KR20020072335A - Method manufacturing frame of CRT - Google Patents

Abstract

PURPOSE: A frame of cathode ray tube and method for manufacturing the same is provided to remove howling phenomena by preventing external vibration or impact from being transferred to the shadow mask through the frame. CONSTITUTION: A cathode ray tube comprises a panel having a fluorescent screen formed at the inner surface of the panel; a shadow mask spaced apart from the fluorescent screen; a main frame where the shadow mask is fixed; a support frame having a sub frame fixed to the main frame; and a funnel fixed to the panel. The main frame is arranged such that the widthwise direction of the main frame is identical with the pressure direction of the material of the main frame. A method for manufacturing frame of CRT, comprises a first step of producing a main frame by performing a cold working process to a panel as a raw material for the main frame, blanking the cold worked panel into the length of the main frame, and bending the cut panel into an L-shape; a second step of producing a sub frame by cutting a square rod into a predetermined length and bending the cut rod to form an acute angle; and a third step of welding the sub frame to the main frame.

Description

Frame of cathode ray tube and its manufacturing method {Method manufacturing frame of CRT}

The present invention relates to a cathode ray tube, and more particularly, by cold working hot-rolled hot rolled sheet material, by cutting the cold plate material to be the width direction of the frame relative to the rolling direction to form a main frame The present invention relates to a frame and a manufacturing method of a cathode ray tube for preventing deformation of the mainframe.

1 is a cross-sectional view showing a conventional cathode ray tube, Figure 2 is a view showing a state in which the shadow mask assembly of the conventional cathode ray tube fixed to the panel, Figures 3a to 3c is a structure of the conventional cathode ray tube and the slot structure of the shadow mask Figure is shown. Figure 4 is a block diagram showing a frame manufacturing process of a conventional cathode ray tube.

As shown in the drawing, the conventional cathode ray tube includes a panel 10 having a phosphor 10a coated on its inner surface, a shadow mask assembly 20 installed inside the panel 10, and a rear of the panel 10. A funnel 12 to be coupled, an electron gun encapsulated at the rear of the funnel 12, and a deflection yoke 14 coupled to the rear periphery of the funnel 12 to deflect the electron beam emitted to the electron gun either horizontally or vertically. Doing.

And, behind the funnel 12, a magnet 16 of 2, 4, 6 poles is provided to correct the direction of movement so that the electron beam strikes the predetermined phosphor 10a applied to the inner surface of the panel 10. Prevents. In addition, since the panel 10 and the funnel 12 are coupled to the outer circumference of the skirt portion 10b of the panel 10 by a high vacuum, firecrackers may easily occur due to an external impact, thereby preventing a reinforcement band 17. ) Is installed.

As shown in FIG. 2, the shadow mask assembly 20 is fixed to the skirt portion 10b inside the panel 10 and is spaced apart from the phosphor 10a of the panel 10 at a predetermined interval. (21), a frame (22) to which the shadow mask (21) is tension-fixed, and a spring (23) fixed to the outside of the frame (22) and fixed to the stud pin (10c) of the panel (10); have.

Here, the cathode ray tube is required in each configuration and each part, specific conditions according to its driving, in particular, the electron beam emitted from the electron gun is a phosphor formed on the back of the panel 10 and the electron gun position relationship, as shown in FIG. The variation in grouping rate between the center and the peripheral portion of the panel 10 is deepened by the distance relationship and the deflection relationship up to 10a.

This grouping rate can be expressed by the following [Formula 1].

[Equation 1]

Beam brouping rate = (3 × S × Q) / (Pitch × L)

Grouping rate: three electron beam spacing (beam arrangement)

S: deflection yoke component (distance between red and green or distance between blue and green from the deflection center point of the electron beam)

Q: Distance from the shadow mask slot to the phosphor inside the panel

Pitch: Distance from the shadow mask slot center to the slot center

L: Distance from deflection yoke's electron beam deflection center to panel inner surface

In this case, when the distance between the shadow mask 21 and the inner surface of the panel 10 is large or small, the electron beam arrangement is unbalanced, which adversely affects color purity.

In addition, electrons radiated from the electron gun strike the shadow mask 21 and turn into thermal energy, causing a domming phenomenon in which the shadow mask 21 is expanded. In addition, the frame 22 is thermally expanded to move the position of the slot through which one electron beam passes in the shadow mask 21. Then, the vibration is transmitted to the frame 22 through the stud pin 10c attached to the panel 10 by the vibration or shock transmitted from the outside of the cathode ray tube, causing a tremor phenomenon, this tremor is transmitted to the shadow mask 21 The screen shakes, that is, howling.

As such, the frame 22 fixing the shadow mask 21 plays a very important role. The structure of the frame and the raw materials of the frame are shown in FIGS. 4A to 4C.

As shown in FIG. 4A, the frame 22 includes a pair of main frames 22a to which the shadow mask 21 is tension-fixed in the long axis direction of the panel 10, and subs fixed to both ends of the main frame 22a. Frame 22b. In addition, the main frame 22a is formed of a hot rolled sheet material having a cross section having an approximately "L" shape, and the subframe 22b is formed of a square bar material having a square shape.

