Abstract:
The present disclosure relates to a method and apparatus for recovering sunken wrecks. More particularly, the present invention concerns a method and apparatus for recovering sunken wrecks wherein a harpoon is launched from a submarine device, implants itself in the wreck and is provided with a rope and means for fastening a pull cable. The end of the rope which is remote from the harpoon is floated to the surface. An apparatus placed at the end of the pull cable is caused to descend along the rope, and at the end of the stroke the apparatus automatically fastens itself to the harpoon. Thereupon, the wreck is pulled up by means of the pull cable.

Description:
BACKGROUND OF THE INVENTION 
     I. Field of the Invention 
     This invention relates to a method of recovering sunken wrecks and an apparatus for the carrying out of the method. More specifically, the technical field of the invention is that of marine equipment and sighting apparatus for the refloating of sunken objects. 
     II. Description of the Prior Art 
     The customary methods of recovering wrecks at the bottom of the sea employ various means of clamping the object, such as grapnels. 
     It has also been contemplated using foam as material, as this offers the advantage of not damaging the wreck. Air-inflated plastic pockets have been produced for the refloating of sunken objects. One great disadvantage is the necessity of using frogmen for the carrying out of the operations following the locating in order to connect the wreck to the pulling device and then effect its withdrawal. 
     The stages of locating, fastening and pulling are therefore separate and not coordinated. To remove a wreck from the water requires time, labor and special equipment. 
     SUMMARY OF THE INVENTION 
     The object of the present invention is to provide a method and apparatus which simplify these operations by reducing the amount of the time, labor and equipment factors and afford numerous advantages. This object is achieved by a method which is defined by the following steps: 
     From an underwater device a harpoon is launched which embeds itself in the wreck, said harpoon being provided with means for fastening a pulling cable and with a rope rigidly connected to a float which rises to the surface. A device placed at the end of said pull cable is caused to descend along said rope and fasten itself automatically at the end of its stroke to said hooking means and said wreck then is withdrawn by means of said pull cable. 
     The apparatus for the carrying out of the method comprises a harpoon fastened to the end of a rope and an apparatus for launching said harpoon which is carried by an underwater device, said apparatus comprising a float rigidly connected with a reel on which said rope is wound, the two being fastened removably to said device. 
     The said harpoon is provided with a part for the automatic fastening of a pull cable, which part has the shape of a male tip threaded over one end of said rope and connected to said harpoon by a piece of flexible pull cable. 
     The arrangement furthermore comprises a compressed air gun for the launching of said harpoon located along the axis of said float and of said reel with which it is rigidly connected, said float being cylindrical and maintained secured to the outside of the hull of said submarine device by at least one detachable belt. 
     A control is furthermore provided within the submarine device by means of a hydraulic jack for the launching of said harpoon first and thereupon for the freeing of said float. 
     For the operation of removing the wreck, there is provided at the end of the pull cable, a device for automatic fastening to said male tip, formed of a hollow body threaded over said rope and to which the pull cable is fastened, said hollow body containing a sliding sleeve threaded over said cable which fits said male tip and has means for automatic locking onto the latter. 
     The result of the invention is a new method and apparatus for the recovering of sunken wrecks. 
     The main advantage of the invention is that it simplifies the operations and the equipment employed in the recovery of sunken wrecks and affords a saving in time and in labor. 
     The float, which is rigidly connected with the reel holding the rope which is fastened to the harpoon at one end, detaches itself from the submarine device shortly after the launching of said harpoon, permitting both the marking on the surface and the guidance up to the wreck, as a result of said rope. 
     The device for the automatic fastening of the pull cable to the hooking part with which said harpoon is provided, since it is adapted to slide along the said rope, does not require the presence of a frog man for the hooking. 
     Once the refloating has been effected, the launching apparatus and the harpoon are recovered and again fastened to the outside of the submarine device where they are ready to be used again, without requiring any special care. 
     Other features and advantages of the invention will become better understood from the reading of the following description of one embodiment, referring to the accompanying drawings. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     FIG. 1 is a longitudinal section through a portion of the apparatus in accordance with the invention. 
     FIG. 2 is an overall view of the apparatus after being fastened to the submarine device. 
     FIG. 3 is a section along line A--A of FIG. 2. 
     FIG. 4 is a section along the line F--F of FIG. 2. 
     FIGS. 5, A, B, C, and D are longitudinal sections through the automatic hooking part and fastening device, showing the main phases leading to the connecting of the harpoon to the pull cable. 
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT 
     FIG. 1 is a longitudinal section through a portion of the apparatus in accordance with the invention comprising on the one hand the harpoon A and on the other hand the launching apparatus B. 
