JPH0368465B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a double-sided magnetic disk device that converts signals using both sides of a magnetic disk cartridge, generally called a floppy disk. The present invention relates to an improvement in a support mechanism for a pair of magnetic heads.

[Conventional technology and its problems]

An apparatus for performing data conversion using both sides of a flexible magnetic disk is disclosed, for example, in US Pat. No. 4,089,029. In the device disclosed herein, a pair of magnetic heads (transducers) are each gimballed and supported by a pair of symmetrical carriages with the disk at the center, so that the magnetic head can easily follow the deflection of the disk. Not only is it better, but the wear on the disk is also less. However, since both magnetic heads are supported by gimbals and the magnetic heads are attached to the tips of arm-shaped leaf springs, off-track tends to occur when the rotational plane of the disk deviates from the reference plane. Furthermore, since the pair of carriages that support the pair of magnetic heads have a swing arm configuration and open to both sides when no disk is loaded, the thickness of the head support mechanism inevitably increases, resulting in a thinner magnetic disk device. It becomes difficult to

On the other hand, in order to prevent track deviation, the lower magnetic head is fixed to a carriage that can move only in the radial direction of the disk, and the upper magnetic head is attached to the swing arm using a gimbal spring seat, as disclosed in US Pat. No. 4,151,573. Disclosed. With this configuration, track deviation will certainly be reduced. However, because the magnetic head must be attached to the swing arm via a gap spring, the head support mechanism becomes complicated and expensive. In addition, since the lower magnetic head is fixed, even if the height position of the disk rotation plane changes due to an error in the height position of the disk rotation device or a dimensional error of the disk cartridge, the lower magnetic head It is impossible for the head to follow the disk. For this reason, the disk must be deformed and pressed against the lower fixed head, and the head load pressure must necessarily be designed to be large. This results in increased disk wear. Some devices are designed so that the lower magnetic head moves vertically, but they are not designed so that the pressing forces of the pair of magnetic heads against the disk are equal. For this reason, it is not possible to obtain good followability of the magnetic head to the disk.

The above-mentioned problem occurs conspicuously on the inner circumferential side of the 3.5-inch floppy disk device disclosed in Japanese Patent Application Laid-Open No. 117464/1983. That is, on the inner circumference side of the small disk, the rigidity of the disk during rotation is large, and the disk will not deform unless a considerably large pressing force is applied. Since it is practically difficult to vary the pressing force depending on the location of the disk, a large pressing force is always applied, which results in increased wear.

Furthermore, in a conventional double-sided disk device in which a magnetic head is attached to a carriage that moves only in the radial direction, at least the upper magnetic head is supported by a gimbal. As a result, the magnetic head vibrates due to the stick-slip phenomenon, which tends to deteriorate conversion characteristics and cause track deviation.

SUMMARY OF THE INVENTION It is therefore an object of the present invention to provide a double-sided magnetic disk device with less track deviation and less disk wear.

[Means for solving problems]

A magnetic head device according to the present invention for solving the above problems and achieving the above object includes a disk rotation device for rotating a flexible recording medium magnetic head, and a disk rotation device for rotating a flexible recording medium magnetic head; first and second magnetic heads arranged opposite each other so as to contact a surface and perform magnetic conversion of signals; a carriage that holds the first magnetic head and moves only in the radial direction of the disk; means for guiding said carriage in a disk radial direction; and said first
is provided between the magnetic head of the disk and the carriage, and in a state where the first and second magnetic heads are kept in non-contact with the disk, the first magnetic head is provided between the reference rotation plane of one surface of the disk. The first magnetic head is supported such that a gap surface of the magnetic head protrudes, and the first magnetic head is displaceable only in a direction substantially perpendicular to the plane of the disk. A magnetic head is supported, and when the first and second magnetic heads are in contact with the disk, the magnetic head is configured to apply a force in the direction of the second magnetic head to the first magnetic head. an elastic support device,
The second magnetic head is mounted in a non-gimbal supported state and is supported by the carriage so as to move integrally with the carriage in the radial direction of the disk, and the second magnetic head is connected to the first magnetic head. a head support that is movable relative to the carriage so as to be able to move away from the head; and the second magnetic head applies a force to the head support in a direction toward the first magnetic head. When the first and second magnetic heads are in contact with the disk, the first magnetic head applies a force substantially equal to the force with which it presses the disk in the direction of the second magnetic head. an elastic displacement device configured to apply pressure so that the second magnetic head presses the disk; and a head support configured to separate the second magnetic head from the disk when a signal is not converted. and a spacing device for displacing the body.

