SE543504C2 - Portable cooling device comprising a Peltier element - Google Patents

Abstract

The present disclosure relates to portable cooling devices (200) for cooling the skin of a live human. The portable cooling device (200) comprises a cooling element (210) thermally coupled to a cooling area (220) of an external surface (230) of the portable cooling device (200). The portable cooling element is arranged to cool the cooling area to a desired temperature interval. The portable cooling device (200) further comprises heat evacuating means (240) arranged to evacuate heat from the cooling element. The portable cooling device (200) also comprises a battery (250) arranged to provide power to the portable cooling device. The portable cooling device (200) additionally comprises control circuitry (260) arranged to control the portable cooling device.

Description

1 Portable cooling device cornprising a Rzštšez' element TECHNICAL FIELD The present disclosure relates to portable cooling devices. ln particular, it relates to portablecooling devices for cooling a predetermined area of a surface in contact with the portable cooling device.

BACKGROUND People suffering from pain, in particular chronic pain, often finds that in addition the sufferingfrom the pain itself, the pain has a detrimental effect on the person's ability function ineveryday life, thereby compounding the suffering. While pain can be somewhat relieved bymedication, there might be side effects from the medication, as well as the apparent risk ofdeveloping an addiction over time. ln the case of chronic pain, one medical alternative is so-called trigger point injections, where tight spots are introduced into a patient to squeezenerves and lead away pain. Another medical alternative, radio frequency ablation, targets thenerves that send pain signals to the brain by burning them with a needle. Other means ofrelieving pain, such as holding ice packs against an aching area or taking a hot shower in caseof back pain, are often impractical or unavailable at the time of need and take up all the focus of the person, thereby still reducing the person's ability to function in everyday life.

People suffering from certain types of mental illness may face similar challenges as peoplesuffering from pain. For instance, some mental health conditions may be relieved bymedication, but putting the person at risk of potential side effects, as well as the risk ofdeveloping an addiction over time. Likewise, attempts to distract oneself from experienceddiscomfort may take the form of different types of self-harm, e.g. over-eating, drinking, drug abuse or direct physical self-harm. 2There thus exists a need in the art for means of reducing suffering from pain, in particularchronic pain, as well as mental suffering without unduly limiting the person in everyday life, while also reducing or eliminating the need for medical treatment.

SUMMARY One object of the present disclosure is to provide a method which seeks to mitigate, alleviate,or eliminate one or more of the above-identified deficiencies in the art and disadvantagessingly or in any combination and to provide a means for distracting a user from a state of painor mental discomfort without any side-effects, and which may be available to the user at all times without unduly limiting the user in everyday life.

The present disclosure proposes a portable cooling device for cooling an area of the skin of alive human. The portable cooling device comprises a cooling element thermally coupled to acooling area of an external surface of the portable cooling device. The cooling element comprises a Peltier cooling device, and is arranged to cool the cooling area to a desired temperature interval. The portable cooling device further comprises heat evacuating meansarranged to evacuate heat from the cooling element. The portable cooling device alsocomprises a battery arranged to provide power to the portable cooling device. The portablecooling device additionally comprises control circuitry arranged to control the portable coolingdevice. The proposed portable cooling device enables a small, lightweight and portable coolingdevice which can be used to provide cooling of a point of choice by bringing the cooling area incontact with the point and allow the cooling area to cool the chosen point. The proposedportable cooling device further enables a portable cooling device having a low profile, i.e.being relatively flat in a direction perpendicular to the cooling area, which is highly desirable ifthe portable cooling device is further arranged to be worn by a user. The portable cooling device may further be implemented with inexpensive components that are readily available.

Aceoral-Eng-to--so-m-e»-aabeats,--tha-coc»Eing--eåe-ment--ae»mprisas--a---Peifs-ier--coo-lära-g--dexfšæer--A Pe ltie rcooling device, also known as Peltier device. Feåtiea" element, Peltier heat pump, solid staterefrigerator or thermoelectric cooler, can be implemented in flat configurations. A Peltier cooling device therefore enables a reduction in a lateral direction of the portable cooling 3device in a direction perpendicular to the cooling area. ln other words, the Peltier coolingdevice enables a reduction of the profile of the portable cooling device. A Peltier coolingdevice also provides great flexibility in shape, thereby enabling a wide range of different conceivable cooling areas.

