Abstract:
The lift of the present invention includes a lightweight, foldable lift that can be conveniently transported and stored in a home or car. According to a first preferred embodiment, the lift of the present invention may be operated as a caregiver lift to allow a typical caregiver to handle a patient under a wider variety of conditions and circumstances than the industrial sized lifts of the prior art. Further, the lift of the present invention is designed to allow a patient to be moved in all directions and to operate on a variety of surfaces.

Description:
RELATED APPLICATIONS 
       [0001]    The present invention claims priority to U.S. Provisional Application No. 62/059,589 filed Oct. 3, 2014. 
     
    
     FIELD OF INVENTION 
       [0002]    The present invention relates generally to a lifting mechanism and, in particular, to a light weight foldable lifting mechanism designed to aid an operator in lifting a load under a wide variety of settings and circumstances. 
       BACKGROUND OF THE INVENTION 
       [0003]    Generally, a patient lift (also variously referred to as a patient hoist, jack hoist or hydraulic lift) may be either a sling lift or a sit-to-stand lift. These devices generally allow caregivers in hospitals and nursing homes to transfer patients between various sitting and standing positions using hydraulic power. 
         [0004]    Sling lifts are used for patients whose mobility is very limited. These are variously designed as mobile lifts or overhead lifts (suspended from ceiling-mounted or overhead tracks). Sit-to-stand lifts are designed to help patients who have some mobility but who lack the strength or muscle control to rise to a standing position. These lifts use a system of straps, vests, or belts (as opposed to slings) to make the transition possible. 
         [0005]    Most current lift units are designed to be able to pick up a patient in a sling and then move them from one hospital room to another using the wheels on the bottom of the legs. These lifts are effective in a hospital or nursing home setting, but their large size and weight along with their use of wheels for rotation and motion make them fairly ineffective in a home setting with tight walkways and carpet. The inability to mobilize patients at home is one of the primary reasons that patients find it necessary to leave the home environment and enter a nursing home when they become temporarily or permanently disabled. 
       SUMMARY OF THE INVENTION 
       [0006]    The lift of the present invention includes a lightweight, foldable lift that can be conveniently transported and stored in a home or car. According to a first preferred embodiment, the lift of the present invention may be operated as a caregiver lift to allow a typical caregiver to handle a patient under a wider variety of conditions and circumstances than the industrial sized lifts of the prior art. Further, the lift of the present invention is designed to allow a patient to be moved in all directions and to operate on a variety of surfaces. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0007]    The features and advantages of the present invention will be more clearly understood from the following description taken in conjunction with the accompanying drawings. 
           [0008]      FIG. 1  shows a basic design of the caregiver lift of the present invention. 
           [0009]      FIG. 2  shows a basic design of the caregiver lift of the present invention in an extended position. 
           [0010]      FIG. 3  shows the base housing of the caregiver lift of the present invention. 
           [0011]      FIG. 4  shows a preferred embodiment of the lifting mechanism of the present invention. 
           [0012]      FIG. 5  shows a preferred embodiment of the legs of the present invention. 
           [0013]      FIG. 6  shows a preferred embodiment of the arm of the present invention. 
           [0014]      FIG. 7  shows an alternative embodiment of the lifting mechanism of the present invention. 
       
    
    
       [0015]    Like reference numerals refer to like parts throughout the description of several views of the drawings. 
       DETAILED DESCRIPTION OF THE INVENTION 
       [0016]    For the purposes of promoting an understanding of the principles of the present invention, reference will now 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 present invention is hereby intended and such alterations and further modifications in the illustrated devices are contemplated as would normally occur to one skilled in the art. For instance, in many embodiments the present invention is discussed and referred to as a patient lift. However, it should be understood that the present invention may be used as a general lifting mechanism which can lift any of a variety items and/or people in a variety of circumstances. 
