JPH01285005A - Crosstalk reducing device magnetic recording and reproducing device - Google Patents

Abstract

PURPOSE:To reduce a crosstalk without executing a special shielding to a read/write core by opening the recording and reproducing coil of a read/write head in a non- selective condition at the time of the non-selection of the read/write head. CONSTITUTION:When the recording and reproducing coil of a read/write head 7 in the non-selective condition is opened by a switching means 8, the magnetic resistance of the read/write core, to which the recording and reproducing coil is wound, is lowered. Consequently, at the time of reading, a magnetic flux to be successively generated from the read/write gap of the read/write head 7 in the non-selective condition is prevented from leaking, the leaking magnetic flux is prevented from being chain-crossed to the recording and reproducing coil of the read/write head 7 in the middle of using, and a read crosstalk is reduced. At the time of writing, the magnetic flux generated from the recording and reproducing coil of the read/write head 7 in the middle of using is made to reduce the leakage of the read/write head 7 in the non-selective condition to the read/write gap, and a write crosstalk is reduced. Thus, without executing the special shielding to the read/write head 7, the read crosstalk and write crosstalk can be reduced.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to a crosstalk reduction device used in a magnetic recording/reproducing device using a flexible disk or the like as a recording medium.

BACKGROUND OF THE INVENTION FIG. 5 shows a read/write head portion of a magnetic recording/reproducing device. The read/write heads la and lb face each other with the flexible disk 2 in between.

The non-magnetic sliders 3a and 3b include a magnetic slider 4a as a conventional crosstalk reduction device.

4b is joined. One read/write spatula 1<l
When a current flows through the recording/reproducing coil 5a, magnetic flux is generated in the read/write core 6a, and this magnetic flux follows a path A indicated by an arrow.
The read/write core 6 of the other read/write head 1b
b, but here the magnetic slider 4b
becomes a shield.

Its leakage is reduced. Note that the recording/reproducing coils 5a, 5b of the read/write heads la, lb are always connected to a recording/reproducing signal processing section (not shown) regardless of whether they are in use or in a non-selected state.

Problems to be Solved by the Invention In such a conventional configuration, when the read/write head 1b is brought into a non-selected state using the read/write head 1a, the read/write core 6b of the non-selected read/write head 1b and the magnetic Since the flexible disk 2 is sandwiched between the body slider 4b and the flexible disk 2 to form a magnetic circuit, this greatly affects the magnetic properties of the read/write core 6a of the read/write head 1a in use, increasing the impedance of the recording/reproducing coil 5a. There is a problem in that the write and read characteristics of the read/write head 1a deteriorate.

SUMMARY OF THE INVENTION An object of the present invention is to provide a crosstalk reduction device that can reduce crosstalk without providing a special shield to the read/write core, and can further reduce the influence on the characteristics of a magnetic head more than ever before. .

Means for Solving the Problems The crosstalk reduction device of the present invention is a magnetic recording/reproducing device equipped with a plurality of read/write heads facing each other with a recording medium interposed therebetween. Flows a current according to the signal,
A switch means is interposed between the signal processing section that amplifies the signal of the read/write head during reproduction and opens the recording/reproducing coil of the read/write head in the unselected state when the read/write head is not selected. shall be.

According to this configuration, when the read/write coil of the non-selected read/write head is opened by the switch means, the magnetic resistance of the read/write core around which the read/write coil is wound decreases. Therefore, during reading, the magnetic flux continuously emitted from the read/write gap of the unselected read/write head is prevented from leaking, and the leaked magnetic flux is prevented from interlinking with the recording/reproducing coil of the read/write head in use. Reduce talk. During writing, the magnetic flux generated by the recording/reproducing coil of the read/write head in use reduces leakage into the read/write gap of the read/write head in a non-selected state, thereby reducing write crosstalk.

Embodiments Hereinafter, embodiments of the present invention will be explained based on FIGS. 1 to 4.

FIG. 1 shows a write/read circuit of a read/write head equipped with the crosstalk reduction device of the present invention.

It is connected to a signal processing unit IO consisting of 9c and 9d.

11 is a light switch, and 12 is a read head selection switch. During writing, the write switch 11 is turned on and the write signal A is applied to the transistors 9a and 9b. As a result, the current Iw determined by the current source 13 flows to the read/write head 7 via the diode port D2 of the switch means 8, and performs recording on the recording medium. When reading, read head selection switch 1
2 is turned on. As a result, a current source 14 is connected to the diode terminals lD, lD, , D4 of the switch means 8.
．． A current IB determined by 15 flows through these diodes D□
~D is turned on, the voltage of the read/write head 7 is applied to the transistors 9c and 9d, and the amplified read signal B
occurs.

