US3898609A

US3898609A - Underwater exploration device

Info

Publication number: US3898609A
Application number: US417939A
Authority: US
Inventors: Christian Charles
Original assignee: CENTRE NAT EXPLOIT OCEANS
Current assignee: CENTRE NAT EXPLOIT OCEANS; CENTRE NATIONAL POUR L'EXPLOITATION DES OCEANS (CNEXO)
Priority date: 1972-11-21
Filing date: 1973-11-21
Publication date: 1975-08-05
Anticipated expiration: 1992-08-05
Also published as: BE807273A; ZA738751B; FR2207318A1; NL7315958A; DE2358064C2; AU6261473A; NL164406C; GB1391750A; JPS5433440B2; NO136770B; CA991431A; NL164406B; FR2207318B1; NO136770C; ES420739A1; SE409769B; IT1001031B; JPS4982099A; DE2358064A1

Abstract

There is disclosed a smoke generator for use on underwater exploration devices. Upon descent of the exploration device, the smoke generator is automatically armed when hydrostatic pressure increases to a predetermined level. Upon ascent, the smoke generator is automatically triggered when hydrostatic pressure decreases to a predetermined level.

Description

Unite States 11 1 1111 3,898,609

Charles Aug. 5, 1975 [5 UNDERWATER EXPLORATION DEVICE 3,066,324 12/1962 Snyder 81'. al. 9/8 R 3,196,789 7/1965 Fasig etal 102 7 [75] Inventor? Charles Brest France 3,762,327 10/1973 Murray et al. 102 90 X [73] Assignees: Centre National pour lExploitation des Oceans (CNEXO); Le Nickel,

both of Paris, France; P interest Primary Examiner-Richard A. Farley to each Attorney, Agent, or Firm-Fleit & Jacobson [22] Filed: Nov. 21, 1973 21 Appl. No.: 417,939

[57] ABSTRACT [30] Foreign Application Priority Data Nov. 21, 1972 France 72.41224 There IS disclosed a smoke generator for use on un- 52 us. (:1 340/4 R; 9/8 R; 102/90 derwater exploration devices descent of the 51 Int. Cl. G08b 5/40 Plomtio device the Smoke generator is automatically [58] Field of Search 340/4 102/9O 7 armed when hydrostatic pressure increases to a predetermined level. Upon ascent, the smoke generator is automatically triggered when hydrostatic pressure de- [56] References Cited creases to a predetermined level.

UNITED STATES PATENTS 3,048,] 11 8/1962 Baker et al. 102/54 X 11 Claims, 3 Drawing Figures PATENTED 5|975 3,898,609

FiGj

1b H63 3a 3.2 36 34 35 a1 UNDERWATER EXPLORATION DEVICE This invention relates to underwater exploration devices.

lt is known that, in exploring sea-beds, the devices used are, for example, photographic devices or sampling devices, and are frequently of the type referred to as free-fall which means that they are released from a ship to which they are not linked. Being secured to ballast and to floats, the free-fall devices sink in the water under the action of the ballast, and then contact the sea-bed whereupon the ballast is released and the taking of photographic pictures or the collection of samples is initiated by means of a variety of automatic devices which will not be described herein since they do not form part of the present invention. Then, under the action of the floats, the devices rise to the surface to be retrieved.

The ship entrusted with the retrieval of the devices, which is usually the launching ship, is commonly far from the exploring devices at the instant when they surface, and it is necessary that the devices should be equipped with marking means which allows their detection from a distance. These marking means are of several kinds, including radio beacons, flashing light generators, inflatable balloons, and smoke generators. The present invention specifically relates to marking means of the last-mentioned kind.

One of the objects of the invention is to produce a submersible smoke generator which will give off smoke automatically when it reaches the surface of the water after having descended to and returned from the seabed.

Another object of the present invention is to provide an apparatus of this kind which is watertight up to depths of as much as 6,000 metres.

A further object is to provide an apparatus of this kind which offers great operational reliability and in particular is protected against accidental actuation, for example upon being dropped overboard.

A complementary object of the invention is to provide a smoke generator in which smoke discharge does not occur until the apparatus has actually reached the surface of the water.

Another object of the invention is to provide an apparatus of this kind which may easily be assembled and dismantled, and which lends itself to numerous consecutive operations.

In accordance with the invention there is provided an underwater apparatus of the smoke generator kind, comprising a generally cylindrical body; a firing control device arranged in the cylindrical body to adopt an idle position and an actuating position; means for influencing the firing control device when an external hydrostatic pressure is exerted on the underwater apparatus and for causing the firing control device to shift from the idle position to the actuating position when the external hydrostatic pressure is reduced virtually to zero; means for igniting a smoke-producing compound in the cylindrical body when the firing control device is shifted to the actuating position; smoke discharge means; and means for plugging the discharge means while the smoke-producing compound remains unignited and for opening the discharge means when the compound is ignited.

