JPS6353603B2 - - Google Patents

Description

[Detailed description of the invention]

It is well known that various recording and reproducing methods have been proposed in the past in order to realize the demand for high-density recording of information signals on recording media. In recording/reproducing devices, in order to achieve high-density recording of information signals, for example, magnetic heads for recording/reproducing must have a magnetic gap whose longitudinal direction is smaller than the direction perpendicular to the direction in which the recording trace extends. By using a magnetic recording medium that is tilted by an angle and allowing adjacent recording traces on a magnetic recording medium to be recorded and reproduced by magnetic heads having different azimuth angles, information on adjacent recording traces can be To prevent reproduction due to so-called azimuth loss, to eliminate the need for unrecorded areas (guard bands) between adjacent recording tracks, and to achieve high-density recording on magnetic recording media, and various other means. have been proposed or implemented. By the way, in conventional magnetic recording and reproducing devices, recording of information signals on a magnetic recording medium and reproduction of information signals from the magnetic recording medium are performed using a magnetic head in which a minute magnetic gap is formed in a part of a ring-shaped magnetic core. Therefore, the residual magnetization generated in the magnetic layer of the magnetic recording medium in response to the information signal is in a form that extends in the direction of relative movement between the magnetic recording medium and the magnetic head. It has become a thing. Therefore, a demagnetizing effect between the residual magnetizations in the magnetic layer of the magnetic recording medium acts to cause a decrease in the residual magnetization, and as a result, the reproduced signal becomes small. The decrease in residual magnetization in the magnetic layer due to the demagnetization effect described above increases as the recording wavelength on the magnetic recording medium becomes shorter, and when the recording wavelength on the magnetic recording medium becomes extremely short. Since a phase shift also occurs in the reproduced signal, it is necessary to use a method in which the residual magnetization in the magnetic layer extends in the direction of relative movement between the magnetic recording medium and the magnetic head, as in the conventional magnetic recording and reproducing method. If this were the case, it would be impossible in principle to achieve even higher density recording. In recent years, a magnetic recording and reproducing method using the so-called perpendicular magnetization recording method has been attracting attention as a magnetic recording and reproducing method that does not have the limitations on high-density recording that occur in principle in the conventional magnetic recording and reproducing method as described above. Ta. This magnetic recording/reproduction method using perpendicular magnetization recording is, for example, a magnetic recording medium equipped with a perpendicular magnetization film made by vertically growing cobalt-chromium alloy crystal fine particles with a close-packed hexagonal structure with an average grain size of 0.1 micron or less. A thin main magnetic pole made of a soft magnetic material is disposed on the perpendicularly magnetized film (magnetic layer) side so that one end face thereof faces the magnetic layer surface, and the magnetic layer in the magnetic recording medium is An auxiliary magnetic pole formed by winding a magnetic core having a larger cross-sectional area than the main magnetic pole is placed on the opposite side to the main magnetic pole so that the end face of the magnetic core faces the end face of the main magnetic pole. The recording of information signals onto a traveling magnetic recording medium and the reproduction of information signals from the magnetic recording medium are performed by a magnetic head set which is disposed in It is meant to be done. In the magnetic recording and reproducing system using this perpendicular magnetization recording method, residual magnetization in the magnetic layer occurs in a direction perpendicular to the running direction of the magnetic recording medium, that is, in the thickness direction of the magnetic layer, so a demagnetizing effect acts on the residual magnetization. Moreover, since there is a possibility that high-density recording can be realized down to the smallest magnetic domain unit of the magnetic layer, research and development in various fields is progressing as a promising magnetic recording and reproducing method for the future. Now, in order for an information signal to be recorded and reproduced by a recording medium, the signal component of the highest frequency value in the information signal to be recorded and reproduced must have a length of 1/2 of the recording wavelength on the recording medium corresponding to the signal component of the highest frequency value in the information signal to be recorded and reproduced. Since it is necessary that the relative speed between the recording/reproducing element and the recording medium is determined so that the recording/reproducing element has a length that can be discriminated by the recording/reproducing element. If the information signal to be recorded has a wide occupied frequency band, such as a television signal, the recording/reproducing element and the recording medium must have a large relative speed when recording and reproducing the information signal. Must be. Therefore, in a magnetic recording/reproducing device that uses magnetic tape as a recording medium, the magnetic head, which is the recording/reproducing element thereof, is in a fixed state, and when recording and reproducing information signals, the magnetic head and the magnetic tape are connected. If you try to record and reproduce television signals using a magnetic recording device in which the relative speed required between the The running speed of the tape becomes very high, and the amount of magnetic tape required increases. Therefore, even when recording and reproducing information signals requires a high relative speed between the magnetic head and the magnetic tape, it is possible to record and reproduce for a long time with a small amount of magnetic tape. As a means of achieving this, information signals have been recorded and reproduced using a magnetic head that moves at high speed in the widthwise direction or diagonally of a magnetic tape that runs at a slow running speed. That is, a rotating magnetic head assembly is constructed by attaching one or more magnetic heads to a disk or drum in such a manner that the magnetic gap protrudes from the outer peripheral surface of the disk or drum. Conventionally, it has been widely practiced to record and reproduce information signals by running a magnetic tape running at a slow speed along the outer peripheral surface of a rotating magnetic head assembly rotating at a high speed. It is well known that this is coming. However, the rotating magnetic head assembly having the configuration described above cannot be applied to the magnetic recording/reproducing apparatus using the perpendicular magnetization recording method as described above. The magnetic head set for recording and reproducing is
A main magnetic pole arranged on one side of the magnetic tape,
This is obvious from the point that it is necessary to consist of a pair of auxiliary magnetic poles placed on the other side of the magnetic tape and facing the above-mentioned main magnetic pole. . The present invention uses a rotating magnetic head assembly having a special configuration in a magnetic recording and reproducing apparatus that magnetically records and reproduces information signals according to a magnetic recording and reproducing method using perpendicular magnetic recording.
It is possible to record and play for a long time with a small amount of magnetic tape, and it also enables the recording and playback operation to be performed with the magnetic head set correctly following the recording trace during recording and playback, thereby achieving even higher density. The purpose of this invention is to provide a magnetic recording/reproducing apparatus that can achieve recording, and the specific contents of the magnetic recording/reproducing apparatus of the present invention will be described in detail below with reference to the accompanying drawings. FIG. 1 is a perspective view showing the principle of construction of a rotating magnetic head assembly used in the magnetic recording/reproducing apparatus of the present invention. In FIG. The magnetic tapes 3 and 4 are disks that are fixed to the rotating shaft 2 with a gap (for example, 100 μm) that allows the magnetic tape 1 to run, and the disk 4 has a specific radius in its plane. Main magnetic poles are arranged as required on the circumference shown, and auxiliary magnetic poles are provided on the disk 3 at positions facing the main magnetic poles on the disk 4 described above. Therefore, in the gap between the two disks 3 and 4, the magnetic layer side of the magnetic tape 1 faces the disk 4,
The magnetic tape 1 is run in the direction of the arrow with the base side of the magnetic tape 1 facing the disk 3, and the disks 3 and 4 are rotated by the rotating shaft 2 in the direction of the arrow B in the figure.
When the tape is rotated at high speed in the direction, information signals are recorded on the magnetic layer (perpendicularly magnetized film) of the magnetic tape 1 in a predetermined shape of recording trace by successive sets of magnetic heads provided on the disks 4 and 3. Or, it is possible to reproduce information signals recorded on magnetic tape. FIG. 2 is a front view of the magnetic tape 1 and disk 4 seen from the gap between the two disks 3 and 4 that constitute the rotating magnetic head assembly shown in FIG. In Figure 2, 11a, 12a,
11b, 12b, etc. indicate main magnetic poles arranged in a required manner on a specific circumference within the plane of the disk 4, and among the main magnetic poles, those with the subscript a are information The main magnetic pole is used as a component of a magnetic head assembly for signal recording and reproduction, and those with the subscript b among the main magnetic poles are used as constituent elements of a magnetic head assembly for reproduction. This is the main magnetic pole. In the example shown in the second figure, the disk 4 by the rotating shaft 2
rotation in the direction of arrow B and the rotation of magnetic tape 1 in the direction of arrow A
By traveling in the direction, the main magnetic poles belonging to the magnetic head sets for recording and reproducing information signals provided on the disk 4 sequentially draw the rotation locus on the magnetic tape 1, and corresponding recording traces are created in the adjacent direction. Although the main magnetic pole having a reverse azimuth is shown as being composed of a main magnetic pole having a reverse azimuth, this is the magnetic head assembly for recording and reproducing information signals of the magnetic head assembly group for recording and reproducing information signals provided on the disk 4. The main magnetic poles belonging to the disk 4 are arranged in such a manner that the longitudinal direction in the cross section of the thin film main magnetic pole is inclined in opposite directions alternately by a predetermined angle with respect to the radial direction of the disk 4. This is because the main magnetic pole 11a and the main magnetic pole 12a in FIG.