According to some aspects, the heat evacuating means comprises a fan. A fan is a means ofactive cooling, which enables time-varying heat transport. Active cooling such as a fan typicallyhas a greater capacity to evacuate heat than passive heat evacuating means, which meansthat the total size and profile of the portable cooling device can be reduced with respect toheat evacuating means based on passive cooling. The size reduction typically also implies acorresponding weight reduction, which is of particular interest if the portable cooling device isarranged to be worn on body parts other than the torso. Furthermore, the fan relies on air as its cooling medium, thereby eliminating the need for bringing a dedicated cooling medium.

According to some aspects, the cooling area and the fan are aligned in a first direction, and thefan is arranged to suck in air via an inlet in the first direction and blow out air via an outlet in adirection perpendicular to the first direction. This arrangement reduces the dimension of theportable cooling device along the first direction, while simultaneously providing a maximalamount of air to cool the cooling element and carrying off heat in a direction away from the surface being cooled.

According to some aspects, the portable cooling device further comprises a user interfacearranged to receive an input command and to control the control circuitry to set the desiredtemperature interval based on the input command. The user interface provides a user with ameans to adjust the cooling effect of the portable cooling device. ln particular, the userinterface facilitates embodiments where a user may switch between different cooling schemes.

According to some aspects, the control circuitry further comprises a timer, and the desiredtemperature interval is time-dependent, the time-dependency being arranged to becontrolled by the timer. A time-dependent temperature enables using different coolingschemes. A time-dependent temperature further enables saving power, both with respect to the power consumption of the cooling element and the heat evacuating means. 4According to some aspects, the portable cooling device further comprises a communicationsinterface arranged to transmit data relating to usage of the portable cooling device during apredetermined time period. The data from the communications interface enables externaldiagnostics of the portable cooling device as such, as well as providing information relating touser statistics, which can be used to analyse user behaviour during the predetermined time period.

According to some aspects, the portable cooling device further comprises at least onetemperature sensor arranged to determine a temperature of the portable cooling device. Thetemperature sensor enables safety regulation of the temperature as well as enabling areduction in power consumption. The temperature sensor enables indicating if the coolingarea is in danger of being cooled below the desired temperature interval. The temperaturesensor further enables indicating if the portable cooling device is in danger of becoming toohot. The temperature sensor also enables providing feedback for controlling the cooling element and the heat evacuating means, if power-operated.

According to some aspects, the portable cooling device further comprises fastening meansarranged to fasten the portable cooling device to fixate the cooling area against the skin ofthelive human. The fastening means enables the portable cooling device to be worn by the user,thereby freeing the user from having to manually apply the portable cooling device to cool a desired cooling area on the body of the user.

According to some aspects, the portable cooling device further comprises a plurality of coolingelements, each cooling element being thermally coupled to a respective cooling area on anexternal surface of the portable cooling device, each cooling element being arranged to coolthe respective cooling area to a respective desired temperature interval. The plurality ofcooling elements enables cooling over different areas without having to readjust the positionof the portable cooling device with respect to a user. The plurality of cooling elements furtherenables cooling in different patterns, such as random cooling areas, synchronized coolingareas, or gradients, where a plurality of cooling elements are arranged to cool their respectivecooling areas to different temperatures with respect to each other. A plurality of coolingelements also enables striking a balance between cooling a large area and restricting the power necessary to cool the large area. 5According to some aspects, the heat evacuating means comprises a first material having a firstarea greater than the total area of all cooling areas of the portable cooling device, and athermal conductivity arranged to distribute the heat carried off by the heat evacuating meansover the first area. This provides passive cooling, where the thermal energy of the heat carriedoff is distributed over an area which is large relative to the cooling area, thereby keeping thetemperature of the heat evacuating means below a desired temperature interval. ln otherwords, the first material provides distributed heating of the heat carried off during the concentrated cooling of the cooling area.

BRIEF DESCRIPTION OF THE DRAWINGS Figure 1 is a block diagram of a portable cooling device according to the present disclosure; Figure 2 is a perspective view of a portable cooling device according to the present disclosure; and Figure 3 is a block diagram of a portable cooling device according to the present disclosure.

