KR100222473B1 - A driving circuit of head-drum with an impulse generation magnet and the controlling method therefor - Google Patents

Abstract

The present invention relates to a head drum motor driving circuit in which an impulse-generating magnet is magnetized and a control method thereof. Applying a current signal and detecting the binary magnetic signal generated by the relative action of the impulse magnet magnetized on the rotor detecting magnet of the rotor and the magnet coil of each phase applied, it detects the first of the head drum motor. The impulse signal detection step of detecting the switching position and the impulse signal and the detected waveform signal detected by the Hall sensor provided with only one stage after this impulse signal detection step are compared and judged to determine the current phase of the rotor. A drive sequence determination step of determining a next drive sequence based on the received signal, and a binary form detected during the impulse signal detection step. Comparing the cycle period of the pulse signal and outputting the rotational speed control signal of the head drum motor, and after the driving sequence determination step to drive the corresponding magnet coil in accordance with the next driving sequence determined and at the same time According to the rotational speed control signal, the rotational speed of the head drum motor is also controlled by the driving sequence and the rotational speed control execution step, which significantly reduces the manufacturing cost of the driving circuit.

Description

Head drum motor driving circuit with magnetized impulse magnet and its control method

The present invention relates to a head drum motor driving circuit in which an impulse-generating magnet is magnetized and a control method thereof. In particular, the first sequential N-stimulation in which a magnet is alternately magnetized within a certain period of the magnet frog detecting magnet magnetized on a rotational circumference of the rotor. Some of them do not magnetize the impulse magnets, but only the next few N-stimulus magnets are used to magnetize the impulse signals according to the inductance change from the impulse magnets through a single hall sensor in binary form. The present invention relates to a head drum motor driving circuit in which an impulse generating magnet magnetized to determine the switching position and rotational speed of a head drum motor by comparing the number and detection waveforms of the impulse signal of the head.

In general, the VLC system has a very small recording dimension of the video signal, a track width of about 0.2-0.02 mm, a recording wavelength of about several microns, and is recorded in the tape width direction. Therefore, it is necessary to stably control the rotation of the head drum motor so as not to change the time axis of the video signal as much as possible during recording. In addition, in order to maintain tracking of the video track, it is necessary to keep the head drum rotation and tape running state (speed and positional relationship) as in recording.

Then, referring to FIG. 1 of the conventional VDL head drum motor driving circuit, a plurality of Hall sensors detecting a relative rotational position of the rotor 70A of the head drum motor 70 at a predetermined angle ( 71A, 71B, amplifiers 72A, 72B connected to the output terminals of the Hall sensors 71A, 71B to amplify the detected head position detection signal to a predetermined level, and at one ends of the amplifiers 72A, 72B. It is composed of drive transistors 74A and 74B connected to the resistors R1 and R2 to apply driving voltages to the magnet coils 73A and 73B of the head drum motor 70, respectively.

The drive transistors 74A and 74B are each composed of NPN transistors. In addition, a bias power supply VCC is connected to the collector terminals of the driving transistors 74A and 74B.

In addition, a plurality of magnets 76 of the fsensor 75 for detecting the speed of the head drum motor 70 is magnetized on the rotation circumference of the rotor 70A, the magnets of the fsg sensor 75 A detection pattern 77 is formed at a position opposite to 76.

On the other hand, referring to the operation of the conventional head drum motor driving circuit having the above configuration, first, when the play mode or the recording mode signal is input to the V-CAL, a predetermined detection voltage is applied to the hall sensor 71A during the first driving. I will let you. Then, the Hall sensor 71A inputs a detection signal according to the rotational position detection voltage of the head drum motor 70, for example, a high signal to the amplifier 72A, whereby the amplifier 72A receives the input signal. After amplifying the high signal to a predetermined level, the resistor R1 is input to the base terminal of the driving transistor 74A. Then, the driving transistor 74A is driven in accordance with the high signal input to the base end to apply a bias voltage to the magnet coil 73A of the head drum motor 70. Therefore, the magnetic flux is generated in the magnet coil 73A of the head drum motor 70 to attract the magnetic pole of the rotor (not shown), so that the head drum motor 70 rotates by a predetermined rotation angle.

