JP3637590B2 - Funnel for cathode ray tube - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to weight reduction of a funnel for a cathode ray tube for television reception.
[0002]
[Prior art]
Generally, a cathode ray tube for receiving television has a front panel portion, a rear funnel-shaped funnel portion, and a neck portion containing an electron gun. As shown in FIGS. 3A and 3B, the funnel portion includes a yoke portion a on the small opening end side and a body portion b on the large opening end side, and is orthogonal to the central axis X of the body portion b. The cross section to be formed has a substantially rectangular shape, and has a major axis L, a minor axis S, and a diagonal axis D.
[0003]
The conventional funnel F for a cathode ray tube has thicknesses at arbitrary heights h on the long axis L, the short axis S, and the diagonal axis D, which are T (Lh), T (Sh), and T (Dh), respectively. In the first quadrant of 0 ° ≦ θ ≦ 90 °,
T (θh) = T (Lh) + (T (Dh) −T (Lh)) sin ² ((90 ° × θ) / d °) in the range of L (0 °) ≦ θ ≦ D (d °) ,
T (θh) = T (Sh) + (T (Dh) −T (Sh)) sin ² ((90 ° × (90 ° −θ)) in the range of D (d °) ≦ θ ≦ S (90 °) ) / (90 ° -d °))
The thickness between each axis was determined at T (θh) (see FIG. 4).
[0004]
In the second quadrant (90 ° ≦ θ ≦ 180 °), the third quadrant (180 ° ≦ θ ≦ 270 °), and the fourth quadrant (270 ° ≦ θ ≦ 360 °), the above two equations are used. Accordingly, a wall thickness distribution was formed symmetrically.
[0005]
[Problems to be solved by the invention]
However, cathode ray tubes for television reception increase in weight as they become larger, and are inconvenient to transport and handle, so that weight reduction is required. In order to achieve this weight reduction, it is only necessary to reduce the wall thickness. However, if the wall thickness is simply reduced, the mechanical strength is lowered and the conditions stipulated in the required safety standards are not satisfied.
[0006]
Accordingly, an object of the present invention is to provide a funnel for a cathode ray tube that can reduce the weight without impairing the mechanical strength.
[0007]
[Means for Solving the Problems]
In order to achieve the above object, the present invention comprises a yoke portion on the small opening end side and a body portion on the large opening end side, and each transverse section (Ph) orthogonal to the central axis X of the body portion has In a funnel for a cathode ray tube having a substantially rectangular shape and having a major axis L, a minor axis S, and a diagonal axis D,
Each arbitrary cross section (Ph) is divided into four quadrants every 90 ° with the central axis X as the center, and an angle θ around the central axis X with respect to the major axis L (provided that each quadrant is divided) , 0 ° ≦ θ ≦ 90 °), the thickness on the long axis L (in this case, θ = 0 °) is T (Lh), and the short axis S (in this case, θ = 90 °) The thickness at the top is T (Sh), the thickness at the diagonal axis D (θ = d ° at this time) is T (Dh), and the thickness at an arbitrary angle (θ) is T (θh). ) In at least one quadrant,
T (Dh)> T (Lh), T (Dh)> T (Sh), and
0 ° ≦ θ ≦ (d−α) ° {where T (θh) = T (Lh) in the region of 0 ° <α <d °},
In the region of (d + β) ° ≦ θ ≦ 90 ° {where 0 ° <β <(90−d) °}, T (θh) = T (Sh).
[0008]
Since the present invention has the above-described configuration, the mechanical strength is not impaired by setting the wall thickness on each of the major axis L, the minor axis S, and the diagonal axis D in the same manner as in the past. A uniform thickness region that is the same as the thickness on the major and minor axes of the thin wall than the thickness on the diagonal axis is in the range (d−α) ° from the major axis L and 90 ° − (d + β) °. To the minor axis S, the weight can be reduced and the weight can be reduced. As the values of α and β are decreased, the uniform thickness region can be increased, and the weight can be reduced and the weight can be reduced.
[0009]
The present invention is characterized in that α is 10 ° ≦ α <d and β is 10 ° ≦ β <(90−d) °. When α is 10 ° or less, it is difficult to smoothly form the thickness change in the gradually increasing region from the thickness T (Lh) to the thickness T (Dh) on the diagonal axis. Further, when β is 10 ° or less, it is difficult to smoothly form a change in thickness in the gradually decreasing region from the thickness T (Dh) on the diagonal axis to the thickness T (Sh). Note that as α approaches d ° and β approaches (90−d) °, the weight reduction decreases, so α is in a range smaller than d °, and β is (90−d). The angle should be as small as possible within a range smaller than °.
[0010]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, embodiments of the present invention will be described with reference to the drawings. FIG. 1A is a cross-sectional plan view of the funnel for a cathode ray tube at an arbitrary height h from the reference line for explaining the present invention at 90 ° (first quadrant), and FIG. 1B is a side view of the entire funnel. FIG. 2 and FIG. 2 are graphs showing an example of the thickness distribution state of 90 ° (first quadrant) of the funnel according to the present invention.
