JPS60121986A - Rotation controller of rotor - Google Patents

Abstract

PURPOSE:To correct a rotating position detection signal by generating a rotating position detection signal during one rotation of a rotor and delaying the detection signal. CONSTITUTION:When the first rotary position detection signal 11 is advanced by two clocks with respect to the original timing, a reset timing setter 12 is used to delay 4 clocks, thereby obtaining the third rotary position detection signal 14. Thus, data pattern of torque variation correction can be obtained at the timing of obtaining the torque variation correcting effect. When the signal 11 is delayed by 2 clocks with respect to the original timing, the setter 12 is used to set the delay amount to zero, thereby correcting the torque variation.

Description

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

Conventional configuration and its problems In recent years, diagonal scanning magnetic recording and reproducing devices (hereinafter referred to as Video Tap), which record and reproduce video signals using a rotating head, have been developed.
Small, highly efficient, and highly reliable direct current electronic commutator motors are directly coupled and used in rotary head drive motors, capstan drive motors, reel drive motors, etc. used in e-recorders (abbreviated as VTRs). It became so.

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 change. As the shaft fluctuates, the reproduced image displayed on the television will be swayed, causing deterioration in image quality. Therefore, it is necessary to suppress fluctuations in the torque generated by the rotation and gutter drive motors, which are the cause of uneven rotation.

In addition, the audio signal is recorded by a head that is fixed to the tape running system 1j, and if rotational unevenness occurs in the cab scan drive motor that drives the tape running, the reproduced audio signal will have a period of time called wow and flutter. Since shaft fluctuations occur and cause deterioration of the audio signal, it is necessary to suppress torque fluctuations, which are the cause of uneven rotation, to a low level in the capstan drive motor as well.

Furthermore, in the reel drive motor, if the generated torque fluctuations are not suppressed, the Dave tension in the tape running system will fluctuate, causing rotational irregularities in the capstan drive motor and rotary head drive motor, resulting in sideways shaking of the reproduced image. , which causes wow and burble in the reproduced audio 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 l/lux fluctuations generated in the motor, methods have been used to increase the moment of inertia of the rotating body and increase the gain of the control system.

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 a direct drive is used, the rotational speed of the drive motor becomes low. Therefore, it is impossible to suppress rotational irregularities by increasing the moment of inertia of the rotating body and increasing the gain of the control system as in the conventional method.

OBJECTS OF THE INVENTION The present invention solves the above-mentioned conventional problems and aims to provide a control system that suppresses uneven rotation due to fluctuations in motor torque.

Structure of the Invention The present invention provides means for generating N (N is a positive integer) first rotational position detection signals during one rotation of a rotating body, and a means for delaying the first rotational position detection signals. a delay circuit; a means for generating M (Mil: M>N positive integer) second rotational position detections (iT4;'' during one rotation of the rotating body;
Rotation angle detection means for detecting a rotation angle of the rotary body from a third rotation position detection signal that is an output of the delay circuit and the second rotation position 1ρ output signal, and generating a rotation angle detection signal; i) A circuit for amplifying or attenuating a control signal for controlling the rotation of the rotating body; a storage means storing a torque fluctuation correction signal for reducing torque fluctuations generated by the rotating body; (The gain II control means whose gain is controlled by the i-lux fluctuation correction signal outputted from the 11th stage in response to the rotation angle detection signal is destroyed, and the delay circuit is controlled by the delay g:n? setting signal. Delay 1 which can be set to multiple delay 7 by bow!! ↑11 is made by 1 path.

