Raisable leg rest

Abstract

A raisable legrest for a wheelchair, the legrest comprising: a frame, to support a user's lower leg, the frame being attachable to the wheelchair, the frame being movable between a lowered position and a raised position about a pivot point when attached to the wheelchair; and a pivot point position adjustor, located between the pivot point and the wheelchair, for adjusting the position of the pivot point in at least a vertical direction; wherein the pivot point can be positioned by the pivot point position adjustor to be coaxial with an approximate center of rotation of a knee of the user.

We claim:  
     
         1 . A raisable legrest for a wheelchair, the leg rest comprising: 
 (a) a frame, to support a user's lower leg, said frame being attachable to the wheelchair, said frame being movable between a lowered position and a raised position about a pivot point when attached to said wheelchair; and    (b) a pivot point position adjustor, located between the pivot point and the wheelchair, for adjusting the position of the pivot point in at least a vertical direction; 
 wherein the pivot point can be positioned by the pivot point position adjustor to be coaxial with an approximate center of rotation of a knee of the user.  
   
     
     
         2 . The legrest according to  claim 1 , wherein said pivot point position adjustor is adjustable in at least a vertical direction by means of an extendable vertical support element which supports said pivot point.  
     
     
         3 . The legrest according to  claim 2 , wherein said extendable vertical support element includes a fastener to hold said extendable vertical support element at a fixed vertical height.  
     
     
         4 . The legrest according to  claim 2 , wherein said pivot point position adjustor further includes a holder and one of said extendable vertical support element or said holder is hollow, and said extendable vertical support element and said holder fit together to form a quick release coupling.  
     
     
         5 . The legrest according to  claim 4 , wherein one of said extendable vertical support element or said holder contains a notch, and the other of said extendable vertical support element or said holder contains a pin sized and shaped to engage said notch to form said quick release coupling.  
     
     
         6 . The legrest according to  claim 4 , wherein said pivot point position adjustor includes a pivot block, and said extendable vertical support element engages said holder at one end and said pivot block at the other end and is adjustably connected therebetween.  
     
     
         7 . The legrest according to  claim 6 , wherein said extendable vertical support element includes a vertical element which may be connected to said pivot block at one of a discrete number of connection points.  
     
     
         8 . The legrest according to  claim 7 , wherein said connection points comprise a discrete number of holes on one of said vertical element or said pivot block, and said pivot block may be connected to said vertical element by a bolt inserted through one of said holes.  
     
     
         9 . The legrest according to  claim 2 , wherein said extended vertical support element has a top end and a bottom end, and said pivot point is located towards said top end.  
     
     
         10 . The legrest according to  claim 4 , wherein said holder is a hollow cylinder.  
     
     
         11 . The legrest according to  claim 1 , wherein said pivot point position adjustor is adjustable in at least a vertical direction by means of a releasable clamp.  
     
     
         12 . The legrest according to  claim 11 , wherein said pivot point position adjustor further includes a vertical element which supports said pivot point, and wherein said vertical element is movable in a vertical direction when said releasable clamp is released, and said vertical element is set at a fixed vertical height when said releasable clamp is clamped.  
     
     
         13 . The legrest according to  claim 1 , wherein the pivot point position adjustor further includes a horizontal adjustor to adjust the position of the pivot point in a horizontal direction.  
     
     
         14 . The legrest according to  claim 13 , wherein the horizontal adjustor comprises a horizontal element and a releasable holder to hold said horizontal element.  
     
     
         15 . The legrest according to  claim 1 , wherein said frame has a length, said length being adjustable to accommodate the leg of the user.  
     
     
         16 . The legrest according to  claim 15 , wherein said frame has a footplate to receive a foot of the user.  
     
     
         17 . The legrest according to  claim 16 , wherein said frame has a top and a bottom, and said pivot point is located at the top of said frame and said footplate is located at the bottom of said frame.  
     
     
         18 . The legrest according to  claim 17 , wherein said lower leg of said user has a leg-length, the length of the frame can be adjusted so that the distance between the pivot point and the footplate is approximately equal to said leg-length, and wherein the frame remains at said adjusted length as the frame moves between the lowered and raised position.  
     