The firing control device preferably comprises a metal priming cylinder which slides within an insulating sleeve in said cylindrical body and which is displaceable between a standby position in engagement with an abutment formed within the sleeve and an actuating position in engagement with a metal disc which is mounted within but electrically insulated from the cylindrical body; an elastic element arranged to urge the priming cylinder towards the idle position; a firing cartridge connected electrically at one end to the cylindrical body and arranged to be connected at the other end to one terminal of an electric cell; and means for connecting the other terminal of the electric cell to the priming cylinder.

The elastic element specified in the preceding paragraph advantageously comprises a metal tension spring firmly joined at one end to the priming cylinder, and at the other end to a second metal disc which abuts against a shoulder formed in the insulating sleeve.

In this case, the means for connecting the other terminal of the electric cell or battery electrically to the priming cylinder comprise the metal tension spring paired with a connecting wire, and a metal compression spring arranged between the second metal disc or washer and the other terminal of the electric cell. This compression spring also serves the purpose of urging the cell against the firing cartridge and of holding the second metal disc against its shoulder.

The said means for influencing the firing control device preferably comprise a sleeve screwed to the end part of the cylindrical body and having an axial bore with an external conical recess; a control pin slidingly mounted in the axial bore of the sleeve and terminating in a conical part projecting towards the inside of the cylindrical body; two resilient blades joined together along the greater proportion of their length and which are firmly joined at their one ends to the firing control device and spread apart in Vee-shape at their other ends close to which they are formed with openings in which the projecting ends of the conical part are held; and an elastic cover which caps the sleeve and the corresponding end of the cylindrical body and which, when under the action of external pressure, is arranged to assume the shape of the conical recess of the said sleeve and to urge the control pin inwards, said control pin being firmly joined to the said elastic cover, for example by overmoulding.

It will be understood that, when the smoke generator apparatus in accordance with the invention sinks towards the sea-bed, the hydrostatic pressure exerted on the elastic cover holds the cover against the conical recess of the sleeve screwed to the extremity of the cylindrical body and, at the same time, urges the control pin towards the inside of the assembly. The projecting cone of this pin is then engaged between the resilient blades without the remainder of the firing control device shifting from the idle position.

While the apparatus is rising towards the surface of the water after release of the ballast, as mentioned above, no smoke is generated because, under the action of the external pressure, the elastic cover continues to hold the control finger in position. However, when the apparatus reaches the surface or just before it reaches the surface, the hydrostatic pressure drops virtually to zero, and the elastic cover regains its initial form and withdraws the control pin which pulls on the blades in which it is caught whilst drawing the firing control device towards its actuating position. The smoke-producing compound is then ignited, as will subsequently be described, and discharge of smoke begins.

It is thus clear that the smoke is discharged automatically when the apparatus returns to the surface, without the need of an external control device.

Suitably, the elastic cover mentioned above is formed in its plane external surface with a retaining groove wherein is inset a rigid protective plate formed with at least one hole. Any accidental actuation upon being dropped into the water is thus rendered virtually impossible: if a pressure is exerted inadvertently on the actuating end part of the apparatus in accordance with the invention, the rigid protective plate prevents transmission of this pressure to the control elements.

In one form, the smoke discharge device comprises a metal cover capping the corresponding end of the cylindrical body; an elastic cover capping the said metal cover and a part of the cylindrical body; and an apertured cup-like member which is arranged with its base facing inwardly of the cylindrical body, and with the interpositioning of a toroidal sealing joint, between the charge of said smoke-producing compound and the said metal cover.

Thus, the smoke produced by the smoke-producing compound escapes through the orifice of the cup-like member after having pushed back the metal cover and the elastic cover which cap that end of the apparatus.

The means of igniting the smoke-producing compound when the firing control device shifts to the actuating position preferably comprise a pyrotechnic delay device such as a slow fuse installed in an axial tube extending from the firing cartridge towards the smokeproducing compound; a pyrotechnic connecting element and an intermediate combustible compound between the fuse and the smoke-producing compound; means of connecting the space situated between the slow fuse and the axial tube to a toroidal groove located within the cylindrical body; a sealing member outwardly sealing off the toroidal groove; and an elastic sleeve surrounding the cylindrical body at either side of that sealing member.

