JPS61185840A - Deflection yoke inspection apparatus - Google Patents

Abstract

PURPOSE:To measure the characteristic of deflection yoke accurately and easily by providing a measuring yoke for catching the magnetic field produced by A.C. current flowing through the deflection coil and a device for measuring the currents flowing through the deflection coil and induced in the measuring coil. CONSTITUTION:Flux 13 is produced in the core 12 by A.C. current flowing through a deflection coil 8 to induce a voltage across a coil 9. While the current flowing through the deflection coil 8 will induce a voltage across a resistor 7. Since the voltage induced across the coil 9 is the differential of flux produced by the current flowing through the deflection coil 8, the output voltage of an integrator 10 has same shape with the flux produced by the deflection coil 8. Consequently, deflection current is inputted to X-axis of oscilloscope while the flux density of deflection field is inputted to Y-axis to describe a hysteresis curve. In such a manner, the magnetic field produced through the deflection yoke can be measured accurately.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to an inspection device for a deflection yoke used in a television receiver or the like.

2. Description of the Related Art Conventionally, the characteristics of a deflection yoke are tested by winding a coil 2 around a toroidal core 1 made of the same material as the core constituting the deflection yoke, as shown in Fig. 4, and using this as a test piece. The -H characteristics were measured as shown in FIG. Through this, we learned the characteristics of the core that makes up the deflection yoke and estimated the characteristics of the entire deflection yoke.

Further, as shown in FIG. 6, a test coil 4 was inserted into the core 3 to measure the characteristics of the core, and the characteristics of the deflection yoke were estimated.

Problems to be Solved by the Invention However, with the above method, the characteristics of the deflection yoke are estimated by measuring the characteristics of the core, so the exact characteristics of the deflection yoke cannot be determined.

The present invention has been made with attention to the above points, and an object thereof is to provide a deflection yoke inspection device that can accurately and easily measure the characteristics of a deflection yoke.

Means for Solving the Problems The present invention provides an AC power source that supplies an AC current to a deflection coil;
It is equipped with a measurement coil that picks up the magnetic field generated by the alternating current flowing through the deflection coil, and a measurement device that measures the current flowing through the deflection coil and the current generated in the measurement coil.

Since the present invention is comprised of the above-described means, it is possible to accurately measure the magnetic field generated by the deflection yoke, and in order to measure the characteristics of the completed deflection yoke, it is possible to inspect it during the manufacturing process of the deflection yoke. be able to.

EXAMPLES Hereinafter, examples of the present invention will be described in detail with reference to FIGS. 1 to 3.

In FIG. 1, 6 is a slider, and input terminal 6
is connected to a power outlet (not shown). Further, the output of the slider 6 is connected to a deflection coil 8 via a resistor 7.

A measurement coil 9 is connected to a Y-axis input terminal of an oscilloscope 11 via an integrator 10, and an X-axis terminal of the oscilloscope 11 is connected to a resistor 7.

In FIG. 2, reference numeral 12 denotes a core around which the deflection coil 8 is wound, and a magnetic flux 13 is generated inside the core 12 by the deflection coil 8.

FIG. 3 is a cross-sectional view taken along the line N in FIG. 2.

The present invention has the above-described configuration, and a magnetic flux 13 is generated inside the core 12 by the alternating current flowing through the deflection coil 8, and a voltage is generated in the measurement coil 9 due to this magnetic flux.

Furthermore, a voltage is generated across the resistor 7 due to the current flowing through the deflection coil 8 .

Since the voltage generated by the measuring coil 9 is a derivative of the magnetic flux created by the current flowing through the deflection coil 8, the output voltage of the integrator 10 has the same form as the magnetic flux created by the deflection coil 8.

Therefore, the deflection current is on the X axis of the oscilloscope 11.
The magnetic flux density of the deflection magnetic field is input to the Y axis. That is, a hysteresis curve is drawn on the oscilloscope 11 as shown in FIG. 4, with the deflection current as the X axis and the s flux density of the deflection magnetic field as the Y axis.

Here, 14 is a normal waveform, and what is indicated by a broken line 16 is a waveform of a defective deflection yoke.

According to this, it can be seen that sufficient magnetic flux is not generated because the magnetic flux is saturated due to a short circuit in the deflection coil 8 or a defective material of the core 12.

In other words, since the present invention measures the magnetic flux generated by the completed deflection yoke, it is possible to detect any defects in the deflection coil 8, the core 12, or the magnetic material added to adjust the s-flux. This allows the characteristics of the deflection yoke to be known accurately.

Furthermore, since the present invention is capable of inspecting a completed deflection yoke, the inspection apparatus of the present invention can be incorporated into a production line for deflection yokes.

Effects of the Invention The present invention provides an AC power source that supplies an AC current to a deflection coil;
It is equipped with a measuring coil that picks up the magnetic field generated by the alternating current flowing through the deflection coil, and a measuring device that measures the current flowing through the deflection coil and the current generated in the measuring coil, so it is possible to accurately measure the magnetic field generated by the deflection yoke. In order to measure the characteristics of the completed deflection yoke, it can be inspected during the manufacturing process of the deflection yoke.

[Brief explanation of the drawing]

Fig. 1 is a circuit diagram of a deflection yoke inspection device according to an embodiment of the present invention, Fig. 2 is a top view of the main parts of the same test equipment, Fig. 3 is a sectional view of the main parts, and Fig. 4 is a characteristic diagram of the same. , FIG. 6 is a plan view of the conventional example, FIG. 6 is a characteristic diagram thereof, and FIG. 7 is a perspective view thereof. 6...Slidac, 6...Input terminal, 7...Resistor, 8...Deflection Koinope9.
...Measurement coil, 10...Integrator, 11
...Oscilloscope, 12 ...Core, 1
3...Magnetic flux. Name of agent: Patent attorney Toshio Nakao and 1 other person No. 1
Figure 3, Figure 4, Figure 5. H

Claims (1)

[Claims] An AC power supply that supplies alternating current to the deflection coil and a measurement coil that picks up the magnetic field generated by the alternating current flowing through the deflection coil are provided, and the current flowing through the deflection coil and the current generated in the measurement coil are measured. An inspection device for a deflection yoke, characterized in that it is provided with a device that displays the relationship between the following.