ES3014713T3 - Container for pressurised gas provided with an electronic clamping alert device - Google Patents

Abstract

The invention relates to a pressurized gas container (1), in particular a gas cylinder, comprising an internal volume (2) for storing pressurized gas, a fluid distribution valve (3) comprising a flow outlet connector (11) to which a flexible gas line (100) is connected, a flow selection device (12) for selecting a desired gas flow rate (Qd) to be supplied by the flow outlet connector (11), a pressure sensor (4) for measuring the gas pressure at several successive times (t1, t2), and providing pressure measurements (p1, p2) corresponding to the gas pressure measured at said successive times (t1, t2), and microprocessor control means (5) configured to process the pressure measurements (p1, p2) provided by the pressure sensor to detect any pinching of the flexible gas line (100) and alert in case of pinching. (Automatic translation with Google Translate, without legal value)

Description

DESCRIPTION

Pressurized gas container provided with an electronic pinch warning device

The invention relates to a pressurized gas container, in particular a gas cylinder, equipped with a fluid distribution valve comprising an electronic device with a digital display configured to detect pinching of the gas distribution conduit and activate, if necessary, a pinch alert which, in particular, displays on the digital display, for example, a dedicated pinch alert icon.

Medical gases, such as oxygen, NO/N<2> mixtures, NO/O<2>, He/O<2>, medical air, or similar, are generally packaged in pressurized gas containers, such as cylinders or canisters. These gas containers are equipped with a distribution valve, with or without an integrated expansion system, used to supply the medical gas, and with a needle or digital pressure gauge indicating the residual gas pressure. The valve and gauge are usually protected by a protective cap, also called a "lid," which protects them from impacts, falls, dirt, etc.

Thus, document EP-A-2918893 proposes a gas cylinder of this type equipped with a valve with an integrated pressure reducer or RDI and a mechanical needle pressure gauge, while document EP-A-2918892 proposes a gas cylinder equipped with an electronic device with a digital display screen.

A gas cylinder is also known from document FR3070592A1.

To utilize the gas, i.e., to extract it from the container, it is common practice to connect a flexible gas line, such as a plastic hose, to the flow outlet connector of the distribution valve through which the gas is supplied. The gas can then be delivered through this flexible gas line to a patient who requires it as part of a gas inhalation treatment. Typically, the gas is medical oxygen, delivered to the patient through a respiratory interface, such as a mask, nasal cannula, or others.

Now, it often happens that the flexible gas line, which is usually a flexible tube, is more or less pinched, i.e. crushed, twisted or bent, so that the actual gas flow sent to the patient is not the desired one, in particular it is (very) insufficient in relation to what is needed to treat the patient.

These pinches of the flexible gas line, i.e. the flexible tube that supplies gas to patients confined to mechanical and/or electric beds, are recurrent and cause a decrease in the flow of gas, usually oxygen, supplied to the patients, which can cause desaturation (i.e. a decrease in the concentration of O<2> in the blood) and, in the worst cases, cause hypoxemic cardiac arrest and the death of some patients.

However, since a bedridden patient is often not awake enough to notice a significant change in oxygen flow, and since a blood gas monitor only alerts when the patient is already desaturated and therefore in danger, it is preferable to warn the user in advance that the treatment the patient is receiving is different from the prescribed treatment.

In other words, it is easy to understand that clamping causes a safety issue in patient treatment, since, in the event of significant clamping of the gas line, the patient cannot be treated effectively due to a lack of gas, which is usually oxygen, resulting in desaturation or even worse.

The challenge is therefore to be able to automatically and as quickly as possible detect any pinching, in particular any major pinching, of the flexible gas line, typically a flexible plastic tube, connected to the flow outlet connection of a gas distribution valve installed on a gas container, and to immediately alert the user in response to such pinch detection.

The solution of the invention relates to a pressurized gas container, as described in claim 1.

According to the embodiment considered, the container of the invention may comprise one or more of the following characteristics:

- the control means are or comprise a control device comprising one or more microprocessors, such as an electronic card.

