Lock release latch assembly for a collapsible chair having a fold-down back

Abstract

A collapsible chair including a seat, a pair of arm rests at opposite sides of the seat, a rotatable fold-down back, and a lock release latch assembly that is manually accessible at the rear of the fold-down back. The lock release latch assembly has a rotatable latch that is connected by way of first and second locking cables to a pair of locking pins that extend from opposite sides of the fold-down back to be removably attached to respective ones of the pair of arm rests. A lifting force applied to the latch causes a corresponding pulling force to be applied to each of the pair of locking pins via the first and second locking cables, whereby the locking pins are withdrawn from the pair of arm rests. Accordingly, the fold-down back of the collapsible chair is rotatable from an upright position standing generally vertically upward relative to the seat to a generally horizontal folded position lying above the seat in face-to-face alignment therewith. With the fold-down back rotated to its folded position, the chair will have a compact, space-efficient configuration which is suitable for storage and/or transport without requiring that the chair be disassembled.

1 . A collapsible chair including a seat, a rotatable fold-down back, a pair of arm rests located at opposite sides of the seat, and a lock release latch assembly, said lock release latch assembly comprising:
 a latch having first and second latch positions;   a locking projection extending from the rotatable fold-down back to be removably attached to a corresponding one of said pair of arm rests to lock the rotatable fold-down back in an upright position standing generally vertically above the seat; and   a locking linkage extending between said latch and said locking projection,   said latch having said first latch position at which said locking linkage is relaxed and said locking projection is attached to the one of said pair of arm rests for locking the rotatable fold-down back in said upright position, and said latch having said second latch position at which a pulling force is applied to said locking linkage for causing said locking projection to be removed from the one of said pair of arm rests for unlocking the rotatable fold-down back and thereby permitting said fold-down back to rotate towards the seat to a folded position.   
   
   
       2 . The collapsible chair recited in  claim 1 , wherein the latch of said lock release latch assembly is manually accessible at the rear of the rotatable fold-down back. 
   
   
       3 . The collapsible chair recited in  claim 1 , said chair also including a back rest support located within and surrounded by the rotatable fold-down back, said lock release latch assembly also comprising a latch housing carried by said back rest support, and said latch being mounted within said latch housing and movable therewithin between said first and second latch positions. 
   
   
       4 . The collapsible chair recited in  claim 3 , wherein said latch is pivotally mounted in said latch housing so as to rotate in response to a force applied thereto from said first latch position, at which said locking linkage is relaxed and said locking projection is attached to the one of said pair of arm rests, to said second latch position, at which a pulling force is applied to said locking linkage and said locking projection is removed from the one of said of pair of arm rests. 
   
   
       5 . The collapsible chair recited in  claim 4 , said lock release latch assembly also comprising a spring located in said latch housing, said spring being compressed to store energy when said latch rotates to said second latch position in response to said force applied thereto, said spring releasing the energy stored thereby and expanding so as to urge said spring to return to said first spring position when the force applied to said latch is terminated. 
   
   
       6 . The collapsible chair recited in  claim 1 , said lock release latch assembly also comprising a hollow locking collar located at one side of the rotatable fold-down back, said locking projection being removed from the one of said pair of arm rests and sliding through said hollow locking collar for unlocking the fold-down back when said latch has said second latch position and said pulling force is applied to said locking linkage extending between said latch and said locking pin. 
   
   
       7 . The collapsible chair recited in  claim 6 , said lock release latch assembly also comprising a pivot located at the one side of the rotatable fold-down back, said pivot extending from the one side of the fold-down back to the one of said pair of arm rests in order to establish a pivot axis around which the fold-down back rotates from said upright position towards the seat to said folded position when said latch has said second latch position and the fold-down back has been unlocked. 
   
   
       8 . The collapsible chair recited in  claim 7 , said lock release latch assembly also comprising a side bracket located at the one side of the rotatable fold-down back, each of said hollow locking collar and said pivot extending from said side bracket towards the one of said pair of arm rests. 
   
   
       9 . The collapsible chair recited in  claim 6 , said lock release latch assembly also comprising a spring located in said hollow locking collar, said spring being compressed within said hollow locking collar to store energy when said locking projection is removed from the one of said pair of arm rests so as to slide through said locking collar in response to said pulling force applied to said locking linkage when said latch has said second latch position, and said spring expanding and releasing the energy stored thereby for pushing said locking projection through said hollow locking collar and into attachment with the one of said pair of arm rests when the pulling force applied to said locking linkage is terminated. 
   
   
       10 . The collapsible chair recited in  claim 9 , said lock release latch assembly also comprising a stationary locking plug located within said hollow locking collar such that said spring lies between said locking projection and said stationary locking plug, said spring being compressed between said locking projection and said stationary locking plug in response to said pulling force applied to said locking linkage and the removal of said locking projection from the one of said pair of arm rests when said latch has said second latch position. 
   
   
       11 . A collapsible chair including a seat, a rotatable fold-down back, a pair of arm rests located at opposite sides of the seat, and a lock release latch assembly, said lock release latch assembly comprising:
 a latch having first and second latch positions;   first and second locking pins projecting outwardly from first and opposite sides of the rotatable fold-down back to be removably attached to respective ones of said pair of arm rests in order to lock the rotatable fold-down back in an upright position standing generally vertically above the seat; and   a first locking cable extending between said latch and said first locking pin and a second locking cable extending between said latch and said second locking pin,   said latch having said first latch position at which said first and second locking cables are relaxed and said first and second locking pins are attached to the respective ones of said pair of arm rests for locking the rotatable fold-down back in said upright position, and said latch having said second latch position at which a pulling force is applied to each of said first and second locking cables for causing said first and second locking pins to be removed from the respective ones of said pair of arm rests for unlocking the rotatable fold-down back and thereby permitting said fold-down back to rotate towards the seat to a folded position.   
   
   
       12 . The collapsible chair recited in  claim 11 , said chair also including a back rest support located within and surrounded by the rotatable fold-down back, said lock release latch assembly also comprising a latch housing carried by said back rest support, and said latch being pivotally mounted within said latch housing and rotatable therewithin between said first and second latch positions, said latch being manually accessible at the rear of the rotatable fold-down back so as to receive a manually-applied force for causing said latch to rotate from said first latch position to said second latch position. 
   
   
       13 . The collapsible chair recited in  claim 11 , said lock release latch assembly also comprising first and second hollow locking collars located at the first and opposite sides of the rotatable fold-down back, said first and second locking pins being removed from the respective ones of said pair of arm rests and slidable through respective ones of said first and second locking collars for unlocking the rotable fold-down back when said latch has said second latch position and said pulling force is applied to each of said first and second locking cables extending between said latch and said first and second locking pins.