JP6691577B2 - Lighting device and liquid crystal display device - Google Patents

Description

  The present invention relates to an illuminating device that irradiates light emitted from a light source disposed opposite to a side surface of a light guide plate through the light guide plate, and a liquid crystal display device including the illuminator.

  As an illumination device mounted on a liquid crystal display device, there is an edge light type illumination device. In the edge light type lighting device, a light guide plate is arranged so as to overlap with a liquid crystal panel, and one or more light sources are arranged so as to face a side surface located at an edge portion of the light guide plate. The light emitted from the light source is scattered by the light guide plate, so that the brightness of the liquid crystal panel as the irradiation target is made uniform.

  One of the problems of the liquid crystal display device is that the light source is not turned on and the brightness is reduced due to the life of the light source. Since such a defect can be repaired by replacing the light source, a lighting device having a replaceable light source has been proposed (for example, refer to Patent Document 1). In this conventional lighting device, the light source is configured to be inserted into and removed from the housing, and the spacer is provided to secure the distance between the side surface of the light guide plate and the light source, so that the light source is slid into the housing. It is intended to prevent damage to the light source due to interference between the light guide plate and the light guide plate.

  When a point light source such as an LED (Light Emitting Diode) is used as a light source, the light of the light source is incident on the light guide plate as little as possible in order to maximize the use of the light of the light source as the backlight of the liquid crystal display device. This is very important. Therefore, not only is the distance between the incident surface of the light guide plate, that is, the side surface, and the light source set to a predetermined value, but also the light source is held at a predetermined position with respect to the side surface of the light guide plate in the longitudinal direction of the side surface of the light guide plate. is important.

JP, 2009-224301, A

  However, the conventional illumination device does not consider holding the light source at a predetermined position with respect to the side surface of the light guide plate in the longitudinal direction of the side surface of the light guide plate. Therefore, in the conventional lighting device, although the light source can be replaced, the light source may not be held at a predetermined position in the longitudinal direction of the side surface of the light guide plate. Therefore, the brightness may decrease.

  An object of the present invention is to provide an illuminating device capable of exchanging light sources and suppressing a decrease in brightness, and a liquid crystal display device including the illuminating device.

  The lighting device according to the present invention includes a light guide plate, a support plate, and a light source holding member. The support plate is arranged at a position overlapping the light guide plate. The support plate has a rising portion that rises from the edge portion toward the light guide plate side and is continuously formed along the edge portion. The light source holding member has a leaf spring portion that extends in the longitudinal direction of the rising portion, holds the light source so as to face the light guide plate, and projects toward the rising portion side.

  According to the above lighting device, when a defect occurs in the light source, the light source holding member is detached from the rising portion, and the replacement light source holding member is attached to the rising portion to repair the light source defect. You can The light source holding member is fixed to the rising portion by the leaf spring portion of the light source holding member pressing the rising portion. As a result, the light source is arranged to face the light guide plate at a predetermined position.

  In the above lighting device, it is preferable that the rising portion has a concave portion that is pressed by the leaf spring portion.

  According to this configuration, the leaf spring portion of the light source holding member presses the concave portion of the rising portion, so that the light source holding member is positioned in the longitudinal direction with respect to the rising portion. As a result, the light source is arranged to face the light guide plate at a predetermined position.

  In the above lighting device, it is preferable that the light source holding member is detachable over the entire length of the rising portion and slidable in the longitudinal direction of the rising portion.

  With this configuration, the light source can be easily replaced. Therefore, the convenience of the user can be improved.

  In the above lighting device, the support plate has a groove along the inner surface of the rising portion, and when the light source holding member is mounted on the rising portion, the end portion in the longitudinal direction of the light source holding member is arranged in the groove. It is preferable.

  With this configuration, the light source holding member is less likely to be displaced from the support plate. In particular, the positional deviation of the rising portion in the rising direction is surely suppressed. Therefore, the light source holding member can be continuously held on the support plate.

  In the above illumination device, it is preferable that the light source is a point light source and is held by a light source holding member in a direction facing the side surface of the light guide plate.

  With this configuration, the light from the light source can be used to the maximum extent.

  A liquid crystal display device of the present invention includes any one of the lighting devices described above.

  With this configuration, when a defect occurs in the light source, the defect can be repaired by replacing the light source holding member.

  According to the present invention, it is possible to replace the light source and suppress a decrease in brightness.

