JPH11233047A - Deflecting yoke and cathode-ray tube type display apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To suppress temperature increase of a deflecting yoke by installing a heat releasing mechanism while being held and brought into contact with a coil in a part where the absolute value of the density of magnetic fluxes leaking to an outer space from a horizontally deflecting coil is lower than those of other parts. SOLUTION: A holding member 9 is installed in a region where the absolute value of the density of magnetic fluxes leaking to an outer space from a horizontally deflecting coil 2 is lower than those in other regions, in other words in a region where the polarity of the magnetic fluxes is inverted and a heat releasing mechanism is installed in the holding member 9. Consequently, since the density of magnetic fluxes of a magnetic field leaking out of the horizontally deflecting coil affecting the holding member 9 is suppressed, the generation quantity of Joule's heat due to eddy current can be significantly suppressed. The heat generated in the horizontally deflecting coil 2 is highly efficiently transmitted to the heat releasing mechanism 8 and released to air, so that the operation temperature in the neck part of the horizontally deflecting coil 2 where the temperature increases highest in the deflecting yoke 1 can be lowered. Moreover, in the case the holding member 9 and the heat releasing mechanism 8 are integrally made of an aluminum or the like, the operation temperature of the neck part can further be lowered.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a deflection yoke and a cathode ray tube display device, and more particularly, to a deflection yoke having a heat radiation mechanism for reducing a temperature rise of a deflection yoke for deflecting an electron beam up, down, left and right, and comprising the deflection yoke. The present invention relates to a cathode ray tube display device.

[0002]

2. Description of the Related Art In recent cathode ray tube display devices, there is an increasing demand for a large screen and a high resolution of a displayed image. For the latter, means for increasing the horizontal deflection frequency of an electron beam is used. However, in addition to the increase in deflection power due to the enlargement of the screen, when the horizontal deflection frequency is increased and a high-frequency deflection current is passed through the horizontal deflection coil of the deflection yoke, the high-frequency loss of the coil and the loss of the magnetic core increase sharply. However, there arises a problem that the temperature rise of the deflection yoke rapidly increases.

Degradation of the quality of reproduced images is likely to occur due to a rise in the temperature of the deflection yoke, and furthermore, reliability such as deformation and durability of resin parts and the like constituting the deflection yoke is reduced.
There was also a problem with life.

In order to reduce the temperature rise of the deflection yoke,
A so-called litz wire in which a number of thin wires are wound in parallel with a coil material is used to reduce high-frequency loss in a frequency region of 100 kHz or less. On the other hand, there has been known a technique for efficiently transferring heat generated in each part of the deflection yoke to surrounding air during operation of the deflection yoke and radiating the heat to reduce a rise in temperature.

The first prior art is disclosed in Japanese Utility Model Laid-Open Publication No. 61-13105.
As described in Japanese Patent Application Laid-Open No. 4 (1993) -174, the surface of the magnetic core of the deflection yoke is provided with irregularities to increase the contact area with air to radiate heat. As described in Japanese Patent Application Laid-Open Publication No. H11-260, heat is dissipated by providing a radiation fin on the outer wall surface of the magnetic core of the deflection yoke.

[0006]

However, the first prior art has a problem that the heat radiation effect is small because the magnetic core having a small thermal conductivity is provided with irregularities for heat radiation.
In addition, there is a problem that the productivity of the magnetic core having irregularities is deteriorated.

In the second prior art, the amount of heat transfer from the horizontal deflection coil having the largest temperature rise in the deflection yoke to the magnetic core is small, and the thermal conductivity of the magnetic core material is small as described above. Therefore, there is a problem that the heat radiation effect of the horizontal deflection coil is small.

SUMMARY OF THE INVENTION In view of the above problems, an object of the present invention is to dissipate the heat generated by a horizontal deflection coil having the largest temperature rise in a deflection yoke into the air with high efficiency, thereby greatly reducing the temperature rise of the deflection yoke. It is intended to provide a technology for reducing the amount.

