Abstract:
A patient assistance and rehabilitation device or more specifically a patient mechanical lift device that can be utilized as patient walker, a seat, a seated transporter, a toilet, a table and a rehabilitation device. The patient assistance and rehabilitation device including a power band or tension motor to help a patient move from a sitting to a standing position and to supplement an exercise or rehabilitation program.

Description:
BACKGROUND OF THE INVENTION 
     The present invention relates generally to patient assistance and rehabilitation device or more specifically a patient mechanical lift device that can be utilized as patient walker, a seat, a seated transporter, a toilet, a table and a rehabilitation device. 
     Caring for the aging, incapacitated or invalid persons is a problem inherent with being human, and as we continue to improve medicine and health care, people are living significantly longer, thus creating a greater need for caretakers and a support structure for people having diminished physical capacity. However, it is also human nature to desire to be independent and take care of one&#39;s own personal needs whenever possible. For a person with diminished physical capacity, performing simple tasks such as, getting out of bed, travelling across a room, exercising and getting to the restroom may become milestones, or acts of great achievement, that will validate that person and fill them with strong sense of accomplishment and self-worth. 
     Due to the universal nature of the problem, there are myriad devices designed to help people having diminished physical capacity, this includes, wheeled furniture that has been in use for centuries, to walker/lift devices that have developed in recent years. The more recent devices include an INVALID LIFT AND TRANSFER DEVICE, U.S. Pat. No. 3,277,502, filed Sep. 25, 1964 to Wauthier or the PATIENT ASSIST DEVICE, U.S. Pat. No. 4,985,947, filed May 14, 1990, to Ethridge. Each of these devices have features that may help a person having diminished physical capacity but each of these devices also has limitations; the device of Wauthier can be used to raise a person into a standing position but only with the assistance of a second person pushing down on a mechanical lever positioned on the side of the device opposite the patient. Whereas, the device of Ethridge will allow a patient with diminished physical capacity to rise to a standing position on their own, however, this is only accomplished using a complicated cable and pulley assembly powered by an electric motor. 
     What is needed is a device having a simple mechanism which will allow a person having diminished physical capacity to rise into a standing position without necessarily requiring an assistant and the device providing additional functionality that will help accommodate the user throughout the day. 
     SUMMARY OF THE INVENTION 
     The present invention is a patient assistance and rehabilitation device, or more specifically a patient lift and transfer device having mechanical assistance which will allow a person or patient with minimally diminished capacity to move from a seated position at the edge of a bed, chair or similar device to a standing position with the aid of the patient lift and then use the lift as a walker. In the case of a more fully diminished patient, the lift is configured to allow an assistant to provide additional stabilization and lifting using an adjustable lift handle; the lift can include a sling seat, a split hard seat, a split toilet seat and a table top accessory. 
     A first embodiment of the present invention includes a rolling base assembly formed generally in a U-shape, the open side facing toward the rear of the device. A pair of adjustable upright members that extend vertically from each side of the rolling base assembly. A patient lift table assembly also formed generally in a U-shape is attached to the top of the upright members. The open portions of the U-shaped configuration of the rolling base assembly and the lift table assembly facing toward the rear of the device, allowing a patient to easily access the lift device. The adjustable upright members connect to the rolling base assembly toward the closed front of the lift in a foldable configuration. Attaching the upright members toward the front of the device allows the rolling base assembly to be moved at least partially under a bed or furniture and places a seated patient seated in a better position within the device to make the transition from seated to standing. The foldable configuration of the upright members allows the device to be collapsed to a reduced size for shipping or storage. The patient lift table is connected to the upright members toward the open portion of the U-shape in a pivotal configuration, or in a configuration where the patient lift table is allowed to pivot in a “sea-saw” motion front to rear. The connection point is configured to take advantage of the principal of a simple lever and fulcrum and multiply the force applied to the front of the patient lift table at the rear of the patient lift table. In one embodiment the force/lever ratio is 2:1, in other embodiments the ratio is 1.5:1, 2.5:1, 3:1 or 3.5:1 or another appropriate ratio, in yet another embodiment the force/lever ratio is variable. Patient handles are attached to the lift table forward of the pivot point, or fulcrum, opposite from the patient&#39;s body and allows the patient to lean into the device and apply pressure to the handles and create lift under elbows, upper arms and to the thighs through a seat assembly. This force is augmented by a tension motor or plurality of elastomeric power bands that are tensioned between the front of the rolling base assembly and the patient lift table assembly, the power bands biasing the front of the lift table down and applying additional force to help lift the patient. 
