JP6639089B2 - Window glass for vehicles - Google Patents

Description

  The present invention relates to a window glass for a vehicle.

  On the surface of a window glass for a vehicle attached to an automobile or the like, a conductive wire portion including a hot wire portion for removing dew condensation or melting icing, and a power supply portion for supplying power to the hot wire portion is provided. May be provided. The conductive strips are formed by printing a conductive paste such as silver on the surface of the window glass and baking it.

  As an example of a window glass having such a conductive wire portion, for example, in Patent Document 1, a heating wire provided on each of a lower end side and a side end side of a glass plate, and disposed at a lower end of the glass plate, There has been proposed a windshield including a conductor pattern having a power supply electrode for supplying power to a heating wire. In this windshield, a heating wire is arranged in a region where a wiper operates to push out water droplets, ice, snow, frost, and the like. Then, by causing the heating filament to generate heat, ice or the like attached to this region can be melted.

JP 2012-14006 A

  In the above-described window glass, when the hot wire portion is heated, a region heated by the hot wire portion and a region not heated occur, so that a large temperature difference occurs around the region where the hot wire portion is arranged in the glass plate. Occurs. As in Patent Document 1, when a hot wire is arranged near an end such as a lower end or a side end of a glass plate, when the hot wire is brought closer to the end of the glass plate, a region where this large temperature difference occurs also has a glass. It approaches the edge of the board. Then, a large temperature difference generated around the hot wire portion affects, and the thermal stress acting on the end of the glass plate increases. Since large thermal stresses cause cracks at the edges of the glass sheet, separate the hot wire from the edges of the glass sheet, that is, make sure that the region where a large temperature difference occurs is not too close to the edges of the glass sheet, The thermal stress acting on the edge of the glass plate is reduced.

  However, the inventor of the present invention has found that the following problems may occur by separating the hot wire from the end of the glass plate in this manner. That is, if the heating wire is too far from the end of the glass plate, the length of the power supply portion extending from the end of the glass plate to supply power to the heating wire increases. When heating the hot wire portion, the current flowing in the hot wire portion also flows in the power supply portion, so that the power supply portion also generates heat. As the length of the power supply unit increases, the area heated by the power supply unit increases. The inventor of the present invention has found that, due to this effect, thermal stress acting near the end of the glass plate provided with the power supply unit increases.

  The present invention, in one aspect, has been made in view of such circumstances, and its purpose is to reduce the increase in thermal stress near the edge of a glass sheet even when the hot wire is separated from the edge of the glass sheet. It is to provide the technology to control.

  The present invention employs the following configuration in order to solve the above-described problems.

  That is, the window glass according to one aspect of the present invention is a window glass for a vehicle, which is formed of a glass plate and a conductive material, and includes a conductive linear portion disposed on any surface of the glass plate. The conductive wire portion is disposed apart from the end of the glass plate, a heating wire portion having a predetermined pattern so as to heat a predetermined region of the glass plate, and from near the end of the glass plate A power supply unit that extends and is connected to the hot wire unit and supplies power to the hot wire unit. The power supply section is partially thinned.

  According to this configuration, the power supply unit is partially thinned. That is, the line width of the power supply unit is partially reduced. As the line width decreases, the resistance value at that portion increases, so that the amount of heat generated at the portion having the reduced line width generally increases. On the other hand, in the entire power supply unit, the area for heating the glass plate becomes narrow, in other words, the area for radiating the heat of the power supply unit becomes large. Therefore, even if the amount of heat generated in the power supply unit is partially increased, it is possible to radiate heat more than the amount of increase in the amount of heat generated. Therefore, according to this configuration, even if the length of the power supply unit is increased by separating the hot wire from the end of the glass plate, the amount of heat generated in the entire power supply unit can be suppressed. An increase in thermal stress near the end can be suppressed.

  In addition, the predetermined pattern of the heating wire portion can be appropriately determined according to the embodiment. Further, the conductive material may be, for example, silver, gold, platinum, or the like, and may be appropriately selected according to the embodiment as long as the above-described use of the conductive wire portion can be achieved. Further, the vicinity of the end of the glass plate may be in a state of being in contact with the end of the glass plate, or may be in a state of being separated from the end of the glass plate to such an extent that wiring from a power supply of the vehicle can be connected. There may be. The region near the edge of the glass plate includes a region where the thermal stress generated at the edge of the glass plate due to heat generated by the power supply unit may increase.

  Further, as another form of the window glass according to the one side surface, the power supply unit, a base disposed near the end of the glass plate, a line width narrower than the base, a thin line portion extending from the base, May be provided. According to this configuration, the power supply section has a narrower line width on the distal end side, and can suppress the amount of heat generated around that portion. As a result, an increase in thermal stress near the end of the glass plate can be suppressed.

  Further, as another form of the window glass according to the one side surface, a plurality of the thin wire portions may be provided, the plurality of the thin wire portions may be separated from each other, and the heating wire portion may be any one of the plurality of the thin wire portions. It may be configured to be supplied with power by being connected to a crab. According to this configuration, connection with various forms of the heating wire portion is facilitated, and the degree of freedom in designing the conductive wire portion can be increased.

  Further, as another form of the window glass according to the one side surface, the heating wire portion may be separately connected to each of the plurality of thin wire portions. Among the conductive wire portions, the heat wire portion is a region having a high calorific value. According to this configuration, the hot wire portion is divided into a plurality of thin wire portions and connected. Here, since the plurality of thin wire portions are separated from each other, the connecting portion between the heating wire portion and each thin wire portion can be separated. That is, since a region having a high calorific value can be separated, the amount of heat generated in the vicinity of the power supply unit can be suppressed according to the configuration, thereby increasing the thermal stress near the edge of the glass plate. Can be suppressed.

  Further, as another form of the window glass according to the one side surface, a distance between the plurality of thin line portions may be longer than a line width of each of the plurality of thin line portions. According to this configuration, the width of the region between adjacent thin line portions is configured to be longer than the line width of each thin line portion. Therefore, the size of the region between the adjacent thin wire portions can be sufficiently ensured, and the heat generated in each thin wire portion can be sufficiently radiated by this region. Therefore, according to the configuration, it is possible to suppress a rise in the temperature of the entire power supply unit, and thereby to sufficiently suppress a rise in thermal stress near the end of the glass plate.

  Further, as another form of the window glass according to the one side surface, a base of the power supply unit may be disposed so as to be in contact with an end of the glass plate. The base of the power supply unit is a portion having a large line width, and is connected to wiring from a power supply of the vehicle. According to this configuration, since the base is disposed so as to be in contact with the end of the glass plate, connection of wiring from the power source of the vehicle is facilitated.

