On-vehicle window glass

Abstract

To provide a high-quality on-vehicle window glass causing less change in gain between when the window glass is a unit and when the window glass is attached to a vehicle body.SOLUTION: An on-vehicle window glass attached to a vehicle body includes: a communication antenna disposed on an upper side located above or a lower side located below a test region A determined by safety standards of road transport vehicles in the on-vehicle window glass; and a pair of radio wave propagation inhibition member on left and right sides of the communication antenna.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] This disclosure relates to vehicle glazing. [Background technology]

[0002] When a vehicle-mounted window glass has an antenna that transmits and receives radio waves, the antenna characteristics measured on its own may differ from those measured when the window glass is attached to the vehicle body.

[0003] For example, Patent Document 1 (International Publication No. 2015 / 19904) describes an antenna device that can reduce interference between two antenna elements when they are arranged close to the same conductor such as a roof. Also, Patent Document 2 (Japanese Patent Laid-Open Publication No. 2022-110357) describes a vehicle antenna device that can reduce interference between antennas arranged close to each other and can save space. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] International Publication No. 2015 / 19904 [Patent Document 2] Japanese Patent Publication No. 2022-110357 Summary of the Invention [Problem to be solved by the invention]

[0005] Because 5G mobile communication systems use high-frequency radio waves, there are bands in which the VSWR characteristics change significantly between when the glass is used alone and when it is installed in the vehicle, particularly for vehicle window glass equipped with an antenna that transmits and receives 5G mobile communication system signals. Antennas must have a VSWR of less than 3, as a VSWR of 3 or higher could cause transmitter failure. Because the antenna is designed with the vehicle body in mind, the VSWR when installed in the vehicle is less than 3. However, since the glass is inspected alone during manufacturing, the VSWR exceeds 3, reducing the reliability of the inspection results. Therefore, there is a need for high-quality vehicle window glass that minimizes the change in VSWR between when it is used alone and when it is installed in the vehicle, and meets the standards both when used alone and when installed in the vehicle. [Means for solving the problem]

[0006] In other words, what is disclosed in this specification is a vehicle window glass that is attached to a vehicle body and is characterized by having a communication antenna that is positioned on the upper edge side above or the lower edge side below test area A specified in the safety standards for road transport vehicles of the vehicle window glass, and a pair of radio wave propagation suppression members on the left and right sides of the communication antenna.

[0007] The present disclosure also provides a vehicle window glass, wherein the radio wave propagation suppressing member is a conductor.

[0008] The present disclosure also provides a vehicle window glass, wherein the radio wave propagation suppression member is disposed along a side edge of the vehicle window glass.

[0009] The present disclosure also provides a vehicle window glass, wherein the radio wave propagation suppression member is disposed along a lower edge or an upper edge of the vehicle window glass.

[0010] The present disclosure also provides a vehicle window glass, characterized in that the radio wave propagation suppression member is formed by a conductive paint applied to the surface of the vehicle window glass, and forms a light-shielding area along the left and right side edges of the vehicle window glass.

[0011] The present disclosure also provides a vehicle window glass, wherein the radio wave propagation suppressing member is a broadcast receiving antenna.

[0012] The present disclosure also provides a vehicle window glass, wherein the radio wave propagation suppression member is an antenna for receiving terrestrial digital television broadcasts.

[0013] The present disclosure also provides a vehicle window glass, wherein the radio wave propagation suppression member is formed by firing a silver paste applied to the surface of the vehicle window glass, is formed from fullerene in which carbon atoms are bonded together in a spherical shape, is formed from a transparent metal film, or is formed from a transparent conductive oxide film.

