Abstract:
A footswitch having an adjustable treadle and switch placements, thereby helping to make the footswitch ergonomically more correct for a variety of users.

Description:
[0001]    This application claims the benefit of U.S. Provisional Patent Application Serial No. 60/408,211, filed Sep. 4, 2002, and is a continuation in part of U.S. patent application Ser. No. 29/166,339, filed Aug. 26, 2002, currently co-pending. 
     
    
     
       BACKGROUND OF THE INVENTION  
         [0002]    This invention relates generally to the field of surgical consoles and, more particularly, to footswitches used to control microsurgical consoles.  
           [0003]    During modern surgery, particularly ophthalmic surgery, the surgeon uses a variety of pneumatic and electronically driven microsurgical handpieces. The handpieces are operated by a microprocessor-driven surgical console that receives inputs from the surgeon or an assistant by a variety of peripheral devices including footswitches. Prior art footswitches are disclosed in U.S. Pat. Nos. 4,837,857 (Scheller, et al.), 4,965,417 (Massie), 4,983,901 (Lehmer), 5,091,656 (Gahn), 5,268,624 (Zanger), 5,554,894 (Sepielli), 5,580,347 (Reimels), 5,635,777 (Telymonde, et al.), 5,787,760 (Thorlakson), 5,983,749 (Holtorf) and 6,179,829 B1 (Bisch, et al.) and International Patent Application Publication Nos. WO 98/08442 (Bisch, et al.), WO 00/12037 (Chen) and WO 02/01310 (Chen), the entire contents of which being incorporated herein by reference. These patents, however, focus primarily on functional attributes of footswitches, not the ergonomics of footswitches.  
           [0004]    Accordingly, a need continues to exist for an ergonomically improved footswitch.  
         BRIEF SUMMARY OF THE INVENTION  
         [0005]    The present invention improves upon the prior art surgical footswitches by providing a footswitch having an adjustable treadle and switch placements, thereby helping to make the footswitch ergonomically more correct for a variety of users.  
           [0006]    Accordingly, one objective of the present invention is to provide a surgical footswitch that can be adjusted to accommodate different sized feet.  
           [0007]    Another objective of the present invention is to provide an ergonomically adjustable surgical footswitch.  
           [0008]    Another objective of the present invention is to provide a surgical footswitch having adjustable switches.  
           [0009]    These and other advantages and objectives of the present invention will become apparent from the detailed description and claims that follow. 
       
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0010]    [0010]FIG. 1 is a perspective view of the surgical footswitch of the present invention.  
         [0011]    FIGS.  2 A- 2 C are enlarged plan views of the footswitch of the present invention illustrating the adjustability of the side switches.  
         [0012]    [0012]FIG. 3 is an exploded perspective view of the surgical footswitch illustrating the assembly of the side switches.  
         [0013]    FIGS.  4 A- 4 B are bottom plan views of the side switches that may be used with the footswitch of the present invention illustrating the operation of the rotational locking mechanism.  
         [0014]    [0014]FIG. 5 is a top plan view of the footswitch of the present invention.  
         [0015]    [0015]FIG. 6 is an exploded assembly drawing of the heel cup slide adjustment mechanism that may be used with the footswitch of the present invention.  
         [0016]    FIGS.  7 A- 7 B are top plan views of the heel cup that may be used with the footswitch of the present invention illustrating the operation of the slidable heel cup adjustment mechanism.  
         [0017]    [0017]FIG. 8 is a top plan view of the footswitch of the present invention similar to FIG. 6, but illustrating the rotational operation of the treadle.  
         [0018]    FIGS.  9 A- 9 B are bottom plan views of the treadle switches that may be used with the footswitch of the present invention.  
         [0019]    [0019]FIG. 10 is a side partial cross-sectional view of the footswitch of the present invention illustrating the location of the treadle pivot point with respect to the ankle of the user.  
         [0020]    FIGS.  11 A- 11 B are side plan view of the footswitch of the present invention illustrating the operation of the treadle rotation lock.  
         [0021]    [0021]FIG. 12 is a top plan view of the footswitch of the present invention similar to FIGS. 6 and 8, but illustrating the rotational operation of the heel cup.  
         [0022]    [0022]FIG. 13 is an exploded assembly drawing of the heel cup rotation mechanism.  
         [0023]    [0023]FIG. 14 is a bottom plan view of the footswitch of the present invention.  
         [0024]    FIGS.  15 A- 15 C are cross-sectional view of the footswitch of the present invention illustrating the operation of the anti-gravity spring plunger feet. 
     
