Shaker

Claim 1

A shaker used for shake culture and the like, comprising: a horizontal fitting stand; a motor installed on the fitting stand; a driving disc centrally arranged on the fitting stand with a rotation shaft extending forward therethrough, said driving disc being connected with a driving shaft of the motor by a transmission means; a central support leg installed through a fixture to the driving disc, said central support leg being eccentrically adjustable with respect to the rotation shaft of the driving disc; a shake table having a back plate with a central fitting hole and a plurality of peripheral fitting holes; a rolling-contact bearing rotatably holding the central support leg; a plurality of peripheral support legs held by a plurality of peripheral rolling-contact bearings in the peripheral fitting holes; a plurality of free discs each having a rotation shaft rotatbly held by a further roller contact bearing on the fitting stand; and a plurality of peripheral magnets each securely held by one of the peripheral support legs in sliding engagement with one of the free discs, a magnetic attraction force being established between each magnet and the respective free disc which force is less than a rotation force produced by the motor so as to promote eccentric self adjustment of the magnets to conform with the eccentricity of the central support leg.