Patent GB-129285-A (GB)
Title: Improvements in and relating to Automatically Operated Indicators of Targets.
IPC: F41J5/04
Filed: 1919-07-02
Abstract: 129,285. Cibles Automatiques Michoud, Soc. Anon, (Assignees of Michoud, A., and Carbonnier, L.). July 5, 1918, [Convention date]. Multiple-indication apparatus.-An automatically-operated indicator or dummy target exhibiting to the marksman the location of shots on a distant target, has a marking member operated by electro-magnets and mechanism controlled by at least two connexions in a circuit having contacts on the distant target. The marking-member shows the particular sector of concentric circles and the radial distance. Two forms of indicators are shown for targets with four sectors and five concentric circles. In the first formshown in Figs. 1 and 2, a pointer 11<1> is moved over a small target 5 by a sliding motion in forks 10<1>, 10<2> on a disk 10 secured to a hollow shaft 6. The shaft and disk are rotated bv an endless chain 9, and the sliding motion of the pointer is effected by a chain 14 which passes through the shaft 6 and pulls against a spring 12. The chains 14, 9 are operated by arms 17, 19 which are pressed upwards by springs 21, 22 and have bent ends 17<1>, 19<1> bearing against two groups of hammer bars 23. Balls 24 engage notches 23<1> in the bars and are held in position in the plate 1 by suspended plates 25, controlled by pawls 26 which form armatures of electro-magnets 28. When a current passes, a pawl 26 of each group is depressed clear of its plate 25, the balls are pushed aside by the weight of the bars 23, and the arms 17, 19 are turned to an extent corresponding to the drop of the bars 23 permitted by the stepped stop 29. To bring the indicator back to zero, a shaft 31 is turned by a crank 30, and cams 33 on the shaft 31 lift the arms 17, 19 and hammer bars 23 so that the pawls 26 again lock the the plates 25, when the balls have entered the notches in the bars. The main target 34, Figs. 4, 6, and 7, comprises separate concentric sections spaced by elastic washers 39 from the front plate 35 of a frame, and two cross-plates 37, 38. Bolts 40 provided also with elastic washers 41 touch balls 43 carried by balance levers 45, Fig. 8, in troughs 44 which are tilted with the whole frame by adjusting screws 49. The levers 45 make contact by pins 50 with pairs of insulated metallic strips 51, one strip for the circuit controlling the radial motion of the indicator pointer, and the other for the sector circuit. The balls are retained in the troughs by plates 53. Fig. 5 shows a diagram of the electric circuits. The four electro-magnets I, II. III, IV control the circular movement of the pointer, and the five electro-magnets 1 to 5, control the radial movement. An interrupter Z breaks the circuit as soon as the lever 17 drops, the contact piece of the lever being adjustable so that the interruption may be simultaneous with the first movement of the lever or be delaved. In the second form of indicator, Fig. 11, eight sectors and ten concentric segments are provided. The general anangement is the same as in the first form, but the electric connexions are modified as shown in Fig. 13. The main target has ten recoiling balls in each alternate sector, and in the indicator there are six hammer bars corresponding to the odd circles 1, 3, 5, 7, 9 and the bull's eye circle 10, and four hammer bars for the sectors II, IV, VI, VIII. For example, a, b, Fig. 13, represent the terminals of circle 3. If a hit occurs on this circle, the balance lever completes the circuit between these terminals. If a hit occurs near sector VI on circle 2, the lever completes the circuit between contacts 51<1> and 51<2>, and will energize the electro-magnets 1 and 3 for the circles and electro-magnet VI for the sector. If, however, the bullet strikes on circle 2 between sectors IV and VI, electro-magnet IV will also be energized. To indicate the difference between two such shots, the hammer bars are checked in their fall by the device shown in Fig. 14 and comprising a chamber enclosing balls 55 and slotted hammer bars 23, and of a width equal to the combined thickness of one bar and three balls. When one bar has dropped to bring its solid part across the chamber, the remainder are therefore locked and cannot fall. The drop is limited to half the height between two steps of the stops 29 under the levers 17, 19. To mark the sectors and circles intermediate between those represented by each hammer bar, two bars of two adjacent sectors and circles have always to be dropped, but one has a longer slot than the other and continues to fall after the first has crossed the chamber, until checked by the balls 55. The fall of the second bar determines the movement of the pointer. Figs. 16 and 30 show the positions of the hammer bars to indicate a hit on circle 2 near sector VI. and Figs. 16 and 29 those for a hit on circle 2 and. sector V.