JPH058621U - Rotation control device - Google Patents

Abstract

(57) [Summary] [Purpose] An FC sensor and an FG magnet are used as the PG sensor and the PG magnet, and the installation thereof is omitted to obtain a small rotation control device. [Structure] A part of a magnetizing pattern 17 of the FG magnet 10 and another magnetizing pattern are made different from each other, and the rotary cylinder 1
The output from the FG sensor 5 during rotation is used as rotation speed control and rotation phase information.

Description

[Detailed description of the device]

[0001]

[Industrial applications]

  The present invention relates to a rotation control device in a recording / reproducing device such as a VTR or DAT. It is something.

[0002]

[Prior art]

  FIG. 12 shows a conventional rotation control device disclosed in Japanese Utility Model Laid-Open No. 2-35347. FIG. 1 is a block diagram, in which 1 denotes a magnetic recording / reproducing operation for a magnetic tape 2. The rotary cylinder 4 equipped with the magnetic head 3 rotates the rotary cylinder 1. A motor for driving 5 is an FG sensor for detecting the rotation speed of the rotary cylinder 1, and 6 is Compare the FG output corresponding to the specified speed with the actual FG output from the FG sensor 5. A speed servo circuit 7 for detecting the rotation angle of the rotary cylinder 1 during one rotation P The G sensor 8 is a unit for comparing the output signal from the PG sensor 7 with the set period. The phase servo circuit 9 is output from the speed servo circuit 6 and the phase servo circuit 8 described above. A motor for controlling the rotation speed of the motor 4 in response to an error signal from a specified rotation speed It is a control circuit.

[0003]   FIG. 13 is a front view schematically showing a part of the configuration of the block diagram of FIG. In FIG. 10, 10 is integrally rotated coaxially with the rotary cylinder 1 and has a circumferential direction on its circumferential surface. About 20 pairs of N and S poles, for example, 24 pairs are magnetized at equal intervals. It is the FG magnet which was made. 11 rotates integrally with the rotary cylinder 1 coaxially, One or more in the circumferential direction, for example, one N pole on one side and the other 180 degrees opposite It is a PG magnet having one S pole at a position.

[0004]   14 to 19 show a specific configuration example of a conventional rotation control device. In FIG. Reference numeral 12 is a lower cylinder located below the rotary cylinder 1, and is provided on the shaft 13 and the bearing 14. The rotary cylinder 1 is rotatably supported. 15 is fixed to the rotary cylinder 1 Rotor consisting of fixed permanent magnet, 16 is fixed to the lower cylinder 12 It is a stator equipped with a child coil.

[0005]   FIG. 15 is a perspective view showing only the motor 4 shown in FIG. 14, and in FIG. 5a is an FG provided in a rectangular shape at equal intervals in the circumferential direction of the FG sensor 5. Pattern 5b is an FG output showing the voltage generated at both ends of this FG pattern 5a. It

[0006]   FIG. 16 shows the PG magnet 11 and the PG sensor 7 facing each other. FIG. 17 is a perspective view showing the rotor 15 of FIG. 15 seen through from the lower surface of the FG pattern 5a. It is the figure which looked at. In the figure, 17 is an equal mark in the circumferential direction of the FG magnet 10. It is a magnetization pattern showing a state in which N poles and S poles are alternately magnetized at different angles θ. It

[0007]   FIG. 18 is a block diagram showing the configuration of the phase servo circuit 8 described above. 18 is the PG output which is the output from the PG sensor 7, and 19 should be recorded. Video input signal, 20 is obtained from the magnetic tape 2 via the magnetic head 3 during reproduction. Playback control signal, and 21 is the video input signal 19 at the time of recording and the playback signal at the time of playback. It is a comparator input terminal for inputting the signal control signal 20. 22 is based on the above PG output 18 A comparator for comparing with a constant value, 23 is a PG error output from the comparator 22, and E1 is P A lead error which is an error output of the comparator 22 when the phase of the G output 18 leads the regulation. , E2 are error outputs of the comparator 22 when the phase of the PG output 18 is behind the regulation. It is a delay error.

