JPH07312185A - Field correcting band-shaped sheet for deflecting yoke - Google Patents

Abstract

PURPOSE:To provide a field correcting band-shaped sheet for a deflecting yoke capable of locally correcting only a field in a correction objective location without putting out of order the field except a correction object. CONSTITUTION:In a field correcting band-shaped sheet 1 for a deflecting yoke, a ferrite powder compounded resin-made small piece 3 is mounted on one end in the lengthwise direction of an elastically deformable synthetic resin-made band-shaped sheet 2, also to provide a fixing means 4 in the other end. A heat resisting synthetic resin, used in a ferrite powder compounded resin, is set to 55 to 90 rubber hardness and 50 to 200% elongation percentage, and further a compounding amount of ferrite powder in the ferrite powder compounded resin is 80 to 90wt.%, also to set width of the ferrite powder compounded resin- made small piece to 2.5 to 6.0mm, further to set its permeability mu to 10 to 20.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a magnetic field correcting strip-like sheet used for final adjustment of a magnetic field of a deflection yoke mounted on a neck portion of a cathode ray tube.

[0002]

2. Description of the Related Art A deflection yoke mounted on a cathode ray tube used in a television, a CRT display or the like has a small piece f made of a ferrite powder mixed resin attached to the inner surface of the deflection yoke A as shown in FIG. 4 for the purpose of correcting a magnetic field. Has been. And
After roughly adjusting the magnetic field with a small piece f of resin containing ferrite powder, the deflection yoke A is attached to the neck portion of the cathode ray tube. However, although the above-mentioned magnetic field correction is generally correct, it is not completely precisely adjusted to the extent that it can be shipped. Therefore, the final adjustment of the magnetic field of the deflection yoke is performed again immediately before shipping.

For this final adjustment, a magnetic field correcting band-shaped sheet having a form as shown in FIG. 5 is used. As for the magnetic field correction belt-shaped sheet a, a small piece c made of a resin containing ferrite powder (hereinafter referred to as a ferrite sheet piece c) is attached to one end in the longitudinal direction of a synthetic resin belt-shaped sheet b which is elastically deformable, and a sticking means d is attached to the other end. Is provided. When using the magnetic field correcting strip-shaped sheet a, the magnetic field correcting strip-shaped sheet a is inserted through the gap between the cathode ray tube B and the deflection yoke A, and the setting position of the ferrite sheet piece c located on the tip side is finely moved. The image on the screen is inspected and fixed at the position where the image of the cathode ray tube is in the optimum state by using the attaching means d. The attaching means d may be adhered to the inner surface of the deflection yoke A as shown in FIG. 6 (a), or may be adhered to the cathode ray tube wall as shown in FIG. 6 (b). The inner surface of the deflection yoke A may be adhered to the surface of the winding wire, but normally, a base portion (not shown) for winding the winding wire is used.
Adhesively fixed to. Further, in the illustrated example, the ferrite sheet piece c and the attaching means d are attached to the same surface of the synthetic resin strip sheet b, but they may be attached to the opposite surfaces. A plurality of such magnetic field correcting strips a are usually used to adjust one television or CRT display.

The ferrite sheet piece c is attached to the synthetic resin belt-like sheet b by an adhesive c1 as shown in the enlarged view of the main part of FIG. Further, a so-called double-sided adhesive tape is used for the sticking means d, and its detailed configuration is, as shown in FIG. 8, on the synthetic resin strip sheet b, in order from the bottom, the adhesive layer d1 and the sponge base material d2. , Adhesive layer d
3 and the release paper d4 are laminated. In some cases, instead of the adhesive c for fixing the ferrite sheet piece c to the synthetic resin band-like sheet b, a double-sided adhesive tape having a structure similar to that of the attaching means d is used.

