Upright support bar

An upright support bar, comprising:

• an outer tube having one end thereof terminating in a nesting end and an opposite end thereof locked with a foot member;
• an inner tube having one end thereof locked with a foot member and an opposite end thereof terminating in an insertion end, said insertion end of said inner tube being inserted into said nesting end of said outer tube so that said inner tube is movable in said outer tube, said inner tube comprising a plurality of holes spaced along the axis direction thereof;
• a mount fastened to said nesting end of said outer tube and located at a position where said outer tube and said inner tube are connected with each other, said mount comprising two supporting pieces respectively disposed at two opposite sides thereof to support said inner tube therebetween and a receiving hole radially passing through a wall of said mount thereof;
• a button shaped like a long handle and mounted on the mount, said button comprising an actuation end, a mounting through hole and a finger grip, said actuation end and said finger grip being respectively located at two opposite ends of said button, said actuation end being provided with a latching portion, said latching portion being engaged into one of said holes of said inner tube to lock said inner tube to said outer tube when said actuation end is biased downward, said mounting through hole being disposed between said actuation end and said finger grip and being set along the width of said button;
• a torsion spring mounted in said mounting through hole;
• a pivot device inserted through said two supporting pieces of said mount, said mounting through hole of said button and said torsion spring to secure said button to said mount for allowing said button to be turned about said pivot device when a force is applied to said finger grip;
• a sliding block comprising a locking piece, said sliding block being mounted on said mount and movable relative to said mount between a first position where said locking piece is abutted against said button and a second position where said locking piece being away from said button;
• and
• an elastic damping device mounted in said receiving hole of said mount, said elastic damping device comprising a steel ball and a spring, said spring having one end thereof stopped by said sliding block and an opposite end thereof stopped against said steel ball, said steel ball having a part of the surface thereof exposed outside said receiving hole and being kept engaged in one of said holes of said inner tube.