JPS5838518Y2 - Focusing coil for image pickup tube - Google Patents

Description

[Detailed Description of the Invention] The present invention relates to a focusing coil for an image pickup tube, and the coil can be connected by overlapping the connecting wires of a plurality of coil parts in the space adjacent to each coil part in the winding direction of the coil. It is an object of the present invention to provide a focusing coil that eliminates connection lines orthogonal to the magnetic field, reduces local changes in the magnetic field, and can obtain a desired focused magnetic flux density distribution over the entire area.

In a video camera, in order to improve the image resolution, it is necessary to reduce the beam spot diameter on the scanning surface of the image pickup tube, and in order to obtain good resolution over the entire screen, it is necessary to Therefore, it is necessary to maintain this beam spot shape.

In order to reduce the diameter of the beam spot and maintain its shape, the focusing coil for the image pickup tube is made up of multiple coil parts each having a different winding distribution to generate a focusing magnetic field in the tube axis direction. The coils are configured as divided winding coils with different windings to obtain a desired focused magnetic flux density distribution.

FIGS. 1 and 2 show a perspective view and a winding connection diagram of an example of a conventional focusing coil for an image pickup tube, respectively.

In the figure, the first coil part 1 is made up of a bobbin that is sequentially laminated from the first layer (innermost layer) to the second layer (outermost layer) which is drawn out to the outside at the upper end in FIG. 1 as a lead wire 11. 2 in an aligned manner, and the first layer is drawn out as a connecting wire 1 at the lower end in FIG.

The second coil part 3 is connected to the first layer from the connection line 3□ of the first layer (innermost layer) connected to the connection line 1k of the first coil part 1 at point A.
The layers (outermost layer) are sequentially laminated and wound in an aligned manner around the bottle 4 fixed to the bobbin 2, and the first layer is drawn out as a lead wire 31 at the upper end of FIG.

However, this conventional focusing coil has a first coil part 1 and a second coil part 1.
Since the coil part 3 is connected only at one connection point A on the outside of the outermost layer of the coil, the lead wire 1
To pull out □, 3□ in the longitudinal direction of the coil, use lead wire 3.
1, the lead wire 31 must be drawn out orthogonally to the coil of the first coil portion 1, and the lead wire 31 protrudes outside the outermost layer of the coil.

Therefore, in this conventional focusing coil, magnetic flux is generated in a direction perpendicular to the magnetic flux generated in the coil parts 1 and 3 at the orthogonal part between the lead wire 3I and the coil, and the magnetic field is locally disturbed, resulting in a focused magnetic flux density. As a result, the distribution is locally disturbed and the shape of the beam spot is disturbed, causing local resolution degradation, which has a significant impact on the image quality of the reproduced image, especially in single-tube color imaging systems using frequency separation methods that require high resolution. There was a drawback of giving.

In addition, since the lead wire 3□ protrudes outside the outermost layer of the coil, when attaching a magnetic material such as permalloy as a magnetic circuit to the outer circumference of the coil, it is necessary to maintain a uniform distance from the outermost layer of the coil to the magnetic circuit. As a result, the magnetic resistance increases locally, and from this point as well, the focused magnetic flux density distribution is locally disturbed, the shape of the beam spot is disturbed, and the resolution is degraded.

Therefore, in order to prevent such local disturbances in the focused magnetic flux density distribution, there is a method of attaching a magnetic material such as permalloy to a part of the deflection yoke, but this method requires a large number of parts and can be constructed at low cost. Furthermore, since the above-mentioned disturbance of the magnetic field is not uniform for each focusing coil, a proper magnetic circuit is required for each deflection yoke, which has disadvantages such as poor productivity.

On the other hand, in the case shown in Fig. 1, the lead wire 3□ protrudes from the outermost layer of the coil, so a space exists between the focusing coil and the magnetic circuit, which allows the focusing coil and the magnetic circuit to come into close contact. This has disadvantages, such as a decrease in the conductivity of heat generated in the focusing coil and a risk of deteriorating the performance of the image pickup tube used.

