JPH0434835A - Fluorescent lamp - Google Patents

Abstract

PURPOSE:To improve the efficiency of sealing work with a glass member melted and sealed by sticking the part of a glass member fast to the bending part of a tubular metal member, and applying a high-frequency magnetic field to make induction heating. CONSTITUTION:The lower bottom part 1c of an envelope 1 is formed on a bending part (c) bent almost right angle to the axis line of the envelope 1. Also a high-frequency magnetic field is applied to the bottom part 1c of the envelope 1 and each bottom part of upper and lower part different-level parts 1a and 1b from their vertical direction. This causes an eddy current to be most effectively generated in each bending part, having a vertical direction to the application direction of the magnetic field, to induction-heating each bending part, and each closely fitted part of a translucent plate 11, glass beads 10, and a glass stem 3 sticked fast respectively is heated to be melted, and then is deposited in each bending part (a, b, and c) to be airtightly sealed. Consequently the sealing of plural places can be made at a time without using adhesive such as frit glass to improve the workability of the assembly work of a fluorescent lamp.

Description

[Detailed Description of the Invention] [Object of the Invention] (Industrial Application Field) The present invention relates to a fluorescent lamp suitable for use as a display element, such as an electronic display panel, or a light-receiving element for decorative lighting. In particular, the present invention relates to a fluorescent lamp in which the method for sealing glass members is simplified.

(Prior Art) In general, display fluorescent lamps suitable for electronic display panels include single-tube monochromatic or single-tube multicolor fluorescent lamps. That-
For example, a cathode and a plurality of anodes are placed facing each other and housed in an envelope made of metal such as stainless steel and formed into a cylindrical shape with a bottom, and the open end of the envelope on the anode side is In some cases, the display surface is hermetically sealed by a transparent plate that forms the display surface, and the open end on the cathode side is hermetically sealed by a glass stem in which the cathode is installed.

Further, in the axially intermediate portion of the envelope, pin-shaped lead wires electrically connected to each anode are hermetically penetrated and extended to the outside.

(Problem to be Solved by the Invention) However, in such a fluorescent lamp, the transparent plate, the glass stem, and the penetration portion through which each lead wire passes are sealed to the envelope with an adhesive such as frit glass. Therefore, it is necessary to add frit glass or the like to each of these sealing parts, and the addition work is complicated, resulting in a problem that the efficiency of assembling the fluorescent lamp is low.

Moreover, if the amount of frit glass added is excessive, for example, the outer peripheral edge of the transparent plate that forms the display surface may be slightly covered by the frit glass, and in this case, the display area may be reduced. Another problem is that of changing the display planar shape.

Therefore, the present invention has been made in consideration of the above circumstances, and
The purpose is to provide a fluorescent lamp that can melt and seal glass members without using an adhesive such as frit glass and improve the efficiency of the sealing work.

[Structure of the invention]

(Means for Solving the Problems) The present invention locally heats the bent portion of a cylindrical metal member by high-frequency induction heating to locally heat and melt the contact portion of the glass member that is in close contact with the bent portion. It is melted and fusion-sealed to the bent part, omitting the use of adhesives such as frit glass, and is constructed as follows.

That is, the present invention provides a fluorescent lamp having a sealing part for sealing a glass member to a cylindrical metal member, in which the sealing part bends a part of the cylindrical metal member in a direction perpendicular to its axis, and A part of the glass member is brought into close contact with the bent portion, a high frequency magnetic field is applied from a direction substantially perpendicular to the bent portion, and the bent portion is heated by induction, thereby melting and sealing the sealed portion of the glass member. It is characterized by

(Function) A high-frequency magnetic field is applied to the cylindrical metal member from a direction perpendicular to the bent portion that is bent in the direction perpendicular to its axis.

Therefore, the bent part of the cylindrical metal member that is almost perpendicular to this high-frequency magnetic field is most efficiently heated by induction, and the temperature becomes higher than other parts, so the part of the glass member that is in close contact with this bent part is heated. It is melted and sealed.

