Innerspring construction with springs having free terminal convolutions

An innerspring comprising:

• a plurality of helical springs each formed of a plurality of coil turns, said springs being organized into an array and defining a support surface to said innerspring,
• means for interconnecting said springs into said array,
• each said spring being made in a continuous piece having a terminal convolution at each end of a generally helical body portion of said coil turns, and first and second offset segments formed on opposite sides of an attachment convolution at each end of said body portion and spaced from a respective terminal convolution which extends from each attachment convolution, said first and second offset segments having generally straight portions which are laterally outboard from a cylindrical shape generally defined by the coil turns of said body portion, said first and second offset segments being located in substantially the same plane which is generally perpendicular to a longitudinal axis of said body portion, a generally straight third offset segment between said first and second offset segments and generally tangential to said body portion, said terminal convolution having a radial extent from the longitudinal axis of said body portion such that a portion of the terminal convolution overlaps and contacts the third offset segment when the terminal convolution is compressed relative to said portion along a longitudinal axis of said body portion.

A mattress innerspring comprising:

• a plurality of helical springs each formed of a plurality of coil turns, said springs being organized into an array of orthogonal rows and columns and defining support surfaces to said innerspring on top and bottom sides thereof,
• means for connecting adjacent springs one to another in said array,
• each said spring having an attachment convolution and a terminal convolution at each end of a generally cylindrical body portion, with first and second offset segments in each attachment convolution at each end of said body portion and spaced from a respective terminal convolution, said offset segments being on opposite sides of said body portion and having generally straight portions which are laterally outboard from the generally cylindrical shape of said body portion, said first and second offset segments connected by a generally straight third offset segment which overlaps a turn of said body portion, said offset segments being located in substantially the same plane which is normal to a longitudinal axis of said cylindrical shape, said first and second offset segments being closely adjacent in pairs in the array and adapted for engagement with said means for interconnecting said springs in the innerspring, such that each said respective terminal convolution remains free of said interconnecting means when said spring is in the innerspring assembly, and said terminal convolution has a diameter of at least as wide as a diameter of said coil turns of said body portion such that said terminal convolution overlaps and contacts said third offset segment of a respective coil when compressed on to said body portion along the longitudinal axis of the coil.

A mattress innerspring comprising:

• a plurality of helical springs organized into an array of orthogonal rows and columns, each said spring being formed from a plurality of coil turns defining a generally helical compressible body portion and a terminal convolution at an end of said body portion, said body portion including an attachment convolution adapted for engagement with means for interconnecting a plurality of said springs in said innerspring assembly, said attachment convolution being spaced from said terminal convolution such that said terminal convolution remains free of said interconnecting means, said attachment convolution having first and second offset portions located on opposite sides of said attachment convolution and laterally outboard from a cylindrical shape defined by the coil turns of said body portion, and a generally straight third offset portion connecting the first and second offset portions, at least a portion of said terminal convolution axially aligned with said third offset portion of said attachment convolution such that said terminal convolution overlaps and contacts said third offset portion of said attachment convolution when said terminal convolution is fully compressed upon said attachment convolution along a longitudinal axis of the innerspring, and
• means for interconnecting a plurality of said springs in said innerspring assembly, said interconnecting means adapted to connect the first and second offset portions of said attachment convolutions of adjacent springs in the array.