Societe Nationale D'etude Et De Construction De Moteurs D'aviation

Michel M Lechevalier

Christian LaCour

Jean-Marie Brocard

Daniel Germain Kettler

Jean-Marie N Pincemin

Xavier J Pasquali

Yves R Berneuil

Christian W Bettremieux

Eddy F Heyden

Christophe N Riou

An apparatus for orienting the forces exerted by a helical coil spring on relatively movable elements is disclosed in which a movable element is movably mounted within a casing so as to move along a movement axis, in which a helical coil spring is interposed between the casing and the movable element so as to exert opposite forces on the casing and the movable element. The lateral forces and the torque forces on the movable element are eliminated by using a swivel joint interposed between the piston and one end of the helical coil spring. The use of the swivel element insures that the force exerted on the movable element by the helical coil spring is coincident with the movement axis of the movable element. A second swivel joint may be utilized between the second end of the helical coil spring and the casing, if desired.

Device for orienting spring forces on relatively movable elements

A differential pressure detector for providing an output pressure modulated as a function of the pressure drop between the pressures upstream and downstream of a fuel metering device, comprising first and second input chambers for connection to said upstream and downstream pressures respectively, a modulated pressure output chamber, a sleeve which is linearly movable in response to changes in the difference between the pressures in the first and second input chambers, and a fixed slide valve which is partly received in the sleeve and which has a bore opening into the output chamber and at least one side port for communicating the first input chamber with the output chamber via the slide valve bore, the aperture of the side port being varied by linear movement of the sleeve to control the communication between the first input chamber and the output chamber. The detector has reduced reaction forces and is particularly suitable for use in a fuel flow regulating system.

Differential pressure detector with reduced reaction forces

An actuating system for a variable area exhaust nozzle is disclosed having inner and outer flaps pivotally connected to an airframe whose positions may be varied by a single set of control cylinders. The control cylinders have a case in which is slidably mounted a pair of pistons, each having piston rods extending from one side, which piston rods extend through one end of the cylinder case. The piston rods may be arranged coaxially to minimize the bulk of the actuating cylinder. One of the piston rods is connected to the inner flaps, while the other of the piston rods is connected to the outer flaps. By selectively supplying pressurized fluid to one or more combinations of a first fluid chamber defined between one of the pistons and an end of the case, a second fluid chamber defined between the two pistons, and a third fluid chamber defined between the other of the pistons and the other end of the case the two piston rods can be made to extend or retract so as to move the inner and outer flaps to desired positions.

Actuating system for a variable area exhaust nozzle

An apparatus for detecting fuel vapors in a turbojet engine oil tank is disclosed which incorporates a device in the oil tank which senses the presence of fuel vapors in the oil tank. The device has a housing defining an inner chamber in which a piston is slidably located. An actuating cartridge is also located in the chamber between an end wall of the housing and the piston. The cartridge comprises a material which expands in volume when subjected to heat and one which produces an exothermic reaction in the presence of fuel vapors. The housing defines one or more orifices to enable the atmosphere within the tank to communicate with the actuating cartridge.

Fuel detector for a turbojet engine oil tank

An adjustment valve is provided with a system able to prevent its piston from jamming. This piston (30) is fitted with a vane wheel (50) placed at its end and receiving a flow of air under pressure. The piston is thus in constant rotation inside the body (20) of the valve. Application is for the injection of fuels in turbojet engines.

Adjustment valve for injecting fuel for a turbojet engine

A pressurized fluid flow regulator for controlling fluid in a fluid circuit is disclosed having a high pressure feed chamber in fluid communication with a source of pressurized fluid and with an exhaust chamber which, in turn, has a fluid outlet connected to the device to receive the pressurized fluid. A first valve controls the flow of fluid between the high pressure feed chamber and the exhaust chamber, while a second valve opens and closes the fluid outlet of the exhaust chamber. The regulator also includes a bypass chamber having an inlet in fluid communication with the high pressure feed chamber and an outlet in communication with the inlet of the source of pressurized fluid. A valve system controls the opening and closing of the bypass chamber inlet such that the inlet is opened when the fluid pressure in the high pressure feed chamber exceeds a threshold value so as to avoid over pressurization of the fluid in the system. The first valve has a valve member slidably located in a valve body of the flow regulator so as to slide along an axis of movement, such relative movement between the first valve member and a cylindrical valve opening serving to regulate the fluid flow between the high pressure feed chamber and the exhaust chamber. The first valve member has a valve surface which extends obliquely to its axis of movement such that such axial movement varies the cross-sectional area of the opening connecting the high pressure feed chamber and the exhaust chamber to thereby regulate the fluid flow between these chambers.

Coaxial pressurized fluid flow regulator

A fluid supply system including a casing having at least one duct extending through it for the passage of fluid and a recess in the casing around the duct or ducts, a cover covering the recess and held against a bearing surface on the casing surrounding the recess, the cover carrying a continuation of the or each duct, and a vent in either the casing or the cover communicating the recess with the environment outside the casing, is provided with a leak tell-tale device for indicating passage of fluid along a path, such as the vent, which, in the event of a leakage of fluid from a duct into the recess, would be followed by the leaked fluid.

Fluid supply system with leak detection device

A detector for detecting the level of oil in an oil reservoir is disclosed having particular application for use in a lubricating system of a gas turbine engine in order to determine a malfunction of an oil-fuel heat exchanger. The device uses an electrically actuated level sensor within the oil reservoir connected to a first electrical circuit having an outlet junction at which is applied a voltage U.sub.1 which varies with the level of oil in the reservoir, and a second circuit having a second outlet junction at which is applied a voltage U.sub.2 which decreases as the oil level decreases, but which does not increase as the oil level increases. A comparison circuit connected to the outlet junctions of the first and second circuits compares the difference between the voltages U.sub.1 and U.sub.2 to a predetermined reference voltage U.sub.0 and, if the difference exceeds this reference voltage, provides an output signal to actuate a visual indicator.

Malfunction detector for an oil-fuel heat exchanger

A valve assembly is disclosed having a valve body with dual valve seats and movable valve member located in the valve body having dual sealing surfaces to bear against the two value seats. One of the valve seats has a sharp-edged configuration which is contacted by a generally frusto-conical sealing surface on a movable primary valve member to crush or break any foreign material in the fluid flow stream. The conical sealing surface and the sharp-edged valve seat also act as a seal to block the fluid flow passageway. A secondary valve member is attached to the primary valve member and has a second sealing surface configured to engage the second valve seat of the valve body. The second valve seat and the second sealing surface may be annular and each have a partially, spherical, cross-sectional configuration. The secondary valve member is connected to the primary valve member such that they may move relatively to each other along their axis of movement. The primary valve member may also be skewed relative to its axis of movement, caused by any foreign particles between the sharp-edged valve seat and the frusto-conical sealing surface without such skewed movement being imparted to the secondary valve member. Thus, even if the primary valve member should be skewed relative to its axis of movement, thereby preventing the first sealing surface from blocking the fluid flow passageway, the sealing surface of the secondary valve member will still contact the second valve seat to block the fluid flow passageway.

Growing community of inventors

Mormant, France

Michel M Lechevalier