Abstract:
An invertible tray for components on a strip is disclosed. A stack of trays can be manipulated to invert the orientation of its contents with minimum disturbance to the component strips. In addition, the tray includes adjustable rails for accommodating component strips of various dimensions.

Description:
FIELD OF THE INVENTION  
       [0001]     The present invention relates to an adjustable tray for handling a plurality of hard disk drive heads in two different orientations. The invention is designed for handling partial or complete HDD heads, hereinafter referred to as suspension assemblies.  
       BACKGROUND OF THE INVENTION  
       [0002]     An HDD suspension assembly is a fragile part that comprises a triangular-shaped portion, a base, a suspension arm and at least one magnetic read/write head. A flexible circuit is attached to the forward portion of the assembly. HDD suspensions are generally fabricated in groups of five or ten suspensions per strip, and then singulated before shipping. During the fabrication process it is necessary to access the suspensions on the top and bottom side of each tray. Currently, HDD suspensions must be manually removed from the tray for inspection, inverted and then placed back into the tray during processing. Suspensions that are manually inverted are susceptible to damage. Merely inverting a tray can introduce substantial contaminants into a stack of trays if the tray contents are dropped down into a receiving tray of a stack. Therefore, a need exists for an invertible tray that does not introduce contaminants due to vertical movement of the contents when the tray is manipulated.  
       SUMMARY OF THE INVENTION  
       [0003]     The present invention concerns an apparatus for handling a strip having components thereon (herein component strip or simply strip). The apparatus includes a first tray having a first side with protrusions adapted to retain a component strip in a first orientation. In addition, the apparatus includes a second tray having a second side which has protrusions adapted to retain a component strip in a second orientation. The first side of the first tray is adapted to engage the second side of the second tray such that, when the trays are inverted, the strip is transferred from the first tray to the second tray and becomes supported in a new orientation by protrusions on the second tray.  
         [0004]     In another embodiment the invention is directed to a stack of trays having a top surface and a bottom surface, each surface being useable for handling a plurality of suspension assemblies. Each tray in the stack has alignment bars, a locating rail and a retention rail. The suspension assemblies are held in a first orientation by at least one protrusion extending from the locating rail on one of the trays. The suspension assemblies are inverted by manipulating the stack so that the openings on the plurality of suspension assemblies rest on at least one protrusion extending from a second tray. The suspension assemblies are captured by the retention rails and the protrusions between the two trays. As a result, the suspension assemblies are accessible for inspection from either the top or bottom surface of the stack. In yet another embodiment, the invention is directed to a tray that is both invertible and adjustable. 
     
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0005]      FIG. 1  illustrates a suspension assembly on a strip.  
         [0006]      FIG. 2  is a perspective view of the invertible tray of the present invention.  
         [0007]      FIG. 3  is a partial side view of a stack of trays in accordance with the present invention.  
         [0008]      FIG. 4A  is a top isometric view of the present invention.  
         [0009]      FIG. 4B  is a partial view of a stack of trays in accordance with the present invention.  
         [0010]      FIG. 4C  is a bottom isometric view of the tray shown in  FIG. 4A .  
         [0011]      FIG. 5  is an enlarged isometric view of a suspension assembly captured between two trays. 
     
