JP5353788B2 - Dust-proof structure of planar light source - Google Patents

Description

  The present invention relates to an improvement in a dustproof structure of a planar light source.

In a surface illumination, for example, a liquid crystal display device having a light emitting surface as a display surface, it is fatal that a foreign substance enters the device. This is because foreign matter appears on the display surface and the design is impaired, and the display content to be displayed on the display surface may not be visible due to the foreign matter.
In particular, a small liquid crystal display device of about several inches often adopts a configuration in which a liquid crystal panel and other planar optical components are accommodated in a pair of resin frames. In such a configuration, a gap may be generated between the mating surface of the frame and the planar optical component due to manufacturing variations or thermal expansion.
For this reason, Patent Documents 1 and 2 describe a technique in which a gap between a frame and a planar optical component is sealed with a rib or tape in order to prevent foreign matter from entering from the outside.
Reference should be made to Patent Document 3 for disclosing a technique related to the present invention.

JP 05-66405 A JP 2009-186831 A JP 2004-361654 A

The dust-proof rib is provided on the frame side, but the arrangement position is limited in order not to disturb the function of the planar optical component housed in the frame. Moreover, the request | requirement of size reduction and thickness reduction of a planar light source may be restrict | limited by a rib.
Use of a seal is not preferable because it leads to an increase in the number of parts and an increase in assembly cost.
Accordingly, an object of the present invention is to provide a dustproof structure suitable for miniaturization of a planar light source without particularly increasing the number of components.

The present invention has been made to achieve the above object. That is, the first aspect of the present invention is defined as follows.
A dust-proof structure of a planar light source that stores and holds a planar optical component in a first frame and a second frame,
By engaging the engaging portion formed on the outer wall of the first frame and the engaged portion formed on the outer wall of the second frame, the first frame and the second frame are Concatenated,
An auxiliary wall along the outer wall is formed on the first frame, the top of the auxiliary wall abuts on the inner peripheral surface of the second frame, and a foreign substance trap groove is formed between the outer wall and the auxiliary wall. A dust-proof structure for a planar light source, characterized in that

According to the dust-proof structure of the planar light source of the first aspect thus defined, the foreign matter trapping groove is constituted by the outer wall of the frame and the auxiliary wall along the outer wall, and the auxiliary wall extends along the outer wall. Since it is provided, it hardly interferes with the contents of the frame. In other words, the design freedom of the planar light source is not impaired by providing the auxiliary wall. This meets the demand for downsizing or thinning the planar light source.
Furthermore, since the auxiliary wall can be formed integrally with the frame, the number of parts does not increase.

The second aspect of the present invention is defined as follows. That is, in the dust-proof structure of the planar light source defined in the first aspect, a connector opening is formed in the second frame, the connector opening is closed by the LED board, and the first surface of the LED board is Is provided with a connector exposed through the connector opening,
The top of the second auxiliary wall formed on the second frame and the planar optical component are pressed to the periphery of the second surface of the LED substrate,
A support member that contacts the second surface of the LED substrate so as to face the connector is formed on the second frame, and prevents the LED substrate from shifting or deforming to the second surface side.
According to the dustproof structure of the planar light source of the second aspect defined in this way, by pressing the second auxiliary wall and the planar optical component formed on the second frame against the periphery of the LED substrate. Dust protection is provided between the connector opening and the LED substrate covering the opening, but a support member is further formed on the second frame, and this support member prevents the LED substrate from shifting or deforming. Thus, the sealing performance between the LED substrate and the peripheral edge of the opening becomes stronger.

In the above, it is preferable that the auxiliary wall is formed continuously with respect to the outer wall (see the fourth aspect). As a result, the foreign matter trapped in the foreign matter trapping groove does not leak out. When the planar optical component has a claw, it is preferable to provide a groove for accommodating the claw in the auxiliary wall (see the fifth aspect).
The support member for preventing deformation of the LED substrate has a wall structure similar to the auxiliary wall, and by forming the auxiliary wall in parallel with the auxiliary wall, a second trap groove is formed between the support member and the auxiliary wall, Foreign matter can also be shut out in the second trap groove.

The sixth aspect of the present invention is defined as follows. That is,
A dust-proof structure of a planar light source that stores and holds a planar optical component in a first frame and a second frame,
By engaging the engaging portion formed on the outer wall of the first frame and the engaged portion formed on the outer wall of the second frame, the first frame and the second frame are Concatenated,
A connector opening is formed in the first frame, the connector opening is closed with an LED board, and a connector exposed through the connector opening is provided on the first surface of the LED board,
The top portion of the second auxiliary wall formed on the second frame and the planar optical component are pressed to the peripheral portion of the second surface of the LED substrate,
A support member that contacts the second surface of the LED substrate so as to face the connector is formed on the second frame, and prevents the LED substrate from shifting or deforming to the second surface side. A dustproof device for a planar light source.
According to the dustproof device for a planar light source of the sixth aspect defined in this way, the second auxiliary wall and the planar optical component formed on the second frame, as in the invention of the second aspect, Is pressed against the periphery of the LED board to take dust prevention between the connector opening and the LED board covering the opening, but a support member is further formed on the second frame, and this support member This prevents the LED substrate from being shifted or deformed, so that the sealing performance between the LED substrate and the peripheral edge of the opening becomes stronger.

