GUN, PNEUNATIC. The improved pneumatic ordnance designed by John Ilapieff is adapted to the firing of projectiles containing high explosives. It consists, as shown in Figs. 1,2, and 3, of a gun-barrel A that is provided from its breech to a point beyond the trunnions with a surrounding jacket B, connected by openings with the breech-end of the barrel, thus forming an annular space or reservoir C around the barrel for the passage of the fluid press ure to the breech. The barrel and jacket are secured together to form a rigid structure, thus the jacket carries the gun trunnions D, both hollow. and connected by balanced swing-joints E with fluid supply-pipes F that lead and branch from a fixed main central supply-pipe. the connection between the branches and the main pipe being also balanced, and a swing joint H.
The jacket is formed preferably of three or more sections—the trunnion section, an inter mediate section or sections, and the valve section—bolted together. The trunnion and inter mediate sections are supported from the barrel by radial webs or studs, leaving ample space for the free passage of the fluid from the trunnions to the breech. The breech-end of the bar rel contiguous to the main valve 4 is continued by an inner flanged bonnet a having lantern openings c for the admission of the fluid-pressure, and having radial and longitudinal pas sages to obtain efficient work of the valve. The valve section of the jacket is provided with ribs supporting an inner jacket, which, with the bonnet, forms a chamber for the main valve, from the back portion of which chamber through one of the ribs a passage is formed to the auxiliary valve. The forward part of the barrel, which is free of jacketing. is supported by a truss attached to the trunnion section of the jacket by bolls and keys. The barrel is supported on the truss by chairs which are adapted to transverse and vertical motion, so that the align ment of the barrel can he easily adjusted. The gun-carriage K, mounted to turn upon a suit able base. L, is formed in the main of sheet, angle, I, and channeled irons, braced and also tied together; the vertical sides, each formed by a pair of legs. are housed by sheet-metal and secured at their upper ends to inner and outer castings, forming- the, trunnion-bearings. The carriage carries the motors—elecU•ic, pneumatic, hydraulic, etc.—for training the gun and for elevating.
The gun-carriage is provided with locking wedges ri, 1y which the carriage, after each training movement, is securely held in its position upon the base. These wedges are operated
to release the carriage just. iii advance of I he movement of the motor to train the gun ; and in the preferred :n•raugcmiuit, t he fluid passing I 'trough passages in the head of the central supply-pipe (1, before passing to the motor, will first. flow to the cylinders M to operate the wedge-pistons and having raised them will then pass I o the motor to operate it. The ar rangement is also such that as soon as the carriage stops the fluid acts to return the wedges, to secure the carriage. The wedges thus prevent any local motion of the carriage with respect to its base, so that during the firing the base and the foundation are brought to gether to resist recoil.
The carriage is formed with front and rear hooks e to engage with flanges on the base, to reduce all lateral and vertical motions during recoil. The carriage, besides the platform to • operate the firing, training, and elevating mechanism automatically, is also provided with means for training it by hand from a special platform g, and with eyes and hooks for tackle training. The balanced swing-joints of the trunnions. and the branch supply-pipes with the main pipe. are in the main similarly constructed. They each consist of an inner pipe h (Fig.1), having radial passages, and an outer casing i having an annular passage, with which the radial passages communicate, so that both are constantly open, and the joint balanced by the press ure of the fluid, whatever the relation between the pipe and casing. The joint between the two is packed by suitable packing carried by a packing-carrying annulus k which surrounds the inner pipe, having openings corresponding to the radial passages in the pipe and supports both the packings 7, arranged upon opposite sides of the joint, whereby, upon the removal of the annulus, the packings are simultaneously bodily removed therewith, and without the necessity of disturbing, removing, or dismantling any other parts. These packings are spaced and supplied with a liquid for sealing, and if need be lubricating, the joint. To prevent the leakage of the fluid through the metal of the casing, which. being of cast metal, may be more or less porous, there is interposed between the carrying annulus and the casing a ring or lining, formed preferably of bronze or copper; and in addition to the packings carried by the annulus, the latter, and also the ring or lining, is stepped and sealed against packings, held on corresponding steps on the pipe and easing.