JP5156274B2 - Support member for LCD panel - Google Patents

Description

  The present invention relates to a liquid crystal panel support member that supports a liquid crystal panel in an explosion-proof liquid crystal display device used in a hazardous area.

  It is necessary to refer to information such as the state of the equipment when setting and inputting operating conditions for the equipment to be controlled in a hazardous area such as a flammable gas atmosphere. It is also necessary to confirm information such as the current settings of the device. In order to make an operator recognize such information, a display device in which a liquid crystal panel is housed in an explosion-proof container is used.

  In order to sufficiently reduce current consumption to ensure explosion-proof performance, it is necessary to use a small liquid crystal panel with a small screen. However, a small liquid crystal panel has a limited amount of information that can be displayed at one time, and cannot handle an application with a large amount of information to be displayed.

In view of this, there is one in which a large amount of information can be displayed even in a hazardous area by storing a large liquid crystal panel having a relatively large screen in a flameproof container (for example, see Patent Document 1). A liquid crystal panel is generally made of metal together with a substrate mounted with a backlight, a drive circuit for a backlight, etc. in a state in which a liquid crystal module is configured with a substrate mounted with a drive circuit and a control circuit for the liquid crystal panel. It is accommodated in the support member.
JP 2005-276045 A

  However, when the liquid crystal panel is housed in an explosion-proof container and used in a hazardous area, a predetermined creepage distance and a solid separation distance are given between each electrical component included in the liquid crystal module according to the explosion-proof structure standard. Is required. When a conductive metal material is used for the support member of the liquid crystal module panel, the substrate for the liquid crystal panel and the substrate for the backlight must be sufficiently separated, and the support member becomes large. In particular, when a large liquid crystal panel is used to display a large amount of information, the support member is further enlarged, and the explosion-proof container that needs to have a robust structure after storing the support member is also enlarged and heavy and expensive. become. Further, since the peripheral edge of the liquid crystal module and the backlight are arranged apart from each other, the amount of light emitted from the backlight is attenuated, and the screen of the liquid crystal panel becomes dark.

  An object of the present invention is to devise a structure for supporting a liquid crystal panel in a container, thereby realizing a reduction in size, weight, and cost of a container for storing a liquid crystal display, and an increase in screen brightness. The object is to provide a support member for a liquid crystal panel.

As a means for solving the above-mentioned problems, in the liquid crystal panel support member of the present invention, the liquid crystal module housing portion, the light guide plate housing portion, the backlight housing portion, and the partition are integrally formed of an insulating resin. The liquid crystal module storage unit opens to the front and stores the liquid crystal module. The liquid crystal module is configured by attaching a liquid crystal panel and at least a first substrate on which a drive circuit for the liquid crystal panel is mounted on a sheet metal. The light guide plate storage unit stores the light guide plate on the back side of the liquid crystal module storage unit. The backlight storage unit stores the backlight at a position facing one end surface of the light guide plate stored in the light guide plate storage unit. The partition wall is formed in parallel to the back surface of the backlight housing portion, and is located between the peripheral edge portion of the liquid crystal module housed in the liquid crystal module housing portion and the backlight housed in the backlight housing portion. The backlight is positioned between the back surface of the back and the backlight housing portion of the partition wall. The backlight storage unit is open to the outside along the surface direction of the light guide plate stored in the light guide plate storage unit, and a plurality of LEDs are mounted on the second substrate at regular intervals along one end surface. The light is inserted along the surface direction, and a locking piece that engages with one end of the backlight is elastically deformable along the insertion direction of the backlight. The sheet metal includes a claw that prevents elastic deformation of the locking piece.

In this configuration, since the partition wall made of an insulating resin is located between the peripheral edge of the liquid crystal module housed in the liquid crystal module housing section and the backlight housed in the backlight housing section, the liquid crystal module and the backlight Even when they are arranged close to each other, a predetermined creepage distance and a solid separation distance are secured between them. For this reason, it is preferable that a partition has a bending part. Moreover, the partition wall can be extended to a length that ensures a predetermined creepage distance and solid separation distance required for the explosion-proof structure between the liquid crystal module and the backlight.

