In-vehicle display device

Abstract

To provide an in-dash or on-dash on-vehicle display device with excellent impact resistance of a cover glass.SOLUTION: An on-vehicle display device has n layers from a cover glass 2 to a casing bottom member 5 and has at least a display panel 3 midway. The casing bottom member 5 comprises only a casing bottom plate 6, or the casing bottom plate 6 and a rib 7. The casing bottom member 5 is fixed to an interior part 10 of a vehicle at least at two points. When a virtual plane passing through an intermediate point Q between the two points and perpendicular to a line connecting the two points is denoted by R, a length of an intersection line between a main surface of the cover glass 2 and the virtual plane R is denoted by Zcg, and a length from an upper end to a point corresponding to the intermediate point Q among an intersection line between the main surface of the display panel 3 and the virtual plane R is denoted by Z, a ratio Z / Zcg is 0.6 or less. On a virtual line L passing in the thickness direction of the in-vehicle display device 1 from an upper end of the intersection line between the virtual plane R and the main surface of the display panel 3 to 5 mm at the lower end side, a specific equation (1) is satisfied from the cover glass 2 to the casing bottom member 5.SELECTED DRAWING: Figure 2

Description

[Technical field]

[0001] The present invention relates to an in-vehicle display device. [Background technology]

[0002] 2. Description of the Related Art Conventionally, there is an in-vehicle display device having a display panel and a cover glass. As described in Patent Document 1, "from the standpoint of safety, the cover glass of an in-vehicle display device must have excellent impact resistance so that it will not break even if an occupant's head or other parts of the body hit it in the event of a vehicle collision" (

[0005] ).

[0003] In Patent Document 1, an in-vehicle display device having a cover glass is described as having the formula (I) P≦0.0302t1 2 It is described that by satisfying "+0.0039t1+0.0478", the cover glass has excellent impact resistance (

[0007] to

[0008] ). The P value in this "formula (I)" can be said to be an index indicating the rigidity of the in-vehicle display device. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] International Publication No. 2016 / 027812 Summary of the Invention [Problem to be solved by the invention]

[0005] An in-vehicle display device typically has a housing bottom member that constitutes a housing that houses each component of the in-vehicle display device. The housing bottom member is fixed to an interior portion (such as a dashboard) of a vehicle via a fixing member such as a bracket.

[0006] There are two types of in-vehicle display devices: a "standing type" in which only the lower end of the bottom member of the housing is fixed to the dashboard, and an "in-dash type" or "on-dash type" in which the upper end of the bottom member of the housing is also fixed to the dashboard. In the following, for convenience, the "in-dash type or on-dash type" will be collectively referred to simply as the "in-dash type".

[0007] Patent Document 1 substantially discloses only a standing type in-vehicle display device (see FIG. 4 of Patent Document 1). In-dash type vehicle-mounted display devices protrude less from the dashboard than standing type vehicle-mounted display devices, are more firmly fixed, and tend to have lower shock absorption properties. For this reason, the range of rigidity required for the cover glass to exhibit good impact resistance in the in-dash type vehicle-mounted display device may differ from that in the standing type. In other words, there are cases where simply satisfying "formula (I)" described in Patent Document 1 is insufficient.

[0008] In recent years, a housing bottom member having ribs is sometimes used for the purpose of weight reduction, etc., and this point must also be taken into consideration when examining the rigidity of the in-vehicle display device.

[0009] The present invention has been made in view of the above points, and has an object to provide an in-dash or on-dash type vehicle-mounted display device having a cover glass with excellent impact resistance. [Means for solving the problem]

[0010] As a result of extensive investigations, the present inventors have found that the above object can be achieved by employing the following configuration, and have completed the present invention. That is, the present invention provides the following [1] to

[10] .

[0011] [1] An in-vehicle display device having n layers from a cover glass to a housing bottom member, and having at least a display panel in between, wherein each layer is made of only a plate-shaped member or the plate-shaped member and a rib, and the housing bottom member is fixed to the interior of the vehicle at at least two fixed points, and a virtual plane passing through the midpoint of the two fixed points and perpendicular to the line connecting the two fixed points is called a virtual plane R, and a distance Z is called the length of the intersection line between the main surface of the cover glass and the virtual plane R. cg , the length from the upper end to the point corresponding to the midpoint of the intersection line between the main surface of the display panel and the virtual surface R is defined as a distance Z, cg Ratio to Z / Z cg is 0.6 or less, and on a virtual line L that passes 5 mm below the upper end of the intersection line between the main surface of the display panel and the virtual plane R in the thickness direction of the in-vehicle display device, a distance from the cover glass to the housing bottom member satisfies formula (1) described below.

[0012] [2] An in-vehicle display device having n layers from a cover glass to a housing bottom member and having at least a display panel in between, wherein each layer is made of only a plate-shaped member or the plate-shaped member and a rib, and the housing bottom member is fixed to the interior of the vehicle at one fixed point, and a virtual plane that passes through the fixed point and includes the thickness direction and vertical direction of the cover glass at the fixed point is called a virtual plane R, and the length of the intersection line between the main surface of the cover glass and the virtual plane R is called a distance Z. cg , the length from the upper end of the intersection line between the main surface of the display panel and the virtual surface R to the point corresponding to the fixed point is defined as a distance Z, cg Ratio to Z / Z cg is 0.6 or less, and on a virtual line L that passes 5 mm below the upper end of the intersection line between the main surface of the display panel and the virtual plane R in the thickness direction of the in-vehicle display device, a distance from the cover glass to the housing bottom member satisfies formula (1) described below.

[0013] [3] The in-vehicle display device according to [1] or [2], wherein the housing bottom member is fixed to the interior portion using a bracket. [4] The in-vehicle display device according to any one of the above [1] to [3], wherein on the imaginary line L, a distance from the cover glass to the housing bottom member further satisfies formula (5) described below. [5] The in-vehicle display device according to any one of [1] to [4] above, wherein the cover glass is tempered glass having a compressive stress layer having a thickness of 10 μm or more, the cover glass has a thickness of 0.5 to 2.5 mm, the cover glass has a Young's modulus of 60 to 90 GPa, the display panel has a Young's modulus of 60 to 90 GPa, and the housing bottom member has a Young's modulus of 40 to 250 GPa. [6] The in-vehicle display device according to any one of [1] to [5] above, wherein in a head impact test in which an impactor is collided with an impact point P on the main surface of the cover glass through which the virtual line L passes, so that the impact energy is 152 J, the deceleration of the impactor is 50 G or more. [7] The in-vehicle display device according to any one of the above [1] to [6], satisfying the following formulas (6) and (7), where M is the mass of the in-vehicle display device per unit area of ​​the cover glass. [8] The in-vehicle display device according to any one of [1] to [7] above, wherein a side wall of the housing is provided at a position opposite to an end face of the display panel, and a distance d1 between the end face of the display panel and the side wall of the housing is 2 mm or less. [9] The in-vehicle display device according to any one of [1] to [8] above, wherein a distance d2 between an end of the display panel and a member closer to the housing bottom member than the display panel is 1 mm or less.

[10] The in-vehicle display device according to any one of [1] to [9], wherein on the imaginary line L, a distance from the cover glass to the housing bottom member satisfies formula (4A) described below. Effect of the Invention

[0014] According to the present invention, it is possible to provide an in-dash or on-dash type vehicle-mounted display device having a cover glass with excellent impact resistance. [Brief description of the drawings]

[0015] [Figure 1] FIG. 1 is a cross-sectional view showing an in-vehicle display device. [Diagram 2] FIG. 2 is a cross-sectional view taken along line AA in FIG. [Diagram 3] FIG. 3 is a schematic diagram of the housing bottom member as viewed from the rib side. [Figure 4] FIG. 4 is a schematic diagram showing the arrangement of the brackets. [Diagram 5] FIG. 5 is a cross-sectional view showing the housing bottom member. [Figure 6] FIG. 6 is a plan view that typically illustrates the rib of FIG. [Figure 7] FIG. 7 is a schematic diagram showing a rib in which the position of point p is different from that in FIG. [Figure 8] FIG. 8 is a schematic diagram showing horizontal ribs in addition to vertical ribs. [Figure 9] FIG. 9 is a schematic diagram showing a state in which the aligned ribs are not parallel to each other. [Figure 10] FIG. 10 is a schematic diagram showing a state in which a display panel is attached to a cover glass. [Figure 11] FIG. 11 is an enlarged cross-sectional view of the in-vehicle display device. [Figure 12] FIG. 12 is a schematic diagram showing a modified example of the in-vehicle display device. [Figure 13] FIG. 13 is a schematic diagram showing a rib having a trapezoidal cross-sectional shape. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0016] A numerical range expressed using "~" includes the numerical values ​​before and after "~" as the lower and upper limits.

