JPH11120939A - Funnel for cathode-ray tube - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a funnel for a cathode-ray tube capable of satisfactorily passing an electron beam deflected into a wide angle without deteriorating the mechanical strength of a yoke fitting section and having good productivity. SOLUTION: This funnel-shaped funnel is provided with a wide opening end section connected with a nearly rectangular panel and a narrow opening end section connected with a neck tube. The outer contour of a yoke fitting section 1c fitted with a deflection yoke is formed into a nearly rectangular shape, and its inner contour is formed into a curved shape expanded inward at the center sections of opposite sides. The thickness TD on the diagonal axis between the outer contour and the inner contour, the thickness TH on the horizontal axis, and the thickness TV on the vertical axis have the relations TD<TH and TD<TV.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a funnel for a cathode ray tube.

[0002]

2. Description of the Related Art A cathode ray tube funnel has a wide opening end for joining a substantially rectangular panel on which an image is projected and a narrow opening end for joining a neck tube into which an electron gun is inserted. The panel and the neck tube are joined to the funnel to provide a cathode ray tube bulb.

When a cathode ray tube is operated, an image is displayed by irradiating an electron beam emitted from an electron gun in a neck tube to an inner surface of a panel. Therefore, an electron beam is provided outside a narrow opening end side of a funnel for a cathode ray tube. A deflection yoke for deflecting the beam is mounted.

However, when deflecting the electron beam, the electron beam which strikes particularly the corner of the substantially rectangular panel does not reach the panel because the inner wall of the yoke mounting portion of the funnel for the cathode ray tube is hindered, and is called a so-called neck shadow. This causes a problem that a desired image cannot be obtained.

Therefore, conventionally, for example, there has been proposed a funnel for a cathode ray tube in which a concave groove through which an electron beam hitting a corner of a panel passes is formed on an inner wall of a yoke mounting portion.

[0006]

However, in the above-mentioned cathode ray tube funnel, there is a problem that the mechanical strength is remarkably deteriorated because only the concave groove portion is locally thinned. That is, when the cathode ray tube bulb is used as a cathode ray tube, the inside thereof is evacuated and used as a vacuum vessel, so that it is always in a state of being stressed by the atmospheric pressure, so that it can withstand this. Sufficient mechanical strength is required. In particular, the yoke mounting portion of the funnel is one of the regions where the cause of destruction of the cathode ray tube is likely to occur, and forming a local thin portion in such a portion causes a problem in strength. In addition, such a funnel having a local thin portion is not only difficult to mold,
For example, even when a doug (conductive film) is formed on the inner wall of the funnel in the tube process, there is a problem that the dough is accumulated in the concave groove portion and it is difficult to apply the conductive film.

It is an object of the present invention to provide a cathode ray tube funnel which can pass an electron beam which is deflected at a wide angle in a favorable state without deteriorating the mechanical strength of the yoke mounting portion and which has high productivity. It is to be.

[0008]

SUMMARY OF THE INVENTION The present invention has been made in view of the above problems and objects, and has a wide opening end to which a substantially rectangular panel is joined and a narrow opening end to which a neck tube is joined. In the funnel-shaped funnel having, the outer contour of the yoke mounting portion to which the deflection yoke is mounted is substantially rectangular,
The inner contour has a curved shape in which the center of the opposing sides bulges inward, and the thickness TD on the diagonal axis DA between the outer contour and the inner contour, the thickness TH on the horizontal axis HA, A funnel for a cathode ray tube, wherein a thickness TV on a vertical axis VA has a relationship of TD <TH and TD <TV.

Also, the horizontal axis HA of the yoke mounting portion is set to 0.
゜, the vertical axis VA is 90 °, the angle between the diagonal axis DA and the horizontal axis HA is Dθ, and the thickness T at the angle θ is 0 <
TH + (TD−TH) where θ <Dθ (θ / Dθ)
^X , TV + (TD−TV) when Dθ <θ <90
[(90−θ) / (90−Dθ)] ^X (where 1 <X ≦
8).

[0010]

In the funnel for a cathode ray tube according to the present invention, the outer contour of the yoke mounting portion to which the deflection yoke is mounted is substantially rectangular, and the inner contour thereof is a curved shape in which the center of the opposing sides bulges inward. The thickness TD on the diagonal axis DA, the thickness TH on the horizontal axis HA, and the thickness TV on the vertical axis VA between the outer contour and the inner contour have a relationship of TD <TH and TD <TV. By doing so, the inner contour of the yoke mounting part is
It has a shape substantially similar to the passing shape of the electron beam group at the yoke mounting portion, and furthermore, the thickness of the corner portion of the yoke mounting portion through which the electron beam deflected at the widest angle passes is reduced to prevent the passage of the electron beam. The mechanical strength required in the yoke mounting portion is maintained without increasing the thickness from the corner portion toward the horizontal axis and the vertical axis.

