JPH11260288A - Deflection yoke and cathode-ray tube equipped with the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent a bar magnet from coming off from a pocket without using a sticking means such as adhesive or the like. SOLUTION: In a deflection yoke composed by storing and retaining a bar magnet in a pocket of a resin cover to be installed in a horizontal deflection coil assembly, elastic presser pieces 17 are formed at both ends of a box-shaped pocket 11, having an insertion hole 13 into which the bar magnet 12 is inserted. Then, the play of the bar magnet 12 in the pocket 11 is prevented by bringing the elastic presser pieces 17 into press contact with the end sides 12a of the bar magnet 12, and the elastic presser pieces 17 are allowed to function as magnet slip-off prevention stoppers by installing, at the insertion hole 13 side of the press contact part, top parts 17b of the elastic presser pieces 17 protrusively inward further than the end sides 12a of the bar magnet 12.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a cathode ray tube,
In particular, it relates to a deflection yoke for deflecting an electron beam emitted from an electron gun by a magnetic field.

[0002]

2. Description of the Related Art In general, a cathode ray tube (CRT) used for a television picture tube, a computer display, or the like, incorporates a deflection yoke for deflecting an electron beam emitted from an electron gun by a magnetic field.

[0003] This deflection yoke has a horizontal deflection coil and a vertical deflection coil for generating a deflection magnetic field on the trajectory of the electron beam. In the cathode ray tube having the deflection yoke, by driving the horizontal deflection coil and the vertical deflection coil, the electron beam emitted from the electron gun is electromagnetically deflected, and the electron beam is raster-scanned. That is, when the electron beam emitted from the electron gun passes through the deflection magnetic field by the deflection yoke, the scanning trajectory is bent up and down and left and right of the cathode ray tube, and is deflected. Face).

Further, this type of deflection yoke is provided with a bar magnet for correcting a pin-shaped image distortion (hereinafter referred to as vertical pin distortion) generated in a vertical direction of a display screen when a cylindrical screen shape is adopted. There is something. In this case, the mounting state of the bar magnet is such that a box-shaped pocket is integrally formed (molded) on a resin cover mounted on the large-diameter opening side of the horizontal deflection coil assembly having a substantially conical cylindrical shape. Holds and holds a bar magnet.

FIG. 4 is a sectional view showing a structure of a pocket provided in a resin cover of the deflection yoke and a support structure of a bar magnet in the pocket. First, the bar magnet 30 for correcting vertical pin distortion is a square column permanent magnet,
The insertion slot 31 corresponding to this magnet shape is the pocket 3
2 is formed.

The pocket 32 has an abutting wall 33 against which the bar magnet 30 is abutted when the bar magnet 30 is inserted from the insertion opening 31, and a pair of side walls rising from the long side of the abutting wall 33. 34 and a pair of end walls 35 rising from the short side of the abutting wall 33 to form a box shape.

A plurality of ridges 34 a are formed inside the pair of side walls 34, and the ridges 34 a are pressed against both side surfaces of the bar magnet 30. Also,
The inner sides of the pair of end walls 35 are formed to project in a mountain shape, and their protruding end portions are pressed against both end surfaces of the bar magnet 30. Thus, both sides and both end faces of the bar magnet 30 are always in a state where a pressure (a pinching pressure) is applied, and the bar magnet 30 is housed and held in the pocket 32 in this state.

[0008]

By the way, when assembling the deflection yoke, the pocket 32 of the resin cover is required.
The resin cover is mounted on the horizontal deflection coil assembly in a state where the bar magnet 30 is accommodated. At this time,
During the handling of parts, vibration or impact may be applied to the resin cover. In such a case, the conventional deflection yoke has a fixed structure in which both end surfaces and both side surfaces of the bar magnet 30 are sandwiched between the pockets 32, so that when the vibration or shock is applied from the outside as described above, There is a risk that the bar magnet 30 will play in the inside of the pocket 32 or the bar magnet 30 may come off from the pocket 32 in some cases.

As a measure against this, for example, a bar magnet 30
May be fixed to the pocket 32 using an adhesive or the like, but in such a case, additional work and management man-hours associated with the use of the adhesive are increased, which leads to an increase in cost.

SUMMARY OF THE INVENTION The present invention has been made to solve the above problems, and a main object of the present invention is to provide a deflection yoke which can reliably prevent a bar magnet from coming off a pocket without using fixing means such as an adhesive. To provide.

