JP6201321B2 - Display device - Google Patents

Description

  The present invention relates to an improvement in a grounding structure of a display device that displays predetermined information on a display, and particularly relates to a display device in which a protective member is bonded to the front side of a display display with a transparent resin.

  A conventional display device is, for example, as disclosed in Patent Document 1, a display element (display display) that displays predetermined information, and a display plate (protective member) disposed on the front side of the display element so as to cover the display element. ) Is bonded by an optical adhesive filled in a gap formed between the display element and the display plate, thereby eliminating an air gap between the display element and the display plate. The visibility of the display element is improved by reducing reflected light due to external light emitted from the display element and improving the transmittance of display light emitted from the display element to the front surface side.

  By the way, in such a display device, in order to remove a static charge charged on the display plate or the display element so that the display element does not malfunction due to static electricity (static charge) generated on the display plate, Some must be grounded (also known as ground or ground connection).

  As described above, as disclosed in Patent Document 2, as a method for grounding, a metal on-board contact is disposed between the display board and the wiring board, and the display board and the wiring board (ground terminal) are provided. There is something that makes the continuity.

  Further, as disclosed in Patent Document 3, there is one that electrically connects a display element and a wiring board (ground terminal) by compressing and holding a conductive rubber between the display element and the wiring board. .

JP 2011-022523 A JP 2010-127800 A JP 61-177480 A

  When the display element is not bonded to the display board with an optical adhesive as in Patent Document 1, the display element is an intermediate case that is sandwiched between the display board and the wiring board as described in Patent Document 2 ( It is fixed to the wiring board by a holder. In such a configuration, when vibration is applied to the display device, even if an on-board contact as disclosed in Patent Document 2 is provided between the display element and the wiring board, the display element is provided between the display element and the wiring board. Even if the conductive rubber is compressed and sandwiched as in Patent Document 3, the display element and the wiring board are substantially synchronized with each other because the display element is fixed to the wiring board. It is hard to be loaded by vibration.

  However, when the display element is bonded to the display board with an optical adhesive as in Patent Document 1, the display element is not fixed to the wiring board. Therefore, when vibration is applied to the display device, the display element and the wiring board If the on-board contact is arranged between the display element and the wiring board, the display element or the on-board contact may be damaged due to friction between the display element and the on-board contact. there were. In addition, there is a possibility that the joint portion between the on-board contact and the wiring board may be damaged by the stress due to the friction between the display element and the on-board contact.

  Similarly, in the configuration in which the display element is bonded to the display board with an optical adhesive, when conductive rubber is compressed and sandwiched between the display element and the wiring board, there is no escape from stress due to vibration, and the display element and the optical adhesive There was a possibility that the joint portion between the agent and the conductive rubber would be fatigued.

  Therefore, the present invention has been made in view of such problems in the conventional technology, and provides a display device capable of suppressing malfunction caused by static electricity while reducing the burden caused by vibrations applied to the component parts. It is intended.

The present invention includes a display unit having a display element for displaying predetermined information, a conductive frame covering the display unit, a wiring board disposed on the bottom side of the frame and having a ground connection portion, and the frame A columnar conductive elastic body that electrically connects the bottom surface of the conductive layer and the ground connection portion, and a standing wall that engages with the wiring board, covers substantially the entire circumference of the side surface of the conductive elastic body, and is shorter than the conductive elastic body And a fixing portion that holds the distal end of the conductive elastic body on the display means side so as to be deformable against a deviation between the display means and the wiring board .

Further, in the present invention, a display means having a display element for displaying predetermined information, a conductive frame covering the display means, a wiring board disposed on the bottom side of the frame and having a ground connection portion, A columnar conductive elastic body that electrically connects the bottom surface of the frame and the ground connection portion, and is disposed between the display means and the wiring board, covering substantially the entire circumference of the side surface of the conductive elastic body, A standing wall portion shorter than the conductive elastic body is formed, and a fixed portion is formed in part to hold the tip of the conductive elastic body on the display means side in a deformable manner with respect to a shift between the display means and the wiring board And a middle case .

