KR800000293B1 - Circuit arrangement including a line deflection circuit - Google Patents

Abstract

A cct. arrangement for TV display device is composed of a line deflection cct. having resonance cct. which comprises trace and retrace capacitors(Ct,Cr) and line deflection coil(Ly) and having 1st line frequency control switch for supplying across voltage of the trace capacitor to the deflection coil during the retrace period, a voltage supply cct. having 1st winding and for supplying voltage to the deflection cct. and a 2nd winding. The 1st and 2nd windings are wounded on a similar magnetic core, thus saving the cost of inductive elements.

Description

Circuit arrangement including line deflection circuit

1 is a basic circuit diagram of a first embodiment of an apparatus according to the present invention.

2 is a waveform generated in the circuit of FIG.

3 shows an equivalent circuit diagram of the device part according to FIG. 1.

4 is a graph that serves to select a parameter.

5 is a change in current flowing through the device of FIG.

6 is a basic circuit diagram of a second embodiment of the device according to the present invention.

7 is a schematic diagram of a transformer used in the present invention.

8 and 9 show another embodiment of the apparatus of the present invention.

The present invention relates to a circuit device including a line deflection circuit for generating a line frequency sawtooth wave deflection current through a line deflection coil in a television display device and a voltage supply circuit for switching at the line frequency, wherein the line deflection circuit includes a deflection coil and a trace. A capacitor, a retrace capacitor, a first wire frequency control switch, and at least one coil wound around a transformer having a core of a magnetic material. The voltage supply circuit is a coil of an inductive element coupled to a line deflection circuit through a diode. The coil is coupled to the voltage power supply by a second control switch.

These circuits were described in "IEEE Transactions on Broadcast and Television" August 1972, Vol. BRT-18, No. It is described on pages 3,177-182, which is a combination of a line deflection circuit and a switched voltage supply stabilization circuit, where the control switch fully fulfills these functions.

Such known circuit arrangements have the advantage that they can be operated by unstable supply voltages and can generate satisfactorily stabilized deflection currents and stabilized high voltages (EHT) and possibly auxiliary voltages, where stabilization is a switch. It is obtained by controlling the duty factor of.

According to the above bulletin, the EHT coil is coupled to the coil of the induction element, where high amplitude EHT coil pulses are generated during the retrace time.

These pulses are fed to the rectifier to generate EHT for the accelerated anode of the television receiver. The disadvantage at this stage is that the inductor must be able to accumulate a lot of power, so having a high inductance is expensive.

Another disadvantage is as follows. In practice, the inductive element sometimes has two coils, a primary coil inserted between the switch (transistor) and the connection point of the second diode and the terminal of the voltage power supply, and a secondary coil coupled to the deflection network through the third diode. This is it.

The third diode conducts during the portion of the trace that the transistor does not conduct. At this time, the EHT coil is coupled to the secondary coil of the induction element, and the EHT coil is coupled to the primary coil of the induction element because the third diode does not conduct during the other part of the trace time at which the transistor conducts. Since the leakage inductance between the EHT coil and the primary coil and the aforementioned leakage inductance between the EHT coil and the secondary coil are inevitably different from each other in the winding technique and the assembly technique, the series resonance of the network constituted by the capacitance to the ground and the leakage inductance The frequency will be different during the aforementioned two parts of the trace time. As a result, higher harmonic tuning of the inductive element considered to be a transformer is not possible, resulting in parasitic oscillations.

Another disadvantage of the above steps is that the voltage across the two coils of the inductive element changes one step at the moment the transistor conducts.

In the above-described series resonant network, current is generated so that parasitic oscillations occur after the aforementioned moment. It can also change at this moment, which depends on the supply voltage.

The above disadvantages can be eliminated if the EHT coil is coupled to one coil coupled directly to the deflection network or through a capacitor.

This step is also contained in the aforementioned newsletter (Fig. 8, page 181). Since current flows through this coil throughout the trace time, the leakage inductance between them and between the EHT coils does not change, and the voltage across it does not change stepwise.

