US20190269875A1 - Gas Flow Indicator Device - Google Patents
Gas Flow Indicator Device Download PDFInfo
- Publication number
- US20190269875A1 US20190269875A1 US16/392,705 US201916392705A US2019269875A1 US 20190269875 A1 US20190269875 A1 US 20190269875A1 US 201916392705 A US201916392705 A US 201916392705A US 2019269875 A1 US2019269875 A1 US 2019269875A1
- Authority
- US
- United States
- Prior art keywords
- housing
- gas flow
- indicator
- concealment
- gas
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Abandoned
Links
Images
Classifications
-
- A—HUMAN NECESSITIES
- A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
- A61M—DEVICES FOR INTRODUCING MEDIA INTO, OR ONTO, THE BODY; DEVICES FOR TRANSDUCING BODY MEDIA OR FOR TAKING MEDIA FROM THE BODY; DEVICES FOR PRODUCING OR ENDING SLEEP OR STUPOR
- A61M16/00—Devices for influencing the respiratory system of patients by gas treatment, e.g. mouth-to-mouth respiration; Tracheal tubes
- A61M16/10—Preparation of respiratory gases or vapours
- A61M16/12—Preparation of respiratory gases or vapours by mixing different gases
- A61M16/122—Preparation of respiratory gases or vapours by mixing different gases with dilution
- A61M16/125—Diluting primary gas with ambient air
-
- A—HUMAN NECESSITIES
- A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
- A61M—DEVICES FOR INTRODUCING MEDIA INTO, OR ONTO, THE BODY; DEVICES FOR TRANSDUCING BODY MEDIA OR FOR TAKING MEDIA FROM THE BODY; DEVICES FOR PRODUCING OR ENDING SLEEP OR STUPOR
- A61M16/00—Devices for influencing the respiratory system of patients by gas treatment, e.g. mouth-to-mouth respiration; Tracheal tubes
- A61M16/0003—Accessories therefor, e.g. sensors, vibrators, negative pressure
-
- A—HUMAN NECESSITIES
- A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
- A61M—DEVICES FOR INTRODUCING MEDIA INTO, OR ONTO, THE BODY; DEVICES FOR TRANSDUCING BODY MEDIA OR FOR TAKING MEDIA FROM THE BODY; DEVICES FOR PRODUCING OR ENDING SLEEP OR STUPOR
- A61M16/00—Devices for influencing the respiratory system of patients by gas treatment, e.g. mouth-to-mouth respiration; Tracheal tubes
- A61M16/06—Respiratory or anaesthetic masks
- A61M16/0683—Holding devices therefor
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01F—MEASURING VOLUME, VOLUME FLOW, MASS FLOW OR LIQUID LEVEL; METERING BY VOLUME
- G01F1/00—Measuring the volume flow or mass flow of fluid or fluent solid material wherein the fluid passes through a meter in a continuous flow
- G01F1/05—Measuring the volume flow or mass flow of fluid or fluent solid material wherein the fluid passes through a meter in a continuous flow by using mechanical effects
- G01F1/20—Measuring the volume flow or mass flow of fluid or fluent solid material wherein the fluid passes through a meter in a continuous flow by using mechanical effects by detection of dynamic effects of the flow
- G01F1/28—Measuring the volume flow or mass flow of fluid or fluent solid material wherein the fluid passes through a meter in a continuous flow by using mechanical effects by detection of dynamic effects of the flow by drag-force, e.g. vane type or impact flowmeter
-
- A—HUMAN NECESSITIES
- A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
- A61M—DEVICES FOR INTRODUCING MEDIA INTO, OR ONTO, THE BODY; DEVICES FOR TRANSDUCING BODY MEDIA OR FOR TAKING MEDIA FROM THE BODY; DEVICES FOR PRODUCING OR ENDING SLEEP OR STUPOR
- A61M16/00—Devices for influencing the respiratory system of patients by gas treatment, e.g. mouth-to-mouth respiration; Tracheal tubes
-
- A—HUMAN NECESSITIES
- A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
- A61M—DEVICES FOR INTRODUCING MEDIA INTO, OR ONTO, THE BODY; DEVICES FOR TRANSDUCING BODY MEDIA OR FOR TAKING MEDIA FROM THE BODY; DEVICES FOR PRODUCING OR ENDING SLEEP OR STUPOR
- A61M16/00—Devices for influencing the respiratory system of patients by gas treatment, e.g. mouth-to-mouth respiration; Tracheal tubes
- A61M16/0003—Accessories therefor, e.g. sensors, vibrators, negative pressure
- A61M2016/003—Accessories therefor, e.g. sensors, vibrators, negative pressure with a flowmeter
-
- A—HUMAN NECESSITIES
- A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
- A61M—DEVICES FOR INTRODUCING MEDIA INTO, OR ONTO, THE BODY; DEVICES FOR TRANSDUCING BODY MEDIA OR FOR TAKING MEDIA FROM THE BODY; DEVICES FOR PRODUCING OR ENDING SLEEP OR STUPOR
- A61M2202/00—Special media to be introduced, removed or treated
- A61M2202/02—Gases
- A61M2202/0208—Oxygen
-
- A—HUMAN NECESSITIES
- A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
- A61M—DEVICES FOR INTRODUCING MEDIA INTO, OR ONTO, THE BODY; DEVICES FOR TRANSDUCING BODY MEDIA OR FOR TAKING MEDIA FROM THE BODY; DEVICES FOR PRODUCING OR ENDING SLEEP OR STUPOR
- A61M2205/00—General characteristics of the apparatus
- A61M2205/58—Means for facilitating use, e.g. by people with impaired vision
- A61M2205/583—Means for facilitating use, e.g. by people with impaired vision by visual feedback
- A61M2205/585—Means for facilitating use, e.g. by people with impaired vision by visual feedback having magnification means, e.g. magnifying glasses
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01F—MEASURING VOLUME, VOLUME FLOW, MASS FLOW OR LIQUID LEVEL; METERING BY VOLUME
- G01F15/00—Details of, or accessories for, apparatus of groups G01F1/00 - G01F13/00 insofar as such details or appliances are not adapted to particular types of such apparatus
- G01F15/06—Indicating or recording devices
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01F—MEASURING VOLUME, VOLUME FLOW, MASS FLOW OR LIQUID LEVEL; METERING BY VOLUME
- G01F15/00—Details of, or accessories for, apparatus of groups G01F1/00 - G01F13/00 insofar as such details or appliances are not adapted to particular types of such apparatus
- G01F15/06—Indicating or recording devices
- G01F15/065—Indicating or recording devices with transmission devices, e.g. mechanical
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01F—MEASURING VOLUME, VOLUME FLOW, MASS FLOW OR LIQUID LEVEL; METERING BY VOLUME
- G01F15/00—Details of, or accessories for, apparatus of groups G01F1/00 - G01F13/00 insofar as such details or appliances are not adapted to particular types of such apparatus
- G01F15/14—Casings, e.g. of special material
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01L—MEASURING FORCE, STRESS, TORQUE, WORK, MECHANICAL POWER, MECHANICAL EFFICIENCY, OR FLUID PRESSURE
- G01L7/00—Measuring the steady or quasi-steady pressure of a fluid or a fluent solid material by mechanical or fluid pressure-sensitive elements
- G01L7/16—Measuring the steady or quasi-steady pressure of a fluid or a fluent solid material by mechanical or fluid pressure-sensitive elements in the form of pistons
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01L—MEASURING FORCE, STRESS, TORQUE, WORK, MECHANICAL POWER, MECHANICAL EFFICIENCY, OR FLUID PRESSURE
- G01L7/00—Measuring the steady or quasi-steady pressure of a fluid or a fluent solid material by mechanical or fluid pressure-sensitive elements
- G01L7/16—Measuring the steady or quasi-steady pressure of a fluid or a fluent solid material by mechanical or fluid pressure-sensitive elements in the form of pistons
- G01L7/166—Measuring the steady or quasi-steady pressure of a fluid or a fluent solid material by mechanical or fluid pressure-sensitive elements in the form of pistons with mechanical transmitting or indicating means
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01P—MEASURING LINEAR OR ANGULAR SPEED, ACCELERATION, DECELERATION, OR SHOCK; INDICATING PRESENCE, ABSENCE, OR DIRECTION, OF MOVEMENT
- G01P13/00—Indicating or recording presence, absence, or direction, of movement
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01P—MEASURING LINEAR OR ANGULAR SPEED, ACCELERATION, DECELERATION, OR SHOCK; INDICATING PRESENCE, ABSENCE, OR DIRECTION, OF MOVEMENT
- G01P13/00—Indicating or recording presence, absence, or direction, of movement
- G01P13/0006—Indicating or recording presence, absence, or direction, of movement of fluids or of granulous or powder-like substances
- G01P13/0013—Indicating or recording presence, absence, or direction, of movement of fluids or of granulous or powder-like substances by using a solid body which is shifted by the action of the fluid
Definitions
- the present invention relates generally to gas monitoring device. More particularly, the present invention relates to gas flow indicator device for gas delivery devices or systems and gas supply conduits.
- gas flow indicator device for medical devices, systems or conduits that deliver breathing gas to an individual's airway.
- present invention is not limited solely to that use.
- gas flow indicator device of the invention could include breathing gas delivery devices or systems and gas supply conduits for use in the aviation industry.
- gas flow indicator device of the invention could be used for other, non-breathing gas applications, and the invention should not be construed as limited to any one or more of the specific examples provided herein.
- gas refers to any suitable gas, mixture of gases, vapour or a gas/vapour mixture that, as such, can be monitored using the gas flow indicator device of the invention.
- a gas with which the flow indicator device can be used can entrain an aerosol.
- gas refers to any suitable breathing gas, generally oxygen, a mixture of oxygen and inert gas and/or pharmacological agent, air and oxygen-enriched air.
- gas delivery device refers to any suitable device, system and conduit for supplying gas to, or at, a desired location such as, in the context of a medical or other respiratory application, to or into an individual's airway.
- suitable device, devices, system or conduit include, but are not limited to face masks, mouth pieces, nasal cannulas and gas supply conduits.
- suitable device, devices, systems and conduits may include manual resuscitator devices, such as, for example, bag valve masks and endotracheal tubes.
- Supplemental gas is widely used in the medical field.
- supplemental oxygen is used to assist or maintain safe blood oxygen levels for a patient.
- the duration of supply of supplemental oxygen varies, depending on the condition of the patient and/or the particular circumstance necessitating supplemental oxygen being administered. Common scenarios include patients having a cardiorespiratory disease or dysfunction and surgical/anaesthetic intervention that mandates supplementation of atmospheric air with higher concentrations of inspired oxygen in order to achieve normal oxygen tensions in the patient's blood. Failure to deliver supplemental oxygen can lead to risk of reduced arterial oxygen tension that, if not corrected, can contribute directly to increased morbidity and mortality.
- gas delivery mask or oxygen mask.
- oxygen mask One of the most commonly used gas delivery devices for spontaneously breathing patients is the gas delivery mask, or oxygen mask.
- the “Hudson Mask” is made of a clear plastics material and include a body that is sized to seat over the nose and mouth of a patient.
- gas is introduced through a gas inlet, and expiratory gases are vented from either around the side of the mask or through appropriately placed ventilation apertures.
- Gas is supplied to the gas inlet from a gas supply source, commonly by way of a length of clear plastic conduit.
- the gas supply source may be an in-built hospital supply source, or a gas tank or cylinder.
- Oxygen masks usually are designed to increase a patient's inspired fraction of oxygen, such as from about 21% to about 40%.
- the oxygen flow rate required to achieve this is about 6 litres per minute (“6 L/min”).
- 6 L/min 6 litres per minute
- the patient re-breathes their expired gases which can't be replenished satisfactorily by entrainment of air around the side of the mask, ultimately leading to the inspiration of a gas mixture with a low level of oxygen (less than 21% oxygen) and a risk of hypoxemia.
- Oxygen masks are not presently provided with any visual indicator confirming the presence of oxygen flow into the mask, or in the oxygen supply conduit proximate the mask.
- bag valve mask For non-spontaneously breathing patients, one of the most commonly used manual resuscitator gas delivery devices is the bag valve mask or “BVM”.
- BVM bag valve mask
- AMBU automatic resuscitator gas delivery devices
- such devices consist of a flexible air chamber (the “bag”) attached to a face mask or endotracheal tube via a shutter valve.
- the “bag” When the mask is properly applied to a patient (or endotracheal tube is correctly inserted into the patient's trachea) and the “bag” is squeezed, the device forces air into the patient's lungs.
- the BVM When the bag is released, it self-inflates from its supply end, drawing in either ambient air or oxygen supplied by an oxygen supply source, while also allowing the patient's lungs to deflate to the ambient environment (but not to the “bag”) by way of a one-way expired air valve.
- the BVM generally includes two inlet ports for drawing in ambient air or oxygen. When available, oxygen is supplied to one of the inlet ports from a gas supply source, commonly by way of a length of clear plastic conduit.
- the gas supply source may be an in-built hospital supply source, or a gas tank or cylinder.
- the other inlet port can then be used to draw in ambient air, or to connect a reservoir for catching unused oxygen between compressions of the “bag”.
- the reservoir In case oxygen flow is not sufficient to fill the “bag”, the reservoir generally includes a one-way valve for drawing in ambient air to ensure that the BVM continues to supply at least ambient air to the patient.
- BVMs are designed to deliver up to 100% inspired oxygen to a patient. With a loss of supplemental oxygen supply into the “bag”, the BVM will continue to entrain ambient air (with an oxygen concentration of about 21%) with which to ventilate the patient.
- ambient air with an oxygen concentration of about 21%) with which to ventilate the patient.
- any loss of supplemental oxygen supply can have catastrophic sequelae if undiagnosed.
- loss of oxygen supply to a BVM can be, and often is, missed as there is presently no visual flow indicator device provided at or proximate the BVM confirming supplemental oxygen inflow. Again, although the presence of a sound may indicate that gas is flowing, the medical practitioner still has no way of knowing whether the required flow rate of oxygen is present at the BVM.
- gas tanks or cylinders are used to supply oxygen to masks or BVM's, most commonly in emergency, perioperative, critical care or transport scenarios. While some cylinders do have ball-type flow indicators at their supply outlets, the cylinders are often placed in positions in which they are visually obscured, such as under a patient's bed or transportation trolley, or placed side-ways rendering the ball-type flow indicators inaccurate. Additionally, most cylinders do not have alarms in the event of cylinder oxygen supply running empty during use to indicate oxygen supply failure. Even more concerning is that newer designs of oxygen cylinders commonly no longer have ball-type or other flow indicator incorporated into their design. Hence, failure of supply of supplemental gas to gas delivery devices or systems is a real and likely problem.
- the gas flow indicator device of those Applications comprises a gas flow chamber including a transparent portion and an opaque portion, an inlet port, an outlet port, and a gas flow signal means movably disposed within the gas flow chamber; wherein, when there is no gas flow or less than a predetermined gas flow rate, the gas flow signal means is disposed at least substantially within one of the transparent portion and the opaque portion; and wherein, when there is gas flow and the predetermined gas flow rate has been achieved or is being maintained, the gas flow signal means is moved to be disposed at least substantially within the other of the transparent portion and the opaque portion.
- the gas flow signal means is biased to a rest position substantially within the one of the transparent and opaque portions and includes a bellows device or a piston device.
- gas flow indicator device of our earlier patent Applications identified above, works effectively and is reliable, it is relatively complex and requires careful attention to detail in its manufacture.
- the present invention is concerned with providing an improved form of gas flow indicator device.
- a gas flow indicator device including an elongate housing that has a peripheral sidewall that extends between first and second opposite ends and that defines a gas flow chamber through which gas is able to flow from an inlet port at the first end to an outlet port at the second end.
