JPS60259076A - Degaussing element comprising two elements - Google Patents

Abstract

PURPOSE:To obtain a degaussing element comprising two elements small in residual current in which the thermal coupling and contact state of two positive characteristic thermisters does not change for a long time by bonding the two kinds of positive characteristic thermisters different in Curie point to a metallic common terminal board. CONSTITUTION:A series circuit comprising an AC power supply and a degaussing coil is connected between the common terminal board 16 and a lead wire 17, and the same power supply is connected to the common terminal board 16 and a lead wire 18 to connect the power supply. Since the resistance of the positive thermisters 10, 11 is low at first, a large current flows to the both, they are heated gradually by the current, and when each temperature reaches the Curie temperature or above, the resistance rises rapidly and the current is attenuated. Since a large current flows to the degaussing coil and is attenuated gradually, an alternate magnetic field is applied to a color cathode ray tube while its amplitude changes from a large to a small value, the demagnetized magnetic field is eliminated.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application The present invention relates to a two-element degaussing element using a positive temperature coefficient thermistor, which is used in series with a degaussing coil used in a cathode ray tube of a color television.

Conventional Structure and Problems Conventionally, in this type of two-element demagnetizing element, as shown in FIG. , silver baked electrodes on both sides 3
An intermediate terminal plate 4 such as a silver-plated brass plate is sandwiched between a second positive temperature coefficient thermistor 2 having a temperature higher than that of the first positive coefficient thermistor 1, and the positive characteristic of both The thermistor 1.2 is crimped with a spring terminal 5°6 such as a silver-plated bronze plate, and these are inserted into the case 7 made of insulating resin.Terminal plate 4, 5°6 on the above side.
protrudes from the bottom of the case 7 to the outside through a through hole. A lid 8 is provided on the small case 7 and is fixed with adhesive or the like.

FIG. 2 shows a circuit in which this two-element negative element is used.

9 is a demagnetizing coil. When the switch SW1 is closed, a current flows through the series circuit of the positive temperature coefficient thermistor 1 and the demagnetizing coil 9. Initially, since the resistance value of the positive temperature coefficient thermistor 1 is small, a large alternating current flows through the demagnetizing coil 9, and at the same time The positive temperature coefficient thermistor 1 also generates heat due to the current, and when the temperature of the positive coefficient thermistor 1 reaches one Curie, the resistance value increases rapidly.
The current also decreases accordingly. In this way, since the alternating current gradually decreases, a large alternating magnetic field to a gradually smaller alternating magnetic field is applied to the degaussing coil 9, and the magnetic field that has magnetized the cathode ray tube is accordingly erased. but,
Since the switch SW1 is always closed, a minute current flows through the degaussing coil 9, and a minute alternating magnetic field is always applied to the cathode ray tube, resulting in color blurring and flickering. In recent years, high-definition cathode ray tubes have been required, and the demand for lowering this residual current has become stronger. Therefore, a two-element demagnetizing element has been devised. This is done by bringing the second PTC thermistor 2, which has a higher Curie temperature than the first PTC thermistor 1, into close thermal contact with the first PTC thermistor 1 in FIGS. A voltage is applied to the series circuit of the positive temperature coefficient thermistor 1 and the degaussing coil 9, and at the same time a voltage is applied to the second positive coefficient thermistor 2.
The positive temperature coefficient thermistor 2 is heated to a temperature higher than the first positive coefficient thermistor 1, and the heat is used to increase the temperature of the first positive coefficient thermistor 1.
The residual current of the first positive temperature coefficient thermistor 1 can be extremely reduced by heating it to increase its resistance value. In this way, the two-element demagnetizing element can significantly reduce the residual current by using the second positive temperature coefficient thermistor 2 (F:), and can reduce the flickering and blurring of colors on the CRT of color televisions. However, the conventional configuration of this two-element demagnetizing element has the following problems.

