KR20010021327A - Frame of CRT - Google Patents

Abstract

PURPOSE: A frame for a color cathode-ray tube is provided to improve impact and vibration characteristic of the color cathode-ray tube by forming a shape of beads intensity is improved on four corners of the frame. CONSTITUTION: The frame for a color cathode-ray tube has a frame structure having a square shape, an inrush grooves having a bead shape with a radius and double beads having shape of stair with over two steps. The grooves is formed at the outside corner portions of the frame at which a long side axis and a short side axis of the frame are met each other. The double beads are formed on the each inrush groove. Assume that total bead length at the long side axis is 1, bead length of two levels at the long side axis is 2, total bead depth at the short side axis is 1, bead depth of two levels at the short side axis is 2 and radius is R, relationship among 1, 2, 1, 2 and R satisfies an equation 0.1 1 2 £ 1-( 1+ 2)-R|. A ratio of 2 to 1 is 0.1<( 1/ 2)<0.8. Assume that total bead length at the short side axis is 1, bead length of two levels at the short side axis is 2, a ratio of 2 to 1 satisfies an equation 0.1<( 2/ 1)<0.8. Assume that total bead depth at the long side axis is 1, bead depth of two levels at the long side axis is 2, a ratio of 2 to 1 satisfies an equation 0.1<( 2/ 1)<0.8. Assume that total bead height at the short side axis is h1, bead length of two levels at the short side axis is h2, a ratio of h2 to h1 satisfies an equation 0.2<(h2/h1)<0.65.

Description

Frame for color cathode ray tube {Frame of CRT}

The present invention relates to a color cathode ray tube, and more particularly, to a frame for improving rigidity at a corner part by improving a bead shape of a frame, which is a component for improving drop impact and vibration characteristics.

In general, the frame supporting the shadow mask in the cathode ray tube is a component having a characteristic that the higher the rigidity is, the better the impact and vibration resistance characteristics are. Therefore, various methods have been proposed to increase the rigidity of the frame. The simplest method is to increase the thickness, but this is unsuitable in terms of production efficiency because it increases the cost of the parts.

The most commonly used method is to increase the stiffness by inserting an inrush groove, that is, a bead in a proper position of the frame. In the method of giving beads, first, the stiffening beads are placed in the most stressed part when vibration displacement or shock displacement occurs. In the case of the cathode ray tube frame, most of the vibration displacement and impact displacement show that the stress is largely stressed at the corner portion, which confirms that the corner portion of the frame determines the rigidity of the frame.

Hereinafter, an example of a color cathode ray tube equipped with a frame according to the prior art will be described with reference to FIGS. 1 and 2.

1 is a partial cutaway view of a typical cathode ray tube, and FIG. 2 is an exploded perspective view of a front panel side component of the cathode ray tube.

The illustrated color cathode ray tube is made of a front panel (1) and a funnel-shaped funnel (2) fused to the rear end of the panel (1) to form a vacuum outer container, the end of the small diameter of the funnel (2), In other words, an electron gun 3 radiating the electron beam 10 is enclosed in the neck 12, and a deflection yoke 8 is mounted on the outer diameter to deflect the emitted electron beam 10 to the entire screen.

In addition, red (R), green (G), and blue (B) fluorescent films 1a are formed on the inner surface of the panel 1, and are separated from the fluorescent film 4 by a predetermined distance to perform color screening functions. The shadow mask 5 is supported by the frame 6, the frame 6 is supported inside the panel 1 by the spring 4, and the deflected electron beam 10 is blocked at the rear end side by the external magnetic field. Inner shield 11 is coupled to.

In this state, the three R / G / B electron beams 10 emitted from the electron gun 3 are deflected to a desired portion of the screen by the vertical and horizontal deflection magnetic fields of the deflection yoke 8, and the shadow mask 5 While passing through the openings, the fluorescent film 1a is blown in a state where color screening is performed to realize an image.