     In one embodiment of the present invention the patient assistance and rehabilitation device includes an incremental locking assembly or D-plate assembly at the junction between the upright members and the patient lift table. The D-plate assembly is configured to allow the patient lift table to move or pivot a certain number of degrees and then lock the patient lift table from moving back in the opposite direction. This function allows a patient to move the lift table, with assistance from the power bands, and then essentially rest, holding onto the patient handles or leaning into arm pads configured to receive the patient&#39;s forearms. When the patient is prepared, the patient can rock forward to add force to the handles and the lift table to move the D-plate assembly into the next incremental stop. This process can be repeated until the patient is in a standing upright position with the lift table tilting forward and functioning like supported crutches or the patient is seated and the patient lift table is substantially level. 
     The D-plate assembly is configured as a set of the three inter-locked plates having a central pivot, the innermost plate includes a direction handle, and a plurality of recesses formed around the lower perimeter, the central plate essentially mirrors the innermost plate, minus the handle, and acts as washer or slip plate between the innermost plate and the outermost plate. The central plate includes a plurality of elongate holes having a center point that matches the center point of the recesses formed in the perimeter of the innermost plate. The outermost plate includes a plurality of elongated holes or slots also having a center-point corresponding with the center point of the recesses formed in the innermost plate, the elongated holes have a chamfer or bevel on the outside surface. A spring-loaded locking plunger rod assembly is attached to the upright member and is configured to interface with the elongated slots and holes in the D-plate assembly. The plunger rod is chamfered on the outside end surface. The outermost plate also includes a plurality of limit slots formed in a radius between the elongate holes and the pivot point, each of the central slip plate and the inner-most plate have holes that correspond to the center point of the limit slots formed in the outer-most plate. A plurality of bolts and sleeve nuts are configured to pass through all three plates. With the bolt and sleeve nuts in place, the innermost plate and the central slip plate are aligned in a similar orientation with holes of the central plate concentric with the recesses of the innermost plate. The bolts and sleeve nuts restrict the movement of the outmost plate to the length of the limit slots. The length of the limit slots translate into angular movement of the outermost plate of between 5 and 10 degrees. When the direction handle of the inner-most plate is moved toward the front of the patient lift, the recesses of the innermost plate align with the back radius of elongate slots of the outermost plate and the outmost plate will engage the shaft of the plunger rod and restrict the lift table from rotating down on the patient side of the upright members. However, in this configuration a ramp is formed where the chamfered end of the plunger can ride up out of the recesses of the innermost plate, over the central glide plate and out of the chamfered edge of the elongate slot of the outermost plate and then incrementally drop into the next slot when downward pressure is applied to the front of the patient lift table. When the direction handle is moved in the opposite direction, or pulled back toward the patient, the patient lift table is restricted from pivoting up on the patient side of the upright members. In one embodiment a detent ball spring assembly is used to bias the D-plate assembly in the forward and backward position. If a user desires to lock the patient lift table in a fixed position, the D-plate assembly direction handles can be moved into opposing positions or where one side is moved forward and the other side is moved into the backward position. 
     In another embodiment, the plunger assembly rod is lockable in a retracted or open position which allows free rotational movement between the lift table and upright members. In this configuration the patient can use their arms or legs to exercise by pushing with their legs or pulling on the patient handles and moving the patient lift table against the pressure of the power bands. It is contemplated power bands may be added or removed from the front of the patient lift table to vary resistance during exercise. In one exercise the patient may plant their feet firmly on the floor and squat down using body weight against the tension of the power bands, the patient can hold this position in a “stabilized” squat and then rise up into a full standing position using the assistance of the power bands. One seated exercise allows a patient to place their feet on the front rolling frame cross bar and then pull back on the patient handles and rock back against the power band tension. This position may also be used to focus more fully on using the abdominal muscles or core to bend at the waist toward the front of the patient lift table and then focus the core to move back against the pressure of the power bands. It is contemplated that a multitude of different focused exercises may be developed using only the patient assistance and rehabilitation device or additional accessories such as yoga blocks or stretch bands. 