[0011]
As shown in FIGS. 1A and 1B, the present invention includes a yoke portion a on the small opening end side and a body portion b on the large opening end side, and is orthogonal to the central axis X of the body portion b. In a cathode ray tube funnel F having a substantially rectangular cross section and having a major axis L, a minor axis S, and a diagonal axis D, the neck portion e, the yoke portion a, the seal edge portion j, the anode button portion k, and the alignment portion g are excluded. The thickness of the body portion b at an arbitrary height h from the reference line m is formed as follows.
[0012]
That is, T (Lh) on the long axis L (in this case, θ = 0 °), T (Sh) on the short axis S (in this case, θ = 90 °), and the diagonal axis D (in this case, θ = d ()), and T (Dh) is the thickness of T (Dh), and T (Dh) is thicker than T (Lh) and T (Sh). When β is 0 ° <α <d ° and 0 ° <β <(90−d) °, as shown in FIG.
Forming a uniform thickness region of T (θh) = T (Lh) in a range of 0 ° ≦ θ ≦ (d−α) °; and
A uniform thickness region of T (θh) = T (Sh) is formed in a range of (d + β) ° ≦ θ ≦ 90 °,
A gradually increasing region from T (Lh) to T (Dh) is formed in the range from θ = (d−α) ° to the diagonal axis D, and θ = (d + β) ° from the diagonal axis D. In this range, a thickness gradually decreasing region from T (Dh) to T (Sh) is formed, and the distribution of the thickness is distributed to other parts constituting the funnel F, that is, 90 ° ≦ θ ≦ 180 ° ( Second quadrant), 180 ° ≦ θ ≦ 270 ° (third quadrant), and 270 ° ≦ θ ≦ 360 ° (fourth quadrant).
[0013]
In this case, the thickness distribution formed in the first quadrant region of 0 ° ≦ θ ≦ 90 ° is symmetrical with respect to the major axis L and the minor axis S in the other second to fourth quadrant regions. It is more preferable to form a thickness distribution at each height h of the funnel body part b. As a result, the maximum weight reduction can be achieved, and the weight distribution of the funnel F becomes point-symmetric at an arbitrary height h on the central axis, thereby forming a desired thickness distribution at the time of funnel glass molding. The reproducibility of accuracy can be increased, and as a result, the funnel strength can be maintained more easily.
[0014]
The reason why the neck portion e, the yoke portion a, the seal edge portion j, the anode button portion k, and the alignment portion g are excluded from the thickness distribution of the present invention is as follows. That is, the neck portion e is a portion that houses the electron gun, and has a uniform thickness. The yoke portion a is a portion that extends to the body portion b following the neck portion e in order to mount a deflection yoke coil for deflecting the electron beam irradiated from the electron gun on the outer wall. The distribution is gradually increased and changed in the direction of the central axis X of the body part b. At this time, the cross-sectional thickness in the direction perpendicular to the central axis X is usually the same around the axis X. ing. Moreover, the seal edge part j is a part sealed with a panel part (illustration omitted), and is made into uniform thickness. Furthermore, the anode button part k is formed to be slightly thinner than other parts for implantation of the anode button. The alignment portion g is formed in the vicinity of the seal edge portion j of the funnel F, and is used as an alignment reference point when the glass bulb is formed by sealing with a cathode ray tube panel and a sealing material. A plurality of positioning reference surfaces are formed with a predetermined distance from the central axis X of the funnel F, and are perpendicular to the seal edge surface. Therefore, as a result, the thickness of the alignment part g becomes thick according to the outward protrusion of the funnel F.
[0015]
Next, in order to confirm the effect of the present invention,
1. Diagonal outer diameter 34 "(aspect ratio (aspect ratio) 4: 3), deflection angle 110 °, flat bulb (planar cathode ray tube)
2. Diagonal outer diameter 38 "(aspect ratio (aspect ratio) 4: 3), deflection angle 104 °, flat bulb (planar cathode ray tube)
An example and a comparative example were manufactured in accordance with the specifications described above, and the results of a weight comparison and a strength test by a ball impact method and a missile method according to UL1418 (US safety standard) were compared. However, the missile method uses a diamond cutter to place a 10 cm long scratch on the long side of the panel face near the effective screen display end, and then apply a maximum of 20 joules of energy to the missile steel object. Impact the face part. In this test method, the cathode ray tube is destroyed by the impact, and the acceptance / rejection determination is made based on the size of the glass pieces scattered at that time. The ball impact method is a test method in which a steel ball having a diameter of 50 mm is dropped in a pendulum shape on the effective screen of the panel face portion with an energy of 7 joules, and pass / fail judgment is performed based on the size of the glass pieces scattered at that time.