This arrangement enables gases released by the combustion of the slow fuse to escape outwards, which is important for uniformity of combustion. The function of the slow fuse is to create a delay between the instant at which the firing action is triggered and that at which the discharge of smoke begins. In fact, the firing action occurs a little before the apparatus has risen to the surface, and it is appropriate to prevent the ignition of the smoke-producing compound under water, in order to eliminate the risk of quenching. Finally, the intermediate compound serves the purpose of assisting the ignition of the smoke-producing compound.

The cylindrical body is advantageously constructed in two parts which are inserted into a cylindrical coupling member with the interpositioning of a sealing joint or packing, these two parts being held in position by means of a nut screwed between them. It will be appreciated that this arrangement eases the assembly and dismantling of the apparatus in accordance with the invention, which may be used again after replacement of, for example, the pyrotechnic compounds.

An embodiment of the present invention will now be described, by way of example, with reference to the accompanying drawings in which:

FIG. 1 shows one end part of smoke-generator apparatus according to the invention, in longitudinal section;

FIG. 2 shows the central portion of the apparatus, also in longitudinal section; and

FIG. 3 shows the other end part of the apparatus, again in longitudinal section.

The submersible smoke-generator apparatus in accordance with the invention is illustrated in three parts in the drawings. In each Figure of the drawings, the elements have been denoted by the same reference numerals.

Referring to the drawings, the smoke-generator apparatus comprises a cylindrical body formed in two parts 1a and lb and made of a metal resistant to corrosion by water, such as an aluminium alloy containing magnesium. Actuating elements are denoted generally by reference 2 in FIG. 1, reference 3 denotes an electric cell or battery (FIG. 1), and a charge of smokeproducing powder 4 is shown in FIGS. 2 and 3. Elements for discharging the smoke produced by the powder charge 4, after firing, are denoted generally by reference 5 in FIG. 3. To simplify the description, the terms actuating end will be applied to that part which is illustrated in FIG. 1, and the term smoke discharge end will be applied to that part which is illustrated in FIG. 3. The terms inside" and outside are used to refer to the inside and outside of the apparatus as a whole.

The actuating elements 2 comprise a guide sleeve 6 which has an outer conical recess and which is screwed into the end of body part 1a. The sleeve 6 has an axial bore within which a pin 7 is slidingly mounted. Towards the outside, the pin 7 has its head secured to an elastic cover 8, preferably of vulcanised rubber such as NEO- PRENE, which caps the guide sleeve 6 and the extremity of the cylindrical body la. On its outer surface, the cover 8 is provided with a protective metal disc 9 having a central hole and held within a groove formed in the cover 8.

Towards the inside, the pin 7 terminates in a projecting conical part 10 the apex of which is located within a V-formed at the extremity of two coupled blades 11. An opening 12 is formed in each of these blades, close to where they are bent outwardly to form a V and the size of these openings is such that, when the conical part 10 of the pin 7 is forced between the blades 11, thus spreading the blades apart, the base of the cone is caught in the openings 12.

Inside the cylindrical body part 1a, a metal contact disc or washer 13 is gripped between the end of the guide sleeve 6 and an insulating sleeve 14 as will hereinafter be described. The blades 11 are mounted on a metal priming cylinder 15 which can slide within the insulating sleeve 14, between the contact disc or washer 13 and a first shoulder or abutment formed within the sleeve. This cylinder 15 is urged away from the contact disc 13 by a tension spring 16 which is anchored on a metal disc 17 held against a second shoulder formed in the sleeve 14. Towards the smoke discharge end, the sleeve 14 also contains the electric cell or battery 3 whose positive terminal is pressed into engagement with a contact screw 18 by a spring 19 interposed between the base of the cell, that is its negative terminal, and the metal disc 17.

Moving towards the smoke discharge end of the apparatus, a cartridge 20 is provided with a filament 21 which is connected at one end to the contact screw 18 and at the other end to the metal casing of the cartridge 20. The insulating sleeve 14 bears against a second shoulder formed within the body part 1a, with the interpositioning of a toroidal joint packing-14a. The disc 17 is held in position by the tension spring 16 and by the compression spring 19, the latter spring also acting to hold the cell 3 fast in its housing. The method of securing the cartridge 20 and its contact screw 18 will subsequently be described.

The operation of this actuating system is as follows. When the smoke'generator apparatus sinks below the surface of the water, the hydrostatic pressure pushes the elastic cover 8, protected by the metal disc 9 against any accidental action, into the conical recess of the sleeve 6, and this moves the conical part 10 of the pin 7 between the blades 11 where it is caught, as has been stated above.

