JPH07176434A - Horizontal output device - Google Patents

Abstract

PURPOSE:To prevent electric field radiation from a display by effectively filtering out the electric field component from the deflecting coil of the deflecting yoke of a horizontal output device. CONSTITUTION:On a film body 19 facing a horizontal deflecting coil 18 of a deflecting yoke 5, a Faraday shield body 17 which is formed into a pattern of comb-like stripe with a non-magnetic conductor 20 is wound on the neck side of a cathode ray tube 8 so that it is bonded and fixed, with one end side 22 of the conductor 20 connected to a ground. On the outside of the Faraday shield body 17, deflecting yoke 5 is attached, thus a horizontal output device is configured. Since the conductor 20 of Faraday shield body 17 is formed just inside the horizontal deflecting coil 18 which is an origin of electric field radiation, electric field component is effectively shielded near the source of release by the conductor 20. Since the conductor 20 is non-magnetic, it does not interfere with the deflecting magnetic field generated by the deflecting coil 18, and, since the conductor 20 is stripe-shaped, no eddy current take place in the conductor 20 even if deflecting magnetic field passes through, accompanied with no electric power loss, nor, internal deflecting magnetic field disturbance.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a horizontal output device used in a television receiver or a display device.

[0002]

2. Description of the Related Art Recently, there has been a concern that an electric field component may leak from the screen of a television receiver or a display device to have an adverse effect on the human body. This leakage electric field is caused by the following items.

Beam scanning by deflection driving of a television receiver or the like is performed by a circuit of a horizontal output device as shown in FIG. In the figure, a flyback pulse 7 generated on the primary coil side of the flyback transformer 1 is applied to the deflection yoke 5 and the flyback transformer 1. The flyback pulse applied to the flyback transformer 1 is boosted by the flyback transformer 1 and applied to the anode (not shown) of the cathode ray tube 8.
On the other hand, the horizontal output transistor 4 and the damper diode 2
The sawtooth wave current is applied to the horizontal deflection coil of the deflection yoke 5 by the switching operation of 1 to scan the beam. By such circuit operation, a voltage component having the flyback pulse 7 as a voltage source is generated from the horizontal deflection coil of the deflection yoke 5.

FIG. 3 shows the layout of the horizontal output device together with the cathode ray tube 8. As shown in the figure, the flyback transformer 1 is located at a rear corner of the housing 23, and a metal plate such as a chassis (not shown) and a heat sink (not shown) is located at the rear corner. Therefore, the electric field component generated from the flyback transformer 1 is shielded by this metal plate and does not leak to the outside. Also,
Since the flyback transformer 1 is located away from the screen 12, the influence on the electric field leaking forward of the screen 12 is small. On the other hand, it can be said that the electric field component generated from the horizontal deflection coil of the deflection yoke 5 has a great influence on the electric field leaking forward of the screen 12 for the following reason. That is,
When the metal frame body (anode electrode or the like) 10 connected to the shadow mask 9 in the cathode ray tube 8 and the horizontal deflection coil of the deflection yoke 5 function as a capacitor, and the flyback pulse 7 of the AC voltage is applied to the horizontal deflection coil. , Metal frame 10
The AC component is also induced, and the induced voltage of the metal frame 10 is applied to the shadow mask 9, and the shadow mask 9 causes the screen
12 An electric field will be emitted forward.

In order to prevent the adverse effect on the human body due to the electric field emission from the screen, the following measures have been conventionally taken. The first one blocks the electric field emission from the screen 12 by mounting a filter on the screen 12. This filter is formed by arranging a conductive material in a mesh on a transmission plate covering the screen 12, or the transmission plate itself is formed of a conductive material, and one end side of these conductive materials is connected to the ground. By doing so, the conductive material portion functions as a metal shield, and blocks the electric field emission toward the front of the screen 12.

The second measure is that in the circuit shown in FIG.
The electric field component generated from the horizontal deflection coil is dropped to the ground side via the resistor 15 and the smoothing capacitor 16.

[0007]

However, according to the first measure, the wiring work for connecting one end side of the conductive material portion of the filter to the ground side is troublesome, and the filter has a deflection yoke which is an electric field generation source. Since it is located away from the horizontal deflection coil of No. 5, there is a drawback that the electric field component cannot be removed efficiently.

Further, in the case of the second countermeasure, the resistance value of the resistor 15 is large because the resistor 15 originally protects the smoothing capacitor 16, and the smoothing capacitor 16 itself also has an internal resistance. Therefore, the electric field component generated from the horizontal deflection coil could not be completely dropped to the ground.
In addition, the resistor 15 should be used to completely drop the electric field component to ground.
However, if so, there is a problem that the smoothing capacitor 16 cannot be protected, and the capacitor 16 is destroyed when high-voltage discharge from the cathode ray tube 8 side occurs.

