JPH0845008A - Recording and reproducing device - Google Patents

Abstract

PURPOSE:To highly speed up a rising time of a recording current even when the inductance of a coil of a magnetic head is large by changing plural different voltages based on a recording information signal and supplying it to the magnetic head. CONSTITUTION:Upon the rise of the recording information signal (a) which is generated by a recording information generating circuit 2, a high voltage VH of a power supply means 5 is supplied to the coil of the magnetic head 3 connected with a switching element 15 of a current supply means 4 during a time from rising the signal (a) to the time set by a changeover time setting circuit 10 of a power changeover means 6, and subsequently, a low voltage VL is supplied. Then, upon the fall of the signal (a), a high voltage VH is supplied to a coil of the head 3 connected with a switching element 16 until the time set by the circuit 10 after the fall of the signal (a), and subsequently, a low voltage VL is supplied. Consequently, the rising time of the recording current can be speeded up at the time of inverting the current in its positive and negative to be supplied to the head 3, and information can satisfactorily be performed by the head 3.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a recording / reproducing apparatus for recording information on a recording medium using magnetism.

[0002]

2. Description of the Related Art In recent years, a recording / reproducing apparatus using a magnetic recording medium has been used in various fields such as audiovisual and computer applications, and drives a magnetic head for recording information on the magnetic recording medium and a magnetic head. A variety of writing circuits are also used to record recording information on a recording medium. For example, in order to drive a magnetic head composed of a bifilar winding coil, many recording / reproducing devices such as a floppy disk device using a bipolar drive system have been proposed.

An example of the above-mentioned conventional recording / reproducing apparatus will be described below with reference to the drawings. FIG. 7 is a block diagram showing a magnetic head drive circuit of a conventional recording / reproducing apparatus.
In FIG. 7, 101 is a magnetic head formed by bifilar winding. Reference numeral 102 denotes a recording information generation circuit that generates information to be recorded in the magnetic recording area of the recording medium. 103
Is a power supply with a single voltage that supplies power to the magnetic head drive circuit. 104 is a current for driving the magnetic head,
That is, it is a current setting resistor that sets a recording current for recording information on the recording medium. Reference numeral 105 denotes an inverting element that inverts the recording information signal generated by the recording information generation circuit 102. Reference numerals 106 and 107 denote switching elements that switch the coils of the magnetic head 101 that supplies current.

The operation of the magnetic head drive circuit of the recording / reproducing apparatus configured as described above will be described below. The recording information signal generated by the recording information generation circuit 102 is input to the switching element 107, and the recording information signal inverted by the inversion element 105 is input to the switching element 106. The switching elements 106 and 107 are alternately turned on according to the recording information signal. A current set by the current setting resistor 104 flows on the coil side of the magnetic head 101 connected to the switching element that is switched on. Since the two coils of the magnetic head 101 have opposite polarities, a magnetic field whose polarity changes depending on which coil the current flows through is generated. With the above configuration, it is possible to record the record information on the recording medium.

[0005]

However, in the above-mentioned structure, since the coil of the magnetic head has an inductance, the rising time of the recording current is delayed,
There is a problem that the recording characteristics are deteriorated. Further, in the recording / reproducing apparatus that requires a high magnetomotive force, there is a problem that the inductance of the coil of the magnetic head becomes large, the rise time of the recording current is delayed, and the recording characteristics are deteriorated.

In view of the above problems, the present invention makes it possible to shorten the rise time of the recording current even when the inductance of the coil of the magnetic head is large, and to write information well by the magnetic head. It is intended to provide a reproducing device.

[0007]

In order to solve the above problems, a recording / reproducing apparatus of the present invention comprises a current supply means for supplying a current to a magnetic head, and a power supply means having at least two different voltages. Power supply switching means for switching the voltage of the power supply means based on the record information from the record information generation circuit and supplying the power to the current supply means.

[0008]

According to the present invention, with the above-described configuration, even if the inductance of the coil of the magnetic head is large, when the positive / negative of the current supplied to the magnetic head is reversed, a high voltage is supplied to the current supply means. By switching the voltage of the means, the rise time of the recording current can be shortened, and information can be written well by the magnetic head.

[0009]

【Example】

(Embodiment 1) Hereinafter, a recording / reproducing apparatus according to a first embodiment of the present invention will be described with reference to the drawings. FIG. 1 is a block diagram showing the configuration of a magnetic head drive circuit section of a recording / reproducing apparatus according to the first embodiment of the present invention. In FIG. 1, reference numeral 1 is a recording medium having at least a magnetic recording area. Reference numeral 2 is a recording information generation circuit that generates information to be recorded. A magnetic head 3 records the recording information generated by the recording information generating circuit 2 on the recording medium 1. Reference numeral 4 is a current supply means for supplying a current to the magnetic head 3. Reference numeral 5 is a power supply means provided with two different voltages. Reference numeral 6 is a power switching means for switching the voltage of the power supply means 5 to supply power to the current supply means 4.