  Further, as another form of the window glass according to the one aspect, the conductive material may include silver. Silver is highly conductive, relatively easily available, and inexpensive. Therefore, according to the configuration, a high-quality conductive wire portion can be formed at low cost.

  Further, as another form of the window glass according to the one aspect, the window glass may be used as a windshield of an automobile. Glass sheets used in automotive windshields are generally not reinforced. If the glass sheet is not reinforced, the glass sheet relatively easily cracks due to thermal stress generated at the edge of the glass sheet. On the other hand, according to the configuration, it is possible to suppress an increase in thermal stress near the end of the glass plate. Therefore, even if the glass sheet is not strengthened, the possibility of cracking can be reduced. In addition, the strengthening means, for example, after heating a glass plate to about 700 ° C., rapidly cooling the glass plate to have a compression layer on the surface of the glass plate, thereby increasing the strength of the glass plate to about 3 to 5 times. It is to raise.

  ADVANTAGE OF THE INVENTION According to this invention, even if it separates a hot-wire part from the edge part of a glass plate, the rise of the thermal stress near the edge part of a glass plate can be suppressed.

FIG. 1 is a plan view schematically illustrating a window glass according to the embodiment. FIG. 2 is a partially enlarged view schematically illustrating the power supply unit according to the embodiment. FIG. 3 schematically illustrates a manufacturing process of the window glass according to the embodiment. FIG. 4 is a partially enlarged view schematically illustrating a power supply unit according to another embodiment. FIG. 5 is a partially enlarged view schematically illustrating a power supply unit according to another embodiment. FIG. 6 is a plan view schematically illustrating a hot wire unit according to another embodiment. FIG. 7 shows a temperature distribution in the vicinity of the power supply portion when the hot wire portion of the window glass according to the reference example is heated. FIG. 8 shows a thermal stress distribution in the vicinity of the power supply part when the hot wire part of the window glass according to the reference example is heated. FIG. 9 shows a temperature distribution in the vicinity of the power supply portion when the hot wire portion of the window glass according to the comparative example is heated. FIG. 10 shows a thermal stress distribution in the vicinity of the power supply part when the hot wire part of the window glass according to the comparative example is heated. FIG. 11 illustrates a temperature distribution in the vicinity of the power supply unit when the hot wire of the window glass according to the example is heated. FIG. 12 shows a thermal stress distribution in the vicinity of the power supply part when the hot wire part of the window glass according to the example is heated.

  Hereinafter, an embodiment according to one aspect of the present invention (hereinafter, also referred to as “the present embodiment”) will be described with reference to the drawings. However, the present embodiment described below is merely an example of the present invention in every respect. It goes without saying that various improvements and modifications can be made without departing from the scope of the invention. That is, in implementing the present invention, a specific configuration according to the embodiment may be appropriately adopted.

§1 Configuration Example First, a window glass 1 according to the present embodiment will be described with reference to FIG. FIG. 1 is a plan view schematically illustrating a window glass 1 according to the present embodiment. For convenience of explanation, the up-down direction in FIG. 1 is referred to as “up / down” and the left-right direction in FIG. 1 is referred to as “left / right”. FIG. 1 illustrates the window glass 1 viewed from the inside of the vehicle. That is, the back side of the paper of FIG. 1 is the outside of the vehicle, and the near side of the paper of FIG. 1 is the inside of the vehicle.

  The window glass 1 according to the present embodiment is a window glass for a vehicle attached to an automobile, specifically, a windshield of the automobile. As illustrated in FIG. 1, the window glass 1 includes a substantially rectangular glass plate 10, and is attached to an automobile at a slight angle from the vertical. The glass plate 10 has an upper end 11 extending in the left-right direction, a lower end 12 slightly facing the upper end 11, a right end 13 connecting right ends of the upper end 11 and the lower end 12, and an upper end 11. And a left end portion 14 connecting the left ends of the portion 11 and the lower end portion 12 to each other.

  On the inner surface of the glass plate 10, a shielding layer 3 that shields the field of view from outside the vehicle is provided along the periphery of the glass plate 10. On the shielding layer 3, a conductive strip 2 having a predetermined pattern is formed from the lower end 12 to the left end 14. Hereinafter, each of these components will be described.

<Glass plate>
First, the glass plate 10 will be described. The glass plate 10 according to the present embodiment is used as a window glass of an automobile, and is configured in a shape corresponding to a window frame of the automobile to be mounted. In the present embodiment, the glass plate 10 has a substantially rectangular shape in a plan view, and also has a concave inner side surface and a convex outer side surface from a peripheral portion to a central portion in a side view. It is formed in a curved shape.

  Such a glass plate 10 can have various configurations depending on the embodiment. The glass plate 10 may be a known glass plate for an automobile. For example, heat-absorbing glass, general clear glass or green glass, or UV green glass may be used for the glass plate 10. However, such a glass plate 10 needs to realize visible light transmittance in accordance with safety standards of the country where the automobile is used. For example, it can be adjusted so that solar absorptivity, visible light transmittance, and the like satisfy safety standards. Hereinafter, an example of the composition of the clear glass and an example of the composition of the heat ray absorbing glass will be described.

(Clear glass)
SiO ₂ : 70 to 73% by mass
Al ₂ O _3: 0.6~2.4 wt%
CaO: 7 to 12% by mass
MgO: 1.0 to 4.5 mass%
R ₂ O: 13 to 15% by mass (R is an alkali metal)
Fe total iron oxide in terms of _{2 O 3 (T-Fe 2} O 3): 0.08~0.14 wt%

(Heat absorbing glass)
The composition of the heat-absorbing glass, for example, based on the composition of the clear glass, the proportion of the total iron oxide in terms of _{Fe 2 O 3 (T-Fe} 2 O 3) and 0.4 to 1.3 wt%, CeO ₂ is 0 to 2% by mass, the ratio of TiO ₂ is 0 to 0.5% by mass, and the skeleton components (mainly SiO ₂ and Al ₂ O ₃ ) of the glass are T-Fe ₂ O ₃ and CeO. ₂ and TiO ₂ can be reduced in composition.

  Note that the type of the glass plate 10 is not limited to clear glass, heat ray absorbing glass, and the like, and can be appropriately selected according to the embodiment. For example, the glass plate 10 may be a resin window such as an acrylic resin or a polycarbonate resin.

