Indication device

Abstract

The present invention provides a display device that can make the welded area difficult to see while increasing the bonding strength of the welded area. [Solution] A display device 100 comprising a protective panel member 1 having a light-transmitting region 1b and a light-shielding region 1c formed by a light-shielding printed layer 1e, a display unit 2 disposed on the back side of the protective panel member 1, and a case member 4 supporting the back portion 1d on the outer periphery side of the protective panel member 1, wherein the protective panel member 1 and the case member 4 are joined by laser welding, the color of the printed layer 1e is the same as or similar to the color of the case member 4, the back portion 1d on the outer periphery side of the protective panel member 1 has a non-printed area 1f where the printed layer 1e is not formed at a position corresponding to the joining region S by laser welding, and the outer surface portion of the protective panel member 1 has a flat surface, a tapered surface 1h, or a curved surface 1i in the region facing the welded portion Y by laser welding.

Description

Technical Field

[0001] The present disclosure relates to a display device.

Background Art

[0002] There is known a display device in which a light-transmissive protective panel member and a case member are joined by laser welding. For example, in the display device of Patent Document 1, a light-shielding layer and a semi-transmissive layer are printed on the back surface portion of a protective panel, and the protective panel member and the case member are welded with laser light transmitted through the semi-transmissive layer, making it difficult to visually recognize the welded portion.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] However, in the display device of Patent Document 1, the semi-transmissive layer may inhibit the fusion bonding of the protective panel member and the case member during laser welding, and there is room for improvement.

[0005] Therefore, an object of the present disclosure is to provide a display device that can increase the bonding strength of a welded portion while making the welded portion difficult to visually recognize.

Means for Solving the Problems

[0006] On one side, the following solution means are provided. A protective panel member made of a light-transmissive plate member and having a light-shielding region formed by a light-transmissive region and a light-shielding printing layer, A display disposed on the back side of the protective panel member and displaying information through the light-transmissive region, The protective panel member is provided with a case member positioned on the rear side so as to surround the display and supporting the rear portion of the outer periphery of the protective panel member. A display device in which the outer peripheral back portion of the protective panel member and the case member are joined by laser welding, The color of the printed layer is the same as or similar to the color of the case component. The outer periphery of the protective panel member has a non-printed area where the printed layer is not formed, corresponding to the laser welding bonding area. The outer surface portion of the protective panel member has a flat surface, a tapered surface, or a curved surface in the region facing the welded portion formed by laser welding. [Effects of the Invention]

[0007] According to this disclosure, it is possible to make the welded area difficult to see while increasing the joint strength of the welded area. [Brief explanation of the drawing]

[0008] [Figure 1] This is a schematic front view of a display device according to an embodiment of the present disclosure. [Figure 2] This is a schematic cross-sectional view of AA in Figure 1. [Figure 3] Figure 1 is an enlarged cross-sectional view of the main part of the BB. [Figure 4] This is an enlarged cross-sectional view of the main part of the display device according to the first modified example of this disclosure. [Figure 5] This is an enlarged cross-sectional view of the main part of the display device according to the second modified example of this disclosure. [Figure 6] This is an enlarged cross-sectional view of the main part of the display device according to the third modified example of this disclosure. [Figure 7] This is an enlarged cross-sectional view of the main part of the display device according to the fourth modified example of this disclosure. [Figure 8] This is an enlarged cross-sectional view of the main part of the display device according to the fifth modified example of this disclosure. [Modes for carrying out the invention]

[0009] Hereinafter, embodiments will be described in detail with reference to the accompanying drawings.

[0010] (Configuration of Display Device) The display device 100 according to an embodiment of the present disclosure will be described with reference to FIGS. 1 to 3. The display device 100 is mounted on a vehicle (automobile, motorcycle, agricultural machine, construction machine, etc.) and is configured as an instrument device that displays information such as vehicle speed.

[0011] In the following, in order to facilitate the understanding of the configuration of the display device 100, for each member, the direction of looking at the user sitting in the vehicle driver's seat from the display device 100 is defined as "front (front face)", and the opposite side is defined as "rear".

[0012] The display device 100 includes a protection panel member 1, a display 2 and a circuit board 3 disposed on the back side of the protection panel member 1, and a case member 4 that supports the protection panel member 1 so as to surround the display 2 on the back side of the protection panel member 1 and houses the display 2 and the circuit board 3.