[0017] Hereinafter, an embodiment of the present invention will be described with reference to the drawings. However, the present invention is not limited to the following embodiment. Various modifications and substitutions can be made to the following embodiment without departing from the scope of the present invention.

[0018] The in-vehicle display device according to the embodiment of the present invention has n layers from a cover glass to a housing bottom member, and has at least a display panel in between. Each layer is made of only a plate-shaped member, or the plate-shaped member and a rib. The housing bottom member is fixed to an interior part of a vehicle at at least two fixed points. A virtual plane passing through the midpoint between the two fixed points and perpendicular to a line connecting the two fixed points is called a virtual plane R. A distance Z is a length of an intersection line between the main surface of the cover glass and the virtual plane R. cg When the length from the upper end to the point corresponding to the midpoint of the intersection line between the main surface of the display panel and the imaginary surface R is defined as a distance Z, the distance Z and the distance Z cg Ratio to Z / Z cg is 0.6 or less, and on a virtual line L that passes through the thickness direction of the in-vehicle display device 5 mm below the upper end of the intersection line between the main surface of the display panel and the virtual plane R, a distance from the cover glass to the housing bottom member satisfies the formula (1) described below.

[0019] Alternatively, an in-vehicle display device according to an embodiment of the present invention is an in-vehicle display device having n layers from a cover glass to a housing bottom member, and having at least a display panel in the middle, and each layer is made of only a plate-shaped member, or the plate-shaped member and a rib, and the housing bottom member is fixed to an interior part of a vehicle at one fixed point, and a virtual plane that passes through the fixed point and includes the thickness direction and the vertical direction of the cover glass at the fixed point is called a virtual plane R, and the length of the intersection line between the main surface of the cover glass and the virtual plane R is called a distance Z. cg , the length from the upper end of the intersection line between the main surface of the display panel and the imaginary surface R to the point corresponding to the fixed point is defined as distance Z, and cg Ratio to Z / Z cg is 0.6 or less, and on a virtual line L that passes through the thickness direction of the in-vehicle display device 5 mm below the upper end of the intersection line between the main surface of the display panel and the virtual plane R, a distance from the cover glass to the housing bottom member satisfies the formula (1) described below.

[0020] 1 is a cross-sectional view showing an in-vehicle display device 1. Hereinafter, the "in-vehicle display device" may be simply referred to as the "display device". Fig. 2 is a cross-sectional view taken along the line AA in Fig. 1. Note that Fig. 2 omits illustration of lateral ribs 7 (ribs 75, 76, and 77) which will be described later. As will be described later, the in-vehicle display device 1 is an in-dash type or on-dash type in-vehicle display device. The in-vehicle display device 1 is, for example, a car navigation device, but may be another display device mounted on a vehicle, such as a display audio.

[0021] <Basic configuration> The in-vehicle display device 1 has a display panel 3 such as a liquid crystal panel and a cover glass 2 . The display panel 3 is attached to the cover glass 2 by an adhesive layer (not shown). The adhesive layer is, for example, an OCA (Optical Clear Adhesive) film or OCA tape, and its thickness is, for example, 5 to 400 μm, and preferably 50 to 200 μm. The in-vehicle display device 1 further has a housing bottom member 5 and housing side walls 8, which constitute the housing of the in-vehicle display device 1. A backlight unit 4, which is necessary when the display panel 3 is a liquid crystal panel, is disposed on the housing bottom member 5. Hereinafter, the "housing bottom member" may be simply referred to as the "bottom member".

[0022] In this way, the in-vehicle display device according to the embodiment of the present invention has a structure in which n layers are stacked from the cover glass to the housing bottom member. The in-vehicle display device according to the embodiment of the present invention has n layers from the cover glass to the housing bottom member, and has at least a display panel in between. In other words, the in-vehicle display device according to the embodiment of the present invention has an n-layer stacked structure including the housing bottom member, the display panel, and the cover glass in this order, the first layer of which is the cover glass, and the nth layer is the housing bottom member. n is an integer of 3 or more, and preferably 4 or more, while n is preferably 15 or less, and more preferably 12 or less.

[0023] For example, in the case of the in-vehicle display device 1 shown in Figures 1 and 2, four layers are stacked in this order: a cover glass 2 (first layer), a display panel 3 (second layer), a backlight unit 4 (third layer), and a housing bottom member 5 (fourth layer). In reality, an adhesive layer exists between the cover glass 2 (first layer) and the display panel 3 (second layer), but how to handle the adhesive layer will be described later.

[0024] The in-vehicle display device 1 does not necessarily have to include the backlight unit 4. Specifically, for example, the in-vehicle display device 1 may have a configuration in which three layers are stacked in this order: a cover glass 2 (first layer), a display panel 3 (second layer), and a housing bottom member 5 (third layer). In this case, an organic EL panel or the like that does not require a backlight unit 4 is selected as the display panel 3.

[0025] Moreover, each layer of the in-vehicle display device according to the embodiment of the present invention is made up of only a plate-like member, or a plate-like member and a rib. However, in the embodiment described below, an example will be described in which the member consisting of the plate-like member and the ribs is limited to the housing bottom member. In the case where a member separate from the housing bottom member is made up of a plate-like member and ribs, it may be treated in the same manner as the housing bottom member described below.

[0026] The housing bottom member 5 includes a housing bottom plate 6 which is a plate-like member. A plurality of ribs 7 are provided on the surface of the housing bottom plate 6 opposite to the cover glass 2. The ribs 7 are, for example, rectangular prism-shaped members. By forming the housing bottom member 5 in a shape having the ribs 7, the weight of the in-vehicle display device 1 can be reduced compared to a case where the housing bottom member 5 is formed in a thick plate shape without the ribs 7. The shape of the ribs 7 need not be linear, and may be curved.

[0027] Fig. 3 is a schematic diagram of the housing bottom member 5 as viewed from the side of the rib 7. In Fig. 3, brackets 9, which will be described later, and the like are omitted from the illustration. As shown in Fig. 3, in the housing bottom member 5 of this embodiment, a plurality of ribs 7 are arranged in a lattice pattern. Specifically, a plurality of ribs 7 extending in the up-down direction in Fig. 3, i.e., rib 71, rib 72, rib 73, and rib 74, intersect with a plurality of ribs 7 extending in the left-right direction in Fig. 3, i.e., rib 75, rib 76, and rib 77. However, the shape of the ribs 7 is not limited to that shown in Fig. 3 and may be any shape. For example, the ribs 7 may have a curved shape instead of a linear shape, and may not be arranged in a lattice pattern. The housing bottom member 5 does not necessarily have to have the rib 7. In this case, the housing bottom member 5 is made up of the housing bottom plate 6 only. The housing bottom member 5 may be integral with the housing side wall 8. The housing bottom member 5 may be formed by a method such as die casting or press molding.

[0028] <Fixing to vehicle interior parts> Next, with reference to Fig. 4 in addition to Figs. 1 to 3 described above, the fixing of the in-vehicle display device 1 (housing bottom member 5) to the interior part 10 of the vehicle will be described. Hereinafter, the "interior part of the vehicle" may be simply referred to as the "interior part". The interior part 10 is, for example, a part of the dashboard of the vehicle. Fig. 4 is a schematic diagram showing the arrangement of the bracket 9, in which the in-vehicle display device 1 (housing bottom member 5) is viewed from the interior part 10 (not shown in Fig. 4). In Fig. 4, the ribs 7 and the like are omitted.

