JPH02201804A - Lighting equipment - Google Patents

Abstract

PURPOSE:To reduce an area to be adhered without presence of adhesives at a position near a heater and a lamp by adhering a heater to an insulating film with a continuous outer block larger than an outer block of the heater. CONSTITUTION:Three reflecting projected strip members 2 are fixed at the bottom of a casing 1 formed of synthetic resin in a tray shape of a lighting equipment by a lock pin 3 and a reflecting surface 5 is formed on the top of the number 2 to house a bending fluorescent lamp 6. A lamp 7 bent in a shape of W is used for this lamp 6 and an electric heater 15 is installed on the bottom of the casing 1, and both upper and lower sides of the heater body 16 of the heater 15 are formed as a laminator by heat resistant insulating films 17, 18. An insertion through hole 19 opposed to a fitting hole 4 made in the bottom wall of the casing 1 is made in these films 17, 18 and the pin 3 of the member 2 is passed into the insertion through hole 19 and locked in the fitting hole 4.

Description

DETAILED DESCRIPTION OF THE INVENTION [Object of the Invention] (Industrial Application Field) The present invention relates to an illumination device that uses a discharge lamp such as a fluorescent lamp as a light source and is suitable for use as a backlight for a liquid crystal television or a liquid crystal meter.

(Conventional technology) LCD televisions, LCD meters, etc. are designed to illuminate the liquid crystal surface by shining light from the back of the liquid crystal panel. Therefore, a lighting device that can emit light with even brightness is required.

This type of backlight has traditionally housed a hot cathode or cold cathode fluorescent lamp as a light source in a casing that has a reflective surface on its inner surface, and the light emitted from this lamp is reflected by the reflective surface to illuminate the casing. A lighting device is used in which light is emitted to the outside through a light diffusing and transmitting plate installed in an opening, that is, an irradiation part.

When a hot cathode or cold cathode fluorescent lamp is used as a light source, these fluorescent lamps have superior luminous efficiency and generate less heat than incandescent lamps, have a long lifespan, and have a long discharge path, so their light emitting area is large. , it has the advantage that the light distribution tends to be uniform.

In the case of a fluorescent lamp, it is easy to configure the discharge path into a bent shape, such as a U-shape or a W-shape, and a fluorescent lamp with such a bent shape has a wider light-emitting surface in plan view. This is advantageous in irradiating a display surface having a predetermined spread with uniform brightness.

By the way, when low-pressure mercury vapor discharge lamps, such as the fluorescent lamps mentioned above, are generally started in a low-temperature atmosphere, electrons are not emitted smoothly, resulting in a high starting voltage and a long rise time. There is a problem with
Furthermore, if the ambient temperature is low during lighting, the vapor pressure of the luminescent metal or luminescent gas enclosed therein will be low, causing problems such as a decrease in luminous efficiency.

In order to eliminate such light emission characteristics, a method of heating the discharge lamp with a heater has been proposed.

By heating the discharge lamp with a heater, the starting characteristics and light emission characteristics can be improved without being affected by the ambient temperature.

(Problem to be Solved by the Invention) In the past, the heater was formed in the shape of a band along the tube axis of the discharge lamp, and this band-shaped heater was bonded to the bottom of the casing with adhesive at a position close to the lamp. Ta.

However, in this configuration, the bottom surface of the heater is bonded to the bottom surface of the casing via an insulating material, so
When the heater is energized and heated, the adhesive is heated, and even when the heater is not energized, when the lamp is on, the heat from the lamp is transferred to the adhesive via the heater that is close to the lamp, and the adhesive is heated. There is a drawback that the heater easily peels off due to thermal deterioration.

Furthermore, when the discharge path is curved, the heater is also formed in a curved shape along the tube axis of the discharge lamp, and it takes time and effort to join such a curved heater to the casing. Since each bent portion must be adhered to the casing while taking positioning into consideration, there is a problem in that the adhesion work requires time and effort.

The present invention aims to provide a lighting device in which heat deterioration of the adhesive is prevented, the heater is difficult to peel off over a long period of time, and bonding work is facilitated.

[Structure of the invention]

(Means for Solving the Problems) A first aspect of the present invention is to attach a heater to a continuous insulating film having a larger outline than the outer circumference of the heater, and attach this film to the bottom surface of a casing at a position away from the heater. It is characterized by being glued.

The second aspect of the present invention is that when the discharge lamp is a bending electric lamp,
In a lighting device having a structure in which a reflective ridge member is provided between adjacent straight parts of the bent electric lamp, and this reflective ridge member is attached to the bottom surface of the casing, the insulating film to which the heater is attached is attached to the reflective ridge member. It is characterized in that it is held between the protrusion member and the bottom surface of the casing.

