JPH06503448A - High voltage transformer for television receivers - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

[Detailed description of the invention] High voltage transformer for television receivers The invention starts from a high-voltage transformer according to the preamble of claim 1. this shape A transformer of the type is known from West German Patent Application No. 3514308. Ru. This type of transformer is suitable for television receivers on the order of 25kV. Generates high pressure.

having a relatively large cathode ray tube, e.g. 16:9 aspect ratio or 85c In a television receiver with a screen diagonal of m, the ratio is on the order of 35 kV. Relatively high pressure is required. The power loss of the transformer for this type of high voltage is high temperatures can be avoided, which increases heat generation and is necessary for heat dissipation. geometric dimensions increase.

The problem of the present invention is to solve the problem of the power loss generated in the transformer in this type of high voltage transformer. It is to reduce the force. This problem is solved by the invention as set forth in claim 1. It will be done. Advantageous embodiments of the invention are set out in the further claims.

The present invention first focuses on analyzing the types of losses that occur in this type of transformer as a whole. Based on. The first type of loss is the area formed by the hysteresis curve. This is due to ferrite loss due to reversed magnetization of the core corresponding to . This type of loss It can only be reduced by improving the quality of light materials. second type The loss is due to wire resistance and copper loss due to skin effect. No. 3: The loss of class m is 1. Suppress losses in high-voltage rectifier diodes, which include forward voltage, conduction current, and blockage. Stopping voltage, blocking current, and switches and switches when switching from blocking state to conducting state This is caused by switch losses when switching over and vice versa. Fourth type of loss is the dielectric loss due to displacement current in the dielectric material, which is generally formed by injection resin. be. The first three types of losses are particularly important for technical reasons and due to the available components. Therefore, there is a lower limit. Therefore, the present invention focuses on the fourth type of loss. that time The present invention is based on the following considerations. Dielectric loss is particularly important in the primary and secondary windings or Occurs in the area between the high voltage windings. This is because the maximum voltage difference occurs here. This is because that. Therefore, this region should be formed so that as little as possible electric field is generated. If this is possible, dielectric loss can be significantly reduced. In the present invention, this means that 1 Achieved only by a particularly advantageous distribution of the pulsed voltage to the secondary and secondary windings be done. Moreover, it is The pulses are made to have approximately the same amplitude and the same polarity. In that case, actually two Since the difference in pulse voltage across the windings disappears, the desired field-free air is created. 2, and losses due to dielectric displacement currents are largely avoided. The important advantages are: The field-free space is not created by additional means, but in any case by This can be achieved simply by cleverly arranging the materials. in the dielectric surrounding the windings. The reduction of the dielectric displacement current in the It will be done. This eliminates the natural oscillations that would otherwise be caused by displacement currents. movement is reduced. This reduction in harmonics improves the internal resistance and thus the This will reduce the noise generated during the process. The material surrounding the winding as a whole The load on the injection resin is also advantageously reduced.

Next, the present invention will be explained using the drawings.

FIG. 1 is a schematic diagram showing the structure of the high voltage transformer of the present invention, FIG. 2 is an equivalent circuit diagram of the transformer shown in FIG. 1.

In the following description, only pulsed voltages acting on the transformer will be considered. its development ・Does not consider the generated DC voltage. The reason is that this DC voltage has a dielectric displacement current, This is because no power loss is generated.

In FIG. 1, a coil bobbin 7 supporting a primary winding 3 is supported on the core 1. It is. The primary winding 3 consists of six layers. The winding end consisting of the lower layer is , is connected at terminal B to an operating voltage of 10B. The winding ends consisting of the upper layer are , are connected to the switching transistor 13 at terminal d. This switch The switching transistor is activated by a line frequency switching voltage Z at terminal C. controlled. The pulse voltage at the terminal is zero. Pulse voltage at terminal d has a flybank voltage value of +1200V. Therefore, the pulse voltage It increases continuously with each turn from the zero value at the terminal to the maximum value at the terminal.

That is, the pulse voltage drops by about 16% over the axial length of the upper layer of winding 3 and The pulse voltage at the right edge of the top layer is +100OV. Therefore, the pulse voltage is substantially constant over the axial length of the coil bobbin 7 in the layer above the wire 3 and 11 It has an average value of 00v.

Above the coil bobbin 7 with the primary winding 3 are formed by walls 8, 16 in total. A coil bobbin 2 having chambers Ka to Kp is arranged. these The chamber is filled with partial windings 4a to 4p of the secondary winding or high voltage winding 4. . - The winding end of the upper layer of the first partial winding 4a is grounded. At the bottom of the room The ends of the windings connected to each other are connected to the anodes of high voltage rectifier diodes 6. , the cathodes of this diode are each connected to the upper winding end of the next partial winding 4. It is continued. The bottom winding end of the last partial winding 4p in the chamber Kp is a high voltage terminal. form a. The winding process for the entire secondary winding 4 starts from the bottom of the chamber Kp. 2 There is one diode 6 between each chamber, so there are 16 chambers K in total. A total of 15 diodes 6 are provided. Terminal a has a high voltage of 32kV. UH occurs. At this assumed value, the bottom of each chamber is A pulse of +1100 cm, which is the same magnitude, is generated. At the upper end of winding 4, = A 1300V pulse is generated.

