1. Field of the Invention
The present invention relates to a recording disk drive such as a hard disk drive unit (HDD), and in particular, to a recording disk drive comprising a recording disk, a suspension cantilevered on a carriage arm to tilt in the forward direction toward a disk surface of the recording disk, and a head supported at the free end of the suspension.
2. Description of the Prior Art
A flying head has been generally known capable of writing and reading information data to and from a recording disk or magnetic disk without contacting the disk surface of the recording disk, for example, in the field of hard disk drive units (HDDs). The lift of the flying head is usually generated by air stream flowing along the disk surface during rotation of the magnetic disk. When the rotation is terminated, the flying head cannot keep flying above the disk surface. No air stream leads to the result that the flying head is urged against the disk surface under the effect of elastic restoration of the suspension. The flying head must be prevented from contacting the data tracks or area on the disk surface when the rotation of the magnetic disk has been terminated.
A contact start stop (CSS) is well known in which the flying head is urged against the non-data tracks or an area at the innermost portion of the disk surface. The CSS allows the flying head to take off from the disk surface if enough air stream has been generated on the disk surface after the magnetic disk starts to rotate. However, in this CSS, the flying head must be released from adhesion from a lubricating oil or agent spread over the disk surface when the head takes off from the disk surface. As the size of a flying head gets smaller, it becomes nearly impossible for the flying head to easily take off from the disk surface once the flying head is urged against the disk surface.
On the other hand, a ramp load proposes a utilization of the warp of the suspension supported at the tip end of the carriage arm in avoiding the contact between the flying head and the stationary disk surface. The warp may be caused by a support member disposed outside the magnetic disk. As long as the warp of the suspension is kept, the flying head at the free end of the suspension can be kept away from the disk surface. If the flying head is positioned above the data tracks or area on the disk surface with the warp kept in the suspension, the flying head cannot contact the disk surface. No adhesion from a lubricating oil or agent acts on the flying head.
The support member of the ramp load is adapted to form a ramp in the path of the suspension. When the suspension climbs up the ramp in response to the swinging movement of the carriage arm, the warp gets larger in the suspension. The larger warp makes a higher position of the flying head above the disk surface. On the other hand, the ramp causes a twist in the suspension, too. If such twist remains in the suspension, the degree of the warp is changed in the suspension. This change may lead to deterioration in controllability of attitude and/or position of the flying head when information data is read out of or written in the magnetic disk.
It is accordingly an object of the present invention to provide a suspension load mechanism contributing to prevention of a twist in a suspension supporting a head.
According to a first aspect of the present invention, there is provided a recording disk drive comprising: a recording disk; a suspension cantilevered on a carriage arm to tilt in a forward direction toward a disk surface of the recording disk; a head supported at a free end of the suspension; and a lift bar moveable along a path intersecting the suspension.
With the above-described recording disk drive, the warp in the suspension gets larger as the lift bar contacting the suspension advances in the path intersecting the suspension. As long as the warp is maintained in the suspension, the head at the free end of the suspension can be kept away from the disk surface of the recording disk. If the head is always shifted to positions above the data area with the warp kept in the suspension, the head can be prevented from contacting the disk surface. No adhesion acts on the head from a lubricating oil or agent spread over the disk surface.
The recording disk drive preferably further comprises a support member supporting the lift bar in parallel with the disk surface. If the lift bar is kept in parallel with the disk surface, it is possible to prevent the suspension from twisting by adjusting the orientation of the path of the lift bar to the tilting direction of the suspension.
The recording disk drive may further comprise a drive mechanism which generates a drive force acting on the support member to move the lift bar. In particular, the drive mechanism preferably comprises a cam formed on the carriage arm so as to cause the drive force in response to swinging movement of the carriage arm. Such advancement of the lift bar in response to the swinging movement of the carriage arm enables to eliminate a drive source to be added to the recording disk drive for driving the lift bar. However, the drive mechanism may be adapted to move the lift bar with assistance of any additional drive source without utilization to the swinging movement of the carriage arm.
The adjustment in orientation of the tilting direction of the suspension to the path of the lift bar may require an orientation adjuster causing a directional force to change an orientation of the lift bar in a plane parallel to the disk surface in response to the swinging movement of the carriage arm. For example, when the tilting direction is complied with the central line of the suspension, the suspension keeps the constant distance from the disk surface along the direction perpendicular to the central line. Accordingly, as long as the lift bar in parallel with the disk surface contacts the suspension at the line perpendicular to the central line, the constant distance from the disk surface can be maintained along the direction perpendicular to the central line in the suspension. The suspension can then be prevented from twisting.
The orientation adjuster may comprise: a first guide passage extending in a first direction along the path of the lift bar; a pivot moveable along the first guide passage so as to support the support member; a second guide passage extending in a second direction intersecting the first direction; and a guide member formed on the support member so as to move along the second guide passage in response to movement of the pivot, thereby causing swinging movement of the support member around the pivot. Such orientation adjuster enables the lift bar to follow the change in the orientation of the suspension in accordance with the swinging movement of the carriage arm.
In addition, the recording disk drive may further comprise an insertion mechanism generating a force to move the lift bar between a standby position defined outside the recording disk and an operating position defined between the suspension and the recording disk. Such insertion mechanism serves to keep the lift bar away from the recording disk while the head is operated to write or read information data. It is accordingly possible to reliably prevent the lift bar from interfering with the head, the suspension, the carriage arm, and the like.
The insertion mechanism may comprise: a support member supporting the lift bar at its tip end; a pivot supporting the support member for swinging movement; and a cam formed on the carriage arm so as to cause the swinging movement of the support member in response to swinging movement of the carriage arm. Such insertion mechanism enables the lift bar to shift between the standby and operating positions with assistance of swinging movement of the carriage arm. Such shift of the lift bar in response to the swinging movement of the carriage arm possibly eliminates a drive source to be added to the recording disk drive for driving the lift bar. However, the insertion mechanism may be adapted to move the lift bar with assistance of any additional drive source without utilization to the swinging movement of the carriage arm.
In case where the swinging movement of the carriage arm is utilized to move the lift bar between the standby and operating positions, the cam according to the insertion mechanism may also generate a drive force to cause advancement of the support member. A single drive source common to the insertion and drive mechanisms may lead to a simplified structure in the recording disk drive.
The recording disk drive may simultaneously comprise the insertion mechanism and the above-described orientation adjuster. In this case, the pivot in the insertion mechanism may be guided in the first guide passage of the orientation adjuster.