Abstract: The invention relates to a flow measurement method comprising a generation of successive cycles, each cycle comprising:—a step (35) in which an ultrasonic wave is emitted by a first ultrasonic transducer;—a step (36) in which said ultrasonic wave is received by a second ultrasonic transducer; and—a step (37) in which a propagation time of said ultrasonic wave from the first ultrasonic transducer to the second ultrasonic transducer is measured, the method being characterised in that a given cycle is separated from the preceding cycle by an intercycle duration, and in that a flow rate of the fluid is calculated from a difference between the propagation time of the given cycle and an average of the propagation time measured for the preceding cycle and that measured for the cycle following said given cycle.

Abstract: The invention concerns a flowmeter including a pipe (2) and two ultrasound transducers mounted facing one another and oriented in a measurement direction at a non-zero angle less than 90° to a longitudinal axis of the pipe and including a casing (8) including a main receptacle (9) mounted on said pipe, a first sleeve (10) and a second sleeve (11) extending in a direction orthogonal to the longitudinal axis of said pipe, projecting from a bottom of the main receptacle (9) and on either side of said pipe, each sleeve (10, 11) being configured so as to cover said first or second ultrasound transducer at least partly so as to delimit a receiving internal volume, the main internal volume of the main receptacle being in communication with said receiving internal volumes of said first and second ultrasound transducers. The invention also concerns a method of assembling a flowmeter of this kind.

Abstract: A method is provided for measuring a flow rate of a fluid. The method incudes emitting a periodic signal from a first ultrasonic transductor, where the periodic signal is emitted by the piezoelectric wafer and passes through a liquid media. Unwanted reflections of the periodic signal are delayed so that the first periods of the periodic signal are representatives of the passage measurement. The first periods of the periodic signal are received at a second ultrasonic transductor having a piezoelectric wafer that receives the periodic signal. The flow rate of the fluid is determined by using the first periods of the periodic signal.

Abstract: Disclosed is an ultrasonic transducer including: at least one piezoelectric wafer having two parallel planar main faces: a front face and a posterior face; at least one posterior plate having two parallel planar main faces: an anterior face and a rear face, the anterior face of the posterior plate extending facing, and in contact with, the posterior face of the piezoelectric wafer. The posterior plate has a thickness between three and seven times the thickness of the piezoelectric wafer. The posterior plate has an acoustic impedance between 10 MPa·s·m?1 and 35 MPa·s·m?1. Also disclosed is a method for assembling such a transducer as well as a flowmeter including at least one such transducer.

Abstract: The invention concerns a flowmeter including: pipe (2) for measuring the flowrate of a fluid, said pipe extending along a longitudinal axis (10, 110), a first ultrasound transducer (36, 37) and a second ultrasound transducer (46, 47) are mounted facing one another relative to a wall of said pipe, a first housing (30) and a second housing (40) each delimiting an internal volume to receive said first and second ultrasound transducers, respectively, at least one electronic circuit card (65), a main receptacle (6) to receive said electronic circuit card, a first duct (50) and a second duct connecting the internal volume to receive said electronic circuit card to the internal volumes to receive said first transducer and said second transducer, each duct being formed within the wall of said pipe. The invention also concerns a method of assembling a flowmeter of the above kind.

Abstract: Disclosed is a device for mounting an ultrasonic transducer, suitable for mounting the transducer such that it extends through a wall of a flow meter having a channel in which a fluid flows; the device includes a body in communication with an inner surface of the channel in accordance with a closed contour line that forms an interface between the inner surface of the channel and a surface of the device body, referred to as active surface, which follows the shape of the inner surface of the channel. The active surface extends continuously, and without openings, in the area delimited by the contour line. Also disclosed is a flow meter using a mounting device of this kind.

