Abstract:
A patient self-assist transfer aid provides an open box frame having a base for fitting beneath a mattress of a bed, a riser section extending upwardly from the base for extending around an edge of the mattress and a positioning section for extending out over the mattress from the riser section. The open box frame may be positioned around the mattress end at the foot of the bed to leave the major sides of the bed open for ease of access. A linkage is fitted to the positioning section of the open box frame and may be extended therefrom to position a handle within easy grasp of a person laying in the bed. A spring system biases the linkage to a retracted position in the open box frame. A handle is pivotally attached to the linkage and for grasping by a patient recumbent in the bed or lowering him or herself into bed.

Description:
BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     The present invention relates to human mobility aids, and more particularly to an aid to be used by a person in moving from a fully reclined position in bed to a standing position adjacent the bed and back. 
     2. Description of the Art and Problem 
     Even a brief review of the art reveals numerous references which provide systems for helping patients get into and out of bed without caregiver assistance. Many of the references teach bed rail and handle systems, adapted by positioning and shaping, to give support to a person moving from a sitting position on a bed to a standing position adjacent the bed, or from a standing position back to a sitting position. Indeed, for many infirm individuals, moving from a sitting to a standing position is the greatest challenge and such devices are very useful for maintaining balance as they stand. However, the problems involved in getting into and out bed frequently involve more than moving from standing to sitting or from sitting to standing. Some references implicitly recognize that helping the patient stand up from, or sit down on, a bed or chair is just one part of the problem, for example U.S. Pat. No. 3,739,793 to Wilson. 
     Some conditions, such as Parkinson&#39;s disease, can contribute to a progressive degeneration of the abdominal muscles, which makes sitting up without assistance difficult or impossible. Temporary conditions, such as recovery from abdominal surgery can also leave the abdomen weak. Relatively few references deal with bed ingress and egress assistance devices which provide assistance to individuals in sitting up in bed. One reference that does teach such a device is U.S. Pat. No. 4,679,265 to Wicks. Wicks teaches a tether hooked to an anchoring member, which is provided by a U-shaped hook sized to be fitted around the foot of a bed mattress. Using the tether a person can help themselves sit up from a recumbent position by pulling themselves up on the tether. While the device is exceedingly simple and unobtrusive, it is unclear how the tether remains positioned for easy grasping by the bed occupant over the course of a night. Nor does the system do anything for individuals who have lost substantial upper body strength. A trapeze system is taught in U.S. Pat. No. 4,686,727 to Wilkinson, which provides assistance to patients in sitting up from bed. Another such system is that taught in U.S. Pat. No. 4,253,207 to Marcyan. In trapeze systems a bar or handle is suspended over the bed for grasping by the bed occupant. 
     A common theme among several references is ease of installation and portability, which is carried out in part by tubular construction of rail systems and extensions of the tubing to fit under and to be anchored by the bed&#39;s mattress. U.S. Pat. No. 5,471,689 to Shaw is a good example of a device incorporating these features. 
     SUMMARY OF THE INVENTION 
     An object of the invention is to provide an apparatus aiding the infirm in getting into and out of bed by helping the person move from a standing position adjacent the bed to a recumbent position on the bed and back. 
     Another object of the invention is to provide a patient mobility aid for use with beds which does not limit access to the bed. 
     It is a still further object of the invention to provide an aid for use with beds which is readily removed or placed in the bed. 
     According to the invention there is provided a patient self-assist transfer aid for use with a bed. The self-assist transfer aid comprises an open box frame having a base for fitting beneath a mattress of a bed, a riser section extending upwardly from the base around an outside edge of the mattress and a positioning section for extending out over the mattress from the riser section. The open box frame may be positioned around the mattress end at the foot of the bed to leave the major sides of the bed open for ease of access. A linkage is fitted to the positioning section of the open box frame and may be extended therefrom to position a handle within easy grasp of a person lying in the bed or laying down on the bed. A spring system biases the linkage to a retracted position in the open box frame. A handle is pivotally attached to the linkage and for grasping by a patient lying in the bed or lowering him or herself into bed. 
     Additional effects, features and advantages will be apparent in the written description that follows. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     The novel features believed characteristic of the invention are set forth in the appended claims. The invention itself however, as well as a preferred mode of use, further objects and advantages thereof, will best be understood by reference to the following detailed description of an illustrative embodiment when read in conjunction with the accompanying drawings, wherein: 
     FIG. 1 is a perspective view of a preferred embodiment of the self-assist mobility aid of the invention; 
     FIG. 2 is a side elevation view of the embodiment of FIG.  1 . 
