A chair chassis includes: a base, provided with an accommodation chamber; a backrest support; a memory stopper, disposed on the backrest support, wherein the memory stopper is provided with a first arc surface facing the base; a locking slider, slidably disposed in the accommodation chamber of the base, wherein the locking slider is provided with a second arc surface disposed opposite to the first arc surface, and a side of the locking slider is provided with a first rack; a first elastic member; and an elastic slider, slidably disposed in the accommodation chamber of the base, wherein one end of the elastic slider is provided with a second rack, wherein the second rack is meshable with the first rack. Accordingly, the chair chassis according to the embodiments of the present disclosure achieves reclination memory adjustment of a backrest of the chair.

A chair chassis includes: a base, provided with an accommodation chamber; a backrest support; a memory stopper, disposed on the backrest support, wherein the memory stopper is provided with a first arc surface facing the base; a locking slider, slidably disposed in the accommodation chamber of the base, wherein the locking slider is provided with a second arc surface disposed opposite to the first arc surface, and a side of the locking slider is provided with a first rack; a first elastic member; and an elastic slider, slidably disposed in the accommodation chamber of the base, wherein one end of the elastic slider is provided with a second rack, wherein the second rack is meshable with the first rack. Accordingly, the chair chassis according to the embodiments of the present disclosure achieves reclination memory adjustment of a backrest of the chair.

Chairs, seating systems, chair sub-assemblies and sub-systems, and associated methods of assembly and use. Aspects relate to chairs and methods of assembling chairs including chair controls of a relatively compact and effective design with desirable synchronous raising and tilting motions. Aspects also relate to tilt lock assemblies for achieving secure and effective tilt securement. Additional aspects relate to forward and rearward adjustment, or extension and retraction, of a seating assembly of the chair.

An adjustable chair has a seat and a splat. The seat has a lower base, an upper base, a tilt adjusting device, a lower rotating shaft, and an upper rotating shaft. The lower base has an assembling space. The upper base is movably deposited on the lower base. The tilt adjusting device is deposited in the assembling space. The lower rotating shaft is rotatably deposited in the lower base and connected to the tilt adjusting device. The upper rotating shaft is deposited in the upper base. The splat is tiltably connected to the seat and has a backrest unit and two connecting legs. The backrest unit is deposited at a rear side of the seat. The connecting legs are connected to the backrest unit, are connected to the lower rotating shaft, and are pivotally connected to the upper rotating shaft.

A multifunctional swivel chair tray includes a main body. The main body is connected with a warping plate through a second rotating shaft. An ascending and descending block penetrates through the second rotating shaft. The ascending and descending block is connected with an ascending and descending driving mechanism. A first adjusting rod penetrates through one side of the main body. The first adjusting rod is connected with a multi-spring grouping adjusting mechanism. A second adjusting rod is arranged on another side of the main body. The second adjusting rod is connected with a gear adjusting mechanism. The warping plate is connected with a base plate through a third rotating shaft. A slide plate is slidably connected onto the base plate. A slide plate locking mechanism is arranged between the base plate and the slide plate.

A multifunctional swivel chair tray includes a main body. The main body is connected with a warping plate through a second rotating shaft. An ascending and descending block penetrates through the second rotating shaft. The ascending and descending block is connected with an ascending and descending driving mechanism. A first adjusting rod penetrates through one side of the main body. The first adjusting rod is connected with a multi-spring grouping adjusting mechanism. A second adjusting rod is arranged on another side of the main body. The second adjusting rod is connected with a gear adjusting mechanism. The warping plate is connected with a base plate through a third rotating shaft. A slide plate is slidably connected onto the base plate. A slide plate locking mechanism is arranged between the base plate and the slide plate.

A chair of an aspect of the present disclosure includes: a support base; and a chair body including a seat frame that extends in the forward-rearward direction and forms at least part of a seat, and a back frame that is provided in the rear end of the seat frame to be pivotable around an axis O1 extending in the left-right direction, extends upward from the seat frame, and forms at least part of a backrest. The support base includes a slider that supports, in front of the axis O1, the seat frame movably in the forward-rearward direction, and a backrest-supporting shaft that supports, below the axis O1, the back frame pivotably around an axis O2 extending in the left-right direction.

A chair can include a chair back, or backrest, that is coupled to a base of a chair above a seat of the chair. A tilt mechanism can attach the backrest to the base. In some embodiments, the tilt mechanism can be configured so that the backrest rotates about multiple pivots as it reclines from an upright position to a reclined position to drive motion of the seat during recline of the backrest.

A furniture system includes a base, a first linkage and a second linkage. The base is configured to be disposed on a flat surface and to be connected to an article of furniture. The first linkage is connected to the base and configured to be connected to the article of furniture. The first linkage is configured to be actuated to cause the article of furniture to translate relative to the base. The second linkage is connected to the first linkage. The second linkage is biased into a locked state in which the second linkage prevents movement of the first linkage. The second linkage is configured to be actuated by an applied force into an unlocked state in which the second linkage allows movement of the first linkage (and the article of furniture to which the first linkage is configured to be connected).

A chair can include a chair back, or backrest, that is coupled to a base of a chair above a seat of the chair. A tilt mechanism can attach the backrest to the base. In some embodiments, the tilt mechanism can be configured so that the backrest rotates about multiple pivots as it reclines from an upright position to a reclined position to drive motion of the seat during recline of the backrest.