| 摘要 |
<p>1494488 Amusement and exercising apparatus F REBAJES 4 Dec 1974 [26 Dec 1973] 52547/74 Heading A6M [Also in Division B6] A shape-retaining flexible geometric structure for exercising and amusement purposes consists of a structural form 60 (Figs. 9 and 10) comprising a double-sided continuous curved strip having substantially; uniform resiliency, each side having four points of inflection 66 providing four surface portions having successive concave and convex contours 68 and 70, the shape being retained by the intrinsic balance of elastic stresses so that the strip is capable of retaining the shape of the form in an infinite number of positions of translation of any arbitrarily selected region of the strip along a path outlined by the shape of the form. "Uniform resiliently" means that the strip has substantially the same elastic properties throughout its length. The form may be constructed from two open ended annular strips 12 and 32 (Fig. 4) having upper surfaces 14 and 34, and lower surfaces 16 and 36, made of resilient flexible material (e.g. cardboard, sheet metal or elastomeric plastics sheet). The strips are concentrically disposed one on top of the other, and one end portion 20 of the strip 32 is connected to 'an end portion 42. of the other strip 12 (e.g. with adhesive or screws and wing nuts 52), to form a joint 50. The combined strip is then extended along its axis of symmetry to form a helix (Fig. 3). A free end portion 22 or 40 is bent in such a way that it is disposed adjacent to the other free end portion 40 or 22 with the original lower surfaces 16' and 36' (Fig. 5) facing each other. The end portions 40 and 22 are then bent inwardly and brought towards each other to align the lower surfaces 16' and 36' into a common plane, and the ends are then-joined together to give the required structural form. The form may be modified by forming slits or triangular projections along the inner or outer edges of the strip, or by providing projections or legs at points on the external edge so that the structure can stand on a flat surface. The internal opening of the form can be other than circular and may be asymmetrically disposed.</p> |
