FR3058202B1 - TAP FOR FLUID TANK AND BOTTLE COMPRISING SUCH FAUCET - Google Patents

Abstract

Valve comprising a withdrawal circuit (3) comprising a member (4) for regulating the flow rate and / or pressure, a control member (5) for the regulating member (4) mounted for rotation around an axis (A) of rotation on the valve (1) and cooperating with the regulating member (4) to control the flow rate and / or the pressure depending on the position of the control member (5), the valve (1) ) comprising a device (9) for detecting the position of the control member (5) comprising at least one mobile magnetic element (12) integral with the control member (5) and a fixed mounted magnetic sensor (15). on the valve, the movable magnetic element (12) is arranged on the control member (5) to generate a magnetic field without symmetry of rotation about the axis (A) of rotation of the control member (5) regardless of the position of the control member (5) around the axis (A) of rotation, the magnetic sensor (15) is configured and intended to measure the value of at least one characteristic of the magnetic field relative to a measuring reference frame of the sensor (5), said characteristic comprising at least one of: the angle of the magnetic field, at least one spatial dimension of the magnetic field

Description

The invention relates to a valve for a fluid reservoir under pressure and a bottle comprising such a valve. The invention more particularly relates to a valve for a fluid reservoir under pressure comprising a body housing a withdrawal circuit comprising an upstream first end intended to communicate with a fluid storage volume under pressure and a second downstream end intended to be connected to a user organ of the gas withdrawn, the withdrawal circuit comprising a regulating member of the flow rate and / or the pressure of the fluid withdrawn between the upstream and downstream ends, the valve comprising a control member, in particular a manual control member, of the regulating member , the control member being rotatably mounted about an axis of rotation on the body of the valve and cooperating with the regulating member to control the flow rate and / or the fluid pressure allowed to flow from the upstream end. towards the downstream end according to the position of the control member with respect to the body, the valve comprising a device for detecting the position of the control member, the detection device comprising at least one movable magnetic element integral with the control member and a magnetic sensor fixedly mounted on the body of the valve. The invention relates in particular to valves equipped with a rotary gas flow selector (for example, a flywheel positioning a barrel with calibrated or setting holes for a needle) and an onboard electronics performing a calculation, a recording or a transmission requiring knowledge of the selected rate.

To realize such a detection of the position of the flow selector a known solution consists in providing a mechanical element integral with the rotary selector cooperating with a mechanical element of a sensor integral with the frame of the bottle, with respect to which the rotary selector rotates. For example, the rotary selector axis activates a potentiometer or an incremental angle counter. According to another configuration, the axis, the periphery or a face of the selector is provided with cams actuating in their passage contactors fixed on the frame.

Alternatively, the rotary selector shaft is provided with a groove or spiral allowance, transforming the rotary motion into a linear motion detectable by a linear displacement sensor. According to another possibility, a face of the rotary selector is provided with a circular groove of variable depth, or of a variable and circular excess thickness, transforming the rotary movement into a linear motion detectable by a linear displacement sensor

These solutions can pose problems of play, mechanical resistance to shocks and aging, and cost (especially to be compatible with a limited space available on the bottle).

When in particular the axis of rotation of the selector is traversed by a gas outlet pipe (see for example FR3012196A1), the elements of the mechanism must be deported, which may lead to the use of gear trains and to accentuate the issues raised above.

These solutions may require good control of the mechanical play between the cylinder frame and the selector. On the other hand, they can be parasitized by nearby masses or in contact. They do not make it possible to start or stop the position detector when the selector leaves or goes through a reference position.

According to another known possible solution for detecting the position of a rotary selector, one or more permanent magnets are placed on the flow selector and interact with magnetic field sensitive elements placed on the frame of the bottle.

In general, the magnet is circular or annular, with diametric magnetization, and the axis of rotation coincides with the axis of symmetry of the magnet. Similarly, the sensor is centered on the axis of rotation, at a maximum distance of typically five mm from the magnet.

These solutions are poorly suited in particular in the case of the position detection of a rotary selector in which the detection system is offset relative to the axis of rotation of the selector.

The misalignment of the sensor or magnetized elements can cause an alteration of the relationship between the angle of the selector and the magnetic field measured by the sensor. This can make the determination of the angular position of the ambiguous selector impossible.

In addition, the induced increase in the distance between the magnet and the sensor decreases the intensity of the magnetic field at the sensor, with possible effects: insufficient field to sensitize the sensor, and field variations depending steering wheel position lower than the sensor resolution.

An object of the present invention is to overcome all or part of the disadvantages of the prior art noted above. To this end, the valve according to the invention, furthermore in accordance with the generic definition given in the preamble above, is essentially characterized in that the movable magnetic element is arranged on the control member to generate a magnetic field without symmetry of rotation around the axis of rotation of the control member regardless of the position of the control member about the axis of rotation, and in that the magnetic sensor is configured and intended to measure the value of at least one characteristic of the magnetic field relative to a measurement reference frame of the sensor, said characteristic comprising at least one of: the angle of the magnetic field, at least one spatial dimension of the magnetic field.

