The invention relates to a hub construction for a rotatable chair, which automatically returns to the initial position when the chair is relieved. In a prior art hub the return force was counteracted mainly by the friction in the hub bearing, which, regardless thereof that the hub was loaded, was not always sufficient for the hub to maintain its rotational position, for example, when the sitting person lifted his feet off the floor. For obtaining higher friction when the hub is loaded, it has been provided with a brake. The brake can preferably be a pair of spring discs which are compressed when the hub is loaded, whereby the brake disc makes contact with the brake surface.

An exercise chair that is operable to engage a user's core muscle groups in order to maintain a desired position thereof. The exercise chair includes a base having a plurality of legs. A seat member is rotatably secured to the base. A first mounting plate is secured to the bottom of the seat member. A second mounting plate is secured to the first mounting plate. The second mounting plate is ring-shaped and undulated in form having at least two peak section and at least two valley sections. A wheel assembly is superposed the base and includes wheels configured to engage the second mounting plate and traverse therealong. A mount having a shaft coupled thereto rotatably couples the seat member with the base. In a first position of the exercise chair, the wheels of the wheel assembly are engaged with the at least two peak sections.

The invention relates to a chair (10) having a base (40) and a support (20), articulated thereon, that is coupled to a seating surface (11) and supports the latter, the seating surface (11) being connected to the support (20) rotatably or pivotably around a rotation axis (30) between a sitting position and a raised position, and the support (20) comprising at least one receiving region (28, 29) for aligned abutment of a juxtaposed chair (10) of identical design. Provision is made in this context that in the raised position, the seating surface (11) is pivoted out of the receiving region (28, 29) of the support (20) and exposes it. The result is to create a chair (10) that, for storage, can be juxtaposed in space-saving fashion with chairs (10) of identical design.

A furniture swivel for rotatably coupling first and second furniture components is disclosed. The furniture swivel includes a base, a rotor, and a retainer. The base may have a lower end for connecting to a first furniture component and an upper end including a planar base bearing surface. The rotor may have an upper end having a first portion for connecting to a second furniture component, and a lower end including a planar rotor bearing surface in sliding contact with the base bearing surface to form a plane bearing absent rolling elements for supporting the rotor and the first furniture component on the base. The retainer may be coupled to the base for substantially inhibiting translation of the rotor relative to the base.

A furniture swivel for rotatably coupling first and second furniture components is disclosed. The furniture swivel includes a base, a rotor, and a retainer. The base may have a lower end for connecting to a first furniture component and an upper end including a planar base bearing surface. The rotor may have an upper end having a first portion for connecting to a second furniture component, and a lower end including a planar rotor bearing surface in sliding contact with the base bearing surface to form a plane bearing absent rolling elements for supporting the rotor and the first furniture component on the base. The retainer may be coupled to the base for substantially inhibiting translation of the rotor relative to the base.

A piece of seating furniture having a base and a seat unit, wherein the base and the seat unit have provided between them a pivot bearing including a base-side bearing device and a seat-unit-side bearing device, via which the seat unit is rotatable about a vertical axis in relation to the base, and the pivot bearing has a switchable blocking device, via which the rotary movement capability of the bearing devices in relation to one another can be blocked.

A furniture swivel for rotatably coupling first and second furniture components is disclosed. The furniture swivel includes a base, a rotor, and a retainer. The base may have a lower end for connecting to a first furniture component and an upper end including a planar base bearing surface. The rotor may have an upper end having a first portion for connecting to a second furniture component, and a lower end including a planar rotor bearing surface in sliding contact with the base bearing surface to form a plane bearing absent rolling elements for supporting the rotor and the first furniture component on the base. The retainer may be coupled to the base for substantially inhibiting translation of the rotor relative to the base.

A portable stool that is configured to provide support for a user in an upright position wherein the present invention further provides controlled rotational movement for the user. The present invention includes a seat member wherein the seat member is supported by leg members. The leg members are adjustable in length and placed at an angle so as to angularly position the seat member at an angle of approximately thirty degrees when the portable stool is in its deployed state. The seat member includes a base member wherein the base member is rotationally coupled to a top portion of the seat member. Movement members are operably coupled to the base member and top portion of the seat member and provide a biased return to a neutral position ensuing the top portion of the seat member being rotatably moved. Light modules are present on the leg members.

According to an example aspect of the present invention, there is provided a hub for a rotatable chair, comprising a swivel shaft, a swivel shell arranged rotatably around the swivel shaft and a locking piston placed axially movably within the swivel shaft. There is a hole in the swivel shaft and a ball is placed movably in the hole. The ball is movable to a pocket in the swivel shell and an actuating mechanism is arranged for moving the locking piston in longitudinal direction of the swivel shaft for pushing the ball to the pocket and releasing it therefrom through the hole.