JPH0289253A - Method for adjusting output timing of motor rotation reference position signal - Google Patents

Abstract

PURPOSE:To simply adjust the output timing of a signal without complexing constitution by forming a magnetic force adjusting means for generating the magnetic force of a magnet in the increasing or decreasing direction of the magnetic force and changing a distance between the magnetic force adjusting means and the magnet. CONSTITUTION:When the magnetic force adjusting means 16 is approached to the magnet 13 fixed on a rotor 6, the magnetic force of the magnet 13 is increased or decreased in accordance with the magnetic force direction of the means 16 and the distance between the magnet 13 and the means 16. When the magnet 13 whose magnetic force is increased or decreased is opposed to a magnetic sensor 14 following the rotation of the rotor 6, the signal level of a voltage signal outputted from the sensor 14 is changed and the output timing of a pulse signal outputted from pulse generating circuit is also changed. Thereby, the output timing of the pulse signal can be allowed to coincide with the rotation reference position of the rotor 6 by changing the magnetic force of the magnet 13 by the means 16. Consequently, the output timing can be simply adjusted without complexing the constitution.

Description

[Detailed Description of the Invention] [Purpose of the Invention] (Industrial Application Field) The present invention adjusts the output timing of a pulse signal that is output to indicate the rotational reference position of the rotor according to the rotation of the rotor. The present invention relates to a method for adjusting the output timing of a rotation reference position signal of a motor.

(Prior Art) For example, in a brushless morph for driving a 3.5-inch floppy disk, the index point of the 3.5-inch floppy disk is mounted in a fixed position on the rotor. - is detected indirectly on the rotor side (R configuration).

In other words, a 3.5-inch type floppy disk does not have a 1" mark that directly indicates the index point of the floppy disk, like the index hole provided on a 5-inch or 8-inch type floppy disk. From this rotor rotation 7! to the rotor side where the floppy disk is mounted in a positioned state!
A device for indicating a quasi-position is provided, and the index point of the floppy disk is indirectly determined by detecting the reference rotational position of the rotor using the device.

As an example of such a device, a magnet for detecting a rotation reference position is provided at a specific position of the rotor, and a magnetic sensor is provided to face the rotation locus of the magnet, and an output is output from the magnetic sensor in response to the approach of the magnet. The configuration is such that an index pulse signal (rotation reference position signal) is output from a pulse generation circuit based on a voltage signal. Therefore, by detecting the output timing of the index pulse signal output from the pulse generation circuit, the index point of the floppy disk can be indirectly determined.

By the way, the magnetic sensor is positioned so that the index pulse signal is output from the pulse generating circuit exactly at the timing when the floppy disk rotates to the index point, that is, the rotor reaches the rotation reference position.

However, depending on the characteristics of individual parts or assembly accuracy, the timing at which the rotor reaches the rotational reference position and the timing at which the index pulse signal is output from the pulse generation circuit often do not match. If the timings of the two do not match, it will be difficult to write or read data on the floppy disk, so the conventional method of matching the timing of both is to move and adjust the position of the magnetic sensor. There is. That is, by moving the magnetic sensor along the movement locus of the magnet, the output timing of the index pulse signal from the pulse generation circuit is adjusted, thereby making the timings of the two coincident.

(Problem to be Solved by the Invention) However, in the conventional adjustment method described above, the magnetic sensor must be provided so that it can be moved finely, which complicates the configuration and requires work to finely move the magnetic sensor. It has the disadvantage of being troublesome.

SUMMARY OF THE INVENTION Therefore, an object of the present invention is to provide a method for adjusting the output timing of a motor rotation reference position signal that can easily adjust the output timing of a pulse signal indicating the rotor rotation reference position without complicating the configuration. Proposition 1j is as follows.

[Structure of the Invention] (Means for Solving the Problems) A JNN right method for output timing of a position signal to a rotation base of a motor according to the present invention, a magnet for detecting a co-rotation reference position provided at a specific position of a rotor, A magnetic sensor is provided to face the rotation locus of the magnet in the χ·I direction and generates a voltage signal in response to a change in magnetic force from the magnet, and the rotor rotates based on the voltage signal from the magnetic sensor. In a motor equipped with a pulse generation circuit that generates a pulse signal indicating a position, a magnetic force adjusting means for generating a magnetic force in a direction to increase or demagnetize the magnetic force of the magnet is provided, and a distance between the magnetic force adjusting means and the magnet is provided. The output timing of the pulse signal from the pulse generating circuit is adjusted by changing .

