US2694784A

US2694784A - Anode voltage supply for television receivers

Info

Publication number: US2694784A
Application number: US269282A
Authority: US
Inventors: Reinhard Wolfgang; Rappold Armin
Original assignee: International Standard Electric Corp
Current assignee: International Standard Electric Corp
Priority date: 1951-02-02
Filing date: 1952-01-31
Publication date: 1954-11-16
Anticipated expiration: 1971-11-16
Also published as: BE516811A; CH299129A

Description

Nov. 16, 1954 w. REINHARD ET AL 2,694,734

ANODE VOLTAGE SUPPLY FOR TELEVISION RECEIVERS Filed Jan. 31', 1952 TO JWfEP JOURCE INVENTORS WOZ F 67 6 REM/HA Z0 ARM 1V RAP/=04 ATTORNEY United States Patent ANODE VOLTAGE SUPPLY FOR TELEVISION RECEIVERS Wolfgang Reinhard and Armin Rappold, Pforzheim, Germany, assignors to International Standard Electric Corporation, New York, N. Y., a corporation of Delaware Television picture reproduction systems are known in which an anode voltage for the picture tube of several thousand volts is produced from the energy peaks which occur in the deflecting coils. The saw-toothshaped deflection current applied to the deflection coil produces voltage peaks of several thousand volts upon the rapid return of the wave to normal voltage and the voltage thus derived is rectified and amplified as the anode voltage for the picture tube. For this purpose high tension diodes are employed as the rectifiers in the system. Because the cathodes of these diodes operate at high potential the problem of heating the cathodes has caused certain difficulties which make the insulation expensive since it may require specially designed heating transformers.

In the known type of circuit where the deflecting coils are coupled to the output of the driver circuit valve by a transformer a special heater winding may be added to the transformer for this purpose. The use of a transformer between the driver valve and deflecting coil is required only for developing the high voltage in cases in which the amplitude of the return voltage peak used for production of the anode voltage, must be limited because the voltage rating of the deflection coil is not sufliciently great. In these cases, therefore, a transformation of the voltage is desirable.

If, however, the deflection coils are constructed to withstand higher voltages or if an adequate voltage multiplier circuit is used then the voltage transformer need not be used. However, in the known circuits a special heating transformer must be supplied for the high voltage diodes in this case.

According to the present invention a system is provided which avoids these difliculties by taking the heater voltage for the diodes from the deflecting coil system.

In accordance with the principles of this invention there may be inserted a special heater winding on the iron yoke of the deflecting coils. This arrangement permits moreover that the construction of a complete unit for the deflecting system and the high voltage deflecting circuit as then the high voltage diodes and the circuit elements connected therewith (condensers and resistances) may be supported on the same structure as the deflecting coil system.

The arrangement in accordance with the invention may be used with coil systems in which yoke windings are arranged so that those parts of the windings not contributing to the deflection are arranged in a plane perpendicular with respect to the axis and partially surround the valve neck. However, special advantages result when the deflecting coil system is of the type which consists of a magnetic yoke body encircling the cathode ray beam upon which windings encircling the yoke body are mounted. This latter system has the advantage over the first described deflection system in that the deflections in the two co-ordinates are produced without overlapping coil windings so that the coil system may be constructed with a very high voltage rating. The line sweep generator may be dimensioned so that relatively high return peaks are permissible so that a single voltage doubling circuit will be suflicient for the high tension anode volt- 2,694,784 Patented Nov. 16, 1954 "ice age generation without the necessity of using a voltage transformer. Furthermore, in this type of system the arrangement of the heater winding is more simple.

A better understanding of this invention may be had from the description of a specific embodiment given below made with reference to the copending drawing in which Figure 1 is a plan view of a deflection coil system in accordance with this invention with one of the supporting plates removed, and

Figure 2 is a sectional view of the system of Fig. 1 taken along a section line 22.

Turning to the drawing, there is provided two plates 1 preferably of insulating material for supporting the entire structure arrangement, which may consist of the deflecting coil system of the high voltage deflecting circuit. The line deflecting coils 3 shown as being made up of four windings and the raster or frame deflecting coils 4, also as made up of four deflecting coils, are mounted on a ring core 2. Additional windings 5 for the generation of heater voltage for high voltage diode 6 are mounted on the same ring core 2, the diodes 6 being also fastened between supporting plates 1. Furthermore, the other circuit elements such as the condenser indicated at 7, and the resistor shown at 8 are mounted on the same supporting plates 1. Thus the circuit elements Which constitute the desired voltage doubling circuit for the diode output are all included with the deflection coil system in a common structural unit. The specific circuit connections are not fully illustrated herein as they do not constitute essential elements of the present invention. However the connections of the horizontal sweep windings and the heater coils 5 to the diode cathode is diagrammatically shown in Fig. 1.

While I have described above the principles of my invention in connection with specific apparatus, it is to be clearly understood that this description is made only by way of example and not as a limitation to the scope of my invention as set forth in the objects thereof and in the accompanying claims.

What is claimed is:

1. A television deflection circuit for use with a cathode ray tube, comprising a yoke of magnetic material, a deflecting coil system comprising deflecting windings wound around said yoke on diametrically opposed sides thereof, means to apply a saw-tooth deflection wave to said windings, a rectifier having a cathode and a cathode heater for rectifying the high voltage peaks produced by the abrupt return of said sawtooth waves, means for providing the heater voltage for said rectifier comprising an auxiliary coil wound around said core in coupling relation with said windings but substantially spaced therefrom to afford a high voltage insulating gap therebetween, and means for connecting said auxiliary coil with said heater.

2. A circuit according to claim 1, wherein the windings are each composed of a pair of partial windings, said coil being positioned between the partial windings of pairs of windings.

References Cited in the file of this patent UNITED STATES PATENTS Number Name Date 2,077,574 Maloof Apr. 20, 1937 2,164,891 Andrieu July 4, 1939 2,228,821 Hansen Jan. 14, 1941 2,261,645 Delvaux Nov. 4, 1941 2,395,966 Goldberg Mar. 5, 1946 2,406,740 Buckbee Sept. 3, 1946 2,414,925 Buckbee Jan. 28, 1947 2,428,947 Torsch Oct. 14, 1947 2,539,492 Smyth Jan. 30, 1951 2,562,941 Parker Aug. 7, 1951 2,573,017 Haworth Oct. 30, 1951