[0008]   FIG. 19 is a block diagram showing the configuration of the speed servo circuit 6 described above. Here, 24 is the FG output which is the output from the FG sensor 5, and 25 is the FG output 2 A flip-flop circuit for converting 4 into a rectangular shaped wave, 26 is a flip-flop circuit. Gate pulse circuit for setting the reference value of the output of the loop circuit 25, 27 is a gate pulse circuit The set voltage for line 26, 28 compares the FG output 24 with a specified value and outputs an error signal. The comparator, 29 is the FG error which is the output of this comparator 28, and F1 is the FG output 2 4 is a high-speed error which is the output of the comparator 28 when the frequency is faster than the standard, F2 is FG This is a low-speed error that is the output of the comparator 28 when the frequency of the output 24 is slower than specified. .

[0009]   Next, the operation of the above configuration will be described. 12 to 19, the rotary series The following structure is adopted so that the binder 1 rotates at a constant relative speed with respect to the magnetic tape 2. Has been done.   The FG sensor 5 has a magnetized pattern 17 in the circumferential direction while the FG magnet 10 is rotating. An FG output 24 is generated when traversing the FG pattern 5a.

[0010]   In the block diagram of the speed servo circuit 6 shown in FIG. The output from the comparator 28 is rotated by the gate pulse circuit 26, which is controlled by the gate pulse circuit 26. When the rotational speed of the binder 1 is high, the high speed error F1 is a small FG error 29, and When the rotation speed of the rotary cylinder 1 is slower than the constant value, a large FG error 29 is a low speed error F It becomes 2. 14 and 16, the PG magnet 11 and the PG sensor 7 are When facing each other, a pulse like the PG output 18 is generated.

[0011]   On the other hand, in the block diagram of the phase servo circuit 8 of FIG. 2, the video input signal 19 is input to the comparator input terminal 21 and the PG output 1 Compared with 8. The phase of the output from the comparator 22 is greater than the PG output 18 by definition. If it has proceeded, the advance error E1 which is a small PG error 23 will result, and the PG output 18 will be If it is behind the regulation, the delay error E2 is a large FG error 23. Also, During reproduction, the magnetic tape 2 on which the video input signal 19 during recording is recorded. By reproducing, the reproduction control signal 20 is input to the comparator 22.

[0012]   Hereinafter, a speed and phase control operation common to both recording and reproduction will be described. Rotating series It is an error depending on whether the rotation of the binder 1 is fast or slow. In other words, the speed servo circuit 6 And the FG error 29 and the PG error 23 according to the magnitude of the output of the phase servo circuit 8. The voltage is applied from the motor control circuit 9 to the motor 4 in order to reduce the The rotation of 1 is controlled to the regulation.

[0013]

[Problems to be solved by the device]

  Since the conventional rotation control device is configured as described above, the control of the rotary cylinder 1 is suppressed. The FG sensor 5 and the FG magnet 10 and the PG sensor 7 and the PG magnet Each net 11 is required, and this is an obstacle to miniaturization of the rotation control device. It was.

[0014]   This invention was made in order to solve the above problems, and an FG sensor And FG magnet are combined to use both PG magnet and PG sensor. To provide a rotation control device capable of reducing the number of parts and downsizing. And

[0015]

[Means for Solving the Problems]

  The rotation control device according to the present invention uses a part of a plurality of magnetization patterns of the FG magnet. The rotation of the rotating cylinder is controlled by the output of the FG sensor while being different from other magnetization patterns. It is characterized by being configured to perform rolling speed control and rotation phase control.

[0016]   Further, a difference between a part of a plurality of magnetization patterns of the FG magnet and another magnetization pattern The point may be the magnetizing strength.

