초록 ▼

An improved power driven lumbosacral backrest having a back engaging contour which is adjustable under power of manual operation to accommodate users\backs which vary widely in configuration and dimension. It has a contour defined by a spindle inserted between a foundation frame and resilient back s

An improved power driven lumbosacral backrest having a back engaging contour which is adjustable under power of manual operation to accommodate users\backs which vary widely in configuration and dimension. It has a contour defined by a spindle inserted between a foundation frame and resilient back support, the regulator spindle being adjustable along the back support and adapted to define a transverse plane of rigidity at the proper level and shape to provide comfortable support for the individual user\s back. The backrest includes a pair of gear racks, a pair of gears and a series of rollers journaled to a shaft between the gears. A plurality of spaced apart flexible bands are trained over the rollers and gears.

대표청구항 ▼

A power driven lumbosacral backrest controlled by the user and comprising, in combination: (a) a foundation frame of plastic or metal with internal and external reinforcing ribs; (b) a pair of gear racks disposed one along each edge portion of the foundation frame; (c) a motor and reduction gear loc

A power driven lumbosacral backrest controlled by the user and comprising, in combination: (a) a foundation frame of plastic or metal with internal and external reinforcing ribs; (b) a pair of gear racks disposed one along each edge portion of the foundation frame; (c) a motor and reduction gear located at the lower center of the foundation frame and connected to a vertically extending reversible drive shaft; (d) a spindle disposed transversely of said foundation frame having a pair of axially spaced gears connected by a shift, each said gear engaging an adjacenet one of said pair of gear racks; (e) a plurality of axially spaced rollers freely journaled on said shaft between said pair of gears; (f) a series of flexible metallic bands trained over said rollers which rotate reversely of the direction of spindle travel; and (g) a connecting bracket interposed between said reversible drive shaft and said spindle.