DETAILED DESCRIPTION Figure 1 is a block diagram of a portable cooling device 100 for cooling an area of the skin of alive human. The inventors have found that skin contact with a cold area on the order of a fewcentimetres or less, depending on the temperature and thermal conductivity of the material incontact with the skin, can provide significant distraction from pain, e.g. chronic pain, and thediscomfort experienced during certain types of mental illness, e.g. discomfort driving a personto cause self-harm. The disclosed portable cooling device 100 is arranged to provide such aneffect, while also having physical attributes that allows a user to be free of the limitations ofthe remedies of the prior art. ln particular, the disclosed portable cooling device may bearranged to have a total weight and dimension that enables a user to carry the portablecooling device 100 around during the day without being hindered. As will be described furtherbelow, different aspects further enable the portable cooling device to operate silently and have a profile, i.e. physical form, which enables the portable cooling device to be worn in 6combination with regular clothing or be implemented as part of regular clothing. The user isthen free to go about everyday life, always with a side-effect free means for distracting from pain.

The portable cooling device 100 comprises a cooling element 110 thermally coupled to acooling area 120 of an external surface 130 of the portable cooling device 100. The coolingarea 120 may be a surface of the cooling element 110 itself or a predetermined area on theexternal surface 130 of the portable cooling device 100 in indirect contact with the coolingelement 110. An example of the latter would be a first material in thermal contact with thecooling element 110 via a first area of the first material and the cooling area 120 being asecond area of the first material. The first material preferably has a thermal conductivitysuitable to act as a heat sink, i.e. high thermal conductivity. Example materials include metalsand ceramics such as Aluminium Nitride, Silicon Carbide, Alumina and Silicon Nitride.According to some aspects, the cooling area comprises a convex surface. The convex surfacefacilitates fixating the cooling area to the area on the user to be cooled. A single coolingelement may also be thermally coupled to a plurality of cooling areas, e.g. by being thermallyconnected to a plurality of thermally conductive materials comprising respective cooling areas,or by comprising a cooling surface partially covered by a thermally isolating mask, the mask defining a plurality of cooling areas on the cooling surface. ë-i cooling element comprises a Peltier cooling device. APeltier cooling device can be manufactured flat, with one side acting as or connectingthermally to the cooling area 120, and thus minimizes the extension in a directionperpendicular to the cooling area 120. This thus enables a considerable reduction in thedimension of the portable cooling device 100 in the same direction. ln other words, a Peltiercooling device enables a reduced profile of the portable cooling device 100. This is veryadvantageous when arranging the portable cooling device 100 to be worn by a user. Arelatively flat portable cooling device can be made to fit with a greater range of everydayclothing, which may at least partially cover the portable cooling device during operational use.A Peltier element further enables a great freedom in the shape and dimension of the coolingarea 120. Peltier elements are typically inexpensive and have no moving parts, thereby eliminating noise, being extremely reliable and not requiring any maintenance. The current running through the Peltier element may be reversed, thereby switching the effect of the 7Peltier element from cooling the cooling area to heating the cooling area. This may be used inschemes where the cooling provided by the cooling element is time-dependent, as will be described further below.

The cooling element 110 is arranged to cool the cooling area 120 to a desired temperatureinterval. The desired temperature interval is preferably cool enough for a cooling effect to beappreciated by a user having the cooling area 120 in contact with the skin of the user, and hotenough to avoid damage to the skin. The desired temperature interval is preferably five totwenty-five degrees centigrade, and even more preferably between ten to twenty degreescentigrade. Temperature intervals between five to 15 degrees centigrade and 15 to twenty-five degrees centigrade are also possible. The portable cooling device 100 is preferablyarranged to ensure that the temperature at the cooling area never drops below a lowestsafety temperature. According to some further aspects, the temperature at the cooling area isallowed to drop below the lowest safety temperature for a predetermined duration. Thesafety temperature thus safeguards against injury due to prolonged exposure to cold, whileallowing temporary application of temperatures below the safety temperature. Since thedesired cooling effect may differ between users, some aspects of the portable cooling device100 are arranged to enable the user to select the desired temperature interval, as will be described further below.

