Case

Abstract

To provide a vehicle display device having improved electromagnetic compatibility.SOLUTION: A head-up display device 100 including an example of a case includes: a lower case 60b that is an example of a main body part that forms a flat part 60bf for holding a circuit board 80; and a shield 70 is formed in a box shape with an opening and covers a circuit board 80. The shield 70 has screw holes 740 formed therein, and has ends 731, 732, 733, 734 (bent parts 731a, 732a, 733a, 734a) that contact the flat part 60bf when screwed to the lower case 60b by screws 8 inserted through the screw holes 740. The ends 731, 732, 733, 734 form the screw holes 740, and between the screw holes 740 are bent parts 731a, 732a, 733a, 734a that have a convex shape toward the flat part 60bf.SELECTED DRAWING: Figure 2

Description

[Technical field]

[0001] The present invention relates to a case. [Background technology]

[0002] Conventionally, a configuration such as that shown in Patent Document 1 has been disclosed. The circuit board (ground structure) disclosed in this document includes a noise ground layer (140) that transmits noise generated by a noise source (200), and a circuit ground layer (100) for a power supply supplied to electronic components. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2015-111642 A Summary of the Invention [Problem to be solved by the invention]

[0004] However, even with this configuration, there is still room for improvement in terms of resistance to external noise (immunity, electromagnetic susceptibility, EMS) and noise emission (electromagnetic interference, EMI). In particular, high electromagnetic compatibility (EMC) is required around connectors that connect high-speed signal lines used for transmitting and receiving video and other signals.

[0005] SUMMARY OF THE PRESENT EMBODIMENT In view of the above, an object of the present invention is to provide a case having improved electromagnetic compatibility (EMC performance). [Means for solving the problem]

[0006] In order to achieve the above object, the case according to the present invention comprises: a main body portion forming a flat surface for holding a circuit board; a box-shaped shield having an opening and covering the circuit board; Equipped with the shield has a plurality of holes formed therein, and an end portion that contacts the flat surface by being screwed to the body portion by screws inserted through the holes; The end portions define the holes, and the portions between the holes have a convex shape facing the plane. [Brief description of the drawings]

[0007] [Figure 1] 1 is a diagram showing an example of a state in which a head-up display 100 (HUD 100) according to the present disclosure is mounted on a vehicle. [Diagram 2] A diagram showing the appearance of HUD100. [Diagram 3] 1 is a diagram showing the appearance of the underside of the HUD 100. [Figure 4A] FIG. 4 is a perspective view showing the appearance of the shield 70 from the top side. [Figure 4B] FIG. 4 is a perspective view showing the appearance of a shield 70 from the end side. [Figure 5A] FIG. 2 is a diagram showing the appearance of a shield 70 from a viewpoint opposite to a side surface 711. [Figure 5B] 13 is a cross-sectional view showing a state in which the shield 70 is screwed to the lower case 60b. FIG. [Figure 6A] FIG. 9 is a diagram showing the appearance of the shield 90 from a viewpoint opposite to a side surface 911. [Figure 6B] 13 is a cross-sectional view showing a state in which the shield 90 is screwed to the lower case 60b. FIG. [Figure 7] FIG. 2 is a diagram showing the appearance of a shield 71. [Figure 8] FIG. 4 is a diagram showing the appearance of a shield 72. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0008] One embodiment of the case of the present disclosure will be described with reference to the drawings as a configuration included in a head-up display device. [First embodiment] <1-1. Overall structure> <1-2. About Shield 70> [effect] [Variations]

[0009] 1, the head-up display device 100 is installed in the dashboard of a vehicle 200. The head-up display device 100 emits display light L that displays an image toward a windshield 201, which is an example of a projection target member of the vehicle 200. The display light L is reflected by the windshield 201 and reaches a viewer 1 (mainly the driver of the vehicle 200). As a result, a virtual image V is displayed so as to be visible to the viewer 1.

[0010] 2, the head-up display device 100 includes an illumination unit 40, a display unit 10, a concave mirror 30, a housing 60, a shield 70, and a circuit board 80. In the following description, the vehicle width direction is defined as the X direction, the vehicle height direction is defined as the Y direction, and the vehicle front-rear direction is defined as the Z direction.

[0011] The illumination unit 40 is a light box that irradiates illumination light IL onto the display unit 10. In this example, the illumination light IL travels along the Z-axis direction.

[0012] The display unit 10 receives illumination light IL from the illumination unit 40 and emits display light L that displays an image. The display unit 10 includes a display panel 14, an optical element 17, a hot mirror 19, and a display unit case 15 that houses the display panel 14 and the optical element 17. The display unit case 15 includes a display panel holder 12 and a display panel cover 11.

