JP2003317522A - Spacer for cold cathode tube and surface light source device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To detachably install a spacer for a cold cathode tube on a cold cathode tube. <P>SOLUTION: The spacer (3) for the cold cathode tube comprises a core (4) having two ends (4a, 4b) of a given length and composed of a flexible metal material or a flexible resinous material, and a sheath (5) coaxially enclosing the core (4) of a nearly uniform outer diameter and composed of an insulating resin. The cold cathode tube (1) is held with a predetermined space in a reflector (2). The spacer (3) has a sufficient mechanical strength because the core (4) has a higher tensile strength than the sheath (5). The spacer (3) is installed in C-shape or spirally around the cold cathode tube (1), so it is easily replceable or detachable from the cold cathode tube (1). <P>COPYRIGHT: (C)2004,JPO

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a spacer for a cold cathode fluorescent lamp, and more particularly to a spacer and a surface light source device which can hold a cold cathode fluorescent lamp at a certain distance with respect to a reflector and can be easily attached to and detached from the cold cathode fluorescent lamp.

[0002]

2. Description of the Related Art For example, utility model registration No. 2534634
As disclosed in the publication, an O-ring is attached to a light source of a surface light source device which is widely used as a light source for a backlight of a liquid crystal display. As shown in FIG. 6, the O-ring (14) attached to the conventional cold cathode fluorescent lamp is made of a non-conductive synthetic resin in a ring shape and is a long and narrow light source that is not adjacent to each other but has a certain interval. It is inserted into the cold cathode tube (1). The O-ring (14) is the reflector (2) shown in FIG.
The cold cathode tube (1) arranged inside the lamp is held in an insulated state with a certain distance from the reflector (2).

A rare gas and mercury vapor are enclosed in the cold cathode tube (1). Further, a reflection sheet (2a) for preventing light leakage from the cold cathode fluorescent lamp (1) is attached to the inner surface of the reflector (2), and a transparent or semitransparent end is provided in the opening of the reflector (2). A light guide (10) having a portion (10a) is connected. Light guide
A reflection layer (12) and a diffusion layer (11) that reflect and diffuse the light incident from the reflector (2) are provided in the (10). Also,
As shown in FIG. 6, the cold cathode tube (1) is connected to the power supply device (17) through the harness (16), and the harness (16) and the cold cathode tube are connected.
An elastic holder (15) is attached to the connecting portion with (1).

When a voltage is applied from the power supply device (17) to the cold cathode tube (1) through the harness (16) when the surface light source device shown in FIG. 7 is turned on, electrons are emitted in the cold cathode tube (1). Electrons collide with mercury atoms or molecules to generate ultraviolet rays, which are converted into visible rays by the fluorescent film formed on the inner wall of the cold cathode tube (1), and visible rays are emitted outside the cold cathode tube (1). Is released. The light emitted from the cold cathode tube (1) is reflected by the reflection sheet (2a).
The light enters the light guide body (10) after being reflected above or directly from the end portion (10a). The light that has entered the light guide (10) is
While partially diffusing the diffusion layer (11) and the reflection layer (12) provided on the front and back surfaces, part of the light is emitted through the diffusion layer (11) as illumination light with uniform brightness. The reflective sheet (2a) attached to the inner surface of the reflector (2) is selected from aluminum, gold, silver, copper or alloys thereof having excellent heat resistance and reflectivity in order to obtain illumination light with higher brightness. It is made of metal.

[0005]

[Problems to be Solved by the Invention] Conventional O-ring (14)
Has a very low mechanical strength because it is formed with a small diameter of, for example, milky white silicone rubber. In particular,
External force such as tensile force, compressive force, shock or vibration is applied to the cold cathode fluorescent lamp (1) when it is attached or detached or when the surface light source device is transported, so that the elastic force is lost due to breakage, relaxation or deterioration. And the life was short. Further, if the O-ring (14) is broken when it is broken when the cold cathode tube is inserted, if it breaks after the elastic holder (15) or the harness (16) is attached,
There was a drawback that exchange was not easy. Especially after delivery to the customer
Since the ring (14) may be broken, improvement has been required. Therefore, it is an object of the present invention to provide a spacer for a cold cathode tube and a surface light source device using the spacer for the cold cathode tube, which can be easily attached to and detached from the cold cathode tube.

