JP2004087008A - Method for manufacturing rotary magnetic head, and rotary magnetic head manufactured by the method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a method for manufacturing a rotary magnetic head by which two magnetic heads can be attached directly to a rotary cylinder in a state of matching there gap heights, and the need for a base, fixing screws and a height adjusting screw can be eliminated, and to provide a rotary magnetic head manufactured by the method. <P>SOLUTION: Two same core bars 30 connected in the direction along parts (junction parts 32) in which a plurality of parts (parts position A, B, C, D) becoming a head core are gap are made. These two core bars 30 are arranged in the direction of upward and downward respectively, a direction of the junction part 32 is tilted for the vertical direction to a cutting line L, a line Q connecting an end point P and an end point P' of the both junction parts 32 is made parallel with the cutting line L. Two kinds of Head cores in which directions of gaps are opposite each other and height from a cutting surface to the gap are same are made by cutting simultaneously these two core bars 30 by the cutting line L. Two kinds of magnetic heads made from these head core are stuck to a rotation cylinder. Thereby, a height adjusting screw or the like are not required. <P>COPYRIGHT: (C)2004,JPO

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a method for manufacturing a rotating magnetic head for recording / reproducing information on a recording medium such as a magnetic tape and a rotating magnetic head manufactured by the method.
[0002]
[Prior art]
2. Description of the Related Art Conventionally, a magnetic recording / reproducing device such as a VCR (Video Cassette Recorder) has a rotary magnetic head for magnetically recording / reproducing information on a magnetic tape. The general configuration of this rotary magnetic head is shown in FIGS. 9 and 10 (a) and 10 (b). The rotating magnetic head 70 includes a fixed cylinder 71, a rotating cylinder 74 driven to rotate by a rotation driving mechanism (not shown) via a shaft 72 and a bearing 73, and two magnetic heads 80 a and 80 b attached to the rotating cylinder 74. And The two magnetic heads 80a, 80b are attached to metal bases 91a, 91b, and the bases 91a, 91b are screwed to the rotation cylinder 74 with mounting screws 92a, 92b, thereby rotating the rotation axis of the rotation cylinder 74. It is attached at a position 180 ° opposite to the center.
[0003]
The magnetic head 80b has a configuration in which a coil winding 82b is applied to a head core 81b. The head core 81b has a gap 84b for generating a magnetic flux at a tip 83b, and the tip 83b is fixed to the fixed cylinder 71 and the rotating cylinder. It protrudes from the outer peripheral surface of the cylinder 74 by approximately 40 [μm]. The magnetic head 80a has the same configuration. The mounting height of these two magnetic heads 80a, 80b is adjusted by pressing the bases 91a, 91b with the height adjusting screws 97a, 97b. The height adjusting screws 97a and 97b press the bases 91a and 91b in a direction opposite to the direction in which the mounting screws 92a and 92b screw the bases 91a and 91b. The two magnetic heads 80a, 80b are connected to printed boards 94a, 94b by lead wires 93a, 93b, and the printed boards 94a, 94b are connected to a rotary transformer 96 by lead wires 95a, 95b.
[0004]
In this type of rotating magnetic head 70, the outer peripheral surfaces of the fixed cylinder 71 and the rotating cylinder 74 are used as the running surface of the magnetic tape, and the rotating direction of the rotating cylinder 74 is inclined with respect to the running direction of the magnetic tape, so that the magnetic head 80a, Magnetic recording / reproducing is performed by a so-called helical scan method in which the laser beam 80b is scanned obliquely. That is, when a magnetic recording operation is performed by the rotating magnetic head 70, the two magnetic heads 80a and 80b slide on the magnetic tape alternately and obliquely. Recording tracks by the magnetic head 80b are formed alternately and obliquely.
[0005]
By the way, as shown in FIGS. 11A and 11B, in order to avoid crosstalk (interference) from an adjacent track, this type of rotating magnetic head 70 has a gap 84a of the head core 81a and a gap 84b of the head core 81b. Are inclined by a predetermined angle (azimuth angle) θ in directions opposite to each other. In addition, the height H11 from the bottom surface of the base 91a of the head core 81a to the effective core width and the height H12 from the bottom surface of the base 91b of the head core 81b to the effective core width have different dimensions in terms of processing accuracy. . Therefore, the heights of the magnetic heads 80a and 80b are adjusted by the height adjusting screws 97a and 97b, and the heights of the gaps 84a and 84b are adjusted.