[0009]

In order to achieve the above object, the present invention reduces heat generation due to eddy current generated in the heat radiating mechanism by providing a heat radiating mechanism in contact with a plurality of horizontal deflection coils. Also, by using a high thermal conductivity high resistivity material or a high thermal conductivity inorganic insulator material for the holding part where the heat radiating mechanism contacts the horizontal deflection coil, heat generation of the holding part due to eddy current is greatly reduced, Means is provided for transmitting the amount of heat generated from the horizontal deflection coil to the heat radiation mechanism with high efficiency.

[0010]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, a first embodiment of the present invention will be described with reference to FIGS. 1 and 2 are a sectional view and a side view showing a main part of a deflection yoke according to the present invention. In the drawings, the same components are denoted by the same reference numerals.

The deflection yoke 1 of the present invention has a horizontal deflection coil 2 (2) through which a high-frequency deflection current of several tens kHz to one hundred and several tens kHz flows.
R, 2L), 21 (21R, 21L), a vertical deflection coil 4, 41 through which a low-frequency deflection current of about 100 Hz flows, and a resin made of resin that electrically insulates the horizontal deflection coils 2, 21 from the vertical deflection coils 4, 41. , A magnetic core 5 made of a ferrite material having a high magnetic permeability, a support 6 for fixing one end of the separator 3 to a neck tube (not shown) of a cathode ray tube, a tightening band 7 and two horizontal deflection coils 2 And 21 and a radiating mechanism (radiating fin) 8 for transmitting the heat generated by the horizontal deflection coils 2 and 21 to the air.

The holding portion 9 of this embodiment is made of a metal material having a high thermal conductivity, for example, an inexpensive aluminum material, which is in contact with and fixed to the two horizontal deflection coils 2 and 21. Although not shown in the drawing, the space between the heat dissipating mechanism 8 and the holder 9 and the holder 9
The horizontal deflection coils 2 and 21 are in close contact with the horizontal deflection coils 2 and 21 through silicon grease, high thermal conductivity silicone gel or a high thermal conductivity heat radiation sheet to reduce the thermal resistance of the contact surface. It may be fixed. or,
By using an epoxy adhesive having a high thermal conductivity, the thermal resistance of the contact portion can be reduced and the heat radiating mechanism 8 and the holding portion 9 and the holding portion 9 can be reduced.
Can be attached to the horizontal coil and fixed at the same time. In addition,
FIG. 2 does not show the heat radiating mechanism 8 and the holding unit 9 to show the horizontal deflection coils 2R and 21R.

FIG. 3 is a front view of the horizontal deflection coils 2 and 21, and FIG. 4 is a plan view of the horizontal deflection coil 2. The coil 2 generates a horizontal deflection magnetic field (not shown).
R and 2L, front and rear coil crossover portions 2F and 2B, and a window portion 2W where there is no coil wire. Similarly coil 2
Reference numeral 1 denotes 21R, 21L and the like for generating a horizontal deflection magnetic field. As shown in FIG. 3, the directions of the currents flowing through the coils 2R, 2L, 21R, 21L are the same in 2R and 21R, and the same in 2L and 21L. 21 shows the results of measuring the magnetic flux density B of a magnetic field leaking vertically from the outer wall surface of the coil along the outer wall surface of the coil 21.

The magnetic flux density B leaking from the horizontal deflection coils 2 and 21 to the external space is θ (the X axis in FIG. 3 is set to θ = 0 °).
However, the polarity is inverted every 180 degrees. On the other hand, since the holding portion 9 made of a metal material exists in the leakage magnetic field, the holding portion 9
Causes eddy currents to flow, generating Joule heat.