[Effect]

In the magnetic disk device of the above invention, since both the first and second magnetic heads are non-gimbally supported, the occurrence of the stick slip phenomenon is prevented.
Deterioration of conversion characteristics and track deviation are less likely to occur. Furthermore, even with non-gimbal support, the first and second magnetic heads can be displaced in the direction perpendicular to the disk plane, and the pressing forces of the first and second magnetic heads against the disk are approximately equal. ,
The error in the height position of the rotation mechanism when the disk rotation plane
Even if there is a change due to disc error or the like, the first and second magnetic heads are displaced to follow the change, and signal conversion can be continued. Furthermore, since there is no need to fix the disk to the magnetic head, there is no need to increase the force with which the second magnetic head is pressed toward the disk. This reduces disk wear.

〔Example〕

Next, a floppy disk device according to an embodiment of the present invention shown in FIGS. 1 to 4 will be explained.

The magnetic disk cartridge 1 used in this embodiment has a relatively rigid case (not shown).
A flexible magnetic disk 2 is rotatably housed in the disk, and is the same as that disclosed in, for example, Japanese Patent Application Laid-open No. 117464/1983. Therefore,
A metal hub 3 is provided at the center of the disk 2. The disk rotating device 4 is also the same as that disclosed in the above publication, and a rotary table 6 is coupled to a motor 5, a magnet 7 for attracting the hub 3 is provided on the rotary table 6, and a magnet 7 is attached to the hub 3. A spindle 8 and a drive pin (not shown) for matching are provided. Therefore, in this example, there is a height difference between the rotation plane of the disk 2 and the upper surface 6a of the rotary table 6.

The first magnetic head 9, which is brought into contact with the lower surface of the disk 2, is attached in a non-gimbal supported state to a highly rigid carriage 11 made of synthetic resin via an elastic support device 10. This carriage 11 is movable in the radial direction of the disk 2 guided by a guide rod 39 as a guide means, and is driven by a radial drive mechanism 13, which is shown in principle in the block.

The first magnetic head 9 has a cylindrical head support 14 that is movable only in a direction perpendicular to the surface of the disk 2.
It is fixed to the upper surface part 15 of. The support body 14 has a cylindrical part 16 having a square cross section, which is movably inserted into a square part provided in the carriage 11. The flange 18 of the support 14 corresponds to the step 19 of the hole 17.
This is the part that engages with. This stepped portion 19 and collar portion 18
The upper limit of the support 14 and the first magnetic head 9 is determined by the engagement with the support 14 and the first magnetic head 9. A coil spring 21 is disposed between the bottom plate 20 that closes the lower part of the hole 17 and the upper surface portion 15 of the support body 14. This coil spring 2
1 applies an upward biasing force to the first magnetic head 9 via the support 14 during signal conversion. The gap surface 9a, that is, the top surface of the first magnetic head 9 projects beyond the disk reference rotation plane 22 shown by the chain line when the head is not loaded as shown in FIG. Therefore, the pressing force of the first magnetic head 9 can be obtained during head loading as shown in FIG.

The second magnetic head 23 is for signal conversion in contact with the other surface of the disk 2, and is fixedly attached to a highly rigid synthetic resin swing arm 25 via a shield/mounting plate 24. . Since this second magnetic head 23 is non-gimbaled, the mounting plate 24 does not have complicated cutouts like conventional gimbaled support sheets.