Abstract: Disclosed is a valve including: a body; a closure member; and a closure member control rod, the control rod extending inside the body at least partially within a fluid flow area. The control rod includes, in the fluid flow area, at least one flowmeter including: a tubular body having two axial ends; a flow measuring device supported by the tubular body and associated with the tubular body so as to enable a flow of fluid flowing outside the tubular body to be measured, and the electrical connection; and an electrical connection extending outside of the tubular body and passing through the tubular body by at least one fluid-tight passage.

Abstract: Disclosed is a device for mounting an ultrasonic transducer, suitable for mounting the transducer such that it extends through a wall of a flow meter having a channel in which a fluid flows; the device includes a body in communication with an inner surface of the channel in accordance with a closed contour line that forms an interface between the inner surface of the channel and a surface of the device body, referred to as active surface, which follows the shape of the inner surface of the channel. The active surface extends continuously, and without openings, in the area delimited by the contour line. Also disclosed is a flow meter using a mounting device of this kind.

Abstract: Disclosed is a valve including: a body; a closure member; and a closure member control rod, the control rod extending inside the body at least partially within a fluid flow area. The control rod includes, in the fluid flow area, at least one flowmeter including: a tubular body having two axial ends; a flow measuring device supported by the tubular body and associated with the tubular body so as to enable a flow of fluid flowing outside the tubular body to be measured, and the electrical connection; and an electrical connection extending outside of the tubular body and passing through the tubular body by at least one fluid-tight passage.

Abstract: Disclosed is an ultrasonic transducer including: at least one piezoelectric wafer having two parallel planar main faces: a front face and a posterior face; at least one posterior plate having two parallel planar main faces: an anterior face and a rear face, the anterior face of the posterior plate extending facing, and in contact with, the posterior face of the piezoelectric wafer. The posterior plate has a thickness between three and seven times the thickness of the piezoelectric wafer. The posterior plate has an acoustic impedance between 10 MPa·s·m?1 and 35 MPa·s·m?1. Also disclosed is a method for assembling such a transducer as well as a flowmeter including at least one such transducer.

Abstract: This device includes an outer casing having: a first tubular zone (16) to the inside of which a finger (4) is fastened; a second tubular zone (40) of larger outside diameter than that of the first tubular zone (16) and extending the first tubular zone (16); and an elastically deformable part (18) of annular shape, extending in a plane transverse to the first tubular zone (16) and connecting the first tubular zone (16) to the second tubular zone (40). The pressure sensor (8) is placed between, on one side, an element (30) integral with the finger and, on the other side, a fixed element (20), called an interface, which is integral with the second tubular zone (40). The interface (20) has an axial contact zone (42) for contact with an element constituting the second tubular zone.

Abstract: This heater plug includes: A tubular body (2), A finger (4) mounted inside the tubular body (2) and protruding outside the body at one extremity of this body, and A pressure sensor (8), A membrane (28) extending between the body (2) and the finger (4) enabling a relative longitudinal movement between the finger (4) and the body (2). The pressure sensor (8) is arranged between firstly a first bearing part (38) connected via a first tubular part (20, 20?) to the finger (4) in the vicinity of the membrane (28) and a second bearing part (40) connected via a second tubular part (22) to the body (2).

Abstract: A glow plug includes: a tubular body (2) having at one of its ends a plug head (10) as well as a zone for being fixed into a bore, an arm (4) mounted on the body (2) of the plug at the end opposite to the plug head (10), and secured to the body (2) in a linking zone (16), an elastically deformable portion (18), located between the linking zone (16) with the arm (4) and the zone fixing the plug body (2), such that the linking zone (16) is mobile and can move longitudinally relative to the so-called stationary fixing zone, and a pressure sensor (8) arranged between an element (30) secured to the linking zone (16) and a fixed element (20) of the plug.

