the inside of the vehicle. [Figure 5] This figure shows an example configuration of a vehicle window glass device in the second embodiment, viewed from the inside of the vehicle. [Figure 6] This is a cross-sectional view showing the upper portion of an example of the structure of a vehicle window glass device in the second embodiment. [Figure 7]This is a front view illustrating multiple linear conductors included in a conductive member on the projection surface where the antenna conductor is projected horizontally onto a glass plate 1. [Figure 8] This is a cross-sectional view showing the upper portion of an example (modified) of the structure of a vehicle window glass device in each embodiment. [Figure 9] This figure shows an example of simulation results for the transmission characteristics of an antenna, based on differences in the horizontal spacing of multiple wire conductors contained in a conductive material. [Modes for carrying out the invention]

[0009] The embodiments of this disclosure will be described below with reference to the drawings. For ease of understanding this disclosure, the scale of the parts in the drawings may differ from that of the actual dimensions. In this specification, deviations in directions such as "parallel," "right angle," "orthogonal," "horizontal," "vertical," "up and down," and "left and right" are permitted to the extent that they do not impair the function and effect of the embodiments. The shape of the corners is not limited to right angles and may be rounded in an arc shape. In this specification, "X-axis direction" and "Y-axis direction" refer to the direction parallel to the X-axis and the direction parallel to the Y-axis, respectively. The X-axis direction and the Y-axis direction are orthogonal to each other. In this specification, "facing each other" is not limited to a configuration in which all parts face each other, but may include a configuration in which some parts face each other.

[0010] In this embodiment, the X-axis direction represents the left-right direction (lateral direction) of the vehicle body, the vehicle width direction, or the horizontal direction (direction parallel to the horizontal plane). The Y-axis direction represents the up-down direction (vertical direction) of the vehicle body, or the vertical direction (direction perpendicular to the horizontal plane).

[0011] In this embodiment, a windshield attached to the front of a vehicle is a suitable example of a vehicle window glass.

[0012] FIG. 1 is a view showing a configuration example of a vehicle window glass device in the first embodiment from the perspective of the inside of the vehicle. The vehicle window glass device 300 shown in FIG. 1 includes a window glass 100 attached to a window frame 66 formed in a vehicle body. The window glass 100 illustrated in FIG. 1 is a windshield attached to the window frame 66 formed at the front portion of the vehicle body.

[0013] The window frame 66 has an upper frame 66a, a lower frame 66b, a left frame 66c, and a right frame 66d so as to form an opening covered by the window glass 100. The upper frame 66a is a window frame portion extending in the X-axis direction on the positive side in the Y-axis direction of the vehicle body, for example, a flange on the ceiling side of the vehicle body. The lower frame 66b is a window frame portion extending in the X-axis direction on the negative side in the Y-axis direction of the vehicle body, for example, a flange on the dash panel side of the vehicle body. The left frame 66c is a window frame portion connecting between the upper frame 66a and the lower frame 66b on the negative side in the X-axis direction of the vehicle body when viewed from inside the vehicle, for example, a flange of an A-pillar on the front left side of the vehicle body when viewed from inside the vehicle. The right frame 66d is a window frame portion connecting between the upper frame 66a and the lower frame 66b on the positive side in the X-axis direction of the vehicle body when viewed from inside the vehicle, for example, a flange of an A-pillar on the front right side of the vehicle body when viewed from inside the vehicle.

[0014] The vehicle window glass device 300 includes a window glass 100 attached to the window frame 66 and an antenna 30 disposed in the space on the inner side of the glass plate 1 of the window glass 100. The window glass 100 includes a glass plate 1, a first bus bar 3, and a second bus bar 4.

[0015] The glass plate 1 is an example of a glass plate for a vehicle. The glass plate 1 is a transparent or translucent plate-shaped dielectric that is attached to the window frame 66. The glass plate 1 has an outer peripheral edge including an upper edge 1a, a lower edge 1b, a left edge 1c, and a right edge 1d. The upper edge 1a is a glass edge that extends in the X-axis direction on the positive side in the Y-axis direction of the vehicle body and is attached to the upper frame 66a. The lower edge 1b is a glass edge that extends in the X-axis direction on the negative side in the Y-axis direction of the vehicle body and is attached to the lower frame 66b. The left edge 1c is a glass edge that connects between the upper edge 1a and the lower edge 1b on the negative side in the X-axis direction of the vehicle body and is attached to the left frame 66c. The right edge 1d is a glass edge that connects between the upper edge 1a and the lower edge 1b on the positive side in the X-axis direction of the vehicle body and is attached to the right frame 66d.

