A rocking chair comprises a base portion and a seat portion and includes a pair of C-springs for coupling the base portion to the seat portion. The C-springs flex to provide the seat portion with a desirably smooth and soft rocking motion while providing excellent structural integrity. Each C-spring has a contoured cross-sectional profile that provides a spring stiffness adapted to provide a smooth and comfortable rocking motion for a wide variety of body weights. The contoured cross-sectional profile also provides a high torsional resistance for minimizing lateral rocking movement of the seat portion.
1. A chair comprising a seat member, a base, and a coupling mechanism for coupling the seat member to the base, the coupling mechanism adapted for providing a smooth deflection when subjected to a load so as to facilitate a rocking motion of the seat member relative to the base, the coupling mechanism comprising:
at least two elongate members each having a substantially rectangular cross-section and first and second ends, each of said elongate members having an inner surface and an outer surface and each being formed with a channel extending longitudinally along said outer surface from the first end to the second end to create a thin center portion located between thicker side portions, each of said elongate members having an elongate, generally flat upper segment, an elongate, generally flat lower segment disposed generally below the upper segment, and a curved segment between the upper and lower segments, the curved segment curving at least 180 degrees and configured to flex when the first and second ends are moved relative to one another, the first ends of the elongate members being connected to the chair member, the second ends of the elongate members being connected to the base; and
a horizontal support coupled to said seconds ends of said elongate members, the horizontal support also being connected to the base;
wherein said horizontal support has a pair of mount portions, each mount portion comprising a recess having a contoured surface adapted to complement said outer surfaces of said elongate members so that an elongate member complementarily fits transversely across the mount portion.
2. The chair of claim 1 , further comprising a post extending downward from said horizontal support, said post adapted to be received by a cylindrical cavity for providing a swivel motion therebetween.
3. The chair of claim 1 , wherein the mount portions are arranged on the horizontal support so that the elongate members are spaced from one another and generally parallel to one another, and wherein the outer surfaces of the elongate members engage the mount portions in a manner to resist relative movement in a direction generally transverse to the longitudinal axis of the elongate members.
4. The chair of claim 1 , wherein the curved segment curves about a substantially constant radius of curvature.
5. The chair of claim 4 , wherein each of the elongate members have substantially the same cross-sectional profile from the first end to the second end.
6. A method of manufacturing a flexible coupling mechanism configured to resist lateral movement comprising:
providing at least two generally flat, elongate spring members each having a first and second end and first and second generally opposing sides, a channel extending along the surface of the first side substantially from the first end to the second end, the channel having substantially the same depth from the first end to the second end;
bending each of the elongate members to create a substantially flat, elongate upper section, a substantially flat, elongate lower section, and a curved section between the upper and lower sections, the curved section being bent at least about 180°;
providing an elongate connector comprising a pair of spaced apart mount surfaces, each mount surface having a recess that is contoured so as to be complementary to the channel of the corresponding elongate member in a direction generally transverse to the elongate connector;
attaching the lower sections of each bent elongate member to the connector so that the bent elongate members are spaced apart from one another and the channel of each elongate member complementarily engages the corresponding mount surface.
7. The method of claim 6 , wherein the elongate spring members have substantially the same cross-sectional profile along their entire length.
8. The method of claim 6 , additionally comprising forming an elongate slot in the upper section of each of the bent elongate members, wherein the elongate slot is generally parallel to a longitudinal axis of the corresponding elongate member.