At this time, since the hall sensor 71B of the next phase does not perform the detection operation, the driving transistor 74B of the next phase is not driven.

However, when the rotor 70A of the head drum motor 70 rotates by a predetermined rotation angle during the process, the next phase Hall sensor 71B detects this. When the hall sensor 71B detects the magnetic signal of the rotor 70A, the amplifier 72B amplifies the input detection voltage to a predetermined level to pass the resistor R2 to the base end of the driving transistor 74B. Will be entered. Then, the driving transistor 74B is driven in accordance with the high signal input to the base end to apply a bias voltage to the magnet coil 73B of the head drum motor 70 as opposed to the magnet coil 73A. Therefore, the magnetic flux is generated in the magnet coil 73B of the next phase to push the magnetic pole of the rotor 70A, so that the head drum motor 70 rotates again by a predetermined rotation angle.

Then, as the above process is repeated, the Hall sensors 71A and 71B sequentially perform the detection operation, and thus driving power is sequentially applied to the magnet coils 73A and 73B of the head drum motor 70. The head drum motor 70 continues to rotate. At this time, the magnet 76 of the fsensor 75 mounted on the rotational circumference of the rotor 70A also rotates, so that the detection pattern 77 of the fsg sensor 75 is the magnet 76. The magnetic pulse signal is detected from the input to the microcomputer 78. Then, the microcomputer 78 determines the pulse signal of the input f sensor 75 to control the rotational speed of the currently driven head drum motor 70.

Accordingly, the head drum (not shown) which is interlocked with the head drum motor 70 is also rotated according to the set mode signal, so that the head mounted on the head drum plays back or records information from the video tape.

However, in the driving circuit of the conventional head drum motor as described above, since the Hall sensors 71A and 71B, which are components for detecting the rotational position of the head drum motor 70, are relatively expensive components, at least a plurality of motors must be installed. As a driving circuit, the manufacturing cost accordingly increased considerably, and in addition, since a specific specific space must be secured on the fixed printed circuit board to install the hall sensors 71A and 71B, there is a problem of limiting the space utilization of the system.

Accordingly, the present invention has been invented to solve the above-mentioned shortcomings, and the impulse magnet is magnetized in some of the first sequential N stimuli that are alternately magnetized within a certain section of the fG detection magnet magnetized on the rotational circumference of the rotor. The impulse magnet is magnetized to only a few N stimuli in the next sequence, and the impulse signal according to the inductance change is detected in binary form from the impulse magnet through one Hall sensor, and the number of impulse signals in binary form of each phase detected. The purpose of the present invention is to provide a head drum motor magnetized with an impulse generating magnet that determines the switching position and rotation speed of the head drum motor by comparing the detected waveforms, and a driving control method thereof.

Another object of the present invention is to detect the rotational position of the motor by using the impulse signal according to the inductance change detected from the impulse generating magnet magnetized on the rotational circumference of the rotor magnetized the frog detection magnet and to the detected switching signal Accordingly, the head drum motor can be driven precisely, thereby providing a head drum motor driving circuit in which an impulse magnet is magnetized, which significantly improves the reliability of the head drum motor.

The present invention for achieving the above object is a driving test applying step of applying a test current signal to the magnet coil of each phase in the initial stop state of the motor when the mode setting signal is set in the BC head drum motor; After the driving test application step, the binary magnetic signal generated by the relative action between the impulse magnet magnetized on the rotor's frog detection magnet and the magnet coil of each phase applied is detected to detect the head drum motor. The impulse signal detection step of detecting the first switching position and the binary pulse type impulse signal detected from the Hall sensor installed only after this impulse signal detection step are compared with the detected waveform signal to determine the current phase of the rotor. A drive sequence determination step of determining a next drive sequence based on the determined signal, and a binary form detected during the impulse signal detection step Comparing the period of the impulse signal and outputting the rotational speed control signal of the head drum motor, and driving the magnet coil according to the next driving sequence determined after the driving sequence determination step and at the same time According to the rotational speed control signal, the driving speed and rotational speed control execution step of controlling the rotational speed of the head drum motor is also characterized by consisting of.