FIG. 1 is an exploded perspective view from the rear right showing a schematic configuration of a liquid crystal display device including the lighting device according to the first embodiment of the present invention. It is a front view which shows schematic structure of some members of a liquid crystal display device. (A) is a perspective view of a part of a light source holding member, (B) is a side view of a light source holding member, (C) is a perspective view of a part of a heat sink, (D) is a heat sink. It is a side view of a part of. (A) is a side view of a part of a heat sink and a light source holding member, and (B) is an enlarged view of a part of the view shown in (A). (A) is a front view of a part of the light source holding member attached to the rising portion of the heat dissipation plate, (B) is a bottom view thereof, and (C) is a part of the diagram shown in (B). FIG. It is an enlarged view of a part of heat dissipation plate and a light source holding member of an illuminating device concerning a 2nd embodiment.

  As shown in FIG. 1, an illuminating device 10 according to the first embodiment of the present invention is an edge light type and is mounted on a liquid crystal display device 100 as a backlight. The liquid crystal display device 100 includes a front frame 101, a liquid crystal panel 102, optical sheets 103, 104 and 105, a lighting device 10, a chassis 106, a reinforcing angle 107, and a rear cabinet 108, and these members overlap each other in this order. It is located in a position.

  The illumination device 10 includes a light guide plate 20, a reflection sheet 30, a P frame 40, a heat dissipation plate 50, and a light source holding member 60.

  As shown in FIG. 2, the P frame 40 has a rectangular frame shape. The light guide plate 20 is positioned at a predetermined position inside the P frame 40 and is supported by the P frame 40. The heat dissipation plate 50 has a rectangular shape when viewed from the front and is supported by the P frame 40. The light source holding member 60 is supported on each of an upper end portion and a lower end portion of the heat dissipation plate 50. The heat dissipation plate 50 is a support plate that supports the light source holding member 60.

  The light source holding member 60 holds a plurality of light sources 61 arranged in a line. A point light source is used as the light source 61. As an example, the point light source is an LED (Light Emitting Diode). The light source 61 faces the incident surface of the light guide plate 20, that is, each of the upper and lower side surfaces.

  As shown in FIG. 1, FIG. 3 (C) and FIG. 3 (D), the heat dissipation plate 50 has a main surface portion 51 and two rising portions 52. The rising portion 52 rises in a direction orthogonal to the main surface portion 51 and closer to the light guide plate 20 from each edge of the main surface portion 51 in the vertical direction, that is, the upper side and the lower side of the main surface portion 51 in the first direction 91. It faces the upper and lower side surfaces 21 of the light plate 20.

  The rising portion 52 has a recess 53 at least at one position in the longitudinal direction of the side surface 21 of the light guide plate 20, that is, in the second direction 92. As an example, the recesses 53 are provided at two different positions in the second direction 92. In addition, as an example, the recessed portion 53 is provided on a side surface orthogonal to the rising direction of the rising portion 52, that is, the third direction 93. The first direction 91, the second direction 92, and the third direction 93 are orthogonal to each other.

  In addition, the rising portion 52 has a groove 54 that extends in the second direction 92 on at least one of the inner side surface and the outer side surface in the first direction 91. In this embodiment, the recessed portion 54 is provided on the outer side surface in the first direction 91.

  Further, the main surface portion 51 of the heat dissipation plate 50 has a groove portion 55 along the inner side surface of the rising portion 52 in the first direction 91.

  The rising portion 52 has a substantially uniform rectangular cross section in the second direction 92 except for the recess 53.

  As shown in FIG. 3A, FIG. 3B, FIG. 4A and FIG. 4B, the light source holding member 60 has a substrate holding member 62 and a light source substrate 63. The substrate holding member 62 has three surfaces 64, 65, 66 forming a U-shaped cross section, and at least the two surfaces 64, 65 facing each other out of the three surfaces 64, 65, 66. It has a ridge 67 on one side. In this embodiment, the protruding portion 67 is provided on the outer surface 65 in the first direction 91, that is, the surface 65 facing the recessed portion 54 of the rising portion 52. The protruding portion 67 extends in the second direction 92 and projects toward the rising portion 52 side. In this embodiment, the substrate holding member 62 is made of metal.

