Abstract:
A multiple level elevating cot adapted to be rolled into emergency vehicles, the cot having a wheeled undercarriage supporting a cot frame having a leading end and a trailing end, and adapted to selectively secure the cot frame in a plurality of elevational positions. The cot frame includes an improved drop frame having a wider range of motion to a cot construction. The cot frame is also provided with patient support features, such as positionable back, leg, and side arm supports.

Description:
BACKGROUND OF THE INVENTION  
       [0001]     This invention relates to ambulance cots and more particularly with improvements to multi-level roll-in cots capable of being used in different types of emergency vehicles having cot-receiving floors.  
         [0002]     Ambulance cots typically comprise an essentially rectangular patient support frame with wheeled collapsible-leg assemblies enabling the stretcher to be stowed or loaded into the back of an ambulance. Examples of such prior art cots are disclosed in U.S. Pat. Nos. 4,097,941, 4,192,541, 4,767,148, 5,537,700, and 5,575,026. Although the prior art cots have been generally adequate for their intended purposes, they have not been satisfactory in all aspects. For example, in a confidence space with obstacles such as tables, chairs and/or desks, maneuvering a lowered cot can still possess some difficulties to an operator.  
       SUMMARY OF THE INVENTION  
       [0003]     The present invention alleviates or at least ameliorates the above-mentioned difficulties by providing a simple arrangement that conveniently provides an improved drop frame having a wider range of motion to a cot construction. The cot construction of the present invention includes a cot frame supported by a stable wheeled undercarriage, which permit the cot frame to be raised and lowered to a plurality of positions of use. The cot frame is also provided with patient support features, such as positionable back, leg, and side arm supports.  
         [0004]     In one embodiment of the present invention, an elevating cot that is adapted to be rolled into emergency vehicles is disclosed. The cot comprises a generally rectangular cot frame, and a drop frame rotatably mounted to the cot frame. The drop frame is positionable in an extended position, and at least one position above the extended position.  
         [0005]     In another embodiment of the present invention, an elevating cot that is adapted to be rolled into emergency vehicles is disclosed. The cot comprises a generally rectangular undercarriage having wheels, a generally rectangular cot frame having a leading end and a trailing end, and leg members interconnecting the cot frame and the undercarriage. The cot further includes a drop frame rotatably mounted to the cot frame. The drop frame is positionable in an extended position, and at least one position above the extended position.  
         [0006]     These and other features and advantages of the invention will be more fully understood from the following description of some embodiments of the invention taken together with the accompanying drawings. It is noted that the scope of the claims is defined by the recitations therein, and not by the specific discussion of features and advantages set forth in the present description. 
     
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0007]     The present invention is illustrated by way of example and not limitation in the accompanying figures, in which like references indicate similar elements, and in which:  
         [0008]      FIG. 1  is a side view of a cot structure embodiment of the invention in an elevated position;  
         [0009]      FIG. 2  is a side view of the cot structure embodiment of  FIG. 1 , with a back support in a fully upright position and illustrating a drop frame with a wider range of motion then previously available in the prior art, the range of motion being indicated in dotted lines for purposes of illustration; and  
         [0010]      FIG. 3  is an enlarged fragmented perspective view of a portion of the drop frame according to the present invention. 
     