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 that is driven by 2-phase full pumping, but it should be noted that the present invention is also effective for motors with other configurations. Not even. FIG. 1a shows a rotor magnet 1 of an electronic commutator motor, and FIG. 1 shows a stator coil board 2. FIG. The rotor magnet 1 has S and N poles alternately magnetized at every 600 mechanical angles. In addition, there is a mechanical angle 9 on the stator coil board 2.
Stator coils L1, L2, L3, L4 with a pitch of 0°
are arranged, and the portion from the center of each coil toward the outer periphery has a width of 60° in machine fiJ. The first Hall element H1 and the second Hall element H2, which detect the rotational position of the rotor magnet and control the timing of energizing the coils L1 to L4, are located at the midpoint of the coils L1 and L2, and between the coils L4 and Ll, respectively. It is set at the midpoint of FIG. 2 shows an example of a motor drive circuit. In Fig. 2, AMPl, A
MP2 is a differential 7 amplifier, engineering Nv1 to I NV41d (member 1, AND1 to AND4 are anod gates, Hl-B
2 is a Hall element, Tri to Tr8 are transistors, Ll
~L4 is the stator coil, R1-R13 is the resistance, C1・
C2 indicates a capacitor. When the rotor magnet 1 is rotating in the direction of the arrow 1a in Fig. 1a, the outputs Ha1 and Ha2 of the pole element H1 and the outputs Hb1 and Hb2 of the Hall element H2, the output AB of AND1, and the output of AND2 in Fig. 2 AB , AND3 output AB , AND4 output AB
The waveforms of are shown in FIG. Hall element H1
, H2 is a manipulated waveform that has one cycle in the section of one set of S poles of rotor magneto 1-1, N46<,
A rotation angle of 1200 of the rotor magnetic throat 1 corresponds to one cycle. Hereinafter, the rotation angle of 120 degrees (mechanical angle of 1200 degrees) of rotor magnet 1.1 will be defined as the electrical angle of 360 degrees. ) Hall element H1, etc. ;) -- Hall element H2 is arranged at a pitch of 900 in mechanical angle, so it is 2700 in electrical angle.
That is, the output waveform Ha1. has a different phase by 90'1. Hb1
is obtained.

Ha2. Hb2 becomes a signal with a phase opposite to that of Ha 1 + Hbl. Hal and Ha□ are differential amplifiers AMP1
The waveforms of Hbl and Hb2 are shaped into a rectangular wave A by an inverter INV1, and the waveforms of Hbl and Hb2 are shaped into a rectangular itB by a differential amplifier AMP2 and an inverter INV3. As shown in Figure 3, the rectangular wave B has a phase difference of 900 in electrical angle, and INV2 converts the inverted waveform A of A, and INV4 converts the inverted waveform B of B into a rectangular wave. , AB , AB , by Antogame 1・AND1~AND4
When AB and AB are obtained, as shown in Fig. 3, each becomes a high level in the section of electrical angle 9o0, and becomes a pulse wave with a period of electrical angle 360°, and AB-AB-AB-AB
It is possible to obtain waveforms whose phases are delayed by 900 electrical degrees from l1li, respectively, and the timing of energization of the coils L1 to L4 is controlled by these pulse waves.

T1 is the section where the output AB is high level, T2 is the section where the output AB is high level, T3 is the section where the output AB is high level, and T is the section where the output AB is high level.
4, in the motor drive circuit shown in Fig. 2,
At T1, Trl and Tr6 are turned on and coils L3-L1
A current flows through Tr3 at T2. Tr8 turns on, current flows through coil L4-L2, and at T3, Tr2. T
r5 turns on, current flows through coils L1-Ls, and T4
Then, Tr4 and Tr7 are turned 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 alternating NS permanent magnets of the rotor magnet 1. Each coil L1,
B2, B3, and B4 each have a mechanical angle of 600 (i.e., N-1/ is the width of one S permanent magnet) and have a width of 11. And these coils L1. L
2. L3. L4 are arranged with a phase difference of 9o0 mechanical angle.

Rotor magnet failure when rotor magnet is rotating
-1 and coil L1, B2. B3. The positional relationship of B4 with respect to phase 7J is as shown in FIG. At T1, the current flowing through Ll and the magnetic flux density curve B2. The product of B3 and the current flowing through B3 and the magnetic flux density curve Bes.

Torque is generated by the product of B6. At T2, the product of the current flowing through B2 and the magnetic flux density curve B1 and B2, and the current flowing through B4 and the magnetic flux density curve B4. Torque is generated by the essence of B5.