[0014] The present disclosure also relates to a vehicle window glass, characterized in that the radio wave propagation suppression member is formed from a conductive adhesive applied to the surface of the vehicle window glass, or is a bracket for attaching an electronic device to the vehicle window glass and includes a conductive member. [Effects of the Invention]

[0015] According to a representative embodiment of the present invention, a high-quality vehicle window glass can be provided that exhibits little change in gain between when it is used alone and when it is attached to a vehicle body, and satisfies standards both when it is used alone and when it is attached to a vehicle body. [Brief explanation of the drawings]

[0016] [Figure 1] 1 is a plan view of a vehicle window glass according to an embodiment of the present invention, viewed from inside the vehicle. [Figure 2] FIG. 4 is an enlarged view of another vehicle window glass according to an embodiment of the present invention, as viewed from inside the vehicle. [Figure 3] FIG. 10 is a plan view of another vehicle window glass according to an embodiment of the present invention, as viewed from the inside of the vehicle. [Figure 4] 1 is a diagram for explaining the operation principle of an embodiment of the present invention; [Figure 5] 10A and 10B are diagrams for explaining the effects of the embodiment of the present invention. DETAILED DESCRIPTION OF THE INVENTION

[0017] FIG. 1 is a plan view of a vehicle window glass 10 according to an embodiment of the present invention, as viewed from inside the vehicle.

[0018] A vehicle window glass 10 shown in FIG. 1 has a communication antenna 11 and radio wave propagation suppressing members 12 provided on the left and right sides of the communication antenna 11.

[0019] An opaque layer 15 is provided around the periphery of the vehicle window glass 10. For example, the opaque layer 15 is formed by firing a colored ceramic paste. The vehicle window glass 10 is attached to the vehicle body 5 at the opaque layer 15 with an adhesive.

[0020] The communication antenna 11 is disposed on the upper side of the vehicle window glass 10 and is connected to a wireless communication device via a power supply line (not shown) extending from above. For example, the communication antenna 11 transmits and receives signals of a 5G mobile communication system. The upper side of the vehicle window glass 10 is located above a test area A defined by the safety standards for road vehicles.

[0021] Test area A is defined as follows in Japanese Industrial Standard JIS R 3212:2015:

[0022] Test area A is the area on the outer surface of the windshield that is bounded by the following four planes extending from point V in the -X direction: 1.1) A plane that passes through point V1, is parallel to the Y axis, and is inclined 3° in the +Z direction with respect to the X axis. 1.2) A plane that passes through point V2, is parallel to the Y axis, and is inclined 1° in the -Z direction with respect to the X axis. 1.3) A vertical plane that passes through points V1 and V2 and is inclined 13° in the +Y direction of the X axis. 1.4) A vertical plane that passes through points V1 and V2 and is inclined 20° in the -Y direction of the X axis. 2) When the driving position is near the center of the vehicle (the Y coordinate of point R is within Y0 ± 60 mm), test area A may be the area of ​​the outer surface of the windshield surrounded by the following four planes extending from point V in the -X direction. 2.1) A plane that passes through point V1, is parallel to the Y axis, and is inclined 3° in the +Z direction with respect to the X axis. 2.2) A plane that passes through point V2, is parallel to the Y axis, and is inclined 1° in the -Z direction with respect to the X axis. 2.3) A vertical plane that passes through points V1 and V2 and is inclined 15° toward the +Y direction of the X axis. 2.4) A vertical plane that passes through points V1 and V2 and is inclined 15° in the -Y direction of the X axis.

[0023] The communication antenna 11 has a first element 31 to which a core wire of the power feeder line is connected, and a ground element 32 to which a ground conductor of the power feeder line is connected.

[0024] The first element 31 forms a triangle with the ground element 32 as the apex, and is wider on the lower side that is farther from the vehicle body 5. A blank area without conductors may be provided inside the first element 31, and multiple auxiliary elements extending in the vertical and / or horizontal directions may be provided in this blank area.

[0025] Radio wave propagation suppressing members 12 are disposed on the left and right sides of the communication antenna 11. As shown in FIG. 1, the radio wave propagation suppressing members 12 are preferably disposed along the left and right sides of the vehicle window glass 10. Alternatively, as shown in FIG. 2, the radio wave propagation suppressing member 12 may be disposed along the top or bottom side of the vehicle window glass 10. The radio wave propagation suppressing member 12 is preferably formed from a sheet-like conductor (surface resistivity 1 to 300 Ω / sq) or magnetic material (magnetic permeability 10 to 2000 H / m). As an example of the radio wave propagation suppressing member 12, a sheet-like electric heater element can be used.