However, this step also has an obvious disadvantage: not only does the circuitry contain an inductive element, but also has a separate transformer, allowing color TVs to pass up to 25KV × 2mA = 500W of EHT power. This can be very expensive.

It is an object of the present invention to make these expensive components economical, and for this purpose the circuit arrangement according to the invention is characterized in that the coil of the induction element is also wound around the core described above.

The present invention is based on the following facts. For example, a voltage that varies as follows exists across each coil of the inductive element. That is, during the retrace time, this voltage is proportional to the retrace pulse, and has a predetermined value during the portion of the trace time during which the transistor is not conducting, and another value during the rest of the trace time.

On the other hand, there is a voltage in the transformer coil coupled to the deflection network during the retrace time that is equal to the retrace pulse and virtually unchanged during the trace time. When a transformer coil and an induction element are coupled to each other according to the present invention, currents flow through them, which is generated by the coupling and, inter alia, depends on the difference between the voltage across the transformer coil and the voltage across the induction element. However, the current described above does not affect the voltages described above in order to exist across coils in which voltages of different shapes are combined. These currents cause virtually no losses and have no detrimental effect when the device design is properly selected. This is because the operation of the circuit device does not change even if one of the separate currents through the third diode flows in the blocking direction and the diode is blocked.

On the other hand important advantages have been obtained due to the process according to the invention.

In a known device, a certain minimum power had to be consumed for satisfactory operation. In the device according to the present invention, since this minimum power can be greatly reduced, losses in the device are not actually derived from any voltage source. It turns out that it is close to the theoretical situation. This can be obtained by appropriately selecting the two parameters that determine the device, where the two parameters are the coupling coefficient and transformer ratio between the coil of the inductive element and the transformer coil. By selecting the same parameters, the maximum intensity of the current flowing through the transistor, i.e., at the end of the trace time, and the preliminary magnetization of the core can be reduced and compromised so that all requirements can be met by a well-known method.

If the circuit arrangement is constructed as in the above-mentioned newsletter, that is, if the second switch is replaced by one transistor, the first switch is connected to the second diode and the series device of the above-described transistor and third diode. The deflection current flows through the second diode during one portion of the trace time, and the deflection current flows through the second device and the third diode in series during the other portion of the trace time.

However, other embodiments are possible, which are slightly different from those described above, but fall within the scope of the present invention, where there are no retrace pulses but square wave voltages are present across the coils of the inductive element.

The invention also relates to an EHT transformer, characterized in that the transformer has a magnetic core having a first and a second leg, wherein the two coils are tightly coupled and wound on the first leg, The other coil and the EHT coil are wound on the second leg.

Referring to the present invention in detail based on the accompanying drawings as follows.

The circuit device of FIG. 1 includes a drive stage Dr, which receives a signal from a line oscillator (not shown) and supplies switching pulses to the base of the switching transistor Tr. One end of the primary coil L ₁ of the transformer T is connected to the collector of the npn type transistor Tr, and the other end is connected to the (+) terminal of the DC voltage power source B, and the transistor Tr The emitter of is connected to the negative terminal.

This negative terminal may be connected to the ground of the circuit arrangement.

The trace capacitor Ct is connected in series with the linear deflection coil Ly of the circuit device of FIG. 1 in a television display device (not shown in the drawing), and has a diode D ₁ and a retrace capacitor having a conduction direction as shown in the drawing. Cr) is connected in parallel with the above-described series connection device. The capacitor Cr may be connected in parallel to the coil Ly. The four devices only show a basic circuit diagram with the main components of the deflection section. This deflection can be equipped with one or more transformers for the mutual coupling of the elements, for example in a known manner, and can also be provided with devices for doing such as centering correction and linearity correction.

