Method of assembling a display device

Abstract

Method for assembling a display device Method for assembling a display device (10), characterized in that the method comprises the following successive steps: - assembling a screen (16) comprising a display face with a seal (18) thus forming a central assembly (72); - fixing a frame (12) with a lens (14) thus forming a front assembly (74); - assembling the central assembly (72) with the front assembly (74), the seal (18) maintaining a sealed connection between the lens (14) and the screen (16) and forming a spacer maintaining a space (37) between the screen (16) and the lens (14), the seal comprising at least one injection opening (44) comprising an internal orifice (46) opening into the space (37) and an external orifice (48) adapted to receive a tip (50) of an injector of a transparent glue (78); and - injecting said transparent glue (78) into the space (37) through the injection opening (44).Figure for abstract: 2.

Description

Title of the invention: Method of assembling a display device

[0001] The present invention relates to a method for assembling a display device.

[0002] In a display device, for example intended for the passenger compartment of a vehicle, it is known to fix the screen, or the panel, to a frame carrying a lens, forming the display surface of the display device, and to ensure the fixing of the screen to the lens and the transmission of light by an optical glue. The optical glue is for example activated and / or polymerized by heat, by ultraviolet radiation or after a certain period of time. During this polymerization operation, the screen must be immobile relative to the lens and therefore relative to the frame in all directions. The screen must therefore be firmly fixed to the frame. Such a firm and reversible fixing is for example obtained by screwing the screen onto the frame.However, such fixation also applies significant stresses to the screen, which can lead to defects in the display of images. Thus, such stresses are for example likely to generate a Mura effect on the display surface, thus degrading the quality of the displayed images.

[0003] To avoid these undesirable effects, a flexible attachment has been proposed, in which adhesive elements ensure the adhesion of the screen to the frame. However, the assembly is then not reversible.

[0004] One of the aims of the invention is to propose a method for assembling and fixing a screen on a frame ensuring reliable immobilization of the screen on the frame in a reversible manner and not applying stress likely to generate display defects on the display surface of the display device.

[0005] To this end, the invention relates to an assembly method of the aforementioned type, in which the method comprises the following successive steps:

[0006] - assembly of a screen comprising a display face with a sealing gasket thus forming a central whole;

[0007] - fixing a frame with a lens thus forming a front assembly;

[0008] - assembly of the central assembly with the front assembly, the lens being po located opposite the display face of the screen, the seal maintaining a sealed connection between the lens and the screen and forming a spacer maintaining a space between the screen and the lens, the seal comprising at least one injection opening comprising an internal orifice opening into the space and an external orifice adapted to receive an injector tip of a transparent glue; and

[0009] - injecting said transparent glue into the space through the injection opening.

[0010] The method of assembling the fixing device according to the invention makes it possible to effectively lock the screen on the frame and in particular to prevent a modification of the position of the screen relative to the frame, without applying stresses to the screen. Indeed, these stresses are absorbed by the sealing gasket. Thus, the quality of the display on the display surface is preserved. In addition, by reducing the stresses applied to the screen, the risks of delamination of the optical bonding between the screen and the lens are reduced.

[0011] The assembly method according to the invention may comprise one or more of the following characteristics, considered alone or in any technically conceivable combination:

[0012] - the seal is present all around the screen, and creates a sealing between the screen and the frame;

[0013] - the seal has lips all around its perimeter, positioned to be in contact with the screen;

[0014] - the frame comprising a support column, the sealing gasket forming a cylindrical portion surrounding the support column around the entire perimeter of the column, the injection opening being provided in the cylindrical portion;

[0015] - an injection valve located near the external orifice of the opening injection, the injection valve being suitable for only allowing the passage of fluid from the external orifice to the internal orifice;

[0016] - the seal further comprises a ventilation opening passing through the seal sealing, the ventilation opening comprising an internal orifice opening onto the space and an external orifice;

[0017] - a vent valve located near the outer orifice of the opening ventilation, the ventilation valve being suitable for allowing only the passage of fluid from the inner orifice to the outer orifice;

[0018] - the space is in contact only with the lens, the screen and the sealing gasket.

