Patent Publication Number: US-2009229639-A1

Title: Particle Purge System

Description:
BACKGROUND 
     A typical data storage system or disc drive includes a rigid housing that encloses a variety of components. The components can include a storage medium, usually in the form of one or more discs, having data surfaces for storage of digital information. The discs are mounted on a spindle motor that causes the discs to spin and the data surfaces of the discs to pass under aerodynamic bearing disc head sliders. The sliders carry transducers, which write information to and read information from the data surfaces of the discs. 
     One of the more prevalent reliability issues in disc drives are media failures caused by particles that contaminate the airflow in the housing of the disc drive. To increase recording area density, fly height is lowered and the disc is manufactured as smooth as possible. During disc drive operation, serious damage to the data surface of the disc and the sliders can result during lowered fly height if a particle were to become present between the disc and the slider. 
     Small and large particles released from drive components into the disc drive environment are unavoidable. Although disc drives employ recirculation filters to protect the disc from these particles, it is desirable to remove and quantify particles from the disc drive before the product is shipped to improve product quality and reliability. 
     SUMMARY 
     A particle purge system purges particles from an electronic device. The particle purge system includes an interface plate having a top surface and a bottom surface. The interface plate includes a continuous wall that protrudes from the top surface of the interface plate and has a perimeter that follows an opening in the electronic device. The continuous wall includes an inner facing surface and an outer facing surface. The interface plate also includes an inlet and an outlet. The inlet extends between the top and bottom surfaces of the interface plate and is located inside the perimeter defined by the continuous wall. The outlet extends between the top and bottom surfaces of the interface plate and is located inside the perimeter defined by the continuous wall. 
     The electronic device is inverted and secured to the interface plate. A clean purge fluid is injected into the inlet of the interface plate to release and remove particles. The particle purge system also includes an agitator for agitating the electronic device to enhance the release of particles into the purge fluid. The purge fluid that contains the released particles is exhausted through the outlet in the interface plate. 
     These and various other features and advantages will be apparent from a reading of the following Detailed Description. This Summary is not intended to identify key features or essential features of the claimed subject matter, nor is it intended to be used as an aid in determining the scope of the claimed subject matter. The claimed subject matter is not limited to implementations that solve any or all disadvantages noted in the background. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is a perspective view of a particle purge system in accordance with one embodiment. 
         FIG. 2  is a partial perspective view of the upper chamber of  FIG. 1 . 
         FIG. 3  is a bottom perspective view of the upper chamber illustrated in  FIG. 1  and illustrated partially in  FIG. 2 . 
         FIG. 4  is a top perspective view of the lower chamber of  FIG. 1 . 
         FIG. 5  is an exploded perspective view of the lower chamber illustrated in  FIGS. 1 and 4 . 
         FIG. 6  is an enlarged partial side view of the lower chamber illustrated in  FIGS. 1 ,  4  and  5 . 
         FIG. 7  is a top perspective view of a lower chamber of a purge system in accordance with another embodiment. 
         FIG. 8  illustrates an exploded perspective view of the lower chamber illustrated in  FIG. 7 . 
         FIG. 9  is a top perspective view of a lower chamber of a purge system in accordance with yet another embodiment. 
         FIG. 10  illustrates an exploded perspective view of the lower chamber illustrated in  FIG. 9 . 
         FIG. 11  is a top perspective view of a lower chamber of a purge system in accordance with yet another embodiment. 
         FIG. 12  illustrates an exploded perspective view of the lower chamber illustrated in  FIG. 11 . 
         FIG. 13  is a perspective view of a particle purge system in accordance with another embodiment. 
         FIG. 14  is a perspective view of the particle purge system of  FIG. 13  including an inverted base of a disc drive to be purged. 
         FIG. 15  is a process flow diagram illustrating a method of purging particles from an electronic device. 
     
    
    
     DETAILED DESCRIPTION 
     In accordance with embodiments discussed in detail below, a base of a data storage system or disc drive is assembled with drive components and then subjected to a particle purge using a particle purge system. The particle purge system exposes the assembled base to a specific orientation, a shock input, controlled air flow and controlled evacuation to remove particulates. Besides removing particle contamination to ensure product quality, the particle purge system can also provide for the quantification and qualification of particles removed. Such a metrology feature adds additional benefits for process manufacturing improvement. 
