JPS623481B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a perpendicular magnetization recording/reproducing device particularly suitable for high-density recording.

In recent years, perpendicular magnetization recording has been developed as being suitable for high-density recording. In particular, it is known that good perpendicular high-density recording can be achieved when a permalloy film of high magnetic permeability is brought into contact with the film surface of a magnetic recording medium, and a large auxiliary head is used as the main head for excitation recording from the rear surface. However, it is impractical to use the same device to obtain a signal from an auxiliary head to reproduce this recording because the output is weak. Therefore, the current situation is to use a conventional ring head for regeneration. This complicates the configuration.

This invention combines the high magnetic permeability material of the main head with magnetoelectric conversion elements such as Hall elements, magnetoresistive elements, magneto diodes, magnetic transistors, etc., and generates an effective output by the magnetic field picked up by the main head even during playback. The gist is that.

FIG. 1 shows an embodiment of the invention.

For example, 1 is a magnetic tape base, and 2 is a magnetic film, preferably one for perpendicular magnetization. Reference numeral 3 denotes a main head for recording, which is a plate or film made of a high magnetic conductivity material such as permalloy fixed with plastic or the like, and is in contact with 2 for scanning. Reference numeral 4 denotes an auxiliary head, through which a recording current is passed through a winding 60 from leads 5 and 6. It is known that such a device can perform high-density perpendicular recording. However, when the same tape is used for playback, leads 5 and 6
The output is extremely weak and difficult to put into practical use. It is almost the same even if the coil is wound around 3. 7 is 3 according to the present invention
8 is a highly magnetic material similar to 3 used as required. These main head assemblies are indicated at 22.

Figures 2a, b, c and d show 22 detailed examples.
In a, the magnetically sensitive body 7 is a Hall element that utilizes the Hall effect of Si, Ge, or other semiconductors. Therefore, when a current is passed through 7 using a bias power supply 11 and an appropriate resistor 12, the magnetomotive force induced in 3 causes a current in leads 16 and 17 in a direction perpendicular to the current in 7 to be proportional to the magnetic field and corresponding to the direction of the magnetic field. A voltage is generated. 3 shows an example made of plastic, ceramic, etc., with a film 10 of permalloy or the like sandwiched therebetween or vapor-deposited on the surface. A material similar to 3 may be used as 13 and attached to the opposite side of 7. Hall element materials are Si, InSb,
InAs, GaAs, Bi, and other materials are used, and they are made as thin films by vapor deposition. The orientation of No. 10 is such that the longitudinal direction and the scanning direction are substantially perpendicular to each other.

In FIG. 2b, a magnetoresistive element 7, ie, InSb, NiSb, Sb, InAs, etc., whose resistance changes with a magnetic field is used. At this time, bias source 11, resistor 14,
15 etc., leads 16, 17 and 7 depending on the magnetic field.
The resistance changes and gives a playback output. However, the direction of the magnetic field is irrelevant and generally has a square characteristic.

Figures 2c and d are examples of main head configurations; c is the front;
d shows a side view. On the substrate 19, permalloy 10, Si, Ge 7, and permalloy 13 are deposited as thin films of about μm by vapor deposition or other methods.
Such configurations may be multiplexed. No. 19 can also be made into an IC using Si.

FIG. 3 shows a modification of the head assembly shown in FIG. 1, in which the main head assembly 22 is connected to the auxiliary head 4 by a yoke or holder 20 to maintain a predetermined gap and position.
Incidentally, depending on the traveling speed of the recording medium, 3 and 4 may be slightly shifted from the symmetrical position and magnetized completely perpendicularly. Yoke 20 may also be made of a highly magnetically conductive material. Also, a wire may be wound around this part.

FIG. 4 is a modification of the head system of FIG. 1, in which the main head 3 also has a winding 61 on permalloy. Although the reproduction output of 61 coils is generally higher than that of 4 coils, it is still insufficient, and in some cases, the output of the magnetically sensitive semiconductor element 7 may be used in combination.