[0019] According to another aspect, the invention also relates to a display device comprising a screen, a frame and a lens, the lens being positioned opposite a display face of the screen, the frame surrounding the screen and the lens being fixed to the frame, characterized in that the display device comprises a seal fixed to the frame and to the screen, adapted to maintain a sealed connection between the lens and the screen and forming a spacer to maintain a space between the screen and the lens, the display device comprising at least one injection opening passing through the seal, the injection opening comprising an internal orifice opening into the space and an external orifice adapted to receive a transparent glue injector tip, the space being adapted to receive a transparent glue.

[0020] According to other aspects, the invention also relates to a manufacturing assembly with several housings each allowing to receive a display device assembled with an assembly method, the manufacturing assembly comprising an injector device allowing to inject glue into each external orifice of each sealing joint.

[0021] According to other aspects, the invention also relates to a method of manufacturing a plurality of display devices using a manufacturing assembly, the method comprising the following successive steps:

[0022] - positioning of several display devices in the manufacturing assembly;

[0023] - connection of the injector device to each external orifice;

[0024] - injecting glue into the space of each of the display devices through the orifice external of each seal.

[0025] Other aspects and advantages of the invention will appear on reading the following description, given by way of example and with reference to the appended drawings, in which:

[0026] [Fig-1] - [Fig.l] is a partial sectional view of an injection opening of a display device assembled according to an assembly method according to the invention,

[0027] [Fig.2] - [Fig.2] is a partial sectional view of the injection opening of a display device according to another embodiment with a glue injector,

[0028] [Fig.3] - [Fig.3] is a top view of the display device of [Fig.l],

[0029] [Fig.4] - [Fig.4] is a sectional view of the display device of [Fig.l] during a step of the assembly method according to the invention,

[0030] [Fig.5] - [Fig.5] is a sectional view of the display device of [Fig.l] during another step of the assembly method according to the invention,

[0031] [Fig.6] - [Fig.6] is a sectional view of the display device of [Fig.l] during yet another step of the assembly method according to the invention, and

[0032] [Fig.7] - [Fig.7] is a sectional view of a manufacturing assembly comprising a plurality of display devices of [Fig.l].

[0033] With reference to Figures 1 and 2, a display device 10 is described. The process of assembling such a display device 10 will be described below.

[0034] Such a display device 10 is for example intended to be mounted in the passenger compartment of a vehicle, so as to display information related to the state of the vehicle and / or its driving and / or to display audiovisual content. The display device 10 is for example mounted on a trim element of the passenger compartment, such as a dashboard, a door panel, a central console, a seat, an armrest or the like.

[0035] The display device 10 comprises a frame 12 and a lens 14, the lens 14 being fixed to the frame 12. The display device 10 further comprises a screen 16 and a seal 18 fixed to the frame 12 and to the screen 16.

[0036] The screen 16 being connected to the frame 12 by the seal 18, the seal 18 framing the screen 16 and the seal 18 being framed by the frame 12.

[0037] The lens 14 is positioned opposite a display face of the screen 16.

[0038] A shape of the frame 12 is shown as an example in [Fig. 3], the frame 12 advantageously forming a rectangular crown surrounding the seal 18. The crown being centered on an elongation axis XX substantially perpendicular to the plane in which the frame extends. The frame 12 thus defines an opening having a shape substantially complementary to the contour of the seal 18.

[0039] The frame 12 is arranged to receive the screen 16 and the seal 18 in said opening and to provide the interface between the display device 10 and the environment of the display device 10 in the vehicle. In other words, the frame 12 is mounted on the trim element receiving the display device 10, for example in an opening of the trim element provided for this purpose.

[0040] The frame 12 advantageously comprises at least in two places, a projection 26 in the shape of an arc of a circle. As visible in [Fig.3], the projections 26 are each positioned in a corner of the rectangular frame 12.

[0041] The frame 12 also comprises at least two support columns 28, each advantageously positioned at the center of the arc of a circle defining the projection 26, in a corner of the frame 12. The support column 28 is connected to the frame 12 at the base of the column, not shown in Figures 1 and 2.

[0042] The frame 12 comprises a fixing surface 30 with a closed contour, oriented orthogonally to the elongation axis XX. The lens 14 is positioned against the fixing surface 30.

