JPH05325789A - Fitting method for magnetic field correcting sheet of deflection yoke - Google Patents

Abstract

PURPOSE:To provide a fitting method of a magnetic field correcting sheet facilitating the fitting of a deflection yoke to a curved face and capable of maintaining the magnetic field correction effect over long years by selecting and using a more proper raw material for the constituting material of the magnetic field correcting sheet. CONSTITUTION:A sheet body 1 made of magnetic material-containing resin is stuck along the curved shape of the surface of the coil (a) of a deflection yoke A, and an acetate tape 2 is overlapped and stuck, on it. The sheet body 1 is stuck along the surface of the coil (a) via an adhesive layer 1a on the back face of the sheet body 1 and an adhesive layer 2a on the back face of the acetate tape 2. The soft ferrite powder is dispersed and combined in a synthetic resin binder to form the magnetic field correcting sheet body 1. The binder is made of a material having curvable plasticity for the initial characteristic at the ordinary temperature after molding and losing plasticity when the preset cumulative time elapses at the high temperature of 100 deg.C or above, e.g. styrene thermoplastic elastomer mixed with polymethyl pentene.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for mounting a magnetic field correction sheet for a deflection yoke, and more specifically, it is easy to mount on a curved surface, and after mounting, the curved shape along the bonding surface is semi-permanent. The present invention relates to a method of mounting a magnetic field correction sheet that can be held on a substrate.

[0002]

2. Description of the Related Art A deflection yoke mounted on a cathode ray tube used for a television, a CRT display or the like uses a magnetic field correcting sheet for the purpose of finely adjusting the magnetic field. FIG. 6 shows this state, in which the sheet body 1 is attached to the winding a of the deflection yoke A. The sheet body 1 is a magnetic material-containing resin sheet formed by dispersing and blending soft ferrite powder in a synthetic resin, and the sheet body 1 is attached along the curved surface of the winding a by the adhesive applied to the back surface. Has been. And the sheet body 1
An acetate tape 2 coated with an adhesive is further laminated from above to the back surface to prevent the sheet body 1 from falling off.

[0003]

Conventionally, polymethylpentene and polypropylene have been mainly used as a binder for such a sheet body 1, but since these resins are hard at room temperature and have a strong elastic restoring force, It is difficult to attach the magnetic field correction sheet using these binders along the curved surface of the deflection yoke. Although the curved shape can be maintained by the adhesive force of the pressure-sensitive adhesive immediately after the sticking, the magnetic field correcting sheet itself tends to be restored to a linear cross section with the passage of time.

As shown in FIGS. 7 and 8, an acetate tape 2 is laminated on the magnetic field correction sheet 1 to prevent the tape from falling off. However, when the receiver is used for a long time, the adhesive tape on the back surface of the acetate tape 2 is adhered. As the adhesive strength of the agent 2a is reduced, the phenomenon that the acetate tape 2 is turned up occurs as shown in FIG.
The sheet body 1 restored to the linear cross section cannot be held on the surface of the winding, which may cause the sheet body 1 to drop off. Even if the sheet body 1 does not fall off, the magnetic field correction effect may not function because the sheet body 1 is separated from the winding surface.

The present invention has been made in view of the above circumstances, and it is easy to attach the magnetic field correction sheet to the curved surface of the deflection yoke, and after the attachment, the curved shape along the attachment surface is semi-permanent. It is intended to provide a method for mounting a magnetic field correction sheet that can be held at the same time and can maintain the magnetic field correction effect at the time of mounting for many years.

[0006]

In order to solve such a problem, as a material for forming the magnetic field correction sheet, the material has the flexibility to follow a curved surface at the time of mounting, and the curved shape after mounting. The present invention has been completed based on the idea that a material having a hardness that can maintain the above can be selected, and that the above-mentioned characteristic change of the material can be utilized by the amount of heat constantly acting in the use process of the receiver. It is a thing.

The present invention, which has solved the above-mentioned problems, has a plasticity such that the initial characteristics after molding at room temperature can be curved and
A material that loses plasticity when a predetermined cumulative time has passed under a high temperature of 00 ° C. or more is used as a binder,
Using the flexibility that is the initial characteristic at room temperature, the magnetic field correction sheet is pasted along the curved surface of the deflection yoke, and after mounting, it becomes the magnetic field correction sheet during the process in which the receiver of the receiver operates the receiver. It is characterized in that the shape along the curved surface of the deflection yoke is maintained by curing the magnetic field correction sheet by the amount of heat applied. For example, as the binder, it is considered to use a synthetic resin that loses plasticity when cumulatively heated for 300 hours or more in a temperature environment of 120 ° C. Specifically, a styrene-based resin is used with respect to 100 parts by weight of polymethylpentene. Thermoplastic elastomer 70-1
It is possible to use the one set to 00 parts by weight.

