JPH06168427A - Magnetic disk device - Google Patents

Abstract

PURPOSE:To increase a recording capacity by making a switching access to both upper and lower disk planes with a both-side floating head, thereby making a magnetic disk thinner while reducing a distance between opposed planes of the magnetic disk medium and increasing the number of the medium to be laminated. CONSTITUTION:An access switching means 5 is formed on both upper and lower sides of a movable supporting beam 2 by sticking a pair of piezoelectric elements 51 with an adhesive. Then, a voltage is so impressed to the upper side element 51a that the beam 2 is shrunk in a longitudinal direction and to the lower side element 51a and the beam 2 is enlongated in the same direction. Thus, the beam 2 is made to displace like a spring to an A direction. Besides, when an inverse voltage is impressed to them, the beam 2 is made to displace like a spring in a B direction. In this constitution, a both-side floating head is loaded by negative pressure since the beam 2 is displaced in either of directions like a spring by the means 5. The floated-up plane of the head loaded once on the disk surface is kept in the loaded state by the negative pressure caused by the rotation of the magnetic disk medium.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a magnetic disk device, and more particularly to a floating head access switching structure for recording / reproducing.

In recent years, magnetic disk devices are required to be thin and have large capacity, and it is important to mount a number of magnetic disk media as recording media in one inch, and the distance between the facing surfaces of the magnetic disk media is narrowed. It is desired to reduce the thickness and make the recording capacity large.

[0003]

2. Description of the Related Art In a conventional magnetic disk drive, as shown in the plan view of FIG. 5, a plurality of magnetic disk media 11a are stacked and fixed on a single axis at predetermined intervals and rotated by a rotation driving means (not shown). Magnetic disk structure 11
And the upper and lower floating (or contact type) heads 12a-1 and 12b-1 are separately mounted between the upper and lower disk surfaces facing each other, and the lower flexible support beams 12a and 12b are installed inside the device. The rotary head positioner 14 is provided with a double-headed magnetic head 12 attached to the tip of a support arm 13 (which rotates about a support shaft 13a in the radial direction of the magnetic disk medium 11a).

In addition, the upper and lower flexible support beams 12a and 12b need to be as thin as possible because it is necessary to narrow the space between the disk surfaces, and the upper and lower floating heads 12a-1 and 12b-1 do not overlap but the mounting height thereof. Are attached to the support arm 13 so as to have a thickness of one floating head so as to be offset from each other in plan view.

[0005]

However, according to the mounting structure of the single-sided floating head in the above-mentioned magnetic disk device, the supporting arm becomes large in size for mounting the upper and lower flexible supporting beams, so that the inertial force is increased. There is a problem that the moment becomes large, and because the two upper and lower floating heads are two-dimensionally offset from each other, the zones to be accessed are different, and there are zones that cannot be accessed, and the recording density becomes worse especially in the case of a small-diameter magnetic disk medium. was there.

In view of the above problems, it is an object of the present invention to provide a magnetic disk device capable of reducing the distance between the facing surfaces of the magnetic disk medium to reduce the thickness and increase the recording capacity.

[0007]

To achieve the above object, in a magnetic disk device of the present invention, a double-sided head having an electromagnetic conversion element for recording / reproducing and an air bearing surface or a disk contact surface on both upper and lower surfaces. The double-sided head is opposed to a support arm for connecting a flexible support beam attached to the tip of the double-sided head, a magnetic disk structure in which a plurality of magnetic disk mediums are stacked on a single axis at a distance slightly larger than the thickness of the double-sided head. Access disc switching means for spring displacement of the flexible support beam so as to selectively access either one of the disk surfaces.

[0008]

By providing the access switching means with respect to the flexible support beam having the double-sided head attached at the tip, the access switching means actuates the flexible support beam and spring-displaces the flexible support beam. By making the head follow one of the facing surfaces of the adjacent magnetic disk media by negative pressure, one of the surfaces can be selectively accessed, so that the distance between the facing surfaces of the magnetic disk medium is 1 It is possible to reduce the thickness of each head, eliminate the inaccessible zone, and reduce the thickness to increase the recording capacity.

[0009]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT A preferred embodiment shown in the drawings will be described in detail below. 1A and 1B are a plan view and a side view of a main part of a magnetic disk device.