[0043] The lens 14 extends mainly in a direction perpendicular to the elongation direction XX. The lens 14 has an inner face 32 oriented towards the screen 16 and an outer face 34 opposite the inner face 32.

[0044] In an embodiment not shown, the inner face 32 of the lens 14 is curved.

[0045] The lens 14 is fixed to the frame 12 using a rim of glue 36 applied at least to a portion of the fixing surface 30 of the frame 12 and to an inner face 32 of the lens 14.

[0046] As seen in [Fig.l], the frame 12 follows the periphery of the lens 14 and the opening of the frame 12 has a shape substantially complementary to the lens 14. The lens 14 forms the display surface of the display device 10 and protects the screen 16, the lens 14 extending into the opening of the frame 12 and closing this opening.

[0047] The seal 18 is adapted to maintain a sealed connection between the screen 16 and the lens 14 and to form a spacer to maintain a space 37 between the screen 16 and lens 14.

[0048] The seal 18 is a crown centered on the elongation axis XX, made of deformable plastic material. The seal 18 has an internal contour 38 and an external contour 40. The internal contour 38 is pressed against the peripheral edge of the screen and matches the shape of the latter. The external contour 40 is pressed against the internal surface of the frame 12 and therefore has a shape corresponding to that of the opening of the frame 12.

[0049] The seal 18 comprises a cylindrical portion 42 suitable for matching the shape of the gap between the support column 28 and the projection 26. As shown in [Fig. 3], the seal 18 surrounds the support column 28 over the entire perimeter of the support column 28.

[0050] Figures 1 and 2 show a sectional view in which the base of the support column 28 is not visible and the cylindrical portion 42 is shown instead.

[0051] The seal 18 comprises at least one injection opening 44, advantageously arranged in the cylindrical portion 42 of the seal 18. The injection opening 44 comprises an internal orifice 46 opening into the space 37 and an external orifice 48, the injection opening 44 passing through the seal 18. The injection opening 44 is thus of cylindrical shape seen in the plane of [Fig.3].

[0052] In one embodiment, visible in [Fig. 1], the injection opening 44 has a bent shape. In another embodiment, visible in [Fig. 2], the injection opening 44 has a straight shape.

[0053] The external orifice 48 is located at the distal end of the cylindrical portion 42 of the seal 18. The external orifice 48 is adapted to receive a transparent glue injector tip 50, as shown in [Fig.2].

[0054] The display device 10 further comprises an injection valve 52 located near the external orifice 48, in the injection opening 44. The injection valve 52 being capable of only allowing the passage of fluid from the external orifice 48 to the internal orifice 46.

[0055] In [Fig.l], the injection valve 52 is visible but in [Fig.2], another embodiment without injection valve 52 is shown.

[0056] In an embodiment not shown, the injection opening 44 is split into two pipes passing through the sealing joint 18, on each side of the support column 28.

[0057] The seal 18 also includes a ventilation opening 54, visible in [Fig. 3] passing through the seal 18 and putting the space 37 into fluid communication with the exterior. The ventilation opening 54 is advantageously located opposite the injection opening 44 relative to the elongation axis XX.

[0058] The ventilation opening 54 comprises an internal orifice 56 opening onto the space 37 and an external orifice 58 opening into the environment of the display device.

[0059] Alternatively, the display device 10 further comprises a ventilation valve located near the external orifice 58 in the ventilation opening 54. The ventilation valve being capable of only allowing the passage of fluid from the internal orifice 56 to the external orifice 58.

[0060] The vent opening 54 is similar to the injection opening 44, [Fig.l] representing one of the injection opening 44 or the vent opening 54.

[0061] The internal contour 38 of the seal 18 has a shape that is substantially complementary to the contour of the screen 16. The seal 18 also has lips 62 located on its internal contour 38, suitable for ensuring the sealing of the connection of the seal 18 to the screen 16. The lips 62 are visible in FIGS. 1 and 2, but in the position of the display device 10 shown, the lips 62 are pressed between the seal 18 and the screen 16.

[0062] The seal 18 is present around the entire circumference of the screen 16, creating a seal between the screen 16 and the frame 12. The lips are also present around the entire internal contour 38 of the seal 18.