- the control means are configured to activate a pinch alert when any of the following conditions are met: Qr < n . Qd with: n < 0.70 (i.e. 70%), preferably with < 0.60 (i.e. 60%).

- the control means are configured to activate a pinch alert when any of the following conditions are met: Qr < n . Qd with: n < 0.50 (i.e. 50%).

- the microprocessor control means are configured to determine the actual gas flow rate (Qr) between successive instants (t<1>, t<2>), performing the following calculation (the values are expressed in units of the International System of Units):

where:

AP is the pressure variation between two successive pressure measurements (p<1>, p<2>),

V corresponds to the volume of the gas container, and

At corresponds to the variation in time between the successive instants ((t<1>, t<2>) in which the two successive pressure measurements were taken (p<1>, p<2>).

- the control means are arranged in the housing of an electronic device.

- The electronic device is a digital pressure gauge that allows determining the gas pressure and/or its autonomy.

- The flow rate selection device allows the selection of the desired gas flow rates (Qd) between 0 and 25 l/min.

- The flow selection device also collaborates with a flow adjustment device arranged in the valve body in order to adjust the flow rate to the desired gas flow rate value (Qd).

- the flow adjustment device comprises a disc with calibrated holes arranged in the gas path in the valve body.

- the gas outlet connection is arranged in the center of the rotating flywheel, i.e. they are arranged coaxially with each other.

- includes a time counter.

- the time counter is incorporated into the control means.

- the control means are configured to record the successive times (t<1>, t<2>) at which the successive pressure measurements (p<1>, p<2>) are taken.

- the control means are configured to determine the time (At) that elapses between two successive instants (t^ t2).

- preferably, the two successive instants (t<1>, t<2>) are separated by a time between 1 and 60 seconds, or more preferably, less than 30 seconds, for example, of the order of 10 seconds.

- the container has an internal volume between 1 and 20 l, typically between 2 and 15 l (water equivalent). - the digital display of the electronic device is configured to show a pinch alert icon or an alphanumeric pinch indication when a pinch alert is triggered, for example, the terms "CLAMP", "CLAMPAGE" or similar (in French or another language).

- microprocessor control means include one or more microprocessors.

- The microprocessor control means are configured to additionally activate an audible alarm if a pinch alert is triggered.

- the data storage means comprise a read-only memory, preferably EEPROM or similar.

- the electronic device is fixed to the gas distribution valve.

- the electronic device comprises the microprocessor.

- at least one source of electrical power supplies the digital display, the microprocessor(s) and/or the pressure sensor.

- The pressure sensor is arranged to measure the gas pressure within the internal gas passage of the fluid distribution valve.

- the fluid distribution valve is protected by a protective cap comprising a rigid body arranged around said fluid distribution valve.

- the housing of the electronic device, which includes the digital display, is housed in an opening provided in the body of the cap.

- The cap body defines an internal volume sized to accommodate the gas distribution valve. - The power source comprises one or more rechargeable or non-rechargeable batteries.

- the microprocessor or microprocessors use one or more algorithms.

- the microprocessor control means include an electronic card on which the microprocessor(s) are arranged.

- The microprocessor control means include at least one microcontroller. More specifically, one (or more) microprocessors can be integrated into the electronic device in the form of a microcontroller.

- Microprocessor control means, which are usually microcontrollers, are configured to record data, in particular within a computer program or algorithm.

- the cap body is made of polymeric material, metal or other combination of materials.

- the body of the cap comprises one (or more) carrying handles, preferably arranged so as to extend beyond the cap, i.e., essentially located above it.

- The gas distribution valve is a valve with an integrated pressure reducer or RDI.

- The fluid distribution valve is made of a copper alloy, such as brass.

- The body of the cap also comprises a fixing system designed to allow its fixing to a support, in particular to a bar of a hospital bed or to a patient transport stretcher or similar.