Furthermore, embodiments of the invention may comprise one or more of the following features: the magnetic sensor is spaced from the axis of rotation by a distance of between 5 mm and 45 mm and preferably between 10 and 30 mm; mm, in a direction parallel to the axis of rotation of the control member, the magnetic sensor is spaced from the movable magnetic element by a distance of between 5 mm and 50 mm and preferably between 15 and 30 mm, magnetic sensor is a three-dimensional magnetic sensor measuring the three components of the magnetic field in space, - the magnetic sensor is a sensor for measuring the angle of the magnetic field in a determined measurement plane, - the axis of rotation of the control member is not parallel to the measuring plane of the magnetic sensor, - the magnetic element comprises two discrete magnets angularly offset in relation to the axis of r otation, - each magnet comprises a north pole and a south pole defining a direction of rectilinear magnetization and in that the magnetization directions of the two magnets are inclined with respect to the axis of rotation, - the directions of magnetization of the magnets each form an angle with the axis of rotation between 30 and 60 degrees and preferably 45 degrees, - the magnetization directions of the two magnets are reversed, that is to say that one of the magnets has its own north pole facing the axis of rotation while the other magnet has its south pole turned towards the axis of rotation, - the two magnets are located at a distance identical or distinct from the axis of rotation of the body of rotation. control and between 10 and 40 mm and preferably between 15 and 35 mm, - the magnetic element comprises a single magnet defining at least one north pole and at least one south pole, - the valve comprises an electronic acquisition member of storage and data processing, in particular an integrated circuit and / or a microprocessor and in that the detection device is connected to said electronic element, the magnetic sensor converts the measured value of the characteristic of the magnetic field into a determined direct or digitized electrical signal , for example an electrical voltage, said electrical signal being transmitted to the electronic data acquisition and data acquisition member and in that the control member is movable in a plurality of determined distinct positions in which the measured values of the characteristic of the magnetic field are distinct and are converted into respective separate electrical signals, - the electronic storage acquisition and data processing element stores or associates a plurality of predetermined distinct electrical signal values to a plurality, respectively. predicted distinct positions determined from the control member so as to determine the position of the control member from the electrical signal of the measured value of the magnetic field, - the electronic storage acquisition and data processing element is configured to compare the electrical signal of the measured value of the magnetic field with the plurality of predetermined individual electrical signal values and for detecting and possibly quantifying and / or signaling a defective measured value of the measured magnetic field when the electrical signal of the measured value of the magnetic field does not does not correspond to the plurality of distinct electrical signal value ranges determined, - the valve comprises an electronic data indicating device (s) relative to the fluid content in a bottle intended to be connected to the tap, the electronic indication device comprising the acquisition member storage and data processing and at least one data display connected to the data storage and data acquisition member, the position sensor is connected to the data acquisition and data acquisition member to transmit to the latter a signal representative of the flow rate and / or the fluid pressure imposed by the regulating member, the data storage and processing acquisition member being configured, in response to the reception of this signal of flow rate and / or imposed pressure, for controlling the display on the display of relative flow information and / or the fluid pressure imposed by the regulating member and / or the operating mode of the tap and / or the contents of the bottle, - in the vertical position of use of the valve, the vertical distance between the magnetic sensor and the plane (preferably horizontal) containing the axis of rotation of the control member is included between 0 and 10 mm and preferably equal to 5 mm, - the two magnets are arranged diametrically opposite to the axis of rotation of the control member, - each magnet comprises two poles (north and south) located from and else of a central point or center, - each magnet is of parallelepipedic type and with dimensions: length, width and thickness between respectively 15 and 60mm; 5 and 20mm, 1 and 10mm, - each magnet is covered with a corrosion-resistant layer, - the magnetic sensor also measures the intensity of the magnetic field, - in the vertical position of use of the valve, the angle between the measurement plane of the magnetic sensor with the horizontal plane containing the axis of rotation between -90 ° and +55 degrees and preferably the measuring plane of the magnetic sensor is at an angle of between 25 and 35 degrees with the horizontal plane containing the axis of rotation. rotation and in that the measuring plane of the magnetic sensor is oriented towards the control member, the magnetic element comprises a single annular magnet arranged concentrically around the axis of rotation of the control member, said magnetic element being diametrically magnetized that is to say having its north and south poles respectively formed by two portions of the ring, the magnetic annular magnet is bent in at least one of s ring strings, - the magnetic element comprises a part arranged around the axis of rotation of the control member and comprising two distinct portions having respective respective magnetizations. the magnetic element comprises a plastic part comprising ferromagnetic elements and / or a ferromagnetic part comprising zones of distinct magnetizations; the magnetic element comprises one or more point magnets integrated in a support forming a magnetic circuit; is constituted at least in part by a material with high magnetic permeability, - the control member is movable between a first "closure" position in which the control member has the regulating member in a closed configuration the first withdrawal circuit and a plurality of second positions called "opening" in which the control member has the regulating member in respective opening configurations of the first withdrawal circuit to allow fluid to flow from the upstream end to the downstream end with a flow rate and / or a determined, when the magnetic sensor detects that the control member is in its first closed position, the electronic storage acquisition and data processing member interrupts the power supply of at least one electrical device member electronic data indication (s) and in that when the magnetic sensor detects that the controller is in at least one of the second open positions, the electronic storage acquisition and processing member of data restores the power supply of at least one electrical element, - the control member (manual or motorized) is movable in a plurality of distinct positions corresponding to respective flow and / or pressure settings imposed by the regulating device in the circuit, the detection device is electrically powered, the valve comprising a supply source electrical ion connected to said detection device, - the magnetic sensor is configured or driven by the electronic storage acquisition and data processing device to perform measurements periodically with a controlled variable frequency, including a first high frequency in a time interval following a detection of a passage of the control member from the first position to a second position and a second reduced frequency lower than the first frequency after a determined time interval and / or when the pressure measured by a pressure sensor in the bottle detects a pressure below a determined threshold, that is to say that the measurement of the first sensor can be clocked differently depending on the time and / or the situation: a relatively fast response time when the tap is opened, then relatively less often when the measured pressure indicates e an empty bottle for example, - the measuring frequency is reduced when it is detected a return of the control member in its position corresponding to a closure of the circuit.