     Although embodiments of the particle purge system are discussed in terms of use for a base of a disc drive, it should be realized that the particle purge system can be used to remove particles and allow for the quantification and qualification of particles in other types of electronic devices. For example, particle purge system can be used in various computing devices such as mobile phones, music players, video players and personal digital assistants. The following description discusses example embodiments of a particle purge system. 
       FIG. 1  is a perspective view of a particle purge system  100  in accordance with one embodiment. Particle purge system  100  includes an upper chamber  102  coupled to a lower chamber  104  by an arm  105 . Lower chamber  104  is configured to support an inverted base  108  of a disc drive and deliver purge fluid to the base. Upper chamber  102  is configured to align and hold base  108  on lower chamber  104  as well as provide power to spin the disc(s) within the base and agitate the base to help loosen particles for removal. Upper chamber  102  moves along arm  105  between an active purge position and an inactive position. As illustrated in  FIG. 1 , upper chamber  102  is an inactive position. In an active position, an air cylinder attached to arm  105  lowers upper chamber  102  and forces the upper chamber to come into contact with base  108 . 
     Lower chamber  104  includes an interface plate  106  for allowing a base  108  of a disc drive to interface with particle purge system  100 . As previously discussed, although interface plate  106  is designed to interface with base  108 , interface plate  106  can be configured to interface with any of various types of electronic devices. Coupled to lower chamber  104  are a purge fluid inlet port  110  and an exhaust outlet port  112 . Inlet port  110  is configured to receive an injected fluid, such as clean dry air, to feed through lower chamber  104  and ultimately blow into base  108 . Outlet port  112  is configured to exhaust the injected fluid that contains particles released from base  108  to a metrology unit  114 . Metrology unit  114  is configured to qualify and quantify particles that are released and removed by the injected fluid from base  108 . Also coupled to lower chamber  104  is a pressure transducer  116  and adapter block  117 . Pressure transducer  116  provides information to a regulator for regulating the flow of purge fluid into inlet port  110 . In one embodiment, flow should be regulated such that a positive pressure is maintained in lower chamber  104  and a pressure differential is limited to approximately 1 PSI. 
       FIG. 2  illustrates a top perspective view of a portion of upper chamber  102  of the particle purge system  100  in  FIG. 1 . As illustrated in  FIG. 2 , some components of upper chamber  102  are located underneath the chamber and are illustratively shown in phantom lines.  FIG. 3  illustrates a bottom perspective view of upper chamber  102 . 
     Upper chamber  102  includes a motor  118  ( FIG. 2 ). Motor  118  is configured to provide repeatable agitation to an agitator pin  120  ( FIGS. 2 and 3 ). When upper chamber  102  is placed into an active position, agitator pin  120  comes into contact with base  108 . By agitating base  108  during a purge, an enhanced release of particles will occur. Upper chamber  102  also includes pogo pins  122  ( FIGS. 2 and 3 ) for connection to a spindle motor coupled to disc(s) assembled in base  108 . Pogo pins  122  provide power to the spindle motor such that the disc(s) can be spun under control while particles are purged from base  108 . 
     Upper chamber  102  also includes a plurality of datum rollers  124  and a plurality of hold down pins  126 . As illustrated, upper chamber  102  includes six datum rollers  124  ( FIGS. 2 and 3 ) and four hold pins  126  ( FIG. 3 ). Datum rollers  124  align base  108  with interface plate  106  while hold pins  126  provide a non-metallic contact between base  108  and upper chamber  102 . Example materials for hold pins  126  should exhibit properties that are well-suited for wear applications that otherwise would require a metal on metal contact. One example material is a polymer, such as Polyslick. However, other materials can be used. 