(Function) When the rotor rotates and the rotation reference position magnet provided on the rotor faces the magnetic sensor, a voltage signal is output from the magnetic sensor. Then, the pulse generation circuit outputs a pulse signal indicating the rotational reference position of the rotor based on the voltage signal, so that the rotational reference position of the rotor can be detected based on the output timing of this pulse signal.

Now, when the output timing of pulse No. 1M from the pulse generation circuit is out of order, the output timing is adjusted as follows. That is, when the magnetic force adjustment means is brought close to the magnets provided on the rotor, the direction of the magnetic force of the magnetic force adjustment means and the magnetic force between the magnets, 2! The magnetic force of the magnet is increased or decreased depending on the distance from the adjusting means. When the magnet, which has been magnetized or demagnetized, faces the magnetic sensor as the rotor rotates, the signal level of the voltage signal output from the magnetic sensor changes, and accordingly, the pulse signal output from the pulse generation circuit changes. The output timing will also change. Therefore, by changing the magnetic force of the magnet using the magnetic force adjusting means, the output timing of the pulse signal can be made to match the rotation reference position of the rotor.

(Embodiment) Hereinafter, an embodiment in which the present invention is applied to an axial gap type brushless smoke for driving a floppy disk will be described with reference to the drawings.

In FIGS. 1 and 2, 1 is a stator, which is constructed as follows. That is, 2 is a board which also serves as a stator yoke, and a bearing housing 4 having bearings 3, 3 is installed in a mounting hole 2a formed in the center of this board by 1%-7ff. Reference numeral 5 denotes a plurality of armature coils fixed on the substrate 2, and these are arranged in a ring shape with the bearing housing 4 as the center.

On the other hand, 6 is a rotor, which is constructed as follows. That is, 7 is a rotary shaft inserted and supported by the bearings 3, 3, 8 is a shallow container-shaped rotor yoke attached to the upper end of the rotary shaft 7, and the field magnet 9 is attached to the inner bottom surface of the rotor yoke. It is accompanied by the armature coil 5 in a facing state. Reference numeral 10 denotes a frequency power generation magnet fixed inside the outer circumferential wall of the rotor yoke 8, and a frequency power generation coil portion (not shown) is formed on the substrate 2 to face the frequency power generation magnet 10.

Further, reference numeral 11 denotes a disk mounting section fixed to the upper end of the rotating shaft 7, into which a 3.5-inch type floppy disk (not shown) is mounted. and,
An engagement pin 12 is provided upright in the disk loading section 11, and when a floppy disk is installed in the disk loading section 11, the pin 12 engages with the engagement hole of the floppy disk and the floppy disk is inserted into the disk loading section 11. The disk is mounted on the rotor 6 in a positioned manner.

Reference numeral 13 indicates a magnet for detecting rotation back position fixed at a predetermined position on the outside of the outer circumferential wall of the rotor yoke 8; .

) coil, which outputs an alternating voltage signal as the magnet 13 rotates. Various electronic components are mounted on the substrate 2 at positions around the outer periphery of the rotor yoke 8.

FIG. 3 shows a block diagram of the electrical configuration.

15 is a pulse generation circuit connected to the PG coil 14;
This outputs an index pulse signal based on the alternating voltage signal given from the PG coil 14.

Now, according to the above configuration, when the rotor 6 rotates in response to energization of the armature coil 5, the magnets 13 periodically oppose the PG coil 14. Then, an alternating voltage signal is generated in the PC coil 14 as the magnet 13 approaches. The signal level of this alternating voltage signal is proportional to the degree of reduction in the magnetic flux density applied to the PG coil 14, and when the magnet 13 approaches the PG coil 14, the signal level is, for example, H level, When it moves away from it, it becomes a positive level. As a result, the voltage signal output from the PG coil 14 becomes an alternating voltage signal centered around the zero level, as shown by the solid line in FIG. 5(a).

