JPS60121985A - Rotation controller of rotor - Google Patents

Abstract

PURPOSE:To suppress the irregular rotation due to the variation in the torque of a motor by reading out a torque variation correcting data from storing means in response to the rotating angle detection signal of a rotor and controlling the drive of a motor with this data. CONSTITUTION:A rotary position detection signal from a waveform shaper 9 and a rotating direction detection signal from a rotating direction detector 13 are inputted to a reset timing setter 15. A counter 18 which inputs the output of the setter 15 and the output of a waveform shaper 7 detects the rotating angle of a rotor magnet 4. Data to suppress the variation in the torque corresponding to the rotating angle of a rotor magnet 4 is read out from a ROM19 based on the rotary angle detection signal, the level of the motor control signal is controlled by the data, and supplied to a motor drive circuit.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to a rotation control device that reduces torque unevenness in a motor, particularly an electronic commutator motor, and realizes a reduction in rotational unevenness.

Conventional Structure and Problems In recent years, rotary head drive motors have been used in diagonal scanning type magnetic recording and reproducing devices (hereinafter referred to as VTRs) that record and reproduce video signals using a rotary head.

Small, highly efficient, and highly reliable DC electronic commutator motors have come to be used in cabzukun drive motors, reel drive motors, and the like.

Now, in such a VTR, video signals are recorded on a magnetic recording medium by a rotary head that is rotated at high speed by a rotary head drive motor, and if uneven rotation occurs in the rotary head drive motor, the time of the reproduced video signal will be affected. Since the shaft fluctuates, causing lateral wobbling in the reproduced image displayed on the television receiver and degrading the image quality, it is necessary to suppress the torque fluctuations generated by the rotary head drive motor, which is the source of uneven rotation, to a low level.

In addition, the audio signal is recorded by a head fixed to the tape running system, so if there is uneven rotation of the capstan drive motor that drives the tape, the reproduced audio signal will have wow, flutter, and noise. Therefore, it is necessary to suppress torque fluctuations, which are a cause of rotational unevenness, to a low level in the capstan drive motor as well.

Furthermore, to the reel drive motor:1.・If the torque fluctuations that occur are not suppressed, the tape tension in the tape running system will fluctuate, causing uneven rotation of the capstan drive motor and rotary head drive motor, resulting in sideways shaking of the reproduced image and reproduced audio. This will cause wow and flutter in the signal.

In this way, in VTRs and the like, in order to ensure the stability of reproduced signals, it is important to suppress fluctuations in the torque generated by the motor used.

Conventionally, in order to suppress rotational irregularities caused by such torque fluctuations generated by the motor, a method has been used in which the moment of inertia of the rotating body is increased and the gain of the control system is increased.

However, in order to reduce the weight and size of a portable VTR, when the moment of inertia of the rotary head drive motor and capstan drive motor is reduced and the motor is directly coupled, the rotational speed of the drive motor becomes low. Therefore, it is impossible to suppress rotational unevenness only by increasing the inertia moron I of the rotating body and increasing the gain of the control system as in the past.Objective of the InventionThe present invention solves the above-mentioned conventional problems. The object of the present invention is to provide a rotation control device that suppresses uneven rotation caused by fluctuations in motor torque.

Structure of the Invention The present invention provides means for generating N (N is an integer of 11) first rotational position detection signals during one rotation of a rotating body, and means for detecting the rotational direction of the rotating body and detecting the rotational direction. means for outputting a detection signal; means for generating M (M is a positive integer N) rotational speed detection signals during one rotation of the rotating body; A rotation angle of the rotating body 011 is detected from a delay circuit that outputs the output with a delay, and a second rotation position detection signal and the rotation speed detection signal that are output from the delay circuit, and a rotation angle corresponding to the rotation angle is detected. Detection signal? !
A rotation angle detecting means, a storage means storing torque fluctuation correction data for reducing torque fluctuations generated by the rotating body, and a circuit for amplifying or attenuating a control signal for controlling the rotation of the rotating body. 1) A gain control means whose gain is controlled by a torque fluctuation correction signal outputted from the storage means 11 corresponding to the rotation angle detection signal, and the delay circuit is configured to control the rotation direction detection signal and the delay amount. The configuration is such that a plurality of delay amounts can be set using a setting signal.