[0016] The glass plate 1 has a main surface 22 and a main surface 12 on the side opposite to the main surface 22. In this example, the main surface 22 is the surface on the vehicle interior side, and the main surface 12 is the surface on the vehicle exterior side.

[0017] The first bus bar 3 is a strip-shaped electrode provided on the glass plate 1. The first bus bar 3 includes upper portions 71, 79 that extend in a direction along the upper edge 1a of the glass plate 1 (for example, a substantially horizontal direction). The first bus bar 3 is conductively connected to one electrode terminal (for example, the negative electrode terminal 402) of the power source 400 mounted on the vehicle.

[0018] The second bus bar 4 is a strip-shaped electrode provided on the glass plate 1. The second bus bar 4 includes lower portions 72, 70 that extend in a direction along the lower edge 1b of the glass plate 1 (for example, a substantially horizontal direction). The second bus bar 4 is conductively connected to the other electrode terminal (for example, the positive electrode terminal 401) of the power source 400 mounted on the vehicle.

[0019] Note that the first bus bar 3 may be conductively connected to the positive electrode terminal 401 of the power source 400, and the second bus bar 4 may be conductively connected to the negative electrode terminal 402 of the power source 400.

[0020] The glass plate 1 has a heating region 2 that extends between the upper portions 71, 79 of the first bus bar 3 and the lower portions 72, 70 of the second bus bar 4. The heating region 2 is the area where the conductive member 26 is placed and is heated by the heat generated by the conductive member 26. The heating region 2 has vertical sides 6a, 6b, which are a pair of sides facing each other in the X-axis direction.

[0021] The conductive member 26 is provided on the glass plate 1 and is located between the upper portions 71, 79 of the first busbar 3 and the lower portions 72, 70 of the second busbar 4. The conductive member 26 is a member that, when a DC voltage is applied between the first busbar 3 and the second busbar 4 by the power supply 400, allows a DC current to flow vertically between the upper portions 71, 79 and the lower portions 72, 70, and generates heat as the DC current flows vertically through the glass plate 1. The heating region 2 is heated by the heat generated by the conductive member 26, which electrically connects the upper portions 71, 79 and the lower portions 72, 70 of the first busbar 3. Heating the heating region 2 enables snow melting, ice melting, and anti-fogging of the heating region 2 and its vicinity on the glass plate 1.

[0022] The conductive member 26 is, for example, a plurality of heating wires that extend in the vertical direction of the glass plate 1 and are spaced apart in the X-axis direction, as shown in a magnified view in Figure 1. The plurality of heating wires are, for example, corrugated linear conductors that extend from the first busbar 3 toward the second busbar 4. The heating wires are formed from, for example, copper, aluminum, chromium, molybdenum, nickel, titanium, palladium, indium, tungsten, gold, platinum, silver, or an alloy containing any or a plurality of these.

[0023] The conductive member 26 may be a transparent or translucent conductive film installed on the inner layer or outer surface of the glass plate 1, a heating wire installed on the inner layer or surface of the glass plate 1, or a silver-based print formed on the surface of the glass plate 1. As the glass plate 1, laminated glass can usually be used, in which a resin interlayer such as PVB (polyvinyl butyral) or EVA (ethylene-vinyl acetate copolymer) is sandwiched between two sheets of glass. Here, "the conductive member 26 is installed on the inner layer of the glass plate 1" means that the conductive member 26 is enclosed within the laminated glass.

[0024] If the conductive member 26 is a conductive film, antimond-doped tin oxide, bismuth-doped tin oxide, or fluorine-doped tin oxide can be used as the material for the conductive film.

[0025] The conductive member 26 may be installed on the inner layer or outer surface of the glass plate 1. The conductive member 26 is placed on the same layer (inner layer or outer surface) as the first bus bar 3 and the second bus bar 4. However, the conductive member 26 may be placed on a different layer from at least one of the first bus bar 3 and the second bus bar 4, as long as an electrical connection to the first bus bar 3 and the second bus bar 4 is ensured via an auxiliary member.

