Patent ID: 7080887

Claim:
A chair comprising: a base frame unit including a seat frame with front and rear frame portions; a leg rest frame connected pivotally to said front frame portion of said seat frame and pivotable relative to said seat frame about a first pivot axis between a folded position, where said leg rest frame is disposed under said seat frame and is generally parallel to said seat frame, and an unfolded position, where said leg rest frame is generally coplanar with said seat frame; an operating unit including a drive shaft extending along a shaft axis parallel to the first pivot axis, mounted rotatably on said base frame unit, and disposed rearwardly of the first pivot axis, and an operating lever connected to one end of said drive shaft and operable so as to drive rotation of said drive shaft about the shaft axis; and a linkage device interconnecting said drive shaft and said leg rest frame, said linkage device being responsive to rotation of said drive shaft so as to drive movement of said leg rest frame from one of the folded and unfolded positions to the other of the folded and unfolded positions; wherein said linkage device includes: a first link member having a first link end connected co-rotatably to said drive shaft, and a second link end; a second link member having a rear link end connected pivotally to said second link end, and a front link end; a third link member having a first link portion connected pivotally to said front link end, a second link portion, and an intermediate link portion between said first and second link portions and connected pivotally to said base frame unit; and a fourth link member having a rear link section connected pivotally to said second link portion, and a front link section connected pivotally to said leg rest frame.