     FIG. 3 is a top plan view of the embodiment. 
     FIG. 4 is a cross sectional view of an extensible piston rod used in the first embodiment. 
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
     Referring now to FIGS. 1 and 2, a preferred embodiment of the transfer aid  10  of the present invention is illustrated. Transfer aid  10  comprises a frame  11  which is shaped to provide a base which fits between a mattress  16  and a foundation  18  such as box springs or a bed platform. From its base the frame extends around an edge of the mattress  16 , preferably the end of the mattress located at the foot of a bed. The opposite end of frame  11  is located over the mattress. On the end of frame  11  over mattress  16 , a handle  12  and a support brace  14  are positioned for the use of a person getting into and out of bed. 
     The upper section of frame  11 , defined in part by arms  23  and  27 , slants downwardly from a location over the end of the mattress  16  toward the head of the bed. Handle  12  is movable on frame  11  from the end of the frame over the bed in the directions indicated by double arrow “A”. Handle  12  thus may be extended somewhat downwardly toward the head of the bed and retracted back into frame  11 . Handle  12  is spring loaded to urge the handle toward a retracted position within frame  11 . Spring tension is preferably selected to provide almost all of the retractive force required to pull a recumbent individual to a sitting position. Thus a person can use handle  12  to gently lower themselves onto the bed from a sitting position and can, from a recumbent position, pull the handle towards themselves. Handle  12  is also rotatable in the directions indicated by double arrow “B” on an axis which is parallel to the upper major surface of mattress  16  to allow the handle to be pushed out of the way. 
     A support brace  14  is also mounted to a cross member  34  near the upper end of frame  11 . Support brace  14  may be rotated in the directions indicated by double arrow “C” about an axis substantially perpendicular to the upper major surface of mattress  16 . Brace  14  may be moved out over one of the major edges of mattress  16  to provide support to a person moving from a standing position along side the bed to a sitting position on mattress  16 , or from a sitting position on the mattress to standing alongside the bed. 
     Frame  11  has three major sections, defined by their respective functions, which are as a base or foundation to support aid  10  in standing on one side of the frame, to position patient aid braces and handles within easy reach for use in moving from position to position, and to provide support to the positioning section from around an edge of a mattress for a bed. Frame  11  is constructed from two tubular members  20  and  24 , and a plurality of transverse cross members  28 ,  30 ,  32  and  34 . Each tubular member has, in turn, three major sections corresponding to the principal parts of the frame  11 . For tubular member  20  there is a base leg  21 , an upright  22  and a positioning arm  23 . The tubular member  20  may be formed from a single tube with curved transition sections between the major sections. Similarly, tubular member  24  has a base leg  25 , an upright  26  and a positioning arm  27 . The base of frame  11  is defined by a base legs  21  and  25  and a lower cross member  28 . The base is illustrated as positioned below a mattress  16 , which stabilizes frame  11  on a box spring or platform  18 . 
     Vertical support for arms  23  and  27  is provided by vertical uprights  20  and  24 , respectively. Uprights  20  and  24  are braced against on one another be cross member  30 . Positioning arms  23  and  27  are linked by cross members  32  and  34 . Cross members  28 ,  30 ,  32  and  34  are attached to tubular members  20  and  24  by suitable fastening means. For cross members  28 ,  30  and  32  these may include penetration of the tubular members  20  and  24  by the ends of the cross members coupled with screws through the bodies of the tubular members into the cross members. Cross member  34  serves other functions and is attached to tubular members  20  and  24  somewhat differently as is described below. Frame  11  generally defines a U-shaped frame, which can be fitted around one edge of bed mattress and which is held in place by the mattress. 
     Specific construction elements, such as tubular frames, joints, bends and cross members, including consideration of their size and material may vary upon specific application of the device, for example in houses or health care facilities, or the type of bed used. Spring types, fasteners and the like may be chosen based on cost considerations or the desire for the highest refinement of the tool. The basic design concept would be unchanged. For example, hospital and nursing home beds are different than beds normally found in individual houses or apartments in that a spring grid is all that is provided immediately under the top level bedding element. No box spring is provided and as a result no integral surface exists as a base. In such an application a tubular frame base would not be appropriate. In some applications a welded joint in place of a solid bent joint, or rectangular tubing instead of circular cross-section tubing, may enhance rigidity. Exterior mounted adjustable gas springs could be substituted for internally mounted metal compression springs could be used. 