[0016]
The above embodiment is manufactured with the wall thickness distribution according to the present invention, and the comparative example is manufactured with the conventional wall thickness distribution, and the wall thicknesses T (Sh), T (Lh) at a certain height h on each axis, T (Dh) was equal between the two. The funnel thickness distribution in each quadrant from the first to the fourth is a line in either the major axis or the minor axis passing through the center of the substantially quadrangular shape of the cross section of the body portion at an arbitrary height h in the examples and comparative examples. Formed as symmetric. In the embodiment of the present invention, α = the diagonal outer diameter 34 ″ (aspect ratio 4: 3) and 2 = the diagonal outer diameter 38 ″ (aspect ratio 4: 3). 17 ° and β = 23 °.
[0017]
On the other hand, the cathode ray tube panels (not shown) used for forming the bulbs sealed with the funnel F were the same panels in the examples and comparative examples for 34 ″ and 38 ″, respectively.
[0018]
The white circles in FIG. 2 are the thickness distribution of the example according to the present invention, and the black circles are the thickness distribution of the conventional comparative example. For example, when the distance in the central axis X direction between the reference line m and the seal edge j is H, the thickness (mm) at the heights h = 1 / 2H and h = 3 / 4H is the diagonal outer diameter. 34 ″ and 38 ″ are as described in Table 1, respectively.
[0019]
Table 2 shows the comparison results. As is clear from Table 2, the weight comparison between Example 1 and Comparative Example 1 was 3% lighter, and Example 2 and Comparative Example 2 was 4% lighter. In addition, in the intensity comparison, there was no occurrence of nonstandard values in each of the examples and comparative examples. From this, it has been confirmed that the present invention can reduce the weight of the funnel without losing the strength. In FIG. 2, the difference between the black circle and the white circle corresponds to the amount by which the thickness can be reduced by the present invention. Moreover, although the said Example and the comparative example showed the case of aspect ratio 4: 3, it is applicable also in the case of other ratios. The specific angle d of the diagonal axis D when the aspect ratio is 4: 3 is 36.87 °, and the angle d of the diagonal axis D when the aspect ratio is 16: 9 is 29.35 °. The
[0020]
[Table 1]
[0021]
[Table 2]
[0022]
【The invention's effect】
According to the present invention, the weight can be reduced by reducing the weight without impairing the mechanical strength of the funnel for a cathode ray tube.
[Brief description of the drawings]
FIG. 1A is a cross-sectional plan view of a funnel for a cathode ray tube at a position of an arbitrary height h from a reference line for explaining the thickness distribution of the present invention for 90 ° (first quadrant), and FIG. A side view of the entire funnel.
FIG. 2 is a graph showing an example of a thickness distribution state of 90 ° (first quadrant) of the funnel according to the present invention.
FIG. 3A is a cross-sectional plan view of a funnel for a cathode ray tube at a position of an arbitrary height h from a reference line for explaining a conventional wall thickness distribution for 90 ° (first quadrant), and FIG. 3B is a funnel. Overall side view.
FIG. 4 is a graph showing a thickness distribution state of 90 ° (first quadrant) of a conventional funnel.
[Explanation of symbols]
a Yoke part b Body part X Center axis D Diagonal axis e Neck part g Alignment part F Funnel h Height from reference line j Seal edge part k Anode button part L Long axis m Reference line S Short axis

Claims (4)

A yoke part on the small opening end side and a body part on the large opening end side are provided, and each transverse section (Ph) orthogonal to the central axis X of the body part is substantially square, and the major axis L and minor axis S In a funnel for a cathode ray tube having a diagonal axis D,
Each arbitrary cross section (Ph) is divided into four quadrants every 90 ° with the central axis X as the center, and an angle θ around the central axis X with respect to the major axis L (provided that each quadrant is divided) , 0 ° ≦ θ ≦ 90 °), the thickness on the long axis L (in this case, θ = 0 °) is T (Lh), and the short axis S (in this case, θ = 90 °) The thickness at the top is T (Sh), the thickness at the diagonal axis D (θ = d ° at this time) is T (Dh), and the thickness at an arbitrary angle (θ) is T (θh). ) In at least one quadrant,
T (Dh)> T (Lh), T (Dh)> T (Sh), and
0 ° ≦ θ ≦ (d−α) ° {where T (θh) = T (Lh) in the region of 0 ° <α <d °},
A funnel for a cathode ray tube, wherein T (θh) = T (Sh) in the region of (d + β) ° ≦ θ ≦ 90 ° {however, 0 ° <β <(90−d) °}.   In the four quadrants, the funnel for a cathode ray tube satisfying the relationship according to claim 1.   In the region of (d−α) ° ≦ θ ≦ d °, the thickness gradually increases from T (Lh) to T (Dh), and in the region of d ° ≦ θ ≦ (d + β) °, the thickness starts from T (Dh). 3. The funnel for a cathode ray tube according to claim 1, wherein the funnel gradually decreases to T (Sh).   4. The funnel for a cathode ray tube according to claim 1, wherein α is 10 ° ≦ α <d °, and β is 10 ° ≦ β <(90−d) °. 5.