JPH0454670Y2 - - Google Patents

Description

[Detailed Description of the Invention] [Field of Industrial Application] This invention relates to an inspection device for a static convergence adjustment magnet for inspecting the position and polarity of each magnetic pole of a static convergence adjustment magnet for a color cathode ray tube.

[Conventional technology]

In general, a magnet for static convergence adjustment for color cathode ray tubes is constructed as shown in Fig. 3, in which 1, 2, and 3 are annular hexapoles, respectively; 4
This is a magnet body for poles and two poles, and the magnet body 1 for six poles has N, S, N, S, N, S at equal intervals.
Two plastic magnet plates 1a and 1b each having six magnetic poles are bonded together so that the different magnetic poles overlap each other, and in the same way, the four-pole magnet body 2 is formed at equal intervals. N, S,
Two plastic magnet plates 2a and 2b having four magnetic poles, N and S, are bonded together so that the different magnetic poles overlap each other, and the two-pole magnet body 3 is made of N at equal intervals,
Two plastic magnet plates 3a and 3b having S2 magnetic poles are bonded together.

In addition, N and S in Fig. 3 indicate magnetic poles,
When viewed in plan, the 6-pole magnet element 1 has a central angle of 60°, the 4-pole magnet 2 has a central angle of 90°, and the 2-pole magnet 3 has a central angle of 90°. Each magnetic pole is arranged every 180°.

4, each magnet element body 1, 2, 3 is a spacer 5
It is a magnet that is rotatably joined through
Each magnet body 1
~3 are joined.

When inspecting the position and polarity of each magnetic pole of such a magnet 4, for example, in the same way as when inspecting the position and polarity of a magnetic pole of a stator of a pulse motor, etc., each magnetic pole of each magnet body 1 to 3 is inspected. Magnetic detectors are arranged close to each other at corresponding positions, and each detector inspects the number of magnetic poles, the position of each magnetic pole, the polarity of each magnetic pole, etc. for each magnet body 1 to 3.

[Problem that the invention attempts to solve]

However, in this case, a number of magnetic detectors corresponding to the number of magnetic poles of each magnet body 1 to 3 are required, and a very large number of magnetic detectors are required. The signal processing circuit to be processed becomes complicated, the inspection equipment becomes very expensive and has a complex configuration, and the spacing between each magnet element 1 to 3 is narrow, making it impossible to arrange all the magnetic detectors. First, there is a problem in that measurement must be performed for each magnet body 1 to 3, which is extremely time consuming.

In addition, as a magnetic sensor, for example,
56700, each of which is applied to a variety of uses, and the one described in the above publication is suitable for detecting the rotation of a car crankshaft, etc., but the color cathode ray as mentioned above Even when applied to the inspection of pipe integrity magnets, the above-mentioned problems cannot be solved.

Therefore, this invention makes it possible to inspect the position and polarity of each magnetic pole by simply examining two magnetic poles, even if the number of magnetic poles in each magnet element of the static convergence adjustment magnet to be inspected is large. This is a technical issue.

[Means for solving problems]

This invention was made with the above points in mind, and is a static convergence adjustment magnet for color cathode ray tubes in which a plurality of annular magnet bodies each have a plurality of magnetic poles with different numbers of magnetic poles. In a static convergence adjustment magnet inspection device for inspecting the position and polarity of each magnetic pole of the magnet, each of which is formed by bonding each of the magnet elements, a plurality of magnetoresistive elements are bridge-connected. a plurality of magnetic sensors dedicated to each of the magnet bodies, which are formed and integrated in close proximity to each of the magnet bodies, and a power source that supplies a constant current to each of the magnetic sensors, respectively;
The present invention is an inspection device for a static convergence adjustment magnet, which includes a detection display section that is provided between both output terminals of each of the magnetic sensors and detects and displays the potential difference between the output terminals.

[Effect]

Therefore, according to this invention, a plurality of magnetoresistive elements are bridge-connected and a magnetic sensor dedicated to each of the plurality of magnet bodies formed integrally is disposed close to each magnet body. By adjusting each magnetic sensor so that the potential difference between the output terminals of each magnetic sensor is zero in a standard state where there is no positional shift or polarity reversal of each magnetic pole of each magnet element, each magnetic sensor can be connected to each magnet. By simply placing it close to the element, the position and polarity of the magnetic poles of each magnet element can be inspected simultaneously, eliminating the need for a large number of magnetic detectors as in the past.
With a device having a simple configuration, it is possible to easily determine whether a magnet for static convergence adjustment is good or bad.

〔Example〕

Next, this invention will be explained in detail with reference to FIGS. 1 and 2 showing one embodiment thereof.