When not selected, the write switch 11 and the read head selection switch 12 are open, so no current flows through the diode D□t02+039D4 constituting the switch means 8, and the read damping resistor 16 is connected to the recording/reproducing coil of the read/write head 7. When viewed from above, it is electrically open. During the read operation, the voltage generated across the recording/reproducing coil of the read/write head 7 on the non-selected side is
is a signal reproduced from the recording medium, and during a write operation, magnetic flux leaked from the recording/reproducing coil of the read/write head (not shown) on the selected side is induced by interlinking with the recording/reproducing coil of the read/write head 7. It is voltage. The voltage generated in the read/write head 7 on the non-selected side during this read operation and write operation cannot conduct the diodes Ds, D connected to the write damping resistor 17.
When not selected, the write damping resistor 17 is in an electrically open state when viewed from the recording/reproducing coil. In this manner, the recording/reproducing coil of the read/write head 7 can be electrically opened by the switch means 8 when not selected.

Note that the diodes D, , D, and the transistor 9a.

9b, current sources 13, 14.15, and transistors 9c, 9
The amplifier circuit consisting of d is integrated into a single integrated circuit. Transistors serving as switches 11.12 are also integrated into the integrated circuit.

Next, the operating principle of reducing crosstalk by opening the recording/reproducing coil of the read/write head on the non-selected side will be explained based on FIGS. 2 to 4.

FIG. 2 shows a model of the magnetic paths of the two read/write heads 7a and 7b facing each other with the recording medium 18 in between, and FIGS. 3 and 4 show the equivalent circuits of read crosstalk and write crosstalk in the same model, respectively. show. Here, the read/write head 7a is on the non-selection side, the read/write head 7b is on the selection side, 19a, 19b are recording/reproducing coils, 20
represents a damping resistor, and switch 21 represents switch means 8 that electrically opens the damping resistor 20 when not selected. Rg is the magnetic resistance of the read/write gap, and R and o are the magnetic resistances of the recording medium 18 across the read/write gap.
The magnetic resistance of the core portion in contact with , ROO represents the magnetic resistance other than the above-mentioned magnetic resistance □ of the core portion including the portion around which the recording/reproducing coil 19a is wound when the switch 21 is opened.

R6 is the magnetic resistance R1 between the two opposing read/write heads 7a and 7b, which is a composite magnetic resistance of the read gap of the read/write head 7b on the selection side and the core portion in contact with the recording medium 18, and Rol is the magnetic resistance of the read/write head 7b on the selection side. This is another magnetic resistance of the core portion including the portion around which the coil 19b is wound.

In the equivalent circuit of lead crosstalk shown in Figure 3,
If the magnetic flux from the recording medium 18 generated in the gap of the read/write head 7a on the non-selected side is 1, the magnetic flux that causes read crosstalk is i4, and the magnetic flux generated by the switch 2
Opening 1 is equivalent to eliminating the influence of the recording/reproducing coil 19a and lowering the magnetic resistance, and in FIG.
This is equivalent to closing the switch 21 and placing the magnetic resistance R8o11 of the read/write head 7a in parallel with the magnetic resistance R80. In FIG. 3, the magnetic flux that contributes to read crosstalk is i4, and the ratio of this to one magnetic flux that contributes to reproduction is read crosstalk.

Next, in the equivalent circuit of light crosstalk in Figure 4,
E is the magnetomotive force generated in the read/write coil of the read/write head 7b on the selection side. The magnetic flux contributing to write crosstalk is i□, and the magnetic flux contributing to writing is i□.

Here, since R+=2R fog 0+R-, it has the effect of reducing light crosstalk.

Effects of the Invention As described above, the present invention provides a read/write head;
A current is passed through the read/write head in accordance with the write signal during recording, and between the signal processing section that amplifies the signal from the read/write head during playback.

Since a switch means is provided to open the recording/reproducing coil of the unselected read/write head when the read/write head is not selected, the magnetic resistance of the read/write core around which the recording/reproducing coil is wound is reduced. This has the effect that both read crosstalk and write crosstalk can be reduced without providing a special shield to the read/write head. Further, since the coil of the non-selected head is simply electrically opened, it has the advantage of not affecting the characteristics of the selected read/write head.

[Brief explanation of the drawing]

Fig. 1 is a signal processing circuit diagram of a read/write head that employs the crosstalk reduction device of the present invention, and Fig. 2 shows a signal processing circuit diagram of a read/write head that uses the crosstalk reduction device of the present invention in two read/write heads facing each other with a recording medium in between. Magnetic path model diagram for case 3
The figure is an equivalent circuit diagram of read crosstalk in the same magnetic path model, Figure 4 is an equivalent circuit diagram of write crosstalk in the same magnetic path model, and Figure 5 is a longitudinal cross-section of a read/write head using a conventional crosstalk reduction device. It is a front view. 7... Read/write head, 8... Switch means,
10... Signal processing unit. Agent Yoshihiro Morimoto Figure 1 Light SW Figure 3 Figure d

Claims (1)

[Claims] 1. In a magnetic recording/reproducing device equipped with a plurality of read/write heads facing each other with a recording medium in between, a current is passed through the read/write head in accordance with a write signal during recording, and a current is applied to the read/write head during playback. A crosstalk reduction device interposed between a signal processing section that amplifies a signal and a switch means for opening a recording/reproducing coil of a read/write head in an unselected state when the read/write head is not selected.