GB2238157A

GB2238157A - Loading/unloading mechanism for read and/or write head

Info

Publication number: GB2238157A
Application number: GB9021791A
Authority: GB
Inventors: Takamitsu Sugahara; Junji Kawada
Original assignee: Mitsubishi Electric Corp
Current assignee: Mitsubishi Electric Corp
Priority date: 1989-10-06
Filing date: 1990-10-08
Publication date: 1991-05-22
Anticipated expiration: 2010-10-08
Also published as: GB9021791D0; JP2706329B2; DE4031618A1; JPH03122878A; GB2238157B; DE4031618C2

Abstract

A mechanism for loading/unloading a read and/or write head (1a, 1b) of a disk drive apparatus against a magnetic disk (3), includes a lifter (6a, 6b) which bends a suspension (2a, 2b) supporting the read and/or write head. The suspension is bent by moving the lifter in response to movement of the head actuator (4) to detach the read and/or write head mounted on a tip of the suspension (2a, 2b) from the magnetic disk (3) by a given distance, to protect the heads (1a, 1b) and the disk (3) from damage. <IMAGE>

Description

1 LOADING/UNLOADING MECHANISM FOR READ AND/OR WRITE HEAD The present

invention relates to a loading/unloading mechanism for read and/or write head used in a disk drive apparatus which drives a disk recording medium, and in particular to simplification of its structure.

In the accompanying drawings, Fig. 1 is a plan view showing an example of a loading/unloading mechanism of a conventional disk drive apparatus published in "NIKKEI ELECTRONICS", 1986., 3-24, No. 391, pp 90 to pp 99, and Fig. 2 is a perspective view showing its structure. In the figures, numeral 1 indicates a sliding-type read and/or write head which reads and/or writes a magnetic disk 3. The read and/or write head 1 is installed on a tip of a tapered suspension 2 and supported thereon so as to the magnetic disk 3.

to be urged in a direction contacting In the midway of the suspension 2, a cam 21 engaged with a lifter 6 to be described later is provided. The base end of the suspension 2 is mounted on an actuator 4 which swings about a pivot shaft 41. Actuator 4 is formed into a shape of sickle and in the midway thereof, a strut 71 which serves as a rotating center of a link arm 7 supporting the lifter 6 is projected. The link arm 7 is provided with the bar lifter 6 on its one end, and on the other end, a cam pin 72 engaged with a latching can 24 to be described later is protruded. The link arm 7 is urged counterclockwise by means of a spring 27, and the lifter 6 is regulated its counterclockwise movement by a stopper pin 23 contacting to its base end. The stopper pin 23 is movable up 2 and down by a loading solenoid 22. The latching cam 24 is for retaining the lifter 6 in the vicinity of the root of the suspension 2, and provided with a latch groove 24a engaged with the cam pin 72 on its periphery. The latching cam 24 swings about a pivot 24b and is usually urged counterclockwise by a latching spring 25. Thereby, the latching groove 24a and the cam pin 72 are kept in contact when they are engaged with each other. The latching cam 24 is rotated clockwise by a cam releasing solenoid 26 to release engagement between the latch groove 24a and the cam pin 72.

Next, the loading and unloading operation of the conventional loading/unloading mechanism of the read and/or write head constituted in such a way will be described.

Referring to Fig. 1, first, the case where the read and/or write head I moves from the unloading state in which it is detached from the magnetic disk 3, to the loading state in which it contacts to the magnetic disk 3 is described.

The actuator 4 is rotated about the pivot shaft 41 to bring the head 1 to the outermost periphery of the medium 3. Next, the solenoid 22 is energized to project the stopper pin 23. Then, while a portion of the link arm 7 to which the lifter 6 is fixed is caught by the pin 23, the actuator 4 is rotated reversely in an inner circumferential direction. At this time, since the strut 71 of the link arm 7 is f ixed to the actuator 4, the link arm 7 is rotated in the opposite direction of the rotation of the actuator arm 4 or clockwise in Fig. 1, and the lifter 6 is moved in the releasing direction of the cam 21 disposed on the suspension 2, thereby the head 1 is 3 contacted to the magnetic disk 3 to achieve the loading state. While, the cam pin 72 fixed to a portion of the link arm 7 and having the pivoting strut on the actuator 4, is moved to the position where it is caught by the latch groove 24a provided on the cam 24 pre-loaded by the cam spring 25. Furthermore, the solenoid 22 is released and the pin 23 is retracted to complete the loading operation.

