Patent GB-586113-A (GB)
Title: Improvements in and relating to turrets and mountings for guns and the like
IPC: F41A27/26
Filed: 1940-07-22
Abstract: 586,113. Gun mountings. NASH, A. G. FRAZER-. July 22, 1940, No. 25358/39. [Classes 92 (i) and 92 (ii)] Hydraulically-operated gun mountings of the ring type for use on aircraft or high-speed vehicles, comprises the following features in combination (1) a training motor 7, Fig. 1, attached to the rotary ring 2 and driving a pinion engaging a rack on the fixed ring, (2) a gunner's seat or support 25 on the rotary ring and a gun or guns 12 mounted on the rotary ring for elevation by a hydraulic ram 37, (3) a rotary joint 8 on the training axis for conveying pressure liquid to the motor and ram by way of control valves 14, 15, Fig. 4, in a single casing on the gun or on the rotating ring, the pressure feed being obtained by a pump in circuit with a recuperator, and (4) a master valve 17 in the control valve casing which normally provides for byepassing the liquid from pressure to exhaust, but, on being operated by gripping the valvecontrol handles 18, admits pressure liquid to the training motor and/or the elevation ram to move the gun in the same sense as the control handles are moved. In the form shown, the valve casing 11, Fig. 1, and control handles 18 are mounted on a cradle adjustably attached at 19 to a lever 20 moved about trunnions 21 on a frame 36 by a link connection 23 with an arm 24 pivoted to the frame at 35 and carrying the gunner's seat 25, the ram piston 40 being connected with the arm 24 by a link 41. Fig. 4 shows the arrangement of the valve cradle which supports the gun in straps 47 and the control handles assembly 49 on a pivot 48. The master valve 17 is movable in a casing above the elevation valve 14 and the training valve 15 is furnished with mechanism 80 precluding its operation under endangering conditions. When the control handles 50 are grasped, levers 51 are depressed to actuate the master valve by levers 55, shaft 59, lever 60 and link 61. Rocking the assembly 49 about the axis 52 acts through a link 63, arm 64, shaft 65, arm 67 and link 68 to move the elevating valve 14. The training valve 15 is operated through linkage 71, 73, 74 and the mechanism 80 by moving the handle assembly about the bearing 48. The link 74 acts through lever 78, knife-edge member 79 and fulcrum bar 82 on a slide 80 connected to the valve rod 83, and the arrangement is such that cams act, through linkage 86, 88 on the bar 82 to preclude operation of the valve under endangering - conditions. Fig. 7 shows the arrangement of. the piston valves and ports in the casing housing the master-valve 17 and the elevation valve 14. The master-valve is shown in normal closed position, the pressure port 108 being in communication with exhaust port 107 to provide for circulation of liquid in the system, a poppet valve 111 creating a hydraulic lock in the pipes leading to the rams operating the seat system. Movement of the master valve to the right opens the poppet valve to remove the pressure lock and connects pressure port 108 to port 114 and exhaust port 107 to port 115. The ports 114, 115 are associated with the elevation valve which is shown maintained in neutral position by springs 122, 123 and movement of the valve in either direction from this position controls the seat rams. The ports 114, 115 also connect with the training valve 15 which is of similar construction to the elevation valve 14. The joint 8 ensures in known manner the passage of the pressure liquid-from outside to the hydraulic systems in the turret and the exhaust therefrom not withstanding rotation of the turret, and electric brush contacts associated with the member 8 convey the electric power necessary for accessories within the turret. To maintain a low positive pressure in the pipe system leading to'the master valve at all times, even when the aeroplane is not in use, a recuperator unit 44 is provided comprising a spring-loaded piston acting on the liquid and a small pressure maintaining pump 178 actuated by hand or through a connection with the rocking arm 20. In a modification described with reference to Fig. 21 (not shown), the gun-sight is moved synchronously with the gun by the means described in Specification 538,642, [Group XXIV]