Abstract:
The present invention provides an extendable and retractable foot section for a medical examination table whereby the footrest is adapted to extend when the footrest section is raised to its generally horizontal height for use, and alternatively, retract when the footrest section is lowered to its generally vertical position for storage. The coordinated movement of the footrest section is accomplished through the use of a linkage assembly, a slidable footrest section, and a table footrest support frame. Additionally, an actuator is provided to operably cause the linkage assembly to rotate the footrest support frame while simultaneously sliding the footrest.

Description:
FIELD OF THE INVENTION 
   The present invention relates to medical examination tables in general, and more particularly to the footrest section therefor. 
   BACKGROUND OF THE INVENTION 
   Footrests for various types of chairs and medical examination tables are well known. Many times, the footrest will be attached to the chair or table in such a way as to allow it to be retracted when not in use. Typically, a footrest in the retracted position will be stored in a generally vertical position and when in use, will be positioned in a generally horizontal position. Various systems have been designed to either manually or automatically move the footrest from the generally vertically retracted or stored position to the generally horizontal position for use. 
   With an increasing aging population, the need for a medical examination table to accommodate the mobility needs of elderly patients has created the need for medical examination tables and chairs that facilitate easy access. For example, it is now desirable for a medical examination table or chair to be adjustable to a relatively low height to allow elderly patients, expectant mothers, or patients with disabilities to easily and efficiently access the table without the assistance of the attending medical personnel. Not only does a lowered table height decrease the patient&#39;s anxiety when accessing the table, but it also eliminates the stress and strain and potential injury to medical staff personnel who attempt to lift a patient onto a higher table. 
   However, when a medical examination table is lowered to a very low position, for example eighteen inches off the ground, while this height promotes access, it creates problems for the storage of a footrest section in the vertical position. In other words, when a table is lowered to such a low position, the hanging footrest will typically contact the floor. While an alternative to solve this problem is to decrease the size of the footrest, this is often not an acceptable alternative, as a shorter footrest section, when extended to its generally horizontal position for use, will be too short to accommodate the needs of the patient. 
   Accordingly, there is the need for a footrest section for a medical examination table that is capable of being stored in a generally vertical position when the table is positioned at its minimum height, yet also providing an adequate footrest section when positioned in the general horizontal position for use. Additionally, it is desirable for this function to be easily done whether the chair is being raised or lowered. 
   OBJECTS OF THE INVENTION 
   It is an object of the invention to provide a footrest section for a medical examination table whereby the table can be lowered to a minimum height with the footrest section stored in a generally horizontal position without contacting the floor, while providing an adequate footrest section when the footrest section is extended. It is also an objective of this invention to allow the transition of a footrest between its use and stored positions with minimal user interface. 
   SUMMARY OF THE INVENTION 
   The present invention provides an extendable and retractable foot section for a medical examination table whereby the footrest is adapted to extend when the footrest section is raised to its generally horizontal height for use, and alternatively, retract when the footrest section is lowered to its generally vertical position for storage. The coordinated movement of the footrest section is accomplished through the use of a linkage assembly, a slidable footrest section, and a table footrest support frame. Additionally, an actuator is provided to operably cause the linkage assembly to rotate the footrest support frame while simultaneously sliding the footrest. 
   The above and other objects and advantages of the present invention shall be made apparent from the accompanying drawings and the brief description thereof. 

   
     BRIEF DESCRIPTION OF THE DRAWINGS 
     The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate embodiments of the invention and, together with a general description of the invention given above and the detailed description of the embodiments given below, serve to explain the principles of the invention. 
       FIG. 1  is a perspective view of a medical examination table with an extendable and retractable footrest according to the principles of the present invention. 
       FIG. 2  is a perspective view of the extendable and retractable footrest, shown in  FIG. 1 , shown in its extended and generally horizontal use position. 
       FIG. 3A  is a side view partially in cross-section of the extendable and retractable footrest section shown in FIG.  2 . 
       FIG. 3B  is a side view partially in cross-section of the extendable and retractable footrest, shown in  FIGS. 2 and 3A , shown in the retracted and generally vertical stored position. 
       FIG. 4  is a top view partially broken away of the extendable and retractable footrest, shown in  FIGS. 2 ,  3 A, and  3 B, shown in the extended and generally horizontal use position. 
