A transverse mode ultrasonic probe is provided which creates a cavitation area along its longitudinal length, increasing the working surface of the probe. Accessory sheaths are also provided for use with the probe to enable a user to select from features most suited to an individual medical procedure. The sheaths provide acoustic enhancing and aspiration enhancing properties, and/or can be used as surgical tools or as medical access devices, protecting tissue from physical contact with the probe.

Ultrasonic device for tissue ablation and sheath for use therewith

The invention describes devices for performing thermodynamic work on a fluid, such as pumps, compressors and fans. The thermodynamic work may be used to provide a driving force for moving the fluid. Work performed on the fluid may be transmitted to other devices, such as a piston in a hydraulic actuation device. The devices may include one or more electroactive polymer transducers with an electroactive polymer that deflects in response to an application of an electric field. The electroactive polymer may be in contact with a fluid where the deflection of the electroactive polymer may be used to perform thermodynamic work on the fluid. The devices may be designed to efficiently operate at a plurality of operating conditions, such as operating conditions that produce an acoustic signal above or below the human hearing range. The devices may be used in thermal control systems, such as refrigeration system, cooling systems and heating systems.

Electroactive polymer devices for moving fluid

An ultrasonic medical device comprises an ultrasonic vibration generator that generates vibration along its longitudinal axis. The ultrasonic vibration is transmitted through an ultrasonic coupler and a series of transformer sections that amplify the ultrasonic vibration. A flexible member is coupled to the distal end of the transformer sections, and is thus supplied with a longitudinal vibration at its base by the transformer sections. The flexible member is designed so that it converts the longitudinal vibration into a standing wave that runs along the length of the flexible member. The standing wave produces a series of nodes and anti-nodes along the length of the flexible member. Each of the anti-nodes produces cavitation in fluids in contact with the probe. The cavitation of the fluids causes destruction of adjacent tissue. In this manner, the entire length of the flexible member becomes a working surface that may be utilized for destroying tissue.

Ultrasonic medical device operating in a transverse mode

A fuel pumping apparatus for supplying fuel to an internal combustion engine has a plurality of pumping plungers (19) which are housed in respective bores (17). The plungers are movable inwardly in the bores but during such movement one of the plungers moves to an outer position in which a fuel supply passage (21) which communicates with a fuel supply passage (21) which communicates with a fuel outlet (22) is uncovered to the pump working chamber (20) defined at the inner ends of the bores. Each bore has a supply passage associated therewith. A cam ring (25) is provided to impart inward movement of the plungers and the cam ring is provided with cam lobes (26) on its internal peripheral surface however one of the cam lobes is replaced by a recess which allows the plungers to move outwardly in turn so that fuel is distributed to the outlets which in use are connected to the injection nozzles of an engine.

Fuel pumping apparatus

A system (100) for controlling operational modes of an engine (102) including valve and injection events, in which the engine (102) comprises a plurality of cylinders (104) having an intake and exhaust valve (220, 222), an injector (224), a chamber and an intake and exhaust port. The plurality of cylinders (104) are connected by an intake and exhaust manifold. The system (100) comprises a cylinder control unit (108) for independently governing an operational mode of each of the cylinders. The cylinder control unit (108) comprises a valve control unit for controlling the operation of the intake and exhaust valves. The cylinder control unit (108) also controls opening and closing of the intake and exhaust valves (220, 222) in accordance with the independently governed operational mode of each cylinder. The cylinder control unit (108) further comprises an injector control unit for controlling the operation of each of the injectors (224). The injector control unit controls fuel injection timing of each of the injectors (224), independently of the operation of the intake and exhaust valves (220, 222). The cylinder control unit (108) independently controls each of the cylinders (104) to control the valve and injection events to achieve a plurality of operational modes for the engine (102).

Engine operation using fully flexible valve and injection events

By filling the container of a piezoelectric stack with a dielectric fluid under sufficient pressure, or applying sufficient pressure to a solid dielectric, to maintain dielectric particle velocity and piezoelectric particle velocity substantially spaced, dielectric breakdown with consequent arc over and destruction of the piezoelectric stack is prevented.

Piezoelectric stack insulation

A method and apparatus for achieving optimized efficiency combustion in a diesel internal combustion engine utilizes a cylinder pressure detector which measures peak cylinder pressure relative to crankshaft timing and compares it with a speed-load-timing map comprising several engine parameters including engine speed and engine load in order to compensate for various unknown combustion characteristics of the fuels to be used in compression ignition engines, and automatically adjusts fuel injection timing for optimum efficiency.

Closed loop diesel engine control

A fuel injection system for an internal combustion engine is described, which provides for independent, flexible control of timing as well as quantity of fuel injected. The system is programmable for torque shaping and adaptable to a wide range of engine sizes. It uses piezoelectric valves for controlling injection timing, a shuttle, fuel meter and a gas driven high pressure pump for injecting the fuel into the cylinders.

Fuel injection system for internal combustion engines

A fuel pump for providing fuel at relatively high pressure is activated by gas pressure, created during the compression stroke of an internal combustion engine. The pump includes a piston and a hollow plunger which are biased by a single spring in opposite directions. The piston, which is exposed to gases in the engine's cylinder, is urged, by the gas pressure in the cylinder during the compression stroke, to move upwardly. A limit is placed on the piston's upward stroke. When reaching the upward limit the pressure which is applied to fuel in a fuel chamber is only a function of the force applied by the spring to the plunger. When fuel ejection is enabled, the spring pushes the plunger toward the fuel chamber to eject the fuel therefrom. Toward the end of the exhaust stroke the piston moves toward the engine cylinder, forcing the plunger to move in the same direction until the latter's travel is limited by limiting means. Fuel is then injectable into the fuel chamber for subsequent ejection.

Gas-actuated fuel pump wherein the pump piston is driven by a spring

Apparatus for use with an internal combustion engine wherein a fuel float bowl and gasoline tank are connected through a vapor trap to the ambient atmosphere to prevent pollution by hydrocarbon vapors. The vapor trap is purged at high engine loads by an air flow through the vapor trap and into the engine, the air flow being controlled by the use of a sensor stationed along the path of the fuel or air components prior to their entering the cylinders. In a fuel injection engine of the type wherein fuel pressure varies with engine load, the vapor trap is coupled to a venturi through a valve that is opened only when the fuel pressure exceeds a predetermined value. The valve has a variable opening so that only small amounts of purge air flow through the vapor trap to the engine at moderate engine loads and large amounts of purge air flow only at very high engine loads, to provide a minimal change in the fuel-to-air ratio.

Cormac G. O'Neill

Papers

Piezoelectric stack insulation

Closed loop diesel engine control

Fuel injection system for internal combustion engines

Gas-actuated fuel pump wherein the pump piston is driven by a spring

Vapor venting and purging system for engines