- the device has a gas flow indicator member that extends from adjacent to the first end of the housing over part of the length of the chamber towards the second end.
- the indicator member is of annular form such that gas flowing through the chamber from the inlet port to the outlet port enters the chamber along a bore that extends through the indicator member.
- the indicator member is spaced from an inner surface of the sidewall of the housing to define, with that inner surface, an annular space that forms part of the chamber.
- the device further includes a concealment member that is movable from the first end of the housing in response to a sufficient pressure generated by gas flow from the inlet port to the outlet port, against the action of a biasing member acting to bias the concealment member to the first end.
- the concealment member has an annular peripheral skirt that, under the bias of the biasing member on the concealment member, is receivable into the annular space, such that one of opposite ends of the skirt is able to seal against an annular surface of the housing at or adjacent to an end wall of the housing at the first end of the housing.
- the concealment member also includes, at the other of the opposite ends of the skirt, a transverse wall that defines an opening through which the flow of gas from the inlet port to the outlet port is able to pass, with the opening providing resistance to such flow.
- the arrangement is such that the one of opposite ends of the skirt is able to be held in sealing engagement with the annular surface at or adjacent to the end wall of the housing whereby the indicator member is concealed from view, through a laterally adjacent viewing window portion of the housing when there is no gas flow or a gas flow rate generating less than the sufficient pressure but such that, with increasing gas flow rate the sufficient pressure is achieved and the bias of the biasing member is thereby overcome to enable the concealment member to move towards the second end of the housing and expose the indicator member to view through the viewing window portion of the housing and provide a visual indication indicative of gas flow.
- the movement of the concealment member to expose the indicator member moves the one of opposite ends of the skirt of the concealment member from the annular surface at or adjacent to the end wall of the housing, and most preferably thereby enables a secondary gas flow to the outlet that passes around the one of opposite ends of the skirt between the concealment member and the housing.
- Substantial or full exposure of the indicator member preferably shows that not only is gas flowing, but also that a desired or minimum flow rate, such as 6 L/min, has been achieved and is being maintained. The arrangement enables such satisfactory operation to be seen, such as with only a quick glance being all that is required to obtain confirmation of the correct or required operation.
- the arrangement is such that the device is readily able to function as if in the nature of an “on” or “off” switch, indicating respectively the there is, or there is not, gas being supplied to a patient (preferably at a desired or minimum flow rate, e.g. such as about 6 L/min).
- the concealment member is made of an opaque material through which the indicator member is not able to be seen when the one end of the skirt of the concealment member is held in sealing engagement with the annular surface at or adjacent to the end wall of the housing.
- the outer surface characteristics of the indicator member are able to be seen by being directly viewed and, as detailed herein, those characteristics preferably are such as to highlight exposure of the indicator member after movement of the concealment member.
- the concealment member need not be opaque in order to make possible its concealment or exposure of the indicator member.
- the concealment member may be semi-opaque, translucent or even transparent but of a material of a colour that interacts with the colour of the indicator member in a visually distinctive manner resulting in an observer being able to readily distinguish between a condition in which the actual colour of the indicator member is concealed, or only visible through the concealment member and seen as if of a colour other than its actual colour, and a condition in which the actual colour of the indicator member can be seen by direct viewing made possible by the concealment member being withdrawn or retracted by a sufficient gas flow rate moving the concealment member against the action of the bias member.
- the biasing member may act in compression or in tension in biasing the concealment member to the first end of the housing.
- the biasing member may be compressed between, such as compressed by, the concealment member and the second end and provide the required bias in seeking to expand.
- the biasing member may be within the concealment member, and tensioned by being expanded between, such as by being connected in relation to, each of the transverse wall of the concealment member and the first end of the housing so as to provide the bias in seeking to contract.
- the biasing member preferably comprises a coil spring in each of those alternatives.
- biasing member is a coil spring acting between the concealment member and the second end of the housing
- compression of the spring can limit the extent to which the concealment member can move towards the second end of the housing simply as a consequence of the presence of the compressed spring.
- the biasing member is a coil spring within the concealment member
- the arrangement may be such that the concealment member is able to move so as to contact the end wall at the second end of the housing, although the arrangement may be such that contact of the concealment member with the second end of the housing is precluded by the spring reaching its elastic limit.
- the concealment member preferably is able to move, between a first position in which the indicator member is concealed and a second position in which the indicator member is sufficiently exposed, or fully or substantially fully exposed, over a distance enabling a clear visual indication of gas flow through the device.
- the arrangement is such that, when so exposed, the indicator member can readily be seen through the viewing window portion of the sidewall of the housing by a person in close proximity, such as beside the bed of a patient being supplied oxygen through the device, and preferably also from a considerable distance such as from five to ten meters, or further, from the device.
- the viewing window portion is at least translucent. However, the window portion preferably is sufficiently transparent to facilitate viewing of the indicator member, when exposed.
- the viewing window portion most preferably is of high transparency. Also, the viewing window portion most preferably extends around the full circumferential extent of the sidewall of the housing adjacent to the first end, although it could comprise two or more regions spaced circumferentially around that sidewall of the housing adjacent to the first end. Particularly where the viewing window portion extends around the full circumferential extent of the sidewall of the housing, it preferably is of a high-transparency plastics or glass material, with the material preferably also having a high level of clarity.
- the laterally adjacent portion of the housing may be of a different material to that of a remaining extent of the length of the housing and, in that case, the material of which the remainder of the housing is made may be transparent, translucent or opaque, as required.
- the housing preferably is of unitary or integral form and made of a single material, preferable a rigid plastics material such as a suitable engineering plastics material.
- the remainder of the housing may be rendered opaque by provision of an external or internal lining or coating of an opaque material.
- the housing may be of circular in cross-sections perpendicular to the direction of spacing between the first and second ends.
- the inner surface of the sidewall of the housing may be substantially cylindrical and of substantially constant circular transverse cross-section between the first and second ends, while the sidewall also may have an outer surface that is substantially cylindrical and of substantially constant circular cross-section.
- the outer surface of the sidewall may depart from such cylindrical form, at least along an initial section of its longitudinal extent from adjacent to the first end, with that initial section extending around the gas flow indicator member.
- the outer surface of the sidewall may smoothly increase in diameter to a maximum in a direction away from the first end towards the second end, and thereafter transition to smoothly decrease in diameter substantially to the diameter at the first end, so as to have a convex longitudinal form.
- the at least one viewing window portion discussed above preferably has such convex longitudinal form, with the portion of that form most preferably being circumferentially continuous around the housing.
- the inlet port may be defined by a spigot that projects from the first end of the housing in a direction away from the second end, and that enables connection of a gas supply conduit to the housing.
- the spigot may have an extension into the interior of the housing to provide a tubular extension or hub on or around which the gas flow indicator member can be mounted.
- the indicator member may have an axial extent that is substantially the same as, or slightly greater than, the length of the hub.
- the indicator member may be a firm friction fit on the hub so as to secure the indicator member in position and, to assist in attaining a firm fit, the indicator member and the hub may have complementary surfaces by which they are mutually engaged.
- the surfaces may taper so as to decrease in cross-section towards the outlet end, for example frustoconically.
- the taper preferably is relatively slight, such as with a half-cone angle of about two to about six degrees.
- the indicator member may be bonded or welded onto the hub, without the need for a friction fit.
- the indicator member may have an end, adjacent to the end wall at the first end of the housing, by which the indicator member is bonded or welded to the end wall.
- the indicator member may have, at its end remote from the first end of the housing, a flange that overlaps the corresponding end of the hub, with the flange bonded or welded to that end of the hub.
- the spigot does not have an extension that projects into the housing, with the indicator member being bonded or welded to the end wall of the housing at the first end, or mechanically engaged with that end wall such as by screw-threaded engagement or a snap fit in or around the inlet port.
- the skirt of the concealment member preferably has an outer surface that is spaced from the inner surface of the sidewall of the housing, although relative sliding contact may be provided between those surfaces. Where there is spacing between the surfaces, this most preferably applies throughout the extent of movement of the concealment member longitudinally within the housing.
- the inner surface of the sidewall of the housing preferably is of substantially uniform circular cross-section.
- the device may have guide members that maintain the concealment member in a substantially co-axial relationship with the housing. Such guide members may comprise a plurality of circumferentially spaced projections that stand proud, or project inwardly, of the inner surface of the housing so as to be contactable with the outer surface of the skirt of the concealment member.
- the guide members are provided by a plurality of longitudinal ribs on the inner surface of the sidewall of the housing, with three or four such ribs usually being sufficient.
- the plurality of guide members may stand proud, or project outwardly, of the outer surface of the skirt of the concealment member.
- the outer surface of the skirt of the concealment member may be of substantially uniform circular cross-section, although it preferably has a slight taper so as to decrease in cross-section towards the other end at which the transverse wall of the concealment member is provided, such as a taper providing a half-cone angle of from about two to about six degrees.
- the guide members not only centralise the concealment member, but also preferably obviate noise or vibrations due the concealment member rattling or oscillating laterally within the housing.
- the inner surface of the skirt of the concealment member, when the indicator member is concealed, preferably is spaced from the outer peripheral surface of the indicator member. This avoids contact between the skirt of the concealment member and the indicator member, and thereby obviates friction that could resist movement of the concealment member relative to the indicator member.
- the skirt of the concealment member and the indicator member each may be of uniform wall thickness along its respective axial extent, while they may be of similar or substantially the same wall thickness.
- the housing may have an end wall that defines the outlet port.
- the end wall preferably is separable from the sidewall of the housing.
- the end wall comprises an annular peripheral rim that is engaged with the sidewall of the housing around the second end, a central hub portion and a plurality of circumferentially spaced connectors that extend between the rim and the hub.
- a gas delivery device, gas delivery system or gas supply conduit including the gas flow indicator device of any one of the preceding paragraphs.
- FIG. 1 is a schematic representation of gas flow indicator device according to the invention as incorporated into a face mask installed on a patient to receive a controlled gas supply;
- FIG. 2 shows a perspective view of a first preferred embodiment of a gas flow indicator device according to the invention, shown in an operating condition;
- FIG. 3 is an exploded view of the device of FIG. 2 , shown in a non-operating condition in relation to a face mask;
- FIG. 4 is perspective view from one end of the device of FIG. 2 , this time shown in a non-operating condition;
- FIG. 5 is similar to FIG. 4 but taken from the other end;
- FIG. 6 is a side elevation showing the device of FIG. 2 in the non-operating condition applicable to each of FIGS. 4 and 5 ;
- FIG. 7 corresponds to FIG. 6 , but shows the device in its operating condition
- FIGS. 8 and 9 correspond to views FIGS. 4 and 5 , respectively, but in exploded views on an enlarged scale;
- FIG. 10 is a plan view from one end of the device of FIG. 2 ;
- FIG. 11 is a sectional view of the device of FIG. 2 , taken on line X-X of FIG. 10 ;
- FIG. 12 corresponds to FIG. 10 , but is taken from the opposite end;
- FIG. 13 is a schematic representation of the device of FIG. 2 , illustrated in operation in accordance with the condition shown in FIG. 7 ;
- FIGS. 14 and 15 correspond to FIGS. 6 and 7 , respectively, but with one component sectioned to better illustrate internal components;
- FIGS. 16 to 18 show different preferred forms for one component of the device of FIG. 2 ;
- FIG. 19 shows the device of FIG. 2 , in a view corresponding to FIG. 6 , as incorporated into a conduit flow-line;
- FIG. 20 corresponds to FIG. 19 , but shows the device and flow-line in longitudinal section
- FIGS. 21 to 24 illustrate gas flow indicator device according to a second embodiment of the invention, shown in views corresponding to FIGS. 6, 11, 13 and 10 , with FIGS. 22 and 23 taken on line Y-Y of FIG. 24 ;
- FIGS. 25 to 28 show an end elevation, a side elevation, a perspective view and a section view taken on line Z-Z of FIG. 26 , respectively of a component suitable in the device of FIGS. 2 to 20 , or the device of FIGS. 21 to 24 ;
- FIGS. 29 to 36 provide respective sectional views illustrating alternatives for securing together two components for the device of the illustrated first or second embodiments of the invention shown in FIGS. 2 to 20 and FIGS. 21 to 24 respectively;
- FIG. 37 is similar to FIG. 15 , but highlights an encircled region of the device
- FIG. 38 illustrates performance with the encircled region of FIG. 37 ;
- FIGS. 39 to 42 illustrate different detail for components of the device of FIG. 2 , but also applicable to the device of FIGS. 21 to 24 .
- FIG. 1 schematically illustrates a patient P undergoing a procedure in which the patient P is receiving a controlled supply of required gas through a device 10 according to the invention.
- the device 10 is fitted into a face mask F held by strap S over the nose and mouth of the patient P and the required gas is passed to the device 10 from a source of supply (not shown) via a conduit C.
- the device 10 comprises a gas flow indicator device that, as shown in FIGS. 2 to 15 , is of elongate form.
- Device 10 includes an elongate housing 12 that, as shown in FIG. 3 , has a peripheral sidewall 14 that extends between first and second opposite ends comprising an inlet end 16 and an outlet end 18 , respectively.
- the housing 12 defines a gas flow chamber 20 through which gas is able to flow from an inlet port 22 at the inlet end 16 to an outlet port 24 (see, for example, FIG. 4 ) at the outlet end 18 .
- the device 10 has a gas flow indicator member 26 that extends from adjacent to the inlet end 16 of the housing 12 over part of the length of the chamber 20 towards the outlet end 18 , typically less than half the length of the chamber 20 , such as from 35 to 45% of the length.
- the indicator member 26 is of annular form such that gas flowing through the chamber 20 from the inlet port 22 to the outlet port 24 enters the chamber 20 along a bore 28 that extends through the indicator member 26 .
- the indicator member 26 is spaced from an inner surface 30 (see, for example, FIG. 7 ) of the sidewall 14 of the housing 12 to define, with that inner surface 30 , an annular space 32 (again, see for example, FIG. 7 ) that forms part of the chamber 20 .
- the device 10 has a concealment member 34 that is movable from the inlet end 16 of the housing 12 in response to a sufficient pressure generated by gas flow from the inlet port 22 to the outlet port 24 .
- a biasing member 36 acting to bias the concealment member 34 to the first end 16 of housing 12 .
- the concealment member 34 has an annular peripheral skirt 38 that is receivable into the annular space 32 , such that one end 40 of the skirt 38 is able to seal against an annular abutment surface 42 defined by housing 12 at or adjacent to an end wall 44 of the housing 12 at the inlet end 16 of the housing 12 .
- the concealment member 34 also includes, at the other end 46 of the skirt 38 , a transverse wall 48 that defines an opening 50 through which the flow of gas from the inlet port 22 to the outlet port 24 is able to pass, with the opening 50 providing resistance to such flow.
- the arrangement is such that the end 40 of the skirt 38 is able to be held in sealing engagement with the annular abutment surface 42 of the housing 12 whereby the indicator member 26 is concealed from view, through a laterally adjacent viewing window portion 52 of the housing 12 that is at least translucent until, with increasing gas flow rate, the sufficient pressure is achieved and the bias of the biasing member 36 is thereby overcome to enable the concealment member 34 to move towards the outlet end 18 of the housing 12 and expose the indicator member 26 to view through the viewing window portion 52 of the housing 12 and provide a visual indication indicative of gas flow.
- the indicator member 26 shows that not only is gas flowing, but also that a desired or minimum predetermined flow rate, such as a flow rate of about 6 L/min, has been achieved and is being maintained.
- the movement of the concealment member 34 to expose the indicator member 26 moves the end 40 of the skirt 38 of the concealment member 34 from the annular abutment surface 42 of the housing 12 , and most preferably thereby enables a secondary gas flow to the outlet port 24 that passes around the end 40 of the skirt 38 between the concealment member 34 and the housing 12 (as will be described in further detail below, with reference to FIG. 13 ).