   

   DETAILED DESCRIPTION OF THE INVENTION 
   Referring to the figures, and to  FIG. 1  in particular, a medical examination table or chair  10  is shown in accordance with the principles of the present invention. The medical examination table  10  includes a footrest section  12 , a seat section  14 , and a back section  16 , and an optional headrest section  18 . The table  10  also includes a base  20  with a mechanical lift  22  which allows the seat section or the top of the table  14  to be lowered to a height at least as low as approximately 46 cm (18″) above the floor. Lowering the table  10  to such a height makes it easier for elderly patients, expectant mothers, or patients with certain disabilities to get on the table  10  without requiring the assistance of someone to lift them onto the table  10 . A table height of 46 cm (18″) not only allows patients to get on the table faster, easier, and safer with no or minimal staff assistance, it also minimizes patient anxiety and allows the patients to maintain their dignity. The lift section  22  of the table  10  is also adapted to raise the top of the table or seat section  14  to a height of at least as high as approximately 94 cm (37″). Alternative embodiments of the present invention could raise the table&#39;s  10  seat height  14  as high as approximately 102 cm (40″). By raising the table  10 , medical personnel do not have to do as much bending and stooping while attending to patients, thus minimizing their stress and strain. Thus the range of height options, from a low of about 46 cm (18″) to a high of about 102 cm (40″), allows for efficient and comfortable examinations by the medical personnel. Finally, while  FIG. 1  shows the back  16  of the table in a generally vertical position, this section, along with the headrest  18  and the footrest  12  can be positioned in a generally horizontal or other orientation, as needed, such as may be required for certain examinations. 
   As further shown in  FIG. 2 , the footrest  12  is comprised of a footrest pad or cushion  24 . Typically the footrest pad or cushion  24  will be comprised of an outer layer of upholstery such as vinyl or the like, with a foam or other cushioning interior core. In alternative embodiments, a rigid footrest pad  24  could be used. Such a footrest pad  24  could be comprised of plastic, metal, or any other suitable material. 
   The footrest pad or cushion  24  is mounted to a footrest plate  26  via a plurality of mounting receptacles  28 . Typically, the footrest pad or cushion  24  will be secured to the footrest plate  26  via bolts, screws, or other suitable fasteners (not shown) extending through the mounting receptacles  28 . The footrest plate  26  is attached to a pair of longitudinal generally rectangular shaped slides  30 ,  32  which are adapted to operatively slide longitudinally in a pair of spaced corresponding longitudinal channel  34 ,  36  attached to the housing  38  of the footrest support frame  40 . The footrest support frame  40  is further comprised of a pair of support brackets  42 ,  44  which are pivotally attached to the seat section  14  of the table  10  with pivotal connections  45 ,  47 . Support bars  42  and  44  are secured to the support frame  40  by way of weldments or fasteners. 
   The seat section  14  of the table is comprised of seat frame  46  and a seat pad or cushion  48 , which like the footrest pad and cushion  24  is typically comprised of an outer material such as vinyl with an inner foam or cushion core. In alternative embodiments, the seat pad or cushion  48  may be rigid and be comprised of plastic or metal. 
   As shown in  FIGS. 3A and 3B , the seat portion  14  of the table  10  may be connected to the back portion  16  of the table  10  by a bracket or linkage  50 . This bracket or linkage  50  can be adapted to allow the back portion  16  of the table  10  to rotate from a generally vertical position to a generally horizontal position. In addition, this bracket or linkage  50  can be used as a hinge whereby the entire seat portion  14  and back portion  16  of the table can be tilted or positioned as needed for procto or ob/gyn examinations. 
   As shown in  FIG. 2 , the seat frame  46  of the table  10  is comprised of a pair of parallel side walls  52 ,  54  which are connected to each other by a generally horizontal web portion  56 . Additionally, each of the side walls  52 ,  54  have a generally horizontal seat cushion plate  58 ,  60 , attached to them and upon which the seat pad or cushion  48  can be mounted. As shown, the footrest support bars  42 ,  44  are mounted to the respective side walls  52 ,  54  of the seat frame  46 . 
