| 摘要 |
<p>A surface access closure assembly (10) comprises a rigid frame (16) defining the periphery of an aperture; and a rigid cover (11, figure 1) with a closed position in which the cover occupies the aperture and is located so as to protrude no further than an edge of the frame; and an advanced position in which the cover protrudes beyond the edge. The cover in the advanced position also is displaceable to an open position in which it is outside the line of the periphery; and the frame and the cover are connected together by a linkage (28) permitting movement between the closed and open positions of the cover via the advanced position. The linkage may include a hinge member (29), (31) and a slide member (32) which may be captive relative to the frame.</p> |
