FR2659413A1 - Ultra-quick stopper, particularly for medical use - Google Patents

Abstract

Ultra-quick stopper, particularly for medical use. The stopper is composed of a body enclosing a stopper chamber (2) into which there emerges a connection pipe (3), stopped off at its internal end by an ultra-quick electromagnetic stopper, the coil (19) of which is powered at rest in slight repulsion, then in attraction operation, by the discharge of a capacitor. This invention is of particular interest to the industries of medical diagnostic equipment.

Description

 The present invention relates to a device for ultra-rapid obturation of a conduit provided in particular for a chain of diagnostic and respiratory measurements in the medical field.

 Of course, other ultra-fast flow shutter applications are targeted by the invention, in particular those located in the industrial field.

 For various reasons, in particular of a medical nature, there is a need, in the context of general medical examinations, to have at least one indication of the air resistance of the airways because, if a resistance value considered as normal is characteristic of a state of good health, conversely it gives useful indications on the respiratory disorders from which a patient suffers.

 Thus, one of the non-limiting applications of the ultra-rapid obturation device for a conduit according to the invention, in the medical field, relates to the implementation of the method for evaluating the resistance of the bronchial tree by interruption flow.

 Among the various existing methods intended to provide a measurement value representative of the resistance of the upper pulmonary airways, the present invention provides effective and suitable means for the so-called "flow interruption" method.

 The principle of this method was imagined in 1927 by MM. VON NEERGARD and WIRZ then developed by them for its application in the medical field.

 This method has been improved and various variants and refinements make it more meaningful and more precise.

 According to the basic principle of application of this method, it is sufficient, in order to determine approximately the resistance of the pulmonary tracts, to interrupt for a short period of time the gas flow and to measure the oral pressure representing the alveolar pressure and the instantaneous flow. at the time of closing.

 Unfortunately, due to the lack of high-performance equipment, and due to the technical implementation difficulties in acquiring and using the pressure signal, this method has not produced the expected practical application results.

 Fortunately, recent technical and technological advances have revealed, through new possibilities, an emerging and important attraction for the implementation of this method which becomes interesting because of the additional possibilities and the ease of use conferred by the new technologies.

 In addition, the IT tool brings new perspectives in the exploitation of the signal collected.

 The principle of this method consists in closing, for a short time interval, the upper airways. The value of the instantaneous flow at the time of closure and that of the pressure during this occlusion make it possible to measure the value of the alveolar pressure and to determine by calculation from a measurement-extrapolation the resistance of the respiratory tract.

 This information is very useful in establishing a diagnosis necessary for the appearance of respiratory disorders or simply as a test or screening.

 Fundamentally for the quality of the measurement, the shutter must be performed without any mechanical disturbance.

Thus, special precautions are necessary with regard to filling. It must be rapid and silent, triggered without the subject's knowledge, independent of pressure or mechanical effects.
clean shakes with no rebound effect.

 It will be understood that any conventional mechanical flap or flap system used in the field of fluid mechanics cannot be suitable, even because of the excessive inertia and the parasitic pressures associated with the closure.

 In addition, the use of articulated closing flaps generates fluid flow disturbances, consecutive to their size and to the non-symmetrical closing mode.

 These disturbances significantly distort the measurements and make these devices unattractive.

 To obtain the best possible signal form, the time required for closing must be reduced to a minimum value and, desirably, for the necessary significant character of the measurements, be situated below a threshold of 5 milliseconds.

 However, this value is difficult to achieve with a movable mechanical or electromechanical equipment, conventional or improved, intended to ensure a temporary seal in the flow of a pressurized fluid.

 The object of the present invention is to remedy these various drawbacks by proposing a high-speed shutter enabling total occlusion to be achieved in the shortest possible time, without causing disturbances detrimental to the quality and accuracy of the measurements. .

 To this end, it relates to a shutter consisting of a body containing a shutter chamber into which opens a connection conduit closed at its inner end by an ultra-fast electromagnetic shutter, comprising a disc with axially magnetized core, the coil is supplied at rest with slight repulsion then in attraction control by the discharge of a capacitor.

 The numerous advantages of the invention are specified below without limitation.

The compactness of the device constitutes a
of the main advantages.

The valve is permanently pushed back by a magnet
constant contrary guaranteeing safety in
opening.

. It is possible to change the moving part between
each patient due to the ease of dismantling
all.

. The closure is ultra-fast and perfectly
waterproof.

. The switch is easily miniaturizable for a
infant application.

The whole is heated and thermostatically controlled to avoid
ter any moisture deposits inside
the device.