FIG. 1 shows a planar light source according to an embodiment of the present invention, in which (A) is a perspective view of an upper frame (second frame), and (B) is a perspective view of a lower frame (first frame). . FIG. 2 is a cross-sectional view at the II-II position (see FIG. 2) when the upper frame and the lower frame are assembled. FIG. 3 is a partially enlarged perspective view showing another form of auxiliary wall. FIG. 4 is a cross-sectional view at the IV-IV position (see FIG. 2) when the upper frame and the lower frame are assembled.

Hereinafter, the planar light source 1 according to the embodiment of the present invention will be described.
The planar light source 1 according to the embodiment includes a resin frame part 3, a planar optical component 40, and an LED light source unit 50.
The frame unit 3 includes a lower frame 10 (first frame (see FIG. 1B)) and an upper frame 20 (second frame (see FIG. 1A)).
The first frame 10 includes a rectangular flat plate-shaped base portion 11 and an outer wall 12 formed by bending the peripheral portion thereof. An engaging claw (engaging portion) 13 is formed on the outer surface of the outer wall 12. The formation position and number of the engaging claws 13 are not particularly limited, and are appropriately selected according to the purpose of use of the planar light source 1.
A first auxiliary wall 15 is formed integrally with the base body 11 along the outer wall 12 inside the outer wall 12. In this example, the first auxiliary wall 15 is formed on the pair of opposed outer walls 12 and 12, but the first auxiliary wall 15 may be formed on the entire circumference.
A groove 16 is formed in the first auxiliary wall 15. The claw of the planar optical component 40 is fitted into the groove 16 so that the planar optical component 40 is positioned and prevented from being displaced.

The second frame 20 includes a rectangular frame body 21 and an outer wall 22 formed on the outer peripheral edge thereof. An engagement hole 23 is formed in a portion of the outer wall 22 that extends downward, and the engagement claw 13 of the first frame 10 is engaged with the periphery of the engagement hole 23. Reference numeral 24 denotes an opening, through which the planar optical component is exposed and emits light.
A second auxiliary wall 26 and a support member 28 are erected integrally on the back surface of the second frame 20.

  An engagement structure between the first frame 10 and the second frame 20 is shown in FIG. As shown in FIG. 3, the engagement claw 13 formed on the outer wall 12 of the first frame 10 and the peripheral edge of the engagement hole 23 formed on the outer wall 22 of the second frame 20 are engaged with each other. The frame 10 and the second frame 20 are combined. At this time, since both the frames 10 and 20 are made of resin, the outer walls 12 and 22 are flexibly deformed, and the engagement between the engagement claw 13 and the periphery of the engagement hole 23 is clipped.

The top portion of the first auxiliary wall 15 provided along the outer wall 12 in the first frame 10 is applied to the inner peripheral surface of the frame body 21 of the second frame 20. Thereby, a sealing property is provided between the first auxiliary wall 15 and the frame body 21 of the second frame 20, so that foreign matters that have passed through between the outer wall 12 and the outer wall 22 can be shut out here. In other words, the trap groove 18 is formed between the outer wall 12 and the first auxiliary wall 15, and foreign matter from outside is trapped by the trap groove 18 so as not to enter the frame portion 10.
In order to trap the foreign matter trapped in the trap groove 18, it is preferable that the outer wall 12 and the first auxiliary wall 15 constituting the trap groove 18 are continuous without a gap so that the trap groove 18 is a closed space. In particular, when the groove 16 is provided, it is preferable to block the groove 16 and the trap groove 18 (see FIG. 3).

FIG. 4 is a partial enlarged cross-sectional view showing the configuration of the connector portion.
A connector opening 30 is formed in the first frame 10.
Reference numeral 40 denotes a planar optical component, and the planar optical component 40 includes general components such as a reflection sheet 41, a light guide plate 43, and a diffusion sheet 45. Each component of the planar optical component 40 has a claw, and the claw is fitted into the groove 16 formed in the first auxiliary wall 15 so as to stabilize the position.
The planar optical component 40 is sandwiched between the first frame 10 and the second frame 20.