[0026] The communication antenna 11 is formed by printing a conductive silver paste in a predetermined width on the glass surface of the vehicle window glass 10 on the interior side of the vehicle or on the opaque layer 15, drying it, and then baking it in a heating furnace. Alternatively, the communication antenna 11 may be formed by forming an antenna conductor using a conductive pattern formed on a light-transmitting resin film, and then attaching the resin film on which the antenna conductor is formed to the glass. By arranging at least a portion of the communication antenna 11 on the opaque layer 15, the communication antenna 11 becomes difficult to see from outside the vehicle, improving its appearance.

[0027] The radio wave propagation suppression member 12 may be an electrically floating conductor that is not connected to anything, as shown in FIG. 1, a conductor connected to ground potential (not shown), or an antenna that transmits or receives other radio waves, as shown in FIG. 2.

[0028] The radio wave propagation suppressing member 12 is formed by printing a conductive silver paste with a predetermined width on the interior glass surface of the vehicle window glass 10, on the interior side of the exterior glass in the case of a laminated windshield, or on the opaque layer 15, and then baking it in a heating oven after drying. Alternatively, the radio wave propagation suppressing member 12 may be formed by forming a conductive pattern on a light-transmitting resin film, and then attaching the resin film with the radio wave propagation suppressing member 12 to the glass. Placing at least a portion of the radio wave propagation suppressing member 12 on the opaque layer 15 makes the radio wave propagation suppressing member 12 less visible from outside the vehicle, improving the appearance. Alternatively, the radio wave propagation suppressing member 12 may be formed by applying a conductive paint to the surface of the vehicle window glass 10. Forming the radio wave propagation suppressing member 12 using a colored, transparent conductive paint can form a light-blocking region that reduces external light along the left and right sides of the vehicle window glass 10. Alternatively, the radio wave propagation suppression member 12 may be made of fullerene, which is a spherically bonded group of carbon atoms. Alternatively, the radio wave propagation suppression member 12 may be made of a transparent metal film on the surface of the vehicle window glass 10, a transparent conductive oxide film on the surface of the vehicle window glass 10, or a conductive adhesive applied to the surface of the vehicle window glass 10.

[0029] A bracket for mounting an electronic device (for example, an information acquisition device that acquires information about the outside world) may be provided in a position surrounding the mounting position on the vehicle window glass 10. The bracket may function as the radio wave propagation suppression member 12. For this purpose, the bracket is made of a conductive material (for example, a conductor), and may be formed, for example, by printing a conductive silver paste with a predetermined width, drying it, and then baking it in a heating furnace.

[0030] FIG. 2 is an enlarged view of a vehicle window glass 10 according to another embodiment of the present invention, seen from inside the vehicle, showing a communication antenna 11 and its surroundings.

[0031] The vehicle window glass 10 shown in FIG. 2 has a communication antenna 11 and second antennas 20 provided on the left and right of the communication antenna 11, and the second antennas 20 function as the radio wave propagation suppressing member 12.

[0032] The communication antenna 11 is arranged on the upper side of the vehicle window glass 10 and is connected to the wireless communication device via a power supply line 13 extending from above. The communication antenna 11 may also be arranged on the lower side of the vehicle window glass 10.

[0033] An opaque layer 15 is provided around the periphery of the vehicle window glass 10. The vehicle window glass 10 is attached to the vehicle body 5 at the opaque layer 15 with an adhesive.

[0034] Second antennas 20 are arranged on the left and right sides of the communication antenna 11. The second antennas 20 may be arranged along the upper edge of the vehicle window glass 10, as shown in Fig. 2. Alternatively, the second antennas 20 may be arranged along the lower edge of the vehicle window glass 10.