    
     DETAILED DESCRIPTION OF THE INVENTION  
       [0012]     The present invention is designed to facilitate the handling of components that are on a strip. Specifically, the tray can handle strips during different processing stages. The invention will be described in reference to HDD suspensions attached to a strip. However, the invention can apply to any other type of articles that are progressively built on a strip of material, with additional elements being added to the strip in each successive manufacturing stage.  
         [0013]      FIG. 1  illustrates the general features of a suspension strip  100 . The HDD suspension strip has five suspension assemblies, each having a triangular-shaped portion  10 , a base, a suspension arm  15  and at least one magnetic read/write head  18 . Along an outer edge  150  of the suspension strip are a series of openings  55 .  FIG. 1  illustrates a flexible circuit  125  that is attached to the periphery of each HDD assembly  60  on strip  100 . It is understood that a partially-completed HDD suspension assembly might omit certain elements that are present in  FIG. 1 . The trays of the present invention are suitable for handling partial HDD suspension assemblies, as well as complete HDD suspension assemblies.  
         [0014]     In reference to  FIGS. 2 and 3 , a tray for handling a plurality of suspension assemblies is shown. Tray  20  has a top profile  30  and a bottom profile  40 . The top profile  30  is configured to hold a plurality of suspension assemblies in one orientation. The bottom profile  40  is configured to handle a component strip in an orientation reverse from the top profile.  
         [0015]     As shown in  FIG. 2 , each primary surface of tray  20  has protrusions  22  and retention rails  35  for holding component strip  100  (not shown) in place. Protrusions  22  are located on opposing surfaces of locating rail  25  at periodic intervals. Although the protrusions  22  are shown as having a conical shape, they can instead have contours that are hemispherical, rectangular, hexagonal, or any other type of shape. Locating rail  25  may have various configurations including a linear, serpentine, sinusoidal or other configuration. Locating rail  25  also contains apertures  24  that interlock with protrusions  22  on a locating rail from an abutting tray. The apertures  24  are contoured to match the shape of the protrusions  22 .  
         [0016]     Tray  20  can handle component strip of various dimensions by adjusting locating rail  25  and retention rails  35  along alignment bars  32 ,  34  and alignment bars  42 ,  44 . In order to properly capture components between abutting trays, it is preferable that each locating rail and retention rail in a first tray have a similar position as in a second tray that abuts the first tray. Retention rails  35  and protrusions  22  support the component strip in a desired position in the tray stack.  
         [0017]      FIG. 3  illustrates a partial side view of a stack composed of two trays. Only trays carrying suspensions of the same dimensions will properly nest together. In particular, protrusions  22  from one side of a first tray  270  interlock with apertures  24  on a second tray  280  when their respective locating rails  25  are in similar positions. Conversely, protrusions  22  from the second tray interlock with apertures  24  on the first tray when locating rails  25  are spaced a similar distance from the side wall  230  of each tray.  
         [0018]     Each tray may optionally include two or more feet  26  extending from the bottom surface. Feet  26  prevent the trays from accumulating contaminants and protect the fragility of the protrusions  22  as well. When present, feet  26  have dimensions that do not interfere with any of the tray features on the top and bottom profiles of the present invention.  
         [0019]     The manner in which the contents of a tray are inverted will now be discussed.  FIG. 4A  shows a suspension strip  100  retained by protrusions  22  on a top side of a first tray  200 . A second tray  300  is stacked on the first tray  200  to capture strip  100  between protrusions  22  and retention rails  35 . When tray stack  400  in  FIG. 4B  is turned over, strip  100  undergoes minimal movement because of the proximity of the protrusions of adjacent trays  200 ,  300 . The minimal amount of movement is beneficial in reducing contaminant buildup in strip  100 . After turning over stack  400 , strip  100  has an orientation reverse from the orientation illustrated in  FIG. 4A .  FIG. 4B  illustrates the first orientation prior to inversion in which strip  100  is retained by protrusions  22  on tray  200 . Specifically, protrusions  22  receive a portion of the openings on suspension strip  100 . In the second and reverse orientation shown in  FIG. 4C , protrusions  22  on tray  300  receive a different portion of openings of suspension strip  100 .  
         [0020]     A partial exploded view of a suspension strip  100  between two trays is shown in  FIG. 5 . In this embodiment, a flexible circuit  125  is part of the suspension strip  100 . The flexible circuit  125  constitutes a narrow base having an electrical circuit attached thereon. Flexible circuit  125  is supported between two retention rails  35 . Specifically, a narrow space or clearance  75  between retention rails  35  ensures minimal rubbing between the flexible circuit and retention rails  35 . Because retention rails  35  are slender and easily bendable, they are provided with indentations  52  near gap  85 . Indentations  52  enable retention rails  35  to mate with notches  47  on alignment bars  44 . Alignment bars thereby stabilize retention rails  35  by preventing the retention rails  35  from bending unnecessarily. Notches  47  also secure locating rails  35  in a desired position. Therefore, retention rails  35  and locating rails  25  substantially restrict vertical movement of suspension strip  100 .  
         [0021]     The miniscule clearance  75  between retention rails  35  of each tray allows suspension strip  100  to be reoriented with minimal movement when a stack of trays is inverted. As a result of inverting the tray stack, the suspension strip is transferred with minimal movement to an abutting tray and reoriented to an orientation reverse from the orientation before inversion.  
         [0022]     The present invention is fabricated from traditional methods of injection molding. The present invention can be fabricated from conductive, thermoplastic, non-conductive, and insulated plastic. In addition, the trays of this invention can be fabricated from material that has electrostatic dissipating properties.  
         [0023]     The examples described herein are solely representative of the present invention. It is understood that various modifications and substitutions may be made to the foregoing examples without departing from either the spirit or scope of the invention. In some instances certain features of the invention wit[ be employed without other features depending on the particular situation encountered by the ordinary person skilled in the art. Moreover the trays are not restricted to handling solely strips having five suspension assemblies, but can hold more or fewer assemblies on a strip, as well as a plurality of strips within the same tray. It is therefore the intent that the invention not be limited to the particular examples disclosed herein.