The present invention eliminates the above-mentioned drawbacks, and one embodiment thereof will be described with reference to FIG. 3 and the following figures.

3 and 4 respectively show a perspective view and a winding connection diagram of an embodiment (series connection) of a focusing coil for an image pickup tube according to the present invention. In FIG. 3, the same components as in FIG. Assign the same number.

During assembly, in FIGS. 3 and 4, the first coil portion 5 is connected to the first layer (innermost layer) which is drawn out as a lead wire 5 □ at the upper end in FIG. 3 in the longitudinal direction of the coil. The layers are sequentially laminated up to the n-1th layer (one layer inside the outermost layer) and wound around the bobbin 2 in an aligned manner, and a connecting wire 5°-1 is drawn out to the outside at the lower end in FIG.

The second coil part 6 extends from the connection line 6□ of the first layer (innermost layer) connected to the connection line 5°-1 of the first coil part 5 at point B to the mth layer (outermost layer). The layers are sequentially stacked and wound around the bobbin 4 in an aligned manner, and the m-th layer is drawn out to the outside at the upper end in FIG. 3 as a connecting wire 6m.

Connect the connecting wire 5/ to the connecting wire 6m of the second coil portion 6 at the 0 point, and wind it around the nth layer (outermost layer) of the first coil portion 5,
At the upper end, a lead wire 6n is pulled out in the same direction as the lead wire 5.

The lead wires 50 and 6o are drawn out through cutouts 2a and 2b provided in the bobbin 2, respectively, and the connection wires 6° and 6m are drawn out through the cutouts 2c provided in the bobbin 2 and bobbin 4.
, 4a to the outside.

Note that the number of layers and wire diameter of the coil are selected to values that can obtain a desired magnetic flux density distribution.

At this time, the first coil part 5 connects the connecting wire 5°-1 of the layer one layer inside the outermost layer at its lower end with the connecting wire 6□ of the second coil part 6, and also connects the connecting wire 6 of the outermost layer 'o are connected to the connecting wires 6m of the second coil part 6, so a space having a thickness of one layer is formed in the adjacent part of the first coil part 5 and the second coil part 6, Connecting wire 5゜-0 and connecting wire 6□, connecting wire 6m and connecting wire 6'o are connected and fixed in the winding direction of the coil respectively in this space, and connection points B and C are housed in this space. .

In this way, the lead wires or connecting wires do not cross the coil at right angles as in the conventional coil shown in FIG. 1, so the desired focused magnetic flux density distribution can be obtained across the entire coil. Further, since the lead wire or the connecting wire does not protrude outside the outermost layer of the coil, the magnetic circuit can be attached closely to the outermost layer of the focusing coil, and a great heat dissipation effect can be obtained.

5 and 6 respectively show a perspective view and a winding connection diagram of another embodiment (parallel connection) of the focusing coil of the present invention.

During assembly, the first coil portion 7 is connected to the r-th layer from the first layer (innermost layer) drawn out at the upper end as the lead wire 7□.
Two layers (two layers less than the outermost layer) are sequentially laminated, and the connecting wire 7r-2 of the layer is drawn out at the upper end.

Connect the connecting wire 7'r-1 to the lead wire 7□ at point G and wind it around the r-1 layer outside the r-2 layer of the first coil part 7, and connect the connecting wire 7'r-1 of the layer. Pull it out at the bottom end,
The connection wire 8 of the second coil part 8 is connected to the connection wire 7r-1 at point E as the first layer (innermost layer), and is wound sequentially to the S layer (outermost layer), and the connection wire 85 is connected to the connection wire 85 at the upper end. Pull out.

Connect the connection line 8' of the first coil section 7 to the connection line 88 at point F.
, is connected and wound around the first layer (outermost layer) and drawn out as a lead wire 8r at the upper end, and a connecting wire 7r is connected at point D.
Connect to -2.

