JP2008210802A - Cold-cathode lamp - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To realize a cold-cathode lamp useful for illuminated signboards for outdoors where the outside temperature decreases. <P>SOLUTION: A gap is assured between an inner peripheral wall of a lamp cover 8 and an outer peripheral wall of a cold-cathode lamp 2, and the cold-cathode lamp is stored inside a cylindrical lamp cover. A lamp pin 7 connected to an electrode wire 6 of the lamp is made to be a lamp body protruded from an end member 3 on both ends of the lamp cover. Air of a gap in the lamp cover with the cold-cathode lamp sealed is used as heating medium, and an inner diameter of the lamp cover as against the lamp outer diameter is set so that partial heat generation from the cold-cathode lamp can be spread all over the lamp by the heating medium. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a cold cathode lamp body, and more specifically, a cold cathode lamp that ensures the same usability as a conventional fluorescent lamp and has no decrease in life even when used at a low temperature, and is particularly useful for an electric decoration signboard for outdoor use. About the body.

  Since the cold cathode lamp does not have a filament in the electrode, it has a feature that a tube with a very thin tube diameter is possible. In addition, since it is strong against blinking lighting, it has a long life, and furthermore, since the structure and the structure of the lighting circuit are relatively simple, it has a feature that the cost can be reduced. Therefore, the storage space is limited, and it is frequently used for backlights of liquid crystal displays that are not premised on replacement by the purchaser. On the other hand, it is not widespread for general lighting fixtures for the reasons described later, but cold-cathode lamps are used as light sources in guide lights and electrical signs in buildings where a light source is arranged in a transparent housing. (Patent Document 1).

Generally, a cold cathode lamp is mounted on a mounted device by soldering electrode wires at both ends of the lamp to a power source conductor (Patent Document 2).
JP 2002-202738 A Japanese Patent Laid-Open No. 2002-324592 Japanese Patent Laid-Open No. 10-189259 JP 2000-313279 A

  By the way, a cold cathode lamp has characteristics that brightness and life are reduced at a low temperature as compared with a conventional hot cathode fluorescent lamp (hereinafter simply referred to as “fluorescent lamp”), and particularly when used for an outdoor appliance. In this case, the brightness decreases due to a decrease in the outside air temperature, and a sufficient lighting effect may not be obtained. Further, regarding the life, even if it is not below zero, the life becomes extremely short when the ambient temperature becomes 10 ° C. or less. The reasons for this are as follows: (1) When the lamp is lit continuously in a low temperature atmosphere, the oxidation of Hg (about 2.0 to 3.0 mg) enclosed in the lamp gradually proceeds, and the original characteristics of Hg are obtained. The lamp brightness decreases to 10% or less (rare gas discharge), and (2) For flicker, the lamp wall temperature does not increase due to self-heating in a low-temperature atmosphere, so the vapor pressure of the enclosed Hg also increases. The discharge becomes unstable. In this case, an invention for adding a low-temperature operation guarantee circuit (Patent Document 3) and an invention using a heater (Patent Document 4) have been proposed in order to prevent performance degradation of the cold cathode lamp at low temperatures. There is a problem that the structure is complicated and the cost is increased.

  In addition, when a cold cathode lamp is used as a light source to be mounted and replaced in a factory or a work place such as a liquid crystal display, the above mounting structure does not cause any inconvenience, but there are many on-site enforcement and replacement work. When a cold cathode lamp is used as a light source for an outdoor electric signboard, such a mounting structure causes inconvenience. In other words, the lamp cannot be mounted and replaced with one touch through soldering, and the work efficiency at the site is significantly impaired. Also, many cold cathode lamps are made of glass tubes with a diameter of less than 1 cm, and in the case of long lamps, sufficient care must be taken not to break them during installation and replacement work. The work efficiency was significantly impaired.

