JPH0145269Y2 - - Google Patents

Description

[Detailed Description of the Invention] The present invention relates to a high voltage generator that combines a flyback transformer and a high voltage variable resistor. Figure 1 shows a circuit configuration diagram of a high voltage generator, and 4 indicates a primary coil 1, a secondary coil 2, and a core 3.
5 is a multi-voltage rectifier circuit for voltage-doubling rectification of the high-voltage pulse generated in the secondary coil 2, and the multi-voltage rectifier circuit 5 includes rectifier diodes D ₁ , D ₂ , _D3 and voltage doubler capacitors _C1 , _C2 . 6 is a high-voltage variable resistor for obtaining a medium-high voltage by dividing the rectified and smoothed voltage obtained from the middle of the multi-voltage rectifier circuit 5,
The voltage adjusted by sliders 7 and 8 sliding on the focus resistor Rf and the screen resistor Rs printed and fired as a thick film on the substrate of the high voltage variable resistor 6 is applied to the focus of the cathode ray tube. It is extracted as voltage and screen voltage. By the way, recently, many high voltage generators have been manufactured in which the high voltage variable resistor 6 and the flyback transformer 4 are integrated. FIG. 2 shows a conventional example of a flyback transformer coil storage case used in this type of high voltage generator, and FIG. 3 shows a multi-voltage rectifier circuit 5 inside the case 9.
The case 9 is shown housing a coil bobbin 10 wound with the high-voltage coil 2 and low-voltage coil 1 of the flyback transformer 4, and a high-voltage variable resistor 6 is attached to one side of the case 9.
It is completed by injecting insulating resin into the inside and hardening it. However, when a flyback transformer and a high voltage variable resistor are integrated in a conventional structure,
The heat generated in the high-voltage variable resistor is transmitted through the resin and has an adverse effect on the coil of the flyback transformer and the diodes of the multi-voltage rectifier circuit connected to it, impairing its reliability as a high-voltage generator. It was hot. Therefore, in order to improve the heat dissipation performance of the high voltage generator, it has been considered to provide a space between the flyback transformer and the high voltage variable resistor to form a cavity for heat dissipation. In addition to increasing this heat dissipation, this space also has the following functions:
It also has the function of protecting the substrate of the high voltage variable resistor 6 by reducing the stress generated when the injected resin hardens (see Utility Model Publication No. 63-6929, H04N3/19). By the way, when molding a high-voltage variable resistor with resin, it is necessary to make the grooves large in order to smoothly pour the resin, resulting in an increase in size. The present invention has been devised to eliminate the above-mentioned drawbacks. The following description will be made with reference to FIGS. 4 to 7, but the same components as those of the prior art will be designated by the same reference numerals and the description thereof will be omitted. FIG. 4 shows a flyback transformer coil storage case 11 used in the high pressure generator of the present invention. On one side of the case 11, a space 14 formed by a double wall 13 is continuous in the air, leaving a notch 12. The high voltage and low voltage coils 2 and 1 are housed within this case 11. And this high voltage, low voltage coil 2,
As shown in FIG. 6, the core 3 is installed in the case 11 on the side 11a where the core 3 is installed, and the housing 20 is provided on the side 11b opposite to the side 11a where the core 3 is installed. The long notch 12 is provided at a position continuous to the storage part 20 free of obstacles. Therefore, the resin smoothly flows into the high voltage variable resistor 6 side via the long notch 12. In the present invention, in order to downsize the high voltage generator, parts (printed circuit board, capacitor _C1, etc.) constituting at least a part of the multiplier rectifier circuit 5 are installed in the storage section 20 as shown in FIG. We are promoting the miniaturization of high-pressure generators. To assemble such a high voltage generator, as shown in FIG. The case 11 is attached by fitting the concave portion 15 provided thereon with the convex portion 16 provided on the case 11. After that, an insulating resin 17 such as epoxy resin is injected into the case 11 as shown in FIG . The high voltage variable resistor 6 is mostly separated from the coil of the flyback transformer by a space 14 formed by the double wall 13. Therefore, most of the heat generated in the high-voltage variable resistor 6 is radiated into the space 14 formed by the double wall 13, so that the high-voltage coil 2, low-voltage coil 1, and multiple voltage coil of the flyback transformer are radiated. Rectifier circuit 5
diodes D ₁ , D ₂ , and D ₃ are not adversely affected. FIG. 7 shows the high pressure generator of the present invention in the long notch 12.
The case 11 is shown in cross section, and the lead wire l that supplies the medium-high voltage obtained from the multi-voltage rectifier circuit 5 to the high voltage variable resistor 4 is connected to the long notch 12.
It is designed to be inserted through the inside. The table below shows experimental data comparing the temperature effects of heat on the high-voltage variable resistor in the conventional example and the present invention. [Table] The above experiment was measured using a thermocouple, and the ambient temperature was 60℃, the primary (low-voltage coil) side voltage of the flyback transformer [KVp-p], the primary current 600 [mA],
High voltage output voltage 26 [KV], beam current 1.32 [mA],
The experiment was conducted under the conditions that the resistance value of the high-voltage variable resistor was 60 [MΩ] and the current value flowing through it was 220 [μA]. As described above, in the present invention, the space 14,
In a high-pressure generator including the long notch 12 connected to the housing section 20, a part of the rectifier circuit 5 is disposed in the housing section 20, so that the high-pressure generator can be miniaturized.

[Brief explanation of the drawing]

Figure 1 is a circuit configuration diagram of a high voltage generator, Figure 2 is a perspective view of a case used in a conventional high voltage generator, and Figure 3 is a perspective view showing a flyback transformer and a high voltage variable resistor attached to it. , Fig. 4 is a perspective view of a case used in the high voltage generator of the present invention, Fig. 5 is a perspective view showing the case with a flyback transformer and a high voltage variable resistor attached to it, and Fig. 6 is a perspective view of the case with an insulating resin applied thereto. FIG. 7 is a plan view showing the state in which the present invention is applied, and a sectional view of the main parts of the high pressure generator of the present invention. 6 ...High voltage variable resistor, 11...Flyback transformer coil storage case, 13...Double wall, 1
4...A space formed by double walls.

Claims (1)

[Claims for Utility Model Registration] A high-voltage variable resistor 6 attached to the side surface of a case 11 for storing a flyback transformer, and an epoxy resin 1 injected into the case 11.
7, the high-voltage coil and low-voltage coils 2 and 1 of the flyback transformer 4, which are housed biased toward the core side 11a to which the core 3 of the flyback transformer 4 is attached among the side surfaces of the case 11; and the high-voltage coil and the low-voltage coil a space 14 formed by a double wall between the coils 2, 1 and the high voltage variable resistor 6 and into which the epoxy resin 17 is not injected; and a storage section 20 provided on the opposite side 11b from the core side 11a; A long notch 12 for resin inflow is provided at a position continuous with the storage portion 20 and adjacent to the space 14 in order to mold a part of the high voltage variable resistor 6 with the epoxy resin 17; and the flyback. A high voltage generator comprising: a rectifier circuit 5 for rectifying a signal from a transformer ₄ ; Generator.