[0006]

[Means for Solving the Problems] The cold cathode fluorescent lamp (1) is attached to an elongated cold cathode fluorescent lamp (1) arranged inside a reflector (2), and the cold cathode fluorescent lamp (1) is spaced from the reflector (2) at a constant interval. The cold cathode tube spacer according to the present invention for holding has two end portions (4a, 4a,
4b) a core (4) formed of a flexible metal material or a flexible resin material having a constant length, and concentrically fixed to the core (4) and having a substantially constant outer diameter and And a cover (5) formed of an insulating resin. The spacer allows the cold cathode tube (1) to be held at a predetermined distance from the reflector (2), but the core (4) has a higher tensile strength than the covering body (5), so the spacer has sufficient mechanical strength. Is added, and the service life of the spacer can be significantly extended. Moreover, since the spacer is wound around the surface of the cold cathode tube (1) in a C-shape or spirally attached, the cold cathode tube (1)
Even after attaching the to the elastic holder (15) or harness (16),
It can be easily attached to, detached from, or replaced with the cold cathode fluorescent lamp (1). In addition, since the spacer can be usually stored in a straight line or wound around a bobbin, the spacer can be appropriately cut into a required length according to the shape and length of the cold cathode tube (1). The surface light source device of the present invention is a cold cathode tube (1) having a cold cathode tube spacer (3) mounted thereon, and a cold cathode tube (1) via the spacer (3).
A reflector (2) placed adjacent to, and a reflector (2)
The light guide body (10) having the end portion (10a) arranged in the opening of the light guide body and the reflection layer (12) fixed to one surface of the light guide body (10).

[0007]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of a cold cathode tube spacer according to the present invention will be described below with reference to FIGS. 1 to 5, the same parts as those shown in FIGS. 6 to 7 are designated by the same reference numerals and the description thereof will be omitted. As shown in Figure 1,
The cold cathode tube spacer (3) according to the present invention has two end portions (4).
a core (4) concentrically formed with a core (4) formed of a flexible metal material having a, 4b) or a flexible resin material and having a constant length.
And a covering body (5) fixed to, having a substantially constant outer diameter, and made of a resin having an insulating property. core
(4) has a diameter of, for example, 0.1 to 0.2 mm, and is a flexible material such as a metal or polyacetal selected from stainless steel, titanium, iron, nickel, copper, gold or silver or alloys thereof, Polyester, polycarbonate resin,
It is made of an elastomer selected from acrylic resin and ABS resin. When the core (4) is made of an elastomer, a crystalline thermoplastic resin such as a copolyester can be used. If a transparent or semitransparent resin is used for the core (4), the light emitting area of the cold cathode tube (1) is not reduced. The coated body (5) for coating the core (4), for example,
With a diameter of 0.12-0.13 mm, silicone resin, polycarbonate resin, acrylic resin, polyamide resin,
If it is made of a transparent or translucent resin selected from polyethylene, polypropylene, ABS resin, polyvinyl chloride resin or an elastic resin having a white or reflective surface, the light emitting area of the cold cathode tube (1) is not reduced. it can. Inside the covering body (5), a scattering agent composed of silica powder, glass powder, metal powder, white pigment or the like may be mixed or coated.

Although not shown, a plurality of convex portions, concave portions or uneven portions are formed on the surface of the coating body (5) to increase the frictional force or slip resistance of the coating body (5) against the cold cathode fluorescent lamp (1). Thus, it is possible to prevent the spacer (3) from being displaced on the cold cathode tube (1). Further, as shown in FIG. 1, the covering body (5) can be formed with a uniform thickness over the entire length of the core (4).
As shown in (b), the covering (5) is formed into a spherical or cylindrical shape, or is formed into a bead shape at regular intervals in the length direction of the core (4), or the entire length of the core (4). Alternatively, it can be formed in a spiral shape at regular intervals. In Figure 1, the spacer (3)
Although an example of forming a straight line is shown, it may be formed in a short coil shape in advance.

The spacer (3) attached to the cold cathode tube (1) allows the cold cathode tube (1) to be held at a predetermined interval with respect to the reflector (2) shown in FIG. In (4), the tensile strength (tensile fracture strength), which is the maximum breaking stress per unit area, is larger than that of the covering body (5), so sufficient mechanical strength is imparted to the spacer and the service life of the spacer (3) is increased. It can be extended significantly. Further, the cold cathode fluorescent lamp has a spiral shape as shown in FIG. 2 or a C shape as shown in FIGS. 3 and 4.
Since the spacer (3) is wound around the surface of (1) and attached, even after the cold cathode tube (1) is attached to the elastic holder (15) or the harness (16), the cold cathode tube (1) is not attached to the cold cathode tube (1). It can be easily attached and detached or replaced. Further, since the spacer (3) can be usually stored in a linear shape or a coil shape or wound around a bobbin, the spacer can be appropriately cut to a required length according to the shape and length of the cold cathode tube (1). . If the spacer (3) is attached to the cold cathode fluorescent lamp (1), the reflector (2) arranged adjacent to the cold cathode fluorescent lamp (1) through the spacer (3) and the opening portion of the reflector (2). A light guide (10) in which the end (10a) is arranged,
A light source device including a reflection layer (12) fixed to one surface of the light guide (10) can be configured.