  Further, the thickness of the glass plate 10 according to the present embodiment is not particularly limited. However, from the viewpoint of weight reduction, the thickness of the glass plate 10 may be set in the range of 2.2 to 5.1 mm, or may be set in the range of 2.4 to 3.8 mm. It may be set in the range of 7 to 3.2 mm. Further, the thickness of the glass plate 10 may be set to be equal to or less than 3.1 mm.

<Shielding layer>
Next, the shielding layer 3 will be described. As illustrated in FIG. 1, in the present embodiment, the shielding layer 3 is formed on a peripheral portion of the inner surface of the glass plate 10. The shielding layer 3 is provided in order to make the mounting portion of the glass plate 10 and the like invisible from outside the vehicle. Therefore, the region where the shielding layer 3 is provided can be appropriately selected and set according to the embodiment.

  The material of the shielding layer 3 may be appropriately selected according to the embodiment as long as it can shield the field of view from the outside of the vehicle, and a dark ceramic such as black, brown, gray, or dark blue may be used. . For example, a black ceramic is laminated on the inner surface of the glass plate 10 by screen printing or the like, and the ceramic laminated together with the glass plate 10 is heated. Thereby, the shielding layer 3 having a single-layer structure can be formed on the periphery of the window glass 1. Various materials can be used for the ceramic used for the shielding layer 3. For example, a ceramic having the following composition can be used for the shielding layer 3.

* 1, main components: copper oxide, chromium oxide, iron oxide, and manganese oxide * 2, main components: bismuth borosilicate, zinc borosilicate

  Note that the thickness of the shielding layer 3 can be appropriately set. For example, the thickness of the shielding layer 3 can be set in a range of 10 μm to 20 μm. The shielding layer 3 shields the field of view from the outside of the vehicle and cuts ultraviolet rays, thereby preventing deterioration of an adhesive for attaching the glass plate 10 to the vehicle body.

<Conductive filament>
Next, the conductive line portion 2 will be described with reference to FIG. FIG. 2 is a partially enlarged view illustrating the power supply portions 23 to 25 of the conductive wire portion 2. As illustrated in FIG. 1 and FIG. 2, the conductive linear portion 2 according to the present embodiment is disposed on the inner surface of the glass plate 10 via the shielding layer 3. The conductive wire portion 2 supplies power to two heat wire portions (21, 22) having a predetermined pattern so as to heat a predetermined region of the glass plate 10, and to each heat wire portion (21, 22). And three power supply units 23 to 25.

  The heating wire portion 21 is disposed apart from the lower end portion 12, and is provided along the lower end portion 12 from a position slightly closer to the right to the vicinity of the right end portion 13 of the glass plate 10. Further, the heating wire portion 22 is arranged apart from the lower end portion 12, extends along the lower end portion 12 from the slightly rightward center of the glass plate 10 to near the left end portion 14, and thereafter, from the vicinity of the lower end portion 12 to the upper end portion. 11 extends along the left end portion 14. The areas where the heating wires (21, 22) are provided correspond to the standby position and the reversing position of the wiper (not shown). Such a pattern of each heating wire portion (21, 22) can be appropriately changed according to the embodiment.

  On the other hand, each of the power supply units 23 to 25 extends upward from the lower end 12 of the glass plate 10 to supply power to each of the hot wire portions (21, 22), and is connected to each of the hot wire portions (21, 22). The power supply units 23 and 25 are positive electrodes, and the power supply unit 24 is a negative electrode. Therefore, the power supply unit 23 is connected to the hot wire unit 21, and the power supply unit 25 is connected to the hot wire unit 22. In addition, the power supply unit 24 is connected to both the hot wire units (21, 22).

  A harness 4 having three terminals is attached to each of the power supply units 23 to 25 by soldering or the like, and a wiring (not shown) from a power supply of the vehicle is connected to each of the power supply units 23 to 25 via this harness. You. Therefore, the driver of the automobile can supply electricity to the conductive wire portion 2 by operating the operation panel (not shown).

  When electricity is supplied to the conductive wire portion 2, an electric current is generated in each of the heating wire portions (21, 22) via each of the power supply portions 23 to 25. Then, the hot wire portions (21, 22) are heated by the energy of the flowing electricity, and the glass plate 10 is heated in the region where the hot wire portions (21, 22) are formed. As a result, the frozen wiper can be warmed, and ice or the like attached to this region can be melted.

  However, each heating wire part (21, 22) is provided apart from the lower end part 12 of the glass plate 10 where the power supply parts 23 to 25 are arranged. Therefore, when each of the heating wire portions (21, 22) is too far from the lower end portion 12, the length of each of the power supply portions 23 to 25 becomes long. Then, as described above, the thermal stress in the vicinity of the end of each of the power supply portions 23 to 25, that is, in the vicinity of the region where the power supply portions 23 to 25 are provided in the lower end portion 12 of the glass plate 10, increases. Cracks may occur. On the other hand, in the present embodiment, the heat generation amount of each of the power supply units 23 to 25 is suppressed by subdividing each of the power supply units 23 to 25. This suppresses an increase in thermal stress in the vicinity of this region, and reduces the possibility of cracking. Hereinafter, each configuration will be described in detail.

(Power supply unit)
First, the power supply units 23 to 25 will be described. Each of the power supply portions 23 to 25 is arranged near the lower end portion 12 of the glass plate 10, extends inward in the surface direction, and is connected to each of the hot wire portions (21, 22). Each of the power supply units 23 to 25 is partially thinned. Specifically, the power supply unit 23 has a wide rectangular base 230 disposed near the lower end 12 of the glass plate 10 and a rectangular base 230 extending upward from the base 230 and having a smaller line width than the base 230. And a thin line portion 231.

  The power supply unit 24 includes a base 240 similar to the base 230 and four thin lines 241 to 244 each extending upward from an end of the base 240 and having a smaller line width than the base 240. Each of the thin line portions 241 to 244 is formed in a rectangular shape, and is disposed apart from each other in the left-right direction.

  However, the thin line portion 244 is configured to have a larger line width than the other thin line portions 241 to 243, is bent rightward near the base 240, and then extends upward. The thin line portion 243 is connected to a bent portion of the thin line portion 244. In this way, the thin line portion may branch off in the middle of the extension.

  The power supply unit 25 includes a base 250 similar to the base 230 and the base 240, and three thin lines 251 to 253 each extending upward from an end of the base 250 and having a smaller line width than the base 250. ing. Each of the thin line portions 251 to 253 is formed in a rectangular shape, and is disposed apart from each other in the left-right direction. Of such thin line portions 251 to 253, the thin line portion 251 is configured to have a larger line width than the other thin line portions (252, 253).