[0026] The heating region 2 on which the conductive member 26 is arranged may be separated into a plurality of heating regions aligned in the X-axis direction. In the example shown in Figure 1, the heating region 2 has two regions aligned in the X-axis direction, namely a first heating region 2a and a second heating region 2b, separated by a gap 9 with the vertical direction of the glass plate 1 as the longitudinal direction. The heating region 2 may have three or more regions. The first heating region 2a has upper edges 6e, 6f that are electrically connected to the upper portion 71 of the first busbar 3, a lower edge 6g that is electrically connected to the lower portion 72 of the second busbar 4, and a pair of vertical edges 6a, 6c that face each other in the X-axis direction. The second heating region 2b has an upper edge 6h that is electrically connected to the upper portion 79 of the first busbar 3, a lower edge 6i that is electrically connected to the lower portion 70 of the second busbar 4, and a pair of vertical edges 6b, 6d that face each other in the X-axis direction.

[0027] In the example shown in Figure 1, the heating region 2 is divided into multiple heating regions, so the first busbar 3 and the second busbar 4 are also divided. The first busbar 3 includes the first upper busbar 3a and the second upper busbar 3b, and the second busbar 4 includes the first lower busbar 4a and the second lower busbar 4b.

[0028] The first busbar 3 may further include vertical portions connected to the upper portions 71 and 79. In the first busbar 3 shown in Figure 1, the first upper busbar 3a includes a vertical portion 73 connected to the upper portion 71, and the second upper busbar 3b includes a vertical portion 76 connected to the upper portion 79. The upper portion 71 is a conductive portion connected to the upper edges 6e and 6f of the first heating region 2a, and the vertical portion 73 is a conductive portion extending away from the vertical edge 6a, which is one side of the first heating region 2a, in a direction along the left edge 1c, which is one side edge of the glass plate 1. The upper portion 79 is a conductive portion connected to the upper edge of the second heating region 2b, and the vertical portion 76 is a conductive portion extending away from the vertical edge 6b, which is one side of the second heating region 2b, in a direction along the right edge 1d, which is the other side edge of the glass plate 1.

[0029] Since the first busbar 3 includes vertical sections 73 and 76 connected to the upper sections 71 and 79, respectively, a portion of the wiring line that electrically connects the upper sections 71 and 79 of the first busbar 3 to the power supply 400 can be provided on the glass panel 1 side rather than on the vehicle body side. This reduces the length of the harness wired to the vehicle body side.

[0030] As shown in Figure 1, the first busbar 3 may further include a horizontal portion 74 connected to the vertical portion 73, and may further include a horizontal portion 77 connected to the vertical portion 76. The horizontal portion 74 is a conductor portion that extends in a direction along the lower edge 1b of the glass plate 1 in a region away from the first heating region 2a. The horizontal portion 77 is a conductor portion that extends in a direction along the lower edge 1b of the glass plate 1 in a region away from the second heating region 2b. The presence of the horizontal portion 74 or the horizontal portion 77 allows for a further reduction in the length of the harness, depending on the position of the terminals of the harness that is wired to the vehicle body.

[0031] In the example shown in Figure 1, the glass plate 1 has multiple electrodes 51, 52, 55, and 56 to which the terminals of multiple harnesses electrically connected to the power supply 400 are electrically connected.

[0032] Electrode 51 is a negative electrode for electrically connecting the terminal of the ground harness 53, which is electrically connected to the negative electrode terminal 402, to the first upper busbar 3a. Electrode 51 is electrically connected to the upper portion 71 of the first busbar 3 via the horizontal portion 74 and the vertical portion 73.

[0033] Electrode 52 is a negative electrode for electrically connecting the terminal of the ground harness 54, which is electrically connected to the negative electrode terminal 402, to the second upper bus bar 3b. Electrode 52 is electrically connected to the upper portion 79 of the first bus bar 3 via the horizontal portion 77 and the vertical portion 76.

[0034] The electrode 55 is a positive electrode for electrically connecting the terminal of the power harness 57, which is electrically connected to the positive terminal 401, to the first lower busbar 4a. The first lower busbar 4a has a connecting busbar 75 which is connected to the lower portion 72 of the second busbar 4. The electrode 55 is electrically connected to the lower portion 72 via the connecting busbar 75.

[0035] Electrode 56 is the positive electrode for electrically connecting the terminal of the power harness 58, which is electrically connected to the positive terminal 401, to the second lower busbar 4b. The second lower busbar 4b has a connecting busbar 78 that is connected to the lower portion 70 of the second busbar 4. Electrode 56 is electrically connected to the lower portion 70 via the connecting busbar 78.