[0013] The protection panel member 1 has a light-transmitting (including transparent and translucent) plate member 1a as a base material, and has a light-transmitting region 1b and a light-shielding region 1c. The plate member 1a serving as the base material is made of a resin such as acrylic resin or polycarbonate resin. Note that the protection panel member 1 is disposed on the front side of the display 2 so as to cover (protect) the display 2.

[0014] The light-shielding region 1c is formed by a light-shielding printing layer 1e applied to the back surface portion 1d on the outer peripheral side of the protection panel member 1. The color of the printing layer 1e is the same color or a similar color to the color of the case member 4. For example, when the color of the case member 4 is black, the printing layer 1e is formed using black ink.

[0015] The light-transmitting region 1b is formed inside the light-shielding region 1c. The light-transmitting region 1b is a region that does not have the printing layer 1e formed and retains the light-transmitting property of the plate member 1a, and has, for example, a horizontally long rectangular shape.

[0016] The back surface portion 1d on the outer peripheral side of the protection panel member 1 is joined to the case member 4 by laser welding. Laser welding will be described later.

[0017] The display 2 is a display such as a liquid crystal panel that displays various vehicle information. The display state (display content) of the display 2 is controlled by a control unit (such as a vehicle ECU (Electronic Control Unit)) not shown in the figure. The various vehicle information displayed by the display 2 is, for example, vehicle speed, engine speed, accumulated mileage, remaining mileage, average fuel consumption, the situation of other surrounding vehicles, and the like.

[0018] The display 2 has a horizontally long rectangular shape with an outer shape as large as the light-transmitting region 1b when viewed from the user (front), and is arranged on the back side of the protection panel member 1 so as to face the light-transmitting region 1b. Thereby, the display 2 is visually recognized by the driver through the light-transmitting region 1b of the protection panel member 1.

[0019] The display 2 is provided with a backlight (not shown) that transmits illumination from the back side. The backlight has a light-emitting body such as a light-emitting diode, an optical sheet such as a diffusion plate or a prism sheet, and a light guide made of a transparent resin, and illuminates the display 2 evenly from the back side.

[0020] The circuit board 3 is composed of, for example, a rigid wiring board obtained by applying a wiring pattern (not shown) to a flat glass epoxy-based substrate, and supports the display 2. Various circuit components (not shown) are mounted on the circuit board 3, and a drive circuit for the display 2 is constituted by these circuit components and the wiring pattern.

[0021] The case member 4 is made of a synthetic resin (for example, ABS resin) having light absorption and thermoplasticity. The color of the case member 4 is the same color or a similar color to the color of the printing layer 1e. In the present embodiment, the case member 4 and the printing layer 1e are black.

[0022] The case member 4 has a box shape consisting of a bottom portion 4a and side wall portions 4b, with an opening 4c formed on the front side. A protective panel member 1 is joined to the front side of the case member 4 so as to close the opening 4c.

[0023] The bottom portion 4a is located on the back side of the circuit board 3. The side wall portion 4b rises from the outer periphery of the bottom portion 4a and is formed to surround the display unit 2 on the back side of the protective panel member 1. The front end of the side wall portion 4b has a joining surface 4d that is joined to the back portion 1d on the outer periphery side of the protective panel member 1 by laser welding.

[0024] (Laser welding) Next, the laser welding process mentioned above will be explained with reference to Figure 3.

[0025] The outer rear surface 1d of the protective panel member 1 and the joining surface 4d of the case member 4 are joined by laser welding. Laser light is shone from the front side of the protective panel member 1 toward the joining surface 4d of the case member 4. The joining surface 4d of the case member 4 absorbs the laser light and generates heat, and this heat melts and bonds the joining region S of the case member 4 and the protective panel member 1. When solidified, a welded portion Y is formed. As a result, the outer rear surface 1d of the protective panel member 1 and the joining surface 4d of the case member 4 are joined via the welded portion Y.

[0026] The laser beams used for laser welding include YAG lasers, diode lasers, fiber lasers, and infrared lasers. The laser beam moves along the longitudinal direction of the joining region S (the direction of the outer circumference of the protective panel member 1) and is irradiated onto the joining region S with a predetermined laser irradiation diameter R.

[0027] The outer rear portion 1d of the protective panel member 1 has a non-printed area 1f where the printed layer 1e is not formed, at a position corresponding to the joint area S formed by laser welding. Not only is the light-shielding printed layer 1e absent in the non-printed area 1f, but also the transparent and semi-transparent printed layers.