     In one embodiment of the present invention or patient assistance and rehabilitation device the power bands extend from front portion of the patient lift table down to a releasable rack or cross bar that is pivotally attached to the front cross brace of the rolling base assembly. The releasable rack allows an assistant to add or remove a plurality of power bands without being exposed to the full tension of the band and the attachment hardware which minimizes the risk of accidentally releasing a band before it is securely attached and having the elastomeric band retract and strike either the patient or assistant. After the desired number of power bands are attached to the releasable rack, the assistant can depress the rack using their foot to engage the power bands and engage a mechanism that locks the releasable rack against the front portion of the rolling base assembly. In one embodiment the releasable lock mechanism is disengaged in a two-step process of depressing the rack with one foot and using a lever on the patient lift table to disengage a latch mechanism. Once the latch mechanism is released the user can lift their foot to slowly disengage the pressure on the power bands. 
     In another embodiment of the present invention or patient assistance and rehabilitation device a supplemental lift handle is attached to the front portion of the patient lift table. The supplemental lift handle extends away from the lift table to allow an assistant to provide additional lifting force when moving a patient into a standing position. In one embodiment the supplemental lift handle can be rotated and locked in a variety of positions. The lift handle including a releasable locking cog that is configured to engage a plurality of the slots arranged in a radial pattern that is concentric with the front cross-bar portion of the patient lift table. The supplemental lift handle can be moved into a position facing the patient and may be used by the patient as an alternate grab bar or hand rest. Or it may be released and locked into an upright position which allows an assistant to pull, rather push down on the handle, when providing additional force to lift a patient into a standing position. The supplemental lift handle provides the greatest force moment when the handle is in a position facing away from the patient and in the same plane as the patient lift table. 
     One embodiment of the present invention includes a sling seat that is attached to the rear portion of the patient lift table and can be used to support a patient during transit or to allow the patient to remain in the device in a comfortable seated position. It is contemplated that the sling is placed under a patient&#39;s thighs while the patient is in a seated position near the edge of a bed or chair. Once the sling seat is under the patient, a padded front support strap is pulled up through the patient&#39;s thighs and the seat and padded front support strap are connected to the lift table using seat attachment knobs. In another embodiment a back brace or support is additionally attached to the lift table and is configured to engage the patient&#39;s lower back and provide additional support and overall comfort. 
     In one embodiment of the present invention a conventional seat may be added in lieu of the sling seat. The conventional seat is configured as two interlocking halves which are attached in a pinned swinging configuration to the upright support members. When a user is standing with the assistance of the lift table the conventional seat halves can be swung in under the patient and locked into a fixed position. The conventional seat is configured for maximum comfort when a patient chooses to spend extended periods of time in the patient assistance and rehabilitation device. 
     In another embodiment of the present invention includes a toilet seat with a waste pan that can be placed under the patient and allow the patient to sit while eliminating waste. In one embodiment the toilet seat is one piece which swings in under the patient and mates with a secondary support that is attached to the opposing upright support member. In another embodiment the toilet seat is a split seat divided approximately equally in half, as such, each half is attached to support bracket which is pivotally pinned to the upright support members. In each embodiment a waste collection pan is configured to attach under the toilet seat. An assistant can readily remove the pan for waste disposal and cleaning. 
     In one embodiment of the present invention a work surface or table is configured to be releaseably attached to the top of the patient lift table portion. The table top may substantially be a rectangular shape that covers the front portion of the lift table or the table top may include extensions or wings that wrap back around the side of the patient. The table top may be configured to include such accessories as a storage compartment, cup holder, recessed pockets for small items, spill lips or a ridge to prevent round objects from rolling off of the table top. 
