Patent ID: 7896765

Claim:
A belt tension adjustment mechanism for use with a device including a main body and a belt pulley set, said belt pulley set including a belt, a driving pulley and a follower pulley, said belt tension adjustment mechanism comprising: a slab mounted on said main body and has a pivotal hole and a gliding slot; at least two tension pulleys disposed on said slab and contacted with opposite sides of said belt, wherein one of said at least two tension pulleys is arranged between said pivotal hole and said gliding slot, and said pivotal hole is disposed between said driving pulley and said follower pulley; and a fixing element penetrated through said pivotal hole and disposed between said at least two tension pulleys for facilitating said slab to be movably fixed on said main body, a confining element, which is moveable along said gliding slot for restraining the movable range of said slab, wherein a tight tension force and a slack tension force are exerted on said opposite sides of said belt to define a tight side and a slack side of said belt when said belt pulley set runs, wherein a counterforce is generated from said tight side of said belt to exert on said tension pulley contacting with said tight side, said slab is moved in response to said counterforce, and said slack side of said belt is suppressed by said tension pulley contacting with said slack side such that said slack tension force is adjustable.