JPS594436Y2 - Image tube deflection device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an image pickup tube deflection device that is installed in an image pickup tube and generates a deflection magnetic field for scanning an electron beam.

Generally, an image pickup tube requires a deflection magnetic field to scan an electron beam.

For this reason, in a typical image pickup tube, an image pickup tube deflection device, which is formed from a deflection coil, a bobbin, etc., is attached to the outer periphery of the image pickup tube, and a deflection magnetic field is obtained by passing a predetermined deflection current through this deflection coil.

FIG. 1 is a diagram showing a conventional image pickup tube deflection device. The deflection device 1 is composed of a hollow cylindrical bobbin 2 made of insulating synthetic resin, and a deflection coil 3 wound around the bobbin 2. has been done.

The deflection device 1 then inserts the image pickup tube 4 into the hollow part of the bobbin 2 and adjusts it to the optimum position, and then tightens the tightening portion 2a formed on the bobbin 2 with the tightening band 5, so that the outer circumferential surface of the image pickup tube Fixed.

The deflection device fixed to the image pickup tube is attached to the chassis 6 directly or via a mounting member as shown in the figure,
As a result, the image pickup tube 4 is accurately fixed at a position required by the optical system mechanism including the lens 11 and the like.

However, since the conventional image pickup tube deflection device 1 has a structure in which the stem portion 4a of the image pickup tube 4 is tightened and fixed, it has the following drawbacks.

In other words, ABS resin is usually used as a material for the bobbin around which the deflection coil is wound because it is easy to mold and has good electrical characteristics, but it has a relatively low coefficient of thermal expansion α. The disadvantage is that it is large.

For this reason, the bobbin deforms due to the temperature increase, and as a result,
An error occurs in the relative positional relationship between the image pickup tube and the optical mechanism,
Face play of the image pickup tube 4) A phenomenon occurs in which the optical image appearing on the image pickup tube 4b becomes out of focus.

For example, the thermal expansion coefficient α of ABS resin is 7.0×10-5
mm/°C, and the bobbin 2 in the image pickup tube deflection device
The distance l between the chassis mounting part 2b and the tightening part 2a is approximately 10
Assuming that it is 0 mm, a temperature rise of about 50°C will result in a temperature increase of about 0.
3-Q, positional deviation of about 4 mm occurs.

In this type of image pickup tube deflection device, a positional deviation of about 0.1 mm affects the optical image blurring on the face plate, so the problem of positional deviation due to temperature rise in conventional devices cannot be ignored.

Furthermore, considering the fact that the stem of the image pickup tube has a built-in heater for thermionic emission and the operating conditions of the image pickup tube device, it is quite possible that the temperature will rise by about 50°C. be.

The present invention has been devised to solve the above-mentioned drawbacks of the conventional image pickup tube deflection device, and will be described in detail below with reference to embodiments shown in the drawings.

FIG. 2 is a diagram showing an image pickup tube deflection device 9 embodying the present invention.

In the figure, reference numeral 7 denotes a hollow cylindrical bobbin around which the deflection coil 3 is wound, and an imaging tube 4 is inserted into the hollow portion of the bobbin, similar to conventional bobbins.

The bobbin 7 in the deflection device of the present invention has an end on the chassis attachment side extending along the outer periphery of the imaging tube 4, and a tightening portion 7a is formed at the target ring 4C of the imaging tube 4. This is different from the conventional bobbin 2.

In the image pickup tube deflection device of the present invention, the above-mentioned tightening portion is tightened by a tightening band 8.
It is characterized by being tightened and fixed with, etc.

The tightening portion 7a may have any structure as long as it contracts uniformly in the circumferential direction and presses against the periphery of the target ring by tightening the tightening band.

For example, it is conceivable to have a structure in which a pressing tongue is formed by a cut groove, similar to the conventional tightening part.

The structure for attaching the image pickup tube device to the chassis may be one in which the attachment portion 7b is integrally molded on the bobbin as in the conventional case, or it may be attached via other attachment means.

When the mounting portion 7b is integrally molded, it is convenient to form the protrusion 7C to prevent the tightening band from falling off at the same time, thereby preventing the tightening band from falling off.

Furthermore, if a position regulating protrusion 7d is formed inside the tightening portion 7a to engage with the target ring to regulate the position, stronger and more stable tightening can be achieved.

As shown in FIG.
If the structure is such that when the tightening band 10 is tightened, the target ring 4C is pressed against the side surface of the target ring 4C together with the target ring accommodating jaws 7e of the bobbin 7, an even stronger fixation can be achieved.

In this case, a cut groove or an insertion hole is formed in a portion of the tightening portion corresponding to the tube clamp portion 10a.

Since the image pickup tube deflection device of the present invention is as described above,
The following beneficial effects can be obtained.

That is, since the distance between the chassis mounting part and the tightening part is extremely short compared to conventional devices, the problem of optical image blur due to temperature changes is solved.

For example, even if it is assumed that there is a temperature rise of approximately 50°C, if the distance is approximately 25mm or less, the positional deviation will be reduced to 0.1m.
It is possible to keep it within m.

In addition, since the target ring part is tightened rather than the flat glass part with a small coefficient of friction as in the past, strong and stable tightening is achieved, and the structure has excellent axial holding force and is able to withstand shocks. Strong against

Therefore, the image pickup tube deflection device of the present invention can prevent optical image blurring caused by temperature rise, and can be installed much more strongly and stably than in the past.

[Brief explanation of the drawing]

Fig. 1 is a sectional view showing a conventional image pickup tube deflection device, Fig. 2 is a sectional view showing an example of an image pickup tube deflection device implementing the present invention, and Fig. 3 is a sectional view showing an example of an image pickup tube deflection device implementing the present invention. FIG. 7 is a cross-sectional view showing another example of the device. In the figure, 2 and 7 are bobbins, 2 a and 7 a are tightening parts, and 3
indicates a deflection coil.

Claims (2)

[Scope of utility model registration request] (1) The deflection coil is separated from the bobbin on which the deflection coil is wound, and the bobbin is made into a hollow cylindrical shape so that the imaging tube can be inserted into it, and the imaging tube is inserted and placed in a predetermined position. In this case, a tightening part is formed at a position corresponding to the target ring of the image pickup tube, a chassis mounting part is provided on the bobbin in proximity to the tightening part, and the tightening part is tightened by a tightening means. An image pickup tube deflection device, characterized in that the image pickup tube is fixed near the mounting portion. (2) A tube clamp portion protruding inside the tightening portion is formed on the tightening means, and a target ring housing jaw portion is formed on the tightening portion, so that when the tightening means is tightened, the tube clamp portion The image pickup tube deflection device according to claim 1, wherein the side surface of the target ring is pressed and held between the target ring housing jaw portion and the target ring housing jaw portion.