JPS5812358Y2 - Satsuzou Kanyou Henko York - Google Patents

Description

[Detailed explanation of the idea] The present invention relates to a deflection yoke for an image pickup tube.

In the conventional deflection yoke of this type, a shield layer 2 is provided on the surface of the inner bobbin 10 as shown in FIG.
A vertical/horizontal deflection coil 3 is attached to the bobbin 5, and a bobbin 5 on which a focusing coil 4 is wound is housed, and a permalloy shield case 6 is provided.

Therefore, since two 1.5 bobbins are required, the shape is relatively large and the weight is heavy.

The present invention has been devised to deal with such problems, and will be explained below based on drawings showing embodiments.

First, in FIG. 1 showing the first embodiment, reference numeral 11 denotes a focus coil that is wound and fixed using an adhesive wire. and the focus coil 11
An insulating tape 14 is wrapped over the top of the insulating tape 14, and vertical and horizontal deflection coils 15 are attached from above, and both ends of the permalloy shield case 16 are fixed to the fixing plate 12, 13 for secure integration.

In addition, 17 in the figure is a target contact part, and an image pickup tube [not shown]
It acts to extract the video signal by contacting the target electrode.

18 is an alignment magnet, and 19 is a fixing band.

By the way, as shown in Fig. 2, the front and rear both side fixing plates 12 and 13
Step portions 12b and 13b are provided in the step portions 12b and 13b.
It is also possible to engage and attach the focus coil 11 to.

Next, the effects of the present invention will be explained in detail by comparing FIG. 1 and FIG. 3.

Conventionally, the thickness of Bohin is 1 y+o+r-1,5w
In FIG. 3, the inner bobbin 1 needs to have a wall thickness of 1.5 mm, especially in order to prevent winding.

Therefore, the wall thickness of inner bobbin 1 is 1.5.
Assuming that the wall thickness of is 1.0WrrrL, the first
In the case shown in the figure, the outer diameter size can be made smaller by a diameter of 5 Wrrn than that in FIG.

In addition, the strength of the magnetic field due to the focus coil is expressed as: Bz: strength of the magnetic field on the central axis μ: magnetic permeability; N: number of turns; ■: current; radius of the near coil; t: length of the focus coil; If the number of turns is smaller, the number of turns can be reduced accordingly, and together with the size of the bobbin, the size can be significantly reduced.

That is, by using a fixed-wound loose coil 11 to create a bobbinless structure as shown in FIG. 1, it is possible to reduce the external dimensions by more than the thickness of the bobbin that is no longer in use.

Further, by providing the focus coil inside the deflection coil, the electric wire can be shortened and the weight can be reduced.

Furthermore, when the focus coil is located outside as in the conventional case, harmonics of the sawtooth current supplied to the deflection coil 3 are mixed into the video signal via the target contact portion 17, as shown in FIG. However, according to the present invention, the shielding effect can be obtained by grounding the inner focusing coil in an alternating current manner. Since it is sufficient to provide the shield layer 20 only in portion A, the configuration can be simplified.

FIG. 4 shows a structure in which a shield layer 20 is provided.

In the above embodiment, the focus coil is constructed by winding an adhesive wire, but it may also be constructed by winding a polyurethane wire or the like and fixing it with an adhesive.

As described above, according to the present invention, the front and rear fixing plates are attached to both ends of the focus coil with fixed windings, and the deflection coil is provided in the upper layer of the focus coil, so that the inner bobbin 1 and To simplify the electrostatic shielding of a deflection coil by eliminating the need for a bobbin 5, and by grounding the cass coil in an alternating current manner, thereby contributing to the reduction in weight and size of a deflection yoke for an image pickup tube by simplifying the structure. It is something that can be done.

[Brief explanation of drawings]

Fig. 1 is a vertical sectional view showing a first embodiment of the present invention, Fig. 2 is a longitudinal sectional view of main parts showing a second embodiment of the invention, Fig. 3 is a longitudinal sectional view showing a conventional example, and Fig. 4 is a longitudinal sectional view showing a conventional example. The figure is an explanatory diagram of the first embodiment. 11... Focus coil, 12...
Front fixing plate, 13... Rear fixing plate, 12a, 1
3a...groove, 14...-insulating tape, 1
5... Deflection coil, 16... Permalloy shield case, 12b, 13b... Step portion.

Claims (1)

[Scope of utility model registration request] 1. A deflection yoke for an image pickup tube, characterized in that a screw coil configured with a fixed winding is fixedly attached to both front and rear fixing plates at both ends of the deflection coil inside the deflection coil.