The ferrite sheet piece c has a width of 10 mm, a length of 20 mm, and a thickness of about 0.4 mm, and is formed from a material in which soft ferrite powder is dispersed and mixed in a synthetic resin. As the synthetic resin, polyvinyl chloride, polyamide, chlorinated polyethylene, acrylonitrile butadiene rubber, olefin rubber or the like is used, and the blending amount of soft ferrite is adjusted to about 70 to 79% by weight,
The magnetic permeability μ is set in the range of 5-9.

[0006]

Although the magnetic field correcting belt-like sheet a having the above-mentioned structure is the most suitable as a magnetic field correcting tool for the deflection yoke up to the present, a large-sized television set and a high-definition device which have recently appeared. In a CRT display for display, an insufficient point remains when trying to perform more accurate correction. That is, in the high-definition display, for example, when the above-mentioned magnetic field correction strip-shaped sheet is used to correct the distortion of characters or pictures displayed on the edge of the screen, the magnetic field is corrected at the corresponding portion, but the correction unnecessary portion near the corresponding portion is made. There is a problem in that it also affects the magnetic field of, and disturbs the magnetic field other than the correction target portion. As described above, the conventional magnetic field correcting strip-shaped sheet has a problem that it is difficult to locally correct only a magnetic field in an extremely limited range. The present invention has been made in view of such a current situation, and in the magnetic field correction belt-like sheet used when the magnetic field of the deflection yoke is finally adjusted in a state where the magnetic field is attached to the cathode ray tube, the correction is performed without disturbing the magnetic field other than the correction purpose. An object of the present invention is to provide a strip sheet for magnetic field correction capable of locally correcting only the magnetic field at a target location.

[0007]

The inventor of the present invention has the idea that the width of the ferrite sheet piece c should be narrowed in order to narrow the range of the magnetic field correction effect of the magnetic field correction strip-shaped sheet. I realized that if this idea is executed as it is, the magnetic field other than the part to be corrected is not disturbed, but the magnetic field correction effect in the target range to be corrected also weakens. To reduce the magnetic field correction effect due to the narrowing of the width of the ferrite sheet piece, we also examined how to supplement the magnetic field correction effect by increasing the thickness of the ferrite sheet piece, but the gap between the inner surface of the deflection yoke and the cathode ray tube wall is extremely small. It was concluded that there is a limit to thickening the ferrite sheet piece because it is narrow. As a result of intensive studies on means for solving the above-mentioned problems based on such a premise, it was found that a method of increasing the mixing ratio of the soft ferrite powder to increase the magnetic permeability μ can be adopted.
However, increasing the blending amount of the soft ferrite powder causes a problem that molding of the ferrite powder blending resin becomes difficult, and the flexibility of the synthetic resin as the binder is extremely important.
Moreover, when the receiver is used, the inner surface of the deflection yoke is always 10
Since the synthetic resin is exposed to a high temperature of 0 ° C or higher, heat resistance is also required for a long time, and since it drops to room temperature when the receiver is not used, it is necessary to withstand the temperature cycle between high temperature and room temperature. However, it is important to select a synthetic resin that satisfies these flexibility and long-term heat resistance. In principle, the narrower the width of the ferrite sheet piece, the more locally the magnetic field can be corrected, but if it is too narrow, the synthetic resin strip sheet set to the same width as the ferrite sheet piece may be twisted during installation. Yes, the width of the ferrite sheet piece must be set in consideration of these.

According to the present invention satisfying all these conditions, a small piece made of a resin containing ferrite powder is attached to one end in the longitudinal direction of an elastically deformable synthetic resin strip-shaped sheet by an adhesive, and the other end is formed on the inner surface of the deflection yoke or A strip-shaped sheet for magnetic field correction of a deflection yoke, which is provided with a sticking means to a cathode ray tube wall and is inserted into a gap between the deflection yoke mounted on the cathode ray tube and the cathode ray tube and fixed by the sticking means. The heat-resistant synthetic resin used as the powder-blended resin has a rubber hardness of 55 to 90 and an elongation of 50 to 2
The content of the ferrite powder in the ferrite powder-containing resin is 80 to 90% by weight, and the width of the ferrite powder-containing resin small piece is 2.5 mm to 6.0 mm.
And has a magnetic permeability μ of 10 to 20.

