Ocean Power Technologies, Inc.

General Electric Company

Other

David B Stewart

James S Gerber

George W Taylor

James E Eder

Henry I Schanzer

Thomas Sabol

Robert Louis Steigerwald

John Norton Park

George David Goodman

Gulcharan Singh Brainch

Timothy J Liska

Todd Stephen Heffron

Paul J Smalser

William Ross Miller

William Blaine Powers

Richard W Albrecht

Frances M Stewart

James Gerber

Apparatus attached to the flared open end of a wind instrument includes one or more layers of particle filtering materials for preventing the dispersion of pathogens from the wind instrument while enabling sound transmission with little muffling and distortion, and minimal resistance for the musician.

Protective device minimizing dispersion of airborne pathogens from wind instruments

A wave energy converter (WEC) buoy includes at least one pitch-driven WEC ('PDWEC') device. Each PDWEC device includes two reaction masses which are placed at diametrically opposite ends of a container designed to float along the surface of a body of water and to move in response to the pitching motion of the waves. The reaction masses are interconnected so that when one reaction mass moves up, the diametrically opposed reaction mass moves down, and vice-versa. The movement of the reaction masses drives power take off (PTO) devices to produce useful energy. The reaction masses may be interconnected by any suitable linking system. One or more PDWEC device may be combined with a heave responsive device to produce a WEC buoy which can produce a power output in response to pitch or heave motion.

Pitch and heave driven wave energy converter system including cable supported reaction masses

The generally up and down movement of a reaction mass is converted into rotary motion which is used to drive a rotary hydraulic spring comprised of a rotary hydraulic pump motor and an accumulator to produce a 'spring' function. The invention is particularly applicable to wave energy converters (WECs) having a reaction mass which needs to be coupled to a spring to ensure its oscillation and to cause it to be centered about its center of travel. The linear up-down motion of a reaction mass may be converted via a linear-to-rotary translator to rotary motion to drive a rotary hydraulic pump/motor so as to provide spring action to the reaction mass and ensure its oscillation and proper positioning.

Wave energy converter with rotary hydraulic spring

Apparatus for connecting a power cable to a marine vessel which is subject to pitch, heave, roll and yaw motion includes a ball and socket device for decreasing the twisting and bending of the power cable. The socket is attached to the vessel and the ball can rotate freely Within the socket but its up down motion is restricted. The power cable's outer protective sheath is attached to the ball while its conductors pass through the ball and are connected to an internal connector. A flexible cable (wire) is connected between the internal connector and electrical equipment internal to the marine vessel.

Ball and socket power cable connector

A reaction mass and a spring are configured to form an 'oscillator'. The reaction mass is coupled to, and can wrap around, a first pulley via a first belt/cable. The spring is coupled to, and can wrap around, a second pulley via a second belt/cable. The first and second pulleys are mechanically linked together and are mounted so they rotate in tandem. The diameter of the second pulley is different than the diameter of the first pulley to cause the reaction mass to travel a different distance than the spring in response to the up down motion of the reaction mass. The first and second pulleys may be circular with the second pulley being made smaller than first. Alternatively, the first pulley may be circular and the second pulley a cam of varying radius.

Reaction mass and spring oscillator for wave energy converter

A wave energy converter (WEC) system includes WEC devices which can function to produce useful energy (power) efficiently in response to heave motion and/or pitch motion and/or roll motion. Pitch responsive devices are deployed around the outer periphery of a container and one (or more) heave responsive device is located about the center of the container. The pitch responsive devices may be of the type defined as PDWECs which include two reaction masses which are primarily operable in response to pitching motion or they may be of the type which includes one reaction mass operable in response to pitch and/or heave motion.

Multi-mode wave energy converter devices and systems

A wave energy converter (WEC) includes a float tending to move in phase with the waves, a spar tending to move out of phase with the float and power take off device (PTO) coupled between the float and spar for converting their relative motion into useful energy. The PTO includes a rack and pinion mechanism which drives a high-torque, multi-pole, permanent magnet generator (PMG) to produce electrical signals of relatively high frequency relative to the frequency of the waves and the basic motion of the rack and pinion mechanism. In accordance with one aspect of the invention, the rack and pinion mechanism may be located within the spar which may be hermetically sealed by a sealing mechanism which allows a thrust rod coupled between the float and spar to move up and down with little friction to ensure efficient operation. In addition, a braking arrangement is provided for inhibiting relative motion between the float and spar during extreme severe wave conditions. In this way, the pinion gears and generators need only be sized for the operational wave conditions.

Wave energy converter and power take off system

A wave energy converter (WEC) system includes a shell containing an internal oscillator comprised of a reaction mass suspended from the shell by an elastic spring in parallel with a constant force spring. The constant force spring provides a relatively constant force (Fc) to counterbalance the static weight of the reaction mass and reduce the extension 'static' length of the elastic spring while the elastic spring exerts a force (F) on the reaction mass that is proportional to the displacement, x, of the elastic spring. A power take-off (PTO) device, located within the shell, coupled between the shell and the internal oscillator converts their relative motion into electrical energy.