Therefore, according to the present invention, it is possible to seal the glass member to the cylindrical metal member without using an adhesive such as frit glass, so that the process of adding glass frit etc. can be omitted. It is possible to improve the efficiency of assembling the fluorescent lamp.

In addition, while efficiently heating the bent portion of the cylindrical metal member,
Since non-sealed parts other than bent parts that are not perpendicular to the high-frequency magnetic field are not heated by induction with high efficiency, it is possible to prevent sealing and thermal deformation of these unsealed parts, and also to generate a high-frequency magnetic field. Power consumption can be prevented.

Further, even if the cylindrical metal member has a plurality of bent portions, the glass members can be sealed almost simultaneously by applying a high-frequency magnetic field once, and the efficiency of the sealing work is improved.

(Example) An example of the present invention will be described below based on FIGS. 1 to 4.

Figure 2 is an external perspective view of an embodiment of the present invention, Figure 3 (A)
is the mA arrow view in Figure 2, and Figure 3 (B) is m in the same figure (A).
A sectional view taken along the line B-mB, and FIG. 4 is an exploded perspective view of FIG. 2.

In these figures, the envelope 1 is formed of a thin metal plate such as stainless steel or iron into a cylindrical shape with a bottom, for example by drawing, with one axial end (upper end in Figure 4) open. There is.

As shown in FIGS. 3(B) and 4, the upper part of the envelope 1 is formed by sequentially widening the upper part 1a in a rectangular tube shape in two steps in the vertical direction. A lower step portion 1b having a slightly smaller diameter is formed respectively.

Therefore, the bottoms of the upper and lower step portions 1a and lb are respectively formed into bent portions a and b bent in a direction substantially perpendicular to the axis of the envelope 1.

The entire inner peripheral surface from the lower end of the lower step 1b to the lower bottom 1c of the envelope 1 is coated with a glass film (not shown), so that when a discharge occurs in the envelope 1, The internal impurity gas is released from the metal envelope 1,
This is prevented by the glass coating and increases the strength against external pressure.

In addition, a center hole 1d is bored in the lower bottom IC of the envelope 1, and the lower bottom IC is formed in a bent portion C bent in a direction substantially perpendicular to the axis of the envelope 1. There is.

A glass stem 3 having a cathode 2 erected thereon is fused and fixed on this bent portion C by high-frequency induction heating, which will be described later.

The cathode 2 has a pair of lead wires 2a supporting both ends thereof,
The tip of the glass stem 3 is passed through the glass stem 3 in the plate direction and electrically connected to a lighting circuit (not shown).

In addition, a glass exhaust pipe 4 is integrally protruded from the lower opening periphery of the center hole 3a of the glass stem 3, and the glass stem 3 is airtightly fitted into the bottom IC of the envelope 1. As shown in FIG. 3(B), the tip of the exhaust pipe 4 extends outward from the center hole 1d of the bottom IC of the envelope 1.

A tapered tube 5 is inserted downward into the envelope 1 and fixed. A cross-shaped partition plate 6 is coaxially fitted into the tapered tube 5, and a second Figures and Figure 3 (
As shown in A), for example, there are four light-emitting chambers 7a, 7b, and 7c each having a rectangular plan view.

Each room is divided into 7d sections.

For example, as shown in FIG. 2, the inner surface of the tapered tube 5 facing the light emitting chambers 7a to 7d and the outer surface of the partition plate 6 are coated with green (G) and blue (B) for each of the light emitting chambers 7a to 7d. ), green (G
) and red (R), respectively, are covered with fluorescent films 8 that emit light.

The tapered cylinder 5 has, for example, circular discharge holes 5a to 5d at its bottom.
is opened for each light emitting chamber 7a to 7d.

For example, four anodes 9a are provided in each light emitting chamber 7a to 7d.
The anodes 9b, 9c, and 9d are housed in the lower step 1b of the envelope 1, and the lower ends of the anodes 9a to 9d are connected to the lead wires 9, respectively.

The tip of each lead wire 9 passes through the spherical glass beads 10, vertically and airtightly through the bottom of the lower step 1b, and extends to the outside to be electrically connected to a lighting circuit (not shown). It has become.

