Abstract: This Stirling machine comprises a transfer piston (6, 6a) and a moving part (14) of a generator or of an electric motor, the transfer piston (6, 6a) periodically displacing a working gas between an expansion chamber (VE) and a compression chamber (Vc) which chambers are respectively associated with two working faces of the transfer piston (6, 6a) of which the cross-sectional area ratio ac/aE is >0.35 so that its displacement along an axis X oriented towards the expansion volume (VE) generates an in-phase working gas pressure component Px that opposes the displacement of the piston (6, 6a), so that all of the mechanical energy produced is transmitted to the moving part (14). This machine comprises a resonant second piston (10) coupled to the transfer piston (6, 6a) by a quantity of energy that is proportional to the pressure component Px.

Abstract: This Stirling machine comprises a transfer piston (6, 6a) and a moving part (14) of a generator or of an electric motor, the transfer piston (6, 6a) periodically displacing a working gas between an expansion chamber (VE) and a compression chamber (Vc) which chambers are respectively associated with two working faces of the transfer piston (6, 6a) of which the cross-sectional area ratio ac/aE is >0.35 so that its displacement along an axis X oriented towards the expansion volume (VE) generates an in-phase working gas pressure component Px that opposes the displacement of the piston (6, 6a), so that all of the mechanical energy produced is transmitted to the moving part (14). This machine comprises a resonant second piston (10) coupled to the transfer piston (6, 6a) by a quantity of energy that is proportional to the pressure component Px.

Abstract: A device for producing a rotating flow in a rectangular flow duct which has a flue-gas outlet of an incineration plant, in particular of a garbage incineration plant, and a transition region from a combustion chamber of the incineration plant to the flue-gas outlet. First wall sections on two opposite walls define the flow duct and have a wall width b. The first wall sections have a length l1 of at least approximately 0.4b<0.8b. These first wall sections, with the center longitudinal axis of the flow duct as axis of symmetry, are centrosymmetrically opposite one another and are defined on the one side by the adjacent wall. In the first wall sections, first nozzles for media which can be emitted in the form of a jet are oriented in a row in an injection plane in such a way that they inject a jet into the injection plane, the angle lying in the injection plane between the wall and an injected jet being at least approximately 90°.

Abstract: A method for transmitting mechanical energy between a transfer piston of a Stirling machine and a moveable member of a generator or of an electric motor. A subject of this invention is also a device for implementing this method. The replacing of the driving piston by a completely static pneumatic resonator makes it possible not only to considerably simplify the device, since this method makes it possible to dispense with the driving piston, but also to facilitate the servocontrol as will be explained subsequently. This signifies that not only does the invention make it possible to substantially simplify the device and to reduce the production costs thereof, but also that the reliability of the device is thereby increased. However, for such a device to have an economical benefit, not only must it be possible to produce it at a competitive price, but it must also be capable of operating for many years without requiring any servicing or adjustment.

Abstract: A method for transmitting mechanical energy between a transfer piston of a Stirling machine and a moveable member of a generator or of an electric motor. A subject of this invention is also a device for implementing this method. The replacing of the driving piston by a completely static pneumatic resonator makes it possible not only to considerably simplify the device, since this method makes it possible to dispense with the driving piston, but also to facilitate the servocontrol as will be explained subsequently. This signifies that not only does the invention make it possible to substantially simplify the device and to reduce the production costs thereof, but also that the reliability of the device is thereby increased. However, for such a device to have an economical benefit, not only must it be possible to produce it at a competitive price, but it must also be capable of operating for many years without requiring any servicing or adjustment.

Abstract: Meltblowing apparatus includes electrodes spaced from the meltblowing die discharge and protruding grounded emitters positioned proximate the die discharge. The preferred emitters are in the form of pointed pins spaced along and flanking the die discharge.

Abstract: The percussion mechanism of this device, comprising a cylinder, a free piston, an anvil, a tool holder in which a bundle of needles is disposed, the heads of which are applied to the anvil, is mounted to slide in a tubular housing between two springs used to insulate dynamically the percussion mechanism of the housing and of the handle which holds it. The cylinder is mounted in the housing by a suspension comprising two annular seals and the cylinder is set with a clearance so that the centering provided by the seals insulates mechanically the cylinder of the housing and reduces the transmission of vibrations.

Abstract: A Stirling-cycle assembly comprises an engine with a displacer piston mounted in a cylinder and defining a compression compartment and an expansion compartment respectively of a gaseous working fluid. These compartments communicate via a heat exchanger associated with a hot source, a regenerator and a heat exchanger associated with a heat sink. The engine is coupled to a heat pump having the same structure, via a resonance tube acting as an oscillatory drive member. The displacer piston of the heat pump is associated with a return means, e.g. a rod mounted in sealing-tight relationship in a closedchamber disposed on the compression compartment side.

Abstract: A tennis racket comprises dynamic weights (6) distributed symmetrically relative to the longitudinal axis of the racket between the throat and the transverse axis of the head and suspended by arcuate straps (7) glued to the racket frame (2), the weights being displaceable in a direction perpendicular to the plane of the stringed area (3). The combination of weights and straps is adapted for having an intrinsic vibration frequency about 1.4 to 2 times the fundamental vibration frequency of the racket, such that when the weights are vibrated at their intrinsic frequency (by a ball striking the racket), the vibration of the racket is damped by energy transfer to the weights, and yet energy is also returned to the racket as a reaction in the direction of the ball's flight before the ball leaves the racket. The angular stability of the racket is improved over either fixed weights or dynamic weights having frequencies outside the critical range.

Abstract: A tool for underwater welding comprises an open-mouthed bell with an axially extending electrode inside, part of that electrode being surrounded by a tube supplying gas under pressure from a pumping station floating on the surface. Another tube linking the bell with that pumping station supplies water under pressure to an annular chamber open toward an array of fluid-guiding blades carried by the bell. In one embodiment, the bell is rotatably mounted and carries the blades on its outer surface, being set in rotation by the oncoming flow; in another embodiment, the bell is stationary and the blades are arranged on its inner surface whereby the water swirls in a film along that surface. In either case the circulating water forms a vortex that passes along the bell periphery and around the bell mouth which is slightly spaced from the workpiece to be welded, the resulting centrifugal forces preventing the entry of surrounding water into the bell whereby a gaseous atmosphere is maintained in its interior.

Abstract: A system for measuring the respective volume rates of flow of two components of a composite flow comprises at least two positive displacement pumps such as Moyno pumps connected by a function chamber and having a common drive. The cells of the first pump and the cells of the second pump have predetermined but different volumes of respective cells which travel from the inlet to the outlet of the pump. A sensor is provided for detecting the pressure in the junction chamber.

Abstract: Process and apparatus for accurately measuring the volume or mass flow rate of each component phase of a two-phase mixture. In particular, mixtures of crude oil and natural gas in changing proportions and having fluctuating differential flow velocities are encountered at the wellhead. The volume rate of flow of the oil and gas components are separately determined by temporarily isolating successive fractions of the mixture, determining the component proportions and the volume flow rate of each successive fraction and calculating the product thereof. Mass flow rate may be determined by incorporating the densities of the components into the calculation. Total throughput may be calculated by summing the products of the component proportion and the flow rate for all successive fractions.