Wave energy converter with internal mass on spring oscillator

A wave energy converter (WEC) for converting energy contained in surface waves on a body of water to useful energy comprises two floats movable relative to one another in response to passing surface waves. Both floats comprise expandable outer envelopes which have been expanded into full and firm shape. In one process, expansion is obtained by filling the floats with fluids, for example, air and water. The fluids can be pumped into the floats, or the floats can be mechanically expanded in the presence of the fluids for self filling owing to pressure differentials. In one embodiment, a float envelope can comprise of plurality of end to end connected length sections in nested or telescoped relationship. Expansion is obtained by pulling the telescoped sections out from one and other, for example, by pumping fluids into the telescoped sections.

Expandable wave energy conversion system

A wave energy converter (WEC) includes a shell suitable for being placed within a body of water. The shell contains an internal oscillator comprising a 'reaction mass' and a spring mechanism coupled between the reaction mass and the shell. The shell and internal oscillator are constructed such that, when placed in a body of water and in response to waves in the body of water, there is relative motion between the shell and the internal oscillator's mass. A power take-off (PTO) device is coupled between the internal oscillator and the shell to convert their relative motion into electric energy. In systems embodying the invention, the spring mechanism is designed such that its displacement or movement is less than the displacement or movement of the reaction mass. The spring mechanism may be any device which enables the reaction mass to undergo a given replacement while its displacement or movement is less than that of the reaction mass. This property enables the size of the WEC to be more readily controlled (e.g., made smaller).

Wave energy converter utilizing internal reaction mass and spring

A linear electric generator (LEG) includes sections of coils of an induction coil assembly (ICA) disposed along a distance dand apparatus for passing a permanent magnetic assembly (PMA) of length d, where dis less than d, along the coils for generating voltages and power in the coils in close proximity to the PMA. Unidirectional conducting elements are connected between the coils and output power lines to couple the voltages developed across excited coils to the output power lines without the unexcited coils loading down or dissipating the voltage developed across the output power lines.

Circuitry for increasing efficiency of a linear electric generator

In a linear electric generator (LEG) which includes apparatus for passing a permanent magnetic assembly (PMA) along linearly disposed sections of coils of an induction coil assembly (ICA) for generating voltages and power, a switching arrangement for coupling only selected sections of coils of the ICA across the power output lines of the LEG. The selected coil sections include the sections of coils of the ICA in close proximity to the passing PMA. In accordance with different embodiments, the non selected coils of the ICA may be either short circuited or disconnected (open circuited) from the power output lines.

Coil switching circuit for linear electric generator

An electric generator includes multiple coil sections and switches connected to the multiple coil sections for selectively interconnecting the coil sections in series, or in parallel, or in a series-parallel configuration across first and second power terminals for producing a controlled AC voltage across these power terminals. The electric generator, with its multiple coils and interconnecting switches permitting reconfiguration of the coils, enables systems subjected to widely varying conditions and forces, such as a wave energy converter (WEC), to be operated with increased efficiency. The generator may also include multiple windings which can be selectively interconnected into a wye or a delta configuration to also control the output voltage produced by the generator and increase the efficiency of the power conversion system, particularly at low values of voltage.

Coil switching of an electric generator

An ocean wave energy converter (WEC) utilizes the relative motion between permanent magnet and induction coil assemblies to generate electricity. The permanent magnet assemblies and induction coil assemblies are separately housed in watertight enclosures, enabling a wide range of wave energy converter configurations, nearly unlimited stroke and obviating the need for a common magnet/coil enclosure with seals. The magnet assemblies are constructed with surface or buried magnets. The wave motion moves a magnet assembly relative to a stationary coil assembly, or vice versa. Either the magnet assembly or the induction coil assembly are made long enough to provide the generation of electricity over a desired operational range of travel. Various means are provided to maintain the spacing ('gap') between the magnetic and coil assemblies relatively constant.

Wave energy converters (WECs) with linear electric generators (LEGs)

A WEC system embodying the invention includes a column and shell, arranged to move relative to each other, and a lever-like apparatus having an input end and an output end and an intermediate point, between the two ends, the intermediate point being rotatably connected to the column. The input end is connected to the shell and moves at the same velocity and in the same direction as the shell. The output end moves in the opposite direction and at a rate which is a multiple of the shell velocity. The multiple being a function of the ratio of the length of the intermediate point to the output and input ends. In systems embodying the invention, one of two components (a PMA or an ICA) of a linear electric generator may be attached to the shell and the other of the two components may be attached to the output end of the lever-like apparatus to produce high relative velocity between the two components resulting in higher amplitude and higher frequency output voltages.

Growing community of inventors

Cranbury, NJ, United States of America

David B Stewart