In the present invention, a plate-like display plate joined to the display surface side of the display means is further provided, and the middle case holds the display plate.

  ADVANTAGE OF THE INVENTION According to this invention, the display apparatus which can suppress the malfunctioning by static electricity can be provided, reducing the burden by the vibration concerning a component.

The front view of the meter for vehicles in the embodiment of the present invention. AA sectional drawing of FIG. The expanded sectional view which expands and shows the principal part of FIG. The figure which shows the relationship between the electrically conductive rubber and grounding land of the embodiment. The perspective view of the grounding means of the embodiment. The top view of the grounding means of the embodiment.

  Hereinafter, based on FIGS. 1-3, the case where the display apparatus of this invention is applied to the vehicle instrument mounted in a vehicle is mentioned as an example, and is demonstrated. FIG. 1 is a front view of a vehicle instrument according to the present embodiment, and FIG. 2 is a cross-sectional view of the vehicle instrument and is a cross-sectional view taken along line AA of FIG. FIG. 3 is an enlarged cross-sectional view in which the main part of FIG. 2 is enlarged.

  1 and 2, a vehicle instrument 1 is arranged in an instrument panel in front of a driver's seat of an automobile and displays various vehicle information. For example, a resin case (upper case 10, lower case) In the case 20), a pointer instrument 30 that rotates according to detection information (vehicle speed), a liquid crystal display unit 40 that displays various information of the vehicle in characters, figures, etc., a display board 50, a wiring board 60 comprising a printed board, etc. Is housed. The wiring board 60 is formed of, for example, a glass epoxy board or the like, inputs vehicle information from the external connector 61 (FIG. 2), outputs the result of arithmetic processing of the vehicle information as a control signal, and outputs the pointer instrument 30 or the liquid crystal A control unit 62 for controlling the display unit 40 is provided, and the vehicle meter 1 is electrically controlled.

  In the following description, in order to facilitate understanding of the configuration of the vehicle instrument 1, the viewer direction (upward direction in FIG. 2) of the vehicle instrument 1 is the front side, and the opposite direction (downward direction in FIG. 2). The back side. The outer peripheral direction (left-right direction in FIG. 2) from the center of the vehicle instrument 1 is the outside, and the direction from the outer periphery to the center of the vehicle instrument 1 (the left-right center direction in FIG. 2) is the inner side.

  The upper case 10 includes a see-through cover member 11 made of a light-transmitting synthetic resin and a partition member 12 made of a light-blocking synthetic resin such as black. The partition member 12 is fitted with a see-through cover member 11 so as to cover the front side thereof, and is attached to a lower case 20 described later so as to cover the front side of various display units (the pointer instrument 30, the liquid crystal display unit 40, the display board 50). Removably assembled.

  The fluoroscopic cover member 11 is provided with a plurality of locking portions 110 integrally with a predetermined interval at appropriate positions on the outer peripheral portion. The locking portion 110 is formed by an elastic arm piece 111 that protrudes integrally from the outer peripheral portion of the fluoroscopic cover member 11 toward the back side, and a claw-like hook portion 112 provided at the distal end portion of the elastic arm piece 111. It is formed. The fluoroscopic cover member 11 is removably engaged with the front side of the partition member 12 by inserting a part of the hook portions 112 into an engagement portion 120 of the partition member 12 to be described later, and the other hook portions 112 are engaged. Then, it is engaged with the front side of the lower case 20 by being inserted into an engaging portion 210 of the lower case 20 described later.

  The partition member 12 is integrally provided with a frame-like engagement portion 120 for receiving the locking portion 110 at a position facing some of the locking portions 110 provided on the fluoroscopic cover member 11, and the fluoroscopic cover member. 11, a locking portion 121 including an elastic arm piece 122 and a hook portion 123 is integrally provided at a predetermined position on the outer peripheral portion of the partition member 12 with a predetermined interval. The partition member 12 is detachably engaged with the front side of the lower case 20 by inserting the hook portion 123 into an engaging portion 210 of the lower case 20 described later. Moreover, the partition part 12 has the shielding part 124 extended toward inner side, and this shielding part 124 visually recognizes the opening part 124a which can visually recognize the liquid crystal display unit 40, the pointer instrument 30, and the display board 50. An opening 124b that can be provided.