FIG. 2 is a circuit diagram showing the structure of the magnetic head drive circuit portion of the recording / reproducing apparatus in the first embodiment of the present invention. In FIG. 2, 1 is a recording medium, 2 is a recording information generation circuit, 3 is a magnetic head composed of a bifilar winding coil, 4 is a current supply means, and 5 is a high voltage V _H and low. Reference numeral 6 is a power supply means having a voltage V _L , and 6 is a power switching means. a is a recording information signal generated by the recording information generating circuit 2. Reference numeral 7 is a mono-multi that outputs one pulse in synchronization with the rising edge of the recording information signal a, and b is an output signal of the mono-multi 7. Reference numeral 8 is a mono-multi that outputs one pulse in synchronization with the falling edge of the recording information signal a, and c is an output signal of the mono-multi 8. Reference numeral 9 is an input N for outputting a signal b and a signal c and outputting an L level signal when one of them is at an H level.
It is an OR gate. d is the output signal of the NOR gate 9. Reference numeral 10 denotes a switching time setting circuit that outputs one pulse of a predetermined time width in synchronization with the rising edge of the signal d and sets the time for supplying the high voltage V _H of the power supply means 5 to the current supply means 4. , E are switching time setting circuits 1
0 output signal. Reference numeral 11 is a switching element for supplying the high voltage V _H of the power supply means 5 to the current supply means 4. 12 is a current setting resistor for setting a predetermined current at a low voltage V _L of the power supply means 5, 13 high voltage V _H of the power supply means 5 to a low voltage V _L of the current setting resistor 12 and the power supply unit 5 It is a diode to prevent accidental supply. f is a voltage signal supplied to the current supply means 4 by the power switching means 6. 14
Is an inverting element that inverts the signal a. Switching elements 15 and 16 switch the coils of the magnetic head 3 that supplies current.

FIG. 3 is a timing chart for explaining the operation of the magnetic head drive circuit section of the recording / reproducing apparatus in the first embodiment of the present invention. In FIG. 3, S0 is the signal a, S1 is the signal b, S2 is the signal c, and S3
Is a signal d, S4 is a signal e, and V is a signal f. I is a current flowing through the magnetic head 3, that is, a recording current.

The operation of the recording / reproducing apparatus configured as described above will be described below with reference to FIGS. 1, 2 and 3. First, the voltage signal f in which the power switching means 6 switches the voltage of the power supply means 5 based on the information recording signal a.
The operation of supplying the magnetic field to the magnetic head 3 and the current supply means 4 will be described. The recording information signal a generated by the recording information generation circuit 2 is input to the mono-multi 7 and the mono-multi 8 of the power switching means 6. Next, the monomulti 7 is a signal b which generates a pulse in synchronization with the rising edge of the signal a, and the monomulti 8 is a signal b which generates a pulse in synchronization with the falling edge of the signal a.
produces c. The temporal change of each signal in this process is shown in S0, S1, and S2 of the timing chart of FIG. Next, the pulse signals b and c are input to the NOR gate 9 and NOR
The gate 9 generates a signal d that generates a pulse in synchronization with the rising edge and the falling edge of the recording information signal a. The temporal change of each signal in this process is shown in S0 and S3 of the timing chart of FIG. Next, the signal d generated by the NOR gate 9 is supplied to the switching time setting circuit 10
The switching time setting circuit 10 generates a signal e for generating a pulse having a predetermined time width in synchronization with the rising edge and the falling edge of the recording information signal a. The temporal change of each signal in this process is shown in S0 and S4 of the timing chart of FIG. The predetermined time is the time required to reach the predetermined current when the positive / negative of the current supplied to the head is reversed. Next, the signal e generated by the switching time setting circuit 10 is input to the switching element 11, and the switching element 11 is turned on when the signal e rises and turned off when it falls. When the switching element 11 is turned on, the high voltage V _H of the power supply means 5 is supplied to the magnetic head 3 and the current supply means 4. When the switching element 11 is turned off, the low voltage _VL of the power supply means 5 is supplied to the magnetic head 3 and the current supply means 4, and the predetermined current is set by the current setting resistor 12 at the low voltage _VL . That is, the power switching means 6 supplies the voltage signal f, which is the voltage of the power supply means 5 switched based on the information recording signal a, to the magnetic head 3 and the current supply means 4. The temporal change of each signal in this process is shown in S4 and V of the timing chart of FIG.