     In one embodiment the patient assistance and rehabilitation device will include an adjustable height mechanism at the upright support members, extendable length for the rear tubes of the patient lift table, forward extension of the patient lift table, and accessories such as brakes configured to lock at least one wheel on the rolling base. 
     These and other features and advantages of the disclosure will be set forth and will become more fully apparent in the detailed description that follows and in the appended claims. The features and advantages may be realized and obtained by the instruments and combinations particularly pointed out in the appended claims. Furthermore, the features and advantages of the disclosure may be learned by the practice of the methods or will be obvious from the description, as set forth hereinafter. 
    
    
     
       BRIEF DESCRIPTION OF DRAWINGS 
       The following description of the embodiments can be understood in light of the Figures, which illustrate specific aspects of the embodiments and are part of the specification. Together with the following description, the Figures demonstrate and explain the principles of the embodiments. In the Figures the physical dimensions of the embodiment may be exaggerated for clarity. The same reference numerals in different drawings represent the same element, and thus their descriptions may be omitted. 
         FIG. 1  illustrates one embodiment of the present invention or patient assistance and rehabilitation device with a seated patient; 
         FIG. 2  illustrates a side view of one embodiment of the present invention or patient assistance and rehabilitation device; 
         FIG. 3  illustrates a front view of one embodiment of the present invention or patient assistance and rehabilitation device; 
         FIG. 4  illustrates a perspective view of one embodiment of the present invention or patient assistance and rehabilitation device; 
         FIGS. 5A and 5B  illustrate a table top and a side view of one embodiment of the present invention or patient assistance and rehabilitation device; 
         FIG. 6  illustrates a locking D-plate assembly; 
         FIG. 7  illustrates an exploded view of a locking D-plate assembly; 
         FIG. 8  illustrates a front view of a locking D-plate assembly in a forward locked position; 
         FIG. 9  illustrates a sling seat and backrest assembly; 
         FIG. 10A  illustrates a toilet assist sling seat in a first position, and; 
         FIG. 10B  illustrates a toilet assist sling seat in a second position. 
     
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
     For the purposes of promoting an understanding of the principles in accordance with the disclosure, reference will be made to the embodiments illustrated in the drawings and specific language will be used to describe the same. It will nevertheless be understood that no limitation of the scope of the disclosure is thereby intended. Any alterations and further modifications of the inventive features illustrated herein, and any additional applications of the principles of the disclosure as illustrated herein, which would normally occur to one skilled in the relevant art and having possession of this disclosure, are to be considered within the scope of the disclosure. 
     As used in this specification and the appended claims, the singular forms “a,” “an,” and “the” include plural referents unless the context clearly dictates otherwise. In describing and claiming the present disclosure, the following terminology will be used in accordance with definitions set out below. As used herein, the terms “comprising,” “including,” “containing,” “characterized by,” and the grammatical equivalents thereof are inclusive or open-ended terms that do not exclude additional, unrecited elements or method processes. 
     Illustrated in  FIGS. 1 through 6  is of one embodiment of the present invention or patient assistance and rehabilitation device  100 , some of the figures include a seated patient  500 . Patient assistance and rehabilitation device  100  includes as major components, the rolling base assembly  110 , upright support members  120  and the patient lift table  130 . The rolling base assembly  110  is generally a U-shaped frame assembly having two base side rails  114  and a front cross brace  115 ; the rear rolling base assembly  110  is open to allow patient access and to allow the patient to stride or move their feet. The rolling base assembly includes a rear caster  111 , a central wheel  112  and front caster  113 . In this configuration the patient assistance and rehabilitation device  100  is a stable platform that can be easily turned and maneuvered, when a side pressure or rotational force is applied, both the rear caster  111  and front caster  113  will move into a trailing position perpendicular to the central wheel  112  and allow the device  100  to pivot or turn in a radius approximately the same as the wheel base between the opposing central wheels  112 . In one embodiment of the present invention a brake assembly (not shown) is configured to engage at least one of the central wheels  112 . It is contemplated that the brake is biased into a closed or locked position where the user must first engage a hand lever  133  before the patient assistance device  100  can be moved. 