[0029] The housing bottom member 5 is fixed to the interior part 10 of the vehicle at fixing points (fixing points P1 to P4) on the rear side (opposite side to the cover glass 2). That is, in FIG. 4, fixing points P are formed on the main surface of the bottom member 5 on the Z direction side (hereinafter, may be simply referred to as the "main surface of the bottom member 5"). The number of fixing points P is four in the example of FIG. 4, but the number may be arbitrary. The fixing points P (fixing points P1 to P4) are parts of the bottom member 5 that become interfaces fixed to the vehicle (to the interior part 10 in this embodiment), and are parts to which a bracket 9 described later can be attached in this embodiment. The X direction, Y direction, and Z direction in the following description of the fixing points P can be defined as follows. That is, as shown in FIG. 1 to FIG. 4, the thickness direction of the display device 1 and the direction from the display surface toward the rear side are defined as the Z direction. When the display device 1 is attached to the vehicle, the direction perpendicular to the Z direction and heading in one direction along the horizontal plane (rightward in the example of FIG. 1) is defined as the X direction. The direction perpendicular to the Z and X directions, which is perpendicular to the Z direction, is defined as the Y direction. Note that the "direction" of the Z, X, and Y directions is used as a concept that has a direction. In other words, when we say "Z direction," we mean the direction defined above, and when we say "the direction opposite to the Z direction," we mean the direction opposite to the direction defined above.

[0030] The bottom member 5 is fixed to the bracket 9 with its main surface on the Z direction side in contact with the fixed member (here, the bracket 9). If the area of ​​the main surface of the bottom member 5 that is in contact with the fixed member is defined as the contact area, the fixed point P can be a point on the contact area. The fixed point P can be any position on the contact area. For example, in FIG. 4, the fixed point P (fixed points P1 to P4) is exemplified as the midpoint position in the X direction of the side located on the Y direction side among the sides of each contact area. The fixed point P (fixed points P1 to P4) can be, for example, the midpoint position in the X direction of the side located on the opposite side to the Y direction among the sides of the contact area. It should be noted that one fixed point P is formed for each contact area. In other words, when there are multiple fixed points P, it can be said that multiple contact areas are formed at separate positions, and one fixed point is formed for each contact area. When there is one fixed point P, it can be said that there is also one contact area.

[0031] For example, when the in-vehicle display device 1 (casing bottom member 5) is fixed to the bracket 9, the fixing point P may be a position on the main surface of the bottom member 5 that overlaps with the midpoint of one side of the end of the convex surface 9a of the bracket 9 (i.e., the midpoint in the X direction of the side opposite to the Y direction of the contact area in the embodiment illustrated in Figs. 1 to 4). When the bottom member 5 is fixed to the bracket 9 with a fastener such as a bolt, the fixing point P may be a location on the main surface of the bottom member 5 where a hole (e.g., a bolt hole) into which the fastener is inserted is opened. Alternatively, when the bottom member 5 is fixed to the bracket 9 with a plurality of fasteners per contact area, the fixing point P may be a center position between the locations where the holes (e.g., bolt holes) into which the fasteners are inserted are opened. When the bottom member 5 is fixed to the bracket 9 with an adhesive or the like, the fixing point P may be a point on the main surface of the bottom member 5 on the contact area to which the adhesive is applied. Also, for example, a protrusion may be formed on the main surface of the bottom member 5, and the protrusion may be inserted into a recess formed in the vehicle (in the present embodiment, the interior part 10) to be fixed to the vehicle. In this case, the protrusion of the bottom member 5 may be regarded as the bracket 9 without providing a separate bracket 9. In this case, the surface of the protrusion of the bottom member 5 on the Z direction side may be the contact area, and a point on the contact area may be the fixed point P. Also, for example, a recess may be formed on the main surface of the bottom member 5, and the protrusion formed on the vehicle (in the present embodiment, the interior part 10) may be inserted into the recess of the main surface of the bottom member 5 to be fixed to the vehicle. In this case, the protrusion of the vehicle may be regarded as the bracket 9 without providing a separate bracket 9. In this case, the surface of the recess of the bottom member 5 on the Z direction side may be the contact area, and a point on the contact area may be the fixed point P. The position of the fixed point P will be described later.

[0032] In the example of Figure 4, fixed point P1 and fixed point P2 are arranged along the width direction of the vehicle. The same is true for fixed point P3 and fixed point P4. A line passing through fixed point P1 and fixed point P2 and a line passing through fixed point P3 and fixed point P4 are parallel to each other, and these four points form a rectangle.

[0033] 1 to 4, brackets 9 (brackets 91 to 94) serving as fixing members may be attached to the fixing points (fixing points P1 to P4). In this case, the housing bottom member 5 is fixed to the interior portion 10 via the brackets 9. The bracket 9 is a long plate-like member that is bent into a U-shape. The bracket 9 may also be bent into an S-shape. For example, the center of the bracket 9 in the plate width direction is positioned at the fixed points (fixed points P1 to P4). One side of the end of a convex surface 9a (the lower surface in FIG. 2) formed by bending the bracket 9 into a U-shape is in contact with the fixed point (fixed point P1 or P2). In the embodiment illustrated in FIGS. 1 to 4, the direction perpendicular to the convex surface 9a of the bracket 9 perpendicularly intersects with the width direction of the vehicle.

[0034] In the embodiment illustrated in Figures 1 to 4, the bracket 9 is composed of a convex surface 9a formed by bending in a U-shape, one surface 9b connected to the convex surface 9a, and the other surface 9c connected to the convex surface 9a. The one surface 9b and the other surface 9c are each formed approximately perpendicular to the convex surface 9a. In the embodiment illustrated in Figures 1 to 4, the bracket 9 has one surface 9b connected to the convex surface 9a in contact with the housing bottom member 5, and the other surface 9c connected to the convex surface 9a in contact with the interior part 10. The bracket 9 is fixed to the housing bottom member 5 and the interior portion 10 by fasteners such as screws (not shown).

[0035] FIG. 4 illustrates a midpoint Q between fixed point P1 and fixed point P2. The distance between the midpoint Q and the fixed point P1, or the distance between the midpoint Q and the fixed point P2 is defined as distance X. From the viewpoint of obtaining favorable vibration characteristics (JIS D 1601 vibration test method for automobile parts), the distance X is preferably 30 to 200 mm, and more preferably 50 to 130 mm.

[0036] The distance between fixed points P1 and P3, or the distance between fixed points P2 and P4, which are arranged in the vertical direction in FIG. For the same reasons as for the distance X, the distance Y is preferably from 30 to 200 mm, and more preferably from 35 to 125 mm.

[0037] In a preferred embodiment of the present invention, as the intermediate point Q, two fixed points are selected from the top, that is, from the Y direction side, among the fixed points set on the housing bottom member 5, and the midpoint between them is adopted. For example, FIGS. 1 to 4 show an example in which housing bottom member 5 is fixed to interior portion 10 at four fixing points (fixing points P1 to P4), two on each side of the top and bottom. As shown in Figures 1 to 4, when there are multiple fixed points above and below, the top two fixed points (fixed points P1 and P2 in Figures 1 to 4) are used as fixed points to define intermediate point Q (and thus the virtual plane R described later).

[0038] When there are three or more fixed points on a line at the same height, i.e., at the same position in the Y direction, two fixed points with the smallest distance between them are selected, and the midpoint between them is taken as the midpoint Q. When there are three or more fixed points at the same height and at equal intervals, the midpoint of any combination of two fixed points with the narrowest interval may be set as the midpoint Q. In other words, when there are multiple candidates for the midpoint Q (and thus the virtual surface R and virtual line L described below), it is sufficient that any one of them satisfies the requirements of the present invention.

[0039] The housing bottom member 5 may be fixed to the interior portion 10 at three points. For example, referring to Fig. 4, it is assumed that there is no fixed point P1 and fixed point P2, and instead, another fixed point P' (not shown in Fig. 4, etc.) exists on the line connecting fixed point P1 and fixed point P2. In this case, housing bottom member 5 is fixed to interior part 10 at three points, fixed point P3, fixed point P4, and fixed point P'. In this case, if there is no difference in height between fixed point P3 and fixed point P4, the point closer to fixed point P' is selected, and the midpoint between fixed point P' and the point is set as midpoint Q. If there is no difference in distance between fixed point P', an arbitrary one is selected, and the midpoint between fixed point P' and the point is set as midpoint Q.

[0040] The housing bottom member 5 may be fixed to the interior portion 10 at only one fixed point (for convenience, referred to as "fixed point P"). In other words, a bracket 9 may be disposed only at fixed point P", and the housing bottom member 5 may be fixed to the interior portion 10 using this bracket 9. In this case, an imaginary plane perpendicular to the side of the convex surface 9a of the bracket 9 arranged at the fixed point P'' that contacts the housing bottom member 5 is defined as an imaginary plane R, which will be described later.