You can understand it immediately by looking at the state of the slope. In addition, the main magnetic poles 11b, 12b, etc. in the magnetic head group for reproduction that belong to the magnetic head group for reproduction belong to the magnetic head group for recording and reproducing information signals immediately preceding the magnetic head group for reproduction to which the main magnetic poles belong. It is assumed that the inclination mode is the same as that of the main magnetic pole, and this point can be seen by looking at the inclination mode of the main magnetic pole indicated by 11a and 11b, and 12a and 12b, respectively, in Fig. 2. You can understand it immediately. Figure 3 shows the main magnetic pole mp provided on the disk 4.
(11a, 11b, 12a, . . . in FIG. 2) and an auxiliary magnetic pole ap provided on the disk 3 form a pair. This shows the relationship between one magnetic head set and the magnetic tape 1. In FIG. 3, the main magnetic pole mp is formed by depositing a thin film 6 of a material with high magnetic permeability on a support 5 made of a non-magnetic material by vapor deposition or sputtering. The thin film 6 described above has a thickness of, for example, 0.1 to 3 μm. In addition, the auxiliary magnetic pole ap includes a winding 7b on a magnetic core 7a made of a soft magnetic material having a cross-sectional area larger than that of the thin film 6 of a material having high magnetic permeability (thin film made of a soft magnetic material) of the main magnetic pole MP. It is something that can be done. The main magnetic pole mp provided on the disk 4 has its end surface in contact with the surface of the perpendicular magnetization film 1c on the magnetic tape 1, and the auxiliary magnetic pole ap faces the main magnetic pole ap via the magnetic tape 1. There is. In addition, in FIG. 3, the magnetic tape 1 is shown as being composed of a base 1a made of a non-magnetic material, a horizontally magnetized film 1b, and a vertically magnetized film 1c. The magnetized film 1c constitutes a magnetic layer. A recording signal is supplied to the winding 7b of the auxiliary magnetic pole ap during recording, and a reproduction signal appears thereon during reproduction. As mentioned above, the rotating magnetic head assembly used in the magnetic recording/reproducing apparatus of the present invention includes a disk 4 provided with a main magnetic pole and a disk provided with an auxiliary magnetic pole that pairs with the main magnetic pole. 3 is fixed to the rotating shaft 2 with a gap of, for example, about 100 μm between both disk surfaces, and the main magnetic pole and auxiliary magnetic pole that constitute each magnetic head set face each other. By running the magnetic tape 1 through the gap between the disks 3 and 4 and rotating the rotating magnetic head assembly at high speed, the magnetic head sets for recording and reproducing information signals sequentially record information on the magnetic tape 1 one after another. Since it is made so that marks are formed, the size of the disks 3 and 4 (or the diameter of the circle where the auxiliary magnetic pole and the main magnetic pole are placed on the surface of the disks 3 and 4)
There is a specific relationship between the width of the magnetic tape (or the recording width of the magnetic tape), the number of main magnetic poles and auxiliary magnetic poles, and the main magnetic poles that should be provided on opposite sides of the disks 4 and 3. The end faces of the magnetic poles and auxiliary magnetic poles are required to be flush with the surface of the disk 4 and the surface of the disk 3. Now, the rotation trajectory drawn by the main pole of the magnetic head assembly provided on the rotating disk 4 on the magnetic tape 1 running at a constant speed becomes a turquoid curve as shown in FIG. Now, as shown in Fig. 4, the rotation angle of the disk is θ (radian), the running distance of the magnetic tape per one rotation of the disk is a, and the running direction of the magnetic tape is the -X direction. Assuming that the rotation angle θ is 0 on the +y axis and positive in the counterclockwise direction, the turquoid curve shown in FIG. 4 is expressed by the following equation (1). X=aθ−bcosθ y=bcosθ ……(1) {However, in equation (1), b is the rotation drawn by the outermost end of the main magnetic pole located on the circumference of a specific radius on the disk surface. The running speed a of the magnetic tape is expressed by the following equation (2), where P is the recording track pitch and N is the number of circumferential divisions by the main pole. a=NP/2π (2) From the above equations (1) and (2), the substantial track pitch d is expressed by the following equation (3). In FIG. 4, W is the width of the recording area on the magnetic tape, B is the rotation direction of the main pole, θ ₁ ,
θ ₂ is the rotation angle from the +y axis when the main pole is located at both ends of the recording area of the magnetic tape, P is the track pitch, and α is the angle between the outer end of the main pole and the −x axis. Then, based on the above formula, the rotation speed No. of the disk,
The diameter 2b of the rotation locus circle at the outer end of the main pole, the number N of circumference divisions by the main pole, the width W of the recording area, the track pitch P, the effective width do of the track, etc. are determined. FIG. 5 shows a situation in which recording traces T ₁ , T ₂ , T _{3 .} . . are recorded on a magnetic tape whose recording area has a width W by main magnetic poles 11a, 12a, 13a . . . whose effective width is do. FIG. 5 shows a state in which the recording trace _T2 has been recorded up to the middle of the recording trace by the magnetic head set to which the main magnetic pole 12a belongs. Incidentally, T ₃ indicates, for reference, the recording trace to be recorded by the magnetic head set to which the main magnetic pole 13a belongs. Since the actual track pitch d reaches its maximum when the rotation angle θ of the main magnetic pole is θ≈π/2, the distance between each recording track is determined by the difference between d shown in equation (3) and the effective width do of the main magnetic pole. A corresponding unrecorded portion occurs. N on the circumference of the disk surface of disk 4 with a predetermined radius
The main magnetic poles of the information signal recording/reproducing magnetic head set are provided at the dividing positions, and the circles of a predetermined radius on the disk surface of the disk 3 are arranged to form pairs with each of the above-mentioned main magnetic poles and to face each of the main magnetic poles separately. The auxiliary magnetic poles provided at N-divided positions on the circumference refer to each pair of main magnetic poles and auxiliary magnetic poles provided on each disk 4, 3 that face each other across the gap between the disks 4, 3. The disks 4 and 3 constitute a rotating magnetic head assembly having N magnetic head sets for recording and reproducing information signals. A set of N magnetic heads for recording and reproducing information signals, which is composed of pairs of N main magnetic poles and N auxiliary magnetic poles arranged at equal angles on the disks 4 and 3, is used to record and reproduce a certain piece of information. When the magnetic head set for recording and reproducing information reaches the recording area on the magnetic tape, the set of magnetic heads for recording and reproducing information signals that precedes the set of magnetic heads for recording and reproducing information signals deviates from the recording area on the magnetic tape. In this manner, successive records T ₁ , T ₂ . A set of magnetic heads can follow successive records on the magnetic tape. If the total number N of the N magnetic head sets for recording and reproducing information signals, which are provided by dividing the circumference of the disk with a predetermined radius into N, is an odd number, then The main magnetic poles belonging to each magnetic head group for recording and reproducing information signals in the magnetic head group for recording and reproducing information signals have the same inclination angle (inclination angle and However, the total number N of magnetic head sets for recording and reproducing information signals constituting the group of magnetic head sets for recording and reproducing information signals described above.
is an even number, the main magnetic poles belonging to the odd-numbered information signal recording/reproducing magnetic head groups and the main magnetic poles belonging to the even-numbered information signal recording/reproducing magnetic head groups are arranged so that the longitudinal direction of the cross section of the main magnetic poles is The disks 4 are tilted in opposite directions by a predetermined angle with respect to the radial direction of the disk 4, and the sequential information signals recorded and formed on the magnetic tape by the magnetic head sets for sequential information signal recording and reproduction are recorded on the magnetic tape. It is also possible that the recording traces T ₁ , T _{2 .} . . are sequentially and alternately in reverse azimuth states as shown in the fifth figure. When the main magnetic poles of the sequential information signal recording/reproducing magnetic head groups in the information signal recording/reproducing magnetic head group are sequentially and alternately showing reverse azimuth as described above, the information signal recording A reproducing magnetic head set for reproducing a tracking information signal is provided at a predetermined position between adjacent magnetic head sets for recording and reproducing information signals in a group of reproducing magnetic head sets, and tracking control of the reproduced signal from the set is provided. It can also be used for tracking control of magnetic recording and reproducing devices. This tracking control will be described later. The main magnetic pole in the magnetic head set for reproducing described above has the same inclination as the main pole belonging to the immediately preceding set of magnetic heads for recording and reproducing information signals. As mentioned above, the disk 4 on which N or 2N main magnetic poles are arranged, and the disk 3 on which the auxiliary magnetic poles making a pair with the main magnetic poles are arranged, are integrally connected by the rotating shaft 2. A rotating magnetic head assembly is constructed, and an example structure of the rotating magnetic head assembly will be described below with reference to FIG. In FIG. 6, disk 4 and disk 3 are connected to bearing 7.