[0017]

[Action]

  According to this invention, when the rotary cylinder makes one rotation, the output of the FG sensor is It is possible to obtain signals with different output magnitudes at a rate of once or more per rotation, The time when the magnitude of the FG output changes is used as the time when the PG output occurs. By doing so, it is possible to control the rotation speed and rotation phase of the rotating cylinder. Wear.

[0018]

【Example】   An embodiment of the present invention will be described below with reference to the drawings.   FIG. 1 is a block diagram showing the configuration of a rotation control device according to an embodiment of the present invention. In this figure, the difference from the conventional example shown in FIG. 12 is that the PG sensor 7 of FIG. It is omitted and corresponds to the outputs of the PG sensor 7 and the FG sensor 5. A filter 30 for separating and outputting information according to the output of the FG sensor 5 is newly provided. That is what is done. 3 corresponds to a side sectional view of the conventional example shown in FIG. In this embodiment, the PG magnet 11 and the PG sensor 7 shown in FIG. 14 are used. Can be omitted to reduce the radial distance between the rotor 15 and the lower cylinder 12. It is possible.

[0019]   FIG. 2 is a block diagram showing the detailed structure of the filter 30. 31 is a limiter for converting the output of the FG sensor 5 into a rectangular wave only when the output is a certain value or more. Numeral 32 denotes an amplitude adjustment for amplifying the output amplitude of the FG sensor 5 to make the amplitude values constant. , Tf is a rotation cycle indicating a cycle of one rotation of the rotary cylinder 1, and T is a rotation cycle of the FG sensor 5. It is a 1FG period indicating the adjacent wave period of the output signal.

[0020]   FIG. 4 shows, on an FG sensor 5, an embodiment embodying the configuration of FIG. FIG. 2 is a plan view showing the FG magnet 10 superimposed from above, in which FIG. , 17h, 17i, 17j, and 17k respectively indicate a magnetization pattern, 5ah, 5ai. 5aj and 5ak are under the above-mentioned magnetizing patterns 17h, 17i, 17j and 17k. It is the FG pattern located on the other side. Of the above magnetizing patterns, the magnetizing pattern Area 17j is longer than the other magnetizing patterns 17h, 17i, 17k in the radial direction and has an area Is large. Further, among the above-mentioned FG patterns, the FG pattern 5aj is the other FG pattern. The width in the radial direction is larger than that of the patterns 5ah, 5ai and 5ak.

[0021]   Next, only the main points of the operation of the above configuration will be described.   When the magnetization pattern 17j and the FG pattern 5aj shown in FIG. , When the other magnetic patterns 17h, 17i, 17k and the FG pattern 5aj overlap. And the FG patterns 5ah, 5ai, 5ak and the magnetizing pattern 17j overlapped. In comparison with the case, the stronger magnetic field of the magnetized pattern 17j and the FG pattern 5aj Is longer than the other FG patterns 5ah, 5ai, 5ak in the radial direction, the current is high. Will occur.

[0022]   An arrow indicating the rotation cycle Tf shown as the input waveform of the filter 30 shown in FIG. The time points shown as high outputs at both ends of the mark are the magnetization pattern 17j and the FG pattern 5 This is the time when aj overlaps vertically. The rotation cycle Tf is determined by the limiter 31 using the FG sensor. Generation of a rectangular wave to a value that only the FG outputs 5a at both ends of the rotation cycle Tf act among the outputs of 5 If the reference is set, it is obtained as the output cycle of the limiter 31, The output is the same information as the PG output 18. The rectangular output wave generation reference is the broken line in FIG. It is L shown by. Further, the 1FG cycle T is set to a value equal to or less than a fixed value as the amplitude adjuster 32. Using an amplification element with a gain that generates a constant output for the input above, The FG cycle T can be fixed and handled as the same information as the conventional FG output 24. Becomes

[0023]   In the above embodiment, the area of the magnetizing pattern 17j is set to the other magnetizing pattern 17h, 17i and 17k, the magnetizing strength of the magnetizing pattern 17j is set to another magnetizing pattern. Even if it is stronger than the turns 17h, 17i, and 17k, the same effect as the above embodiment is obtained. Play.

