Patent ID: 8752252

Claim:
A clasp comprising: a) a pair of pieces capable of being engaged with each other, and, when engaged, capable of both rotating about an axis line common to said both pieces, the pair comprising a first piece and a second piece; b) a respective permanent magnet for each of the pieces and each magnet being held in said respective piece; c) each magnet having front and rear surfaces, wherein each of the surfaces has alternating North and South magnetized poles, and when said both pieces are engaged, the respective front surfaces of the first and second pieces face each other and a North magnetized pole on the front surface of the first piece faces a South magnetized pole on the front surface of the second piece; d) means for causing the pair of pieces to release from each other merely by rotating one of the pieces relative to the other of the pieces about the axis line in either circumferential direction about the axis line until the respective front surfaces of the first and second pieces face each other with same magnetized poles and the pair of pieces release from each other due to magnetic repulsion between the magnets; e) the pieces including a projecting portion and a recessed portion receiving the projecting portion therein, the portions facing each other; and f) the projecting portion and the recessed portion having respective circumferential surfaces, each of the circumferential surfaces being formed by a cylindrical surface and coming into contact with each other in order to be capable of sliding about the axis line common to the both pieces.