Abstract:
An instrument holder usable in a tray for holding surgical instruments includes a housing that pivots about an axis between a closed position adjacent the floor of the tray and an open position angularly spaced from the tray floor. The holder may include a releasable locking mechanism to prevent the holder from shifting from its open position.

Description:
FIELD OF THE INVENTION 
   The invention disclosed herein relates to a tray for holding medical instruments such as surgical tools. 
   BACKGROUND OF THE INVENTION 
   Medical instruments such as surgical tools should be sterile when used in order to reduce unwanted infections. These sterilized instruments need to be readily accessible and within easy reach of the user when it is desired to use them. 
   SUMMARY OF THE INVENTION 
   The invention disclosed herein provides a holder for medical instrumentation. The holder includes a housing for the instrumentation that is pivotally shiftable about a pair of trunnions, which engage a pair of brackets attached to the floor of a tray. The housing may be pivotally shifted about the trunnions between a closed horizontal storage position generally adjacent the floor of the tray and an open vertical position in which the instruments are accessible for use. The trunnions and brackets cooperate with each other to releasably secure the housing in its open position. 
   An object of the invention is to provide a holder for medical instrumentation which will provide easy access to sterilized instruments when needed. 

   
     BRIEF DESCRIPTION OF THE DRAWINGS 
     These and other aspects of the invention will be apparent from the following description, with reference to the accompanying drawings, in which: 
       FIG. 1  shows an instrument holder of this invention in its closed position; 
       FIG. 2  shows the instrument holder of  FIG. 1  in a partially open position; 
       FIG. 3  is a side view of the instrument holder of  FIG. 1 ; 
       FIG. 4  is a side view of the partially open instrument holder of  FIG. 2 ; 
       FIG. 5  is a side view of the instrument holder of  FIG. 1  in its open position; 
       FIG. 6  shows a second embodiment of the instrument holder in its closed position; 
       FIG. 7  shows the instrument holder of  FIG. 6  in a partially open position; 
       FIG. 8  is a side view of the closed instrument holder of  FIG. 6 ; 
       FIG. 9  is a side view of the partially open instrument holder of  FIG. 7 ; 
       FIG. 10  is a side view of the instrument holder of  FIG. 6  in its open position; 
       FIG. 11  shows a third embodiment of the instrument holder in its closed position; 
       FIG. 12  shows the instrument holder of  FIG. 11  in a partially open position; 
       FIG. 13  is a side view of the closed instrument holder of  FIG. 11 ; 
       FIG. 14  is a side view of the partially open instrument holder of  FIG. 12 ; 
       FIG. 15  is a side view of the instrument holder of  FIG. 11  in its open position; 
       FIG. 16  shows a fourth embodiment of the instrument holder in its closed position 
       FIG. 17  shows the instrument holder of  FIG. 16  in a partially open position; 
       FIG. 18  shows the instrument holder of  FIG. 16  in its open position; and, 
       FIGS. 19A–19E  are detailed views of the pivot mechanism in successive positions between its closed position in  FIG. 19A  and its open position in  FIG. 19E . 
   

   DETAILED DESCRIPTION 
   Referring now to the drawings, an instrument holder  10  as depicted in  FIGS. 1–5  is used to carry medical instruments such as surgical tools. Instrument holder  10  is carried within a tray having a floor  12 . A pair of brackets  16  is provided for supporting a housing  18  which will carry the instrumentation. Each bracket  16  includes a wall  20  fitted upwardly through an opening  14  in floor  12  and a base  22  abutting and attached to the underside of tray floor  12 . Housing  18  is pivotally shiftable about a pair of trunnions  24  between a closed horizontal storage position adjacent to tray floor  12  (shown in  FIG. 3 ) and an open use position relative to the tray floor (shown in  FIG. 5 ). The open position of housing  18  is preferably approximately perpendicular to tray floor  12 . The closed position of housing  18  is preferably approximately parallel to tray floor  12 . 