  The lower case 20 has an outer periphery for receiving the engaging portions 110 (elastic arm pieces 111 and hook portions 112) of the see-through cover member 11 and the engaging portions 121 (elastic arm pieces 122 and hook portions 123) of the facing member 12. An engaging portion 210 having a frame shape is provided at the portion, and a mounting portion 220 that protrudes from the bottom surface portion of the lower case 20 toward the front surface (in the direction of the wiring board 60).

  The pointer instrument 30 includes a pointer 31 that can be controlled to emit light disposed on the front side of the display board 50, which will be described later, a movement 32 that is mounted on a wiring board 60 that is positioned on the back side of the display board 50 that rotates the pointer 31, The movement 32 is provided with a rod-shaped shaft 32a through which a pointer hole (not shown) of the display plate 50 is inserted from the movement 32 to the pointer 31, and the pointer 31 is attached to the tip. It is driven to rotate the pointer 31 to a predetermined position, and an indicator portion (scale or number) of the display board 50 to be described later is indicated.

The liquid crystal display unit 40 includes a liquid crystal display composed of TFT type liquid crystal devices, a backlight, a display 41 mainly composed of a light guide that guides light from the backlight toward the liquid crystal display, and a display And a metal frame 42 for storing 41 with the display surface of the liquid crystal display exposed. The liquid crystal display inputs an electrical signal through flexible wiring with a wiring board 60 (not shown), and displays various information such as remaining fuel information, trip value, average fuel consumption, and audio information based on this signal.
The liquid crystal display unit 40 is bonded to a predetermined position on the back side of the display plate (protective member) 50 by a transparent optical adhesive B based on a resin.

  As shown in FIG. 3, a display plate (protective member) 50 covering the liquid crystal display unit 40 includes a flat plate-like translucent substrate 51 made of polycarbonate as a base material, and a rear side of the translucent substrate 51. A non-transmissive portion 52 made of a black light-shielding layer that is printed by cutting out a region where the display region of the liquid crystal display unit 40 faces, and a translucent substrate 51 (display region of the liquid crystal display unit 40) that is a bonding region using an optical adhesive. A non-transparent portion notched region), and a non-transparent portion 52 around the notch region, and an adhesive strength-enhancing layer (adhesive strength-enhancing portion) 53. The impermeable portion 52 also has a function as a concealing portion that makes the portion other than the display area of the liquid crystal display unit 40 invisible when the vehicular instrument 1 is viewed from the front side. The impermeable portion 52 may be a printed layer having a pattern such as a gradation.

  Although not described in detail here, the opaque portion 52 is continuously provided not only on the liquid crystal display unit 40 side but also on the pointer instrument 30 side. Is printed on the back surface of the translucent substrate 51 excluding the region where the above-described indicator portion (numbers, scales, etc.) is formed, and a light source (not shown) provided on the wiring board 60 with the display board 30. By illuminating, the viewer can visually recognize the indicator portion.

  The wiring board 60 is made of, for example, a hard wiring board in which a wiring pattern is applied to a glass epoxy base material, and is in contact with the movement 32, the external connector 61, the control unit 62, and the back surface of the metal frame of the liquid crystal display unit 40 described above. Means 63 and the like. The mounting portion 220 of the lower case 20 is in contact with the back side of the wiring board 60 and is fixed to the lower case 20 (mounting portion 220) by a fixing means such as a screw or a hook. The grounding means 63 will be described in detail later.

  Further, an intermediate case 70 made of, for example, a white synthetic resin is provided on the front side of the wiring board 60. The case body 70 houses a light source (not shown) and transmits the light to the pointer 32 and A plurality of illumination rooms are formed to guide the display panel 50 side. The middle case 70 has a function as a holding body that holds the display panel 50.

