Apparatus to convert the energy of waves or swells in the ocean have typically been designed to exploit only the energy of the rising and falling of the swells/waves. However, in a complete cycle of an ocean swell, there is an elliptical movement of the swell whereby there is both an up and down motion and a to and fro (shoreward and seaward) motion. In addition, there is typically motion, for example side to side motion, for reasons such as wind or other weather-related phenomena and the like.
Previous attempts to design an apparatus that harnesses both the in/out and to/fro motion of ocean swells or waves have been disclosed, for example, in US 2009/015013 (Jaer) and U.S. Pat. No. 1,076,844 (Shipman) in order to increase the efficiency or capacity of the energy conversion.
US 2009/015013 (Jaer) discloses a wave power converter for implementation at an offshore location where it will be exposed to passing waves and swell. The converter comprises a buoyancy element placed within a reaction structure so as to move at least vertically relative to the reaction structure, with a force transfer mechanism that connects the buoyancy element to the reaction structure and transfers at least vertical relative motion between the buoyancy element and the reaction structure to a linear energy converting arrangement in the reaction structure. The force transfer mechanism is articulated and configured to transfer compression, tension and shear reactions, but essentially no movements, between the buoyancy element and the reaction structure and at the same time allow limited rotational movements between the buoyancy element and the reaction structure about at least two orthogonal axes (X, Y).
U.S. Pat. No. 1,076,844 (Shipman) provides an ocean wave converter (“wave motor”) comprising a support, a shaft carried thereby, a float, a vane depending below the float, means whereby the center of motion of the float is caused to be below the surface of the water, and means connected with the float to operate the shaft. As disclosed in the patent, this ocean wave converter necessitates a constant mean level of water, and a uniform wave height, and there would not continuously operate in water subject to tides or variable waves.