JPS5913737Y2 - Cathode aging equipment for cathode ray tubes - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an aging device for cathode aging of a cathode ray tube having multiple electron guns.

A cathode ray tube, such as a color picture tube, incorporates a plurality of electron guns formed by combining a plurality of unit electron guns, for example, three sets, each of which has a cathode and a plurality of grid electrodes arranged in series.

When aging the cathode of such a cathode ray tube,
Conventionally, three cathode terminals are connected in parallel to one end of an aging power supply, and the other end of this power supply is connected in parallel to grid electrodes of the same stage, for example, three first grid electrodes.

However, the distance between the cathode and the first grid electrode, the distance between the cathode and the second grid electrode, the heater resistance of each cathode, etc. always have small errors in accuracy. It is nearly impossible to make them the same, and therefore the aging effect, ie the activity of the resulting cathode, is not uniform.

The present invention was devised to eliminate such drawbacks of the prior art, and by connecting a plurality of cathode terminals in parallel to one end of the aging power supply via current adjustment resistors each having the same resistance value, An object of the present invention is to provide a cathode aging device for a cathode ray tube that can make the cathode current of each cathode uniform with a simple device.

Hereinafter, the details of the present invention will be explained with reference to the drawings.

1 is a cathode ray tube; 2a, 2b, 2C are three cathodes provided in the neck of the cathode ray tube 1; 3a, 3b, 3;
C is a cathode terminal 4 connected to these cathodes 2a, 2b, and 2C and protruding from the outer wall of the cathode ray tube 1;
a, 4b, 4C are the cathodes 2a, 2b,
Three first grid electrodes, 5a, respectively arranged opposite to 2C.

5b, 5C are these first grid electrodes 4a, 4b,
The first grid electrode terminals 6a, 6b, and 6C are connected to the first grid electrodes 4a, 4b, and 4C, respectively, and are connected to the first grid electrodes 4a, 4b, and 4C, respectively, and are protruding from the outer wall of the cathode ray tube 1. Second grid electrodes 7a, 7b, and 7C are second grid electrode terminals connected to the second grid electrodes 6a, 6b, and 6C, respectively, and protruding from the outer wall of the cathode ray tube 1.

Note that other grid electrodes and terminals connected to them are omitted.

Further, 10 is the cathode 2a, 2b, 2C and the first cathode.
A first aging power supply inserted between the grid electrodes 4a, 4b, 4C, one end of which is connected to the three cathode terminals 3a, 3b, 3C, respectively, with current adjustment resistors 11a, 11. b, connected in parallel via 11 C,
The other end is connected in parallel to the first grid electrode terminals 5a, 5b, 5C, and 12 is a second terminal inserted between the cathodes 2a, 2b, 2C and the second grid electrodes 6a, 6b, 6C.
is an aging power supply, one end of which is connected in parallel to the cathode terminals 3a, 3b, 3C via the above-mentioned current adjustment resistors 11a, 11b, 11C, and the other end connected to the three second grid electrode terminals. 7a, 7b, and 7C are connected in parallel.

Then, the above-mentioned current adjustment resistors 11a, 11b
, 11 C and each of the above terminals 3a, 3b, 3C, 5
The connection devices for a, 5b, 5c, 7a, 7b, and 7c are collectively incorporated into the device.

The operation of this device will be explained with reference to the graph in FIG.

In this graph, the horizontal axis shows the cathode voltage in units of ■, and the vertical axis shows the cathode current in units of rnA.Curve IMAX:y curve IMIN9Curve L BOG is the relationship between cathode voltage and cathode current. This is a characteristic curve showing the maximum, minimum, and bogey of the cathode current fluctuation due to the non-constant resistance inside the tube.

Then, the conventional technology, that is, the current adjustment resistor 11 a,
When the resistance values of 11b and 11C are both 0, the cathode voltage supplied from the aging power supply 10 is directly applied to all the cathode terminals 3a, 3b, and 3C, and for example, as shown by the chain line R8, All terminals 3 have a power supply voltage of
It is uniformly applied to a, 3b, and 3C.

Then, the curve I MAX and the curve IM intersect with the chain line R8.
The difference from IN, that is, the fluctuation range of the cathode current is a, which is large.

On the other hand, current adjustment resistors 11 a, 11 b, 11
When the resistance values of C and Q are adjusted to 10 K and Q,
The voltage applied to the cathode terminals 3a, 3b, and 3C varies depending on the cathode current, in other words, the tube resistance of each electron gun.

Therefore, if the corresponding points of the cathode voltage and cathode current are dotted, they are as shown by the chain line R1o.

The intersection of the dashed line R1o and the curve IMAX is the maximum current value in this case, and the intersection of the dashed line R1o and the curve IMIN is the minimum current value in this case. This is much smaller than the difference a in current value.

That is, by inserting current adjustment resistors 11a, 11b, and 11C having the same resistance value into the cathode terminals 3a, 3b, and 3C, it was possible to reduce the fluctuation width of the cathode current.

As described above, the cathode aging device of the present invention is an aging device that is installed in a cathode ray tube having a plurality of electron guns, and in which an aging current is passed between the cathode terminal and the grid electrode terminal of the cathode ray tube. Since the cathode terminals of the cathode terminals are connected in parallel to one end of the aging power supply through current adjustment resistors having the same resistance value, the difference in cathode current between the cathodes is reduced, thereby aging each cathode equally. is possible,
Moreover, it has the advantage of a simple structure and easy operation.

[Brief explanation of the drawing]

FIG. 1 is a wiring diagram of an embodiment of the cathode aging device for a cathode ray tube according to the present invention, and FIG. 2 is a graph illustrating the same operation. 1...Cathode ray tube, 2a, 2b, 2C...
・Cathode, 3a, 3b, 3C--Cathode terminal, 4a, 4b, 4C, 6a, 6
b, 6 C...-grid electrode, 5a, 5b, 5
C, 7a, 7b, 7C... Grid electrode terminal, 10
．． 12... Aging power supply, 11 a, 1
1 b, 11 C... Resistor for current adjustment.

Claims (1)

[Scope of utility model registration request] In an aging device installed in a cathode ray tube having multiple electron guns, in which an aging current is passed between a cathode terminal of the cathode ray tube and a grid electrode terminal, the plurality of cathode terminals are adjusted to each have the same resistance value. A cathode aging device for a cathode ray tube, characterized in that it is connected in parallel to one end of an aging power source via a resistor.