- the body of the cap also comprises a mobile, preferably pivoting, fixing system.

- The fluid container is a pressurized gas cylinder containing a pressurized gas, particularly a medical gas such as oxygen.

- When full, the fluid container contains a gas at a pressure of at least 130 to 200 bar ABS, or even at least 300 bar ABS.

- the fluid container is generally cylindrical in shape, in particular ogival, and is made of metal or metal alloy (e.g. steel, aluminium, etc.) or composite material(s).

- the fluid container contains a gas or gas mixture, such as oxygen, a NO/N<2>, O<2>/N<2>O or He/O<2> mixture, air or others.

The invention will now be better understood thanks to the following detailed description, given for illustrative but not restrictive purposes, with reference to the attached figure, in particular:

Fig. 1 is a schematic diagram of a gas container with digital display, according to the invention.

Fig. 2 shows an embodiment of a gas container provided with an electronic device with digital display according to the invention.

Fig. 3 illustrates the clamping of a flexible gas line connected to the gas valve of a gas container according to the invention.

Fig. 4 shows an embodiment of an electronic device with digital display of a gas container according to the invention.

Fig. 1 is a schematic diagram of a pressurized gas container 1 according to the invention, specifically in this case a gas cylinder with axis AA, while Fig. 2 shows an embodiment of such a gas container 1.

The gas container 1 of Figs. 1 and 2 comprises an internal volume 2 for storing pressurized gas, for example at more than 200 bar abs (maximum pressure), and is equipped with a fluid distribution valve 3, such as an RDI, through which at least one internal gas passage passes in fluid communication with the internal volume 2 of the container 1 to convey the gas within the body of the gas distribution valve 3 to a flow outlet connection 11 to which a flexible gas line 100, shown schematically in Fig. 3, is fluidly connected.

Preferably, the fluid container 1 is a gas cylinder of axis AA comprising a cylindrical body defining the internal volume 2 for storing high-pressure gas, typically with a maximum pressure of between 130 and 300 bar abs, or even above 300 bar abs, and a neck comprising an orifice communicating with the internal volume 2 and allowing gas to be extracted from the internal volume 2 or, conversely, to be filled when empty. The gas distribution valve 3 is mounted, typically screwed, in the orifice in the neck of the gas cylinder.

As explained below, the gas distribution valve 3 comprises a gas distribution connection or tap, called flow outlet connection 11, to which a flexible gas line 100 can be connected, such as a flexible plastic tube, which is used to transport the gas to a medical apparatus or device that uses the gas supplied by the valve 3, for example, a respiratory mask that distributes gas to a patient at a flow rate prescribed by a doctor or similar corresponding to a treatment to be followed.

The gas distribution valve 3 comprises a pressure sensor 4 for measuring the gas pressure within the internal gas passage and/or in the internal volume 2 of the container 1 and supplying pressure measurements (i.e. measurement signals) to the microprocessor control means 5, i.e. a control device or unit comprising one or more microprocessors implementing one or more algorithms, for example an electronic card including one or more microprocessors implementing one or more calculation or other algorithms, preferably a microcontroller.

The microprocessor control means 5, configured to process the pressure measurements supplied by the pressure sensor 4. They are preferably arranged in the housing of an electronic device 7, for example a digital pressure gauge, fixed to the fluid distribution valve 3, comprising a digital display 6, such as an LCD screen or similar.

In addition, a user-operable flow rate selection device 12 is provided, such as a rotary handwheel, which is used to select a desired gas flow rate (Qd) to be supplied through the flow rate outlet connection 11, for example, to fulfill a prescription from a physician or the like.

As illustrated in Fig. 2, the flow rate selection device 12 may be a rotating handwheel capable of rotating between several angular positions, offset from each other, each corresponding to a given flow rate value. For example, gas flow rate values between 0 l/min and 30 l/min, typically between 0 and 25 l/min, may be selected. For example, the flow rate values that may be selected are as follows: For example, the flow rate values that may be selected are as follows: 0, 0.5, 1.2, 3, 5, 8, 10, 12, 15, 20, 22 and 25 l/min, or any other value.

