Abstract: A chair control has a threaded element with a thread extending along an axis. A retainer limits axial freedom of the threaded element and a user control rotates the threaded element. A spring backstop is threaded to the threaded element and a spring with a projection has this projection stopped against the spring backstop.

Abstract: A chair seat adjustment mechanism has a support, a back bracket for attachment to a chair back and a seat plate for attachment to a chair seat. The back bracket is pivotally mounted to the support at a first pivot. The seat plate, which extends above the support, is pivotally mounted to the back bracket at a second pivot and slidably hinged to the support at a third pivot. The second pivot is positioned above and rearwardly of the first pivot. The third pivot is positioned forwardly of the second pivot such that rearward titling of the back bracket draws the seat plate rearwardly and tilts a rear of the seat plate downwardly. The third pivot may be a pivot pin on the support slidably received in an elongate slot on the seat plate, which may be slightly declined towards the back. A chair having such a chair seat adjustment mechanism is more comfortable for some users.

Abstract: A height-adjustment mechanism may include an integral one-piece leverage body; an integral one-piece sleeve; and a locking member. In an embodiment, the integral one-piece leverage body has a handle, a pair of pivot pins projecting from opposed sides, a tongue projecting rearwardly, and a resilient biasing member projecting forwardly. These parts may be made of low cost materials suitable for integrally forming their features in an injection-moulding operation. Various features built in to these parts may provide a user with a sense of quality.

Abstract: The present invention provides a height-adjustment mechanism for an armrest. In an embodiment, a height-adjustment mechanism for an armrest includes an integral one-piece leverage body, and an integral one-piece sleeve. In an embodiment, the integral one-piece sleeve has pivot seats formed on a pair of locking arms depending from a first wall of the sleeve. These parts may be made of low cost materials suitable for integrally forming their features in an injection-moulding operation. Various features built into these parts may provide a user with a sense of quality.

Abstract: The present invention provides a switching apparatus having a design intended to reduce wear on its key part. In an embodiment of the invention, a rotatable member is rotatably fixed on a pivot. A slidable bearing member has a first surface for engaging the rotatable member in a non-sliding manner, and an opposite second surface for slidingly engaging an abutment. Any significant wear on the switching apparatus is more likely to occur between the sliding member and the abutment, rather than between the rotatable member and the sliding member. In an embodiment, one of the rotatable member and the slidable bearing member includes a protuberance, and the other of the rotatable member and the slidable bearing member includes a corresponding indentation for engagement with the protuberance. The join formed between the protuberance and indentation provides a substantially non-sliding engagement between the rotatable member and the slidable bearing member.