When the spacer (3) is attached to the cold cathode fluorescent lamp (1), the core (4) is deformed as shown in FIG. 2, and the covering (5) is attached to the surface of the cold cathode fluorescent lamp (1). The covering body (5) is spirally wound while abutting on it, and attached to the cold cathode tube (1). Spacer (3)
Is the cold cathode tube (1) due to the elastic force of the core (4) and the covering (5).
Self-held on top. The method of use is almost the same as the conventional example shown in FIG.

The spacer (3) of the present invention has the following effects. [1] The spacer (3) can be easily attached to and detached from the cold cathode tube (1). [2] The time required to replace the spacer (3) can be greatly reduced. [3] The spacer (3) can be appropriately cut into a desired length. [4] The spacer (3) has a large mechanical strength, and the life of the cold cathode tube (1) can be extended. [5] The service life of the spacer (3) is extended and the cold cathode tube is
The (1) can be reliably held apart from the reflector (2). [6] The amount of light attenuation by the spacer (3) is extremely small.

[0012]

As described above, according to the present invention, it is possible to obtain a spacer for a cold cathode tube which is easy to replace and has a long life, and a surface light source device using the spacer.

[Brief description of drawings]

FIG. 1 is a sectional view of a spacer for a cold cathode tube according to the present invention.

FIG. 2 is a schematic view of a cold cathode tube equipped with the cold cathode tube spacer of FIG.

FIG. 3 is a side view showing a mounted state of a spacer for a cold cathode tube according to the present invention.

FIG. 4 is a sectional view showing a mounted state of a spacer for a cold cathode tube according to the present invention.

FIG. 5 is a cross-sectional view showing another embodiment of the cold cathode tube spacer according to the present invention.

FIG. 6 is a schematic view of a conventional cold cathode tube equipped with a spacer for a cold cathode tube.

FIG. 7 is a sectional view of a conventional surface light source device.

[Explanation of symbols]

(1) ・ ・ Cold cathode tube, (2) ・ ・ Reflector, (4) ・ ・ Core, (4a, 4b) ・ ・ End, (5) ・ ・ Coating, (10) ・ ・
Light guide, (10a) ・ ・ End, (12) ・ ・ Reflective layer,

Claims (6)

[Claims] 1. A spacer, which is mounted on an elongated cold-cathode tube disposed inside a reflector and holds the cold-cathode tube at a constant distance from the reflector, the spacer having two ends. A core formed of a metal material or a flexible resin material with a constant length; and a cover body concentrically fixed to the core and formed of a resin having a substantially constant outer diameter and insulating properties. The core has a tensile strength higher than that of the covering, and is wound around the surface of the cold cathode tube in a C shape or in a spiral shape. 2. The spacer for a cold cathode tube according to claim 1, wherein a plurality of convex portions, concave portions or irregular portions are formed on the surface of the coating body. 3. The core comprises stainless steel, titanium, iron,
The metal is selected from nickel, copper, gold or silver or alloys thereof, or is formed from an elastomer selected from polyacetal, polyester, polycarbonate resin, acrylic resin, ABS resin, and the coating is silicone resin, polycarbonate resin, acrylic. The spacer for a cold cathode tube according to claim 1, which is formed of a resin selected from a resin, a polyamide resin, polyethylene, polypropylene, an ABS resin, and a polyvinyl chloride resin. 4. The cover has one of the following shapes with respect to the core: 1 A uniform thickness over the entire length of the core, 2 A spherical or cylindrical shape, which is constant in the length direction of the core. 4. The spacer for cold-cathode tube according to any one of claims 1 to 3, wherein the spacer is formed in a bead shape at intervals of 3 and is formed in a spiral shape at a full length of the core or at constant intervals. 5. The cold cathode tube spacer according to claim 1, wherein the cover is formed of a transparent or semitransparent resin or a resin having a white or reflective surface. 6. The cold cathode tube having the cold cathode tube spacer according to claim 1 mounted thereon, and the cold cathode tube disposed adjacent to the cold cathode tube through the cold cathode tube spacer. 2. A surface light source device comprising: the reflector; a light guide body whose end portion is arranged in an opening of the reflector; and a reflection layer fixed to one surface of the light guide body.