       FIG. 4  illustrates a perspective view of lower chamber  104  of  FIG. 1  while  FIG. 5  illustrates an exploded perspective view of lower chamber  104 . In  FIG. 4 , coupled to lower chamber  104  includes pressure transducer  116  and adapter block  117 , while in  FIG. 5  these components are removed. In both  FIGS. 4 and 5 , purge fluid inlet port  110  and exhaust outlet port  112  are illustrated with adapter block  113 . Base  108  of a disc drive is illustrated in  FIG. 5  exploded from interface plate  106 . However, base  108  in  FIG. 4  is removed to more clearly illustrate features of interface plate  106 . 
     As illustrated in  FIGS. 4 and 5 , lower chamber  104  includes a bottom plate  128 , a middle plate  130  and interface plate  106 . As previously discussed, interface plate  106  is configured to interface with base  108  of a disc drive. Interface plate  106  is configured to interface or come into contact with at least a portion of an upper surface  132  of base  108 . In other words, base  108  is inverted as illustrated in both  FIGS. 1 and 5  to interface with interface plate  106 . 
     With reference to  FIGS. 4 and 5 , interface plate  106  includes a top surface  134  and a bottom surface  136 . A continuous wall  138  extends from top surface  134  of interface plate  106  and has a perimeter that closely follows a profile and path of a gasket located on upper surface  132  of base  108 . A gasket generally surrounds an opening in upper surface  132  of base  108 . It should be realized that there are numerous profiles of which continuous wall  138  could follow depending upon the design of the base of the disc drive. Continuous wall  138  is just one example. 
     Continuous wall  138  includes an inner facing surface  140  and an outer facing surface  142 . Interface plate  106  also includes a plurality of supports  144 . Supports  144  protrude and extend from top surface  134  of interface plate  106 . Supports  144  are located outwardly from outer facing surface  142  of continuous wall  138  and are configured to support upper surface  132  of base  108 . Like hold pins  126  located on upper chamber  102  illustrated in  FIG. 3 , supports  144  should also be made of a material that exhibits properties well-suited for wear applications that otherwise would require a metal on metal contact. For example, a polymer, such as Polyslick can be a suitable material. However, other materials can be used. 
     Middle plate  130  includes a top surface  131  and a bottom surface  133 . Top surface  131  is coupleable to bottom surface  136  of interface plate  106 . As illustrated in  FIG. 5 , middle plate  130  includes a recessed area  146  for directing clean purge fluid for delivery to interface plate  106  and purge fluid returning from the interface plate that contains particles. The purge fluid that contains particles is an exhaust fluid that is to be exhausted to a metrology unit, such as metrology unit  114  ( FIG. 1 ), for particle quantification and qualification. Middle plate  130  also includes a plurality of slots  148  for use in exhausting purge fluid. As illustrated in  FIGS. 4 and 5 , middle plate  130  includes four slots  148 . Each slot is spaced apart and located outwardly from recessed area  146 . Each slot is also spaced apart and located outwardly from each side edge of interface plate  106  after the interface plate is attached to middle plate  130  as illustrated in  FIG. 4 . Slots  148  will be described in detail below in regards to the flow of fluid in particle purge system  100 . 
     Bottom plate  128  includes a top surface  129  that is coupleable to bottom surface  133  of middle plate  130 . As illustrated in  FIG. 5 , bottom plate  128  includes a recessed area  150  for receiving exhaust fluid to be exhausted through slots  148  in middle plate  130 . Fluid exhausted through slots  148  is directed outside of lower chamber  104  to the environment through a port  152 . 
       FIG. 5  illustrates the movement of fluid in lower chamber  104 . The filled arrows represent a clean purge fluid  155  and the open arrows represent an exhaust fluid  157 . In the embodiments illustrated, a clean purge fluid  155  is clean dry air. However, it should be realized that the fluid can be a variety of different types of gases or even liquids. To begin with, clean purge fluid  155  is injected into particle purge system  100  through inlet port  110 . The clean purge fluid  155  travels through adapter block  113  and into a middle plate inlet port  154 . The clean purge fluid  155  is directed within a channel  156 , which occupies a portion of recessed area  146  in middle plate  130 , and ultimately through an inlet in the form of inlet segments  158  in interface plate  106 . Channel  156  is shaped to follow or match a shape and location of inlet segments  158  and an outlet in the form of an outlet segment  160  in interface plate  106 . Clean purge fluid  155  is blown through inlet segments  158  into base  108  to release and remove particulates. Exhaust fluid  157  is evacuated through outlet segment  160  in interface plate  106  back towards middle plate  130 . 