The portable cooling device further comprises control circuitry 160 arranged to control theportable cooling device. According to some aspects, the control circuitry 260 furthercomprises a timer. Also, the desired temperature interval is time-dependent and the time-dependency is arranged to be controlled by the timer. By introducing time-dependence,different temperature application schemes are enabled. For example, the portable coolingdevice may be arranged to apply cooling in a pulsed mode, e.g. cooling for a few seconds andthen waiting for a few seconds, etc. For instance, the pulsed mode may com prise five secondsof cooling followed by five seconds of no cooling. The pulsed mode may comprise ten secondsof cooling followed by ten seconds of no cooling. The pulsed mode may comprise fifteenseconds of cooling followed by fifteen seconds of no cooling, and so on in five secondincrements. ln a preferred embodiment, the pulsed mode comprises thirty seconds of coolingfollowed thirty seconds of no cooling. ln another preferred mode, the pulsed mode comprises sixty seconds of cooling followed sixty seconds of no cooling. The longer durations gives the 8user more time to sense the variations in temperature, potentially providing a greater contrastin the cooling experienced by the user. The durations of the cooling periods and/or theperiods in between the cooling periods may be randomized. According to some aspects, aramping scheme is applied. The time-dependence of the temperature may be coupled withother effects in between periods of cooling. For instance, ie1§~ between the periods of cooling.

The portable cooling device 100 further comprises heat evacuating means 140 arranged toevacuate heat from the cooling element 110. The heat evacuating means 140 prevents theportable cooling device from overheating. The heat evacuating means 140 may provide active cooling, passive cooling or a combination thereof.

According to some aspects, the heat evacuating means 140 comprises a fan. The fan is anexample of active cooling. A fan has an advantage in that it uses air as it cooling medium,thereby eliminating the need to carry around cooling fluids, such as water, to cool the portable cooling device 100.

A fan has a further advantage in that it typically has a flat profile. The fan may therefore bearranged over the cooling element 110 with its axis of rotation perpendicular to the coolingelement 110. The fan is preferably also arranged with its axis of rotation perpendicular to thecooling area 120. ln other words, according to some aspects, the cooling area and the fan arealigned in a first direction F, and the fan is arranged to suck in air in the first direction via an inlet and blow out air in a direction perpendicular to the first direction via an outlet.

This enables a considerable reduction in the extent of the portable cooling device 100 in thedirection perpendicular to the cooling area 120. ln other words, the portable cooling device100 may be arra nged to have a reduced profile. Stated differently, the portable cooling device100 may be thinner than alternative positional arrangements of the fan. This is important for the practical use of the portable cooling device 100, since it enables implementing portable 9cooling devices with physical dimensions that may be worn in combination with everyday clothes. For instance, the portable cooling device may in some cases fit under a regular sleeve.

The heat evacuating means may also be arranged to provide passive cooling. Thus, accordingto some aspects, the heat evacuating means comprises a first material having a first areagreater than the total area of all cooling areas of the portable cooling device, and a thermalconductivity arranged to distribute the heat carried off by the heat evacuating means over thefirst area. The idea is to spread heat carried off when cooling a cooling area over an areawhich is greater than the corresponding cooling area. The rise in temperature of the heatevacuating means 140 will thereby be lower than the corresponding drop in temperature atthe cooling area. The heat evacuating means 140 may further be arranged to be exposed tothe surrounding air, thereby enabling heat to be distributed to the surrounded air for more efficient cooling.

The portable cooling device 100 also comprises a battery 150 arranged to provide power tothe portable cooling device. According to some aspects, the portable cooling device comprisesa plurality of batteries. With a plurality of batteries, the dimension of each battery can bereduced while still providing a predetermined total power. By reducing the dimension of eachbattery, the overall dimension ofthe portable cooling device 100 can be reduced. ln particular,the portable cooling device 100 may be arranged having a more flat profile compared to using a single battery. The battery is preferably rechargeable.

According to some aspects, the portable cooling device 100 further comprises at least onetemperature sensor 180 arranged to determine a temperature of the portable cooling device.The temperature sensor 180 enables improved precision in determining the current coolingtemperature of the cooling element. The temperature sensor further enables determining ifthe temperature in the portable cooling device rises above a highest allowable temperaturethreshold. This may be used to prevent overheating in case the ability of the heat evacuatingmeans 140 to evacuate heat is inhibited. A temperature sensor 180 may further improve thepower efficiency of the portable cooling device 100, e.g. by avoiding unnecessary cooling bythe cooling element 110 or unnecessary work by a power operated heat evacuating means 140.

