Analytical apparatus and method measuring the concentration of target gas contained in a gas sample, and apparatus and method for verifying said analytical apparatus

Abstract

Analytical apparatus and method measuring the concentration of a target gas contained in a gas sample, and apparatus and method for verifying said analytical apparatus The invention relates to an analytical apparatus (100), having: a valve which releases a fluid guide unit between a measuring chamber and the surrounding space, when it occupies an extreme release location, and closes this guide unit when it occupies an extreme closure location; a gas sensor (50) which measures the concentration of a target gas contained in a gas sample contained in said measuring chamber, in which apparatus said valve remains permanently at the extreme closure location during a verification phase during which a pressure sensor (12.1, 12.2) repeatedly measures the difference between the ambient pressure and the pressure prevailing in said chamber and the valve ensures closure with effective fluid tightness if the difference between the two pressures is sufficiently large during said verification phase and if said difference is significantly smaller at the end of said phase, said valve shows a sealing defect. Figure to be published with the abstract: Fig. 4.

Description

Title of the invention: Analytical apparatus and method measuring the concentration of target gas contained in a gas sample, and apparatus and method for verifying said analytical apparatus

[0001] The present invention relates to an analysis apparatus which is capable of measuring the concentration or quantity of a target gas contained in a gas sample, and is capable of automatically checking its own tightness. The invention further relates to a verification apparatus and a verification method for said analysis apparatus, as well as an analysis method using the latter.

[0002] Analysis devices equipped with electrochemical sensors are known. An analysis device according to the invention may also comprise a sensor of this type. The reliability of such an analysis device is decisively dependent on the actual state of the electrochemical sensor.

[0003] An analysis apparatus according to the invention may also include a gas sensor of another type, for example a photo-optical, photo-acoustic or oxidation-causing (catalytic) sensor, also referred to as a "reaction heat sensor".

[0004] A possible use of the analysis apparatus according to the invention lies in the examination of a person being tested, with a view to detecting a substance likely to be found in his body and the presence of which can be attested in a breath sample of said person, which substance is in particular alcohol.

[0005] The object of the invention is to provide an analysis apparatus, a verification apparatus, a verification method and an analysis method which are capable of measuring the concentration or quantity of a target gas contained by a gas sample, and offer reliability superior to that of known analysis apparatuses, verification apparatuses, verification methods and analysis methods.

[0006] The analysis apparatus according to the invention comprises a measuring chamber and a gas sensor, said chamber being capable of receiving a gas sample to be examined, for example a portion of a breath sample of a person being tested. Said sensor is capable of measuring the concentration and / or quantity of a pre-established target gas contained by the gas sample when the latter is in the measuring chamber. The same structural element may include said sensor and provide said chamber. It is possible for said sensor to be capable of measuring the respective concentration or quantity of several pre-established target gases, contained by the same gas sample contained in the measuring chamber, or even the sum of the concentrations or quantities of target gases. Of course, it is also possible that the target gas is not contained, by the gas sample, in a concentration exceeding a detection threshold.

[0007] It will be noted that the formulation, according to which a sensor is capable of measuring a physical quantity, means that said sensor is capable of directly measuring said physical quantity or a quantity detected in correlation with the quantity to be measured, that is to say an estimated criterion of said quantity to be measured. In the case where the physical quantity is the concentration or the quantity of a target gas, the correlated quantity is presented, for example, as the electrical voltage applied to an electrically conductive structural element, or as the intensity or the electrical power of the current flowing in said element or as the electrical charge, or even as the electrical resistance or the temperature of said element traversed by the current. The measurement carried out delivers a value of said physical quantity to be measured.

[0008] In a practical application of the invention, the gaseous sample is derived from a breath sample provided by a test subject, and the target gas is exhaled alcohol or any other component contained, or capable of being contained, by a breath sample. It is then appropriate to investigate, with said test subject, whether or not alcohol is present in his or her bloodstream. If so, it is well known that a breath sample generally contains exhaled alcohol. The gaseous sample may also emanate from a region to be monitored. The target gas may also, for example, be a target gas that is combustible, toxic, or otherwise harmful to humans, or even oxygen, a narcotic, or carbon dioxide.

[0009] A fluid guiding unit equipping the analysis apparatus is capable of establishing fluid communication between the measuring chamber and a space surrounding said apparatus. The expression "fluid guiding unit" must be understood as designating a structural element which is capable of channeling a fluid along a trajectory pre-established by the structural organization and arrangement of said element and which, ideally, prevents said fluid from leaving this trajectory. The meaning "fluid guiding unit" includes in particular a tube, a smooth flexible pipe and a pleated flexible pipe.

[0010] A valve of the analysis apparatus can be brought to an extreme release location, to an intermediate closure location and to an extreme closure location. Said intermediate closure location is distinguished from said extreme closure location. During a transfer (movement) from one of the extreme locations to the other extreme location, the valve reaches the intermediate closure location. When said valve occupies the extreme release location or a location between said extreme release location and the intermediate closure location, this allows a gaseous sample to flow into the measuring chamber from the surrounding space, passing through the fluid guide unit, which may result, in particular, from the fact that said sample is sucked into said chamber and / or diffuses into the latter, passing through said guide unit.

[0011] The fluid guide unit is closed when the valve is located at a closing location, so that, ideally, no fluid communication is established between the measuring chamber and the surrounding space, but said chamber is separated from said space by means of complete fluid tightness. The term "closing location" is understood to mean the intermediate closing location, the extreme closing location or a location located between said intermediate and extreme locations. In other words, the valve closes the fluid guide unit when it occupies a location falling within a range of closing locations, which range includes the region located between the intermediate closing location and the extreme closing location. The statement "ideally" refers to the ideal case in which said valve closes without failure, and thus with fluid tightness.The characteristic, according to which the intermediate closure location is distinguished from the extreme closure location, arises in particular from the fact that at least one constituent element of said valve is elastically deformable in general.

[0012] As a general rule, the valve allows the gas sample to flow through the fluid guide unit, from one side to the other, also when said valve occupies a location which is neither the extreme release location nor a closure location, but a location between the intermediate closure location and said extreme release location. Frequently, however, the volume flow rate is less than that existing when said valve occupies the released extreme location.

[0013] As long as fluid communication is permitted, the pressure in the measuring chamber generally equilibrates with the ambient pressure. On the other hand, as long as said chamber is separated from the surrounding space in a completely fluid-tight manner, a difference may appear permanently between said pressure in the chamber and said ambient pressure, assuming that said valve actually breaks said fluid communication, with fluid tightness.

[0014] A pressure detection assembly of the analysis apparatus comprises at least one pressure sensor and is capable of measuring a pressure difference, this being the difference between the pressure prevailing in the measuring chamber and the pressure prevailing in the space surrounding said analysis apparatus. It is naturally possible for said detection assembly to measure, at least from time to time, a zero pressure difference. The or each sensor measures the pressure at a respective measuring location. Said location, or a measuring location of this sensor assembly, is located, for example, on or in the measuring chamber, or on or in the fluid guide unit, more precisely between the valve and said chamber, or on or in an optional additional fluid guide unit which connects said chamber to an optional suction unit.

[0015] A control device (control unit) of the analysis device, processing signals, is capable of automatically deciding whether or not the valve actually closes the fluid-guiding unit with fluid tightness, when said valve occupies the extreme closing location. The control device constitutes a part of the verification device according to the invention. For this decision, said control device ensures that the valve occupies said extreme closing location, continuously, during a verification phase having at least a pre-established minimum duration, the duration of said phase being able to exceed said minimum duration. The control device has ensured that, prior to said verification phase, the valve has been transferred to the extreme closing location from the intermediate closing location, or from any other location.During this verification phase, of course, no gaseous sample, fluid or particle of any other nature can enter the measuring chamber from the surrounding space, assuming that said valve effectively closes the fluid guide unit in a fluid-tight manner. Furthermore, the control device ensures that the pressure sensor assembly measures the differential pressure several times, i.e. at least twice, during the verification phase, for example with a fixed scanning frequency.It is possible to envisage a structural arrangement, configuration or equipment in which the gas sensor measures the concentration or quantity of target gas, in the measuring chamber, during the verification phase in which the valve continuously occupies the extreme closure location, or during a measurement phase overlapping or encompassing said verification phase.

