Energy release buoyant actuator

Abstract

A buoyant actuator ( 10 ) is used in apparatus ( 11 ) for harnessing wave energy in a body of water such as the ocean. The buoyant actuator ( 10 ) is deployed within the body of water ( 12 ) and is responsive to wave motion in the body of water. The buoyant actuator ( 10 ) includes a body ( 101 ) incorporating a flow path along which water can flow, and a gate means ( 115 ) for controlling flow along the flow path. The gate ( 115 ) includes closure elements configured as flaps ( 221 ) providing a barrier ( 222 ) across the flow path through the body ( 101 ). Each flap ( 221 ) is moveable into and out of a condition in which it cooperates with the other flaps ( 221 ) to provide the barrier ( 222 ). A latch mechanism ( 231 ) is provided for releasably retaining each flap ( 221 ) in the condition providing the barrier ( 222 ). The latch mechanism ( 231 ) has a magnetic coupling.

1 . A buoyant actuator responsive to wave motion comprising a body defining an interior volume comprising at least one gate means to vary the response of the buoyant actuator to the wave motion. 
     
     
         2 . The buoyant actuator according to  claim 1  wherein the gate means is confined within the interior volume. 
     
     
         3 . The buoyant actuator according to  claim 1  or  2  Wherein the gate means is adapted to permit water to flow through the body of the buoyant actuator. 
     
     
         4 . The buoyant actuator according to  claim 1 ,  2  or  3  wherein the gate means is responsive to a particular sea state. 
     
     
         5 . The buoyant actuator according to any one of the preceding claims wherein the gate means comprises at least one closure element movable between a closed condition which it normally occupies and which impedes water flow through the body, and an open condition in which it permits water flow through the body. 
     
     
         6 . The buoyant actuator according to  claim 5  wherein a releasable coupling is provided for releasably maintaining the closure element in the closed condition, the releasable coupling being adapted to actuate to release the closure element to allow it to move from the closed condition to the open condition to establish the open condition. 
     
     
         7 . The buoyant actuator according to  claim 6  wherein the releasable coupling comprises a magnetic coupling. 
     
     
         8 . The buoyant actuator according to any one of the preceding claims wherein the closure element comprises a flap. 
     
     
         9 . The buoyant actuator according to  claim 8  wherein the flap is pivotally movable between a dosed condition which it normally occupies and which impedes water flow through the body, and an open condition in which it swings outwardly to permit water flow through the body 
     
     
         10 . The buoyant actuator according to  claim 7 ,  8  or  9  wherein the magnetic coupling comprises a magnet means on the closure means adjacent the inner end thereof and a mating part to which the magnet means is magnetically attracted. 
     
     
         11 . The buoyant actuator according to  claim 10  wherein the magnet means comprises an array of permanent magnets accommodated within a housing. 
     
     
         12 . The buoyant actuator according to  claim 11  wherein the housing presents a contact face to confront the mating part of the magnetic coupling, the permanent magnets being recessed with respect to the contact face. 
     
     
         13 . The buoyant actuator according to  claim 12  wherein the housing provides a cushioning portion between the contact face and the permanent magnets. 
     
     
         14 . The buoyant actuator according to any one of the preceding claims wherein the gate means comprises a plurality of closure elements. 
     
     
         15 . The buoyant actuator according to  claim 14  wherein the closure elements are configured to cooperate with each other to provide a barrier across the flow path through the body, each closure element being moveable into and out of a condition in which it cooperates with the other closure elements to provide the barrier. 
     
     
         16 . The buoyant actuator according to  claim 15  wherein the barrier provided by the closure elements extends across the flow path to be substantially normal to the direction of flow of water through the body. 
     
     
         17 . The buoyant actuator according to  claim 14  wherein the barrier is of raked construction such that each closure element when in the closed condition is inclined to the direction of flow of water through the body. 
     
     
         18 . The buoyant actuator according to  claim 17  wherein each closure element is inclined in the direction towards the open upper end of the body. 
     
     
         19 . The buoyant actuator according to any one of the preceding claims wherein the body is configured to have a longitudinal extent and to provide the flow path along which the water can flow though the body parallel to the longitudinal axis of the body. 
     
     
         20 . The buoyant actuator according to any one of  claims 1  to  18  wherein body is of frusto-conical configuration having an upper end, a lower end and a side extending between the two ends. 
     
     
         21 . The buoyant actuator according to  claim 20  wherein the side is of convex shape and bulging at the middle. 
     