The present invention has been made in order to solve the above-mentioned conventional problems, and the purpose thereof is to more effectively remove the electric field component induced in the shadow mask 9 from the horizontal deflection coil of the deflection yoke 5 and to make the screen 12 An object of the present invention is to provide a horizontal output device in which electric field leakage from the inside is prevented.

[0010]

In order to achieve the above object, the present invention is constructed as follows. That is, according to the present invention, in a horizontal output device in which a deflection yoke is attached to a cathode ray tube, a Faraday structure in which a non-magnetic conductor is formed in a stripe shape so as to face a deflection coil of the deflection yoke that is a generation source of field emission. A shield body is arranged and the Faraday shield body is connected to the ground.

[0011]

The electric field component originating from the deflection coil of the deflection yoke is effectively shielded by the conductor portion of the Faraday shield arranged so as to face the deflection coil. The ingredients can be reduced. Also,
Since the conductor of the Faraday shield is a non-magnetic material,
It does not interfere with the deflection field created by the deflection coil. Further, even if the deflecting magnetic field passes through the conductor, since the conductor is formed in a stripe shape, the eddy current is prevented from being generated in the conductor.

[0012]

Embodiments of the present invention will be described below with reference to the drawings. In the description of the present embodiment, parts having the same names as those in the conventional example are designated by the same reference numerals, and duplicate description thereof will be omitted. FIG. 1 shows an embodiment of a horizontal output device according to the present invention. A characteristic of this embodiment different from the conventional example is that a Faraday shield 17 is mounted between the neck side of the cathode ray tube 8 and the deflection yoke 5, as shown in FIG.

In this Faraday shield body 17, a conductor 20 is formed on a film body 19 facing the horizontal deflection coil 18 by utilizing a fan-shaped film body 19 as shown in FIG. . This conductor 20 is formed with a plurality of stripes 20a extending straight from the head side to the neck side, and one end side of each stripe 20a is connected to form a comb-shaped stripe shape. This Faraday shield body
17 is wound along the neck side of the cathode ray tube 8 as shown in (c) of the figure, and is attached to the cathode ray tube 8 with an adhesive or the like, and one end side 22 of the conductor 20 is connected to the ground. There is. The deflection yoke 5 is mounted so as to cover the outer periphery of the Faraday shield body 17 to form a horizontal output device.

This embodiment is constructed as described above,
Since the conductor 20 of the Faraday shield body 17 is formed at a position facing the horizontal deflection coil 18 of the deflection yoke 5, the conductor 20 of the Faraday shield body 17 and the horizontal deflection coil 18 function as a capacitor, and the horizontal deflection coil 18 The electric field component generated from is induced in the conductor 20 and dropped to the ground connected to the conductor 20. Therefore, the electric field component is not induced from the horizontal deflection coil 18 to the shadow mask 9, and the electric field is not emitted from the shadow mask 9.

On the other hand, the conductor 20 of the Faraday shield body 17
Is a non-magnetic substance, the deflection magnetic field generated by the horizontal deflection coil 18 is not disturbed by the conductor 20,
Further, since the conductor 20 of the Faraday shield body 17 is formed in a thin comb-shaped stripe shape, even when the deflection magnetic field passes through the conductor 20, no eddy current is generated. Moreover, the internal deflection magnetic field is not disturbed.

Therefore, according to the present embodiment, the electric field generated from the horizontal deflection coil 18 is effectively and completely shielded by the conductor 20 of the Faraday shield body 17 arranged facing the horizontal deflection coil 18. Therefore, it is possible to prevent adverse effects on the human body due to field emission.

Further, since the deflection magnetic field produced by the horizontal deflection coil 18 is not disturbed by the Faraday shield body 17, the function of the horizontal deflection coil 18 is not impaired.
Furthermore, since no eddy current is generated in the Faraday shield body 17 due to this deflection magnetic field, no power loss due to eddy current occurs. Moreover, the internal deflection magnetic field is not disturbed.

Further, the conductor of the Faraday shield body 17
The Faraday shield body 17 is arranged because the 20 is arranged so as to face the horizontal deflection coil 18 of the deflection yoke 5 which is the source of the field emission.
The conductor 20 has a minimum area such that it is arranged to face the horizontal deflection coil 18, and can exert the maximum effect of shielding the field emission from the source.

Further, according to the present embodiment, since the electric field leakage preventing means is provided at the manufacturing stage in which the deflection yoke is incorporated in the cathode ray tube 8, the filter is attached to the screen 12 or the filter is mounted as in the conventional case. There is no need for troublesome work such as connecting the to the ground.