Next, the unloading operation for detaching the head 1 from the magnetic disk 3 is described. When the current preserved in a capacitor and the like, not shown, is applied to the cam releasing solenoid 26 installed on the actuator 4 when a power source of the disk drive apparatus is cut off, a portion of the cam 24 is attracted and cam 24 is rotated clockwise, thereby the cam pin 72 caught by the latch groove 24a is released. As a result, the link arm 7 is rotated in the direction in which the lifter 6 approaches to the head 1 by the unloading spring 27, or counterclockwise in Fig. 1 and the head 1 is detached from the magnetic disk 3 to complete the unloading operation.

Fig. 3 of the accompanying drawings is a perspective view showing a configuration of a conventional disk drive apparatus of a contact start and stop system (CSS), in which the read and/or write head is not loaded nor unloaded. In the figure, numeral 31 designates a spindle motor which rotates the magnetic disk 3, and in the CSS system, keeps the read and/or write head 1 standstill on a shipping zone provided on the innermost periphery of the magnetic disk 3 at a time of nonoperation. The read and/or write head 1 is installed on a tip i.

4 of the suspension 2. The base end of the suspension 2 is mounted on a tip of the actuator 4. The actuator 4 swings about the pivot shaft 41.

When starting the disk drive apparatus of the CSS system, the spindle motor 31 is rotated while keeping the read and/or write head 1 standing still on the magnetic disk 3. In general, the head 1 is kept standstill at the inner circumference side on the magnetic disk 3. Though the head I rubs the magnetic disk 3 in the beginning, when a given revolution is achieved,,.it starts to float above the magnetic disk 3 by the air bearing effect. At normal revolution of the spindle motor, it floats at a constant height of about 0.2gin. When the disk drive apparatus is stopped and the revolution of the spindle motor reduces to a certain constant revolution from the normal revolution, the head 1 begins to contact with the magnetic disk 3 and keeps rubbing the magnetic disk 3 until the spindle motor stops. Accordingly, it has been devised to stop the spindle motor positively for shortening the sliding distance.

Since the conventional head loading and unloading mechanism is constituted as aforementioned, the number of component parts increases, and it is necessary to insure a wide region for component parts and a region in which the lifter moves to unload the read and/or write head. Also, sequential operations for operating the component parts in constant order are necessitated, resulting in uncertainty of operation and frequent troubles. Moreover, there are such problems as complicated assembling and a high cost.

1 i Meanwhile in the conventional CSS system, the lower the floating height of the read and/or write head from the magnetic disk, the less the frequency of contact start and stop, resulting in a shorter life. The higher the recording density the lower must be the floating height, resulting in the longer rubbing distance between the head and the magnetic disk and causing the problems. Also, as the head contacts directly to the medium the vibration and shock resistance at the time of non-operation was limited. Besides, when the number of magnetic disks as the magnetic disk increases and contact resistance of the read and/or write head therewith becomes larger, the starting torque of the spindle motor must be increased that much. In this system, at the starting of the spindle motor, since the motor is not reversible, angular position detecting means of certain accuracy must be provided in a spindle motor driving circuit. Furthermore, it is also necessary to provide means for reducing the idling time of the spindle motor at the time of interruption of the power source.

The present invention has been devised in view of such circumstances. It is therefore, an object of the present invention to provide a loading/unloading mechanism for read and/or write head in which component parts can be reduced.

It is an object of an embodiment of the present invention to provide a loading/unloading mechanism for read and/or write head, in which the read and/or write head can be detached by a given distance from a magnetic disk in a narrow region, and in which the read and/or write head can be retracted outside a periphery of a disk as the magnetic disk.