         [0017]    With reference now to  FIG. 1 , a first preferred embodiment of the present invention will now be discussed. As shown in  FIG. 1 , the major components of the caregiver lift of the present invention  100  preferably include a base housing  130  and a lifting mechanism  150 . As shown, the base housing  130  preferably supports a center post  134  and provides four pivoting mounts  111 ,  113 ,  115  and  117  for connecting four legs  110 ,  112 ,  114  and  116 . Preferably, the four legs  110 ,  112 ,  114  and  116  are composed of carbon fiber rectangular tubes that are pinned to the base housing. According to further preferred embodiment, feet or caps  120 ,  122 ,  124 ,  126  may be attached at the distal ends of each leg. According to a preferred embodiment, the feet and/or caps  120 ,  122 ,  124 ,  126  may be made of aluminum or other light weight metal. According to alternative embodiments, the feet and/or caps may alternatively be formed from or covered with non-slip material. 
         [0018]    As further shown in  FIG. 1 , the lifting mechanism  150  preferably includes a motor or gear arrangement for applying a lifting force to the arm  140 . According to a preferred embodiment, the lifting mechanism  150  of the present invention preferably includes a reducing worm gear set  154  which rotates a shaft and spools a carbon fiber ribbon  156 . This carbon fiber ribbon  156  wraps around an arm pivot  158  which effectuates raising the arm  140  when the crank or lever is turned. The arm  140  is preferably composed of a carbon fiber rectangular tube which is preferably designed to pivot on an aluminum or steel plug. At the distal end of the arm  140 , a plug  142  is preferably provided to attach to a harness clip or other connection mechanism. 
         [0019]    [ 0026 ]. With reference now to  FIG. 2 , the operation and design of a preferred embodiment of the present invention will now be further discussed. As shown in  FIG. 2 , the major components of the caregiver lift of the present invention  200  preferably include a base housing  241 , a lifting mechanism  250 , an arm  259  (shown in an extended position) and a crank  255  which may be removable or permanently attached. As shown, the base housing  241  supports a center post  237  and provides four pivoting mounts  229 ,  231 ,  233  and  235  for connecting four legs  211 ,  213 ,  215  and  217 . Preferably, the four legs  211 ,  213 ,  215  and  217  are composed of four carbon fiber rectangular tubes that are pinned to the base housing  241 . Further, feet or caps  221 ,  223 ,  225 ,  227  may preferably be attached at the distal ends of each leg. 
         [0020]    As further shown in  FIG. 2  and as discussed above, the lifting mechanism  250  preferably includes a reducing worm gear set  254  which rotates a shaft and spools a carbon fiber ribbon  256 . In operation, this carbon fiber ribbon  256  preferably wraps around an arm pivot  258  which effectuates raising the arm  259  when the crank or lever  255  is turned. The arm  259  is preferably composed of a carbon fiber rectangular tube which is preferably designed to pivot on an aluminum or steel plug. At the distal end of the arm  259 , a plug  257  is preferably provided to attach to a harness clip or other connection mechanism. 
         [0021]    Preferably, the manual crank or lever  255  may be geared such that it can be turned easily. According to preferred embodiment, the lifting mechanism  250  preferably includes a locking mechanism so that the arm is kept stationary while the patient is suspended and the crank  255  is unattended. While in an unlocked position, the arm  259  may preferably rotate  360  degrees while supporting a harness. Preferably, the crank  255  will hold its own position with or without a lock and regardless of the arm position of the lifting mechanism  250 . As discussed in more detail below, the lifting mechanism  250  may alternatively include a hydraulic lifting mechanism in place of the manual crank. Still further, the locking mechanism may be a hydraulic locking mechanism or a locking switch within the hydraulic lifting mechanism to keep the arm stationary. 
         [0022]    With reference now to  FIG. 3 , a preferred embodiment of the base housing  300  of the caregiver lift of the present invention will now be discussed. As shown in  FIG. 3 , the base housing  300  preferably contains at least two bearings  305  and  315  to constrain motion of the center post  365  to purely rotation. In operation, the base  300  also preferably serves as a pivoting mount  375  for each leg. As shown, each leg  245  is preferably connected to the base  300  via a bolt(s)  355 ,  356  or the like. Preferably, some variety of quick disconnect pin  335  may be used for securing the bolt(s)  355 ,  356  in place. 
         [0023]    Due to the extreme forces exerted under normal operation, it is preferred that the pins and bolts of the present invention be made of high strength steel (&gt;200 ksi) or similar material to keep from shearing when loaded. Additionally, because the base housing  300  of the present invention is subject to large amounts of stress, it is further preferred that it is made of high strength aluminum (&gt;70 ksi yield) or a high quality grade of stainless steel. 
