Swivel chairs rotate about a vertical axis. These were invented by Thomas Jefferson in the United States. They are often found on casters as well. Swivel desk chairs are available in many varieties and in vibrant colors. These are made by the best quality craftsmanship available. They make any office complete and are comfortable to sit and work in. They give built-in lumbar support, pneumatic seat elevation adjustment, rear height and seat depth correction.
A swivel is a connection that allows the connected object, such as a gun or chair to spin horizontally or vertically. A regular design for a swivel is a cylindrical shaft that can turn freely inside a support structure. The rod is usually held in place by a nut, washer or by thickening the rod. The apparatus can be connected to the ends of the rod or the center. Another familiar design is a ball that is able to revolve, within a support structure.
A third design is an empty cylindrical rod that has another rod that is smaller, inside. They are prevented from separating by flanges. The device may be connected to either end. A swivel joint for a pipe is often a threaded link, in which at least one of the pipes is bent, often at an angle of 45 or 90 degrees. The connection is squeezed, enough to be water or air tight and then tightened further.
A part found in rolling chairs, called the caster, is a type of wheel mounted with an offset navigation pivot. This enables the wheel to automatically rotate to line up with the direction from which it is pushed. Internet provides access to various websites displaying different types of swivel chairs, along with beautiful pictures. Some offer a gallery of pictures of swivel chairs, with a slideshow.