초록 ▼

A chair for business or home use comprises a rotatable seat supported on a single leg at the bottom of which is a ball bearing caster. The leg is connected by a telescopically extensible arm to a pivot post which projects upwardly from the center of a circular base plate on which the ball bearing ca

A chair for business or home use comprises a rotatable seat supported on a single leg at the bottom of which is a ball bearing caster. The leg is connected by a telescopically extensible arm to a pivot post which projects upwardly from the center of a circular base plate on which the ball bearing caster is adapted to roll as the chair swings around the pivot post. The chair may also have a back rest which is mounted for universal movement on a back support which extends rearwardly from an upper portion of the chair leg and then upwardly. The ball bearing caster comprises a larger ball retained in a socket and resting on a circle of smaller bearing balls so that the larger ball can rotate freely in all directions. Alternatively the ball bearing caster comprises a plurality of balls in a retainer.

대표청구항 ▼

A chair comprising a base, a central pivot post projecting up from said base and defining a vertical axis of rotation, said base extending 360°around said pivot post, an upright support member spaced radially from said axis, telescopically extendible means coupling said upright support member with s

A chair comprising a base, a central pivot post projecting up from said base and defining a vertical axis of rotation, said base extending 360°around said pivot post, an upright support member spaced radially from said axis, telescopically extendible means coupling said upright support member with said central pivot post for rotation of said upright support member about said axis through an angle of 360°by rotation of said coupling means about said pivot post, and for limited movement of said upright support member toward and away from said central pivot post by telescopic extension or contraction of said coupling means, while maintaining said upright support member in an upright position, said telescopically extendible coupling means comprising two relatively movable parts and antifriction means between said two parts to provide for free movement of said parts relative to one another, a seat mounted at the upper end of said upright member, and single rolling support means at the lower end of said upright support member and rolling on said base upon rotation of said upright support member about said central pivot post and upon movement of said upright support member toward or away from said central pivot post, said rolling support means being capable of rolling in all directions on said base and comprising antifriction bearing means at the lower end of said upright support member to support said upright support member and seat on said base, said upright support member being supported vertically solely by said single rolling support means and being maintained in an upright position by said telescopically extendible coupling means.