Patent GB-145708-A (GB)
Title: Apparatus for tracing the routes of warships and merchant vessels
Filed: 1920-06-30
Abstract: 145,708. Baule, M. E. A. Feb. 26, 1919, [Convention date]. Course-recording apparatus.-Relates to apparatus for recording the course of a vessel which may he provided with means for tracing the course of a target vessel and for indicating the angle of sight for the launching of torpedoes. The course is marked, by means of a fixed training-device, on a card 7 which is moved by magnetic wheels 8, 9, driven by a card motor 17 rotating at a speed proportional to that of the vessel, the magnetic wheels being oriented in accordance with the ship's head. The North-South line of the card is kept on the fore-and-aft line of the vessel and is locked by magnetic balls 36, 37, during the interval in which a head motor 30 operates, to orient the wheels 8. 9, the card motor 17 and magnetic wheels 8, 9 being then out of action. A motor 38 continuously drives a screw-shaft 40 by electro-magnetic means at the left-hand end and is held in engagement till it reaches the right-hand end, where it is disengaged and returned by a counter-weight or spring. The cursor 41 drives a cursor 71 on a screw shaft 72. which in turn drives a currentdistributor 78 for the card motor 17 by means of a ratchet 79 whereby only the forward motion is operative. The shaft 72 can be displaced along a screw shaft 75 whereby the card motor 17 can be adjusted to the speed of the vessel. A clock periodically closes a switch 46 actuating a relay 45 to close contacts 44 which energize the cursor 41 through the contacts 42, 43, and also contacts 82 at the right-hand of a screw shaft 40, which energize the winding 81 of the magnetic wheels 8, 9, and a polarized winding 80 on the relay 45. At the end of the forward motion of the cursor 41 the contact 82 is broken, consequently the relay falls back and closes the contacts 84 whereby the winding 85 of the magnetic balls 36, 37 is energized and the head motor 30 is in a position to be supplied with current. An impulse motor 86 driven by the motor-compass carries a screw-shaft extension on which is a nut 88 in the form of a toothed wheel meshing with an elongated pinion 89 on the shaft of the head motor 30. The nut 88 hunts between the arms of a fork 91, but on a change of the ship's heading moves the fork and a contact thereon completes a circuit whereby the head motor 30 is energized and returns the nut 88 to its hunting position, the rotation of the motor being proportional to the change of heading, which is thus transmitted to - the mounting of the magnetic wheels 8, 9. The course of the target vessel is traced by a cursor 93 which is displaced by a distance motor 100, operated by a range-finder, along an arm 94, this arm being oriented by a differential gear 107. This gear combines the ship's heading transmitted from the head motor 30, and the target bearing transmitted from the bearing motor 110 operated by the range-under. The cursor 93 is adapted to make a special mark at intervals of time whereby the speed of the target can be measured. The angle of sight for launching torpedoes is indicated by the following means. A lamp 113 projects the shadows of a network of parallel lines on the card; the network is turned by a crank 117 till the shadows are parallel to the target course, the angle being transmitted by a current-distributor 118 and impulse motor 119 to a differential gear 121. This differential gear 121 combines this angle with the angle of the target transmitted from the differential gear 107 by a distributor and impulse motor 120, and rotates a ruler 124 marked with a suitable scale. A crank 128 with a current-distributor 130 moves a thread 125 over this scale and operates a motor 131 which is provided with a screw-shaft 132 and displaces a nut 133 provided with a slide-guide 134 whereby a crank 136 is rotated to give the correct angle of sight to the telescope 137. Provision may be made to trace the course of a second target vessel.