Patent Application
20220143357
The present invention relates to medical devices such as humidifiers and liquid reservoirs, and methods for using such devices. More specifically, the present invention relates to improved liquid reservoirs for medical devices and humidifiers that are safer, and methods for using such devices.
Medical devices, such as humidifiers are known to provide humidified air to a user, typically patients in hospitals, hospices, and even at home, so as to prevent illness, soothe symptoms, etc. Humidifiers often contain a liquid reservoir, or a water reservoir, which is placed upon a heating plate and is connected to an air pathway such as a breathing circuit. Typically a blower pushes air through the air pathway, the heater plate heats up the liquid in the liquid chamber, and then the air becomes humidified and then proceeds downstream along the breathing circuit.
One of the major technical challenges with humidifiers is that they need to be able to detect when the liquid reservoir is empty, and/or when the liquid reservoir is not installed properly and/or not present at all. This prevents the heater plate from continuing to heat up, potentially leading to damage, a fire, injury, excessive energy use, etc.
Current methods include the use of weight sensors, electrical sensors, voltage sensors, etc. which tend to be a bit inaccurate, especially in environments with varying conditions such as temperature, ventilation, etc.
Accordingly, there exists a need for improved liquid reservoir presence detection methods and apparatuses, and also for improved liquid presence detection methods and apparatuses. It is also desirable to have more accurate liquid presence detection methods and apparatuses.
An embodiment of the present invention relates to a liquid reservoir for a humidifier containing a base, a top portion opposite the base, a side wall, and a liquid presence indicator. The side wall contains a lower side wall portion adjacent to the base, and an upper side wall portion adjacent to the top portion. The liquid presence indicator interacts with the humidifier to detect the presence of liquid in the liquid reservoir.
In an embodiment of the present invention, the present invention relates to a humidifier containing a liquid reservoir as described herein. The humidifier further contains a power source, a controller operatively-connected to the power source, and a liquid presence detector operatively-connected to the controller. The liquid presence detector interacts with the liquid presence indicator to detect the presence of liquid within the liquid reservoir.
In an embodiment herein, a method of use of the humidifier and/or the medical device herein, may further include the steps of providing the humidifier and/or medical device herein, emitting light from the light emitter, reflecting light from the substantially flat surface to form reflected light, detecting the reflected light by the light sensor, generating light sensor data, transmitting the light sensor data to the controller, comparing the light sensor data to a threshold value, and determining whether to terminate power to the heater plate.
Without intending to be limited by theory, it is believed that the present invention may provide one or more benefits such as more accurate liquid detection, a reduced chance of overheating, a reduced chance of heat damage, a reduced chance of fires, a reduced chance of a user/patient receiving unhumidified air, etc.
The figures herein are for illustrative purposes only and are not necessarily drawn to scale.
Unless otherwise specifically provided, all measurements are made in metric units. Furthermore, all percentages, ratios, etc. herein are by weight, unless specifically indicated otherwise.
Unless otherwise specifically provided, all measurements are made in metric units. Furthermore, all percentages, ratios, etc. herein are by weight, unless specifically indicated otherwise.
As used herein the term “operatively-connected” indicates that the item(s) is(are) connected in a manner which allows them to operate. This may involve, for example, wires, a transmitter/receiver pair, a pair of transceivers, etc. This phrase may also indicate that a physical structure connects the various indicated items.
Unless otherwise specifically described all of the devices, items and/or parts herein may be made from industry-standard materials which are available from multiple suppliers worldwide.
An embodiment of the present invention relates to a liquid reservoir for a humidifier containing a base, a top portion opposite the base, a side wall joining the base and the top portion, and a liquid presence indicator, where the liquid presence indicator contains a substantially flat surface. The side wall contains a lower side wall portion adjacent to the base, and an upper side wall portion adjacent to the top portion. When the liquid presence indicator interacts with the humidifier to detect the presence the liquid in the liquid reservoir.
Typically when the medical device; or the humidifier, does not detect the presence of the liquid reservoir, and/or liquid within the liquid reservoir, then the controller will terminate the power to the heater plate to reduce the chance of burning, damage, fire, and/or excessive energy use.
It is known that the refractive index of air is about 1, while the refractive index of water is about 1.3. In an embodiment herein, the liquid presence indicator contains a substantially flat surface; or a flat surface; or a prism; or contains a material which possesses a refractive index of from about 1.1 to about 1.9; or from about 1.2 to about 1.65, or from about 1.3 to about 1.6; or having a refractive index of from about 1.1 to about 1.9; or from about 1.2 to about 1.65, or from about 1.3 to about 1.6, with respect to the wavelength of light from the light emitter; or the infrared spectrum. In an embodiment herein, the liquid reservoir's side wall is formed of polycarbonate having a refractive index of about 1.6. In an embodiment herein, the substantially flat surface; or the flat surface; or the prism is formed of polycarbonate having a refractive index of about 1.6.