Magnetic tape 1 is mounted on rotating shaft 2 supported by
They are attached via a spacer so that they face each other with a gap that allows them to run. The disk 4 is provided with main magnetic poles in a predetermined arrangement manner, and the disk 3 is provided with auxiliary magnetic poles in a predetermined arrangement manner. A recording signal current is supplied to the winding in the auxiliary magnetic pole (indicated by 7b in FIG. 3) during recording;
Furthermore, during reproduction, a reproduction signal is induced. 71 is a changeover switch for switching and supplying a recording signal current to the auxiliary magnetic poles belonging to the magnetic head for sequentially recording and reproducing information signals during recording, a changeover switch for switching and extracting the signals reproduced by the auxiliary magnetic poles during reproduction, and others. 70a is a component on the rotating side of the rotary transformer, 70b is a component on the fixed side of the rotary transformer, and 72 is a component on the rotating side of the rotary transformer such as the substrate 71, the disk 3, and the rotary transformer. It is a cylinder in which the side component 70a and the like are assembled integrally. In addition, 77a and 77b are slip rings, 78
a, 78b are brushes, and 76 is a coupling coupling the rotating shaft 2 with the rotating shaft of the motor 75. The magnetic tape 1 is supplied, for example, from a supply reel 81 in a cassette 80 to a roller 83 → a capstan 85 and a pinch roller 87 → a gap between disks 4 and 3 → roller 8
4 to the take-up reel 82. In FIG. 6, 86 is a capstan motor, 88a, 88b are erase heads, 90a, 90
b is an audio erasing head, and 89a and 89b are audio recording/reproducing heads. Before the cassette 80 is installed, the pinch roller 87 is separated from the capstan 85, and with the cassette 80 installed, the magnetic tape 1 is set along a predetermined magnetic tape running path, and during recording or playback. The pinch roller 87 is pressed against the capstan 85, and the magnetic tape 1 is run at a predetermined running speed. With respect to the disks 3 and 4, the running path of the magnetic tape 1 is configured, for example, as shown in FIGS. 1 and 2, and the magnetic layer of the magnetic tape 1 is in sliding contact with the end surface of the main pole of the disk 4. In this state, it runs through the gap between the disks 3 and 4. As mentioned above, the magnetic head assembly used in the magnetic recording and reproducing system using the perpendicular magnetization recording method consists of a main magnetic pole in the form of a thin film and a thin film-like main pole provided in a direction perpendicular to the tape surface so as to sandwich the magnetic tape from both sides of the magnetic tape. , and a pair of auxiliary magnetic poles. In the magnetic recording/reproducing apparatus of the present invention, a plurality of magnetic head sets are composed of a pair of main magnetic poles and auxiliary magnetic poles arranged on the disks 4 and 3. Next, the main magnetic pole and the auxiliary magnetic pole are arranged at predetermined positions as the disks 4 and 3 in such a rotating magnetic head assembly. A means for easily manufacturing a product in the same state as it is installed will be explained. Figures 7a to 7f and 8a to 8g show the disk 4 with the main magnetic pole arranged in a predetermined manner, respectively.
First, an example of manufacturing the disc 4 will be described with reference to FIGS. 7a to 7f. The disk 20 shown in FIG. 7a is a disk made of a non-magnetic material with good malleability, such as aluminum, and the aluminum disk 20 has a center hole 30 and positioning holes 31a and 31b. Further, on the surface of the disk 20, thin films 21a, 21b, 22a, 22b, .
is attached. In order to deposit and form the thin films 21a, 21b, . . . of highly magnetically permeable metal material exhibiting the above-mentioned desired pattern on the surface of the disk 20, the necessary steps are performed by, for example, vapor deposition, ion plating, or other suitable means. After depositing a thin film of a highly permeable metal material having a thickness of 100 mL on the entire surface of the disk 20, a predetermined pattern of the thin film is left on the surface of the disk 20, for example, by photo-etching. The center hole 30 of the disk 20 is used as a hole for attaching to the rotating shaft 2 when the disk 20 has main magnetic poles arranged in a predetermined manner to form a completed disk 4. This center hole 30 and positioning holes 31a, 31b are connected to the disk 2.
Thin films 21a, 21b with a predetermined pattern for 0
A mask pattern for forming ... is formed on the disk 20.
It is also used as a reference for attaching the thin films 21a, 21b, . A protective film 32 made of a non-magnetic material with good malleability is deposited on the thin films 21a, 21b, . figure}. Next, disk 2
Punch 33 at least a portion of each thin film at 0
Coining is performed using a coining die 34 equipped with a coining die 34. The progress of the coining process described above is shown in FIGS. 7b and 7c. The punches 33 provided in the coining mold 34 are arranged in such a way that a plurality of punches are used to press each other with precision so that each of the thin films 21a, 21b... deposited on the disk 20 is coined at the same time. The precision coining mold 34 can be manufactured integrally with the punch 33 by applying an ion beam machining method to cemented carbide, for example. Next, the disk 20 coined as described above is cut or polished to the position of line EE in FIG. It is made in such a state that it is oriented in the vertical direction. Figure 7e is
FIG. 7d is a perspective cross-sectional view of the recessed portion shown in FIG. 7d. Through the above-described processing, a disk 20 is obtained in which the surface of the disk 20 shows a predetermined arrangement pattern and the end face of each main magnetic pole is exposed, and the disk 20 is chamfered for introducing the magnetic tape. 3
6, a disk 4 as shown in FIG. 7f is obtained. In order to prevent the thin film from peeling off during the polishing or cutting process performed to obtain the state shown in FIG. 7D from the state shown in FIG. 7C, the disk 20 is formed by coining. It is a desirable embodiment to fill the recess 35 formed in the groove with a plastic material or a glass material. As mentioned above, the reason why a material with good malleability is used for the thin film, the protective film 32, etc. is to prevent the thin film, the protective film 32, etc. from being cut during the coining process using the coining mold 34. It's for a reason. The thickness of the thin film described above is stretched and thinned by the coining process, so the disk 20 is made so that the thickness of the thin film after the coining process becomes the thickness required for the main pole. The thickness of the thin film to be deposited should be determined. The manufacturing method of the disk 4 described with reference to FIGS. 7a to 7f has the following features. (1) Since the plurality of main magnetic poles arranged on the disk 4 are formed by thin films that are simultaneously applied on the disk 20, the thickness and width of each main magnetic pole are extremely uniform, and each thin film Since they are formed by simultaneous patterning, the positions between the thin films are accurate. (2) Disc 2
Since patterning can be performed using the center hole 30 of 0 as a reference, the position of the thin film can be made accurate with respect to the center hole. (3) Since the coining mold 34 can be processed using precision micro-processing technology such as ion beam processing, the position and height of the punch can be uniform,
Further, since the coining process can be performed using the position of the center hole 30 of the disk 20 as a reference, the main magnetic pole obtained by processing the thin film vertically is accurately determined at a predetermined position on the disk 4. Therefore, according to the manufacturing method explained with reference to FIGS. 7a to 7f, it is possible to easily manufacture a large number of disks 4 in which the main magnetic pole is disposed at a predetermined position and has a predetermined cross-sectional shape. can be produced. Next, another method of manufacturing the disk 4 will be described with reference to FIGS. 8a to 8g. In Fig. 8a, 40 is a disc made of a material that is non-magnetic and has excellent plastic working methods, such as aluminum, and 41, 4
1 is a thin film pattern of a highly magnetically permeable metal material deposited on the disk 40. Also, 42, 42...
is a U-shaped hole formed by etching or punching, and this U-shaped hole 4
2, 42... are the disks 4 in a related manner as shown in FIG. 8b with respect to the thin film patterns 41, 41...
Formed to 0. 43 is a center hole, 44 is a positioning hole,
The center hole 43 and the positioning hole 44 may also be formed so as to be formed at the same time as the U-shaped hole 42 described above. The material shown in FIG. 8a is then bent into the state shown in FIG. 8c. In FIG. 8c, the thin film patterns 41, 41, . . . are perpendicular to the surface of the disk 40. In FIG. Since the bending position and angle are important for accurately determining the relative positions of the main magnetic poles, the mold used for the above-mentioned bending process should be made in the same way as for the coining die in the production example mentioned above. Preferably, it is a precision product manufactured using micro-processing technology. FIG. 8d is a side sectional view showing the state of the bent portion due to the above-mentioned processing.