The control circuitry 160 may comprise any suitable type of computation unit 162, e.g. amicroprocessor, digital signal processor, DSP, field programmable gate array, FPGA, orapplication specific integrated circuit, ASIC, or any other form of circuitry. lt should beappreciated that the processing circuitry 60 need not be provided as a single unit but may be provided as any number of units or circuitry.

The control circuitry 160 may also comprise a memory 164. According to some aspects, thememory may be arranged to store received or transmitted data and/or executable programinstructions. The memory may be any suitable type of computer readable memory and maybe of volatile and/or non-volatile type. According to some aspects, the memory is arranged tostore a set of predetermined time-dependent cooling schemes. According to some furtheraspects, the control circuitry 160 is further arranged to change at least one of the time-dependent cooling schemes based on user feedback. The user feedback may be provideddirectly via a user interface or a communications interface, as described further below, or bedetermined based on user behaviour, e.g. usage statistics. ln other words, program settings may be changed adaptively based on user feedback.

According to some aspects, the portable cooling device further comprises a user interface 170arranged to receive an input command and to control the control circuitry to set the desiredtemperature interval based on the input command. The user interface 170 preferablycomprises an input and output interface. The input interface may be arranged to allow theuser to set the desired temperature interval and/or program a time-dependent coolingscheme. According to some aspects, the portable cooling device 100 comprises a set ofpredetermined time-dependent cooling schemes, e.g. stored in the memory 164, and theinput interface is arranged to enable the user to select a cooling scheme from the set ofpredetermined time-dependent cooling schemes. The output interface may comprise one ormore light-emitting diodes, LEDs, arranged to indicate a selected cooling scheme. Such anoutput interface requires very little power and is a preferable option if the portable coolingdevice 100 is optimized for low power consumption. The output interface may also comprise aliquid crystal display, LCD, which can be arranged to display any type of 2D-information, e.g. text and numbers. 11According to some aspects, the portable cooling device further comprises a communicationsinterface 175 arranged to transmit data relating to usage ofthe portable cooling device duringa predetermined time period. The data from the communications interface 175 enablesexternal diagnostics of the portable cooling device as such, as well as providing informationrelating to user statistics, which can be used to analyse user behaviour during thepredetermined time period. According to some further aspects, the communications interfaceis further arranged to receive control signals and/or computer program code. ln other words,the communications interface enables diagnostics and control of the portable cooling device100 via an external device. The communications interface 175 may be arranged to use anycombination of wireless and wired transmission. For instance, according to some furtheraspects, the communications interface is arranged to communicate using Bluetooth. Accordingto some aspects, the communications interface comprises a USB port and/or a micro USB port.According to some further aspects, the USB/micro USB ports may be used to charge thebatteries of the portable cooling device. The data relating to usage of the portable coolingdevice 100 may be obtained from e.g. a memory 164 of the control circuitry 160 or directly from the control circuitry 160 and/or sensors ofthe portable cooling device.

According to some aspects, the portable cooling device 100 further comprises fastening means190 arranged to fasten the portable cooling device 100 to fixate the cooling area against theskin of the live human. The fastening means 190 frees up the user even during operational useof the portable cooling device 100. The fastening means 190 is arranged to maintain thecooling area against the point on the body that the user wants to cool. The fastening means190 may comprise a watchband arranged to enable fastening the portable cooling deviceabout an object having a diameter determined by the watchband, e.g. a wrist of a user. Thefastening means may comprise at least one elastic band arranged to fasten the portablecooling device to the body of a user. According to some aspects, the fastening meanscomprises a piece of clothing, wherein the components of the portable cooling device arearranged at the piece of clothing. For instance, piece of clothing may be a sweater or a jacket on which the other components ofthe portable cooling device are arranged.

Pieces of clothing may be used advantageously to distribute a plurality of cooling elements tobe brought in contact with the user at a corresponding plurality of points on the body. Pieces of clothing may also be used advantageously in combination with passive cooling, since the 12passive heat evacuating means may be distributed over the piece of clothing. Thus, accordingto some aspects, the portable cooling device 100 further comprises a plurality of coolingelements, each cooling element being thermally coupled to a respective cooling area on anexternal surface of the portable cooling device, each cooling element being arranged to coolthe respective cooling area to a respective desired temperature interval. The plurality ofcooling elements may be arranged adjacent to each other in order to define a joint coolingarea. The portable cooling device may comprise either a respective heat evacuating means foreach cooling element, e.g. a fan for each cooling element, or comprise a passive heatevacuating means, or any combination thereof. A respective passive heat evacuating meansmay be arranged for each cooling element, or a plurality of cooling elements may be arranged to share a common heat evacuating means.