Preferably, the magnetic element comprises two north poles and two south poles. The invention also relates to a bottle or a set of pressurized fluid bottles comprising such a valve. The invention may also relate to any alternative device or method comprising any combination of the above or below features. Other features and advantages will appear on reading the description below, with reference to the figures in which: - Figure 1 shows a front view, schematic and partial, illustrating a valve mounted on a pressurized gas cylinder according to a possible embodiment of the invention, - Figure 2 illustrates, schematically and partially, the structure and operation of a portion of the valve of Figure 1, in particular a position detection device of a selector; - Figure 3 shows a side view, schematic and partial, illustrating another example of the structure and operation of a position detection device of a selector of a valve, - Figure 4 shows a view of schematic and partial face, illustrating the example of structure and operation of the position detection device of FIG. 3; FIG. 5 schematically illustrates e t, an example of a measurement curve of a sensor of the detection device according to the angular position of the control member, - Figure 6 illustrates, schematically and partially, the structure and operation of a part of the valve of FIG. 1, - FIGS. 7 to 11 represent symbolic representations of examples of characteristics of the magnetic field measured by a device according to the invention with, where appropriate, detection intervals of corresponding positions of the FIGS. 12 to 15 show perspective, diagrammatic and partial views respectively illustrating four distinct embodiments of the magnetic element; FIGS. 16 and 17 are schematic and partial side views respectively illustrating two other variants; different embodiments of the magnetic element integrated in a tap.

The valve 1 illustrated in the figures conventionally comprises a body housing a withdrawal circuit 3 comprising a first upstream end 13 intended to communicate a fluid storage volume under pressure (the inside of at least one bottle 2 for example) and a second downstream end 23 to be connected to a user organ of the gas withdrawn (for example oxygen for a patient, a fan, a mask or any other device).

The withdrawal circuit 3 comprises a member 4 for regulating the flow rate and / or the pressure of the fluid drawn between the upstream and downstream ends 13. This regulating member 4 may comprise a flow and / or pressure regulator comprising, for example, For example, a valve, a system of calibrated orifices or any other suitable device.

The valve 1 comprises a member 5 for manual control (and / or motorized) of the control member 4, that is to say a selector operable manually or remotely.

Conventionally, the control member 4 is mounted movably relative to the valve body 1, for example in rotation, and cooperates with the regulating member 4 to control the flow rate and / or the fluid pressure allowed to flow from the end 13 upstream to the downstream end 23 according to the position of the control member 5 relative to the body. That is to say that the position of the selector 5 modifies (mechanically and / or electrically and / or pneumatically and / or hydraulically) the regulation of the flow rate or of the gas pressure in the circuit imposed by the regulating member 4 .

The valve 1 further comprises an electrical device 9 for detecting the position of the control member 5 (see FIGS. 2 and 6 in particular). For this purpose, the valve 1 may comprise a supply source 7 connected to said detection device 9 (and possibly other electrical devices). The power source 7 comprising, for example, an electric battery, a photoelectric cell or any other suitable device.

The detection device 9 comprises at least one movable magnetic element 12 integral with the control member 5 and one (preferably single) magnetic sensor fixedly mounted on the valve body.

According to an advantageous feature, the movable magnetic element 12 is arranged on the control member 5 to generate a magnetic field without symmetry of rotation about the axis A of rotation of the control member 5, whatever the position of the control member 5 around the axis A of rotation. In addition, the magnetic sensor is configured to measure the value of at least one characteristic of the magnetic field with respect to a measurement frame, said characteristic comprising at least one of: the angle of the magnetic field, at less a spatial dimension of the magnetic field.

Preferably, said at least one characteristic comprises at least one of: - the angle of the magnetic field, - the angle of the magnetic field and at least one spatial dimension of the magnetic field, - at least two spatial dimensions of the magnetic field according to non-parallel directions.

This relative configuration of the magnetic element 12 and the magnetic sensor 15 allows a perfect measurement of the position of the control member 5, even in case of misalignment between these different elements, especially when the active center of the magnetic sensor is not not located on the axis A of rotation of the control member 5.

The sensor 15 is sensitive to the field at the magnetic field (and can be conventionally associated with an electronic card for conditioning and processing). "Without rotational symmetry" means that there are no two positions of the control member in which the same value of the characteristic of the magnetic field is measured. In other words, according to this arrangement, there is always at least one choice of characteristic of the magnetic field such that there are not two positions in which the same value of the characteristic is measured.

This avoids ambiguity of measurement.

By "spatial dimension" is meant, for example, the value of at least one component of the magnetic field in a measurement reference frame of the sensor 15.

Preferably, said magnetic field thus has an axial axis A asymmetry, that is to say an antisymmetry with respect to the axis A of rotation of the control member.

Also preferably, this magnetic field has no invariance by rotation along this axis A of rotation of the control member other than by a rotation of 360 °.

