33results about How to "Act as a secondary seal" patented technology

The invention belongs to the technical field of shield construction, and particularly relates to a novel shield launching and receiving tunnel portal pressure-regulating self-sealing structure. The problems that in the prior art, a sealing structure is not thorough in sealing, and water and slurry are prone to leaking when the pressure of the water and the slurry is large are solved. According tothe technical scheme, the novel shield launching and receiving tunnel portal pressure-regulating self-sealing structure comprises an embedded annular plate and a fixed annular plate, the section of the embedded annular plate is in an L shape, one side of the embedded annular plate is perpendicular to the axis of a shield tunneling machine, the other side of the embedded annular plate is parallel to a shell of the shield tunneling machine, and a steel edge wrapping type rubber cord fabric is arranged on the side, perpendicular to the axis of the shield tunneling machine, of the embedded annularplate; and the steel edge wrapping type rubber cord fabric is located between the embedded annular plate and the fixed annular plate and is fixed through a fastening bolt, the fixed annular plate isconnected with a folding turning plate, and a compression type self-sealing structure is arranged at the inner side of the embedded annular plate. According to the novel shield launching and receivingtunnel portal pressure-regulating self-sealing structure, a double-layer self-sealing structure and a middle resistance type compression spring are adopted for sealing, so that the problem that a tunnel portal rubber cord fabric is difficult to seal can be effectively solved, and the novel shield launching and receiving tunnel portal pressure-regulating self-sealing structure is suitable for sealing a shield launching and receiving tunnel portal.

The invention relates to a small rescue unmanned aerial vehicle which is used in cooperation with a rescue helicopter or a ship. The small rescue unmanned aerial vehicle comprises an unmanned aerial vehicle body, an inflation device, a life buoy, a life buoy storage device and a bobbin, wherein the life buoy storage device is an annular container with a storage groove at the bottom; the inflationdevice is provided with an inflation needle; the inflation needle is arranged at the top of the inner side of the life buoy storage device; the life buoy is arranged in the storage groove in a foldingmode; the life buoy comprises a life buoy body and an air nozzle, and the inflation needle is inserted into the air nozzle; the bobbin can be rotationally and horizontally fixed on the inner ring ofthe life buoy storage device; and a traction rope is arranged on the bobbin, and one end of the traction rope is tied on the life buoy. According to the small rescue unmanned aerial vehicle, the smallor micro unmanned aerial vehicle with low price serves as a carrier, the search and rescue cost is greatly reduced, the search and rescue visual field is wide, the searching range is large, and the mode is superior to a search and rescue mode of throwing or casting a large number of life-saving equipment in a certain area; the search and rescue personnel do not need to go deep and rescue, and thesafety of the search and rescue personnel is improved.