[0016] The control device then decides, at a minimum, that the valve effectively closes the fluid guide unit, with fluid tightness, when it has detected the situation in which, during the entirety of the verification phase, i.e. at each exploration instant included in said phase, the measured pressure differs, in the measuring chamber, by at least a pre-established minimum deviation from the ambient pressure, more precisely upwards or downwards depending on the structural organization, configuration or arrangement of the device analysis. Thus, when the valve closes the fluid guide unit in a fluid-tight manner, the pressure prevailing in said chamber may be higher or lower than said ambient pressure during the entirety of said verification phase.

[0017] The control device then decides, at a minimum, that the valve does not seal the fluid guide unit with sufficient fluid tightness when it has detected the situation in which, at least at the completion of the verification phase, the pressure prevailing in the measuring chamber differs, with respect to the ambient pressure, at most by a pre-established fraction of the minimum deviation which is firmly recorded by a number greater than or equal to 0 and less than 1. Said fraction is preferably less than or equal to 0.5, less than or equal to 0.25 with particular preference, that is to say it represents half or a quarter, for example.

[0018] In the case where the control device has detected neither one nor the other result, a state of the valve cannot be detected with certainty. In one structural arrangement, said control device automatically causes, at a subsequent stage, that the check just described is carried out again, for example with a longer verification phase. In another structural arrangement, said control device causes the output of a corresponding message, in this situation, which message can prompt a user to check the analysis device.

[0019] According to the invention, a preferred verification method, devoted to the automatic control of an analysis apparatus comprising a measuring chamber, a fluid guide unit located between said chamber and the surrounding space, a valve assigned to said guide unit, and a gas sensor, includes the steps executed automatically, consisting - in that it is ensured that the valve occupies the extreme closure location continuously, during the verification phase, - in that the difference between the pressure prevailing in the measuring chamber and the pressure prevailing in the surrounding space is measured repeatedly during said verification phase, and - in that it is automatically decided whether or not said valve occupying said extreme closure location actually causes, in a fluid-tight manner, a closure of the fluid guide unit.

[0020] It is then decided, at a minimum, that the valve actually causes a fluid-tight closure when, during the entire verification phase, the measured pressure prevailing in the measuring chamber differs, at a minimum, from the pre-established minimum deviation from the ambient pressure.

[0021] It is then decided, at a minimum, that the valve does not cause any fluid-tight closure when, at the end of the verification phase, the pressure prevailing in the measuring chamber differs, with respect to the ambient pressure, at most by the pre-established fraction of the minimum difference.

[0022] A verification apparatus according to the invention has the effect of ensuring the execution of the steps which have just been described.

[0023] As already explained, the process of moving the valve away from the extreme release location results in said valve reaching the intermediate closure location first and then the extreme closure location. In the presence of a malfunctioning valve, the fluid guide unit is closed in a fluid-tight manner at each closure location of said valve. Because said intermediate closure location differs from said extreme closure location, the volume of a space within the analysis apparatus also varies, which space is available for a gas sample, and comprises the measuring chamber and the segment of said guide unit which is interposed between the valve and said chamber.In the case where said valve actually closes the fluid guide unit at each closing location, with fluid tightness, the quantity of the gas sample does not vary in this space. The movement of said valve therefore governs a difference between the ambient pressure and the pressure prevailing in said space, this pressure difference being determined and evaluated.

[0024] When the valve does not seal the fluid guide unit in a fluid-tight manner, undesirable situations may arise in which chemical substances of the gas sensor, designed as an electrochemical sensor, may vaporize. Harmful substances emanating from the surrounding space may, by flowing through said guide unit, reach the measuring chamber and damage the gas sensor therein. Water vapor may enter said chamber and water may condense on a wall thereof. This is undesirable, in particular, when said sensor includes a radiation source and a detector, and when at least one wall of said chamber reflects the radiation in order to extend the optical path. Water may also condense on a window of the measuring chamber, this window then being traversed by electromagnetic radiation.

[0025] In order for a gas sample to flow into the measuring chamber from the surrounding space, passing through the fluid guide unit from one side to the other, the valve must necessarily be driven by a movement causing it to leave a closure location. To ensure that the aforementioned undesirable situations occur as rarely as possible, it would be appropriate for said valve closes said guide unit with effective fluid tightness, unless a gas sample flows into the measuring chamber by traveling right through said guide unit, or unless said chamber is rinsed by traveling right through said guide unit, to be able to receive a new gas sample in the sequence.

[0026] The situation may arise in which, even when occupying the extreme closure location, the valve does not close the fluid guide unit in a completely fluid-tight manner, which may, for example, be caused by material fatigue or by a failure affecting an adjustment drive imparting movements to a constituent element of the valve, or even by the stubborn deposition of at least one particle between a moving part and a fixed part of said valve. The reasons why this situation is undesirable have been explained above.

[0027] As already explained, the gas sensor can be damaged, over time, when the valve does not close the fluid guide unit in a completely fluid-tight manner, also when it occupies the extreme closing location. Therefore, it is imperative to detect this untimely occurrence. The invention indicates a way to automatically check (test) whether the valve, occupying the extreme closing location, actually closes said guide unit in a completely fluid-tight manner. This check does not require any action on the part of a user. Moreover, the control device is able to automatically trigger the steps required for the check, and to automatically carry out the required evaluation. Therefore, the analysis device is able to self-test in automatic mode.This check can be carried out repeatedly, for example each time the analysis device is switched on or when a pre-established period of time has expired since the last check, or after N gas samples have flowed into the measuring chamber, N >= 1 then being a pre-established number, or even when the gas sensor has detected, overall, a pre-established quantity of the target gas since the last check.

[0028] The possibility is provided for a user to additionally be able to manually trigger the steps required for the control. For example, said user activates a corresponding actuating element of the analysis device.

[0029] The control device, which is part of the verification device and triggers the steps targeting the control of the analysis device, receives and processes a signal from the pressure detection assembly. Said control device may be an integral part of said analysis device. It is also possible to install said control device spatially at a distance from a housing of the analysis device and to integrate, in said housing, the measuring chamber, the gas sensor, the guide unit of fluids, the pressure sensing assembly, and an optional drive. In this structural arrangement, a data connection, preferably a wireless data connection, is established, at least from time to time, between said sensing assembly and said remotely located spatially located control apparatus.

[0030] In the event that the control device has detected that the valve does not close the fluid guide unit in a fluid-tight manner, said control device preferably causes at least one transmitter unit to deliver a corresponding message, at least in a form perceptible to a human. Said unit, or a transmitter unit, may be an integral part of the analysis device. It is also possible to install said unit, or a transmitter unit, spatially remote from said analysis device.

[0031] The valve generally comprises a part movable with respect to the fluid guide unit and a part fixed with respect to said guide unit, namely a movable obturator body (obturator part) and a fixed obturator seat. Said body is applied against said seat at each obturator location of the valve. During the process by which said valve is transferred to the extreme obturator location from a release location, the effect typically occurs that the obturator body reaches the obturator seat, in a first step, after which the intermediate obturator location is reached. Since the obturator seat is generally elastic and the obturator body, and / or other constituent elements of the analysis apparatus, may be similarly endowed with elasticity, said body continues its movement after it has already reached said seat.This results in a variation in the volume of a space including the measuring chamber and the segment of the fluid guide unit which is located between said chamber and said seat. In the presence of a valve operating without failure, i.e. ensuring a fluid-tight closure, this space is no longer in fluid communication with the surrounding space as soon as the closure body has reached the closure seat, i.e. after the intermediate closure location has been reached, and before the extreme closure location is reached. The pressure varies accordingly in the space just mentioned, after said body has reached said seat, while the ambient pressure practically does not vary during the verification phase. The precisely described effect therefore governs a variation in the pressure difference between the pressure prevailing in said space and the pressure prevailing in the surrounding space.

[0032] According to the invention, the control device ensures, during a check, that the valve maintains the extreme closure location during the check phase having the pre-established minimum duration. In the case where said valve then actually closes the fluid guide unit in a manner fluid-tight, this pressure difference persists throughout the entire verification phase. Expressed in more precise terms, the value of said pressure difference is greater than or equal to the minimum deviation during the entirety of said phase, and therefore at each moment of exploration during the latter. If, conversely, during the verification phase, the pressure prevailing in this space approaches the ambient pressure from the top or from the bottom, although the valve is located at said extreme closure location, said valve does not close said guide unit in a sufficiently fluid-tight manner.