As can be seen, the desired flow rate value (Qd) selected by the user by actuating the flow rate selection device 12, i.e. the rotary handwheel, appears in a reading window 13 located above the flow rate selection device 12, which is normally a reading window 13 or a cut-out provided in the protective cap 14 arranged around the valve 3 and used to protect it against knocks or other external aggressions.

In fact, the flow rate selection device 12 also cooperates with a flow rate adjustment device arranged in the valve body 3 in order to adjust the flow rate to the desired gas flow rate value (Qd). For example, the flow rate adjustment device may be a disc with calibrated holes arranged in the gas path in the valve body 3. Such an arrangement is known per se.

Once the desired gas flow rate (Qd) has been selected, the position of the flow selection device 12, for example, the angular position of the rotating handwheel, can be determined using one or more position sensors. This allows the control means 5 to determine the value of the desired gas flow rate (Qd) that has been selected. Such an arrangement is also known per se.

In the embodiment of Fig. 2, the flow outlet connection 11 is arranged centrally and coaxially with the flow selection rotary handwheel 12; however, they could also be separated from each other according to other possible embodiments (not shown).

On the other hand, the pressure sensor 4 is configured and arranged to measure the pressure of the gas at several successive instants (t<1>, t<2>), for example, spaced at successive instants ((t<1>, t<2>) of a duration of a few seconds to tens of seconds, for example, of the order of 10 seconds, and then supply the pressure measurements (p<1>, p<2>) taken which correspond to the pressure of the gas measured at these successive instants (t<1>, t<2>).

The time elapsed between successive instants ((t<1>, t<2>)) can be determined by means of a time counter, for example, internal to the microprocessor control means 5.

The pressure measurements (p<1>, p<2>) made and transmitted by the sensor 14 are, in reality, signals representing pressure values or other magnitudes, such as voltage or current values, corresponding to said pressure values.

Alternatively, the microprocessor control means 5 are configured to process the pressure measurement signals (p<1>, p<2>) determined at successive times (t<1>, t<2>) and supplied by the pressure sensor 4, which measures the pressure of the gas stored in the container 1, and to determine the measured pressure values from these measurement signals.

More specifically, these pressure measurements are then processed by the control means 5 to determine, from the pressure measurements (p<1>, p<2>) taken at successive instants (t<1>, t<2>), an actual gas flow rate (Qr) supplied by the flow outlet connection 11 from the valve 3 to the flexible gas line 100, between the successive times (t<1>, t<2>).

This actual gas flow rate (Qr) is then compared with the desired gas flow rate (Qd), set by actuating the flow rate selection device 12, and a clamping alert is triggered when it is deduced from this comparison that the actual gas flow rate (Qr) is much lower than the expected gas flow rate, that is to say the desired gas flow rate (Qd) or, in other words, when: Qr < n. Qd with: n < 0.80 (that is to say 80% expressed as a percentage), preferably n < 0.70 (that is to say 70%), even more preferably with < 0.60 (that is to say 60%), advantageously n < 0.50 (that is to say 50%).

To determine the actual gas flow rate (Qr), between successive instants (t<1>, t<2>), from successive pressure measurements (p<1>, p<2>), the control means 5 perform the following calculation: Qr = (AP . V) / At where:

- AP is the pressure variation between two successive pressure measurements (p<1>, p<2>),

- V is the volume of the gas container, and

- At corresponds to the variation in time between the successive instants (t<1>, t<2>) in which the two successive pressure measurements were taken ((p<1>, p<2>).

The internal volume of the gas container (in water equivalent) is a known value which can be stored in the storage means 9, such as a computer memory of the EEPROM type, of the electronic device 7. For example, gas cylinders equipped with this type of electronic device 7 used for distributing medical oxygen (i.e. medical grade) typically have volumes between 1 and 20 liters (water equivalent), typically between 2 and 15 liters, for example, depending on the cylinder considered, the volume can be of the order of 2 l, 3.5 l, 4.6 l, 5 l, 7 l, 10 l, 11 l or 15 l.

