JPH0448502A - Illumination device - Google Patents

Abstract

PURPOSE:To effectively press a low-pressure discharge lamp with hook pieces by integrally cutting up the hook pieces from the bottom wall of a casing, twisting the hook pieces, and bringing the tip sections from twist sections into contact with bent sections of the discharge lamp. CONSTITUTION:Hook pieces 15... are integrally cut up and formed on the bottom wall of a casing 1. The hook pieces 15... are erected to be faced to the inside faces of U-shaped bent sections 9a, 9b, 9c of a fluorescent lamp 6 respectively. The hook pieces 15... are twisted in the perpendicular direction in the middle, and the tip sections from twist sections 16 are slantly deformed by caulking and brought into contact with inside faces of the U-shaped bent sections 9a, 9b, 9c of the lamp 6. The fluorescent lamp 6 is supported by elastic lamp holders 12, 13, 13 and the hook pieces 15... and unmoveably fixed to the casing 1.

Description

[Detailed description of the invention] [Object of the invention] (Industrial application field) The present invention uses a low pressure discharge lamp such as a fluorescent lamp as a light source,
The present invention relates to a lighting device suitable for backlights of liquid crystal televisions and liquid crystal meters.

(Prior technology) LCD televisions, LCD meters, etc. are designed to illuminate the liquid crystal surface by shining light on the back of the transmissive liquid crystal panel. A device that emits light with uniform brightness as a whole is required.

This type of backlight has traditionally housed a hot cathode or cold cathode fluorescent lamp in a shallow dish-shaped casing.
The light emitted from this lamp is reflected by a reflective surface formed on the casing and irradiated toward the opening of the casing, and is illuminated on the back of the liquid crystal panel through a light diffusing and transmitting plate installed in this opening. equipment is used.

When a hot cathode or cold cathode fluorescent lamp is used as a light source, compared to an incandescent lamp, these fluorescent lamps have superior luminous efficiency, generate less heat, have a longer lifespan, and have a longer discharge path, so their light emitting area is smaller. It has the advantage that it is large and the light distribution can be easily made uniform. In particular, in the case of fluorescent lamps, it is easy to configure the discharge path into a bent shape, such as a U-shape or a W-shape. This is advantageous for illuminating a display surface with uniform brightness.

(Problem to be Solved by the Invention) Incidentally, in order to fix such a bent fluorescent lamp inside the casing, it is necessary to hold the bulb with some kind of support means.

In this case, using special support means increases the number of parts and
There are some problems, such as the labor required to fix the lamp.

In addition, if the straight part of the bent bulb is held down when fixing the lamp with some kind of support means, this effective light will be blocked and the arrangement will be There is a concern that the light distribution will be disrupted.

The present invention aims to provide a lighting device that can fix a bent low-pressure discharge lamp to a container with a simple structure and that hardly disturbs the light distribution.

[Structure of the Invention] (Means for Solving the Problems) In the present invention, a locking piece is integrally cut and raised from the bottom wall of a casing, this locking piece is twisted, and the tip portion is lower than the twisted portion. It is characterized in that the locking piece is brought into contact with the bent part of the low-pressure discharge lamp and the low-pressure discharge lamp is held down by this locking piece.

(Function) According to the present invention, the locking piece is integrally cut and raised from the bottom wall of the casing, and the locking piece is deformed to hold down the discharge lamp. Since the retaining piece is twisted in the middle, its rigidity is improved and there is no worry that the cut and raised piece will return to its original shape and become deformed. Since the tip of the locking piece presses the bent portion of the discharge lamp rather than the twisted portion, movement of the lamp can be prevented with a small number of locking pieces.

Further, since the bent portion is the brightest part of the lamp, even if the locking piece comes into contact with this part, it is unlikely to have a significant adverse effect on the light distribution characteristics.

(Example) The present invention will be described below based on an example shown in the drawings.

In the figure, reference numeral 1 denotes a tray-shaped casing with an open top, made of a metal such as conductive aluminum, and has a reflective surface 2 formed on its inner surface.

The upper surface opening of the casing 1 is used as an irradiation part, and a fixed circumferential flange 3... is formed in this opening, and a screw hole 4... is formed in the fixed circumferential flange 3... There is.

A bent fluorescent lamp 6 is accommodated in the casing 1 . The fluorescent lamp 6 of this embodiment is a W-shaped cold cathode fluorescent lamp. That is, 7 is a valve bent into a W-shape, and this valve 7 has straight portions 8a that are substantially parallel to each other.

