阅读说明：本技术 一种改进的加热器板 (Improved heater plate ) 是由 雷宇 徐结兵 于海滨 胡振湘 赵军 于 2019-06-06 设计创作，主要内容包括：一种用于加湿器的加热器板(1),包含具有顶部表面(12)和与顶部表面(12)相反的底部表面(14)的导热板(10)。温度传感器(16)固定至底部表面(14)并且导热层(18)直接固定至底部表面(14)。陶瓷加热元件(20)直接固定至导热层(18)。加湿器和医疗设备也可以包含该加热器板(1)。(A heater plate (1) for a humidifier comprises a thermally conductive plate (10) having a top surface (12) and a bottom surface (14) opposite the top surface (12). The temperature sensor (16) is secured to the bottom surface (14) and the thermally conductive layer (18) is secured directly to the bottom surface (14). The ceramic heating element (20) is directly fixed to the heat conductive layer (18). Humidifiers and medical devices may also incorporate the heater plate (1).)

1. A heater plate for a humidifier, the heater plate comprising:

A) a thermally conductive plate comprising a top surface and a bottom surface opposite the top surface;

B) a temperature sensor secured to the bottom surface;

C) a thermally conductive layer directly secured to the bottom surface; and

D) a ceramic heating element directly secured to the thermally conductive layer.

2. The heater plate according to claim 1, wherein the temperature sensor is directly fixed to the bottom surface.

3. The heater plate according to any one of the preceding claims, comprising a plurality of heating elements distributed over the bottom surface, and wherein the temperature sensor is located between at least two heating elements.

4. The heater plate according to any one of the preceding claims, further comprising a slot in which the heating element is located.

5. The heater plate according to any one of the preceding claims, further comprising a switch positioned below the bottom surface; or a pressure sensitive switch; or a protection switch.

6. The heater panel according to claim 5, further comprising a heating circuit comprising a controller, wherein the switch is a protection switch, wherein the controller is operatively connected to the temperature sensor and the protection switch, and wherein the protection switch is operatively connected to the ceramic heating element, and wherein when the temperature sensor detects a temperature above a predetermined point or 100 ℃, the controller signals the protection switch to disconnect the ceramic heating element from the heating circuit.

7. The heater plate according to any one of the preceding claims, further comprising a protective plate secured to the bottom surface, wherein the ceramic heating element and the thermally conductive layer are located between the bottom surface and the protective plate.

8. The heater panel according to any one of the preceding claims, wherein the thermally conductive layer is an adhesive thermally conductive layer; or a thermally conductive silicone sheet, a thermally conductive adhesive, a thermally conductive silicone grease, and combinations thereof; or a thermally conductive silicone sheet, a thermally conductive adhesive, and combinations thereof; or a thermally conductive silicone sheet and a thermally conductive adhesive.

9. The heater panel according to any one of the preceding claims, further comprising a controller and a power source, wherein the controller is operatively connected to each of the temperature sensor, the ceramic heating element and the power source.

10. The heater panel according to any one of the preceding claims, further comprising an additional sensor.

11. The heater plate according to any one of the preceding claims, further comprising an additional component.

12. A humidifier comprising a heater plate according to any preceding claim.

13. A medical device comprising a heater plate according to any one of claims 1-11, or a humidifier according to claim 12.

Technical Field

The present invention relates to heater plates, and more particularly to heater plates for providing humidified air or humidified gas.

Background

Humidifiers are common appliances and devices that provide humidified air or gases. Humidifiers are used in houses, hospitals, etc. and are in various forms. The humidifier may utilize heat or ultrasonic vibration.

Humidifiers and other medical devices therefore typically contain a heater plate that heats to conduct thermal energy to, for example, water or a container containing water, causing the water to evaporate and/or even boil. Typical heater plates contain heating elements, usually electrical heating elements, and more recently ceramic heating elements have become popular and are used, for example, in respiratory humidifiers to assist patients who need to breathe humidified air. See, for example, US 9,821,135B 2 granted to Tang et al on 21/11/2017 and assigned to ResMed, llc.

Heaters, humidifiers, and medical devices typically include various sensors to detect, for example, heater plate temperature, water level in the water reservoir, presence or absence of the water reservoir, humidity of the air, and the like. In many cases, the temperature of the heater plate is measured via indirect contact or by calculating the temperature. However, it has now been found that this method may be inaccurate, with temperature variations up to e.g. 10 ℃.