[0006]
The magnetic heads 80a and 80b of this type of rotating magnetic head 70 are prepared by the following method and attached to the rotating cylinder 74. First, the head cores 81a and 81b are created. As shown in FIGS. 12A, 12B, and 12C, the head core 81a has a structure in which a C-type core 86a made of single crystal ferrite and an I-type core 87a are bonded by a glass material 88 via a gap 84a. It has become. The head core 81a is formed by first bonding a C-type core bar in which a plurality of C-type cores 86 are arranged in a row and an I-type core bar in which a plurality of I-type cores 87 are arranged in a row by glass bonding. A head bar is prepared by arranging the head cores 81a in a line. At this time, a thin film serving as a gap 84a is formed on the bonding surface of the C-type core bar and the I-type core bar by sputtering. Then, the core bar is sliced and cut by a wire saw at a predetermined angle with respect to the bonding surface in units of the thickness of the head core 81a. Thus, the head core 81a having the structure shown in FIG. 12 is created.
[0007]
The gap 84b of the head core 81b is inclined in directions opposite to the gap 84a of the head core 81a as described above. Therefore, the head core 81b is formed by cutting the core bar at an angle opposite to the cutting angle of the head core 81a, separately from the cutting of the head core 81a.
[0008]
Next, as shown in FIG. 13, the head core 81a thus formed is bonded to the tip of a metal base 91a to which a printed circuit board 94a is attached, using an adhesive 98. Next, the tip portion 83a of the head core 81a is polished so that the tip portion 83 of the head core 81a has a curved surface with a curvature r in the thickness direction called a small radius as shown in FIGS. 14 (a), (b) and (c). To finish. This polishing is performed with the base 91a held by a holder (not shown). When the polishing is completed, the coil winding 82a is applied to the head core 81a while the base 91a is held by the holder, as shown in FIG. Then, as shown in FIGS. 16A and 16B, the lead wires 93a of the coil windings 82a are soldered to the copper foil portions 99a of the printed circuit board 94a to complete the magnetic head 80a. The magnetic head 80b is similarly created. After that, various characteristics such as inductance, output characteristics, and bearings are inspected, and the magnetic heads 80a and 80b are completed.
[0009]
Next, the bases 91a and 91b of the magnetic heads 80a and 80b thus formed are screwed to the rotary cylinder 74 with mounting screws 92a and 92b. Then, the bases 91a and 91b are pressed by the height adjusting screws 97a and 97b, and the heights of the gaps 84a and 84b are adjusted to be the same. Finally, the lead wires 95a and 95b of the rotary transformer 96 are soldered to the printed circuit boards 94a and 94b. Thus, the attachment of the magnetic heads 80a and 80b to the rotary cylinder 74 is completed.
[0010]
On the other hand, a rotary cylinder is known in which two magnetic heads are directly assembled to an upper cylinder, and components such as a head base, a head base fixing screw, and a magnetic head adjusting screw are unnecessary (for example, Japanese Patent Application Laid-Open No. Hei 6 (1999)). -208711). Also, regarding the magnetic head, when forming the contact surface of the magnetic head so that a reliable contact state can be obtained between the magnetic head and the magnetic tape, the contact surface is formed in the same state as when the magnetic head is used. Polishing is known (see, for example, JP-A-10-340421). Also, regarding the head mounting mechanism of the rotary head device, an adhesive is applied between the rotary drum and the head base so that the height position adjustment of the magnetic head can be performed with a simple operation and with high accuracy. It is known that the head base is moved in the radial direction of the rotating drum and tilted so that the protrusion amount and height of the magnetic head are adjusted before the agent is hardened (for example, see Japanese Patent Application Laid-Open No. H05-1993). No. 28448). In addition, regarding the jig for attaching the magnetic head to the tape lap polishing device, it has a mechanism for adjusting the tilt of the head and a mechanism for adjusting the position so that fine adjustment can be performed while checking the finished state of the head and processing can be performed accurately. A device using an elastic fixing mechanism for fixing a head mounting unit and a base supporting the unit is known (for example, see Japanese Utility Model Laid-Open No. 3-2412). Further, with respect to the polishing apparatus, a cylindrical jig having slits above and below a magnetic head protruding hole, and a polishing tape at a position corresponding to the slit so that the processing size of the arc shape in a specific direction at the tip of the magnetic head can be adjusted. A device having a nozzle for blowing air to press a cylindrical jig is known (for example, see Japanese Utility Model Application Laid-Open No. 3-130353).
[0011]
[Problems to be solved by the invention]
However, in the conventional rotary magnetic head described above, the bases 91a and 91b and the mounting screws 92a and 92b are used for mounting the magnetic heads 80a and 80b to the rotary cylinder 74, and the height of the gap 84a and the height of the gap 84b are used. Height adjustment screws 97a and 97b have been used to match the height. For this reason, the number of parts was large and the product was expensive.