The secondary coil (L ₂₎ of the transformer (T) has a diode (D ₃₎ and arranged in series, the cathode of the diode (D ₃₎ is connected to the element junction (A) a (D _1, Cr, Ly) diode ( D ₂ ) is connected to the anode. The cathode of the diode D ₂ is connected to the collector of the transistor Tr, and the tertiary coil L ₃ of the transformer T is connected to the point A through the capacitor C ₁ . The other coils are wound around the core of the transformer T, across which the voltages acting as supply voltages to the other parts of the television display device. One of these coils, coil L ₄ , is shown in FIG. 1, which generates a positive DC voltage across the smoothing capacitor C ₂ with the help of rectifier D ₄ . One of these coils, for example coil L ₄ , is the EHT coil so that the voltage across capacitor C ₂ becomes the EHT for the accelerated anode of the water pipe (not shown in the figure). The remaining terminals of the coils L ₂ , L ₃ , L ₄ are grounded, and the polarity of the coils (shown in the transformer T) is indicated by dots (.) In the figure.

Firstly, when the fact that the coil L ₃ is coupled to the induction elements L ₁ , L ₂ of the known device cannot be taken into account, the described circuit arrangement works like the circuit arrangement in the aforementioned newsletter. It is summarized as follows. Diode D ₁ conducts during the first part of the line trace time. The voltage across the capacitor Ct appears across the deflection coil Ly through which the sawtooth deflection current iy flows.

When the transistor (Tr) to conduction at which point, when in the middle of the trace period, the current (iy) and change its direction, and a diode (D ₁₎ Since the breaking current (iy) is a diode (D ₂₎ and the transistor It flows through (Tr). At the end of the trace time, the transistor Tr is shut off. An oscillation that is a retrace pulse is generated across the capacitor Cr, while energy stored in the coil L ₁ and derived from the power source B generates a current through the diode D ₃ .

When the voltage across the capacitor Cr becomes zero again, the diode D ₁ becomes conductive, which is the beginning of a new trace time. The diode D ₃ remains in the conductive state until the transistor Tr becomes conductive, and the energy in the coil L ₂ is transferred to the coil L ₁ .

The stabilization is performed as follows. For example, the voltage applied to the capacitor Ct is fed back to the driving circuit Dr. In this circuit, the comparator and the modulator cause the conduction time of the transistor Tr to change so that It also ensures that the amplitude of the deflection current remains constant.

2a shows a voltage V _A applied to the capacitor Cr,

2b shows the voltage V ₂ at the junction of the coil L ₂ and the diode D ₃ ,

In FIG. 2c the voltages Vc at the collector of the transistor Tr are represented as a function of time. T _H represents the line period, τ ₁ represents the retrace time, τ ₂ of the period T _H is when the transistor Tr is not conducting, and τ ₃ = δ T _H is the period when the transistor conducts ( T _H ) moiety. δ is the ratio of time τ ₃ to the period T _H.

이다. 전압(V_C)는 T₁동안 pV₂＋V_B이다.During τ ₁ and τ ₂ , the diode D ₃ conducts and the voltage V _A and V _{2 are the same} , that is, during τ ₁ , the retrace pulse has amplitude (V) and becomes zero for τ ₂ . . At the moment when the transistor Tr becomes conductive, that is, at the transition time t ₁ between τ ₂ and τ ₃ , the voltage Vc is actually zero. The voltage V _B from the power source B is generated across the coil L ₁ . If the ratio of the transformation between coil L ₂ and L ₁ , that is, the ratio between the number of turns of coil L ₂ and the number of turns of coil L ₁ is 1: P, voltage V ₂ is τ ₃ .

to be. The voltage V _C is pV ₂ + V _B during T ₁ .

V ₀ is the DC voltage across the capacitor (Ct) and the capacitor has a sufficiently large capacity, or V ₀ is the DC voltage component of the voltage across the capacitor (Ct) and the capacitor is of relatively low capacity to perform the so-called S correction. In this case, V ₀ is an average value of the voltage V _A. In fact, the DC voltage component cannot exist across the coil Ly.