Likewise, preferably, this magnetic field has no plane of symmetry or antisymmetry to which this axis A would be normal.

Preferably, this or these characteristics of the magnetic field are verified on the field generated by the magnetic element 12 in the vacuum (that is to say without taking into account possible field distortions caused by the elements of the bottle on which are This means that the claimed geometry defines a magnetization for easy unambiguous detection.

Preferably, the elements of the bottle on which the valve is mounted, the other corresponding parts, and generally the elements of any neighboring bottles, are made of non-magnetic materials or low magnetic permeability. By "neighboring" is meant, for example, the elements inscribed in a sphere of radius 5 cm centered on the active center of the sensor 15. By weak magnetic permeability, it is understood, for example, less than ten times that of the air.

In the example of FIGS. 2 to 4, the magnetic element 12 comprises or consists of two permanent magnets 12. The two magnets 12 (which may be parallelepipedal) are magnetized according to their thickness defining for each a direction 121, 221 of magnetization (or magnetization vector) rectilinear along the axis north pole-south pole.

In the nonlimiting example of Figures 3 and 4, the two magnets 12 are positioned so that the segment connecting the center of the two magnets 12 passes through the axis A of rotation of the control member 5.

In addition, the plane defined by the axis A of rotation and the center of one of the magnets 12 preferably contains the magnetization vector of the two magnets 12.

Moreover, by considering a vector colinear with the axis A of rotation, the scalar products of this vector and the magnetization vectors of each magnet 12 are of opposite signs. That is, the two magnets 12 have opposite north / south orientations (the north pole of one of the magnets 12 is oriented towards the valve while the north pole of the other magnet is oriented towards the outside of the faucet).

This configuration makes it possible in particular to generate a magnetic field without symmetry of rotation along the axis of rotation A of the control member 5.

For example, the magnets 12 are identical parallelepipeds, for example of dimensions 40 mm × 10 mm × 5 mm, or 20 mm × 10 mm × 5 mm.

For example, the magnets 12 are made of neodymium-iron-boron, in one piece or mixed with a polymer or the like, and optionally covered with an anticorrosive layer.

The centers of the two magnets 12 may be equidistant or not from the axis A of rotation of the steering wheel, for example at a distance of 26 mm.

The lines 121, 221 carrying the magnetization vectors of the magnets 12 can be cut on the valve side where the magnetic sensor is located. These directions 121, 221 can form with the axis A of rotation an angle 18, 19 of 45 ° for example.

However, the lines carrying the magnetization directions 121 and 212 do not necessarily cut the axis A of rotation of the control member 5. These lines 121, 221 may for example pass in front or behind being a little inward or outward relative to the vertical sectional plane of FIG.

Preferably, the magnetic sensor is a three-dimensional magnetic sensor measuring the three components of the magnetic field in space. That is, the sensor 15 measures both the orientation of the magnetic field in its active plane, or in space and its intensity. Such a sensor 15 may be of the type designated by the reference TLV493D-A1B6 of the company Infineon. That is, the magnetic sensor measures or determines the vector representative of the magnetic field in a determined frame of reference.

By measuring both the orientation of the magnetic field in the active plane of the sensor and its intensity, or by measuring the magnetic field in space (its three components), it is thus possible to associate with a field measurement a position of the control member 5 among a set of discrete positions. That is to say that this configuration makes it possible to obtain a relationship that is almost affine, possibly in pieces, and in any case bijective, between the value of the characteristic of the magnetic field measured by the sensor 15 and the position of the organ 5 command, expressed by its angle (modulo 360 °).

This is shown diagrammatically in FIG. 5: at each angle in degree (°) (position) AS of the control member 5 is associated a value (for example in degree °) measured AM by the magnetic sensor.

This is illustrated symbolically also in Figures 10 and 11.

Figure 10 illustrates trace 120 of the magnetic field vector in the measurement plane of the sensor 15 in a two-dimensional mark for a 360 degree rotation of the control member.

The sensor 15 may be a sensor measuring, according to an active measurement plane 115 and according to a reference X1, Y1, the angle of the magnetic field and the intensity of the projection of the magnetic field in this active plane 115.

When the control member completes a rotation, the trace 120 may have the shape illustrated in FIG.

Specific points 50 of this trace 120 may correspond to determined (eg stable) positions of the control member.

For each point 50, it is possible to define a neighborhood 150 (for example a disc centered on each reference point 50).

These neighborhoods 150 are preferably disjoint. When the measured value 51 of the magnetic field arrives in a neighborhood it is possible to determine that the control member 5 is in said corresponding position 50. In the event of a disturbance (symbolized by the vector 52), the value 510 (resulting vector) is outside the neighborhoods 150. The disturbance may be considered too important and the position undetected or non-compliant. The device may generate, for example, a fault mode (sending an alert message, switching to a default position, for example, etc.).

The disturbances considered may be related to the use of the device in a hospital environment (for example, magnetic disturbances generated by the vicinity of an MRI or other medical devices). The disturbances can also be generated by permanent magnets present in telecommunications devices (walkie-talkie speakers, etc.) and in their shells, as well as the disturbances generated on the device by the vicinity of a similar device.

Figure 11 illustrates the same principle in a three-dimensional repository X1, Y1, Z1.

In this possible variant embodiment, the magnetic sensor does not measure only the angle of the magnetic field in a plane and the intensity of its projection in this plane, but it measures the orientation in the space of the magnetic field and its intensity. That is, the sensor measures both the orientation in the space of the magnetic field, and its intensity. It is then possible to associate with a field measurement a position of the control member among a set of discrete positions with a neighborhood approach in space.