This temperature change in turn may result in insufficient humidity in the gas, or excessive humidity in the gas. This may also result in the gas being too hot or too cold for the patient. This can also lead to other problems, such as bacterial growth in the water reservoir, and/or drying of the water reservoir as all of the water evaporates from the water reservoir.

Therefore, it is desirable to measure the heater plate temperature more accurately.

Disclosure of Invention

In one embodiment herein, a heater plate for a humidifier includes a thermally conductive plate having a top surface and a bottom surface opposite the top surface. The temperature sensor is secured to the bottom surface, and the thermally conductive layer is directly secured to the bottom surface. The ceramic heating element is directly fixed to the heat conductive layer.

Without being limited by theory, it is believed that the inventors found that previous techniques of indirectly measuring or estimating the temperature of the heater plate were inaccurate and may vary by, for example, 10 ℃. This in turn may lead to excessive energy usage, humidified air that is too hot for the patient, humidified air that is too cold for the patient, humidified air that does not carry enough moisture to be too dry for the patient, humidified air that carries too much moisture, resulting in increased condensation in the breathing circuit and/or a large change in temperature from one minute to the next. In contrast, by fixing the temperature sensor directly to the bottom surface of the heat-conducting plate of the heater plate, and even better, between the ceramic heating elements, it is believed that the present invention can more accurately measure the true temperature of the heater plate, rather than estimate it. This in turn may provide more accurate and timely feedback through the controller/microprocessor of the device. Further, it is believed that the present invention may provide a heater plate having a more evenly distributed heating profile.

Drawings

FIG. 1 shows an inverted exploded view of one embodiment of the heater plate of the present invention;

FIG. 2 shows a top view of the bottom surface of one embodiment of the heater plate of the present invention; and is

FIG. 3 illustrates a schematic diagram of an embodiment of an electrical system useful herein.

The drawings herein are for illustration purposes only and are not necessarily drawn to scale.

Detailed Description

All measurements are made in metric units, unless specifically stated otherwise. Further, all percentages, ratios, and the like herein are by weight unless otherwise specifically indicated.

As used herein, the term "secured to" and variations thereof means that two or more items are directly or indirectly connected to each other as desired. Thus, the term "secured to" and variations thereof include "directly secured to" and "indirectly secured to" without other descriptors.

Embodiments of the present invention are directed to heater plates comprising a thermally conductive plate comprising a top surface and a bottom surface. The bottom surface is opposite the top surface and includes a temperature sensor secured to the bottom surface, a thermally conductive layer secured directly to the bottom surface, and a ceramic heating element secured directly to the thermally conductive layer.

The heater plate may be used to heat water in a water reservoir of, for example, a humidifier/humidification system or a medical device. Humidifiers and humidification systems, as well as medical devices employing heater plates, are well known in the art.

In order to accurately determine the temperature of the heater plate, a temperature sensor is secured to a bottom surface of a thermally conductive plate forming a portion of the heater plate. The temperature sensor may be directly or indirectly secured to the bottom surface of the thermally conductive plate. In one embodiment herein, the temperature sensor is directly affixed to the bottom surface of the thermally conductive plate. Without being limited by theory, it is believed that securing the temperature sensor to the bottom surface, or directly to the bottom surface, allows for better direct measurement of the temperature, rather than via indirect measurement and/or estimation of the temperature. In one embodiment herein, the temperature sensor is located in proximity to the ceramic heating element; alternatively, if there are multiple ceramic heating elements, the temperature sensor may be located between at least two ceramic heating elements; or between multiple ceramic heating elements.

The temperature sensor may generally be of any type known in the art. In one embodiment herein, the temperature sensor herein is selected from the group consisting of a Negative Temperature Coefficient (NTC) sensor, a Positive Temperature Coefficient (PTC) sensor, a platinum resistance temperature sensor, a digital temperature sensor, and combinations thereof, or an NTC sensor. In one embodiment herein, the temperature sensor is a bandgap temperature sensor on an integrated circuit, such as the Sensorion humidity and temperature sensor SHT21 available from https:// www.sensirion.com/en/. Such a temperature sensor is believed to provide good stability and high accuracy in a desired temperature range.