Reference numeral 5 denotes a protective film provided to prevent the thin film pattern 41 from being damaged during the bending process, and this protective film 45 is made of a material that is non-magnetic and has excellent malleability. FIG. 8e shows a process of performing plastic casting or injection molding to reinforce the intermediate product shown in FIG. 8c and to smoothen the board surface. That is, in FIG. 8e, 46 is a lower mold, and 47 is an upper mold, and the intermediate product shown in FIG. 8c is sandwiched and fixed in a cavity 48 formed by combining the lower mold 46 and the upper mold 47. Then gate 47
Inject plastics from a. The center hole 43 of the disk 40 in the intermediate product is held by a protrusion 46a of the lower mold 46, and the positioning hole 44 of the disk 40 is held by a pilot pin (not shown) provided on the lower mold 46. The molded product taken out through the processing step shown in Figure 8e is flattened by cutting or grinding until the end of the bent portion of the disk is exposed, resulting in a cross section as shown in Figure 8f. Disc 4 with
is completed. FIG. 8g is a perspective view of the completed disc 4. Also in the disc 4 shown in FIG. appears in the required sequence pattern within. Next, a method of manufacturing the disk 3 in which auxiliary magnetic poles are arranged in a desired pattern will be described with reference to FIGS. 9a to 9c, FIGS. 10 and 11. The auxiliary magnetic poles to be provided in a desired arrangement pattern on the disk 3 are composed of a magnetic core and a winding wound around the magnetic core, and the cross-sectional area of the magnetic core is hundreds of times larger than the cross-sectional area of the main magnetic pole. The cross-sectional area of the auxiliary magnetic pole is not directly related to the recording wavelength. Therefore, the placement position of the auxiliary magnetic pole on the disk 3 does not require the same level of positional accuracy as is required for the placement position of the main magnetic pole on the disk 4. From this point of view, the manufacturing of the disk 3 is not as precise as the placement position of the main magnetic pole on the disk 4. It is easier than manufacturing. In FIG. 9a, 50 is a disk made using a non-magnetic material, and this disk 50 has holes 51, 51, . . . into which the auxiliary magnetic poles ap are inserted, and also Pins 52 for connecting the windings 7b are provided. The magnetic core 7a of the auxiliary magnetic pole ap is made of a soft magnetic material rod with high magnetic permeability, and a winding 7b is wound around a part of it, and the part where the winding 7b is not present is a disk 50.
The auxiliary magnetic pole ap is held in a predetermined position on the disc 50 by fitting into the hole 51 of the disc 50. The winding 7b of the auxiliary magnetic pole ap is connected to the pin 52 described above. The disk 50 with auxiliary magnetic poles ap held in all the holes 51, 51, respectively, is put into an injection mold or an injection mold consisting of a lower mold 54 and an upper mold 55, as shown in FIG. 9b. When the inside of the mold is filled with plastic 56, the disk 3 is completed with the end face of the auxiliary magnetic pole ap aligned with the disk surface as shown in FIG. 9c. In the manufacturing method of the disk 3 explained with reference to FIGS. 9a to 9c, the auxiliary magnetic pole ap is
Although molding is performed using the hole 51 in a connected state, even if the auxiliary magnetic pole is fixed to the positioning hole provided in the mold and molded, the 9th
It is clear that a disk 3 as shown in Figure c can be manufactured. 10 and 11 are diagrams showing an example of manufacturing the disk 3 when another configuration is used as the auxiliary magnetic pole, FIG. 10 is an exploded perspective view of a part of the disk 3, and FIG. is a perspective view of the finished product. 1st
In Figure 0, 60 is a disk made of non-magnetic material, 61 is a hole into which the magnetic core 62 of the auxiliary magnetic pole ap is inserted, 66 and 67 are pins, and 63 to 65
are the required winding patterns 63a to 65a, respectively.
It is a thin plastic sheet with a coating on it. The winding patterns 63a to 65a described above are spiral patterns formed on a thin plastic sheet using a conductive material, and the patterns can be easily formed by applying a plating method or a photoetching method, for example. can. The winding patterns 63a and 65a have the same spiral pattern, and the winding pattern 64a has a spiral pattern opposite to that of the winding patterns 63a and 65a. The winding patterns 63a to 65a on each of the plastic sheets 63 to 65 are connected to each other from the pin 66 by connecting their starting ends and ending ends in a connection manner as shown by broken lines in the figure.
The pin 67 is electrically connected through the pins 3a to 65a. Therefore, the magnetic core 62 of the auxiliary magnetic pole is inserted into the hole 61 of the disk 60, and both are fixed with adhesive.
A hole 68 provided in the center of the winding patterns 63a to 65a of the plastic sheets 63 to 65 is passed through the magnetic core 62, and the starting end and the ending end of each winding pattern are sequentially electrically connected as required. When stacking and gluing the whole thing in the same manner, the 11th
A disk 3 as shown in the figure is completed. In addition, each plastic sheet 63 to 65 includes
The winding pattern is formed by an arrangement pattern corresponding to the arrangement pattern of the auxiliary magnetic poles on the disk 60, and when the plastic sheets are sequentially stacked, the electrical connection between each winding pattern or In order to facilitate electrical connection between the pin and the end of the winding pattern, holes 69, 69 are provided at the end of the winding of each plastic sheet and through which the pin 67 passes.
It is a desirable implementation to use so-called through holes for the necessary parts. The pins 67, 67 are for connecting the winding provided on one side of the disk 60 to the electric circuit placed on the other side of the disk 60. The disk 3 having the configuration described with reference to FIGS. 10 and 11 is excellent in mass production because it does not require the work of winding a thin wire around the magnetic core 62, and is made of laminated plastic sheets. If a thin sheet without a winding pattern is pasted onto the outermost part of the magnetic tape, it is easy to protect the winding pattern from sliding contact with the magnetic tape. FIG. 12 is an exploded perspective view of the rotating magnetic head assembly shown in FIG.
is a spacer for making the discs 3 and 4 face each other with a predetermined gap, 71 is a printed circuit board, 72 is a cylinder, 70 is a rotating side portion of a rotary transformer, and 2 is a rotating shaft. is already the 6th
As stated in the explanation of the figures. Next, FIGS. 13a and 13b are perspective views of different configurations of the full-width erasing head, respectively. The erasing head shown in FIGS. 13a and 13b is also configured to generate lines of magnetic force perpendicular to the surface of the magnetic tape. The erasing head shown in FIG. 13a is composed of two parts 88a and 88b which clamp the magnetic tape from both sides. In the figure, 88a ₁ is a U-shaped core made of a high permeability magnetic material, and a coil 88a ₂ that generates DC magnetic flux is wound around this core 88a ₁ , and the core 88a ₁ and the winding 88a ₂ The portion 88a is constituted by. Further, the portion 88b is a member 88b ₁ made of a non-magnetic material.
A thin plate 88b ₂ of high magnetic permeability material is deposited on it, incorporating a core 88b ₃ of high magnetic permeability material to reduce the reluctance. core 88b ₃
differs in the structure of its two legs, as shown in _FIG .
The end of the other leg is set back from the end of the thin plate _88b2 . The two parts 88a and 88b constituting the erasing head are spaced apart so that their legs face each other and the gap between them is approximately 100 μm. The magnetic flux generated in one portion 88a concentrates on the end of the thin plate 88b ₂ of the left leg in the portion 88b, and magnetizes the perpendicularly magnetized film in the magnetic tape passing through the gap in that portion to saturation. Erase the DC current. The tip of the right leg in the above-mentioned portion 88b has a large area, so there is little concentration of magnetic flux, and therefore no reversal of the magnetization state in the perpendicularly magnetized film of the magnetic tape occurs in this portion. The erasing head shown in FIG. 13b has a configuration in which a coil 91 is wound around a ring-shaped core 94, and a substantially uniform magnetic field is generated in the gap g formed in the core 94. . From one of the legs of the core 94 constituting the gap g described above, a thin plate 9 made of a highly permeable material supported by a non-magnetic material 92
3 protrudes into the above-mentioned gap g, and the gap between the tip of the thin plate 93 and the end of the other leg is approximately
Since the gap is 100 μm and the magnetic flux is concentrated there, when the magnetic tape passes through the gap, the magnetic tape is saturated and erased. FIG. 14 is a perspective view showing an example of the configuration of an audio recording/reproducing head.