[0036] Antenna 30 transmits and receives (or transmits and receives at least one of) radio waves in a predetermined frequency band F. The radio waves in the predetermined frequency band F may be vertically polarized, horizontally polarized, or circularly polarized. Antenna 30 is formed to transmit and receive radio waves in the high frequency band (e.g., 0.3 GHz to 300 GHz), such as microwaves or millimeter waves. Antenna 30 is suitable as a vehicle antenna if it is capable of transmitting and receiving radio waves including at least one of the 5.8 GHz band and the 5.9 GHz band. Antenna 30 can be applied to, for example, V2X communication systems, 5th generation mobile communication systems, 6th generation mobile communication systems, and in-vehicle radar systems, but the applicable systems are not limited to these. Specific examples of V2X communication systems used in ITS (Intelligent Transport Systems), etc., include vehicle-to-vehicle communication systems (Connected Vehicles Support Systems) and vehicle-to-infrastructure communication systems (e.g., ETC (Electronic Toll Collection) systems).

[0037] The antenna 30 is positioned in the space near the glass plate 1. This makes the antenna gain of the antenna 30 in the frequency band F less susceptible to the influence of the width of the heating region 2. Therefore, an antenna 30 capable of securing an antenna gain in a predetermined frequency band F can coexist with the heating region 2. The antenna 30 is fixed to the main surface 22 of the glass plate 1 or the ceiling of the vehicle compartment via indirect members (not shown), such as brackets and housings, so as to be positioned in the space near the upper portion 71 of the first bus bar 3.

[0038] Furthermore, the antenna 30 has a conductor 37 that is separated from the glass plate 1 and facing the glass plate 1. The conductor 37 may be the ground plane of the antenna 30 or the radiating element of the antenna 30. By having the conductor 37 separated from the glass plate 1 and facing the glass plate 1, the antenna gain of the antenna 30 in the frequency band F becomes less susceptible to the influence of the width of the heating region 2. Therefore, an antenna 30 capable of securing an antenna gain in a predetermined frequency band F can coexist with the heating region 2. In the example shown in Figure 1, the antenna 30 is close to the upper portion 71 of the first bus bar 3 when viewed from inside the vehicle. In particular, the antenna 30 is positioned at a predetermined distance in the positive Y-axis direction from the first upper portion 71a of the first bus bar 3 when viewed from inside the vehicle.

[0039] Figure 2 is a perspective view showing an example of the configuration of an antenna that transmits and receives radio waves in a predetermined frequency band F. The antenna 30 illustrated in Figure 2 is a planar antenna (specifically, a patch antenna) having a dielectric substrate 36 on which a radiating element 38 and a ground plane 39 are formed. The radiating element 38 is a patch element formed on the outer surface of the dielectric substrate 36. The ground plane 39 is a conductor surface formed on the inner surface of the dielectric substrate 36. The shape of the antenna 30 is not limited to the form shown in Figure 2. In the form shown in Figure 2, the conductor 37 shown in Figure 1 may be formed as either a radiating element 38 or a ground plane 39. For example, in the case of the patch antenna shown in Figure 2, the area of ​​the radiating element 38 is often smaller than that of the ground plane 39 in the thickness direction, so it is preferable that the conductor 37 be formed as a radiating element 38.

[0040] Figure 3 is a cross-sectional view showing the upper portion of an example of the structure of a vehicle window glass device in the first embodiment. Reference numeral A indicates the outside of the vehicle, and reference numeral B indicates the inside of the vehicle. When viewed horizontally from the inside of the vehicle, a gap 15 exists between the conductor 37 (radiating element 38 or ground plane 39) and the upper portion 71 of the first busbar 3. Due to the presence of the gap 15, radio waves radiated from or received by the antenna 30 are less likely to be blocked by the upper portion 71 (especially the first upper portion 71a in Figure 1) and the heating region 2, thereby ensuring antenna gain in a predetermined frequency band F.

[0041] The gap 15 is a region that does not include the conductor. For example, the gap 15 is the region enclosed by the horizontal plane 31 passing through the lower end 35 of the conductor 37, the main surface 21 on the outside of the glass plate 1, the horizontal plane 32 passing through the upper end 80 of the upper part 71 of the first busbar 3, and the plane L passing through the lower end 35 and the upper end 80, and is the region sandwiched between the lower edge (lower end 35) of the conductor 37 and the upper edge (upper end 80) of the upper part 71 when viewed horizontally from the inside of the vehicle. The horizontal plane 31 passes through the lower end 14 (lower edge) of the projection surface 13 obtained by projecting the conductor 37 onto the glass plate 1 from the horizontal direction. Plane L is a virtual plane that forms a depression angle (angle θ) with respect to the horizontal plane 31.