       FIG. 6  illustrates an enlarged partial side view of lower chamber  104 , upper chamber  102  and base  108 . In  FIG. 6 , interface plate  106  and middle plate  130  of lower chamber  104  are partially illustrated, while datum rollers  124  are illustrated in the partial view of upper chamber  102 . In the example embodiment illustrated in  FIGS. 1-6 , base  108  is resting on supports  144  and not in contact with continuous wall  138 . Therefore, a portion of exhaust fluid  157  ( FIG. 5 ) can be lost to the environment through a gap  161  ( FIG. 6 ) between upper surface  132  of base  108  and continuous wall  138 . A remaining portion of exhaust fluid will be directed into recessed area  146  (outside of channel  156 ), through an outlet port  162  ( FIG. 5 ) into adapter block  113  ( FIG. 5 ) and ultimately through exhaust outlet port  112  ( FIGS. 1 and 5 ) to a metrology unit, such as metrology unit  114  ( FIG. 1 ). 
     The loss of exhaust fluid  157  through gap  161  ( FIG. 6 ) between continuous wall  138  and upper surface  132  of base  108  to the environment can occur in two forms. As indicated by the double open arrows illustrated adjacent the edges of interface plate  106  in  FIG. 5 , exhaust fluid  157  can exit directly to the environment. Exhaust fluid  157  can also be lost to the environment through slots  148  as indicated by the double open arrows that flow from middle plate  130  into bottom plate  128 . As previously discussed, fluid exhausted through slots  148  is directed into bottom plate  128  and outside of lower chamber  104  to the environment through port  152 . In one embodiment, port  152  can be connected to a vacuum such that the exhaust is forced outside of lower chamber  104 . 
       FIG. 7  is a top perspective view of a lower chamber  204  of a particle purge system in accordance with another embodiment. For example, lower chamber  204  can be used with particle purge system  100 . Like lower chamber  104  illustrated in FIGS.  1  and  4 - 6 , lower chamber  204  includes an interface plate  206 , a middle plate  230  and a bottom plate  228 . Interface plate  206 , middle plate  230  and bottom plate  228  are similar to interface plate  106 , middle plate  130  and bottom plate  128 . However, middle plate  230  and bottom plate  228  include features that are different from those features of middle plate  130  and bottom plate  128  as will be explained in detail in  FIG. 8 . 
       FIG. 8  illustrates an exploded perspective view of lower chamber  204  including interface plate  206 , middle plate  230  and bottom plate  228 . Interface plate  206  includes all of the same features as interface plate  206  including supports  244  for receiving an upper surface of a base of a disc drive. With supports  244 , a base of a disc drive will not contact continuous wall  238  and will be separated by a gap. As discussed in regards to interface plate  106 , continuous wall  238  of interface plate  206  matches a profile and path of a gasket on the upper surface of the base. The gasket generally surrounds an opening in the upper surface of the base. 
     Middle plate  230  includes a top surface  231  and a bottom surface  233 . Top surface  231  is coupleable to bottom surface  236  of interface plate  206 . As illustrated in  FIG. 8 , middle plate  230  includes a recessed area  246  for directing clean purge fluid for delivery to interface plate  206  and purge fluid returning from the interface plate that contains particles to be exhausted to a metrology unit, such as metrology unit  114  ( FIG. 1 ), for particle quantification and qualification. Recessed area  246  includes a channel  256  for delivering clean purge fluid to a base supported by supports  244  of interface plate  206 . Channel  256  occupies a portion of recessed area  246  and is shaped to follow or match a shape and location of an inlet in the form of inlet segments  258  and an outlet in the form of an outlet segment  260  in interface plate  206 . A remaining portion of recessed area  246  includes an aperture  264  extending between top surface  231  and bottom surface  233  of middle plate  230 . Aperture  264  exhausts fluid to a metrology unit. 