At T3, the current flowing through Ll and the magnetic flux density curves B3 and B4
Torque is generated by the product of the current flowing through B3 and the magnetic flux density curves Bs and B1. At T4, the current flowing through B2 and the magnetic flux density curve B2. Torque is generated by the product of B3, the current flowing through B4, the magnetic flux density curves Bts, and B6. Magnetic flux density curves B1, B2. B3. B4. B5. Since the waveforms of coils L1 and B6 are the same, coils L1. L2゜B3. If the current value flowing through B4 is constant, the torque fluctuation per 101 rotations of the rotor magnet will be a repetitive waveform in which one cycle is a rotation angle (mechanical angle) of 30 degrees, as shown in FIG. An example will be explained.

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

3 is an electronic commutator motor with a six-pole magnetized rotor magnet l-4 having the same structure as the rotor magnet shown in Fig. 1a.
A stator coil board 5 having the same structure as the stator coil shoulder board 2 shown in FIG.
D2, light receiving element P1. It has P2. The motor drive circuit 6 is the same as the circuit shown in FIG. Rotating plate R1
The rotor magnet throat 4 is fixed to the rotating shaft 7. 12×N1 provided at equal pitches on the outer periphery of rotating plate R1
(N1 is an integer of 2 or more) 5LiT1, light emitting element LE
The signal output from the second rotational position detection signal generating means, which is composed of D1 and light receiving element P1, is waveform-shaped by the waveform shaping circuit 8 and is converted into a waveform of (12×N1) per 11111 rotations of the rotor magnet and throat 4. This becomes the second rotational position 1 detection signal 9. Similarly, the rotational position detection signal generation means, which is provided on the inner circumference of the rotary plate R1 and is composed of 5LiT2 for rotational position detection, a light emitting element LED2, and a light receiving element P2, outputs the signal. First rotational position detection (Li No. 11) of 1 pulse per rotation of C waveform-shaped halo tomamagnetic cutter 4. The first rotational position detection signal 11 is a reset timing setting circuit 12 which is a delay circuit.
A third rotational position detection signal 14 is obtained which is inputted into the rotational position detection signal 9 and delayed by a predetermined number of pulses of the rotational position detection signal 9 by the driver throat timing setting signal 13.

The second rotational position detection signal 9 generates 12×N1 pulses between the rising edge of the pulse of the third rotational position detection signal 14 and the rising edge of the next pulse. The rotation angle of the rotor magnet 4 can be detected.

The torque fluctuation correction circuit of the present invention is a rotation angle detection counter that detects the rotation angle of the rotor magnet 4 from the rotation position detection point using the third rotation position detection signal 14 and the second rotation position detection signal 9. 16. Storage means 16 that stores components for reducing torque fluctuations of the electronic commutator motor 3 corresponding to the rotation angle of the rotor magnet 4; amplifying or The attenuation circuit is composed of a gain I control circuit 18 whose gain is controlled by the torque fluctuation correction signal S1 output from the storage means 16.

The counter 15 is reset when the pulse wave of the third rotational position detection signal 14 rises, and the counter 15 is reset when the pulse wave of the third rotational position detection signal 14 rises.
The rotation angle of the rotor magnet 4 is detected by counting the number of pulses.

The storage means 16 is usually a read-only storage device (hereinafter referred to as ROM).
) is used to store data that should suppress torque fluctuations corresponding to the rotation angle of the rotor magnet 4.
A torque fluctuation correction signal S1 corresponding to the rotation angle detection signal S2 output from the counter 16 is output.

Fig. 7 shows how the torque fluctuation is reduced by 1v of misfire. FIG. 7a shows a part of the torque waveform shown in FIG. 6, and FIG. 7a shows the second rotational position detection signal 9. Figure 7C
Z) is stored in the storage means 16 and indicates a pattern of data for torque fluctuation correction. Figure 7d shows the first rotational position 1v.
1 detection signal 11 is shown, indicating a case where the positional relationship between the rotating plate R1 and the rotor magnet 4 is correct. FIG. 7e shows the third rotational position detection signal 14. If one pulse of the second rotational position detection signal 9 is called a clock, then
The third rotational position detection signal 14 is delayed by two clocks by the reset timing setting circuit 12, and at this timing, the torque fluctuation correction data pattern shown in FIG. 7C becomes the torque waveform shown in FIG. 7a. The pattern is the opposite of the above, and a significant correction effect on torque fluctuations can be obtained.