Figure 2 is a perspective view of a portable cooling device 200 according to the presentdisclosure. The illustrated portable cooling device is an example of an embodiment suitablefor attachment to an arm of a user. The components of the portable cooling device 200 arechosen and arranged to provide a power-efficient, light and compact portable cooling device.The portable cooling device 200 comprises a Peltier cooling device 210 thermally coupled to acooling area 220 of an external surface of the portable cooling device 200. The coolingelement 220 is arranged to cool the cooling area to a desired temperature interval. Accordingto some aspects, the cooling area comprises a convex surface. The convex surface facilitatesfixate the cooling area against the skin of the live human. The apex of the convex surface islikely to remain in contact with the skin of the human even if the limb to which the coolingdevice is engaged moves slightly with respect to the cooling device. The portable coolingdevice further comprises a fan 240 arranged to evacuate heat from the Peltier cooling device210. The cooling area 220 and the fan 240 are aligned in a first direction F, and wherein thefan is arranged to suck in air in the first direction via an inlet and blow out air in a directionperpendicular to the first direction via an outlet. The orientation of the fan 240 and thealignment of the fan 240 and the cooling area 220 minimizes the necessary extension of theportable cooling device along the first direction F. Keeping the portable cooling device as flatas possible in the first direction increases the probability that the portable cooling device 200will fit, at least partially, in the sleeves of everyday clothing. By stacking the fan on top of the Peltier element, optimal active cooling is achieved, while simultaneously diverting the hot air 13carried off by the fan in directions perpendicular to the first direction. ln other words, the hotair will be directed away from the arm of the user during operational use of the portable cooling device 200.

The portable cooling device also comprises a pair of batteries 250a, 250b arranged to providepower to the portable cooling device 200. The batteries 250a, 250b are preferablyrechargeable batteries. By splitting up the power storage over several batteries instead ofusing a single battery, smaller batteries can be used. Smaller batteries imply that theextension ofthe portable cooling device in the first direction can be reduced by spreading out the batteries in a plane, perpendicular to the first direction.

The portable cooling device 200 further comprises control circuitry 260 arranged to controlthe portable cooling device. The control circuitry 260 preferably comprises a processingcircuitry 262, e.g. a microcontroller board and possibly also a microcontroller shield, and amemory 264. The memory 264 is arranged to store a set of predetermined time-dependentcooling schemes. The memory 264 is preferably also arranged to store data relating to usageof the portable cooling device. The data relating to usage of the portable cooling device maycomprise at least one of diagnostics of the portable cooling device, logging of user activity andanalysis of the user activity. The memory is preferable also arranged to store sensor data from any sensor, e.g. a temperature sensor 280, ofthe portable cooling device.

The portable cooling device 200 also comprises a user interface 270. The user interface 270comprises an input interface comprising a set of buttons 271a, 271b. The set of buttons 271a,271b are arranged to select a cooling scheme from the set of predetermined time-dependentcooling schemes in the memory 264 based on user input via the buttons. The control circuitry260 is further arranged to have the portable cooling device execute the selected coolingscheme. ln other words, the portable cooling device 200 also comprises a user interface 270arranged to receive an input command and to control the control circuitry to set the desired temperature interval based on the input command.

Information regarding the selected cooling scheme is provided by means of an outputinterface comprising a set of light-emitting diodes, LEDs 272a, 272b. The set of LEDs 272a,272b are arranged to provide colour information based on the selected cooling scheme. The simple input and output interfaces thereby reduces the amount of skill required by a user to 14operate the portable cooling device. The input and output interfaces are very energy-efficientchoices, both requiring a minimal amount of power to operate. The input interface preferably also comprises a switch 271c arranged to power on and power offthe portable cooling device.

The portable cooling device 200 preferable comprises a shell 274 arranged to protect thecomponents of the portable cooling device 200 and to provide an optimal airflow for the fan240. ln particular, the shell 274 comprises an inlet arranged to enable inflow of cool air to thefan 240, and an outlet arranged to enable outflow of hot air from the fan 240. The shell 274comprises a transparent or semi-transparent window 273 arranged to enable a user to see theinformation displayed from the output interface. The shell 274 preferably comprises a bio- degradable material.