[0011]

SUMMARY OF THE INVENTION The present invention has been made to achieve the above-mentioned object, and has a substantially conical cylindrical horizontal deflection coil assembly mounted on a large-diameter opening side of the horizontal deflection coil assembly. In a deflection yoke having a substantially ring-shaped resin cover and containing and holding a square pole magnet in a pocket integrally formed with the resin cover, the pocket has a rectangular shape in which the bar magnet is inserted. It has a box-shaped structure having an insertion port, and has elastic pressing pieces at both ends in the longitudinal direction of the pocket. Then, in a state where the bar magnet is accommodated in the pocket, the elastic pressing piece is pressed against the end side of the bar magnet arranged on the insertion port side, and one of the elastic pressing pieces is pressed at the insertion port side of the pressing portion. The part is arranged so as to protrude inward of the pocket from the end side of the bar magnet.

In the deflection yoke having the above structure,
When the bar magnet is housed in the pocket of the resin cover, the elastic pressing piece presses against the edge of the bar magnet, and the bar magnet moves in the long side direction of the pocket and the bar magnet moves to the pocket insertion side. Movement is regulated together. Also, with the elastic holding piece pressed against the end side of the bar magnet, a part of the elastic holding piece is protruded inside the pocket from the end side of the bar magnet,
The elastic pressing piece comes to function as a stopper for retaining the magnet.

[0013]

Embodiments of the present invention will be described below in detail with reference to the drawings. FIG. 1 is an exploded perspective view showing a structural example of a deflection yoke to which the present invention is applied.
In FIG. 1, a deflection yoke 1 includes a horizontal deflection coil assembly 2, a vertical deflection coil assembly 3, a resin front cover 4, a back cover 5, and a purity adjusting magnet 6.

The horizontal deflection coil assembly 2 is formed by integrally connecting horizontal deflection coils 8a and 8b, each having a pair of separators 7a and 7b wound with a magnet wire, and is a substantially conical cylinder in an assembled state. Shape. The vertical deflection coil assembly 3 is formed by integrally connecting vertical deflection coils 10a and 10b in which magnet wires are wound around a pair of cores 9a and 9b, respectively, and also has a substantially conical cylindrical shape in an assembled state. .

The front cover 4 is made of, for example, a mold resin such as polyethylene terephthalate or modified polyphenylene oxide, and is mounted on the large-diameter opening side of the horizontal deflection coil assembly 2 (the lower side in the figure). The front cover 4 is formed in a substantially ring shape corresponding to the opening shape of the horizontal deflection coil assembly 2. A pair of pockets 11, 11 integrally formed with the front cover 4 are provided on the outer peripheral edge of the front cover 4.
A bar magnet (to be described later) for correcting vertical pin distortion is housed and held therein. The back cover 5 is mounted on the small-diameter opening side (upper side in the drawing) of the horizontal deflection coil assembly 2, and the purity adjusting magnet 6 is mounted on the back cover 5.

FIG. 2 is a structural explanatory view of a pocket 11 in the front cover 4 as one embodiment of the deflection yoke according to the present invention. In the drawings, (a) is a front view of the front cover 4, (b) is an enlarged view of the pocket portion A, and (c) is a cross-sectional view of the pocket portion taken along line BB '. First, pocket 1
FIG. 2C shows the rod magnet 12 serving as a housing part for the first magnet 1.
As shown in FIG. 2, a rectangular pole permanent magnet having one end on the N pole and the other end on the S pole is formed in the pocket 11 in a rectangular shape corresponding to the magnet shape.

The pocket 11 is molded integrally with the front cover 4. When the bar magnet 12 is inserted from the insertion opening 13, the pocket 11 collides with the abutting wall 14. A pair of side walls 15 rising from the long side of the abutment wall 14 and a pair of end walls 16 rising from the short side of the abutment wall 14 are formed in a box shape.

Of these, ridges 15a, 15a,... Are formed inside the pair of side walls 15, respectively.
These ridges 15a, 15a,.
From the insertion slot 13 to the abutment wall 14 along the depth direction of the pocket (the vertical direction in FIG. 2C).

On the other hand, a pair of end walls 16 located at both ends of the pocket 11 are cut away from the insertion opening 13 side in the pocket depth direction, with a part of each end wall 16 being cut.
The elastic pressing pieces 17, 17 are integrally formed. Each of the elastic pressing pieces 17, 17 is connected to an end portion of the abutting wall 14 at a root portion (a lower end portion in FIG. 2C), and is in a state where it can slightly swing about the connecting portion as a fulcrum. ing.

Each of the elastic pressing pieces 17, 17 is formed in a substantially mountain-shaped cross section as shown in FIG. 2 (c).
Further, in the longitudinal direction of the pocket 11, the distance L1 between the tops 17a of the elastic pressing pieces 17, 17 is 17
The length is set to be smaller than the longitudinal dimension L2 of the bar magnet 12 (L1 <L2).