When the apparatus rises to the surface again, the reduction of the pressure on the elastic cover 8 causes the pin 7 to slide outwards as to draw the blades 11 and the priming cylinder 15. The priming cylinder thereupon comes into contact with the metal disc 13, so that the electrical circuit incorporating the cell 3 is closed. Starting from the negative terminal, this circuit comprises the spring 19, the spring 16 paired with a connecting wire which is not illustrated, the cylinder 15, the disc 13, the cylindrical body part 1a, the filament 21, and the contact screw 18.

The flow of current through the filament 21 heats the filament to the point of incandescence which ignites the cartridge 20 which, in turn, ignites the smokeproducing powder.

Referring now to the smoke-generating part, the elements are illustrated in FIGS. 2 and 3 and comprise the cylindrical body part lb mounted on the body part la by means of a nut 22 and a coupling element 23. More particularly, the body 1a receives the coupling element 23 with the interpositioning of a toroidal joint or packing 24 and a sealing washer, and the nut 22 between the body parts la and lb holds the whole in position; the nut 22 has a shoulder which bears on the end of the body part la. The connection between these parts is shielded by a sleeve 25 of a synthetic material such as Neoprene.

The cartridge 20 is screwed into the coupling element 23 at the actuating end side of the latter.

The coupling element 23, which has an axial through opening, is also pro vided with vent holes 26 connecting its axial opening to a groove 27 formed at the end and in the inner surface of the nut 22. A metal washer 28 closes this groove 27 and bears at its other side against a shoulder or abutment formed in the sleeve 25.

A slow fuse 29 connects the cartridge 20 to the smoke discharge end part of the apparatus, passing through an axial tube 30 which penetrates into the bore of the coupling element 23 and which is firmly joined to that element. The smoke-producing charge 4 is situated between the tube 30 and the body part 1b.

The smoke discharge elements 5, illustrated in FIG. 3, comprise a metal cover 31 which caps the extremity of cylindrical part 1b. The cover 31 itself is capped by a cover 33 which is made of a synthetic material such as NEOPRENE and which also covers a part of the body part lb. A washer 34, in the form of an axially apertured cup, is arranged with the base facing the body part 1b between the smoke-producing charge and the cover 31, with interpositioning of a toroidal joint 35.

Referring to FIG. 3, which shows the extremity of the slow fuse 29 and the tube 30, an intermediate combustible mixture 36 fills the extremity of the body part lb. A connecting pyrotechnic element 32 ensures the propagation of burning between the slow fuse 29 and the intermediate mixture 36.

The operation of the smoke discharge system is as follows. Ignition of the cartridge 20 which occurs as has been stated above, effects the ignition of the slow fuse 29 passing into the tube 30. The gases released by the combustion of this fuse may escape outwardly through the passages 26 by pushing back the washer 28 and the elastic sleeve 25.

The slow fuse ignites the connecting pyrotechnic element 32 which, for its part, ignites the intermediate compound 36 and, in this case too, the combustion gases may escape as has been stated, by passing through the space present between the tube 30 and the slow fuse 29.

The intermediate compound 36, for its part, ignites the smoke-producing charge 4, and the smoke thus produced and passing through the orifice of the washer 34, causes the

covers

31 and 33 to be blown off. The smoke then discharges from the apparatus. This smoke discharge renders it possible to locate the position of the smoke generator apparatus from afar, and thus easily retrieve the associated underwater exploration device.

What we claim is:

I. An underwater apparatus of the smoke generator kind, comprising a generally cylindrical body; a resilient cap sealing one end of said body, firing control means arranged in the cylindrical body connected with said resilient cap to be acted upon by hydrostatic pressure transmitted through said cap, said firing control means being arranged to adopt a repose position, an idle position, and an actuating position; actuating means for influencing the firing control means responsive to a predetermined external hydrostatic pressure exerted on the resilient cap to cause the firing control means to shift from the repose position to the idle position, and to shift from the idle position to the actuating position responsive to the external hydrostatic pressure being reduced virtually to zero; ignition means for igniting a smoke-producing compound in the cylindrical body responsive to the firing control device being shifted to the actuating position; smoke discharge means; pressure detachable means for plugging the discharge means while the smoke-producing compound remains unignited and for detaching from and opening the discharge means responsive to pressure being generated when the smoke producing compound is ignited, and protective means protecting said firing control means from accidental actuation.

2. An apparatus according to claim 1, in which said firing control device comprises a metal priming cylinder which slides within an insulating sleeve in said cylindrical body and which is displaceable between a standby position in engagement with an abutment formed within the sleeve and an actuating position in engagement with a metal disc which is mounted within but electrically insulated from the cylindrical body; an elastic element arranged to urge the priming cylinder towards the idle position; a firing cartridge connected electrically at one end to the cylindrical body and arranged to be connected at the other end to one terminal of an electric cell; and means for connecting the other terminal of the electric cell to the priming cylinder.