1 is an explanatory diagram illustrating a driving circuit of a conventional head drum motor.

2 is an explanatory diagram illustrating a head drum motor driving circuit of the present invention;

3 is a structural diagram illustrating an embodiment in which an impulse magnet applied to the present invention is magnetized on an fG detection magnet;

4 is an explanatory diagram illustrating a head drum motor to which the present invention is applied;

5 is a flowchart of the present invention,

6 (a) is a waveform diagram showing the phase change according to the magnetic flux of the head drum motor,

(b) is the output waveform of the Hall sensor that detected the impulse magnet signal,

(c, e) is a waveform obtained by integrating the signal of FIG.

(d) is a waveform obtained by shifting the output waveform of FIG.

* Explanation of symbols for main parts of the drawings

1: Head 2: Head Drum

3: head drum motor 4: rotor

5: fG detection magnet 6: impulse magnet

7 Hall sensor 8 Amplifier

9: bit count unit 10: integral circuit unit

11: Comparator 12: Integrating Circuit

13: Zero Crossing 14: Rotating Magnet

15: drive control unit 16a-16c: magnet coil

17: switching driver 18: trigger

19: bit counter 20: stator

21: fixed printed circuit board 22: core

TR1-TR6: Drive Transistor

Hereinafter, the present invention will be described in detail with reference to the accompanying drawings.

As shown in Figs. 2 to 4, the driving circuit of the present invention includes a head drum motor 3 for rotating and driving the head drum 2 on which the head 1 of the V-Cal is mounted, and the head drum motor 3. FREQUENCY GENERATING detection magnetized on the rotational circumference of the rotor 4 in a single stage to detect a binary magnetic signal from an impulse magnet 6 installed in each N and S stimulus of the magnet 5. The hall sensor 7, the amplifier 8 for amplifying the binary type impulse signal detected from the hall sensor 7 to a predetermined level, and the binary type impulse signal output from the amplifier 8. A bit counting unit 9 for signal shaping to generate a counting signal, an integrating circuit unit 10 for integrating the impulse signal in binary form detected from the hall sensor 7, and an output waveform of the integrating circuit unit 10 A comparator 11 for shifting the signal by a certain period and the output signals of the comparator 11 Integral circuit part 12 for integrating and detecting speed signal by integrating square wave signal, and zero-crossing the output pulse signal of the integrator circuit part 12 to detect zero points. The counting signal according to the zero crossing unit 13, the zero point signals inputted from the zero crossing unit 13 and the impulse signal in the binary form inputted from the bit count unit 9 is judged and The drive control unit 15 determines the next drive sequence according to the current phase of the rotating magnet 14 and outputs the speed control signal of the head drum motor 3, and the next drive sequence control signal of the drive control unit 15. Therefore, the driving current is applied to the magnet coils 16a-16c and the switching driver 17 controls the rotational speed of the head drum motor 3 according to the speed control signal.

In addition, the bit count unit 9 includes a trigger 18 for waveform shaping the impulse signal detected from the hall sensor 7, and an example of a binary number for counting a waveform shaping the impulse signal through the trigger 18. It consists of a two-bit counter 19 for counting the pulse signal of the.

In the switching driver 3, drive transistors TR1-TR6 for applying a test pulse signal or a driving voltage for detecting the rotation position to the magnet coils 16a-16c of each phase are connected in a constant connection method. According to the "Y" connection, the magnet coils 16a-16c are connected to the respective coils. In this case, the bias voltage VCC is connected to the collector terminals of the driving transistors TR1, TR3, and TR5, and the driving transistors TR1 and TR3. , Magnet coils 16a-16c of each phase are connected to a common connection point at which the emitter terminal of TR5 and the collector terminal of the driving transistors TR2, TR4 and TR6 are connected, respectively, and the driving transistor TR1 Each base end of -TR6 is connected to a drive control unit 15.