8b, 8c, and 8d, and these straight portions 8a, 8
b, 8c, and 8d are U-shaped bent portions 9a.

9b and 9c are electrically connected. Cold cathode type electrodes 10.10 are sealed to both ends of the bulb 7, and a cap 11.11 is attached to the end.

A phosphor coating (not shown) is formed on the inner surface of the bulb 7, and a predetermined amount of mercury and a starting rare gas such as argon or xenon are sealed inside the bulb 7.

The fluorescent lamp 6 having such a structure is housed in the casing 1 and supported by elastic lamp holders 12, 13, 13 made of silicone rubber or the like.

One elastic lamp holder 12 is disposed inside the other end of the casing 1, and has recesses 12a and 12 into which two U-shaped bent portions 9a and 9b of the W-shaped bulb 7 fit.
It has b. Fixing pieces 21.21 are integrally formed at the lower end of the elastic lamp holder 12, and fixing holes 22.22 are formed in these fixing pieces 21.21.

These fixing holes 22.22 have locking pieces 15.15 to be described later.
is inserted through the elastic lamp holder 12, thereby fixing the elastic lamp holder 12 to the casing 1.

Further, another elastic lamp holder 13.13 is fitted into a notch 14.14 formed at one end of the casing 1,
Insertion holes 13a and 13B through which the ends of the lamps 6 are passed
have.

Therefore, the fluorescent lamp 6 has two U points on the bulb 7.
The bent portions 9g, 9b and both ends are supported on the casing 1 via elastic lamp holders 12, 13, 13, respectively.

In this case, since these elastic lamp holders 12, 13, and 13 are made of an elastic material such as rubber, there is a possibility that the lamp 6 may move in the axial direction of the straight portion due to vibration or impact.

For this purpose, the lamp 6 is fixed to the casing 1 by the following means.

That is, locking pieces 15 are integrally cut and raised on the bottom wall of the casing 1. These locking pieces 15・
... are respectively erected to face the inner surfaces of the U-shaped bent portions 9a, 9b and 9c of the fluorescent lamp 6.

The middle portions of these locking pieces 15 are twisted in the right angle direction, and the tip portions are caulked obliquely from this twisted portion 16 to form a U-shaped bend in the lamp 6, as shown in FIG. It is in contact with the inner surfaces of portions 9g, 9b and 9c.

Therefore, the fluorescent lamp 6, the elastic lamp holder 12
．． 13.13 and the locking piece 15...
It is immovably fixed to the casing 1.

As described above, the locking piece 15 is attached to the elastic lamp holder 1.
The elastic lamp holder 12 is inserted into the fixing hole 22.22 formed in the elastic lamp holder 12, and is also used for fixing the elastic lamp holder 12.

Incidentally, the fluorescent lamp 6 is electrically connected to a high frequency lighting circuit device (not shown) and is turned on at high frequency.

A light diffusing and transmitting plate 25 is attached to the opening of the casing 1. The light diffusing and transmitting plate 25 is made of acrylic resin or the like and has a milky white color and has a light diffusing and transmitting function. , 8b, 8c, and 8d are formed with thick portions 26.... The thickness of these thick portions 26 gradually becomes thinner as they move away from the valve 7.

Connecting holes 27 are formed at the four corners of the light diffusing and transmitting plate 25, and screws 28 are inserted into these holes 27.

The screws 28 are inserted through the connection holes 27 of the light diffusing and transmitting plate 25 and are screwed into the threaded holes 4 formed in the upper opening of the casing 1.

Therefore, the light diffusing and transmitting plate 25 is connected to the casing 1 by screws 28 .

The operation of the embodiment with such a configuration will be explained.

When the fluorescent lamp 6 is turned on by applying high frequency power, the lamp 6 emits light in a shape along the W-shaped bulb 7.

A part of the light emitted from the fluorescent lamp 6 is transmitted to the casing 1.
The remaining light is reflected by the reflective surface 2 of the opening and directed toward the light diffusing/transmitting plate 25 at the opening, and the remaining light is directed directly toward the light diffusing/transmitting plate 25. Therefore, almost all of the light emitted from the lamp 6 is irradiated to the outside through the light diffusing and transmitting plate 25.

In this case, the substantially parallel straight portion 8a of the W-shaped valve 7,
8b, 8c, and 8d are formed on the outer surface of the light diffusing and transmitting plate 25, so that the thick portion 26 exists directly above the bulb 7, and this thick portion 26 prevents light from flowing. In addition to reducing the amount of light transmitted, since the wall thickness becomes thinner as the distance from the thick portion 26 increases, the amount of light transmitted increases. Therefore, the light diffusing and transmitting plate 25
has the effect of eliminating brightness unevenness by itself.