. The coil simultaneously performs all three functions
following
- it constantly pushes the valve
- she attracts him during the occlusion
- it contributes to the heating of the device
- it is waterproof to allow disinfection
fection of the device.

The device fulfills all the conditions
hygiene.

. The magnet used in this valve is covered with a
easily cleanable and disinfectable material. It can trigger shutter at any time
both in inspiration and in expiration.

The technical characteristics and other advantages of the invention are recorded in the description which follows, given by way of nonlimiting example in one embodiment with reference to the accompanying drawings in which - Figure 1 is a schematic sectional view of
the ultra-fast shutter according to the invention - Figure 2 is the power and communication diagram
electrical control - Figure 3 is a sectional view of a variant
dual two-way super-fast shutter
according to the invention - Figure 4 is a median cross-sectional view
according to line IV-IV of Figure 3 - Figures 5 and 6 are schematic views, res
pectively in cross section and in plan, of a
non-guided free valve variant in one case
of application to a track - Figure 7 is a schematic view of a variant with
free valve not guided in application in an organ
of the three-way valve type - Figures 8 and 9 are comparative curves of
pressure variations between a device
non-damped slow valve shutter (Figure 8) and
the device according to the invention (Figure 9) with in
overloads the layout of the curve above.

 It was found that a total duration of keeping the valve closed on the order of 70 milliseconds in no way hampered the patient.

 In any case, this should not exceed 150-200 milliseconds so as to avoid voluntary reactions by the patient which would disturb the measurement.

 The object of the present invention is to allow extremely rapid closing of a conduit from an external control. According to an application in the medical environment, it makes it possible, in an extremely short time, to close the duct and to interrupt the respiratory flow for the production of an ultra-rapid respiratory obturator for buccal exit, the closing time of which is situated below the 50 millisecond threshold indicated above.

 It is intended to serve as a sensor to a set of fully automated and computerized diagnostics and measurements making it possible to automatically determine, in addition to the resistance of the airways, the spirometric characteristics of the patient.

 In other fields, all the applications requiring extremely rapid closure of a pipe in a gas flow are possible, thanks to the invention.

 The ultra-fast shutter according to the invention consists of the following general means.

 A hollow body 1 delimiting a sealing chamber 2 constitutes a portable sensor intended to interrupt the respiratory flow of the patient for a short period of time.

 The hollow body has on the one hand a connection conduit, for example buccal 3, extending inside by a projection 4 and outside by a birth 5 on which is mounted a nozzle 6 provided disposable for obvious reasons hygiene and, on the other hand, to a rear outlet 7 communicating with a flow measurement unit 8 comprising a flow sensor 9 and various elements specific to this measurement.

 The shutter chamber 2 contains a shutter mechanism 10 with valve 11 intended to mechanically shut off the communication between the buccal connector 3 and the shutter chamber 2 for a short period of time.

 According to the variant shown in FIG. 1, the closure element of the valve 11 is shaped according to a movable disc 12 extended by a guide rod 13 moving along a cylindrical housing 14.

The disc 12 is a part made of plastic material into which is inserted a core constituted by a strong permanent magnet 15 with axial magnetization.

 Thanks to the reduced dimensions of the closure part, and especially of its rod, the inertia of the moving assembly turns out to be low. Thus, the movements of this closure part are extremely rapid.

 It abuts abruptly against the internal orifice 16 of the buccal conduit 3 situated opposite which it opens into the sealing chamber.

 In order to cancel or at least greatly reduce the mechanical rebound phenomena, the front face of the disc 12 is provided with a pad 17 formed of a thickness of dense foam absorbing vibrations. In addition, the plane of the orifice 16 is lined with an O-ring 18 made of rubber intended to ensure an immediate seal and to further improve the damping of the rebound.

 The disc 12 with permanent magnet is actuated in displacement by a coil 19 designed and produced for the production of an axial magnetic field of attraction of great value.

 The electromagnetic field produced generates significant forces which allow rapid movements.

 The coil 19 is mounted for example on the inner projection 4 of the buccal conduit 3.

 In order to allow the measurement of the pressure during occlusion, a pressure tap 20 opens into the buccal conduit 3. It communicates with a suitable pressure sensor CP located in the handle 21 where the other electronic measurement circuits are housed and CEMC.

 The coil 19 is controlled by the electrical circuit shown in Figure 2 from the computer of the ORD diagnostic station.

 In this figure we notice, in general, that the coil 19 is electrically controlled by the discharge of a capacitor C charged by a DC high-voltage source from a discharge relay RDD, putting the capacitor in the circuit of discharge through the coil 19. The relay RDD is controlled by an external circuit and its rest position closes on the coil 19 a source of direct current of reverse polarity SR generating, in the coil, a continuous field of repulsion now at rest the valve disc away from the coil.