- the biasing member 36 is a coil spring that acts in compression in acting to bias the concealment member 34 to the inlet end 16 of the housing 12 .
- the preferred coil spring biasing member 36 may be compressed by and between the concealment member 34 and the outlet end 18 of the housing 12 so as to provide the required bias in seeking to expand.
- the concealment member 34 is able to move against the bias from the position shown FIGS. 4 to 6 , in which the indicator member 26 is concealed, to the position shown in FIGS.
- the arrangement is such that, when exposed, the indicator member 26 can readily be seen through the laterally adjacent viewing window portion 52 of the sidewall 14 of the housing 12 by a person in close proximity, such as beside the bed of patient P of FIG. 1 , and preferably also from a considerable distance such as from five to ten meters, or further, from the device 10 provided for patient P.
- the arrangement of device 10 is such that its operating condition can be readily determined, such as with only a quick glance being all that is required to obtain confirmation of the operation condition.
- the arrangement is such that device 10 is readily able to function, in effect, as if in the nature of an “on” or “off” switch, indicating respectively the there is, or there is not, gas being supplied to a patient P (preferably at a desired or minimum flow rate, e.g. such as about 6 L/min).
- the viewing window portion 52 is at least translucent, it preferably is transparent to facilitate viewing of the indicator member 26 , when exposed.
- the viewing window portion 52 most preferably is of high transparency, and most preferably extends around the full circumferential extent of the sidewall 14 of the housing 12 adjacent to the first end 16 , as shown in each of FIGS. 2 to 15 .
- window portion could comprise two or more regions spaced circumferentially around sidewall 14 .
- the viewing window portion 52 extends around the full circumferential extent of the sidewall 14 , it preferably is of a high-transparency plastics or glass material, with the material preferably also having a high level of clarity.
- the laterally adjacent viewing window portion 52 may be of a different material to that of a remaining extent of the length of the housing 12 and, in that case the material of which the remainder of the housing 12 is made may be transparent, translucent or opaque, as required.
- the housing 12 preferably is of unitary or integral form and made of a single material, preferable a rigid plastics material such as a suitable engineering plastics material.
- the housing 12 is of circular in cross-sections perpendicular to the direction of spacing between the inlet and outlet ends 16 and 18 , of device 10 .
- the inner surface 30 of the sidewall 14 of the housing 12 may be substantially cylindrical and of substantially constant circular transverse cross-section between the first and second ends 16 and 18 , while the sidewall 14 also may have an outer surface that is substantially cylindrical and of substantially constant circular cross-section.
- the outer surface 54 of the sidewall 14 departs from such cylindrical form along an initial section of its longitudinal extent from adjacent to the first end 16 , that substantially corresponds to the viewing window portion 52 .
- the outer surface 54 of the sidewall 14 smoothly increases in diameter to a maximum in a direction away from the inlet end 16 towards the outlet end 18 , and thereafter smoothly decreases in diameter substantially to the diameter at the first end 16 , so as to have a convex longitudinal form.
- the convex longitudinal form most preferably is circumferentially continuous around the housing 12 .
- the inlet port 22 is defined by a spigot 56 that projects from the inlet end of the housing 12 in a direction away from the outlet end 18 , with the spigot 56 enabling connection of device 10 to a gas supply conduit C.
- the spigot 56 has an extension that projects into the interior of the housing 12 to provide a tubular hub 58 on or around which the gas flow indicator member 26 is securely mounted.
- the indicator member 26 has an axial extent that is substantially the same as, or slightly greater than, the length of the hub 58 .
- the indicator member 26 may be a firm friction fit on the hub 58 so as to secure the indicator member 26 in position and, to assist in attaining a firm fit, the indicator member 26 and the hub 58 may have complementary surfaces by which they are mutually engaged.
- the surfaces may taper so as to decrease in cross-section towards the outlet end 18 , for example frustoconically, such as with a half-cone angle of about two to about six degrees.
- the indicator member 26 may be bonded or welded onto the hub 58 , without the need for a friction fit.
- the indicator member 26 may have an end adjacent to the end wall 44 at the inlet end 16 of the housing 12 , by which the indicator member 26 is bonded or welded to the end wall 44 .
- the indicator member 26 may have, at its end remote from the inlet end 16 of the housing 12 , a flange that overlaps the corresponding end of the hub 58 , with the flange bonded or welded to that end of the hub 58 .
- the spigot 56 does not have an extension that projects into the housing, in which case the indicator member 26 may be bonded or welded to the end wall 44 of the housing 12 , or mechanically engaged with that end wall 44 such a by screw-threaded engagement or a snap- fit in or around the inlet port 22 .
- the skirt 38 of the concealment member 34 has an outer surface 60 that is spaced from the inner surface 30 of the sidewall 14 of the housing 12 , although relative sliding contact may be provided between those surfaces. Where there is spacing between the surfaces 30 and 60 , this most preferably applies throughout the extent of movement of the concealment member 34 longitudinally within the housing 12 .
- the inner surface 30 of the sidewall 14 of the housing 12 preferably is of substantially uniform circular cross-section.
- the outer surface 60 of the skirt 38 of the concealment member 34 may be of substantially uniform circular cross-section although, as shown, it preferably has a slight taper so as to decrease in cross-section towards the end at which the transverse wall 48 of the concealment member 34 is provided.
- the slight taper may be such as to provide a half-cone angle of from about two to about six degrees.
- the inner surface of the skirt 38 of the concealment member 34 when the indicator member 26 is concealed, is preferably spaced from the outer peripheral surface 62 of the indicator member 26 . This avoids contact between the skirt 38 of the concealment member 34 and the indicator member 26 , and thereby obviates friction that could resist movement of the concealment member 34 relative to the indicator member 26 .
- the skirt 38 of the concealment member 34 and the indicator member 26 each may be of uniform wall thickness along its respective axial extent, while they may be of similar or substantially the same wall thickness.
- the housing 12 has an end wall 64 that defines the outlet port 24 .
- the end wall 64 preferably is separable from the sidewall 14 of the housing 12 .
- the end wall 64 comprises an annular peripheral rim 66 that is engaged with the sidewall 14 of the housing 12 around the outlet end 18 , a central hub 68 and a plurality of circumferentially spaced connectors 70 that extend between the rim 66 and the hub 68 .
- the coil spring comprising biasing member 36 is positioned co-axially within housing 12 and with respect to transverse wall 48 of concealment member 34 and end wall 64 .
- a respective end of biasing member 36 may be attached to walls 48 and 64 , or the member 36 may simply be held between walls 48 and 64 under compression.
- the arrangement of end wall 64 is such that it forms an end cap for device 10 that not only provides a means of retaining component parts of device 10 within housing 12 , but also acts as a grill that prevents foreign objects from entering into device 10 .
- required gas such as oxygen or oxygen-enriched air is supplied through device 10 .
- the gas is supplied through conduit C so as to flow through spigot 56 and then through inlet port 22 and bore 28 .
- the gas flows into a sub-chamber 72 defined within concealment member 34 , indicator member 26 and end wall 44 of housing 12 , before flowing through opening 50 of transverse wall 48 , of concealment member 34 , to pass into chamber 20 , before exiting through outlet port 22 into facemask F.
- the gas received into mask F then can be inhaled by patient P, and is supplied at a rate appropriate for the patient's P needs.
- the resistance to flow is determined by the size of opening 50 relative to the area of transverse wall 48 , of concealment member 34 , and the compressibility of the spring comprising biasing means 36 .
- Opening 50 is such as to resist gas flow from sub-chamber 72 to chamber 20 , causing a generation of gas pressure against transverse wall 48 that, supplemented by pressure against the tapered inner surface 74 of skirt 38 , acts to oppose the bias of biasing member 36 and tends to move concealment member 34 away from the inlet end 16 of housing 12 , towards the outlet end 18 .
- the resistance to gas flow provided by opening 50 is designed to result in the pressure in sub-chamber 72 increasing to a level at which such movement of concealment member 34 occurs, with consequential breaking of the sealing engagement between the end 40 of skirt 38 of concealment member 34 and the annular abutment surface 42 defined by housing 12 .
- the gas flow through opening 50 is somewhat centralised in a gas stream along an axial line through device 10 , as depicted in FIG. 13 by solid-line arrows A-A.
- a second gas stream commences, with this being radial, outwardly between end 40 and abutment surface 42 , and then as an annular curtain of gas passing to outlet port 24 between the inner surface 30 of sidewall 14 of housing 12 and the outer surface 60 of skirt 38 of concealment member 34 .
- the dotted-line arrows B-B depict the second, annular curtain gas stream.
- This results in a reduction of pressure within concealment member 34 although the reduced pressure against wall 48 is supplemented by gas pressure against the annular area of end 40 of skirt 38 , as well as a reduced pressure prevailing over the tapered outer surface 60 of skirt 38 relative to the pressure over the tapered inner surface 74 of skirt 38 .
- the overall balance achieved with application of a gas supply pressure within a typical range is such that the concealment member 34 is moved against the biasing member 36 a distance exposing a sufficient axial extent of indicator member 26 whereby indicator member 26 is visible through the laterally adjacent viewing window portion 52 of housing 12 .
- the arrangement is such that concealment member 34 typically is moved beyond the position shown in FIG. 13 , such as to a position able to be seen in each of FIGS. 2, 7 and 15 , so that the external surface 62 of indicator member 26 is exposed and able to be viewed through the laterally adjacent window portion 52 of housing 12 .
- the spacing within chamber 20 between the outlet end 18 of housing 12 and the nearer end of indicator member 26 is able to accommodate concealment member 34 and the compressed coils of the spring comprising biasing member 36 .
- the bias provided by biasing member 36 acts to return the concealment member to its position in which it conceals indicator member 26 from view.
- the indicator member 26 preferably is made of or coated with a material that maximises its visibility.
- the material may have a strong, vibrant colour, or it may be iridescent, fluorescent or highly reflective, so as to draw the eye E of a person charged with observing the patient P from time to time to ensure a required supply of gas is being maintained.
- the outer surface 62 of indicator member 26 may be marked, textured or patterned as shown in FIGS. 16 to 18 .
- FIG. 16 shows indicator member 26 as provided graduated markings 78 facilitating fine-tuning and observance of maintenance of the flow of gas through device 10 , such as by appropriate adjustment of a source of gas supply.
- FIG. 16 shows indicator member 26 as provided graduated markings 78 facilitating fine-tuning and observance of maintenance of the flow of gas through device 10 , such as by appropriate adjustment of a source of gas supply.
- FIG. 17 shows an indicator member 26 having an outer surface 62 that is textured to maximize its exposure being observed, even in low lighting conditions.
- FIG. 18 shows an indicator member 26 that is patterned in a checkerboard to provide a plurality of areas differing in colour, texture or both colour and texture.
- FIG. 3 shows an example of a face mask F with which the device 10 is usable.
- the mask F has a main body M, a gas inlet G, ventilation apertures V and, around the edge of body M, openings O by which, as shown in FIG. 1 , the mask F can be retained in position on the face of a patient P by straps S.
- the gas inlet G is of tubular form and the outlet end 18 of device 10 is a neat sliding fit in inlet G.
- the device 10 has a peripheral bead 80 around the exterior of housing 12 that ensures the outlet end 18 of device 10 is not inserted too far into inlet G of face mask F.
- the indicator member 26 first is inserted into the outlet end 18 of housing 12 and fitted onto and secured in relation to the hub 58 provided as an extension of spigot 56 .
- the concealment member 34 then is positioned over indicator member 26 to position the inlet end 40 of skirt 38 of member 34 against the abutment surface 42 .
- the coil spring to comprise biasing member 36 then is positioned within the outlet end 18 of housing 12 and compressed down onto transverse wall 48 of concealment member 34 by application of end wall 64 so as to securely engage the rim 66 of wall 64 onto the outlet end 18 of housing 12 .
- FIGS. 19 and 20 show device 10 in a different arrangement to that of FIG. 1 .
- the device 10 is installed in a conduit line that has an inlet conduit length C 1 connected onto spigot 56 in the manner shown for conduit C of FIG. 1 .
- member 10 is provided with an outlet end wall 64 that has an integral spigot 76 that projects axially away from housing 12 .
- the spigot 76 has a second conduit length C 2 connected, with gas passing through device 10 being received into conduit length C 2 by which the gas is passed to a required location.
- the required location maybe, for example, a face mask, bag valve mask or endotracheal tube, etc.
- FIGS. 21 to 24 illustrate an alternative form of device 11 according to the invention.
- the structure of device 11 generally will be understood from the description of device 10 of the preceding Figures, and corresponding components have the same reference numeral, plus 1. Description of FIGS. 21 to 24 therefore will be limited to principle matters of difference between device 10 and device 11 .
- the principle feature of difference resides in the device 11 having a biasing member 37 preferably comprising a coil spring that is located within the concealment member 35 .
- the biasing member 37 is in tension so that the inlet end 41 of skirt 39 of the concealment member 35 is pulled into sealing engagement with an annular abutment surface 43 defined by housing 13 at or adjacent to an end wall 45 of the housing 13 at the inlet end 17 of the housing 13 .
- the biasing member 37 has one of opposite ends engaged with end wall 45 of housing 13 , around the inlet port 23 .
- the other of the opposite ends of the biasing member 37 is secured to an annular boss 77 that is provided on the transverse wall 49 of concealment member 35 , within sub-chamber 73 , and that defines the opening 51 in transverse wall 49 .
- the movement of concealment member 35 to expose the indicator member 27 increases tension in the biasing means 37 . Termination or interruption of gas flow through device 11 thus results the bias provided by member 37 returning concealment member 35 to its position in which it conceals indicator member 27 and prevents member 27 from being viewed through window portion 53 of housing 13 .
- FIGS. 25 to 28 show a housing 12 suitable for the device 10 shown in FIGS. 2 to 20 , but with a modification that also can be adopted in the housing 13 of the device 11 of FIGS. 21 to 24 .
- the modification is in the provision, along the inner surface 30 of the sidewall 14 of housing 12 , of a number of longitudinally extending, circumferentially spaced ribs 82 . In the arrangement shown, there are four ribs 82 , although there may only be three (or less) or there may be more than four ribs 82 .
- the ribs 82 preferably are uniformly spaced from each other around inner surface 30 of housing 12 , while the cross section of each rib 82 is such that it substantially bridges the spacing between the inner surface 30 of housing 12 and the outer surface 60 of skirt 38 of concealment member 34 without impeding movement of the concealment member 34 with or against the bias of the biasing member 36 .
- the ribs 82 do serve to centralize the concealment member 34 during such movement and when stationary. Ribs 82 also serve to obviate noise or vibrations due to the concealment member 34 rattling or oscillating laterally within housing 12 during use of device 10 .
- ribs 82 are illustrated in FIGS. 25 to 28
- other alternative centralizing formations could be provided.
- inner surface 30 of sidewall 14 of housing 12 could have formed thereon a plurality of small protrusions that are spaced over, both along and around, the inner surface 30 .
- the centralizing and/or noise reduction formations, such as ribs or protrusions could be provided over the outer surface 60 of skirt 38 of concealment member 34 , rather than over inner surface 30 of the sidewall 14 of housing 12 .
- FIGS. 29 to 32 illustrate alternative construction detail by which indicator member 26 may be secured concentrically on the hub 58 comprising a continuation of spigot 56 of device 10 of FIGS. 2 to 20 .
- the same alternatives apply to the securement of the indicator member 27 on the hub 59 in the device 11 of FIGS. 21 to 24 .
- the indicator member 26 is a neat fit on hub 58 , such as to provide a strong friction fit or with securement enhanced by a film providing adhesive bonding.
