Abstract:
A system and method for an improved magnetic head arm assembly (HAA), reducing complexity of design and difficulty of manufacture, is disclosed.

Description:
RELATED APPLICATIONS 
   This application is a Divisional of patent application Ser. No. 10/640,357, filed on Aug. 13, 2003 now U.S Pat. No. 7,142,394 which claims the benefit of priority to PCT/CN03/00104, filed on 30 Jan. 2003. 

   BACKGROUND INFORMATION 
   The present invention relates to magnetic hard disk drives. More specifically, the present invention relates to a system for an improved magnetic head arm assembly (HAA). 
   Among the better known data storage devices are magnetic disk drives of the type in which a magnetic head slider assembly floats on an air bearing at the surface of a rotating magnetic disk. Such disk drives are often called ‘Winchester’-type drives. In these, one or more rigid magnetic disks are located within a sealed chamber together with one or more magnetic head slider assemblies. The slider assemblies may be positioned at one or both sides of the magnetic disks. 
   Typically, each magnetic head slider assembly in magnetic disk drives of the type referred to is coupled to the outer end of an arm or load beam.  FIG. 1  provides a perspective view of a typical magnetic head arm (HAA) assembly  108 . The slider  102  is mounted in a manner which permits gimbaled movement at the free outer end of the suspension  106  such that an air bearing between the slider assembly  102  and the surface of the magnetic disk can be established and maintained. The elongated suspension  106  is coupled to an appropriate mechanism, such as a voice-coil motor (VCM) (not shown), for moving the suspension  106  across the surface of the disk (not shown) so that a magnetic head contained within the slider  102  can address specific concentric data tracks on the disk for writing information on to or reading information from the data tracks. 
   In order to achieve a quick response ability, a focus has been placed on reducing the weight (and thus, the inertial effects) of the HAA  108 . A typical means of achieving this has been to reduce the thickness  110  of the HAA  108 . To prevent HAA  108  operational flexure (and thus, poor tracking) and/or unintentional deformation during the assembly processes, rib elements  112  are utilized (such as in U.S. Pat. No. 5,313,353 of Kohso et al.). The rib elements  112  reduce the tendency of the HAA  108  to flex towards and away from the disk surface. 
   Problems with this design  108  include the complexity of design and difficulty of manufacture. Many complex cutting and bending processes must be performed to produce this HAA baseplate  108 . This greatly affects quality control as well as cost of production. It is therefore desirable to have a system and method for an improved magnetic head arm assembly (HAA) that avoids the above-mentioned problems, in addition to other advantages. 

   
     BRIEF DESCRIPTION OF THE DRAWINGS 
       FIG. 1  provides a perspective view of a typical magnetic head arm assembly (HAA). 
       FIG. 2  illustrates Head Arm Assembly (HAA) design and assembly according to an embodiment of the present invention. 
       FIG. 3  provides a cross-section view of the coupling between the unimount suspension arm and the flexure/load beam assembly under principles of the present invention. 
   

   DETAILED DESCRIPTION 
     FIG. 2  illustrates Head Arm Assembly (HAA) design and assembly according to an embodiment of the present invention. In this embodiment, an HAA structure  206  includes a flexure/load beam assembly  202  and a unimount suspension arm  204 . The suspension arm  204  is formed from a uniform piece of material. In one embodiment the suspension arm is made from a material that has a high Young&#39;s Modulus(Y)-to-density(D) ratio, such as Aluminum with Y/D=110 Mpsi/(lb/in 3 ) (Y=11 Mpsi (megapounds per square inch) and D=0.10 lb/in 3  (pounds per cubic inch)) or Titanium with Y/D=106 Mpsi/(lb/in 3 ) (Y=17 Mpsi and D=0.16 lb/in 3 ). In an embodiment, the suspension arm  204  is of a material having a Y/D of at least 100 Mpsi/(lb/in 3 ). 
   In one embodiment of the present invention, the suspension arm  204  has a thickness  214  of at least 0.7 millimeters (mm), and in one embodiment, the thickness of the suspension arm  204  is 0.8 mm. Further, in an embodiment, the thickness is at least 2.5% the length  211  of the HAA  206  (axis of rotation to magnetic head). For example, a 2.5 inch hard disk drive (HDD), having a 28.5 mm length HAA  206 , in one embodiment of the invention has a suspension arm thickness  214  of at least 0.7 mm (2.5% the length). 
   In one embodiment, the unimount suspension arm  204  is coupled to the flexure/load beam assembly  202  to form the HAA  206 . In an embodiment, the coupling is performed by laser welding overlapping portions  208  of the two components  202 ,  204 . In an alternative embodiment, thermosetting epoxy is utilized to couple the two components  202 ,  204 . In an embodiment, alignment holes  210  are utilized to accurately position the components  202 ,  204  upon one another. 
     FIG. 3  provides a cross-section view of the coupling between the unimount suspension arm  302  and the flexure/load beam assembly  304  under principles of the present invention. As stated above, in one embodiment laser welding  306  is utilized to join the two components  302 ,  304 . In one embodiment, spot welds are performed at several locations  306  (see also  FIG. 2 ). 
   Although several embodiments are specifically illustrated and described herein, it will be appreciated that modifications and variations of the present invention are covered by the above teachings and within the purview of the appended claims without departing from the spirit and intended scope of the invention.