[0042] The gap 15 includes the dielectric region of the glass plate 1 and the dielectric region on the vehicle side relative to the glass plate 1. The dielectric region on the vehicle side relative to the glass plate 1 is typically a space where air exists, but it may also be a region containing a dielectric other than air (e.g., resin).

[0043] In the example shown in Figure 1, the antenna 30 is positioned in the space near the upper portion 71 of the first bus bar 3 so as not to overlap with the upper portions 71 and 79 when viewed horizontally from inside the vehicle. More specifically, the antenna 30 is positioned in the space near the upper portion 71 so as to overlap with the unheated region 8, which extends above the upper portions 71 and 79 when viewed horizontally from inside the vehicle. The unheated region 8 is the upper region of the entire area viewed horizontally from inside the vehicle, between the upper frame 66a of the window frame 66 (the upper edge of the opening) and the upper portions 71 and 79 of the first bus bar 3.

[0044] The first heating region 2a includes a first upper edge 6f extending in a direction along the upper edge 1a of the glass plate 1, and a second upper edge 6e extending in a direction along the upper edge 1a, but further away from the upper edge 1a than the first upper edge 6f. The upper portion 71 of the first upper busbar 3a extends along the first upper edge 6f and the second upper edge 6e of the first heating region 2a, respectively. As a result, as shown in Figure 1, a crank portion 7 is formed in the upper portion 71 of the first upper busbar 3a. Due to the formation of the crank portion 7, the non-heating region 8 has a recessed area 81 that is lowered when viewed horizontally from the inside of the vehicle. The projection surface 13 (see Figure 3) overlaps with the recessed area 81. As a result, the antenna 30 can be separated from the upper frame 66a of the window frame 66, so that the radio waves radiated from or received by the antenna 30 are less likely to be blocked by the upper frame 66a of the window frame 66, and thus a wide angle antenna gain can be secured in a predetermined frequency band F.

[0045] The recess 81 may also be a region in the non-heated region 8 that extends upward from the end of the first upper edge 6f side of the first heated region 2a in the crank portion 7, and is bounded by a line segment that reaches the upper frame 66a (upper edge of the opening) of the window frame 66. Alternatively, the recess 81 may be a rectangular region in the non-heated region 8 whose vertical length is the vertical height of the crank portion 7, and whose horizontal length is the sum of the lengths in the X-axis direction of the crank portion 7 and the first upper portion 71a of the first heated region 2a.

[0046] The upper portion 71 of the first bus bar 3 has a crank portion 7, a first upper portion 71a extending from the crank portion 7 toward a vertical portion 76 on one side, and a second upper portion 71b extending from the crank portion 7 toward the gap 9 on the other side.

[0047] The crank portion 7 is formed in a crank shape by having a third upper portion 71c, a first bent portion 91 formed at the connection point between the first upper portion 71a and the third upper portion 71c, and a second bent portion 92 formed at the connection point between the second upper portion 71b and the third upper portion 71c.

[0048] Because the recess 81 is formed in the non-heated region 8, a region 82 other than the recess 81 is formed in the non-heated region 8. This makes the vertical length of the region 82 other than the recess 81 shorter than the vertical length of the recess 81. As a result, the vertical length of the first heated region 2a connected to the second upper portion 71b can be made relatively longer, thereby ensuring the antenna gain of the antenna 30 in a predetermined frequency band F while further suppressing the reduction in the anti-fogging and anti-icing effects of the glass plate 1.

[0049] Furthermore, in the example shown in Figure 1, a crank portion offset in the same direction as the crank portion 7 formed on the upper portion 71 of the first upper busbar 3a is formed on the lower portion 72 of the first lower busbar 4a that faces the crank portion 7. As a result, the vertical length of the first heating region 2a becomes uniform along the X-axis, and the electrical resistance of the conductive member 26 becomes uniform within the first heating region 2a, thereby suppressing localized heating unevenness within the first heating region 2a.

