摘要:
Embodiments of the invention include an optical fiber preform assembly and a method for making optical fiber using the preform assembly. The assembly includes a preform core rod, at least one overclad tube formed around the preform core rod, a handle attached to one end of the overclad tube, and a refractory material positioned in the overclad tube between the preform core rod and the handle. The refractory material reduces if not prevents movement of the preform core rod into the handle during the fiber draw process. Preferably, the refractory material is made of, e.g., magnesium oxide and/or aluminum oxide, and has a melting point, e.g., greater than approximately 2000 degrees Celsius. Embodiments of the invention also include a method for making optical fiber using this preform assembly.
摘要:
A free flyable structure includes a wing formation (2) including an inflatable container of such form that when it is inflated the container (2) has an aerofoil shaped cross-section whereby relative displacement between the container and surrounding air enables free flight conditions. A substantially rigid means (19) carries the pay load from the wing formation (2). Flight path control of the flyable structure includes producing relative displacement between the load and wing formation. Additional flight path controls may be used. A canard wing assembly (82) is suggested. The structure is power driven and in the disclosure a power unit (85) having a propeller (86) is proposed.
摘要:
An airfoil structure including an elongate hollow container which, in use provides an airfoil cross-section between the longer edge regions of the container. A space is provided for so stiffening the leading edge region, that when the structure is in use the end regions of the container are permitted to deform out of the plane of the remainder of the width of the container - while this remaining part of the container width is kept substantially undeformed.
摘要:
An aerofoil structure which is inflatable by ram air when in use, includes a flexible multi-cell air fillable envelope having a readily removable flexible spar at its leading edge whose ends provide anchorages for a pair of operator control lines. In use the spar flexs to accommodate variations in air speed over the envelope.