- FIG. 30 shows an arrangement in which indicator member 26 is spaced slightly from hub 58 but is secured by an adhesive bonding layer 84 between the opposed surfaces of member 26 and hub 58 .
- a fusible fin 86 is provided around the end of indicator member 26 opposed to end wall 44 of housing 12 and, when the fin 86 is heated by any suitable arrangement, the fin 86 melts to bond that end of member 26 to wall 44 .
- FIGS. 33 and 35 Further alternatives for securing indicator member 26 on hub 58 of device 10 , with similar possible for securing member 27 on hub 59 of device 11 , are shown in FIGS. 33 and 35 , with FIGS. 34 and 36 providing respective enlarge detail.
- the indicator member 26 is shown as having an in-turned flange 88 around the end of member 26 remote from end wall 44 of housing 12 .
- the flange 88 overlaps the adjacent end of hub 58 , with a fin 90 on flange 88 bearing against that adjacent end of hub 58 .
- Heating of the fin 90 by any suitable arrangement enables the fin 90 to melt, with indicator member 26 then able to move more firmly onto hub 58 and be secured by flange 88 being fusion bonded to the adjacent end of hub 58 .
- a mechanical securement of indicator member 26 onto hub 58 the end of indicator member 26 opposed to end wall 44 of housing 12 has an array of circumferentially spaced, axially projecting hooked fingers 92 .
- each finger 92 is forced to elastically flex so as to enter a respective aligned opening 94 through end wall 44 of housing 12 .
- each finger 92 is able to elastically recover, to locate its out-turned end against the outer surface of end wall 44 and thereby lock indicator member 26 on hub 58 .
- FIG. 37 and, in particular, the enlarged detail of FIG. 38 elaborates on the description above in relation to the viewing window portion 52 of the housing 12 of device 10 shown in FIGS. 2 to 20 , with the same being applicable to the corresponding features of device 11 of FIGS. 21 to 24 .
- the longitudinally arcuate form of the outer surface 54 of housing 12 within the window portion 52 enables window portion 52 to function as a magnifying lens. The effect is such that light rays R shown as issuing out from indicator member 26 diverge out from window portion 52 .
- the lens effect is such as to permit viewing of indicator member 26 from a considerable distance, as indicator member 26 is seen as enlarged relative to its actual size and also to be viewed over a wider viewing angle.
- FIGS. 39 to 42 illustrate further variants possible to assist with recognition of the operating condition of device 10 of FIGS. 2 to 20 , with the same being applicable to device 11 of FIGS. 21 to 24 .
- FIGS. 39 and 41 show the same condition for device 10 , with the indicator member (not visible) concealed by the concealment member 34 , although FIG. 41 shows internal structure consistent with this.
- FIGS. 40 and 42 also are the same condition for device 10 , but with the indicator member 26 exposed as a consequence of movement of the concealment member 34 in response to a required gas flow, although FIG. 42 shows internal structure consistent with this.
- 39 to 42 is the provision of patterning, colouring and texture differences adopted for the external surface 60 of the skirt 38 of concealment member 34 , relative to the outer surface 62 of the indicator member 26 .
- the contrast between surfaces 60 and 62 is such that a viewer is even more readily to distinguish the surface 60 , seen through the window portion 52 when concealment member 34 is concealing the indicator member 26 , from the surface 62 seen when indicator member 26 is exposed by movement of concealment member 34 as a consequence of a required flow of gas through device 10 .
- the length of the housing 12 between the transparent window portion 52 and the second end 18 may be opaque (or coated with an opaque material or coating, etc.) and of any suitable colour, thereby serving to maximise the visual contrast between the respective conditions in which the indicator member 26 is concealed or exposed. Also, where device 10 is to be one of a series as discussed later herein, that opaque length of the housing 12 may carry indicia that distinguishes that device 10 from others of the series.
- the opening may be in the end wall 44 or 45 , such as shown by hole 96 in device 10 of FIGS. 3, 8 and 9 .
- the, or each, opening may be in the side wall 14 or 15 of respective device 10 or 11 , closely adjacent to the end wall 44 or 45 .
- the opening or openings is/are in end wall 44 or 45
- its/their position is such that it/they is/are fully covered by the nearer end 40 or 41 of skirt 38 or 39 of the concealment member 34 or 35 when that end 40 or 41 of the skirt 38 or 39 is in sealing engagement with the end wall 44 or 45 .
- ambient air is precluded from being drawn into the chamber 20 or 21 , through the opening or openings, until the seal between end 40 or 41 of skirt 38 or 39 , of concealment member 34 or 35 , is broken by the flow rate of the supply gas increasing to generate the sufficient pressure to cause the concealment member 34 or 35 to move against the action of the biasing member 36 or 37 , to enable the secondary flow of the supplied gas around the exterior of the concealment member 34 or 35 . It is the secondary flow, in passing across the at least one opening that draws in the ambient air, by creating a Venturi effect.
- the gas flow indicator device of the invention enables enhanced ease of observation of a condition, namely exposure of the indicator member, confirming required supply of gas to a patient. With full exposure of the indicator member preferably also confirming that a desired or minimum gas flow rate, such as 6 L/min, has been achieved and is being maintained.
- the device has components that enable low cost production, readily assembled and provide reliable operation. Also, the device is such that it can be provided in a number of alternative forms each suited to providing a respective required gas flow rate. Thus, for a given standardised biasing member, it is possible to vary performance by selecting from a series of devices that differ in the size of the opening of respective concealment members and, hence, the gas flow rate required to move the concealment member to expose the respective indicator member.
- a series of devices may have a standardised such opening in the respective concealment members, but differ in the strength of the biasing action of the respective biasing members.
- a respective gas flow rate is required for each device of the series in order to overcome the resistance to flow provided by the respective opening of the concealment member in order for the concealment member to move against the action of the biasing member.
- the different devices of such series can be readily differentiated by the colour or indicia provided on the outer surface of the skirt of each concealment member, or elsewhere on the device, such as on the housing.
- the device also may be provided in a single standardised form, with the gas flow rate at any time within a suitable range of flow rates being apparent from the extent of exposure of the indicator member.
- All components of the device of the invention are able to be of non-ferrous materials, indeed none of the components need be metallic, making the device suitable for use with a face mask supplying gas to a patient while the patient is undergoing an MRI or other procedure precluding metals.
- the device can be used in any orientation, in contrast for example to apparatus utilising a ball valve type of flow mechanism.
- the construction of the device is such as to enable continuance of gas supply by minimising the risk of the concealment member becoming snagged, while enabling ongoing gas supply even if the concealment member does become snagged.
Abstract
A gas-flow indicator has an elongate housing defining a gas flow chamber between first and second ends, with an annular indicator within the chamber from the first end over part of the length enabling gas to pass along a bore through the indicator. The indicator is spaced from a sidewall of the housing, defining an annular space. A concealment member is movable from the first end by gas flow through the chamber, against a biasing towards the first end and has a skirt receivable into the space to seal at the first end, while the other end of the concealment member defines an opening resisting gas flow. The skirt is hold-able to conceal the indicator at a housing window. Increasing gas flow achieves pressure to overcome the bias, and the concealment member moves towards the second end, exposing the indicator member through the window, to indicate gas flow.
Description
- This application is a continuation application of U.S. Non-Provisional patent application Ser. No. 15/393,404, filed Dec. 29, 2016 and titled “Gas Flow Indicator Device.” The contents of the above-identified Application is relied upon and incorporated herein by reference in its entirety.
- Applicant, VPAS Group Pty Ltd, requests that Letters Patent be granted for Gas Flow Indicator Device as set forth in the following specification:
- The present invention relates generally to gas monitoring device. More particularly, the present invention relates to gas flow indicator device for gas delivery devices or systems and gas supply conduits.
- It will be convenient to hereinafter describe the invention in relation to gas flow indicator device for medical devices, systems or conduits that deliver breathing gas to an individual's airway. However, it is to be appreciated that the present invention is not limited solely to that use. For example, an alternative use for gas flow indicator device of the invention could include breathing gas delivery devices or systems and gas supply conduits for use in the aviation industry. Also, the gas flow indicator device of the invention could be used for other, non-breathing gas applications, and the invention should not be construed as limited to any one or more of the specific examples provided herein.
- Any discussion of documents, devices, acts or knowledge in this specification is included to explain the context of the invention. It should not be taken as an admission that any of the material forms a part of the prior art base or the common general knowledge in the relevant art in Australia, Europe, New Zealand, the United States of America or elsewhere, on or before the priority date of the disclosure herein.
- Unless stated otherwise, throughout the ensuing description, “gas” or “gases” refers to any suitable gas, mixture of gases, vapour or a gas/vapour mixture that, as such, can be monitored using the gas flow indicator device of the invention. A gas with which the flow indicator device can be used can entrain an aerosol. In the context of medical or other respiratory applications of the gas flow indicator device, “gas” refers to any suitable breathing gas, generally oxygen, a mixture of oxygen and inert gas and/or pharmacological agent, air and oxygen-enriched air. Similarly, the expression “gas delivery device”, “gas delivery system” or “gas delivery conduit” refers to any suitable device, system and conduit for supplying gas to, or at, a desired location such as, in the context of a medical or other respiratory application, to or into an individual's airway. Examples of suitable device, devices, system or conduit include, but are not limited to face masks, mouth pieces, nasal cannulas and gas supply conduits. For non-spontaneous breathing applications suitable device, devices, systems and conduits may include manual resuscitator devices, such as, for example, bag valve masks and endotracheal tubes.
- Supplemental gas is widely used in the medical field. For example, supplemental oxygen is used to assist or maintain safe blood oxygen levels for a patient. The duration of supply of supplemental oxygen varies, depending on the condition of the patient and/or the particular circumstance necessitating supplemental oxygen being administered. Common scenarios include patients having a cardiorespiratory disease or dysfunction and surgical/anaesthetic intervention that mandates supplementation of atmospheric air with higher concentrations of inspired oxygen in order to achieve normal oxygen tensions in the patient's blood. Failure to deliver supplemental oxygen can lead to risk of reduced arterial oxygen tension that, if not corrected, can contribute directly to increased morbidity and mortality.
- Failure of supplemental gas delivery is an acknowledged and feared system risk in hospitals. To safeguard against this, more often than not there are multilevel complex alarms and flow sensors within the hospital's in-built gas piping circuitry, and/or at gas supply outlets provided throughout hospital facilities. In addition, anaesthetic machines, intensive care ventilators, or the likes, have mandatory flow sensors engineered into their design to detect and alert of gas supply failure.
- The gas supply systems of most hospitals generally are monitored, from the source to the supply outlet. The same applies to complex anaesthetic machines and ventilators. However, the most commonly used, and often most simple, gas delivery devices, systems and conduits, are not provided with any effective gas flow indicator device. Hence, their use can lead to the failure of gas delivery going unnoticed. This risk is increased in situations involving gas supply from portable gas tanks or cylinders.
- One of the most commonly used gas delivery devices for spontaneously breathing patients is the gas delivery mask, or oxygen mask. Sometimes called the “Hudson Mask”, with reference to the early mask innovations of the Hudson Company, most such masks are made of a clear plastics material and include a body that is sized to seat over the nose and mouth of a patient. With conventional mask designs, gas is introduced through a gas inlet, and expiratory gases are vented from either around the side of the mask or through appropriately placed ventilation apertures. Gas is supplied to the gas inlet from a gas supply source, commonly by way of a length of clear plastic conduit. The gas supply source may be an in-built hospital supply source, or a gas tank or cylinder.
- Oxygen masks usually are designed to increase a patient's inspired fraction of oxygen, such as from about 21% to about 40%. The oxygen flow rate required to achieve this is about 6 litres per minute (“6 L/min”). When oxygen flow into the mask fails the prescribed inspired oxygen concentration is not achieved. Of greater concern, the patient re-breathes their expired gases which can't be replenished satisfactorily by entrainment of air around the side of the mask, ultimately leading to the inspiration of a gas mixture with a low level of oxygen (less than 21% oxygen) and a risk of hypoxemia. Oxygen masks are not presently provided with any visual indicator confirming the presence of oxygen flow into the mask, or in the oxygen supply conduit proximate the mask. With the use of a mask, it is not inherently obvious to a medical practitioner, to a carer or even to the patient when there is an insufficient or complete lack of oxygen flow. A visual inspection of the oxygen delivery system (e.g. conduit and mask) will not generally indicate whether or not oxygen is or flowing. For this reason, medical practitioners often find it necessary to use audible cues as a means of identifying that there is a flow of oxygen. However, even putting ones ear or a stethoscope adjacent to a mask may sometimes still not make clear whether gas is flowing, and the medical practitioner still has no way of knowing whether oxygen is being supplied at the prescribed flow rate of oxygen, such as about 6 L/min.
- For non-spontaneously breathing patients, one of the most commonly used manual resuscitator gas delivery devices is the bag valve mask or “BVM”. Sometimes called the “AMBU” bag or mask, with reference to the proprietary name appointed by the inventors' of the original BVM, such devices consist of a flexible air chamber (the “bag”) attached to a face mask or endotracheal tube via a shutter valve. When the mask is properly applied to a patient (or endotracheal tube is correctly inserted into the patient's trachea) and the “bag” is squeezed, the device forces air into the patient's lungs. When the bag is released, it self-inflates from its supply end, drawing in either ambient air or oxygen supplied by an oxygen supply source, while also allowing the patient's lungs to deflate to the ambient environment (but not to the “bag”) by way of a one-way expired air valve. The BVM generally includes two inlet ports for drawing in ambient air or oxygen. When available, oxygen is supplied to one of the inlet ports from a gas supply source, commonly by way of a length of clear plastic conduit. The gas supply source may be an in-built hospital supply source, or a gas tank or cylinder. The other inlet port can then be used to draw in ambient air, or to connect a reservoir for catching unused oxygen between compressions of the “bag”. In case oxygen flow is not sufficient to fill the “bag”, the reservoir generally includes a one-way valve for drawing in ambient air to ensure that the BVM continues to supply at least ambient air to the patient.
- BVMs are designed to deliver up to 100% inspired oxygen to a patient. With a loss of supplemental oxygen supply into the “bag”, the BVM will continue to entrain ambient air (with an oxygen concentration of about 21%) with which to ventilate the patient. However, patients requiring the use of such manual resuscitator devices often have severely compromised respiratory function, which means that they require much higher inspired oxygen concentrations than that of ambient air. Therefore, any loss of supplemental oxygen supply can have catastrophic sequelae if undiagnosed. As with the case of the common oxygen mask described above, loss of oxygen supply to a BVM can be, and often is, missed as there is presently no visual flow indicator device provided at or proximate the BVM confirming supplemental oxygen inflow. Again, although the presence of a sound may indicate that gas is flowing, the medical practitioner still has no way of knowing whether the required flow rate of oxygen is present at the BVM.
- Often gas tanks or cylinders are used to supply oxygen to masks or BVM's, most commonly in emergency, perioperative, critical care or transport scenarios. While some cylinders do have ball-type flow indicators at their supply outlets, the cylinders are often placed in positions in which they are visually obscured, such as under a patient's bed or transportation trolley, or placed side-ways rendering the ball-type flow indicators inaccurate. Additionally, most cylinders do not have alarms in the event of cylinder oxygen supply running empty during use to indicate oxygen supply failure. Even more concerning is that newer designs of oxygen cylinders commonly no longer have ball-type or other flow indicator incorporated into their design. Hence, failure of supply of supplemental gas to gas delivery devices or systems is a real and likely problem.