[0012]
Therefore, the two head cores 81a and 81b are made to have the same dimensions except that the inclinations of the gaps 84a and 84b are different, and the head cores 81a and 81b are directly attached at positions 180 ° opposite to each other with the rotation axis of the rotation cylinder 74 interposed therebetween. It is possible. By doing so, the height from the mounting surface to the gaps 84a, 84b is the same as the head cores 81a, 81b merely mounted on the rotary cylinder 74, so that the bases 91a, 91b, the mounting screws 92a, 92b, and the height The adjustment screws 97a and 97b become unnecessary, and the number of parts can be reduced.
[0013]
However, in the conventional method for producing the head cores 81a and 81b, since the head core 81a and the head core 81b were separately cut out, the two head cores 81a and 81b could not be produced in the same size due to processing accuracy. Therefore, even if the head cores 81a and 81b are directly attached to the rotary cylinder 74, the heights of the gaps 84a and 84b cannot be made equal.
[0014]
Although the above-mentioned Japanese Patent Application Laid-Open No. 6-208711 describes a structure in which two magnetic heads are directly assembled to the upper cylinder, the height adjustment of the gap between the two magnetic heads and the same height of the gap are performed. There is no disclosure of a method for producing two magnetic heads that satisfies the above conditions, and the above-described problem cannot be solved even if the disclosed content is applied thereto. Further, even if the contents disclosed in JP-A-10-340421, JP-A-5-28448, JP-A-3-2412, and JP-A-3-130353 are applied, the above-described problem is solved. I can't.
[0015]
The present invention has been made in order to solve the above-mentioned problems, and two magnetic heads can be directly mounted on a rotating cylinder with the height of a gap adjusted, and a base, a mounting screw, and a height adjusting screw are provided. It is an object of the present invention to provide a method of manufacturing a rotating magnetic head which can be made unnecessary and a rotating magnetic head manufactured by the method.
[0016]
[Means for Solving the Problems]
In order to achieve the above object, according to the first aspect of the present invention, there are provided two types of magnetic head cores in which a gap for generating magnetic flux is formed by inclining two types of magnetic head cores inclined at a predetermined angle in directions opposite to each other. A method of manufacturing a rotary magnetic head, comprising: preparing a head and mounting these two types of magnetic heads at a position 180 ° opposite to an outer peripheral surface of a rotary cylinder serving as a running surface of a magnetic tape with a rotation axis interposed therebetween, A core bar creating step of creating at least two identical core bars in which a plurality of core bars are connected in a row in a direction along the gap portion; and turning the two core bars created in the core bar creating step upside down. Orientation, the corresponding positions of both gaps are aligned and fixed obliquely at the predetermined angle, and these two core bars are fixed at the predetermined angle. A core cutting step of cutting out the two types of magnetic head cores by cutting out the magnetic head cores in the unit direction in a thickness direction, holding the magnetic head cores cut out in the core cutting step by a jig, and cutting the tip of the magnetic head cores. Polishing and applying a coil winding to the magnetic head core to produce the two types of magnetic heads; and bonding the two types of magnetic heads produced in the head producing process directly to the rotary cylinder. Head mounting step.
[0017]
In this manufacturing method, two types of magnetic head cores in which gaps are inclined in directions opposite to each other are formed from two identical core bars in which a plurality of magnetic head cores are connected in a row in a direction along the gap. It is cut out and created. At this time, since the two core bars are cut out obliquely with the two core bars turned upside down, the two kinds of cut out magnetic head cores are inclined at a predetermined angle in directions in which the gaps are opposite to each other. Further, since the two core bars are cut out so that the positions corresponding to both gaps are aligned in the cutout direction, the two types of cutout magnetic head cores have the same height of the gap with respect to the cutout surface. These two types of magnetic head cores are formed into two types of magnetic heads by polishing the tip and applying a coil winding. The two types of magnetic heads are rotated by using the cutout surface of the magnetic head core as an adhesive surface. Is directly bonded and attached at a position 180 ° opposite to the rotating shaft. As a result, the two magnetic heads mounted on the rotary cylinder have the same height position of the gap with respect to the adhesive surface to the rotary cylinder.
[0018]
According to a second aspect of the present invention, two types of magnetic heads are formed by applying coil windings to two types of magnetic head cores in which gaps for generating magnetic flux are inclined at a predetermined angle in directions opposite to each other, thereby forming one or more pairs of magnetic heads. The method of manufacturing a rotating magnetic head, wherein one or more pairs of the two types of magnetic heads are mounted on the outer peripheral surface of a rotating cylinder serving as a running surface of a magnetic tape at symmetrical positions around a rotation axis. A core bar creation step of creating a pair of at least two core bars in which a portion serving as a head core is connected in a row, and a pair or two or more pairs of the two core bars created in the core bar creation step. The corresponding positions of the gaps are aligned and fixed, and one or more pairs of these core bars are cut out in units of the thickness of one magnetic head core to form the two types of core bars. A core cutting step of forming one or more pairs of magnetic head cores, and a head mounting step of directly mounting one or more pairs of magnetic heads formed from the magnetic head cores cut out in the core cutting step to the rotary cylinder. Things.