DESCRIPTION OF EMBODIMENTS Before entering into a detailed description of the present invention, torque fluctuations generated by an electronic commutator motor will be briefly explained. The motor used in the explanation of this embodiment is a 4-coil, 6-pole magnetized electronic commutator motor driven by 2-phase full-wave, but it should be noted that the present invention is also effective for motors with other configurations. Not even. FIG. 1d shows the rotor magnet 1 of the electronic commutator motor, and FIG. 1d shows the stator coil board 2. The rotor magnet 1-1 has S and N poles alternately magnetized at 60 degrees mechanical angle. In addition, there is a mechanical angle 9 on the stator coil board 2.
Stator coils L1, L2, L3, L4 with a pitch of 00
The portion from the center to the outer circumference of each coil has a width of 60 cv in mechanical angle.

In addition, the rotational position of the rotor magnet is detected and the coil L1~
A first Hall element H1 and a second Hall element H2 for controlling the timing of energizing L4 are provided at the midpoint between the coils L1 and L2 and between the coils L4 and Ll, respectively. FIG. 2 shows an example of a motor drive circuit. In Figure 2, AMP1, AMP2i differential 7'', INV
1-INV4 is an inverter, AND1 to AND4 are AND gates.

Hl-B2 is a Hall element, Trl to Tr8 are transistors, L1 to L4 are stator coils, R1 to R13 are resistors, and C1 and C2 are capacitors. When the rotor magnet 1 is rotating in the direction of the arrow 1a in FIG. 1a, the outputs Ha1 and Ha2 of the Hall element H1 and the outputs Hb1 and Hb2 of the Hall element H2 in FIG.
Output AB of ND2.

The waveforms of the output AB of AND3, AND, and the output AB of a are as shown in FIG. The output waveforms of the Hall elements H1 and B2 are repeating waveforms having one period in the section of one set of S and N poles of the rotor magnet 1, and one period in the rotation angle of 1200 degrees of the rotor magnet 1. From now on, the rotation angle of rotor magnet 1 is 1200 (mechanical angle 1200), which is electrical angle 3.
It is defined as 6o0. In addition, the Hall element H1 and the Hall element H
2 are attached at a pitch of 900 in mechanical angle, output waveforms Ha1°Hbl having a phase difference of 2700 in electrical angle, that is, 90°, are obtained. Ha2. Hb2 is Ha 1 respectively.

It becomes a signal with the opposite phase to Hbl. Ha 1 + Ha 2 is shaped into a rectangular wave A by the differential amplifier AMP1 and inverter INV1, and Hbl and Hb2 are shaped by the differential amplifier AM
The waveform is shaped into a rectangular wave B by P2 and inverter INV3. As shown in Fig. 3, the rectangular waves A and B have a phase difference of 9'lO0 in electrical angle, and INV2 creates an inverted waveform A of A, and INV4 creates an inverted waveform B of B.
and AB by AND gates AND1 to AND4
, AB, AE.

AB
It becomes a pulse wave of o9, A B −) A B −+
It is possible to obtain waveforms whose phase is delayed by 9σ in electrical angle in the order of A B → AB, and by these pulse waves, -C
Controls the timing of energization of the coils L1 to L4.

The period in which the output AB is high level is T1. The period in which the output AB is high level is T2. The period in which the output AB is high level is T3. T4 is the section where output AB is at high level.
Then, at T1, Trl.

Tr6 turns on, current flows from coil L3 to L1, and T
2, Tr3. Tr8 turns on and coil L4-+L2
A current flows in Tr2. Tr5 turns on, current flows from coil L1 to L3, and at T4, Tr4゜Tr7
turns ON and current flows from coil L2 to L4.