- A substantial advance in the art is provided by the gas flow indicator device disclosed in our International Patent Application No.: PCT/AU2013/000884, published under WO 2014/026221 A1 on 20 Feb. 2014, and its counterparts in Australia (Application No.: 2013302298), Europe (Application No.: 13829326.1), New Zealand (Application No.: 705892) and the United States of America (application Ser. No. 14/421,039). The gas flow indicator device of those Applications comprises a gas flow chamber including a transparent portion and an opaque portion, an inlet port, an outlet port, and a gas flow signal means movably disposed within the gas flow chamber; wherein, when there is no gas flow or less than a predetermined gas flow rate, the gas flow signal means is disposed at least substantially within one of the transparent portion and the opaque portion; and wherein, when there is gas flow and the predetermined gas flow rate has been achieved or is being maintained, the gas flow signal means is moved to be disposed at least substantially within the other of the transparent portion and the opaque portion. Typically, the gas flow signal means is biased to a rest position substantially within the one of the transparent and opaque portions and includes a bellows device or a piston device.
- While the gas flow indicator device, of our earlier patent Applications identified above, works effectively and is reliable, it is relatively complex and requires careful attention to detail in its manufacture. The present invention is concerned with providing an improved form of gas flow indicator device.
- According to the present invention, there is provided a gas flow indicator device including an elongate housing that has a peripheral sidewall that extends between first and second opposite ends and that defines a gas flow chamber through which gas is able to flow from an inlet port at the first end to an outlet port at the second end. Within the chamber, the device has a gas flow indicator member that extends from adjacent to the first end of the housing over part of the length of the chamber towards the second end. The indicator member is of annular form such that gas flowing through the chamber from the inlet port to the outlet port enters the chamber along a bore that extends through the indicator member. The indicator member is spaced from an inner surface of the sidewall of the housing to define, with that inner surface, an annular space that forms part of the chamber. The device further includes a concealment member that is movable from the first end of the housing in response to a sufficient pressure generated by gas flow from the inlet port to the outlet port, against the action of a biasing member acting to bias the concealment member to the first end. The concealment member has an annular peripheral skirt that, under the bias of the biasing member on the concealment member, is receivable into the annular space, such that one of opposite ends of the skirt is able to seal against an annular surface of the housing at or adjacent to an end wall of the housing at the first end of the housing. The concealment member also includes, at the other of the opposite ends of the skirt, a transverse wall that defines an opening through which the flow of gas from the inlet port to the outlet port is able to pass, with the opening providing resistance to such flow. The arrangement is such that the one of opposite ends of the skirt is able to be held in sealing engagement with the annular surface at or adjacent to the end wall of the housing whereby the indicator member is concealed from view, through a laterally adjacent viewing window portion of the housing when there is no gas flow or a gas flow rate generating less than the sufficient pressure but such that, with increasing gas flow rate the sufficient pressure is achieved and the bias of the biasing member is thereby overcome to enable the concealment member to move towards the second end of the housing and expose the indicator member to view through the viewing window portion of the housing and provide a visual indication indicative of gas flow. The movement of the concealment member to expose the indicator member moves the one of opposite ends of the skirt of the concealment member from the annular surface at or adjacent to the end wall of the housing, and most preferably thereby enables a secondary gas flow to the outlet that passes around the one of opposite ends of the skirt between the concealment member and the housing. Substantial or full exposure of the indicator member preferably shows that not only is gas flowing, but also that a desired or minimum flow rate, such as 6 L/min, has been achieved and is being maintained. The arrangement enables such satisfactory operation to be seen, such as with only a quick glance being all that is required to obtain confirmation of the correct or required operation. In effect, the arrangement is such that the device is readily able to function as if in the nature of an “on” or “off” switch, indicating respectively the there is, or there is not, gas being supplied to a patient (preferably at a desired or minimum flow rate, e.g. such as about 6 L/min).
- In one convenient arrangement, the concealment member is made of an opaque material through which the indicator member is not able to be seen when the one end of the skirt of the concealment member is held in sealing engagement with the annular surface at or adjacent to the end wall of the housing. When the concealment member is moved to expose the indicator member, the outer surface characteristics of the indicator member are able to be seen by being directly viewed and, as detailed herein, those characteristics preferably are such as to highlight exposure of the indicator member after movement of the concealment member. However, the concealment member need not be opaque in order to make possible its concealment or exposure of the indicator member. Thus, the concealment member may be semi-opaque, translucent or even transparent but of a material of a colour that interacts with the colour of the indicator member in a visually distinctive manner resulting in an observer being able to readily distinguish between a condition in which the actual colour of the indicator member is concealed, or only visible through the concealment member and seen as if of a colour other than its actual colour, and a condition in which the actual colour of the indicator member can be seen by direct viewing made possible by the concealment member being withdrawn or retracted by a sufficient gas flow rate moving the concealment member against the action of the bias member.
- The biasing member may act in compression or in tension in biasing the concealment member to the first end of the housing. Thus, the biasing member may be compressed between, such as compressed by, the concealment member and the second end and provide the required bias in seeking to expand. Alternatively, the biasing member may be within the concealment member, and tensioned by being expanded between, such as by being connected in relation to, each of the transverse wall of the concealment member and the first end of the housing so as to provide the bias in seeking to contract. While other arrangements are possible, the biasing member preferably comprises a coil spring in each of those alternatives.
- Where the biasing member is a coil spring acting between the concealment member and the second end of the housing, compression of the spring can limit the extent to which the concealment member can move towards the second end of the housing simply as a consequence of the presence of the compressed spring. Where the biasing member is a coil spring within the concealment member, the arrangement may be such that the concealment member is able to move so as to contact the end wall at the second end of the housing, although the arrangement may be such that contact of the concealment member with the second end of the housing is precluded by the spring reaching its elastic limit.
- The concealment member preferably is able to move, between a first position in which the indicator member is concealed and a second position in which the indicator member is sufficiently exposed, or fully or substantially fully exposed, over a distance enabling a clear visual indication of gas flow through the device. The arrangement is such that, when so exposed, the indicator member can readily be seen through the viewing window portion of the sidewall of the housing by a person in close proximity, such as beside the bed of a patient being supplied oxygen through the device, and preferably also from a considerable distance such as from five to ten meters, or further, from the device. In order that the indicator member is viewable, the viewing window portion is at least translucent. However, the window portion preferably is sufficiently transparent to facilitate viewing of the indicator member, when exposed. The viewing window portion most preferably is of high transparency. Also, the viewing window portion most preferably extends around the full circumferential extent of the sidewall of the housing adjacent to the first end, although it could comprise two or more regions spaced circumferentially around that sidewall of the housing adjacent to the first end. Particularly where the viewing window portion extends around the full circumferential extent of the sidewall of the housing, it preferably is of a high-transparency plastics or glass material, with the material preferably also having a high level of clarity. The laterally adjacent portion of the housing, particularly where the viewing window portion extends fully around the circumferential extent of the sidewall of the housing, may be of a different material to that of a remaining extent of the length of the housing and, in that case, the material of which the remainder of the housing is made may be transparent, translucent or opaque, as required. However, the housing preferably is of unitary or integral form and made of a single material, preferable a rigid plastics material such as a suitable engineering plastics material. Where the housing is of unitary or integral form, and made of a transparent material, the remainder of the housing may be rendered opaque by provision of an external or internal lining or coating of an opaque material.
- The housing may be of circular in cross-sections perpendicular to the direction of spacing between the first and second ends. The inner surface of the sidewall of the housing may be substantially cylindrical and of substantially constant circular transverse cross-section between the first and second ends, while the sidewall also may have an outer surface that is substantially cylindrical and of substantially constant circular cross-section. However, for reasons explained later herein, the outer surface of the sidewall may depart from such cylindrical form, at least along an initial section of its longitudinal extent from adjacent to the first end, with that initial section extending around the gas flow indicator member. In one convenient arrangement, the outer surface of the sidewall, over that initial section of its longitudinal extent, may smoothly increase in diameter to a maximum in a direction away from the first end towards the second end, and thereafter transition to smoothly decrease in diameter substantially to the diameter at the first end, so as to have a convex longitudinal form. The at least one viewing window portion discussed above preferably has such convex longitudinal form, with the portion of that form most preferably being circumferentially continuous around the housing.
- At the first end of the housing, the inlet port may be defined by a spigot that projects from the first end of the housing in a direction away from the second end, and that enables connection of a gas supply conduit to the housing. In one arrangement, the spigot may have an extension into the interior of the housing to provide a tubular extension or hub on or around which the gas flow indicator member can be mounted. In that case, the indicator member may have an axial extent that is substantially the same as, or slightly greater than, the length of the hub. The indicator member may be a firm friction fit on the hub so as to secure the indicator member in position and, to assist in attaining a firm fit, the indicator member and the hub may have complementary surfaces by which they are mutually engaged. The surfaces may taper so as to decrease in cross-section towards the outlet end, for example frustoconically. The taper preferably is relatively slight, such as with a half-cone angle of about two to about six degrees. However other arrangements are possible. For example, the indicator member may be bonded or welded onto the hub, without the need for a friction fit. Alternatively, the indicator member may have an end, adjacent to the end wall at the first end of the housing, by which the indicator member is bonded or welded to the end wall. In a further alternative, the indicator member may have, at its end remote from the first end of the housing, a flange that overlaps the corresponding end of the hub, with the flange bonded or welded to that end of the hub. However, in another arrangement, the spigot does not have an extension that projects into the housing, with the indicator member being bonded or welded to the end wall of the housing at the first end, or mechanically engaged with that end wall such as by screw-threaded engagement or a snap fit in or around the inlet port.
- The skirt of the concealment member preferably has an outer surface that is spaced from the inner surface of the sidewall of the housing, although relative sliding contact may be provided between those surfaces. Where there is spacing between the surfaces, this most preferably applies throughout the extent of movement of the concealment member longitudinally within the housing. The inner surface of the sidewall of the housing preferably is of substantially uniform circular cross-section. The device may have guide members that maintain the concealment member in a substantially co-axial relationship with the housing. Such guide members may comprise a plurality of circumferentially spaced projections that stand proud, or project inwardly, of the inner surface of the housing so as to be contactable with the outer surface of the skirt of the concealment member. In one convenient form, the guide members are provided by a plurality of longitudinal ribs on the inner surface of the sidewall of the housing, with three or four such ribs usually being sufficient. In an alternative arrangement, the plurality of guide members may stand proud, or project outwardly, of the outer surface of the skirt of the concealment member. In either case, the outer surface of the skirt of the concealment member may be of substantially uniform circular cross-section, although it preferably has a slight taper so as to decrease in cross-section towards the other end at which the transverse wall of the concealment member is provided, such as a taper providing a half-cone angle of from about two to about six degrees. The guide members not only centralise the concealment member, but also preferably obviate noise or vibrations due the concealment member rattling or oscillating laterally within the housing.
- The inner surface of the skirt of the concealment member, when the indicator member is concealed, preferably is spaced from the outer peripheral surface of the indicator member. This avoids contact between the skirt of the concealment member and the indicator member, and thereby obviates friction that could resist movement of the concealment member relative to the indicator member. The skirt of the concealment member and the indicator member each may be of uniform wall thickness along its respective axial extent, while they may be of similar or substantially the same wall thickness.
- At the second end, the housing may have an end wall that defines the outlet port. The end wall preferably is separable from the sidewall of the housing. In one convenient arrangement, the end wall comprises an annular peripheral rim that is engaged with the sidewall of the housing around the second end, a central hub portion and a plurality of circumferentially spaced connectors that extend between the rim and the hub.
- According to a further aspect of the present invention, there is provided a gas delivery device, gas delivery system or gas supply conduit including the gas flow indicator device of any one of the preceding paragraphs.
- These and other essential or preferred features of the present invention will be apparent from the description that now follows.
- In order that the invention may be more clearly understood and put into practical effect there shall now be described in detail preferred constructions of a gas flow indicator device for gas delivery devices or systems and gas supply conduits in accordance with the invention. The ensuing description is given by way of non-limitative examples only and is with reference to the accompanying drawings, wherein:
-
FIG. 1 is a schematic representation of gas flow indicator device according to the invention as incorporated into a face mask installed on a patient to receive a controlled gas supply; -
FIG. 2 shows a perspective view of a first preferred embodiment of a gas flow indicator device according to the invention, shown in an operating condition; -
FIG. 3 is an exploded view of the device ofFIG. 2 , shown in a non-operating condition in relation to a face mask; -
FIG. 4 is perspective view from one end of the device ofFIG. 2 , this time shown in a non-operating condition; -
FIG. 5 is similar toFIG. 4 but taken from the other end; -
FIG. 6 is a side elevation showing the device ofFIG. 2 in the non-operating condition applicable to each ofFIGS. 4 and 5 ; -
FIG. 7 corresponds toFIG. 6 , but shows the device in its operating condition; -
FIGS. 8 and 9 correspond to viewsFIGS. 4 and 5 , respectively, but in exploded views on an enlarged scale; -
FIG. 10 is a plan view from one end of the device ofFIG. 2 ; -
FIG. 11 is a sectional view of the device ofFIG. 2 , taken on line X-X ofFIG. 10 ; -
FIG. 12 corresponds toFIG. 10 , but is taken from the opposite end; -
FIG. 13 is a schematic representation of the device ofFIG. 2 , illustrated in operation in accordance with the condition shown inFIG. 7 ; -
FIGS. 14 and 15 correspond toFIGS. 6 and 7 , respectively, but with one component sectioned to better illustrate internal components; -
FIGS. 16 to 18 show different preferred forms for one component of the device ofFIG. 2 ; -
FIG. 19 shows the device ofFIG. 2 , in a view corresponding toFIG. 6 , as incorporated into a conduit flow-line; -
FIG. 20 corresponds toFIG. 19 , but shows the device and flow-line in longitudinal section; -
FIGS. 21 to 24 illustrate gas flow indicator device according to a second embodiment of the invention, shown in views corresponding toFIGS. 6, 11, 13 and 10 , withFIGS. 22 and 23 taken on line Y-Y ofFIG. 24 ; -
FIGS. 25 to 28 show an end elevation, a side elevation, a perspective view and a section view taken on line Z-Z ofFIG. 26 , respectively of a component suitable in the device ofFIGS. 2 to 20 , or the device ofFIGS. 21 to 24 ; -
FIGS. 29 to 36 provide respective sectional views illustrating alternatives for securing together two components for the device of the illustrated first or second embodiments of the invention shown inFIGS. 2 to 20 andFIGS. 21 to 24 respectively; -
FIG. 37 is similar toFIG. 15 , but highlights an encircled region of the device; -
FIG. 38 illustrates performance with the encircled region ofFIG. 37 ; and, -
FIGS. 39 to 42 illustrate different detail for components of the device ofFIG. 2 , but also applicable to the device ofFIGS. 21 to 24 . - In the following detailed description of the invention, reference is made to the drawings in which like reference numerals refer to like elements throughout, and which are intended to show by way of illustration specific embodiments in which the invention may be practiced. It is to be understood that other embodiments may be utilised and that procedural and/or structural changes may be made without departing from the spirit and scope of the invention.