[0019]
In this manufacturing method, a pair or a plurality of pairs of two types of magnetic head cores whose gaps are inclined in directions opposite to each other are cut out from one or a plurality of pairs of core bars in which a portion to be a magnetic head core is connected in a row. Created. At this time, since one or more pairs of core bars are cut out at once by adjusting the corresponding positions of the respective gaps, the cut out one or more pairs of magnetic head cores are positioned at the height of the gap with respect to the cut surface. Will be the same. Then, one or more pairs of magnetic heads formed by applying coil windings to these magnetic head cores are directly positioned at positions symmetrical about the rotation axis of the rotary cylinder with the cut surface of the magnetic head core as a mounting surface. It is attached. As a result, one or more pairs of magnetic heads mounted on the rotary cylinder have the same height position of the gap with respect to the mounting surface on the rotary cylinder.
[0020]
According to a third aspect of the present invention, in the method of manufacturing a rotating magnetic head according to the second aspect, the core bar forming step includes a step of forming a plurality of at least two magnetic head cores connected in a line in a direction along a gap portion. In the core cutting step, the two core bars created in the core bar creating step are turned upside down, the corresponding positions of both gaps are aligned and fixed, and these two core bars are fixed. Is cut out at a predetermined angle in an oblique direction in units of the thickness of one magnetic head core to produce two types of magnetic head cores.
[0021]
In this manufacturing method, two identical core bars are cut out obliquely with the same core bar turned upside down, so that the two cut out magnetic head cores are two types in which the gaps are inclined at predetermined angles in directions opposite to each other.
[0022]
A fourth aspect of the present invention is a rotary magnetic head manufactured by the method of manufacturing a rotary magnetic head according to any one of the first to third aspects.
[0023]
BEST MODE FOR CARRYING OUT THE INVENTION
Hereinafter, embodiments of the present invention will be described with reference to the drawings. In FIG. 1, a rotary magnetic head 1 is built in a magnetic recording / reproducing device (not shown) such as a VCR (Video Cassette Recorder) and magnetically records / reproduces information on a magnetic tape. The rotating magnetic head 1 includes a fixed cylinder 2 and a rotating cylinder 3 whose outer peripheral surfaces are running surfaces of a magnetic tape, CH1 (channel 1) for magnetically recording / reproducing information on a magnetic tape, and CH2 (channel 2). ) And two magnetic heads 4a and 4b, which are called 2HD Type.
[0024]
The fixed cylinder 2 is formed in a cylindrical shape, and is fixed to the magnetic recording / reproducing apparatus main body. The rotary cylinder 3 is formed in a cylindrical shape having the same radius as the fixed cylinder 2, and its outer peripheral surface is aligned with the outer peripheral surface of the fixed cylinder 2. And is rotatably supported via bearings 8. The rotary cylinder 3 is driven to rotate in a circumferential direction by a rotary drive mechanism (not shown) with the outer peripheral surface of the rotary cylinder 3 and the outer peripheral surface of the fixed cylinder 2 aligned with the shaft 7 as a rotation axis.
[0025]
The magnetic head 4a for CH1 includes a head core 5a and a coil winding 6a wound around the head core 5a. The magnetic head 4b for CH2, like the magnetic head 4a, also includes a head core 5b and a coil winding 6b. When the two magnetic heads 4a and 4b are opposed to each other by 180 degrees about the rotation axis of the rotary cylinder 3, the tips of the head cores 5a and 5b project approximately 40 μm from the outer peripheral surfaces of the fixed cylinder 2 and the rotary cylinder 3. In this state, the head cores 5a and 5b are attached directly to the bottom surface of the rotary cylinder 3 with an adhesive. These two magnetic heads 4a, 4b are connected to printed boards 10a, 10b attached to the rotary cylinder 3 by leads 9a, 9b, and the printed boards 10a, 10b are connected to the rotary transformer 12 by leads 11a, 11b. Is connected to
[0026]
As shown in FIGS. 2A, 2B, and 2C, the head core 5a for CH1 has a tip portion 21a having a curved surface with a curvature R, and has a gap 22a at the center of the tip portion 21a. It has a hole 23a and a groove 24a, 25a for winding the coil winding 6a. The head core 5a has a structure in which a C-type core 26a made of single crystal ferrite and an I-type core 27a are bonded to each other via a gap 22a by glass bonding using a glass material 28. The gap 22a is formed to have an azimuth angle of + 6 ° ± 10 ′ with respect to a direction perpendicular to the bottom surface (adhesion surface to the rotary cylinder 3) 29a of the head core 5a. The dimensions of the head core 5a are, for example, such that the gap reference height H1 from the bottom surface 29a is 0.065 [mm], the track width Tw is 0.026 [mm], and the core width Cw is 0.135 [mm]. Have been.