6 According to the present invention there is provided a loading and unloading mechanism for read and/or write head constructed such that, a lifter is moved up and down to lift a suspension of the read and/or write head, and to detach the read and/or write head from the magnetic disk. Furthermore, the suspension of the read and/or write head is moved on the lifter to the outside of the magnetic disk. Moreover, the lifter is moved by a portion of an actuator arm which moves and positions the read and/or write head.

The. lifter of the read and/or write head in the invention, when the actuator arm which moves and positions the read and/or write head is moved outside beyond the outermost periphery of the magnetic disk, lifts the suspension of the head to detach the head from the magnetic disk by being moved up and down. Moreover, while detaching the head from the magnetic disk, the suspension is slid on the lifter to move and retract the head, and to be retained, to the outside of the region of the magnetic disk.

Embodiments of the present invention will now be described by way of example with reference to the accompanying drawings, in which:

Fig. 1 is a plan view showing a conventional head loading and unloading mechanism; Fig. 2 is a perspective view of the mechanism shown in Fig. 1; Fig. 3 is a perspective view showing a conventional contact start and stop system; Fig. 4 is a plan view showing a head loading and un- 7 loading mechanism according to one embodiment of the present invention; Fig. 5 and Fig. 6 are sectional views taking along the line 5.5 of Fig. 4, and Fig. 7 is a sectional view of a head loading and unloading mechanism showing another embodiment of the present invention.

In Figs. 4 and 5, numeral la, lb designate slidingtype read and/or write heads which read and write both sides of a magnetic disk 3, the read and/orwrite heads la, lb being installed on tips of tapered suspensions 2a, 2b and supported thereon so as to be urged in the directions contacting to the magnetic disk 3. The base end of the suspension 2a, 2b are mounted on an actuator 4 which swings about a pivot shaft 41, and by the swinging motion of the actuator 4, the read and/or write heads la, lb swing in the substantially radial direction of the magnetic disk 3. To the actuator 4 a link 5 having a shell-shaped section with grooves 51a, 51b on the upper and lower surfaces on its tip is joined together and moves integrally with the actuator 4. Between the suspension 2 and the magnetic disk 3, bar lifters 6a, 6b extending longitudinally generally in the radial direction of the magnetic disk 3 are interposed. Tips of the lifters 6a, 6b are located slightly inside from the peripheral edge of the magnetic disk 3, and their base ends are mounted on link arms 7a, 7b. The link arms 7a, 7b are in the shape of flat bar and extending longitudinally in the circumferential direction of the magnetic disk 3. The link arms 7a, 7b are facing each 8 other and provided with protrusions extending in the radial direction in the midway to receive the base ends of the lifters 6a, 6b. The link arms 7a, 7b clamp a strut 10 at one of their ends and swing about the strut 10. The other ends of the link arms 7a, 7b have tapered portions 74a, 74b therebetween, into which the arm 5 penetrates. When the arm 5 penetrates into the tapered portions 74a, 74b, the link arms 7a, 7b swing repectively in different rotating directions. By this swinging notion, the lifters 6a, 6b lift the suspension 2 to detach the read and/or write heads la, lb from the magnetic disk 3. The link arms 7a, 7b are urged respectively in the different rotating directions by means of springs 8a, 8b wound around the strut 10. The strut 10 is fixed to one end of the support 9 in an axial direction which is substantially parallel to a recording surface of the magnetic disk 3. On the other end of the support 9, a stopper 11 for regulating the swinging motion of the arm 5 is disposed., Next, the operation of the loading/unloading mechanism of this embodiment of the invention will be described.

First, the unloading operation is described. As shown in Fig. 5 and Fig. 6, as the actuator 4 is driven clockwise and the read and/or write heads la, lb approach the peripheral edge of the magnetic disk 3, the arm 5 whose end is a shellshaped cam structure penetrates between the tapered portions 74a, 74b of the tapered link arms 7a, 7b, and the link arms 7a, 7b are rotated about the strut installed on the support 9 of the link arm, whereby the lifters 6a, 6b are moved up and down i 9 and the suspensions 2a, 2b are lifted. As a result, the read and/or write heads la, lb are detached from the magnetic disk 3 by a given distance, and further, the arm 5 abuts against the stopper 11, thereby the link arms 7a, 7b engage with the grooves 51a, 51b provided on the tip of the arm 5 and are latched. At this time, the heads la, lb move in the state of being detached from the magnetic disk 3 and are retracted further to the outside of the peripheral edge of the magnetic disk 3. This operation is effected at the time of the standstill of the disk: drive apparatus and at the time of an emergency when some troubles have occurred.

