| 摘要 |
<p>A method of making a seating structure comprising a frame (86) and a membrane (14) supported on the frame under tension is disclosed. A pair of side frames (12), each define a front face (18), a rear face (20) which defines at least one open channel (24), and a curved outer edge portion(16) joining the front and rear faces, A sheet of membrane has a bead secured to each opposed side edge of the sheet by passing the membrane around the bead and stitching it to itself to form a tube. The PVC is a relatively rigid grade of PVC and is rectangular in cross-section. The bead is free to move along the tube. The beads are inserted in the open channels along the rear face of both side frames with the longer axis of the bead directed into the channel. Then the side frames (12) are moved apart on a hydraulic jig to tension the membrane. Tension in the membrane (14) does not cause the bead to come out from the open channel due to the relative length of the longer axis of the bead and the shape of the channel. Since tension tends to cause the bead to rotate about the outer edge of the opening of the channel (24), a protrusion (32) is define in the channel to resist such rotation. Because of the shape of the bead and channel, and the fact that tension applied to the bead tends to cause the bead to rotate rather than be pulled out in the direction of the applied tension, the bead can be a relatively loose fit in the channel. This allows for ease of insertion of the bead in the channel even where several layers of membrane are used and wrapped around the bead. Typically, the bead is heated before being inserted in the channel to allow it to deform sufficiently to match the contour of the side frame (12).</p> |