Next, the manner in which torque is generated by the motor will be explained. In FIG. 4, a sinusoidal magnetic field is formed by the NS alternating permanent magnets of the rotor magneto I-1. Each coil L1.
L2. L3. L4 each has a mechanical angle of 60° (i.e. N
or the width of one S permanent magnet). And these coils L1. L2. L3. L4
are arranged with a phase difference of 90' JL mechanical angle. Rotor magnet 1 and coil L1 when rotor magnet 1 is rotating. L2. The relative positional relationship between L3 and B4 is as shown in FIG. Ll at T1
Current flowing in and magnetic flux density curve B2. Torque is generated by the product of B3 and the product of the current flowing through B3 and the magnetic flux density curve B5°B6. At T2, the current flowing through B2 and the magnetic flux density curve B1
．． Product of B2, current flowing through B4, and magnetic flux density curve B4.
Torque is generated by the product of B5. At T3, torque is generated by the product of the current flowing through Ll and the magnetic flux density curves B3 and B4, and the product of the current flowing through B3 and the magnetic flux density curves Be and B1.

T4 is the product of the current flowing through B2 and the magnetic flux density curve B2°B3, and the current flowing through B4 and the magnetic flux density curve.

Torque is generated by the product of B6. Magnetic flux density curve B1゜B2
．． B3. B4. B5. Since the waveforms of coils L1 and B6 are the same, coils L1. L2. L3. If the current value flowing through L4 is constant, the torque fluctuation per rotation of the rotor magnet 1 is as shown in Fig. 6, where one period is the rotation angle (mechanical angle) 3o
It becomes a repeating waveform of O.

An embodiment of the present invention will be described below.

FIG. 6 shows a schematic configuration diagram of an embodiment of the present invention.

Reference numeral 3 designates an electronic commutator motor, which includes a six-pole magnetized rotor magnet 4 having the same structure as the rotor magnet 1 shown in FIG. 1A, and a stator coil board 5 having the same structure as the stator coil board 2 shown in FIG. and a light emitting element LED1. for rotational speed detection and rotational position detection. LED2, light receiving element P1. P2. It has a rotating plate R1. The rotating plate R1 and the rotor magnet 4 are fixed to the rotating shaft 6.

The rotating plate R1 has several slits 5Lit1 with equal width.
are provided, and a light emitting element LED1. Surin 1-5Lit1
．． The signal generated from the rotational speed detection means consisting of the light receiving element P1 is waveform-shaped into a rectangular wave by the waveform shaping circuit 7.
1, rJ - N2 pulses 41'1) per 401 revolutions of rotational speed detection fli No. 8. 1 rotary plate RI &C has 5 Lit slits for rotational position detection
2 is provided, and the light emitting element LED2゜Surin l-3Lit
2. The signal generated from the rotational 6-position detection means consisting of the light receiving element P2 is 1: bow t', and the waveform shaping circuit 5H (therefore, the first rotational 6-position detection signal of 1 pulse per rotation of the rotor magnet 401;'10). .

Hole level H3 provided on the stake coil board.
The output signal y from H4 is connected to resistors R1 and R2 shown in Fig. 2.
, R6, differential amplifier AMP1. Waveform shaping circuit 11 + resistor R31R41R6, differential 77b AMP2, rotation detection signal A whose waveform has been shaped by the waveform shaping circuit 12 similar to IINV3
, B are input to the rotation direction detection circuit 13. As mentioned above, the rotation detection signals A and B have a phase difference of 900 degrees from each other, and the rotation direction detection circuit 13 detects the rotation direction based on the phase lead/lag of these two signals A and B, and detects the rotation direction of the rotor magnet. 11. 4 is rotating clockwise (hereinafter referred to as CW force direction). At 'J', the rotational direction detection signal 14 is at a high level, and conversely, when rotating in the 'I' M l direction (hereinafter referred to as the CCW direction), the rotational direction detection signal 14 is at a low level.・Timing setting circuit 15
A predetermined amount of delay is set using the timing setting signal 16 and the rotational direction detection signal 14, and a second rotational position detection signal 17 which is the first rotational position detection signal 10 delayed by the predetermined amount is output. The rotational angle detection means is composed of a counter 18, which is reset at the rising edge of the pulse wave of the second rotational position detection signal 1, and counts the number of pulses of the rotational speed detection signal 8 to detect the rotor from the rotational position detection point. The rotation angle of the magnet 4 is detected.