[0050] The recess 81 may be located in the upper central part of the glass plate 1, as shown in the modified example in Figure 4. In the example shown in Figure 4, the first upper edge 6f of the first heating region 2a and the second upper portion 71b of the first busbar 3 extend in a direction along the upper edge 1a of the glass plate 1, away from the upper edge 1a, than the second upper edge 6e of the first heating region 2a and the first upper portion 71a of the first busbar 3. As shown in Figure 4, when the antenna 30 is placed in the space near the upper portion 71 of the first upper busbar 3a, which is located in the upper central part of the glass plate 1, it can transmit and receive radio waves at a wide angle horizontally from near the center of the vehicle width outwards. When the projection surface 13 (see Figure 3) overlaps with the recess 81 in the upper central part of the glass plate 1, the antenna 30 can transmit and receive radio waves at a wide angle horizontally and vertically from near the center of the vehicle width outwards. For example, if antenna 30 is a V2X antenna, the bias in antenna gain is small from the center of the vehicle width towards the A-pillars on both sides of the vehicle body, making it easier to obtain balanced directivity. The center can be defined as a range of 0.30 to 0.70, 0.35 to 0.65, or 0.40 to 0.60, when the (horizontal) width of the glass plate is set to 1.

[0051] Next, the arrangement relationship between the antenna 30 and the unheated region 8 will be described. In Figure 3, θ is the angle (depression angle) between the plane L connecting the lower end 35 of the conductor 37 and the upper end 80 of the first upper portion 71a of the upper portion 71 of the first upper busbar 3a, and the horizontal plane 31. When the angle θ is 5° or more, the radio waves radiated from or received by the antenna 30 are less likely to be blocked by the upper portion 71 and the heated region 2, so that the antenna gain in a predetermined frequency band F can be secured. In terms of securing the antenna gain, the angle θ is preferably 6° or more, more preferably 7° or more, and even more preferably 8° or more. The upper limit of the angle θ is not particularly limited as long as the area of ​​the heated region 2 does not become too small, but for example, 20° or less is preferred.

[0052] Let D be the vertical length of the gap 15, and λ be the wavelength of the radio waves transmitted and received by the antenna 30 in air. In this case, if the length D satisfies "(1 / 4) × λ ≤ D", the radio waves radiated from or received by the antenna 30 will not be easily blocked by the heating region 2, and thus the antenna gain in a predetermined frequency band F can be secured. In terms of securing this antenna gain, the length D is preferably (1 / 4) × λ or greater, and more preferably ((1 / 4) × λ) / sinθ or greater.

[0053] When the frequency of the radio waves transmitted and received by antenna 30 is 5.9 GHz, if the length D is 13 mm or more, the radio waves radiated from or received by antenna 30 will be less likely to be blocked by the heated region 2, thereby ensuring antenna gain in the predetermined frequency band F.

[0054] Figure 5 is a diagram showing a plan view of a window glass in a vehicle window device in the second embodiment, illustrating one possible configuration. In the second embodiment, explanations of the same operations and effects as in the first embodiment will be omitted or simplified by referring to the explanation above. The vehicle window device 301 shown in Figure 5 differs from the vehicle window device 300 in the first embodiment in that the projection surface 13, formed by projecting the conductor 37 onto the glass plate 1 from the horizontal direction, overlaps with the heating region 2. Furthermore, if the projection surface 13 of the conductor 37 overlaps with the upper portion 71 of the first bus bar 3, it may interfere with radio waves arriving from above the vehicle or radiating upwards from the vehicle. Therefore, it is preferable to position the projection surface 13 so as not to overlap with the first bus bar 3. In particular, as shown in Figure 6, it is preferable that a gap 17 exists between the conductor 37 and the upper portion 71 of the first bus bar 3 in a plan view from inside the vehicle. Due to the presence of the gap 17, the radio waves radiated from or received by the antenna 30 are less likely to be blocked by the upper portion 71 of the first busbar 3, thereby ensuring antenna gain in a predetermined frequency band F.

[0055] In Figure 5, the antenna 30 transmits and receives vertically polarized waves. In a configuration where the conductive member 26 provided in the heating region 2 is formed from a plurality of linear conductors extending in the vertical direction of the glass plate 1 and arranged in the X-axis direction, vertical polarization parallel to the longitudinal direction of these linear conductors is easily blocked by the conductive member 26. However, because the antenna 30 is positioned in the space near the glass plate 1, antenna gain in a predetermined frequency band F is ensured. Therefore, even if the antenna 30 is spatially positioned so that the projection surface 13 overlaps with the heating region 2, a decrease in antenna gain in the predetermined frequency band F can be suppressed.

