초록 ▼

A backrest for vehicle seats includes an inverted U-shaped support frame having an upper cross bar, two side arms and a cross bar interconnecting the lower ends of the side arms. A shaft is rotatably mounted on said support frame parallel to and adjacent the cross bar and a plurality of flexible ele

A backrest for vehicle seats includes an inverted U-shaped support frame having an upper cross bar, two side arms and a cross bar interconnecting the lower ends of the side arms. A shaft is rotatably mounted on said support frame parallel to and adjacent the cross bar and a plurality of flexible elements extending generally vertically in side-by-side relation are connected at their upper ends to a first transverse element secured to the support frame and a lower transverse element which is connected to a pair of tensioning elements. The tensioning elements extend beneath the cross bar and upwardly over the guide bar extending between the side arms in the vicinity of the upper curved portion of the flexible elements which have an S-shaped configuration. A spacer cross member is disposed in engagement with the flexible elements in the vicinity of the upper curve and the upper ends of the tensioning elements extend over the guide bar and are connected to the spacer cross member. Radial arms are provided on the shaft which engage the tensioning elements so that upon rotation of the shaft the tensioning elements will exert a transverse force on the upper curvature of the flexible elements to vary the curvature of the flexible elements.

대표청구항 ▼

A backrest for vehicle seats with a support structure for the back of a person occupying the seat wherein said support structure comprises an inverted U-shaped frame member with an upper cross bar and two side arms having spaced apart lower ends, a bar interconnected between said lower ends and shaf

A backrest for vehicle seats with a support structure for the back of a person occupying the seat wherein said support structure comprises an inverted U-shaped frame member with an upper cross bar and two side arms having spaced apart lower ends, a bar interconnected between said lower ends and shaft means rotatably supported by said frame member for rotation parallel to said bar, an array of flexible elements extending generally vertically side-by-side and connected at opposite ends thereof to first and second transverse elements, said first transverse element being connected to said frame adjacent said upper cross bar and said second transverse element disposed parallel to said bar and said shaft means, said flexible elements having a generally S-shaped configuration with a lower forwardly convex curve for supporting the lumbar region of the back and an upper forwardly concave curve for supporting the upper dorsal region, a spacer cross member disposed parallel to said cross bar of said frame and disposed in engagement with said flexible elements adjacent said upper forwardly concave curve, guide bar means secured to said U-shaped frame member between said side arms and extending parallel to said cross bar, tensioning elements connected to said spacer cross member extending over said guide means, downwardly under said bar and upwardly into engagement with said second transverse element to act substantially radially on said upper curve of said flexible elements for applying a tensioning force to said flexible elements, operating means connected to said shaft means for rotating said shaft means and radial arms on said shaft means engaging said tensioning elements adjacent said bar whereby upon rotating said shaft means in a first direction, the tensioning elements increase the tensioning force that said spacer cross member applies to the flexible elements and said second transverse element is left free to move upwardly, while rotating the shaft means in a second direction opposite to said first direction the tensioning elements reduce the tensioning force applied to the flexible elements and pull downwards said second transverse element.