Back for seating unit

摘要

A back for a seating unit, such as a chair, includes a back frame and a compliant back that is flexibly bendable to define different curvilinear shapes for sympathetically and ergonomically supporting a seated user's back. The back includes a bracket with forwardly-extending flanges pivotally connecting the compliant back to the back frame at a bottom connection generally aligned with a seated user's hip joint. The back also includes a top connection pivotally connecting the back to the back frame above the first connection. An adjustable torsional force-generating mechanism is connected to the first connection that biases a lumbar portion of the compliant back forward with respect to the chair. The top and bottom connections, in combination with the adjustable force generating mechanism, constrain the compliant back to move over a range that provides excellent ergonomic lumbar support to a seated user.