The present invention is not limited to the above-mentioned embodiment, and various embodiments can be adopted. For example, in the above embodiment, the Faraday shield body 17 uses the fan-shaped film body 19, but a rectangular film body 19a may be used as shown in FIG. 2A, and the shape of the film body does not matter. . Also, the Faraday shield body 17 is the film body 1
Instead of using 9, 19a, a bobbin 19b made of resin or the like may be used as shown in FIG. 2 (b).

Further, in the above embodiment, the conductor 20 of the Faraday shield body 17 was patterned in a comb-shaped stripe pattern at a position opposed to the horizontal deflection coil 18 of the deflection yoke 5, but FIGS. As shown in, the conductor 20 may be patterned in a comb-shaped stripe pattern over the entire surface of the Faraday shield body 17. Further, in the above embodiment, the conductor 20 is striped in the direction extending from the neck side to the head side.
20a was formed, but as shown in FIG. 2 (b), stripes were formed in a direction perpendicular to the direction extending from the neck side to the head side.
20b may be formed, or stripes may be formed in other directions.

Further, in each of the above-mentioned embodiments, the conductor 20 is formed in a comb-like stripe shape which connects one end sides of the plurality of stripes 20a and 20b, as shown in FIGS. 2 (c) and 2 (d). Thus, both ends of each of the plurality of stripes 20a and 20b may be connected.

Further, in the above-described embodiment, the stripe 20a of the conductor 20 is formed in the Faraday shield body 17 in a straight line shape. However, the thin wave shape as shown in FIG. It may be formed into a thin sawtooth shape as shown, or may have another shape.

Further, in the above embodiment, the Faraday shield body 17 is attached to the neck side of the cathode ray tube 8 with an adhesive or the like, but the Faraday shield body 17 is attached to the horizontal deflection coil 18 side of the deflection yoke 5 with an adhesive or the like. May be. Further, the Faraday shield body 17 may not be attached to the cathode ray tube 8 or the deflection yoke 5, but may be simply fitted and disposed between the cathode ray tube 8 and the deflection yoke 5. In this case, the Faraday shield body
Conductors 20 are formed in stripes over the entire surface of the Faraday shield 17 as shown in FIGS. 2 (a) to 2 (f) so that 17 may move around the outer circumference of the cathode ray tube 8. Alternatively, a positioning means may be provided so that the Faraday shield body 17 does not move, and the stripe-shaped conductor 20 may be formed only at a position facing the horizontal deflection coil 18.

[0025]

According to the present invention, since the conductor of the Faraday shield is formed at a position facing the deflection coil of the deflection yoke which is the source of the field emission, the electric field is completely shielded from the source by the Faraday shield. To be done. In this way, the conductor of the Faraday shield exhibits the maximum effect of completely shielding the electric field with a minimum area that is arranged to face the deflection coil, and is very efficient. With this conductor, the electric field is shielded more completely than before, so that the adverse effect on the human body due to field emission can be prevented.

Since the conductor of the Faraday shield is a non-magnetic substance, the deflection magnetic field generated by the deflection coil of the deflection yoke is not disturbed by this conductor. Furthermore, since the conductors are formed in stripes, no eddy current is generated in the conductors even if the deflection magnetic field created by the deflection coil passes through this conductor portion, and there is no power loss due to eddy currents. It does not disturb the deflection magnetic field.

Furthermore, since a means for preventing electric field leakage is provided at the manufacturing stage in which the deflection yoke is incorporated in the cathode ray tube, it is troublesome to mount a filter on the screen and connect the filter to the ground as in the conventional case. Does not need

[Brief description of drawings]

FIG. 1 is an explanatory diagram showing an embodiment of a horizontal output device according to the present invention.

FIG. 2 is an explanatory view showing another embodiment of the Faraday shield body that constitutes the horizontal output device according to the present invention.

FIG. 3 is a schematic diagram showing an arrangement of a horizontal output device and a cathode ray tube.

FIG. 4 is a circuit configuration diagram of a horizontal output device.

[Explanation of symbols]

 5 Deflection yoke 8 Cathode ray tube 17 Faraday shield 18 Horizontal deflection coil (deflection coil) 20 Conductors 20a, 20b Stripe

Claims (1)

[Claims] 1. A Faraday shield in which a non-magnetic conductor is formed in a stripe shape in a horizontal output device in which a deflection yoke is mounted on a cathode ray tube so as to face a deflection coil of the deflection yoke which is a source of field emission. A horizontal output device in which the body is placed and this Faraday shield body is connected to the ground.