[0024]   5 and 6 are a plan view and an FG pattern according to another embodiment of the present invention. And its FG output waveform. 5 (a) and 5 (b) are shown above the FG sensor 5. The top view which piled up the FG magnet 10 is shown, 17m is one magnetization pattern. The magnetizing notch 5a with the broken line showing the ideal state m is a magnetizing notch showing the FG pattern state in which the FG pattern is cut by one pitch. . Further, in FIG. 6, Ta is the magnetizing notch 17m and the FG notch 5a shown in FIG. 5 (a). FG output when m is vertically overlapped, and Tb is the magnetizing notch 1 shown in FIG. 5B. This is the output when the 7 m and the FG cutout 5 am do not vertically overlap.   In FIG. 5A, the FG notch 5am and the magnetizing notch 17m overlap each other, and The magnetizing pattern does not generate current in only one place. In addition, in FIG. No electric current is generated at two positions, a position with 5 am and a position with a magnetizing notch 17 m. The current in FIG. 5A is larger than the current in FIG. 5B, and the maximum value of the FG output is shown in FIG. FG outputs Ta and Tb shown in FIG.

[0025]   In addition, when the FG notch 5am and the magnetizing notch 17m do not overlap with each other, all are shown in FIG. As in (b), the current is at the position with the FG cutout 5am and the position with the magnetization cutout 17m. Since no current is generated at two locations, the value becomes equal to the value of the FG output Tb. Of FIG. L indicates the same rectangular wave generation reference as shown in FIG.

[0026]   FIG. 6 shows a modification of the filter 30 described above. As shown in, even when the FG output 5b becomes smaller for each rotation cycle Tf, the FG output 2 4 and PG output 18 are obtained. In addition, the FG output that decreases with each rotation output Tf 5b is obtained according to the embodiment shown in FIG.   In FIG. 6, 33 is the next input signal after a certain time has elapsed from the rise of one input signal. If there is no signal, a mono-multi circuit that outputs one square wave, Tm is this mono-multi circuit The time from the rise of one input signal of 33 to the output of 1 33 1FG period T <Tm This is the observation time selected for. Other configurations are the same as in FIG. Minutes are given the same reference numerals, and their description is omitted.

[0027]   8 and 9 are a plan view and an FG pattern according to another embodiment of the present invention. And its FG output waveform. 8A and 8B show the FG sensor 5 above. The top view which piled up the FG magnet 10 is shown, 17l is a magnetization pattern. In Fig. 9, Pa is shown in Fig. 8 (a). The FG output when the large magnetized part 17l and the FG cutout 5am overlap vertically, Pc is the figure FG output in a state where the large magnetized portion 171 and the FG cutout 5am shown in FIG. As shown in FIG. 8B, the force and Pb are larger than those in FIG. The FG output is shown at the time when a half pitch of 5 mm is shifted.

[0028]   In the case of the embodiment shown in FIG. 8 and FIG. 9, in the case of FIG. There is a difference in FG output 5b due to the difference in magnetic field strength between the magnetic portion 17l and other FG patterns. Occur. As shown in FIG. 9, the FG output Pa has a small value only in the case of FIG. However, in the overlapping of the other magnetization pattern and the FG pattern, as shown in FIG. 8 (c). The FG output Pc corresponding to the above case is output. The FG output 5a in FIG. 8C is shown in FIG. If it is input to the filter 30 shown in FIG. When Pa is 0, the output is 0, and when FG output is Pc, it is converted as output. The rectangular wave is synthesized and output by the multi-circuit 33 only in the case of the FG output Pa. The information is the same as the output 18. The other is a constant amplitude, That is, the same information as that of the FG output 24 is used as a fixed-cycle waveform.

[0029]   In addition, in the embodiment shown in FIGS. 5 and 6, one location of the magnetization pattern is a radial direction. It was magnetized for a long time, and the FG pattern was cut out, but one part of the magnetization pattern was cut out. Then, the FG pattern at one location is radially aligned with the FG pattern 5aj in FIG. Even if the G output 5b is increased, the same output as in FIG. 8C is obtained, and the same effect is obtained. To do.

