Improved method and means for controlling the fire of guns on aircraft

摘要

461,824. Controlling fire of guns on aircraft. NORTH, J. D. Sept. 10, 1935, No. 25119. [Classes 92 (i) and 92 (ii)] Relates to means for controlling the fire of an aircraft gun 1, Fig. 1, movable in elevation and azimuth, as for example on a ring mounting 4, so that firing is prevented when a part of the structure of the aircraft is in the line of fire, said means including as part of the firing circuit a screen member 11, Fig. 2, bearing on its surface a representation of the danger field 17 and a contact member 16 moving in elevation and training with the gun to be controlled, the firing being prevented when the contact member bears on the danger surface. According to the invention, the screen member is of cylindrical form and one of the gun movements, for example the training movement, is represented by a rotation of the contact member relatively to the screen, the other movement, for example the elevating movement, being represented by a linear movement of the contact member parallel to the axis of its rotation. In the form shown in Figs. 1 and 2, the contact 16 is carried by a cross-bar 14 which rotates in training with the ring 4, and is connected by links 12 with the elevating arm 2 to produce the required linear movement. In the form shown in Fig. 3, the contact member 27 is carried by the rotary ring 4 of the gun mounting, and has a linear movement in the slot 26 effected by a spring-controlled bell-crank lever 21 and a cable 18 connected with the elevating arm 2 supporting the gun. The contact member bears against a fixed cylindrical ring not shown, which bears the shaped danger field. The screen is generally formed of conducting material, the danger areas being represented by insulated insets, but the invention includes the use of raised or depressed danger areas when mechanical firing systems are used. Fig. 7 shows a pneumatic servomotor 58 for pulling the trigger 55 under the control of a rotary valve 61. The valve is shown in the firing position with a pressure port 60 and an exhaust port 64. To preclude firing under danger conditions, the screen 11 has a conducting surface corresponding to the danger area and the contact 16 is included in the circuit of a solenoid 53 which acts to open a release valve 65 and enable a spring 59 to move the trigger to inoperative position irrespective of the position of the firing valve 61.