  In the vehicle instrument 1 in the present embodiment configured as described above, the assembly is performed as follows. First, a fixing portion 631 of a grounding means 63 to be described later is fixed to the wiring substrate 60 on which circuit components are first mounted, and the wiring substrate 60 is fixed to the lower case 20 (mounting portion 220). Next, the middle case 70 is set on the lower case 20 so as to be on the front side of the wiring board 60, conductive rubber 630 of a grounding means 63 described later is inserted into the fixing portion 631, and the wiring of the liquid crystal display unit 40 is connected to the wiring board. After connecting to 60, the display plate 50 to which the liquid crystal display unit 40 is joined is set on the front side of the middle case 70. Subsequently, the base side of the pointer 31 is press-fitted and fixed to the distal end side of the shaft 32 a provided in the movement 32 of the pointer instrument 30. Thereby, the display board 50 which joined the wiring board 60, the middle case 70, and the liquid crystal display unit 40 on the basis of the lower case 20 is set in a laminated state. Further, by attaching the see-through cover member 11 and the look-back member 12 serving as the upper case 10 so as to overlap the lower case 20 side, the locking portions 110 and 121 provided on the see-through cover member 11 and the look-back member 12 respectively. It is fed along the frame-shaped engaging portion 210 provided on the lower case 20 side, and the hook portions 112 and 123 provided in the respective locking portions 110 and 121 engage with the frame-shaped engaging portion 210 and come off. Stopped and held.

  At this time, since the liquid crystal display unit 40 is not directly fixed to the wiring board 60, when the vehicle instrument 1 vibrates, a vibration occurs between the liquid crystal display unit 40 and the wiring board 60, and the liquid crystal A load is applied to the grounding means 63 in contact with both the display unit 40 and the wiring board 60. However, the grounding means 63 of the present invention reliably grounds the metal frame 42 of the liquid crystal display unit 40 while reducing the burden caused by vibrations on the components (the liquid crystal display unit 40, the wiring board 60, and the conductive rubber 630). Thus, malfunction of the liquid crystal display due to static electricity can be suppressed. Hereinafter, the grounding means 63 in the present embodiment will be described with reference to the drawings. 4 is a diagram comparing the conductive rubber 64 and the grounding lands E of the wiring board 60, FIG. 5 is a perspective view of the grounding means 63, and FIG. 6 is a top view of the grounding means 63.

  The grounding means 63 is disposed between the liquid crystal display unit 40 and the wiring board 60, and grounds the electrostatic charge of the metal frame 42 to the ground land E of the wiring board 60. The grounding means 63 includes a conductive rubber (conductive elastic body) 630 that conducts the metal frame 42 and the ground land E, and a fixing portion 631 that positions the conductive rubber 630 with respect to the wiring board 60.

  The conductive rubber (conductive elastic body) 630 is a silicone rubber or the like that is provided with conductivity by blending a conductive material such as carbon, and is a rectangular parallelepiped whose longest side extends between the liquid crystal display unit 40 and the wiring board 60. One end is in contact with the metal frame 42 of the liquid crystal display unit 40, and the other end is in contact with the ground land E of the wiring board 60 to ground the metal frame 42.

  The conductive rubber 630 is assembled between the liquid crystal display unit 40 and the wiring board 60 in a slightly compressed state. By assembling in such a slightly compressed state, the metal frame 42 can be reliably grounded. In addition, the conductive rubber 630 has a small cross section in the horizontal direction of the wiring substrate 60, and thus the shape thereof is easily changed. Even when the liquid crystal display unit 40 and the wiring substrate 60 vibrate differently, the shape of the conductive rubber 630 is changed. 40, the load applied to the wiring board 60 and the conductive rubber 630 itself can be reduced. Further, the conductive rubber 630 is formed smaller than the ground land E as shown in FIG. As a result, even if the conductive rubber 630 deviates from a predetermined location on the wiring board 60, it can be reliably grounded. Further, the conductive rubber 630 is positioned with respect to the wiring board 60 by being inserted into the fixing portion 631 as described later. Further, the shape of the conductive rubber 630 is not limited to a rectangular parallelepiped, and may be a cylindrical shape or other prismatic shape.