Abstract: A method and a circuit for processing a signal supplied by a piezoelectric sensor (10) indicating the cylinder pressure of a piston engine such as a heat engine. Undesirable variations in the value of the signal supplied by the sensor and corresponding to plateaux in the pressure are compensated by a closed-loop servo control which is suitable for setting an output signal to a predetermined constant reference value, independently of undesirable variations in the signal from the sensor (10). The value of the output signal is sampled, and at each sampling moment, if the absolute value of the variation in the output signal is less than a comparison value, the servo control is kept active. A circuit for processing and a pressure-measuring device including a circuit of this kind is also described.

Abstract: Device for determining an error induced by a high-pass filter in a signal, including a unit (3) for calculating the error according to the formula: E(t)=Ve(t)?Vs(t)=2·?·Fc·??=t0t(Vs(?)? Vs(?))·d?+E(t0) with: E(t) the value of the error induced by the high-pass filter, as a function of the time variable t, ?the trigonometric constant, Fc the cutoff frequency of the high-pass filter, t0 the initial instant, ?integration variable, Ve the signal input to the high-pass filter, Vs the signal output by the high-pass filter, Vs the mean value of the signal Vs. A method of correcting the error induced is also presented and applicable to the error correction of a piezoelectric pressure sensor.

Abstract: This heater plug includes: A tubular body (2), A finger (4) mounted inside the tubular body (2) and protruding outside the body at one extremity of this body, and A pressure sensor (8), A membrane (28) extending between the body (2) and the finger (4) enabling a relative longitudinal movement between the finger (4) and the body (2). The pressure sensor (8) is arranged between firstly a first bearing part (38) connected via a first tubular part (20, 20?) to the finger (4) in the vicinity of the membrane (28) and a second bearing part (40) connected via a second tubular part (22) to the body (2).

Abstract: A device includes a pressure sensor (11-13) for measuring pressures inside the combustion chamber of a cylinder in an internal combustion engine. The device includes: an outer body (1); a lug (5) extending partially into the combustion chamber; an inner housing (14) inserted into the body and surrounding an upper portion of the lug, the housing being secured to the lug and to the body and having an elastically deformable portion (17) between the two securing areas, characterized in that the housing (14) is secured to the body (1) at a securing area (18) extending in the upper portion of the body.

Abstract: Device for measuring cylinder pressure of an internal combustion engine includes a pressure sensor that includes a piezoelectric element associated with a capacitive element, and an output generating a first voltage representative of the cylinder pressure. A filtering module of the device filters parasitic low-frequency voltages and generates a second voltage free of these parasitic voltages. A control module delivers a control signal that is dependent on a switching parameter correlated with a stroke. A switching module, in response to the control signal, disconnects the input of the filtering module from the output of the pressure sensor during the first stroke and connects the input of the filtering module to the output of the pressure sensor during the second stroke. The first stroke corresponds to a compression stroke or to a combustion-expansion stroke, and the second stroke corresponds to an intake stroke or to an exhaust stroke.

Abstract: The spark plug comprises: —a central electrode (2), —an insulating core (6) bearing the central electrode (2), —an external body (8) in which the insulating core (6) is mounted and which has a region (18) where the external body (8) is crimped onto the insulating core (6), and—a force sensor (30). The force sensor (30) is mounted at the periphery of the external body (8) between, on the one hand, a bearing element (38) secured to a first peripheral region of the external body (8) and, on the other hand, a second peripheral region (24) of the external body (8). The second peripheral region (24) of the external body (8) is further away from the crimping region (18) than the first peripheral region. The bearing element (38) is prestressed against the force sensor (30).

Abstract: A method and a circuit for processing a signal supplied by a piezoelectric sensor (10) indicating the cylinder pressure of a piston engine such as a heat engine. Undesirable variations in the value of the signal supplied by the sensor and corresponding to plateaux in the pressure are compensated by a closed-loop servo control which is suitable for setting an output signal to a predetermined constant reference value, independently of undesirable variations in the signal from the sensor (10). The value of the output signal is sampled, and at each sampling moment, if the absolute value of the variation in the output signal is less than a comparison value, the servo control is kept active. A circuit for processing and a pressure-measuring device including a circuit of this kind is also described.