In this configuration, it may abut the end of the septum wall on one end face of the light guide plate housing portion is housed in the light guide plate. The partition wall functions as a reflector of the backlight together with the back surface of the backlight housing portion, so that a sufficient amount of light can be introduced into the inside from one end surface of the light guide plate, and the brightness of the screen of the liquid crystal panel can be increased.

Furthermore, a control board storage section for storing a third board mounted with a control circuit of the liquid crystal panel in parallel with the liquid crystal panel may be provided on the back surface. When the liquid crystal module includes the third substrate on which the control circuit is mounted separately from the first substrate on which the drive circuit is mounted, the liquid crystal module can be formed in a small size .

  According to the present invention, the insulating resin partition located between the peripheral edge of the liquid crystal module housed in the liquid crystal module housing section and the backlight housed in the backlight housing section allows the liquid crystal module and the backlight to be separated from each other. A predetermined creepage distance and solid separation distance can be secured between them. The liquid crystal module and the backlight can be arranged close to each other after ensuring a predetermined creepage distance and solid separation distance required for the explosion-proof structure. As a result, it is possible to reduce the size, weight and cost of the container for storing the liquid crystal display, and to increase the brightness of the screen.

  FIG. 1 is an external view of an explosion-proof liquid crystal display device to which a liquid crystal panel support member according to an embodiment of the present invention is applied. As an example, the explosion-proof liquid crystal display device 10 is a teaching pendant used when setting control data in a device installed in a hazardous area.

  The explosion-proof liquid crystal display device 10 is configured by housing a liquid crystal display in a container 4 having an intrinsically safe explosion-proof structure. The liquid crystal display includes a liquid crystal panel, a drive circuit, a control circuit, and a case. The container 4 includes a main body 4A and a back cover 4B. The main body 4 includes a window portion 4C and a key switch 4D on the front surface. The entire surface of the window portion 4C is covered with a hard glass plate, and the liquid crystal panel 41 housed inside faces the inner surface of the hard glass plate. The member that covers the window 4C is not limited to a hard glass plate, and various materials such as a resin can be used as long as it is transparent and can protect the liquid crystal panel 41.

  The liquid crystal panel 41 displays information such as the operation state of the device and control contents based on the image data. The window 4C can be provided with a transparent touch panel instead of hard glass. In this case, the liquid crystal panel 41 displays an image of the key switch.

  2A to 2F are a front view, a right side view, a rear view, a front view of the main body, an S1-S1 enlarged sectional view, and an S2-S2 enlarged sectional view of the liquid crystal panel support member. .

  The liquid crystal panel support member 3 is a thin casing in which a liquid crystal module storage unit 31, a light guide plate storage unit 32, a backlight storage unit 33, and a control board storage unit 34 are integrally formed of an insulating resin material. The support member 3 is formed with a concave portion opened to the front surface, and the liquid crystal module housing portion 31 and the light guide plate housing portion 32 are successively formed in this concave portion in this order from the front side to the back side.

  The liquid crystal module storage unit 31 stores the liquid crystal module 1. In this embodiment, the liquid crystal module 1 is configured by attaching a liquid crystal panel 41 and a drive substrate 42 to a sheet metal 43. A drive circuit that drives the liquid crystal panel 41 based on drive data is mounted on the drive substrate 42. The sheet metal 43 is a frame formed by press working using a metal plate as a material.

  The light guide plate storage portion 32 is located on the back side of the liquid crystal module storage portion 31 and stores the light guide plate 5. The light guide plate 5 diffuses and reflects the light incident from the end face and irradiates it with uniform brightness from the front.

