AND INCUBATOR SYSTEMS

FIELD OF THE INVENTION

The invention relates to heating and sterilization, in particular to heating and sterilization associated with incubators.

BACKGROUND TO THE INVENTION

Premature and unwell babies are sometimes cared for in incubators which are designed to keep the baby warm, and maintain an atmosphere which is as free of contaminants as possible.

Current incubators suffer from a number of problems. Incubators tend to be made of expensive materials, and require regular maintenance, increasing the costs and making the incubators less accessible and affordable. This is particularly the case in poorer countries.

Maintenance of existing incubators can also be expensive. In developing countries there is sometimes noone who has the expertise necessary to perform even routine maintenance tasks. This leads to expensive incubators being unusable because of routine faults and lack of scheduled preventative maintenance.

Existing incubators also typically include expensive equipment designed to introduce clean air into the incubator.

One of the most significant sources of contaminants in an incubator is the child. Children in incubators are of course weak and/or in poor health. Simply placing a sick child into an incubator introduces a large number of microorganisms. Children suffering from illnesses which result in vomiting or diarrhoea will -regularly reintroduce microorganisms to the incubator.

Adding to this problem, the incubator provides an environment in which microorganisms tend to grow rapidly.

There are systems available which attempt to maintain a sterilized environment, but these can be expensive, bulky, and require regular servicing or replacement.

Measurements and diagnostic tests are often performed on a child away from the incubator, and this requires removal of the child from the incubator for the testing to be carried out. Opening of the incubator and subsequent reintroduction of the child results in recontamination of the incubator.

It is an object of the invention to provide an improved incubator or at least to provide the public with a useful choice.

SUMMARY OF THE INVENTION

In a first aspect the invention provides a sterilization and heating apparatus including: one or more UV light emitting diodes emitting radiation of one or more wavelengths suitable for sterilization of a fluid; and

circuitry arranged to supply power to the UV light emitting diodes;

wherein heat generated in the circuitry as a result of the supply of power to the light emitting diodes is used to heat the fluid.

Preferably the apparatus includes a flow device configured to cause gas to flow through the sterilization and heating apparatus. Preferably the flow device is a fan. Preferably the apparatus includes one or more visible light emitting diodes in addition to the UV light emitting diodes.

Preferably the apparatus includes more UV light emitting diodes than are required to effect sterilization of the air. -

Preferably the apparatus includes a controller configured to turn on and turn off the light emitting diodes so as to control the amount of heat generated in the sterilization and heating apparatus.

Preferably the controller is configured to turn on and turn off one or more groups of the light emitting diodes individually, each group including one or more light emitting diodes.

Preferably the controller is configured to receive a temperature measurement from a temperature sensor and to control the light emitting diodes so as to control the amount of heat generated in the sterilization and heating apparatus to achieve a desired temperature.

Preferably the light emitting diodes and/or circuitry are mounted on a heat conducting bulk material such that heat generated as a result of the supply of power to the light emitting diodes is transferred to the bulk material.

Preferably the light emitting diodes are mounted on a heat conducting bulk material such that heat generated at electrical junctions where the light emitting diodes are connected to the circuitry as a result of the supply of power to the light emitting diodes is transferred to the bulk material. Preferably the bulk material is a heat sink. Preferably the heat sink is made from aluminium. Preferably the heat sink includes two or more fins.

Preferably the light emitting diodes are . mounted on the bulk material using mechanical means. Preferably the mechanical means include at least one fastener. Alternatively the light emitting diodes may be mounted onto the surface using heat conducting glue.

Preferably the apparatus includes a reservoir or conduit for holding or transporting fluid wherein the UV light emitting diodes are arranged to irradiate the reservoir or conduit. Preferably the fluid in the reservoir or conduit is water.

Preferably the apparatus includes a treatment chamber or conduit within which the light emitting diodes are arranged to illuminate at least some of the fluid passing through the chamber or conduit. Preferably the fluid is a gas. Preferably the fluid is air.

In a second aspect the invention provides an incubator including a sterilization and heating apparatus according to the first aspect and an occupancy chamber.

Preferably the incubator includes a functional unit containing the sterilization and heating apparatus, wherein the occupancy chamber is a portable chamber configured to be detached from and reattached to the functional unit.

Preferably the incubator includes or is configured for connection to one or more monitoring devices.

Preferably the monitoring devices , include one or more , of: an occupancy chamber temperature sensor, an occupant temperature sensor and a humidity sensor. Preferably the incubator includes one or more communication ports configured forconnection to one or more external devices.