As shown in the figure, a support arm 3 for connecting a flexible support beam 2 having a double-sided floating head 2a having an electromagnetic transducer 2a-1 for recording / reproducing and an air bearing surface on both upper and lower surfaces and attached at the tip. And a magnetic disk assembly 1 in which a plurality of magnetic disk media 1a (two magnetic disk media facing each other are shown) are uniaxially separated and stacked at a distance D slightly larger than the thickness T of the double-sided floating head 2a. The double-sided floating head 2a is composed of the access switching means 5 which spring-displaces the flexible support beam 2 so as to selectively access either one of the facing surfaces of the adjacent magnetic disk medium 1a.

The electromagnetic conversion element 2a-1 is a thin film element and is provided on the side surface of the double-sided floating head 2a (slider block) corresponding to the upper disk surface. Further, the support arm 3 is
The rotary type positioner 4 provided in the apparatus rotates the magnetic disk medium 1a substantially in the radial direction as in the conventional case.

The access switching means 5 is composed of a pair of piezoelectric elements (piezo elements) 51a fixed to the upper and lower surfaces of the flexible support beam 2 with an adhesive (not shown) as shown in FIG. A flexible voltage is applied to the element 51a so that the flexible support beam 2 contracts in the longitudinal direction, and a voltage is applied to the piezoelectric element 51a on the lower surface side so that the flexible support beam 2 extends in the longitudinal direction. The support beam 2 is bent to one side (direction of arrow A) and spring-displaced. On the contrary, by applying a voltage, the spring is displaced to the other side (direction of arrow B).

With this construction, the flexible support beam is spring-displaced to either side by the access switching means, so that the double-sided floating head is loaded by the negative pressure. The air bearing surface of the double-sided floating head once loaded on the disk surface can be kept in the loaded state by the negative pressure generated by the rotation of the magnetic disk medium.

It should be noted that the double-sided floating head maintains neutrality during unloading, or when stopped, the head is brought into contact with one of the disk surfaces to float as the rotational speed increases.
(Contact Start Stop) method may be used. In this case as well, the access switching means may switch to the other surface. Alternatively, only one piezoelectric element may be fixed to either the upper or lower surface of the flexible support beam, and a voltage for expanding or contracting the piezoelectric element may be applied and loaded. Further, a thermoelectric deformation element can be used instead of the piezoelectric element.

2 (a) and 2 (b) are a plan view and a side view of a main part of another embodiment (second embodiment) of the access switching means. The access switching means 5 of this embodiment, that is, 52
Is provided on both ends of the stroke of the flexible support beam 2, that is, on the frame structure 6 corresponding to the outermost peripheral position and the innermost peripheral position, a switching block 52a having a pair of opposite slopes 52a-1. When switching the access surface,
The flexible support beam 2 is moved forward (or backward) with a full stroke, and the left side edge (right side edge) of the flexible support beam 2 abuts the slope 52a-1 of the switching block 52a and is guided as it is. As in the embodiment, the flexible support beam 2 is configured to be bent and spring-displaced.

With this structure, the second embodiment operates in the same manner as the first embodiment, and the upper and lower disk surfaces can be switched and accessed by one double-sided floating head.

Next, FIG. 3 is a plan view and a side view of a main part of still another embodiment (third embodiment) of the access switching means. The access switching means 5, that is, 53 of this embodiment is
A pair of switching levers 53a facing each other are rotatably pivoted on the frame structure 6 corresponding to both ends of the stroke of the flexible support beam 2, that is, the outermost position and the innermost position. One of the switching levers 53a has an operating lever portion 53a-1 and a reversing lever portion 53a-2 integrally formed in an L shape, and is pivotally attached by a pivot shaft 53c serving as a rotation fulcrum provided at a corner portion. Further, a tension spring 53d is attached to the reversing lever portion 53a-2 side,
By urging the stopper 53e so as to come into contact with the stopper 53e, the holding position is always maintained.

The other switching lever 53a has the same structure and is arranged opposite to the opposite side. Then, when the access surface is switched, the flexible support beam 2 is moved forward (or backward) with a full stroke so that the left side edge (right side edge) of the flexible support beam 2 of one switching lever 53a. Actuating lever part 53a-1
At the same time that the flexible supporting beam 2 is pushed down around the pivot 53c by pushing it, the tip of the reversing lever portion 53a-2 pushes the lower surface (upper surface) of the flexible supporting beam to move the flexible supporting beam 2 in the same manner as in the previous embodiment. It is configured to bend and displace the spring.