The active plane of the magnetic sensor is for example provided with a three-dimensional mark X1, Y1, Z1. As before, reference points 50 are predefined on the trace 120 (corresponding for example to determined stable positions of the control member). Neighborhoods 150 (spheres centered on points 50), preferably disjoint, are predefined.

When the measured value of the angle (vector for example) is in a neighborhood 150 it is possible to determine that the control member 5 is in said corresponding position 50. As previously, in case of disturbance (resulting vector is out of neighborhoods), the disturbance may be considered too important and the position not detected or non-compliant.

Referring again to FIGS. 3 and 4, it is possible to define an OXYZ mark as follows: - the origin O corresponds to the projection of the center of the magnets 12 on the axis A of rotation of the control member 5 - the X axis is on the axis of rotation A, oriented towards the valve, - the Y axis is oriented from the origin O towards the center of one of the magnets 12, - the Z axis is built to form an orthogonal reference.

The projection of the center of the magnets 12 on the axis A of rotation and the projection of the active center of the sensor 15 on the axis A of rotation of the flywheel are preferably distant about 16 mm. This corresponds to their spacing along the X axis. The definition of the marker is preferably made with the control member 5 (and therefore the magnets) in an arbitrary reference position (see for example the figures).

The distance between the active center of each sensor 12 and the axis A of rotation (according to Y) is preferably equal to 20 mm.

The distance between the active center of each sensor 120 and the vertical plane defined by the X and Y axes is preferably 5 mm.

Of course these distances are not limiting and can be adapted (for example more or less 5 to 20mm for example, including more or less 10mm).

In another possible embodiment, the sensor 15 measures for example only the angle of the magnetic field.

For example, the magnetic sensor measures only the angle formed by the projection of the magnetic field on its active plane (i.e., its determined measurement plane) with a reference axis.

This type of sensor 15 is for example a sensor type AAT003 sold by the company "NVE Corporation" or a KMA36 sensor from the company "Measurement Specialties".

Preferably, the active plane 115 (measurement plane) of the sensor 15 forms with the horizontal plane defined by the X and Y axes an angle 16 of thirty degrees.

This angle value is not limiting, this angle 16 may be for example between -90 ° and 55 °. The intersection of this horizontal plane and the measurement plane 115 of the sensor 15 is preferably in the direction of the control member 5. (For example, 0 ° = horizontal, direction 115 points to the left in Figure 3, + 90 ° = vertical, direction 115 points down in the figure, -90 ° = vertical, direction 115 points towards the top of the figure).

In this case where the magnetic sensor is a sensor for measuring the angle of the magnetic field in a measurement plane 115, this measurement is preferably made with respect to a direction determined on the plane 115 defining the zero angle. Preferably this angle measurement is made in a specific direction to define the increasing or decreasing angles.

Figure 4 illustrates the arrangement of Figure 3 seen in a direction parallel to the axis X of the marker. D denotes the transverse distance between on the one hand the vertical plane OXY defined by the centers of the magnets 12 and the active center of the sensor 15. H denotes the vertical distance between the XOZ plane and the active center of the sensor 150. Again this configuration makes it possible to obtain an almost affine relation, possibly in pieces, and in any case bijective, between the value of the characteristic of the magnetic field measured by the sensor 15 and the position of the control member, expressed by its angle (modulo 360 °)

In particular, this makes it possible to obtain a bijective relation between the angle of the control member with respect to a reference position and the projection angle of the magnetic field measured on the active plane 115 of the sensor relative to to a reference axis of the sensor.

This is shown schematically in Figure 5; at each angle (position) AS of the control member 5 is associated a measured value AM by the magnetic sensor. Knowing the relation between the measured value AM and the angle AS of the control member 5 makes it possible to unequivocally detect the angular position of the control member from the value measured by the magnetic sensor. That is, the variation of the value measured by the sensor 15 depends only on the variation of the angular position of the control member (and not on the position around which the variation is made). In other words, the range of variation of the output value of the magnetic sensor is used (eg equitably) to distinguish the different angular positions of the control member. In particular, this ensures a robustness of the position detection, vis-à-vis external disturbances, equal for all possible positions of the control member 5.

For example, twelve distinct angular positions of the control member can be predetermined (separated by 30 ° each).

The quasi-affine relation illustrated in FIG. 5 can have an offset 155 that is quasi-constant with respect to the theoretical curve 55 passing through zero. This offset 155 can be corrected by redefining the zero degree reference (0 °) in the electronics processing the output value of the magnetic sensor.

Figure 7 schematically another way of estimating the angular position of the control member 5 from the measurement of the magnetic field angle (including measurement of the angle of the vector of the magnetic field by the sensor 15).

The measurement plane 115 of the magnetic sensor may be provided with a mark defined by the axes X2 and Y2.

The trace 120 of the (vector) magnetic field in the measuring plane 115 of the sensor 15 (when the control member performs a complete rotation) may be unknown when only angles of the magnetic field are measured by the sensor 15.

Two positions or points 50A, 50B respectively corresponding to two successive positions of the control member 5 are separated by a determined angle 250. It is thus possible to calculate or measure this angle 250 separating two embodiments of the vector of the magnetic field 4 and 5.