[0028] The unprinted area 1f has a strip shape with a predetermined width W. Furthermore, the predetermined width W is set to be narrower than the laser irradiation diameter R for laser welding. With this configuration, when laser light is irradiated from the front side to the back side of the protective panel member 1 during the laser welding described above, the laser light that has passed through the unprinted area 1f is irradiated onto the joint surface 4d of the case member 4. The joint surface 4d of the case member 4 absorbs the laser light and generates heat, and this heat melts and bonds the joint area S of the case member 4 and the protective panel member 1. At this time, since the printed layer 1e is not interposed between the case member 4 and the protective panel member 1 in the joint area S, the melt bonding between the case member 4 and the protective panel member 1 is not hindered by the printed layer 1e, and the bonding strength of the welded part Y can be increased.

[0029] Furthermore, since the width W of the unprinted area 1f is set to be narrower than the laser irradiation diameter R, during laser welding, the unprinted area 1f is melted and bonded with the case member 4 over a wide area, forming a band-shaped welded area Y that exhibits a nearly uniform black color. Moreover, since the welded area Y is formed without gaps with the adjacent black printed layer 1e on the inside, the welded area Y and the printed layer 1e appear as one, making the welded area Y difficult to see.

[0030] Furthermore, the outer peripheral side portion 1j of the protective panel member 1 is a tapered surface that is inclined so as to be located further outward towards the surface portion 1g. This allows the laser beam to reach the outer peripheral edge of the back portion 1d of the protective panel member 1 during laser welding, enabling the entire unprinted area 1f to be melted and bonded with the case member 4. As a result, the back portion 1d of the protective panel member 1 can exhibit a nearly uniform black color due to the welded portion Y formed by laser welding, even without forming a printed layer 1e on the outer peripheral side of the unprinted area 1f. In addition, not forming a printed layer 1e on the outer peripheral side of the unprinted area 1f has the advantage of allowing the thickness of the side wall portion 4b of the case member 4 to be reduced.

[0031] Furthermore, the outer surface portion (front portion) 1g of the protective panel member 1 has a tapered surface 1h in the region facing the welded portion Y, which is inclined to recede further outward from the surface portion 1g of the light-transmitting region 1b. In this way, the tapered surface 1h promotes external light reflection from the perspective of a user viewing the display device 100 (display unit 2), making it even more difficult to see the state of the welded portion Y.

[0032] (modified version) Next, a modified example of the above-described embodiment will be explained with reference to Figures 4 to 8. However, for components common to the above-described embodiment, the same reference numerals as in the above-described embodiment may be used, and the explanation of the above-described embodiment may be referred to.

[0033] Figure 4 is an enlarged cross-sectional view of the main part of the display device 100 according to the first modified example of this disclosure. As shown in Figure 4, the protective panel member 1 of the display device 100 according to the first modified example differs from the previously described embodiment in that, in the region where the tapered surface 1h of the previously described embodiment is formed, a curved surface 1i is provided instead of the tapered surface 1h. Even with this first modified example, the state of the welded portion Y can be made difficult to see based on an optical effect substantially equivalent to that of the previously described embodiment.

[0034] Figure 5 is an enlarged cross-sectional view of the main part of the display device 100 according to the second modified example of this disclosure. As shown in Figure 5, the protective panel member 1 of the display device 100 according to the second modified example differs from the previously described example in that the area where the tapered surface 1h is formed is made flat instead of forming the tapered surface 1h. Even this second modified example is included in the present invention.

[0035] Figure 6 is an enlarged cross-sectional view of the main part of the display device 100 according to the third modified example of this disclosure. As shown in Figure 6, the display device 100 according to the third modified example differs from the previously described embodiment in that the outer peripheral side portion 1j of the protective panel member 1 is a flat surface perpendicular to the back portion 1d of the protective panel member 1. Even with this third modified example, during laser welding, the laser light can be irradiated to the outer peripheral edge of the back portion 1d of the protective panel member 1, and the entire unprinted area 1f can be melted and bonded with the case member 4.

[0036] Figure 7 is an enlarged cross-sectional view of the main part of the display device 100 according to the fourth modified example of this disclosure. As shown in Figure 7, the display device 100 according to the fourth modified example differs from the previously described embodiment in that the outer peripheral side portion 1j of the protective panel member 1 is shaped to protrude outward in a V-shape. Even with this fourth modified example, the laser light can be irradiated to the outer peripheral edge of the back portion 1d of the protective panel member 1 during laser welding, and the entire unprinted area 1f can be melted and bonded with the case member 4.

