Spring module

A spring module for disposition between a base frame and a grid frame for attachment, respectively, to the base frame and grid frame comprising an attaching element at the lower end, an attaching element at the upper end and resilient supporting elements yieldably connecting the attaching elements comprising vertically-disposed, spaced, parallel supports, each support comprising an arcuate length of wire located substantially midway between the upper and lower attaching elements, each defining a pair of diverging legs, said arcuate lengths of wire being disposed so as to face in opposite directions with respect to each other and upper and lower straight lengths of wire integrally connected at one end to the ends of the legs of the arcuate lengths of wire and at the other ends to the attaching elements, said upper and lower straight lengths of wire extending from the ends of the arcuate lengths of wire in directions opposite to the legs of the arcuate lengths of wire at acute angles thereto and being connected at their ends to the attaching element, said diverging legs of the arcuate lengths of wire being connected to the upper and lower straight lengths of wire by arcuate lengths of wire of smaller radius of curvature than the radius of curvature of the arcuate lengths of wire which connect the diverging legs and wherein said arcuate lengths of wire of smaller radius of curvature are located closer to the vertical axis of the module than are the arcuate lengths of wire of larger radius of curvature.