FIG. 5 shows main head modifications a, b, and c of the invention.

In a, a magnetically sensitive semiconductor film made of permalloy or the like is made by sequential vapor deposition on a substrate 19 of Si or the like, and the aggregate 2
2'. As a result, highly sensitive reproduction output is obtained. In b, an assembly 22'' is shown which has a multilayer structure and has increased sensitivity.Semiconductors 7 and 7'' may be connected.
c is 22'', which is obtained by converting 3 and 7. It is better to connect the films 3 and 3' of permalloy at the bottom to form a yoke shape as shown in the figure, and apply a strong magnetic field to 7. However, when recording The reproduction density is reduced by a gap of 3.3'.In this way, an arbitrary number of elements are stacked one on top of the other, and the whole is solidified with resin or the like and wrapped.

These semiconductors include Hall elements, magnetoresistive elements,
Magnetic diodes, magnetic transistors, or anything else will do.

Figures 6 a, b, c, d, and e are examples of elements for Figures 1 and 5. A is a cross-shaped Hall element with increased sensitivity 70, and b is a Hall element with the voltage terminals connected. A magnetoresistive element 71, c is a magnetoresistive element 72 whose sensitivity is increased by dividing multiple elements in series, and d is a magnetoresistive element 73 whose sensitivity is increased by zigzag bending, all of which can be integrated into an IC. Furthermore, instead of using Si as a substrate, a magnetic semiconductor thin film can be attached to a high magnetic permeability material such as permalloy or sendust, thereby achieving high sensitivity. e is an example in which a high magnetic conductivity material is embedded in the gap d. The layers may be stacked in a shifted manner as shown in e. Since the total thickness of the operating part of the head assembly is about several microwatts, the whole can be wrapped in resin, ceramic, glass, etc., and can be shaped into a normal head shape so that it can easily come into contact with tape or the like.

Hall materials having a shape such as that shown in FIG. 6a may also be successively laminated with a cross-shaped material rotated by 45 degrees with a high magnetic permeability material inserted therebetween.

The recording/reproducing head assembly according to the present invention can be applied to all magnetic recording devices, especially for high-density analog and digital recording. Magnetoresistive elements are particularly suitable for digital applications.

Figures 7a and 7b show examples of its application; if the cylinder 25 is rotated by the drive unit 40 and a magnetic sheet is placed inside with the film surface facing inside, the sheet will be stably held within the cylinder by centrifugal force. This is as described in patent application No. 53-37515 filed by the inventor. Heads 4 and 22 and yoke 20
In this example, the guide groove 26 on the outer periphery of the cylinder 25,
It is sent by the guide pin 30 attached to 4. 41 is a fixed arm, and 76 is a rail on which 20 slides.
Also, 35 is a signal source, 36 is a recording amplifier, and lead 3
Reference numerals 1 and 32 are magnetic element output leads of the main head assembly, and a reproduction output 34 is obtained from the reproduction amplifier 83. Of course, the signal and head are switched during recording and playback.

FIG. 7b shows a partially modified example of a, in which a guide groove 26 is cut inside the cylinder, and the main head or a pin attached thereto pushes around the sheet to move the head assembly.

FIG. 8 is a modification of FIG. 7, in which the head system is moved from a motor rotating shaft 29 through gears 42, 43, 44 and a screw 45. Although it is suitable for high-density recording as it allows for arbitrary slight movements, it is better to eliminate mechanical backlash and add a tracking servo.

In FIG. 9, a partially conical tube or disk 50 is used instead of the cylinder shown in FIG. 7, and the magnetic sheet inserted therein may be endless. Although the head is fed by the feed groove 26 and the feed pin 30 as in FIG. 7, it may also be as shown in FIG. Of course, the cone may also be a disk.

FIG. 10 shows rotating only the conical magnetic sheet,
It scans in the same way, and although it has a simple structure, it can rotate and scan stably. This is the patent application filed by the inventor in 1973.
As described in No. 40992.

The edge 56 may be made thicker or reinforced with another material.

