Patent GB-553951-A (GB)
Title: Improvements in or relating to dummy or imitation firearms for field training purposes
IPC: F41A33/00
Filed: 1941-09-09
Abstract: 553,951. Teaching warfare. PALMER, V. F., and HOLT, G. G. Sept. 9,1941,No. 11529. [Class 119] A dummy machine gun for use in the tactical training of troops in the field comprises means for simulating the noise made by a machine gun and directing the noise towards the troops fired at, and means for so projecting a divergent beam or flash of light (simultaneously with or slightly after firing) that the beam or flash is visible to such troops. The whole gun may be a dummy, or an attachment producing the noise and light may be attached to or may replace the barrel of a real machine gun. The Figures show a dummy Lewis gun comprising a vertical spindle 22 which is rotated by a coiled spring 25 contained in a non-rotatable drum 24. On the spindle 22 is a disc 34 from which depend three flange-like cams 35 which engage a roller 40 mounted on one end of a strong spring arm 36 the other end of which is anchored to a flange 11. When the roller 40 is released by a cam 35 a hammer 37 on the spring arm strikes a diaphragm 12 and the sound issues from (and is amplified by) a barrel 9. The light-projecting means includes a tube 13 containing an electrical battery and bulb, a fixed contactl6 and a spring contact 15. When the trigger 6 is pulled, the contact 15-16 is made. Means for interrupting the light beam, to simulate a flash for each shot, comprises a perforated rotary shutter 18 which is rotated, via a flexible shaft 19, by a rubberedged roller 31 in contact with a disc 27 fixed on the spindle 22. Rotation of the disc 27 and spindle 22 is controlled by a resilient block 30 secured to the end of a slide 17 connected with the trigger, this block abutting one of three pins 28 extending from the disc. To fire one shot, the trigger is pulled and immediately released, whereupon the spindle 22 rotates through 120 degrees and is stopped by the impact of the next pin 28 upon the block 30. For rapid fire, the trigger is held back and the disc 27 revolves without hindrance. Means are provided for cocking the device. In the uncocked position, a detent 65 on a spring (64)-urged lever 62 pivoted at 63 engages the teeth of a ratchet wheel 66 fixed on the spindle 22. To cock the device, a bolt 54, backed by a spring 67, a slide 57 and another spring 68, is pulled back, with the result that an arm 60 extending from the slide 57 pulls counter-clockwise the lever 62, thus releasing the ratchet wheel 66. The bolt 54 is held in the cocked position by he engagement of a notch 56 therein with a detent 70 on one end of a lever 71 pivoted at 69, the other end being spring pressed at 72. To simulate firing period representing the number of cartridges contained in the usual drum, the detent 70 is released after a certain number of revolutions of the spindle 22. This release is effected by cam elements 52 secured to an endless band 50 driven from the spindle 22, the elements rocking the lever 71 clockwise. Means for braking the spindle 22 may comprise an air brake, an escapement, or arms 41 on the disc 34, which arms, as the spindle revolves, strike one arm 42 of a two-armed lever pivoted upon a spindle 42a. The other arm 44 is a spring strip 44 having a striker 45 which beats against a hard surface 46. The spring 25 may be wound up by means of a handle 460. Suitable glass may colour the light. The interior of the tube 13 may be non-reflecting.