Patent GB-343011-A (GB)
Abstract: 343,011. Gunnery calculators. AKT.- GES. C. P. GOERZ OPTISCHE ANSTALT, Bratislava, Czecho-Slovakia. Nov. 7, 1929, No. 34037. Convention date, Nov. 16, 1928. [Class 106 (i).] The data for laying a gun particularly for firing at a moving target is determined by means of a system of members arranged to form a pair of similar triangles with the sides located in two intersecting lines and with a common apex and adjusted in accordance with the range and functions of the angle of sight. Using the range and angle of sight as polar co-ordinates the Specification states that the practice table curves are approximately hyperbolas so that the data sought can be obtained mechanically as shown in Fig. 1 from the formula. y = a z/b--z where z is the range and a, b are quantities determined from the practice tables. Various forms of apparatus embodying the underlying principle of Fig. 1 are described for determining the fuze setting, target movement, tangent elevation, and angle of lead. For determining the fuze setting a baseplate 9, Fig. 2, has secured thereto a bearing 10 and guide frame 12 for a screwed spindle 11 carrying a nut 32 to which is pivoted a sleeve 33 slidable on a lever 1. The lever 1 is pivoted at D to a rod 17 slidable in a frame 13 which is itself slidable on the bearing 10. The other end of the lever 1 passes through a sleeve 34 connected to a block 35 movable in the guide frame 12. The frame 13 carries a roller 16 which is pressed by means of a spring 14 against a cam 15 and the rod 17, through an intermediate slidable member 21, is pressed by means of a spring 18 into contact with a cam 19. The cams 15, 19 are operatively connected with a shaft 30 which can be adjusted manually or automatically from the gun in accordance with the angle of sight. The screwed spindle 11 is adjusted according to the range by the operation of a device 36. The resulting movement of the block 35 may be transmitted by a cord 37 to an indicating device. For determining the displacement of the target during the time of flight t a single cam body 42, Figs. 3 and 4, rotatable and slidable on its shaft 43 may be provided the rod 39 substituted for the rod 17 being adjustable in the frame 13 by a screw 40 in accordance with the speed of the target. In a modification, Fig. 5, when a component of the target's speed is involved a second set of members is employed comprising a. shaft 57, a rod 50, inter-connected sleeves 56, 51, and a sleeve 52 pivotally connected to a sliding block 53 moved through the medium of a crank arm 55. When the arm 55 is set to the angle which the direction of target movement makes with the line of sight and the sleeve 56 is adjusted on the shaft 57 in accordance with the speed of the target the distance of the pivot 61 from the axis of the shaft 57 is a measure of the component of the target displacement. The pivot 61 is carried on a rod 60 slidable in the frame 13 and by adjustment in the manner described sets the lever 1 according to the displacement. The shaft 11 as shown is rotatably and slidably adjustable in accordance with the range and angle of sight. For finding the tangent elevation the mechanism as shown in Fig. 6 is employed ; in this arrangement the lower mechanism is utilized to set up a corrected angle of sight, viz. alpha2 which is equal to 90‹ (a-a0)/90‹-a0 the maximum and minimum values for the tangent elevation and being obtained when a = a0 and alpha = 90‹ respectively. The sleeve 74 is positioned by a cam 73 rotated in accordance with the distance z of the point of impact and the slide 76 is adjusted to the distance r (90‹-alpha) where r is the radius of the toothed wheel 80. The wheel 80 gears. with a rack on the frame 69 and is rotated by the movement of the sleeve 78 by an amount equal to ¢ (90‹-alpha) alpha0/90‹-alpha0‹. The wheel 80 is attached to the planet wheel of a differential gear, Fig. 7, the wheel 83 of which receives a movement equal to the uncorrected angle of sight so as to impart a movement to the wheel 84 equal to the corrected angle. This movement is transmitted to the arm 65 of the upper mechanism to adjust the block 67. The nut 32 is then adjusted to the value z and the angle of tangent elevation and read off on the block 68. A simplified construction for determining the tangent elevation and quadrant elevation is shown in Fig. 8, the rod 1 and screwed spindle 11 being attached to the opposite ends of a member 85 to which is also attached a rod 87 the rods and spindle being interconnected by a nut 32 and sleeves 33, 34. To determine the lead angle the arrangement shown in Fig. 3 may be employed but with the frames 12, 13, rotatably mounted so as to be set parallel to the direction of movement of the target and the spindle parallel to the direction of the hitting point. The angle between the rod 1 and spindle 11 is a measure of the lead angle. In the case of small angles an apparatus as shown in Fig. 9 is utilized consisting of a frame 88 with a pointer 93 moved by a screwed spindle 94, an arm 89, and a cord 97 which is secured at one end to the arm 89 and passes through an eyelet 92 around a roller 98 to the end 99 of a drum 100 provided with a curved line 101 representing the target distance x as a function of the distance z of the point of impact and the length u of the string between the points 96, 91.