Abstract: A box spring assembly includes a base frame, a top wire grid and a plurality of sinous wire springs interconnecting the top wire grid and the base frame. The sinuous wire springs each comprises a sinuous wire strip formed into an inverted U-shaped configuration with the closed end of each U-shaped spring attached to the top wire grid by a snap-fit connection and the free ends at the bottom of the U-shaped spring being attached to the base frame.

Abstract: A collapsible bedding foundation comprises a rectangular base frame and a rectangular wire grid. The wire grid is hingedly supported upon the frame for movement between a collapsed position and an erect position. The hinged connection between the wire grid and the base frame is achieved by a plurality of transverse spaced, parallel planar support elements pivotally connected to the base frame and the wire grid. The foundation is supported in an erect position solely by a pair of longitudinally extending, parallel planar support elements pivotally connected to the longitudinal edge of the wire grid and, when the foundation is erect, fixedly secured to the base frame.

Abstract: A bedding foundation box spring having novel double twist coil springs interconnecting a wooden base frame and a top wire grid. The coil springs each comprise a single length of wire having a middle section located in a diametral plane of one end convolution of the spring and a pair of spring arms coiled in the same rotational direction from opposite ends of the middle section. Each of the spring arms is formed into a helix of varying pitch which terminates in a free end of the spring arm. The free ends of the two spring arms of each coil are located on opposite sides of the end convolution of the coil and are secured to the wire grid. The novel coils are manufactured by inserting a straight length of wire through a stationary pair of forming dies and a mandrel located between the dies. With the middle of the straight length of wire located in the mandrel, the mandrel is then simultaneously rotated and moved axially while the ends of the length of wire are pulled through the stationary forming dies.

Abstract: A bedding foundation box spring having novel double twist coil springs interconnecting a wooden base frame and a top wire grid. The coil springs each comprise a single length of wire having a middle section located in a diametral plane of one end convolution of the spring and a pair of spring arms coiled in the same rotational direction from opposite ends of the middle section. Each of the spring arms is formed into a helix of varying pitch which terminates in a free end of the spring arm. The free ends of the two spring arms of each coil are located on opposite sides of the end convolution of the coil and are secured to the wire grid. The novel coils are manufactured by inserting a straight length of wire through a stationary pair of forming dies and a mandrel located between the dies. With the middle of the straight length of wire located in the mandrel, the mandrel is then simultaneously rotated and moved axially while the ends of the length of wire are pulled through the stationary forming dies.