In this embodiment as well, a space with a thickness of one layer is formed at the lower end of the first coil part 7, so if the connecting wire is stored in this space, the winding perpendicular to the coil and the outermost There are also no protruding parts to the outside of the layer.

Other effects are the same as those of the embodiment shown in FIG. 3, so their explanation will be omitted.

Note that the number of divided coils in the above embodiment is two, the first coil part and the second coil part, but it is not limited to this. It may also be a split coil.

Further, in the present invention, the first coil portion and the second coil portion may use the same type of winding wire or may use different types of winding wires.

Furthermore, it is most desirable that the outermost layer be formed in an aligned manner like the other layers except for the space at the connection part, but it may also be wound with a certain space provided, as in so-called solenoid winding. effect can be obtained.

Note that this method has the advantage of increasing the degree of freedom in design when providing each coil.

As mentioned above, in the focusing coil for an image pickup tube according to the present invention, the outermost layer and the innermost layer of the winding of the coil section 1 are coated with one layer from the outermost layer of the other coil section adjacent to the coil section . For the winding of the inner layer, a space corresponding to the thickness of the winding of the soil layer is formed adjacent to the coil part of the - layer and the coil part of the iron base, and the winding of the winding is The outermost layer and the innermost layer of the coil section provided at the end of the other coil sections are connected to each other in the winding direction, and the outermost layer and innermost layer of the coil section are drawn out as external lead wires. The connecting wires and lead wires of the coil section and other coil sections are not perpendicular to the winding direction of the coil. Therefore, unlike conventional focusing coils, the magnetic field is not locally disturbed in the orthogonal sections, and the desired result is maintained. A focused magnetic flux density distribution can be obtained over the entire coil, which can improve the resolution of the reproduced image, and eliminates the need for special magnetic materials to correct the conventional focused magnetic flux density distribution. Because there are no parts, it can be constructed inexpensively and lightweight, and has good productivity.Furthermore, since the - coil part and other coil parts are connected in the space, there are no lead wires or connections. The wires do not protrude outside the outermost layer of the coil. Therefore, the magnetic circuit can be attached closely to the outermost layer of the coil, and a great heat dissipation effect can be obtained. It has the advantage of being able to be produced without variations in properties due to improved mechanical dimensional accuracy.

[Brief explanation of drawings]

1 and 2 are respectively a perspective view and a winding connection diagram of an example of a conventional focusing coil, and FIGS. 3 and 4 are a perspective view and a winding connection diagram of an example of a focusing coil of the present invention, respectively. 5 and 6 are a perspective view and a winding connection diagram of another embodiment of the focusing coil of the present invention, respectively. 2.2', 4...Bobbin, 5,7...
1st coil part, 6°8... 2nd coil part, 50
, 7□, 6n, 8r... Lead wire, 5, .
60,6'n, 6m, 7r-1,7'r-0,7r
-2, 8□, 8s, 8'r...Connection line, B-G
・・・・・・Connection point.

Claims (1)

[Scope of utility model registration request] In a focusing coil for an image pickup tube in which a plurality of coil portions each having a laminated winding are connected and fixed in the longitudinal direction, the outermost layer of the coil portion and the innermost layer of the coil portion among the plurality of coil portions are used. The windings include the outermost layer winding of another coil portion adjacent to the − coil portion and the winding layer one layer inside the outermost layer, and the − coil portion and the iron base coil portion. A space corresponding to the thickness of the one layer of winding wire is formed adjacent to the wire, and the wires are overlapped and connected in the winding direction of the wire in the space, and the upper end in the longitudinal direction of the coil portion of the iron base is connected. A focusing coil for an image pickup tube having a structure in which the outermost layer winding and the innermost layer winding of a coil section provided in the section are drawn out as lead wires for connecting to an external circuit.