In particular, the main frame 22a, to which the shadow mask 21 is fixed, is cut and formed so that its longitudinal direction coincides with the rolling direction of the raw material 30, as shown in FIG. 4B.

The manufacturing process of such a frame 22 will be described in more detail with reference to FIG. 5 as follows.

First, the manufacturing process of the main frame 22a, the hot rolled sheet material, that is, the raw material 30 is cut to a certain length by a blanking operation so that the rolling direction is the longitudinal direction of the main frame 22a (S01), The cut material is bent in an L shape (S02).

Then, the subframe 22b first cuts the rectangular bar material to a predetermined length (S03), and then bends the cut rectangular bar material to form an acute angle (S04).

As described above, the frame 22 is completed by welding fixing (S05) a pair of subframes 22b having acute angles formed at both ends of the pair of L-shaped main frames 22a.

When the frame 22 is completed as described above, the frame 22 is compressed in the long axis direction, that is, in the main frame 22a direction, and then the edge of the shadow mask 21 is welded and fixed to the upper end of the main frame 22a. Then, the shadow mask 21 is cut and the compressive load applied to the main frame 22a is removed. Then, the shadow mask 21 is fixed in the tensioned state to the main frame 22a.

As described above, in the frame 22 in which the shadow mask 21 is tensioned uniaxially, the compressive force applied to the frame 22 is applied to the shadow mask 21 and the strength of the frame 22 is determined. The strength of the frame 22 and the tensile force of the shadow mask 21 play an important role in determining the characteristics and quality of the cathode ray tube.

In addition, the compressive load applied to the frame 22 depends on the material strength characteristics of the frame 22, and the compressive load does not exceed the yield strength of the main frame raw material 30 of the frame 22. Since it is possible to apply to the frame only within, this compressive load is ultimately determined by the yield strength of the mainframe raw material 30.

However, since the main frame 22a of the conventional cathode ray tube is formed by blanking a hot rolled sheet material and bending the letter L, as shown in FIG. 5, in order to attach the shadow mask 21 to the main frame 22a, FIG. As described above, when a predetermined compressive load is applied to the frame 22, the main frame 22a has a desired yield strength at the center portion, as shown in Table 1 below. The problem of not applying the tension occurs.

In order to solve the above problems, the thickness of the main frame 22a may be increased in order to reduce the stress generated by the compressive load. However, when the thickness of the main frame 22a is increased, the manufacturing cost increases. In addition, the vibration characteristics of the frame 22 are deteriorated, which causes a problem that the howling characteristics are deteriorated.

Therefore, the present invention has been made in order to solve the above problems, and after cold working the hot rolled sheet material, blanking so that the rolling direction of the cold-worked raw material becomes the width direction of the main frame to form the main frame, It is an object of the present invention to provide a frame of a cathode ray tube and a method of manufacturing the same, in which a high yield strength is obtained and a tension required for a shadow mask is applied.

1 is a cross-sectional view showing a conventional cathode ray tube,

2 is a view showing a state in which a shadow mask assembly of a conventional cathode ray tube is fixed to a panel;

3a to 3c is a view showing the structure of the conventional cathode ray tube and the slot structure of the shadow mask,

Figure 4 is a perspective view showing the raw material of the main frame and the main frame of the conventional cathode ray tube,

5 is a block diagram showing a frame manufacturing process of a conventional cathode ray tube;

Figure 6 is a block diagram showing a frame manufacturing process of the cathode ray tube according to the present invention,

7 is a view showing a raw material forming the main frame of the cathode ray tube according to the present invention,

8 is a perspective view showing a state in which the compression load is applied to the frame of the cathode ray tube according to the present invention;

9 is a graph showing the results of the raw material strength test for forming the main frame of the cathode ray tube according to the present invention.

The support frame of the cathode ray tube according to the present invention for achieving the above object, the panel is formed with a fluorescent surface on the inner surface; A shadow mask spaced apart from the fluorescent surface at a predetermined interval; A support frame having a main frame to which the shadow mask is fixed and a subframe fixed to the main frame; In the color cathode ray tube comprising a funnel fixed to the panel, the main frame is characterized in that the width direction is formed to match the pressure direction of the raw material of the main frame.

In addition, the manufacturing method of the support frame of the cathode ray tube according to the present invention for achieving the above object, the step of cold working the hot rolled sheet material which is the raw material of the main frame, the step of testing the strength of the cold processed raw material, Determining a blanking direction for blanking the raw materials according to the results of the strength test, blanking the cold worked cold rolled sheet to the length of the mainframe, and bending the cut material to an L-shaped mainframe A first process of manufacturing a second process, a second process of manufacturing a subframe by cutting the rectangular bar material to a predetermined length and bending the cut rectangular bar material to form an acute portion, and a third process of welding the subframe to the main frame. Characterized in that it comprises a.

Hereinafter, the configuration and operation of the frame manufacturing method of the cathode ray tube according to the present invention will be described in more detail.

