Patent ID: 6983503

Claim:
A spring assembly for a mattress, in which an outermost coil spring of a spring array is secured in a space between upper and lower border wires and by pins, and helical coils are disposed in row directions on upper and lower portions of the spring array to knit an adjacent coil spring, such that each coil spring has a free terminal convolution protruded from an upper portion of the upper border wire and/or a lower portion of the lower border wire, the spring assembly comprising: an enclosure provided in the row direction on an upper end portion and/or a lower end portion of the coil spring for covering the terminal convolution from the adjoining border wire to the free end of the terminal convolution protruded therefrom, thereby interrupting interference between the terminal convolution and the upper and/or lower border wire and underlying coil spring and absorbing a lateral load applied to the terminal convolution.