It is composed of two parts: 89b. part 8
9a has a structure in which a coil 89a ₂ is wound around a core 89a ₁ , and a portion 89b has a thin film 8 made of a high magnetic permeability material on an L-shaped member 89b ₁ made of a high magnetic permeability material.
9b ₃ is attached by a support member 89b ₂ made of a non-magnetic material. When the legs of the two parts of the audio recording/reproducing head are opposed to each other, a magnetic tape is run through the gap formed there, and an audio current is passed through the coil _89a2 .
Magnetic flux is concentrated on the thin film _89b3 on the left leg in the figure, and an audio signal is recorded on the magnetic tape. In addition,
The right leg has a large opposing area and does not concentrate magnetic flux, so the magnetic tape is not magnetized during recording. Even during playback, the right leg does not pick up the signal. In the magnetic recording and reproducing apparatus of the present invention, the rotating magnetic head assembly used for recording and reproducing information signals is provided in N parts, each of which is divided into N parts on the circumference of the disks 3 and 4 having a predetermined radius. The total number N of magnetic head sets for recording and reproducing information signals is an even number, and the odd-numbered and even-numbered ones of the N magnetic head sets for recording and reproducing information signals are as follows.
They are so-called opposite azimuths, and furthermore, in the N information signal recording/reproducing magnetic head sets 11a, 12a, etc., there is a reproducing magnetic head set between adjacent ones of the information signal recording/reproducing magnetic head sets 11a, 12a, . . . . Magnetic head sets 11b, 12b, etc. are provided, and each magnetic head set for reproduction has the same azimuth as the previous magnetic head set for recording and reproducing information signals. If so, the tracking control operation can be performed in the following manner during recording and reproduction. First, as shown in FIG. 2, a rotating magnetic head assembly is used in which main magnetic poles belonging to individual magnetic head sets are arranged on a circumference of a specific radius on the surface of a disk 4. The track pitch of the recording trace formed on the magnetic tape when the magnetic tape is placed changes depending on the angle θ, as shown in the above-mentioned equation (3). The reproducing magnetic head set has a magnetic head set of 2π/N·M with respect to the information signal recording/reproducing magnetic head set.
(However, M is a coefficient indicating the positional relationship of the magnetic head set for reproduction with respect to the position of the magnetic head set for recording and reproducing information signals, and N is the number of divisions mentioned above.) Since it follows the immediately preceding magnetic head set for recording and reproducing information signals, the trajectory of the magnetic head set for reproducing is the outer diameter trajectory of the main pole of the immediately preceding set of magnetic heads for recording and reproducing information signals. However, a track pitch deviation of d ₁ =Psinα/M occurs. Therefore, the state of overlap between the main magnetic pole belonging to the reproducing magnetic head set and the recording trace is expressed by the following equation (4). l = d ₃ - _{d 1} = d ₃ = Psinα/M ...(4) {However, d ₃ is the effective pitch at the end of the record trace, and is expressed as d ₃ = d (θ ₂ )} In this way In the rotating magnetic head assembly having the configuration described above, the overlapping state of the main magnetic pole belonging to the reproduction magnetic head set with respect to the recording trace is as follows.
It is modulated by α, that is, the rotation angle θ. Therefore, the signal reproduced from the reproduction magnetic head set, ie, the tracking reference signal, is amplitude-modulated at a frequency as shown by the following equation (A). = No N/60 (Hz) ... (A) (However, No is the number of rotations of the disk 4, and N is the number of divisions.) In the above-mentioned amplitude modulation, for example, in a certain design example, M is set to 2, that is, θ = θ ₂ If l is set to d/2, -15.4% (-
1.5dB). From the above, in a magnetic recording/reproducing apparatus using a rotating magnetic head assembly having the configuration described above, even if the tracking control system is controlled using the signal reproduced by the reproducing magnetic head set as a tracking reference signal, It can be seen that a strictly perfect tracking control operation cannot be performed. However, if the reproducing magnetic head set is offset by _d2 from the information signal recording/reproducing magnetic head set as shown in FIG. 15, and placed behind the information signal recording/reproducing magnetic head set by 2π/MN. The state of overlap between the main magnetic pole belonging to the magnetic head set for reproduction and the recording trace is as follows: l = d ₀ - _{d 2} - _{d 1} = d ₃ - d ₂ - Psinα/M ... (5) Equation (5) Therefore, at θ=θ ₂ , l=
In order to obtain d ₀ /2, the term Psinα/M may be smaller than that in equation (4) due to the existence of the d ₂ term, and therefore, the reproduction magnetic head assembly as in this example is , the degree to which l is modulated by α, that is, θ, becomes small. Therefore, it is possible to use the output signal from the reproduction magnetic head set as a tracking reference signal so that the tracking control operation by the tracking control system can be performed without any trouble. FIG. 16 is a block diagram showing an example configuration of a tracking control circuit when tracking control is performed during recording, and FIG. 17 is a block diagram showing an example configuration of a tracking control circuit when tracking control is performed during reproduction. The tracking control operation during recording will be explained with reference to FIG. In the magnetic recording and reproducing apparatus, in order for the magnetic tape to run at a constant running speed, the magnetic recording and reproducing apparatus shown in FIG. It is necessary that the capstan 85 rotates at a constant speed, that the capstan 85 is a perfect circle with no diameter error or runout, and that the sliding with the magnetic tape is constant. Now, in FIG. 16, 100 is a frequency generator fixed to the rotating shaft of the capstan motor, and this frequency generator 100 outputs an output when the capstan motor 86 is rotating at a normal rotation speed. The frequency value of the vertical synchronizing signal 101 is made to be the same frequency as the vertical synchronizing signal from the vertical synchronizing signal 101. The difference between the frequency of the output signal from the frequency generator 100 and the frequency of the output signal from the vertical synchronization signal source 101 is converted into a voltage by the frequency-voltage converter 102. The output voltage is applied to an amplifier 104 via a low-pass filter 103, and the output of the amplifier 104 is fed back to the capstan motor 86. In FIG. 16, C is a constant bias power supply, but this bias power supply C may be unnecessary depending on the configuration of the tracking control system. In the tracking control system shown in FIG. 16, control operation is performed by a loop consisting of capstan motor 86 → frequency generator 100 → frequency subtractor FS → frequency → voltage converter 102 → low-pass filter 103 → amplifier 104 → capstan motor 86. The capstan motor 86 is rotated at a substantially constant rotation speed, but the capstan motor 86
Even if the magnetic tape rotates at a constant number of rotations, it is clear from the existence of the conditions mentioned above that the magnetic tape does not necessarily run at a constant running speed. In the magnetic recording/reproducing apparatus shown in FIG. 6, even though the configuration of the magnetic tape running path (tape path) is extremely simple, load fluctuations cannot be completely ignored. Then, using a capstan made by normal precision processing,
For example, when performing high-density recording with a track pitch of about 10 μm, it is effective to configure a servo loop that performs tracking control based on the recording traces formed on the magnetic tape. In FIG. 16, TH is a reproducing magnetic head set, and the output from this reproducing magnetic head set represents the running speed of the magnetic tape. That is,
This is because the reproducing magnetic head set is configured in advance so that when the running speed of the magnetic tape is a predetermined value, the reproducing magnetic head set overlaps the recording trace by an amount lo on average. Therefore, if the bias C is set equal to the average output from the reproducing magnetic head set when the reproducing magnetic head set overlaps the recording trace by an amount lo on average, the 16th Tracking control operation is performed by the loop of capstan motor 86 → magnetic head assembly TH for reproduction → compensation circuit 105 → amplifier 106 → comparator 107 → capstan motor 86 in the figure, The head set can form records one after another on the magnetic tape at a constant track pitch. Now, when the tape position changes by X coS ωt, the recording trace recorded on the magnetic tape also changes by
Record the variation of cos ωt. By the way, since the reproducing magnetic head set is behind the information signal recording/reproducing magnetic head set by the time to, this is due to the above-mentioned time delay.