3. An apparatus according to claim 2, in which said elastic element comprises a metal tension spring anchored at one end on said priming cylinder and at the other end connected to a second metal disc which abuts against a shoulder formed in said insulating sleeve, said means for electrically connecting the other terminal of the electric cell to said priming cylinder comprising said metal tension spring and a metal compression spring located between said second metal disc and the other terminal of the electric cell and also arranged to urge the electric cell against said firing cartridge and to hold said second metal disc against its shoulder.

4. An apparatus according to claim 3, in which said insulating sleeve is located in said cylindrical body, at one extremity by said metal disc which is screwed into the cylindrical body, and, at the other end, by means of a toroidal joint urged against a shoulder formed in the cylindrical body.

5. An apparatus according to claim 1 in which said means for influencing the firing control device comprise a guide sleeve which is screwed into said cylindrical body and is formed with an axial bore having a conical recess at its outer end; a control pin slidably arranged in the axial bore of the guide sleeve and terminating inwardly of the cylindrical body in a projecting conical part; two elastic blades joined together along the greater proportion of their lengths, firmly joined at their ends to the firing control device, and spread apart in V shape at their other ends, close to which the blades are formed with orifices arranged to engage with the projecting conical part of said control pin; and an elastic cover capping the guide sleeve and the corresponding end of the cylindrical body and arranged to assume, under the action of external hydrostatic pressure, the shape of the conical recess of the guide sleeve and to urge inwardly said control pin to which it is secured.

6. An apparatus according to claim 5, in which said elastic cover is formed in its plane external surface with a retaining groove which receives a rigid protective disc formed with at least one hole.

7. An apparatus according to claim 6, in which said elastic blades are firmly secured to said priming cylinder.

8. An apparatus according to claim 7, in which the end of said guide sleeve screwed into the cylindrical body firmly engages said metal disc to ensure electrical contact with the cylindrical body.

9. An apparatus according to claim 1 in which said smoke discharge means comprise a metal cover capping the corresponding extremity of said cylindrical body, and an elastic cover capping said metal cover and a part of the cylindrical body.

10. Apparatus according to claim 1 in which said means for igniting the smoke-producing compound when the firing control device is shifted to the actuating position comprise a delayed pyrotechnic firing device and a device which is arranged to allow the discharge of the gases generated by the pyrotechnic delay device and which comprises a toroidal groove formed inside said cylindrical body and in communication with the said pyrotechnic delay device, a sealing washer outwardly sealing said toroidal groove, and an elastic sleeve surrounding the cylindrical body at either side of the sealing Washer,

11. An apparatus according to claim 2 in which said cylindrical body is formed in two parts which are inserted into a cylindrical coupling member with the interpositioning of a sealing joint, said two parts being held in position by means of a nut screwed between

Claims

1. An underwater apparatus of the smoke generator kind, comprising a generally cylindrical body; a resilient cap sealing one end of said body, firing control means arranged in the cylindrical body connected with said resilient cap to be acted upon by hydrostatic pressure transmitted through said cap, said firing control means being arranged to adopt a repose position, an idle position, and an actuating position; actuating means for influencing the firing control means responsive to a predetermined extErnal hydrostatic pressure exerted on the resilient cap to cause the firing control means to shift from the repose position to the idle position, and to shift from the idle position to the actuating position responsive to the external hydrostatic pressure being reduced virtually to zero; ignition means for igniting a smoke-producing compound in the cylindrical body responsive to the firing control device being shifted to the actuating position; smoke discharge means; pressure detachable means for plugging the discharge means while the smoke-producing compound remains unignited and for detaching from and opening the discharge means responsive to pressure being generated when the smoke producing compound is ignited, and protective means protecting said firing control means from accidental actuation.

10. Apparatus according to claim 1 in which said means for igniting the smoke-producing compound when the firing control device is shifted to the actuating position comprise a delayed pyrotechnic firing device and a device which is arranged to allow the discharge of the gases generated by the pyrotechnic delay device and which comprises a toroidal groove formed inside said cylindrical body and in communication with the said pyrotechnic delay device, a sealing washer outwardly sealing said toroidal groove, and an elastic sleeve surrounding the cylindrical body at either side of the sealing washer.

11. An apparatus according to claim 2 in which said cylindrical body is formed in two parts which are inserted into a cylindrical coupling member with the interpositioning of a sealing joint, said two parts being held in position by means of a nut screwed between them.