[0033] In many cases, the invention does not require that an existing analysis apparatus be supplemented by a sensor or by a part of any other nature. Frequently, in fact, the presence of a sensor measuring the pressure in the measuring chamber is already noted. A signal from this pressure sensor is used, for example, to measure the volume flow entering said chamber, and / or leaving it. In many instances, this already present sensor measures the pressure difference relative to the ambient pressure.

[0034] In the case where the analysis apparatus is used to receive a breath sample from a test person, the signal from the pressure sensing assembly is also used, for example, to measure the volume flow rate during the delivery of said sample and to deduce therefrom the volume flow rate of the breath sample delivered so far, and / or to detect the event during which the test person has stopped delivering said sample. This makes it possible to determine whether or not a test person has actually introduced a breath sample of sufficient size.

[0035] This already existing pressure sensor can, in many cases, be additionally used for the invention, which can be concretely applied, in many instances, to an existing analysis device since a corresponding software is operated, on the control device, without any additional modification being necessary. It is not common, in particular, that a sensor has to be supplemented.

[0036] The control device preferably ensures that an alarm is emitted, in a form perceptible to a human being, upon detection of the undesirable event consisting in that the valve, occupying the extreme closing location, does not close the fluid guide unit in a fluid-tight manner. This alarm is preferably emitted on a transmitter unit of the analysis device.

[0037] During the verification phase in which the valve is ensured to be at the extreme closure location, the analysis device cannot be used to analyze a gas sample. The control device preferably ensures that a corresponding message is delivered during this verification phase, namely a message indicating that the said analysis device cannot in fact receive any gas samples. This has the effect of reducing the risk that, during the said verification phase, a user may propose to use the analysis device, and / or may wrongly consider the said device to be defective.

[0038] According to the invention, the control apparatus ensures that a sequence of steps is executed at least once, this sequence making it possible to automatically check whether the valve occupying the extreme closure location actually closes the fluid guide unit in a fluid-tight manner or not. This sequence is executed repeatedly, preferably, for example regularly with a pre-established scanning frequency, or when a pre-established period of time has elapsed since the last check. In a structural arrangement, said sequence is always executed at the time when the analysis apparatus is switched on and first performs a self-test, after switching on, or it is executed after said apparatus has examined N gas samples, N >= 1 being a pre-established number, preferably N >= 10.It is also possible that this sequence is executed in response to the detection of a matching entry made by a user.

[0039] The valve is preferably provided with a closure body and a closure seat, said body being movable relative to said seat. The valve occupies a closure location when the body is in contact with the seat. At least when said body then has the maximum possible distance from said seat, said valve occupies the extreme release location. It occupies the extreme closure location when said body is at the maximum possible distance from the location of said extreme release location.

[0040] In a first concrete form of arrangement, the closure seat is interposed between the closure body and the measuring chamber, in which first form a movement of said body towards said chamber, relative to said seat, has the effect of transferring (moving) the valve to the extreme closure location. In a second concrete form of arrangement, conversely, the closure body is interposed between the closure seat and the measuring chamber, in which second form a movement away from said chamber, relative to said seat, has the effect of transferring said valve to said extreme closure location. In both concrete forms of arrangement, a movement of said body in the respectively opposite direction has the effect of transferring said valve to the extreme release location.

[0041] It is possible for the gaseous sample to diffuse into the measuring chamber. In the case where said gaseous sample comes from a breath sample having been provided by a person being tested, it may happen that the kinetic energy developed by said person when delivering said breath sample is sufficient to pass (convey) the gaseous sample into the measuring chamber. In a preferred structural arrangement, on the other hand, the analysis device is provided with a fluid conveying unit which comprises, for example, a cylinder and a pump or a blower, or even a variable volume chamber, a bellows in particular, as well as a regulating drive or a motor, or a drive of any other type. The conveying unit is capable of sucking a gaseous sample into the measuring chamber, with a path right through the fluid guiding unit.Conversely, said routing unit is capable of rinsing said measuring chamber, preferably with ambient air, and for example ensures that the gas contained in said chamber is replaced by ambient air.

[0042] In a possible structural arrangement, the analysis apparatus is equipped with an adjustment drive in addition to the fluid conveying unit. The latter is mechanically connected to said conveying unit and to a movable part of the valve. The adjustment drive is capable of selectively transferring said valve to the extreme release location or to the extreme closure location, since said drive imparts movements to the closure body relative to the closure seat. Unlike a motor, an adjustment drive is capable of moving only along a limited region and of oscillating within it.

[0043] In one structural arrangement, an adjustment drive of the fluid conveying unit is connected to a movable part of the valve. It is also possible to envisage the presence of an adjustment drive assigned to said valve, but to provide no conveying unit. In this structural arrangement also, said drive transfers said valve from one of the locations to the other location.

[0044] In a concrete form of arrangement, the fluid conveying unit is mechanically coupled to the valve. During the aspiration of a gas sample, said conveying unit brings said valve to the extreme release location and conversely brings the latter to the extreme closure location during rinsing. This structural arrangement saves the need for a separate adjustment drive for said valve. It is also possible for said conveying unit to transfer said valve to said extreme closure location during aspiration and then back to said extreme release location during rinsing.

[0045] The foregoing developments have described a preferred structural arrangement in which a fluid delivery unit is capable of aspirating a sample gaseous in the measuring chamber with a path, through and through, of the fluid guide unit, and is simultaneously capable of transferring the valve from one of the extreme locations to the other extreme location. In a concrete form of arrangement, the conveying unit ensures that the valve is brought to the extreme release location even while the gaseous sample is being sucked in. In a variant of a concrete form of arrangement, conversely, said conveying unit ensures that said valve is transferred to the extreme closure location during the suction of said sample.

[0046] In a structural arrangement, the fluid conveying unit includes a suction chamber unit and an adjustment drive, which suction chamber unit provides a chamber with a variable volume. Said unit is provided, for example, with a piston capable of oscillating in a cylinder, or with a bellows. Said provided chamber is in fluid communication with the measuring chamber. The adjustment drive is mechanically connected to the suction chamber unit and is capable of both increasing and decreasing the volume of said provided chamber. An increase in the latter involves the suction of a gaseous sample into said measuring chamber. A decrease in said volume governs a flushing thereof.

[0047] This structural arrangement results, in many cases, in a relatively compact analysis apparatus. It is sufficient that the adjustment drive is able to perform a linear movement in two mutually opposite directions, over a relatively short distance. As a rule, the volume of the chamber still varies after the valve has reached the intermediate closing location. In many cases, when the valve is transferred from the intermediate closing location to the extreme closing location, the effect caused by the variation of said chamber volume is superimposed on the effect caused by a movement of said valve. As a rule, said variation in volume exerts a more accentuated effect than that of said movement. In this case too, the pressure difference makes it possible to indicate whether the valve occupying said extreme closing location closes, or not, the fluid guide unit with fluid tightness.

[0048] The structural arrangement provided with the suction chamber unit can be combined with the structural arrangement in which the valve comprises a closure seat and a closure body movable relative to said seat.

[0049] In a concrete arrangement form, the adjustment drive comprises two constituent elements: - a return element preferably comprising at least one mechanical or pneumatic spring, and - an electric drive, an electromagnet for example.

[0050] The electric drive tends to vary the volume of the chamber provided and to impart movements to the shutter body, more precisely in opposition to the restoring force of the restoring element. In the deactivated state of said drive, said element modifies the volume of said chamber and moves said body. The restoring torque tends, preferably, to transfer the valve to the extreme closing location and to maintain it there.

[0051] After the gas sensor has analyzed the gas sample, it is generally imperative to rinse the measuring chamber in order to examine another gas sample at a subsequent stage. Rinsing reduces the danger that the old sample will falsify a measurement result targeting the new sample. In a preferred form of concrete arrangement, the measuring chamber is rinsed by means of a path, right through, of the fluid guide unit. This form eliminates the need to specifically provide an additional guide unit for rinsing said chamber. In the step involving rinsing of the measuring chamber, the fluid guide unit preferably brings the valve to the extreme closing location or, alternatively, to the extreme release location. This form of concrete arrangement also eliminates the need to provide an additional adjustment drive allocated to the valve.