On the other hand, the electron beam 10 emitted from the electron gun (3) must hit the R, G, B phosphor of the fluorescent film 1a accurately for each of R, G, B, the vibration from the impact and sound waves from the outside shadow When transmitted to the mask 5, the wave pattern is generated on the screen because the electron beam 10 does not strike the phosphor due to the mask vibration. This is called howling phenomenon, and in order to reduce this phenomenon, vibration occurrence in the shadow mask 5 should be finally reduced. In this way, the rigidity of the frame 6 should be increased.

In addition, a drop impact test is performed on the cathode ray tube itself, and as in the vibration howling experiment, when the final shadow mask is deformed, the screen is stained and becomes a defect, so it is tested as one of the product reliability evaluation methods. This should also increase the stiffness of the frame in an indirect way that reduces deformation of the shadow mask.

To this end, as shown in FIG. 2, a plurality of beads 6a are formed in an inclined shape on each side of the frame, and a more effective conventional method includes a single layer of beads 6b at the outer corners as shown in FIG. To form.

According to the conventional technology described above, it can be seen that a single-layer bead is formed in each side and corner portion to increase rigidity of the frame.

However, in the frame structure according to the related art, it can be seen from the stress distribution mode of FIG. 4 that most stresses (areas indicated by stains) are concentrated in corners when looking at stress distributions for various vibration mode shapes. For reference, each mode represents the vibration deformation according to the frequency change.

As a result, it can be seen that the prior art in which a large number of beads are formed on each side does not have much effect on the increase in rigidity.

Therefore, the corner bead as shown in Figure 3 can be seen that the effect of increasing the stiffness relatively large, the present invention by forming a bead shape that can further improve the stiffness with reference to the above content by forming the four corners of the frame The purpose is to improve the shock and vibration characteristics of cathode ray tubes.

1 is a partial cutaway view of a typical colored cathode ray tube.

2 is an exploded perspective view of a panel structure to which a conventional frame is applied.

3 is an enlarged view of a portion A of FIG. 2;

4 is a state diagram of stress distribution in various vibration mode shapes.

5 is an enlarged view of a frame corner portion in which beads are formed according to an embodiment of the present invention.

6A and 6B are part-specific parameters in a frame according to the embodiment.

Figure 7 is a bead form according to another embodiment of the present invention.

8 is a bead form according to another embodiment of the present invention.

*** Explanation of symbols for the main parts of the drawing ***

1: panel, 2: funnel, 3: electron gun, 4: spring, 5: shadow mask

6: frame, 6a.6b: bead (conventional), 6c.6c'.6c ": bead (invention)

The present invention for realizing the above object, a collar having a rectangular frame structure formed in the indented groove having a bead shape in the direction of the long and short axis at the outer corner portion where the long side axis and the short side axis meet has a radius In the cathode ray tube frame, the inlet groove formed in the corner portion provides a frame for color cathode ray tube, characterized in that the stepped double bead is further provided at least two or more steps.

Preferably, the indentation groove formed in the corner portion is preferably formed in a multi-stage step shape along the longitudinal direction of the groove that is around the frame.

Further preferably, the indentation groove formed in the corner portion is preferably formed in a multi-stage step shape along the width direction of the groove which is the frame thickness.

Also preferably, the total length of the beads on the long axis is α1, the two-stage bead length on the long axis is α ₂ , the total depth of the beads on the short axis is δ ₁ , and the length of the beads on the short axis is 2. When the step bead depth is referred to as δ2 and R is defined as the radius, α ₂ preferably satisfies the expression 0.1 α1 ≦ α2 ≦ [α1- (δ1 + δ2) -R].

When the two-stage bead length α2 is 0.1 or less, it becomes close to a single bead shape having a large width as in the prior art, and the effect thereof is weak, and it is difficult to realize the object according to the present invention by the limit of the radius R.

More preferably, the ratio of α2 to α1 satisfies the formula of 0.1 <(α2 / α1) 0.8.

When the ratio of α2 to α1 is 0.1 or less, the effect is weakened as the shape of a single bead having a large width as in the prior art becomes weak. It becomes impossible to realize.