[0037] Figure 8 is an enlarged cross-sectional view of the main part of the display device 100 according to the fifth modified example of this disclosure. As shown in Figure 8, the protective panel member 1 of the display device 100 according to the fifth modified example differs from the previously described embodiment in that it has an uneven pattern 1k in the region (tapered surface 1h, curved surface 1i, etc.) of the surface portion 1g facing the welded portion Y. The uneven pattern 1k is, for example, a texture such as matte, carbon fiber, metallic, or leather. According to this fifth modified example, the uneven pattern 1k generates diffuse reflection of light, making it even more difficult to see the state of the welded portion Y.

[0038] Furthermore, the protective panel member 1 of the display device 100 according to the fifth modified example also has an uneven pattern 1k on the outer peripheral side portion 1j. In this way, the uneven pattern 1k also causes diffuse reflection of light on the side portion 1j, making it even more difficult to see the state of the welded portion Y. Note that the uneven pattern 1k may be formed only in the region of the surface portion 1g facing the welded portion Y, or it may be formed only on the side portion 1j.

[0039] Although each embodiment has been described in detail above, the invention is not limited to any particular embodiment, and various modifications and changes are possible within the scope described in the claims. Furthermore, it is possible to combine all or more of the components of the embodiments described above.

[0040] The present invention includes the following embodiments. [1] A protective panel member consisting of a translucent plate member and having a translucent region and a light-shielding region formed by a light-shielding printed layer, A display unit is positioned on the back side of the protective panel member and displays information through the light-transmitting area, The protective panel member is provided with a case member positioned on the rear side so as to surround the display and supporting the rear portion of the outer periphery of the protective panel member. A display device in which the outer peripheral back portion of the protective panel member and the case member are joined by laser welding, The color of the printed layer is the same as or similar to the color of the case component. The outer periphery of the protective panel member has a non-printed area where the printed layer is not formed, corresponding to the laser welding bonding area. A display device wherein the outer surface portion of the protective panel member has a flat surface, a tapered surface, or a curved surface in the region facing the laser-welded portion. [2] The display device according to [1], wherein the width of the unprinted area is set to be narrower than the laser irradiation diameter of the laser welding. [3] The display device according to [1] or [2], wherein the back portion on the outer periphery side of the protective panel member does not have the printed layer on the outer periphery side of the unprinted area. [4] The display device according to any one of [1] to [3], wherein the outer peripheral side of the protective panel member is a flat surface perpendicular to the back surface of the protective panel member, or a tapered surface located further outward towards the front surface. [5] The display device according to any one of [1] to [4], wherein the outer surface of the protective panel member has an uneven pattern in the region facing the welded portion by laser welding. [6] The display device according to any one of [1] to [5], wherein the outer peripheral side portion of the protective panel member has an uneven pattern. [Explanation of Symbols]

[0041] 100 display device 1. Protective panel component 1a Plate member 1b Translucent area 1c Shading area 1d Back part 1e printing layer 1f No printing area 1g surface area 1h Tapered surface 1i curved surface 1j Side part 1k textured surface 2 Display 3 Circuit board 4 Case components 4a Bottom part 4b Side wall part 4c opening 4d joint surface Y welded part S junction area R Laser irradiation diameter W width of the area without printing

Claims

1. A protective panel member consisting of a translucent plate member, having a translucent region and a light-shielding region formed by a light-shielding printed layer, A display unit is positioned on the back side of the protective panel member and displays information through the light-transmitting area, The protective panel member is provided with a case member positioned on the rear side so as to surround the display and supporting the rear portion of the outer periphery of the protective panel member. A display device in which the outer peripheral back portion of the protective panel member and the case member are joined by laser welding, The color of the printed layer is the same as or similar to the color of the case component. The outer periphery of the protective panel member has a non-printed area where the printed layer is not formed, corresponding to the laser welding bonding area. A display device wherein the outer surface portion of the protective panel member has a flat surface, a tapered surface, or a curved surface in the region facing the laser-welded portion.

2. The display device according to claim 1, wherein the width of the non-printed area is set to be narrower than the laser irradiation diameter of the laser welding.

3. The display device according to claim 1, wherein the back portion on the outer periphery side of the protective panel member does not have the printing layer on the outer periphery side of the unprinted area.

4. The display device according to claim 1, wherein the outer peripheral side surface of the protective panel member is a flat surface perpendicular to the back surface of the protective panel member, or a tapered surface located further outward towards the front surface.

5. The display device according to claim 1, wherein the outer surface portion of the protective panel member has an uneven pattern in the region facing the welded portion formed by laser welding.

6. The display device according to claim 1, wherein the outer peripheral side portion of the protective panel member has an uneven pattern.

Images