[0008]

Like the conventional magnetic field correction sheet, such a magnetic field correction sheet is attached along the curved surface of the deflection yoke to correct the magnetic field, and then the acetate tape is overlaid to prevent the sheet from falling off. . Since the magnetic field correction sheet uses a binder having sufficient plasticity for initial properties at room temperature, it can be easily attached to a curved surface. The image receiver in which the magnetic field of the deflection yoke is corrected in this manner is shipped from the factory and used by consumers. The deflection yoke of the receiver in use reaches a high temperature of 100 ° C. or higher, and the magnetic field correction sheet is exposed to such a high temperature state for a long period of time or intermittently, and the properties of the binder change and harden. The magnetic field correction sheet is fixed while maintaining its curved shape. The magnetic field correction sheet whose curved shape is fixed in this way can be reliably retained on the winding surface, and will not fall off even if the adhesive of the acetate tape deteriorates, and Since the close contact state can be maintained, the magnetic field correction effect does not change and the magnetic field adjustment effect can be continued for many years.

[0009]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The details of the present invention will be described below with reference to illustrated embodiments. FIG. 1 shows one embodiment of the magnetic field correction sheet of the present invention. The magnetic field correction sheet has a structure in which an adhesive layer 1a and a release paper 1b are laminated on the back surface of a sheet body 1 made of a magnetic material-containing resin. Although the example shown in the drawing shows a single sheet body, normally, a large number of sheet bodies 1 are supplied in a state in which they are arranged vertically and horizontally via a breaking groove.

The sheet body 1 is formed by a material in which soft ferrite powder such as manganese zinc ferrite, nickel zinc ferrite or magnesium ferrite is dispersed and blended in a synthetic resin binder, and the present invention is synthesized in such a sheet body 1. It is characterized in that a resin binder having a specific property is selected and its thermal property is utilized.

The synthetic resin binder selected in the present invention has a plasticity capable of bending at room temperature after molding and loses plasticity after a predetermined cumulative time has passed under a high temperature condition of 100 ° C. or higher. Anything will do.
Synthetic resin binders that meet such conditions include, for example, polymethylpentene mixed with styrene-based thermoplastic elastomer, and examples of the styrene-based thermoplastic elastomer include those of Kraton G (manufactured by Shell Japan Co., Ltd.). It is possible to use those distributed under the product name.

The styrene-based thermoplastic elastomer plays the role of a softening agent and exerts flexibility as an initial characteristic at room temperature, which is required at the time of mounting, and the styrene-based thermoplastic elastomer is polymethylpentene. Mixing ratio is polymethylpentene 10
70 parts by weight of styrene thermoplastic elastomer 70
It is preferable to set to 100 parts by weight. If the compounding ratio of the styrene-based thermoplastic elastomer is less than 70 parts by weight, the tensile elongation at break is insufficient, while if it exceeds 100 parts by weight, it becomes unsuitable for injection molding. However, if a molding means other than injection molding, for example, extrusion molding or roll molding is adopted, the upper limit of the compounding ratio of the styrene-based thermoplastic elastomer is not particularly limited, and the binder can be used without using polymethylpentene. It is also possible to make up entirely of styrene thermoplastic elastomer. Styrenic thermoplastic elastomers have heat resistance comparable to that of polymethylpentene, so even when the total amount of binder is styrene thermoplastic elastomer, it has excellent heat resistance life and more flexible initial temperature characteristics when mounted. A magnetic field correction sheet can be obtained. Needless to say, the binder may be blended with an appropriate amount of a conventionally known additive such as a stabilizer.

As the synthetic resin binder, in addition to the above, a mixture of silicon ethylene propylene and a styrene thermoplastic elastomer may be used. Further, polyvinyl chloride added with a plasticizer also has the property of a synthetic resin expected by the present invention that the initial properties at room temperature are soft and become hard when exposed to a high temperature condition for a predetermined accumulation time or more, Vinyl added with a plasticizer is not suitable for high temperature environment because its insulating property remarkably deteriorates.

These synthetic resins, which are thermoplastic resins, become hard when exposed to high temperature conditions due to heat generation of the winding of the deflection yoke during continuous or intermittent accumulation of a predetermined time or more. The mechanism by which the curved shape is fixed is presumed to be due to the following reasons. That is, the exothermic temperature of the deflection yoke is usually in the range of about 120 ° C. to 180 ° C., which is lower than the melting point of each of the above synthetic resins, and if it is within this range, it should exhibit plasticity when heated. However, if this state continues for a long time, or if the cumulative time of being repeatedly exposed to high temperature for a certain period of time exceeds a predetermined time, the crosslinking reaction proceeds due to the thermal decomposition action of the resin, and the resin is It is presumed that irreversible hardening phenomenon occurs as a result of alteration.