  Each terminal of the harness 4 is attached to each base (230, 240, 250) of each of the power supply units 23 to 25. Therefore, each base (230, 240, 250) is configured to have a certain line width so as to be able to withstand a large current from the power source of the automobile.

  For example, from the viewpoint of connectivity with the harness 4, the width of each base (230, 240, 250) of each of the power supply units 23 to 25 is preferably set in a range of 10 mm to 20 mm. However, the width of each base (230, 240, 250) does not have to be limited to such a range and can be appropriately selected according to the embodiment.

  Further, it is preferable that each base (230, 240, 250) is arranged so as to be in contact with the end (the lower end 12 in the present embodiment) of the glass plate 10 so that the harness 4 can be easily bonded. However, as long as the harness 4 can be bonded, the bases (230, 240, 250) may be slightly separated from the end of the glass plate 10. That is, the vicinity of the end of the glass plate 10 may be in a state of being in contact with the end of the glass plate 10, and the glass plate 10 may be connected to the wiring (harness 4) from the power source of the vehicle to such an extent that it can be connected. The state may be away from the end. The region near the end of the glass plate 10 includes a region where the heat stress generated at the end of the glass plate 10 due to the heat generated by the power supply units 23 to 25 can increase.

  On the other hand, the thin line portions (231, 241-244, 251-253) do not have the same requirements as the bases (230, 240, 250), so that the line width can be reduced. However, since the resistance value increases when the line width is reduced, the heat value generally increases. On the other hand, a region that is not heated by each of the power supply units 23 to 25 is widened, and thus a region for radiating generated heat is widened. In the present embodiment, each line portion (231, 241 to 244, 251 to 253) of each of the power supply units 23 to 25 is reduced in line width to take advantage of the fact that such a heat radiation area is expanded. The amount of heat generated by the power supply units 23 to 25 is suppressed.

  For example, from the viewpoint of suppressing an amount of heat generated in each of the power supply units 23 to 25 while supplying an appropriate amount of current to each of the hot wire units (21, 22), the thin wire units (231, 241-244, 251-253) The width is preferably set in the range of 1 mm to 10 mm. Further, the width of each thin line portion (231, 241-244, 251-253) is more preferably set to 5 mm or less. However, the width of each thin line portion (231, 241-244, 251-253) is not limited to such a range, and can be appropriately selected according to the embodiment.

  Note that the distance between the thin line portions (231, 241-244, 251-253), that is, the distance between adjacent thin line portions may be configured to be longer than the line width of each thin line portion. According to this configuration, the width of the region between adjacent thin line portions is configured to be longer than the line width of each thin line portion (231, 241-244, 251-253). Therefore, the size of the region between the adjacent fine wire portions can be sufficiently ensured, and the heat generated in each of the fine wire portions (231, 241-244, 251-253) can be sufficiently radiated by this region. . Therefore, it is possible to suppress a rise in the temperature of the entire power supply units 23 to 25, thereby sufficiently suppressing an increase in thermal stress in the lower end portion 12 of the glass plate 10 in the vicinity of the region where the power supply units 23 to 25 are provided. Can be.

(Hot wire part)
Next, each heating wire part (21, 22) will be described. In the present embodiment, the heating wire portion 21 is constituted by two elongated filaments (211 and 212). Each line (211 and 212) extends along the lower end 12 from the vicinity of the upper end of the thin wire portion 231 of the power supply unit 23 toward the right end 13, and turns back once near the right end 13 to move toward the power supply unit 23. Come back. Each line (211, 212) is folded back near the upper side of the power supply portion 23 and again extends along the lower end 12 toward the right end 13. Then, each of the filaments (211, 212) is folded again near the right end portion 13, returns to the power supply portion 24, and is connected to the upper end of the thin wire portion 244 of the power supply portion 24.

  The heating wire portion 22 is composed of five elongated wires 221 to 225. Of these, the three filaments 221 to 223 extend along the lower end 12 from the vicinity of the upper end of each of the thin wire portions 251 to 253 of the power supply unit 25 toward the left end 14, and are folded back near the left end 14. To return to the power supply unit 24, and is connected to the vicinity of the upper end of each of the thin wire portions 241 to 243 of the power supply unit 24. On the other hand, the two filaments (224, 225) located outside are connected to the thin line portion 251 of the power supply unit 25 below the position where the filament 221 is connected, and toward the left end portion 14. It extends along the lower end 12. Further, each of the lines (224, 225) is bent near the left end portion 14 and extends toward the upper end portion 11 along the left end portion 14. Then, each of the filaments (224, 225) is folded back near the upper end portion 11, returned to the vicinity of the lower end portion 12, and further bent near the lower end portion 12 to return to the power supply portion 24. 244 near the upper end.

  In addition, in order to obtain an appropriate calorific value in each heating wire part (21, 22), the line width of each line (211, 212, 221-225) of each heating wire part (21, 22) is 0.5 mm or more. Preferably, it is set within a range of 10 mm. Further, it is more preferable that the line width of each line (211, 212, 221-225) of each heating wire portion (21, 22) is set to 3 mm or less. However, the line width of each line (211, 212, 221 to 225) of each heating wire portion (21, 22) does not have to be limited to these ranges, and can be appropriately selected according to the embodiment.

(Other)
In the present embodiment, the conductive wire portion 2 is configured by each of the heat wire portions (21, 22) and each of the power supply portions 23 to 25. Such a conductive linear portion 2 is formed by laminating a conductive material having conductivity on the inner surface of the glass plate 10, more specifically, on the shielding layer 3. The material of the conductive wire portion 2 only needs to have conductivity, and can be appropriately selected in the embodiment. Examples of the material of the conductive wire portion 2 include silver, gold, platinum and the like. For example, the conductive linear portion 2 can be formed by printing a conductive silver paste containing silver powder, glass frit, and the like on the shielding layer 3 and baking it. Note that silver has high conductivity, is relatively easily available, and is inexpensive. Therefore, in order to form the high-quality conductive wire portion 2 at low cost, the conductive material preferably contains silver.

Next, a method for manufacturing the window glass 1 according to the present embodiment will be described with reference to FIG. FIG. 3 schematically illustrates a shaping step of the glass plate 10 according to the present embodiment. In addition, the manufacturing process of the window glass 1 described below is only an example, and each manufacturing process may be changed as much as possible. In the manufacturing process described below, steps can be omitted, replaced, and added as appropriate according to the embodiment.

  As illustrated in FIG. 3, in this production line, a heating furnace 901 and a forming apparatus 902 are arranged in this order from upstream to downstream. A roller conveyor 903 is arranged from the heating furnace 901 to the forming apparatus 902 and a downstream side thereof, and the glass sheet 10 to be processed is conveyed by the roller conveyor 903.

