Abstract:
A system and method for improving the design and manufacturing process of a hard disk drive magnetic head arm assembly (HAA) by welding specific components is disclosed.

Description:
BACKGROUND INFORMATION  
         [0001]    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).  
           [0002]    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 magnetic disk drive may include one or more rigid magnetic disks, and the slider assemblies may be positioned at one or both sides of the magnetic disks.  
           [0003]    [0003]FIG. 1 provides an illustration of a typical hard drive as used in the art. The slider assembly  104  may be mounted in a manner which permits gimbaled movement at the free outer end of the arm  102  such that an air bearing between the slider assembly  104  and the surface of the magnetic disk  106  can be established and maintained. The drive arm  102  is coupled to an appropriate mechanism, such as a voice-coil motor (VCM)  108 , for moving the arm  102  across the surface of the disk  106  so that a magnetic head contained within the slider assembly  104  can address specific concentric data tracks on the disk  106  for writing information on to or reading information from the data tracks.  
           [0004]    Because of the decreasing scale of hard drive components and the demand for increased hard drive capacity, the minimization of manufacturing tolerances and consistency of assembly have become a large priority. The coupling of certain hard drive components by materials such as adhesives causes difficulty with regards to manufacturing complexity and quality control. Common adhesives utilized in hard drive assembly include anisotropic conductive film (ACF), anisotropic conductive adhesive (ACA), and epoxy. These adhesives have disadvantages such as being susceptible to changes in temperature and humidity. For example, as viscosity changes under heat, parts can shift from their desired position. Also, the softness of the adhesive makes it difficult to work with (e.g., positioning, cutting an accurate size piece, etc.). Further, adhesives are susceptible to particle and chemical (ion) contamination. Still further, adhesives typically provide poor electrical conduction properties necessary to discharge electrostatic build-up. It is therefore desirable to have a system and method for improving the manufacture of hard disk drive arm assemblies that avoids the above-mentioned problems, in addition to other advantages.  
       
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0005]    [0005]FIG. 1 provides an illustration of a typical hard drive as used in the art.  
         [0006]    [0006]FIG. 2 illustrates two methods of welding hard drive components according to an embodiment of the present invention.  
         [0007]    [0007]FIG. 3 illustrates two additional methods of welding hard drive components according to an embodiment of the present invention.  
         [0008]    [0008]FIG. 4 provides an illustration of a head suspension with an attached slider according to an embodiment of the present invention.  
         [0009]    [0009]FIG. 5 provides an illustration of a head suspension with a micro-actuated slider according to an embodiment of the present invention.  
         [0010]    [0010]FIG. 6 provides an illustration of the attachment of head suspension to hard drive arm according to an embodiment of the present invention.  
         [0011]    [0011]FIG. 7 provides an illustration of the attachment of hard drive flex cable to hard drive arm according to an embodiment of the present invention.  
         [0012]    [0012]FIG. 8 provides an illustration of the attachment of hard drive flex cable to hard drive arm according to a different embodiment of the present invention.  
         [0013]    [0013]FIG. 9 provides an illustration of the attachment of hard drive bridge flex circuit (BFC) to head suspension according to an embodiment of the present invention.  
     