Similarly, it is possible to measure or calculate the angle 251 separating two other points 50B, 50C (other embodiments of the magnetic field vector).

For a given point 50B (determined position) it is possible to define an angular sector 252 bounded for example by the bisectors of the two previously defined angles 250 and 251 which surround this point 50B.

In case of disturbance of the magnetic field, for a given measured magnetic field angle θ (given embodiment of the magnetic field vector), it is possible to estimate that the position of the control member corresponds to the adjacent position 50B in the case where the detected angle 50B is in the angular sector 252 associated with said position 50B.

Without this being illustrated in the figures, it is possible to determine angular sectors that are disjoint and smaller than those defined by the bisectors described above. The measurement of an angle outside the angular sectors thus determined would be associated with the existence of a disturbance invalidating the measurement. As previously described, this may trigger the passage of the system into a fault mode.

Figure 8 schematizes another possible mode of detection of undesirable disturbances.

As before, it is possible to define or measure the trace 120 of the magnetic field vector in the measurement plane of the sensor 150 (plane defined by the axes X2 and Y2) when the control member 5 performs a complete rotation. It is possible to define a neighborhood 150 around this trace 50 for example bounded by an expansion and contraction of the trace 50 relative to the origin O of the marker.

In the case of measurement of a magnetic field (magnetic field vector) 51, it is possible to consider that there is a too great perturbation if the measured value 51 is outside this vicinity 150.

In this case, the electronic device associated with the sensor 15 may, for example, be configured (programmed) to generate in this case a fault mode (sending of an alert message, toggling on a position of the control member 5). ). In the example shown in FIG. 8, the measured value 53 is in the vicinity 150. The angle of the magnetic field can be measured by the magnetic sensor. Thus, the angular position of the control member 5 can be detected via the value of the measured angle.

FIG. 9 describes another detection mode with the determination if necessary of undesirable disturbances.

As before, when the control member 5 completely rotates the trace 120 of the magnetic field vector in the plane of the sensor is known (mark defined by the axes X2, Y2, Z2). It is possible to predefine a neighborhood 150 around this trace. The neighborhood 150 is for example bounded in space by a tube centered on the trace 120.

Alternatively, and as illustrated in FIG. 11, for example when the detail of the trace 1 is not predefined or known in detail between two or more reference points (reference positions), it is possible, for example, to define a neighborhood 150 by the volume 126 interpolated between surfaces 226, 326 predefined for points (positions) of reference.

For a measured value 53 of the magnetic field (magnetic field vector for example), it can be considered that there is a too great disturbance if the measurement is outside the vicinity 150. In this case the electronic device associated with the sensor 15 can adopt a default mode (send warning message, switch to a default steering position ...). In the opposite case (measurement in the predefined neighborhood), the electronics associated with the sensor 15 can directly use the measured values of the magnetic field to deduce the angular position of the control member 5 (for example via a predefined model of the relation between the measured angle and the corresponding position).

When it has not been detected excessive disturbance it may be possible to project the three-dimensional image of the magnetic field detected in a plane and use the methods described above in relation to Figures 8 and 10 .

In another embodiment, the aforementioned characteristics of the generated magnetic field are obtained via another geometry of the magnetic element 12.

For example, the symmetry of the scalar intensity field of the magnetic field can be broken by changing the position of the center of one of the magnets 12 and / or by changing the orientation of one of the magnets 12 with respect to its position and / or by changing its orientation according to the previous embodiments.

For example, it is possible to shift the position of the center of one of the magnets 12 by plus or minus ten millimeters along the line joining the centers of the magnets 12 in their reference positions above.

In this way, the reference position of the control member 5 (corresponding for example to the position giving a zero flow rate) can be characterized in a unique way, in that in this reference position, at least one of the intensity of the magnetic field; a value of the magnetic field in a spatial direction is greater than the values noted for the other positions of the control member.

In this case, the detection of the reference position can therefore be performed by directly comparing the single intensity of the magnetic field or a single value of the magnetic field in a spatial direction, at a determined threshold.

In one possible embodiment, the device thus determines whether the selector is in its reference position or not, without having the device electronics perform the trigonometric operations necessary for the 2D or 3D representation of the magnetic field described above ( which operations consume energy).

In another embodiment an electric contactor can be provided in addition. This contactor can be on the body of the valve for example and can be actuated by the magnetic field of the magnetic element 12. This contactor can be dimensioned and placed on the tap so that it activates only when the intensity of the The magnetic field that it receives is greater than a determined threshold, for example only in one or more specific positions of the control member 5 (and in particular in a reference position corresponding for example to a zero flow).

In another possible embodiment, the magnetic element 12 in the form of two magnets 12 can be replaced by a single magnetic part providing a similar magnetic field distribution.

For example, the magnetic element 12 comprises or consists of a permanent magnet of annular shape, diametrically magnetized and having determined dimensions (outer diameter, inner diameter, thickness).

As illustrated in Figure 14, the magnet 12 can be bent along some of its ropes (for example in two opposite ropes) to reproduce the inclination of the two magnets 12 described above.

This annular magnet 12 may consist for example of a plastic part (polymer in particular) in one piece, closed or not, and having two distinct regions in which the plastic is loaded or covered with ferromagnetic elements, in the manner magnets. This may be, for example, a polymer bonded structure ("polymer bonded"). These two magnetized zones can have the same geometry and the same direction of magnetization as the two permanent magnets 12 described above. See also the embodiments of Figures 12 and 13. This magnetic element 12 preferably has a diametrical magnetization defining north poles 123 and 124 south (see Figure 14).