  As described above, since the two surfaces 64 and 65 facing each other have the elastic force in the direction of approaching each other, the light source holding member 60 sandwiches the rising portion 52 by the elastic force, and the light source holding member 60 and the rising portion 52 are The frictional force between them makes it difficult for the light source holding member 60 and the rising portion 52 to be displaced. Further, since the ridge 67 is provided on at least one of the two surfaces 64 and 65 facing each other, the unintended release of the engagement between the ridge 67 and the recess 54 is suppressed. Therefore, the positional deviation of the light source holding member 60 with respect to the rising portion 52 in the rising direction of the rising portion 52 is more reliably suppressed.

  The substrate holding member 62 slides the substrate holding member 62 in the second direction 92 with respect to the rising portion 52 while engaging the protruding portion 67 and the recessed portion 54, so that the substrate holding member 62 with respect to the rising portion 52. It can be attached and detached.

  The light source holding member 60 is accurately positioned in the third direction 93 with respect to the rising portion 52 by engaging the protruding portion 67 with the recessed portion 54.

  When the substrate holding member 62 is mounted on the rising portion 52, one end of the surface 64 of the substrate holding member 62 in the third direction 93 is arranged in the groove 55.

  The substrate holding member 62 is provided on the inner surface 64 in the first direction 91 of the two surfaces 64 and 65 facing each other, that is, on the surface 64 facing the side surface 21 of the light guide plate 20 when mounted on the rising portion 52. The light source board 63 is held.

  The light source substrate 63 holds a plurality of light sources 61 on the plate portion in a line in the second direction 92. As an example, the plate portion of the light source substrate 63 is formed of a material having high thermal conductivity. The light source substrate 63 is held by the substrate holding member 62 by the caulking portion 68. The crimp portion 68 is provided at a plurality of locations in the second direction 92. In the caulking portion 68, a cylindrical protrusion protruding from the substrate holding member 62 is passed through a hole provided in the plate portion, and the tip end portion of the protrusion is deformed by applying pressure, so that the tip end portion of the protrusion is plate-shaped. It is crimped to the department.

  As shown in FIG. 3A, FIG. 3B, FIG. 5A, FIG. 5B, and FIG. 5C, the substrate holding member 62 has a plate spring portion 69 on the surface 66. is doing. The leaf springs 69 are preferably provided in the same number as the recesses 53. In this embodiment, two leaf spring portions 69 are provided. The leaf spring portion 69 is provided at a position facing the recess 53 when the substrate holding member 62 is mounted on the rising portion 52.

  The leaf spring portion 69 is formed in a notch portion of the surface 66 in a tongue shape extending from one side to the other side in the second direction 92.

  The leaf spring portion 69 is bent in the second direction 92, and has a bent portion 691 and two inclined surfaces 692 and 693 that form the bent portion 691. The two inclined surfaces 692 and 693 are located on the opposite sides of the bent portion 691 in the second direction 92. The bent portion 691 projects toward the rising portion 52 side when the substrate holding member 62 is mounted on the rising portion 52. The leaf spring portion 69 presses the concave portion 53 of the rising portion 52.

  When the light source 61 has a defect, the light source holding member 60 is detached from the rising portion 52, and the replacement light source holding member 60 is attached to the rising portion 52, whereby the defect of the light source 61 can be repaired. it can. The light source holding member 60 is mounted by sliding on the rising portion 52 of the heat dissipation plate 50. When the light source holding member 60 is slid with respect to the rising portion 52, the leaf spring portion 69 of the light source holding member 60 reaches the concave portion 53 of the rising portion 52 and the leaf spring portion 69 presses the concave portion 53, The light source holding member 60 is positioned in the second direction 92 with respect to the rising portion 52. As a result, the light source 61 is arranged to face the side surface 21 of the light guide plate 20 at a predetermined position. Therefore, the light source 61 can be replaced, and a decrease in brightness can be suppressed.

  Further, since the light source holding member 60 is supported by the heat dissipation plate 50, the heat emitted from the light source 61 is conducted through the heat dissipation plate 50 and is radiated to the outside. Therefore, thermal deformation of members such as the optical sheets 103, 104, 105, the light guide plate 20, and the reflection sheet 30 is suppressed. In addition, the load of the light source 61 due to heat is reduced, and a decrease in the efficiency of converting electricity into light is suppressed.

  It is preferable that the two leaf spring portions 69 are formed so as to extend in mutually opposite directions in the second direction 92. In both of the two leaf springs 69, the inclined surface 692 on the base end side in the second direction 92 is configured to press the upper edge 531 of one recess side surface of the recess 53 in the second direction 92. As a result, the inclined surfaces 692 of the two leaf spring portions 69 press the upper edge portions 531 of the concave portions 53 in mutually opposite directions, so that the light source holding member 60 moves toward the rising portion 52 in the second direction 92. Is positioned more accurately at. In addition, it is preferable that the bent portion 691 does not come into contact with the bottom surface of the recess 53 when the inclined surface 692 presses the upper edge portion 531 of the recess side surface.