[0052] According to the invention, the gas sensor of the analysis device is capable of measuring the concentration of a target gas contained in a gas sample even while the latter is in the measuring chamber. Different structural arrangements of this sensor are possible.

[0053] In a structural arrangement, the gas sensor is an electrochemical sensor. Such a sensor comprises a measuring electrode, a complementary electrode, an ionically conductive electrolyte interposed between these two electrodes and, additionally, an optional reference electrode. The target gas causes an electrochemical reaction inducing a flow of current from one to the other of said electrodes, which reaction depends on the target gas concentration and influences a detected quantity of the gas sensor, preferably an electrical detected quantity, in particular the electrical charge. A detected quantity sensor is capable of measuring said detected quantity, the latter being in correlation with the desired target gas concentration. In many cases, an analysis device equipped with an electrochemical sensor consumes less electrical energy than an analysis device having a sensor of a different type.

[0054] In another structural arrangement, the gas sensor is an optoelectric (photoelectric) sensor. A radiation source induces, in the measuring chamber, electromagnetic radiation which travels through said chamber and impacts on a photodetector, which generates an electrical signal dependent on the intensity said incident electromagnetic radiation. Typically, a target gas to be detected absorbs part of the electromagnetic radiation in a wavelength range dependent on said target gas, so that the electrical signal of the photodetector is correlated with the concentration of target gas. Instead of electromagnetic radiation, the aforementioned source can also emit sounds.

[0055] The gas sensor can also be designed as a photoacoustic sensor. Modulated electromagnetic radiation is emitted, which travels through the measuring chamber in which the target gas absorbs a portion of said radiation. The absorption causes a localized variation in temperature, which modulates according to the emitted radiation. Said caused variation induces an acoustic effect in a reference chamber, which induced effect is measured by an acoustic sensor and is correlated with the desired target gas concentration.

[0056] In a structural arrangement, the gas measuring device has two gas sensors, preferably two sensors of different types, in particular an electrochemical sensor and an optoelectric sensor. In a concrete arrangement, the two sensors are arranged in parallel and a gas sample reaches both parallel sensors each time. The two gas samples emanate, for example, from the same breath sample of a person being tested. In another concrete arrangement, the two sensors are connected in series and the same gas sample reaches both sensors one after the other. The structural arrangement with two sensors increases reliability and allows a plausibility check in which the two signals from the two sensors are compared with each other. In many cases, moreover, it is possible to use two sensors with different scanning frequencies.In many cases, moreover, the analysis device can also continue to be used when one of the two sensors has proven to be faulty.

[0057] In a structural arrangement, the analysis apparatus includes an introduction unit, in particular a nozzle. Said introduction unit can preferably be releasably connected to a base body of said apparatus and is capable of receiving a breath sample from a test subject introducing this sample into said unit, which is in fluid communication with the fluid guide unit. As a gaseous sample flowing into the measuring chamber, the analysis apparatus uses a part of a breath sample that a test subject has introduced into the introduction unit and which is received by the latter, or the entirety of said breath sample. This part of the sample flows into said measuring chamber by passing through said introduction unit and running right through said fluid guide unit.Typically, the remaining portion of the sample returns to the surrounding space by circulating past the measuring chamber. In this structural arrangement, the gas, or a target gas, preferably occurs as expired alcohol.

[0058] According to the invention, the pressure detection assembly is configured or structurally arranged to repeatedly measure, during the verification phase, the difference between the ambient pressure and the pressure prevailing in the measuring chamber. In the structural or constructive arrangement described below, it is sufficient for said detection assembly to comprise a pressure sensor capable of measuring the pressure at a measuring location, which is located at one of the following locations: - in, or on the fluid guide unit, between the measuring chamber and the space surrounding the analysis device, more precisely at a location between the valve and said chamber, namely downstream of said valve; - in, or on said measuring chamber; - in, or on an additional and optional fluid guidance unit, the latter connecting said chamber to an optional suction unit.

[0059] The control device ensures that the pressure measurement by the pressure sensor at the measuring location is carried out as follows: - on the one hand, said sensor repeatedly measures the pressure during the verification phase during which the valve occupies the extreme closure location; - on the other hand, said sensor measures the pressure at least once, preferably several times when said valve occupies a release location, in particular the extreme release location.

[0060] The term "release location" is understood to mean the extreme release location or a location between said extreme release location and the intermediate closure location. At a release location, the valve is fully or at least partially open and the fluid guide unit is at least partially released.

[0061] When the valve occupies a release location, fluid communication is established between the surrounding space and the measuring chamber and, as a result, the pressure prevailing at the measuring location approximately coincides with the pressure prevailing in said surrounding space. The accepted assumption, according to which the pressure does not vary appreciably in the surrounding space, at the stage at which the valve is transferred from one to the other of the extreme locations, is ordinarily justified.

[0062] The control device determines the ambient pressure as a function of at least one pressure having been measured, at the measuring location, when the valve occupied a release location. In one concrete arrangement, said apparatus uses the pressure prevailing at said measuring location as ambient pressure, knowing that the pressure sensor measured this pressure when said valve occupied a release location. In another concrete arrangement, said control apparatus establishes an average of several pressures having been measured, at said measuring location, when said valve occupied different release locations.

[0063] This structural arrangement requires only a single pressure sensor. Such a pressure sensor is frequently already present.

[0064] In a concrete form of arrangement, the analysis device is provided with its own voltage supply unit and can thus be used as a mobile device. It is also possible to connect said device to a fixed voltage supply network. These two concrete forms of arrangement can be combined with each other.

[0065] In a structural arrangement, the analysis apparatus is equipped with its own output unit on which said apparatus is able to deliver information, in particular at least one, preferably all of the following information: - the measured concentration or quantity of, or at least one of, preferably each target gas contained in the gas sample; - whether the said measured concentration or quantity is within or outside a pre-established range of values; - the question of whether or not the analysis device accurately performs the self-test in accordance with the invention and is, consequently, factually not capable of receiving a new gas sample; - whether an own voltage supply unit of said measuring device is still capable of providing sufficient electrical energy; and - whether or not the valve occupying the extreme sealing location actually seals the fluid guide unit in a fluid-tight manner.

[0066] In a structural arrangement, the analysis apparatus includes a communication unit by means of which a data connection can be established, at least from time to time, between said apparatus and a spatially remote receiver. Via this connection, the analysis apparatus is capable of transmitting a measurement result to said receiver. In a structural arrangement, said apparatus is further capable of transmitting to said receiver the result stating that the valve, occupying the extreme closure location, no longer closes fluid-tight.

[0067] The invention is described below with the support of an exemplary embodiment illustrated in the attached drawings, in which:

[0068] [Fig-1] is a perspective representation observed from the side of the analysis apparatus of the exemplary embodiment, with omission of the casing and the adjustment drive;

[0069] [Fig.2] is a cross-section observed from the side of the analysis apparatus of the [Fig.l];

[0070] [Fig.3] is a fragmentary illustration showing a detail of [Fig.2];

[0071] [Fig.4] is a top view of the analysis apparatus of the exemplary embodiment, with omission of a crankcase cover;

[0072] [Fig.5] represents an example of the temporal evolution of the pressure difference at the fully functional state of the valve; and

[0073] [Fig.6] is a schematic representation of the temporal evolution of the difference pressure, respectively in the fully functional state and in the defective state (not tight) of said valve.

[0074] [Fig.l] is a schematic illustration of an analysis apparatus 100 according to the exemplary embodiment, capable of measuring the exhaled alcohol content in a breath sample. The exhaled alcohol content, in a breath sample having been provided by a person tested, is known to correlate with the blood alcohol level of said person.

[0075] The person being tested introduces a breath sample A into a funnel-shaped mouthpiece 30 shown schematically. A portion of said sample A serves as a gas sample Gp, which passes through an inlet part 1, travels through a fluid guide unit described in more detail below, and then reaches a measuring chamber 3 (Figures 2 and 3) which, in the exemplary embodiment, has rotational symmetry with respect to a median axis MA. Preferably, the remaining portion of said sample A returns to the surrounding space without reaching said chamber.

[0076] [Fig.l] does not show a casing 9 (figures 3 and 4) of the analysis device 100, the latter including a measuring chamber of which only a covering plate 17 and the median axis MA are illustrated in this [Fig.l], as well as an electrochemical sensor 50 known from the state of the art. Said sensor 50 is capable of analyzing the exhaled alcohol contained by the gaseous sample Gp located in the measuring chamber, and operates according to the principle of a fuel cell whose fuel consists of alcohol.

