JP2640907B2 - Manufacturing method of explosion-proof band for CRT - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for manufacturing an explosion-proof band for a cathode ray tube.

[0002]

2. Description of the Related Art As is well known, in a cathode ray tube, an outer periphery of an end portion on a display surface side is tightened with an explosion-proof band. This explosion-proof band is formed by joining both ends of a plated band-shaped metal plate, for example, a steel plate, and then overhanging it so as to conform to the shape of a CRT.

FIGS. 7 and 8 show explosion-proof bands manufactured by a conventional method. Reference numeral 1 denotes a band-shaped metal plate, for example, a steel plate. Reference numeral 4 denotes the weld.
After that, the band main body 5 is formed by overhanging to conform to the shape of the cathode ray tube. An ear 6 is joined to the outer periphery of each corner by welding to form an explosion-proof band.

However, according to the method of forming the band main body 4 by joining both ends 2 and 3 of the steel plate 1 by spot welding, the welded portion may be deteriorated and rust may be generated.
Further, since the joining strength by spot welding is weak, it is necessary to perform spot welding at a plurality of places, and the operation is troublesome, and the spot welding equipment and its cost are expensive.

[0005]

SUMMARY OF THE INVENTION An object of the present invention is to provide a method of forming a band body by joining both ends of a strip-shaped steel sheet by mechanically caulking without using spot welding. And

[0006]

The present invention SUMMARY OF] prepares a punch having a cylindrical punch section, the dialog with the periphery to the ring groove of the bottom surface of the die portion and the die portion punch unit is fitted,
Lay both ends of the strip-shaped metal plate between the punch and the die
Before being placed together with the punch and the die part
Place the metal plate on the punch and die
More drawing and the punch side in the die part
The metal plate located at
It is characterized in that both ends of the metal plate are joined .

[0007]

When crimping with a crimping tool, the both ends that are first overlapped are pushed into the die by the punch portion and are deep-drawn. Here, when a pressing force is further applied by the punch, both end portions are forcibly pushed into the ring groove of the die portion, and required crimping is performed. As a result, both ends are firmly joined.

[0008]

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 7 and 8 denote the same or corresponding parts. 1 to 4, reference numeral 7 denotes a caulking tool used in the present invention. This is composed of a punch 9 having a cylindrical punch portion 8 at the tip and a die 11 having a die portion 10 into which the punch portion 8 fits. A ring groove 12 is formed on the periphery of the bottom surface of the die portion 10. It has been formed.

First, as shown in FIG. 1, a portion where both ends 2 and 3 of a metal plate 1 are overlapped is placed on the surface of a die portion 11, and then a punch 9 is pressure-bonded to the die 11 as shown in FIG. Let it. As a result, the punch portion 8 pushes both ends 2 and 3 into the die portion 10, and a part of the end portion 3 on the die 11 side is forcibly pushed into the ring groove 12, whereby deep drawing is performed. .

Here, when the pressing force of the punch 9 is further applied,
As shown in FIG. 3, the end 2 on the side of the punch 9 spreads out inside the die 10, where caulking is performed. Thereafter, when the punch 9 is pulled up, both ends 2, 3 are caulked as shown in FIG. Reference numeral 13 in FIGS. 5 and 6 denotes a caulked portion caulked as described above. The subsequent manufacturing process is the same as the conventional one.

[0011] As will be understood from the foregoing description, in the caulking portion 13 of the end portions 2 and 3, the end portion 2 toward the end portion 3
Because it is caulked so as to spread the entire outer circumference substantially uniformly I or, shear strength, is performed interlocks required peel strength, the bonding strength is extremely large. Therefore, the caulking portion 13 does not require a large number as in the case of spot welding.

Further, since the joining is not performed by welding, there is no occurrence of deterioration and rust at the joining portion. Further, the work is easier than in the case of using a welding device, no welding equipment is required, and the construction cost is low.

[0013]

According to the present invention described above, according to the present invention, Ri per to produce cathode ray tubes of explosion-proof band by caulking tool punch with a peripheral edge ring groove of the bottom surface of the die to be fitted, the band Since the metal plate is joined by caulking both ends , sharp edges or
No burrs and directional shear strength / peel strength
Not high bonding is obtained. As a result, the joints deteriorate and rust
There is no occurrence and it is enough for shrink fitting to CRT
A stable joining force can be obtained. In addition, the number of joining
This is advantageous in that an explosion-proof band can be easily and inexpensively manufactured.

[Brief description of the drawings]

FIG. 1 is a partial cross-sectional view showing an initial position of a process according to an embodiment of the present invention.

FIG. 2 is a partial sectional view showing a deep drawing step.

FIG. 3 is a partial cross-sectional view showing a caulking step.

FIG. 4 is a partial cross-sectional view showing a completed state of the bonding.

FIG. 5 is a front view of an explosion-proof band manufactured according to the present invention.

6 is a plan view of the explosion-proof band of FIG.

FIG. 7 is a front view of an explosion-proof band manufactured by a conventional method.

FIG. 8 is a plan view of the explosion-proof band of FIG.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Metal plate 2 End part 3 End part 5 Band main body 7 Caulking tool 8 Punch part 9 Punch 10 Die part 11 Die 12 Ring groove 13 Caulking part

Claims (1)

(57) [Claims] 1. A punch having a cylindrical punch portion, a die portion into which the punch portion is fitted, and a periphery of a bottom surface of the die portion.
Providing a dialog with a ring groove on the edge, the said punch
Lay both ends of the strip-shaped metal plate between the dies,
Lamination of the punch and the metal plate located on the die portion
Draw a part by using the punch and the die
And a metal plate located on the punch side in the die portion
Is spread outward and crimped to connect both ends of the metal plate.
A method for manufacturing an explosion-proof band for a CRT , wherein the joined band-shaped metal plate is used as a band main body of the explosion-proof band.