JP2594210B2 - Tube type small light bulb - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an ultra-small tube-type compact electric bulb which is incorporated in an electronic device and shines a digital display or the like.

2. Description of the Related Art Conventionally, this kind of bulb has a total length of 3 to 10 m.
m, a very small tube-shaped bulb with a diameter of 0.5 to 2 mm. As the shape, there are a shape of a lead wire protruding from both ends of the glass tube, and a shape with a micro cap at both ends of the glass tube.

When such a micro tube lamp is mounted on a substrate, the lead wire protruding from both ends of the glass tube must be inserted into a hole provided in the substrate. Although the wire was inserted and the back side was soldered and attached, the insert machine was not available and it depended on manual labor. In addition, in the case of a glass tube having a micro-base at both ends, the adhesive between the lamp and the micro-base was peeled off at the mounting temperature at the time of surface mounting, or the lamp was not lit.

Therefore, it is necessary to attach bases to both ends of the lamp for surface mounting using an insert machine. However, since the lamp is a microminiature bulb, an adhesive is applied to the base. At present, the work and the work of soldering the lead wire and the base are not easy and require a lot of manpower and time. The present invention has been developed as a result of intensive research in order to save such labor, and uses a close-wound spring instead of the conventional base, and utilizes the elastic pressure of this spring to make use of the elastic pressure of both ends of the glass tube. And further,
Conduction and fixing are performed by inserting and holding a lead wire between tightly wound springs. Thus, the springs at both ends serve as a base, and have the function of a tube lamp with a base.

Therefore, molding is performed without using an adhesive for fixing the bases to both ends of the glass tube, and even in the case of soldering, it is easier than conventional soldering. Surface mounting is now possible in which a tube lamp with a base formed on the surface of a substrate is fixed and mounted with solder paste.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a side view of an enlarged bulb according to the present invention, and FIG. 2 is a sectional view of the same. FIG.
Shows an enlarged explanatory view of the tube end of the light bulb. FIG. 4 is an enlarged side view of the light bulb according to claim 2, FIG. 5 is a sectional view of the same, and FIG. 6 is an enlarged explanatory view of a tube end of the light bulb. In the figure, (1) is a glass tube,
(4) shows a lead wire, this lead wire (4) is opposed, and the filament (3) is connected. Reference numeral (4-2) in the figure denotes a connecting portion between the lead wire (4) and the filament (3). Naturally, both ends of the glass tube (1) are sealed. Both ends of the lead wire (4) are bent as shown in the drawing and cut out so as to project outward. Since the cut portion (4-1) of the lead wire is clamped and fixed by the close-wound spring (2), the cut portion (4-1) of the lead wire is exposed to the outside. The above is the light bulb according to claim 1 shown in FIGS. 1 to 3, and the tube end can be subjected to soldering as shown in FIGS. Reference numeral (5) in the drawing denotes solder for fixing the end face, and (6) denotes solder for fixing the spring by elution of the solder on the end face.

As described above, in the tube-type small light bulb of the present invention, an adhesive for fixing the base is not required by using the close-wound spring (2) instead of the conventional base, and the pressure of the spring is reduced. The end (4-1) of the lead wire can be exposed and fixed. For this reason, when mounting on a substrate, surface mounting can be performed simply by placing the substrate on the surface of the substrate via an adhesive, and the operation of forming the substrate has become extremely easy.

[Brief description of the drawings]

FIG. 1 is a side view showing the entirety of a small tubular light bulb of the present invention.

FIG. 2 is a sectional view of FIG.

FIG. 3 is an enlarged sectional view of a main part.

FIG. 4 is a side view showing another embodiment of the present invention.

FIG. 5 is a sectional view of FIG. 4;

FIG. 6 is an enlarged sectional view showing a main part of FIG. 4;

[Explanation of symbols]

 (1) Glass tube (2) Closely wound spring (3) Filament (4) Lead wire (5) Solder at tube end

Claims (2)

(57) [Claims] 1. A method of connecting a filament between two opposing leads. B. Sealing the lead wire in a glass tube and sealing both ends of the glass tube. C. Lead wires protruding from both ends must be bent outward to protrude. D Cover both ends of the glass tube with tightly wound springs and fix them so that the protruding lead wires are sandwiched. A small tube-shaped light bulb satisfying the above requirements A to D. 2. A method of connecting a filament between two opposing leads. B. Inserting the lead wire into a glass tube to seal both ends of the glass tube. C. Lead wires protruding from both ends must be bent outward to protrude. D. Fix both ends of the glass tube so that the protruding lead wires are clamped by tightly wound springs. E Finish both ends of the glass tube and the spring by soldering. A small tube-shaped light bulb having the above-mentioned A to E requirements.