In an embodiment herein, the liquid reservoir's side wall and the substantially flat surface; or the flat surface; or the prism may be formed of, or comprise, the same material. Without intending to be limited by theory, it is believed that such a feature allows easier production and/or moulding of the liquid reservoir, and may be cheaper from both a raw material cost and manufacturing point of view.
In an embodiment herein, the liquid presence indicator is located at least 1 mm above; or from about 1 mm to about 2 cm above; or from about 2 mm above to about 1.5 mm above; or from about 0.5 mm above; to about 1.25 cm above the base of the liquid reservoir. Without intending to be limited by theory, it is believed that as the heater plate will still contain sufficient heat to continue to evaporate the liquid for a short period of time after the power flowing thereto is terminated, then by designing the liquid presence indicator to be above the base of the liquid reservoir, it will reduce the chances of the liquid reservoir running dry and/or overheating due to the lack of liquid; or water. As used herein the liquid presence location is indicated by where the corresponding liquid presence detector is located and at which level it detects a liquid within the liquid reservoir.
In an embodiment herein, the liquid presence indicator reflects and refracts light so as to detect whether or not sufficient liquid is present. In an embodiment herein, the liquid presence detector contains a light emitter and a corresponding light sensor both operatively-connected to the controller. The light emitter emits an amount of light which then impinges upon the liquid reservoir, and is refracted and reflected by the substantially flat surface of the liquid presence indicator by varying amounts depending upon whether liquid; or sufficient liquid, is present in the liquid reservoir. An amount of light is then refracted into the inside of the liquid reservoir, and an amount of light is reflected out of the liquid reservoir, and to the light sensor. The controller calculates the ratio between the amount of light emitted by the light emitter and the amount of light received by the light sensor; or requires a pre-determined threshold of light to be detected by the light sensor, to determine whether liquid; or sufficient liquid, is present in the liquid reservoir.
In an embodiment herein, if the amount of light received by the light sensor is less than 30% of the amount of light emitted by the light emitter, then the controller determines that liquid; or a sufficient amount of liquid, is present in the liquid reservoir. In an embodiment herein, if the amount of light received by the light sensor is 30% or more of the amount of light emitted by the light emitter, then the controller determines that no liquid; or an insufficient amount of liquid, is present in the liquid reservoir.
Without intending to be limited by theory, it is believed that the liquid presence detector herein in conjunction with the liquid reservoir herein reduces the chance of the liquid reservoir running dry, overheating, and/or causing a fire or other hazard. The liquid presence detector and liquid reservoir described herein are easily manufactured, and contain no moving parts, which reduces wear and tear on the parts. Without intending to be limited by theory, it is believed that the liquid presence detector herein in conjunction with the liquid reservoir herein advantageously-provide improvements over, for example, a scale, which contains moving parts. It is believed that the present invention provides long-term, low-maintenance accuracy with a minimum of moving parts and manufacturing complexity and investment.
In an embodiment herein, the liquid reservoir further contains a liquid reservoir presence indicator. The liquid reservoir presence indicator interacts with the humidifier to detect the presence of the liquid reservoir. In an embodiment herein, the liquid reservoir presence indicator is formed of a reflective material, such as, for example, foil, a sticker, and a combination thereof; or an adhesive foil, and a combination thereof; or an adhesive gold foil, an adhesive silver foil, an adhesive mylar foil, and a combination thereof. Such a feature is especially useful when the corresponding liquid reservoir presence detector employs light; or infrared light.
In an embodiment herein, the side wall contains the liquid presence indicator, the liquid reservoir presence indicator, or both the liquid presence indicator and the liquid reservoir presence indicator.
In an embodiment herein, a medical device; or a humidifier; or a medical device containing a humidifier, may contain the liquid reservoir described herein. Specifically in an embodiment herein, the humidifier may further contain a power source, a controller operatively-connected to the power source, an optional heater plate, an optional liquid reservoir presence detector, and a liquid presence detector. The liquid presence detector is operatively-connected to the controller for interacting with the liquid presence indicator to detect the presence of liquid; or sufficient liquid, within the liquid reservoir.
If present, then the heater plate is operatively-connected to the controller, and the base of the liquid reservoir is to be placed on the heater plate. The base may then be heated by the heating plate.
If present, then the liquid reservoir presence detector is operatively-connected to the controller for interacting with the liquid reservoir presence indicator so as to detect the presence of the liquid reservoir.