[0027]
As shown in FIGS. 3A, 3B, and 3C, the head core 5b for CH2 has a gap 22b at the distal end 21b and a hole 23b and grooves 24b and 25b, like the head core 5a. The C-shaped core 26b and the I-shaped core 27b are bonded together via a gap 22b. However, the gap 22b has an azimuth angle of −6 ° ± 10 ′ with respect to a direction perpendicular to the bottom surface (adhesion surface to the rotating cylinder 3) 29b of the head core 5a in a direction opposite to the gap of the head core 5a. Is formed. The gap reference height H1 and the core width Cw are formed to have the same dimensions as the head core 5a, and the track width Tw is formed to be different from the head core 5a in terms of processing accuracy, for example, 0.031 [mm]. ]. Note that the difference between the dimensions of the track width Tw is within an allowable range that does not affect magnetic recording / reproduction. The method of forming these head cores 5a and 5b will be described later.
[0028]
In the rotating magnetic head 1 having such a configuration, when the rotating cylinder 3 is driven to rotate, the two magnetic heads 4 a and 4 b make a circumferential motion about the rotation axis of the rotating cylinder 3. The two magnetic heads 4a and 4b alternately scan the magnetic tape obliquely (helical scan) by causing the magnetic tape to run obliquely on the outer peripheral surfaces of the fixed cylinder 2 and the rotating cylinder 3, thereby forming a magnetic tape. On the other hand, magnetic recording / reproduction is performed.
[0029]
According to the rotary magnetic head 1 having such a configuration, the magnetic head 4a and the magnetic head 4b are inclined between the recording tracks adjacent to each other on the magnetic tape because the gaps 22a and 22b are inclined in directions opposite to each other. Magnetic recording / reproduction is performed without causing interference. The magnetic heads 4a and 4b have the same gap reference height H1 from the bottom surfaces 29a and 29b of the head cores 5a and 5b, and the bottom surfaces 29a and 29b of the head cores 5a and 5b are directly bonded to the rotary cylinder 3. I have. For this reason, the heights of the gaps 22a and 22b when the magnetic heads 4a and 4b are mounted on the rotary cylinder 3 are the same, and magnetic recording / reproduction is performed with high accuracy.
[0030]
Next, a method of manufacturing the rotary magnetic head 1 having the above configuration will be described. The method of manufacturing the rotary magnetic head 1 includes (1) a core bar forming step of forming a core bar as a basis of the head cores 5a and 5b, (2) a core cutting step of cutting out the head cores 5a and 5b from the core bar, and (3) a cut-out step. And (4) a head mounting step of mounting the magnetic heads 4a and 4b to the rotary cylinder 3.
[0031]
First, in the core bar forming step, two core bars 30 are formed as bases of the head cores 5a and 5b as shown in FIG. The core bar 30 has a structure in which a C-shaped core bar 36 and an I-shaped core bar 37 are bonded together at a plurality of joints 32, and the upper surface 31 has a curved surface with a curvature R corresponding to the tips of the head cores 5a and 5b. Has become. The plurality of joints 32 are formed in a row in the direction in which the core bar 30 extends with the adjustment hole 39 interposed therebetween, and the direction of each joint 32 is in the direction in which the core bar 30 extends. . The joining portion 32 is a portion that becomes the gaps 22a and 22b of the head cores 5a and 5b shown in FIGS. The core bar 30 has a hole 33 and grooves 34 and 35 formed along the direction in which the core bar 30 extends. The holes 33 and the grooves 34 and 35 are portions to be the holes 23a and 23b and the grooves 24a, 24b, 25a and 25b for the coil winding shown in FIGS.
[0032]
The core bar 30 having such a configuration is created as follows. First, a C-shaped core bar 36 and an I-shaped core bar 37 are prepared. At this time, before bonding the bonding portion 32, a thin film serving as the gaps 22 a and 22 b is formed on the bonding portion 32 by sputtering, and the adjustment hole 39 is formed. The adjustment hole 39 adjusts the dimensions of the cores 5a and 5b to be created, and the length and the pitch of the joint 32 according to the size and pitch of the adjustment hole 39, that is, the core to be created. The track width Tw and the core width Cw of 5a and 5b are determined. Further, holes 33 and grooves 34 and 35 are formed in the C-type core bar 36 and the I-type core bar 37. Then, the C-shaped core bar 36 and the I-shaped core bar 37 are bonded together at the bonding portion 32 by glass bonding with a glass material 28, and then the upper surface 31 is polished to have a curved surface with a curvature R.