The thermally conductive layer enhances heat transfer between the ceramic heating element and the bottom surface of the thermally conductive plate. Typically, ceramic heating elements are hard but brittle and therefore it is not recommended to make the heater plate and/or the thermally conductive plate itself out of a ceramic material. However, by placing a thermally conductive layer between the bottom surface and the ceramic heating element, contact between these parts is made more complete and heat transfer is also enhanced, while the heater plate and/or the thermally conductive plate protects the ceramic heating element from impact, moisture, etc. In one embodiment herein, the thermally conductive layer is an adhesive layer that helps to seal and ensure that the ceramic heating element is securely fixed to the bottom surface. In one embodiment herein, the thermally conductive layer comprises a thermally conductive silicone sheet, a thermally conductive adhesive, a thermally conductive silicone grease, and combinations thereof; or a thermally conductive silicone sheet, a thermally conductive adhesive, and combinations thereof; or a thermally conductive silicone sheet and a thermally conductive adhesive. Without being limited by theory, it is believed that the thermally conductive silicone sheet may provide an impact absorbing effect, thereby protecting the heating element, especially a ceramic heating element that may be brittle. Without being limited by theory, it is believed that the thermally conductive silicone grease may provide improved heat transfer without becoming rigid and brittle over time.

Ceramic heating elements are known in the art (see Liu, US 4,939,349, issued on 3.7.1990, assigned to Uppermost Electronic Industries, taiwan, high stamen) and may be formed in a variety of shapes and sizes. Such ceramic heating elements are available from a number of manufacturers around the world and may be provided, for example, in strips or plates; or a strip; or a long strip of a series of attributes. In one embodiment herein, the ceramic heating element is effective in a wattage range of about 100W to about 250W. Without being limited by theory, it is believed that the ceramic heating element provides one or more benefits, such as high thermal conductivity, small size, efficient heat generation, and/or long life.

However, as mentioned, ceramic heating elements can be brittle and have low impact resistance. Thus, they are not generally intended to form the top surface of the heater plate and/or the thermally conductive plate that needs to resist impact, dropping, etc. In this way, the ceramic heating element will typically cover only a portion of the bottom surface, thereby also allowing other items, such as, for example, a temperature sensor, to be attached to the bottom surface. In preferred embodiments herein, the ceramic heating element comprises a plurality of ceramic heating elements secured directly or indirectly to the bottom surface of the thermally conductive plate. In one embodiment herein, the ceramic heating elements are evenly arranged at intervals around the bottom surface; or arranged in a ring; or a plurality of concentric rings.

In one embodiment herein, the heater plate comprises a plurality of ceramic heating elements; or from about 2 to about 10 ceramic heating elements; or from about 2 to about 6 ceramic heating elements; or from about 2 to about 4 ceramic heating elements; or about 2 ceramic heating elements. In one embodiment herein, the ceramic heating element is a ribbon; or a thin strip; or a plurality of strips; or in the form of a plurality of thin strips. In one embodiment herein, the strip has at least one face; or from about 1 facet to about 6 facets. Typically, each face is flat, but it should be appreciated that each face may be a different shape, and/or one face may be curved. Without intending to be limited by theory, it is believed that the plurality of heating elements evenly distributed around the bottom surface may provide a more even heat distribution across the heater plate such that the thermally conductive plate will have a more evenly distributed heating profile, which in turn results in a more even evaporation of water. Without intending to be limited by theory, it is believed that an additional benefit of the ceramic heating element in the form of a strip or thin strip is that the ceramic heating element is less likely to crack or break over time or over long heating times due to the relatively small area and thin profile. In one embodiment herein, the temperature sensor is positioned between the plurality of ceramic heating elements, and the temperature sensor and the ceramic heating elements are secured to the thermally conductive plate. Therefore, the temperature sensor directly detects the temperature of the heat conductive plate.

When using a heater plate to heat, for example, water in a water reservoir, it is often important to be able to discern whether the water reservoir is present. Thus, in one embodiment herein, a water reservoir sensor is included herein to detect the presence or absence of a water reservoir, and/or to detect whether a water reservoir is present, properly placed, and/or properly attached. The water reservoir sensor may directly or indirectly prevent the heater plate from activating if the water reservoir is not present, not properly placed, and/or not properly attached by, for example, physically or electrically disconnecting the heater plate's heating element circuit.