  The glass plate 10 is formed in a flat plate shape before being carried into the heating furnace 901. Then, a black ceramic is laminated on the periphery of the inner surface of the glass plate 10 by screen printing or the like, and calcined at about 200 ° C. for about 20 minutes. Thereby, the shielding layer 3 is formed on the peripheral portion of the flat glass plate 10. After the formation of the shielding layer 3, a conductive silver paste containing silver powder, glass frit, or the like is printed on the shielding layer 3 so as to form a pattern of the conductive linear portion 2. Thereafter, the glass sheet 10 is carried into the heating furnace 901.

  Although various configurations are possible for the heating furnace 901, for example, an electric heating furnace can be used. The heating furnace 901 has a furnace body of a rectangular tubular shape whose upstream and downstream ends are open, and a roller conveyor 903 is disposed inside the heating furnace 901 from upstream to downstream. A heater (not shown) is disposed on each of the upper surface, the lower surface, and a pair of side surfaces of the inner wall surface of the furnace main body, and a temperature at which the glass sheet 10 passing through the heating furnace 901 can be formed, for example, a softening point of glass. Heat to near. For example, the heating furnace 901 heats the glass plate 10 at about 650 ° C. As a result, the glass plate 10 can be formed, and the silver paste is fired to form the conductive linear portions 2.

  The forming apparatus 902 is configured to press a glass plate with an upper mold 921 and a lower mold 922 to form the glass plate into a predetermined shape. The upper die 921 has a curved shape that is convex downward so as to cover the entire upper surface of the glass plate 10 and is configured to be vertically movable. The lower mold 922 is formed in a frame shape corresponding to the periphery of the glass plate 10, and the upper surface thereof has a curved shape so as to correspond to the upper mold 921. With this configuration, the glass plate 10 is press-formed between the upper die 921 and the lower die 922 to be formed into a final curved surface shape. A roller conveyor 903 is arranged in the frame of the lower mold 922, and the roller conveyor 903 can be moved up and down so as to pass through the frame of the lower mold 922. Although not shown, a slow cooling device (not shown) is disposed downstream of the forming device 902, and the formed glass plate 10 is cooled. Thereby, the window glass 1 is manufactured.

[Characteristic]
In the window glass 1 according to the present embodiment, each of the power supply units 23 to 25 is thinned. Specifically, each of the power supply units 23 to 25 has a narrow line width on the distal end side by each of the thin line portions (231, 241, to 244, 251, to 253). When the line width is reduced, the resistance value at that portion increases. Therefore, generally, the calorific value increases in each of the thin line portions (231, 241-244, 251-253). On the other hand, gaps are provided between the thin wire portions (231, 241-244, 251-253), that is, the area heated by the power supply sections 23-25 becomes narrower, and the area for radiating the generated heat becomes wider. Become. For this reason, according to the present embodiment, even if the heating value is partially increased in each of the thin line portions (231, 241-244, 251-253), heat is radiated in each gap more than the increased heating value. It is possible to Therefore, according to this configuration, each of the heating wire portions (21, 22) is separated from the lower end portion 12 of the glass plate 10, and even if the length of each of the power supply portions 23 to 25 is increased, the entirety of the power supply portions 23 to 25 is increased. The amount of generated heat can be suppressed. As a result, it is possible to suppress an increase in thermal stress in the lower end portion 12 of the glass plate 10 in the vicinity of the region where the power supply portions 23 to 25 are provided.

  Further, in the present embodiment, a plurality of fine line portions (231, 241-244, 251-253) are provided. Therefore, various connection of each filament (211, 212, 221-225) of each heating wire part (21, 22) and each thin wire part (231, 241-244, 251-253) becomes possible, and a conductive wire The degree of freedom in designing the ridges 2 can be increased.

  Further, in the present embodiment, each line (211, 212, 221 to 225) of each heating wire section (21, 22) is divided and connected to a plurality of thin wire sections (231, 241 to 244, 251 to 253). . In the region of the conductive wire portion 2, each of the heating wire portions (21, 22) is a region having a high calorific value, and in particular, each of the heating wire portions (211, 212, 221-225) and each of the thin wire portions (231, 241-241). 244, 251-253), the calorific value increases. On the other hand, according to the said structure, since each thin line part (231, 241-244, 251-253) is spaced apart, each line (211,212, 221-225) and each thin line part (231, 241). 241 to 244, 251 to 253) can be separated from each other. As a result, a region having a high calorific value can be separated, and according to the present embodiment, the amount of heat generated around each of the power supply units 23 to 25 can be suppressed. An increase in thermal stress near the (lower end portion 12) can be suppressed.

§3 Modifications While the embodiments of the present invention have been described in detail, the above description is merely illustrative of the present invention in every respect. It goes without saying that various improvements and modifications can be made without departing from the scope of the invention. In the following, the same components as those in the above-described embodiment are denoted by the same reference numerals, and description thereof will not be repeated.

(Window glass)
For example, in the above embodiment, the window glass 1 is a windshield for an automobile. However, the window glass to which the present invention can be applied is not limited to the windshield of an automobile, and can be appropriately selected according to the embodiment.

  In addition, glass sheets used for windshields for automobiles are not generally reinforced. If the glass sheet is not reinforced, the glass sheet relatively easily cracks due to thermal stress generated at the edge of the glass sheet.

  On the other hand, according to the above-described embodiment, it is possible to suppress an increase in thermal stress in a region where the power supply units 23 to 25 are provided at the end (the lower end 12) of the glass plate 10. Therefore, even if the glass sheet 10 is not strengthened, the possibility of cracking can be reduced.

  In addition, the strengthening means, for example, after heating a glass plate to about 700 ° C., rapidly cooling the glass plate to have a compression layer on the surface of the glass plate, thereby increasing the strength of the glass plate to about 3 to 5 times. It is to raise.

(Glass plate)
Further, for example, regarding the above specific configuration of the glass plate 10, the omission, change, replacement, and addition of the components may be appropriately performed according to the embodiment. For example, the glass plate 10 has a shape curved forward, but may have a flat shape. Further, the glass plate 10 is formed in a substantially rectangular shape. However, the shape of the glass plate 10 is not limited to the above embodiment, but can be appropriately selected according to the embodiment.

  Further, the glass plate 10 is constituted by one glass plate. However, the glass plate 10 may be made of a laminated glass in which an outer glass plate and an inner glass plate are bonded to each other via an intermediate film. In this case, the conductive line portion 2 may be laminated on the inner surface of the outer glass plate. Accordingly, a cutout may be provided in a part of the inner glass plate corresponding to the power supply units 23 to 25 so that the harness 4 can be attached to the power supply units 23 to 25. .