(Function) According to the first aspect of the present invention, a heater shaped along the tube axis of a discharge lamp is attached to a continuous insulating film having a larger area than the heater, and this film is placed at a position away from the heater. Since the adhesive is bonded to the bottom surface of the casing, there is no adhesive near the heater and lamp, so the adhesive does not easily receive heat from the heater or lamp, preventing thermal deterioration and making it difficult to peel off. Further, the number of places where the film is bonded to the casing may be small, or the bonding area may be small, and the film is not restricted by the shape of the heater, making installation easier.

Further, according to the second aspect of the present invention, since the insulating film to which the heater is attached is sandwiched between the reflective protrusion member and the bottom surface of the casing, there is no need to worry about the film coming off because it is prevented from floating in the middle. This also makes installation easier.

(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, which is made of synthetic resin such as polycarbonate, and this top opening serves as an irradiation section.

For example, three reflective strip members 2, 2.2 are attached to the bottom surface of the casing 1 in substantially parallel manner.

These reflective ridge members 2, 2.2 are made of synthetic resin such as polycarbonate, and have a substantially triangular cross section as shown in FIG. These reflective ridge members 2, 2.2 are integrally formed with locking pins 3 protruding from their lower surfaces, and the locking pins 3 are inserted into mounting holes 4 formed in the bottom wall of the casing l. ... are inserted and locked, whereby these reflective protrusions 2, 2.2 are fixed to the casing l.

Incidentally, the upper surface of the reflective protrusion members 2, 2.2 is a reflective surface 5 made of white or aluminum vapor deposited film.

A bent fluorescent lamp 6 is accommodated in the casing l. In this embodiment, a W-shaped cold cathode fluorescent lamp is used. That is, 7 is a valve bent and formed into a W-shape, and this valve 7 has straight parts 8a that are substantially parallel to each other,
8b, 8c, and 8d, and these straight portions 8
a, 8b, 8c, 8d are U-shaped bent parts 9a,
9b and 9c are conductive. Cold cathode type electrodes 10a, 10b are sealed to both ends of the bulb 7, and caps 11a, llb are attached to the ends.

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 configuration is housed in the casing l, in this case the straight part 8a of the bulb 7.

8b, 8c, 8d are installed so as to be substantially parallel to the bottom surface of the casing (■), and these straight parts 8a, 8b, 8
The reflective protruding members 2, 2.2 are interposed between the reflective protruding members 2, 2.2 between the adjacent straight parts 8a, 8b, 8c, and 8d. It is set up like this.

Note that the reflective protrusion members 2, 2.2 are located at the bent portion 9a of the bulb 7.
, 9b, and 9c are not present.

The fluorescent lamp 6 has caps 11a at both ends,
The mounting hole 12 formed in the side wall of the casing l by the llb section
... and is attached to the casing 1 by being fixed with an appropriate means such as adhesive.

A light diffusing and transmitting plate 13 is attached to the upper opening of the casing 1 . This light diffusing and transmitting plate 3 is made of milky white material such as acrylic resin and has a light diffusing and transmitting effect.
A thick portion 14 is formed in a portion facing the valve 7. The thickness of these thick portions 14 gradually becomes thinner as they move away from the valve 7.

An electric heater 15 is installed on the bottom surface of the casing 1.

This heater 15 has heat-resistant insulating films on both upper and lower surfaces of the heater body 16, such as polyester resin sheets 17 and 18.
It is formed by laminating.

The heater body 16 is W-shaped along the W-shaped bulb 7 of the cold cathode fluorescent lamp 6, and may be made of nichrome wire, but in the case of this embodiment, a film heater made of metal mesh is used. It is formed by cutting out a W-shape, or a serpentine heater is formed into a W-shape. The film-shaped heater body 16 cut into a W-shape is laminated on both upper and lower surfaces with the heat-resistant insulating films 17 and 18.
18 is each made of one continuous film having a larger outline than the outline of the heater main body 1B, and is formed into a substantially rectangular shape corresponding to the shape of the bottom surface of the casing 1, for example.

In such a heater 15, the lower insulating film 17 is adhered to the bottom surface of the casing 1 with an adhesive at locations remote from the bulb, for example, at least four corners.

In the case of this example, the heat-resistant insulating film is 17°18
Attachment holes 4 formed in the bottom wall of the casing l...
An insertion hole 19 facing the reflective protrusion member 2, 2.2 is formed with a locking pin 3 protruding from the lower surface of the reflective strip member 2, 2.2.
・ through these insertion holes 19... and this locking pin 3 ・
By inserting and locking ... into the mounting hole 4 of the casing 1, the intermediate portion of the heat-resistant insulating film 17.18 is sandwiched between the reflective protrusion members 2, 2.2 and the casing l. ing. This makes heat-resistant insulation film 17.18
A part of is fixed to the bottom surface of the casing l.