Furthermore, to prevent the heater plate from being activated when the water is fully evaporated, it may also be desirable to be able to discern whether there is sufficient water in the water reservoir. Thus, in one embodiment herein, the heater plate further comprises a water level sensor; or a pressure sensitive water level sensor, an optical water level sensor, a water level temperature sensor and combinations thereof; or an optical water level sensor. A pressure sensitive water level sensor may be positioned below the bottom of the heater plate. The pressure sensitive water level sensor may or may not be in physical contact with the heater plate when no water reservoir is placed on the heater plate and/or when there is not sufficient water placed in the water reservoir, as desired. When the water reservoir of minimum weight (i.e., including a minimum amount of water) is placed on the heater plate, the heater plate may then be lowered or dropped in order to physically activate the switch. In one embodiment herein, the switch includes a spring or other device that biases the switch to a particular position and/or prevents the switch from activating unless a predetermined weight (i.e., the water reservoir and water therein) is pressed down on the heater plate.

Alternatively, the optical water level sensor may detect when sufficient water is present to allow activation of the heating element circuit of the heater plate. In another embodiment, the water level temperature sensor may detect whether the temperature of the heater plate and/or the water reservoir is above a predetermined temperature, such as, for example, 100 ℃; or 101 ℃; or 105 c, indicating that there is insufficient water in the water reservoir.

In one embodiment, when the apparatus is such that the water reservoir is present and sufficient water is provided therein, then the heating element circuit of the heater plate is closed and the circuit is complete so that power can flow into the heating element. However, when the device is not satisfied that the water reservoir is present and sufficient water is provided therein, then the heating circuit of the heater plate is open and thus power ceases and cannot flow through the heating element.

In one embodiment herein, to prevent the temperature sensor, the thermally conductive layer and/or the ceramic heating element herein from being removed from the heater plate, a protective plate may be provided. In one embodiment herein, the protective plate is fixed to the bottom surface and thus sandwiches the heat conductive layer and/or the ceramic heating element between the bottom surface and the protective plate. Thus, the heat conductive layer and/or the ceramic heating element is located between the bottom surface and the protective plate. Without intending to be limited by theory, it is believed that the protective plate may also reflect heat from the ceramic heating element back to the heater plate, thereby increasing the thermal efficiency of the heater plate. Without intending to be limited by theory, it is also believed that the thermally conductive layer may also reduce the chance of sparking from a short circuit between the ceramic heating element and the bottom surface of the heater plate. Such as heater plates, humidifiers, medical equipment, etc., may be used in hospitals or other environments where a patient may require higher than normal levels of oxygen, and it is particularly important to avoid sparking and short circuits.

In one embodiment herein, the thermally conductive plate, the protective plate, or both may comprise metal, or aluminum, or steel, or a combination of aluminum and steel, since metal, or aluminum, or steel and/or combinations thereof are considered to be effectively thermally conductive and readily formable into a desired shape. In one embodiment herein, the thermally conductive plate is formed of an aluminum alloy, such as aluminum alloy AA6061 and aluminum alloy AA6063, defined by the aluminum association of arlington, virginia, usa, both of which are available from various suppliers worldwide. Without intending to be limited by theory, it is believed that the aluminum alloy may improve the overall heat transfer efficiency of the heater plate.

In one embodiment herein, the power supply in the humidifier includes a switching power supply that controls the current. Specifically, when a power output of up to about 250W is achieved, the voltage of the heater plate is controlled to about 24V or less. Thereby reducing the chance of electrocution of the user. Without intending to be limited by theory, it is believed that such an electrical shock occurs if the voltage flowing through the heater plate is too large, such as, for example, above about 36V.

Typically, the heater board, humidifier and/or medical device will contain a controller, which may be, for example, a printed circuit board, a microcontroller and/or a combination of software and hardware; or a combination of software and hardware. The controller coordinates various functions, inputs, outputs, etc. of the heater plate, humidifier, and/or medical device. For example, the controller may receive signals from a switch, a tank indicator, and/or a water level sensor to adjust the flow of electricity to the ceramic heating element, i.e., either allow the flow of electricity to the heating element or prevent the flow of electricity to the ceramic heating element. The controller may also receive temperature information, for example from a temperature sensor, to determine and adjust the amount of power that should flow to the ceramic heating element. The controller may further collect and/or process the received data and/or communicate such data to another unit via a wire, portable or permanent storage device, wireless connection, or the like.