The Joule heat caused by the eddy current is the intensity of the magnetic flux density B and the rate of change of the magnetic flux density f (horizontal deflection frequency)
Is proportional to the reciprocal of the volume resistivity ρ of the material. Therefore, as the absolute value of the magnetic flux density B increases, the temperature rise of the holding unit 9 increases. Therefore, the holding unit 9 is disposed in a region where the absolute value of the magnetic flux density B shown in FIG. 5 is smaller than other portions, that is, in a region where the polarity of the magnetic flux density B is reversed (the portion indicated by a double arrow in FIG. 5).

For example, in the present embodiment, θ in FIG.
The holding portions 9 made of aluminum are installed in a region from +25 degrees to +25 degrees and in a region from +155 degrees to +205 degrees, and the heat radiation mechanism 8 is attached to each of them. By arranging the holding portion 9 in such an area, the magnetic flux density of the magnetic field leaking from the horizontal deflection coils 2 and 21 acting on the holding portion 9 can be reduced, and the generation amount of Joule heat due to the eddy current can be largely suppressed. it can. As a result, the heat generated in the horizontal deflection coils 2 and 21 can be transmitted to the heat radiating mechanism 8 with high efficiency and can be radiated into the air, so that the neck of the horizontal deflection coils 2 and 21 having the highest temperature rise in the deflection yoke 1. The operating temperature of the unit can be greatly reduced.

Since the operation is the same as that described above, a description thereof will be omitted. However, by using an integrally manufactured holding portion 9 and heat radiation mechanism 8 made of a material such as aluminum, the deflection yoke 1 Thus, the operating temperature of the neck portions of the horizontal deflection coils 2 and 21 having the highest temperature rise can be greatly reduced.

FIG. 6 shows a second embodiment of the present invention, in which a holding section and a heat radiating section using a high resistivity material having a high thermal conductivity or an inorganic insulator material having a high thermal conductivity are integrated. The radiating mechanism 80 is used. The aluminum material used in the first embodiment (volume resistivity ρｍ2.8E-8 [Ωm],
Here, E indicates a power of 10), and a material having a high thermal conductivity and a high resistivity, for example, an alumina porcelain material (volume resistivity ρ ≒ 1E12 [Ωm]) has a very high volume resistivity ρ. As a result, the heat generation amount (∝1 / ρ) of the heat dissipation mechanism 80 due to Joule heat caused by the eddy current due to the leakage magnetic field can be significantly suppressed. Therefore, the heat generated in the horizontal deflection coils 2 and 21 can be transmitted to the heat radiating mechanism 80 with high efficiency and can be radiated into the air, so that the neck of the horizontal deflection coils 2 and 21 having the highest temperature rise in the deflection yoke 1. Operating temperature can be greatly reduced.

FIG. 7 shows a third embodiment of the present invention, in which a high resistivity material having a high thermal conductivity or an inorganic insulator material having a high thermal conductivity is used as the holding portion 90, and a heat radiating member made of aluminum is used. Used in combination with mechanism 8. As in the second embodiment, by using a material having a high thermal conductivity and a high resistivity or a material of an inorganic insulator as the holding portion 90, heat generation of the holding portion 90 due to an eddy current due to a leakage magnetic field is reduced. Can be reduced to almost zero. Therefore, the horizontal deflection coils 2, 2
1. The heat generated in 1 can be transferred to the heat dissipation mechanism 80 with high efficiency,
Since the heat can be radiated into the air, the operating temperature of the neck portions of the horizontal deflection coils 2 and 21 having the highest temperature rise in the deflection yoke 1 can be greatly reduced.

The second and third embodiments are as follows.
Since the heat radiation mechanism 80 and the holding unit 90 do not generate heat due to the leakage magnetic field, compared to the first embodiment, the heat radiation mechanism 80
Also, there is an advantage that the degree of freedom of the mounting position of the holding portion 90 can be increased.

Note that the horizontal deflection coils 2 and 21 and the vertical deflection coils 4 and 41 to which the present invention is applied are not limited to the shapes shown in the figure, but are applied to coils (for example, 2R and 2L) that generate a deflection magnetic field. Transfer section (for example, 2
It goes without saying that B) may have a bent shape.