  When the conductive line portions 2 are laminated on the inner surface of the outer glass plate in this way, when each of the power supply units 23 to 25 is separated from the vicinity of the end of the outer glass plate inward in the surface direction, the inner glass plate is removed. The notch provided in the area corresponding to the power supply portions 23 to 25 of the plate becomes larger by the distance.

  In order to prevent the notch provided in the inner glass plate from becoming large, a method of reducing the radius of curvature of the notch may be considered. However, it is technically necessary to provide such a notch having a small radius of curvature in the inner glass plate. Difficult. For this reason, when each of the power supply units 23 to 25 is separated from the vicinity of the end of the outer glass plate inward in the surface direction, it is difficult to prevent the notch provided in the inner glass plate from becoming large.

  When the notch becomes large, the strength of the inner glass plate is reduced, and the whole glass plate is easily broken. In addition, a sealing material is applied around the notch to maintain airtightness and the like. However, if the notch becomes large, the amount of the sealing material used increases, and the manufacturing cost increases. Would.

  Therefore, for these reasons, when the glass plate 10 is used as a windshield and the glass plate 10 is made of laminated glass, each power supply is separated from near the end of the outer glass plate inward in the surface direction. Providing the parts 23 to 25 is avoided. That is, each of the power supply units 23 to 25 is provided near the end of the outer glass plate, particularly, so as to be in contact with or near the end of the outer glass plate.

(Shielding layer)
Further, for example, in the above-described embodiment, the shielding layer 3 is provided along the periphery of the window glass 1. However, the region where the shielding layer 3 is provided can be appropriately set according to the embodiment. However, if the shielding layer 3 overlaps the driver's field of view, the driver's view will be obstructed by the shielding layer 3 during driving. Therefore, it is preferable to set the area of the shielding layer 3 so as not to overlap with the driver's field of view. Note that the shielding layer 3 may be omitted. In this case, the conductive linear portions 2 are directly laminated on the surface of the glass plate 10.

  Further, for example, in the above embodiment, the shielding layer 3 has a single-layer structure. However, the shielding layer 3 can have a multilayer structure. For example, the first ceramic layer is formed by laminating a ceramic on the inner surface of the glass plate 10. Next, a silver layer is formed by stacking silver on the first ceramic layer. Further, a second ceramic layer is formed by laminating a ceramic on the silver layer. Thereby, the shielding layer 3 having a three-layer structure can be formed. The shielding layer 3 having the three-layer structure can shield electromagnetic waves by the silver layer. In addition, materials having the composition shown in Table 2 below can be used for this silver layer.

* 1, Main components: bismuth borosilicate, zinc borosilicate

  Further, for example, in the above embodiment, the shielding layer 3 is laminated on the inner surface of the glass plate 10. However, the surface on which the shielding layer 3 is laminated is not limited to the inner surface, and may be the outer surface. When the glass plate 10 is composed of a plurality of glass plates, one or more surfaces on which the shielding layer 3 is laminated may be appropriately selected from the surfaces of the plurality of glass plates.

  In addition, by laminating the ceramic on the inner surface of the glass plate 10, the adhesiveness when the window glass 1 is attached to the automobile can be improved. In addition, since the shielding layer 3 serves as a cushion between the glass plate 10 and the mounting portion of the automobile, the window glass 1 can be prevented from being easily broken at the mounting portion.

(Conductive wire section)
In addition, regarding the specific configuration of the conductive wire portion 2, the omission, change, replacement, and addition of the components may be appropriately performed according to the embodiment. For example, the arrangement of the heating wire portions, the number of filaments forming the heating wire portion, the arrangement of each filament, the shape of each filament, the number of fine wire portions, the number of power supply portions, and the like may be appropriately selected according to the embodiment. .

  As an example, each of the hot wire portions (21, 22) may be formed so as to have a predetermined pattern so as to heat a predetermined area of the glass plate 10, and the arrangement of the hot wire portions (21, 22) may be provided. The region to be performed can be appropriately selected according to the embodiment. In addition, the conductive line portion 2 may be formed on a surface of the glass plate 10 on the outside of the vehicle.

  Further, as exemplified in FIG. 4, the number of thin line portions extending from each base (230, 240, 250) may be appropriately selected according to the embodiment. FIG. 4 exemplifies a conductive linear portion 5 according to another embodiment. The conductive wire portion 5 illustrated in FIG. 4 includes two heat wire portions (51, 52) and three power supply portions 53 to 55.

  The power supply unit 53 serving as a positive electrode has a base 530 and one thin line portion 531 having a smaller line width than the base 530. Similarly, the power supply unit 55 serving as a positive electrode includes a base 550 and one thin line 551 having a smaller line width than the base 550. On the other hand, the power supply unit 54 as a negative electrode has a base 540 and two thin line portions (541 and 542) each having a smaller line width than the base 540.

  On the other hand, the three filaments 511 to 513 of the heating wire portion 51 extend from the vicinity of the upper end of the thin wire portion 531 of the power supply portion 53, turn back, and return to the vicinity of the upper end of the thin wire portion 541 on the right side of the power supply portion 54. ing. Out of the four wires 521 to 524 of the heating wire portion 52, two wires (521, 522) arranged outside extend from around the middle abdomen of the thin wire portion 551 of the power supply portion 55, and are folded back. It has returned to the vicinity of the upper end of the thin line portion 542 on the left side of the power supply unit 54. On the other hand, the two filaments (523, 524) arranged on the inner side are repeatedly folded in the same manner as the above-mentioned respective heating wire portions (211 and 212), and finally, the thin wire portion 542 on the left side of the power supply portion 54. Is coming back near the top.

  The number of such filaments in the heating wire portion and the correspondence between the thin wire portion and the heating wire portion (filament) can be appropriately selected according to the embodiment. Further, the correspondence between the positive electrode and the negative electrode of the power supply unit may be opposite.

  Further, as illustrated in FIG. 5, the number of the power supply units is not limited to three, and the number of the hot wire units is not limited to two. It can be appropriately selected according to the form. FIG. 5 exemplifies a conductive linear portion 6 according to another embodiment. The conductive wire portion 6 illustrated in FIG. 5 includes one heat wire portion 61 and two power supply portions (62, 63).

  The power supply unit 62 serving as a positive electrode includes a base 620 and two thin line portions (621 and 622) having a line width smaller than that of the base 620. Note that the thin line portion 622 arranged on the inner side has a larger line width than the thin line portion 621 arranged on the outer side.