[0041] The housing bottom member 5 may be fixed to the interior part 10 without using the bracket 9, for example, by deforming a part of the housing bottom member 5. Conversely, a part of the interior part 10 may be deformed and fixed to the housing bottom member 5. In this case, each fixing point may be defined as the center of each fixing location. As long as the above-mentioned fixing conditions are met, a portion of the housing side wall 8 may be deformed and fixed to the interior part 10, or conversely, a portion of the interior part 10 may be deformed and fixed to the housing side wall 8.

[0042] <Ratio Z / Z cg 〉 1 to 4 show a virtual plane R that passes through the midpoint Q and is perpendicular to the line connecting the fixed point P1 and the fixed point P2 (the two fixed points P used to define the midpoint Q). As described above, when the housing bottom member 5 is fixed to the interior part 10 using the bracket 9 at only one fixed point P'', the virtual plane R is a virtual plane perpendicular to the side of the convex surface 9a of the bracket 9 that contacts the housing bottom member 5, and can also be said to be a virtual plane that passes through the fixed point P'' and includes the thickness direction and vertical direction of the cover glass 2 at the fixed point P''. In other words, in an embodiment having the midpoint Q, the virtual plane R can be defined as a YZ plane including the midpoint Q. Also, when the housing bottom member 5 is fixed to the interior part 10 at only one fixed point P'', the virtual plane R can be defined as a YZ plane including the fixed point P''.

[0043] Here, please refer to FIG. 2. The length of the intersection line between the main surface of the cover glass 2 and the imaginary plane R is defined as a distance Z cgFurthermore, the length from the upper end (end on the Y direction side) of the intersection line between the main surface of the display panel 3 and the imaginary plane R to the point corresponding to the midpoint Q is defined as the distance Z. However, in the case where the housing bottom member 5 is fixed to the interior part 10 at only one fixed point P″, the above-mentioned “point corresponding to the midpoint Q” is read as “point corresponding to the fixed point P″”. In other words, the length from the upper end (end on the Y direction side) of the intersection line between the main surface of the display panel 3 and the imaginary plane R to the point corresponding to the fixed point P″ is defined as the distance Z. Regarding the distance Z, the direction from the center of the display panel 3 toward the outside of the display panel 3 is defined as the positive direction, and the direction from the outside of the display panel toward the center of the display panel 3 is defined as the negative direction. In addition, the "point corresponding to intermediate point Q" or the "point corresponding to fixed point P" refers to a point positioned on the main surface of the display panel 3 by moving intermediate point Q or fixed point P" in the thickness direction of the in-vehicle display device 1 (the vertical direction in Figure 1).

[0044] In this application, distance Z and distance Z cg Ratio to Z / Z cg When the distance Z exceeds 0.6, it is defined as a standing type. cg Ratio to Z / Z cg When the ratio is 0.6 or less, it is defined as an in-dash type or an on-dash type.

[0045] The in-vehicle display device 1 detects distance Z and distance Z cg Ratio to Z / Z cg is 0.6 or less, and is an in-dash type or an on-dash type (hereinafter simply referred to as "in-dash type").

[0046] <Formula (1)~Formula (4)> In the in-dash type vehicle-mounted display device 1, as described above, in order for the cover glass to exhibit good impact resistance, it may not be sufficient to merely satisfy "formula (I)" described in Patent Document 1. Furthermore, it is necessary to take into consideration the shape of the housing bottom member 5 that may have the rib 7.

[0047] 2 illustrates an imaginary line L that passes through the thickness direction of the in-vehicle display device 1 from the upper end to the lower end side of the intersection line between the main surface of the display panel 3 and the imaginary plane R. The imaginary line L is perpendicular to the surface (main surface) of the cover glass 2. The point on the main surface of the cover glass 2 through which the imaginary line L passes is defined as an impact point P. A head impact test, which will be described later, is a test in which an impactor is struck against this impact point P to evaluate the impact resistance of the cover glass 2. The present inventors have found that when a laminate of n layers from the cover glass to the bottom member of the housing on the imaginary line L satisfies the following formula (1), the cover glass has excellent impact resistance.

[0048]

number

[0049] In the above formula (1), E1: Young's modulus of the cover glass (unit: GPa) t1: thickness of cover glass (unit: mm) and S is expressed by the following formula (2). The S value calculated by the following formula (2) can be said to indicate the rigidity of the laminate consisting of each component (each layer) on the imaginary line L. The impact point P is a position in the in-vehicle display device 1 where impact resistance is likely to be weakened. When the rigidity of the laminate on the imaginary line L passing through the impact point P is within the above range, deformation of the cover glass 2 is suppressed and the stress generated by impact does not exceed the breaking stress of the glass, so that the impact resistance of the cover glass 2 is excellent.

[0050]

number

[0051] In the above formula (2), E2: Young's modulus of the second layer (unit: GPa) t2: thickness of the second layer (unit: mm) E n : Young's modulus (unit: GPa) of the nth layer (in this embodiment, the bottom member of the housing) t n: Thickness of the nth layer (in this embodiment, the bottom member of the housing) (unit: mm) where t1, t2 and t n The thickness t of any kth layer among layers 1 to n, including k is expressed by the following formula (3).

[0052]

number

[0053] In the above formula (3), a: Thickness (unit: mm) of the kth layer of plate-like member (when k=n, in this embodiment, the housing bottom plate of the housing bottom member) w2: the width (unit: mm) of the rib Rb1 that is closest to point p on the kth layer of plate-like member (when k=n, in this embodiment, the housing bottom plate of the housing bottom member) through which the virtual line L passes w1: Distance between rib Rb1 and rib Rb2 (unit: mm) h: the thickness of the rib Rb1 and the rib Rb2 (unit: mm). As described above, in this embodiment, the case where the member consisting of the plate-like member and the rib is limited to the housing bottom member is exemplified. Therefore, for example, when k=n, that is, the plate-like member and the rib in the housing bottom member are described, as exemplified in Figs. 5 to 9, the rib Rb1 is the rib 7 of the bottom member 5 that is closest to the point p on the main surface 6B (the main surface on the side where the rib 7 is provided) of the housing bottom plate 6 through which the virtual line L passes, among the ribs 7. The rib Rb2 is the rib 7 that is located on the line that connects the rib Rb1 and the point p on the housing bottom plate 6 through which the virtual line L passes, and is closest to the rib Rb1. In other words, the rib Rb2 is a rib that is located in the direction of the line that passes through the rib Rb1 and the point p on the housing bottom plate 6 through which the virtual line L passes, and is perpendicular to the center line of the rib Rb1. Moreover, the width of the rib Rb1 refers to the width of the rib Rb1 when viewed from the extension direction of the rib Rb1. Moreover, the distance between the rib Rb1 and the rib Rb2 refers to the distance between the central axis of the rib Rb1 and the central axis of the rib Rb2 when viewed from the extension direction of the rib Rb1. More specifically, the distance between the rib Rb1 and the rib Rb2 can be said to be the distance (the distance between the center lines) between the rib Rb1 (rib 72) and the rib Rb2 (rib 73) on the perpendicular line of the rib Rb1 (rib 72) that passes through the point p. Moreover, when the thicknesses of the rib Rb1 and the rib Rb2 in the Z direction are different, h may be the average value of the thicknesses of the rib Rb1 and the rib Rb2 in the Z direction.

[0054] In formula (3), b is expressed by the following formula (4).

[0055]

number

[0056] Since there may be cases where the members of each layer, including the bottom member of the housing, do not have ribs, h is a number including 0, that is, a number equal to or greater than 0.

[0057] If the kth layer member does not have a rib, h = 0, so its thickness t k From the above equations (3) and (4), k =a is calculated. In other words, in this embodiment, the first layer (only the cover glass, which is a plate-shaped member) and the second layer (only the display panel, which is a plate-shaped member) do not have ribs, so their thickness is the thickness of the cover glass or display panel itself, which is a plate-shaped member. Conversely, for example, if the first and second layers also have ribs, their respective thicknesses t1 and t2 are calculated based on the above formulas (3) and (4).