     Upright support members  120  are pivotally connected to the rolling base assembly  110  having a locking pin  123  to maintain support members  120  in an upright position. The patient lift table assembly  130  it pivotally attached to the upper end of the upright support members  120 . The upright support members  120  are also extendable to adjust the patient lift table height; this is accomplished by releasing the height locking pin  122  and extending an inner support tube  121 , the inner support tube  121  having a plurality of the height adjustment holes (not shown) configured to engage the shaft of height locking pin  122 . The attachment point between the upright support members  120  and patient lift table  130  includes a releasable incremental locking mechanism or a D-plate assembly  150 . Additionally, the attachment point between the upright support members  120  and patient lift table  130  creates a fulcrum  139  and is configured to multiply force that is applied to the front portion of the lift table  130  and patient handles  132 , using the principle of simple levers, to the back portion of the lift table  130  and use that force to help a patient move from a seated to a standing position by supporting and lifting the patient by the forearms and thighs. The pressure to the forearms is evenly distributed by armrest pads  134 , the patient may also steady themselves using the patient handles  132 . The D-plate assembly  150  allows a patient to incrementally move into a standing position, as the patient raises, the D-plate will index forward and lock backwards against pivot pin assembly  151 . The D-plate  150  indexing mechanism allows the patient to rest in a partially standing position and prevents the patient from falling back fully to the original seated position. 
     If a patient has further diminished physical capacity additional force from a one or more power bands  170  that extend from essentially the front cross bar  115  to the patient lift table cross bar  131 , can be used. The power bands apply additional downward force against the front portion of the lift table  130  to help a patient move into a standing position. In one embodiment, the power bands  170  are connected to the rolling base  110  using a releasable power band rack  175 , the power band rack  175  is configured to remove the tension from the power bands  170 , to preserve the elasticity of the bands  170 , to provide easier installation of individual power bands  170  on connection loops  171  and reduce the risk associated with tensioned elastic materials. Rack  175  is configured to be released by having an assistant first depress the top portion of rack  175  with a foot to relieve pressure from locking mechanism  176  and then pulling lever or handle (not shown) located on top of the patient lift table to disengage the latch mechanism  176  from cross bar  115 . 
     In one embodiment of the present invention a supplemental lift handle  140  is provided, the supplemental lift handle  140  includes a lift assistance handle  141  which is attached to the lift table cross bar  131  with a ratchet assembly  143 . The ratchet assembly  143  is comprised of a metal ring having a plurality of the radial slots that is attached concentric with the lift table cross bar  131  and is engaged in by a dog or pawl that is actuated by a spring biased release knob  142 . When knob  142  is pulled, the patient lift assistance handle  141  can be moved incrementally in relationship to the patient lift table cross bar  131 . When handle  141  is extended away from the lift table  130  in a plane parallel to the lift table  130  an assistant is afforded the maximum leverage when lifting a patient by pushing down on handle  141 . An assistant or aide may choose a variety of angles or positions for the patient lift assistance handle  141  depending on the size of the assistant, the perceived comfort of using each position, and the amount force necessary to lift the patient. 
     In another embodiment of the present invention the patient lift table  130  is extendable both at the front and in the rear. If a larger patient or a patient with longer arms is using the device, the front portion of the lift table  130  can be extended by releasing lock pin  135  and extending out an inner patient lift table tube section  1301 . The rear portion of the lift table can be extended by releasing a similar knob and extending the rear patient lift table inner tube sections  1361 . 
     Another embodiment of the present invention or patient assistance and rehabilitation device  100  a plurality of other assemblies or accessories which allows a patient to sit are included. In a first embodiment a sling seat  183  and backrest  182  is included as shown in detail  FIG. 9 . The sling seat is attached to the seat attachment knobs  136  at attachment loops  1836  and the sling seat  183  can be extended under the patient while the patient is in a sitting position on the edge or a bed or chair and used to raise the patient into a sitting or standing position within the patient assistance and rehabilitation device  100 . A padded front support strap  1831  can be pulled between the patients legs and secured to attachment knobs  136  at front strap attachment loops  1834 . The front support strap  1831  in combination with a padded connection support  1832  secures the patient in sling seat  183  and prevents the patient from sliding or slumping forward. Spreader rods  1835  are incorporated to prevent the fabric or material of sling seat  183  from bunching and to keep the sling seat  183  in a flat configuration. In another embodiment an additional back support strap  182  with back strap connection loops  1821  is provided to give the patient additional back support when remaining seated in the device for an extended period of time. 