Turning to the drawings, FIG. 1 shows an inverted exploded view of one embodiment of the heater plate 1 of the present invention. The heater plate 1, which contains the thermally conductive plate 10, has a top surface 12 and a bottom surface 14 opposite the top surface 12. The bottom surface 14 contains a temperature sensor 16 that is directly secured to the bottom surface 14. The bottom surface 14 also includes a plurality or two thermally conductive layers 18 that are directly secured to the bottom surface 14. A plurality or two of the ceramic heating elements 20 are directly secured to a plurality or two of the thermally conductive layers 18.

In fig. 1, each ceramic heating element 20 contains a pair of electrical contacts 22 that are typically connected (e.g., via wires) directly or indirectly to a controller (see fig. 2, at 42). A protective plate 24 is provided that contains a plurality of cutouts 26 and screw holes 28.

When the protective plate 24 is fixed to the bottom surface 14 via screws 30 and screwed through the screw holes 28, the protective plate 24 covers the ceramic heating elements 20 and the heat conductive layer 18 to protect them from damage and movement. Further, a switch 32 (in this case, a protection switch) is fixed to the bottom surface 14. When the temperature sensor 16 detects that the temperature of the heater plate is too high, a signal may be sent to the controller (see fig. 2, at 42) to cause the protection switch to interrupt the current to the ceramic heating element 20. Alternatively, the switch may be, for example, a pressure sensitive switch or other type of switch, as desired.

Typically screws (not shown) protrude from the cut-outs 26 in the protective plate 24. Wires (not shown) connecting the temperature sensor 16 to the controller (see fig. 2, at 42) and/or connecting the electrical contact 22 to the controller (see fig. 2, at 42) may also protrude from the cutout 26.

In fig. 1, the bottom surface 14 also contains a plurality of grooves 34. Each of the ceramic heating elements 20 is located in and secured to a slot 34 to reduce movement of the ceramic heating elements 20. The slot 34 may have a plurality of faces 36, or about three faces 36. Furthermore, the slot is sized and shaped so that the ceramic heating element fits snugly therein; or three sides of the ceramic heating element contact the faces of the slot. Without intending to be limited by theory, it is believed that in this manner, at least three faces of the ceramic heating element will contact (tough) the edges of the slot, and thus the bottom surface. This in turn increases the direct transfer of heat from the ceramic heating element 20 to the bottom surface 14 and thus to the thermally conductive plate 10 and the heater plate 1.

Fig. 2 shows a top view of the bottom surface 14 of one embodiment of the heater plate 1 of the present invention. The protective plate 24 is attached to the bottom surface 14 of the heat conductive plate 10 by a plurality of screws 30. The electrical contacts 22 can be seen protruding from the cut-outs 26 or passing through (see 22') the protective plate 24. The temperature sensor 16 is attached directly to the bottom surface 14 and is secured in place by screws 30. The temperature sensor 16 is fixed adjacent to the switch 32, which in this case is a protection switch.

Fig. 3 shows a schematic view of an embodiment of an electrical system 40, where the electrical system 40 may be used in a medical device, a humidifier, and/or a thermally conductive plate. Controller 42 is electrically and operatively connected to either or both ceramic heating elements 20 via switch 32, which may be a pressure sensitive switch or a protection switch. The controller 42 is also electrically and operatively connected to the temperature sensor 16, the power source 44, the additional sensor 46, the additional component 48, and the like.

Additional components useful herein include, for example, memory or data storage components, a wireless transceiver for data transfer, a wired connection to another device, a clock, and the like.

Additional sensors 46 useful herein include, for example, a water level sensor 50 (e.g., for detecting whether there is sufficient water in the water reservoir), a water tank detector 52 (e.g., for detecting whether the water reservoir is present and/or whether it is properly attached/secured), an ambient temperature sensor, a humidity sensor, an air flow sensor, an air velocity sensor, a heartbeat sensor, and combinations thereof; or a water level sensor 50, a water tank detector 52, an ambient temperature sensor, a humidity sensor, and combinations thereof; or a water level sensor 50, a water tank detector 52, an ambient temperature sensor, and combinations thereof.

It is to be understood that only examples in which the present invention may be practiced have been shown and described and that modifications and/or changes may be made thereto without departing from the spirit of the invention.

It is also to 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 incorporated herein by reference in their entirety. However, citation or incorporation of such references is not necessarily an admission of their suitability, citation, and/or availability as prior art to the present invention.