The storage means 9 may also record other data, such as the time elapsed between successive instants (t<1>, t<2>), successive pressure measurements (p<1>, p<2>), etc., as well as other parameters, such as the gas temperature, the ambient temperature, the position of the selector, the configuration of the cylinder, the filling pressure, the confirmation button presses, the alerts, etc.

More generally, the electronic device 7, for example a digital pressure gauge comprising the microprocessor control means 5, normally an electronic card, is housed in an opening or casing provided in the body of the protective cap 14 arranged around the fluid distribution valve 3 and used to protect it against knocks or other possible damage, for example a rigid cap made of polymer and/or metal, as illustrated in Fig. 2.

The digital display 6 of the electronic device 7 comprises a digital display, for example a liquid crystal display (LCD) or the like, which is located in the rigid housing, in particular on the front face 18, of the electronic device 7, as illustrated in Fig. 4. It is electrically powered by a (non-visible) electrical power source arranged in the cap 14, for example one or more batteries or cells arranged in a battery compartment provided in the wall of the cap body and closed by a removable flap or the like.

In the event of a pinching of a conduit 100 being detected, the control means 5 are configured to activate a visual and/or audible alert in order to warn the user of this pinching. Fig. 3 illustrates a pinching of a flexible gas conduit 100 connected to the gas valve of a gas container, according to the invention (not shown). As can be seen, the object 102 pressing the flexible gas conduit 100 locally deforms 101 its flexible wall, i.e., crushes it. This then causes a pinching, i.e., a restriction of the passage resulting in a drop in flow rate. Other forms of pinching exist, such as a bent tube, i.e., forming an elbow or the like.

In the event of a pinch being detected, as illustrated in Fig. 4, the activation of a visual alert can be specified by displaying on the display screen 6 a specific alert icon 10, for example, in this case, a warning triangle, and/or an alphanumeric indication 20 of pinching, for example, in this case, the term "CLAMP" or another equivalent term, such as CLAMPAGE, whether in French or in another language, for example, CLAMPING in English.

The activation of an alert may also be accompanied by the emission of a sound and/or light signal, for example, a flashing of the display screen 6 or of one (or more) alert diodes 19 present in the housing of the electronic device 7.

Thanks to the present invention, it is possible to prevent an insufficient flow of gas from being supplied to a patient, for example a flow rate that does not comply with a medical prescription, i.e. to immediately detect any pinching of the flexible gas line fluidly connected to the flow outlet connection 11 of the valve 3.

It should be noted that the digital display 6 of the electronic device 7 can also show other useful information, for example the value of the desired or actual gas flow rate Qd or Qr (in l/min or other unit), as illustrated in Fig. 4, or even the gas autonomy (in hours and minutes), for example represented by a bar graph 22.

More generally, the digital display 6 has a height, for example, between approximately 29 and 37 cm and a width, for example, between approximately 39 and 43 cm.

The digital display 6 can be arranged on the front panel 18, i.e. the front facade, of the housing of the electronic device 7, which is fixed to the fluid distribution valve 3 and can be housed in an opening of the body of the protective cap 14 that protects the valve 3.

The electronic device 7 may also include an alert confirmation button 21, in particular arranged on its front panel 18, which is used to confirm or stop an alert after its activation.

Furthermore, as illustrated in Fig. 2, the protective cap 14 may be a simple cap, such as a rigid protective sleeve or cover without any other functionality, or it may be more advanced, i.e. it may include other functionalities, such as, for example, a carrying handle 15 fixed to the body of the cap 14 by one or more support posts 16, and/or a mobile (e.g., pivoting or translating) or fixed fixing system 17 that allows to fix, i.e., to suspend the container/valve/cap assembly from a support, which may be a bed or stretcher bar, or any other similar bar.