[0030]   10 and 11 show an FG pattern of another embodiment of the present invention. The top view and its FG output waveform are shown. In FIG. 10, the magnetizing notch 17m and another FG The FG pattern 5aj, which is longer than the pattern 5a in the radial direction, overlaps in the vertical direction. In 0 (b), the magnetizing notch 17m and the other FG patterns 5a have the same size and are arranged in the radial direction. When the FG patterns 5a whose length is shorter than that of the FG patterns 5aj are overlapped, Show. In FIG. 11, Pb is the maximum value of the FG output of FIG. The maximum value of FG output of (b) is shown.

[0031]   In the case of the embodiment shown in FIG. 10 and FIG. In both cases, the FG output 5b for one pitch of the FG pattern 5a is not output. Yes. The output FG outputs 5b are all the same FG pattern in FIG. 10 (a). Although the FG pattern 5a is shorter in the radial direction than the pattern 5aj, in FIG. The FG pattern 5a for one pitch is the FG pattern 5aj. Therefore, FIG. In the case of 0 (a), the FG output becomes Pe as shown in FIG. 11, and in the case of FIG. 10 (b). It becomes larger than Pd which is the combined FG output. The waveform of FIG. 11 is the same as that of FIG. The PG output 18 and FG by the filter 30 shown in FIG. Converted to output 24.

[0032]

[Effect of device]

  As described above, according to the present invention, by the FG sensor and the FG magnet, Since the PG sensor and the PG magnet can be used together, It is possible to reduce the number of parts and reduce the size. Has the effect.

[Submission date] January 10, 1992

[Procedure Amendment 1]

[Document name to be amended] Statement

[Correction target item name] 0004

[Correction method] Change

[Correction content]

14 to 19 show a specific configuration example of a conventional rotation control device. And have your 14, 12 in the lower cylinder which is located below the rotary cylinder 1 and supports the rotating cylinder 1 rotatably by a shaft 13 and bearing 14. Reference numeral 15 is a rotor made of a permanent magnet fixed to the rotary cylinder 1, and 16 is a stator having a stator coil fixed to the lower cylinder 12.

[Procedure Amendment 2]

[Document name to be amended] Statement

[Name of item to be corrected] 0024

[Correction method] Change

[Correction content]

FIG. 5 and FIG. 6 show a plan view of an FG pattern and its FG output waveform in another embodiment of the present invention. 5A and 5B are plan views in which the FG magnet 10 is superposed above the FG sensor 5, and 17m is a broken line showing a position where one magnetization pattern is cut off, which should be the original state. The magnetizing notches 5a m shown together indicate magnetizing notches showing the FG pattern state in which the FG pattern is cut by one pitch. Further, in FIG. 6, Ta represents the FG output at the time when the magnetizing notch 17m and the FG notch 5am shown in FIG. And the FG notch 5am do not overlap vertically. In FIG. 5A, the FG notch 5am and the magnetizing notch 17m overlap each other, and the FG pattern and the magnetizing pattern do not generate current at only one place. Further, in FIG. 5 (b), no current is generated at two positions, the position with the FG cutout 5am and the position with the magnetizing cutout 17m. Current of FIG. 5 (a), the maximum value of the current from the large, FG output (b) is shown as an FG output T a shown in FIG.

[Procedure 3]

[Document name to be amended] Statement

[Correction target item name] 0026

[Correction method] Change

[Correction content]

FIG. 7 shows a modified example of the filter 30. According to the filter 30, as shown in FIG. 7 , even when the FG output 5b becomes smaller every rotation cycle Tf, the FG output 24 and PG output are reduced. Output 18 is obtained. The FG output 5b that decreases with each rotation output Tf is obtained by the embodiment shown in FIG. In FIG. 7 , reference numeral 33 denotes a mono-multi circuit that outputs one rectangular wave if a certain time has elapsed from the rise of one input signal and there is no next input signal, and Tm outputs from the rise of one input signal of this mono-multi circuit 33. Is the observation time selected for 1FG cycle T <Tm. Since the other configurations are the same as those in FIG. 2, the corresponding portions are denoted by the same reference numerals and the description thereof will be omitted.