[0056] Figure 7 is a front view illustrating a plurality of linear conductors 27 contained in a conductive member 26 on a projection surface 13 formed by projecting the conductor 37 of the antenna 30 onto a glass plate 1 from a horizontal direction. Let W be the horizontal spacing between the plurality of linear conductors 27, and λ be the wavelength of the radio waves transmitted and received by the antenna 30 in air. In this case, if the spacing W satisfies "W ≥ 0.15 × λ", the radio waves radiated from or received by the antenna 30 will not be easily blocked by the plurality of linear conductors 27, thus ensuring antenna gain in a predetermined frequency band F. In terms of ensuring this antenna gain, a spacing W of 0.20λ or more is preferable, and 0.30λ or more is more preferable.

[0057] When the frequency of the radio waves transmitted and received by antenna 30 is 5.9 GHz, if the spacing W is 8 mm or more, the radio waves radiated from or received by antenna 30 will not be easily obstructed by the multiple linear conductors 27, thereby ensuring antenna gain in a predetermined frequency band F.

[0058] In Figures 5 and 6, in a plan view of the glass plate 1, if the vertical gap length G between the projection surface 13 and the upper portion 71 of the first busbar 3 is 0.25λ (=λ / 4) or more, the radio waves radiated from or received by the antenna 30 will not be easily blocked by the upper portion 71, thus ensuring antenna gain in a predetermined frequency band F. In terms of ensuring this antenna gain, a gap length G of 0.35λ or more is preferable, and 0.50λ or more is more preferable.

[0059] In each of the embodiments described above, the antenna 30 has a radiating surface 34 (see Figures 2 and 3) that emits radio waves. The vehicle window glass device 300 in each embodiment may have a dielectric 33 (see Figure 3) with a relative permittivity greater than 1 between the glass plate 1 and the radiating surface 34. The dielectric 33 allows adjustment of the frequency characteristics of the antenna 30. The dielectric 33 may be a spacer or a matching film. The dielectric 33 may also be a resin-containing material.

[0060] The radiating surface 34 may be positioned approximately parallel to the vertical direction, as shown in Figure 3, or approximately parallel to the glass plate 1, as shown in Figure 8. Even when the radiating surface 34 of the antenna 30 is positioned at an angle closer to the surface of the glass plate 1 than to the vertical direction, as shown in Figure 8, the antenna 30 is positioned via a dielectric 33 between the radiating surface 34 and the glass plate 1. In this case, the spatial area of ​​the antenna 30 installed on the inside of the vehicle can be reduced, thus increasing the interior space of the vehicle. In the example shown in Figure 8, as in Figure 3, a dielectric 33 with a relative permittivity greater than 1 may exist between the glass plate 1 and the radiating surface 34. Also, in Figure 8, the distance between the glass plate 1 and the radiating surface 34 is not particularly limited, but it should be 30 mm or less, preferably 20 mm or less, more preferably 10 mm or less, even more preferably 5 mm or less, and especially preferably 3 mm or less. The lower limit of this distance is not particularly limited, but it should be greater than 0 mm.

[0061] The angle between the main surface of the glass plate 1 and the horizontal plane is not particularly limited, but for example, the glass plate 1 is positioned at an angle of 20° or more and 30° or less with respect to the horizontal plane.

[0062] Figure 9 shows an example of simulation results of the transmission characteristics of the antenna 30 depending on the difference in the horizontal spacing W of multiple linear conductors 27 contained in the conductive member 26 within the heating region 2. In this case, the gap length G was ensured to be (1 / 4) × λ (≈ 12.7 mm) or more. Figure 9 shows the data when the radio waves transmitted and received by the antenna 30 are vertically polarized, with the projection surface 13 overlapping the heating region 2. When the spacing W is increased, the radio wave transmission is improved in the frequency band below approximately 6 GHz. In particular, when the spacing W (pitch) is 2 mm or more and 4 mm or less, the radio wave transmission in the 5.9 GHz band is improved while ensuring the heating performance of the heating region 2.

[0063] Although embodiments have been described above, the technology of this disclosure is not limited to the embodiments described above. Various modifications and improvements are possible, such as combinations or substitutions with some or all of other embodiments.