 The RDD discharge relay is activated from a CV locking circuit, for example with an optoelectronic relay RO, the command of which comes from the computer of the diagnostic station ORD. It records, manages, presents and interprets the measurement data of the direction and the intensity of the flow supplied by the sensor (s) of the flow unit and the measurement data of the pressure sensor CP.

 Two important variants are shown in Figures 3, 4 and 5. It is on the one hand a shutter device with double valve and on the other hand a free valve device without guide.

 It should be recalled here that the ultra-fast shutter device described above is independent of its field of application. Protection therefore extends to the most diverse fields of application, for example industrial, medical and domestic or any other.

 The first version concerns a double valve shutter device.

 It is a three-way device including two air channels 22 and 23 selectively closed and one outlet channel 24.

 It comprises a body 25 with a central chamber 26, for example cylindrical, open at its two opposite ends which are, for example, inlet ends, and a transverse conduit 27 situated for example in the middle part of the lateral surface which constitutes, in the majority of cases, an outlet end 28.

 This transverse conduit 27 opens into the central chamber 26 through an orifice 29 in line with a guide support 30 on which is slidably mounted a movable assembly 31 forming a double valve constituted by two mechanically paired closure elements, such as for example discs 32 and 33 each similar to disc 12 already described above, that is to say plastic parts, with a core 34 or 35 axially magnetized, each covered with a pad 36 or 37, absorbing shocks.

 These discs are mechanically paired by a guide rod 38 allowing the mobile assembly 31 to slide in a mechanical movement back and forth transversely to the guide support 30.

 On the opposite ends of the body are mounted end caps such as 39 and 40 each followed by a coil such as 41 and 42 each fitted on its front face with an O-ring seal such as 43 and 44.

 The guide support for example assumes a shape of a circular sector profile 45 immobilized by screws such as 46, 47, 48, such as for example those shown in FIG. 4, leaving an inlet and communication recess 49 in the chamber central to the right of the inlet opening of the transverse duct 27.

 The operation is identical to the simple version.

 The attraction is carried out on the mobile assembly of the double valve causing a shutterliberation movement of the inlet or outlet channels in the manner of a hydraulic distributor drawer.

 According to a variant with low inertia, the movable part 50 for closing the valve is entirely free inside a holding cage 51, for example with a grid 52, as shown in FIGS. 5 and 6. This is by example of a part affecting the general shape of a disc. This contains, as before, an axially magnetized core 53 which is pressed very quickly against the opening to be closed, located in front of or behind a coil 54.

 It will be understood that, in this version without guide rod, the mobility of the closure part is even greater due to its mechanical non-subjection during movement.

 Many other applications of the ultra-rapid device according to the invention, in its variant form described above, prove to be possible since the selective obturation of one or the other of the channels of a valve-type member. three-way (Figure 7) until the realization of a multi-way distributor with one way selectively closed.

 This organ of the three-way valve type comprises a body 55 in "Y", for example with two inlets 56 and 57 and an outlet 58. On each of the channels is provided a valve 59, 60 formed of a closed coil 61, 62 selectively by a single closing piece 63, constituted by a disc with an axially magnetized core evolving in a holding cage 64.

 All these variants may include several valves each formed by a coil placed in front of or behind the opening and by a single movable closing part constituted by the disc with an axially magnetized core, described above.

 The moving part moving inside the holding cage will be attracted and pressed against the opening corresponding to the ordered coil. Conversely, it will return to its low rest position as soon as the magnetic field of attraction is canceled.

 The rest position is the lowest position in which the closing part can be in the grid holding cage under the effect of its weight.

 Of course, the shape of the lower part of the body of the fluidic member will be adapted to the different specific requirements of the intended application.

 Thus, a conformation avoiding the flat fall of the closure piece is preferable.

 This function is mainly fulfilled by the mesh retaining cage.

 In order to fully understand the advantage and superior performance of the invention in the medical field, that is to say in its application to the measurement of the resistance of the respiratory tract, we will analyze below, in a comparative manner , the pressure variation curves at the buccal level, with reference to FIGS. 8 and 9.

 These curves show in a particularly clear manner the differences in efficiency and performance between a conventional valve (poorly damped) used for this purpose, and the ultra-fast shutter device according to the invention.

 These are curves representing the oral pressure "P" as a function of time "t" from an origin "to".

Different characteristic times on the time scale are particularized as follows tl = control to close the valve t2 = total closure of the valve with the device
according to the invention (point F) t3 = end of the pressure rise with the device
according to the invention, that is to say balance of
pressures (point M) t4 = pressure balance with a device
classic poorly damped (point P) t5 = valve opening (point O) t6 = cancellation of overpressure due to occlusion
(point A).

