251,399. Davis, H. March 16, 1925. Lifesaving chambers; buoys. - In lifesaving apparatus for submarine vessels of the kind comprising a detachable buoy for conveying the crew to the surface housed in a chamber in the submarine, means are provided for opening and closing the upper part of the chamber containing the buoy from within the latter as well as from within the submarine. Such means may comprise a door sliding in guides and operated by a screw. The buoy is as usual connected to a cable wound on a winch in the submarine for the purpose of drawing the buoy down again, and a second cable connected to the submarine at its lower end is adapted to be connected at the other end to a salvage vessel to serve as a guide for the buoy. The buoy c, Fig. 1, is housed in a chamber b in the hull of the submarine. Man-holes d, e are provided in the lower parts of the chamber b and buoy c respectively, and the covers of the manholes are adapted to be secured from either side by means of two separate sets of bolts. The buoy c is also provided with a hinged door e<2> and with one or more windows e'. The chamber b is closed at the top by a door g sliding in guides i and operated by a screw h which engages a nut h<1> on the door and is rotated by a handwheel j through a chain k<2>. The wheel j is mounted on a shaft j<1> which can be rotated from within the buoy c by means of a screwed spindle t which when rotated by the hand-wheel t<2> is projected from its bearing t<1> into engagement with the end of the shaft j<1> which passes through a bearing u in the wall of the chamber b. The chamber b may be flooded by means of a pipe k<3> and a valve k<4> operated from within the submarine by means of a hand-wheel, or from within the buoy by means of a screwed spindle v adapted to be projected into engagement with a spindle v<3> which operates the valve k<4> through gearing. Means such as screw bolts l, preferably having pointed ends adapted to be projected into recesses in the walls of the chamber b, are provided for locking the buoy in position. The buoy c rests, preferably on a ring of balls x<1>, on a false bottom in the chamber b. This false bottom is perforated at b<o>, and below it are arranged winding drums p, w<1>. The drum p carries a cable q permanently secured to the buoy c which serves to draw the buoy down to the submarine by means of winding gear operated from within the vessel. To guide the buoy in its return, a second cable w passes through a guide tube w<2> in the buoy and is provided with a ring w<3> or the like at its upper end by means of which it is made fast to the salvage vessel after the buoy has risen to the surface, so that during subsequent operations the buoy slides on the cable w. Balls x housed in the walls of the chamber b facilitate the re-entry of the buoy into the chamber. The buoy carries ballast c<2> at the lower end, and may also be ballasted at one side near the top to prevent it from rotating on the cable w when the latter is in an inclined position. Alternatively, a metal pin may be housed in a recess in the wall of the buoy and pivoted so as to project therefrom when the buoy rises from the chamber b. The chamber b is emptied of water by means of a valve n after the buoy has been drawn into position and the door g shut. To enable the buoy c to be flooded when on the surface to facilitate its descent, a cock c<3>, operated by a hand-wheel c<o> outside the buoy, is opened, and to drain the buoy when in position in the chamber b a cock c<4>, which is accessible when the cover d is opened, is provided. This cock is in the form of a plug screwing into a casing c<5>, Fig. 8, and normally closes the opening c‹ in the wall of the buoy, but on being screwed back by means of a key engaging a squared recess therein uncovers a port c<7> which allows the water to drain out, and a port c<8> which allows air to enter the buoy by means of a pipe c<9>.