Next, the operation of the current flowing through the magnetic head 3 will be described. First, the recording information signal a generated by the recording information generating circuit 2 is input to the switching element 15 and the inverting element 14 of the current supply means 4. Inversion element 14
Outputs the recording information signal a to the switching element 16 as an inverted recording information signal. The switching elements 15 and 16 are alternately turned on according to the recording information signal. That is, the switching element 15 is switched on and the switching element 16 is switched off at the rising of the recording information signal a, and the switching element 15 is switched off and the switching element 16 is switched on at the falling of the recording information signal a. It becomes a state.

The two operations described above will be described collectively. At the rising edge of the recording information signal a, the switching element 1
The coil of the magnetic head 3 connected to
After the rise, the high voltage V _H of the power supply means 5 is supplied until the time set by the switching time setting circuit 10 reaches a predetermined current, and then the low voltage V _L of the power supply means 5 is kept until the fall of the signal a. It is supplied and a predetermined current is supplied. Further, in the coil of the magnetic head 3 connected to the switching element 16 at the fall of the recording information signal a, after the fall of the signal a, until the time set by the switching time setting circuit 10, the power supply means 5 operates. A high voltage V _H is supplied to reach the predetermined current, after which the signal a
The low voltage V _L of the power supply means 5 is supplied and a predetermined current is supplied until the rising of. Therefore, when the recording information signal a rises and falls, that is, when the polarity of the current supplied to the magnetic head 3 is reversed, the rise time of the current can be shortened. Further, since the two coils of the magnetic head 3 have opposite polarities, the magnetic head 3 generates a magnetic field whose polarity is changed depending on which coil the current flows, and records the recorded information on the recording medium. be able to. Figure 3 shows the temporal changes of each signal in this process.
It is shown in S0, V, and I of the timing chart.

As described above, according to the present embodiment, the current supply means 4 for supplying a current to the magnetic head 3, the power supply means 5 having two different voltages, and the record information from the record information generating circuit 2 are provided. And the power supply switching means 6 for supplying power to the current supply means 4 by switching the voltage of the power supply means 5 on the basis of the above. Therefore, even if the inductance of the coil of the magnetic head 3 is large, it is supplied to the magnetic head 3. By switching the voltage of the power supply means 5 so that a high voltage is supplied to the current supply means 4 when reversing the positive / negative of the current, the rise time of the recording current can be shortened and the information of the magnetic head 3 can be changed. Writing can be performed well. Further, after the recording current reaches the predetermined current, the power consumption can be reduced by switching the voltage of the power supply means so that the low voltage is supplied to the current supply means.

(Embodiment 2) Next, a second embodiment of the present invention will be described with reference to the drawings. FIG. 4 is a circuit diagram showing the configuration of the magnetic head drive circuit section of the recording / reproducing apparatus showing the second embodiment of the present invention. In FIG. 4, 1 is a recording medium having a magnetic recording area, 2 is a recording information generating circuit, 3 is a magnetic head constituted by bifilar winding, 4 is a current supply means, and 5 is power supply. And 6 is a power switching means. Reference numeral a is a recording information signal, reference numeral 7 is a mono-multi which outputs one pulse in synchronization with a rising edge of the recording information signal a, and reference numeral b is an output signal of the mono-multi 7. Reference numeral 8 is a mono-multi that outputs one pulse in synchronization with the falling edge of the recording information signal a, and c is an output signal of the mono-multi 8. Reference numeral 9 is a NOR gate having signals b and c as inputs. d is the output signal of the NOR gate. Reference numeral 11 is a switching element for supplying the high voltage V _H of the power supply means 5 to the current supply means 4. 12 is a current setting resistor for setting a predetermined current at a low voltage V _L of the power supply means 5, 13 high voltage V _H of the power supply means 5 to a low voltage V _L of the current setting resistor 12 and the power supply unit 5 It is a diode to prevent accidental supply. f is a voltage signal supplied to the current supply means 4 by the power switching means 6. 1
Reference numeral 4 is an inverting element that inverts the signal a. Switching elements 15 and 16 switch the coils of the magnetic head 3 that supplies current. The above is the same as the configuration of FIG.