[0077] The sensor 50 is configured or structurally organized as follows: the electrical contact of a measuring electrode 21 is established by a contact wire 34, the electrical contact of a complementary electrode 20 being established by a contact wire 33. in contact. An electrolyte provided with an ionic conduction agent is interposed between the two electrodes 20 and 21, said agent being, for example, sulfuric acid or phosphoric acid, or even perchloric acid, with dilution in water. Ions may be in motion in the electrolyte, which creates an ionically conductive bond between said measuring electrode 21 and said complementary electrode 20, but electrically insulates the two electrodes 20 and 21 from each other. Both said electrodes 20 and 21, and the two contact wires 33 and 34, consist of a material not chemically attacked by the electrolyte, platinum or gold for example.

[0078] As already explained, the electrochemical sensor 50 operates according to the principle of a fuel cell. A gaseous sample Gp arrives in the measuring chamber 3 equipped with the covering plate 17. Said sensor 50 oxidizes the exhaled alcohol contained by the sample Gp and, in the ideal case, all of the exhaled alcohol contained by said sample Gp. The chemical reaction, occurring during the oxidation, results in the circulation of an electric current between the measuring electrode 21 and the complementary electrode 20. A sensor of detected quantities, not illustrated, measures the electric charge, that is to say the total quantity of the electric current circulating in a junction wire between the two electrodes 20 and 21 (principle of coulometry).In the presence of a given volume of the sample Gp contained in the measuring chamber, the measured electrical charge is all the higher as the quantity of exhaled alcohol contained by said sample Gp was large, prior to oxidation. Said electrical charge therefore represents an estimated criterion of the content of exhaled alcohol contained by the gaseous sample Gp, and therefore of the blood alcohol level of the person tested.

[0079] [Fig.2] is a cross-sectional illustration of the analysis apparatus 100 in accordance with [Fig.l], the representation of the electrochemical sensor 50 having been omitted in this [Fig.2]. The cylindrical measuring chamber 3 is located below the measuring electrode 21 and is indicated by a rectangle drawn in dotted lines in [Fig.2]. In a structural arrangement, said electrode 21 materializes a wall of said chamber 3, which can also, of course, have a geometric shape other than that of a cylinder.

[0080] The gas sample Gp flows through a tube 31, flows into an adjacent cavity 15, and then arrives in the pressure chamber 3. The tube 31 and the cavity 15 are located in the internal space of the inlet part 1 and in the internal space of an adjoining connecting part 16, comprising a small-sized part 16.1 and a larger-sized part 16.2, and in a peripheral groove of which a sealing ring 14 is integrated. An additional sealing ring 13, placed on the surface of said part 16 pointing towards the chamber 3, is endowed with elasticity and fulfills the function of a closure seat. A movable closure body 2 is capable of selectively breaking or authorizing, in cooperation with said seat 13, a fluid communication between the cavity 15 and the measuring chamber 3, which fluid communication is established by a fluid guide unit which comprises the tubing 31 and said cavity 15. A valve 2, 13, thus constituted, is shown at the extreme closure location in Figures 2 and 3.

[0081] A rod 4 mechanically connects the shutter body 2 to an electromagnet 7 and runs through the measuring chamber 3 from one side to the other. Said activated electromagnet 7 causes a movement of said rod 4, and therefore of the shutter body 2, more precisely to the left in the example of FIGS. 1 to 3, and thus opens the valve 2, 13. In the deactivated state of said electromagnet 7, a return element (not shown) aims to maintain said valve 2, 13 at the extreme closure location. The activated electromagnet 7 thus overcomes the force of said return element.

[0082] The rod 4 is mechanically connected, in a rigid manner, to a plate 6 connected to one end of a bellows 5. The opposite end of said bellows 5 is connected to an attachment part 10 secured to a wall of the measuring chamber 3. A movement of said plate 6 relative to said part 10 varies the volume of said bellows 5. In the example of Figures 1 and 2, said volume of the bellows 5 is increased when the plate 6 is driven, with respect to the attachment part 10, in a movement having the effect of moving it away from the inlet part 1 and the closure seat 13, that is to say to the right in said example of Figures 1 and 2. Said volume of the bellows 5 is reduced when said plate 6 is moved towards said inlet part 1 and said closure seat 13, that is to say to the left. The bellows 5 is shown filled to a maximum volume in said example of figures 1 and 2.In the case where the volume of said bellows 5 is increased, a gas sample Gp is ​​sucked into the measuring chamber 3 via the inlet part 1, passing through the cavity 15. In the case where said volume of the bellows 5 is again reduced, this sample Gp is ​​expelled from said chamber 3 by passing through said cavity 15 and said part 1.

[0083] [Fig. 3] shows, on an enlarged scale, a detail of [Fig. 2] highlighting the intake part 1, the connecting part 16, the sealing ring 14, the shutter body 2, the shutter seat 13, the rod 4, as well as a part of the measuring chamber 3. The illustration further reveals a part of a side wall 40 pointing towards said intake part 1, and of the covering plate 17 devoted to the measuring chamber 3. The cavity 15 is connected, with reservation of an interstitial space Sp, to a tube 18 surrounding the rod 4. Several intake zones 22.1 and 22.2 connect said tube 18 to said chamber 3. A guide unit 19 guides said rod 4 in said tube 18. The valve 2, 13 is capable of selectively releasing or obscuring the interstitial space Sp. A part of the casing 9 is also shown.

[0084] The obturator body 2 can perform a reciprocating linear movement in the cavity 15. The valve 2, 13 is illustrated at the extreme obturation location in the example of figures 2 and 3, said body 2 then being located between the obturation seat 13 and the inlet part 1. In this concrete form of arrangement, an opening of the valve 2, 13, and a consequent release of the interstitial space Sp, respectively take place due to the fact that the rod 4 moves said body 2 away from said seat 13 and said interstitial space Sp, and towards said inlet part 1. It is also possible to envisage the inverted concrete form of arrangement, in which said seat 13 is located between said body 2 and said part 1. In this inverted form (not shown), a release of the interstitial space Sp results from the fact that said body 2 is moved away from said part 1 and towards the measuring chamber 3.

[0085] [Fig. 4] is a top view of the analysis device 100. Identical reference numerals have the same meanings as in FIGS. 1 to 3. The cover plate 17 covering the measuring chamber 3 is turned towards the observer. An illustration of the housing 9 is confined to a base plate. The rod 4 is guided by means of a sleeve 11 preferably connected, rigidly, to said rod 4 and to the plate 6. A nozzle 30 is placed on the intake part 1. In addition, the illustration schematically shows a control device 60 [control unit] processing signals.

[0086] An optional pressure sensor 12.1, shown schematically, measures the pressure prevailing at a measuring location MP.1 in fluid communication with the cavity 15 and, therefore, in fluid communication with the surrounding space. The same or another pressure sensor 12.2, also shown only schematically, measures the pressure prevailing at a measuring location MP.2 which is in fluid communication with the measuring chamber 3 and which, when the valve 2, 13 is in the closed state, is separated from the surrounding space, and therefore also from the measuring location MP.1, in a fluid-tight manner. In a structural arrangement, the two pressure sensors 12.1 and 12.2 are part of the pressure detection assembly of the exemplary embodiment.

[0087] The control device 60 receives, each time, a signal which emanates from the two pressure sensors 12.1 and 12.2 and on the basis of which it is able to deduce the following information: - depending on the pressure prevailing at the measuring location MP.l, the control device 60 infers the information intended to determine whether the person tested introduces a breath sample A into the mouthpiece 30 and, if so, the start and end of said introduction; - depending on the difference between the time-varying pressures prevailing at the measuring locations MP.l and MP.2, the control device 60 approximately infers the volume flow rate flowing into the measuring chamber 3. On this basis, said device 60 approximately infers the volume of the gas sample Gp contained in said chamber 3. In the case where a person being tested introduces a breath sample A, the pressure prevailing at the location MP.l is generally higher than the ambient pressure since said person being tested generates an overpressure. In the case where no breath sample A is introduced, the pressure prevailing at said location MP.l is equal to said ambient pressure in the exemplary embodiment; - depending on the pressure prevailing at the measurement location MP.2, or on the difference between the time-varying pressures prevailing at the measurement locations MP.1 and MP.2, said device 60 automatically checks whether the valve 2, 13 occupying the extreme closure location is, or is not, capable of effectively closing the interstitial space Sp, which will be explained in more detail below.