  The backlight storage unit 33 is located above and below the light guide plate storage unit 32 and stores the backlight 6. In this embodiment, the backlight 6 is configured, for example, by mounting 18 LEDs 61 on the substrate 62 in a line at equal intervals. The substrate 62 is the second substrate of the present invention. The backlight storage unit 33 stores the backlight 6 in a state where the arrangement direction of the plurality of LEDs 61 faces along the upper end surface and the lower end surface of the light guide plate 5 stored in the light guide plate storage unit 32. The backlight storage portion 33 is open to the outside from the upper and lower end surfaces of the support member 3. The backlight 6 is inserted into the backlight storage portion 33 from the upper and lower end surfaces of the support member 3.

  The control board storage portion 34 is formed on the back surface of the support member 3 and stores the control board 11 in parallel with the liquid crystal panel 41. The control board storage portion 34 is formed with two locking pieces 34A and two screw holes 34B. After the upper end of the control board 11 is engaged with the locking surface 34A, the control board 11 is fixed by screwing a mounting screw 34C into the screw hole 34B.

  In this embodiment, a control circuit that supplies drive data for the liquid crystal panel 41 to the drive circuit based on the image data is mounted on the control board 11 that is different from the drive board 42. The control board 11 is connected to the drive board 12 by a flexible printed board. By arranging the control circuit in parallel with the back surface of the liquid crystal panel 41, the liquid crystal module 1 can be formed in a small size.

  It is not always necessary to form the control board storage portion 34 on the back surface of the support member 3. Further, when the control circuit is mounted on the drive board 42 together with the drive circuit, the control board storage portion 34 can be omitted.

  The liquid crystal module storage unit 31 is formed wider at least in the vertical direction than the light guide plate storage unit 32, and the upper and lower end portions overlap with a part of the backlight storage unit 33 in the vertical direction. The drive substrate 42 and the sheet metal 43 of the liquid crystal module 1 are located in the region overlapping the backlight storage portion 33 at the upper and lower ends of the liquid crystal module storage portion 31.

  The partition wall 7 is located in this region. The partition wall 7 is formed integrally with the support member 3 so as to extend from the inner side surface of the peripheral portion of the support member 3. On the front side of the partition wall 7, a portion of the end portion of the sheet metal 43 of the liquid crystal module 1 housed in the liquid crystal module housing portion 31 is exposed outside the end portion of the substrate 42. On the back side of the partition wall 7, the backlight 6 housed in the backlight housing portion 33 is located.

  As shown in FIG. 2F, the insulating partition 7 is located between the exposed portion of the sheet metal 43 and the substrate 62 of the backlight 6. As a result, even when the backlight 6 is disposed close to the liquid crystal panel 1 and the light guide plate 5, a predetermined creepage distance and a solid separation distance can be secured between the substrate 62 and the sheet metal 43, and the support member 3 is interposed. The liquid crystal panel 41 can be applied to the explosion-proof liquid crystal display device 10.

  A part of the end surface of the partition wall 7 is close to one end surface of the light guide plate 5. For this reason, substantially all of the light emitted from the LED 61 enters the inside from one end surface of the light guide plate 5 with the back surface of the partition wall 7 and the front surface side of the back surface of the support member 3 as reflectors, and liquid crystal is emitted from the front surface of the light guide plate 5. The panel 1 is irradiated with a sufficient amount of light. An image with sufficient brightness can be displayed on the liquid crystal panel 1.

  As shown in FIG. 2D, the partition wall 7 is formed with a slit 71 in a part along the one end surface of the light guide plate 5 in order to remove the mold of the support member 3 during resin molding. As shown in FIG. 2E, a sufficient creepage distance is formed between the substrate 62 and the sheet metal 43 by the bent portion of the partition wall 7 even in the portion where the slit 71 is formed.

  The slit 71 is located in the gap between two adjacent LEDs 61 in the direction along one end surface of the light guide plate 5. For this reason, the function of the partition wall 7 as a reflector is not significantly lowered by the slit 71.

  3A to 3C are diagrams showing an assembly operation of a liquid crystal display to which the liquid crystal panel support member is applied. First, the light guide plate 5 is inserted into the light guide plate storage portion 32 from the front side of the support member 3. The light guide plate 5 is attached to the back surface of the support member 3 via the double-sided tape 51 (see FIG. 3A).