According to some aspects, the portable cooling device 200 further comprises at least onetemperature sensor 280 arranged to determine a temperature of the portable cooling device.The at least one temperature sensor 280 enables improved temperature control at both thecooling area 220 and inside the portable cooling device. ln other words, according to someaspects, the portable cooling device 200 comprises a temperature sensor arranged todetermine a temperature of the cooling area and to provide the temperature of the coolingarea to the control circuitry 260. The control circuitry 260 may use the determinedtemperature of the cooling area to ensure that the cooling area is cooled to the desiredtemperature interval. According to some aspect, the portable cooling device 200 comprises atemperature sensor arranged to determine a temperature inside the cooling device and toprovide the temperature inside the cooling device to the control circuitry 260. The controlcircuitry 260 may use the determined temperature of the temperature inside the coolingdevice to prevent the cooling device from overheating by adjusting the amount of heat beingevacuated by the heat evacuating means, i.e. increasing the fan speed. According to someaspects, the control circuitry 260 is further arranged to adjust the fan speed based on thetemperature inside the portable cooling device. By varying the fan speed based on the actualneed to remove hot air instead of, e.g., running at a constant fan speed, power consumption can potentially be reduced.

According to some aspects, the portable cooling device 200 further comprises a communications interface arranged to transmit data relating to usage of the portable cooling device during a predetermined time period. The communications interface comprises a USBport and/or a micro USB port 275a. The USB port/micro USB port is arranged to provide powerto the batteries when connected to a power source. The provided power may be used torecharge the batteries 250a, 250b. The USB port/micro USB port is also arranged to transmitdata relating to usage of the portable cooling device during a predetermined time period. Thetransmitted data may be taken from the memory 264 and/or directly from the controlcircuitry 260 and sensors of the portable cooling device. The USB port/micro USB port isfurther arranged to receive control information relating to control of the portable coolingdevice and provide the control information to the control circuitry 260. The controlinformation may comprise control signals and/or computer program code for controlling theportable cooling device 200. For instance, the control information may comprise an updatedset of time-dependent schemes. The control information may also comprise updated driversfor the hardware of the portable cooling device. According to some aspects, the computerprogram code is arranged to perform at least one of diagnostics of the portable cooling device,logging of user activity and analysis of the user activity. According to some further aspects, theportable cooling device is further arranged to transmit information relating to the at least oneof diagnostics of the portable cooling device, logging of user activity and analysis of the useractivity via the communications interface. The communications interface also comprises awireless communications interface 275b, e.g. a Bluetooth interface, a Wi-Fi interface or aninfrared, IR, interface, arranged to perform all the operations of transmitting and receiving information associated with the USB port/micro USB port.

The portable cooling device 200 preferably comprises an attachment band, e.g. a watchbandor an elastic band, arranged to enable fastening the portable cooling device about an objecthaving a diameter determined by the watchband, such as a wrist of a user. ln particular, the attachment band is arranged to fixate the cooling area against the skin ofthe user.

Figure 3 is a block diagram of a portable cooling device according to the present disclosure.Figure 3 illustrates an embodiment of a portable cooling device 300 where the heat generatedby the cooling element is carried off using passive cooling. The portable cooling device 300comprises a plurality of cooling elements 310a, 310b, 310c, 310d, 310e, 310f thermally coupled to a respective cooling area of an external surface of the portable cooling device 300. 16 Each cooling element :gofnprises a Peâtíer cooling alex/ice anti is arranged to cool the respective cooling area to a desired temperature interval. The portable cooling device also comprises atleast one battery 350, preferable rechargeable, arranged to provide power to the portablecooling device. The portable cooling device 300 further comprises heat evacuating means340a, 340b, 340c arranged to evacuate heat from the cooling elements. The portable coolingdevice comprises fastening means arranged to fasten the portable cooling device to the bodyof a user in the form of an article of clothing. The idea is to provide a material having a highthermal conductivity to effectively distribute the heat carried off from the cooling elementssuch that the thermal energy is distributed over a larger area than the total areas of thecooling elements. The temperature increase per unit area of the passive heat evacuatingmeans 340a, 340b, 340c therefore increases less than the temperature decreases at thecooling areas of the respective cooling elements. ln other words, the heat evacuating means340a, 340b, 340c comprise a first material having a first area greater than the total area of allcooling areas of the portable cooling device, and a thermal conductivity arranged to distributethe heat carried off by the heat evacuating means over the first area. The plurality of coolingelements may be coordinated to fire in synchronized cooling schemes, e.g. by creatingtemperature gradients or cooling different parts of the user at different times. The latter may be performed either randomly or in a synchronized manner.