The controller may control the amount of power flowing to the heater plate. If the liquid presence detector does not detect the presence of liquid; or an insufficient amount of liquid, then the controller may terminate the power source to the heater plate, may initiate an alarm, or otherwise attempt to notify the user/operator/patient. If the optional liquid reservoir presence detector does not detect the presence of the liquid reservoir, then the controller may terminate the power flowing to the heater plate, may initiate an alarm, or otherwise attempt to notify the user/operator/patient.
Only when the liquid presence detector detects the presence of liquid in the liquid reservoir and the optional liquid presence detector detects the presence of the liquid reservoir, does the controller allow power to flow to the heater plate.
In an embodiment herein, the optional liquid reservoir detector does not contain a scale and/or does not operate by weight. In an embodiment herein, the liquid presence detector does not contain a scale and/or does not operate by weight. In an embodiment herein, neither the liquid presence reservoir detector nor the liquid presence detector contains a scale and/or operates by weight.
In an embodiment herein, the optional liquid reservoir presence detector employs light; or a light selected from the group of visible light, infrared light, ultraviolet light, and a combination thereof; or infrared light.
In an embodiment herein, the liquid reservoir presence detector contains a light emitter and a light sensor. The light emitter emits light which then impinges upon the liquid reservoir presence indicator. Or, the light impinges on the liquid reservoir presence indicator and reflects from the liquid reservoir presence indicator. The light sensor then detects the light impinging on the liquid reservoir presence detector, or the light reflected from the liquid reservoir presence indicator. When the liquid reservoir presence detector's light sensor detects the light impinging on the liquid reservoir presence detector, or the light reflected from the liquid reservoir presence indicator, then the controller may maintain the power flowing to the heater plate. However, if the liquid reservoir presence detector's light sensor fails to detect the light impinging on the liquid reservoir presence detector, or fails to detect the light reflected from the liquid reservoir presence indicator, then the controller may terminate the power flowing to the heater plate, may initiate an alarm, or otherwise attempt to notify the user/operator/patient. Without intending to be limited by theory, it is believed that such a feature may prevent the controller from providing power to the heating plate when a liquid reservoir is not present, may indicate to the user/operator/patient to turn off the heater plate and/or to properly affix a liquid reservoir, and therefore prevent overheating of the heater plate so as to reduce the chance for accidents, damage, fire, etc.
In an embodiment herein, the liquid reservoir presence detector and the liquid presence detector are included together in a detector suite, which may reduce the chance of the light emitter and the light sensor from being jostled out of alignment, and may further protect the light emitter and light sensor from damage.
In an embodiment herein, the liquid presence detector employs light; or light selected from the group of visible light, infrared light, ultraviolet light, and a combination thereof; or infrared light; or infrared light of a wavelength of about 760 nm to about 1 mm; or from about 895 nm to about 985 nm.
In an embodiment herein, the liquid presence detector contains a light emitter and a light sensor. The light emitter emits an amount of light which then impinges upon the liquid presence indicator. When the light impinges on the liquid presence indicator a portion of it reflects from the substantially flat surface of the liquid presence indicator; or flat surface and a portion of the light refracts from the substantially flat surface of the liquid presence indicator. The light sensor then detects the amount of light reflecting from the substantially flat surface of the liquid presence indicator and feeds this information to the controller. The controller then uses this information to determine whether liquid; or sufficient liquid, is present in the liquid reservoir. The controller may determine this by, for example, checking whether or not the amount of light detected by the light sensor is above a threshold amount. In an embodiment herein, the threshold amount is 30% or more of the light expected to be emitted by the light emitter.
When the condition of liquid; or sufficient liquid, present in the liquid reservoir is determined by the controller, then the controller maintains the power flowing to the heater plate. However, if the controller determines that no liquid' or insufficient liquid is present in the liquid reservoir, then the controller terminates the power flowing to the heater plate. Without intending to be limited by theory, it is believed that such a feature prevents the controller from providing power to the heating plate when the liquid reservoir is empty of liquid, and therefore prevents overheating of the (empty) liquid reservoir so as to reduce the chance for accidents, damage, fire, etc.
The light emitters and light sensors herein are industry-standard and may be procured from a variety of suppliers worldwide.
In an embodiment herein, the humidifier; or the medical device; or the medical device containing the humidifier, further contains an additional component; or an additional component selected from a clock, an alarm, an breathing circuit, a heating circuit for the breathing circuit, a communication device, and a combination thereof. Such items are standard components and well-known by those skilled in the art.