     The harpoon A itself is comprised of the arrow tip 1 extended by three barbs the neck of which is clamped over balls (3). The body of the harpoon contains axially a headless screw (6) against which there rests one end of a spring (5) whose other end contacts a push member (4). The latter, moved forward by the pressure exerted upon the firing, pushes back an axial ball (3&#39;) moving away the other balls (3) and, therefore, the barbs. 
     The tip (1) is extended by an arrow coaxial with the gun of the launching apparatus (B). The retaining head (8) of the arrow is held locked to the launching piston the forward portion of which comprises a coaxial sleeve (9), via two balls (10), each being housed in a recess provided in the wall of the said shaft. A spring (12) holds the sleeve (9) in arrow locking position. 
     The shaft (11) is screwed into the body of the piston (14) whose rear portion bears a sealing assembly comprising alternately a scraper ring of plastic material (16) and a joint (17), this assembly contacting the inner wall of the gun (23). The sealing assembly is held on the shoulder of the body of the piston (14) by means of a metal washer (18) which is locked by a lock ring (19) which is housed in a circular groove in the body of the piston (14). 
     The body of the piston (14) is provided with a brace (13) whose front face serves as support for the locking spring (12) of the arrow and whose rear face serves as support for the shock absorbing spring (15). 
     The rear of the gun barrel (23) is surrounded by a sleeve of generally (21) shape 21 whose inside diameter narrows down at the end of said gun to constitute a shoulder against which the washer (18) of the launching piston (14) strikes. An annular ring (26) serves as joint between the portions (21) and (23). The said sleeve (21) has its wall thickened toward the outside at the front end, forming a plug for the circular cavity (48) defined by said sleeve on the one hand and a cylindrical body (20) on the other hand. The annular ring (29) assures tightness between the two parts (20) and (21). 
     The cavity (48) serves as compressed air reservoir which constitutes the source of power for the launching of the harpoon. It communicates with the gun (23) by means of three recesses (47) drilled uniformly in the wall of the sleeve (21) on the rear of the shoulder which serves as stop for the launching piston. The rear of the cavity (48) is closed by means of plug (22) which closes the portions (20) and (21) by fitting into the sleeve (21) and screwing itself in the body (20). The tightness of the chamber at the rear is assured between the plug (22) and the sleeve (21) by means of the annular ring (26), and between the body (20) and the sleeve (21) by means of the annular ring (30). 
     The charging of the cavity (48) with compressed air is assured by the channel (45) drilled in the plug (22) which is provided with a rapid filling connection (31). 
     The seal between the cavity (48) and the gun (23) is assured by means of a differential slide or piston of unequal section (24) provided with annular sealing rings (26) and (27). 
     When the cavity (48) is charged with compressed air, the difference in the pressures which act on the front and rear sections of the slide tend to move the slide (24) back towards the rear. 
     The slide is normally locked by balls (3) of a diameter greater than the thickness of the rear portion of the slide (24). 
     The holding of these balls in locking position is assured by a rod 25 which slides in the plug (22) and penetrates into the rear portion of the slide (24). Between the slide (24) and the plug (22) there is arranged a washer (28) which serves as shock absorber for the movement of the slide during firing. 
     In the tip (33) of the gun there is located a spring (35) engaged between two washers (34) which serve as shock absorbers. At the rear end of the said tip and around the gun a washer (37) assures the holding in place of a reel (38) around which there is wound up a rope (39) one end of which is connected to the harpoon. 
     A cylindrical float (36) which is separated from the reel by another washer (37) forms an extension of the said reel, first surrounding the gun, and then the body (20) whose plug (22) holds the said float in place. 
     A rope (39) is connected to the harpoon via a fastening piece (40). The latter has the shape of a longitudinally and coaxially hollowed male tip (49) so as to permit the passage, with slight play, of said rope. The male tip is extended by a cylindrical sleeve of larger outside and inside diameters, which sleeve encloses a part (42) which retains the end of said rope engaged firmly. The said part (42) flares out at its end opposite the male tip to form a rim (50) which strikes against an inner narrowing (51) of the wall of the fastening part (40) when the said rope is pulled on. 
     The fastening part (40) is connected to the harpoon A by a piece of flexible pull cable (45&#39;). 
     FIG. 2 shows an overall view of the apparatus, once fastened to the submarine device, and FIGS. 3 and 4 are sections along A--A and F--F respectively of FIG. 2. 
     A support plate (41) for the launching apparatus (B) and main cradle (43) and secondary cradle (46) are placed against the hull on the outside of the submarine by means well known to the man skilled in the art. The launching apparatus is then fastened to it by means of at least one strap (57) in the following manner: 
     The strap (57) surrounds the float (36). Each end of this strap forms a loop around a rod (54). The longitudinal axis of each rod is parallel to the axis of the launching apparatus. A ring (55) holds the strap around the said rod in fixed position. The strap is held closed by any means known to the man skilled in the art, such as a fastening plate and jacks, which is an example cited merely for purposes of illustration and not of limitation. 