-
FIG. 1 schematically illustrates a patient P undergoing a procedure in which the patient P is receiving a controlled supply of required gas through adevice 10 according to the invention. Thedevice 10 is fitted into a face mask F held by strap S over the nose and mouth of the patient P and the required gas is passed to thedevice 10 from a source of supply (not shown) via a conduit C. - The
device 10 comprises a gas flow indicator device that, as shown inFIGS. 2 to 15 , is of elongate form.Device 10 includes anelongate housing 12 that, as shown inFIG. 3 , has aperipheral sidewall 14 that extends between first and second opposite ends comprising aninlet end 16 and anoutlet end 18, respectively. Thehousing 12 defines agas flow chamber 20 through which gas is able to flow from aninlet port 22 at theinlet end 16 to an outlet port 24 (see, for example,FIG. 4 ) at theoutlet end 18. Within thechamber 20 thedevice 10 has a gasflow indicator member 26 that extends from adjacent to theinlet end 16 of thehousing 12 over part of the length of thechamber 20 towards theoutlet end 18, typically less than half the length of thechamber 20, such as from 35 to 45% of the length. Theindicator member 26 is of annular form such that gas flowing through thechamber 20 from theinlet port 22 to theoutlet port 24 enters thechamber 20 along abore 28 that extends through theindicator member 26. Theindicator member 26 is spaced from an inner surface 30 (see, for example,FIG. 7 ) of thesidewall 14 of thehousing 12 to define, with thatinner surface 30, an annular space 32 (again, see for example,FIG. 7 ) that forms part of thechamber 20. - The
device 10 has aconcealment member 34 that is movable from theinlet end 16 of thehousing 12 in response to a sufficient pressure generated by gas flow from theinlet port 22 to theoutlet port 24. However, such movement ofconcealment member 34 is against the action of a biasingmember 36 acting to bias theconcealment member 34 to thefirst end 16 ofhousing 12. Theconcealment member 34 has an annularperipheral skirt 38 that is receivable into theannular space 32, such that oneend 40 of theskirt 38 is able to seal against anannular abutment surface 42 defined byhousing 12 at or adjacent to anend wall 44 of thehousing 12 at theinlet end 16 of thehousing 12. Theconcealment member 34 also includes, at theother end 46 of theskirt 38, atransverse wall 48 that defines anopening 50 through which the flow of gas from theinlet port 22 to theoutlet port 24 is able to pass, with theopening 50 providing resistance to such flow. The arrangement is such that theend 40 of theskirt 38 is able to be held in sealing engagement with theannular abutment surface 42 of thehousing 12 whereby theindicator member 26 is concealed from view, through a laterally adjacentviewing window portion 52 of thehousing 12 that is at least translucent until, with increasing gas flow rate, the sufficient pressure is achieved and the bias of the biasingmember 36 is thereby overcome to enable theconcealment member 34 to move towards the outlet end 18 of thehousing 12 and expose theindicator member 26 to view through theviewing window portion 52 of thehousing 12 and provide a visual indication indicative of gas flow. As already outlined above, it is preferred that full exposure of theindicator member 26 shows that not only is gas flowing, but also that a desired or minimum predetermined flow rate, such as a flow rate of about 6 L/min, has been achieved and is being maintained. The movement of theconcealment member 34 to expose theindicator member 26 moves theend 40 of theskirt 38 of theconcealment member 34 from theannular abutment surface 42 of thehousing 12, and most preferably thereby enables a secondary gas flow to theoutlet port 24 that passes around theend 40 of theskirt 38 between theconcealment member 34 and the housing 12 (as will be described in further detail below, with reference toFIG. 13 ). - In the arrangement of
FIGS. 2 to 15 , the biasingmember 36 is a coil spring that acts in compression in acting to bias theconcealment member 34 to theinlet end 16 of thehousing 12. Although the use of coil spring is described, and shown in the drawings, it will be appreciated that any suitable form of biasingmember 36 may be utilised in accordance with the invention. As is shown inFIGS. 2 to 20 , the preferred coilspring biasing member 36 may be compressed by and between theconcealment member 34 and the outlet end 18 of thehousing 12 so as to provide the required bias in seeking to expand. Theconcealment member 34 is able to move against the bias from the position shownFIGS. 4 to 6 , in which theindicator member 26 is concealed, to the position shown inFIGS. 2 and 7 in which theindicator member 26 is sufficiently exposed, over a distance enabling a clear visual indication of gas flow throughviewing window portion 52 of thehousing 12 of thedevice 10. The arrangement is such that, when exposed, theindicator member 26 can readily be seen through the laterally adjacentviewing window portion 52 of thesidewall 14 of thehousing 12 by a person in close proximity, such as beside the bed of patient P ofFIG. 1 , and preferably also from a considerable distance such as from five to ten meters, or further, from thedevice 10 provided for patient P. Thus, the arrangement ofdevice 10 is such that its operating condition can be readily determined, such as with only a quick glance being all that is required to obtain confirmation of the operation condition. The arrangement is such thatdevice 10 is readily able to function, in effect, as if in the nature of an “on” or “off” switch, indicating respectively the there is, or there is not, gas being supplied to a patient P (preferably at a desired or minimum flow rate, e.g. such as about 6 L/min). - While the laterally adjacent
viewing window portion 52 is at least translucent, it preferably is transparent to facilitate viewing of theindicator member 26, when exposed. Theviewing window portion 52 most preferably is of high transparency, and most preferably extends around the full circumferential extent of thesidewall 14 of thehousing 12 adjacent to thefirst end 16, as shown in each ofFIGS. 2 to 15 . However, such window portion could comprise two or more regions spaced circumferentially aroundsidewall 14. Particularly where theviewing window portion 52 extends around the full circumferential extent of thesidewall 14, it preferably is of a high-transparency plastics or glass material, with the material preferably also having a high level of clarity. The laterally adjacentviewing window portion 52, particularly where it extends fully around the circumferential extent of the sidewall of thehousing 12, may be of a different material to that of a remaining extent of the length of thehousing 12 and, in that case the material of which the remainder of thehousing 12 is made may be transparent, translucent or opaque, as required. However, thehousing 12 preferably is of unitary or integral form and made of a single material, preferable a rigid plastics material such as a suitable engineering plastics material. - The
housing 12 is of circular in cross-sections perpendicular to the direction of spacing between the inlet and outlet ends 16 and 18, ofdevice 10. Theinner surface 30 of thesidewall 14 of thehousing 12 may be substantially cylindrical and of substantially constant circular transverse cross-section between the first and second ends 16 and 18, while thesidewall 14 also may have an outer surface that is substantially cylindrical and of substantially constant circular cross-section. However, as shown in each ofFIGS. 2 to 15 , for reasons explained later herein with reference toFIGS. 37 and 38 , theouter surface 54 of thesidewall 14 departs from such cylindrical form along an initial section of its longitudinal extent from adjacent to thefirst end 16, that substantially corresponds to theviewing window portion 52. Over that initial section, theouter surface 54 of thesidewall 14 smoothly increases in diameter to a maximum in a direction away from theinlet end 16 towards theoutlet end 18, and thereafter smoothly decreases in diameter substantially to the diameter at thefirst end 16, so as to have a convex longitudinal form. The convex longitudinal form most preferably is circumferentially continuous around thehousing 12. - The
inlet port 22 is defined by aspigot 56 that projects from the inlet end of thehousing 12 in a direction away from theoutlet end 18, with thespigot 56 enabling connection ofdevice 10 to a gas supply conduit C. Thespigot 56 has an extension that projects into the interior of thehousing 12 to provide atubular hub 58 on or around which the gasflow indicator member 26 is securely mounted. Theindicator member 26 has an axial extent that is substantially the same as, or slightly greater than, the length of thehub 58. Theindicator member 26 may be a firm friction fit on thehub 58 so as to secure theindicator member 26 in position and, to assist in attaining a firm fit, theindicator member 26 and thehub 58 may have complementary surfaces by which they are mutually engaged. The surfaces may taper so as to decrease in cross-section towards theoutlet end 18, for example frustoconically, such as with a half-cone angle of about two to about six degrees. Alternatively, theindicator member 26 may be bonded or welded onto thehub 58, without the need for a friction fit. In a further alternative, theindicator member 26 may have an end adjacent to theend wall 44 at theinlet end 16 of thehousing 12, by which theindicator member 26 is bonded or welded to theend wall 44. In another alternative, theindicator member 26 may have, at its end remote from theinlet end 16 of thehousing 12, a flange that overlaps the corresponding end of thehub 58, with the flange bonded or welded to that end of thehub 58. However, in another arrangement (not shown), thespigot 56 does not have an extension that projects into the housing, in which case theindicator member 26 may be bonded or welded to theend wall 44 of thehousing 12, or mechanically engaged with thatend wall 44 such a by screw-threaded engagement or a snap- fit in or around theinlet port 22. - The
skirt 38 of theconcealment member 34 has anouter surface 60 that is spaced from theinner surface 30 of thesidewall 14 of thehousing 12, although relative sliding contact may be provided between those surfaces. Where there is spacing between thesurfaces concealment member 34 longitudinally within thehousing 12. Theinner surface 30 of thesidewall 14 of thehousing 12 preferably is of substantially uniform circular cross-section. Theouter surface 60 of theskirt 38 of theconcealment member 34 may be of substantially uniform circular cross-section although, as shown, it preferably has a slight taper so as to decrease in cross-section towards the end at which thetransverse wall 48 of theconcealment member 34 is provided. The slight taper may be such as to provide a half-cone angle of from about two to about six degrees. The inner surface of theskirt 38 of theconcealment member 34, when theindicator member 26 is concealed, is preferably spaced from the outerperipheral surface 62 of theindicator member 26. This avoids contact between theskirt 38 of theconcealment member 34 and theindicator member 26, and thereby obviates friction that could resist movement of theconcealment member 34 relative to theindicator member 26. Theskirt 38 of theconcealment member 34 and theindicator member 26 each may be of uniform wall thickness along its respective axial extent, while they may be of similar or substantially the same wall thickness. - At the outlet end 18 of
device 10, thehousing 12 has anend wall 64 that defines theoutlet port 24. Theend wall 64 preferably is separable from thesidewall 14 of thehousing 12. In the arrangement shown inFIGS. 2 to 15 , theend wall 64 comprises an annularperipheral rim 66 that is engaged with thesidewall 14 of thehousing 12 around theoutlet end 18, acentral hub 68 and a plurality of circumferentially spacedconnectors 70 that extend between therim 66 and thehub 68. The coil spring comprising biasingmember 36 is positioned co-axially withinhousing 12 and with respect totransverse wall 48 ofconcealment member 34 andend wall 64. A respective end of biasingmember 36 may be attached towalls member 36 may simply be held betweenwalls end wall 64 is such that it forms an end cap fordevice 10 that not only provides a means of retaining component parts ofdevice 10 withinhousing 12, but also acts as a grill that prevents foreign objects from entering intodevice 10. - In use, required gas such as oxygen or oxygen-enriched air is supplied through
device 10. In the arrangement ofFIG. 1 , for example, the gas is supplied through conduit C so as to flow throughspigot 56 and then throughinlet port 22 and bore 28. Frombore 28, the gas flows into a sub-chamber 72 defined withinconcealment member 34,indicator member 26 andend wall 44 ofhousing 12, before flowing through opening 50 oftransverse wall 48, ofconcealment member 34, to pass intochamber 20, before exiting throughoutlet port 22 into facemask F. The gas received into mask F then can be inhaled by patient P, and is supplied at a rate appropriate for the patient's P needs. Balancing the pressure at which the gas is supplied to conduit C, and the resistance to the flow of gas through conduit C and throughdevice 10, enables compliance with the patient's P needs. Withindevice 10, the resistance to flow is determined by the size of opening 50 relative to the area oftransverse wall 48, ofconcealment member 34, and the compressibility of the spring comprising biasing means 36.Opening 50 is such as to resist gas flow fromsub-chamber 72 tochamber 20, causing a generation of gas pressure againsttransverse wall 48 that, supplemented by pressure against the taperedinner surface 74 ofskirt 38, acts to oppose the bias of biasingmember 36 and tends to moveconcealment member 34 away from theinlet end 16 ofhousing 12, towards theoutlet end 18. The resistance to gas flow provided by opening 50 is designed to result in the pressure insub-chamber 72 increasing to a level at which such movement ofconcealment member 34 occurs, with consequential breaking of the sealing engagement between theend 40 ofskirt 38 ofconcealment member 34 and theannular abutment surface 42 defined byhousing 12. The gas flow throughopening 50 is somewhat centralised in a gas stream along an axial line throughdevice 10, as depicted inFIG. 13 by solid-line arrows A-A. However, with that break in sealing engagement betweenend 40 ofskirt 38 andabutment surface 42, a second gas stream commences, with this being radial, outwardly betweenend 40 andabutment surface 42, and then as an annular curtain of gas passing tooutlet port 24 between theinner surface 30 ofsidewall 14 ofhousing 12 and theouter surface 60 ofskirt 38 ofconcealment member 34. InFIG. 13 , the dotted-line arrows B-B depict the second, annular curtain gas stream. - As illustrated in
FIG. 13 , the pressure of gas within thesub-chamber 72 of theconcealment member 34, againsttransverse wall 48, acts against the bias of biasing means 36 and enables initiation of movement ofconcealment member 34 that permits generation of the second gas stream depicted by arrows B-B. This results in a reduction of pressure withinconcealment member 34, although the reduced pressure againstwall 48 is supplemented by gas pressure against the annular area ofend 40 ofskirt 38, as well as a reduced pressure prevailing over the taperedouter surface 60 ofskirt 38 relative to the pressure over the taperedinner surface 74 ofskirt 38. The overall balance achieved with application of a gas supply pressure within a typical range is such that theconcealment member 34 is moved against the biasing member 36 a distance exposing a sufficient axial extent ofindicator member 26 wherebyindicator member 26 is visible through the laterally adjacentviewing window portion 52 ofhousing 12. The arrangement is such thatconcealment member 34 typically is moved beyond the position shown inFIG. 13 , such as to a position able to be seen in each ofFIGS. 2, 7 and 15 , so that theexternal surface 62 ofindicator member 26 is exposed and able to be viewed through the laterallyadjacent window portion 52 ofhousing 12. For this, the spacing withinchamber 20 between the outlet end 18 ofhousing 12 and the nearer end ofindicator member 26 is able to accommodateconcealment member 34 and the compressed coils of the spring comprising biasingmember 36. However, with termination of or an interruption to gas flow throughdevice 10, the bias provided by biasingmember 36 acts to return the concealment member to its position in which it concealsindicator member 26 from view. - The
indicator member 26 preferably is made of or coated with a material that maximises its visibility. Thus, the material may have a strong, vibrant colour, or it may be iridescent, fluorescent or highly reflective, so as to draw the eye E of a person charged with observing the patient P from time to time to ensure a required supply of gas is being maintained. In addition to such materials and effects, theouter surface 62 ofindicator member 26 may be marked, textured or patterned as shown inFIGS. 16 to 18 . Thus,FIG. 16 shows indicator member 26 as provided graduatedmarkings 78 facilitating fine-tuning and observance of maintenance of the flow of gas throughdevice 10, such as by appropriate adjustment of a source of gas supply.FIG. 17 shows anindicator member 26 having anouter surface 62 that is textured to maximize its exposure being observed, even in low lighting conditions.FIG. 18 shows anindicator member 26 that is patterned in a checkerboard to provide a plurality of areas differing in colour, texture or both colour and texture. - Reverting to
FIG. 3 , which shows an example of a face mask F with which thedevice 10 is usable. The mask F has a main body M, a gas inlet G, ventilation apertures V and, around the edge of body M, openings O by which, as shown inFIG. 1 , the mask F can be retained in position on the face of a patient P by straps S. The gas inlet G is of tubular form and the outlet end 18 ofdevice 10 is a neat sliding fit in inlet G. Thedevice 10 has aperipheral bead 80 around the exterior ofhousing 12 that ensures the outlet end 18 ofdevice 10 is not inserted too far into inlet G of face mask F. - In the form of
device 10 depicted inFIGS. 8, 9, 11 and 13 , ease of assembly ofdevice 10 readily can be appreciated. Theindicator member 26 first is inserted into the outlet end 18 ofhousing 12 and fitted onto and secured in relation to thehub 58 provided as an extension ofspigot 56. Theconcealment member 34 then is positioned overindicator member 26 to position theinlet end 40 ofskirt 38 ofmember 34 against theabutment surface 42. The coil spring to comprise biasingmember 36 then is positioned within the outlet end 18 ofhousing 12 and compressed down ontotransverse wall 48 ofconcealment member 34 by application ofend wall 64 so as to securely engage therim 66 ofwall 64 onto the outlet end 18 ofhousing 12. -