[0033]
Next, in the core cutting step, the two core bars 30 thus formed are cut out by a wire saw device (not shown) to form the head cores 5a and 5b. In this core cutting step, as shown in FIGS. 5A and 5B, first, the two core bars 30 (30a, 30b) are turned upside down to extend the core bar 30 (the direction of the joint 32). Is tilted by an azimuth angle of 6 ° with respect to the direction perpendicular to the cutting line L by the wire saw device, and a line Q connecting the end points P and P ′ of both joints 32 is parallel to the cutting line L. So that it is positioned on a wire saw device. This alignment is performed by moving one core bar 30 in the direction indicated by the arrow while keeping one core bar 30 in contact with the other core bar 30 while confirming the positions of points P and P ′ using a microscope or the like. Then, with the line Q connecting the points P and P 'being parallel to the cutting line L, the two core bars 30a and 30b are fixed to a jig for cutting with a wire saw device.
[0034]
When the two core bars 30a, 30b have been fixed to the jig, the core bars 30a, 30b are simultaneously cut out in the order of the cutout line L (LO, LA, LB, LC, LD). Each cutout line L passes through the position of the adjustment hole 39 and has a thickness d of the width of the wire. As a result, the two chips cut out from the two core bars 30a and 30b have the joining portions 32 as the gaps 22a and 22b and the head cores 5a and 5b.
[0035]
At this time, the chips cut out from the core bar 30a (portions A, B, C, and D in the drawing) are such that, when viewed from the direction of the upper surface 31, the joining portion 32 is inclined by + 6 ° with respect to a direction perpendicular to the cut surface. Become. On the other hand, the chips (A ', B', C ', and D' portions) cut out from the core bar 30b have -6 degrees with respect to the direction perpendicular to the cut surface when the joining portion 32 is viewed from the upper surface 31 direction. It becomes inclined. That is, the chips cut out from the core bar 30a are the head cores 5a for CH1 shown in FIGS. 2A, 2B, and 2C, and the chips cut out from the core bar 30b are shown in FIGS. 3A, 3B, and 3C. The head core 5b for CH2 shown in FIG.
[0036]
Chips (A and A ', B and B', C and C ', and D and D' parts) cut out simultaneously from the core bars 30a and 30b can be cut out even if an error occurs in the cutting position by the wire saw device. The height (corresponding to the gap reference height H1) from the surface to the points P and P ', which are the end points of the joint 32, is the same, and the thickness (corresponding to the core width Cw) is also the same. Therefore, the chips cut out at the same time constitute a pair of head cores 5a and 5b, and the rotary cylinder 3 is provided with magnetic heads 4a and 4b for CH1 and CH2 formed from the pair of head cores 5a and 5b. . As described above, in the core cutting step, two types of head cores 5a and 5b for H1 and CH2 having the same gap reference height H1 and core width Cw with the gaps 22a and 22b being opposite to each other are created.
[0037]
Next, in the head making step, the tip of the head core 5a thus created is polished to finish the tip of the head core 5a so as to have a curved surface in the thickness direction called a small radius. In this polishing, as shown in FIGS. 6A, 6B, and 6C, the head core 5a is sandwiched and held by a chucking jig 61, and a polishing tape 62 is pressed against the tip of the head core 5a. This is performed by sliding the slider 62 in the direction of the arrow shown in the figure. At this time, by strongly pressing the polishing tape 62, the polishing tape 62 is brought into a state of strongly hitting the edges 51 and 52 at the tip of the head core 5a due to the rigidity of the polishing tape 62. In this state, the polishing tape 62 is slid in the direction of the arrow in the drawing to advance the polishing, and as shown in FIG. 7, the head core 5a is finished so as to have a curved surface having a curvature r in the thickness direction. .
[0038]
When the tip of the head core 5a is polished, the coil winding 6a is applied to the head core 5a while the head core 5a is held by the chucking jig 61, as shown in FIGS. Thereby, the magnetic head 4a is created. Further, the magnetic head 4b is also manufactured from the head core 5b by the same process. In the above-mentioned polishing step and the step of applying the winding, the chucking jig 61 having the same shape as the conventional base is used, and the head core 5a is sandwiched and held up to the portion that has been bonded to the conventional base. The same polishing apparatus and winding apparatus as described above can be used.