To ride on the curved track of the previous time,
There also occurs a speed error relative to the magnetic tape at the current time t when the reproducing magnetic head set reaches the part of the recording trace where the fluctuation that occurred before t is recorded. Therefore, the amount of superimposed variation Δl on the recording trace of the reproduction magnetic head set is as follows: Δl=X cos ωt−X cos ω(t−to) =−2X sin ω(t−to/2)・sinωto/2 ...(6
) is shown in equation (6), but in equation (6),
If the difference between sin(ωto/2) and ωto/2 is within the allowable value for the servo system, the above-mentioned superimposed variation Δl is expressed by the following equation (7). Δl≒−X ωto sin ω(t−to/2) ……(7) The value of Δl shown in equation (7) is the differential value of the magnetic tape position error X cos ωt −X ω sin ωt, that is, Dead time due to magnetic tape running speed error
Although it is detected in such a way that to/2 and gain to are extra included, since it is controlled in relation to the running speed error of the magnetic tape, the playback magnetic head A servo loop based on the set output is a speed control loop. Considering the dead time to/2 in equation (7), the servo loop can be expanded to a frequency of approximately o=1/10·2/t0. By the way, since to=60/No・N・M (seconds)...(8), in a certain embodiment
o=360Hz, and it is possible to include up to 360Hz in the servo loop. Therefore, low-range running speed errors due to slippage between the capstan and magnetic tape, fluctuations in running load on the magnetic tape, and DC running speed errors such as capstan system errors can be sufficiently suppressed by the servo system. A smooth and accurate running state of the magnetic tape is achieved, and recording traces are formed at accurate track pitches. Note that the compensation circuit 105 in FIG.
This is to make the servo open loop OdB at o. Since the amount that the reproduction magnetic head set superimposes on the recording trace varies depending on the rotation angle θ, as shown by equation (4) mentioned above, the output signal of the reproduction magnetic head set contains ripples. However, in the embodiment described above, the ripple of the output of the reproduction magnetic head set has a fundamental frequency of = No.N/60 = 900Hz, but the servo loop has a
Since it acts as a filter with a low-pass characteristic of o=360 Hz, ripples occurring in the output of the reproduction magnetic head set are sufficiently attenuated and do not cause any problems in practice. Also, the size of the ripple is sufficiently small that it does not substantially affect the response of the servo loop.
It is possible to perform sufficiently good tracking control using the output of the reproduction magnetic head set. In equation (7), dead time and ripple can be reduced by reducing the time to (increasing M, that is, by bringing the reproducing magnetic head set closer to the information signal recording/reproducing magnetic head set). However, since the gain becomes smaller and the S/N of the tracking reference signal decreases, the time to
cannot be made extremely small, and even if the reproducing magnetic head set is placed close to the information signal recording/reproducing magnetic head set, both have their own sizes, so it is not possible to make the magnetic head set extremely small. It is clear that close placement is physically impossible. As shown in FIG. 16, when there is a recording servo system that uses the reproduction signal from the reproduction magnetic head set, the output signal from the frequency generator FG and the vertical synchronization signal source 1 are used.
The above-described speed servo loop performed using the vertical synchronization signal from 01 may have a compensation range small enough to compensate for the bias C drift. Additionally, if the control system is configured as a circuit that does not use bias C,
The state in which the output signal of the frequency generator FG and the vertical synchronization signal from the vertical synchronization signal source 101 exhibit a certain frequency error is the reference state of the tracking control system using the output signal of the reproducing magnetic head set. It will be done. Next, the tracking control operation during reproduction will be explained with reference to the block diagram shown in FIG. 17 and other drawings. In FIG. 17, numerals 4 and 3 are disks in the rotating magnetic head assembly, and H is a magnetic head of the N information signal recording/reproducing magnetic head set configured on the disks 4 and 3 described above. One magnetic head set for recording and reproducing information signals is shown in a state in which information signals are being reproduced from a tape, and TH indicates the magnetic head for reproducing information placed immediately after the magnetic head set H for recording and reproducing information signals. The relationship between the two magnetic head sets is as follows if the above-mentioned magnetic head set H for recording and reproducing information signals has a main sulphate belonging to it, for example, as shown by 12a in FIG. The reproduction magnetic head assembly TH has a main sulphate shown as 12b in FIG. In FIG. 17, 110 is an amplifier that multiplies the output signal of the reproducing magnetic head set by L, 111 is the output signal from the information signal recording/reproducing magnetic head set H,
A differential amplifier 112 and 113 are diodes to which the output signal from the above-mentioned amplifier 110 is given as two inputs, and the diode 112 gives the positive output of the output signal from the above-mentioned differential amplifier 111 to the amplifier 114. The amplifier 114 amplifies the signal applied thereto by a factor of L+1/L-1 and provides the amplified signal to the compensation circuit 115. Furthermore, the diode 113 described above provides the negative output of the output signal from the differential amplifier 111 to the compensation circuit 115.
The output of the compensation circuit 115 is sent to the power amplifier 116.
The signal is amplified and then applied to the capstan motor 86. Now, the principle of construction and operation of the tracking control system shown in FIG. 17 will be explained with reference to FIG. 5 as follows. First, in FIG. 5, T ₂ is considered to be a recorded record trace, and the main magnetic pole 12a belonging to the magnetic head set H for recording and reproducing information signals accurately tracks the record trace T ₂ . The main magnetic pole 12b of the reproducing magnetic head set immediately after the information signal recording/reproducing magnetic head set to which the main magnetic pole 12a belongs is arranged so that 1/L of its effective main pole width rests on the recording trace _T2 . In addition, both main magnetic poles 12 are
a and 12b have the same azimuth so that the information signal of the recording trace T ₂ can be reproduced well, and furthermore, the recording traces T ₃ and T ₁ on both sides of the recording trace T ₂ are It is assumed that recording traces are formed by a magnetic head set for recording and reproducing information signals having a main magnetic pole having an azimuth opposite to that of the magnetic poles 12a and 12b, and that the recording traces are formed by a magnetic head set for recording and reproducing information signals to which the main magnetic pole 12a belongs. Assuming that the reproduction sensitivity of the magnetic head set H for recording and reproducing information is the same as that of the magnetic head set TH for reproduction to which the main magnetic pole 12b belongs, when the signal magnitude of the output signal of the magnetic head set H for recording and reproducing information signals is set to 1. In this case, the magnitude of the output signal of the reproducing magnetic head set TH is 1/L. The magnitude of the output signal from both the magnetic head sets H and TH described above is as follows:
When it deviates in the direction of A in Fig. 5 with respect to the position of
When the recording trace is shifted in a direction opposite to the direction A in FIG. 5 with respect to the positions of both magnetic head sets H and TH, the recording trace changes in the following manner.

[Table] So, the output signal from the magnetic head set TH is
When the multiplied value is subtracted from the output signal from magnetic head set H, if the direction of deviation is A, the above difference becomes (L-1)δ, and if the direction of deviation is -A.
In this case, the difference is -(L+1)δ, and the difference changes in accordance with the direction in which the recording trace deviates from the position of the magnetic head set and the amount of deviation δ. It is clear that in the circuit arrangement shown in FIG. 17, the difference described above is obtained as the output of the differential amplifier 111 described above. Furthermore, the positive output from the differential amplifier 111 is amplified by (L+1)/(L-1) times in the amplifier 114 because both the positive and negative outputs from the differential amplifier 111 are (L+1)δ
This is to make it possible to obtain a linear tracking error signal. In the tracking control circuit during reproduction having the configuration shown in FIG. 17, the tracking error signal is compensated by the compensation circuit 115 as described above, and the power amplifier
By amplifying the power and applying it to the cap motor 86, the running distance of the magnetic tape is controlled so that the tracking deviation δ is eliminated. In this tracking control operation during playback, the tracking deviation δ occurs simultaneously for both magnetic head sets H and TH, so there is no need to consider the dead time that was considered in the tracking control operation during recording as described above. . Furthermore, even when the reproducing magnetic head set TH is tracking the recording trace accurately, the output signal therefrom contains ripples of several dB as shown by equation (4). Therefore, the closed-loop characteristics of the servo system during playback must be sufficiently low at the frequency of = No.N/60 (Hz), but tracking control during recording as described above As in the case of operation, if the loop is closed at 360 Hz, ripples can be sufficiently attenuated. In addition, in order for the tracking control method described above to be applied, the signal form of the information signal to be recorded in the recording trace must have a constant amplitude, such as an FM wave signal, PM wave signal, or PCM signal. It is necessary that it be something. It is also necessary that the amount of deviation X or δ between the magnetic head set and the recorded trace appears as a change in the envelope of the output signal from the magnetic head set. In the above-mentioned tracking control circuit, the change in the envelope of the output signal from the magnetic head set is converted into a direct current and used. Of course, methods such as special recording and special reproduction described in JP-A-55-38608 and JP-A-55-42319 can also be applied to the magnetic recording and reproducing apparatus of the present invention. In this case, since the device of the present invention does not curl the magnetic tape or force the magnetic head set against the magnetic tape, it is easy to quickly run the magnetic tape over a wide range within the vertical blanking period. Therefore, it is easy to apply the above-mentioned special recording and reproduction. In carrying out the present invention, as shown in FIG. 18, the magnetic tape 1 is divided into two recording areas 1U and 1D, and recording is performed in the recording area 1D, which is closer to the center of the disk 4. In this way, there is no need to rewind the magnetic tape after the entire magnetic tape has been recorded, and handling becomes easier. 1S in FIG. 18 may be used as an audio track. In the magnetic recording and reproducing apparatus of the present invention, the length of the television signal to be recorded in one recording trace of the magnetic tape may be arbitrary; for example, one recording trace has an average of 17.5 horizontal scanning periods (17.5H ) signal is recorded, or an 18H television signal is recorded on the record trace of one record,
The 0.5H minute may be recorded twice with adjacent recording traces. For example, in a certain record, 17H
Television signals may be recorded in successive recording traces in such a manner that a television signal of 18H is recorded in the next recording trace, and an 18H television signal is recorded in the next recording trace. In the recording trace where the television signal is recorded, there is no signal in the adjacent recording trace during the 1H period at the beginning or end of the recording trace, so a tracking reference signal cannot be detected in that part. However, the tracking control is not disturbed even by the above condition (the lack of the tracking reference signal mentioned above appears as a component considerably higher than the band of the tracking control system, so it adversely affects the tracking control operation). ) As is clear from the above detailed explanation, the magnetic recording/reproducing apparatus of the present invention further improves high-density recording by the perpendicular magnetization recording method, which facilitates high-density recording, by using a rotating magnetic head assembly. This enabled even higher density recording. In the magnetic recording and reproducing apparatus of the present invention, a main magnetic pole is disposed on one of the two disks, and an auxiliary magnetic pole is provided on the other disk, forming a pair with the above-mentioned main magnetic pole. Arrange the magnetic poles and perform the above 2
The magnetic tape is run at a slow speed using a rotating magnetic head assembly including the two discs, which are opposed to each other with a gap between them, and the magnetic tape is run within the gap. By rotating the disc of the rotating magnetic head assembly at high speed, the magnetic head set can record and reproduce information signals on a magnetic tape, and can also record and reproduce information signals under tracking-controlled conditions. . Furthermore, by using the above-mentioned rotating magnetic head assembly, the running speed of the magnetic tape can be slowed down, and the configuration of the tape path can therefore be simplified.