Turning to the figures,
The liquid reservoir herein is typically a transparent or translucent, hollow container, 22, which is made of heat-resistant materials such as high density plastic, glass, metal, and a combination thereof; or polypropylene, polycarbonate, aluminium, and a combination thereof; or polycarbonate, aluminium, and a combination thereof. Typically, the base, 12, contains a metal, such as aluminium, so as to provide both heat resistance as well as good thermal conductivity from the heater plate (see
The liquid reservoir contains the liquid; or water; or distilled water; or sterile water, which is evaporated to create the humidified air. The liquid reservoir is operatively-connected; or fluidly-connected, to an air pathway, 24, such as a breathing circuit (see
The liquid reservoir, 10, further contains a liquid reservoir presence indicator, 26, on the side wall, 16, as well as a liquid presence indicator, 28, which in this embodiment is a prism (see
As the index of refraction of polycarbonate is similar to that of water, when the liquid reservoir, 10 is filled with water; or distilled water, then as seen in
In
In the view of
The manual latch, 46, keeps the liquid reservoir, 10, securely-attached to the humidifier, 42.
In contrast,
In an embodiment of the present invention, the liquid reservoir and the humidifier and/or medical device herein may be used by providing the humidifier described herein, containing the liquid reservoir described herein. The method of use may further include the steps of emitting light from the light emitter, reflecting light from the substantially flat surface to form reflected light, detecting the reflected light by the light sensor, generating light sensor data, transmitting the light sensor data to the controller, comparing the light sensor data to a threshold value, and determining whether to terminate power to the heater plate.
In an embodiment herein, the controller may compare the light sensor data to a threshold value; or a pre-determined value; or a percentage of the total amount typically emitted by the light emitter. The threshold value may be, for example, a pre-determined value; or a percentage of the total amount typically emitted by the light emitter. In an embodiment herein, the threshold value, and/or the pre-determined value may be 30% of the amount of light expected to be emitted by the light emitter. Accordingly, if the amount of light received by the light sensor is less than 30% of the amount of light emitted by the light emitter, then the controller determines that liquid; or a sufficient amount of liquid, is present in the liquid reservoir. In an embodiment herein, if the amount of light received by the light sensor is 30% or more of the amount of light emitted by the light emitter, then the controller determines that no liquid; or an insufficient amount of liquid, is present in the liquid reservoir.
In an embodiment herein, the steps of comparing the light sensor data to a threshold value and determining whether to terminate power to the heater plate are conducted by the controller.
If it is determined, for example, by the controller, that the power to the heater plate should be terminated, then in an embodiment herein the method further contains the step of terminating the power to the heater plate.
In some cases, it may be desirable for the humidifier, or medical device to send a signal, either instead of, or in addition to terminating the power flowing to the heater plate. Accordingly, an embodiment of the present invention further contains the step of transmitting a signal. The signal could be a wireless signal, an electrical signal, etc. as desired, and may be intended to, for example, sound an alarm, notify the user, notify a caregiver, notify a nurse, etc. The signal could be, for example intended to indicate the low liquid level in a hospital system, on a mobile phone app, activate an audible alarm, etc. as desired. In an embodiment herein, the signal may cause the liquid reservoir to automatically fill up again.
Furthermore, it is recognized that the steps of emitting light from the light emitter, reflecting light from the substantially flat surface to form reflected light, detecting the reflected light by the light sensor, generating light sensor data, transmitting the light sensor data to the controller, comparing the light sensor data to a threshold value, and determining whether to terminate power to the heater plate may be repeated; or repeated on a regular basis, to constantly determine whether sufficient liquid is present in the liquid reservoir. Accordingly, in an embodiment of the present invention the steps of emitting light from the light emitter, reflecting light from the substantially flat surface to form reflected light, detecting the reflected light by the light sensor, generating light sensor data, transmitting the light sensor data to the controller, comparing the light sensor data to a threshold value, and determining whether to terminate power to the heater plate are repeated from about 0.1 times per minute (i.e., 1 time per 10 minutes) to about 100 times per minute; or from about 0.2 times per minute (i.e., 1 time per 5 minutes) to about 75 times per minute; or from about 0.5 times per minute (i.e., 1 time per 2 minutes) to about 25 times per minute.
It should be understood that the above only illustrates and describes examples whereby the present invention may be carried out, and that modifications and/or alterations may be made thereto without departing from the spirit of the invention.
It should also be understood that certain features of the invention, which are, for clarity, described in the context of separate embodiments, may also be provided in combination in a single embodiment. Conversely, various features of the invention which are, for brevity, described in the context of a single embodiment, may also be provided separately, or in any suitable subcombination.
All references specifically cited herein are hereby incorporated by reference in their entireties. However, the citation or incorporation of such a reference is not necessarily an admission as to its appropriateness, citability, and/or availability as prior art to/against the present invention.
| Filing Document | Filing Date | Country | Kind |
|---|---|---|---|
| PCT/CN2019/090390 | 6/6/2019 | WO | 00 |