[0039]
Then, in the head mounting step, the magnetic heads 4a and 4b thus produced are directly bonded at positions 180 ° opposite to each other with the cut surface of the head cores 5a and 5b sandwiching the rotating shaft of the rotary cylinder 3 therebetween. . Since the heights (gap reference height H1) from the cut surfaces of the head cores 5a and 5b to the gaps 22a and 22 are the same, the two magnetic heads 4a and 4b bonded to the rotary cylinder 3 rotate. The heights of the gaps 22a and 22b with respect to the bonding surface to the cylinder 3 are the same. In addition, what was conventionally adhere | attached on the core as a base is used.
[0040]
Finally, the lead wires 9a and 9b are soldered to the magnetic heads 4a and 4b and the printed circuit boards 10a and 10b, and the lead wires 11a and 11b are soldered to the printed circuit boards 10a and 10b and the rotary transformer 12, and the rotary cylinder 3 is mounted. The rotary magnetic head 1 is completed by being incorporated in the fixed cylinder 2.
[0041]
According to such a manufacturing method of the rotary magnetic head 1, two types of head cores 5 a, in which the gaps 22 a and 22 b are opposite in direction from the two identical core bars 30, and have the same gap reference height H 1 and the same core width Cw, 5b is created. By directly bonding the magnetic heads 4a and 4b formed from these two types of head cores 5a and 5b to the rotary cylinder 3, the heights of the gaps 22a and 22b of the two types of magnetic heads 4a and 4b become the same, This eliminates the need for the conventional base, mounting screw, height adjustment screw, and tapping of the rotating cylinder for tightening the screw. Further, since the two types of head cores 5a and 5b are formed from two identical core bars 30, that is, one type of core bar 30, the number of components and steps for forming the core bar 30 can be reduced.
[0042]
Note that the present invention is not limited to the configuration of the above embodiment, and various modifications are possible. For example, in the above-described embodiment, instead of two identical core bars, two types of core bars are formed in which the joints are formed in directions opposite to each other with respect to the direction in which the core bars extend, and these two types of core bars are formed. May be cut out at the same time in the same direction, with the corresponding positions of both gaps aligned. In this way, two types of head cores having the same gap reference height H1 and the same core width Cw can be produced with the gap directions reversed.
[0043]
Further, the present invention can also be applied to a rotating magnetic head in which a plurality of pairs of two types of magnetic heads called, for example, 4HD Hi-Fi Type are mounted at symmetrical positions around the rotation axis of the rotating cylinder. In this case, a plurality of pairs of core bars are prepared, and the plurality of pairs of core bars are cut out simultaneously by adjusting the corresponding positions of the respective gaps so that the gap directions are opposite, and the gap reference height H1 and the core width Cw are the same. A plurality of types of head cores may be created.
[0044]
【The invention's effect】
According to the first aspect of the present invention as described above,
(1) Since two identical core bars are turned upside down, the corresponding positions of the two gaps are obliquely aligned at a predetermined angle, and cut out in that direction in units of the thickness of the magnetic head core. Two types of magnetic head cores having the same height up to the gap can be produced.
(2) The two types of magnetic heads formed by applying coil windings to these two types of magnetic head cores are directly bonded to the rotating cylinder, so that a conventional head mounting base, mounting screws, and height adjusting screws are unnecessary. In addition, tapping of the rotary cylinder for tightening the screw is not required, and a more inexpensive product can be obtained.
(3) Since two types of magnetic head cores are formed by cutting two identical core bars upside down and obliquely cutting them, the number of components and the number of steps for core bar creation are reduced, and the cost is further reduced. Products.
[0045]
According to the invention of claim 2,
(1) Two types of magnetic head cores in which the direction of the gap is opposite and the height to the gap is the same, since two core bars are taken as one pair and one or a plurality of pairs are cut out while aligning the corresponding positions of the respective gaps. Can be created.
(2) One or more pairs of two types of magnetic heads formed by applying coil windings to these magnetic head cores are directly bonded to the rotating cylinder, so that the same effects as above can be obtained.
[0046]
According to the third aspect of the present invention, the two types of magnetic head cores forming a pair are formed by cutting two identical core bars upside down and cut diagonally, so that the number of parts for forming the core bars and the number of parts are reduced. The number of processes is small, and a more inexpensive product can be obtained.
[0047]
According to the fourth aspect of the present invention, a head mounting base and a height adjusting screw are not required, and an inexpensive rotary magnetic head can be obtained.
[Brief description of the drawings]
FIG. 1 is a sectional view showing a schematic configuration of a rotary magnetic head according to an embodiment of the present invention.
2A is a front view showing a configuration of a head core for CH1 of the rotary magnetic head, FIG. 2B is a plan view thereof, and FIG.