[Procedure amendment 4]

[Document name to be amended] Statement

[Correction target item name] 0028

[Correction method] Change

[Correction content]

In the case of the embodiment shown in FIGS. 8 and 9, in FIGS. 8A and 8B, only the difference in the magnetic field strength between the large magnetized portion 17l and another FG pattern is used. A difference occurs in the FG output 5b. As shown in FIG. 9, the FG output P a takes a small value in the cases of FIGS. 8A and 8B, and when the other magnetic patterns and the FG pattern overlap with each other , the FG output P a is changed as shown in FIG. The FG output Pc corresponding to the case shown is output. If the FG output 5a of FIG. 8 (c) is input to the filter 30 shown in FIG. 7, one of them is converted by the limiter 31 as an output of 0 when the FG output Pa and an output of when the FG output Pc is present. The mono-multi circuit 33 synthesizes and outputs a rectangular wave only in the case of the FG output Pa, which is the same information as the PG output 18. On the other hand, the same information as that of the FG output 24 will be used thereafter as a constant amplitude, that is, a constant cycle waveform by the amplitude adjusting circuit 32.

[Brief description of drawings]

FIG. 1 is a block diagram showing a configuration of a rotation control device according to an embodiment of the present invention.

FIG. 2 is a block diagram showing a detailed configuration of the filter shown in FIG.

FIG. 3 is a side sectional view showing a specific configuration of a rotation control device.

FIG. 4 is a plan view showing an example of an FG pattern and a magnetization pattern of FIG.

FIG. 5 is a plan view of an FG pattern according to another embodiment of the present invention.

FIG. 6 is an FG output waveform diagram in the case of FIG.

FIG. 7 is a block diagram showing a configuration of a modified example of the filter of the present invention.

FIG. 8 is a plan view of an FG pattern according to another embodiment of the present invention.

9 is an FG output waveform in the case of FIG.

FIG. 10 is a plan view of an FG pattern according to another embodiment of the present invention.

11 is an FG output waveform in the case of FIG.

FIG. 12 is a block diagram showing a configuration of a conventional rotation control device.

FIG. 13 is a side view schematically showing a part of FIG.

FIG. 14 is a side sectional view showing a specific configuration of a conventional rotation control device.

FIG. 15 is an exploded perspective view illustrating the motor of FIG. 14 in detail.

16 is a perspective view showing the FG and PG magnets of FIG.

FIG. 17 is a plan view showing a state in which the FG magnet and the FG pattern of FIG. 15 overlap each other.

FIG. 18 is a block diagram showing a configuration of a conventional phase servo circuit.

FIG. 19 is a block diagram showing a configuration of a conventional speed servo circuit.

[Explanation of symbols]

1 rotating cylinder 4 motor 5 FG sensor 6 speed servo circuit 9 Motor control circuit 10 FG magnet 17 Magnetization pattern 5a FG pattern

Claims (2)

[Scope of utility model registration request] 1. A FG sensor that outputs a relative position of a rotary cylinder, an FG magnet that rotates integrally with the rotary cylinder, a motor that drives the rotary cylinder, and a FG magnet that is disposed so as to face the FG magnet. And a speed control circuit for converting the output of the FG sensor into an error output, and a motor control circuit for controlling the rotation speed of the motor according to the error output from the speed servo circuit. Of the plurality of magnetizing patterns is different from other magnetizing patterns, and the rotational speed control and the rotational phase control of the rotary cylinder are performed by the output of the FG sensor. . 2. The rotation control device according to claim 1, wherein a difference between a part of the plurality of magnetization patterns of the FG magnet and another magnetization pattern is a magnetization intensity.