In the example of FIG. 12, the open magnetic element 12 may have in a plastic matrix (polymer) two inclusions made of ferromagnetic and polymer materials, each having a magnetization according to their thickness defining a south pole 124 and a north pole 123.

In the example of FIG. 13, the annular magnetic element forms a closed frame. In this body (polymer for example) are also provided two inserts ferromagnetic material each having a magnetization according to their thickness defining north poles 123 and south 124.

In another possible embodiment, and as illustrated in FIG. 15, the magnetic element 12 may be an integral ferromagnetic piece, closed or not, in which a magnetization distribution is created during manufacture. For example the magnetization is created according to the "Polymagnet" technology of the company "Correlated Magnetics". This magnetization is distributed on the magnetic element 12 to reproduce a field according to the above characteristics (approaching, for example, a magnetization produced by the two permanent magnets with north poles 1323 and south 124 as above).

According to a possible advantageous feature, this magnetic element 12 ring-shaped (open or closed) may constitute or be part of a rotating wheel forming the control member 5.

In a possible variant, the device may comprise two magnetic sensors.

In another possible embodiment illustrated in FIG. 16, the magnetic element comprises or consists of two point magnets integrated in a part 220 with high magnetic permeability. This piece 220 with high magnetic permeability is preferably provided to form a magnetic circuit. As illustrated, this magnetic element can be housed in the control member 5 (rotary wheel in particular) and can form an air gap on the side of the valve body or the bottle. The air gap forms for example a break in the magnetic circuit to allow the case where to place a magnetic sensor in the lines of magnetic fields spanning (or extending) in the gap.

Preferably, the dimension of the gap in a horizontal direction (perpendicular to the plane of the figure) is as large as the geometry of the control member 5 allows.

The magnetic field lines 222 created are channeled and projected toward the valve body (on the bottle side) toward the magnetic sensor. This piece 220 incorporating the two magnets 12_may be a ferromagnetic piece in one piece, closed or not, in which a magnetization distribution may have been created during manufacture. For example the magnetization is created according to the "Polymagnet" technology of the company "Correlated Magnetics". This magnetization can be distributed on the magnetic element to reproduce a field according to the characteristics described above (approaching, for example, a magnetization carried out by the two permanent magnets with north poles 123 and south 124 as with reference to the examples below. above).

As illustrated, the magnetic circuit (part 220) can be pierced with a channel 223 or passage. This channel 233 may coincide with the axis A of rotation of the control member 5. This channel 223 may, where appropriate, make it possible to house therein functional elements of the valve and in particular of the gas circuit, for the passage of, for example, gas (see, for example, document FR3012196A1: a gas outlet connection may open through of the control member 5).

FIG. 17 illustrates an alternative embodiment of the embodiment of FIG. 16 with a single magnet 12 in the magnetic circuit 220.

As before, the magnet 12 is spaced apart from the axis A of rotation of the control member 5 which carries it. The invention applies to the case of a manual control member 5 but can also be applied to the case of a remotely controlled control member 5, for example via a remotely controlled motor. In this second case the detection device can provide a return value for the remote control or servo for the engine.

The travel of the control member 5 can be unlimited or limited. For example in the case of a rotary control member it is preferably limited (rotation less than 360 °).

The electrical signal generated by the sensor 15 representative of the measured characteristic (angle of the field for example) may be an analog value, a digital coding, a byte or any other appropriate signal (direct or digitized electrical signal).

For example, with a KMA36 type sensor mentioned above, a possible encoding of the angle of the measured magnetic field may consist in generating a signal comprising a high state and a low state, of determined total duration (for example 125 ms), wherein the angle is encoded by the position (in time) of the rising or falling edge of the signal. It should be noted that for the different configurations described above using neighborhoods 150, the definition of the neighborhoods used can be carried out a priori, for example on the basis of a numerical model of the theoretical trace of the magnetic field, or by calibration ( one or more times in the life cycle of the device), for example, for each position, by memorizing the realization of the magnetic field detected by the sensor to define the center of the neighborhood.

The device may advantageously include a clock estimating the time elapsed since it was put into service and making it possible to vary the reference trace of the magnetic field, and / or the position of the neighborhood centers, and / or the neighborhoods as a function of time. That is to say that the reference trace of the magnetic field, and / or the position of the neighborhood centers, and / or the neighborhoods vary, for example, as a function of the variation of the magnetization of the magnets according to time.

For example, the device can apply a homothety of ratio A to the initial position of the neighborhood centers, where A is equal to (1-B) multiplied by the elapsed time (estimated / measured by the clock). With B being the natural decay rate of magnet magnetization over time, for example B = 0.2% per year. Other models of decay of magnetization as a function of time, for example logarithmic, can be envisaged.

See, for example, the publication Magnetization Losses in Sintered NdFeB Permanent Magnets With Time, Haavisto and Paju (Magnet Technology Center, Prizztech Ltd., Pori, Finland) or the publication "Time-dependent DEMAGNETIZATION IN SINTERED NdFeB MAGNETS", HAAVISTO AND PAJU, Proceedings of 20th International Workshop on Rare Earth Permanent Magnets and Their Applications, Bled, Sept. 2010.