In the above configuration, when the bar magnet 12 is housed in the pocket 1 of the front cover 4, the bar magnet 12 is inserted from the direction of the arrow shown in FIG. At this time, while the bar magnet 12 is being inserted, both ends of the magnet are held by the respective elastic pressing pieces 17, 17.
In the vicinity of the tops 17a, 17a. When the bar magnet 12 is further pushed in in this state, the elastic pressing pieces 17, 1 at both ends of the pocket are pressed according to the pushing force.
7 swing outward. As a result, the bar magnet 12 can be pushed into the position indicated by the broken line in FIG.

Thus, the bar magnet 12 is inserted into the pocket 11.
In the state in which the bar magnets 12 are accommodated, as shown in FIG.
In contrast, the tapered surfaces 17b, 1 of the elastic pressing pieces 17, 17
7b are in pressure contact (line contact) from oblique directions.

Under this pressure contact state, the pressing force of each elastic pressing piece 17, 17 is applied to the end side 12 of the bar magnet 12.
By acting on a and 12a, both the movement of the bar magnet 12 in the longitudinal direction of the pocket 11 and the movement of the bar magnet 12 toward the insertion opening 13 of the pocket 11 are restricted. Therefore, even if vibration or shock is applied from the outside,
The rod magnet 12 does not rattle in the pocket 11.

Also, the end side 12a of the bar magnet 12
Insertion opening 13 for press-fitting portion between 12a and elastic pressing pieces 17, 17
On the side (upper side of the figure), each of the elastic pressing pieces 17 and 1
7 are the end sides 1 of the bar magnet 12.
It is arranged in a state protruding inward from the pockets than 2a and 12a. As a result, each of the elastic pressing pieces 17, 17 functions as a stopper for preventing the magnet from coming off.
The rod magnet 12 does not come off the pocket 11.

Further, in the cathode ray tube provided with the deflection yoke 1, since the rod magnet 12 does not rattle or come off in the pocket 11 as described above, even after being provided to a general user as a television or the like. Thus, a desired vertical pin distortion correction effect can be exhibited over a long period of time.

In the above embodiment, the elastic holding pieces 17, 17 at both ends of the pocket 11 have a substantially mountain-shaped cross section.
Each tapered surface 17b, 17b is
The structure in which the end portions 12a of the bar magnet 12 are pressed against the end sides 12a of the bar magnet 12 is, for example, a semicircular shape. Various modifications are conceivable, such as a structure in which the peripheral surface is pressed into contact with the end side 12a of the bar magnet 12 (line contact).

[0027]

As described above, according to the present invention, the elastic holding pieces at both ends of the pocket are pressed against the end sides of the bar magnet, so that the movement of the bar magnet in the longitudinal direction of the pocket and the insertion slot of the pocket are achieved. Since the movement of the bar magnet to the side is both regulated, rattling of the bar magnet in the pocket can be effectively prevented. In addition, since a part of the elastic pressing piece protrudes inward from the end of the bar magnet toward the inside of the pocket, the elastic pressing piece functions as a stopper for retaining the magnet. Even without using any means, it is possible to reliably prevent the bar magnet from coming off the pocket.

[Brief description of the drawings]

FIG. 1 is an exploded perspective view showing a configuration example of a deflection yoke to which the present invention is applied.

FIG. 2 is an explanatory diagram of a structure of a pocket in the embodiment.

FIG. 3 is a cross-sectional view illustrating a rod magnet holding structure according to the embodiment.

FIG. 4 is a cross-sectional view showing a conventional bar magnet holding structure.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Deflection yoke, 2 ... Horizontal deflection coil assembly, 4
... front cover, 11 ... pocket, 12 ... stick magnet, 1
3 ... insertion slot, 17 ... elastic holding piece

Claims (2)

[Claims] 1. A horizontal deflection coil assembly having a substantially conical cylindrical shape, and a substantially ring-shaped resin cover mounted on the large-diameter opening side of the horizontal deflection coil assembly, and are integrally formed with the resin cover. In a deflection yoke in which a rectangular pole magnet is housed and held in a pocket, the pocket has a box-shaped structure having a rectangular insertion opening into which the bar magnet is inserted, and elastically provided at both ends in the longitudinal direction of the pocket. A presser piece; presses the elastic presser piece against an end side of the bar magnet disposed on the insertion port side in a state where the bar magnet is housed in the pocket; and 3. The deflection yoke according to claim 1, wherein a part of the elastic pressing piece is arranged to protrude inward of the pocket from an end of the bar magnet. 2. A cathode ray tube comprising the deflection yoke according to claim 1.