  The cold cathode lamp body of the present invention was created in order to solve the above problems, and a cold cathode lamp is secured by securing a gap between the inner peripheral wall of the lamp cover and the outer peripheral wall of the cold cathode lamp. In the cylindrical lamp cover and the lamp pins connected to the electrode wires of the lamp as lamp bodies protruding from the end members at both ends of the lamp cover, and the air in the gap in the lamp cover enclosing the cold cathode lamp And the inner diameter of the lamp cover with respect to the outer diameter of the lamp is set to such an extent that partial heat generation from the cold cathode lamp can be spread over the entire lamp by the heat medium.

  Therefore, according to the present invention, the surface temperature of the cold cathode lamp is obtained by using the air in the lamp cover enclosing the cold cathode lamp as a heat medium, and spreading the partial heat generation from the cold cathode lamp over the entire lamp by the heat medium. Therefore, even when the outside air temperature decreases, the surface temperature of the cold cathode lamp does not decrease in the same manner, and it is possible to prevent a decrease in performance.

  Hereinafter, specific embodiments of the present invention will be described with reference to the accompanying drawings. Reference numeral 1 in the figure denotes a lamp body of the present invention in which a cold cathode lamp 2 is enclosed in a lamp cover 8 (see FIG. 3). The lamp body 1 is assembled by inserting resin-made end members 3 and 3 into both ends of the lamp cover 8 while supporting the end portion of the cold cathode lamp 2 in the holding hole 4 via the support ring 5. . The end members 3 and 3 are provided with lamp pins 7 and 7 which are connected to the electrode wire 6 of the lamp. The lamp cover 8 of the lamp body 1 has a cylindrical shape made of glass or resin. When the cold cathode lamp 2 is sealed inside, a gap S is provided between the inner peripheral wall and the lamp outer peripheral wall (FIG. 6). reference).

  The gap S is for securing air between the lamp cover and the lamp outer peripheral wall. This air acts as a heat medium, and causes partial heat generation from the cold cathode lamp to spread over the entire lamp and raise the surface temperature of the cold cathode lamp to every corner. Therefore, even if the gap S is narrow and the amount of air is too small, conversely the gap S is wide and the amount of air is too large, it does not function as a heat medium. The dimensions of the cover inner diameter must be set. In this embodiment, the tube diameter is 10 to 13 mm (wall thickness is 0.7 to 1. mm) for a cold cathode lamp having an outer diameter of 3.0 to 4.5 mm, an overall length of 300 to 1500 mm, and a lamp current of 11.0 to 14.0 mA. The above action is realized by using a lamp cover made of polycarbonate or soda glass of 0 mm).

  FIG. 1 is an exploded perspective view of a cold cathode lamp body mounting structure according to the present invention, and FIG. 2 is a perspective view when the mounting is completed. Here, an outdoor electric signboard is assumed as a mounted device. Reference numeral 10 in the figure denotes a pair of sockets that clamp the lamp body 1 from both ends by contacting the end members 3 and 3 with the lamp pins 7 and 7 of the lamp body 1 inserted. The socket 10 has a socket cover 14 having a lamp pin insertion hole 16 in front of a cylindrical main body 11 in which a metal contact piece 12 to be contacted by the lamp pin 7 is received, and a port connected to the contact piece in the rear. The lead wire packing 13 for pulling out the lead wire 15 is press-fitted, and a hook-like stopper projection 17 for restricting movement in the axial direction with respect to the holder member 30 described later is provided on the outer periphery.

  In this embodiment, the lamp body 1 and the socket 10 are intended to have a waterproof structure, and a cylindrical waterproof packing 20 for the lamp body 1 and the socket 10 is fitted over the end of the lamp body 1 and the end of the socket 10. (See FIG. 4).

