Mattress spring structure with reinforcing frame in the lumbar area

In a mattress spring structure,

• a plurality of coil springs arrayed in longitudinal and transverse rows of such coil springs between upper and lower margins and opposite side margins of said spring structure, with the coils in each row aligned with the others in each said row, the structure including a border piece which defines the said upper, lower and side margins,
• means securing each coil spring of each transverse row in paired joinder to a coil spring of an adjacent transverse row, a central area of the spring structure being defined by a selected succession of transverse rows of coil springs,
• a strengthening frame member receivable exteriorly against and encircling a major expanse of the spring structure central area, the frame member comprising
• a first transverse frame segment extending along a juncture of the coil springs of a transverse row first in selected succession of such with an extra succession transverse row adjacent thereto, there being joining members closely joining together said first transverse segment and each joined pair of coil springs in the said first succession transverse row and the extra succession transverse row adjacent thereto,
• a second transverse frame segment extending along a juncture of the coil springs of a transverse row last in the selected succession of such with an extra succession transverse row adjacent thereto, there being joining members closely joining together said second transverse segment and each joined pair of coil springs in the last transverse row and the extra succession transverse row adjacent thereto, and
• a pair of longitudinal frame segments spaced inwardly from the spring structure side margins and extending longitudinally in between adjacent longitudinal rows of coil springs, opposite ends of the transverse frame members being connected to opposite ends of the longitudinal frame members, there being joining members, closely joining together said longitudinal frame segments and successive ones of pairs of coil springs comprised each of a coil spring in one of the adjacent longitudinal rows and a coil spring in the other of the adjacent longitudinal rows.