[0013] The display panel 14 is a TFT (Thin Film Transistor) type liquid crystal display panel controlled by a circuit board 80. The display panel 14 receives illumination light IL from the illumination unit 40 and emits display light L. The optical element 17 is made up of a prism for adjusting the display light L from the display panel 14, a diffusion plate, and the like.

[0014] The display panel holder 12 has a generally rectangular cylindrical shape and surrounds the outer periphery of the display panel 14 and the optical element 17. The display panel holder 12 accommodates the display panel 14 and the optical element 17. The display panel cover 11 is formed so as to be attachable to the display panel holder 12 so as to cover the display panel holder 12 from the side of the illumination unit 40. The display panel cover 11 has a cylindrical frame shape through which the illumination light IL passes.

[0015] The concave mirror 30 reflects the display light L from the display unit 10 toward the windshield 201 while magnifying the light.

[0016] The housing 60 is made of non-translucent resin or metal and is a hollow rectangular parallelepiped. Each component of the head-up display device 100 is housed inside the housing 60. In detail, the housing 60 includes an upper case 60a, a lower case 60b, a blind cover 62, a display unit cover 60d, a heat sink 60g, and a shield 70.

[0017] The lower case 60b is an example of a main body and has a box shape that opens upward. The lower case 60b is formed with an optical path space 60s that houses the concave mirror 30, and a storage space 60f that houses the display unit 10 and the illumination unit 40. A through hole 60h through which the display light L from the display unit 10 passes is formed in a side wall of the lower case 60b located between the optical path space 60s and the storage space 60f. The heat sink 60g is integrally formed with the lower case 60b, and is located on the rear surface of a light source substrate 41 (described later), forming a fin structure that dissipates heat from the light source substrate 41 to the outside. The heat sink 60g may be formed as a cover separate from the lower case 60b. The lower case 60b forms a flat surface 60bf on the lower surface of the bottom surface of the optical path space 60s. The flat surface 60bf holds a circuit board 80, which will be described later. The flat surface 60bf forms screw holes 60i into which screws inserted into holes in the circuit board and holes 740 in the shield 70 are screwed. The lower case 60b is configured as a case that houses the circuit board 80 by being combined with the shield 70, which will be described later.

[0018] A plurality of screw holes 60i (see FIG. 7) are provided in the housing space 60f of the lower case 60b. Each screw hole 60i has a cylindrical shape extending in the Y direction, and a screw hole is formed in the lower end surface (upper end surface in FIG. 7) of the screw hole 60i. The shank of a screw can be screwed into the screw hole of the screw hole 60i.

[0019] The upper case 60a functions as a lid that closes the optical path space 60s of the lower case 60b from above. An opening 61 is formed in the upper case 60a at a position facing the windshield 201. The upper case 60a has a curved plate-like window portion 50 that closes the opening 61. The window portion 50 is made of a translucent resin such as acrylic that transmits the display light L.

[0020] The blind cover 62 is provided between the through-hole 60h of the lower case 60b and the display unit 10, and has a cylindrical shape that guides the display light L emitted by the display unit 10 to the through-hole 60h. The blind cover 62 is attached to the light emission side of the display panel holder 12. A hot mirror 19 is provided between the blind cover 62 and the display panel holder 12.

[0021] The display unit cover 60d is attached to the lower case 60b so as to cover the accommodation space 60f of the lower case 60b. The shield 70 is attached to the outer bottom surface of the lower case 60b so as to cover the circuit board 80 placed on the outer bottom surface (flat surface portion 60bf) of the lower case 60b. The shield 70 houses the circuit board 80 in an internal housing space S. A detailed configuration of the shield 70 will be described later. The shield 70 is configured as a case that houses the circuit board 80 by being combined with the lower case 60b.

[0022] The circuit board 80 is made of a printed circuit board on which various electronic components such as a CPU (Central Processing Unit) are mounted, and controls the display unit 10 and the illumination unit 40.

[0023] As shown in FIG. 2, the illumination unit 40 includes a plurality of light sources 41a, a light source substrate 41 on which the plurality of light sources 41a are mounted, a plurality of lenses 42a, 42b, and 42c that adjust the illumination light from the light source 41a, and a lens holder 20 that houses the plurality of lenses 42a, 42b, and 42c.