For this reason, the brightness distribution on the light diffusing and transmitting plate 25 is equalized, uneven brightness is reduced, and uniform brightness can be achieved over the entire surface.

This fluorescent lamp 6 has a lamp holder 1 made of an elastic material.
Since it is not only supported by 2.13.13 but also held down by the locking pieces 15 cut and raised from the bottom wall of the casing 1, there is no need to worry about it moving within the casing 1.

In particular, even if vibrations or shocks are applied, they are absorbed by the lamp holders 12, 13, 13 made of an elastic material, so damage is prevented, and the locking pieces 15 prevent movement.

Since the locking pieces 15 are integrally formed by cutting and raising the bottom wall of the casing 1, no special lamp supporting parts are required. Since these locking pieces 15 are twisted in the middle, the rigidity is increased, and recovery deformation after cutting and raising is less likely. Therefore, the mechanical strength is increased, and the fluorescent lamp 6 can be firmly supported even when vibrations or shocks are applied to the fluorescent lamp 6.

Furthermore, since the tip of the twisted portion 16 can be brought into contact with the bulb 7 by caulking, the work of fixing the lamp 6 is easy.

These locking pieces 15 hold down the inner surfaces of the U-shaped bent portions 9a, 9b, and 9C of the fluorescent lamp 6, so even if there are only a few locking pieces 15, the fluorescent lamp 6 can be held down. Prevents movement forward, backward, left, right, and up and down.

Since these bent parts 9a, 9b, and 9c are the brightest parts of the lamp, these bent parts 9a, 9b, and 9c are the brightest parts of the lamp, so these bent parts 9a, 9b, and 9c are the brightest parts of the lamp.
Even if the locking pieces 15 come into contact with each other and are slightly interrupted, the light distribution characteristics will not be significantly affected, and the presence of the locking pieces 15 can be ignored.

Moreover, since these locking pieces 15 also have the function of fixing the elastic lamp holder 12, the elastic lamp holder 12 can be easily supported.

Note that the present invention is not limited to the above embodiments,
For example, the fluorescent lamp may be U-shaped instead of W-shaped, and one or more fluorescent lamps may be used.

Furthermore, the cross-sectional shape of the bulb 7 in the lamp 6 (the cross-sectional shape of the discharge space) is not limited to a circular shape, but may be a flat shape. If the lamp has a flat shape, the side surface with a large light emitting area can face the light diffusing and transmitting plate 25, and the effective utilization rate of the light emitted from the lamp becomes high.

Furthermore, the present invention may be a rare gas discharge lamp in which the bulb is not filled with mercury but only with a rare gas.

The lamp 6 is not limited to one that is lit at high frequency.

[Effects of the Invention] As explained above, according to the present invention, the locking piece is integrally cut and raised from the bottom wall of the casing, and the locking piece is deformed to hold down the discharge lamp, so that a special lamp support means is provided. This is not necessary, and since the locking piece is twisted in the middle, its strength is increased and it is less likely to be deformed upon return, thus supporting the lamp reliably. In addition, since the locking piece holds the bent part of the discharge lamp, movement of the lamp can be prevented with a small number of locking pieces, and since the bent part is the brightest part of the lamp, it is possible to prevent the lamp from moving. Even if the locking piece comes into contact with the light distribution characteristics, it hardly affects the light distribution characteristics.

[Brief explanation of drawings]

The drawings show one embodiment of the present invention, with Fig. 1 being an exploded perspective view of the entire structure, Fig. 2 being a plan view with the light diffusing and transmitting plate removed, and Fig. 3 taken along the line ■-■ in Fig. 2. FIG. 1...Casing, 6...Fluorescent lamp, 7...
Bulb, 9a, 9b, 9c--bent portion, 12°13...lamp holder, 15...locking piece,
16...Twisted portion, 25...Light diffusing and transmitting plate. Applicant's agent Patent attorney Takehiko Suzue

Claims (1)

[Scope of Claims] An illumination device in which a bent low-pressure discharge lamp is housed in a metal casing with an irradiation part provided on one side, and the light emitted from the discharge lamp is irradiated from the irradiation part of the casing. In the device, cut and raise the locking piece integrally from the bottom wall of the casing,
A lighting device characterized in that the locking piece is twisted and the tip of the twisted portion is brought into contact with the bent portion of the discharge lamp, thereby holding down the low-pressure discharge lamp with the locking piece.