     Bottom plate  228  includes a top surface  229  that is coupleable to bottom surface  133  of middle plate  230 . As illustrated in  FIG. 8 , bottom plate  228  includes a recessed area  250  for receiving exhaust fluid to be exhausted through aperture  264  in middle plate  230 . Recessed area  250  is a tapered recess that funnels to a port  252  at a bottom end of bottom plate  228 . Fluid exhausted through aperture  264  is directed outside of lower chamber  204  to a metrology unit, such as unit  114  illustrated in FIG.  1 , through port  252 . Middle plate  230  includes aperture  264  in recessed area  246  that directs exhaust fluid downwards instead of through a side outlet, like outlet port  162  of middle plate  130 . Bottom plate  228  includes port  252  that also directs exhaust fluid downwards. These configurations are much better at exhausting particles from lower chamber  204  than exhausting particles from lower chamber  104 . Particles, especially larger sized particles, have difficulty following the bending pathways that are included in the embodiment illustrate in  FIGS. 4-5 . In addition, middle plate  230  does not need slots for directing exhaust fluid lost to the environment through a gap between the base and continuous wall  238 . Little exhaust fluid will escape through the gap between the base and continuous wall  238  because of the downward evacuation of exhaust fluid. 
       FIG. 8  also illustrates the movement of fluid in lower chamber  204 . The filled arrows represent a clean purge fluid  255  and the open arrows represent an exhaust fluid  257 . In the embodiments illustrated, clean purge fluid  255  is clean dry air. However, it should be realized that the fluid can be a variety of different types of gases or liquids. To begin with, clean purge fluid  255  is injected into lower chamber  204  through middle plate inlet port  254 . The clean purge fluid  255  is directed within channel  256 , which occupies a portion of recessed area  246  in middle plate  230 , and ultimately through inlet segments  258  in interface plate  206 . Through inlet segments  258 , clean purge fluid  255  is blown into a base that is resting on supports  244  to release and remove particulates. Exhaust fluid  257  is evacuated through outlet segment  260  in interface plate  206 , through aperture  264  of middle plate  230  to a metrology unit through port  252 . 
       FIG. 9  is a top perspective view of a lower chamber  304  of a particle purge system in accordance with yet another embodiment. For example, lower chamber  304  can be used with particle purge system  100 . Like lower chambers  104  (FIGS.  1  and  4 - 6 ) and  204  ( FIGS. 7-8 ), lower chamber  304  includes an interface plate  306 , a middle plate  330  and a bottom plate  328 . Interface plate  306 , middle plate  330  and bottom plate  328  are similar to interface plates  106  and  206 , middle plates  130  and  230  and bottom plates  128  and  228 . However, interface plate  206  and middle plate  330  include features that are different from those features of interface plate  206  and middle plate  230  as ill be explained in detail in  FIG. 10 . 
       FIG. 10  illustrates an exploded perspective view of lower chamber  304  including interface plate  306 , middle plate  330  and bottom plate  328 . Interface plate  306  includes similar features as interface plates  106  and  206  including supports  344  for receiving an upper surface of a base of a disc drive such that the base is not in contact with continuous wall  338  and is separated by a gap. However, interface plate  306  also includes an outlet aperture  370  extending between a top surface  334  and a bottom surface  336  of interface plate  306  instead of an outlet segment, such as outlet segments  160  and  260  of interface plates  106  and  206 . As discussed in regards to interface plate  106 , continuous wall  338  of interface plate  306  matches a profile of a gasket on the upper surface of the base. The gasket generally surrounds an opening in the upper surface of the base. 