[0024] The light source substrate 41 and the lenses 42a, 42b, and 42c are arranged facing each other and aligned in the Z direction. The light source substrate 41 is provided at a position in direct contact with the heat sink 60g or indirectly contacts the heat sink 60g via a thermal sheet (not shown) so that heat can be dissipated to the heat sink 60g. A plurality of light sources 41a are mounted on a mounting surface of the light source substrate 41 facing the lens 42a. The light sources 41a are LEDs (Light Emitting Diodes) and emit illumination light IL. As shown in FIG. 9, the light source substrate 41 is provided in a direction inclined with respect to the direction of the central axis J of the screw 8.

[0025] 2, the lens 42a is a condenser lens that approximately collimates the illumination light IL. The lenses 42b and 42c are lenticular lenses that diffuse the illumination light IL in the X and Y directions so as to distribute the display light L to the eyebox.

[0026] The lens holder 20 is a cylindrical member made of resin that surrounds the periphery of the light source substrate 41 and the lenses 42a, 42b, and 42c. The lens holder 20 is formed by injection molding using a pair of molds.

[0027] <1-2. About Shield 70> The configuration of the shield 70 will be described with reference to FIGS. 3 to 6B. 3, the shield 70 is held by being fixed to the flat portion 60bf of the lower case 60b with screws 8. The shield 70 covers the circuit board 80 while accommodating the circuit board 80 in an internal accommodation space S. In this way, the shield 70 blocks electromagnetic waves emitted by the circuit board 80 and blocks electromagnetic waves irradiated to the circuit board 80.

[0028] As shown in Fig. 4A and Fig. 4B, the shield 70 is in the shape of a box having an opening. The shield 70 has a top surface 701, which is a flat surface that fits along the circuit board 80, side surfaces 711, 712, 713, 714 formed from the edge of the top surface 701 toward the flat surface portion 60bf, end portions 721, 722, 723, 724 formed so that the edge formed by the side surfaces 711, 712, 713, 714 comes into contact with the flat surface portion 60bf, bent portions 731, 732, 733, 734 forming part of the end portions 721, 722, 723, 724, and a screw hole 740 formed in part of the end portions. The shield 70 is fixed to the flat surface portion 60bf by a screw 8 inserted into the screw hole 740. The screw 8 is screwed into the screw hole 60i through the screw hole 740.

[0029] 4A, 4B, and 5A, the shield 70 comes into contact with the flat portion 60bf particularly at bent portions 731, 732, 733, and 734 that are convex toward the flat portion 60bf. Specifically, the bent portions 731, 732, 733, and 734 are convex toward the flat portion 60bf across the spaces between the screw holes 740. The bent portions 731, 732, 733, and 734 extend beyond the reference lines 731a, 732a, 733a, and 734a to form a convex shape. The reference lines 731a, 732a, 733a, and 734a are defined as the lines closest to the flat portion 60bf among the lines generated by the intersection of planes parallel to the flat portion 60bf over the entire circumference within the side surfaces 711, 712, 713, and 714.

[0030] The shield 70 thus configured, when screwed, can be in firm contact with the flat portion 60bf as shown in FIG. 5B, and exhibits high EMC performance.

[0031] For comparison with the present invention, a conventional configuration is shown in Figures 6A and 6B. Shield 90 forms bent portion 931 at the edge of side surface 911. When not screwed, shield 90 has a shape parallel to flat surface portion 60bf and does not have a convex shape. The configuration of shield 90 other than the bent portion (particularly the top surface and side surfaces) is similar to the configuration of shield 70. That is, shield 90 is also box-shaped with an opening, and bent portions similar to bent portion 931 are formed at each edge of the side surfaces.

[0032] 6B shows a state in which the shield 90 is screwed in place. The bent portion 931 of the shield 90 may be distorted by the tightening of the screw 8, causing a gap C between the bent portion 931 and the flat portion 60bf. When two components (the shield 90 and the flat portion 60bf) that are similar in shape when not screwed in place are screwed in this way, considerable deformation occurs, and the contact between the two is partially weakened or lost.

[0033] Depending on the case, the gap C may be large enough to be seen with the naked eye, or it may be so small that it cannot be seen with the naked eye but is large enough that electromagnetic waves can pass through. However, in either case, a configuration in which such a gap C occurs may have a large increase or decrease in EMC performance due to individual differences. Thus, EMC performance varies greatly depending on the contact between the shield and the body.

[0034] In this regard, in the configuration including the shield 70 of the present disclosure, the bent portions 731, 732, 733, 734 are formed at the ends 721, 722, 723, 724 that contact the flat portion 60bf, so that the shield 70 comes into firm contact with the flat portion 60bf and can stably exhibit high EMC performance.

[0035] In particular, it is desirable that the shield 70 be made of a harder material than the lower case 60b. For example, if the shield 70 is made of iron and the lower case 60b is made of magnesium, the bent portions 731, 732, 733, 734 and the ends 721, 722, 723, 724 will bite into the flat portion 60bf, achieving more reliable contact.