     FIG. 2 is a side elevation of frame  11  illustrating more fully tubular member  20  and the position and movement relative thereto of handle  12 . Brace  14  swings on a pivot axis  70  which is perpendicular to the upper major surface of mattress  16 . A plurality of screws  80  are set in tubular member  20  to hold cross members in place. Similar screws (not shown) join the cross members to tubular member  24 . 
     Referring now to FIGS. 3 and 4, the mechanical features of the preferred embodiment supporting the positioning and the use of handle  12  and brace  14  are illustrated. Handle  12  is mounted on co-axial pivoting mounts  42  and  44 , which are provided by rods  50  and  52  to position a gripping section  36  within easy reach of a person laying in a bed. Rods  50  and  52  are mounted for rotation in cylinders  46  and  48  with rod exerts  54  and  56  extending from the cylinders to mate with holes through handle arms  38  and  40 , respectively. Appropriate threaded nuts or other fastening elements may be used to hold handle  12  on rod exerts  54  and  56 . 
     Extension and retraction of handle  12  relative to frame  11  is supported on piston rods  62  and  64 , which extend from the bases of mounting cylinders  46  and  48 , respectively, and which are partially inserted into the open ends of positioning arms  23  and  27 . Rods  62  and  64  are free to move in and out of positioning arms  23  and  27  except as restrained by retaining nuts  67  and  69 , which are attached to the inserted ends of the rods, and by restraining caps  78  and  80 . Restraining caps  78  and  80  close the open ends of positioning arms  23  and  27  save for annular openings sized to pass rods  62  and  64 . Restraining caps  78  and  80  are of smaller diameter than the width of nuts  67  and  69  and block the passage of springs  66  and  68 . This allows the free traversal of the rods  62  and  64 , while providing a base against which compression springs  66  and  68  impinge when forced by nuts  67  and  69 . 
     Compression springs  66  and  68  urge rods  62  and  64  to retracted positions in positioning arms  23  and  27  by pressing against nuts  67  and  69  from restraining caps  78  and  80 . Springs  66  and  68  are positioned within arms  23  and  27  and are held in place by retaining nuts  67  and  69 , affixed to the inserted ends of rods  62  and  64  and restraining caps  78  and  80 . If desired, the tension on compression springs  66  and  68  may be adjusted for heavier individuals by inserting tensioning inserts  74  and  76  between the ends of the springs and either the retaining nuts  67  and  69 , respectively, or between the springs and the restraining caps  78  and  80  (not shown). Alternatively, an end portion of the piston rods  62  and  64  may be threaded and threaded fasteners such as nuts placed thereon. The fasteners then provide bases for an end of each tensioning spring and can be positioned to adjust spring tension. Sprig  66  and  68  and tensioning inserts  74  and  76  are selected to allow adjustment of the retractive force on handle  12  to be adjusted for the weight or strength of the person who will use the device. For a patient with minimal upper body strength and no abdominal strength, the maximum retractive force, exerted when handle  12  is pulled to the required extension to reach the patient in a prone condition, should fall just short of matching the fully reclined patient&#39;s weight on the handle. The patient then should have to do little more than pull him or herself up a few centimeters on the handle  12 , reducing the effective weight on the handle to allow spring tension to pull the individual to an upright sitting position as soon as spring force exceeds the patient&#39;s applied weight. An electric motor could also be utilized for retracting the handle  12 . 
     Brace  14  is pivotally mounted to an extension of cross member  34 , which positions the pivot  70  for the brace at a point horizontally displaced from the upper or positioning section of frame  11  toward an edge of the bed. A pivot stop  72  limits travel of brace  14  toward the center of the bed and allows the infirm user of the apparatus to pull him or herself around to bring their legs over the edge of the bed. Brace  14  may then be pivoted outwardly over the edge of the bed, or to other convenient positions, to provide a support for the individual as he or she stands. It should be apparent that brace  14  and handle  12  may be used to reverse the process as well. 
     The present invention aids the infirm in getting into and out of bed, generally without assistance of another individual, or in the case where two elderly persons live together, eases the task of getting a mate out of bed. The preferred embodiment is readily installed on most beds, requiring no permanent physical modification of the bed, and is readily removed if desired. When positioned with a bed the apparatus does not limit access to the bed by blocking the major sides with rails. 
     While the invention is shown in only one of its forms, it is not thus limited but is susceptible to various changes and modifications without departing from the spirit and scope of the invention.