     Middle plate  330  includes a top surface  331  and a bottom surface  333 . Top surface  331  is coupleable to bottom surface  336  of interface plate  306 . As illustrated in  FIG. 10 , middle plate  330  includes a recessed area  346  for directing clean purge fluid for delivery to interface plate  306  and purge fluid returning from the interface plate that contains particles to be exhausted to a metrology unit, such as metrology unit  114  ( FIG. 1 ), for particle quantification and qualification. Recessed area  346  includes a channel  356  for delivering clean purge fluid to a base supported by supports  344  of interface plate  306 . Channel  356  occupies a portion of recessed area  346  and is shaped to follow or match a shape and location of an inlet in the form of inlet segments  358  and outlet aperture  370 . Like middle plate  230 , a remaining portion of recessed area  346  includes an aperture  364  extending between top surface  331  and bottom surface  333 . Aperture  364  exhausts fluid to a metrology unit. 
     Bottom plate  328  includes a top surface  229  that is coupleable to bottom surface  333  of middle plate  330 . As illustrated in  FIG. 10 , bottom plate  328  includes a recessed area  350  for receiving exhaust fluid to be exhausted through aperture  364  in middle plate  330 . Recessed area  350  is a tapered recess that funnels to a port  352 . Fluid exhausted through aperture  364  is directed outside of lower chamber  304  to a metrology unit, such as unit  114  illustrated in  FIG. 1 , through port  352  at a bottom end of bottom plate  328 . Middle plate  330  includes aperture  364  in recessed area  346  that directs exhaust fluid downwards instead of through a side outlet, like outlet port  162  of middle plate  130 . Bottom plate  328  includes port  352  that also directs exhaust fluid downwards. These configurations are much better at exhausting particles from lower chamber  204  than exhausting particles from lower chamber  104 . Particles, especially larger sized particles have difficulty following the bending pathways that are included in the embodiment illustrate in  FIGS. 4-5 . In addition, middle plate  330  does not need slots for directing exhaust fluid lost to the environment through a gap between the base and continuous wall  338 . Little exhaust fluid will escape through the gap between the base and continuous wall  338  because of the downward evacuation of exhaust fluid. 
       FIG. 10  also illustrates the movement of fluid in lower chamber  304 . The filled arrows represent a clean purge fluid  355  and the open arrows represent an exhaust fluid  357 . In the embodiments illustrated, clean purge fluid  355  is clean dry air. However, it should be realized that the fluid can be a variety of different types of gases or even liquids. To begin with, clean purge fluid  355  is injected into lower chamber  304  through middle plate inlet port  354 . The clean purge fluid  355  is directed within channel  356 , which occupies a portion of recessed area  346  in middle plate  330 , and ultimately through inlet segments  358  in interface plate  206 . Through inlet segments  358 , clean purge fluid  355  is blown into a base that is resting on supports  344  to release and remove particulates. Exhaust fluid  357  is exhausted through outlet aperture  370  in interface plate  306 , through aperture  364  of middle plate  330  to a metrology unit through port  352 . 
       FIG. 11  is a top perspective view of a lower chamber  404  of a particle purge system in accordance with yet another embodiment. For example, lower chamber  404  can be used with particle purge system  100 . Like lower chambers  104  (FIGS.  1  and  4 - 6 ),  204  ( FIGS. 7-8 ) and  304  ( FIGS. 9-10 ), lower chamber  404  includes an interface plate  406 , a middle plate  430  and a bottom plate  428 . Interface plate  406 , middle plate  430  and bottom plate  428  are similar to interface plates  106 ,  206  and  306 , middle plates  130 ,  230  and  330  and bottom plates  128 ,  228  and  328 . However, interface plate  206  includes features that are different from those features of interface plate  306  as will be explained in detail in  FIG. 12 . 
       FIG. 12  illustrates an exploded perspective view of lower chamber  404  including interface plate  406 , middle plate  430  and bottom plate  428 . Interface plate  406  includes some similar features as interface plate  306  including an exhaust aperture  470 . Unlike interface plates  106 ,  206  and  306 , interface plate  406  does not include supports for receiving and supporting a base of disc drive. Instead, continuous wall  438  that protrudes from top surface  434  of interface plate  406  is configured to seal with a gasket on an upper surface of the base. The gasket generally surrounds an opening in the upper surface of the base. 