As the heat-resistant synthetic resin, chlorosulphonated polyethylene resin can be used.

The adhesive for adhering the synthetic resin strip-shaped sheet and the ferrite sheet piece is preferably an acrylic adhesive.

[0011]

The strip-shaped magnetic field correcting sheet having such a structure is used by inserting it into the gap between the deflection yoke and the cathode ray tube as in the conventional strip-shaped magnetic field correcting sheet. In the magnetic field-correcting strip-shaped sheet of the present invention, the heat-resistant synthetic resin used as the ferrite powder-containing resin has a rubber hardness of 55 to 90 and an elongation of 50.
~ 200%, so 80% to 90% by weight of ferrite powder
The composition can be molded even if mixed to a certain extent, and the flexibility after molding is maintained, and the high permeability of ferrite powder allows the permeability μ to be in the range of 10 to 20 without increasing the thickness of the ferrite sheet piece. As a result, the width of the ferrite sheet piece can be increased from 0.5 mm to
It becomes possible to make the width as narrow as 6.0 mm. Further, since the ferrite sheet piece of this magnetic field correction strip-shaped sheet has a narrow width and has a sufficient magnetic permeability μ, local magnetic field correction of the deflection yoke can be effectively performed.

When a chlorosulfonated polyethylene resin is used as the heat-resistant synthetic resin as described in claim 2, the ferrite powder can be highly filled and the flexibility of the ferrite powder-containing resin after filling can be satisfied. In addition, it can exhibit flame retardancy and sufficient long-term heat resistance.

When an acrylic adhesive is selected as the adhesive for adhering the synthetic resin strip-shaped sheet and the ferrite sheet piece as in claim 3, the adhesive itself is excellent in heat resistance, so that the deflection It is possible to maintain a predetermined sticking posture for a long period of time without deterioration of the adhesive performance due to the temperature rise of the yoke.

[0014]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The details of the present invention will be described below with reference to illustrated embodiments. FIG. 1 is an external view of a magnetic field correcting strip-shaped sheet 1 of the present invention. The external appearance is formed narrower than that of the conventional magnetic field correcting strip-shaped sheet described in FIG. Similar to the conventional magnetic field correcting strip-shaped sheet, the magnetic field correcting strip-shaped sheet 1 has a ferrite sheet piece 3 attached to one end in the longitudinal direction of an elastically deformable synthetic resin strip-shaped sheet 2 and an attaching means 4 on the other end side. It is provided. The ferrite sheet piece 3 is set to have the same width as the synthetic resin strip sheet 2, and its width W is set to a range of 2.5 mm to 6.0 mm. 6.
If it exceeds 0 mm, there will be no difference from the conventional product, and it will not be suitable for local adjustment. The narrower is more advantageous for more precise adjustment, but if it is smaller than 2.5 mm, the synthetic resin strip 2 having the same width as the ferrite sheet piece 3 is easily twisted, and the deflection yoke and the cathode ray tube are separated. Construction in the gap becomes difficult. At present, there is no demand for precise adjustment accuracy such that the width is set to less than 2.5 mm.

The length L of the ferrite sheet piece 3 is 20 m.
m, and the thickness D is 0.4 mm. Ferrite sheet piece 3
The length L and the thickness D may be changed as necessary.
However, if the thickness D of the ferrite sheet piece 3 is too large, it becomes difficult to insert it into the gap between the deflection yoke and the cathode ray tube.