    
     DETAILED DESCRIPTION  
       [0014]    To avoid the above-mentioned problems associated with the usage of materials such as adhesives in hard drive assembly, components are joined by different methods of welding under principles of the present invention.  
         [0015]    [0015]FIG. 2 illustrates two methods of welding hard drive components according to an embodiment of the present invention. Ultrasonic welding, illustrated in FIG. 2 a , utilizes ultrasonic waves  201  to heat the components. In one embodiment, a first hard drive component  202  is fused  203  directly to a second hard drive component  204  by the heat. In this embodiment, the first and second components are metal such as copper or gold. Solder bump bond (SBB) welding, illustrated in FIG. 2 b , utilizes a heat source such as ultrasonic waves  207  to heat the components. In an embodiment, the first hard drive component  206  is heated to a point at which a solder ‘bump’ (ball)  210 , attached to the second component  208 , is melted, joining the first and second components upon cooling. In an alternative embodiment, the first hard drive component is heated to a point at which a solder ‘bump’ (ball), attached to the first component, is melted, joining the first and second components upon cooling (configuration not shown).  
         [0016]    [0016]FIG. 3 illustrates two more methods of welding hard drive components according to an embodiment of the present invention. Laser welding, illustrated in FIG. 3 a , utilizes a laser beam  301  to heat the components. In one embodiment, a first hard drive component  302  is fused  303  directly to a second hard drive component  304  by the heat. In this embodiment, the first and second components are metal such as copper, gold, or stainless steel. ‘Pin and hole’ welding, illustrated in FIG. 3 b , utilizes a welding pin that is inserted into a hole in each component. In an embodiment, the second hard drive component  306  has a cylindrical recession  308  in which a welding pin  310  is inserted. In this embodiment, the diameter of the recession  308 , as compared to the diameter of the pin  310 , is such that the pin  310  is coupled to the second component  306  by an interference fit (friction). In an alternative embodiment, the pin and hole each have a rectangular cross-section. In an embodiment, the first hard drive component  312  is coupled to the pin  310  by a solder bond of a material such as Tin, which is applied by a tool such as a soldering iron  316 . In another embodiment, the second hard drive component and pin are formed as one piece during manufacture (not shown).  
         [0017]    [0017]FIG. 4 provides an illustration of a head suspension with an attached slider according to an embodiment of the present invention. In one embodiment, the slider  402  is attached to the slider frame  404  of the head suspension (head gimbal assembly(HGA))  406  by welds  410  between two welding pads  408  on the slider  402  and two tabs on the slider frame  404 . In one embodiment, these welds are performed by ultrasonic welding. In another embodiment, the welds are performed by SBB welding. In a further embodiment, the welds are performed by laser welding.  
         [0018]    [0018]FIG. 5 provides an illustration of a head suspension with d micro-actuated slider according to an embodiment of the present invention. Similar to above, in one embodiment, the slider  502  is attached to the slider frame  504  of the head suspension  506  by welds  510  between two welding pads  508  on the slider  502  and the slider frame  504 . Note that the slider frame  502  illustrated is for micro-actuation of the slider (whereas the slider frame  402  in FIG. 4 is not). Two piezoelectric arms  507  are utilized to minutely adjust the slider&#39;s position with respect to the head suspension  506  and hard drive arm (not shown). As above, in one embodiment, the welds are performed by ultrasonic welding; in another embodiment, the performed by SBB welding; and in a further embodiment, the welds are performed by laser welding.  
         [0019]    In one embodiment of the present invention, the slider frame  504  is attached to suspension  506  via welding  512 . As above, in one embodiment, the welds are performed by ultrasonic welding; in another embodiment, the welds are performed by SBB welding; and in a further embodiment, the welds are performed by laser welding.  
         [0020]    [0020]FIG. 6 provides an illustration of the attachment of head suspension to hard driver arm according to an embodiment of the present invention. In a preferred embodiment, the welds between head suspension  602  and hard drive arm  604  are performed by pin and hole welding  606 . In another embodiment, the welds are performed by ultrasonic welding; in another embodiment, the welds are performed by SBB welding; and in a further embodiment, the welds are performed by laser welding.  
         [0021]    [0021]FIG. 7 provides an illustration of the attachment of hard drive flex cable to hard drive arm according to an embodiment of the present invention. In one embodiment, the welds between flex cable  702  and hard drive arm  704  are performed by pin and hole welding.  
         [0022]    [0022]FIG. 8 provides an illustration of the attachment of hard drive flex cable to hard drive arm according to a different embodiment of the present invention. In one embodiment, the welds between flex cable and hard drive arm are performed by ultrasonic welding  802 ; in another embodiment, the welds are performed by SBB welding  804 ; and in a further embodiment, the welds are performed by laser welding  806 .  
         [0023]    [0023]FIG. 9 provides an illustration of the attachment of bard drive bridge flex circuit (BFC) to head suspension according to an embodiment of the present invention. In one embodiment, the welds between BFC  902  and head suspension  904  are performed by ultrasonic welding; in another embodiment, the, welds are performed by SBB welding; and in a further embodiment, the welds are performed by laser welding.  
         [0024]    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.