Since the swinging arm 25 is attached to the carriage 11 by a leaf spring 26 having a spring hinge function, it moves in the disk radial direction simultaneously with the carriage 11 and carries the upper magnetic head 23.
This swing arm 25 can therefore be referred to as an upper carriage or head support. 27 is a torsion spring, one end of which biases the swinging arm 25 in the counterclockwise direction in FIG.
5 is pressed. Note that the coil portion of this torsion spring 27 is wound around the shaft 29 of a support piece 28 fixed on the carriage 11. Leaf spring 2
6 is the swing arm 25 when the torsion spring 27 is removed.
Most of the pressing force of the second magnetic head 23 against the disk 2 is applied by the torsion spring 27. The pressing force of this torsion spring 27 is set to be approximately equal to the pressing force of the first magnetic head 9 against the disk 2. The gap 23a of the second magnetic head 23 fixed to the mounting plate 24 in a non-gimbaled manner is in surface contact with the upper surface of the disk 2, and faces the gap surface 9a of the first magnetic head 9. , 23 are not opposed to each other to prevent mutual interference. The magnetic heads 9, 23 are shown schematically, but have a core and a winding, and the core is held between ceramic sliders and the disk 2.
The upper surface that comes into contact with is finished to be a smooth surface. Further, the illustration of lead wires led out from the magnetic heads 9 and 23 is also omitted.

Reference numeral 30 denotes an engaging portion provided for controlling head load and non-load, and projects from the swing arm 25. As shown in FIG. 3, a separation control piece 31 is engaged here, and when the head is not loaded, the swinging arm 25 is rotated clockwise against the torsion spring 27, and the second magnetic head 23 is rotated clockwise. disk 2
Separate from.

When recording or reproducing data with this device, the cartridge 1 is loaded with the swinging arm 25 rotated clockwise as shown in FIG. At this time, the cartridge 1 is inserted slightly above the first magnetic head 9 and the rotary table 6, as shown by the chain line in FIG. 1, and then lowered onto the rotary table 6. Turntable 6 that allows disk 2 to rotate
When the separation control piece 31 is lowered from the position shown in FIG. 3 to release the restriction on the swing arm 25, the force of the torsion spring 27 causes the swing arm
5 is rotated to the head load position shown in FIG. The gap surface 9a of the first magnetic head 9 protrudes beyond the disk reference rotation plane 22 when the head is not loaded, but since it is pressed through the disk 2 by the second magnetic head 23, the gap surface 9a of the first magnetic head 9 is The flange 18 is pushed down in the vertical direction so that the flange 18 is released, and the flange 18 is separated from the step 19 as shown in FIG. As a result, the coil spring 21 is compressed and deformed, producing a biasing force that pushes the first magnetic head 9 upward. If the disk 2 is rotating in alignment with the reference rotation plane 22, the first and second magnetic heads 9, 2
3 presses the disk 2 from opposite directions with the same pressing force.

By the way, the disk 2 does not always coincide with the reference rotation plane 22. The position of the disk 2 with respect to the first magnetic head 9 changes minutely due to changes in the height T due to manufacturing errors in the hub 3, errors in the height of the turntable 6, displacements of the disk 2 during rotation, etc. . However, in this device, the first magnetic head 9 is vertically movable and has a pressing force against the disk 2, and this pressing force is set equal to the pressing force of the second magnetic head 23. Therefore, depending on the height change of disk 2,
The first and second magnetic heads 9, 23 follow.
Therefore, good signal conversion characteristics can be maintained.

In the conventional device, the lower first magnetic head 9 was fixed or the pressing forces of the first and second magnetic heads 9, 23 were not set equal, so that the height of the disk 2 did not change. Instead of making the magnetic heads 9, 23 follow the disk 2, the disk 2 is deformed so that the magnetic heads 9, 23 follow the disk 2.
followed. For this reason, the force of the torsion spring 27 must be designed to be large and the pressing force of the second magnetic head 23 against the disk 2 must be increased, which inevitably increases wear on the disk 2. The present device can overcome the drawbacks of the conventional devices mentioned above.
Note that when the magnetic heads 9 and 23 are in contact with the inner peripheral side of the disk 2 near the hub 3, the rigidity of the disk 2 increases, making it difficult for the disk 2 to deform.
In the conventional device, a large pressing force is set in order to obtain an appropriate head contact state even in this state, and as a result,
The wear on disk 2 has increased.