     In yet another embodiment a toilet seat  181  can be provided to allow a diminished patient to eliminate waste without getting out of the device  100 . The toilet seat  181  can be fitted with a removable waste pan  185 . It is also contemplated that the toilet seat  181  can be used in accompaniment with a secondary toilet sling seat  192  as shown in  FIGS. 10A and 10B . The toilet sling seat  192  is configured to be placed under a patient&#39;s thighs and suspended from attachment knobs  136  using the toilet sling seat attachment loops  1933 . The leg straps  1931  are wrapped around the inside of patent&#39;s thighs (see folded sling strap  1931  in  FIG. 10B ) before they are also connected to knobs  136  at one of a plurality of connection slots  1932 . The toilet sling  192  is beneficial when moving a patient onto the toilet seat  181  and positioning the patient&#39;s thighs in an open position for cleaning and patient hygiene. 
     In another embodiment, a split conventional seat is provided (not shown), the conventional seat may be attached to seat support brackets  180  which rotate on hinge pins  186 . 
     In another embodiment of the present invention a table top  138  ( FIG. 5A ) can be fitted to the patient lift table  130 . 
       FIGS. 6, 7 and 8  illustrate an embodiment of the locking and indexing assembly for the patient lift table  130  or more specifically an embodiment of the D-plate assembly  150 . The D-plate assembly  150  is primarily comprised of the three interacting plates with each plate having substantially the same semi-circular shape or profile and each plate rotates around a central axis having a pivot hole  1512  configured to receive the shaft of a connecting pin or bolt that joins the upright support members  120  and patient lift table  130 . The innermost plate  152  comprises a semi-circular shape having a lock control handle  1525  extending perpendicular to one edge. The innermost plate  152  includes a plurality of index recesses  1553  formed on the inside surface proximate the outer edge of the semicircular portion. The central plate  153  is formed using a material such as nylon or high density polyethylene to primarily provide a slip plane between the innermost plate  152  and the outermost plate  154 . The central plate  153  includes a plurality of elongated index holes  1552  having a center point which correspond to the index recesses  1553  of the innermost plate  152 . The outermost plate includes a plurality of elongated index holes  155  which again correspond to the recesses  1553  of the innermost plate. The index holes  155  of the outermost plate  154  include a chamfered outside edge  156 . The outermost plate also includes a plurality rotation limit slots  1571  which are formed in an arc between the pivot hole  1512  and the elongated index holes  155 . Each of the innermost plate and the central plate having drilled holes  1572  and  1573  that correspond with the limit slots  1571 . Also included between plates is a centering spring and ball detent  159  configured to bias toward or indicate the forward and backward positions of the indexed plates. When assembled the innermost plate  152  will have the central slip plate  153  stacked on and then the outermost plate  154  and then a plurality of sleeve bolts  157  that extend through the limit slots  1571  and the drilled holes  1572  and  1573 . As shown in  FIG. 8  when the handle  1525  is pulled back, this causes the innermost plate  152  and the central plate  153  to move a limited number of degrees in relationship to the outermost plate  154  in this position the front portion of the elongate holes  155  will form a shoulder that retains the spring loaded plunger rod  158  of the plunger assembly  151 . However, rear portion will create a ramp that allows a chamfered end of the plunger rod  158  to ride up out of the recess  1153 , over central plate  153  and out of the elongated slot  155  and then fall into the next corresponding elongated slot  155 . This operation is reversed if handle  1525  is pushed forward away from the patient and moves the blocking shoulder to the back portion of the elongate holes  155 . Plunger assembly  151  includes a locked open position that allows the patient lift table to rock or “sea saw” back and forth unrestricted.