FIGS. 19 and 20 show device 10 in a different arrangement to that ofFIG. 1 . InFIGS. 19 and 20 , thedevice 10 is installed in a conduit line that has an inlet conduit length C1 connected ontospigot 56 in the manner shown for conduit C ofFIG. 1 . However,member 10 is provided with anoutlet end wall 64 that has anintegral spigot 76 that projects axially away fromhousing 12. Thespigot 76 has a second conduit length C2 connected, with gas passing throughdevice 10 being received into conduit length C2 by which the gas is passed to a required location. The required location maybe, for example, a face mask, bag valve mask or endotracheal tube, etc. -
FIGS. 21 to 24 illustrate an alternative form ofdevice 11 according to the invention. The structure ofdevice 11 generally will be understood from the description ofdevice 10 of the preceding Figures, and corresponding components have the same reference numeral, plus 1. Description ofFIGS. 21 to 24 therefore will be limited to principle matters of difference betweendevice 10 anddevice 11. The principle feature of difference resides in thedevice 11 having a biasingmember 37 preferably comprising a coil spring that is located within theconcealment member 35. The biasingmember 37 is in tension so that theinlet end 41 ofskirt 39 of theconcealment member 35 is pulled into sealing engagement with anannular abutment surface 43 defined byhousing 13 at or adjacent to anend wall 45 of thehousing 13 at theinlet end 17 of thehousing 13. The biasingmember 37 has one of opposite ends engaged withend wall 45 ofhousing 13, around theinlet port 23. The other of the opposite ends of the biasingmember 37 is secured to anannular boss 77 that is provided on thetransverse wall 49 ofconcealment member 35, within sub-chamber 73, and that defines theopening 51 intransverse wall 49. Thus, as can be appreciated from a comparison ofFIGS. 22 and 23 , the movement ofconcealment member 35 to expose theindicator member 27 increases tension in the biasing means 37. Termination or interruption of gas flow throughdevice 11 thus results the bias provided bymember 37 returningconcealment member 35 to its position in which it concealsindicator member 27 and preventsmember 27 from being viewed through window portion 53 ofhousing 13. -
FIGS. 25 to 28 show ahousing 12 suitable for thedevice 10 shown inFIGS. 2 to 20 , but with a modification that also can be adopted in thehousing 13 of thedevice 11 ofFIGS. 21 to 24 . The modification is in the provision, along theinner surface 30 of thesidewall 14 ofhousing 12, of a number of longitudinally extending, circumferentially spacedribs 82. In the arrangement shown, there are fourribs 82, although there may only be three (or less) or there may be more than fourribs 82. Theribs 82 preferably are uniformly spaced from each other aroundinner surface 30 ofhousing 12, while the cross section of eachrib 82 is such that it substantially bridges the spacing between theinner surface 30 ofhousing 12 and theouter surface 60 ofskirt 38 ofconcealment member 34 without impeding movement of theconcealment member 34 with or against the bias of the biasingmember 36. Despite this, theribs 82 do serve to centralize theconcealment member 34 during such movement and when stationary.Ribs 82 also serve to obviate noise or vibrations due to theconcealment member 34 rattling or oscillating laterally withinhousing 12 during use ofdevice 10. - It is to be appreciated that while
ribs 82 are illustrated inFIGS. 25 to 28 , other alternative centralizing formations could be provided. For example,inner surface 30 ofsidewall 14 ofhousing 12 could have formed thereon a plurality of small protrusions that are spaced over, both along and around, theinner surface 30. In a further alternative, the centralizing and/or noise reduction formations, such as ribs or protrusions could be provided over theouter surface 60 ofskirt 38 ofconcealment member 34, rather than overinner surface 30 of thesidewall 14 ofhousing 12. -
FIGS. 29 to 32 illustrate alternative construction detail by whichindicator member 26 may be secured concentrically on thehub 58 comprising a continuation ofspigot 56 ofdevice 10 ofFIGS. 2 to 20 . The same alternatives apply to the securement of theindicator member 27 on the hub 59 in thedevice 11 ofFIGS. 21 to 24 . InFIG. 29 , theindicator member 26 is a neat fit onhub 58, such as to provide a strong friction fit or with securement enhanced by a film providing adhesive bonding.FIG. 30 shows an arrangement in whichindicator member 26 is spaced slightly fromhub 58 but is secured by anadhesive bonding layer 84 between the opposed surfaces ofmember 26 andhub 58. In the alternative ofFIG. 31 , more clearly illustrated by the enlarged detail ofFIG. 32 , afusible fin 86 is provided around the end ofindicator member 26 opposed to endwall 44 ofhousing 12 and, when thefin 86 is heated by any suitable arrangement, thefin 86 melts to bond that end ofmember 26 to wall 44. - Further alternatives for securing
indicator member 26 onhub 58 ofdevice 10, with similar possible for securingmember 27 on hub 59 ofdevice 11, are shown inFIGS. 33 and 35 , withFIGS. 34 and 36 providing respective enlarge detail. In the arrangement ofFIGS. 33 and 34 , theindicator member 26 is shown as having an in-turnedflange 88 around the end ofmember 26 remote fromend wall 44 ofhousing 12. Theflange 88 overlaps the adjacent end ofhub 58, with afin 90 onflange 88 bearing against that adjacent end ofhub 58. Heating of thefin 90 by any suitable arrangement enables thefin 90 to melt, withindicator member 26 then able to move more firmly ontohub 58 and be secured byflange 88 being fusion bonded to the adjacent end ofhub 58. In the case ofFIGS. 35 and 36 , there is provided a mechanical securement ofindicator member 26 ontohub 58. For this, the end ofindicator member 26 opposed to endwall 44 ofhousing 12 has an array of circumferentially spaced, axially projecting hookedfingers 92. Asindicator member 26 is moved ontohub 58, eachfinger 92 is forced to elastically flex so as to enter a respective alignedopening 94 throughend wall 44 ofhousing 12. Whenindicator member 26 is fully received ontohub 58, eachfinger 92 is able to elastically recover, to locate its out-turned end against the outer surface ofend wall 44 and thereby lockindicator member 26 onhub 58. -
FIG. 37 and, in particular, the enlarged detail ofFIG. 38 , elaborates on the description above in relation to theviewing window portion 52 of thehousing 12 ofdevice 10 shown inFIGS. 2 to 20 , with the same being applicable to the corresponding features ofdevice 11 ofFIGS. 21 to 24 . As can be recognized from the schematic view ofFIG. 38 , in particular, the longitudinally arcuate form of theouter surface 54 ofhousing 12 within thewindow portion 52, enableswindow portion 52 to function as a magnifying lens. The effect is such that light rays R shown as issuing out fromindicator member 26 diverge out fromwindow portion 52. While the eye E of an observer is depicted as close towindow portion 52, the lens effect is such as to permit viewing ofindicator member 26 from a considerable distance, asindicator member 26 is seen as enlarged relative to its actual size and also to be viewed over a wider viewing angle. These factors, combined with the colour and other highlighting features ofindicator member 26, facilitateindicator member 26 being readily viewed when it is exposed by movement ofconcealment member 34, as a consequence of a desired or required flow of gas through thedevice 10. -
FIGS. 39 to 42 illustrate further variants possible to assist with recognition of the operating condition ofdevice 10 ofFIGS. 2 to 20 , with the same being applicable todevice 11 ofFIGS. 21 to 24 .FIGS. 39 and 41 show the same condition fordevice 10, with the indicator member (not visible) concealed by theconcealment member 34, althoughFIG. 41 shows internal structure consistent with this.FIGS. 40 and 42 also are the same condition fordevice 10, but with theindicator member 26 exposed as a consequence of movement of theconcealment member 34 in response to a required gas flow, althoughFIG. 42 shows internal structure consistent with this. The variant depicted inFIGS. 39 to 42 is the provision of patterning, colouring and texture differences adopted for theexternal surface 60 of theskirt 38 ofconcealment member 34, relative to theouter surface 62 of theindicator member 26. The contrast betweensurfaces surface 60, seen through thewindow portion 52 whenconcealment member 34 is concealing theindicator member 26, from thesurface 62 seen whenindicator member 26 is exposed by movement ofconcealment member 34 as a consequence of a required flow of gas throughdevice 10. Thus, checking that gas is flowing, as required can be even more reliably and readily confirmed. Also, as is evident fromFIGS. 39 to 42 , the length of thehousing 12 between thetransparent window portion 52 and thesecond end 18 may be opaque (or coated with an opaque material or coating, etc.) and of any suitable colour, thereby serving to maximise the visual contrast between the respective conditions in which theindicator member 26 is concealed or exposed. Also, wheredevice 10 is to be one of a series as discussed later herein, that opaque length of thehousing 12 may carry indicia that distinguishes thatdevice 10 from others of the series. - At, or adjacent to the
inlet end respective devices respective chamber end wall hole 96 indevice 10 ofFIGS. 3, 8 and 9 . Alternatively the, or each, opening may be in theside wall respective device end wall end wall nearer end skirt concealment member end skirt end wall chamber end skirt concealment member concealment member member concealment member - As will be appreciated, the gas flow indicator device of the invention enables enhanced ease of observation of a condition, namely exposure of the indicator member, confirming required supply of gas to a patient. With full exposure of the indicator member preferably also confirming that a desired or minimum gas flow rate, such as 6 L/min, has been achieved and is being maintained. The device has components that enable low cost production, readily assembled and provide reliable operation. Also, the device is such that it can be provided in a number of alternative forms each suited to providing a respective required gas flow rate. Thus, for a given standardised biasing member, it is possible to vary performance by selecting from a series of devices that differ in the size of the opening of respective concealment members and, hence, the gas flow rate required to move the concealment member to expose the respective indicator member. Alternatively, a series of devices may have a standardised such opening in the respective concealment members, but differ in the strength of the biasing action of the respective biasing members. Thus, in each case, a respective gas flow rate is required for each device of the series in order to overcome the resistance to flow provided by the respective opening of the concealment member in order for the concealment member to move against the action of the biasing member. The different devices of such series can be readily differentiated by the colour or indicia provided on the outer surface of the skirt of each concealment member, or elsewhere on the device, such as on the housing. Of course, the device also may be provided in a single standardised form, with the gas flow rate at any time within a suitable range of flow rates being apparent from the extent of exposure of the indicator member.
- All components of the device of the invention are able to be of non-ferrous materials, indeed none of the components need be metallic, making the device suitable for use with a face mask supplying gas to a patient while the patient is undergoing an MRI or other procedure precluding metals. Also, the device can be used in any orientation, in contrast for example to apparatus utilising a ball valve type of flow mechanism. Also, the construction of the device is such as to enable continuance of gas supply by minimising the risk of the concealment member becoming snagged, while enabling ongoing gas supply even if the concealment member does become snagged.
- While this invention has been described in connection with specific embodiments thereof, it will be understood that it is capable of further modification(s). The present invention is intended to cover any variations, uses or adaptations of the invention following in general, the principles of the invention and including such departures from the present disclosure as come within known or customary practice within the art to which the invention pertains and as may be applied to the essential features hereinbefore set forth.
- As the present invention may be embodied in several forms without departing from the spirit of the essential characteristics of the invention, it should be understood that the above described embodiments are not to limit the present invention unless otherwise specified, but rather should be construed broadly within the spirit and scope of the invention as defined in the attached claims. Various modifications and equivalent arrangements are intended to be included within the spirit and scope of the invention. Therefore, the specific embodiments are to be understood to be illustrative of the many ways in which the principles of the present invention may be practiced.
- Where the terms “comprise”, “comprises”, “comprised” or “comprising” are used in this specification, they are to be interpreted as specifying the presence of the stated features, integers, steps or components referred to, but not to preclude the presence or addition of one or more other features, integers, steps, components to be grouped therewith.
Claims (21)
1. A gas flow indicator device including an elongate housing that has a peripheral sidewall that extends between first and second opposite ends and that defines a gas flow chamber through which gas is able to flow from an inlet port at a first end to an outlet port at a second end; wherein, within the chamber, the device has a gas flow indicator member that extends from adjacent to the first end of the housing over part of the length of the chamber towards the second end; the indicator member is of annular form such that gas flowing through the chamber from the inlet port to the outlet port enters the chamber along a bore that extends through the indicator member; the indicator member is spaced from an inner surface of the sidewall of the housing to define, with that inner surface, an annular space that forms part of the chamber; the device further includes a concealment member that is movable from the first end of the housing in response to a sufficient pressure generated by gas flow from the inlet port to the outlet port, against the action of a biasing member acting to bias the concealment member to the first end; the concealment member has an annular peripheral skirt that, under the bias of the biasing member on the concealment member, is receivable into the annular space, such that one of opposite ends of the skirt is able to seal against an annular surface of the housing at or adjacent to an end wall of the housing at the first end of the housing; and the concealment member also includes, at the other of the opposite ends of the skirt, a transverse wall that defines an opening through which the flow of gas from the inlet port to the outlet port is able to pass, with the opening providing resistance to such flow; wherein the arrangement is such that the one of opposite ends of the skirt is able to be held in sealing engagement with the annular surface at or adjacent to the end wall of the housing whereby the indicator member is concealed from view, through a laterally adjacent viewing window portion of the housing, when there is no gas flow or a gas flow rate generating less than the sufficient pressure but such that, with increasing gas flow rate the sufficient pressure is achieved and the bias of the biasing member is thereby overcome to enable the concealment member to move towards the second end of the housing and expose the indicator member to view through the viewing window portion of the housing and provide a visual indication indicative of gas flow.
2. The gas flow indicator device of claim 1 , wherein movement of the concealment member to expose the indicator member moves the one of opposite ends of the skirt of the concealment member from the annular surface at or adjacent to the end wall of the housing, such as thereby to enable a secondary gas flow to the outlet that passes around the one of opposite ends of the skirt between the concealment member and the housing.
3. The gas flow indicator device of claim 1 , wherein the biasing member acts in compression in biasing the concealment member to the first end of the housing, such as by the biasing member being compressed between, such as compressed by, the concealment member and the second end so as to provide the required bias in seeking to expand.
4. The gas flow indicator device of claim 1 , wherein the biasing member acts in tension in biasing the concealment member to the first end of the housing, such as by the biasing member being within the concealment member, and tensioned by being expanded between, such as by being connected in relation to, each of the transverse wall of the concealment member and the first end of the housing so as to provide the bias in seeking to contract.
5. The gas flow indicator device of claim 1 , wherein the biasing member comprises a coil spring.
6. The gas flow indicator device of claim 3 , wherein the biasing member comprises a coil spring acting between the concealment member and the second end of the housing, and wherein compression of the spring can limit the extent to which the concealment member can move towards the second end of the housing simply as a consequence of the presence of the compressed spring.
7. The gas flow indicator device of claim 4 , wherein the biasing member comprises a coil spring within the concealment member, with the arrangement such that the concealment member is able to move so as to contact the end wall at the second end of the housing, or such that contact of the concealment member with the second end of the housing is precluded by the spring reaching its elastic limit.
8. The gas flow indicator device of claim 1 , wherein the concealment member is able to move, between a first position in which the indicator member is concealed and a second position in which the indicator member is sufficiently exposed whereby the indicator member can readily be seen through the viewing window portion of the sidewall of the housing by a person in close proximity and also from a considerable distance of up to five to ten meters, or further, from the device.
9. The gas flow indicator device of claim 8 , wherein the viewing window portion is sufficiently transparent to facilitate viewing of the indicator member, and wherein the viewing window portion extends around the full circumferential extent of the sidewall of the housing adjacent to the first end, or comprises two or more regions spaced circumferentially around that wall of the housing adjacent to the first end.
10. The gas flow indicator device of claim 8 , wherein the viewing window portion is of a high-transparency plastics or glass material having a high level of clarity, and wherein the material of which the remainder of the housing is made is transparent, translucent or opaque.