Note that the reason why the third rotational position detection signal 14 is delayed by two clocks with respect to the first rotational position detection signal 11 when the positional relationship between the rotary plate R1 and the rotor magnet 4 is correctly matched will be described later. do. L sea urchin, first rotation position 11
This is to enable correction of a timing deviation of ±2 clocks of the '1 detection signal 11.

In the torque waveform shown in Fig. 7a, the torque value when the rotation angle is θ is expressed as To(θ).
・B(の・ IM-1・・・・・・・・・・・・(1)
1M: Motor drive current l is the length of the coil. In equation (1), what changes depending on the rotation angle θ is the magnetic flux density B(θ), as shown in FIG. On the other hand, if the torque fluctuation correction data corresponding to the rotation angle θ is set to DC(), the motor drive current IM is changed to a value I corresponding to the rotation angle θ by the motor control signal 17 and the gain control circuit 18.
When converted to M(, it becomes I, ('s = Dc('s · Ia).

Therefore, the corrected torque value Tc (of
keTc(no-ni1.B(no' IM(no・l2K -K
・■ ・4 ・・・・・・・・・・・・(4) 2a Therefore, it becomes constant regardless of the rotational position θ, and torque fluctuation can be reduced. 7. Storage means for storing normal torque fluctuation correction data Since a ROM is used in 16, the actual torque fluctuation correction data becomes discrete data as shown in FIG. 7C. Torque fluctuation correction data DRc stored in ROM
The count value of the counter 15 is reset to O at the rising edge of the pulse of the third rotational position detection signal 14, and the data at address 0 of the ROM is written as the torque. The fluctuation correction signal S1 is generated, and thereafter, each time the rotor magnet 4 rotates and the pulse wave of the rotation speed detection signal 9 is input, the count value of the counter 15 increases by 1, and the ROM written in the address corresponding to the count value The contents are output as the torque fluctuation correction signal S1.

Here, the ROM address is the address (K is 0≦≦(12X
The torque fluctuation correction data DRc(6) written in the integer (N1-1) is the following value.

By the way, the torque fluctuation correction explained above is for the case where the positional relationship between the rotating plate R1 and the rotor magnet 4 is correct, and when mass producing the electronic commutator motor 3, the positional relationship between the rotating plate R1 and the rotor magnet 4 must be correct. If you try to match it, it will be difficult to adjust the rotary plate R1 to the rotary shaft 7, so in this embodiment, the first rotational position detection signal 11 is shifted by ±2 clocks from the original timing. Even in this case, it is possible to obtain the same torque fluctuation correction effect as when the position is correct. First, FIG. 8 shows a case where the first rotational position detection signal 11 has advanced by two clocks with respect to the original timing. Figure 8a shows the torque waveform -f~(5 minutes), Figure 8a shows the second rotational position detection signal 9; Figure 8d shows the first rotational position detection signal 11; It is two clocks ahead of the first rotational position detection signal 11 shown in FIG. 7 (d). By delaying it by four clocks using the reset timing setting circuit 12 at L, the signal is shown in FIG. 8 (d). :The third rotational position detection signal 14 can be obtained, and therefore, as shown in FIG. 8C, the data pattern for torque fluctuation correction is generated at a timing when a significant torque fluctuation correction effect can be obtained, as in FIG. 7C. Obtainable.

Next, FIG. 9 shows a case where the first rotational position detection signal 11 is delayed by two clocks with respect to the original timing. Figure 9a
is a part of the torque waveform, and FIG. 9 shows the second rotational position detection signal 9. FIG. 9d shows the first rotational position detection signal 1.
1 and the first rotational position detection signal 1 shown in FIG.
It is 2 clocks behind 1. Therefore, by setting the delay -; to zero using the reset timing setting circuit 12, it is possible to obtain the third rotational position detection signal 14 as shown in FIG. 9d, and therefore as shown in FIG. 9C. ,
Similar to FIG. 7C, the data pattern for torque fluctuation correction can be obtained at a timing when a significant torque fluctuation correction effect can be obtained.

FIG. 10 shows the reset timing setting circuit 12 of this embodiment.
An example is shown below. As the reset timing setting signal 13, B1. When two signals of B2 are input and B1 is low level, the delay amount is zero, B1 is high level and 82 is low level, 6 levers, delay amount is 2 clocks.If both B1 and B2 are low level, the delay amount is zero. is 4 clocks, and the delay amount can be switched in three ways by the reset timing setting circuit 13.
The timing can be electrically adjusted without mechanical adjustment for the timing deviation of No. 7 and 11.