         [0024]    With reference now to  FIG. 4 , a preferred embodiment of the lifting mechanism  400  of the present invention will now be discussed. As shown in  FIG. 4 , the lifting mechanism  400  may use a removable hand crank  410  which when engaged applies torque to a reducing worm gear set  420 . Preferably, the worm gear  420  is positioned to rotate a shaft  430  which in turn spools a carbon fiber ribbon  440 . As shown, the carbon fiber ribbon  440  is preferably wrapped around the arm pivot  450  so that, when the carbon fiber ribbon  440  is spooled, the arm  460  is raised. According to an alternative embodiment, the arm  460  may be actuated via a hydraulic pump, lead screw, electric drive or other force producing mechanism. For example, as shown in  FIG. 7 , an alternative embodiment of the present invention may include a lift mechanism  700  which includes an adjustable hydraulic pump  702  to lift and maneuver a patient in place of the hand crank  410  discussed above. 
         [0025]    [ 0032 ]. With reference now to  FIG. 5 , a preferred embodiment of the legs of the present invention will now be discussed. As shown in  FIG. 5 , an exemplary view of one of the four identical legs  500  of the present invention is provided. According to one preferred embodiment of the present invention, the dimensions of each carbon fiber rectangular tube  510  may be approximately 96.520 cm×2.54 cm×5.0800 cm (38 inches×1 inch×2 inches) with a preferred material thickness of approximately 0.50800 cm (0.2 inch) thickness. According to an alternative preferred embodiment, the dimensions of the rectangular tube  605  may be approximately 28 inches×1 inch×2 inches. At the proximal end  520  of a leg unit  500 , two brass bearings  540  may be provided for allowing connection to a pivoting mount  375  of the lift base  300  (as shown in  FIG. 3 ). Preferably, the distal end  530  of a leg unit  500  is covered with feet or caps  560  at the end. 
         [0026]    With reference now to  FIG. 6 , a preferred embodiment of the arm of the present invention will now be discussed. As shown in  FIG. 6 , a single arm  600  is shown. Preferably, the arm  600  of the present invention consists of a carbon fiber rectangular tube  605 . According to one preferred embodiment of the present invention, the dimensions of the carbon fiber rectangular tube  605  may be approximately 96.520 cm×2.54 cm×5.0800 cm (38 inches×1 inch×2 inches) with a material thickness of approximately 0.50800 cm (0.2 inch). According to an alternative preferred embodiment, the dimensions of the rectangular tube  605  may be approximately 28 inches×1 inch×2 inches. As shown, the proximal end  615  of the arm unit  600  may preferably include a connection point  625  for a carbon fiber ribbon  450  (shown in  FIG. 4 ). Further, the proximal end may further include an aluminum or steel plug  635  through its pivot point for connection to the lifting mechanism  150  (shown in  FIG. 1 ). Plug  635  may also act as a fastener for the carbon fiber ribbon  450 . At the distal end  645  of the arm  600 , a second aluminum or steel plug  655  may be further provided as an attachment point for a harness. 
         [0027]    According to a preferred embodiment of the present invention, the materials used for the present invention may include unidirectional carbon fiber for all tubes, martinsitic stainless (or hard coated) steel for all pins, shafts and arm pivot bracket, and 7075 or stronger tempered aluminum for the base. Alternatively, any materials with suitable strength characteristics may be used. 
         [0028]    While the above descriptions regarding the present invention contains much specificity, these should not be construed as limitations on the scope, but rather as examples. For example, several preferred dimensions and proportions for various aspects of the present invention are provided. However, it should be understood that each of the dimensions and proportions provided may be adjusted and/or changed based on the specific needs of a user. Further, the preferred embodiment of the present invention is shown having four legs. However, according to alternative preferred embodiments, the lift of the present invention may include alternative designs using any combination of three or more legs as needed. Still further, the present invention is discussed and disclosed with respect to the lifting of patients. However, it should be understood that the present invention may be used to lift or support any of a variety of items or individuals in a variety of settings without limitation. Further, the present invention may be modified and/or used in combination with any of a variety of attachments so that it may be customized for specific uses, such as for the lifting of a person into a tub or vehicle or over stairs.