[0063] In an embodiment not shown, the seal 18 also comprises on its external contour 40 lips intended to be positioned against the frame 12.

[0064] The screen 16 extends mainly in a direction perpendicular to the elongation direction XX. The screen 16 is fixed via the seal 18 to the frame 12. The screen 16 has an inner surface 64 facing the lens 14 and an outer surface 66 opposite the inner surface 64.

[0065] The inner surface 64 is typically a display face of the screen.

[0066] In an embodiment not shown, the inner surface 64 of the screen 16 is curved.

[0067] The invention applies to any type of screen 16, such as an LCD screen (for “Liquid Crystal Display”) or OLED screen (for “Organic Light-Emitting Diodes”).

[0068] According to one embodiment, the screen 16 is a touch screen making it possible to control functions of the display device 10 and / or the vehicle in which the display device 10 is mounted by digital contact with the display surface. To do this, a capacitive film is for example applied to the outer face 34 of the lens 14.

[0069] In one embodiment, shown in [Fig.4] the screen is connected to a PCB (for “Printed Circuit Board”) advantageously comprising a graphics microcontroller.

[0070] The space 37 provided between the lens 14 and the screen 16 is maintained at a thickness constant by means of the sealing gasket 18. In other words, the respective positions of the lens and the screen relative to each other are kept unchanged by the sealing gasket.

[0071] In the case where the inner surface 64 of the screen 16 is curved or the inner face 32 of the lens 14 is curved, the gap 37 is also kept constant throughout the assembly process described below.

[0072] The space 37 is advantageously delimited solely by the lens 14, the screen 16 and the sealing gasket 18.

[0073] The display device 10 also comprises a frame 68 shown in [Fig.2]. The frame 68 is fixed to the frame 12 and to the screen 16 and provides a connection with the external environment of the display device 10. The frame 68 partially blocks the screen 16 in the direction of elongation XX.

[0074] The display device 10 also comprises a shell 70 shown in [Fig.6], fixed to the frame 68. The shell 70 immobilizes the frame 68 and therefore the screen 16 in the direction of elongation XX. The shell 70 is positioned against a bottom of the vehicle trim element.

[0075] A liquid optical glue fills the space 37. It is injected through the injection opening(s) 44, as described below.

[0076] It completely fills space 37.

[0077] The glue in particular covers the display face of the screen 16, and covers the inner face 32 of the lens 14. It contributes to holding the lens 14 in position relative to the screen 16.

[0078] The assembly process will now be described.

[0079] Beforehand, in a first step 100, the screen 16 and the sealing gasket 18 are assembled.

[0080] The screen 16 for this purpose is introduced into the internal contour 38 of the seal 18. The lips 62 of the seal 18 are deformed to accommodate the screen 16.

[0081] The screen 16 and the seal 18 form a central assembly 72.

[0082] During this same step 100, the lens 14 is fixed to the frame 12.

[0083] A rim of glue 36 is applied to at least a portion of the fixing surface. 30 and lens 14 is applied on it.

[0084] The lens 14 and the frame 12 form a front assembly 74.

[0085] The central assembly 72 and the front assembly 74 are visible in [Fig.4].

[0086] In a following step 200, the central assembly 72 is assembled to the front assembly 74, the lens 14 being positioned opposite the display face of the screen 16.

[0087] The central assembly 72 is introduced in the direction of elongation XX so that the seal 18 comes into abutment against the lens 14. The seal 18 is placed on the frame 12, the cylindrical portions of the seal 18 surrounding the support columns 28 of frame 12.

[0088] The seal 18 maintains a sealed connection between the lens 14 and the screen 16 and forms a spacer maintaining a space 37 between the screen 16 and the lens 14.

[0089] The seal 18 maintains a sealed connection between the screen 16 and the frame 12.

[0090] The frame 68 is then fixed to the frame 12, thanks to the support columns 28 as shown in [Fig.5] or by coming into abutment against the sealing gasket 18 as shown in [Fig.2].

[0091] Two jaws 76 are then applied on either side of the display device 10 in the direction of elongation XX, ensuring an absence of movements in the direction of elongation XX. The jaws 76 are visible in [Fig.5].

[0092] In a next step, a transparent glue 78 is injected through the injection opening 44 into the space 37.

