| 摘要 |
A chair seat pitch adjustment assembly which a user can adjust upwardly or downwardly with basically the same applied force. A seat support (70) is pivotally mounted with respect to a supporting assembly (10) at one point and is joined thereto at another point through a pivot bracket (81). The pivot bracket is pivotally mounted to the support assembly on one pivot axis (89) and to the seat support on a second pivot axis (82). The pivot bracket includes a cylindrical wall (81b) whose axis lies on the second pivot axis. The cylindrical wall includes at least one helically oriented slot (83) receiving a projection (93) from a slide (90) slidably mounted on the seat support member whereby movement of the slide one way or the other rotates the pivot bracket about the second pivot axis and thereby changes the relative elevation of the first pivot axis with respect thereto. This in turn changes the pitch of the seat support with respect to the underlying support assembly and thereby changes the pitch of a seat mounted thereon. |