In a third aspect the invention provides an incubator including:

a functional unit; and

a portable occupancy chamber configured to be connected to the functional unit; wherein the functional unit is configured to regulate and/or monitor the environment within the occupancy chamber when the occupancy chamber is connected to the functional unit, and the occupancy chamber is configured to be detached from and reattached to the functional unit.

Preferably the functional unit is configured to regulate the temperature within the occupancy chamber.

Preferably the incubator includes a temperature sensor and a controller configured to control regulation of the temperature in accordance with readings from the temperature sensor.

Preferably the functional unit is configured to regulate humidity within the occupancy chamber.

Preferably the incubator includes a humidity sensor and a controller configured to control regulation of the humidity in accordance with readings from the humidity sensor.

Preferably the functional unit and the occupancy chamber include flow openings configured to allow flow of gas between the functional, unit and the occupancy chamber when the occupancy chamber is attached to the functional unit. Preferably the incubator includes one or more closures configured to close the flow openings in the occupancy chamber when the occupancy chamber is detached from the functional unit.

Preferably the incubator includes one or more fans configured, when the occupancy chamber is attached to the functional unit, to cause flow of gas from the functional unit to the occupancy chamber and from the occupancy chamber back to the functional unit.

Preferably gas is heated inside the functional unit, such that the gas flowing into the occupancy chamber from the functional unit is warmer than the gas flowing into the functional unit from the occupancy chamber.

Preferably the functional unit is configured for sterilization of the gas flowing through the functional unit.

Preferably the incubator includes a releasable fastening arrangement for releasable attachment of the occupancy chamber to the functional unit.

Preferably the occupancy chamber weighs less than 3.5kg. Preferably the occupancy chamber weighs less than 2.0kg.

Preferably the gas is air.

Preferably the functional unit is positioned underneath the occupancy chamber when the occupancy chamber is attached to the functional unit. Preferably the incubator is configured to be occupied by a human baby. Preferably the baby is a neonatal and/or premature baby.

Preferably the incubator is predominantly made from one or more of: polyethylene; Perspex; polycarbonate; fibreglass; glass; reinforced plastic; carbon fibre; aluminium; and stainless steel.

Preferably the occupancy chamber includes a curved internal surface with surface mounted baffles configured to assist with the circulation of fluid inside the occupancy chamber.

Preferably the occupancy chamber includes carry handles on the exterior surface.

Preferably the incubator includes an external display configured to display information concerning the operation of the incubator or the status of an occupant of the incubator.

Preferably the functional unit includes a heating and sterilization apparatus according to the first aspect.

In a further aspect the invention provides an incubator including:

a recirculation device configured to promote recirculation of gas within the incubator; and

an occupancy chamber having a substantially curved internal surface configured to affect flow of gas from the recirculation device so as to promote circulation of gas within the occupancy chamber before gas returns to the recirculation device. Preferably the incubator includes a sterilization and heating apparatus according to the first aspect, wherein the recirculation device is configured to cause flow of air through the sterilization and heating device.

Preferably the recirculation device includes at least one fan.

Preferably the incubator is configured to be occupied by a human baby. Preferably the baby is a neonatal and/or premature baby.

Preferably the substantially curved surface is a top surface. Preferably the top surface is transparent.

Preferably the substantially curved surface is fitted with one or more surface mounted baffles to disrupt the flow of gas so as to promote circulation of gas within the occupancy chamber.

In another aspect the invention provides an incubator with at least one internal surface at least partly coated with nanoparticulate silver.

Preferably the nanoparticulate silver is colloidal silver.

In a further aspect the invention provides an incubator including:

a sterilization device; and

a recirculation device configured to cause air to flow repeatedly through the sterilization device. BRIEF DESCRIPTION OF THE DRAWINGS

The invention will now be described by way of example only, with reference to the accompanying drawings, in which:

Figure 1 is a perspective view of an incubator according to one embodiment; Figure 2 is a side view of the incubator of Figure 1 ;

Figure 3 shows a heating and sterilization apparatus according to one embodiment;

Figure 4 is a plan view of a bottom surface of the occupancy chamber of the incubator of Figure 1 ;

Figure 5 shows the occupancy chamber and bottom section separated from one another;

Figure 6 is a schematic diagram of an incubator control and monitoring system. DETAILED DESCRIPTION

Figures 1 and 2 show an incubator 100 including an occupancy chamber 1, and a bottom section 2. The occupancy chamber is configured to receive an occupant, generally a human baby. Babies requiring incubation are usually neonatal and/or premature babies.

