Abstract: A sprung seat frame comprises a base element, a top element and a spring arrangement between the base and top elements. The spring arrangement has at least two leaf springs which are arranged one above the other at a spacing from each other and at least approximately parallel to each other. One end portion of each leaf spring is connected to the base element and the second end portion of each leaf spring is connected to the top element. The leaf springs are disposed obliquely inclinedly between the base and top elements. At least one corrector leaf spring which is oriented at least approximately parallel to the leaf springs and which is shorter than same is additionally operatively disposed between the base and top elements for optimizing the springing characteristic of the seat frame.

Abstract: Described is a seat (10) having a spring means (36) with which the springing characteristic of the seat (10) can be adjusted as desired. For that purpose a two-armed pivot lever (38) is provided on a back element (34) of the seat (10) at least approximately horizontally and is pivotable about a central mounting axis (40). At least one at least approximately horizontally arranged tension spring (48) is fixed by its one end portion (50) to the one arm (44) of the pivot lever (38), the second end portion (54) of the tension spring (48) being fixed to a fixing portion (56) of a support lever (58). The fixing portion (56) is at least approximately aligned with the mounting axis (40). The support lever (58) is mounted pivotably to the back element (34) and is pivotally connected by its fixing portion (56) to a scissor element (18) of a scissor support assembly (16).

Abstract: A sprung seat having an L-shaped base arrangement includes a spring means for adjusting the springing characteristic of the seat as desired. For that purpose the seat has a two-armed pivot lever mounted pivotably about a central horizontal mounting axis on a back portion of the L-shape, in an at least approximately horizontal position. One arm of the pivot lever is connected to one end of at least one at least approximately horizontal tension spring of the spring means. The second end part of the tension spring is fixed to a fixing portion of a support lever. The fixing portion is at least approximately aligned with the mounting axis about which the armed pivot lever is pivotable. The support lever is pivotably mounted to the back portion of the L-shape and is connected by its fixing portion to a member of the scissor support assembly.

Abstract: A sprung seat frame for a seat comprises a seat plate for carrying for example upholstery and a base plate for mounting the seat for example on a motor vehicle floor. A scissor-type lever assembly comprising first and second levers which cross and are pivotally connected together is operatively disposed between the seat plate and the base plate. A seat frame springing system includes a compression spring disposed between the lever assembly and the base plate. To produce a softer spring characteristic than would otherwise correspond to the spring characteristic of the compression spring, the seat frame includes a correction spring which is operatively arranged between the two levers at least approximately parallel to the seat and base plates so that upon sprung downward movement of the seat plate the correction spring moves from a position above the pivotal interconnection of the levers to a position beneath the interconnection.