The alternating voltage signal from the PC coil 14 is output to a pulse generating circuit 15, and an index pulse signal is generated in this pulse generating circuit 15. In other words, when the alternating voltage signal from the magnetic sensor 14 reaches the negative lower limit setting level when the alternating voltage signal is rising, the signal level of the index pulse signal is raised, and when the alternating voltage signal is falling, the positive upper limit setting level is set. When the level is reached, the signal level of the index pulse signal is lowered. Therefore, in response to the rotational movement of the magnet 13 as the rotor 6 rotates, the index pulse signal is output from the pulse generation circuit 15. Since this index pulse signal indicates that the floppy disk loaded into the disk loading section 11 is located at the index point, the output timing of the index pulse signal is determined so that the floppy disk is located at the index point. It must match the timing. In other words,
Writing data to or reading data from a floppy disk is performed based on the output timing of the index pulse signal, so if the output timing of the index pulse signal differs depending on the disk device, it may be difficult to accurately write data to the floppy disk. This is because there is a possibility that writing or reading may not be possible.

Therefore, when the output timing of the index pulse signal and the timing at which the floppy disk is positioned at the index point do not match, the adjustment is made as follows. First, a 365-inch type Jy4 floppy disk is loaded into the disk loading section 11. Data for generating a burst signal is stored in a predetermined position on this adjustment floppy disk, and as the floppy disk rotates, an adjustment burst signal is output as shown in FIG. 5(d). . Here, the predetermined position where the burst signal generation data is stored is set to a position where the adjustment burst signal is output, for example, 400 μsees after the floppy disk rotates and the floppy disk is located at the index point.

Now, when the above-mentioned # adjustment floppy disk is installed in the disk mounting section 11 and the data is read, an index pulse is generated from the pulse generation circuit 15 as shown in FIG. 5(b) as the adjustment floppy disk rotates. signal(
An output time width of 3.5m5ec) is output, and a predetermined time (3.5m5ec) is output from the output timing of the index pulse signal.
After a lapse of time (hereinafter referred to as i'1llJ fixed time), a 1!1 Seikawa bust signal is output. At this time, if the measurement time width deviates by more than 400 μsec, a magnetic force adjusting magnet 16 is attached to the magnet 13 provided on the rotor 6 as a magnetic force adjusting means for controlling a magnetic force stronger than the magnetic force of the magnet 13 provided in the rotor 6. The magnetic force of the magnet 13 is adjusted by approaching it from the front as shown in FIG. In other words, in general, when a magnet is given a magnetic force larger than its own magnetic force in the same polar direction, it will generate a larger magnetic force than the previous magnetic force, and
When a magnetic force larger than its own magnetic force is applied in the opposite polarity direction, it has the property of generating a smaller magnetic force than the previous magnetic force. By bringing the adjustment magnets 16 close together so that their magnetic forces are in the same direction or in opposite directions,
The magnetic force of the magnet 13 is increased or decreased. This changes the magnetic force applied from the magnet 13 to the PC coil 14, thereby making it possible to adjust the output timing of the index pulse signal.

Specifically, as shown in FIGS. 5(b) and 5(d), for example, the measurement time width ts (fifth
(see FIG. 4(d)) is shorter than, for example, 100 μSee, the magnetic force adjustment magnet 16 is brought close to the magnet 13 so that its magnetic force is in the opposite direction, as shown in FIG. 4(b). Then, the magnetic force of the magnet 13 is demagnetized compared to the previous magnetic force, and the magnetic force applied to the PC coil 14 decreases accordingly, so that the signal level of the alternating voltage signal output from the PC coil 14 becomes as shown in FIG. As shown by the broken line in (a), the overall level is lowered. As a result, the timing at which the alternating voltage signal exceeds the lower limit setting level in the rising state advances, and the output timing of the index pulse signal advances. Therefore, the lung 1 constant time width tl is, for example, 400 μ
By bringing the magnetic force adjustment magnet close to the magnet 13 until the magnetic force is within the range of ±300 p scC (±300 μsec is an allowable range), the output timing of the index pulse signal of the disk device can be adjusted to the regular timing. can.