[0058] FIG. 5 is a cross-sectional view showing the housing bottom member 5 and is also an enlarged view of FIG. FIG. 6 is a plan view that typically shows the rib 7 (rib 72 and rib 73) in FIG. 5, and is also a view of the housing bottom plate 6 (not shown in FIG. 6) as seen from the rib 7 side. 5 and 6 show the above-mentioned points a, h, w1, w2 and p (a and h are shown only in FIG. 5). Point p is a point on the housing bottom plate 6 that corresponds to the impact point P of the cover glass 2, and both are located on the imaginary line L. In addition, b is the distance from the surface (surface on the side of the cover glass 2) of the housing bottom plate 6 to the centroid G (the centroid in FIG. 5, which is a cross-sectional view of the housing bottom member 5) in FIG.

[0059] 5 and 6, since both the rib 72 and the rib 73 are equidistant from the point p, the rib Rb1 may be either the rib 72 or the rib 73. However, for the sake of convenience, the rib 72 is referred to as the rib Rb1 in FIGS. 5 and 6. 5 and 6, it can be seen that w2 is the width of the rib Rb1 closest to the point p. It can also be seen that w1 is the distance between the rib Rb1 and the rib Rb2 (the distance between the center lines of the rib Rb1 and the rib Rb2).

[0060] In formulas (3) and (4), the thickness (t n )(thickness of the kth layer t k ) is required.

[0061] FIG. 7 is a schematic diagram showing the rib 7 (the rib 72 and the rib 73) when the position of the point p is different from that in FIG. In Fig. 7, point p (corresponding to impact point P) is located outside (to the left) of rib 72, not between rib 72 and rib 73. In Fig. 7, the rib 72 closest to point p is rib Rb1, and the rib 73 located on the line connecting point p and rib Rb1 is rib Rb2. Then, the width w2 of the rib Rb1 and the distance w1 between the ribs Rb1 and Rb2 are calculated. Furthermore, the distance w3 between the point p and the rib Rb1 (the distance from the point p to the center line of the rib Rb1) is also calculated. If the distance w1 is equal to or greater than the distance w3 (w1 ≧ w3), use the values ​​of w1 and w2 to calculate equations (3) and (4) to obtain t n (tk ) value. However, when the distance w3 is greater than the distance w1 (w3>w1), the values ​​of w1 and w2 are not applied to the formulas (3) and (4), and the calculation is performed as if the rib 7 does not exist.

[0062] FIG. 8 is a schematic diagram showing the ribs 7 in the horizontal direction (ribs 75 and ribs 76) in addition to the ribs 7 in the vertical direction (ribs 72 and ribs 73). 8, the rib Rb1 closest to point p is the horizontal rib 75. The rib Rb2 located on the line connecting point p and the rib Rb1 is the rib 76 parallel to the rib 75. In this way, even if there are a plurality of ribs 7 (see, for example, FIG. 3), it is necessary to consider only the rib Rb1 (and the rib Rb2 corresponding to it) that is closest to the point p.

[0063] When there are a plurality of ribs Rb1 that are equidistant to the point p, the relationship between the distance w1 and the distance w3 described above is considered for all of them. Then, for any one of the ribs Rb1, if the distance w1 is equal to or greater than the distance w3 (w1 ≧ w3), the values ​​of w1 and w2 for that rib Rb1 are used to calculate equations (3) and (4), and t n (t k ) value.

[0064] Fig. 9 is a schematic diagram showing a state in which the aligned ribs 7 are not parallel to each other. That is, in Fig. 9, the vertical ribs 72 and 73 are not parallel to each other, and the horizontal ribs 75 and 76 are also not parallel to each other. 9, the rib Rb1 closest to the point p is the rib 73. The rib Rb2 located on the line connecting the point p and the rib Rb1 (rib 73) is not the rib 72 but the rib 75. Then, the width w2 of the rib Rb1 (rib 73) and the distance w1 (the distance between the center lines) between the rib Rb1 (rib 73) and the rib Rb2 (rib 75) on the perpendicular line to the rib Rb1 (rib 73) passing through the point p are obtained.

[0065] In this way, the shape formed by the intersection of a plurality of ribs 7 does not have to be a quadrangle (rectangle) with four right-angled corners, and may be a quadrangle other than a rectangle or another polygon. Even in this case, if the above definitions are used, the values ​​of w1 and w2 required for the calculation of equations (3) and (4) can be determined.

[0066] The cross-sectional shape of the rib 7 is, for example, rectangular or trapezoidal. Fig. 13 is a schematic diagram showing a rib 7 when the cross-sectional shape is a trapezoid. The above-mentioned w2 and w3 are values ​​at a position of height h / 2 from the surface (the surface on which the rib 7 is provided) of the housing bottom plate 6 of the housing bottom member 5, as shown in Fig. 13.

[0067] It is demonstrated in the Examples described below that when the above formula (1) is satisfied, the cover glass has excellent impact resistance. That is, in the [Examples], it is shown that when the above formula (1) is not satisfied (comparative example), the stress generated in the cover glass is greater than the threshold for cracking, whereas when the above formula (1) is satisfied (Examples), the stress generated in the cover glass is less than the threshold for cracking. Furthermore, when the following formula (4A) is satisfied, the stress generated in the cover glass is further reduced, and the frequency of cracking can be further reduced, which is more preferable.

[0068]

number

[0069] As described above, the in-dash type vehicle-mounted display device is likely to have poor shock absorption. Specifically, the in-dash type vehicle-mounted display device may experience a deceleration of the impactor of 50 G or more in a head impact test.

[0070] The head impact test is a test in which an impactor is struck at an impact point P (see Figure 2) on the main surface of the cover glass 2 through which the imaginary line L passes, so that the impact energy is 152 J (see [Example] described below).

[0071] From the standpoint of passenger safety, it is required that the time during which the deceleration of the impactor exceeds 80G in the head impact test (hereinafter, for convenience, also referred to as "time during which deceleration exceeds 80G") be less than 3 milliseconds (ms). From this viewpoint, it is preferable that the first to n-th layers on the virtual line L of the in-vehicle display device further satisfy the following formula (5). S≦-588.8t1+2660…(5) It is demonstrated in the Examples described below that when the above formula (5) is satisfied, the time during which the deceleration exceeds 80 G is less than 3 milliseconds.

[0072] As described above, in practice, at least one layer of the members from the cover glass (first layer) to the housing bottom member (nth layer) may be an adhesive layer. For example, in the above-mentioned four-layer structure, an adhesive layer may be disposed between the cover glass (first layer) and the display panel (second layer). Here, Young's modulus of the adhesive layer (E 粘着層 ) and thickness (t 粘着層 ), the formula (2) for calculating the S value is expressed as follows: S=E 粘着層 ·t 粘着層 2 +E2·t2 2 +E3·t3 2 +E4·t4 2 … (2) However, the Young's modulus of the adhesive layer (E 粘着層 ) is very small compared with the Young's modulus of the other layers. Moreover, the thickness of the adhesive layer (t 粘着層 ) is, for example, 5 to 400 μm. For this reason, "E 粘着層 ·t 粘着層 2 The other values ​​of "E2·t2 2 " ~ "E4·t42 " is negligibly small compared to the value of Therefore, even if an adhesive layer exists from the first layer to the nth layer, when considering the formula (2), the adhesive layer may be regarded as not existing. 粘着層 t 粘着層 2 " may be considered to have a value of 0 (zero).

[0073] For the same reason, other thin film layers and resin layers included from the cover glass (first layer) to the housing bottom member (nth layer) may be considered not to exist when considering formula (2). For example, thin film layers such as an AR (Anti-Reflection) layer and an AFP (Anti-Finger-Print) layer are formed on the surface of the cover glass. In addition, the display panel has thin film layers such as TFTs and transparent conductors. However, these thin film layers are extremely thin compared to, for example, the cover glass itself and the glass substrate (soda-lime glass, etc.) that constitutes the display panel. Furthermore, the backlight unit or the like may have a resin layer, but the Young's modulus of the resin layer is very small. Therefore, if these thin film layers and resin layers are assumed to be the "mth layer", then "E m t m 2 " may be considered to have a value of 0 (zero).

[0074] An example of the configuration of an in-vehicle display device having a thin film layer includes, for example, a configuration consisting of a cover glass, an OCA, a polarizing plate, a color filter, a liquid crystal, a TFT substrate, a polarizing plate, a brightness enhancement film, a lens sheet, a diffusion plate, a light guide plate, a reflective film, a backlight unit case, a printed wiring board, a housing bottom member, and a housing resin cover.