[0088] [Fig.5] shows an example of the pressure trend prevailing at the measurement location MP.2. The illustrated time evolution is obtained in a situation in which no breath sample is introduced. The time is plotted on the jç axis, the y axis showing the pressure difference AP [expressed in mbar] between, - on the one hand, the pressure prevailing at the measuring location MP.2, and therefore in the measuring chamber 3, and - the ambient pressure, on the other hand, which pressure is, most often, approximately equal to the pressure prevailing at the MP.L measurement location

[0089] In the structural arrangement just described, a pressure sensor 12.1 measures the pressure prevailing at the measurement location MP.1, a pressure sensor 12.2 measuring the pressure prevailing at the measurement location MP.2. In an alternative arrangement, only the sensor 12.2 dedicated to the pressure prevailing at the location MP.2 is used, while no sensor, dedicated to the pressure prevailing at the location MP.1, is necessary. It is therefore sufficient for the pressure detection assembly to include only one pressure sensor.

[0090] According to the structural arrangement variant, the pressure sensor 12.2 measures the pressure prevailing at the measuring location MP.2 at least once in a situation in which the valve 2, 13 occupies the extreme release location or an intermediate release location. In this situation, the pressure prevailing at the measuring location MP.2 coincides approximately precisely with the ambient pressure. The assumption that said ambient pressure does not vary significantly when the valve 2, 13 is closed or open is generally justified.

[0091] In this example, the valve 2, 13 is specifically arranged in such a way that a movement of the shutter body 2 away from the intake part 1, and towards the measuring chamber 3, causes said valve 2, 13 to move to the extreme shutter location. This form of specific arrangement is shown in Figures 2 and 3, the valve 2, 13 then being illustrated at said extreme shutter location.

[0092] The following description refers to [Fig. 5]. In the initial stage, the same pressure prevails in the measuring chamber 3 as in the surrounding space, so that AP = 0. The valve 2, 13 is located at the extreme release location. At a time tstroke, the regulating drive, the electromagnet 7 for example, causes a suction stroke to be performed. A suction stroke has the effect of increasing the volume of the bellows 5 and of establishing, in the chamber 3, a negative pressure AP reaching up to 150 mbar relative to the surrounding space, which implies that 0 > AP >= -150 mbar. A gas sample Gp is ​​sucked into said chamber 3 by the negative pressure AP. Between the instant tstroke and an instant tclose, the valve 2, 13 is still totally or at least partially open and the pressure, prevailing in said chamber 3, balances with the ambient pressure across the open interstitial space Sp.Until the instant tclose, the volume of said bellows 5 remains unchanged and the shutter body 2 retains the same location with respect to the shutter seat 13. The pressure difference AP remains approximately equal to zero.

[0093] Immediately before the instant tclose, the shutter body 2 is moved relative to the shutter seat 13. The valve 2, 13 occupies the intermediate shutter location at said instant tclose. Due to the elasticity of the seat 13 and other structural parts, the bellows 5 in particular, said body 2 continues its movement somewhat after it has reached said seat 13. The bellows 5 continues in particular to move after the body 2 has reached the seat 13. At the completion of this movement, namely at an instant tfinal, the valve 2, 13 is at the extreme shutter location. The volume of the space defined by the bellows 5 varies between the two instants tclose and tfinal. In the illustrated concrete arrangement form, this effect results in the volume of the space including the measuring chamber 3 and the tube 18 increasing significantly. Since the valve 2, 13 separates this space from the space surrounding, in a fluid-tight manner, this increase in volume results in a drop in the pressure at the measuring location MP.2, by a value APlimit = 5 mbar in the example shown. The ambient pressure, and thus the pressure at the measuring location MP.l, however, remains the same. In the inverted concrete arrangement form, the pressure would increase correspondingly, for example by 5 mbar. This pressure difference AP is maintained in the case where the valve 2, 13 effectively closes the interstitial space Sp permanently, in a fluid-tight manner. This is shown in [Fig.5].

[0094] The control device 60 evaluates the signal from the pressure sensor 12.2 and detects the time tfinal. Said device 60 ensures that the valve 2, 13 maintains the extreme closure location during a verification phase of predetermined minimum duration, namely that no new suction stroke is executed during this verification phase, which is designated by Tmin and begins at said time tfinal. It is possible that said verification phase Tmin overlaps with a phase during which the sensor 50 analyzes the gas sample Gp in the measuring chamber 3.

[0095] The control device 60 checks whether the following conditions are cumulatively satisfied: - the pressure prevailing in the space formed by the measuring chamber 3 and by the tube 18 differs by at least APlimit compared to the ambient pressure; - this applies validly to the entire verification phase Tmin starting at time tfinal and having at least the minimum duration; and - the pressure difference AP remains approximately constant. More precisely: the variation of said difference AP, over time, is within a pre-established variation tolerance spectrum.

[0096] These conditions are valid both for the form of structural arrangement according to figures 2 and 3, in which the valve 2, 13 is closed when the volume of the bellows 5 is increased, and for the inverted form of structural arrangement.

[0097] Preferably, the control apparatus 60 causes the analysis apparatus 100 delivers a message during the verification phase Tmin. A user is thus informed of the fact that said device 100 cannot receive any additional breath samples during this phase Tmin.

[0098] In the event that at least one of the conditions just mentioned is not satisfied, the control device 60 causes the analysis device 100 to trigger an alarm in a form at least perceptible to a human.

[0099] [Fig.6] schematically shows a visualization of the difference between a valve 2, 13 providing fluid-tight closure and a valve showing leaks. Here again, the difference AP relative to the ambient pressure is plotted on the y axis. The APdense pressure pattern appears in the presence of a valve 2, 13 closing with fluid tightness, the APleaky appearance appearing when a valve 2, 13 leaks, in which case it can be seen that the pressure difference AP gradually decreases.

[0100] It is understood that numerous modifications may be made to the invention as described and illustrated, without departing from the scope of the content disclosed herein.

[0101] The elements, objects, indications and information illustrated in the figures are referenced as follows:

[0102] 1: intake part surrounding the tubing 31

[0103] 2: shutter body rigidly connected to the rod 4

[0104] 3: cylindrical measuring chamber receiving the electrochemical sensor 50, delimited by the side wall 40 and by the cover plate 17, in fluid connection with the measuring location MP.2

[0105] 4: rod transmitting a movement from the electromagnet 7 to the plate 6 and to the body shutter 2

[0106] 5: variable volume bellows, connected to the connecting piece 10 on one of the sides and receiving plate 6 on the other side

[0107] 6: plate rigidly connected to the rod 4 and varying the volume of the bellows 5

[0108] 7: electromagnet printing, upon activation, a movement to the rod 4 in direction of the intake part 1 in opposition to the force of a return element

[0109] 9: casing of the analysis device 100

[0110] 10: connecting piece ensuring that the bellows 5 is held at the wall level side 40

[0111] 11: sheath surrounding the rod 4

[0112] 12.1: Pressure sensor measuring the pressure at the MP measurement location. 1

[0113] 12.2: pressure sensor measuring the pressure at the measuring location MP.2

[0114] 13: sealing seat in the form of a sealing ring on the part of link 16

[0115] 14: sealing ring housed in a groove of the connecting piece 16

[0116] 15: cavity located in the connecting part 16, in fluid communication with the MP.l measurement location

[0117] 16: connecting piece which comprises a small-sized part 16.1 and a part 16.2 of higher dimensioning, and surrounds the tube 18

[0118] 16.1: small-sized part of the connecting piece 16, connecting the piece from inlet 1 to tube 18

[0119] 16.2: larger sized part of the connecting piece 16, receiving the sealing ring 14

[0120] 17: cover plate covering the measuring chamber 3

[0121] 18: tube connecting the measuring chamber 3 to the cavity 15, and therefore to the space surrounding, when valve 2, 13 is in the open state

[0122] 19: guide unit guiding the rod 4 in the tube 18

[0123] 20: complementary electrode electrically contacted by wire 33

[0124] 21: measuring electrode electrically contacted by wire 34

[0125] 22.1: admission zone in the measuring chamber 3

[0126] 22.2: admission zone in the measuring chamber 3

[0127] 30: funnel-shaped tip that can be removably placed on the part admission 1 and receiving a breath sample A