[0064] For example, vehicle windows are not limited to windshields; they may also be windows installed in other parts of the vehicle body. For instance, vehicle windows may include rear windows installed in the rear window frame, side windows installed in the side window frames, and roof windows installed in the ceiling window frame. Furthermore, the entire contents of the specification, claims, drawings, and abstract of Japanese Patent Application No. 2021-126708, filed on August 2, 2021, are incorporated herein by reference as the disclosure of the specification of this invention. [Explanation of symbols]

[0065] 1 glass plate 1a Upper edge 1b Lower edge 1c left edge 1d right edge 2 heating area 2a 1st heating area 2b 2nd heating area 3. First bus bar 3a First upper bus bar 3b Second upper bus bar 4. Second bus bar 4a First lower bus bar 4b Second lower bus bar 5 Antenna Area 6a,6b,6c,6d Vertical side 6e, 6f upper edge 6g bottom edge 7 Crank section 8 Non-heating area 9 gaps 11, 12, 21, 22 Main surfaces 13 Projection surface 14 Bottom edge 15,17 gap 16 Top 26 Conductive members 27. Stranded Conductor 30 Antennas 31,32 horizontal plane 33 Dielectrics 34 Radiating surface 35 Bottom end 36 Dielectric substrate 37 Conductor 38 Radiating elements 39 Ground Plane 51,52,55,56 electrode 53, 54 Grand Harness 57, 58 Power harness 66 Window frame 66a Upper frame 66b Bottom frame 66c Left frame 66d Right frame 70,72 lower part 71,79 Upper part 71a 1st upper part 71b 2nd upper part 71c 3rd upper part 73,76 Vertical section 74,77 Horizontal part 75,78 Connection busbars 80 top end 81 recess 82 areas 91 1st bending part 92 2nd bending part 100 window glass 300,301 Vehicle window glass device 400 power supply 401 Positive terminal 402 Negative terminal

Claims

1. Glass panels for vehicles, A first busbar is provided on the glass plate and includes an upper portion that extends in a direction along the upper edge of the glass plate, A second busbar is provided on the glass plate and includes a lower portion that extends in a direction along the lower edge of the glass plate, It comprises an antenna located in the space near the aforementioned upper portion, which transmits and receives radio waves of a predetermined frequency, The glass plate has a heated region extending between the upper portion and the lower portion, and a non-heated region extending above the upper portion. The heating region is a region where a conductive member is placed between the first busbar and the second busbar, causing a DC voltage to be applied by a power supply, thereby allowing a DC current to flow in the vertical direction. The heating region is then heated by the heat generated by the conductive member. The antenna has a conductor that is separated from the glass plate and facing the glass plate, When viewed horizontally from inside the vehicle, a gap exists between the conductor and the upper portion. The angle between the plane connecting the lower end of the conductor and the upper end of the upper portion and the horizontal plane is between 5° and 20°. Vehicle window glass device.

2. The non-heated region has a recessed area that is lowered when viewed horizontally from inside the vehicle. The vehicle window glass device according to claim 1, wherein the projection surface obtained by projecting the conductor onto the glass plate from a horizontal direction overlaps with the recess.

3. The vertical length D of the gap is such that, when λ is the wavelength of the radio waves transmitted and received by the antenna in air, (1 / 4) × λ ≤ D A vehicle window glass device according to claim 1 or 2 that satisfies the condition.

4. The vehicle window glass device according to claim 3, wherein the length D is 13 mm or more.

5. The aforementioned antenna has a radiating surface that emits radio waves, A vehicle window glass device according to any one of claims 1 to 4, wherein a dielectric with a relative permittivity greater than 1 is provided between the glass plate and the radiating surface.

6. The vehicle window glass device according to claim 5, wherein the dielectric comprises a resin.

7. The aforementioned antenna has a radiating surface that emits radio waves, The vehicle window glass device according to any one of claims 1 to 6, wherein the radiating surface is arranged substantially parallel to the glass plate.

8. The aforementioned antenna has a radiating surface that emits radio waves, The vehicle window glass device according to any one of claims 1 to 7, wherein the radiating surface is arranged substantially parallel to the vertical direction.

9. The vehicle window glass device according to any one of claims 1 to 8, wherein the antenna is a patch antenna.

10. The vehicle window glass device according to any one of claims 1 to 9, wherein the antenna is arranged in the space near the upper portion of the horizontal central part of the glass plate.

11. The vehicle window glass device according to any one of claims 1 to 10, wherein the glass plate is arranged at an angle of 20° or more and 30° or less with respect to the horizontal plane.

12. The vehicle window glass device according to any one of claims 1 to 11, wherein the antenna transmits and receives radio waves including at least one of the 5.8 GHz band and the 5.9 GHz band.

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