[0035] The second antenna 20 is, for example, an antenna for receiving terrestrial digital television broadcasts that receives radio waves in the range of 470 to 710 MHz, and includes a core-side feeding section 21, a ground-side feeding section 22, a plurality of core-side elements 23 and 24 connected to the core-side feeding section 21, and a plurality of ground-side elements 25 connected to the ground-side feeding section 22. The core-side feeding section 21 and the ground-side feeding section 22 are arranged side by side (i.e., at approximately the same position in the vertical direction). The second antenna 20 may be, for example, an antenna for receiving radio broadcasts.

[0036] Of the core-side elements 23, 24, the first core-side element 23 extends outward from the core-side feed portion 21, away from the communication antenna 11. The second core-side element 24 extends downward from the core-side feed portion 21, with its tip bent outward. The tip of the second core-side element 24 may extend outward as shown in FIG. 2 , inward, or downward without bending. Bending the tip of the second core-side element 24 can improve the gain for radio waves arriving from an oblique direction. The core-side element 23 is preferably positioned at a distance of 20 mm or more from the vehicle body 5 to avoid capacitive coupling. The total length of the first core side element 23 and the second core side element 24 (for example, 140 mm in FIG. 2) may be between αλL / 4 and αλH / 2, where λH is the upper wavelength (wavelength at 710 MHz) of the receiving frequency (digital terrestrial television broadcasting band 470 to 710 MHz), λL is the lower wavelength (wavelength at 470 MHz), and α is the wavelength shortening rate of the glass.

[0037] The ground-side element 25 extends downward from the ground-side feeding portion 22 and then bends outward to extend away from the communication antenna 11. The tip of the ground-side element 25 may extend outward as shown in Figure 2, may extend inward, or may extend downward without bending.

[0038] The communication antenna 11 and the second antenna 20 are formed by printing a conductive silver paste in a predetermined width on the glass surface of the vehicle interior side of the vehicle window glass 10 or on the opaque layer 15, drying it, and then baking it in a heating furnace. Alternatively, the communication antenna 11 and the second antenna 20 may be formed by forming an antenna conductor using a conductive pattern formed on a light-transmitting resin film, and then attaching the resin film on which the antenna conductor is formed to the vehicle window glass 10. By arranging at least a portion of the communication antenna 11 or the second antenna 20 on the opaque layer 15, the second antenna 20 becomes difficult to see from outside the vehicle, improving its appearance.

[0039] FIG. 3 is a plan view of another vehicle window glass 10 according to an embodiment of the present invention, as viewed from the inside of the vehicle.

[0040] The vehicle window glass 10 shown in FIG. 3 has a communication antenna 11 and radio wave propagation suppressing members 12 provided on the left and right sides of the communication antenna 11.

[0041] An opaque layer 15 is provided around the periphery of the vehicle window glass 10. For example, the opaque layer 15 is formed by firing a colored ceramic paste. The vehicle window glass 10 is attached to the vehicle body 5 at the opaque layer 15 with an adhesive.

[0042] The communication antenna 11 is disposed on the lower side of the vehicle window glass 10 and is connected to a wireless communication device via a power supply line (not shown) extending from below. For example, the communication antenna 11 transmits and receives signals of a 5G mobile communication system. The lower side of the vehicle window glass 10 is located below a test area A defined by the safety standards for road vehicles.

[0043] The communication antenna 11 has a first element 31 to which a core wire of the power feeder line is connected, and a ground element 32 to which a ground conductor of the power feeder line is connected.

[0044] The first element 31 forms a triangle with the ground element 32 as the apex, and is wider on the upper side that is farther from the vehicle body 5. A blank area without conductors may be provided inside the first element 31, and multiple auxiliary elements extending in the vertical and / or horizontal directions may be provided in this blank area.

[0045] Radio wave propagation suppressing members 12 are disposed on the left and right sides of the communication antenna 11. As shown in FIG. 3, the radio wave propagation suppressing members 12 are preferably disposed along the left and right sides of the vehicle window glass 10. The radio wave propagation suppressing members 12 are preferably made of a sheet-like conductor (surface resistivity 1 to 300 Ω / sq) or magnetic material (magnetic permeability 10 to 2000 H / m). One example of the radio wave propagation suppressing member 12 is a sheet-like electric heater element.

