US Patent 7121516 Clamping stand

An improved clamping stand includes a clamp clamping the leaf of a desk and composed of an upper clamping plate and a lower clamping plate which are connected by a bolt and a pair of adjustable threaded rods with a C-shaped guard plate engaged therebetween, a pair of identical cushions respectively disposed on the inner surface of the upper and lower clamping plate for preventing the surfaces of the leaf from damaged and a tubular upright having a lower end connected to a top of the upper clamping plate and an upper end capable of supporting a LCD screen, a document board and/or a book tray which is supported by a pair of clamping stands synchronously, wherein the pair of threaded rods can adjust the oblique angle of the tubular upright.