| 摘要 |
<p>A seat back adjustment unit (20) including a seat attaching plate (22) which is fixedly secured to the seat (28) of a chair and a back mounting plate (24) which will have mounted thereon the customary seat back (30). The seat attaching plate (22) has an upwardly and rearwardly curved portion (34) on which there is mounted an adjustment unit (26). The adjustment unit (26) in turn carries a lower generally horizontal portion (44) of the back mounting plate (24). The adjustment unit (26) includes a housing (52) which is guidedly mounted on the curved rear portion (34) of the seat attaching plate (22) while the same housing (52) has guidedly received therein the lower portion (44) of the back mounting plate (24). The adjustment unit (26) includes within the housing (52) thereof a reduction gear drive unit (70) which includes two driven member interlocked by pin and slot connections to the seat attaching plate (22) and the back mounting plate (24) for selective relative movement between the plates and the housing of the adjustment unit (26). A single actuator (86) is selectively positionable to drive a selective half of the reduction gear drive unit (70) to adjust either the tilt or the position of the seat back (30).</p> |
