| US4073079A | 1978-02-14 | |||
| EP0134312A1 | 1985-03-20 | |||
| US4019380A | 1977-04-26 | |||
| US3580511A | 1971-05-25 | |||
| DE2942302A1 | 1981-04-30 |
| 1. | [received by the International Bureau on 6 August 1987 (06.08.87); original claims 1 and 2 amended; claims 39 unchanged (1 page)] A remote underwater excavator comprising a tube wherein is mounted a propeller or multiple venturi pipes that when energised underwater produce a flow of water having no significant hydrostatic head with sufficient volume and velocity to carry away seabed materials on the current thus produced . A remote underwater excavator as claimed in claim 1 above wherein an annulus shaped intake external to and parallel to the flow of water produces suction to counteract the thrust produced by the flow of water. |
| 2. | A remote under water excavator as claimed in claim 1 or claim 2 wherein vanes are set in the water outlet to counteract torque developed by the propeller. |
| 3. | A remote underwater excavator as claimed in claim 1 or claim 2 or claim 3 wherein a buoyancy tank maintains the machine in an upright posture even when the machine is not energised . |
| 4. | A remote underwater excavator as claimed in claim 1 or claim 2 or claim 3 or claim 4 wherein a rigid or flexible foot anchors the machine in position on the bottom by friction and weight. |
| 5. | A remote underwater excavator as claimed in claim 1 or claim 2 or claim 3 or claim 4 or claim 5 wherein the buoyancy and anchor means will maintain the machine at a constant altitude above the underwater bottom (i.e. it will descend as the bottom is excavated beneath it). STATEMENTUNDERARTICLE 19 The amendment to claim 1 emphasises the underlying principle embodied by the subject invention in its capability of generating and applying a large low velocity column of water having no significant hydrostatic head. This enables the invention to excavate large volumes of subsea material which are then carried away by the current generated by the flow which the machine produces. The lack of significant hydrostatic head enables a low energy method with the additional benefit of permitting sensitive items within the material being excavated to be cleared in a non destructive manner. This low energy approach is contrary to conventional technology which has saught to exploit high pressure in displacing sub sea materials (e.g. US A. 4073079 Klinefelter) by concentrating on injecting a small diameter high velocity column of water with concommitant high hydrostatic head. Such conventional methods are restricted by escallating power requirements from attempting large volume ' excavation operations, as well as having an inherantly distructive tendancy with respect to sensitive items buried within the excavated material, and requiring a separate current or tidal flow to transport displaced material away. The subject invention is also different in concept from another conventional technology which relies on sucking subsea material the efficacy of which is constrained by being limited to the the immediate radius of suction and being reliant upon substantial escallat on of power requirements as depth and size of radius increase. In summary the invention is based on the premise that displacement and removal of subsea materials depends not on pressure (high energy) but on flow (low energy) which washes away the sub sea material layer by layer. The amendement to claim 2 draws attention to the fact that the invention produces a suction force to oppose thrust, which apart from differing in concept from the less energy efficient conventional use of retro jets (e.g. US A. 4073079 Klinefelter) is different in concept from the contra rotating device (EP, A, 0134312 Dosbouw). CLAIMS 1 A remote underwater excavator comprising a steel tube wherein is mounted a propeller or multiple venturi pipes that when energised underwater produce a flow of water of sufficient volume and velocity to blow away seabed materials . |
| 6. | 2 A remote underwater excavator as claimed in claim 1 above wherein an annulus shaped intake external to and parallel to the flow of water counteracts the thrust produced by the flow of water. |
| 7. | 3 A remote under water excavator as claimed in claim 1 or claim 2 wherein vanes are set in the water outlet to counteract torque developed by the propeller 4 A remote underwater excavator as claimed in claim 1 or claim 2 or claim 3 wherein a buoyancy tank maintains the machine in an upright posture even when the machine is not energised . |
| 8. | 5 A remote underwater excavator as claimed in claim 1 or claim 2 or claim 3 or claim 4 wherein a rigid or flexible foot anchors the machine in position on the bottom by friction and weight. |
| 9. | 6 A remote underwater excavator as claimed in claim 1 or claim 2 or claim 3 or claim 4 or claim 5 wherein the buoyancy and anchor means will maintain the machine at a constant altitude above the underwater bottom (i.e. it will descend as the bottom is excavated beneath it). SUBSTITUTE SHEET . |
| 10. | A remote underwater excavator as claimed in claim 1 or claim 2 or claim 3 or claim 4 or claim 5 or claim 6 wherein nets or sieves fitted to the anchor means can collect samples washed out of the bottom by the flow of water . |
| 11. | A remote underwater excavator as claimed in claim 1 or claim 2 or claim 3 or claim 4 or claim 5 or claim 6 or claim 7 wherein by altering the buoyancy of the buoyancy tank means the machine can be made negatively, neutrally or positively buoyant. |
| 12. | A remote underwater excavator substantially as described herein with referance to figure 1 of the accompanying drawing. SUBSTITUTE SHEET. |
INTERNATIONAL APPLICATION PUBLISHED UNDER THE PATENT COOPERATION TREATY (PCT)
(51) International Patent Classification - : (11) International Publication Number: WO 87/ 047
E02D 1/04 Al (43) International Publication Date: 13 August 1987 (13.08.