Therefore, along the upper layer of winding 3, a pulse with an almost constant amplitude of +1100V occurs. On the other hand, as mentioned above, opposite the winding 3 by the high voltage winding 4 In the region, i.e. also in the region of the lower end of the chamber, a pulse with a constant amplitude of +1200V Lus occurs. The pulse in winding 3 and the pulse in winding 4 are also time are also in agreement. Therefore, between the pulse in winding 1s3 and the pulse in winding 4 , there is actually no longer a voltage difference, as shown by the dash-dotted line F. A space free of electric fields can be obtained.

Moreover, the pulses at the upper end of the winding 4 are generated by the electric field, but the pulses generated there are , from the primary winding 3, which can give rise to significant displacement currents in the dielectric. It's far enough away.

The upper end of the first winding 4a is grounded and therefore does not conduct a pulse voltage; On the other hand, below the last winding 4p which is grounded via the cathode ray tube capacitance The ends also do not conduct pulsed voltages. That is, the voltage ratio of these two windings is The voltage ratio of lines 4b to 40 is different. This sets the desired amplitude ratio between the pulse voltages. In order to form the chambers in the region of It is advantageous to have only 2 turns. The primary winding 3 is preferably It is wound from litz wire to minimize losses.

FIG. 2 shows an equivalent circuit corresponding to FIG. 1. Terminal a that leads to high voltage UH , a capacitor 14 substantially formed by the anode electrode of the cathode ray tube 15; is connected. Therefore, the diode 6b connects the bottom of the chamber Ka and the chamber K in FIG. This corresponds to the first diode between the upper end of b and the end of the winding. the last dio The code 6p connects the lower end of the winding in chamber KO and the last chamber K.

This corresponds to a diode between the upper winding end of the

The primary windings 3 are arranged in sequence in the axial direction on the core 1 and connected to the terminals d. It can also be divided into several partial windings connected in parallel between them. in general, The amplitudes in the upper layer of the primary winding 3 vary with respect to the axial length. Therefore, room The degree of filling of Ka or Kp can be varied accordingly, so that the bottom of the chamber The pulses of the respective partial windings 4a to 4p have correspondingly different amplitudes. I feel relieved. In that case, the filling factor of the chamber with partial windings 4 is The amplitude of the pulse decreases from +1200V to +100OV in Figure 1. It is gradually reduced from the left end to the right end of the coil bobbin 7.2 so that It turns out.

international search report international search report Continuation of front page (72) Inventor Reihoff, Wolfgang Federal Republic of Germany D-3000 Hanover-1 Nikolai Strasse 1 (72) Inventor Sander, Hashisu Werner Federal Republic of Germany D-3 000 Hanover-71 Freidingstrasse 10

Claims (10)

[Claims] 1. A primary winding (3) and a secondary winding (4) disposed thereon, The partial windings (4a to 4p) of the secondary winding are placed in the chamber (K) of the chambered bobbin (2). The television screens arranged and interconnected via diodes (6) In high-voltage transformers for high-voltage receivers, The primary winding (3) and the secondary winding (4) are arranged so that the windings (3, 4) face each other. pulses of approximately the same amplitude and the same polarity occur in the region where the windings (3, 4) Divided and polarized so that a space with no electric field is formed between them. wrapped around A high voltage transformer characterized by: 2. The primary winding (3) is formed as a layer winding having a plurality of layers arranged one above the other. and the lower layer winding end (b) is connected to the operating voltage (UB) and the upper layer The winding end (d) of is connected to a periodic switch (13) The transformer according to claim 1. 3. The partial windings (4a to 4p) each have a winding end at the bottom of the chamber (K). , polarized to produce a positive pulse The transformer according to claim 2. 4. The number of chambers (K) and partial windings (4a to 4p) at the bottom of the chamber (K) The positive direction pulse has approximately the same amplitude as the positive direction pulse in the upper layer of the primary winding (3) 4. The transformer according to claim 3, wherein the transformer is selected to have a size such that it has. 5. The anode of each diode (6) is connected to the winding end at the bottom of the chamber (K). and the cathode is the winding end consisting of the upper layer of the partial winding (4) in the next chamber (K). It is connected to the The transformer according to claim 1. 6. The winding start end of the secondary winding (4) forms the terminal (a) for supplying high voltage (UH). Ru The transformer according to claim 1. 7. The primary windings (3) are arranged in sequence in the axial direction of the coil bobbin (2). Claim 1 comprising a plurality of parallel connected partial windings (3a to 3c). Included transformer. 8. The transformer is formed as a diode split transformer The transformer according to claim 1. 9. In the chamber (K), the pulses at the bottom of the chamber are respectively adjacent to the primary winding (3). The partial windings are filled differently so that the pulses in the windings have approximately the same amplitude has been The transformer according to claim 1. 10. The first chamber (Ka) and the last chamber (Kp) are formed by a partial winding (4). Claim 1, which is only half full compared to the other chambers (Kb to Ko) Transformer as described.