In addition, in the perpendicular magnetization recording method, the pressing force between the magnetic tape and the magnetic head assembly may be small, so the power for rotating the rotating magnetic head assembly and the power for running the magnetic tape may also be small.
Power loss is also low. In addition, as mentioned above, since the tape path is simple, the tape loading mechanism for the magnetic tape is also simple, which can contribute to achieving miniaturization and cost reduction of the device. In the rotating magnetic head assembly used in the device of the present invention, the magnetic head assembly is constituted by a disk 4 on which the main magnetic pole is arranged and a disk 3 on which the auxiliary magnetic pole is arranged facing each other. However, the plurality of main magnetic poles to be arranged on the disk 4 are
The roundness of the main magnetic pole circle, the spacing between the main magnetic poles, the thickness and width of the main magnetic poles, etc. can be processed and formed at the same time at a specified position on the circumference with a predetermined radius without the need for manual labor, making it possible to achieve extremely precise precision in each of the main magnetic pole circles, the spacing between main magnetic poles, and the thickness and width of the main magnetic poles. It is possible to manufacture a device with high reliability at a low cost, and the disk 3 with the auxiliary magnetic pole can be easily manufactured with high accuracy.Furthermore, it is easy to combine the disk 4 and the disk 3. In addition, since the rotating part of the device has a simple configuration, a highly reliable rotating magnetic head assembly can be easily provided. In addition, since the electrical connection to the winding of the auxiliary magnetic pole described above can be made on the back side of the disc 3, it is easy to configure amplifiers for input/output signals, signal switching circuits, etc. on the back side of the disc 3. You can, and furthermore,
Since the axis of rotation of the rotating magnetic head assembly is parallel to the reel plane of the magnetic tape, the apparatus does not become bulky. A rotating magnetic head assembly in which a large number of magnetic head sets are arranged by the disks 4 and 3 constituting the rotating magnetic head assembly can be easily constructed. The main magnetic pole of can be easily reproduced in large quantities by using the same mask pattern, mold, etc., so it is possible to create a magnetic recording device that maintains good compatibility of recording tape between individual devices. It is easy to mass produce, and by installing a magnetic head set for tracking control so that recording and playback operations are performed under tracking control during recording and playback, even a small amount of magnetic tape can be produced over a long length. It becomes possible to perform time recording and reproducing operations, and it is possible to easily achieve miniaturization of the device. As described above, according to the magnetic recording and reproducing apparatus of the present invention, it is possible to easily provide a magnetic recording and reproducing apparatus that is capable of recording and reproducing at a much higher density than conventional magnetic recording and reproducing apparatuses.

[Brief explanation of the drawing]

FIG. 1 is a perspective view for explaining the schematic configuration of the main parts of a rotating magnetic head assembly used in the magnetic recording/reproducing apparatus of the present invention, and FIG. 2 is a relationship between the disk on which the main magnetic pole is arranged and the magnetic tape. Front view showing the aspect, 3rd
18 are perspective views showing the relationship between the magnetic head assembly and the magnetic tape, FIG. 4 is a diagram showing the rotation locus drawn by the main magnetic pole in the recording area, and FIGS. 5 and 15 are the main magnetic pole and the auxiliary magnetic pole. Explanatory diagram of the rotation locus with the magnetic pole, No. 6
The figure is a plan view of an example configuration of the magnetic recording/reproducing apparatus of the present invention, Figures 7a to 7f and 8a to 8g are diagrams for explaining each step of the manufacturing method of the disk 4, and Figure 9 Figures a to c are explanatory diagrams of each process in the manufacturing method of the disc 3, Figure 10 is an exploded perspective view of a part of an example embodiment of the disc 3, Figure 11 is a perspective view of the same as the above, and Figure 12 is an exploded perspective view of a part of the disc 3.
Figure 13 is an exploded perspective view of the rotating magnetic head assembly.
Figures a and b are perspective views of the erasing head, Figure 14 is a perspective view of the audio recording/reproducing head, Figure 16 is a block diagram of the tracking control circuit during recording, and Figure 17 is a block diagram of the tracking control circuit during playback. It is a diagram. 1... Magnetic tape, 2... Rotating shaft, 3, 4...
Disk, 5...Support, 6...Thin film, 11a, 11
b, 12a, 12b, mp...main magnetic pole, ap...auxiliary magnetic pole, 7a...magnetic core, 7b...winding, H...magnetic head assembly for recording and reproducing information signals, TH...magnetic head assembly for reproducing, 86...capstan motor, 1
00... Frequency generator, 101... Vertical synchronization signal source, 102... Frequency voltage converter, 103... Low pass filter, 104, 106, 110, 11
4,116...Amplifier, 105,115...Compensation circuit, 111...Differential amplifier, 112,113...
…diode.

Claims (1)

[Claims] 1. In a tape-shaped magnetic recording medium having a magnetic layer configured to generate residual magnetization in a direction perpendicular to the tape surface, a soft magnetic material is provided on the tape surface side of the magnetic layer side. A thin film-like main magnetic pole made of aluminum is disposed so that one end face thereof faces the tape surface, and a thin film-like main magnetic pole made of Also, an auxiliary magnetic pole made by winding a magnetic core having a large cross-sectional area is arranged so that the end face of the magnetic core faces the end face of the main magnetic pole, and the pair of the main magnetic pole and the auxiliary magnetic pole is Information signals are recorded in accordance with a magnetic recording and reproducing method in which information signals are recorded on a traveling magnetic recording medium and reproduced from the magnetic recording medium by a magnetic head set configured by a magnetic recording medium. A magnetic recording and reproducing device for recording and reproducing, which is arranged facing each other at a distance that allows a traveling magnetic recording medium to pass therethrough, and which has a radius larger than the tape width of the magnetic recording medium described above.