[0075] The members constituting each layer will be specifically described below. The materials of each member are not particularly limited as long as the distance from the cover glass to the housing bottom member on the imaginary line L of the in-vehicle display device satisfies the above-mentioned formula (1). Furthermore, each member may be a composite material made of a combination of multiple materials.

[0076] <Cover glass> The cover glass is preferably a strengthened glass, such as a chemically strengthened glass. The thickness (DOL) of the compressive stress layer in the tempered glass is, for example, 10 μm or more, preferably 15 μm or more, more preferably 25 μm or more, and even more preferably 30 μm or more. The thickness (DOL) of the compressive stress layer is, for example, 180 μm or less, and preferably 50 μm or less. The surface compressive stress (CS) of the compressive stress layer is preferably 500 MPa or more, more preferably 650 MPa or more, and even more preferably 750 MPa or more. The upper limit of the surface compressive stress (CS) is not particularly limited, but for example, CS is preferably 1200 MPa or less. A typical method for obtaining chemically strengthened glass by chemically strengthening glass is to immerse the glass in KNO3 molten salt, perform ion exchange treatment, and then cool it to about room temperature. The treatment conditions such as the temperature of the KNO3 molten salt and the immersion time may be set so that the surface compressive stress and the thickness of the compressive stress layer are the desired values. Examples of glass types include soda lime glass, aluminosilicate glass (SiO2-Al2O3-Na2O-based glass), etc. Among these, aluminosilicate glass is preferable from the viewpoint of strength. An example of the glass material is a glass material containing, in mole percent based on oxides, 50-80% SiO2, 1-20% Al2O3, 6-20% Na2O, 0-11% K2O, 0-15% MgO, 0-6% CaO, and 0-5% ZrO2. Chemically strengthened glass based on aluminosilicate glass (for example, "Dragontrail (registered trademark)" manufactured by AGC) is also preferably used.

[0077] The Young's modulus (E1) of the cover glass is preferably 60 GPa or more, and more preferably 70 GPa or more. On the other hand, the Young's modulus (E1) of the cover glass is preferably 90 GPa or less, more preferably 80 GPa or less, and even more preferably 75 GPa or less. The Young's modulus of each member including the cover glass is determined by a tensile test (JIS K7161 / JIS K7113) (hereinafter the same applies).

[0078] The thickness (t1) of the cover glass is preferably 0.5 mm or more, more preferably 0.7 mm or more, and even more preferably 1.1 mm or more. On the other hand, the thickness (t1) of the cover glass is preferably 2.5 mm or less, more preferably 2.0 mm or less, and even more preferably 1.3 mm or less. The thickness of each member including the cover glass is the length in the vertical direction or the length in the Z direction in FIG. 1 (the same applies below).

[0079] The cover glass has, for example, a rectangular shape when viewed from the direction of the main surface. When the cover glass is rectangular, for example, the size of the cover glass is such that the length in the longitudinal direction is 100 to 800 mm and the length in the lateral direction is 40 to 300 mm.

[0080] Here, the mass of the in-vehicle display device per unit area of ​​the cover glass is M (unit: g / cm 2 ), it is preferable that the mass M and the thickness t1 of the cover glass satisfy the following formulas (6) and (7). In addition, when a fixing member such as a bracket is used to fix the housing bottom member of the in-vehicle display device to the interior portion of the vehicle, the mass M includes the mass of the fixing member. M≧-0.10t1 4 +0.38t1 3 -0.62t1 2 +0.42t1+1.75…(6) M≦0.03t1+2.40…(7)

[0081] When the mass M satisfies the formula (6), it is possible to obtain an in-vehicle display device in which deformation of the cover glass due to a collision is suppressed and the cover glass is less likely to break. When the mass M satisfies the formula (7), the deceleration during a collision is unlikely to become high, and the time during which the deceleration is high can be shortened, thereby making it possible to obtain an in-vehicle display device that is unlikely to cause damage to a person or other object hit by the collision.

[0082] In addition, in formula (6), as the value of t1 becomes 0.7 or more, the value of the mass M decreases. Therefore, from the viewpoint of reducing the weight of the in-vehicle display device, the thickness (t1) of the cover glass is preferably 0.7 mm or more.

[0083] <Display panel> The display panel may be, for example, a liquid crystal panel, an organic EL panel, a PDP, an electronic ink panel, or the like, and may have a touch panel, etc. In a display panel, the glass substrate is generally the thickest and governs the rigidity of the entire display panel. Therefore, the Young's modulus of the glass substrate may be regarded as the Young's modulus of the display panel. The Young's modulus (E2) of the display panel is preferably 60 GPa or more, and more preferably 70 GPa or more. On the other hand, the Young's modulus (E2) of the display panel is preferably 90 GPa or less, and more preferably 75 GPa or less. The thickness (t2) of the display panel is preferably 1.0 mm or more, and more preferably 1.1 mm or more. On the other hand, the thickness (t2) of the display panel is preferably 2.0 mm or less, and more preferably 1.3 mm or less.

[0084] FIG. 10 is a schematic diagram showing a state in which the display panel 3 is attached to the cover glass 2. As shown in FIG. In FIG. 10, from the viewpoint of adhering and holding the cover glass 2 with sufficient adhesive strength, the distance D1 is preferably from 2 to 30 mm, and more preferably from 5 to 20 mm. From the viewpoint of the adhesive strength and design, the distance D2 is preferably from 2 to 200 mm, and more preferably from 5 to 150 mm.

[0085] <Backlight unit> A backlight unit is generally composed of components such as a lens sheet, a diffusion sheet, a light guide plate, a lamp, and a reflector. Among these components, the light guide plate is usually the thickest, and it governs the rigidity of the entire backlight unit. For this reason, the Young's modulus of the light guide plate is regarded as the Young's modulus of the backlight unit. The Young's modulus (E3) of the backlight unit is preferably 1 GPa or more, more preferably 2 GPa or more, and even more preferably 60 GPa or more. On the other hand, the Young's modulus (E3) of the backlight unit is preferably 90 GPa or less, and more preferably 85 GPa or less. The thickness (t3) of the backlight unit is preferably 1 mm or more, more preferably 2 mm or more, and further preferably 3 mm or more. On the other hand, the thickness (t3) of the backlight unit is preferably 10 mm or less, more preferably 6 mm or less, and further preferably 5 mm or less.

[0086] FIG. 11 is an enlarged cross-sectional view showing the in-vehicle display device 1. As shown in FIG. 11, a housing side wall 8 may be disposed at a position opposite to an end face of the display panel 3 with a gap therebetween. Here, the housing side wall 8 may be a part of the backlight unit 4. The gap distance d1 between the end face of the display panel 3 and the side wall 8 of the housing (the distance d1 between the end face of the display panel 3 and the side wall 8 of the housing) is preferably 2 mm or less, and more preferably 1.8 mm or less. This reduces the stress applied to the cover glass 2 during a head impact test, resulting in better impact resistance.

[0087] 11, a gap is provided between an end of the display panel 3 (a portion within 5 mm from the end face) and a member (here, a part of the backlight unit 4) closer to the housing bottom member 5 than the display panel 3. The distance d2 of this gap (the distance d2 between the end of the display panel and the member closer to the housing bottom member than the display panel) is preferably 1 mm or less, and more preferably 0.5 mm or less.

[0088] <Housing bottom part> The Young's modulus of the housing bottom member is, for example, preferably 1.5 GPa or more, more preferably 40 GPa or more, and even more preferably 60 GPa or more, while the Young's modulus of the housing bottom member is preferably 250 GPa or less, more preferably 230 GPa or less, even more preferably 100 GPa or less, and particularly preferably 80 GPa or less. When the housing bottom member has ribs, the Young's modulus (E4) of the housing bottom member is preferably 1.5 GPa or more and 100 GPa or less, and more preferably 40 GPa or more and 80 GPa or less. When the housing bottom member does not have a rib, the Young's modulus (E4) of the housing bottom member is preferably 40 GPa or more and 250 GPa or less, and more preferably 60 GPa or more and 230 GPa or less.

[0089] The material of the housing bottom member is preferably a metal (simple substance) or an alloy containing a metal element such as aluminum or magnesium, etc. The material of the housing bottom member may be a resin or a laminate of a resin layer and a metal layer. Please refer to FIG. 5 for the shape of the bottom member of the housing. From the viewpoint of productivity, the thickness a in FIG. 5, that is, the thickness of the housing bottom plate 6, is preferably 0.5 mm or more, and more preferably 1 mm or more. On the other hand, in terms of weight reduction, a in FIG. 5 is preferably 6 mm or less, and more preferably 5 mm or less.