Also, h! When the constant time width t1 is longer than 700 μSee, the magnetic force adjustment magnet 16 is brought close to the magnet 13 so that the magnetic forces are in the same direction as shown in FIG. 4(a). Then, since the magnetic force of the magnet 13 is increased more than the previous magnetic force, the signal level of the alternating voltage signal from the PG coil 14 increases as a whole, and the output timing of the index pulse signal is delayed accordingly. become. Therefore, the measurement time t1 is 400 B sec±3001t s
By bringing the magnetic force adjustment magnet 16 close to the magnet 13 until the range of ee is reached, the output timing of the index pulse signal of the disk device can be adjusted to the regular timing.

In short, in the case of the above embodiment, the output timing of the index pulse signal is adjusted by bringing the magnetic force adjustment magnet 16 close to the magnet 13 provided on the rotor 6, so the position of the magnetic sensor is adjusted by moving. Unlike the conventional method of adjusting the output timing of the index pulse signal, this eliminates the need for a structure for moving the PG coil 14, thereby preventing the overall configuration from becoming cluttered. The output timing of the pulse signal can be adjusted.

The effect of increasing and demagnetizing the magnet 13 by the magnetic force adjusting magnet 16 increases as the magnetic force adjusting magnet 16 approaches the magnet 13, and also increases as the magnetic force of the magnetic force adjusting magnet 16 increases. Therefore, as a method for increasing or demagnetizing the magnetic force of the magnet 13, in addition to changing the distance between the two when the magnetic force adjustment magnet 16 is brought close to the magnet 13 as in the above embodiment, Magnetism! ! A plurality of Jl magnets may be prepared, and a magnetic force adjustment magnet may be appropriately selected according to the measurement time width t1 so as to be always brought close to the magnet 13 at a constant distance.

In this case, it can be expected that magnetization or demagnetization of the magnet 13 can be performed stably without excess or deficiency.

Further, in the above embodiment, the magnet 13 is used as the magnetic force 1 adjusting means.
Although the magnetic force adjusting magnet 16 having a larger magnetic force is used, instead of this, an electromagnet that exerts a larger magnetic force than the magnetic force of the magnet 13 may be used. Furthermore, the direction of current and the current applied to the electromagnet may be controlled in accordance with the measurement time width t1, or such control may be performed automatically. In addition, a Hall element may be used as the magnetic sensor.

In addition, the present invention is not limited to what is shown in the above-mentioned drawings, but can be applied to various motors, and can be implemented with various modifications within the scope of the invention.

[Effects of the Invention] As is clear from the above description, the method for adjusting the output timing of a motor rotation reference position signal according to the present invention includes a magnetic force adjusting means that generates a magnetic force in a direction to increase or demagnetize the magnetic force of a magnet. Since the output timing of the pulse signal from the pulse generation circuit is adjusted by changing the distance between the magnetic force adjusting means and the magnet, the output timing of the pulse signal indicating the rotational reference position of the rotor can be adjusted as follows.
It has excellent practical effects in that it can be easily adjusted without complicating the configuration.

[Brief explanation of the drawing]

The drawings show one embodiment of the present invention; Fig. 1 is an overall plan view, Fig. 2 is an overall front view, Fig. 3 is a block diagram showing the electrical configuration, and Fig. 4 is an increase/decrease in the number of magnets. FIG. 5, which is a diagram for explaining the magnetic effect, is a signal waveform diagram for comparing the output timing of each signal. In the figure, 1 is a stator, 6 is a rotor, 13 is a magnet, 14 is a P, G coil (magnetic sensor), 15 is a pulse generation circuit,
16 is a magnetic force adjustment magnet (magnetic force adjustment means). Figure 1 Applicant: Toshiba Corporation Toshiba Audio/Video Engineering Co., Ltd. Figure 2 Figure (a) (b)

Claims (1)

[Claims] 1. A magnet for detecting a rotation reference position provided at a specific position of the rotor, a magnetic sensor provided to face the rotation locus of this magnet and generating a voltage signal according to changes in magnetic force from the magnet, and this A magnetic force that generates a magnetic force in a direction to increase or demagnetize the magnetic force of the magnet, in a motor equipped with a pulse generation circuit that generates a pulse signal indicating a reference rotation position of the rotor based on a voltage signal from a magnetic sensor. Output of a rotation reference position signal of a motor, characterized in that an adjustment means is provided, and the output timing of the pulse signal from the pulse generation circuit is adjusted by changing the distance between the magnetic force adjustment means and the magnet. How to adjust timing.