    
       [0011]     Skilled artisans appreciate that elements in the figures are illustrated for simplicity and clarity and have not necessarily been drawn to scale. For example, the dimensions of some of the elements in the figures may be exaggerated relative to other elements to help to improve understanding of embodiment(s) of the present invention.  
       DETAILED DESCRIPTION  
       [0012]     Referring first to  FIGS. 1 and 2 , illustrated is a cot structure embodiment of the invention indicated generally by symbol  100 . The cot  100  has a rectangular undercarriage  10  mounting pairs of swivel caster wheels  12  at its opposite ends. It is to be appreciated that only one of the sides of the cot structure is illustrated for convenience, as the opposite side is substantially identical to the side shown. The undercarriage  10  includes opposing side frame members  14 , which are interconnected by transverse frame members (not shown). Extending upwardly from the undercarriage  10  are pairs of cross forming frame members  16 ,  18 , which serve to interconnect the undercarriage  10  with a cot frame  20 .  
         [0013]     Cot frame  20  includes opposing tubular side frame members  22  interconnected at the foot or trailing end by a transverse tubular end member  24 . At their leading or forward ends, the side frame members  22  each terminate at a respective hinge pivot  26 . Supported between the pair of hinge pivots  26  is a transverse frame  28  having a drop frame  30  rotatably coupled thereto, which is best illustrated by  FIG. 3 .  
         [0014]     Drop frame  30  includes tubular side frame portions  32  and  34  joined at their forward ends by an end frame member  36  ( FIG. 1 ). In one embodiment, side frame portions  32  and  34 , and end frame member  36  are a unitary piece. The drop frame  30  is releasable engaged by the pair of hinge pivots  26 , which also limits the range of motion of drop frame  30 . In particular, rotation of drop frame  30  is arrested by a latching mechanism, which is generally indicated by symbol  38 . Latching mechanism  38  permits the drop frame  30  to be moved from the extended position  40 , as seen in  FIG. 1 , to an upper middle position  42 , to an upright position  44 , a lower middle position  46  or to a collapsed position  48  also shown in  FIG. 2 . The dashed lines in  FIG. 2  indicate the upper middle position  42 , the upright position  44 , and the lower middle position  46 .  
         [0015]     In one embodiment, the latching mechanism  38  includes a spring biased latch  50  which engages a respective one of slots  52  provided in each hinge pivot  26  to secure the drop frame  30  in either the extended position  40 , the upper middle position  42 , the upright position  44 , or the lower middle position  46 . The drop frame  30  hangs unsecured in the collapsed position  48 . A release handle  54  of the latching mechanism  38  is provided to the drop frame  30  which releases the sliding latch  50  from one of the slots  52 , such that the drop frame  30  may be repositioned if in the extended position  40 , the upper middle position  42 , the upright position  44 , or the lower middle position  46 .  
         [0016]     It is to be appreciated that positioning the drop frame  30  in the lower middle position  46  provides a lower lifting handle position for improved ergonomics when the cot is fully elevated. Additionally, with the cot  100  in a lowered position, positioning the drop frame  30  in the upper middle position  42  also provides a higher lifting handle position for improved ergonomics. It is further to be appreciated that in a confidence space with obstacles such as tables, chairs and/or desks, placing the drop frame  30  in either the upper middle position  42 , or the upright position  44 , permits more convenient maneuvering of the cot when fully elevated by elevating the drop frame  30  out of the way of such obstacles.  
         [0017]     The drop frame  30  is provided with a pair of loading wheels  56  projecting downwardly from the outermost ends of side frame sections. The loading wheels  56  are interconnected by a generally U-shaped tubular bail  58 . The bail  58  is spring biased by springs  60  to the downwardly extending position seen in  FIG. 1 , and is configured to engage a tongue-like floor fitting  62  mounted on the floor of the emergency vehicle. The bail  58  is deflected upwardly by a release arm  64  positioned adjacent both sides of the cot frame  20 , which permits the attendant to release the bail  58  from engagement with the floor fitting  26  when it is desired to remove the cot from the vehicle.  
         [0018]     It will be understood that the basic cot frame  20  may be provided with various adjustable features, such as folding side arms  66 , a multiple-position backrest  68 , and an adjustable leg section  70  for placing the patient in a shock position, which is illustrated by  FIG. 2 . As best seen by  FIG. 2 , the backrest  68  has a generally u-shaped frame member  72  hinged at its ends to a traverse frame member spanning between side frame members  22 , by means of pivot fittings  74 . The backrest  68  is movable from a reclined position shown in  FIG. 1 , to an upright position illustrated in  FIG. 2 , and a plurality of positions therebetween by a lifting device  76 . The lifting device  76  is pivotally attached at an upper end to a mount  80  of the backrest frame  68 . In the illustrated embodiment of  FIG. 1 , manipulation of a lever  82  causes the lifting device  76  to raise or lower the backrest  68  as desired.  
         [0019]     The adjustable leg section  70  is formed by u-shaped frame members  84  (partially shown in  FIG. 2 ) hinged at its ends to a transverse tubular member of the cot frame  20  (not shown) by hinge members  86 . At the opposed end of the frame member  84 , a footrest  88  is mounted. The leg section  70  is raised and lowered by latch members  90  of known construction. Other features also may be provided, such as an auxiliary bail-like end frame member  92  underlying end frame member  12 , which is positioned to be easily grasped by an attendant.  
         [0020]     Referring to  FIGS. 1 and 2 , the pairs of cross-forming frame members  16 ,  18  are pivotally connected by a pivot rod  94  at the point of intersection of the pairs of cross-forming frame members  16 ,  18 . In addition, the cross-forming frame members  18  telescopically receive tubular extensions  96  at their lowermost ends, which are pivotally connected to the undercarriage  10 . At their uppermost ends the cross-forming frame members  18  mount fittings  98  having guide pins  100 . The guide pins  100  are slidably received in a slot  102  of elongated guide members  104 . A hand release  106  when operated permits sliding of the guide pins  100  within the slots, which permits rising and lowering of the cot frame  20  relative to the undercarriage  10  to any one of a number of elevational positions or collapsed against the undercarriage  10 .  
         [0021]     In compliance with the statute, the invention has been described in language more or less specific as to structural and methodical features. It is to be understood, however, that the invention is not limited to the specific features shown and described, since the means herein disclosed comprise preferred forms of putting the invention into effect. The invention is therefore, claimed in any of its forms or modifications within the proper scope of the appended claims appropriately interpreted in accordance with the doctrine of equivalents. Any modification of the present invention that comes within the spirit and scope of the following claims should be considered part of the present invention.