[0090] 5, ie, the thickness of the rib 7 may be 0 mm, but from the viewpoint of obtaining the effect of increasing rigidity by the rib 7, it is preferably 1 mm or more, and more preferably 2 mm or more. On the other hand, h in FIG. 5 is preferably 20 mm or less, and more preferably 10 mm or less, from the viewpoint of ease of production of the housing bottom member 5 and from the viewpoint of preventing the size of the housing bottom member 5 from becoming too large.

[0091] From the viewpoint of ease of production of the housing bottom member 5, w1 in FIG. 5 is preferably equal to or greater than 1 mm, and more preferably equal to or greater than 2 mm. On the other hand, w1 in FIG. 5 is preferably 40 mm or less, and more preferably 30 mm or less, from the viewpoint of effectively suppressing the generation of stress in the cover glass 2 during a head impact test.

[0092] From the viewpoint of ease of production of the housing bottom member 5 and from the viewpoint of obtaining the effect of increasing the rigidity by the rib 7, w2 in FIG. 5 is preferably 1 mm or more, and more preferably 3 mm or more. On the other hand, from the viewpoint of obtaining a weight reduction effect of the in-vehicle display device 1, w2 in FIG. 5 is preferably 20 mm or less, and more preferably 15 mm or less.

[0093] <Modification> 1 to 9 (particularly, Fig. 1, Fig. 2 and Fig. 10) show an in-vehicle display device having one display panel, but the present invention is not limited to this, and there may be multiple display panels as shown in Fig. 12. When there are multiple display panels, values ​​based on the above-mentioned formulas (1) to (4) may be calculated for each display panel.

[0094] Fig. 12 is a schematic diagram showing a modified example of an in-vehicle display device, and shows only a cover glass 2, a display panel 3, and a bracket 9. In Fig. 12, two display panels 3 are attached to one cover glass 2, and a housing bottom member 5 (not shown in Fig. 12) is fixed to an interior part 10 (not shown in Fig. 12) using a bracket 9. In FIG. 12, two fixed points P1 and P2 are set. Therefore, the above-mentioned virtual surface R and the ratio Z / Z cg After determining the virtual line L and the like, values ​​can be calculated based on the above-mentioned formulas (1) to (4).

[0095] 12, a bracket 9 is disposed on the outer side of the display panel 3. As shown in FIG. 12, when there are not two fixing points on the surface of the housing bottom member 5 facing the display panel 3, fixing points adjacent to the outer periphery of the display panel 3 are considered. For example, for the display panel 3 (display panel 3a) on the left side in Fig. 12, four points (fixed points P1 to P4) existing outside the panel are set as fixed points. Of these, the midpoint between fixed points P1 and P2, which are the two fixed points from the top, is set as intermediate point Q. Then, a plane that passes through intermediate point Q and is perpendicular to the line connecting fixed points P1 and P2 is set as imaginary plane R. 12, the three points (fixed point P1, fixed point P4, and fixed point P5) existing outside the right-side display panel 3 (display panel 3b) are set as fixed points. Among these, the midpoint between fixed point P2 and fixed point P5 is set as intermediate point Q.

[0096] When the fixed point is located outside the display panel 3, the intermediate point Q may also be located outside the display panel 3 depending on the positional relationship. In this case, the distance Z (the length from the top end to the point corresponding to the midpoint Q on the intersection line between the main surface of the display panel 3 and the imaginary surface R) is a negative value, and the ratio Z / Z cg Since is less than 0.6, it can be determined to be an in-dash type.

[0097] The shapes of the cover glass 2 and the display panel 3 are not limited to a rectangle (see Figs. 1, 2, and 10), and may be a quadrangle other than a rectangle or another polygon as shown in Fig. 12. Alternatively, they may be a circle or the like. Furthermore, the cover glass 2 and the display panel 3 are not limited to being flat plate-like members, and may be curved plate-like members. EXAMPLES

[0098] Hereinafter, the present invention will be described in detail with reference to examples, but the present invention is not limited to the following examples. Examples 1 to 18 and 26 to 28 are working examples, and Examples 19 to 25 are comparative examples.

[0099] In the examples and comparative examples, a simulation model of a display device 1 based on Figs. 1 to 11 was prepared, and a simulation was performed in which an impact was applied to the simulation model to simulate a head impact test. As shown in Fig. 1, the model of the display device 1 had a cover glass 2 (first layer), a display panel 3 (second layer), a backlight unit 4 (third layer), and a housing bottom member 5 (fourth layer). The cover glass model was a rectangular chemically strengthened glass model made by chemically strengthening aluminosilicate glass-based chemically strengthened glass ("Dragon Trail" manufactured by AGC Inc.) that had been subjected to a chemical strengthening treatment, with a DOL of 35 μm and a CS of 750 MPa. The size of the cover glass was 250 mm in the longitudinal direction and 150 mm in the lateral direction. The Young's modulus (E1) and thickness (t1) of the cover glass will be described later.

[0100] The display panel model was a simulation of a structure in which polarizing plates (material: triacetyl cellulose) were attached to both sides of soda lime glass, and the thickness was set to 1.1 mm. The adhesive layer model was configured to mimic OCA ("MHM-FWD" manufactured by Nichiei Kako Co., Ltd.). The model of the backlight unit was configured to simulate a plate-like body (material: polycarbonate) with a thickness of 3 mm. The models of the bottom member and side walls of the housing were modeled after aluminum material. We assumed that each part was attached using double-sided tape (3M's "VHX1701-04", thickness: 0.4 mm). The bottom material of the case was provided with a lattice-like rib (see Figure 3).

[0101] In this simulation, the housing was fixed to the interior of the vehicle using a bracket. The bracket model was assumed to have a thickness of 2 mm, plate width of 20 mm, length of 50 mm, and a Young's modulus of 206 GPa to simulate SS400 steel, with a component bent at a right angle with a length ratio of 2:5:2. In the head impact test described below, it was assumed that a 50 mm thick sponge ("Memory Foam CF-45M" manufactured by Aearo Technologies LLC) was placed between the bottom member of the housing and the interior part.

[0102] The ratio Z / Z mentioned above cg The values ​​of t1, a, w1, w2, h and X were adjusted to be different for each test specimen of the in-vehicle display device produced. The values ​​are shown in Table 1 below. Note that a, w1, w2 and h here are values ​​used to calculate t4, that is, a, w1, w2 and h related to the bottom member of the housing. Furthermore, Table 1 below also lists the value of the above-mentioned mass M (the mass of the in-vehicle display device per unit area of ​​the cover glass). Other values ​​for each test specimen were as follows: E1: 74GPa (Young's modulus of cover glass) E2: 73GPa (Young's modulus of soda-lime glass) E3: 2.2GPa (Young's modulus of polycarbonate) E4: 70GPa (Young's modulus of aluminum) t2:1.1mm t3:3mm D1: 12mm D2: 40mm d1::1.5mm d2: 0.5mm

[0103] In all the examples, the mass M of the in-vehicle display device per unit area of ​​the cover glass satisfied the above-mentioned formulas (6) and (7).

[0104] <Head Impact Test (HIT)> A simulation was performed in which an impactor collided with the impact point P of the model generated for each example under the following conditions. A hemispherical rigid impactor (material: aluminum, diameter: 165 mm, mass: 6.8 kg) was collided with the cover glass at impact point P (see Figure 2). The direction in which the impactor collided with the cover glass was set at an angle of 90° to the main surface of the cover glass. The maximum impact speed was set to 24.1 km / h, and the energy at the time of impact was set to 152 J. The deceleration of the impactor (unit: G) was then calculated.