The storage means 19 is usually a read-only storage device (hereinafter referred to as ROM).
It stores data for suppressing torque fluctuations corresponding to the rotation angle of the rotor magnet 4, and outputs a torque fluctuation correction signal (S2) corresponding to the rotation angle detection signal S1 obtained from the counter 18. .

The gain control circuit 20 is a circuit that amplifies or attenuates the control signal 21 that controls the rotation of the electric commutator motor 3, and is a circuit that amplifies or attenuates the control signal 21 that controls the rotation of the electric commutator motor 3.
2 controls its gain.

FIG. 7 shows how the torque fluctuation is reduced by the present invention. FIG. 7a shows a portion of the torque waveform shown in FIG. 5.

FIG. 7 shows the rotational speed detection signal 8. Figure 7 d is the first
The rotational position detection signal 10 indicates a case where the mounting position of the rotary plate R1 is accurately aligned with the rotor magnet 4. In FIG. 7e, the first rotational position detection signal 10 is reset to the rotational speed detection signal 8 by the reset timing setting circuit 15.
The second rotational position detection signal 17 delayed by three pulses is not shown. The counter 18 is reset to 0 at the rise of the pulse wave of the second rotational position detection signal 17, and
The address data becomes the torque fluctuation correction signal S2, and each time a pulse of the rotational speed detection signal 8 is input to the counter 18, the count value of the counter 18 increases by 1, and the it value S1
The contents of the ROM at the address corresponding to is output as the torque fluctuation correction signal S2, and the pattern of the torque fluctuation correction signal S2 is as shown in FIG. 7C.

In the torque waveform shown in Fig. 7a, the torque value when the rotation angle is θ is expressed as To(, so To('s - is 1.
B(of・IM-1......(1) (IM: motor drive current, lnisteator coil length).(However, 00≦θ(3600) Equation (1) ), what changes with the rotation angle θ is the magnetic flux density B(me) as shown in FIG. Depending on the motor control signal 21 and the gain control circuit, the motor drive current IM is set to a value I, (
Converting to IM(-Dc(θElectric.

Therefore, the value of torque after compensation W at rotation angle θ is Tc(=K11IB(−IM(1/)−l−)
1.K2.Eng.・e・・・・・・(4), which is constant regardless of the rotation angle θ, and torque fluctuation can be reduced.

In this embodiment, a ROM (Read Only Memory) is used as the storage means 19 for storing torque fluctuation correction data.
y), the actual torque fluctuation supplementary IF data becomes discrete data as shown in FIG. 7C. Torque fluctuation correction data stored in ROM DRc (a) is in ROM
It is written from address ○ to address (N2-1), and R
Torque fluctuation correction data DRc (K is an integer that satisfies ○≦ and ≦N2-1) is written to the address of OM (
K) is the following value.

When aligning the rotating plate R1 with the rotor magnet 4, it is very difficult to mechanically align it accurately, and conversely, if the position is misaligned, a significant torque fluctuation correction effect cannot be obtained. . In this embodiment, if mechanical positioning is performed with some degree of accuracy, a significant torque fluctuation correction effect can be obtained by electrically adjusting the timing of rotational position detection.

FIG. 8 shows a case where the first rotational position detection signal 10 is ahead of the original timing. FIG. 8a shows a portion of the torque waveform, similar to FIG. T a. FIG. 8 shows the rotational speed detection signal 8. FIG. 8d shows the first rotational position detection signal 10, which is three pulses ahead of the rotational speed detection signal 8 shown in FIG. 7d. (Hereinafter, one pulse of the rotational speed detection signal 8 will be referred to as one clock.) Therefore, the reset timing setting circuit 15 delays the rotational speed by six clocks (thereby obtaining the second rotational position detection signal 17 as shown in FIG. 8e). The second rotational position V1'' detection signal 17 shown in FIG. 8e has the same timing as the second rotational position detection signal 17 shown in FIG. When the signal S2 is increased to 14 degrees, a remarkable torque fluctuation effect of 11 times can be obtained.