Note that the upper film 17 is white in order to have a light reflecting effect, but if a reflective surface is formed on the bottom of the casing 1, both films 17 and 18 may be transparent.

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

When the fluorescent lamp 6 is energized, 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 light is reflected by the bottom or top film 17 and directed toward the light diffusing/transmitting plate 13 at the opening, and the remaining light is directed directly toward the light diffusing/transmitting plate 13 . Therefore, almost all of the light emitted from the lamp 6 is irradiated to the outside through the light diffusing and transmitting plate 13.

In this case, the substantially parallel straight portion 8a of the W-shaped valve 7,
Reflective strip members 2, 2.2 are provided between 8b, 8c, and 8c.
are provided, these reflective protrusions 2゜2.2
reflect the light emitted from the straight parts 8a, 8b, 8c, and 8d upward, and
The brightness of the light diffusing and transmitting plate 13 facing between b, 8c and gd is increased. In other words, without the reflective protrusion member 2.2.2, the linear portions 8a, 8b,
8c.

The brightness of the portion facing 8c is reduced, and the straight portion 8a.

8b, 8e, and 8d, but when the reflective protruding members 2, 2.2 are provided, the reflection effect of the reflective protruding members 2, 2.2 causes the brightness to become uneven on the light diffusing and transmitting plate 13. The brightness of the opposing portions between the linear portions 8a, 8b, 8c, and 8c is supplemented to reduce uneven brightness in the direction perpendicular to the linear portions.

Moreover, since the thick part 14 is formed on the inner surface of the light diffusing and transmitting plate 13, the thick part 14 faces directly above the bulb 7,
Therefore, the amount of light transmitted through the thick portion is reduced, and the thick portion 14
As the distance from the wall decreases, the amount of light transmitted increases as the wall thickness decreases. Therefore, the light diffusing and transmitting plate 13 itself also functions to eliminate uneven brightness.

For this reason, the brightness distribution on the light diffusing and transmitting plate 13 has reduced brightness unevenness in both the direction perpendicular to the straight parts 8a, 8b, 8c, and 8d and the direction along the straight parts 8a, 8b, 8c, and 8d. This allows for uniform brightness over the entire surface.

In this embodiment, when the heater 15 is energized before starting, the heater 15 generates heat and heats the bulb 7 of the fluorescent lamp 6. For this reason, the mercury and rare gas inside the bulb 7 are warmed to some extent, making it easier to start discharging.
Further, after the start of discharge, the vapor pressure of mercury or rare gas easily rises to a predetermined pressure, and the luminous flux rises quickly. In other words, starting characteristics are improved even at low ambient temperatures.

During stable lighting, the light lamp 6 is heated by the heat generated by the heater 15, and the vapor pressure of mercury or rare gas is maintained at a predetermined pressure, thereby increasing the luminous efficiency.

For this reason, lamp efficiency can be improved even in a low temperature atmosphere.

Moreover, the heater 15 is constructed by laminating the film-shaped heater body 16 cut out in a W-shape with approximately square heat-resistant insulating films 17 and 18 made of a continuous film each having a larger outline than the outline of the heater body 16. ,
The W-shaped heater main body 16 can be handled as a substantially rectangular sheet, making the bonding work easier.

Then, the heater 15 is attached to the casing 1 with adhesive at the four corners.
Since the W-shaped heater body 16 can be attached to the bottom surface of the bulb 7, there are fewer adhesive points compared to the case where the W-shaped film-like heater body I6 is bonded over the entire surface. Easy to position,
Installation becomes easier.

Since this heater 15 is attached to the bottom surface of the casing 1 with adhesive at least four corners of the lamp 6 that are far from the bulb 7, even if the heater body 16 is energized and generates heat, the adhesive will not be heated. Furthermore, even if the heater 15 receives heat from the lamp 6 when the heater 15 is not used, since it is far from the lamp 6, the rate of temperature rise is small.

This prevents thermal deterioration of the adhesive, prolongs its life, and prevents the heater 15 from peeling off.

In addition, in the case of this example, the heat-resistant insulating film 17°18
The locking pin 3 of the reflective ridge member 2°2.2 was passed through the insertion hole 19 formed in the middle of the reflective ridge member 2゜2.2, and the reflective ridge member 2゜2.2 was held between the casing 1 and the reflective ridge member 2゜2.2. Heater 15
The middle part is fixed to the bottom of the casing 1, so there is no need to worry about this part coming off.

In this case, no special adhesive or parts are required for fixing the intermediate portion of the heater 15 to the bottom surface of the casing l, and no special work is required.

Note that the heater 15 may be energized only when the surrounding temperature is particularly low, and therefore the energization of the heater 15 may be controlled by detecting the ambient temperature with a sensor or the like.

Furthermore, a heater may be used to improve startup even when the surrounding temperature is high.