An occupant may be visible through the top, transparent wall 3 of the chamber 1.

A heating and sterilization apparatus 4 is located in the bottom section 2 of the incubator 100. The position of the heating and sterilization apparatus 4 is shown in Figures 1 and 2, although the heating and sterilization apparatus may not be visible in the assembled incubator 100. The heating and sterilization apparatus 4 is shown in more detail in Figure 3. The heating and sterilization apparatus 4 is configured to heat and sterilize gas as it flows from one end of the apparatus 4 to the other. This gas flow may be caused by one or more flow devices, such as fans 5. At least one of the fans 5 may include a filter (not shown) to filter particulates from the gas passing through the fan.

The fan or fans may cause fluid (generally a gas) to flow through a treatment chamber or conduit 6 defined by walls 7. The walls 7 may be formed with internal mirror surfaces to reflect the UV light within the chamber 6. This may enhance the sterilisation of fluid in the chamber by reflecting and distributing the UV light emitted by the LEDs. The chamber 6 preferably has a volume between 1500 and 3150 cubic centimetres.

The heating and sterilization apparatus 4 includes at least one light emitting diode (LED) with associated circuitry supplying power to the LED or LEDs, and may include heat dissipating components, such as a heat sink. These components may all be located within the chamber 6.

In the embodiment shown, ultraviolet (UV) LEDs 9 are arranged to irradiate some or all of the gas passing through the chamber 6. The UV light emitted by the LEDs is of a wavelength or wavelengths suitable to damage or kill biological contaminants (for example bacteria). It is believed that UV light disrupts the genetic material in such biological contaminants so that the micro organism is no longer able to replicate, removing its ability to multiply and also hastening its death. Wavelengths in the range 280 - 365 nm may be suitable.

The UV LEDs are solid state devices which themselves run cold, as little of the electrical power used in the LEDs is turned into heat. However, at the electrical junctions between the UV LEDs and the rest of the circuitry supplying electrical current to the UV LEDs, a significant amount of heat is generated. The heat generated at these points, and other heat generated within the circuitry, is used to heat the passing gas flow. This is in complete contrast to most devices using LEDs, where the heat generated in the circuitry is an undesirable waste product to be removed from the device.

Gas flowing from the heating and sterilization apparatus passes into the occupancy chamber. The bottom surface 1 1 of the occupancy chamber 1 is shown in Figure 4 and includes a number of flow openings. Inflow openings 12 allow gas to flow into the occupancy chamber 1 while outflow openings 13 allow gas to flow out of the occupancy chamber 1. The fans 5 therefore act as recirculation devices. Gas flows through the heating and sterilization apparatus, up through the inflow openings 12 into the occupancy chamber 1, through the outflow openings 13 out of the occupancy chamber 1 and so returns to the heating and sterilization apparatus 4. As the gas is constantly recirculating, the heating and sterilization device is able to maintain a very low level of active contaminants within the incubator.

Gas flowing into the occupancy chamber after passing through the sterilization and heating device is warmer than when it left the occupancy chamber.

The shape of the incubator may be arranged to promote circulation of gas. This may be achieved by curving the top surface 3 of the occupancy chamber and/or the use of deflecting baffles to disrupt the flow of gas, so gas flow from the bottom section 2 is deflected and caused to circulate within the chamber, before returning to the fan 5. This also provides a more even temperature distribution within the occupancy chamber.

In one embodiment, the number of UV LEDs employed is greater than that required for sterilization of air within the incubator. The excess-number of UV LEDs is used to ensure that enough heat generation capacity is available. In addition, where an excess of relatively cheap LEDs is provided, failure of one or a few LEDs will not affect the ongoing functioning of the apparatus. It is also possible to use some visible LEDs 15 to provide additional heat generation.

The LEDs may be connected to the circuitry in a number of ways, including mechanical connections (for example a mechanical fastener such as a clamp or screw), and/or glue with good heat conductivity and stability (e.g. thermodynamic epoxy glue).

The LEDs may be mounted on a bulk heat conducting material, such as a heat sink 16. The heat sink 16 is preferably aluminium but other suitable materials could be used. In any case the LEDs and associated circuitry are connected to the heat sink such that heat generated at the junctions between the LEDs and the circuitry is transferred to the heat sink 16. Heat is released from the heat sink 16 into gas passing through the heat and sterilization apparatus 4.

The heat sink 16 may have a large surface area exposed to the gas flow passing through the heating and sterilization apparatus. One method of maximising the surface area is to shape the heat sink to include fins 17. In the embodiment shown the fins 17 face upwards, away from the surface on which the LEDs are mounted. The fins together provide a curved top surface.