[0036] [effect] According to the embodiment described above, the following effects are achieved. (1) A head-up display device 100 including an example of a case, A lower case 60b, which is an example of a main body portion that forms a flat portion 60bf for holding a circuit board 80; A shield 70 having a box shape with an opening and covering a circuit board 80; Equipped with The shield 70 has a screw hole 740 formed therein, and has ends 721, 722, 723, 724 (bent portions 731, 732, 733, 734) that come into contact with the flat portion 60bf by being screwed to the lower case 60b by a screw 8 inserted through the screw hole 740, The end portions 721, 722, 723, and 724 form screw holes 740, and bent portions 731, 732, 733, and 734 that are convex toward the flat portion 60bf are formed between the screw holes 740. According to this configuration, the case can stably exhibit high EMC performance by firmly establishing contact between the shield 70 and the lower case 60b in a screwed state.

[0037] The present disclosure is not limited to the above-described embodiments and drawings. Modifications (including deletion of components) can be made as appropriate within the scope of the present disclosure. An example of a modification will be described below.

[0038] [Variations] In the first embodiment, an example has been shown in which the case is configured by combining the shield 70 and the lower case 60b, but other configurations may be adopted for these.

[0039] For example, a shield 71 shown in FIG. 7 may be used for the lower case 60b. The shield 71 has a flange-shaped end 720 instead of the ends 721, 722, 723, and 724 of the shield 70. The end 720 also has bent portions 731, 732, 733, and 734 like the shield 70. The screw holes 740 may be formed in the four corners of the end 720. Even in this configuration, the bent portions 731, 732, 733, and 734 have a convex shape, so that good contact with the flat portion 60bf can be achieved. Such a shield 71 can be formed, for example, by pressing a flat iron plate.

[0040] 8 may be used for the lower case 60b. The shield 72 is composed of a top surface 702, side surfaces 715, and end portions 751, 752, 761, 762, and 763. Compared to the top surface 701 and side surfaces 711, 712, 713, and 714 of the shield 70, the top surface 702 and side surfaces 715 have a shape in which the four corners are cut off and the side surfaces are reconnected. End portions 761, 762, and 763 are formed in the spaces in the four cut-off corners, and screw holes 740 are also formed.

[0041] The side surface 715 has ends 751, 752 at its edge, which are convex toward the flat surface portion 60bf. Even in this configuration, the ends 751, 752 extend beyond the reference lines 751a, 752a to form a convex shape, as in the shield 70. The reference lines 751a, 752a are defined as the lines closest to the flat surface portion 60bf among the lines generated by the intersection of planes parallel to the flat surface portion 60bf over the entire circumference within the side surface 715.

[0042] In the above embodiment, the head-up display device 100 may include a folding mirror that reflects the display light L from the display unit 10 toward the concave mirror 30. The folding mirror is a plane mirror or a concave mirror.

[0043] In the above embodiment, the head-up display device 100 is mounted on the vehicle 200, but may be mounted on a vehicle other than the vehicle 200, such as an airplane or a ship. The projection member is not limited to the windshield, and may be a dedicated combiner. The case may be included in another device equipped with a circuit board. [Explanation of symbols]

[0044] 1. Viewer 10 Display 11 Display panel cover 12 Display panel holder 14 Display Panel 15 Display case 17 Optical elements 19 Hot Mirror 20 Lens holder 30 concave mirror 40 Lighting Department 41 Light source board 41a light source 42a, 42b, 42c Lenses 50 Window 60 Case 60a Upper case 60b Lower case (an example of the main body) 60bf flat part 60d Display cover 60e Board cover 60f Storage space 60g heatsink 60s optical path space 61 Opening 62 Blind Cover 70,71,90 Shield 701,702 Top 711,712,713,714,715,911 Side 720,721,722,723,724,751,752,761,762,763 Ends (including convex shapes) 731, 732, 733, 734 Folded part (example of convex shape) 731a,732a,733a,751a,752a Reference straight line 740 screw hole 8 screws 80 Circuit Board 100 Head-up display device 200 vehicles 201 Windshield L display light V Virtual Image IL illumination light C space

Claims

[Claim 1] a main body portion forming a flat surface for holding a circuit board; a box-shaped shield that defines an opening and covers the circuit board; Equipped with the shield has a plurality of holes formed therein, and an end portion that contacts the flat surface by being screwed to the body portion by screws inserted through the holes; The end portion forms the hole, and the portion between the holes forms a convex shape toward the plane. case.

Images