  Next, the backlight 6 is inserted from the upper and lower end surfaces of the support member 3 into the backlight storage portion 33 positioned above and below the light guide plate storage portion 32. At this time, the conductive wire 64 previously extended from both ends of the backlight 6 is inserted into the hole 36 formed through the back surface of the support member 3 (see FIG. 3B).

  Finally, the liquid crystal module 1 is inserted into the support member housing portion 31 from the front side of the support member 3, and the set screw 11 is passed through the hole portion of the sheet metal 43 and then screwed into the screw hole 38 of the support member 3 (see FIG. 3 (C).) Thereby, the liquid crystal module 1, the light guide plate 5, and the backlight 6 are fixed in a state of being accommodated in the support 3.

  The backlight 6 is maintained in the backlight storage portion 33 by the elastic force of the locking piece 33A. Elastic deformation of the locking piece 33 </ b> A is prevented by the claw 43 </ b> A of the sheet metal 43. For this reason, after the sheet metal 43 is fixed to the support member 3, the backlight 6 does not come off from the backlight housing portion 33.

  The above embodiments are merely examples, and the present invention is not limited to these embodiments, and various modifications can be made within the scope of the present invention.

1 is an external view of an explosion-proof liquid crystal display device to which a liquid crystal panel support member according to an embodiment of the present invention is applied. FIG. 4 is a front view, a right side view and a rear view of the liquid crystal panel support member, a front view of the main body, an S1-S1 enlarged sectional view, and an S2-S2 enlarged sectional view. It is a figure which shows the assembly operation | work of the liquid crystal display to which the said supporting member for liquid crystal panels is applied.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Liquid crystal module 3 Support member 4 Container 5 Light guide plate 6 Backlight 11 Control board (3rd board | substrate)
31 Liquid Crystal Module Storage Unit 32 Light Guide Plate Storage Unit 33 Backlight Storage Unit 41 Liquid Crystal Panel 42 Driving Substrate (First Substrate)
43 Sheet metal

Claims (5)

A liquid crystal module housing portion opened to the front, wherein the liquid crystal module housing portion accommodates a liquid crystal module configured by attaching a liquid crystal panel and at least a first substrate mounted with a driving circuit of the liquid crystal panel on a sheet metal;
A light guide plate storage portion for storing a light guide plate on the back side of the liquid crystal module storage portion;
A backlight storage unit that stores a backlight at a position facing one end surface of the light guide plate stored in the light guide plate storage unit;
A partition located between a peripheral edge of the liquid crystal module housed in the liquid crystal module housing section and a backlight housed in the backlight housing section;
Is formed integrally with insulating resin,
The partition is formed in parallel to the back surface of the backlight storage unit,
The backlight is positioned between the rear and the rear face of the backlight housing portion of the partition wall,
The backlight storage unit is opened to the outside along the surface direction of the light guide plate stored in the light guide plate storage unit, and a plurality of LEDs are arranged on the second substrate at regular intervals along the one end surface. The mounted backlight is inserted along the surface direction, and a locking piece that engages with one end of the backlight is elastically deformable along the insertion direction of the backlight,
The sheet metal is a support member for a liquid crystal panel provided with a claw for preventing elastic deformation of the locking piece .   The liquid crystal panel support member according to claim 1, wherein the partition wall has a bent portion.   3. The support member for a liquid crystal panel according to claim 1, wherein an end of the partition abuts on the one end surface of the light guide plate stored in the light guide plate storage. The support member for a liquid crystal panel according to any one of claims 1 to 3 , further comprising a control substrate storage portion that stores a third substrate mounted with a control circuit for the liquid crystal panel in parallel with the liquid crystal panel. . The partition wall, the liquid crystal according to any of claims 1 to 4 extending in the length to secure a predetermined creepage distance and solid separation required for explosion-proof between the liquid crystal module and the backlight Panel support member.

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