[0093] To do this, the tip 50 of a glue injector is fixed to the external orifice 48 of the injection opening 44 of the seal 18. Such an injector is partially shown in [Fig.2].

[0094] The two jaws 76 and the glue injector together form a manufacturing unit 77.

[0095] The jaws 76 firmly hold the display device 10 in place, the injector injects the transparent glue 78 through the injection opening 44 into the space 37.

[0096] The transparent glue 78 is for example a Liquid Optically Clear Adhesive (LOCA).

[0097] The transparent glue 78 fills the entire space 37 and the injection opening 44. The ventilation opening 54 is advantageously partly filled with the transparent glue 78. The injection valve 52 prevents the glue from escaping through the injection opening 44. The ventilation valve prevents the glue from escaping through the ventilation opening 54, while allowing the transparent glue 78 to dry.

[0098] In a following step 300, when the transparent glue 78 is polymerized, the jaws 76 are removed from the display device 10 and the shell 70 is positioned on the frame 68. The display device 10 being assembled, as visible in [Fig.6].

[0099] [Fig.7] illustrates a manufacturing assembly 80 for display devices. The manufacturing assembly 80 comprises several housings 82, each allowing a display device 10 to be received assembled using the assembly method described above.

[0100] Each housing 82 accommodates a manufacturing unit 77 in which the display device is received. This comprises the screen 16, the frame 12, the seal 18 and the lens 14 already assembled to each other (situation of [Fig.l]).

[0101] The manufacturing assembly 80 also comprises an injector device 84 for injecting glue into each external orifice 48 of each seal 18.

[0102] This injector device 84 comprises a plurality of conduits 86 and a reservoir 88 of transparent glue 78, the plurality of conduits connecting the reservoir 88 to the glue injectors of each manufacturing unit 77.

[0103] The injector device 84 also comprises a plurality of pumps 90 positioned on the conduits 86. Taps not shown are present upstream of the external orifice 48 of each sealing joint 18.

[0104] The corresponding manufacturing process is now briefly described.

[0105] In a first step, several display devices 10 are positioned in the manufacturing assembly 80.

[0106] More precisely, they are each positioned in a manufacturing unit 77.

[0107] In a second step, the injector device 84 is connected to the external orifices 48 of each display device 10.

[0108] To do this, the tips 50 of the glue injectors are engaged in the external orifices 48 of the injection openings 44.

[0109] Thus, the conduits 86 are connected to the external orifices of the sealing joints.

[0110] In a third step, transparent glue 78 is injected from the reservoir 88 into the space 37 of each of the manufacturing units. Once the transparent glue 78 has polymerized, the manufacturing unit 77 is removed from the housings 82 of the manufacturing assembly 80.

[0111] The assembly process has multiple advantages.

[0112] The presence of the sealing gasket 18 makes it possible to maintain a constant space 37 between the lens 14 and the screen 16 during the polymerization of the glue, while absorbing shocks thanks to its deformable plastic composition.

[0113] The shape of the seal 18 is adaptable to the shape of the screen 16 and is functional even in the case of a screen 16 having a curved interior surface 64. Whatever the shape of the space 37, the seal 18 makes it possible to maintain a constant distance between the screen 16 and the lens 14.

[0114] Since the seal 18 is simple and inexpensive to manufacture, the assembly process is thus simplified and inexpensive.

[0115] The assembly process also involves few steps and is easy to implement.

[0116] The placement of the injection opening 44 on one end of the seal 18 allows easy access to the space 37 and facilitated connection with the clear glue injector tip 50.

[0117] The sealing gasket 18 frames the entire screen 16 and has lips 62 over its entire internal contour 38 ensuring sealing between the screen 16 and the frame 12 without transmission of mechanical forces.

[0118] The presence of a support column 28 allows the sealing gasket 18 to be fixed to the frame 12 easily and quickly.

[0119] The injection valve 52 prevents the transparent glue 78 from flowing out of the injection opening 44 during the drying of the glue. The vent valve prevents the transparent glue 78 from flowing out of the vent opening 54 during the polymerization of the glue.

[0120] The ventilation opening 54 is positioned opposite the injection opening 44 in order to precisely dose the transparent glue 78 to be injected into the space 37, the transparent glue 78 first filling the entire space 37 without it rising directly into the ventilation opening 54.