When the time when the curing phenomenon actually occurs was measured using a binder in which styrene thermoplastic elastomer was added to polymethylpentene, the above curing phenomenon occurred at the stage of continuous heating at a temperature of 120 ° C. for about 300 hours. It was confirmed to do. This 300 hours can be used according to the actual usage of the receiver in the home.
It is a time period of about 2 months to half a year, and it can be seen that in a normal state of use of the image receiver, the magnetic field correction sheet is cured while maintaining the curved shape after the lapse of the above period.

FIGS. 2 and 3 show how the magnetic field correcting sheet is attached to the curved surface of the deflection yoke A. As in the conventional method, the sheet body 1 is attached along the curved shape of the winding surface. The figure shows a state in which the acetate tape 2 is laminated and attached. FIG. 4 shows the state immediately after mounting, and the adhesive 1a on the back of the sheet body and the adhesive 2a on the back of the acetate tape are shown.
Shows that the sheet body 1 is attached to the winding surface. FIG. 5 shows a state in which the acetate tape 2 is lifted up during a long use of the receiver. According to the present invention, even if the acetate tape 2 floats up, the sheet body 1
Since the sheet body 1 is hardened while maintaining its curved shape, the sheet body 1 does not drop off from the winding surface, and a gap is generated between the sheet body 1 and the winding surface, which disturbs the magnetic field correction effect. It does not happen.

[0017]

According to the present invention, the magnetic field correction sheet can be easily mounted along the curved shape of the deflection yoke, and after the mounting, the curved shape is maintained by the heat generated by the deflection yoke during the process of using the image receiver. Since it can be hardened, the fixed state on the winding surface can be reliably maintained. Therefore, even after many years of use, the magnetic field correction sheet will not fall off or the magnetic field correction effect will not be affected. Further, according to the present invention, since the characteristics of the synthetic resin binder are changed by utilizing the heat generated by the deflection yoke in the process of use, it is not necessary to change the work of attaching the magnetic field correction sheet to the deflection yoke. The conventional process can be directly followed.

[Brief description of drawings]

FIG. 1 is a perspective view showing a magnetic field correction sheet.

FIG. 2 is an explanatory diagram showing a state in which a magnetic field correction sheet is attached to a winding surface.

[Fig. 3] On the magnetic field correction sheet attached to the winding surface,
Explanatory drawing showing a state of accumulating acetate tapes

FIG. 4 is an explanatory view showing a state in which a magnetic field correction sheet and an acetate tape are attached to the winding surface.

FIG. 5 is an explanatory view showing a state where the acetate tape is lifted up due to aging.

FIG. 6 is an explanatory perspective view showing a state in which a magnetic field correction sheet and an acetate tape are attached to the inner surface of the deflection yoke.

FIG. 7 is an explanatory view showing a state in which an acetate tape is overlaid on a magnetic field correction sheet attached on the surface of a winding wire.

FIG. 8 is an explanatory view showing a state in which a magnetic field correction sheet and an acetate tape are attached to the winding surface.

FIG. 9 is an explanatory view showing a state in which the magnetic field correction sheet attached to the surface of the winding is lifted by elastic restoring force.

[Explanation of symbols]

 A deflection yoke a winding 1 sheet body 1a adhesive 1b release paper 2 acetate tape 2a adhesive

Claims (3)

[Claims] 1. A technique for correcting a magnetic field of a deflection yoke by adhering a magnetic field correction sheet formed by dispersing and blending soft ferrite powder in a synthetic resin binder onto the winding surface of the deflection yoke, at room temperature after molding. A material that has a bendable plasticity as the initial characteristic and loses the plasticity after a predetermined cumulative time has passed at a high temperature of 100 ° C. or more is used as a binder, and the flexibility that is the initial characteristic at room temperature is used. The magnetic field correction sheet is attached along the curved surface of the deflection yoke, and after mounting, the magnetic field correction sheet is cured by the amount of heat applied to the magnetic field correction sheet during the process in which the receiver of the receiver operates the receiver. Thus, the method for mounting the magnetic field correction sheet of the deflection yoke, which maintains the shape along the curved surface of the deflection yoke. 2. The method for mounting a magnetic field correction sheet of a deflection yoke according to claim 1, wherein a binder that loses plasticity when cumulatively heated for 300 hours or more in a temperature environment of 120 ° C. is used. 3. A binder comprising 70 to 100 parts by weight of a styrene-based thermoplastic elastomer mixed with 100 parts by weight of polymethylpentene as a binder.
A method for mounting a magnetic field correction sheet for a deflection yoke as described above.