  The power supply unit 63 as a negative electrode includes a base 630 and two thin lines (631, 632) having a line width smaller than that of the base 630. Similarly to the power supply unit 62, in the power supply unit 63, the line width of the thin line portion 631 arranged on the inside is larger than the line width of the line portion 632 arranged on the outside. The line width of such a thin line portion can be appropriately changed.

  On the other hand, the heating wire part 61 has five filaments 611-615. Two of the lines (611, 612) are connected to a thin line portion 621 and a thin line portion 632 having a smaller line width. On the other hand, the three lines 613 to 615 are connected to the thin line portions 622 and 631 having a larger line width. As described above, the line width of the thin wire portion may be changed according to the number of the filaments of the hot wire portion.

  Further, the line width of the thin wire portion of the power supply portion may be the same as the line width of the hot wire portion. That is, the thin wire portion of the power supply portion may have a shape integral with the filament of the hot wire portion.

  Further, in the above-described embodiment, the hot wire portion 21 and the hot wire portion 22 extend from the lower end portion 12 of the glass plate 10. Further, the heating wire portion 21 and the heating wire portion 22 are formed of the same material. However, the arrangement and material of the heating wire may be appropriately selected according to the embodiment. For example, the heating wire section may be configured as illustrated in FIG.

  FIG. 6 illustrates a window glass 1A including a heating wire 71 according to another embodiment. In the window glass 1A, the glass plate 10 is formed in a trapezoidal shape. The window glass 1A includes a heating wire portion 71 and two power supply portions (72, 73) for supplying electricity to the heating wire portion 71, and constitutes a so-called wire-heated windshield.

  Specifically, the heating wire portion 71 includes a bus bar portion 711 extending along the upper end portion 11 and the left end portion 14, a bus bar portion 712 extending along the lower end portion 12, and a plurality of connecting portions between the bus bar portions (711, 712). The line 713 of FIG. Here, each bus bar portion (711, 712) may be formed by a copper film tape. On the other hand, each filament 713 may be formed of a conductive metal wire or the like. For example, a tungsten wire can be used for each wire 713. As described above, the material of each portion of the heating wire portion 71 can be appropriately selected according to the embodiment.

  Each of the power supply units (72, 73) has a base (721, 731) disposed so as to be in contact with the lower end 12, and a thin line (722, 732) extending from the base (721, 731). are doing. The thin wire section 722 of the power supply section 72 is connected to the bus bar section 712 of the hot wire section 71, and the thin wire section 732 of the power supply section 73 is connected to the bus bar section 711 of the hot wire section 71. Wiring from a power source from an automobile is connected to each of the power supply units (72, 73). As a result, electricity can be supplied to the hot wire unit 71 via the power supply units (72, 73). Note that, as in this modification, the bus bar portion may be handled as one region of the hot wire portion. Further, when wiring from an automobile is connected to the bus bar portion, the bus bar portion may be treated as one region of the power supply portion.

  Further, in the above embodiment, each base (230, 240, 250) is arranged near the lower end 12 of the glass plate 10, and each thin line portion (231, 241-244, 251-253) is placed on each base (230, 240, 240). , 250) are disposed on the inner side in the plane direction of the glass plate 10. However, the positional relationship between each base portion and each thin line portion is not limited to such an example, and may be appropriately set according to the embodiment. That is, in each power supply unit, the area to be thinned may be appropriately set according to the embodiment.

(Molding device)
Further, for example, in the above-described embodiment, the forming apparatus 902 for press-molding the glass plate 10 has been described. However, the method of forming the glass plate 10 of the window glass 1 is not limited to such an example. For example, the glass plate 10 may be formed by a self-weight bending method in which the glass plate 10 is bent by its own weight. In the dead-weight bending method, the forming device has, for example, a ring-shaped (frame-shaped) forming die. The molding die is arranged on a carrier, and the flat glass plate 10 is placed on the molding die. In this state, the transfer table sequentially passes through the heating furnace and the annealing furnace. At this time, since the molding die has a ring shape, the glass plate 10 passes through the heating furnace in a state where only the peripheral portion is supported. Then, when the glass sheet 10 is heated to around the softening point temperature in the heating furnace, the inner side of the glass plate 10 is curved downward by its own weight and is formed into a curved surface.

  Hereinafter, examples of the present invention will be described. However, the present invention is not limited to this embodiment.

<1>
First, in order to verify how much the thermal stress acting near the region where the power supply unit is provided at the end of the glass plate increases when the power supply unit arranged at the end of the glass plate is lengthened, the following is performed. Such a simulation was performed. That is, as the window glass according to the reference example, a window glass having substantially the same configuration as that of the above-described embodiment except for the shape of the power supply unit was assumed. In the reference example, the three power supply units are not subdivided and have a simple rectangular shape. The glass plate in this reference example was a laminated glass in which a 0.76 mm interlayer was disposed between an outer glass plate having a thickness of 2.0 mm and an inner glass plate having a thickness of 1.8 mm. The conductive material for forming the conductive strips was silver paste. The pattern of the heating wire portion is as shown in FIG. 1. The line width of each line (211, 212, 221 to 223) is 1.0 mm to 2.0 mm, and the line width of each line (224, 225) is 3 mm. 0.0 mm to 7.0 mm. Further, the heating value of each wire is 2000 W / m ² , the total resistance of the entire circuit is 1.16 Ω to 1.56 Ω, and the sheet resistance of each heating wire is 5.0 mΩ / sqr to 7.0 mΩ / sqr. did. Further, the heating wire portion was set at a distance of 40 mm from the lower end of the glass plate in the vicinity of the power supply portion, and each power supply portion did not have a base portion and a thin wire portion, and had a rectangular shape. In addition, the length of each power supply part was 50 mm, 80 mm, and 42 mm. The width of each power supply unit was set to 20 mm in common.

  On the other hand, a window glass having the same configuration as that of the reference example, in which the heating wire portion is further separated from the lower end of the glass plate by 40 mm in the vicinity of the power supply portion and the length of each power supply portion is 88 mm, 110 mm, and 75 mm, is a comparative example. And That is, in the comparative example, the heating wire portion was 85 mm away from the lower end portion of the glass plate near the power supply portion. In the window glass according to the reference example and the comparative example, heat generation of the conductive wire portion is performed under the conditions of an ambient temperature of 20 to 25 ° C., an energizing voltage of 12 V, and an energizing time of 25 minutes or more (when the current is stable). Using the analysis software (Abaqus) capable of calculating the thermal stress in the glass plate, the temperature change and the thermal stress change occurring in the window glass according to the reference example and the comparative example were simulated. The results are shown in FIGS.