In this device, a pair of magnetic heads 9 and 23 are supported in a non-gimbal manner. Therefore, vibrations due to the stick-slip phenomenon are less likely to occur, and good high-density recording or reproduction with less track deviation is possible.
Further, the pair of magnetic heads 9, 23 is a U.S. patent
Since the device is not supported by a leaf spring arm like the device disclosed in No. 4089029, there is less track deviation.

[Modified example]

The present invention is not limited to the above-described embodiments, and, for example, the following modifications are possible.

(A) Instead of constructing an elastic support device by combining the coil spring 21 and the support body 14, as shown in FIG. Leaf spring 3
The pressure may be obtained by the spring action of step 2. Also, the first
A leaf spring may be inserted in place of the coil spring 21 shown in the figure, and the support body 14 may be pressed by this.

(B) Instead of the torsion spring 27, a compression coil spring may be used to press the swing arm 25. Further, a biasing force for head load may be applied to the leaf spring 26.

(C) The mounting plate 24 may be constructed of a leaf spring so that the pressing force of the second magnetic head 23 can also be obtained from this.

(D) Instead of the swing arm 25, a member that moves parallel to the carriage 11 may be provided.

(E) Of course, it is also applicable to a disk device using the disk cartridge disclosed in US Pat. No. 4,089,029.

〔Effect of the invention〕

As is clear from the above, according to the present invention, it is possible to reduce disk wear and track deviation. Therefore, high-density recording or reproduction becomes possible.

[Brief explanation of drawings]

1 is a partially cutaway front view of a magnetic disk device according to an embodiment of the present invention, FIG. 2 is a front view showing a state in which a magnetic head is in contact with a disk, and FIG. 3 is a front view of the magnetic head of FIG. 1. FIG. 4 is a perspective view of the first magnetic head of FIG. 1 and its vicinity, and FIG. 5 is a plan view of a modified plate spring. 2... Disk, 9... First magnetic head, 9a...
Gap surface, 10... Elastic support device, 11... Carriage, 14... Head support, 21... Coil spring,
22...Reference rotating surface, 23...Second magnetic head, 2
3a... Gap surface, 25... Swing arm, 27... Torsion spring.

Claims (1)

[Scope of Claims] 1. A disk rotating device for rotating a flexible recording medium magnetic disk; and a disk rotating device arranged to face each other so as to contact one and the other surface of the disk to perform magnetic conversion of signals. first and second magnetic heads; a carriage that supports the first magnetic head and moves only in the radial direction of the disk; means for guiding the carriage in the radial direction of the disk; and the first magnetic head. and the carriage, and in a state where the first and second magnetic heads are kept in non-contact with the disk, the first magnetic head is arranged from a reference rotation plane on one surface of the disk. the first magnetic head is supported such that a gap surface of the disk protrudes, and the first magnetic head is supported such that the first magnetic head can be displaced only in a direction substantially perpendicular to the plane of the disk. an elastic member configured to support the first magnetic head and apply a force in the direction of the second magnetic head to the first magnetic head when the first and second magnetic heads are in contact with the disk; a support device, the second magnetic head being mounted in a non-gimbaled support state and supported by the carriage so as to move integrally with the carriage in the radial direction of the disk; a head support that is movable relative to the carriage so as to be able to move away from the first magnetic head; the first and second magnetic heads are in contact with the disk;
an elastic displacement device configured such that the second magnetic head presses the disk with a pressing force substantially equal to the force with which the magnetic head presses the disk in the direction of the second magnetic head; . A separating device for displacing the head support so as to separate the second magnetic head from the disk when signals are not converted. 2. The magnetic disk device according to claim 1, wherein the head support is an arm that supports the second magnetic head near one end thereof and is swingably attached to the carriage.