6 is a perspective view showing a state in which a compression load is applied to the frame of a typical cathode ray tube, Figure 7 is a block diagram showing a frame manufacturing process of the cathode ray tube in the present invention. 8 is a perspective view showing a main frame of a cathode ray tube and a raw material thereof according to the present invention, and FIG. 9 is a view showing a state in which a compressive load is applied to a frame in comparison with the present invention.

As shown, the cathode ray tube according to the present invention is a panel in which a fluorescent surface is formed on an inner surface, a shadow mask installed spaced apart from the fluorescent surface at a predetermined interval, a support frame to which the shadow mask is fixed and fixed, the rear of the panel It contains a funnel that is fixed to it.

The support frame is fixed to a skirt formed at the edge of the panel, and comprises a pair of mainframes to which the shadow mask is fixed and subframes fixed to both ends of the mainframe.

The main frame is subjected to cold rolling of a hot rolled sheet material, which is a raw material, and subjected to a strength test, and then a blanking process is determined by blanking in a direction of high strength. The blanking is then L-shaped to complete the mainframe.

On the other hand, when the main frame is formed by blanking, the main frame is formed by blanking the raw material so that the rolling direction of the raw material becomes the width direction of the main frame.

Here, the method of manufacturing the main frame will be briefly described with reference to FIG. 7.

As shown, the manufacturing method of the support frame according to the present invention comprises the steps of cold working the hot rolled sheet material, the raw material of the main frame, testing the strength of the cold worked raw material, and the raw material according to the results of the strength test Determining a blanking direction for the blanking process, blanking the cold worked cold rolled sheet material to the length of the main frame, and bending the cut material to an L-shape.

On the other hand, the method of manufacturing the subframe is the same as the conventional method will be omitted here.

The main frame is completed by welding and fixing subframes at both ends of the main frame manufactured as described above.

Here, the strength test of the raw material, first, when the rolling direction of the raw material is the same as the longitudinal direction as shown in Fig. 8, after the yield test is tested to match the rolling direction and the longitudinal direction of the main frame, The yield test is carried out so that the rolling direction shown in 8 and the width of the main frame coincide with each other. Then, even when the rolling direction of the raw material is the same as the width direction of the raw material, the strength test of the raw material is conducted in the same manner as described above.

When the strength test of the raw material is completed, the blanking direction of the raw material is determined based on the experimental data of the strength test.

On the other hand, the raw material strength test of the mainframe has a very deep relationship with the rolling direction of the raw material and the strength of the mainframe, which is the same as the rolling direction of the raw material and the longitudinal direction of the mainframe, and the rolling direction of the raw material and the width of the mainframe. In the case of the same direction as in Fig. 6, when the compressive load is applied in the main frame direction of the frame, and the stress magnitude generated in the three directions of the central part of the main frame is measured, the rolling direction of the raw material and the width direction of the main frame When the average value of the yield strength of the 100%, the relationship is as shown in Table 1 and Figure 9 below.

TABLE 1

Same as the rolling direction of raw materials and the longitudinal direction of the mainframe Same as rolling direction of raw material and width direction of main frame NO The tensile strength Yield strength The tensile strength Yield strength (end) (I) (All) (la) σ1 87.83% 71.51% 104.49% 100.90% σ2 87.50% 74.06% 104.75% 99.21% σ3 85.04% 74.06% 104.69% 99.90% Average 86.79% 74.33% 104.64% 100.00%

That is, as shown in the above table, since the strength difference of the raw material is generated according to the rolling direction of the raw material, when blanking to form the main frame, the same as the rolling direction of the raw material and the longitudinal direction of the main frame, that is, than the conventional It can be seen that the case where the raw material is the same as the rolling direction of the raw material and the width direction of the main frame, that is, the present invention, can secure about 26% more strength of the raw material.

As described above, according to the present invention, by cold-processing the raw material of the main frame, blanking and bending to match the rolling direction of the raw material and the width direction of the main frame to form a main frame, the material of the same thickness is higher Yield strength can be obtained, thereby applying a higher compressive load to the frame and imparting the required tensile force to the shadow mask attached to the mainframe.

In addition, as the tensile force required for the shadow mask is applied, it is possible to reduce transmission of external vibrations or shocks to the shadow mask through the frame, thereby improving screen shaking, that is, howling characteristics.

Claims (3)

A panel having a fluorescent surface formed on an inner surface thereof; A shadow mask spaced apart from the fluorescent surface at a predetermined interval; A support frame having a main frame to which the shadow mask is fixed and a subframe fixed to the main frame; In the color cathode ray tube comprising a funnel fixed to the panel, The main frame is a support frame of a color cathode ray tube, characterized in that the width direction is formed to match the pressure direction of the raw material of the main frame. Cold working the hot rolled sheet material, which is the raw material of the main frame, blanking the cold worked cold rolled sheet material to the length of the main frame, and bending the cut material to an L shape to manufacture the main frame. and, A second process of manufacturing the subframe by cutting the rectangular bar material to a predetermined length and bending the cut rectangular bar material to form an acute part; And a third process of welding the subframe to the main frame. The method for manufacturing a frame of a cathode ray tube according to claim 2, wherein the blanking direction is such that the rolling direction of the raw material coincides with the width direction of the main frame.