     Furthermore, a jack (56) with longitudinal axis parallel to the axis of the launching apparatus is provided. The movement of the piston of the said jack controls the movement of the movable sear (53) in the direction indicated by the arrow shown in FIG. 2, as well as the movement of the rods (54) which are movable in the same direction. 
     The firing mechanism breaks down schematically as follows: 
      (1) The jack (56) is placed in operation. 
      (2) First of all, the movable sear (53) moves back, driving with it the firing finger (52) which is an extension of the rod (25). The latter, by its rearward retraction releases the balls (3). The differential piston or slide (24) is free to move rearward of the stop (19) and up to the shock absorber (28). 
     The compressed air can then exert a pressure on the rear face of the launching piston (14). Under the effect of the thrust, the arrow and the intermediate part extending it to the rear are propelled forward at very high speed and are stopped by the stop at the end of the tip of the gun 33. An impact takes place then which, due to its violence, causes the unlocking of the arrow from the sleeve in which it was locked up to that time. The harpoon which has implanted itself in the wreck which was sighted is then connected with the launching apparatus only by the rope (39). 
      (3) The freeing of the arrow having been rapidly effected it is followed by the freeing of the straps (57). This takes place, one the movable rods (54) have been sufficiently displaced in order no longer to hold them, by the recoil of the movable sear 53. The launching apparatus B has a float which then rises to the surface. 
     FIGS. 5 A, B, C, and D show in longitudinal sections the main stages leading to the fastening of the pull cable to the harpoon. 
     In FIG. 5 A there is shown an automatic fastening device (72) which is sliding over the rope (39) and is approaching the fastening part (40). 
     The fastening device (72) has a cylindrical hollow body (74) which has a recess (73) before flaring at its end closest to the fastening part (40). This body (74) is provided at its other end with at least two anchoring points (66) for the thimbles (68) intended for metal pull cables (70) connected at (69). The pull is thus exerted at several points of said body. 
     Within said body there is movably mounted a sleeve (63) which is hollowed axially over its entire length so that the rope passes through it with a small amount of play. 
     The movement of said sleeve is limited, towards the pulling cable, by a stop (76) formed of a narrowing of the inner wall of the body (74). A spring (64) rests on the one end against said stop and on the other end against the sleeve (63) having a decrease in diameter. Near the front end of said sleeve there are provided, in one and the same plane, at least two recesses in which there are housed balls (65) of a diameter greater than the thickness of the wall of said sleeve at that point. The balls can therefore protrude from the wall towards the inside or outside of said sleeve. 
     The space defined by the balls, when they restrict the inner entrance of the sleeve, prevents the passage of the male tip (49) at its shoulder (71). 
     In FIG. 5 A, before the fastening, it will be noted that the spring (64) is of maximum length L and that the balls are then located in the recess (73) and will stop the shoulder (71) when the device (72) is allowed to slide up to the part (40). The rope (39) being held taut in the direction of the arrow shown in FIG. 5 B, the device (72) hooked to the end of the pull cable continues to slide under the effect of its weight. The conical bearing surface (77) of the part (40) rests against the balls (65) and pushes back the sleeve (53) the movement of which compresses the spring (64) the length of which decreases and becomes 1. The balls (65) then arrive into the cavity (75) and can move freely towards the outside of the sleeve (FIG. 5 B). This takes place under the thrust which the conical bearing surface (77) of the tip (49) exerts. 
     The retraction of the balls permits the tip (49) to penetrate completely into the sleeve (63) and the device (72) to continue to descend under the effect of its weight until the conical shoulder (78) of the part (40) comes against the flare (79) of the body (74). 
     At the same time, as soon as the shoulder (71) has arrived in the cavity (75) and has passed in front of the balls (65), the spring (64) which tends to resume its normal length L, lengthens in the direction of the arrows pushing the sleeve (63) and, from there, the balls. 
     The latter, in order to follow the narrowing of the wall of the body (74) are forced to move towards the inside of the sleeve. This movement, indicated by the arrows in FIG. 5 C, explains the automatic locking of the fastening part (40). 
     This locking is illustrated in FIG. 5 D after the movement of the sleeve (63) is effected in the direction of the arrow. The spring has again found its original length L. The recess (73) prevents the movement of the balls towards the outside of the sleeve. 
     When a lifting force is exercised on the pull cable, the rising of the assembly (72) applies the shoulder (71) against the balls which assure an effective locking. The pulling force exerted on the body (74) of the assembly (72) is transmitted to the sleeve (63) via two nuts (67) screwed on to the threaded end of said sleeve, and then to the part (40) via the balls (65) and then to the harpoon which is implanted in the wreck by means of the flexible pull cable. 
     Of course various modifications can be made by the man skilled in the art in the process and apparatus described, without going beyond the scope of the invention, the said process and apparatus having been described solely by way of illustration and not of limitation.