[0128] 31: inflow pipe for the gas sample Gp into the cavity 15

[0129] 33: contact wire dedicated to the complementary electrode 20

[0130] 34: contact wire dedicated to the measuring electrode 21

[0131] 40: side wall of the measuring chamber 3

[0132] 50: electrochemical sensor including electrodes 20 and 21, an electrolyte between said electrodes 20 and 21, and the contact wires 33 and 34

[0133] 60: control device processing signals, which controls the electromagnet 7, receives and processes signals from pressure sensors 12.1 and 12.2

[0134] 100: analysis device including the measuring chamber 3, the sensor 50, the electro- magnet 7, bellows 5, plate 6, intake part 1, connecting part 16, housing 9 and control device 60 in a structural arrangement

[0135] A: breath sample having been introduced into the mouthpiece 30 by a person tested

[0136] Gp: gaseous sample consisting of a part of the breath sample and reaching the measuring chamber 3

[0137] MA: median axis

[0138] MP.l: measurement location of the pressure sensor 12.1, in fluid communication with the cavity 15, and therefore in fluid communication with the surrounding space

[0139] MP.2: measurement location of the pressure sensor 12.2, in fluid communication with the measuring chamber 3

[0140] Sp: interstitial space connecting the cavity 15 to the tube 18 and which can be hidden by the valve 2, 13

[0141] APdense: temporal evolution of the pressure difference AP in the presence of a valve 2, 13 causing a closure with fluid tightness

[0142] APleaky: temporal evolution of the pressure difference AP in the presence of a valve 2, 13 showing leaks and not, consequently, causing a blockage with fluid tightness

[0143] AP: pressure difference between, on the one hand, the pressure prevailing in the measuring chamber 3, and therefore at the measuring location MP.2, and the ambient pressure on the other part, at least equal to the minimum gap APlimit in the presence of a valve 2, 13 causing a closure with fluid tightness

[0144] APlimit: minimum difference between the pressure prevailing in the measuring chamber 3 and the ambient pressure, when the valve 2, 13 causes a fluid-tight closure at the extreme closure location

[0145] Tclose: instant at which the shutter body 2 reaches the shutter seat 13 and the valve 2, 13 occupies the intermediate shutter location

[0146] Tfinal: instant at which the valve 2, 13 occupies the extreme closure location, with concomitant start of the verification phase

[0147] Tstroke: time of the start of a suction stroke

[0148] Tmin: verification phase starting at time tfinal, during which the valve 2, 13 remains at the extreme closure location and is subject to a leaktightness check

[0149] Of course, the invention is not limited to the embodiments described and shown in the attached drawings, in particular not to the structural configurations and arrangements mentioned with regard to the apparatuses and methods mentioned. Modifications remain possible, in particular from the point of view of the constitution of the various elements or by substitution of technical equivalents, without departing from the scope of protection of the invention.

Claims

1. Claims Analytical apparatus (100) comprising - a measuring chamber (3), - a gas sensor (50), - a fluid guiding unit (31, 15, Sp, 18, 22.1, 22.2), capable of establishing fluid communication between said measuring chamber (3) and a space surrounding said analysis device (100), - a valve (2, 13), - a pressure detection assembly, provided with at least one pressure sensor (12.1, 12.2), and - a control device (60) processing signals, the valve (2, 13) being able to be brought to an extreme release location, to an intermediate closure location and to an extreme closure location, knowing that said intermediate closure location is located between the two extreme locations, said analysis apparatus (100) being configured or structurally arranged in such a way that, - when the valve (2, 13) occupies the extreme release location, a gas sample (Gp) flows, or can at least flow into the measuring chamber (3), from the surrounding space, passing right through the fluid guide unit (31, 15, Sp, 18, 22.1, 22.2), and that - said fluid guide unit (31, 15, Sp, 18, 22.1, 22.2) is closed when said valve (2, 13) occupies a closing location, a sealing location being the intermediate sealing location, the extreme sealing location or a location between said intermediate sealing location and said extreme sealing location, wherein the gas sensor (50) is configured or structurally arranged to measure the concentration and optionally, or alternatively, the quantity of a pre-established target gas contained by a gas sample (Gp) contained in the measuring chamber (3),

2. knowing that the pressure sensing assembly (12.1, 12.2) is configured or structurally arranged to repeatedly measure the difference (AP) between the pressure prevailing in said measuring chamber (3) and the pressure prevailing in the surrounding space, knowing that the control apparatus (60) is configured or structurally arranged to automatically decide whether or not said valve (2, 13) occupying said extreme closing location actually closes, in a fluid-tight manner, said fluid-guiding unit (31, 15, Sp, 18, 22.1, 22.2), said control apparatus (60) being configured or structurally arranged, for the decision, - to ensure that the valve (2, 13) occupies the extreme closure location, continuously, during a verification phase (Tmin) of a pre-established minimum duration, - to ensure that the pressure detection assembly (12.1, 12.2) repeatedly measures the pressure difference (AP) during said verification phase (Tmin), - to then decide, at a minimum, that said valve (2, 13) actually causes a fluid-tight closure when, during the entirety of said verification phase (Tmin), the pressure prevailing in the measuring chamber (3) differs by at least a pre-established minimum deviation (APlimit) from the ambient pressure, and - to then decide, at a minimum, that said valve (2, 13) does not cause a fluid-tight closure when, at the end of said verification phase (Tmin), the pressure prevailing in said measuring chamber (3) differs, with respect to said ambient pressure, at most by a pre-established fraction of said minimum difference (APlimit). Analysis apparatus (100) according to claim 1, characterized in that the valve (2, 13) comprises a closure seat (13) and a closure body (2) movable relative to said closure seat (13),

3. knowing that said shutter body (2) is applied against said closure seat (13) at each closure location or position, and knowing that said analysis device (100) - is configured or structurally arranged, in a first variant, to ensure that a movement of the shutter body (2) relative to the shutter seat (13), in the direction of the measuring chamber (3), has the effect of bringing the valve (2, 13) to the extreme shutter location, and - is configured or structurally arranged, in a second variant, to ensure that a movement of said shutter body (2) relative to said shutter seat (13), away from said measuring chamber (3), has the effect of bringing said valve (2, 13) to said extreme shutter location. Analysis apparatus (100) according to any one of the preceding claims, characterized in that said analysis apparatus (100) includes a fluid conveying unit (4, 5, 6, 7), which fluid conveying unit (4, 5, 6, 7) is configured or structurally arranged - to suck a gas sample (Gp) into the measuring chamber (3) with a path, from one side to the other, of the fluid guide unit (31, 15, Sp, 18, 22.1, 22.2), and - to rinse said measuring chamber (3) with passage, from one side to the other, of said fluid guide unit (31, 15, Sp, 18, 22.1, 22.2), knowing that the fluid conveying unit (4, 5, 6, 7) is further configured or structurally arranged, in a first variant, - to bring the valve (2, 13) to the extreme release location, during suction, and - to bring said valve (2, 13) to the extreme closure location, during rinsing, and knowing that said fluid conveying unit (4, 5, 6, 7) is further configured or structurally arranged, in a second variant, - to bring the valve (2, 13) to the extreme closing location, during suction, and - to bring said valve (2, 13) to the extreme release location, during rinsing.

4. An analysis apparatus (100) according to claim 3, characterized in that the fluid delivery unit (4, 5, 6, 7) includes a suction chamber unit (5, 6) and an adjustment drive (7), said suction chamber unit (5, 6) providing a chamber (5) with a variable volume, which provided chamber (5) is in fluid communication with the measuring chamber (3), said adjustment drive (7) being configured or structurally arranged to vary the volume of said provided chamber (5), and said analysis apparatus (100) being configured or structurally arranged to ensure that an increase in said provided chamber (5) governs the aspiration of a gas sample (Gp) into said measuring chamber (3).

5. An analysis apparatus (100) according to any one of the preceding claims, characterized in that said analysis apparatus (100) includes an introduction unit (30), which introduction unit (30) is configured or structurally arranged to receive a breath sample (A) from a person being tested, wherein the fluid guiding unit (31, 15, Sp, 18, 22.1, 22.2) is in fluid communication with said introduction unit (30), and wherein said analysis apparatus (100) is configured or structurally arranged to use, as a gaseous sample (Gp), the whole of a breath sample (A) or at least a part of said breath sample (A), which breath sample (A) has been received by said introduction unit (30).