(21) International Application Number: PCT/GB87/00099 (81) Designated States: AT (European patent), AU, BE ( ropean patent), CH (European patent), DE (Eu
(22) International Filing Date: 10 February 1987 (10.02.87) pean patent), DK, FR (European patent), GB (Eu pean patent), IT (European patent), JP, LK, LU ( ropean patent), MG, NL (European patent), NO,
(31) Priority Application Number : 8603189 (European patent), US.
(32) Priority Date: 10 February 1986 (10.02.86)
Published
(33) Priority Country: GB With international search report. Before the expiration of the time limit for amending claims and to be republished in the event of the rec
(71) Applicant (for all designated States except US): CON¬ of amendments.
SORTIUM RECOVERY LTD. [GB/GB]; 134 Lots Road, London SW10 0RJ (GB).
(72) Inventor; and
(75) Inventor/Applicant (for US only) : SILLS, Nicholas, Vic¬ tor [GB/GB]; 41 St. Georges " Road, Petts Wood, Kent (GB).
(74) Agent: SINCLAIR-BROWN, N. ; 12 Witley Court, Co- ram Street, London WC1 (GB).
(54) Title: REMOTE UNDERWATER EXCAVATOR AND SAMPLER
(57) Abstract
An underwater excavator in which when energised by a supply of hydraulic oil or other means a propeller (3) is set in motion with water being drawn in through the cylindrical tube (5) and expelled at the water outlet (6) thereby creating a flow of water of sufficient volume and velocity to blow away seabed materials. The design of the machine is such that thrust and torque are counteracted by the suction force de¬ veloped at the water intake (4). Optional filter nets or sieves may be fixed to the foot of the ma¬ chine to capture samples of the material washed out of the seabed.
FOR THE PURPOSES OF INFORMATION ONLY
Codes used to identify States party to the PCT on the frontpages of pamphlets publishing international appli¬ cations under the PCT.
AT Austria FR France ML Mali
AU Australia GA Gabon MR Mauritania
BB Barbados GB United Kingdom MW Malawi
BE Belgium HU Hungary NL Netherlands
BG Bulgaria rr Italy NO Norway
BJ Benin JP Japan RO Romania
BR Brazil KP Democratic People's Republic SD Sudan
CT Central African Republic ofKorea SE Sweden
CG Congo KR Republic of Korea SN Senegal
CH Switzerland LI Liechtenstein SU Soviet Union
CM Cameroon LK Sri Lanka TD Chad
DE Germany, Federal Republic of LU Luxembourg TG Togo
DK Denmark MC Monaco US United States of America
FI Finland MG Madagascar
REMOTE UNDERWATER EXCAVATOR AND SAMPLER
This invention relates to a method of excavating and sampling materials under any depth of water utilising a machine capable of generating and directing a jet of water.
Present methods of underwater excavation using a water jet rely on diverting the water jet from a ship's propeller, vertically downwards and washing a crater in the river, lake or seabed. This system cannot be used to sample the washed out materials nor outside shallow water or where access for the ship is not possible. The present invention concerns an excavation machine that can be deployed remotely from a ship or other vehicle in any depth of water and having an additional capability of sampling washed out materials.
According to the present invention there is provided a cylindrical tube through which a jet of water is generated by means of either a propeller or multiple venturi pipes. A water intake is fitted to the top of the tube in such a configuration as to enable the the suction from the the intake to oppose the thrust from the outlet thereby stabilising the machine whilst in operation. When in propeller mode vertical vanes in the water outlet act to prevent the swirling motion of the water jet normally produced by a propeller so that a laminar flow of water is produced, and small deflectors are fitted at the bottom of the vanes to oppose the torque developed by the propeller and thus prevent the machine rotating. An anchor leg extending fzoτ_ the base of the machine is used to keep the machine at a fixed distance from the surface on which it is operating. Fins attached to the base of the anchor leg by sinking into the ground assists in
maintaining the machine in position and when in propeller mode also prevents the machine rotating. Filter baskets attached to these fins can sample materials washed out during excavation. A buoyancy tank on top of the machine maintains the machine in an upright position. A lifting eye can be incorporated for ease of deployment and the machine can be constructed in such a way as can be easily dismantlable .
A specific embodiment of the invention will now be described by way of example with reference to the accompanying drawing Figure 1 .
Referring to Figure 1 when power is received by the motor 1 from a power source via an umbilical connection 2 the propellor 3 is set in motion, water is drawn in through the water intake 4 then through the cylindrical tube 5 and expelled as a water jet at the water outlet 6. The suction force developed at the water intake helps to oppose the thrust developed at the water outlet by the water jet and keep the machine in contact with the seabed 7. The speed of the propeller and thereby the velocity of the water jet can be controlled from the surface using a valve set in the umbilical. It is thereby possible at an illustrative velocity of say 5 metres per second for the water jet to be sufficiently powerful to mobilise and displace solid materials such as sand, gravel, pebbles and rocks from underneath the invention to a radius of at least 2 metres. As excavation continues a crater 8 is formed and continues to deepen until a steady state is achieved whereby excavation of the crater is equalized by infill of the crater's sides. Heavy objects such as large rocks or dense materials such as metals will generally remain in the crater and can be collected separately for example by divers. The machine is maintained in an upright position during deployment by use of the boyancy tank and is kept on location away from the area over which it is being deployed by means of an anchor 10.
Next Patent: PREFABRICATED MODULAR HOUSE