The two discs are rotated at the same predetermined rotational speed, and there are individual discs on the circumference corresponding to a predetermined radial position on one of the two discs. The individual main magnetic poles belonging to the magnetic head set are arranged at predetermined intervals; The auxiliary magnetic poles, which are to be paired with each individual main magnetic pole provided on the disc to form each individual magnetic head set, are arranged to individually oppose each individual main magnetic pole provided on one of the discs. The two disks constitute a rotating magnetic head assembly, and the magnetic layer of the magnetic recording medium is placed on one of the disks of the rotating magnetic head assembly. By causing the magnetic recording medium to travel in contact with the end faces of successive main magnetic poles, a predetermined rotation locus is drawn on the magnetic recording medium by successive sets of magnetic heads in the rotating magnetic head assembly; A magnetic recording and reproducing device for magnetically recording and reproducing information signals. 2. Claim 1 uses a rotating magnetic head assembly in which the end face of the main magnetic pole and the end face of the auxiliary magnetic pole are made to coincide with the surface of the disk to which they are attached. magnetic recording and reproducing device. 3. Magnetic head sets for recording and reproducing information signals are arranged at equal angles on a disk, and when a certain magnetic head set reaches the information signal recording area on the magnetic recording medium, that magnetic head set A patent claim using a rotating magnetic head assembly in which the arrangement radius of the magnetic head set on a disk is determined so that the magnetic head set preceding the magnetic head set is located at a predetermined position within the information signal recording area of the magnetic recording medium. The magnetic recording and reproducing device according to scope 1. 4. A tape-shaped magnetic recording medium having a magnetic layer such that residual magnetization occurs in a direction perpendicular to the tape surface is arranged facing each other at a distance that allows the tape-shaped magnetic recording medium to run through it, and the magnetic recording medium described above is Two discs having radii larger than the tape width are rotated at the same predetermined rotational speed, and also correspond to a predetermined radial position on one of the two discs described above. On the circumference of the circle,
The thin film main magnetic poles belonging to the individual information signal recording and reproducing magnetic head sets in the information signal recording and reproducing head set group are located at predetermined intervals, and the thin film main magnetic poles The magnetic head assemblies for recording and reproducing information signals are provided in such a manner that the longitudinal direction of the cross section thereof is inclined in opposite directions by a predetermined angle with respect to the radial direction of the disk, and the magnetic head assembly group for recording and reproducing information signals is provided. Between adjacent sets of magnetic heads for recording and reproducing information signals belonging to the above-described set of magnetic heads for recording and reproducing information signals, the preceding information is located at a position on the radius that is approximately the same as the position on the radius where the set of magnetic heads for recording and reproducing information signals described above is located. The main magnetic pole of the magnetic head assembly for reproduction is provided with the same inclination aspect as that of the main magnetic pole in the magnetic head assembly for signal recording and reproduction. In this case, auxiliary magnetic poles, which are to be paired with each individual main magnetic pole provided on the above-mentioned one disk to constitute each individual magnetic head, are provided on each of the individual main magnetic poles provided on the above-mentioned one disk. such as those arranged in such a manner that they individually face the magnetic poles,
The two discs constitute a rotating magnetic head assembly, and the magnetic layer of the magnetic recording medium is brought into contact with the end face of the main magnetic poles on one of the discs of the rotating magnetic head assembly. By running the magnetic recording medium, a predetermined rotation locus is drawn on the magnetic recording medium by successive magnetic head sets in the rotating magnetic head assembly, and information signals of the magnetic head set group for information signal recording and reproduction are drawn. A magnetic recording and reproducing apparatus is configured to magnetically record and reproduce information signals using a recording and reproducing magnetic head set. 5. A tape-shaped magnetic recording medium having a magnetic layer such that residual magnetization occurs in a direction perpendicular to the tape surface is arranged facing each other at a distance that allows the tape-shaped magnetic recording medium to run through the magnetic recording medium, and the above-mentioned magnetic recording medium is Two discs having radii larger than the tape width are rotated at the same predetermined rotational speed, and also correspond to a predetermined radial position on one of the two discs described above. On the circumference of the circle,
The thin film main magnetic poles belonging to the individual information signal recording and reproducing magnetic head sets in the information signal recording/reproducing magnetic head set group are located at predetermined intervals apart from each other, and in the same order as the thin film main poles. The magnetic heads are provided in such a manner that their longitudinal directions in cross section are inclined in opposite directions alternately by a predetermined angle with respect to the radial direction of the disk, and the above-mentioned magnetic head assembly for recording and reproducing information signals is provided. Between adjacent sets of magnetic heads for recording and reproducing information signals belonging to the group, and at positions on the same radius as the above-mentioned set of magnetic heads for recording and reproducing information signals, The main magnetic pole of the magnetic head assembly for reproduction is provided with the same inclination aspect as that of the main magnetic pole in the magnetic head assembly for recording and reproduction of information signals. The other one has auxiliary magnetic poles that are to form pairs with the individual main magnetic poles provided on the one disk described above to form each individual magnetic head set, and each of the individual magnetic poles provided on the one disk described above is The two disks constitute a rotating magnetic head assembly, and the magnetic layer of the magnetic recording medium is arranged so as to face the main magnetic pole of the disk. By running the magnetic recording medium in contact with the end faces of the main magnetic poles on one disk of the head assembly, the magnetic recording medium is placed in a predetermined position on the magnetic recording medium by the successive sets of magnetic heads in the rotating magnetic head assembly. The information signal is magnetically recorded and reproduced by the information signal recording and reproducing magnetic head set of the information signal recording and reproducing magnetic head set group. When forming recording traces at predetermined recording trace intervals on a magnetic recording medium by successive magnetic head sets for recording and reproducing information signals in a group of magnetic head sets,
The rotating magnetic head assembly is adjusted so that the reproducing magnetic head set located in the middle of the above-mentioned sequential information signal recording/reproducing magnetic head sets rides a predetermined distance on the recorded trace of the same azimuth. As a signal for controlling the running speed of the magnetic recording medium with respect to the rotational speed of The low frequency component of the speed difference signal between the signal generated according to the rotation speed and the second reference signal is determined by determining that the speed difference signal between the first reference signal and the second reference signal is small. A magnetic recording and reproducing apparatus is configured such that recording traces recorded and formed on a magnetic recording medium by a set of magnetic heads for recording and reproducing information signals are set at predetermined recording trace intervals. 6. The magnetic recording and reproducing apparatus according to claim 5, wherein the signal is fed back to the drive source of the magnetic recording medium so that the speed difference signal with respect to the second reference signal becomes small. 7. A tape-shaped magnetic recording medium having a magnetic layer such that residual magnetization occurs in a direction perpendicular to the tape surface is arranged facing each other at a distance that allows the tape-shaped magnetic recording medium to pass therethrough, and the above-mentioned magnetic recording medium Two discs having radii larger than the tape width are rotated at the same predetermined rotational speed, and also correspond to a predetermined radial position on one of the two discs described above. On the circumference of the circle,
The thin film main magnetic poles belonging to the individual information signal recording and reproducing magnetic head sets in the information signal recording and reproducing head set group are located at predetermined intervals, and the thin film main magnetic poles The magnetic head assemblies for recording and reproducing information signals are provided in such a manner that the longitudinal direction of the cross section thereof is inclined in opposite directions by a predetermined angle with respect to the radial direction of the disk, and the magnetic head assembly group for recording and reproducing information signals is provided. Between adjacent sets of magnetic heads for recording and reproducing information signals belonging to the above-described set of magnetic heads for recording and reproducing information signals, the preceding information is located at a position on the radius that is approximately the same as the position on the radius where the set of magnetic heads for recording and reproducing information signals described above is located. The main magnetic pole of the magnetic head assembly for reproduction is provided with the same inclination aspect as that of the main magnetic pole in the magnetic head assembly for signal recording and reproduction. In this case, auxiliary magnetic poles, which are to be paired with each individual main magnetic pole provided on the above-mentioned one disk to constitute each individual magnetic head set, are provided on each of the individual main magnetic poles provided on the above-mentioned one disk. A rotating magnetic head assembly is constituted by the two disks, which are arranged so as to face the main magnetic pole individually, and the magnetic layer of the magnetic recording medium is connected to the rotating magnetic head. By running the magnetic recording medium in contact with the end faces of the main magnetic poles on one of the discs of the assembly, the sequential magnetic head sets in the rotating magnetic head assembly generate a predetermined position on the magnetic recording medium. Make sure that the rotation trajectory is drawn,
The information signal recording and reproducing magnetic head set of the information signal recording and reproducing magnetic head set is configured to perform magnetic recording and reproducing of the information signal, and the information signal recording and reproducing magnetic head set group sequentially records and reproduces information. While the reproducing magnetic head set is reproducing the information signal while accurately tracing the recording trace formed on the magnetic recording medium, the reproducing magnetic head set is reproducing the information signal while accurately tracing the recording trace formed on the magnetic recording medium. te1/
A signal obtained by subtracting a signal obtained by subtracting a signal obtained by multiplying the amplitude of the reproduction signal of the magnetic head group for reproduction by L from the amplitude of the reproduction signal of the magnetic head group for recording and reproducing information signals is obtained. When the signal is positive, a control signal that is (L+1)/(L-1) times larger than when it is negative is generated, and is fed back to the drive source of the magnetic recording medium so that the above subtracted signal becomes smaller, and the information is A magnetic recording and reproducing device in which a set of magnetic heads for signal recording and reproducing accurately traces recorded tracks on a magnetic recording medium.