As shown in FIG. 1, in the conventional configuration, two spring terminals 5 and 6 are used to hold the first positive temperature coefficient thermistor 1 and the second positive coefficient thermistor 2. The two-element demagnetizing element needs to be thermally coupled and held as described above. Therefore, it is necessary to increase the strength of the spring terminals 5 and 6 so that they are firmly attached to each other. However, the second positive temperature coefficient thermistor 2 is used by making the temperature higher than that of the first temperature and generating heat to a high temperature. As a result, the spring terminals 5 and 6 may deteriorate due to heat, and similarly, the resin case 7 may undergo dimensional changes due to creep.
, 6 will become weaker and the force to press them will become weaker. As a result, the thermal coupling between the two positive temperature coefficient thermistors 1.2 becomes weak, and the second positive temperature coefficient thermistor 2 cannot fully exhibit its effects, resulting in an increase in residual current. Furthermore, the contact between the terminal plates 4 to 6 and the positive temperature coefficient thermistor 1.2 deteriorates, resulting in point contact and arc discharge occurs there when current flows.
This sometimes led to the destruction of the device.

As an example of configuring a two-element demagnetizing element using the conventional technology without using the spring terminals 5 and 6,
There is also a method of configuring two positive temperature coefficient thermistors and an intermediate terminal board by soldering, but in this case, there is a large difference in thermal expansion coefficient between the metal solder and the positive temperature coefficient thermistor, so that the thermal coupling is sufficiently good. Therefore, if solder is used to bond the entire electrode surface of a positive temperature coefficient thermistor, the element will be destroyed and destroyed during actual use.

Purpose of the Invention The present invention solves these conventional problems, and makes it possible to maintain the thermal coupling and contact state of two positive temperature coefficient thermistors forever.
The present invention provides a two-element demagnetizing element with high reliability and low residual current.

Structure of the Invention In order to achieve the above object, the two-element demagnetizing element of the present invention includes a first positive temperature coefficient thermistor having minute irregularities on the electrode surface, and a key, a first positive temperature coefficient thermistor on the electrode surface having a higher temperature. A metal common terminal plate is fixed to one electrode surface of each of the second PTC thermistors provided with minute irregularities using only an insulating adhesive, and this common terminal plate and each PTC thermistor are brought into contact. The minute protrusions on the electrode surface are brought into a conductive state, and the first terminal or lead wire and the second terminal or lead wire are fixed to the surface in contact with the common terminal plate and the other electrode surface, respectively. With this configuration, sufficient thermal coupling between the two positive temperature coefficient thermistors can be achieved, and the reliability can be improved.

Description of examples The configuration of the present invention will be explained below using one embodiment.

In Fig. 3, an electrode 13 whose surface is sprayed with aluminum, etc.
The first positive temperature coefficient thermistor 1o provided with the electrode 14 similarly to the first positive coefficient thermistor 10 provided with
A common terminal board 16, such as a copper plate, is sandwiched between the second positive temperature coefficient thermistor 11, which has a high temperature, and each electrode surface, and these are bonded together using a heat-resistant insulating adhesive such as silicone under pressure. be. j2. IEJj The electrode is made by spraying copper on top of the aluminum sprayed electrode to make it easier to solder.A first lead wire 17 and a second lead wire 1 are attached to each electrode surface.
8 is fixed to a part of the electrode surface with a small piece of solder 20. Figure 4 shows the common terminal board 16 using only insulating adhesive.
FIG. 2 is an enlarged cross-sectional view showing the positive temperature coefficient thermistors 10 and 11 fixed. The insulating adhesive 21 is a positive temperature coefficient thermistor 10.11
The terminal plate 16 and the electrode surface 13.14 are bonded to each other by entering into the four minute portions 22VrC of the electrode surface 13.14. The minute convex portion 23 is in direct contact with the terminal plate 16, and thermal coupling and electrical continuity are maintained at the same time.