With this structure, the third embodiment operates in the same manner as the first and second embodiments, and
Two double-sided floating heads can be used to access either the upper or lower disk surface.

In the access switching means described with reference to FIG. 3, a tension spring is used to return after the switching operation and maintain the standby posture. However, as another access switching means 54, a plan view of a main part of FIG. Also, as shown in the side view, even if the L-shaped switching lever 54a is supported by a leaf spring 54b in a cantilever manner, the same action and effect are obtained. Further, as the head structure, a contact type head is also possible in addition to the floating type head as in each embodiment.

[0021]

As described above in detail, according to the present invention,
Since the upper and lower disk surfaces can be switched and accessed by one double-sided floating head, the distance between the facing surfaces of the magnetic disk medium is further narrowed to reduce the thickness, and the number of laminated magnetic disk media is increased to increase the recording capacity. It has an extremely useful effect in industry, such as a large capacity.

[Brief description of drawings]

FIG. 1 is a plan view and a side view of a main part of a magnetic disk device according to an embodiment of the present invention.

FIG. 2 is a plan view and a side view of a main part of another embodiment of the access switching means of FIG.

3 is a plan view and a side view of a main part of still another embodiment of the access switching means of FIG.

FIG. 4 is a plan view and a side view of a main part of another embodiment of the access switching means of FIG.

FIG. 5 is a plan view showing a schematic configuration of a conventional magnetic disk device.

[Explanation of symbols]

1 is a magnetic disk structure 52a is a switching block 1a is a magnetic disk medium 52a-1 is a slope 2 is a flexible support beam 53a is a switching lever 2a is a double-sided head (double-sided floating head) 53a-1 is an operating lever 2a-1 The electromagnetic conversion element 53a-2 is the reversing lever portion 3, the support arm 53d is the tension spring 5,51,52,53 is the access switching means 53e, the stopper 51a is the piezoelectric element 6, and the frame structure is

Claims (4)

[Claims] 1. A flexible supporting beam (2) having a double-sided head (2a) having an electromagnetic conversion element (2a-1) for recording / reproducing and an air bearing surface or a disk contact surface on both upper and lower surfaces and attached at the tip. Support arm (3) that connects the
(a) is selected on either one of the disk surface (1) on which the double-sided head (2a) faces and the magnetic disk structure (1) in which the double-sided head (2a) is separated and laminated at a distance slightly larger than the thickness of the double-sided head (2a). Flexible support beam for selective access
A magnetic disk device comprising: an access switching means (5) for displacing (2) by a spring. 2. The access switching means (51) according to claim 1.
Is a pair of piezoelectric elements on the upper and lower surfaces of the flexible support beam (2).
(51a) is fixed, one is extended and the other is contracted, or only one piezoelectric element (51
A magnetic disk drive characterized in that the flexible supporting beam (2) is spring-displaced by applying a voltage for fixing and stretching or contracting a). 3. The access switching means (52) according to claim 1.
Is provided with a switching block (52a) having a pair of opposite slopes (52a-1) on the frame structure (6) corresponding to both extreme positions of the stroke of the flexible support beam (2), Due to the forward movement of the flexible support beam (2), the side edges are
A magnetic disk drive characterized in that the flexible support beam (2) is spring-displaced by being guided by collision with (2a-1). 4. The access switching means (53) according to claim 1.
On the frame structure (6) corresponding to both extreme ends of the stroke of the flexible support beam (2) and the operating lever part (53a-1) and the reversing lever part (53a-2) facing each other. A switching lever (53a) integrally formed into an L-shape is pivotally mounted so as to be rotatable, and the reversing lever portion (53a-2) is further pulled by a spring.
(53d) contacts the stopper (53e) and keeps it in the standby position at all times, and the reversing lever is pushed by pushing the actuating lever part (53a-1) around by the forward movement of the flexible support beam (2). A magnetic disk drive characterized in that the tip of the portion (53a-2) pushes the upper surface (or the lower surface) of the flexible support beam (2) to spring-displace the flexible support beam (2). .