A linear actuator for adjusting a piece of furniture comprises a motor having a motor shaft, a conversion arrangement coupled to the motor shaft and adapted to convert a rotational movement generated by the motor shaft into an elongation of the linear actuator, and a locking arrangement coupled directly or indirectly to the motor shaft and adapted to selectively cause rotation locking of the motor shaft by means of a locking element. The locking arrangement comprises an inner part with at least one inner chamber and an outer part radially surrounding the inner part and having at least one outer chamber. The outer part and the inner part are rotatable relative to each other in such a way that the at least one inner chamber and the at least one outer chamber can be aligned with each other. The rotation locking is activated by clamping the locking element between the at least one inner chamber and the at least one outer chamber by means of rotation of the inner part and the outer part relative to each other.

Proposed is a seat retainer in which first outer teeth and first inner teeth or second outer teeth and second inner teeth are engaged with each other at an angle, thereby a gap between a gear plate and a first flange or between the gear plate and a second flange can be removed.

Proposed is a seat retainer in which first outer teeth and first inner teeth or second outer teeth and second inner teeth are engaged with each other at an angle, thereby a gap between a gear plate and a first flange or between the gear plate and a second flange can be removed.

In one aspect, an active exercise chair comprises: a seat support, wherein the seat support is rigidly affixed to a top section of a shaft of a gas spring; a seat, wherein the seat is connected to the seat support; a seatback support, wherein the seatback support is pivotably connected to the seat support about a discrete pivot point; a seatback carriage, wherein the seatback carriage is slidably connected to the seatback support, wherein the seatback carriage is connected to a seatback, and wherein the seatback traverses a translational path defined by a geometry of the seatback carriage and the seatback support.

A therapeutic massage chair is reclinable between a horizontal and inclined position. The chair includes an upper back support member and a lower support member that is axially movable along a support frame, and is also rotatable about an axis which is perpendicular to the plane of the upper back support member. Electric linear actuators are provided to recline the therapeutic massage chair, and both axially move and oscillate the lower body support member. The therapeutic massage chair may be fitted with a controller system which allows the chair to be operated wirelessly from a mobile device running a mobile application, which may communicate with a web-based portal and/or database.

A therapeutic massage chair is reclinable between a horizontal and inclined position. The chair includes an upper back support member and a lower support member that is axially movable along a support frame, and is also rotatable about an axis which is perpendicular to the plane of the upper back support member. Electric linear actuators are provided to recline the therapeutic massage chair, and both axially move and oscillate the lower body support member. The therapeutic massage chair may be fitted with a controller system which allows the chair to be operated wirelessly from a mobile device running a mobile application, which may communicate with a web-based portal and/or database.

The present application provides an intelligent sofa mechanical extension device, including a base, a driving component and an extension component, where the driving component and the extension component are disposed on the base. The driving component includes a motor and a motor guide rail that are disposed on the base. The motor guide rail is provided with a motor moving slider in a slidable manner. An end of the motor is connected to the moving slider. The moving slider is connected to a driving rod through a drive connector. The driving rod is disposed on the seat cushion support assemblies on the left and the right side. The extension component is driven to stretch or retract with back-and-forth movement of the motor moving slider along the motor guide rail.

A medical chair includes a base, a seat section, and a leg rest pivotally mounted relative to the seat and adapted to move between an extended position and a retracted position. The chair further includes a scissor mechanism coupled to the leg rest to extend and contract the leg rest and an actuator mounted on one end relative to the seat section and having an extendible driving end coupled to the leg rest wherein when the extendible driving end extends the extendible driving end pivots the leg rest about the pivot axis and extends the scissor mechanism.

A medical chair includes a base, a seat section, and a leg rest pivotally mounted relative to the seat and adapted to move between an extended position and a retracted position. The chair further includes a scissor mechanism coupled to the leg rest to extend and contract the leg rest and an actuator mounted on one end relative to the seat section and having an extendible driving end coupled to the leg rest wherein when the extendible driving end extends the extendible driving end pivots the leg rest about the pivot axis and extends the scissor mechanism.

A folding chair includes front and rear supports that fold and/or retract into central beams to reduce the space occupied by the chair in a folded configuration. A backrest is coupled to the central beams with a hub that allows an angle of the backrest relative to the central beams to be selected and for the backrest to be folded flat relative to the central beams. One or more actuators and pin actuators may control the relative movements of the backrest, front support, rear support, and central beams.