A detailed explanation of the reset timing setting circuit 12 will be omitted here since it is not directly related to the present invention.

Furthermore, the delay II; can also be freely set.

Further, in the present invention, an example has been shown in which Hall elements H1 and H2 are used as rotational position detection elements for controlling energization switching of the stator coil of the motor, but for example, 5LiT1.
It is also possible to install 5LiT3 (not shown) in a different radial direction from 5LiT2 and extract signals similar to those of Hall elements H1 and H2, and an optical rotational position detection method that optically detects all of these rotational information signals can be used. Needless to say, the present invention can also be applied.

Further, as another embodiment of the present invention, the stator coil energization switching signal output from the Hall elements H1 and H2 is
It may also be used as a rotational position detection signal. In this case, the first rotational position detection signal is output at a rotation angle of 30°477 of the rotor magnet 4, and becomes a signal of 12 pulses during one rotation of the rotor magnet 4. In this embodiment, explanation of torque fluctuation correction and detection of timing deviation of the first rotational position detection signal will be omitted since they are the same as described in the first embodiment. The capacity is only 1/12 of the capacity of the ROM of the first embodiment, and there is an advantage that there is no need for the rotational position detection signal generating means consisting of the capacitor 5LiT2, the light emitting element LED2, and the light receiving element P2.

Effect of the invention 0) It is possible to reduce the size and weight of a motor, especially an electronic commutator motor, reduce uneven rotation when the rotation speed is lowered, and realize stable rotation performance.

(2) There is no need to mechanically improve the alignment accuracy of the rotational position detection signal, and the rotational position detection signal can be corrected to a highly accurate rotational position detection signal using an electrical signal, so that torque fluctuation correction can be easily performed.

[Brief explanation of the drawing]

Fig. 18 is a 317-plane view of the rotor magnet of a 4-coil, 6-pole magnetized electronic commutator motor, b is a plan view of the same stator coil board, and Fig. 2 is a 317-plane view of the rotor magnet of the electronic commutator motor shown in Fig. 1. An electric circuit diagram showing an example of the drive circuit, and Figure 3 is an auxiliary diagram explaining the timing of energizing the motor coil.
FIG. 4 is a diagram showing the positions of the coils and rotor magnets when switching the energization to each coil, FIG. The same embodiments as shown in Fig. 7 and Fig. 8 and Fig. 9 will be explained below.
), and FIG. 10 is a circuit diagram of the recess/node timing setting circuit of the same embodiment. 1...Rotor magnet, 2...Stator coil board, 3...Electronic commutator motor, 4...
... Rotor magnet, 5 ... Stator coil board, 6 ... Motor drive circuit, 7 ... Rotating shaft, 8, 10 ... Waveform shaping circuit, 12. ...
...Reset timing setting circuit, 15...Counter, 16...Storage means, 18...
Gain control circuit. Name of agent: Patent attorney Toshio Nakao and 1 other person No. 3
Fig.4 Fig.5 Fig.6

Claims (2)

[Claims] (1) During one rotation of the rotating body, N (N is a positive integer) first
means for generating a rotational position detection signal of the rotating body; a delay circuit that delays the first rotational position detection signal;
means for generating M (M is an integer of M)N iE second rotational position detection signals during rotation; a third rotational position detection signal which is an output of the delay circuit; detecting the rotation angle of the rotating body from a second rotational position detection signal;
a rotation angle detection means for generating a rotation angle detection signal; a storage means for storing torque fluctuation correction data for reducing torque fluctuations generated by the rotating body; The delay circuit has gain control means that is an amplification or attenuation circuit and whose gain is controlled by a torque fluctuation correction signal outputted from the storage means in response to the rotation angle detection signal, and the delay circuit A rotation control device for a rotating body, characterized in that a plurality of delay amounts can be set according to a setting signal. (2) In the rotation control device for a rotating body according to claim 1, the first rotational position detection signal is a rotational position detection signal for driving and controlling the rotating body. Body rotation control device.