     
         22 . The buoyant actuator according to any one of the preceding claims wherein the body is of modular construction. 
     
     
         23 . The buoyant actuator according to any one of the preceding claims wherein the body comprises an inner structure supporting a shell which defines an upper end, a lower end and the side. 
     
     
         24 . The buoyant actuator according to  claim 23  wherein the shell comprises a plurality of sections configured as panels adapted to be connected together. 
     
     
         25 . The buoyant actuator according to  claim 24  wherein each panel is of generally rectangular construction. 
     
     
         26 . The buoyant actuator according to  claim 25  wherein the connections between adjacent panels comprise half lap joints. 
     
     
         27 . The buoyant actuator according to any one of the preceding claims wherein the body is provided with one or more anchoring points to facilitate movement of the buoyant actuator once deployed in water. 
     
     
         28 . The buoyant actuator according to any one of the preceding claims further comprising a dampener for dampening movement of each closure element into the closed condition. 
     
     
         29 . The buoyant actuator according to any one of  claims 15  to  28  wherein the barrier provided by the closure elements extends across the flow path to be substantially normal to the direction of flow of water through the body. 
     
     
         30 . The buoyant actuator according to any one of  claims 15  to  28  wherein the barrier is of raked construction such that each closure elements when in the closed condition is inclined to the direction of flow of water through the body. 
     
     
         31 . A buoyant actuator responsive to wave motion comprising a body incorporating a flow path along which water can flow, and a gate means for controlling flow along the flow path, the gate means comprising a plurality of closure elements configured to cooperate with each other to provide a barrier across the flow path through the body, each closure element being moveable into and out of a condition in which it cooperates with the other closure elements to provide the barrier. 
     
     
         32 . The buoyant actuator according to  claim 31  wherein the barrier is so configured and positioned to be within the confines of the body and wherein the closure elements which remain within the confines of the body even when in the fully open condition. 
     
     
         33 . The buoyant actuator according to  claim 31  or  32  wherein the barrier provided by the closure elements extends across the flow path to be substantially normal to the direction of flow of water through the body. 
     
     
         34 . The buoyant actuator according to  claim 31  or  32  wherein the barrier is of raked construction such that each closure elements when in the closed condition is inclined to the direction of flow of water through the body. 
     
     
         35 . A buoyant actuator responsive to wave motion comprising a body having a support structure adapted to receive a plurality of sections defining a chamber for interrupting water flow through the body, wherein the support structure and plurality of sections are adapted to be transported and assembled in situ. 
     
     
         36 . A buoyant actuator for immersion in a body of water, the buoyant actuator comprising a body defining a hollow interior adapted to receive a volume of water from the surrounding water body, the body having flow control means for controlling flow through the hollow interior, the flow control means having a first condition for blocking or at least impeding fluid flow through the body and a second condition permitting fluid flow through the hollow interior. 
     
     
         37 . The buoyant actuator according to  claim 36  wherein the flow control means are confined within the interior volume. 
     
     
         38 . A buoyant actuator responsive to wave motion comprising a body defining an interior volume, the body comprising an inner structure supporting a shell which defines the inner volume, the shell comprising a plurality of sections configured as panels adapted to be connected together. 
     
     
         39 . A buoyant actuator responsive to wave motion comprising a body defining an interior volume, the body being of frusto-conical configuration having an open upper end, an open lower end and a side extending between the two ends. 
     
     
         40 . A buoyant actuator responsive to wave motion comprising a body incorporating a flow path along which water can flow, and a gate means for controlling flow along the flow path, the gate means comprising a plurality of closure elements providing a barrier across the flow path through the body, the closure elements being moveable into and out of a condition in which it cooperates with the other closure elements to provide the barrier, and latch means for releasably retaining each closure element in said condition, the latch means comprising a magnetic coupling. 
     
     
         41 . A kit for assembling a buoyant actuator according to any one of the preceding claims. 
     
     
         42 . A kit for assembling a buoyant actuator, the kit comprising a support structure and a plurality of sections adapted for connection to the support structure to assemble the buoyant actuator. 
     
     
         43 . A wave energy conversion system comprising at least one buoyant actuator according to any one of  claims 1  to  40 . 
     
     
         44 . A method of harnessing wave energy in a body of water, the method comprising deployment of a buoyant actuator according to any one of  claims 1  to  40  in the body of water. 
     
     
         45 . A buoyant actuator substantially as herein described with reference to the accompanying drawings.