[0121] The space 37 intended to receive the transparent glue 78 is in contact only with the screen 16 and the lens 14 which are the elements to be glued together, but also with the sealing joint 18 ensuring the space 37 between the screen 16 and the lens 14.

[0122] The manufacturing assembly 80 and the manufacturing method allow for a modular manufacturing mode that is simple to use while manufacturing a larger number of display devices 10 simultaneously. The drying time of each manufacturing unit 77 being similar, the time of a manufacturing cycle of a display device 10 is thus optimized.

Claims

Claims

1. Method of assembling a display device (10), characterized in that the method comprises the following successive steps: - assembling a screen (16) comprising a display face with a seal (18) thus forming a central assembly (72); - fixing a frame (12) with a lens (14) thus forming a front assembly (74); - assembly of the central assembly (72) with the front assembly (74), the lens (14) being positioned opposite the display face of the screen (16), the seal (18) maintaining a sealed connection between the lens (14) and the screen (16) and forming a spacer maintaining a space (37) between the screen (16) and the lens (14), the seal comprising at least one injection opening (44) comprising an internal orifice (46) opening into the space (37) and an external orifice (48) adapted to receive a tip (50) of an injector of a transparent glue (78);and - injecting said transparent glue (78) into the space (37) through the injection opening (44), the frame (12) comprising a support column (28), the seal (18) forming a cylindrical portion (42) surrounding the support column (28) over the entire perimeter of the column, the injection opening (44) being provided in the cylindrical portion (42).;

2. An assembly method according to claim 1, wherein the seal (18) is present around the entire perimeter of the screen (16), and creates a seal between the screen (16) and the frame (12).

3. An assembly method according to claim 2, wherein the seal (18) comprises lips (62) around its entire circumference, positioned to be in contact with the screen (16).

4. An assembly method according to any one of the preceding claims, further comprising an injection valve (52) located near the external orifice (48) of the injection opening (44), the injection valve (52) being capable of only allowing the passage of fluid from the external orifice (48) to the internal orifice (46).

5. An assembly method according to any one of the preceding claims, wherein the seal (18) further comprises a vent opening (54) passing through the seal (18), the vent opening (54) having an inner orifice (56) opening into the space (37) and an outer orifice (58).

6. The assembly method of claim 5, further comprising a vent valve located proximate the outer orifice (58) of the vent opening (54), the vent valve being adapted to only allow the passage of fluid from the inner orifice (56) to the outer orifice (58).

7. An assembly method according to any preceding claim, wherein the gap (37) is in contact only with the lens (14), the screen (16) and the seal (18).

8. A display device (10) comprising a screen (16), a frame (12) and a lens (14), the lens (14) being positioned opposite a display face of the screen (16), the frame (12) surrounding the screen (16) and the lens (14) being fixed to the frame (12), characterized in that the display device (10) comprises a seal (18) fixed to the frame (12) and to the screen (16), adapted to maintain a sealed connection between the lens (14) and the screen (16) and forming a spacer for maintaining a space (37) between the screen (16) and the lens (14), the display device (10) comprising at least one injection opening (44) passing through the seal (18), the injection opening (44) comprising an internal orifice (46) opening into the space (37) and an external orifice (48) adapted to receive a tip (50) of a transparent glue injector, the space (37) being adapted to receive a transparent glue (78),the frame (12) comprising a support column (28), the seal (18) forming a cylindrical portion (42) surrounding the support column (28) over the entire perimeter of the column, the injection opening (44) being provided in the cylindrical portion (42).,

9. Manufacturing assembly (80) with a plurality of housings (82) each for receiving a display device (10) assembled with an assembly method according to any one of claims 1 to 7, the manufacturing assembly (80) comprising an injector device (84) for injecting glue into each external orifice (48) of each seal (18).

10. A method of manufacturing a plurality of display devices using a manufacturing assembly (80) according to claim 9, the method comprising the following successive steps: - positioning several display devices in the manufacturing assembly (80); - connecting the injector device (84) to each external orifice (48); - injecting glue into the space (37) of each of the devices display through the external orifice (48) of each seal (18).

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