The heat produced is proportional to the number of LEDs receiving electrical power. A controller 19 (Figure 6) may be employed that is capable of controlling the supply of power to the LEDs 9, to turn the LEDs on and off. Preferably the LEDs 9 are controlled individually, but control of groups of LEDs (with each group including one or more LEDs) may be satisfactory for many applications. By turning the LEDs on and off, the controller controls the heat generated by the electronics and therefore the heat supplied to the heat sink and to the passing fluid. The controller 19 may also control other functions associated with the heating and sterilization apparatus 4. For example, the controller may control the fans (turning on/off, fan speed, fan direction etc).

Cycling the LEDs on and off also increases the useful life of the LEDs. A preprogrammed cycle may be used.

One or more temperature sensors 20 may provide input to the controller 19. Temperature sensors 20 may be positioned near the heating and sterilization apparatus 4, for example to monitor the temperature of fluid flowing into and//or out of the heating and sterilization apparatus 4. Temperature sensors 20 may also be positioned remotely from the apparatus 4. For example, in the incubator 100 of Figure 1 , one or more temperature sensors 20 could be positioned in the occupancy chamber 1 and be used to monitor the temperature of the air in the occupancy chamber 1 and/or the body temperature of an occupant. These temperature readings can be provided to the controller 17 and used to control heat output in accordance with one or more desired temperatures or temperature ranges.

In one embodiment, the controller 19 is a digital device, for example a programmable logic controller (PLC).

The controller 19 may also control other functions associated with the incubator, for example the humidity in the occupancy chamber 1. In this case, the controller 19 controls a humidifier 21 in accordance with information supplied by a humidity sensor 22, which may be positioned in the occupancy chamber 1.

The controller 19 may receive input from other sensors 23 as required, and may control other elements 24 associated with the incubator as required. The controller may record measurements from the various monitoring devices 20, 22, 23. Information may be communicated from the controller to an external device over any suitable communications link, e.g. RS-232, USB or a wireless link. Measurements may include temperature inside the incubator, humidity inside the incubator, body temperature of the incubator occupant, and/or any other desired measurement.

One or more user input devices 25 may be provided, allowing a user to set control parameters or otherwise interact with the controller 19. Control parameters may be stored in memory 26 within or associated with the controller 19.

One or more display devices 27 may also be provided, for display of operational parameters, alerts, monitoring information, occupant status information (e.g. temperature, humidity, pulse rate readings etc) or any other required information. A display device may be attached to the side of the incubator.

In one embodiment, the temperature of the occupancy chamber is set by a user, the user being able to set the required temperature or temperature range on the temperature controller.

In Figure 5, the base section 2 is a functional unit which provides various functions to the assembled incubator, including for example heating and sterilization of air by the apparatus 4. The functional unit may be configured to regulate and/or monitor the occupancy chamber environment and/or operational parameters and/or health parameters of the occupant. In this embodiment the occupancy chamber is formed as a separate, portable unit, allowing the occupancy chamber and its occupant to be moved independently of the functional unit. The occupancy chamber may be provided with carrying handles 29.

This allows measurements or tests (e.g. weighing the baby) to be performed without needing to remove the occupant from the occupancy chamber. The weight of the unoccupied occupancy chamber is known and can be subtracted from the weight of the combined occupancy chamber and occupant. Other measurements, tests and procedures may also be performed without removing the baby from the portable occupancy chamber (e.g. x-rays, phototherapy).

The flow openings 12, 13 may be provided with closures to prevent ingress of air while the portable occupancy chamber is detached from the functional unit 2. The functional unit 2 may include a top plate with openings or conduits communicating with the flow openings or conduits in the occupancy chamber (when attached). The functional unit's openings or conduits may also be provided with suitable closures. The closures may close automatically on detachment of the occupancy chamber from the functional unit, or may be manually closed by a worker.

The occupancy chamber 1 and functional unit 2 may be releasably attached to each other using releasable mechanical attachments, such as latches or an automatic clip system. Alternatively the occupancy chamber may simply sit on the functional unit without a locking arrangement.

In this embodiment the occupancy chamber preferably weighs less than 3.5kg, more preferably less than 2.0kg, so it can easily be carried.

When the occupancy chamber and bottom section are connected, gas flow occurs between the two components as described above. It is also possible to control the humidity in the occupancy chamber by allowing a reservoir of water to be controllably evaporated in the bottom section, so that the gas flow returning to the occupancy chamber is of higher humidity than that leaving the occupancy chamber. Other humidifier systems may also be suitable.