Here, the impulse magnet 6 is selectively magnetized at a predetermined interval within each N, S stimulation of the fG detection magnet 5 magnetized on the rotational circumference of the rotor 4, for example, the fG detection magnet ( 5) The impulse magnet (6) is magnetized to the S-magnetized magnet within a certain period of time, and the magnet is repeatedly magnetized in the form of magnets "0" first, then "1" and then "2". At the same time, the N stimuli alternately magnetized within a certain period of the S stimulus and the F-detection magnet 5 do not magnetize the impulse magnet 6 in the first three N stimuli, but the next N stimulus. Only three of them will magnetize the impulse magnet. Therefore, when the magnetic signal of the magnetized impulse magnet 6 is detected, the binary form of the value "0, 0-0, 1-0, 2-1, 0-1, 1-1, 2-0, 0" Will be detected.

In addition, the head drum motor 3 is composed of a rotor 4 and a stator 20 as shown in Figure 4, wherein the stator 20 is a fixed print installed in the lower portion of the head drum (2) The substrate 21 is provided in the form of a core 22 wound with magnet coils 16a-16c. The stator 20 has a predetermined gap in the opposite position of the stator 20 and has N and S poles on its inner surface. The rotor 4 in which the rotating magnet 14 is magnetized is installed.

Next, the operation and effects of the present invention having the above configuration will be described.

First, as shown in FIG. 5, the present invention proceeds from the initial state S1 to the mode signal setting determination step S2 to determine whether the current mode signal is set. As a result of the determination during the mode signal setting determination step S2, if the mode setting signal is not set, for example, the playback mode or the recording mode signal is returned, the process returns to the previous step S1 to repeat the loop. However, if the mode setting signal is set as a result of judging during the mode signal setting determination step (S2), the drive test application step (S3) proceeds to the test current to the magnet coil of each phase in the initial stop state of the motor. Apply a signal. After the driving test application step (S3), the process proceeds to the impulse signal detection step (S4) to detect the detection current signal according to the inductance change from the magnet coil of each phase applied to determine the initial switching position of the head drum motor. Will be detected.

That is, when the mode signal is set, the driving controller 15 drives the head drum motor 3 at a rotation speed suitable for the set mode signal, and at this time, the driving current to detect the rotation position of the head drum motor 3. The signals are sequentially passed through the magnet coils 16a-16c of each phase.

For example, the driving controller 15 turns on the driving transistor TR1 and the driving transistor TR4 when the phase is "u" through the switching driver 17 so that only the opposite current flows in the same magnet coil 16a. The driving transistor TR3 and the driving transistor TR2 are also turned on. In the case of the "v" phase, the driving transistor TR3 and the driving transistor TR6 of the switching driver 17 are turned on, and the driving transistor TR5 and the reverse current flow in the same magnet coil 16b. The driving transistor TR4 is also turned on. Further, in the case of the "w" phase, the driving transistor TR5 and the driving transistor TR2 of the switching driver 17 are turned on and the driving transistor TR1 and the current are reversed so that only the opposite direction flows through the same magnet coil 16c. The driving transistor TR6 is turned on. Then, the corresponding driving transistors TR1-TR6 of the switching driver 3 are driven in accordance with the driving control signal input to the base end to apply a bias voltage to the corresponding magnet coils 16a-16c of the head drum motor 3. Let's do it. Therefore, magnetic flux is generated in the corresponding magnet coils 16a-16c of the head drum motor 3 to attract the rotating magnet 14 of the rotor 4, so that the head drum motor 3 rotates by a predetermined rotation angle. . Therefore, as the rotor 4 of the head drum motor 3 moves relative to the stator 20, the inductance value of the stator 20 also changes as shown in FIG. 6A. In addition, the hall sensor 7 provided with only one stage on the fixed printed circuit board 21 detects a magnetic signal according to the changed inductance value, and this hall sensor 7 rotates the rotor 4. Magnetic signals generated from the impulse magnets 6 installed on the N and S magnetic poles of the fG detection magnets 5 arranged on the circumference are detected in the form of pulses as shown in FIG.

