Patent GB-150358-A (GB)
Title: Improvements in instruments for determining the correct moment or point of release of a bomb or the like from aerostats or aeroplanes
IPC: F41G3/24
Filed: 1916-06-14
Abstract: 150,358. Houghton, A. B. June 14, 1916. Sights and methods of sighting.-Relates to instruments for determining the correct moment or point of release of a bomb from aircraft, and comprises an altitude scale and pointer for setting the predetermined altitude of the aircraft, chronometrical means adjusted automatically by the setting of altitude, means for indicating the direction and inclination of flight, and means for effecting or giving a signal for the release cf the bomb. A traversing foresight is maintained in alinement upon the target, the chronometrical device being started during the traverse and an electric-contact block being adjusted by the traverse for a time determined by the altitude setting, the subsequent traverse of the fore-sight bringing it into contact with the electric-contact block and thus releasing the bomb or giving a signal. In the construction shown in plan in Fig. 1 and in side elevation in Fig. 2, a cylinder 2 carries a helically-arranged altitude scale; rotation of the cylinder by means of a handle 4 adjusts an index 8 to the known height value, the index 8 being attached to a post 9, which carries the rear-sight 12 and is raised by a screw and nut geared to a toothed wheel at the base of the cylinder 2. The movement of the post 9 sets an electric contact 22<a> at the position, which corresponds to the height set, in the path of the seconds hand 23 of a stop-watch 24; this setting is effected by a cam-surface 16<a>, on a bar 16 carried by the post 9, acting through a lever 17 and -a link 20 connected to a bell-crank lever 22 carrying the contact 22a. The fore-sight is carried on a. sight-block 28 which is traversed to keep the sights on the target by a screw 29 operated by a handle 59. The first portion of the movement of the block 28 from the extreme right-hand end of the screw 29 sets and starts the watch-hand 23 by means of a. lever 41 in the path of the block 28. A contact-block 34 is dra.wn along a. track 35 by means of a ribbon 33 connected to the sight-block 28 until the ribbon is disconnected by the operation of a. trigger-device released by electro-magnetic means brought into operation upon contact of the watch-hand with the adjusted contact 22<a>. The subsequent traverse of the sight-block 28 while the sights are kept alined upon the target brings it into contact with the now stationary contact block 34 and completes the electric circuit for releasing the bomb, &c. A slot 13a in a plate 13 carried below the rear-sight 12 is used for preliminary sighting. The whole apparatus is mounted so as to be angularly adjustable upon a spindle fixed in the frame of the aircraft. Means for indicating the direction and inclination of the aircraft's flight are shown in Figs. 2, 5, and 6. The direction is determined by means of a pointer which forms the upper end of a counter-weighted oscillating lever 49 and moves over an upper central portion 48 of an opening 47 in a panel 46. The inclination of flight is indicated by means of a counterweighted drum 52 mounted on horizontal pivots in the opening 47 of the panel 46. During horizontal flight, a sector 52<a> of the drum obscures the opening 47; on deviation a clearance or space is seen at the top or bottom of the opening 47. These devices are observed through an opening 56 in a panel 57, Fig. 2.