Each glass bead 10 is positioned by fitting its lower hemisphere into a hemispherical recess 1e at the inner bottom of the lower step 1b.

Further, a light-transmitting plate 11 made of transparent plate glass is fitted into the upper step portion 1a of the envelope 1.
The outer surface of is set as the display surface.

Then, high-frequency waves are applied to each of the bent portions a, b, and c, that is, the bottom IC of the envelope 1 and the bottoms of the upper and lower step portions 1a and lb, from the vertical direction, that is, one of the axial directions of the envelope 1. Apply a magnetic field.

Then, eddy currents are most efficiently generated in the bent parts a, b, and c, which are perpendicular to the direction of application of the high-frequency magnetic field, that is, the bottom parts of the sealed part, and these parts are heated by high-frequency induction. Each bend a, b.

The transparent plate 11, the glass beads 10, and the glass stem 3 are heated and melted, and are welded to the bent portions a, b, and c, respectively, and hermetically sealed.

Therefore, according to this embodiment, each glass member of the glass stem 3, the glass beads 10, and the transparent plate 11 can be attached to the bottom 1c of the envelope 1 without using an adhesive such as frit glass.
, the upper and lower step portions 1a and lb, respectively, and by applying a high frequency magnetic field once from the axial direction of the envelope 1, the glass stem 3, the glass beads 10, and the transparent plate can be sealed. 11 can be sealed at almost the same time, the efficiency of the sealing work can be improved.

In addition, since the unsealed parts other than the bent parts a to c of the envelope 1, which are the sealed parts, are almost parallel to the high-frequency magnetic field or at a required angle, the generation efficiency of eddy current is low, and the high-frequency induction Since it is difficult to be heated, it is possible to prevent the unsealed portion from being sealed, and also to prevent thermal deformation and the like, and to prevent waste of high frequency power.

〔Effect of the invention〕

As explained above, the present invention bends the sealing part of a cylindrical metal member that seals a glass member in a direction perpendicular to the axis of the cylindrical metal member, and also includes a part of the glass member in this bent part. are in close contact with each other and a high-frequency magnetic field is applied from a direction almost perpendicular to this bent part, so that while the bent part that is almost perpendicular to this high-frequency magnetic field is efficiently induction heated, the bent part that is almost parallel to or almost perpendicular to this high-frequency magnetic field is heated by induction. Induction heating in the non-sealed portion forming the required angle can be reduced.

Therefore, according to this embodiment, the bent portion of the cylindrical metal member can be locally induction heated to a high temperature to melt and seal the glass member, and the non-sealed portion other than the bent portion can be heated. Therefore, it is possible to prevent sealing and heat deformation in the non-sealed portion, and also to prevent waste of high frequency power.

According to the present invention, it is possible to seal a glass member to a cylindrical metal member without using an adhesive such as frit glass, so it is possible to omit steps such as adding an adhesive to the sealed part. In addition, it is possible to seal a plurality of locations almost at once by applying a vague high-frequency magnetic field, thereby improving workability in assembling the fluorescent lamp.

[Brief explanation of the drawing]

FIG. 1 is an enlarged view of the main part of FIG. 3(B), FIG. 2 is an external perspective view of an embodiment of the fluorescent lamp according to the present invention, and FIG. 3(A)
is I[[A arrow view in Figure 2, Figure 3 (B) is the same figure (A)
4 is an exploded perspective view of FIG. 2. DESCRIPTION OF SYMBOLS 1... Envelope (cylindrical metal member), 1a... Upper step part, 1b... Lower step part, IC... Lower bottom part, 3... Glass stem, 10... Glass beads , 11...Transparent plate, a, b, c...Bending portion.

Claims (1)

[Claims] In a fluorescent lamp having a sealing part that seals a glass member to a cylindrical metal member, the sealing part bends a part of the cylindrical metal member in a direction perpendicular to its axis, and the glass member is attached to the bent part. A part of the glass member is brought into close contact with the glass member, a high frequency magnetic field is applied from a direction substantially perpendicular to the bent part, and the bent part is heated by induction, thereby melting and sealing the sealed part of the glass member. lamp.