   Housing  18  includes a generally box shaped frame  25  of sheet metal which supports two retention blocks  26 ,  28 . Front instrument retention block  26  spans the front open end of frame  25 , and rear instrument retention block  28  spans the rear open end of the frame. Retention blocks  26 ,  28  are preferably made of surgical grade machinable plastic, such as available under the trade name PROPYLUX™, or any other suitable machinable material. Retention blocks  26 ,  28  are spaced from each other and have a plurality of aligned instrument bores  30  for accepting various medical instrumentation (not shown). Instrument bores  30  are formed as through bores  32  in front retention block  26  and as closed ended or blind bores  34  in rear retention block  28 . Instrument bores  30  are generally parallel to frame  25  such that an instrument may be inserted into an instrument bore from the exterior side of front retention block  26  through a through bore  32  and into an aligned blind bore  34  in rear retention block  28 . The blind bore  34  prevents the instrument from falling out of instrument bore  30  when housing  18  is in its open position. 
   Trunnions  24  protruding from opposite sides of rear retention block  28  extend beyond frame  25 . In cross section, trunnions  24  are approximately semi-circular with a flat face  36  opposite the curved portion  38 . Trunnions  24  are fitted into corresponding openings  40  in bracket walls  20 . Each opening  40  is circular and provides a complementary journalled fit for the inserted trunnions  24  except for a slot  42  oriented perpendicular to floor  12  and having a cross sectional shape corresponding to the cross section of the trunnions. Each slot  42  extends downwardly from the bottom of each bracket hole  40  and accepts its trunnion  24  in an interference fit only when the trunnion&#39;s flat portion  36  is aligned with the corresponding flat portion of the slot. 
   A cam surface  44  is provided along each bracket wall  20  arcuately extending between a lower cradle  48  and an upper recessed cradle  50 . Cam followers  46  protrude outwardly from opposite sides of rear retention block  28  forwardly spaced from trunnions  24 . Cam followers  46  follow cam surface  44  when housing  18  is rotated about trunnions  24 , as described more particularly herein below. Cam follower  46  is preferably spaced from cam surface  44  in the lower portions of its travel between the open and closed positions to reduce frictional resistance of the pivot mechanism. Alternatively, cam followers  46  may slide along the entire cam surfaces  44  between lower cradle  48  when housing  18  is in its closed position and upper cradle  50  when the housing is in its open position. When housing  18  is in its closed position, cam followers  46  rest in lower cradles  48  and trunnions  24  are urged upwardly in opening  40  against bracket wall  20 , thereby supporting the cantilevered housing. 
   When housing  18  is in its open position, cam followers  46  rest in upper cradles  50 , which are recessed in relation to cam surfaces  44 . Upper cradles  50  are radially aligned above slots  42 , allowing the cam followers to shift downwardly from cam surface  44 , which thereby allows trunnions  24  to shift downwardly into slots  42  when housing  18  is in its open position. Upper cradles  50  also prevent housing  18  from shifting beyond its open position by obstructing cam follower  46 . When cam followers  46  are resting within recessed cradles  50  and trunnions  24  are fitted within slots  42 , housing  18  is maintained in its open position with the exterior side of rear retention block  28  preferably resting on tray floor  12  as shown in  FIG. 5  by the interference fit of the cam followers within the upper cradles and the flat faced trunnions  24  within the slots  42 . In practice, the tray will usually be placed on a horizontal surface such that gravity will urge housing  18 , cam followers  46 , and trunnions  24  downwardly into slots  42  and recessed saddle  50  when in its vertical open position. 
   To open housing  18 , a user grips a handle  52 , which protrudes outwardly from the front end of the housing, and tilts or pivots the housing upwardly about trunnions  24 . When cam followers  46  reach recessed upper cradles  50 , housing shifts downwardly such that the cam followers rest within the upper cradles and flat faced trunnions  24  are fitted into slots  42 . To close housing  18 , a user grips handle  52  and urges the housing in the reverse direction, or forwardly, tilting the housing downwardly about trunnions  24 . The user is not required to independently lift trunnions  24  out of slots  42 , but only needs to urge housing  18  horizontally. Cam surface  44  urges cam followers  46  upwardly out of recessed upper cradles  50 , which lifts trunnions  24  out of slots  42  in holes  40 , thereby allowing the housing to rotate freely about the trunnions. Housing  18  is then pivoted toward its closed position about trunnions  24  until cam followers  46  are again resting within lower cradles  42 . 
