JP2007018880A - Lighting system for liquid crystal panel - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To easily connect the terminal pin of a discharge lamp to a circuit board. <P>SOLUTION: When assembling this lighting system, if the terminal pin 1a of the discharge lamp 1, bent almost perpendicular toward the rear, is inserted in a through hole 23a bored through the recessed housing part 23 of a reflector 2, the terminal pin 1a is connected to a connecting part 40, mounted to a circuit board 4 attached to the back face side of the reflector 2. Accordingly, a process of connecting the terminal pin 1a to the core wire 61 of a cable 60 as in the conventional example, and a process of connecting a connector 62 attached to the tip of the cable 60 to a receiving side connector 63 mounted to the circuit board 4 can be dispensed with, and the terminal pin 1a of the discharge lamp 1 can be easily connected to the circuit board 4. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to an illumination device for a liquid crystal panel that illuminates a transmissive liquid crystal panel from behind.

An illuminating device for a liquid crystal panel (so-called backlight) that illuminates a transmissive liquid crystal panel from the back side is provided with a plurality of straight tube type discharge lamps juxtaposed in parallel with the back surface of the liquid crystal panel, and behind the discharge lamps. A reflector that reflects the light emitted from the discharge lamp to the front, a lighting device that supplies power to the discharge lamp through the terminal pins and lights it, and at least a part of the circuit components that make up the lighting device are mounted And a circuit board disposed on the back side of the reflecting plate (see, for example, Patent Document 1). In such a conventional example, as shown in FIG. 6, the terminal pins 1 a of the plurality of discharge lamps 1 are connected to the core wire 61 of the cable 60 by an appropriate method such as soldering or caulking, and are attached to the tip of the cable 60. The connector 62 is electrically connected to the circuit board 4 via the connector 62.
JP 2003-178616 A

  However, in the above conventional example, it is necessary to connect the core wire 61 of the cable 60 to the terminal pins 1a of the plurality of discharge lamps 1 and connect the connector 62 of the cable 60 to the connector 63 on the receiving side of the circuit board 4. Therefore, there has been a problem that much labor and time are required for the connection work of the terminal pins 1a.

  The present invention has been made in view of the above circumstances, and an object of the present invention is to provide an illumination device for a liquid crystal panel that can easily connect terminal pins of a discharge lamp and a circuit board.

  In order to achieve the above object, the invention of claim 1 is an illuminating device for a liquid crystal panel that illuminates a transmissive liquid crystal panel from the rear side, and is juxtaposed in parallel with the back surface of the liquid crystal panel and has terminals at both ends. A plurality of straight tube discharge lamps provided with pins, a reflector disposed behind the discharge lamps to reflect light emitted from the discharge lamps forward, and power to the discharge lamps via terminal pins A lighting device that is supplied and lit, a circuit board on which at least a part of circuit components constituting the lighting device is mounted, and a connection that is mounted on the circuit board and receives the tip of the terminal pin and electrically connects to the lighting device And a section.

  The invention of claim 2 is characterized in that, in the invention of claim 1, a circuit board is disposed on the back side of the reflector.

  The invention of claim 3 is characterized in that, in the invention of claim 2, the terminal pin is bent backward, and a through-hole through which the bent terminal pin is inserted is provided in the reflecting plate.

  According to the present invention, there is an effect that the terminal pin of the discharge lamp and the circuit board can be easily connected by connecting the terminal pin of the discharge lamp to the connection portion mounted on the circuit board.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.

  In this embodiment, as shown in FIGS. 2 to 5, a plurality of (12 in the illustrated example) straight tube-shaped discharge lamps 1 juxtaposed in parallel with the back surface of the liquid crystal panel, and behind the discharge lamp 1. A reflector 2 that is disposed and reflects the light emitted from the discharge lamp 1 forward (upward in FIG. 2), and a plate-like diffusion that is disposed between the liquid crystal panel and the discharge lamp 1 and diffuses the incident light. A lighting device (not shown) for supplying electric power to the discharge lamp 1 (electrodes thereof) via the plate 3 and terminal pins 1a provided at both ends of the discharge lamp 1, and circuits constituting the lighting device Two circuit boards 4 on which at least a part of the component is mounted and disposed on the back side of the reflecting plate 2, a diffusion sheet 5 disposed in front of the diffusion plate 3, and a front of the diffusion sheet 5 The lens sheet 6 provided and the optical sheet 7 disposed in front of the lens sheet 6 The holding frame 8 disposed in front of the optical sheet 7, and the diffusion plate 3 and the three types of sheets 5 to 7 are sandwiched between the reflection plate 2 and the holding frame 8 through the holding frame 8. And a metal frame 9 that sandwiches and supports a liquid crystal panel (not shown).