    
     DETAILED DESCRIPTION OF THE INVENTION  
       [0025]    As best seen in FIG. 1, footswitch  10  of the present invention generally includes base  12 , treadle  14  having heel cup  16  and side or wing switches  18 , all of which can be made from any suitable material, such as stainless steel, titanium or plastic. Base  12  may contain protective bumper  20  made from a relatively soft elastomeric material. As best seen in FIGS.  2 A- 2 C,  3  and  4 A- 4 B, side switches  18  may be adjusted inwardly (FIG. 2B) or outwardly (FIG. 2C) to increase or decrease the distance between switches  18  and accommodate for variations in the width of user foot  100 . Such adjustment is accomplished by pushing on locking buttons  22 , causing locking pin  24  on base  12  to be released from within detents  26  in switches  18  and rotating about pins  28  in holes  30  located on base  12 . When buttons  22  are released, springs  32  push detents  26  against locking pin  24 , thereby holding switches  18  in a locked position. The relative position of switches  18  may be determined visually by the use of switch position indicators  34 , as best seen in FIGS. 2B and 2C.  
         [0026]    As best seen in FIGS. 5, 6 and  7 A- 7 B, the length of treadle  14  may be adjusted by sliding movement of heel cup  16 . As best seen in FIG. 6, treadle  14  is mounted to treadle base  36  by thrust bearing  38 , thereby allowing treadle  14  to pivot about axis  40 . Heel cup slide  42  is received on treadle  14  and contains locking lever  44 , which is held onto heel cup slide  42  by retainers  46 . Locking pins  48  are held within locking lever  44  by shafts  50 . Locking pins  48  are biased into locking pin holes  52  in treadle  14  by springs  54  pushing against locking pin retainer  56 . In this manner, pushing on locking lever  44  pulls locking pins  48  out of locking pin holes  52  and allows heel cup slide  42  to slide lengthwise along slots  58  in treadle  14  as illustrated in FIGS.  7 A- 7 B. The relative position of heel cup  16  relative to treadle  14  may be visually indicated by indicators  60 . In addition, treadle  14  may contain raised reference point  62 , indicating the center oftreadle  14 .  
         [0027]    The width and length adjustments described above preferably allow footswitch  10  to be adjusted to accommodate the 5 th  percentile female to the 95 th  percentile male foot width and length, with or without shoes. As best seen in FIG. 10, ankle rotation axis  65  of foot  100  is located behind pivot axis  68  of treadle  14  for all three treadle lengths.  
         [0028]    As best seen in FIGS. 8 and 9A- 9 B, treadle  14  may rotate or counter-rotate about thrust bearing  38  to operate left and right switches  64 , which are mounted on treadle base  36 . Return springs  66  provide for automatic centering of treadle  14  following rotation. As best seen in FIGS. 11A and 11B, treadle base  36  contains alignment pin  70  hat fits within hole  72  in base  12  when treadle  14  is in the resting, non-pivoted position. Such a construction prevent rotation of treadle  14  to activation switches  64  when treadle is in the resting, non-pivoted position (FIG. 11A), but allows rotation of treadle  14  when treadle  14  is depressed or pivoted (FIG. 11B).  
         [0029]    As shown in FIGS. 12 and 13, heel cup  16  is mounted to heel cup slide  42  using thrust bearing  74 , alignment cap  76  and screws  82 . Such a construction allow for the rotation of heel cup  16  independently of any rotation of treadle  14  (as show in FIGS. 8 and 9A- 9 B) and allows for the operation of side switches  18  when treadle is in the resting and rotationally locked position (FIG. 11A). Return lever,  78 , mounted to heel cup  16  acts against return springs  80  to provide for automatic centering of heel cup  16  in the resting position.  
         [0030]    As shown in FIGS. 14 and 15A- 15 C, bottom  85  of base  12  preferably is covered by relatively high friction polymer (e.g., VERSAFLEX TPE) material  84  and contains a plurality of retractable, anti-gravity spring-loaded plunger feet  86  made from a low friction polymer material (e.g., DELRIN® acetal resin). As shown in FIG. 15A and 15B, when there is no weight on footswitch  10 , spring loaded plunger  86  project a short distance D (e.g., 0.04 inches) outwardly from bottom  84 , thereby contacting the floor and allowing easy sliding of footswitch  10  on relatively low friction plunger tips  88 . As shown in FIG. 15C, when weight is placed on footswitch  10 , plungers  86  retract, and high friction bottom  84  contacts the floor, thereby making it more difficult to slide footswitch  10  during use.  
         [0031]    This description is given for purposes of illustration and explanation. It will be apparent to those skilled in the relevant art that modifications may be made to the invention as herein described without departing from its scope or spirit.