     Middle plate  430  includes a top surface  431  and a bottom surface  433 . Top surface  331  is coupleable to bottom surface  336  of interface plate  406 . As illustrated in  FIG. 12 , middle plate  430  includes a recessed area  446  for directing clean purge fluid for delivery to interface plate  306  and purge fluid returning from the interface plate contains particles to be exhausted to a metrology unit, such as metrology unit  114  ( FIG. 1 ), for particle quantification and qualification. Recessed area  446  includes a channel  456  for delivering clean purge fluid to a base that is sealed to continuous wall  438  of interface plate  406 . Channel  456  occupies a portion of recessed area  446  and is shaped to follow or match a shape and location of an inlet in the form of inlet segments  458  and an outlet in the form of outlet aperture  470  of interface plate  206 . Like middle plates  230  and  330 , a remaining portion of recessed area  446  includes an aperture  464  extending between top surface  431  and bottom surface  433  of middle plate  430 . Aperture  464  exhausts fluid to a metrology unit. 
     Bottom plate  428  includes a top surface  329  that is coupleable to bottom surface  433  of middle plate  430 . As illustrated in  FIG. 12 , bottom plate  428  includes a recessed area  450  for receiving exhaust fluid to be exhausted through aperture  464  in middle plate  430 . Recessed area  450  is a tapered recess that funnels to a port  452  at a bottom end of bottom plate  328 . Fluid exhausted through aperture  464  is directed outside of lower chamber  404  to a metrology unit, such as unit  114  illustrated in  FIG. 1 , through port  452 . Interface plate  406  is sealed to an upper surface of a base, middle plate  430  includes aperture  464  in recessed area  446  that directs exhaust fluid downwards instead of through a side outlet, like outlet port  162  of middle plate  130 . Bottom plate  428  includes port  452  that also direct exhaust fluid downwards. These configurations are much better at exhausting particles from lower chamber  404  than exhausting particles from lower chamber  104 . Particles, especially larger sized particles, have difficulty following the bending pathways that are included in the embodiment illustrate in  FIGS. 4-5 . In addition, middle plate  430  does not need slots for directing exhaust fluid lost to the environment because of the downward evacuation of the exhaust fluid. 
       FIG. 12  also illustrates the movement of fluid in lower chamber  404 . The filled arrows represent a clean purge fluid  455  and the open arrows represent an exhaust fluid  457 . In the embodiments illustrated, clean purge fluid  455  is clean dry air. However, it should be realized that the fluid can be a variety of different types of gases or even liquids. To begin with, clean purge fluid  455  is injected into lower chamber  404  through middle plate inlet port  454 . The clean purge fluid  455  is directed within channel  456 , which occupies a portion of recessed area  446  in middle plate  430 , and ultimately through inlet segments  458  in interface plate  406 . Through inlet segments  458 , clean purge fluid  455  is blown into a base that is sealed to continuous wall  438  to thereby release and remove particulates. Exhaust fluid is evacuated through outlet aperture  470  in interface plate  406 , through aperture  464  of middle plate  430  to a metrology unit through port  452 . 
       FIGS. 13 and 14  are top perspective views of a particle purge system  500  in accordance with another embodiment.  FIG. 13  illustrates particle purge system  500  without a mounted base of a disc drive and  FIG. 14  illustrates particle purge system  500  with a mounted base. Particle purge system  500  includes an interface plate  506  and an upper arm  572 . Interface plate  506  is configured to support an inverted base  508  of a disc drive and deliver clean purge fluid to the base. Upper arm  572  is configured to hold base  508  in an active purge position on interface plate  506  as well as provide power to spin the media within the base. 
     Although interface plate  506  is designed to interface with base  508 , interface plate  506  can be configured to interface with any of various types of electronic devices. Interface plate  506  includes guide blocks  574  and a continuous wall  538 . Continuous wall  538  extends from top surface  534  of interface plate  506  and has a perimeter that closely follows a profile of a gasket located on upper surface  532  of base  508 . The gasket generally surrounds an opening in upper surface  532  of the base. Continuous wall  538  includes an inner facing surface  540  and an outwardly facing surface  542 . Interface plate  506  includes four guide blocks  574  located at each corner outwardly from outwardly facing surface  542  around continuous wall  538  to both support an upper surface  532  of base  508  as well as align the base with interface plate  506 . Example materials for guide blocks  574  should exhibit properties that are well-suited for wear applications that otherwise would require a metal on metal contact. One example material is a polymer, such as Polyslick. However, other materials can be used. Interface plate  506  also includes an agitator  519  for agitating base  508  to help loosen particles for removal. 