We determine the following segments
FM: rise and balance of the alveolus pressure
buccal
MO: pseudo-level corresponding to a slight rise
in pressure due to the continued movement of
ribcage
OA: pressure drop following opening.

 For the same starting point corresponding to the command to close the valve and the same delay due to the control circuit, there are two distinctly different forms of curves in their first FM part.

 The curve representing the rise in pressure is perfectly straight and sharply inclined in the case of the ultra-rapid and immediately leaktight shutter device according to the invention, while in the case of a conventional valve which is poorly damped, the rise in pressure is slower and jerky and imprecisely and hesitantly connected to the pseudo-level.

 It is thus possible to start the measurement as soon as the pressure equilibration is made, that is to say from point M in the case of the ultra-fast and immediately waterproof device according to the invention, while the entire hatched area is completely unusable in the case of a poorly damped conventional valve. For the latter, the pressure equilibrates only at point P, that is to say with a certain delay, shifting the point of exploitation of the measurement accordingly. Indeed, the exploitation of the curve only becomes possible after complete amortization which requires at least 20 milliseconds.

 This is explained because the twists cause leaks and therefore pressure disturbances. Not only does the equilibrium pressure remain disturbed as before, but in addition, the equilibration time is longer. Thus, the entire hatched area is entirely lost.

 The gain in pressure measurement proves to be notably interesting, it makes it possible to reduce the total duration of occlusion and to make the measurements more significant.

 It makes it possible to further decrease the total duration of the occlusion due to the quality of the curve and the consecutive possibilities of extrapolation.

 These advantages can be transposed in the aeraulic and fluidic fields at low and medium pressure of use or service.

 The invention has been described above in detail. It is understood, however, that various simple modifications, additions, direct variants, substitutions by equivalent means fall within the scope of this protection.

Claims (9)

 1. Ultra-fast shutter device for gaseous fluids in particular for medical use, characterized in that it consists of a valve (11) enclosed in a central chamber (2), valve (11) consisting of a coil (19) disposed around or in front of at least one orifice and a movable magnetic closing element repelled at rest and attracted to closing by the magnetic force of the magnetic field developed by the coil (19), said coil being controlled at rest by a current generating a repulsive field and in operation by a strong contrary current developing a powerful magnetic field of attraction, consecutive to the discharge of a capacitor C through the electrical circuit of the coil and in that the closing part closes the orifice through an O-ring (18).  2. Device according to claim 1, characterized in that the closing element comprises a core magnetized axially by a magnet (15).  3. Device according to claims 1 and 2, characterized in that the closing element comprises a guide rod (13) supported by a mechanical assembly.  4. Device according to claims 1, 2 and 3, characterized in that the capacitor C is charged by a continuous high-voltage source SC, discharged on the coil (19) by a discharge relay RDD, said relay being controlled by an external locking circuit CV in the working position for discharging the capacitor C and in the rest position to close, on the coil (19), a direct current source of reverse polarity SR generating, in the coil, a continuous field repulsion now resting the valve closure part (11) away from the coil.  5. Device according to claims 1, 2 and 4, characterized in that the central chamber (2) has two inlet ports each comprising an electromagnetic coil, a transverse outlet port and a double valve formed by two closing parts to magnetic core, opposite each inlet, the two closure parts being mechanically coupled by a rod supported by a carrier assembly, leaving a passage recess to the right of the outlet.  6. Device according to claim 5, characterized in that the closure part is free in a holding cage in front of the orifice to be closed around which the coil is disposed.  7. Device according to claim 6, characterized in that it has several inlet or outlet channels, each orifice of which has a coil controlled by an assembly, a closure element with a magnetic core moving freely in an adjoining holding cage at the ports of the entry or exit channels is common to all ports.  8. Device according to claim 5, characterized in that it comprises three channels including two air channels (22, 23) selectively closed and an outlet channel (24), a body (25) with central chamber (26) open to its two ends and having a transverse median conduit (27) which opens into the central chamber (26) through an orifice (29) in line with a guide support (30) on which is slidably mounted a movable assembly (31) forming a double valve constituted by two shutter elements mechanically paired in the form of discs (32) and (33) with a magnetic core, axially joined by a guide rod (38).  9. Alveolobuccal pressure and flow sensor according to the preceding claims taken as a whole, characterized in that it comprises the ultra-fast obturation device claimed above, provided with a pressure tap (20) in the buccal duct , communicating with a pressure sensor CP located in the handle, shutter device followed by a flow measurement unit (8) comprising a flow sensor.