In the present invention, the horizontal axis HA of the yoke mounting portion is 0 °, the vertical axis VA is 90 °, and the diagonal axis D is
Assuming that the angle between A and the horizontal axis HA is Dθ, the thickness T at the angle θ is TH + (TD−T−0) at 0 <θ <Dθ.
H) (θ / Dθ) ^X , TV + at Dθ <θ <90
(TD-TV) [(90-θ) / (90-Dθ)] ^X ,
(Where 1 <X ≦ 8), particularly the thin portion on the diagonal axis of the yoke mounting portion has an inner contour that does not exhibit an extremely narrow concave groove shape, and the thin portion on the diagonal axis. And the thick portions on the horizontal axis and the vertical axis have a smooth curved shape.

[0012]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, a funnel for a cathode ray tube according to the present invention will be described based on embodiments.

FIG. 1 is an explanatory view of a funnel 1 for a cathode ray tube according to the present invention, and FIG. 2 is an enlarged sectional view taken along line AA of FIG.

The funnel 1 for a cathode ray tube has a wide opening end 1a for joining a substantially rectangular panel and a narrow opening end 1b for joining a neck tube. As shown in FIG. 2, the yoke mounting portion 1c to which the deflection yoke is mounted has an outer contour that is substantially rectangular, and an inner contour that is a curved shape in which the center of opposing sides swells inward. Thickness T on the diagonal axis DA between the outer contour and the inner contour of the part 1
D, thickness TH on the horizontal axis HA, thickness TV on the vertical axis VA
Are respectively TD = 2.7 mm, TH = 3.6 mm, TV =
It is formed to 4.0 mm.

The curved shape of the inner contour is obtained by satisfying the following conditions.

FIG. 3 is a sectional view of the yoke mounting portion 1c.
/ 4 region is shown in an enlarged manner, and here, the yoke mounting portion 1 is shown.
c, horizontal axis HA is 0 °, vertical axis VA is 90 °, diagonal axis D
Assuming that the angle between A and the horizontal axis HA is Dθ, and the perpendicular distance from the intersection B between the axis and the outer contour of the yoke mounting portion 1c to the inner contour at the angle θ is thickness T, the thickness T is 0 < θ <
In Dθ, TH + (TD−TH) (θ / Dθ) ^X , D
When θ <θ <90, TV + (TD−TV) [(90−
θ) / (90−Dθ)] ^X , where 1 <X ≦ 8, so that the thickness T on the diagonal axis DA described above.
D, while maintaining the values of the thickness TH on the horizontal axis HA and the thickness TV on the vertical axis VA, the inner contour exhibits a smooth curved shape. Here, the larger the multiplier in the above conditional expression, the larger the constriction amount near the diagonal axis DA of the curved inner contour, that is, the greater the thinning near the diagonal axis DA, but the case where the multiplier is 1 If the inner contour does not exhibit a curved shape, and if the multiplier is larger than 8, the thin portion near the diagonal axis DA will exhibit an extremely narrow groove shape.

In the present embodiment, Dθ is 36.87 °, and the thickness T at each angle θ is such that the angle θ is 0 <θ <3.
In the case of 6.87, TH + (TD−TH) (θ / 36.8
7) ^2, 36.87 <θ <time of 90 TV + (TD-T
V) [(90−θ) / (90−36.87)] ² .

The funnel for a cathode ray tube in which the thickness T of the yoke mounting portion 1c is changed based on such conditions, the thickness TD on the diagonal axis DA of the yoke mounting portion 1c and the horizontal axis H
The thickness TH on A and the thickness TV on the vertical axis VA are TD <T
Although H and TD <TA, the inner contour has a smooth curved shape, so that the passage of the electron beam is not hindered and the mechanical strength required for the yoke mounting portion 1c is maintained. be able to.

[0019]

As described above, according to the funnel for a cathode ray tube of the present invention, it is possible to pass an electron beam which is deflected at a wide angle satisfactorily without deteriorating the mechanical strength of a yoke mounting portion. In addition, it has an excellent effect that it can contribute to productivity.

[Brief description of the drawings]

FIG. 1 is an explanatory view of a funnel for a cathode ray tube according to the present invention.

FIG. 2 is an enlarged sectional view taken along line AA of FIG.

FIG. 3 is an explanatory diagram of a thickness distribution in a yoke mounting portion.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Funnel for cathode ray tube 1a Wide opening end 1b Narrow opening end 1c Yoke mounting part

Claims (2)

[Claims] 1. In a funnel-shaped funnel having a wide opening end to which a substantially rectangular panel is joined and a narrow opening end to which a neck tube is joined, an outer contour of a yoke attaching portion to which a deflection yoke is attached is substantially. It has a rectangular shape, and its inner contour has a curved shape in which the center of the opposing sides bulges inward, and has a thickness TD on the diagonal axis DA between the outer contour and the inner contour, and on the horizontal axis HA. Thickness TH, thickness TV on vertical axis VA is TD
A funnel for a cathode ray tube, wherein a relationship of <TH and TD <TV is satisfied. 2. The horizontal axis HA of the yoke mounting portion is 0 °,
Assuming that the vertical axis VA is 90 ° and the angle between the diagonal axis DA and the horizontal axis HA is Dθ, the thickness T at the angle θ is 0 <θ <
In Dθ, TH + (TD−TH) (θ / Dθ) ^X , D
When θ <θ <90, TV + (TD−TV) [(90−
θ) / (90−Dθ)] ^X , where 1 <X ≦ 8, the funnel for a cathode ray tube according to claim 1, wherein