Here we apply the following equation:

Since the average value of the voltage across the coil L ₂ is also zero,

If we remove the integral from the above two equations,

At a given value of the ratio δ, P the diode D ₂ will conduct for τ ₁ . Since diode D ₃ conducts for the same time, coils L ₁ and L ₂ will be short-circuited by diodes D ₂ and D ₃ , and the retrace pulse across capacitor Cr is blocked and deflected. Distortion will occur in the current. Processes are described in Dutch Patent Application No. 7,303,252 (PHN6794), that is, Korean Patent Application No. 1700 1700, by which the effect can be reduced. For example, a transistor that is blocked for a time τ ₁ is connected in series with the diode D ₂ .

The capacitor C ₃ is arranged between the ends of the coils L ₁ and L ₂ , or between their intermediate taps, which prevents parasitic oscillations caused by leakage inductances present between the coils described above. In this case, there is no line frequency voltage in the capacitor C ₃ because of the purpose. FIG. 1 shows the case where P = 1. Similar to the capacitor Ct, the DC voltage or the DC voltage component is present in the capacitor C ₁ , which is equal to the voltage V ₀ , so that the voltage across the coil L ₃ is the shape and voltage of FIG. It will be clear that there is a difference that the same and same zero axis should be raised up by the value of V ₀ .

In the present invention, the coils L ₁ and L ₂ on one side and the coils L ₃ on the other side are coupled to each other as shown in FIG. Although they are not affected by the combination, they are based on the recognition of the fact that they are combined.

The coupling of the coils of the transformer T cannot affect the "hard" voltages V ₀ and V _B , where "hard" refers to the application of an external voltage. However, the currents flowing through the other coils are affected.

)와 직렬 연결되는데, 그 유도기는 코일(L₁과 L₂)간의 누설인덕턴스를 나타낸다. 그래서 등가 회로도는 3개의 코일(ℓ₁,ℓ₂,ℓ₃)로 구성되는데, 그것들은 상호 결합계수 1을 가지며,ℓ₂에 대한 ℓ₁의 변압비는 전술한 비율 P와 같고 ℓ₂에 대한 ℓ₃의 변압비는 n과 같다.3 shows an equivalent circuit diagram of the portion of FIG. 1. As in the above bulletin, the coupling between the coils L ₁ and L ₂ is very tight. Since there is a capacitor C ₃ , the coupling coefficient between these coils can be considered as 1. Coupling coefficient between the coils (L ₂ and L ₃ ) is not 1, only one part of the tertiary coil is connected to the secondary coil so that the coupling coefficient is 1, and the tertiary coil is not connected to the secondary coil.

Is connected in series, and the inductor represents the leakage inductance between the coils L ₁ and L ₂ . So, an equivalent circuit is composed of three coils (ℓ _1, ℓ _2, ℓ _3), they have a mutual coupling coefficient 1, the variable pressure ratio of ℓ ₁ to ℓ ₂ is the same as the above-described ratio P to ℓ ₂ The transformer ratio of l ₃ is equal to n.

)는 코일(ℓ₃)에 직렬연결되고, 코일(ℓ₃)의 인덕턴스는 다른 코일들에 부하가 없을때 제1도에서의 코일(L₃) 양단에 측정된 값이다.Inductor having a value of L is ₁ there is connected in parallel to the coil ₍₁ ℓ), the value is a value measured across the coil (L ₁₎ of the diagram (1) the absence of a load to the other coil. The above-described inductor (

) And the inductance of the series connection, a coil ₍₃ ℓ) to the coil ₍₃ ℓ) is the value of the coil (L _3), measured at both ends of the diagram (1) the absence of a load to the other coil.

From this we can derive the following equation:

Where k is the coupling coefficient between the coils L ₂ and L _{3 in} FIG.

Without this coupling (k = 0) currents i ₁₀ , i ₂₀ , i ₃₀ flow through the coils L ₁ , L ₂ , L ₃ , respectively, where currents i ₁₀ and i ₂₀ Are the currents in the above-mentioned newsletter and current i ₃₀ is sawtooth wave like current iy. Since the coils L ₂ and L ₃ are coupled to each other, separate currents i _1k , i _2k , i _3k flow through the coils, respectively.