[0046] The communication antenna 11 is formed by printing a conductive silver paste in a predetermined width on the glass surface of the vehicle window glass 10 on the interior side of the vehicle or on the opaque layer 15, drying it, and then baking it in a heating furnace. Alternatively, the communication antenna 11 may be formed by forming an antenna conductor using a conductive pattern formed on a light-transmitting resin film, and then attaching the resin film on which the antenna conductor is formed to the glass. By arranging at least a portion of the communication antenna 11 on the opaque layer 15, the communication antenna 11 becomes difficult to see from outside the vehicle, improving its appearance.

[0047] The radio wave propagation suppression member 12 may be an electrically floating conductor that is not connected to anything, as shown in FIG. 3, a conductor connected to ground potential (not shown), or an antenna that transmits or receives other radio waves, as shown in FIG. 2.

[0048] The radio wave propagation suppressing member 12 is formed by printing a conductive silver paste with a predetermined width on the interior glass surface of the vehicle window glass 10, on the interior side of the exterior glass in the case of a laminated windshield, or on the opaque layer 15, and then baking it in a heating oven after drying. Alternatively, the radio wave propagation suppressing member 12 may be formed by forming a conductive pattern on a light-transmitting resin film, and then attaching the resin film with the radio wave propagation suppressing member 12 to the glass. Placing at least a portion of the radio wave propagation suppressing member 12 on the opaque layer 15 makes the radio wave propagation suppressing member 12 less visible from outside the vehicle, improving the appearance. Alternatively, the radio wave propagation suppressing member 12 may be formed by applying a conductive paint to the surface of the vehicle window glass 10. Forming the radio wave propagation suppressing member 12 using a colored, transparent conductive paint can form a light-blocking region that reduces external light along the left and right sides of the vehicle window glass 10. Alternatively, the radio wave propagation suppression member 12 may be made of fullerene, which is a spherically bonded group of carbon atoms. Alternatively, the radio wave propagation suppression member 12 may be made of a transparent metal film on the surface of the vehicle window glass 10, a transparent conductive oxide film on the surface of the vehicle window glass 10, or a conductive adhesive applied to the surface of the vehicle window glass 10.

[0049] A bracket for mounting an electronic device (for example, an information acquisition device that acquires information about the outside world) may be provided in a position surrounding the mounting position on the vehicle window glass 10. The bracket may function as the radio wave propagation suppression member 12. For this purpose, the bracket is made of a conductive material (for example, a conductor), and may be formed, for example, by printing a conductive silver paste with a predetermined width, drying it, and then baking it in a heating furnace.

[0050] FIG. 4 is a diagram for explaining the operating principle of the embodiment of the present invention.

[0051] As shown in FIG. 4 , radio waves emitted from the communication antenna 11 are reflected by the top and bottom edges of the vehicle window glass 10 and reach the side edges, resulting in a large gain on the sides. As a result, the characteristics of the communication antenna 11 change depending on the conductors on the sides. For example, the characteristics of the communication antenna 11 of this embodiment measured alone differ from those when attached to the vehicle body 5, and there is a risk that the characteristics of the communication antenna 11 will not meet the specified standards when the vehicle window glass 10 is attached to the vehicle body 5. For this reason, radio wave propagation suppression members 12 provided on the left and right sides of the communication antenna 11 suppress radio waves radiated from the communication antenna 11, reflected by the top and bottom edges of the vehicle window glass 10, and reaching the side edges, thereby suppressing the change in the characteristics of the communication antenna 11 measured alone and those when attached to the vehicle body 5.

[0052] FIG. 5 is a diagram for explaining the effect of the embodiment of the present invention.