Preferably, when the total length of the beads on the short axis is β1 and the two-stage bead length on the short axis is β ₂ , the ratio of β ₂ to β 1 is 0.1 <(β 2 / β 1) < It is preferable to satisfy the expression 0.8.

If the ratio of β2 to β1 is 0.1 or less, the effect becomes weaker as a single bead having a large width as in the prior art, and if 0.8 or more, the object according to the present invention cannot be realized due to the limitation of the radius R, which is the molding condition of the corner portion. Become.

Also preferably, when the total depth of the beads on the long axis is referred to as γ 1 and the two-stage bead depth on the long axis is defined as γ 2, the ratio of γ 2 to γ 1 is 0.2 <(γ 2 / γ 1) <0.8. It is desirable to satisfy.

If the ratio of γ2 to γ1 is 0.2 or less, molding becomes impossible, and if it is 0.8 or more, it becomes close to a single bead and the effect of strengthening the rigidity of the frame is weakened.

Also preferably, when the total height of the beads on the short axis is h1 and the height of the two-stage beads on the short axis is h2, the ratio of h2 to h1 is 0.2 <(h2 / h1) <0.65 It is preferable to satisfy the formula.

When the ratio of h2 to h1 is less than or equal to 0.2, molding is impossible. If it is more than 0.65, molding is difficult and close to a single bead, so that the effect of strengthening the rigidity of the frame is weakened.

In other words, when the vibration mode shape of the cathode ray tube frame is examined, it is confirmed that the stress distribution is mostly concentrated in the corner portion. Thus, as described above, the bead groove is formed as a stepped groove in the corner portion, which is a portion that determines the rigidity of the frame. It can be seen that by forming the stiffness of the structure can be further increased.

As a result, the shock and vibration characteristics of the cathode ray tube structure are improved.

And, there may be a plurality of embodiments of the present invention, hereinafter will be described in detail with respect to the most preferred embodiment.

Hereinafter, with reference to the accompanying drawings, preferred embodiments of the present invention for achieving the above object will be described in detail a preferred embodiment of the frame reinforcement structure according to the present invention.

In addition, in drawing used for description, about the component similar to the prior art, the same code | symbol is attached | subjected, and the overlapping description may be abbreviate | omitted.

5 is a bead structure of the frame corner portion according to an embodiment of the present invention, Figures 6a and 6b is a view showing the parameters of the bead structure, Figure 7 is a bead structure according to another embodiment, Figure 8 is another Figure showing a bead structure according to the embodiment.

In the frame 6 according to the present embodiment, as shown in FIG. 5, beads 6c are formed in a double stepped shape around each corner portion, that is, in a direction perpendicular to the tube axis, and according to the size of the cathode ray tube. When the numerical value of each part of the bead 6c is limited, it is as follows. (Refer FIG. 6A, FIG. 6B)

That is, the total length of the beads on the long side (α ₁ ): 0 <α ₁ <L ₁

Two-stage bead length on the long axis (α ₂ ): 0 <α ₂ <α ₁ -δ ₁

Bead length at short axis (β ₁ ): 0 <β ₁ <S ₁

Two-stage bead length on short axis (β ₂ ): 0 <β ₂ <β ₁ -γ ₁

Bead depth at long axis (γ ₁ ): 0 <γ ₁ <λ ₁

Two-stage bead depth at long axis (γ ₂ ): 0 <γ ₂ <γ ₁

Bead depth at short axis (δ ₁ ): 0 <δ ₁ <ρ ₁

Two-stage bead depth at short axis (δ ₂ ): 0 <δ ₂ <δ ₁

Total Bead Width (D): 0 <D <W

Angle of inclination of the first stage bead on the long axis (θ ₁ ): 0 <θ ₁ <180 °

Angle of inclination of the two-stage bead on the long axis (θ ₂ ): 0 <θ ₂ <180 °

Tilt angle of one-stage bead on the short axis (φ ₁ ): 0 <φ ₁ <180 °

Angle of inclination of the two-stage bead on the short axis (φ ₂ ): 0 <φ ₂ <180 °

Bead height at short axis (h1): 0 <h1 <h2

Two-stage bead depth at short axis (h2): 0 <h2 <h1

(Where L1 is 1/2 of the full length of the long side, S1 is 1/2 of the full length of the short side, W is the minimum of the total height, λ ₁ is the minimum of the long side shaft width near the corner, and ρ ₁ is near the corner) Shows the minimum value of the short axis width)

The two-layer stepped beads 6c formed within such a limited value can further increase the rigidity at the corners of the frame 6 as compared with the single-layer immersion groove shape.