Assuming that the device consists of ideal inductors, capacitors, and semiconductors, these separate currents do not increase any losses.

In practice, this increase in losses remains small. It is also possible to select the above mentioned parameters n and k appropriately so that the operation of the device is not adversely affected, which will be described next.

The currents i ₁ = i ₁₀ + i _1k , i ₂ = i ₂₀ + i _2k , i ₃ = i ₃₀ + i _3k , respectively, flow through the l ₁ , l ₂ , l ₃ coils of FIG. 3.

During τ ₁ i ₁ = 0, and the currents i ₂ and i ₃ change as follows.

for τ ₂ i ₁ = 0,

for τ ₃ i ₂ = 0,

In order not to the operation of the device is not interrupted, the current (i ₂₎ is always must flow in the positive direction in FIG. 3, even when the change (△ i ₂₎ is always negative, at τ _2. 3 shows that the current i ₁ must also be positive. Current (i ₁₎ the only condition to be met because the positive or negative for the change in τ ₃ (△ i ₁₎ In the expression (2) described above flows for τ ₃ are as follows.

0일 때에는 i₁이 t₁(이 순간은 δ에 좌우되고 결국 V_B에 좌우된다)에서 0보다 크거나 같아야 하며,△i₁

0일 때에는 이 트레이스 시간이 끝나는 순간(t₂)에서 0보다 크거나 같아야 한다. 전류(i₁)의 평균값은 장치에서 정해진 전력의 계산으로부터 얻어진다.△ i ₁

If 0, i ₁ must be greater than or equal to 0 at t ₁ (this moment depends on δ and eventually V _B ), △ i ₁

If zero, it must be greater than or equal to zero at the end of this trace time (t ₂ ). The average value of the current i ₁ is obtained from the calculation of the power determined in the device.

여기서

here

는 2차 측으로 변형된 전술한 평균값이다.

Is the above-described average value modified on the secondary side.

이며, 이는 파라메터(k)와 무관하다.Substituting in equation (1):

This is independent of the parameter k.

Applying the above conditions for the minimum possible value of δmin:

On the other hand, when applied to the maximum possible value of δ max,

WL ₁ = (WL ₁ ) ₀ R ₂ .

In this equation, (WL ₁ ) ₀ is the value of WL ₁ when there is no bond (k = 0),

일때에는 δmax=0.8(트랜지스터(Tr)는 트레이스 시간이 시작하는 순간(t₀)에서 전도하게 된다)이고, δmin=0.4(t₁은 트레이스 시간의 중간에서 교차한다)이다.Retraceviga

Δ max = 0.8 (transistor Tr will conduct at the beginning of trace time t ₀ ), and δ min = 0.4 (t ₁ intersects in the middle of trace time).

As such data can be seen in the graph of FIG. 4, in which the coefficients R ₁ and R _L are represented as a function of n together with the parameter k.

The fourth turning to show the values are given for a ratio (n) for a given value of the coupling factor (k), the values are located to the right of which is located in the upper part of the curve which the R ₁ R ₂ curve. The values given by these curves show the minimum value of the ratio of WL ₁ to the aforementioned coefficient (k) and (WL ₁ ) ₀ when there is no combination in which the device can operate normally. It has been found that the parameter (n and k) values can be chosen such that the above ratio is less than one.

This case occurs for example when k = 0.71 and n = 0.3, ie when R ₁ = R ₂ = 0.67 (point M), and more generally for the shaded portion of the graph (k = 0.71). Larger binding coefficients are possible, where k = 0.84 and n = 0.4, where R ₁ = R ₂ = 1 (point N), which is not improved but is never regressed than without binding. On the other hand, in the case of point P, that is, k = 0.71, n = 0.6, and R ₁ = 1.35, some deterioration occurs.