The ferrite sheet piece 3 is formed from a material in which ferrite powder is dispersed and mixed in a synthetic resin, and as the ferrite powder, soft ferrite powder such as manganese zinc ferrite, nickel zinc ferrite, magnesium ferrite or the like can be used. The blending amount of ferrite powder is set to 80 to 90% by weight, and the magnetic permeability μ is 10 to 20.
It is set to the range of. If the blending amount of the ferrite powder is less than 80% by weight, the magnetic permeability is too low and the effect of magnetic field correction is insufficient. On the other hand, it depends on the binder resin, but generally 9
If it exceeds 0% by weight, it will be difficult to mold the ferrite powder-containing resin, and even if it can be molded, it will not be flexible,
In the gap between the deflection yoke and the cathode ray tube, the bent shape of the synthetic resin strip-shaped sheet 2 used in a curved state cannot be followed.

The synthetic resin serving as a binder must be capable of being highly filled with ferrite powder, and has a rubber hardness of 55 to 9
0 and an elongation of 50 to 200% are selected. When the rubber hardness is less than 55, the shape retention is poor, and when it exceeds 90, the flexibility is poor. If the elongation is less than 50, the ferrite sheet piece 3 may tear when the ferrite sheet piece 3 is bent. Specific examples thereof include chlorosulfonated polyethylene resin and silicone rubber. In particular, the chlorosulphonated polyethylene-based resin is excellent in flexibility and flame retardancy, has long-term heat resistance at a temperature of 110 ° or higher, and is a ferrite sheet piece 3 using the chlorosulphonated polyethylene-based resin as a binder. It is also easy to select an adhesive for bonding the ferrite sheet piece 3 to the synthetic resin strip sheet 2.

A material having heat resistance and flame retardancy, such as polyvinyl chloride or polycarbonate, is used for the synthetic resin belt-shaped sheet 2, and a flame retardant and other additives are appropriately mixed.

FIG. 2 is a cross-sectional view showing the laminated structure of the magnetic field correcting band-shaped sheet 1, the thickness of which is exaggerated for expression.
In the figure, 3a is an adhesive layer for attaching the ferrite sheet piece 3 to the synthetic resin strip 2, and in this embodiment, an acrylic adhesive is used. The acrylic adhesive has excellent heat resistance, and also has good adhesiveness to the synthetic resin belt-like sheet 2 made of the above-mentioned material and the ferrite sheet piece 3 using the chlorosulfonated polyethylene-based resin. As the adhesive, epoxy-based or rubber-based adhesive can be used in addition to acrylic-based adhesive.

As the pasting means 4, a double-sided adhesive tape is used as in the conventional case. The double-sided adhesive tape has a structure in which a release paper 4d is laminated on the adhesive layer 4a, 4c laminated on both sides of an elastic body 4b such as a sponge base material. The same adhesive as the adhesive layer 3a can be used for the pressure-sensitive adhesive layers 4a and 4c, or another material can be used. In some cases, no base material is provided, or another sticking means is used. In the example shown in the figure, the release paper 4d is set longer than the elastic body 4b so that the release paper 4d can be easily peeled off.

Various procedures can be considered as the procedure for producing the magnetic field correcting strip-shaped sheet 1. For example, as shown in FIG. 3, a ferrite powder-containing resin tape 3A is laminated on one end side in the width direction of a large-sized synthetic resin sheet 2A with an adhesive layer 3a interposed therebetween, and a double-sided adhesive tape 4A is formed on the other end side, respectively. After laminating to obtain a large-sized laminated sheet body, the large-sized laminated sheet body is cut into strip-shaped sheets having a predetermined width.

[0022]

EFFECTS OF THE INVENTION In the magnetic-field-correcting strip-shaped sheet of the deflection yoke of the present invention, since the heat-resistant synthetic resin used for the ferrite powder-containing resin has a rubber hardness of 55 to 90 and an elongation of 50 to 200%, the ferrite powder is 80 to 80%. Molding is possible even when compounded at about 90% by weight, and the flexibility after molding is maintained, and the high permeability of ferrite powder allows the permeability μ to be 10 to 2 without increasing the thickness of the ferrite sheet piece.
It can be increased to a range of 0, and a sufficient magnetic field correction effect can be obtained even if the width of the ferrite sheet piece is set to an extremely narrow width of 0.5 mm to 6.0 mm. Since the ferrite sheet piece of this magnetic field correction strip-shaped sheet has a narrow width and a sufficient magnetic permeability μ, it is possible to locally correct the magnetic field only at the correction target portion without disturbing the magnetic field other than the correction target. it can.