[0105] (Evaluation Results) The analysis results of the stress generated in the cover member 2 when the impactor collides with the impact point P were obtained by simulation. If the maximum stress generated in the cover member 2 was equal to or less than a predetermined threshold and was 12% or more smaller than the threshold, the judgment was A; if it was 0% or more but less than 12% smaller than the threshold, the judgment was B; if it was greater than the threshold and was more than 0% but less than 12% larger than the threshold, the judgment was C; and if it was 12% or more larger than the threshold, the judgment was D. When test specimens of the same configuration are used, due to variations in the strength of the cover material (cover glass) 2, even with the same generated stress, some will crack and some will not; the closer the generated stress is to the threshold for cracking, the higher the frequency of cracking. In the cases of A and B, the maximum stress generated is below the threshold value, making it difficult for the cover glass to crack due to the head impact test. In the cases of C and D, the maximum stress generated is greater than the threshold value, making it easier for the cover glass to crack due to the head impact test. Furthermore, in the case of A, the frequency of cracking can be significantly reduced. In addition, the analysis results of the deceleration of the impactor were also obtained in the simulation, as shown in Table 1.

[0106] [Table 1]

[0107] Furthermore, among Examples 1 to 18 and 26 to 28, Examples 26 to 28, which do not satisfy formula (5), had a time period during which the deceleration exceeded 80G of 3 ms or more, whereas Examples 1 to 18, which satisfy formula (5), had a time period during which the deceleration exceeded 80G of 3 ms or less. All of Examples 1 to 18 and 26 to 28 satisfied formula (6). Comparing Examples 1 to 18 and 26 to 28, it was found that Examples 1 to 18, which satisfy Equation (7), tended to have smaller impactor deceleration values ​​and shorter times when the deceleration exceeded 80 G than Examples 26 to 28, which do not satisfy Equation (7).

[0108] Although the present invention has been described in detail and with reference to specific embodiments, it is apparent to those skilled in the art that various changes and modifications can be made without departing from the spirit and scope of the present invention. This application is based on a Japanese patent application (Patent Application No. 2021-066497) filed on April 9, 2021, the contents of which are incorporated herein by reference. [Explanation of symbols]

[0109] 1: In-vehicle display device 2: Cover glass 3: Display panel 4: Backlight unit 5: Bottom part of the housing 6: Bottom plate of the housing 7: Rib 8: Side wall of the housing 9 (91, 92, 93, 94): Bracket 10: Interior

Claims

1. An in-dash or on-dash type vehicle-mounted display device having n layers from a cover glass to a housing bottom member and having at least a display panel therebetween, Each layer of the member is made of only a plate-like member or the plate-like member and a rib. The housing bottom member is fixed to an interior portion of a vehicle at at least two fixing points, When a virtual plane R is a virtual plane that passes through the midpoint between the two fixed points and is perpendicular to the line connecting the two fixed points, On a virtual line L that passes through a line 5 mm below an upper end of an intersection line between the main surface of the display panel and the virtual plane R in a thickness direction of the in-vehicle display device, a distance from the cover glass to the housing bottom member satisfies the following formula (1), The in-vehicle display device, wherein the material of the housing bottom member is a metal, an alloy, a resin, or a laminate of a resin layer and a metal layer. [0010] In the formula (1), E １ : Young's modulus of the cover glass t １ : the thickness of the cover glass and S is expressed by the following formula (2). [0025] In the formula (2), E ２ : Young's modulus of the second layer t ２ : thickness of second layer E ｎ : Young's modulus of the nth layer t ｎ : thickness of nth layer and said t １ , the above t ２ and the t ｎ The thickness t of any kth layer among the 1st to nth layers ｋ is expressed by the following formula (3). [0030] In the formula (3), a: thickness of the plate-like member of the kth layer W ２ : The width of the rib Rb1 that is closest to the point p on the plate-like member of the kth layer through which the virtual line L passes W １ : The distance between the rib Rb1 and the rib Rb2 located in the direction of a line extending perpendicular to the center line of the rib Rb1 and passing through point p on the plate-like member through which the virtual line L passes h: thickness of the rib Rb1 and the rib Rb2 and b is expressed by the following formula (4). [0045] However, the values ​​of a, w 1 , w 2 and h in the formula (4) are the same as the values ​​of a, w 1 , w 2 and h in the formula (3), respectively.

2. An in-dash or on-dash type vehicle-mounted display device having n layers from a cover glass to a housing bottom member and having at least a display panel therebetween, Each layer of the member is made of only a plate-like member or the plate-like member and a rib. The housing bottom member is fixed to an interior portion of a vehicle at one fixing point, When a virtual plane R passes through the fixed point and includes the thickness direction and the vertical direction of the cover glass at the fixed point, On a virtual line L that passes through a line 5 mm below an upper end of an intersection line between the main surface of the display panel and the virtual plane R in a thickness direction of the in-vehicle display device, a distance from the cover glass to the housing bottom member satisfies the following formula (1), The in-vehicle display device, wherein the material of the housing bottom member is a metal, an alloy, a resin, or a laminate of a resin layer and a metal layer. [0050] In the formula (1), E １ : Young's modulus of the cover glass t １ : the thickness of the cover glass and S is expressed by the following formula (2). [006] In the formula (2), E ２ : Young's modulus of the second layer t ２ : thickness of second layer E ｎ : Young's modulus of the nth layer t ｎ : thickness of nth layer and said t １ , the above t ２ and the t ｎ The thickness t of any kth layer among the 1st to nth layers ｋ is expressed by the following formula (3). [0070] In the formula (3), a: thickness of the plate-like member of the kth layer W ２ : The width of the rib Rb1 that is closest to the point p on the plate-like member of the kth layer through which the virtual line L passes W １ : The distance between the rib Rb1 and the rib Rb2 located in the direction of a line extending perpendicular to the center line of the rib Rb1 and passing through point p on the plate-like member through which the virtual line L passes h: thickness of the rib Rb1 and the rib Rb2 and b is expressed by the following formula (4). [0080] However, the values ​​of a, w 1 , w 2 and h in the formula (4) are the same as the values ​​of a, w 1 , w 2 and h in the formula (3), respectively.

3. The in-vehicle display device according to claim 1 , wherein the housing bottom member is fixed to the interior portion by using a bracket.

4. The in-vehicle display device according to claim 1 , wherein a distance from the cover glass to the housing bottom member on the virtual line L further satisfies the following formula (5): S≦-588.8t １ +2660…(5)

5. The cover glass is a reinforced glass having a compressive stress layer having a thickness of 10 μm or more, The cover glass has a thickness of 0.5 to 2.5 mm; The Young's modulus of the cover glass is 60 to 90 GPa; The Young's modulus of the display panel is 60 to 90 GPa; 3. The in-vehicle display device according to claim 1, wherein the housing bottom member has a Young's modulus of 40 to 250 GPa.

6. 3. The in-vehicle display device according to claim 1, wherein in a head impact test in which an impactor is collided with an impact point P on the main surface of the cover glass through which the virtual line L passes, so that the impact energy is 152 J, the deceleration of the impactor is 50 G or more.

7. An in-vehicle display device as described in claim 1 or 2, wherein in a head impact test in which an impactor is collided with an impact point P on the main surface of the cover glass through which the virtual line L passes so that the impact energy is 152 J, the time during which the deceleration of the impactor exceeds 80 G is less than 3 milliseconds.

8. The in-vehicle display device according to claim 1 or 2, wherein, when a mass of the in-vehicle display device per unit area of ​​the cover glass is M, the following formulas (6) and (7) are satisfied: M≧-0.10t １ ４ +0.38t １ ３ -0.62t １ ２ +0.42t １ +1.75…(6) M≦0.03t １ +2.40…(7) However, the unit of the mass M is g / cm ２ It is.

9. a housing side wall is provided at a position opposite to an end surface of the display panel; The in-vehicle display device according to claim 1 , wherein a distance d1 between an end face of the display panel and a side wall of the housing is 2 mm or less.

10. The in-vehicle display device according to claim 1 , wherein a distance d2 between an end of the display panel and a member closer to the housing bottom member than the display panel is 1 mm or less.

11. The in-vehicle display device according to claim 1 , wherein a distance from the cover glass to the housing bottom member on the virtual line L satisfies the following formula (4A): [0097]

12. An in-vehicle display device as described in claim 1 or 2, wherein the housing bottom member is fixed to the dashboard of the vehicle.

13. The cover glass is A chemically strengthened glass having a thickness of 0.5 mm or more and 2.5 mm or less, The thickness of the compressive stress layer is 10 μm or more and 180 μm or less, The in-vehicle display device according to claim 1 or 2, wherein the surface compressive stress is 500 MPa or more and 1200 MPa or less.

14. An in-vehicle display device as described in claim 1 or 2, wherein the cover glass is a curved plate-shaped member.

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