     
         19 . The legrest according to  claim 15 , wherein said frame comprises an upper frame attached to the pivot point and a lower frame slidably connected to the upper frame.  
     
     
         20 . The legrest according to  claim 19 , wherein one of the upper frame or the lower frame is hollow, and wherein the other of said upper frame or lower frame fits into the hollow frame.  
     
     
         21 . The legrest according to  claim 1 , further including a frame-stop to stop said frame from being movable beyond a predetermined lowered position.  
     
     
         22 . The legrest according to  claim 21 , wherein said frame-stop has an adjustable position, and wherein said predetermined lowered position of said frame can be adjusted by adjusting said position of said frame-stop.  
     
     
         23 . The legrest according to  claim 21 , wherein said frame-stop is attachable to at least one of said frame or said pivot point position adjustor.  
     
     
         24 . The legrest according to  claim 21 , wherein said frame-stop is a threaded screw.  
     
     
         25 . The legrest according to  claim 1 , further including: 
 (a) a calf support to further support the user's lower leg, said calf support being pivotally connected to the frame at a frame pivot point;    (b) an actuator, to apply a force on the calf support, to move said frame between the lowered position and the raised position; and    (c) a compressible positioning element, positioned between the calf support and the frame, for permitting the calf support position relative to said frame to be varied as a moment about said frame pivot point changes; 
 wherein, as said moment increases about said frame pivot point, said compressible positioning element compresses, and said calf pad support moves closer to said frame to provide support to the lower leg of the user.  
   
     
     
         26 . The legrest according to  claim 25 , wherein the compressible positioning element defines a predetermined pivot angle between the calf support and the frame when the frame is in the lowered position.  
     
     
         27 . The legrest according to  claim 25 , wherein the calf support comprises a push plate and a calf pad mounted on the push plate.  
     
     
         28 . The legrest according to  claim 27 , where the calf pad is adjustably connected to the push plate.  
     
     
         29 . The legrest according to  claim 27 , wherein the compressible positioning element is a resilient material and is positioned between the frame and the push plate of the calf support.  
     
     
         30 . The legrest according to  claim 27 , wherein the compressible positioning element can be positioned at one of a number of predetermined locations between the frame and the push plate.  
     
     
         31 . The legrest according to  claim 29 , wherein the compressible positioning element is rubber.  
     
     
         32 . The legrest according to  claim 26 , further including an adjustable stop to restrict the pivot range of the calf support.  
     
     
         33 . A raisable legrest for a wheelchair to raise a lower leg of a user, the legrest comprising: 
 (a) a frame, said frame being attachable to the wheelchair, said frame being movable between a lowered position and a raised position about a pivot point when attached to said wheelchair;    (b) a calf support to support the user's lower leg, said calf support being pivotally connected to the frame at a frame pivot point;    (c) an actuator, to apply a force on the calf support, to move said frame between the lowered position and the raised position; and    (d) a compressible positioning element, positioned between the calf support and the frame, for permitting the calf support position relative to said frame to be varied as a moment about said frame pivot point changes; 
 wherein, as said moment increases about said frame pivot point, said compressible positioning element compresses, and said calf pad support moves closer to said frame to provide support to the lower leg of the user.  
   
     
     
         34 . The legrest according to  claim 33 , wherein the compressible positioning element defines a predetermined pivot angle between the calf support and the frame when the frame is in the lowered position.  
     
     
         35 . The legrest according to  claim 33 , wherein the calf support comprises a push plate and a calf pad mounted on the push plate.  
     
     
         36 . The legrest according to  claim 35 , where the calf pad is adjustably connected to the push plate.  
     
     
         37 . The legrest according to  claim 35 , wherein the compressible positioning element is a resilient material and is positioned between the frame and the push plate of the calf support.  
     
     
         38 . The legrest according to  claim 35 , wherein the compressible positioning element can be positioned at one of a number of predetermined locations between the frame and the push plate.  
     
     
         39 . The legrest according to  claim 37 , wherein the compressible positioning element is rubber.  
     
     
         40 . The legrest according to  claim 33 , further including an adjustable stop to restrict the pivot range of the calf support.