  Next, the illumination device 10 according to the second embodiment will be described.

  As shown in FIG. 6, the recess 53 of the rising portion 52 has a bottom surface 532 and recess side surfaces 533 and 534 rising from the bottom surface 532. In the illumination device 10 according to the second embodiment, the two inclined surfaces 692 and 693 of the bent portion 691 are in the second direction 92 when the bent portion 691 of the leaf spring portion 69 does not contact the bottom surface 532 of the recess 53. The illumination device 10 has the same configuration as that of the illumination device 10 according to the first embodiment, except that the illumination device 10 is configured to contact the upper edge portions 535 and 536 of the recess side surfaces 533 and 534 facing each other.

  The movement of the light source holding member 60 with respect to the rising portion 52 is restricted in the direction in which the inclined surface 692 presses the upper edge portion 535 of the recess side surface 533 and the direction in which the inclined surface 693 presses the upper edge portion 536 of the recess side surface 534. . That is, the movement of the light source holding member 60 with respect to the rising portions 52 in both directions along the second direction 92 is restricted. Therefore, the two inclined surfaces 692 and 693 press against the upper edge portions 535 and 536 of the recess side surfaces 533 and 534, respectively, so that the light source holding member 60 moves in both directions along the second direction 92 with respect to the rising portion 52. In, the positioning is more accurate.

  Next, the lighting device 10 according to the third embodiment will be described.

  The illumination device 10 according to the third embodiment is similar to the illumination device 10 according to the first embodiment except that the substrate holding member 62 has an elastic force in a direction in which two surfaces 64, 65 facing each other approach each other. It is similarly configured.

  Since the substrate holding member 62 has an elastic force in a direction in which the two surfaces 64 and 65 facing each other approach each other, the substrate holding member 62 holds the rising portion 52 by the elastic force, and the substrate holding member 62 holds the rising portion 52. The holding force makes it difficult for the substrate holding member 62 and the rising portion 52 to be displaced. Further, since the ridge 67 is provided on at least one of the two surfaces 64, 65 facing each other, the unintended release of the engagement between the ridge 67 and the concave ridge 54 is suppressed. Therefore, the positional deviation of the substrate holding member 62 with respect to the rising portion 52 in the third direction 93 is more reliably suppressed.

  It should be noted that the substrate holding member 62 can be configured to be attachable to and detachable from the rising portion 52 in the direction along the third direction 93.

  It is possible to construct a new embodiment by combining the technical features of the above-described embodiments with each other.

  The description of the above embodiments is to be considered as illustrative in all points and not restrictive. The scope of the invention is indicated by the claims rather than the embodiments described above. Further, the scope of the present invention is intended to include meanings equivalent to the claims and all modifications within the scope.

10 Lighting device 20 Light guide plate 50 Radiating plate (support plate)
52 rising part 53 concave part 54 concave line part 60 light source holding member 61 light source 62 substrate holding member 64, 65, 66 surface 67 ridge part 69 leaf spring part 691 bent part 692, 693 inclined surface 100 liquid crystal display device

Claims (5)

A light guide plate,
A main surface portion arranged at a position overlapping with the light guide plate, and continuously formed along the upper edge portion and the lower edge portion rising from the upper edge portion and the lower edge portion of the main surface portion to the light guide plate side. a support plate having a rising portion which is,
A light source holding member that extends in the longitudinal direction of the rising portion and holds the light source so as to face the light guide plate;
Equipped with
The support plate has a groove portion along an inner surface of the rising portion, and when the light source holding member is mounted on the rising portion, an end portion in the longitudinal direction of the light source holding member is arranged in the groove portion. Lighting equipment. The light source holding member has a leaf spring portion protruding toward the rising portion side,
The lighting device according to claim 1, wherein the rising portion has a concave portion that is pressed by the leaf spring portion.   The lighting device according to claim 1 or 2, wherein the light source holding member is configured to be detachable over the entire length of the rising portion and slidable in the longitudinal direction of the rising portion.   The illumination device according to claim 1, wherein the light source is a point light source, and is held by the light source holding member in a direction facing a side surface of the light guide plate. A liquid crystal display device comprising the lighting device according to claim 1.

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