   Also mounted to the side walls  52 ,  54  of the seat frame  46  are a pair of linkage assemblies  62 ,  64 . These linkages  62 ,  64  are also attached to the side walls  52 ,  54  with pivotal connections  66 ,  68 , respectively (FIG.  4 ). The pivotal connections  45 ,  47 ,  66 ,  68  allow the footrest support bars  42 ,  44  and the linkage assemblies  62 ,  64  to rotate through approximately 90° of rotation from a generally horizontal orientation to a generally vertical orientation and vice versa. 
   The linkage assemblies  62 ,  64  are comprised of a pair of proximal links  70 ,  72 , a pair of medial links  74 ,  76 , and a pair of distal links  78 ,  80 , respectively (FIG.  4 ). The proximal links  70 ,  72  are pivotally connected to their respective side walls  52 ,  54  of the seat frame  46  with pivotal connections  66 ,  68 , and are also pivotally connected to their respective medial links  74 ,  76  with pivotal connections  86 ,  88 . The medial links  74 ,  76  are in turn pivotally connected to the distal links  78 ,  80  with pivotal connections  90 ,  92 . The distal links  78 ,  80  are pivotally connected to the slides  30 ,  32  of the footrest  12  with pivotal connections  94 ,  96 . The medial links  74 ,  76  are also pivotally connected to the footrest support frame  40  via a set of mounting link brackets  98 ,  100  and pivotal connections  102 ,  104 . Typically, each of the pivotal connections herein described are comprised of a bolt, washer, nut, or other like attachment component that provide for some degree of relative low friction, bidirectional rotation. 
   The linkage assembly or assemblies  62 ,  64  are designed to slide the footrest  12  out to its extended position while it is being raised to its generally horizontal or use position as is shown in  FIGS. 2 and 3A . Alternatively, the linkage assemblies  62 ,  64  are designed to retract the footrest  12  to its retracted position while it is being lowered to its generally vertical position, shown in  FIG. 3B , when not in use. The ability for the linkage assemblies  62 ,  64  to slide the footrest  12  to its extended position for use while the support brackets  42 ,  44  simultaneously rotate the footrest support frame  40  from its generally vertical stored position to its generally horizontal position for use, and reversing the process when the footrest  12  is no longer needed, allows the footrest  12  to be of a size so as to function as needed, while still providing for its vertical storage at a height lower than would normally be allowed due to the clearance from the floor. Accordingly, the table  10  can be positioned at a height much lower to the floor, than would otherwise be allowable with the typical footrest. 
   As also shown, an actuator  106  is attached to the footrest support frame  40  and pivotally attached to the floor or web portion  56  of the seat frame  46 . The actuator extender  108 , which may be a piston or screw, provides the displacement whereby the support brackets  42 ,  44  facilitate the raising or lowering of the footrest  12  and the linkage assemblies  62 ,  64  facilitate the extending or retracting of the footrest  12 . In an alternative embodiment (not shown) the actuator  106  could be located in the in the seat section  14  of the table  10  and could push on a linkage or bar that pivots and extends the footrest  12 . 
   As most clearly shown in  FIGS. 3A and 3B , the extender  108  is pivotally attached at  110  to the seat frame  46  at a position lower than the footrest support bars  42 ,  44  and the linkage assemblies  62 ,  64 . This placement further facilitates the desirable movement of the footrest  12 . 
   The actuator  106 , as shown, is powered by a motorized drive assembly  112 . Alternatively, the actuator  106  could be driven by a manual drive assembly (not shown). Additionally, the actuator  106  could be hydraulic, a screw, or a DC actuator. The operation of the actuator  106  is controlled by a limit switch  114  and the proximity contact  116 . 
   While the expandable and retractable footrest of the present invention has been illustrated and discussed in the context of a medical examination table or chair, it is not limited to those specific structures but could be used equally as well on other like structures such as a stool or other device wherein the extendable and retractable features of the present invention would be useful. Additionally, the present invention is not confined to use exclusively within medical applications, but may be used in other non-medical chairs or tables. 
   While the present invention has been illustrated by description of various embodiments and while these embodiments have been described in considerable detail, it is not the intention of the applicant to restrict or in any way limit the scope of the claims to such detail. Additional advantages and modifications will readily appear to those skilled in the art. The invention in its broader aspect is, therefore, not limited to the specific details, representative system, apparatus, and method, and illustrative example shown and described. Accordingly, departures may be made from such details without departing from the spirit or scope of the applicant&#39;s general inventive concept.