Abstract: A leg structure of an office chair comprises: a vertical support post coupled to the bottom of a support plate of an office chair, a leg coupled to the lower portion of support post, wherein the leg is defined with a fitting portion for the connection with the support post. At the periphery of fitting portion is outwardly arranged a plurality of leg racks in a radiation-shaped manner, and beneath the ends of leg racks are respectively provided with a sliding wheel, wherein an upright leg pillar is extendedly disposed at the lower end of the fitting portion, and a sliding wheel is mounted beneath the leg pillar for abutting against the floor, such that the leg pillar and the sliding wheel of leg pillar can support the weight of user so as to reduce the loading weights of leg racks of office chair, thus enabling to prolong the service lives of leg racks.

Abstract: An electronic dartboard comprises a dartboard frame in which a plurality of dartboard blocks are disposed. The dartboard blocks are formed of a dartboard body and a mounting seat in which the dartboard body is movably disposed. The dartboard frame is mounted in an outer frame which is provided with a score board and a circuit board. The dartboard frame is provided in the front with a plurality of protective frames, and in the back with an induction circuit film set. A cover plate is provided with a plurality of silencing holes and is fastened with the outer frame. A score display is separably connected to the circuit board.

Abstract: An electronic dartboard comprises a dartboard frame in which a plurality of dartboard blocks are disposed. The dartboard blocks are formed of a dartboard body and a mounting seat in which the dartboard body is movably disposed. The dartboard frame is mounted in an outer frame which is provided with a score board and a circuit board. The dartboard frame is provided in the front with a plurality of protective frames, and in the back with an induction circuit film set. A cover plate is provided with a plurality of silencing holes and is fastened with the outer frame. A score display is separably connected to the circuit board.

Abstract: An electronic dart comprises a frame, a target grille rotatable in the frame, protective frames on the target grille target blocks on sector-shaped spaces of the target grille, a sensor assembly, a rear board threadedly secured to both the target grille and the frame, and a score display board on the bottom being at a relative long distance from the dart for preventing from being hit by errant darts. A replacement of the damaged target block can be done by first disengaging the rear board and the target grille from the frame. Furthermore, score signal is wirelessly sent to the score display board.