Reference numeral 50 denotes an LED light source unit, which includes an LED light source 51, a power supply circuit component 53, an LED substrate 55, and a connector 57. In this example, a white light emitting LED is used as the LED light source 51, but the light emission color can be arbitrarily selected. The power supply circuit component 53 includes a resistor and a capacitor. The LED light source 51 and the power circuit component 53 are coupled to the second surface (upper surface in the drawing) of the LED substrate 55, and the connector 57 is connected to the first surface (lower surface in the diagram) of the LED substrate 55. Is done.
The LED board 55 is made of resin and is larger than the connector opening 30 and covers the connector opening 30. One peripheral portion of the second surface (upper surface in the drawing) of the LED substrate 55 is pressed by a second auxiliary wall 26 protruding from the second frame 20. The second auxiliary wall 26 is formed along the outer wall 22 and extends along the peripheral edge of the connector opening 30. The edge of the planar optical component 40 is pressed to the other peripheral portion of the second surface of the LED substrate 55. In this way, the LED board 55 is pressed against the peripheral edge of the connector opening 30 to prevent foreign matter from entering from the connector opening 30.

  A support member 28 is formed on the second frame 20 and abuts against the second surface of the LED substrate 55. The support member 28 is disposed to face the connector 57. Thus, when the connector 57 is connected to the mating member, the LED board 55 remains in the same direction even when a force is applied from the mating member in the upward direction indicated by the arrow in FIG. 4 (the second surface side direction of the LED board 55). Will not shift or deform. If the LED substrate 55 is shifted or deformed upward, the sealing performance of the connector opening 30 by the LED substrate 55 is lowered, which is not preferable.

In comparison with FIG. 2, a foreign matter trap groove 68 is formed by the outer wall 22 (and the outer wall 12 of the first frame 10) and the second auxiliary wall 26. Further, since the support member 28 is also in contact with the second surface of the LED substrate 55, a second trap groove 69 is formed by the support member 28 and the second auxiliary wall 26. Thereby, the foreign material which slips through between the 1st frame part 10 and the 2nd frame part 20 can be trapped more reliably.
In the example of FIG. 4, the power supply circuit component 53 is disposed in the second trap groove 69. Thereby, since the support member 28 is interposed between the LED light source 51 and the power supply circuit component 53, the thermal influence from the LED light source 51 on the power supply circuit component 53 can be reduced.
From the viewpoint of constituting the second trap groove 69, the support member 28 is preferably formed along the second auxiliary wall 26 continuously.

The present invention is not limited to the description of the embodiments and examples of the invention described above. Various modifications may be included in the present invention as long as those skilled in the art can easily conceive without departing from the description of the scope of claims.
For example, in the above example, the first auxiliary wall 15 may be provided on the second frame 20 side.

DESCRIPTION OF SYMBOLS 1 Planar light source 10 1st flame | frame 12,22 Outer wall 13,23 Engagement part, to-be-engaged part 15,26 Auxiliary wall 18,68,69 Foreign substance trap groove | channel 20 2nd frame 28 Support member 30 Connector opening 40 surface Optical component 50 LED light source unit 55 LED substrate

Claims (5)

A dust-proof structure of a planar light source that stores and holds a planar optical component in a first frame and a second frame,
By engaging the engaging portion formed on the outer wall of the first frame and the engaged portion formed on the outer wall of the second frame, the first frame and the second frame are Concatenated,
An auxiliary wall along the outer wall is formed on the first frame, the top of the auxiliary wall abuts on the inner peripheral surface of the second frame, and a foreign substance trap groove is formed between the outer wall and the auxiliary wall. And
A connector opening is formed in the first frame, the connector opening is closed with an LED board, and a connector exposed through the connector opening is provided on the first surface of the LED board,
The top portion of the second auxiliary wall formed on the second frame and the planar optical component are pressed to the peripheral portion of the second surface of the LED substrate,
A support member that contacts the second surface of the LED substrate so as to face the connector is formed on the second frame, and prevents the LED substrate from shifting or deforming to the second surface side. A dustproof structure for a planar light source characterized by the above. The dust-proof structure for a planar light source according to claim 1 , wherein the support member has a wall structure formed in parallel with the auxiliary wall. The dustproof device for a planar light source according to claim 1 or 2 , wherein the outer wall and the auxiliary wall are substantially continuous without a gap.   The dustproof device for a planar light source according to claim 1, wherein a groove is formed in the auxiliary wall, and a claw of the planar optical member is accommodated in the groove. A dust-proof structure of a planar light source that stores and holds a planar optical component in a first frame and a second frame,
By engaging the engaging portion formed on the outer wall of the first frame and the engaged portion formed on the outer wall of the second frame, the first frame and the second frame are Concatenated,
A connector opening is formed in the first frame, the connector opening is closed with an LED board, and a connector exposed through the connector opening is provided on the first surface of the LED board,
The top portion of the second auxiliary wall formed on the second frame and the planar optical component are pressed to the peripheral portion of the second surface of the LED substrate,
A support member that contacts the second surface of the LED substrate so as to face the connector is formed on the second frame, and prevents the LED substrate from shifting or deforming to the second surface side. A dustproof device for a planar light source.

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