On the other hand, after the impulse signal detection step (S4) proceeds to the drive sequence determination step (S5) and compares the impulse signal and the detected waveform signal detected from the Hall sensor installed only one stage to determine the current phase of the rotor and determine the Based on the signal, the next driving sequence is determined. At the same time as the above operation, the number of pulses of the waveform signal is compared and the rotation speed control signal of the head drum motor is also output. After the driving sequence determination step S5, the driving sequence determination completion step S6 is performed to determine whether the driving sequence determination and calculation operation of the rotational speed control signal of the motor are completed. In addition, if it is determined during the driving sequence determination completion step (S6), if the current driving sequence determination and the calculation operation of the rotational speed control signal of the motor are not completed, the process returns to the previous step (S5) and repeats the loop. However, when the driving sequence determination and the calculation operation of the rotational speed control signal of the motor have been completed as a result of the determination during the driving sequence determination completion determination step (S6), the process proceeds to the driving sequence and the rotational speed control execution step (S7). The magnet coil is driven according to the determined driving sequence, and the rotation speed of the head drum motor is also controlled at a constant speed according to the rotation speed control signal of the motor calculated at the same time.

That is, when the impulse signal is detected in binary form by the Hall sensor 7 as shown in (b) of FIG. 6, for example, "0, 0-0, 1-0, 2-1, 0-1". When the magnetic signal is detected in binary form with a value of 1, 1, 2-0, 0 ", etc., the detected binary type impulse signal is input to the amplifier 8 and amplified to a predetermined level. The trigger 18 and the integrating circuit 19 of the counting unit 9 are respectively input. Then, the trigger 18 forms a signal of the input binary impulse signal and inputs it to the bit counter 19, for example, the 2-bit counter 19. Accordingly, the 2-bit counter 19 counts according to the input impulse signal and inputs the counted signal to the drive control unit 15. For example, the impulse magnet 6 on the fG detection magnet 5 is input. In the case where two magnets are magnetized, two pulse signals are detected through the hall sensor 7, so that the two-bit counter 17 inputs an output signal corresponding to the "2" bit to the driving controller 15.

On the other hand, the detection signal of the Hall sensor 7 input to the integrating circuit unit 10 at the same time as the operation is integrated by the integrating circuit unit 10 as shown in (c) of FIG. Accordingly, the comparator 11 shifts the input waveform of the input integrated circuit unit 10 by a predetermined period as shown in FIG. 6 (d) and inputs it to the integrated circuit unit 12. In the integrating circuit section 12, the output signal of the input comparator 11 is integrated as shown in Fig. 6E, converted into a signal of a predetermined type, and then input to the zero crossing section 13. . Then, the zero crossing unit 13 zero-crosses the input signal of the integrated circuit unit 12 and inputs the detected zero point signals to the drive control unit 15.

Accordingly, the drive control unit 15 uses the binary number impulse number input through the 2-bit counter 19 between the zero points corresponding to the phase of the rotor 4 input from the zero crossing unit 13. The phase of the rotor 4 currently operating is judged by comparing and determining how many are present. Based on the determined phase of the rotor 4, the sequence of the magnet coils 16a-16c to be driven next is determined. For example, in the last driving sequence of the magnet coil 16a on "u", the impulse signal in binary form is defined so that "0, 2" value is detected, and the magnet coil 16b on "v" which is the next driving sequence is If the impulse signal is defined such that "1, 0" is detected and the current impulse signal is detected as "0, 2", the driving controller 15 may change the phase of the rotation magnet 14 of the rotor 4 to ". Recognizing that it corresponds to the magnet coil 16a on u ", the magnet coil 16b of" v "is determined as the next drive sequence. Then, the driving controller 15 drives the head drum motor 3 by applying a driving current to the corresponding magnet coil 16b through the switching driver 17 in accordance with the determined next driving sequence.