The bottle using the device can also integrate a flowmeter or a device for measuring the remaining capacity, making it possible to access an estimate E1 of the average output flow rate of the gas over a time interval. Independently, knowledge of the estimates of the positions of the flow selector over time makes it possible to access a second estimate E2 of the average output flow rate of the gas over the same time interval. The device may go into a fault mode and / or trigger a calibration loss alert when a significant difference (eg greater than 10%) is found between the two estimates in one or more measurement pairs {E1, E2 }.

Claims (16)

A valve for a fluid reservoir under pressure comprising a body housing a withdrawal circuit (3) comprising an upstream first end (13) for communicating with a pressurized fluid storage volume and a second downstream end (23) for to be connected to a user organ of the gas withdrawn, the withdrawal circuit (3) comprising a member (4) for regulating the flow rate and / or the pressure of the fluid withdrawn between the upstream (13) and downstream (23) ends, the valve (1) comprising a member (5) for controlling, in particular manual control member (4), the control member (5) being rotatably mounted about an axis (A) of rotation on the body of the valve (1) and cooperating with the regulating member (4) to control the flow rate and / or the fluid pressure admitted to circulate from the upstream end (13) to the downstream end (23) according to the position of the control member (5) relative to the body, the valve ( 1) comprising a device (9) for detecting the position of the control member (5), the detection device (9) comprising at least one mobile magnetic element (12) integral with the control member (5). and a magnetic sensor (15) fixedly mounted on the valve body, characterized in that the movable magnetic element (12) is arranged on the control member (5) to generate a magnetic field without rotational symmetry around the axis (A) of rotation of the control member (5) irrespective of the position of the control member (5) around the axis (A) of rotation and in that the magnetic sensor (15) is configured and intended to measure the value of at least one characteristic of the magnetic field with respect to a measurement reference frame of the sensor (5), said characteristic comprising at least one of: the angle of the magnetic field, at least one dimension of the magnetic field and in that the magnetic sensor (15) is a three-dimensional magnetic sensor measuring the three components of the magnetic field in space. 2. Tap according to claim 1, characterized in that the sensor (15) is spaced apart from the axis (A) of rotation by a distance of between 5mm and 45mm and preferably between 10 and 30 mm. 3. Tap according to claim 1 or 2, characterized in that, in a direction parallel to the axis of rotation (A) of the control member (5), the magnetic sensor (15) is spaced from the element (12) movable magnetic with a distance of between 5mm and 50mm and preferably between 15 and 30mm. 4. Tap according to any one of claims 1 to 3, characterized in that the sensor (15) is a magnetic sensor measuring the angle of the magnetic field in a measurement plane (115) determined. 5. Tap according to claim 4, characterized in that the axis (A) of rotation of the control member (5) is non-parallel to the measurement plane (115) of the sensor (15) magnetic. 6. Tap according to any one of claims 1 to 5, characterized in that the element (12) comprises two magnetic magnets (12) discrete disposed angularly offset about the axis (A) of rotation. 7. Tap according to claim 6, characterized in that each magnet (12) has a north pole and a south pole defining a rectilinear direction of magnetization (121, 221) and in that the magnetization directions of the two magnets ( 12) are inclined with respect to the axis of rotation (A). 8. Tap according to claim 7, characterized in that the magnetization directions (121, 212) of the magnets (12) each form an angle (18, 19) with the axis of rotation (A) between 30 and 60 degrees and preferably 45 degrees. 9. Tap according to any one of claims 6 to 8, characterized in that the magnetization directions of the two magnets (12) are reversed, that is to say that one of the magnets (12) has its north pole facing the axis (A) of rotation while the other magnet (12) has its south pole facing the axis (A) of rotation. 10. Tap according to any one of claims 6 to 9, characterized in that the two magnets (12) are situated at a distance identical to or distinct from the axis (A) of rotation of the control member (5). and between 10 and 40 mm and preferably between 15 and 35 mm. 11. Tap according to any one of claims 1 to 5, characterized in that the magnetic element comprises a single magnet (12) defining at least one north pole and at least one south pole. 12. Tap according to any one of claims 1 to 11, characterized in that the valve (1) comprises an electronic member (17) for storage acquisition and data processing, including an integrated circuit and / or a microprocessor and in that the detection device (9) is connected to said electronic member (17). Valve according to Claim 12, characterized in that the magnetic sensor (15) converts the measured value of the characteristic of the magnetic field into a determined direct or digitized electrical signal, for example an electrical voltage, the said electrical signal being transmitted to the sensor. electronic storage acquisition and data processing device (17) and in that the control member (5) is moveable in a plurality of predetermined distinct positions in which the measured values of the magnetic field characteristic are distinct and are converted into respective separate electrical signals. Valve according to claim 12 or 13, characterized in that the electronic data storage and processing acquisition device (17) stores or associates a plurality of predetermined separate electrical signal values respectively with a plurality of predetermined distinct positions of the control member (5) so as to determine the position of the control member (5) from the electrical signal of the measured value of the magnetic field. Valve according to any one of claims 12 to 14, characterized in that the electronic data acquisition and data acquisition device (17) is configured to compare the electrical signal of the measured value of the magnetic field with the plurality of predetermined distinct electrical signal values and for detecting and possibly quantifying and / or signaling a defective measured value of the measured magnetic field when the electrical signal of the measured value of the magnetic field does not match with the plurality of value ranges of distinct electrical signals determined. 16. Bottle of fluid under pressure characterized in that it comprises a valve according to any one of claims 1 to 15.