In one embodiment of the invention, the occupancy chamber and bottom section are made from light, durable materials that can be moulded into the desired components. A preferred material is polypropylene, though a wide number of suitable materials are available, including polyethylene, Perspex, polycarbonate, fibreglass, glass, reinforced plastic, carbon fibre, aluminium, and stainless steel.

At least one transparent surface or window is preferably provided to allow viewing of an occupant of the incubator.

In one embodiment, at least one interior surface of the incubator, preferably an interior wall of the ^' occupancy chamber, is coated or impregnated with nanoparticulate or colloidal silver. This assists with maintaining a relatively sterile chamber as silver in this form has anti-microbial properties.

It is possible to use the UV LEDs to sterilize a liquid that is held in a reservoir or is being transported through a conduit near the sterilization and heating device. The reservoir or conduit must be close enough to the LEDs for effective irradiation of the liquid. This is useful, for example, if the liquid is to be controllably evaporated (e.g. evaporation of water for humidification). .Sterilization before evaporation helps to maintain a sterilized atmosphere.

The incubator is suitable for any animal, though it is particularly designed for humans, for example a neonatal or premature human baby. In addition to the recirculation of air described above, it is also necessary to introduce fresh air into the incubator. Around 8 to 10 litres of ambient air per minute may be drawn into the incubator, and this can easily be achieved using an opening in the outside wall of the incubator, preferably with a filter fitted. The filter may be a bioactive filter, such as a filter coated or impregnated with nano-particulate silver. The filter may be formed from a methyl methylacrylate substrate. The filter may also be coated or impregnated with nanoparticulate titanium dioxide, which helps to increase the antimicrobial activity of the silver-coated or impregnated filter.

Inflow of fresh air may be assisted by one or more fans. Alternatively the opening could be situated at a low pressure point (e.g. near the intake of the fan 5) so that ingress of fresh air is promoted by operation of the heating and sterilization apparatus. This has the advantage that fresh air is immediately on entry passed through the heating and sterilization apparatus.

In one embodiment two openings are provided for ingress of fresh air, one at each end of the incubator . Each opening is fitted with a filter and preferably each filter has a grade of EU4 to EU7. The directions of the fans 5 are periodically changed to reverse the direction of air flow. This means that air flows in through a first opening and out through a second opening for a first time period and then in through the second opening and out through the first opening for a second time period. This helps to prevent clogging of the filters, since material collected in the first opening's filter during the first time period will at least to some extent be blown out of the filter during the second time period.

The first and second time periods may be of any suitable duration, and may be of the same or different duration. A continuous cycle where each period is around 20 minutes may be suitable. The occupancy chamber is of course fitted with a suitable mattress. The mattress may be a removable washable moulded mattress, and may be constructed of a synthetic fibre and wool blend. The mattress may be impregnated with nanoparticulate silver and/or gold, which may provide anti-microbial properties.

The occupancy chamber will have suitable openings to allow connection of necessary equipment, such as respirators, IV infusion systems, monitoring equipment and waste systems.

LEDs are extremely long-lasting. The Applicant's heating and sterilization apparatus is therefore a reliable, low maintenance and long-lasting apparatus. In addition, LEDs are an increasingly cheap component. Other components, such as the simple circuitry, controller, heat sink and fans are also readily available cheap components. The apparatus, _, and incubators incorporating such an apparatus, are therefore low cost and reliable and suitable for application across the developed world as well as in poorer countries.

Using the waste heat from operation of the LEDs to warm air in the incubator again reduces cost and complexity. No dedicated heating system is required, reducing cost and maintenance requirements.

The recirculation of air within the incubator means that air is repeatedly exposed to UV light in the sterilization apparatus. This repeated exposure contributes to maintenance of a highly sterile environment within the incubator.

Although described in the context of an incubator, the Applicant's heating and sterilization device has wider applications, particularly in the medical field. The heating and sterilization device could be used in respiratory humidifiers and/or ventilators or in sterilization systems for medical instruments and the like.

While the present invention has been illustrated by the description of the embodiments thereof, and while the embodiments have been described in detail, it is not the intention of the Applicant to restrict or in any way limit the scope of the appended claims to such detail. Additional advantages and modifications will readily appear to those skilled in the art. Therefore, the invention in its broader aspects is not limited to the specific details, representative apparatus and methods, and illustrative examples shown and described. Accordingly, departures may be made from such details without departure from the spirit or scope of the Applicant's general inventive concept.