At the same time, the driving control unit 15 performs the zero point signals input from the zero crossing unit 13 for a predetermined period, for example, as shown in FIG. 6E while the head drum motor 3 is rotated once. By comparing the number of detected zero point signals, the current rotation speed of the head drum motor 3 is recognized and an appropriate speed control signal is applied to the switching driver 17. For example, the detected zero point signal is detected. When the number of pieces is less than the set number of mode signals, the driving voltage applied to the magnet coils 16a-16c is increased through the switching driver 17 to keep the speed of the motor 3 constant.

As described above, in the present invention, the first N-magnets of the first sequence alternately magnetized within a certain range of the magnets of the fG magnet magnetized on the rotational circumference of the rotor, do not magnetize the impulse magnet, but only the next N-magnets of the next sequence. Magnetizing the impulse magnet and detecting the impulse signal according to the inductance change from the impulse magnet in the binary form through one Hall sensor, and comparing the number and the detected waveform of the impulse signal in the binary form of each phase of the head drum motor The switching position and rotation speed are determined. In addition, by detecting the rotational position of the motor using the impulse signal according to the inductance change detected from the impulse generating magnet magnetized on the rotating circumference of the rotor magnetized by the fG detection magnet, the head drum motor is precisely detected according to the detected switching signal. As a result, the reliability of the head drum motor can be significantly improved.

Claims (3)

In the driving circuit of a head drum motor provided with a switching driver 17 for applying a driving current to the magnet coils 16a-16c of the BC head drum motor 3, A hall sensor (7) having a singular number for detecting a magnetic signal in binary form from an impulse magnet (6) provided in each of the N and S magnetic poles of the head drum motor (3) and the edge detecting magnet (5); An amplifier 8 for amplifying the binary impulse signal detected from (7) to a predetermined level, and a bit count unit for generating a counting signal by signal shaping the impulse signal output from the amplifier 8; (9), an integrating circuit portion 10 for integrating the impulse signal in binary form detected from the hall sensor 7, and a comparator 11 for shifting the output waveform of the integrating circuit portion 10 by a predetermined period; Integrating the output signals of the comparator 11 again to convert the output signal into a predetermined form for speed signal detection, and zero-crossing the output pulse signal of the integrating circuit unit 12 to detect zero points. With the zero crossing section 13 and this zero crossing section 13 The next driving sequence according to the current phase of the rotating magnet 14 of the rotor 4 is determined by determining the counting signal according to the zero point signals inputted from the input unit and the impulse signal inputted from the bit count unit 9. And a drive controller (15) for determining and outputting the speed control signal of the head drum motor (3). The impulse magnet (6) is magnetized in a sequential manner of increasing the number of S-poles magnetized in a predetermined period of the F-detection magnet (5), and alternately magnetized to the S-poles. 3. The head drum motor driving circuit in which the impulse-generating magnet is magnetized, wherein the N-poles are selectively magnetized to only three N-poles in the next sequence without magnetizing the impulse magnet (6) in the first three N-poles. When the mode setting signal is set for the V-Cal head drum motor, the drive test applying step of applying a test current signal to the magnet coil of each phase in the initial stop state of the motor, and the edge detection of the rotor after this driving test applying step An impulse signal detection step of detecting the initial switching position of the head drum motor by detecting a binary magnetic signal generated by the relative action of the impulse magnet magnetized on the magnet and the magnet coil of each phase applied; After the impulse signal detection step, the binary-type impulse signal detected by the Hall sensor installed in the single stage is compared with the detected waveform signal to determine the current rotor phase and determine the next driving sequence based on the determined signal. Comparing the driving sequence determination step and the period of the impulse signal in binary form detected during the impulse signal detection step A motor rotational speed calculating step of outputting a rotational speed control signal of the motor, and driving the magnet coil according to the next driving sequence determined after the driving sequence determining step, and at the same time of the head drum motor according to the rotational speed control signal of the motor A control method of a head drum motor magnetized by an impulse generating magnet, characterized in that it comprises a driving sequence for controlling the rotational speed at a constant speed and an execution step of the rotational speed control.

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