The operation in the above configuration will be explained. A series circuit of an AC power source and a degaussing coil is connected between the common terminal plate 16 and the lead wire 17, and the same power source is connected to the common terminal plate 16 and the lead wire 18, and when the power is turned on, at first Since both the first positive temperature coefficient thermistor 10 and the second positive temperature coefficient thermistor 11 have low resistance, a large current flows through them, and the current gradually generates heat, and when the temperature of each reaches more than one temperature, the resistance suddenly decreases. rises and the current attenuates. At the same time, a large current initially flows through the degaussing coil and the current gradually attenuates. As a result of this action, a large alternating magnetic field is applied to the color TV cathode ray tube, and then a gradually smaller alternating magnetic field is applied to the color television tube, and the magnetized magnetic field is erased. The second positive temperature coefficient thermistor 11 has a higher point υ than the first positive coefficient thermistor 10, so its temperature is higher when thermal equilibrium is reached. Both positive characteristic thermistors 1
0°11 is fixed while being pressurized with the common terminal plate 16 in between, so the thermal coupling is sufficiently dense over the entire surface, so the heat of the second PTC thermistor 11 causes the first The positive temperature coefficient thermistor 10 is heated, and the balanced resistance value of the first positive coefficient thermistor 10 becomes large9, and the current flowing through the degaussing coil becomes extremely small, reducing color blur and flickering on the cathode ray tube. .

In the present invention, the first positive temperature coefficient thermistor 10 and the second positive coefficient thermistor 11 are bonded together using only the insulating adhesive 21 while applying pressure on the entire surface. Although the insulating adhesive 21 is bonded to the terminal board 16 and the positive temperature coefficient thermistors 10 and 11,
It absorbs the difference in thermal expansion coefficient between the
There is little deterioration of the contact part, and in addition, the positive temperature coefficient thermistor 10
．． Even if the surface of the element 11 has some irregularities, the insulating adhesive 21 will penetrate into the four parts, and the thermal bonding will be sufficient even if the element is not flat. Furthermore, if necessary, the function can be fully demonstrated even if the insulating case is omitted.

FIG. 5 shows yet another embodiment in which a first positive temperature coefficient thermistor 24 having electrodes on both sides and a second positive coefficient thermistor 25 having a key length of 1 m are connected to a common terminal plate 26.
The lead wire 2 is fixed on the same plane with pressure applied only with an insulating adhesive, and the lead wire 2 is fixed on the other surface similarly to the embodiment shown in FIG.
7.28 is fixed with solder. In this embodiment, the two PTC thermistors 24, 25 can be arranged in a straight line, and the overall shape can be made thin.

In each of the above embodiments, the case is omitted, but if necessary, it may be housed in the case.
The method for taking out the lead wires on the surface other than the thermal coupling surface of both positive temperature coefficient thermistors can be any conventional method, such as soldering,
Any method such as crimping may be used.

Effects of the Invention As is clear from the above embodiments, the two-element demagnetizing element of the present invention has two positive temperature coefficient thermistors bonded together over the entire surface through a common terminal plate using only an insulating adhesive, thereby achieving thermal coupling. Since it can be realized with a simple configuration and does not deteriorate, it is possible to provide a highly reliable two-element demagnetizing element with low residual current at a low cost.

[Brief explanation of the drawing]

Figure 1 is a cross-sectional view showing a conventional two-element demagnetizing element, and Figure 2 (
3 is a circuit diagram explaining the operation of the two-element demagnetizing element, FIG. 3 is a sectional view showing an embodiment of the two-element demagnetizing element of the present invention, and FIG.
The figure is an enlarged sectional view of the same essential part, and FIG. 5 is a perspective view of another embodiment. 10.24 ・First positive temperature coefficient thermistor, 11°25
- second positive temperature coefficient thermistor, 12,13°14.15
Electrode, 16. 26 - Common terminal plate, 21. Insulating adhesive, 22. Microscopic recess, 23... Microscopic projection. Name of agent: Patent attorney Toshio Nakao and 1 other person No. 1
figure

Claims (1)

[Claims] On one electrode surface of each of a first positive temperature coefficient thermistor having minute irregularities between the electrodes and a second positive temperature coefficient thermistor having minute irregularities on the electrode surface having a temperature higher than that of the first positive temperature coefficient thermistor. A metal common terminal plate is fixed with only insulating adhesive, and the minute protrusions on the electrode surfaces where this common terminal plate and each positive temperature coefficient thermistor are in contact are in a conductive state, and the surfaces that are in contact with the common terminal plate are A two-element demagnetizing element in which a first terminal or lead wire and a second terminal trench or lead wire are respectively fixed to separate electrode surfaces.