In the present invention, the magnetoelectric transducer of the main head component that utilizes the Hall effect has good linearity and is suitable for analog applications. Magnetoresistive elements and magnetic diodes have high sensitivity but are nonlinear, so they are mainly suitable for digital applications. However, depending on the structure, such as a well-known magnetoresistive element, linear characteristics can be provided. Furthermore, by adding an appropriate bias magnetic field, it can be made almost linear.

High magnetic conductivity materials include permalloy, super permalloy, alphenol ferrite, sendust, and other magnetic materials that are difficult to form and wear, but since sendust is difficult to vapor-deposit, it is also possible to use a Hall material, etc., vapor-deposited on top of sendust. . The auxiliary head does not require contact, so it is semi-permanent.

The magnetic recording/reproducing head according to the present invention is extremely thin and compact, making it suitable as a combination head. For example, it is used for azimuth recording and reproduction, and throws, steals, etc. are performed smoothly.

FIG. 11 shows an example of azimuth recording. A magnetic tape 100 is obliquely recorded 10 by a rotating head.
1, 102, and 103 are lined up and alternately have different azimuths, allowing for close recording. This is based on the inventor's proposal, Utility Model Publication No. 38-23924. Further, the horizontal lines of adjacent records are arranged to face each other. This is based on the inventor's proposal, Japanese Patent Publication No. 36-22002. Because of the azimuth head, it was considered difficult to play back slows, steals, etc. from such records.

Figures 12a, b, c, d and e show examples of video recording devices of the present invention. The rotating head drum 104 is b
As shown in the side view at front c, heads 110 and 111, which are approximately symmetrical, are each made up of a pair of azimuth heads, which are the aforementioned main heads, and are several micrometers thick and several tens of micrometers long. And then,
They can be placed in almost the same position. 105 of a is a head motor, 106 is a transmission device via 107,
An external head ring 115 is rotated, and two auxiliary heads for recording are attached to the external head ring 115. The auxiliary head is large and covers two heads with different azimuths,
Two sets of recording traces such as recording traces 101 and 102 in FIG. 11 are recorded for one field with the same signal using one set of azimuth heads, and then recording traces 103 and 104 are recorded using another head.

The tape may be wound around the head cylinder once in a one-head configuration.

There is no problem with normal playback, but playback traces cross obliquely with recorded traces when playing slow, still, etc. The reproducing head of the present invention as shown in FIG. 12 can always perform good reproduction by using the element heads of azimuth heads 110 and 111 together or by switching them.

Incidentally, the configuration as shown in FIG. 12a is detailed in Japanese Patent Application No. 1983, pending application by the inventor. The main head and auxiliary head may be replaced, but it is easier to improve accuracy if the main head scans from the inside.

In addition, using the well-known Skipscan, the 11th
The recording traces 101 and 102 shown in the figure may be recorded in recording properties 103 and 104 in one field, and the same pair of recording traces may be scanned twice during reproduction. Alternatively, a separate recording/reproducing head may be provided.

Figures 12d and 12e show a top view d and a side view e of such a head drum. 120 and 121 are a pair of recording heads having different azimuths; 12
2,123 is a combination azimuth head like 110,111 for regeneration.

The head drum 104 may have a known structure in which it rotates between two fixed cylinders.

The recording and reproducing apparatus according to the present invention is characterized in that a head configuration suitable for perpendicular magnetization recording and reproducing is generally provided by combining a high magnetic permeability sheet and a magnetoelectric conversion sheet, and further various configurations are possible. This type of head can also be used for playback of conventional lateral recording, providing compact broadband characteristics.

During recording, the main head of the present invention can monitor the voltage generated by the magnetoelectric transducer, or the output can be NFBed to an amplifier to improve the characteristics.

FIG. 13 shows this circuit, in which the output of the magnetoelectric transducer of the head 22 is negatively fed back to the recording amplifier 36.