FIG. 9 shows a case where the rotor magnet 4 is rotating in the opposite direction to that shown in FIG. 8. Figure 9a is Figure 8a
Similarly, it shows a part of the torque waveform.

FIG. 9 shows the rotational position detection signal 8. Figure 9 d is the first
The rotational position detection signal 10 is delayed by 30 degrees from that shown in FIG. Therefore, the reset timing setting circuit 15 sets the reset timing setting signal 16 to zero according to the change in the voltage level of the rotational direction detection signal 14 to the same extent as in the case of the rotational direction shown in FIG. As shown in Figure 9e, the second
The rotational position detection signal @17 is obtained. The second rotational position detection signal 17 shown in FIG. 9e has the same timing as the second rotational position detection signal 1a shown in FIG. 7e, so the torque fluctuation correction signal S2 as shown in FIG. 9C of? ? ), it is effective in compensating for significant torque fluctuations.

Figure 10 shows the first rotational position 1, contrary to the case shown in Figure 8.
This shows a case where the operation detection signal 10 is delayed from the original timing. The 1st o[ne 1a shows a part of the torque waveform similarly to FIG. 8. FIG. 10 shows the rotational speed detection signal 8. FIG. 10d shows the first rotational position detection signal 10, which is delayed by three clocks with respect to that shown in FIG. Therefore, by setting the delay amount of the reset timing setting circuit 16 to zero, a second rotational position detection signal 1 as shown in FIG. 10e is obtained. The second rotational position detection signal 17 shown in FIG. 10e has the same timing as the second rotational position detection signal 17 shown in FIG. 7e, so the torque fluctuation correction signal 82 as shown in FIG. It has a remarkable torque fluctuation correction effect! 1 to 1 to 0 FIG. 11 shows a case where the rotor magnet 4 is rotating in the opposite direction to that shown in FIG. Figure 11a is the 9th
Similar to Figure a, a portion of the torque waveform is shown. FIG. 9 shows the rotational speed detection signal 8. FIG. 11d shows the first rotational position detection signal shift 10, which is 3 times different from that shown in FIG. 7d.
Kronk is progressing. Therefore, the reset timing setting circuit 15v outputs the reset timing setting signal 16 while the rotation direction is the same as in the case of the rotation direction shown in FIG. 1Q.
Delayed knee due to changes in the voltage level of the J direction detection signal 14;
By setting J to 6 crosslocks, a second rotational position detection signal 17 as shown in FIG. 11e is obtained. The second rotational position detection signal 17 shown in FIG. 11e has the same timing as the second rotational position detection signal 17 shown in FIG.
2, and a remarkable torque fluctuation correction effect can be obtained.

FIG. 12 shows an example of the reset timing setting circuit 160 described in the following two-phase FIGS. 7 to 11. 12th
The delay amount setting of the reset timing setting circuit 15 shown in the figure is as shown in FIG.

In FIG. 13, ``H'' represents a high level, L°'' represents a low level, and the numerical values represent the amount of delay in terms of clocks. Note that a detailed explanation of the reset timing setting circuit 16 will be omitted here since it is not directly related to the present invention. Further, when the rotation direction is CW, the rotation direction detection signal 14 is at the high level, and when the rotation direction is CCW, the rotation direction detection signal 14 is at the low level.

Therefore, in this embodiment, if B1 and B2 of the reset timing setting signal 16 are set so as to correct the timing deviation of the first rotational position detection signal 1°, the rotor magnet 4
A remarkable torque fluctuation correction effect can be obtained regardless of the direction of rotation.

Further, in the present invention, the Hall element H3,
An example using H4 was shown, but for example, an additional 5 Lit on the rotating plate
It is also possible to provide 5Lit3 (not shown) in a different radial direction from 1.5Lit2 and extract a signal similar to that of Hall elements H3 and H4, and the present invention is also applicable to these optical rotational position detection methods. Not even.