3A is a front view showing a configuration of a head core for CH2 of the rotary magnetic head, FIG. 3B is a plan view of the same, and FIG.
FIG. 4 is a perspective view showing a configuration of a core bar for cutting out and creating a head core of the rotary magnetic head.
FIG. 5A is a perspective view showing a method of cutting a head core from the core bar, and FIG. 5B is a view seen from above.
6A is a plan view showing a method of polishing a head core, FIG. 6B is a side view thereof, and FIG. 6C is a partial enlarged view of the same side.
FIG. 7 is a partially enlarged side view showing a state after polishing of the head core.
8A is a plan view showing a method of applying a coil winding to the head core, and FIG. 8B is a side view of the same.
FIG. 9 is a sectional view showing a schematic configuration of a conventional rotary magnetic head.
FIG. 10A is a view of the rotary cylinder showing the state of attachment of the conventional magnetic head to the rotary cylinder, viewed from below, and FIG.
11A and 11B are partially enlarged front views showing the configuration of a conventional magnetic head.
12A is a plan view showing a configuration of a conventional head core, FIG. 12B is a front view thereof, and FIG. 12C is a partial enlarged view of the front thereof.
FIG. 13 is a side view showing a conventional method of attaching a head core to a base.
14A is a plan view showing the shape of the tip of a conventional head core, FIG. 14B is a side view thereof, and FIG. 14C is a partial enlarged view of the same side.
FIG. 15 is a plan view showing a conventional method of applying a coil winding to a head core.
FIG. 16A is a plan view showing soldering of a conventional magnetic head to a printed circuit board, and FIG. 16B is a side view of the same.
[Explanation of symbols]
1 rotating magnetic head
2 Fixed cylinder
3 rotating cylinder
4a, 4b magnetic head
5a, 5b head core
6a, 6b coil winding
22a, 22b gap
30 core bar
61 Chucking Jig

Claims (4)

Two types of magnetic heads are formed by applying coil windings to two types of magnetic head cores formed by inclining a gap for generating a magnetic flux at a predetermined angle in a direction opposite to each other, and forming these two types of magnetic heads on a magnetic tape. A method for manufacturing a rotating magnetic head, which is mounted at a position 180 ° opposite to an outer peripheral surface of a rotating cylinder serving as a running surface with a rotating shaft interposed therebetween,
A core bar creating step of creating at least two identical core bars in which a portion serving as the magnetic head core is connected in a row in a direction along the portion serving as the gap;
The two core bars created in the core bar creation step are turned upside down, and the corresponding positions of both gaps are aligned and fixed obliquely at the predetermined angle, and these two core bars are fixed at the predetermined angle. A core cutting step of cutting out the two types of magnetic head cores by cutting one magnetic head core in a diagonal direction in thickness units;
Holding the magnetic head core cut out in the core cutting step by a jig, polishing the tip of the magnetic head core, and applying a coil winding to the magnetic head core to form the two types of magnetic heads; and ,
A head mounting step of directly bonding the two types of magnetic heads formed in the head forming step to the rotary cylinder by bonding. Two types of magnetic heads are formed by applying coil windings to two types of magnetic head cores in which gaps for generating magnetic flux are inclined at a predetermined angle in directions opposite to each other to form one pair or plural pairs of the two types of magnetic heads. In a method for manufacturing a rotating magnetic head, one or more pairs of magnetic heads are mounted at symmetrical positions around a rotation axis on an outer peripheral surface of a rotating cylinder serving as a running surface of a magnetic tape,
A core bar creating step of creating a pair of at least two core bars in which a plurality of portions serving as the magnetic head cores are connected in a row;
The two core bars prepared in the core bar forming step are taken as one pair, and one or more pairs of the core bars are aligned and fixed at the corresponding positions of the gaps, and these one or more pairs of core bars are connected to one magnetic head core. Core cutting step of cutting out the two types of magnetic head cores in pairs or plural pairs by cutting out in units of thickness;
A method for manufacturing a rotating magnetic head, comprising: a head mounting step of directly mounting one or more pairs of magnetic heads formed from the magnetic head cores cut in the core cutting step to the rotating cylinder. The core bar creating step is to create at least two identical core bars in which a portion serving as the magnetic head core is connected in a row in a direction along the portion serving as the gap,
In the core cutting step, the two core bars created in the core bar creating step are turned upside down, the corresponding positions of both gaps are aligned and fixed, and these two core bars are inclined at the predetermined angle. 3. The method of manufacturing a rotating magnetic head according to claim 2, wherein the two types of magnetic head cores are cut out in a direction in a thickness unit of one magnetic head core. A rotary magnetic head manufactured by the method for manufacturing a rotary magnetic head according to claim 1.

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