Patent GB-190728284-A (GB)
Title: Improved System of Submarine Automatic Mine.
Inventor: ELIA GIOVANNI EMANUELE
Filed: 1907-12-23
Granted: 1908-12-10
Abstract: 28,284. Elia, G. E. Feb. 18, [date applied for under Patents Act, 1901.] Explosive mines.-Submarine mines are arranged so that, at the time of explosion, there is no vacant space in proximity to the explosive charge, which would reduce the effective power of the explosion. The mine is adapted to float at a given depth. Means for laying and raising are also described. The mine comprises mainly a casing 5 for the explosive charge, a float 1, and an anchor 11. The casing 5 carries a detonator tube 20, and is closed by a plate 14, which has a socket 19 to accommodate the end of the tube 20, and an attachment 18 for the anchoring-cable. The plate 14 is attached by screws to a support 15. The float 1 carries a frame 32, within which are three drums 24, 25, 29 with ropes 27, 28, 30, a ball 21 attached by a cord 26 to a lever catch 23, a socket 22 at the end of this lever, and a retaining cupola 51. The ropes 27, 28 pass over pulleys 42, 42<1>, and are then joined together. The rope 30 is about 60 cm. shorter than either of the others, and is attached to a rod 34 secured by a pin 36 to a spring-controlled hammer 31. The cupola 51 is mounted on a spindle 55 operated by a compound drum 60 and a worm gear 53. One part of the drum 60 is connected by a rope 56 to a buoyant cap 48, and the other part by a rope 61 to a weight 7. The spindle 55 is normally locked by a soluble seal 52 and the cap 48 by seals 49. The gearing 53 is protected by a tight box filled with oil. The anchor 11 forms an extension to the float 1, and is normally secured thereto by catches 10, 76, adapted to be released by means of rods 75 by a slight motion of a heavy ring 74 when keys 80 are unfastened. The anchor contains a drum 64 for the cable 33, which passes through a guide 81 mounted in a slot 82 parallel to the axis of the drum 64, to ensure that the cable is regularly rolled on the drum. A dash-pot 66 is disposed on an eccentric to damp the rotation of the drum. The drum has a ratchet-wheel 69 normally locked by a lever 68 controlled by an adjustable spring 70. A plummet 71 normally retained by keys, carries a coiled rope 72, by means of which it is attached to a rod 73 connected to the lever 68. A hook 83 provides an attachment for a location float. Several such mines may have a common location float. The mine, when thrown overboard acts as follows. The plummet 71 falls out to the length of its rope 72, the pull on which disengages the lever 68 from the rack 69, and the ring 74 releases the catches 10, 76. The anchor falls until the plummet reaches the bottom of the sea, whereupon the lever 68 again locks the drum 64. The anchor next fills with water and draws down the float until the anchor reaches the bottom of the sea. Thus, the length of the plummet line determines the depth of immersion of the float 1. When the seals 49, 52 have dissolved, the cap 48 rises and drives the cupola 51 round under the socket 22, winding up the weight 7. If a boat then comes in contact with the mine, the ball 21 upsets and pulls off the lever catch 23, and releases the drums 24, 25, 29, the explosive casing 5 runs out, and the shorter rope 30, when fully unwound, pulls the rod 34 and compresses the spring 35 until the pin 36 is sheared and the hammer 31 flies back and fires the mine. Thus, when the explosion occurs, the float is sufficiently far from the casing of the explosive. When an unexploded mine is raised, the weight 7 draws the cap 48 and the cupola 51 back to their original position. A metallic safety is then applied to replace the broken seal 52. The weight 7 is heavy enough to prevent a current of 7 knots an hour from driving off the cap 48. An arrangement for laying such mines at a moderate speed comprises a floor p, a rocking platform p', and a slide f, as shown in Fig. 11. A raising-apparatus of the same nature comprises a rollerr with a central groove k, side guides g, rope guards s, an inclined plane p<11>, and a windlass m, as shown in Figs. 15 and 16.