In the case of the above embodiment, the casing 1 is made of synthetic resin such as polycarbonate, but the present invention is not limited to this, and may be made of metal such as aluminum or other materials for high frequency shielding when the lamp is lit at high frequency. It may be made of conductive metal.

Further, the fluorescent lamp is not limited to a bent shape such as a W-shape or a U-shape, but may be a straight tube shape or the like, and one or a plurality of 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 13, and the effective utilization rate of the light emitted from the lamp becomes high.

When the cross-sectional shape of the bulb 7 is flat, it is desirable to pay attention to the following points.

That is, FIG. 3 shows a conventional U-shaped hot cathode type fluorescent lamp 20, and the cross-sectional shape of the bulb 21 is as follows.
A line X- along the direction of the adjacent straight parts 22a and 22b
As shown in X, it is flat.

In such a lamp 20, since the bulb 21 has a flat cross-sectional shape along the line XX, the arc during lighting tends to move along the line XX (long axis direction). . In addition to this, the arc is
It tends to take the shortest distance between 4a and 24b.

Therefore, the arc, as shown by the dashed diagonal line in Figure 3, is
In the bending portion 23, it follows a path inside the valve center line O-0, and as a whole tends to occur at a position eccentric from the valve center line 0-0.

In such a case, the light distribution characteristics will be distorted.

In order to prevent such a problem, as schematically shown in FIG. 4, baffle walls 25 may be provided at both base portions of the bent portion 23. In this way, the arc will bypass the baffle wall 25, and this detour path will be on or close to the bulb center line O-0, thus improving the light distribution characteristics.

The schematic configuration shown in FIG. 4 can be concretely realized by the structure shown in FIG. 5. That is, the structure shown in FIG. 5 is constructed by dividing the valve component into a plurality of parts and joining these parts, and the straight parts 22a, 22
The linear member 31a that constitutes b.

31b1 Connecting member 32 and baffle wall 2 constituting the bent portion 23
5 and a partition plate 33.

These linear members 31a, 31b, connecting member 32, and partition plate 33 are assembled by glass bonding each other.

Incidentally, by dividing into a plurality of parts in this manner, there is an advantage that the thickness of the phosphor wave film applied to the inner surface can be uniformly coated.

Furthermore, the present invention may be a rare gas discharge lamp in which only a rare gas is filled in the bulb without mercury.

〔Effect of the invention〕

As explained above, according to the first aspect of the present invention, a heater shaped along the tube axis of a discharge lamp is attached to a continuous insulating film having a larger area than the heater, and this film is separated from the heater. Since the adhesive is bonded to the bottom of the casing at the position where the adhesive is located, there is no adhesive near the heater or lamp, and therefore the adhesive is unlikely to receive heat from the heater or lamp, preventing thermal deterioration and making it difficult to peel off. Become. Further, the number of places where the film is bonded to the casing may be small, or the bonding area may be small, and the film is not restricted by the shape of the heater, making installation easier.

Further, according to the second aspect of the present invention, since the insulating film to which the heater is attached is sandwiched between the reflective strip member and the bottom surface of the casing, the midway portion of the film is prevented from floating, and there is no risk of it coming off. This also makes installation easier.

[Brief explanation of the drawing]

1 and 2 show one embodiment of the present invention, FIG. 1 is an exploded perspective view of the whole, FIG. 2 is a sectional view, and FIG. 3 is a conventional flat U-shaped fluorescent lamp. FIG. 4 is an explanatory diagram of an improved flat U-shaped low-light lamp, and FIG. 5 is an exploded diagram showing its specific structure. DESCRIPTION OF SYMBOLS 1... Casing, 2... Reflective protrusion, 3... Locking pin, 6... Fluorescent lamp, 7... Bulb, 8a
, sb, 8c. 8 d... Straight portion, 9a, 9b, 9a--Bending portion, 10a, 10b-electrode, 13... Light diffusing and transmitting plate, 15... Heater, IB... Heater main body, 1
7.18...Insulating film.

Claims (2)

[Claims] (1) A discharge lamp is housed in a casing that has an irradiation part on one side, and a heater is provided on the bottom of the casing to heat the discharge lamp along the tube axis of the discharge lamp, and radiation from the discharge lamp is provided. In the lighting device that irradiates the light from the irradiation part, the heater is attached to a continuous insulating film whose outline is larger than the outer circumference of the heater, and this film is attached to the bottom of the casing at a position away from the heater. A lighting device characterized by: (2) The above-mentioned discharge lamp is a bent discharge lamp, and in a lighting device in which a reflective ridge member is provided between adjacent straight parts of the bent discharge lamp, and this reflective ridge member is attached to the bottom surface of the casing, , the insulating film with the above heater attached,
The lighting device according to claim 1, wherein the lighting device is sandwiched between the reflective ridge member and the bottom surface of the casing.