When a chlorosulphonated polyethylene-based resin is used as the heat-resistant synthetic resin as described in claim 2, the chlorosulphonated polyethylene-based resin can be highly filled with ferrite powder, and the ferrite powder blended after the filling is possible. The flexibility of the resin is also satisfactory, and it is possible to exhibit flame resistance and sufficient long-term heat resistance.

When an acrylic adhesive is selected as the adhesive for adhering the synthetic resin strip-shaped sheet and the ferrite sheet piece as described in claim 3, since the adhesive itself has excellent heat resistance, the deflection It is possible to maintain a predetermined sticking posture for a long period of time without deterioration of the adhesive performance due to the temperature rise of the yoke.

[Brief description of drawings]

FIG. 1 is a perspective view showing the outer appearance of a magnetic field correcting strip-shaped sheet of the present invention.

FIG. 2 is a cross-sectional view showing a laminated structure of the magnetic field correction strip-shaped sheets.

FIG. 3 is an explanatory diagram showing an example of a procedure for creating a magnetic field correction strip-shaped sheet.

FIG. 4 is a perspective view showing a state in which a ferrite powder-containing resin small piece is attached to the inner surface of the deflection yoke.

FIG. 5 is a perspective view showing a conventional magnetic field correcting strip-shaped sheet.

6A and 6B are cross-sectional explanatory views showing a state in which a magnetic field correction belt-like sheet is set in the gap between the cathode ray tube neck portion and the deflection yoke.

FIG. 7 is a cross-sectional view of a main part of a conventional magnetic field correction strip-shaped sheet.

FIG. 8 is a cross-sectional view of a main part of a conventional strip sheet for magnetic field correction.

[Explanation of symbols]

A deflection yoke B cathode ray tube 1 magnetic field correction strip 2 synthetic resin strip 2A synthetic resin sheet 3 ferrite sheet piece 3A ferrite powder mixed resin tape 3a adhesive layer 4 sticking means 4a adhesive layer 4b elastic body 4c adhesive Agent layer 4d Release paper a Magnetic field correction strip sheet b Synthetic resin strip sheet c Ferrite sheet piece d Adhesion means d1 Adhesive layer d2 Sponge base material d3 Adhesive layer d4 Release paper f Ferrite powder compound resin pieces

Claims (3)

[Claims] 1. A small piece made of a ferrite powder-containing resin is attached to one end in the longitudinal direction of an elastically deformable synthetic resin band-shaped sheet by an adhesive, and another end is provided with a sticking means to the inner surface of a deflection yoke or a cathode ray tube wall. A strip-shaped sheet for magnetic field correction of a deflection yoke, which is provided and inserted in a gap between the deflection yoke mounted on the cathode ray tube and the cathode ray tube and fixed by the attaching means, which is a heat-resistant synthetic resin used as a resin containing ferrite powder. Has a rubber hardness of 55 to 90 and an elongation of 50 to 200%, and the compounding amount of the ferrite powder in the ferrite powder compounding resin is 80 to
A strip-shaped sheet for magnetic field correction of a deflection yoke, which is 90% by weight, the width of the ferrite powder-containing resin piece is 2.5 mm to 6.0 mm, and the magnetic permeability μ is 10 to 20. 2. A strip-shaped sheet for magnetic field correction of a deflection yoke according to claim 1, wherein a chlorosulfonated polyethylene resin is used as a synthetic resin used for the ferrite powder-containing resin. 3. The magnetic-field-correcting strip-shaped sheet for a deflection yoke according to claim 1, wherein an acrylic adhesive is used as an adhesive for adhering the synthetic resin strip-shaped sheet and the ferrite powder-containing resin small piece.