FIG. 14 shows another embodiment of the invention in which the main head assembly of the invention is offset as shown and tilted slightly as required with respect to the auxiliary head 4. As the medium 1 advances, the recording magnetization direction tilts toward the film plane as shown in B and B'. Therefore, it is possible to identify adjacent recording traces by utilizing this inclination, as described in Japanese Patent Application No. 1983, filed by the inventor. However, the effect is small if the main head output is not used effectively during reproduction, so if 22 and 22' are used in combination with a magnetoelectric transducer and a high magnetic permeability film as described above, it is possible to achieve close recording as in the conventional azimuth recording method. Adjacent records can be discriminated.

FIG. 15 is an example of a rotating head using head wires with different magnetization directions as shown in FIG. 14 for use in VTRs and the like.

Of course, it is possible to further increase the effect by using it in conjunction with azimuth recording as shown in FIGS. 11 and 12, and for this purpose, the heads 22, 22' may be further tilted in the direction of the azimuth angle.

This pattern is shown by dotted lines 130, 130'.

The present invention is not limited to the above-mentioned specific example, and various modifications and other combinations of the embodiment parts are possible.

[Brief explanation of the drawing]

FIG. 1 shows an embodiment of a recording/reproducing apparatus according to the present invention. 1... Recording medium base, 2... Magnetic film, 3, 8
... High magnetic conductivity film, 7 ... Magnetoelectric conversion semiconductor, 4 ...
Auxiliary head, 60...coil, 5, 6...input lead. Figures 2a, b, c and d show examples of main head assemblies. 10... High magnetic conductivity film, 11... Power supply, 12,1
4, 15...Resistance, 22...Main head assembly, 1
6, 17...Reproduction output lead, 19...Board. FIG. 3 shows an embodiment of the invention. 20...York. FIG. 4 shows a modification of FIG. 61...Main head winding. Figures 5a, b and c show main head assemblies according to the invention. FIGS. 6a, b, c, d, e, and e' show four examples of magnetoelectric conversion elements. 70... Cross-shaped element, 71... Magnetoresistive element using Hall element, 72, 74... High sensitivity magnetoresistive element. Figures 7a and 7b show an embodiment of the invention. 25... Cylinder, 26... Guide groove, 28... Magnetic sheet, 29... Rotating shaft, 30... Guide pin, 35... Signal source, 36... Recording amplifier, 33
... Reproduction amplifier, 40 ... Drive means, 41 ... Arm, 82 ... Unit. FIG. 8 shows a modification of FIG. 7. 42, 43, 44...gear, 45...screw, 46...rail. FIG. 9 shows a modification of FIG. 52... Conical cylinder or disk, 77... Magnetic sheet. FIG. 10 shows an embodiment of the invention. 52...Conical or disc magnetic sheet, 55...Reduction portion, 56...Edge. FIG. 11 shows an example of azimuth recording. 100...magnetic tape, 101, 102, 10
3,104...Successive records. 12a, b, c, d, and e show a VTR of the present invention which performs the recording shown in FIG. 11. 104... Rotating head drum, 105... Head motor, 106... Transmission section, 107... Rod, 1
15...External head ring. Figures 12b and 12c show front and side views of the head drum, respectively. 110, 111...Combination azimuth head. Figures 12c and d show modifications of b and c. 120, 121...1 pair of azimuth heads, 1
22,123...a pair of combined azimuth heads. FIG. 13 shows an embodiment of the invention. FIG. 14 shows an example of a head assembly with different magnetization directions. 15th
The figure shows a rotating head drum 1 as shown in Figure 14.
The one applied to 04 is shown.

Claims (1)

[Claims] 1 A high magnetic permeability thin piece, a magnetically sensitive semiconductor element engaged with the high magnetic permeability thin piece, a recording means for generating magnetization in a magnetic recording medium, and a reproduction output from the magnetically sensitive semiconductor element in response to the recording means. and the means to obtain
A recording/reproducing apparatus comprising means for negatively feeding back an output obtained from the magnetically sensitive semiconductor element to a recording circuit during recording.