  The discharge lamp 1 includes a rod-shaped glass tube, a pair of electrodes (not shown) provided at both ends of the glass tube, and a terminal pin 1a that is connected to the electrode at one end and led out of the glass tube. Is a cold cathode fluorescent lamp. The glass tube has a diameter of several mm and a total length of several tens of centimeters. The terminal pin 1a is bent rearward at a substantially right angle.

  The diffusing plate 3 is formed in a thin flat plate shape with a translucent material such as acrylic resin, for example, diffuses light emitted from the discharge lamp 1 and irradiates it forward, and has a bowl-shaped notch 3a. Are provided at the four corners, and recesses 3b that are recessed inward are provided at the centers of both sides facing in the longitudinal direction.

  The circuit board 4 is a printed wiring board in which a wiring pattern is printed on a strip-shaped insulating substrate, and circuit components (not shown) constituting a lighting device (such as an inverter circuit) for lighting the discharge lamp 1 are mounted. ing. In addition, since this kind of lighting device is conventionally well-known, illustration and description are abbreviate | omitted. Further, on one edge along the longitudinal direction of the circuit board 4, connection portions 40 to which the terminal pins 1 a of the discharge lamp 1 are inserted and connected are arranged in a line at equal intervals.

  As shown in FIG. 1, the connecting portion 40 receives a box-shaped housing 41 having an insertion port 42 into which the terminal pin 1 a is inserted, and a terminal pin 1 a housed in the housing 41 and inserted through the insertion port 42. A blade receiver 43. The blade receiver 43 is formed by processing a metal plate having elasticity into a substantially C shape, and is mounted on the circuit board 4 by soldering the terminals 43a through which the through holes 4a of the circuit board 4 are inserted. That is, the terminal pin 1a and the lighting device are electrically connected (connected) through the blade receiver 43.

  The optical sheet 7 is used for irradiating the liquid crystal panel by separating and transmitting incident light into a vertical polarization component or a horizontal polarization component. Further, the diffusion sheet 5 mainly plays a declination effect of the light emitted from the diffusion plate 3 and a diffusion effect of light retroreflected from the lens sheet 6. Further, the lens sheet 6 has a main role of declination of light emitted from the diffusion sheet 5. Here, these three types of sheets 5 to 7 are also provided with notches and recesses of the same shape and size at the same position as the diffusion plate 3. In addition, since the function, material, etc. of these three types of sheets 5 to 7 are conventionally known, detailed description thereof will be omitted.

  The holding frame 8 is made of a synthetic resin molded product having a rectangular frame shape, and is disposed on the front side of the optical sheet 7. The metal frame 9 is formed in a rectangular frame shape by a metal material such as aluminum, is attached to the front surface side of the reflector 2 via the pressing frame 8, and supports the liquid crystal panel sandwiched between the pressing frame 8, The diffusing plate 3 and the three types of sheets 5 to 7 are sandwiched and supported between the reflecting plate 2 and the presser frame 8. In addition, what is necessary is just to perform the coupling | bonding of the metal frame 9 and the reflecting plate 2 by appropriate methods, such as screwing and caulking.