  The fixing portion 631 has a flange shape formed of a synthetic resin, and protrudes in the direction of the metal frame 42 from the flange portion 632 having a screw hole 632a for screwing to the wiring board 60. It has a cylindrical portion 633 having an insertion hole 633a for inserting the conductive rubber 630, and a screw 634 that is inserted into the screw hole 632a and fixes the fixing portion 631 and the wiring board 60.

  The insertion hole 633a is wider than the conductive rubber 630, so that the conductive rubber 630 can be further deformed and can be moved to some extent in the insertion hole 633a. Further, the length of the cylindrical portion 633 is shorter than that of the conductive rubber 630. With such a configuration, it is possible to prevent wear and damage due to the fixing portion 631 coming into contact with the metal frame 42, and further, the conductive rubber 630. Only the front end portion of the metal frame 42 is easily deformed, and deformation of the other portions of the conductive rubber 630 is relatively small, so that the conductive rubber 630 is prevented from being extremely deformed, and the wiring board 60 (ground land) The connection between the conductive rubber 630 and the metal frame 42 can be maintained well while the connection with E) is reliably performed. In addition, the fixing portion 631 is fixed to the wiring board 60 with screws 634, but is not limited thereto, and may be fixed to the wiring board 60 with hooks or the like. Further, an insertion hole for inserting the conductive rubber 630 may be provided in a part of the middle case 70 so that the conductive rubber 630 may be positioned with respect to the wiring board 60. Thus, by using a part of the middle case 70, the number of parts can be reduced and the number of assembly steps can be reduced. Further, the insertion hole 633a does not cover the entire side surface of the conductive rubber 630, but may protrude as long as the side surface of the conductive rubber 630 is suppressed.

  Further, the vehicle instrument 1 in the present embodiment has the pointer instrument 30 that is an analog instrument that rotates the pointer 31, but is mainly configured by a display element such as a liquid crystal display unit 40 that does not include the pointer instrument 30. It may be done.

1 Vehicle meters (display devices)
DESCRIPTION OF SYMBOLS 10 Upper case 11 Perspective cover member 110 Locking part 111 Elastic arm piece 112 Hook part 12 Partition member 120 Engaging part 121 Locking part 122 Elastic arm piece 123 Hook part 124 Shielding part 20 Lower case 210 Engaging part 220 Mount part 30 pointer instrument 31 pointer 32 movement 32a shaft 40 liquid crystal display unit (display means)
41 Display (display element)
42 Metal frame
50 Display board (protective member)
51 Translucent substrate 52 Impervious portion 53 Adhesive strength enhancement layer (adhesive strength enhancement portion)
60 wiring board 61 external connector 62 control unit 63 grounding means 630 conductive rubber 631 fixing unit 70 middle case

Claims (3)

Display means comprising a display element for displaying predetermined information;
A conductive frame covering the display means;
A wiring board disposed on the bottom side of the frame and having a ground connection;
A columnar conductive elastic body that electrically connects the bottom surface of the frame and the ground connection portion;
Engaging with the wiring board, covering substantially the entire circumference of the side surface of the conductive elastic body, and having a standing wall portion shorter than the conductive elastic body, the conductive elasticity against the displacement between the display means and the wiring board A display device comprising: a fixing portion that deformably holds a tip of the body on the display means side. Display means comprising a display element for displaying predetermined information;
A conductive frame covering the display means;
A wiring board disposed on the bottom side of the frame and having a ground connection;
A columnar conductive elastic body that electrically connects the bottom surface of the frame and the ground connection portion;
Displacement between the display means and the wiring board is disposed between the display means and the wiring board, covers substantially the entire circumference of the side surface of the conductive elastic body, and has a standing wall portion shorter than the conductive elastic body. A display device, comprising: a middle case that partially forms a fixing portion that holds the tip of the conductive elastic body on the display means side in a deformable manner. A plate-like display board joined to the display surface side of the display means ;
The display device according to claim 2, wherein the middle case holds the display board.

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