Hydraulic chair lift mechanism.

摘要

A hydraulic lifting mechanism for an article of furniture (10) comprising a pair of sealed chambers (71, 26) interconnected with a hollow conduit (28) and containing hydraulic fluid. One of the chambers is expandable and comprises flexible walls (71) in the form of a rolling diaphragm. The second chamber (26) contains a pressurized gas in addition to a hydraulic fluid. The expandable chamber is located in the supporting base of the article of furniture. A two speed valve (30) is included in the interconnecting conduit for allowing fluid transfer between the chambers at a first rate in one direction and at a second rate in the other direction. The second chamber (26) and the control valve (30) can be located remotely from the base (12) of the article of furniture.