This turns out that the parameters k and n can be arbitrarily selected. The fact that the minimum power consumption (W) for a given physically L ₁ (in a given amount of ions and copper) is less than when L ₂ and L ₃ are not combined with each other or with the same L _1. Can be. Some power consumption is necessary because currents i ₁₀ and i ₂₀ always flow in the positive direction without coupling. For example, due to the loss in the deflection coil Ly or the load connected to the capacitor Ct. If the combination is the (i _1k and i _2k) separate current flows, they will be generated by the energy stored in the coil (L ₃₎ is induced in the coil (L ₁ and L _2), the currents the diode (D ₃ ) In the negative direction without blocking.

As a result, part of the supplied energy is fed back to the power source B again. Therefore, the power consumption must be minimal, as well as the operation of the device must not be affected by the coupling, ie the diode D ₃ must be conducting at τ ₂ .

의 다른 값들에 대해, 즉 공급전압(V_B)의 다른 값들에 대해 나타낸다.The fifth turning the time τ ₁ and τ ₂ changes in current ₍₁ pi) for change of the current (i ₂₎ and for a τ ₃

For other values of ie, for other values of supply voltage V _B.

일때 △i₁값이 0임을 나타낸다. 이때 전류 (pi₁)은 τ₃동안 pi₀값을 갖는다(제5b도 참조).In FIG. 5A, the change Δi ₁ in Equation (2) is positive, and in FIG. 5C, this value is negative. Equation (2) is

When Δi ₁ is 0. At this time, the current pi ₁ has a pi ₀ value for τ ₃ (see also FIG. 5b).

This value, which is the same in Figs. 5A, 5B, and 5C, is proportional to the power consumption W, so that when W is low, the value is also very small. Since the current i ₂ is slightly smaller than pi ₀ after the instant t ₂ , i ₀ cannot be zero but can be very small. This means that the device approximates a theoretical situation in which no energy is actually received from the power source B and there is no loss. Another important point is related to the maximum collector current of transistor Tr. It is assumed that the current iy flowing through the diode D ₂ and the transistor Tr has the maximum intensity at the end t ₂ of the trace time. The current flowing in the coil L ₁ and the current flowing in the coil L ₃ also flow through the transistor Tr.

For a time τ ₃ , the collector current i _C becomes

i _C = i _y + i ₁ + i ₃ = i _y + (i ₁₀ + i _1k ) + (i ₃₀ + i _3k ) = i _y + (i ₁₀ + i ₃₀ ) + (i _1k + i _3k ) = i _C0 + i _Ck

Where i _C0 and i _Ck represent collector currents with and without coupling between coils L ₂ and L ₃ , respectively. With proper selection of the parameters (k and n), the current i _Ck can be zero or negative at the time of t ₂ so that the collector peak current can have a better value. This is due to the fact that during the trace time, the current i ₃ becomes a sawtooth wave because the voltage across the coil l ₂ and eventually the voltage across the coil l ₃ is a square pie. By appropriately choosing the parameters n and k, the intensity at the instant t ₂ can be made negative but not so large that the current i _C becomes zero, in which case n should not be too small. This is in contrast to the case of FIG. However, this figure shows that when n = 1 and k = 0.11 and k = 0.5, the coefficients R ₁ are 1.6 and 1.2, respectively, indicating that the minimum power is 60% and 20% more than without the coupling, respectively.

If n is a larger value and k = 0.5, then the coefficient R ₁ cannot be greater than 1.33. Thus, a satisfactory compromise between the need for low power consumption and the need for a lower maximum collector current is possible by choosing a lower value of k, of course if the maximum collector current at a higher k value is much lower than its allowed peak value. The value does not need to be low.

Another advantage of the process according to the invention is that the magnetizing current of the transformer T can be reduced. When there is no coupling, the current with maximum intensity at the instant t ₂ flows through the coil L ₁ . As a result, saturation of the magnetic body constituting the core may occur such that the inductance of the coil L ₁ is reduced.

As a result, the above-described current is still larger, thus increasing the collector power consumption of the transistor Tr. However, this saturation may occur less or not at all because the current i _C may be reduced at the instant t ₂ as a result of this coupling. By reducing the number of coil turns or making the cross-sectional area of the core smaller, not only the transistor is securely protected but also the desired inductance of the coil L ₁ can be obtained.