The carrying handle 15 is advantageously sized to be manually grasped by a user to allow easy handling and/or transport of the gas container/valve/cap assembly.

All components that require electrical power to operate (i.e., the microprocessor, the sensor, the display, etc.) are supplied with electrical power by means of an electrical power source arranged, for example, in the cap 14, for example, an electric cell or battery.

Generally speaking, a fluid container 1, in particular a gas bottle, equipped with a valve, such as an RDI, protected by a cap according to the invention, is suitable for storing and supplying pressurized gas, in particular a medical gas or a gas mixture, such as oxygen, a mixture of NO/N<2>, O<2>/N<2>O or He/O<2>, air or the like.

Claims (9)

1. Pressurized gas container (1), in particular a gas cylinder, comprising an internal pressurized gas storage volume (2) and further comprising: - a fluid distribution valve (3) having a flow outlet connection (11) to which a flexible gas line (100) is connected. - A flow selection device (12) that allows selecting a desired gas flow rate (Qd) to be supplied through the flow outlet connection (11), the flow selection device (12) comprising a rotating handwheel configured to move between several positions angularly displaced from each other, each position corresponding to a certain desired gas flow rate value (Qd) comprised between 0 and 30 l/min, the desired flow rate value (Qd) being selected by the user by actuating the rotating handwheel. - a pressure sensor (4) for measuring the gas pressure at several instants (t<1>, t<2>), and providing pressure measurements (p<1>, p<2>) corresponding to the gas pressure measured at said successive instants (t<1>, t<2>), and - microprocessor control means (5) configured to process the pressure measurements (p<1>, p<2>) supplied by the pressure sensor (4). characterized in that the control means (5) are arranged in an electronic device (7) with a digital display (6) fixed to the fluid distribution valve (3) and are also configured to: a) determining an actual gas flow rate (Qr) supplied by the flow outlet connection (11) from the valve to the flexible gas line (100) between successive instants (t<1>, t<2>), from the pressure measurements (p<1>, p<2>) made at the successive instants (t<1>, t<2>), b) compare the actual gas flow rate (Qr) with the desired gas flow rate (Qd), c) activate a pinch alert when: Qr < n . Qd with: n < 0.80. 2. Container according to claim 1, characterized in that the control means (5) are configured to activate a pinch alert when: Qr < n. Qd with: n < 0.70. 3. Container according to one of the preceding claims, characterized in that the control means (5) are configured to activate a pinch alert when: Qr < n. Qd with: n < 0.60. 4. Container according to one of the preceding claims, characterized in that the control means (5) are configured to activate a pinch alert when: Qr < n. Qd with: n < 0.50. 5. Container according to one of the preceding claims, characterized in that the control means (5) are configured to determine the actual gas flow rate (Qr) between successive instants (t<1>, t<2>), performing the following calculation: Qr = (AP . V) / At where: - AP is the pressure variation between two successive pressure measurements (p<1>, p<2>), - V is the volume of the gas container, and - At corresponds to the variation in time between the successive instants (t<1>, t<2>) in which the two successive pressure measurements were taken (p<1>, p<2>). 6. Container according to claim 1, characterized in that the digital display (6) of the electronic device (7) is configured to display a pinch alert icon (10) and/or an alphanumeric pinch indication (20) in case of activation of a pinch alert. 7. Container according to claim 1, characterized in that the pressure sensor (4) is arranged to measure the gas pressure within the internal gas passage of the gas distribution valve (3) in fluid communication with the internal volume (2) of the gas container (1). 8. Container according to claim 1, characterized in that the electronic device (7) is fixed to the gas distribution valve (3) and is electrically powered by an electrical energy source, preferably one or more batteries. 9. Use of a gas container (1), in particular a gas cylinder, according to one of the preceding claims, for storing or supplying a pressurized gas, in particular a medical gas chosen from oxygen or a gas mixture N<2>O/O<2>, NO/N<2>, He/O<2>, medical air.