[0053] 5 is a graph showing the VSWR characteristics (solid line) of the communication antenna 11 alone and the VSWR characteristics (dashed line) when the antenna is attached to the vehicle body 5, with the vertical axis representing VSWR and the horizontal axis representing frequency (GHz). FIG. 5(A) shows the characteristics when the second antenna 20 is not provided, and FIG. 5(B) shows the characteristics when the second antenna 20 is provided. As can be seen from comparing FIGS. 5(A) and 5(B), when the second antenna 20 is provided, the difference between the VSWR characteristics (solid line) of the communication antenna 11 alone and the VSWR characteristics (dashed line) when the antenna is attached to the vehicle body 5 becomes smaller. For example, in the 700 MHz to 750 MHz (Band 28) frequency range, in the case of FIG. 5(A) where the second antenna is not provided, the VSWR of the communication antenna 11 alone is 3.5 and the VSWR of the communication antenna 11 when attached to the vehicle body is 1.7 (the difference in VSWR characteristics is 1.8), whereas in the case of FIG. 5(B) where the second antenna is provided, the VSWR of the communication antenna 11 alone is 1.8 and the VSWR of the communication antenna 11 when attached to the vehicle body (on-board) is 2.7 (the difference in VSWR characteristics is 0.9).

[0054] As described above, the vehicle window glass 10 according to the embodiment of the present invention has radio wave propagation suppression members 12 made of a conductive material disposed on the glass surfaces on the left and right sides of the communication antenna 11, which transmits and receives signals for a 5G mobile communication system. This suppresses the peak gain of the communication antenna 11. This reduces the difference between the characteristics of the communication antenna 11 on the vehicle window glass 10 alone and the characteristics of the communication antenna 11 when the vehicle window glass 10 is attached to the vehicle body 5. This makes it possible to manage the radio wave transmission characteristics of the communication antenna 11 when the vehicle window glass 10 is attached to the vehicle body 5 using the radio wave transmission characteristics of the communication antenna 11 on the vehicle window glass 10 alone, making it easier to manage the production and inspection of the vehicle window glass 10.

[0055] Although the present invention has been described in detail above with reference to the accompanying drawings, the present invention is not limited to such specific configurations, and includes various modifications and equivalent configurations within the spirit of the appended claims. [Explanation of symbols]

[0056] 5. Body 10. Automotive window glass 11 Communication antenna 12 Radio wave propagation suppression materials 13 Power line 15 Opaque layer 20 Second Antenna 21 Core side power supply part 22 Ground side power supply 23 First core element 24 Second core element 25 Ground element 31 First Element 32 Grand Element

Claims

1. A vehicle window glass that is attached to a vehicle body, a communication antenna disposed on an upper side or a lower side of the vehicle window glass above a test area A defined by the road transport vehicle safety standards; A vehicle window glass comprising a pair of radio wave propagation suppressing members on the left and right sides of the communication antenna.

2. The vehicle window glass according to claim 1, The vehicle window glass is characterized in that the radio wave propagation suppressing member is a conductor.

3. The vehicle window glass according to claim 1, The vehicle window glass, wherein the radio wave propagation suppressing member is disposed along a side edge of the vehicle window glass.

4. The vehicle window glass according to claim 1, The vehicle window glass, wherein the radio wave propagation suppressing member is disposed along a bottom edge or a top edge of the vehicle window glass.

5. The vehicle window glass according to claim 3, The vehicle window glass is characterized in that the radio wave propagation suppression member is formed by a conductive paint applied to the surface of the vehicle window glass, and forms light-blocking areas along the left and right sides of the vehicle window glass.

6. The vehicle window glass according to claim 1, The vehicle window glass is characterized in that the radio wave propagation suppressing member is a broadcast receiving antenna.

7. The vehicle window glass according to claim 6, The vehicle window glass is characterized in that the radio wave propagation suppressing member is an antenna for receiving terrestrial digital television broadcasts.

8. The vehicle window glass according to claim 1, The radio wave propagation suppressing member is The glass is formed by firing a silver paste applied to the surface of the vehicle window glass. It is formed by fullerenes, which are spherically bonded carbon atoms. formed of a transparent metal film, or A vehicle window glass formed from a transparent conductive oxide film.

9. The vehicle window glass according to claim 1, The radio wave propagation suppressing member is A vehicle window glass characterized in that it is formed of a conductive adhesive applied to the surface of the vehicle window glass, or is a bracket for attaching an electronic device to the vehicle window glass, and includes a conductive member.

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