The present embodiment differs from the first embodiment shown in FIG. 2 in that the current detection resistor 17 is provided in the current supply means 4 for detecting the current supplied to the magnetic head 3 and the switching time. Switching signal generation circuit 1 instead of setting circuit 10
8 is provided, and it is detected that the current detected by the current detection resistor 17 has reached a predetermined current, and a low voltage is supplied to the magnetic head 3 so that the predetermined current is constantly supplied to the magnetic head 3. As described above, the switching signal generation circuit 18 generates a switching signal for turning on and off the switching element 11 that switches the voltage of the power supply means 5.

Regarding the operation of the recording / reproducing apparatus configured as described above, only the operation different from that of the first embodiment will be described. This embodiment is different from the first embodiment in that a switching element 11 for switching the voltage of the power supply means 5 by the power switching means 6 based on the information recording signal a.
Is an on / off switching operation. The signal d generated by the NOR gate 9 and the current detected by the current detection resistor 17 are input to the switching signal generation circuit 18. The switching signal generation circuit 18 turns on the switching element 11 at the rising edge of the signal d and, when detecting that a predetermined current is reached, generates the switching signal g for turning off the switching element 11 and outputs the switching signal to the switching element. Output to 11. The operation of switching the voltage of the power supply means depending on the ON and OFF states of the switching element 11 is the same as the operation described in the first embodiment.

As described above, according to this embodiment, the current supply means 4 for supplying a current to the magnetic head, the power supply means 5 having two different voltages, and the record information from the record information generating circuit 2 are provided. By detecting a predetermined current flowing through the magnetic head 3, the voltage of the power supply means 5 is switched to change the current supply means 4.
Since the electric power switching means 6 for supplying electric power to the magnetic head 3 is provided, even if the inductance of the coil of the magnetic head 3 is large, a high voltage is supplied to the current supply means 4 when inverting the positive / negative of the electric current supplied to the magnetic head 3. By switching the voltage of the power supply means 5 as described above, the rise time of the recording current can be shortened, and information can be written favorably by the magnetic head. Further, the power consumption can be reduced by switching the voltage of the power supply means 5 so that a low voltage is supplied to the current supply means 4 after the recording current reaches the predetermined current. Further, since the current flowing through the magnetic head 3 is detected, the voltage supplied to the magnetic head 3 and the current supply means 4 is switched to a low voltage when the predetermined current is reached, regardless of the specifications of the inductance of the magnetic head 3, and the efficiency is improved. Good power consumption.

In the first and second embodiments, the magnetic head 3 is composed of a bifilar winding coil, but the magnetic head 3 may be composed of a monofilar winding coil. However, the current supply means 4
As shown in FIG. 5, each of the switching elements 15 and 16 of FIG. 2 includes two switching elements 19 to 21 connected to both ends of the coil of the magnetic head 3 of the monofilar winding. One switching element 19, 2 connected to each end of the coil of the head 3A
1 shall be supplied with electric power.

Although the recording medium 1 has at least a magnetic recording area in the first and second embodiments, it may have at least an optically reproducible optical area and magnetic recording area. good. In the first and second embodiments, the recording medium 1 has at least a magnetic recording area. However, the recording medium 1 has a coercive force of 1600 Oersted or more, and the distance from the magnetic surface of the magnetic recording area to the magnetic head is large. May have 3 microns or more. FIG. 6 shows an example of the configuration of this type of recording medium. 1
A is a recording medium, 23 is a substrate of the recording medium, one side of the substrate 23 is provided with an optically reproducible optical region 26, and the other side of the substrate 23 is a magnetic medium having a coercive force of 1600 Oersted. The recording area 24 is provided, and the surface of the magnetic recording area 24 is provided with a protective layer 25 of 3 microns.
When the recording medium 1A having the structure shown in FIG. 6 is used in the recording / reproducing apparatus, a large magnetomotive force is required for recording, the number of windings of the coil of the magnetic head increases, and the inductance increases. When the inductance is further increased, the rising time of the recording current is further delayed and the recording characteristics are deteriorated. However, with the configuration of the present embodiment, the rising time of the recording current can be shortened and the writing of information by the magnetic head is performed. Can be performed satisfactorily.

[0022]

As described above, according to the present invention, the electric current supplying means for supplying the electric current to the magnetic head, the electric power supplying means having at least two different voltages, and the electric power based on the recording information from the recording information generating circuit are supplied. By providing the power switching means for switching the voltage of the supply means and supplying the electric power to the current supply means, even when the inductance of the coil of the magnetic head is large, a high voltage is applied when the positive / negative of the current supplied to the magnetic head is reversed. By switching the voltage of the power supply means so that the current is supplied to the current supply means, the rise time of the recording current can be shortened and information can be written well by the magnetic head. Further, after the recording current reaches the predetermined current, the power consumption can be reduced by switching the voltage of the power supply means so that the low voltage is supplied to the current supply means.