The EHT coil L ₄ is more tightly coupled to the coil L ₃ than the coils L ₁ and L ₂ , which can be realized by using a core that actually consists of two U-shaped cores, where the coil ( L ₁ and L _{2 are} mounted on one leg and coils L ₃ and L _{4 are} mounted on the other leg. As a result, a voltage that does not change rapidly at the time t ₁ is present at both ends of the coil L ₄ . A method of justice winding, for example a so-called higher harmonic tuning, may be used. In the same way, other coils (not shown in the figure) of the transformer T may be more closely coupled to the coil L ₃ than to the coils L ₁ and L ₂ .

FIG. 6 shows a variant of the device wherein the terminal of the EHT coil (L ₄ ) terminal, which is not connected to the diode (D ₄ ), is connected to point A without grounding. The result is an increase in the voltage to be rectified. Tabs are provided on coil L ₃ , between which series circuits Ly and Ct are arranged, while auxiliary voltages can come from other taps. One of these voltages is fed back to the modulator in the drive circuit Dr, which affects the time τ ₃ for the purpose of stabilization. A separate coil L ₅ of transformer T may be used for this purpose.

When the transformer T is designed with a small coupling coefficient k, a small transformer can be used by using a so-called magnetic shunt.

7 shows such a structure. It shows that the magnetic flux generated by the coils L ₁ and L ₂ is mainly present in the left and center legs of the core, ie the magnetic shunt. The right leg with coils L ₃ and L ₄ wound can reduce magnetic flux to a large extent when sufficient magnetoresistance is provided in the form of an air gap. In the same way one air gap can be provided to the left leg.

In the embodiment according to FIG. ₁ , the number of turns of the coils L ₁ , L ₂ , L ₃ is 230, 230, 140 and the inductance of L ₁ is about 12 mH, and the coupling coefficient between the coils L ₂ and L ₃ ( k) was about 0.63. In addition, the core was formed of two air gaps each having a width of 0.6 mm without magnetic shunt, and the voltage (V ₀ ) was stabilized at 140 V when the voltage (V _B ) varied between 230-345V and the deflection coil (Ly) The inductance of was about ₁ mH and was Ct-680 nF and C _1-2 µF.

The capacitance of the capacitor C ₁ should not be too low, because otherwise the voltage across the coil coupled to the coil L ₃ becomes parabolic during the trace time and cannot be used for trace rectification. In this example, the EHT coil was tuned to the fifth harmonic.

Another suitable design of the circuit arrangement according to the invention can be obtained by using air gaps that are not equal in width in FIG.

If the transformer T has the same air gaps, the inductance of the coils L ₂ and L ₃ is proportional to the square of the number of turns. The inductance of L ₂ depends on the minimum power consumption, while the number of turns of coil L ₃ is determined by the desired EHT. If the air gaps are different, the ratio of inductances will no longer be equal to the ratio of the square of the number of turns, making a new selectable parameter available. This parameter can be selected such that the maximum collector current of transistor Tr can be reduced while maintaining the advantages of the process according to the invention. For this purpose, the widest gap is provided on the left leg where the coils L ₁ and L ₂ are wound, and the coil L ₅ , which is subjected to the voltage to be fed back to the drive circuit Dr, is also provided on the same leg.

The circuit arrangement of FIG. 1 can be replaced by the circuit arrangement of FIG. 8A simply without changing its characteristics. The collector-emitter path of the second transistor Tr 'is connected in parallel with the diode D ₁ , the base of which is controlled by the secondary circuit of the drive circuit Dr, for example the drive transformer T'. Another secondary coil of the transformer T 'controls the base of the transistor Tr.

Transistor Tr 'provides a path for deflection current iy during the second portion of the trace time.

The fact that the base of the transistor Tr 'receives a signal during the first half of the trace time, ie at the instant t ₁ , does not matter. This is because current iy flows through diode D ₁ in any way.