  The reflecting plate 2 is formed into a flat rectangular plate shape entirely by PBT resin, and a plurality of bowl-shaped reflecting surfaces 21 (12 in the illustrated example) are arranged in parallel on the front surface excluding the surrounding frame portion 20. Yes. Further, at the four corners of the front surface of the frame portion 20, substantially L-shaped positioning projections 22 project from the notches 3 a in order to position the diffusion plate 3. Further, storage recesses 23 that communicate with the reflection surface 21 and store the ends of the discharge lamp 1 are provided at substantially equal intervals on the front surfaces of the two frame pieces 20 a facing the longitudinal direction of the frame portion 20. Here, a through hole 23a penetrating in the front-rear direction is provided on the bottom surface (rear surface) of the storage recess 23, and the discharge lamp 1 is discharged with the end portion stored in the storage recess 23 as shown in FIGS. The terminal pin 1a of the lamp 1 is inserted through the through hole 23a. In addition, a holding plate 10 that holds the discharge lamp 1 housed in the housing recess 23 from the front is attached to both frame pieces 20a of the reflecting plate 2 on the front side. The pressing plate 10 is made of a synthetic resin molded product, has a strip-shaped main portion 10a, a substantially U-shaped protruding wall 10b that protrudes forward from the front center of the main portion 10a, and a rear side from the back side of the main portion 10a. And a plurality of (in this embodiment, twelve) pressing pieces 10c that project from the storage recess 23 (see FIGS. 2 and 3). Here, cylindrical holding members 11 having opening grooves along the axial direction are extrapolated at both ends of the discharge lamp 1, and the pressing plate 10 is attached to the frame piece 20a by an appropriate method such as screwing or caulking. If it attaches to, the discharge lamp 1 will be supported indirectly by the front-end | tip of the holding | suppressing piece 10c contacting the holding member 11. The diffusing plate 3 is placed on the front side of the pressing plate 10 so that the recess 3b is brought into contact with the protruding wall 10b of the pressing plate 10.

  Thus, when assembling the present embodiment, if the terminal pin 1a of the discharge lamp 1 bent rearward at a substantially right angle is inserted into the through hole 23a provided in the housing recess 23 of the reflector 2, the reflector Since the terminal pin 1a is connected to the connecting portion 40 mounted on the circuit board 4 attached to the back side of the terminal 2, the step of connecting the terminal pin 1a to the core wire 61 of the cable 60 as in the conventional example, The step of connecting the connector 62 attached to the tip of the cable 60 to the receiving connector 63 mounted on the circuit board 4 is not necessary, and the connection between the terminal pin 1a of the discharge lamp 1 and the circuit board 4 is easy. It can be done.

  By the way, the glass tube may thermally expand due to self-heating during lighting, and the entire length of the discharge lamp 1 may be extended. At this time, if both ends of the discharge lamp 1 are firmly fixed, the glass tube bends as much as the entire length is extended, and there is a possibility that uneven brightness occurs due to the bending. On the other hand, in this embodiment, since the terminal pin 1a of the discharge lamp 1 is bent backward, even if the entire length of the discharge lamp 1 is extended by the thermal expansion of the glass tube, the terminal pin connected to the connecting portion 40 Since the la is bent in the axial direction of the discharge lamp 1, the elongation due to thermal expansion can be absorbed, and the occurrence of uneven brightness due to the bending of the discharge lamp 1 can be prevented.

FIG. 5 is a partially omitted cross-sectional view illustrating a configuration of a connection portion mounted on a circuit board and terminal pins of a discharge lamp according to an embodiment of the present invention. It is an exploded perspective view same as the above. It is the perspective view seen from the front which shows the discharge lamp, the reflecting plate, and the pressing board 10 in the same as the above. It is the perspective view seen from the back which shows the reflecting plate and circuit board 4 in the same as the above. It is the perspective view seen from the back same as the above. It is explanatory drawing explaining the connection structure of the discharge lamp and circuit board in a prior art example.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Discharge lamp 1a Terminal pin 4 Circuit board 40 Connection part

Claims (3)

  A lighting device for a liquid crystal panel that illuminates a transmissive liquid crystal panel from behind, and a plurality of straight tube type discharge lamps juxtaposed in parallel with the back surface of the liquid crystal panel and provided with terminal pins at both ends. A reflector that is disposed behind the discharge lamp and reflects light emitted from the discharge lamp forward; a lighting device that supplies power to the discharge lamp via a terminal pin; and a circuit that constitutes the lighting device A lighting device for a liquid crystal panel, comprising: a circuit board on which at least a part of the component is mounted; and a connection portion mounted on the circuit board and receiving a tip portion of a terminal pin and electrically connected to a lighting device .   2. A lighting device for a liquid crystal panel according to claim 1, wherein a circuit board is disposed on the back side of the reflector.   3. The illuminating device for a liquid crystal panel according to claim 2, wherein the terminal pin is bent rearward, and a through hole through which the bent terminal pin is inserted is provided in the reflecting plate.

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