Claims (1)

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1. A portable cooling device (100, 200, 300) for providing a distraction by cooling an area ofthe skin of a live human, the portable cooling device (100, 200, 300) comprising - a cooling element (110, 210, 310a, 310b, 310c, 310d, 310e, 310f) arranged to cool acooling area (120, 220) of an external surface (130, 230) of the portable coolingdevice (100, 200, 300) to a desired temperature interval, - heat evacuating means (140, 240, 340a, 340b, 340c) arranged to evacuate heatfrom the cooling element (ïlgïü 21,0. 3109: 310b, Ésíïšc 310d, fšiífše 310f), - a battery (150, 250, 350) arranged to provide power to the portable coolingdeviCQÅÅQQ¿__Z_QQ._ÃQQE, and- control circuitry (160, 260) arranged to control the portable coolingdevice (100. 200 300), characterized in that the cooling element (110, 210, 310a, 310b, 310c, 310d, 310e, 310f) is in contact withthe cooling area (120, 220), the cooling element (110, 210, 310a, 310b, 310c, 310d, 310e, 310f) comprises a Peltiercooling device, the control circuitry (160, 260) is configured to carry out time-dependent coolingschemes for providing a distraction by cooling an area of the skin ofthe user, and at least one time-dependent cooling scheme is pulsed, whereby the coolingarea (120, 220) is repeatedly cooled for at least 5 seconds and not cooled for at least 5 seconds. The portable cooling device according to claim 1, wherein the heat evacuating means (1110. 240 31102: 340%: 340c) comprises a fan. The portable cooling device according to claim 2, wherein the cooling area__(_l__2_å_)_,___;2__2§}“and the fan are aligned in a first direction (F), and wherein the fan is arranged to suckin air in the first direction via an inlet and blow out air in a direction perpendicular to the first direction via an outlet. lzo The portable cooling device according to any of the preceding claims, further comprising - a user interface (170, 270) arranged to receive an input command and to controlthe control circuitry__§;gi§§},__,2_f;§_Q}_ to set the desired temperature interval based on the input command. The portable cooling device according to any of the preceding claims, wherein thecontrol circuitry (160, 260) further comprises a timer, and wherein the desiredtemperature interval is time-dependent, the time-dependency being arranged to be controlled by the timer. The portable cooling device according to any of the preceding claims, furthercomprising a communications interface (175, 275a, 275b) arranged to transmit datarelating to usage of the portable cooling device ÜÜÜ 200 300§ during a predetermined time period. The portable cooling device according to any of the preceding claims, furthercomprising at least one temperature sensor (180, 280) arranged to determine a temperature ofthe portable cooling device ílâëïš! 200! fåüïši. The portable cooling device according to any of the preceding claims, furthercomprising fastening means (190, 290) arranged to fasten the portable coolingdevice (100 200. 30íí§ to fixate the cooling area g'l20 22.0; against the skin of the live human. The portable cooling device according to any of the preceding claims, further comprising a plurality of cooling elementsíílü. 210 Tšlüa. 31%, šïíšfg, äíüd šïíje, šïíåfi, each cooling elementílíí), 23.0. šífia, šífib ßïlüc.. šlíšd. Eíüe ßïlüf) being arranged to cool a respective cooling area (1202 220§ on an external surface iïšfií 230)of the portable cooling device__{_1Q_QÅ___§QQL__§_QQ1 to a respective desired temperature interval. 10. The portable cooling device according to any of the preceding claims, wherein the heatevacuating means (149, 249, 349211, 34% 34061 comprises a first material having a firstarea greater than the total area of all cooling areas líšü. 2393 of the portable coolingdevicellüü, âüü äíiíïg, and a thermal conductivity arranged to distribute the heat evacuated by the heat evacuating means (lll-G, 240, 3119:12 340%, šflficl over the first area.