   A decorative plate—or name plate— 54  on the exterior side of housing  18  may be used for instructional, informational, or decorative inscriptions and the like. A pair of instrument holders  10  may be opposingly fitted into a tray with their front ends facing each other. 
   To use instrument holder  10 , instruments are inserted into aligned instrument bores  30  when the housing is in its open position. Housing  18  is then shifted to its closed position and the entire tray and instrument holder  10  may be sterilized. When it is desired to use the instruments, the tray is placed near the area of use, and housing  18  is shifted to its open position and locked as hereinbefore described. A user may then selectively remove instruments from instrument bores  30  as needed. 
   An alternative embodiment of instrument holder  10   a  is depicted in  FIGS. 6–10  with similar structures having the same numbers as hereinbefore assigned. In this embodiment, different sized instrument bores  30   a ,  30   b ,  30   c  in front and rear retention blocks  26   a ,  28   a  accommodate different sized instruments. 
   Another alternative embodiment of instrument holder  10   b  is depicted in  FIGS. 11–15  with similar structures having the same numbers as hereinbefore assigned. In this embodiment, a shorter housing  18   b  provides less space between front and rear retention blocks  26   b ,  28   b . Alternatively, a single retention block spanning the entire length of bores  30   d  could be used instead of separate front and rear retention blocks  26   b ,  28   b . Instrument holder  10   b  could be used to hold shorter instruments. 
   A further alternative embodiment of instrument holder  10   c  is depicted in  FIGS. 16–18  with similar structures assigned the same numbers as before. In this embodiment, steam holes  54  are located in frame  25   c  and through retention blocks  26   c ,  28   c . Smaller, circular bores  30   e  are regularly spaced in rows and columns for holding instruments. Feet  56  protruding downwardly from opposite ends of the front retention block  26   c  rest on tray floor  12  when housing  18   c  is in its closed position. Feet  56  may thereby be used to support housing  18  when closed such that housing is not cantilevered from trunnions  24  and cam followers  46  in the closed position. Steam holes  54  allow the passage of steam through housing  18  for sterilization. 
     FIGS. 19A–19E  show the preferred embodiment of the pivot mechanism shown on instrument holder  10   c  in successive positions between closed and open positions. In  FIG. 19A , the housing is in its closed position with cam follower  46  resting in lower cradle  48 . A trunnion  24   a  is carried within circular opening  40  in bracket wall  20 . A slot  42  extends downwardly from a lower portion of opening  40  in alignment with upper recessed cradle  50 . Trunnion  24   a  has a generally semi-circular cross-section that fits snuggly within circular opening  40 . Trunnion  24   a  includes a curved cut-away portion  36   a  opposite a circular portion  38 . Cut-away portion  36   a  of trunnion  24   a  allows the trunnion to slide into slot  42  only when the housing is in its open position, as shown in  FIG. 19E . 
   As the housing is shifted upwardly around trunnion  24   a , cam follower  46  is spaced from cam surface  44  in the lower portion of the cam follower&#39;s travel, as depicted in  FIG. 19B . As cam follower  46  nears upper portion of its travel, as shown in  FIG. 19C , the cam follower re-engages with cam surface  44  before reaching upper recessed cradle  50 . As cam follower  46  travels into upper cradle  50 , shown in  FIG. 19D , cut-away portion  36   a  of trunnion  24   a  aligns with slot  42  to allow the trunnion to slide into the slot as the cam follower slides into the upper recessed cradle. When the housing is completely open as depicted in  FIG. 19E , the back of housing  18  rests fully on tray floor  12 , trunnion  24   a  is fitted into slot  42 , and cam follower  46  is carried within upper cradle  50 . To close, the housing is urged horizontally in the reverse direction, thereby causing cam follower  46  to raise trunnion  24   a  out of slot  42  as it shifts out of upper cradle  50 . A slight space between trunnion  24   a  and slot  42  allows the trunnion to rotate slightly as cam follower  46  shifts out of upper cradle  50 . The housing may then be closed through reverse succession of the steps hereinbefore described. 
   The detailed description related herein is meant only to exemplify the invention to enable those skilled in the art to make and use it. It is not intended to be a limitation from other minor and obvious variations on the embodiments described, all of which variations are expressly included herein