[0022]

As described above, according to the present invention,
Since the heat generated by the holding section due to the eddy current caused by the leakage magnetic field from the deflection yoke can be reduced, the temperature rise of the deflection yoke can be increased by directly contacting the horizontal deflection coil section having the highest temperature rise and by providing a heat radiation mechanism. Efficiency can be greatly reduced. As a result, characteristic fluctuations, performance deterioration and reliability deterioration due to temperature rise of the deflection yoke do not occur during high frequency operation or large current driving, so that high-quality images can be reproduced, and a highly reliable deflection yoke and There is an effect that a cathode ray tube display device can be realized.

[Brief description of the drawings]

FIG. 1 is a sectional view showing a configuration of a deflection yoke according to a first embodiment of the present invention.

FIG. 2 is a diagram showing a configuration of a deflection yoke according to the first embodiment of the present invention.

FIG. 3 is a diagram showing directions of a horizontal deflection coil and a coil current of a deflection yoke.

FIG. 4 is a plan view of a horizontal deflection coil of the deflection yoke.

FIG. 5 is a diagram illustrating a magnetic flux density of a magnetic field leaking vertically from an outer wall surface of a horizontal deflection coil.

FIG. 6 is a sectional view showing a configuration of a deflection yoke according to a second embodiment of the present invention.

FIG. 7 is a sectional view showing a configuration of a deflection yoke according to a third embodiment of the present invention.

[Explanation of symbols]

1. Deflection yoke, 2 (2R, 2L), 21 (21R, 21L)
... horizontal deflection coil, 2F, 2B ... crossover part of horizontal deflection coil, 2W ... window part of horizontal deflection coil, 3 ... separator, 4,41 ... vertical deflection coil, 5 ... magnetic core,
6 ... support part, 7 ... tightening band, 8,80 ... radiation mechanism,
9, 90 ... holding part.

 ──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Souichi Sakurai 292 Yoshida-cho, Totsuka-ku, Yokohama-shi, Kanagawa Prefecture Within the Multimedia Systems Development Division of Hitachi, Ltd. (72) Inventor Masao Ohara 1st Kitano, Makino, Majo, Mizusawa-shi, Iwate Media Electronics Co., Ltd.

Claims (5)

[Claims] 1. A deflection yoke having a horizontal deflection coil comprising a plurality of coils for generating a magnetic field for deflecting an electron beam in a horizontal direction and a vertical direction, and a deflection yoke having a vertical deflection coil. A deflection yoke characterized by having a heat dissipating mechanism that is held as such. 2. A deflection yoke having a horizontal deflection coil and a vertical deflection coil for generating a magnetic field for deflecting an electron beam in a horizontal direction and a vertical direction, wherein an absolute value of a magnetic flux density leaked from the horizontal deflection coil to an external space is different from that of the deflection yoke. A deflection yoke provided with a heat radiating mechanism which is held in contact with a coil of a smaller portion. 3. A deflection yoke having a horizontal deflection coil comprising a plurality of coils for generating a magnetic field for deflecting an electron beam in a horizontal direction and a vertical direction and a deflection yoke having a vertical deflection coil, wherein a holding portion made of a high resistivity material having a high thermal conductivity is provided. A deflection yoke provided with a heat radiation mechanism in contact with the horizontal deflection coil. 4. A deflection yoke having a horizontal deflection coil comprising a plurality of coils for generating a magnetic field for deflecting an electron beam in a horizontal direction and a vertical direction, and a vertical deflection coil.
A deflection yoke having a heat radiating mechanism in which a holding portion made of an inorganic insulator material having high thermal conductivity is brought into contact with the horizontal deflection coil. 5. A cathode ray tube display device comprising a cathode ray tube equipped with the deflection yoke according to claim 1.