| 主权项 |
1. A speculum for opening a vaginal cavity comprising:
a plurality of primary blades extending along a longitudinal axis from a proximal end to a distal end, each primary blade comprising a convex outer surface, wherein the primary blades define at least upper and lower blades that are pivotally attached and movable relative to each other between opened and closed positions for opening and closing in a first direction, and at least one supplementary blade extending along a longitudinal axis from a proximal end to a distal end, said at least one supplementary blade is fastened to a side of the speculum and configured to lie against a side wall of a vaginal cavity when in use, said at least one supplementary blade comprising: a concave inner surface situated between the proximal and distal ends of the at least one supplementary blade, an anchor portion at said proximal end of the at least one supplementary blade comprising a fastener, for fastening the at least one supplementary blade to the side of the speculum and a blade portion comprising a contact area disposed on the concave inner surface, wherein the blade portion is movable with respect to the anchor portion and the blade portion is shaped to interact with at least one of the primary blades to move into an extended position through interaction with the convex outer surface of at least one of the primary blades; and a hinge portion that joins the blade portion to the anchor portion to allow lateral movement of the blade portion relative to the anchor portions, wherein the concave inner surface is shaped to lie against the convex outer surface of one or more of the primary blades, wherein, when the primary blades are in the closed position, the contact area of the supplementary blade contacts the convex outer surface of at least one of the plurality of primary blades, such that a distal region of the supplementary blade lies close to or in contact with the primary blades when the primary blades are in the closed position, and wherein the contact area between the supplementary blade and the primary blade moves from the distal region of the supplementary blade to a proximal region towards the anchor portion of the supplementary blade as the primary blades are opened, such that the proximal movement of the contact area drives the supplementary blade to splay laterally in a second direction perpendicular to the first direction of the opening movement of the primary blades and thereby moves the supplementary blade into the extended position in response to opening of the primary blades, and wherein the at least one supplementary blade is resilient to return to a retracted position when the primary blades close, such that the distal region of the at least one supplementary blade lies close to or in contact with the convex outer surface of the primary blades. |