11. The gas flow indicator device of claim 8 , wherein the housing is of unitary or integral form and made of a single material comprising a rigid plastics material or an engineering plastics material.
12. The gas flow indicator device of claim 1 , wherein the housing is circular in cross-sections perpendicular to the direction of spacing between the first and second ends, with the housing having an inner surface that is substantially cylindrical and of substantially constant circular transverse cross-section between the first and second ends, and with the sidewall also having an outer surface that is substantially cylindrical and of substantially constant circular cross-section.
13. The gas flow indicator device of claim 12 , wherein the housing has an outer surface of the sidewall that departs from a cylindrical form, at least along an initial section of its longitudinal extent from adjacent to the first end, with that initial section extending around the gas flow indicator member, and wherein the outer surface of the sidewall, over that initial section of its longitudinal extent, smoothly increases in diameter to a maximum in a direction away from the first end towards the second end, and thereafter smoothly decreases in diameter substantially to the diameter at the first end, so as to have a convex longitudinal form.
14. The gas flow indicator device of claim 1 , wherein at the first end of the housing, the inlet port is defined by a spigot that projects from the first end of the housing in a direction away from the second end, and that enables connection of a gas supply conduit to the housing.
15. The gas flow indicator device of claim 14 , wherein the spigot has an extension that projects into the interior of the housing to provide a hub on or around which the gas flow indicator member is mounted, with the indicator member preferably having an axial extent that is substantially the same as, or slightly greater than, the length of the hub, with the indicator member being a firm friction fit on the hub or by the indicator member being bonded or welded onto the hub, or by the indicator member having an end, adjacent to the end wall at the first end of the housing, by which the indicator member is bonded or welded to the end wall or the indicator member has, at its end remote from the first end of the housing, a flange that overlaps the corresponding end of the hub, with the flange bonded or welded to that end of the hub.
16. The gas flow indicator device of claim 14 , wherein the indicator member is bonded or welded to an end wall of the housing at the first end, or mechanically engaged with that end wall by screw-threaded engagement or a snap fit in or around the inlet port.
17. The gas flow indicator device of claim 1 , wherein the skirt of the concealment member has an outer surface that is spaced from the inner surface of the sidewall of the housing, with a spacing between the surfaces throughout the extent of movement of the concealment member longitudinally within the housing.
18. The gas flow indicator device of claim 17 , further including guide members that maintain the concealment member in a substantially co-axial relationship with the housing, such guide members preferably comprising a plurality of circumferentially spaced projections that stand proud, or project inwardly, of the inner surface of the housing so as to be contactable with the outer surface of the skirt of the concealment member, or the converse, or a plurality of longitudinal ribs on the inner surface of the sidewall of the housing or the outer surface of the concealment member.
19. The gas flow indicator device of claim 1 , wherein the inner surface of the skirt of the concealment member, when the indicator member is concealed, is spaced from the outer peripheral surface of the indicator member, thereby avoiding contact between the skirt of the concealment member and the indicator member, and thereby obviates friction that could resist movement of the concealment member relative to the indicator member, with the skirt of the concealment member and the indicator member each being of substantially uniform wall thickness along its respective axial extent and of similar or substantially the same wall thickness.
20. The gas flow indicator device of claim 1 , wherein at the second end, the housing has an end wall that defines the outlet port, with the end wall preferably being separable from the sidewall of the housing, such as by the end wall comprising an annular peripheral rim that is engaged with the sidewall of the housing around the second end, a central hub portion and a plurality of circumferentially spaced connectors that extend between the rim and the hub.
21. A gas delivery device, gas delivery system or gas supply conduit including the gas flow indicator device of claim 1 .
Priority Applications (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
US16/392,705 US20190269875A1 (en) | 2016-12-29 | 2019-04-24 | Gas Flow Indicator Device |
Applications Claiming Priority (2)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
US15/393,404 US10307558B2 (en) | 2016-12-29 | 2016-12-29 | Gas flow indicator device |
US16/392,705 US20190269875A1 (en) | 2016-12-29 | 2019-04-24 | Gas Flow Indicator Device |
Related Parent Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
US15/393,404 Continuation US10307558B2 (en) | 2016-12-29 | 2016-12-29 | Gas flow indicator device |
Publications (1)
Publication Number | Publication Date |
---|---|
US20190269875A1 true US20190269875A1 (en) | 2019-09-05 |
Family
ID=62712236
Family Applications (2)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
US15/393,404 Active 2037-05-29 US10307558B2 (en) | 2016-12-29 | 2016-12-29 | Gas flow indicator device |
US16/392,705 Abandoned US20190269875A1 (en) | 2016-12-29 | 2019-04-24 | Gas Flow Indicator Device |
Family Applications Before (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
US15/393,404 Active 2037-05-29 US10307558B2 (en) | 2016-12-29 | 2016-12-29 | Gas flow indicator device |
Country Status (1)
Country | Link |
---|---|
US (2) | US10307558B2 (en) |
Cited By (1)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US11389604B2 (en) | 2017-06-28 | 2022-07-19 | Vpas Group Pty Ltd | Gas flow indicator device |
Families Citing this family (3)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JP1602508S (en) * | 2017-09-22 | 2018-04-23 | ||
US11344695B2 (en) * | 2018-05-14 | 2022-05-31 | Praxair Technology, Inc. | Gas flow arrestor |
EP3755411A1 (en) * | 2019-05-09 | 2020-12-30 | Mirola IP AB | A flow indicator for oxygen addition to rebreathing systems |
Family Cites Families (58)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US828108A (en) | 1905-08-05 | 1906-08-07 | Arvilla M Graham | Visible fluid-feed indicator. |
US2389282A (en) * | 1944-01-13 | 1945-11-20 | Bausch & Lomb | Magnifying device |
US2662502A (en) | 1952-11-12 | 1953-12-15 | Ralph R Turner | Flow indicator for hose |
US2843121A (en) | 1955-05-20 | 1958-07-15 | Charles H Hudson | Oxygen mask |
US3119369A (en) * | 1960-12-28 | 1964-01-28 | Ametek Inc | Device for indicating fluid flow |
US3256876A (en) | 1962-03-06 | 1966-06-21 | Air Shields | Volume indicator for anesthesia machine system |
DE1176885B (en) | 1962-08-30 | 1964-08-27 | Bopp & Reuther Gmbh | Speed counter for flowing media with a paddle wheel or the like as a measuring element |
US3408865A (en) * | 1966-10-13 | 1968-11-05 | Roy L. Chenault | Fluid flow indicating meter |
US3650599A (en) * | 1971-01-28 | 1972-03-21 | Carl Pedersen | Measuring instrument and reading device assembly |
DE2151786A1 (en) | 1971-10-18 | 1973-04-26 | Bockemuehl Johannes Fa | DEVICE FOR THE DOSED FEEDING OF WATER TAKEN FROM A WATER TAP TO A WASHING DEVICE |
US3890967A (en) | 1973-10-17 | 1975-06-24 | James O Elam | Breathing indicator and ventilator |
US4098271A (en) | 1975-09-29 | 1978-07-04 | Mcdonnell Douglas Corporation | Oxygen supply system and flow indicator |
US4064751A (en) | 1976-10-18 | 1977-12-27 | Elematic Instrument Corporation | Flowmeter |
US4136560A (en) * | 1976-12-27 | 1979-01-30 | Gellos Alexander T | Pressure gauge |
USD256000S (en) | 1978-04-07 | 1980-07-22 | Mobil Oil AB Sweden | Fluid flow indicator |
SE8102452L (en) | 1980-04-16 | 1981-10-17 | Taco Armaturen Ag | FLOW TYPE CONTROL DEVICE |
USD266316S (en) | 1980-10-27 | 1982-09-28 | Tsi Incorporated | Fluid flow measuring head |
US4745877A (en) | 1987-01-12 | 1988-05-24 | Chang Shih Chih | Rotary sight flow indicator |
US4763114A (en) * | 1987-07-09 | 1988-08-09 | Eidsmore Paul G | Fluid flow indicator |
DE3724179A1 (en) | 1987-07-22 | 1989-02-02 | Klaus Dipl Ing Kobold | METHOD FOR MEASURING THE FLOW OF LIQUID MEDIA AND THE FLOW METER FOR IMPLEMENTING SUCH A METHOD |
US4945918A (en) | 1988-05-04 | 1990-08-07 | Abernathy Charles M | Method and apparatus for monitoring a patient's circulatory status |
US4986128A (en) * | 1989-12-22 | 1991-01-22 | The Devilbiss Company | In-line pressure gauge |
US5038773A (en) | 1990-06-08 | 1991-08-13 | Medical Graphics Corporation | Flow meter system |
US5337617A (en) | 1993-04-08 | 1994-08-16 | John Dimeff | Gas flow meter |
US5343859A (en) | 1993-06-17 | 1994-09-06 | Puritan-Bennett Corporation | Passenger oxygen mask having internal flow confirmation balloon |
US5845597A (en) | 1994-03-15 | 1998-12-08 | Vista Water Systems, Inc. | Separation medium efficiency indicator |
US5606131A (en) | 1995-11-27 | 1997-02-25 | Smiths Industries Medical Systems, Inc. | Piston manometer with spring constant dependent upon position |
US5857460A (en) | 1996-03-14 | 1999-01-12 | Beth Israel Deaconess Medical Center, Inc. | Gas-sensing mask |
US5911219A (en) | 1997-04-18 | 1999-06-15 | Aylsworth; Alonzo C. | Therapeutic gas flow meter and monitor |
US6338279B1 (en) | 1999-11-23 | 2002-01-15 | Eddie J. Tsataros | Flow detector to monitor a number of flow events or duration |
US6386196B1 (en) | 2000-03-13 | 2002-05-14 | Steven E. Culton | Warning device for oxygen delivery system failure |
US7055520B2 (en) | 2001-01-17 | 2006-06-06 | David Swisa | Device and method for detecting the flow of a gas |
US7004168B2 (en) | 2001-09-07 | 2006-02-28 | Respironics, Inc. | Face mask for gas monitoring during supplemental oxygen delivery |
US7040319B1 (en) | 2002-02-22 | 2006-05-09 | The United States Of America As Represented By The National Aeronautics And Space Administration | Method and apparatus for monitoring oxygen partial pressure in air masks |
US7159533B1 (en) | 2002-09-12 | 2007-01-09 | Iris Gail Redd | System and method for monitoring the delivery of gas to a person's airway |
US7730847B1 (en) | 2002-09-12 | 2010-06-08 | Redd Iris H | Personal, wearable, disposable breathing-gas flow indicator |
US20050205098A1 (en) | 2004-03-19 | 2005-09-22 | Samsun Lampotang | Apparatus and method to deliver dilute O2 by nasal cannula or facemask |
GB2418738A (en) | 2004-10-02 | 2006-04-05 | David Arthur Jones | A fluid flow sensor |
US7013726B1 (en) | 2004-11-22 | 2006-03-21 | Invacare Corporation | Fluidic demand apparatus and MEMS flow sensor for use therein |
US20060130838A1 (en) | 2004-12-20 | 2006-06-22 | Lee Yong Y | Data logger for monitoring asthmatic conditions |
AU304760S (en) | 2005-03-16 | 2005-12-19 | Crane John Safematic Oy | Flowmeter |
WO2006106632A1 (en) * | 2005-04-04 | 2006-10-12 | Koganei Corporation | Fluid flow direction display device |
KR100669092B1 (en) | 2005-05-27 | 2007-01-15 | 삼성전자주식회사 | Apparatus for monitoring particles in air |
WO2007098565A1 (en) | 2006-03-03 | 2007-09-07 | Keystone Product Developments Pty Ltd | Fluid flow indicator |
US20070221223A1 (en) * | 2006-03-10 | 2007-09-27 | Mcdermott Francis | Cannula gas flow meter |
DE102007052898B3 (en) | 2007-11-07 | 2009-04-30 | Dräger Medical AG & Co. KG | Device for the discharge of breathing gas |
US20090145349A1 (en) | 2007-12-07 | 2009-06-11 | Hebert William C | Fluid Flow Indicator |
US20090165801A1 (en) | 2007-12-31 | 2009-07-02 | Nellcor Puritan Bennett Llc | Carbon dioxide detector having an acrylic based substrate |
US20090301474A1 (en) | 2008-06-05 | 2009-12-10 | Neil Alex Korneff | Heat and moisture exchange unit with resistance indicator |
US8783247B2 (en) * | 2009-02-04 | 2014-07-22 | Wet Nose Technologies, Llc. | Pressure release systems, apparatus and methods |
US20120055471A1 (en) | 2010-09-05 | 2012-03-08 | Slp Ltd. | Valve accessory for aiding speech during non-invasive respiratory therapy |
US9004068B2 (en) | 2011-05-25 | 2015-04-14 | Scott Technologies, Inc. | High pressure air cylinders for use with self-contained breathing apparatus |
US20120325215A1 (en) | 2011-06-23 | 2012-12-27 | Levenick William R | Self powered universal gas flow indicator |
USD657399S1 (en) | 2011-07-19 | 2012-04-10 | Smc Corporation | Fluid pressure cylinder |
WO2014026221A1 (en) | 2012-08-12 | 2014-02-20 | Vpas Group Pty Ltd | Gas flow indicator |
TWI494552B (en) * | 2013-02-01 | 2015-08-01 | Wen San Chou | Manometer |
US9310228B1 (en) * | 2013-03-04 | 2016-04-12 | James E. Rapp | Compressed air indicator |
JP6042847B2 (en) | 2014-07-04 | 2016-12-14 | 大陽日酸株式会社 | Gas flow indicator |
-
2016
- 2016-12-29 US US15/393,404 patent/US10307558B2/en active Active
-
2019
- 2019-04-24 US US16/392,705 patent/US20190269875A1/en not_active Abandoned
Cited By (1)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US11389604B2 (en) | 2017-06-28 | 2022-07-19 | Vpas Group Pty Ltd | Gas flow indicator device |
Also Published As
Publication number | Publication date |
---|---|
US10307558B2 (en) | 2019-06-04 |
US20180188094A1 (en) | 2018-07-05 |
Similar Documents
Publication | Publication Date | Title |
---|---|---|
US20190269875A1 (en) | Gas Flow Indicator Device | |
US10314988B2 (en) | Gas flow indicator | |
US20230302241A1 (en) | Breath indicator | |
EP2102538B1 (en) | Safety valve | |
US20120048278A1 (en) | Oropharyngeal and nasopharyngeal airway having a breathing indicator | |
US11389604B2 (en) | Gas flow indicator device | |
US10660543B2 (en) | Breathing detection apparatus | |
WO2018119487A1 (en) | Gas flow indicator device | |
EP3342443B1 (en) | Gas flow indicator device | |
AU2016277769B2 (en) | Gas Flow Indicator Device | |
EP2035812B1 (en) | Respiratory assembly including a carbon dioxide detector | |
AU750212B2 (en) | Breathing masks | |
Crosby et al. | The anaesthetic machine | |
KR102282071B1 (en) | Larynx mask apparatus |
Legal Events
Date | Code | Title | Description |
---|---|---|---|
AS | Assignment |
Owner name: VPAS GROUP PTY LTD, AUSTRALIA Free format text: ASSIGNMENT OF ASSIGNORS INTEREST;ASSIGNOR:MATUSIK, MATTHEW;REEL/FRAME:048977/0889 Effective date: 20161223 |
|
STPP | Information on status: patent application and granting procedure in general |
Free format text: DOCKETED NEW CASE - READY FOR EXAMINATION |
|
STPP | Information on status: patent application and granting procedure in general |
Free format text: NON FINAL ACTION MAILED |
|
STCB | Information on status: application discontinuation |
Free format text: ABANDONED -- FAILURE TO RESPOND TO AN OFFICE ACTION |