     Under interface plate  506 , a clean purge fluid, such as clean dry air, is injected into purge particle system  500  through an inlet port  510 . However, it should be realized that the fluid can be a variety of different types of gases or even liquids. The clean purge fluid travels from inlet port  510  through an optional ionizer (hidden from view) and ultimately through an inlet in the form of an inlet segment  558  in interface plate  506 . Through inlet segment  558 , purge fluid is blown into base  508  to release and remove particulates. 
     Exhaust fluid that contains the released particles is then exhausted from base  508  by exiting base  508  through an outlet in the form of outlet segments  560  in interface plate  106  to an exhaust port (hidden from view) underneath interface plate  506 . The exhaust port is configured to exhaust the fluid to a metrology unit, such as metrology unit  114  ( FIG. 1 ). The metrology unit is configured to qualify and quantify particles that are being removed or purged from base  508 . In the embodiment illustrated in  FIGS. 13-14 , base  508  is resting on guide block  574  and not in contact with continuous wall  538 . Therefore, a portion of exhaust fluid can be lost to the environment through a gap between upper surface  532  of base  508  and continuous wall  538 . 
       FIG. 15  illustrates a process flow diagram  675  illustrating the flow of fluid for a method of purging particles from an electronic device, such as a base of a disc drive. At block  680 , a clean purge fluid  655  enters a pre-filter stack  682 . As discussed above, purge fluid can be any type of gas or liquid for use in purging contaminates from an electronic device. For example, purge fluid  655  can be clean dry air. At pre-filter stack  682 , any contaminates that have yet to be taken out of clean purge fluid  655  are filtered out. 
     Clean purge fluid  655  then enters a flow control system  682 . At flow control system  682 , clean purge fluid  655  is regulated to a particular flow rate with the use of a regulator. The flow rate is determined based on a pressure transducer included in the particle purge system  600 . The flow rate is selectable based on maintaining a positive pressure in particle purge system  600 . Clean purge fluid  655  then enters a final filter stack  684 . Final filter stack  684  ensures that no new contaminates have been introduced since the regulation of flow. 
     Purge fluid  655  then optionally enters an ionizer  686 . Ionizer  686  is an optional implementation to ensure that no static charges exists in the clean purge fluid. Finally, clean purge fluid  655  enters particle purge system  600  to release and remove particle contamination from an electronic device that is coupled to the particle purge system  600 . To enhance particle removal, especially in a disc drive embodiment, particle purge system  600  operates and controls the spin of a spindle motor that rotates the media as well as agitates the base to help loosen particles without degrading the disc drive. 
     After purge fluid  655  has purged the electronic device, the purge fluid that contains particles is exhausted. In the embodiments illustrated in  FIGS. 1-10  and  13 - 14 , there are two forms of exhaust fluid since the base of the disc drive is not sealed to particle purge system or that the outlet port is not at bottom end of the purge system. The first form of exhaust fluid  688  is vented to the environment. The second form of exhaust fluid  690  is vented to a metrology unit  614  for particle quantification and qualification. 
     It is to be understood that even though numerous characteristics and advantages of various embodiments of the invention have been set forth in the foregoing description, together with details of the structure and function of various embodiments, this disclosure is illustrative only, and changes may be made in detail, especially in matters of structure and arrangement of parts within the principles of the disclosure to the full extent indicated by the broad general meaning of the terms in which the appended claims are expressed. For example, the particular elements may vary depending on the type of electronic device that is to be purged while maintaining substantially the same functionality without departing from the scope and spirit of the present invention. In addition, although the preferred embodiment described herein is directed to purging a base of a disc drive, it will be appreciated by those skilled in the art that the teachings of the present invention can be applied to other components of other types of electronic devices, without departing from the scope and spirit of the present invention.