The transistor Tr 'may be selected in form so that the task of the diode D ₁ is taken over by the collector-base diode of the transistor so that the diode D ₁ can be omitted. This diode can also be omitted because the current iy no longer flows through the diode D ₂ and the diode remains blocked for the duration of time.

Figure 8b shows one variant, in which the transistor Tr 'is not controlled by the driving circuit Dr (which causes a very high load on the transistor) and is controlled by the coil L ₆ of the transformer T. do. Coil L ₆ is more tightly coupled to coils L ₁ , L ₂ , L ₅ than coils L ₃ and L ₄ , for example, coils L ₁ , L ₂ , L ₅ , L ₆ It is mounted on one leg of the transformer T and coils L ₃ and L _{4 are} mounted on the other leg.

This transformer is constructed with or without magnetic shunt, depending on its design (in FIGS. 8a and 8b, the core of the transformer T is shown in a rectangle for clarity). This structure has the advantage that the deflection of the device, ie the coils L ₂ , L ₃ , L ₄ , L ₆ and the components connected thereto, can be separated from the mains, but the power supply is not. This means that the above-mentioned idle ends of the coils and elements Tr ', Cr, Ct, etc. are grounded, while the idle ends of the coils L ₁ , L ₅ and elements Tr, B, etc. It means that it is connected to the track. In this case, the capacitor C ₃ (indicated by the dotted line) should be omitted.

In the above-described embodiment, diode D _{3 is} connected to point A, but in the newsletter mentioned in the preamble another embodiment is described, where diode D ₃ is connected to the junction of the inductor and the capacitor, The other terminal of the inductor is connected to point A and the other terminal of the capacitor is grounded.

The operation of this embodiment is substantially the same as the above-described embodiment except that the waveforms of Figs. 2b and 2c are replaced by square waves. In this case the process according to the invention can be used as shown in FIG. 9A since the generated voltage is also "light". However, since the difference between the voltages is larger, the separate currents generated by the coupling will be larger than in the above-described embodiment, so that the parameters k and n will be selected differently.

In FIG. 9A, the above-described inductor L ₇ is wound around the core of the transformer T, while C ₄ is the above-described capacitor. Coils L ₁ and L ₂ are on one side and coils L ₄ and L ₇ are on the other side.

In the same manner as in the embodiment of FIG. 8A, transistor Tr 'of FIG. 9A can be connected in parallel with diode D ₁ , where the diode itself can be replaced by the collector-base diode of the transistor. This is shown in Figure 9b, where also the coil L ₆ is wound around the core of the transformer T to control the base of the transistor Tr '.

In FIG. 9B, elements Tr, L ₂ , D ₃ , and C ₄ constitute a switch-type voltage power supply. A variant thereof is shown in FIG. 9e, where the voltage source consists of elements (Tr, L ₂ ', D ₃ ', C ₄ '), in which the device is arranged in series rather than in parallel with the deflection to be considered a load. do. The following facts are noted here. That is, even if the collector voltage of the transistor Tr 'becomes too high due to a defect in the transistor Tr whose collector-emitter path will form a short circuit, the transistor Tr' is still protected. This is because the control voltage drops in the case described above.

Claims (1)

A resonant circuit having a line deflection coil, a trace condenser and a retrace condenser, and a first wire frequency control switch for supplying a voltage present between both ends of the trace trace capacitor to the deflecting coil which is supplied during the retrace time. A line deflection circuit for generating a sawtooth wave deflection current having a line frequency having a trace time and a retrace time in the circuit; A second wire frequency control switch having a variable conduction time and a first winding which is coupled to the deflection circuit via the supply diode and coupled to the voltage source by the second control switch, and supplies a voltage to the deflection circuit. A voltage supply circuit; Coupled with a deflection circuit, it has a second winding that has a retrace pulse during the retrace time and a voltage of a line frequency that usually does not change during the trace time, so that the first and second windings are on the same magnetic material core. A circuit arrangement in a television receiver characterized by being wound around.

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