  FIG. 7 shows a temperature distribution (simulation result) near the power supply portion of the window glass in the reference example. FIG. 8 shows a thermal stress distribution (simulation result) near the power supply portion of the window glass according to the reference example. On the other hand, FIG. 9 shows a temperature distribution (simulation result) near the power supply portion of the window glass in the comparative example. FIG. 10 shows a thermal stress distribution (simulation result) near the power supply portion of the window glass according to the comparative example.

  In the reference example, the thermal stress of the region (hereinafter, also referred to as “the base of the power supply portion”) at the lower end of the glass plate, that is, the portion indicated by the arrow P1 in FIG. 8 was 5 MPa. On the other hand, in the comparative example, the thermal stress in the portion indicated by the arrow P2 in FIG. 10 was 18 MPa, and it was found that the thermal stress generated in this portion was significantly increased by lengthening the power supply portion.

  The cause was presumed as follows. That is, as can be seen from the comparison between the arrow H1 in FIG. 7 and the arrow H2 in FIG. 9, the longer the power supply unit, the wider the area where the temperature is high in the area where the power supply unit is arranged. Then, as indicated by the arrow C1 in FIG. 8 and the arrow C2 in FIG. 10, the area where the stress acts in the compression direction is widened. In the window glass according to the comparative example, a large thermal stress (tensile force) acts on the base (the portion indicated by the arrow P2) of the power supply unit in order to balance the stress in the region where the stress acts in the compression direction. It was estimated that.

  Here, from the comparison between the reference example and the comparative example, the region where the stress acts in the compression direction is also widened corresponding to the widened region where the temperature is high. Therefore, by narrowing the high-temperature region, that is, by lowering the temperature of the region where the power supply unit is provided, the region where the stress acts in the compression direction also becomes narrower, and the thermal stress acting on the base of the power supply unit also decreases. It was estimated. Then, the present inventor has come up with the present invention in which the leading end side of the power supply unit is partially thinned.

<2>
Next, in order to verify how much the thermal stress generated in the glass plate can be reduced by subdividing the power supply unit, the following simulation was performed. That is, as the window glass according to the example, a window glass having a power supply unit similar to that of the above embodiment was assumed. Each base had a width of 20 mm and a length of 20 mm. The length of the thin line portion corresponding to the thin line portion 231 was 65 mm, and the line width was 8 mm. The lengths of the thin line portions corresponding to the thin line portions 241 to 243 were 56 mm, 62 mm, and 55 mm, respectively, and the line width was 3 mm in common. The length of the thin line portion corresponding to the thin line portion 244 was 70 mm, and the line width was 8 mm. The length of the thin line portion corresponding to the thin line portion 251 was 40 mm, and the line width was 8 mm. The lengths of the thin line portions corresponding to the thin line portions (252, 253) were 46 mm and 51 mm, respectively, and the line width was 3 mm in common. Other conditions of the window glass according to the example were the same as those of the comparative example. That is, the arrangement of the heating wires in the example was the same as that of the comparative example.

  In the window glass of such an example, a change in temperature and a change in thermal stress occurring in the window glass according to the example were simulated using analysis software (Abaqus) under the same conditions as described above. The results are shown in FIGS. FIG. 11 shows a temperature distribution (simulation result) in the vicinity of the power supply portion of the window glass in the example. Numeral 11 shows a thermal stress distribution (simulation result) near the power supply portion of the window glass in the example.

  Referring to FIGS. 9 and 11, the temperature of the region where the power supply unit is provided is slightly lower in the example than in the comparative example. Accordingly, the region where the stress acts in the compression direction indicated by arrow C3 also became narrower, and the thermal stress acting on the portion indicated by arrow P3 also decreased to 14.5 MPa. Therefore, it was shown that by subdividing the power supply unit, the thermal stress acting on the base of the power supply unit can be sufficiently reduced.

1. Window glass,
10: glass plate, 11: upper end, 12: lower end, 13: right end, 14: left end,
2 ... conductive stripes,
21: heating wire portion, 211: striated line, 212: striated line,
22 ... hot wire part, 221-225 ... filament,
23 ... power supply section, 230 ... base section, 231 ... thin line section,
24 ... power supply section, 240 ... base section, 241 to 244 ... thin line section,
25 ... power supply section, 250 ... base section, 251 to 253 ... thin line section,
3 ... shielding layer,
4 ... harness,
5 ... conductive wire section,
51: hot wire portion, 511 to 513: filament,
52: hot wire portion, 521 to 524: wire,
53 ... power supply section, 530 ... base section, 531 ... thin line section,
54: power supply section, 540: base section, 541, 542: thin line section,
55 ... power supply section, 550 ... base section, 551 ... thin line section,
6 ... conductive wire section,
61: hot wire portion, 611 to 615: filament,
62: power supply section, 620: base section, 621/622: thin line section,
63: power supply unit, 630: base unit, 631, 632: thin line unit,
71: hot wire section, 711/712: bus bar section, 713: wire,
72: power supply section, 721: base section, 722: thin line section,
73 ... power supply section, 731 ... base section, 732 ... thin line section,
901: heating furnace, 902: molding device, 921: upper die, 922: lower die,
903: Roller conveyor, 931: Roller

Claims (6)

A window glass for a vehicle comprising a glass plate and a conductive material, comprising a conductive linear portion disposed on any surface of the glass plate,
The conductive wire portion,
A heating wire portion that is disposed apart from an end of the glass plate and has a predetermined pattern so as to heat a predetermined region of the glass plate,
A power supply unit extending from an end of the glass plate, connected to the hot wire unit, and supplying power to the hot wire unit;
With
The power supply unit,
A base disposed near an end of the glass plate,
A plurality of thin line portions having a line width narrower than the base portion and extending from the base portion;
Has,
The hot wire portion is supplied with power by being connected to any of the plurality of thin wire portions,
Since the plurality of fine wire portions are separated from each other, a region for radiating heat is provided.
Window glass. The heat wire portion is connected to each of the plurality of thin wire portions separately,
The window glass according to claim 1 . The distance separating the plurality of thin line portions is configured to be longer than the line width of each of the plurality of thin line portions,
The window glass according to claim 1 . A base of the power supply unit is arranged to be in contact with an end of the glass plate.
The window glass according to any one of claims 1 to 3 . The conductive material includes silver,
The window glass according to any one of claims 1 to 4 . The window glass is used as a windshield of an automobile,
The window glass according to any one of claims 1 to 5 .