In FIG. 1, 6, 7, and 8 are the 6 above, respectively.
These are first to third magnetic sensors dedicated to magnetic bodies 1, 2, and 3 for poles, 4 poles, and 2 poles, and each magnetic sensor 6 to 8 has four magnetoresistive elements 6a.
~6d, 7a~7d, and 8a~8d are bridge-connected, and the positive,
Both ends of a first power supply 9 for constant current supply are connected to the connection point of the magnetoresistive elements 6a, 6c, which are negative power supply terminals, and the connection point of the magnetoresistive elements 6b, 6d, and the second
The connection point between the magnetoresistive elements 7a and 7c, which are the positive and negative power supply terminals of the magnetic sensor 7, and the magnetoresistive element 7
A second power supply 10 for constant current supply is connected to the connection point of b and 7d.
A connection point between the magnetoresistive elements 8a and 8c, which are the positive and negative power supply terminals of the third magnetic sensor 8,
Both ends of a third power supply 11 for constant current supply are connected to the connection point between the magnetoresistive elements 8b and 8d.

Then, the magnetoresistive element 6 of each magnetic sensor 6 to 8
a and 6b, 6c and 6d, 7a and 7b, 7c and 7
d, 8a and 8b, and 8c and 8d are movable as a pair, and each of the magnetoresistive elements 6a and 6b, 6c and 6d, 7a and 7b, 7c and 7
d, 8a and 8b, and 8c and 8d, respectively, for example, as magnetic sensor elements A, B, C, D,
E and F, sensor elements A and B are held by a holder (not shown) at both ends of a fan arc with a center angle of 60° with the positive power terminal side facing upward; C and D are held at both ends of a fan arc with a center angle of 90° with the positive power terminal side facing upward, and the sensor elements E and F are held at both ends of the semicircular arc by the holder. The holder is held with the power terminal side facing up, and the magnetic sensors 6 to 8 are integrated with the holder, and the holder is attached to the inside of the safety magnet 4 to be inspected for inspection.

Moreover, the magnetoresistive element 6 of each magnetic sensor 6 to 8
For example, the resistance value of a, 6d, 7a, 7d, 8a, and 8d increases when it comes close to the N or S pole of the magnet, and the resistance value of the magnetoresistive elements 6b, 6c, 7b, 7
C, 8b, and 8c are wired such that the resistance value increases when the magnet approaches the S or N pole of the magnet.

12, 13, and 14 have one end connected to each magnetic sensor 6 to 8.
The first to third current-limiting resistors 15, 16, and 17 connected to the negative power terminal of are the first to third amplifiers, and both input terminals of the first amplifier 15 are connected to both outputs of the first magnetic sensor 6. Magnetoresistive element 6a which is a terminal,
The input terminals of the second amplifier 16 are connected to the connection point of magnetoresistive elements 7a and 7b, which are both output terminals of the second magnetic sensor 7, and the connection point of magnetoresistive elements 7a and 7b, which are both output terminals of the second magnetic sensor 7. Resistance element 7
c and 7d, both input terminals of the third amplifier 17 are both output terminals of the third magnetic sensor 8, which are the connection point of the magnetoresistive elements 8a and 8b and the connection point of the magnetoresistive elements 8c and 8d. It is connected to the.

18, 19, and 20 have each amplifier 1 on both ends.
The sliding piece is connected to both input terminals 5 to 17 and has a resistance of 1.
4th to 6th resistors for balance adjustment consisting of variable resistors connected to the other ends of 2 to 14, respectively;
1, 22, and 23 are seventh to ninth resistors for meter sensitivity adjustment, each consisting of a variable resistor whose one end is connected to the output terminal of each amplifier 15 to 17 and the other end is grounded; 24, 25, and 26 are input terminals. are connected to the sliding pieces of the resistors 21 to 23.
meter, each resistor 12-14 and 18-2
3. The amplifiers 15 to 17 and the meters 24 to 26 constitute first to third detection display units 27, 28, and 29 that detect and display the potential difference between the output terminals of the magnetic sensors 6 to 8, respectively. There is.

In addition, 30 is a judgment display section, and each meter 24
When the deflection of any one of the needles from 26 to 26 exceeds the allowable range, it is indicated that the magnet 4 is defective.

Next, the operation of the embodiment will be explained.

Now, to explain the case where the position of the magnetic pole of the six-pole magnet body 1 is inspected by the first magnetic sensor 6, as shown in FIG. 2a, when the six-pole magnet body 1 is viewed from above, Assuming a position ~ where the central angle θ is resolved every 30°, move clockwise from the reference position as shown in figure a.
After rotating by 30 degrees, the north pole is located, and after that, rotated by 60 degrees, ,,,, respectively, S, N, S,
When the N and S poles are located, the sensor elements A and B of the first magnetic sensor 6 are respectively arranged inside the magnet body 1 at the above positions, for example.