Next, the loading operation will be described. When the actuator 4 is driven counter-clockwise from the unloading state as aforementioned, the latching state between the link arms 7a, 7b and the arm 5 is released, and the heads la, lb are brought to the loading state by the operation which is completely opposite from the unloading operation.

In the aforesaid embodiment, although a case in which a swinging type actuator 4 to move and position the read and/or write head 1 is used has been described, a linear driving typeactuator may also be used.

Also, in the embodiment aforementioned, although a case in which the bar lifter 6 is used has been described, a plate lifter may also be used.

Moreover, in the embodiment mentioned above, although a case in which one magnetic disk and two read and/or write heads are used has been described, one or more magnetic disks and two or more heads, as shown in Fig. 7, may also be used for the same effect as the aforesaid embodiment. In this case, when connecting the link arms 7c, 7d, 7e and 7f with the gear mechanism 73c, 73d, 73e and 73f and moving, for example, only a portion 73f of the gear mechanism by the actuator 4, the other link arms 7c, 7d and 7e may be designed to interlock with each other. Here, in Fig. 7, 1c, id, le and If are read and/or write heads, 2c, 2d, 2e and 2f are suspensions, 3a, 3b are magnetic disk and 6c, 6d, 6e and 6f are lifters.

Moreover, the read and/or write head may be a read head or a write head.

As stated above, since the read and/or write head is so constructed as to detach from the magnetic disk, the life of a storing apparatus is prolonged and high reliability can be obtained.

Also, the head is moved to and retained at the outside of the peripheral edge of the medium, so that it may be detached only a little and a high shock resistance can be obtained.

Also, by retracting immediately an emergency arises, recording data on the medium is not spoiled.

In addition, since the damping distance at the time of runaway is not influenced by the allowance of the medium, it can be longer and deceleration can be reduced.

As this invention may be embodied in several forms without departing from the essential characteristics thereof, the present embodiment is therefore illustrative and not restrictive, since the scope of the invention is defined by the appended claims rather than by the description preceding them,

1 11 and all changes that fall within the meets and bounds of the claims, or equivalence of such meets and bounds thereof are therefore intended to be embraced by the claims.

12

Claims

CLAIMS:

1. A loading/unloading mechanism for a read and/or write head which is supported by a suspension and moves above/on a magnetic disk, the mechanism comprising, a lifter for interposing between said magnetic disk and said suspension, engaged with said suspension and movable toward and away from said magnetic disk; and driving means for moving said lifter responsive to movement of said read and/or write-head.

2. A loading/unloading mechanism as set forth in claim 1, wherein said lifter is mounted on a link arm provided to swing around an axis substantially parallel to a recording surface of said magnetic disk, and moves with the swinging notion of said link arm.

3. A loading/unloading mechanism as set forth in Claim 1 or 2, wherein said driving means, when said read and/or write head approaches the peripheral edge of said magnetic disk, moves said lifter away from said magnetic disk, and moves said read and/or write head away from said magnetic disk at a predetermined distance.

4. A loading/unloading mechanism as set forth in any preceding Claim, wherein said driving means includes means for biasing said link arm in one direction and means for rotating said link arm in the other direction responsive to movement of 1 r 1 13 said read and/or write head.

5. A loading/unloading mechanism for a read and/or write head substantially as herein described with reference to Figures 4 to 6 and/or Figure 7 of the accompanying drawings.

1 1 Published 1991 at The Patent Office, State House. 66/71 High Holborn, londonWCIR4TIl- Further copies maybe obtained from Sales Branch. Unit 6, Nine Mile Point. Cwmfelinfach. Cross Keys. Newport NPI 7HZ. Printed by Multiplex techniques ltd. St Mary Cray, Kent.