In another embodiment of the present invention, as shown in FIG. 7, a double stepped bead 6c ′ is formed in the width direction, that is, the tube axis direction, or in another embodiment, as shown in FIG. 8. Forming a double stepped bead (6c ") in both directions of the combined form of the two embodiments it is possible to prevent the stress concentration in both directions can maximize the rigidity reinforcement effect of the frame.

On the other hand, as a comparative example, that is, in the prior art, a structure in which a bead is added to the corner portion of the frame to increase the rigidity was applied. It can be seen that the effect is weak compared to.

Natural frequency 1st 2nd 3rd 4th 5th Beadless Frame 69.8 244.3 289.7 370.2 391.8 Single Layer Corner Bead Frames 71.9 256.8 295.6 408.0 430.6 Multi-layered Stepped Corner Bead Frames 73.5 268.2 300.6 418.9 441.7

As a result, according to the present invention, the frame reinforcement structure is further increased as compared with the conventional one, so that the shock and vibration characteristics can be improved.

In addition, although specific embodiments of the present invention have been described and illustrated above, it is obvious that the bead shape of the present invention may be variously modified and implemented by those skilled in the art.

Such modified embodiments should not be individually understood from the technical spirit or the prospect of the present invention, and such modified embodiments should fall within the appended claims of the present invention.

As described above, the present invention has an advantage of further improving the frame rigidity by improving the bead shape where the stress distribution is concentrated, thereby improving the drop impact and vibration characteristics of the cathode ray tube.

Claims (8)

In a frame for a color cathode ray tube having a rectangular frame structure having a bead-shaped indentation groove having a radius shared at an outer corner where the long side axis and the short side axis meet each other: The indentation groove formed in the corner portion is a frame for color cathode ray tube, characterized in that further provided with at least two or more stepped double beads. The method of claim 1, The indentation groove formed in the corner portion, the frame for color cathode ray tube, characterized in that formed in a multi-stepped step along the longitudinal direction of the groove around the frame. The method according to claim 1 or 2, The indentation groove formed in the corner portion is a frame for color cathode ray tube, characterized in that formed in a plurality of steps in the width direction of the groove which is the frame thickness. The method of claim 1, The total length of the beads on the long side axis is α1, the two-stage bead length on the long side axis is α ₂ , the total depth of the beads on the short side axis is δ 1, and the two-stage bead depth on the short side axis is δ ₂ . When R is a radius, α ₂ satisfies the formula 0.1 α1 ≦ α2 ≦ [α1- (δ1 + δ2) -R]. The method of claim 4, wherein The ratio of α2 to α1 satisfies the formula 0.1 <(α2 / α1) 0.8. The method of claim 1, When the total length of the beads on the short side axis is β1 and the two-stage bead length on the short side axis is β ₂ , the ratio of β ₂ to β 1 satisfies the expression 0.1 <(β 2 / β 1) <0.8. The frame for color cathode ray tubes characterized by the above-mentioned. The method of claim 1, When the total depth of the beads on the long axis is referred to as γ 1 and the two-stage bead depth on the long axis is referred to as γ 2, the ratio of γ 2 to γ 1 satisfies the expression 0.2 <(γ 2 / γ 1) <0.8. Frame for color cathode ray tubes. The method of claim 1, When the height of the bead on the short axis is h1 and the height of the two-stage bead on the short axis is h2, the ratio of h2 to h1 satisfies the expression 0.2 <(h2 / h1) <0.65. The frame for color cathode ray tubes characterized by the above-mentioned.