Seat-raiser chair has wings seat and back with four-point linkage extending onto swivel crossbars

摘要

Seat-raiser chair has wings seat and back uses four-point linkage extended onto swivel crossbars so a linear drive push rod actuates the chair seat position changes from basic to raised. One rod (13) of the four-rod linkage is extended beyond the side hinge point (14) and fixed with the extensions (15) to the second swivel crossbar (12), and an adjuster lever (16) reaches up from the crossbar to be hinged on the side furthest from the linear drive (9) push rod (10). The first swivel crossbar (11) is rigidly joined as coupled to the two function arms (17) of the footrest (5) and/or chair back (6) drive elements assisted by stops (18) on the chair wings (1) engaged by the levers in the basic chair setting. These also allow the chair to be swiveled back into basic setting from the position with the footrest extended and/or back in repose. The stops also prevent any movement beyond the basis setting in which the drive push rod (10) lies between its two end states so that as the push rod moves beyond basic so the drive (9) housing exerts a pull on the linkage (7) and raises this to the position assisting the stand-up movement.