[Brief description of drawings]

FIG. 1 is a block diagram showing a configuration of a magnetic head drive circuit unit of a recording / reproducing apparatus according to a first embodiment of the present invention.

FIG. 2 is a circuit diagram showing a configuration of a magnetic head drive circuit unit of the recording / reproducing apparatus in the embodiment.

FIG. 3 is a timing chart for explaining the operation of the magnetic head drive circuit unit of the recording / reproducing apparatus in the embodiment.

FIG. 4 is a circuit diagram showing a configuration of a magnetic head drive circuit section of a recording / reproducing apparatus according to a second embodiment of the present invention.

FIG. 5 is a circuit diagram showing another configuration of the magnetic head and the current supply means of the magnetic head drive circuit section of the recording / reproducing apparatus in the embodiment of the present invention.

FIG. 6 is a cross-sectional view showing a configuration example of a recording medium of a recording / reproducing apparatus in an example of the present invention.

FIG. 7 is a circuit diagram showing a configuration of a magnetic head drive circuit section of a conventional recording / reproducing apparatus.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 recording medium 2 recording information generation circuit 3 magnetic head 4 current supply means 5 power supply means 6 power switching means 7 monomulti 8 monomulti 9 NOR gate 10 switching time setting circuit 11 switching element 12 current setting resistor 13 diode 14 inverting element 15 Switching element 16 Switching element 17 Current detection resistor 18 Switching signal generating circuit 19 Switching element 20 Switching element 21 Switching element 22 Switching element 23 Substrate 24 Magnetic recording area 25 Protective layer 26 Optical area a Recording information signal b Mono-multi 7 output signal c Output signal of mono-multi 8 d Output signal of NOR gate 9 e Output signal of switching time setting circuit 10 f Voltage signal g Switching signal

Claims (9)

[Claims] 1. A recording information generation circuit for generating information to be recorded in a magnetic recording area of a recording medium, a magnetic head for recording at least the recording information generated by the recording information generation circuit on the recording medium, and the magnetic head. Current supply means for supplying a current to the current supply means, power supply means for supplying power to the current supply means by providing at least two different voltages, and voltage of the power supply means based on the record information from the record information generating circuit. And a power switching means for supplying power to the current supply means. 2. The magnetic head is a bifilar winding in which the winding method of the coil is composed of two coils having different polarities, and the current supply means is two switching elements connected to one end of each of the two coils. 2. The recording / reproducing apparatus according to claim 1, further comprising: a power switching unit that supplies power to the other ends of the two coils. 3. The magnetic head is a monofilar winding in which a coil is formed by one coil, and the current supply means includes two switching elements connected to both ends of the coil, respectively, and power switching is performed. The recording / reproducing apparatus according to claim 1, wherein the means supplies electric power to each one switching element connected to both ends of the coil. 4. The power supply means is provided with two voltages, a high voltage and a low voltage, and the power switching means supplies a high voltage to the current supply means when inverting the positive / negative of the current supplied to the magnetic head. 4. The recording / reproducing apparatus according to claim 1, 2 or 3, wherein the voltage of the power supply means is switched to. 5. The power supply means comprises two voltages, a high voltage and a low voltage, and the power switching means supplies a high voltage to the current supply means for a certain period of time when inverting the positive / negative of the current supplied to the magnetic head. 5. The recording / reproducing apparatus according to claim 4, further comprising switching time setting means for setting a time for switching the voltage of the power supply means. 6. The power supply means is provided with two voltages, a high voltage and a low voltage, and the power switching means has means for detecting that the positive / negative of the current supplied to the magnetic head is inverted to reach a predetermined current. And, after reaching a predetermined current, generates a switching signal for switching the voltage of the power means so that a low voltage is supplied to the current supply means so as to constantly supply the predetermined current to the magnetic head. 5. The recording / reproducing apparatus according to claim 4, further comprising a switching signal generating circuit for performing the switching. 7. The power switching means comprises a current setting element for setting a predetermined current, and the low voltage of the power supply means is supplied with power to the current supply means via the current setting element of the power switching means. The recording / reproducing apparatus according to claim 5 or 6. 8. The recording / reproducing apparatus according to claim 7, wherein the recording medium has at least an optically reproducible optical area and a magnetic recording area. 9. The recording / reproducing apparatus according to claim 7, wherein the recording medium has a coercive force of 1600 Oersted or more, and the distance from the magnetic surface of the magnetic recording region to the magnetic head is 3 μm or more. .