Abstract:
An injection-molded housing for a handheld portable electronic device employs a minimal number of parts. The housing, made of a thermoplastic elastomer, is watertight, buoyant and exceptionally rugged. Principal components of the housing snap together without the need for adhesive bonding or fasteners using a tongue-and-groove closure mechanism.

Description:
BACKGROUND OF THE INVENTION 
   1. Field of the Invention 
   The present invention relates generally to the field of housings for electronic devices. More particularly, the invention is a hermetically sealed housing for a portable handheld reader/scanner. 
   2. Prior Art 
   Animal identification systems increasingly use electronic tags. Such tags offer numerous advantages over conventional tags, particularly in the amount of data that can be stored and retrieved with a reader. 
   Readers for electronic animal identification tags are relatively complex electronic devices, particularly if designed to operate with a variety of identification protocols. To be useful in the field, a portable reader must withstand a wide range of environmental conditions, including moisture, dust, physical abuse, etc. The housing should therefore be hermetically sealed to protect the electronic components. A portable reader/scanner should also be lightweight and ergonomically designed. 
   SUMMARY OF THE INVENTION 
   The present invention provides a lightweight, ergonomic handheld portable device designed for ambidextrous use. An injection-molded housing employs a minimal number of parts and is hermetically sealed without the use of adhesives to join the component parts. 
   In an exemplary embodiment, the present invention provides a portable handheld scanner comprising a one-piece hollow body portion, a scan face and a handle end cap. The body portion and the scan face snap together without the need for adhesive bonding or fasteners using a tongue-and-groove closure mechanism. 

   
     BRIEF DESCRIPTION OF THE DRAWINGS 
       FIG. 1  is a perspective view of a portable handheld scanner housing constructed in accordance with the present invention. 
       FIG. 2  is an exploded view of the housing of  FIG. 1 . 
       FIG. 3  is a partial cross-sectional view taken through line  3 — 3  of  FIG. 1 . 
   

   DETAILED DESCRIPTION OF THE INVENTION 
   In the following description, for purposes of explanation and not limitation, specific details are set forth in order to provide a thorough understanding of the present invention. However, it will be apparent to one skilled in the art that the present invention may be practiced in other embodiments that depart from these specific details. In other instances, detailed descriptions of well-known methods and devices are omitted so as to not obscure the description of the present invention with unnecessary detail. 
     FIG. 1  illustrates an exemplary embodiment of the present invention. A portable handheld reader/scanner  10  has a hollow body portion  12  which consists of an electronics enclosure portion  14  and a barrel-grip handle portion  16 . Body portion  12  is made as a single part rather than as two joined halves. This eliminates the need for bonding or otherwise joining two halves and also eliminates the presence of an unattractive seam line. The electronics enclosure portion  14  is closed off with scan face  18 , and the handle portion is closed off with end cap  20 . Controls and displays for the operation of reader/scanner  10  are provided on the top surface of enclosure portion  14 . These include a light-emitting diode (LED) indicator  22 , a liquid crystal display (LCD) alphanumeric display panel  24 , menu and scroll buttons  26  and a power on/read button  28 . Control buttons  26  and  28  are disposed for ease of operation by the thumb of a user, regardless of which hand reader/scanner  10  is held in. 
   Referring now to  FIG. 2 , the major components of reader/scanner  10  are shown in an exploded view. Scan face  18  snaps onto body portion  12  as will be more fully described below. A gasket  30  is applied around the perimeter of scan face  18  to aid in achieving a hermetic seal. End cap  20  attaches to the rear of body portion  12  with captive screw  32  which engages a threaded receptacle (not shown) in handle portion  16 . Gasket  34  is applied to the interface between end cap  20  and handle portion  16  to achieve a hermetic seal. Handle portion  16  is conveniently used as a compartment for batteries  36 . 
   Body portion  12 , scan face  18  and end cap  20  are preferably made of a themoplastic elastomer such as Santoprene® manufactured by Advanced Elastomer Systems of Akron, Ohio. This produces a housing that is watertight, buoyant and exceptionally rugged. The surface of the housing has a non-slip gripping quality even when wet and will not crack or chip, even when dropped onto concrete from a height of two meters. 
   The final assembly of reader/scanner  10  is accomplished with ease and at low cost. An internal electronics printed circuit board (not shown) installs into slots integrally molded in enclosure portion  12 . An antenna coil (also not shown) snaps into scan face  18  without fasteners. The body portion and scan face snap together and the end cap is attached with a single captive screw. 
     FIG. 3  illustrates details of the mechanism for attaching scan face  18  to body portion  12 . A tongue-and-groove attachment mechanism is employed which takes advantage of the elastomeric properties of the Santoprene® material. Body portion  12  has a “T” shaped tongue  40  that mates with groove  42  in the perimeter of scan face  18 . Owing to the resiliency of the material of which scan face  18  is made, tongue  40  snaps into groove  42  in a manner similar to the sealing mechanism widely used for plastic storage bags. A suitable seal can be achieved without the use of a separate gasket; however, gasket  30  may be applied around tongue element  40  to improve the hermeticity of the seal. 
   It will be recognized that the above described invention may be embodied in other specific  20  forms without departing from the spirit or essential characteristics of the disclosure. Thus, it is understood that the invention is not to be limited by the foregoing illustrative details, but rather is to be defined by the appended claims.