Patent attributes
A constricting device for the footrest ring of a chair includes a constricting unit assembled between the center tube of a chair and the conical sleeve of a footrest ring. The constricting unit consists of a constricting main body and a fixing ring combining the constricting main body and the sleeve of the footrest ring. The constricting main body is a conical body fitted with the conical sleeve of the footrest ring, having its center bored with a fitting hole to be fitted around the center tube of the chair and its circumferential wall cut with plural openings. When the footrest ring is pressed downward by treading, the conical sleeve of the footrest ring will press the conical constricting main body and make it constricted to closely hold the center tube of the chair, able to stably fix the footrest ring on the center tube of the chair.