6. Analysis apparatus (100) according to any one of the preceding claims, characterized in that the, or a pressure sensor (12.2) is configured or structurally arranged to measure the pressure at a measurement location (MP.2), which measuring location (MP.2) is located on the fluid guide unit (31, 15, Sp, 18, 22.1, 22.2), more precisely between the valve (2, 13) and the measuring chamber (3), or even in or on said measuring chamber (3), the control device (60) being configured or structurally arranged to ensure that said pressure sensor (12.2) measures the pressure, at said measuring location (MP.2), - on the one hand, repeatedly during the verification phase (Tmin), and - on the other hand, at least once when said valve (2, 13) occupies a release location, knowing that a release location is the extreme release location, or a location located between said extreme release location and the intermediate closure location, and knowing that said control apparatus (60) is, moreover, configured or structurally arranged to determine the ambient pressure as a function of at least one pressure that the pressure sensor (12.2) has measured even while the valve (2, 13) occupied said release location and, preferably, to use this pressure as ambient pressure.

7. Verification apparatus for controlling an analysis apparatus (100), said analysis apparatus (100) to be controlled comprising - a measuring chamber (3), - a gas sensor (50), - a fluid guiding unit (31, 15, Sp, 18, 22.1, 22.2), capable of establishing fluid communication between said measuring chamber (3) and a space surrounding said analysis device (100), and - a soup (2, 13), said valve (2, 13) being able to be brought to an extreme release location, to an intermediate closure location and to an extreme closure location, knowing that said intermediate closure location is located between the two extreme locations, said analysis apparatus (100) being configured or structurally arranged such that, - when the valve (2, 13) occupies the extreme release location, a gas sample (Gp) flows or can flow into the measuring chamber (3), from the surrounding space, passing right through the fluid guide unit (31, 15, Sp, 18, 22.1, 22.2), and that - said fluid guide unit (31, 15, Sp, 18, 22.1, 22.2) is closed when said valve (2, 13) occupies a closing location, a sealing location being the intermediate sealing location, the extreme sealing location or a location between said intermediate sealing location and said extreme sealing location, wherein the gas sensor (50) is configured or structurally arranged to measure the concentration or quantity of a pre-established target gas contained by a gas sample (Gp) contained in the measuring chamber (3), the verification apparatus being configured or structurally arranged to automatically ensure - that the valve (2, 13) occupies the extreme closure location, continuously, during a verification phase (Tmin) of a pre-established minimum duration, - that the difference (AP) between the pressure prevailing in the measuring chamber (3) and the pressure prevailing in the surrounding space is repeatedly measured during said verification phase (Tmin), and - that it be decided whether said valve (2, 13) occupying said extreme closure location causes affectively

8. or not, in a fluid-tight manner, a closure of the fluid guide unit (31, 15, Sp, 18, 22.1, 22.2), the testing apparatus being configured or structurally arranged to then automatically decide, at a minimum, that said valve (2, 13) actually causes a fluid-tight seal when, during the entirety of said verification phase (Tmin), the measured pressure prevailing in the measuring chamber (3) differs by at least a pre-established minimum deviation (APlimit) from the ambient pressure, and said verification apparatus being configured or structurally arranged to then decide, at a minimum, that said valve (2, 13) does not cause any fluid-tight closure when, at least at the completion of said verification phase (Tmin), the pressure prevailing in said measuring chamber (3) differs, with respect to said ambient pressure, at most by a pre-established fraction of said minimum deviation (APlimit). Verification method for controlling an analysis device (100), said analysis device (100) to be controlled comprising - a measuring chamber (3), - a gas sensor (50), - a fluid guiding unit (31, 15, Sp, 18, 22.1, 22.2), capable of establishing fluid communication between said measuring chamber (3) and a space surrounding said analysis device (100), and - a soup (2, 13), said valve (2, 13) being able to be brought to an extreme release location, to an intermediate closure location and to an extreme closure location, knowing that said intermediate closure location is located between the two extreme locations, said analysis apparatus (100) being configured or structurally arranged such that, - when the valve (2, 13) occupies the extreme release location, a gas sample (Gp) flows in or can flow into the measuring chamber (3), from the surrounding space, passing right through the fluid guide unit (31, 15, Sp, 18, 22.1, 22.2), and that - said fluid guide unit (31, 15, Sp, 18, 22.1, 22.2) is closed when said valve (2, 13) occupies a closing location, a sealing location being the intermediate sealing location, the extreme sealing location or a location between said intermediate sealing location and said extreme sealing location, wherein the gas sensor (50) is configured or structurally arranged to measure the concentration or quantity of a pre-established target gas contained by a gas sample (Gp) contained in the measuring chamber (3), said verification method comprising the automatically executed steps of - in that it is ensured that the valve (2, 13) occupies the extreme closure location, continuously, during a verification phase (Tmin) of a pre-established minimum duration, - in that the difference (AP) between the pressure prevailing in the measuring chamber (3) and the pressure prevailing in the surrounding space is repeatedly measured during said verification phase (Tmin), and - in that it is decided whether or not said valve (2, 13) occupying said extreme closure location actually causes, in a fluid-tight manner, a closure of the fluid guide unit (31, 15, Sp, 18, 22.1, 22.2), knowing that it is then decided, at a minimum, that said valve (2, 13) actually causes a fluid-tight closure when, during the entirety of said verification phase (Tmin), the measured pressure prevailing in the measuring chamber (3) differs by at least a pre-established minimum deviation (APlimit) from the ambient pressure, and

9. that it is then decided, at a minimum, that said valve (2, 13) does not cause any fluid-tight closure when, at least at the completion of said verification phase (Tmin), the measured pressure prevailing in said measuring chamber (3) differs, with respect to said ambient pressure, at most by a pre-established fraction of said minimum deviation (APlimit). Analysis method implemented by using an analysis device (100), which analysis device (100) comprises - a measuring chamber (3), - a gas sensor (50), - a fluid guiding unit (31, 15, Sp, 18, 22.1, 22.2), capable of establishing fluid communication between said measuring chamber (3) and a space surrounding said analysis device (100), and - a soup (2, 13), said analysis method including a measurement method and a verification method, knowing that said measuring method comprises the steps consisting of - in that the valve (2, 13) is brought to an extreme release location and releases the fluid guide unit (31, 15, Sp, 18, 22.1, 22.2), - in that a gas sample (Gp) flows into the measuring chamber (3), from the surrounding space, passing right through said fluid guide unit (31, 15, Sp, 18, 22.1, 22.2), - in that said valve (2, 13) is brought to an intermediate closure location and is transferred, in the sequence, to an extreme closure location from said intermediate closure location, - in that said valve (2, 13) closes said fluid guide unit (31, 15, Sp, 18, 22.1, 22.2) from the moment at which it reaches said intermediate closing location, and - in that the gas sensor (50) measures the concentration or quantity of a pre-established target gas contained by a gaseous sample (Gp) contained in the measuring chamber (3), and knowing that said verification method comprises the steps executed automatically, consisting of - in that it is ensured that the valve (2, 13) occupies the extreme closure location, continuously, during a verification phase (Tmin) of a pre-established minimum duration, - in that the difference (AP) between the pressure prevailing in the measuring chamber (3) and the pressure prevailing in the surrounding space is repeatedly measured during said verification phase (Tmin), and - in that it is decided whether or not said valve (2, 13) occupying said extreme closure location actually causes, in a fluid-tight manner, a closure of the fluid guide unit (31, 15, Sp, 18, 22.1, 22.2), knowing that it is then decided, at a minimum, that said valve (2, 13) actually causes a fluid-tight closure when, during the entirety of said verification phase (Tmin), the measured pressure prevailing in the measuring chamber (3) differs by at least a pre-established minimum deviation (APlimit) from the ambient pressure, and that it is then decided, at a minimum, that said valve (2, 13) does not cause any fluid-tight closure when, at least at the completion of said verification phase (Tmin), the pressure prevailing in said measuring chamber (3) differs, with respect to said ambient pressure, at most by a pre-established fraction of said minimum difference (APlimit).

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