Further, as another embodiment of the present invention, the stator coil energization switching signal output from the Hall elements H3 and H4 is
It may also be used as a rotational position detection signal. In this case, the first co-rotation position detection signal is the rotation angle 3 of the rotor magnet 4.
It is output every σ, and 12 times during one rotation of the rotor magnet 4.
It becomes a pulse signal. In this embodiment, the explanation of the torque fluctuation correction and the explanation of the correction of the timing deviation of the first rotational position detection signal will be omitted as they are the same as described in the first embodiment, but in this embodiment, the ROM ] Jin 1,
The capacity W of the ROM of the first embodiment is required to be 1/12, and the rotational position detection inclination generating means consisting of 5Lit2, the light emitting element LED2, and the light emitting element P1 is safe.

Effects of the invention (1) Motors, especially electronic commutator motors, can be made smaller and lighter, and rotational unevenness can be reduced when the rotational speed is lowered.
Achieves stable rotation performance.

(2) Even if there is a slight deviation in the position adjustment of the rotational position detection signal generation means, a remarkable torque fluctuation correction effect can be obtained.Moreover, when the rotational direction is switched, the rotational direction is detected and the rotational position detection signal is automatically adjusted. If the timing is set and the reset timing setting signal is determined, a remarkable torque fluctuation correction effect can be obtained regardless of the rotation direction.

[Brief explanation of drawings]

Figure 1a is a plan view of the rotor magnet of a 4-coil, 6-pole magnetized electronic commutator motor, the same figure is a plan view of the stator coil board, and Figure 2 is a plan view of the electronic commutator motor shown in Figure 1. An electric circuit diagram showing an example of the drive circuit, Fig. 3 is an auxiliary diagram explaining the timing of energizing the motor coils, and Fig. 4 shows the positions of the coils and rotor magnets when switching 1E to each coil. FIG. 6 is a diagram showing torque fluctuations, FIG. 6 is a block diagram of an embodiment of the rotation control device of the present invention, and FIGS. 7 to 13 are diagrams showing an embodiment of the present invention. It is an auxiliary figure for explanation. 1.4...Rotor magnet, 2...
Stator coil, 3...-Electronic commutator motor, 5
...Stator coil board, 6 ...Rotating shaft, 7, 9, 11.12 ... Waveform shaping circuit, 8
...Rotation speed detection signal, 10...f5
r, rotation of 1 ~>: j"i", detection slope ';)',
13...Rotation direction detection circuit, 14...Rotation direction detection signal, 16...Reset timing setting circuit, 16...Return timing setting signal,
17...Second rotation fshi1i/, 1 detection signal,
18...Counter, 19...Memorizing I'
y,, 2o...Gain control circuit. Ikirito's name Patent attorney Toshio Nakao and 1 other person No. 1@rano (b) Fig. 4 Fig. 5rIA (Kaba/Yi; corner) Fig. 7 Fig. 8 e) Fig. 9 Fig. 10

Claims (1)

[Claims] (1) During one rotation of the rotating body, N (N is a positive integer) first
means for generating a rotational position detection signal; means for detecting the rotational direction of the rotating body and outputting a rotational direction detection signal; and M (M is a positive integer N) during one rotation of the rotating body. )
means for generating a rotational speed detection signal, a delay circuit that delays and outputs the first rotational position detection signal, and a second rotational position detection signal that is an output of the delay circuit and the rotational speed detection signal. , a rotation angle detection means for detecting a rotation angle of the rotating body and obtaining a rotation angle detection signal corresponding to the rotation angle; and a memory storing torque fluctuation correction data for reducing torque fluctuations generated by the rotating body. ．． (1 means, and a circuit for amplifying or attenuating a control signal for controlling the rotation of the rotating body, the gain of which is controlled by a torque fluctuation correction signal output from the storage means in response to the rotation angle detection signal. A rotation control device for a rotating body, characterized in that the delay circuit has a gain control means configured to control the rotation direction, and the delay circuit can be set to a plurality of delay amounts using the rotation direction detection signal and the delay amount setting signal. The rotation control device for a rotating body according to item 1, wherein the first rotational position detection signal uses a rotational position detection signal for driving and controlling the rotating body.