  The lamp body 1 and the socket 10 are fixed to the mounted device A via the holder member 30 (see FIGS. 5 and 6). The attached side device A shown in the figure is a light source mounting portion of an electric signboard. The holder member 30 made of an elastic material has a C-shaped holding arm 31 provided below, and a locking protrusion 32 for locking and fixing to an attachment hole A1 provided in the mounted device A. Is provided. The holding arm 31 has a shape in which the body of the lamp cover 8 of the lamp body and the body of the socket 10 can be inserted, and these are inserted by elastic deformation by press-fitting. Moreover, the latching protrusion 32 which provides a slit in the center as a deformation allowance passes through the mounting hole A1 of the attached side device A by elastic deformation by press-fitting.

  According to the mounting structure having the above configuration, first, both ends of the lamp body 1 are clamped by the sockets 10 and 10, and then inserted into the holder member 30 previously attached to the mounted side device to be held and fixed. Do. In this case, when the cold cathode lamp is long, in addition to the sockets 10 and 10 at both ends, the middle part of the lamp body 1 is held and fixed by the holder member 30. However, when the cold cathode lamp is relatively short, it is halfway. There may not be any holder member in place.

The cold cathode lamp body of the present invention was carried out with the following specifications, and a life test by continuous lighting was performed.
(1) Cold cathode lamp size / outer diameter 3.4mm, total length 1186mm
(2) Filled gas composition and filled gas pressure / Ar 5%: Ne 95%, 60 ^torr
(3) Lamp cover / Polycarbonate (UV cut), tube diameter 12mm, wall thickness 0.7mm
(3) Inverter / secondary negative voltage 1800V, oscillation frequency 52KHZ, lamp current 13.0mA

The following is a table showing the test results.
┌────────┬───┬────┬──────────────────┐
│ │ Atmosphere │ Case │ │
│ │Temperature │Internal temperature │ Result │
│ │ │ (℃) │ │
├────────┼───┼────┼──────────────────┤
│Comparison example (Single lamp │ │ │ (1) Flicker does not stop │
│Body) │ 0 │─── │ (2) Luminance decreases 10% in 2000 to 4000 hours│
├────────┼───┼────┼──────────────────┤
│Lamp of this device│-30│ 2.0│ (1) Flickering at start │
│ │ │ │ (2) Brightness decreases by 10% in 3000 to 6000 hours│
├────────┼───┼────┼──────────────────┤
│The lamp of this device│-10│17.0│28000 hours of normal lighting continues.
├────────┼───┼────┼──────────────────┤
│Lamp of this device│ 50│74.0│28000 hours of normal lighting continues│
└────────┴───┴────┴──────────────────┘

The disassembled perspective view of the mounting structure of the cold cathode lamp body of this invention. The perspective view at the time of mounting completion same as the above. FIG. 4 is a partially cutaway side view of the lamp body and the socket before providing waterproof packing. FIG. 4 is a partially cutaway side view of the lamp body and the socket. The side view of the principal part at the time of completion of mounting same as the above. Sectional drawing of the principal part at the time of completion of mounting same as the above.

Explanation of symbols

A Attached side device 1 Lamp body 2 Cold cathode lamp 3 End member 7 Lamp pin 8 Lamp cover 10 Socket 30 Holder member

Claims (2)

A gap is secured between the inner peripheral wall of the lamp cover and the outer peripheral wall of the cold cathode lamp so that the cold cathode lamp is accommodated in the cylindrical lamp cover and the lamp pins connected to the electrode wires of the lamp are connected to both ends of the lamp cover. The lamp body protruding from the end member of the lamp can be used as a heat medium for the air in the gap in the lamp cover enclosing the cold cathode lamp, and the partial heat generation from the cold cathode lamp can be spread over the entire lamp by the heat medium. A cold-cathode lamp body in which the dimension of the inner diameter of the lamp cover with respect to the outer diameter of the lamp is set as much as possible. A cold cathode lamp having an outer diameter of 3.0 to 4.5 mm, an overall length of 300 to 1500 mm, and a lamp current of 11.0 to 14.0 mA, a polycarbonate or soda glass having a tube diameter of 10 to 13 mm and a wall thickness of 0.7 to 1.0 mm. The cold cathode lamp body according to claim 1, which is housed in a lamp cover made of metal.

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