FIG. 2b shows the above-mentioned state as a developed view when viewed from inside the magnet body 1.
At this time, as shown in FIG. 2a, a standard magnet element body similar to the six-pole magnet element body 1 having six magnetic poles at equal intervals is prepared,
With respect to this standard magnet body, sensor elements A and B of the first magnetic sensor 1 are placed at the positions shown in FIG. 18 to balance the sensor 6, and when the sensor elements A and B of the first magnetic sensor 6 are placed at positions , relative to the six-pole magnet body 1 to be inspected, the magnet Magnetic plates 1 above and below element body 1
If the upper and lower magnetic poles are misaligned due to misalignment when adhering a and 1b, the balance of magnetic flux reaching the sensor elements A and B will be disrupted due to the misalignment of the magnetic poles, and the balance of the magnetic sensor 6 will be disrupted, causing each The resistance values of the magnetic resistance elements 6a to 6d change, and a potential difference is generated between the output terminals of the magnetic sensor 6. This potential difference is amplified by the first amplifier 15, causing the needle of the meter 24 to move, indicating that the magnet body 1 is defective. I understand that there is something.

Furthermore, even if the polarity of each magnetic pole of the magnet element 1 is opposite to that of the standard magnet element described above, the degree of change in the resistance value of the magnetic sensor 6 is different from that at equilibrium, so that the magnetic A potential difference occurs between the output terminals of the sensor 6, and the needle of the meter 24 moves, indicating that the six-pole magnet element 1 to be inspected is defective.

Furthermore, the positions and polarities of the magnetic poles of the 4-pole magnet element 2 and the 2-pole magnet element 3 are inspected in the same manner as in the case of the 6-pole magnet element 1, and the meters 25 and 26 are inspected. It is possible to judge whether the product is good or bad based on the movement of the needle.

At this time, in the normal state, the magnetic poles of the four-pole magnet body 2 are as shown in FIG.
The magnetic poles of the two-pole magnet body 3 are located at four locations: between , between , and between .
Because they are located at the two locations shown in Figures a and b, when the holder holding each sensor element A to F is attached to the inside of the magnet 4, the holder is attached to each of these magnet bodies 1 to 3. By providing the holder with a positioning mechanism so that the holder is always mounted in the same positional relationship, each magnet body 1 to
3. Good and bad inspections can be performed at the same time.
Based on the display on the judgment display section 30, the magnet 4
This makes it easy to distinguish between good and bad products.

[Effect of idea]

As described above, according to the static convergence adjustment magnet inspection device of this invention, even if the number of magnetic poles in each magnet element of the static convergence adjustment magnet is large, the magnetic sensor with the bridge-connected magnetoresistive elements can The position and polarity of the magnetic poles on the magnet body can be inspected by simply checking each magnetic pole at each location, eliminating the need for a number of magnetic detectors corresponding to the number of magnetic poles on the magnet body as in the past. In addition, the position and polarity of each magnetic pole can be inspected simultaneously for multiple magnet bodies using dedicated magnetic sensors, and the simple configuration improves the quality of static convergence adjustment magnets such as power magnets. ．． Defects can be easily inspected.

[Brief explanation of the drawing]

1 and 2 show an embodiment of the static convergence adjustment magnet inspection device of this invention, FIG. 1 is a wiring diagram, FIG. 2a is a plan view of a part during inspection, and FIG. b is a developed view of figure a, figure 3 a,
FIG. 1B is a plan view and a front view of a power magnet, which is a general static convergence adjustment magnet. 1, 2, 3... Magnet element body, 4... Pilly magnet, 6, 7, 8... Magnetic sensor, 6
a to 6d, 7a to 7d, 8a to 8d... Magnetoresistive element, 9, 10, 11... Power supply, 27 to 29...
Detection display section.

Claims (1)

[Scope of utility model registration request] A plurality of annular magnet bodies each have a plurality of magnetic poles having different numbers of magnetic poles, and a static convergence adjustment magnet for a color cathode ray tube is formed by joining each of the magnet bodies, and each magnetic pole of the magnet In a static convergence adjustment magnet inspection device that inspects the position and polarity of
a plurality of magnetic sensors dedicated to each of the magnet elements, each of which is formed by bridge-connecting a plurality of magnetoresistive elements, and which are arranged in close proximity to and integrated with each of the magnet elements; and a plurality of magnetic sensors dedicated to each of the magnet elements; Inspection of a magnet for static convergence adjustment, which is equipped with a power source that supplies a constant current to each of the magnetic sensors, and a detection display section that is provided between both output terminals of each of the magnetic sensors and detects and displays the potential difference between the output terminals. Device.