FI20205446A1 - Temperature controlled coldness storage of a low-temperature device and a low-temperature device using the same - Google Patents

Abstract

The present disclosure concerns embodiments of an invention directed to an active coldness source of a low-temperature device. An embodied active coldness source comprises one or more modules, each comprising a storage mass of coldness storing substance, to store coldness energy. Coldness storing substance in said one or more modules is arranged to store coldness in a storing mode of the active coldness source. During the storing mode, the active coldness source is cooled into a phase transition temperature, or a further lower temperature, of the storing substance in said one or more modules, to store and/or release the stored coldness during a phase transition of the storing substance. The present disclosure concerns also a hosting low-temperature device using such active coldness source.

Description

TEMPERATURE CONTROLLED COLDNESS STORAGE OF A LOW- TEMPERATURE DEVICE AND A LOW-TEMPERATURE DEVICE USING THE SAME

FIELD OF THE INVENTION Ina general level, the embodiments of the present invention in this disclosure relate to a temperature control of a low-temperature device. In particular, the present in- vention pertains to such temperature control of low-temperature devices in excep- tional conditions, especially such as external loss of power, to preserve the articles being stored inside the low-temperature device in an acceptable storage tempera- — ture.

BACKGROUND A power loss situation in a low-temperature apparatus, such as refrigeration appa- ratus, leads to temperature rise in the interior parts of the volume of the apparatus after a certain time from the power loss event occurrence. If the external power would be lost for a longer time, say longer than an hour, for example, articles such as the foodstuff packages, medical substances, chemicals and/or other biological materials packaged inside, are in danger to deteriorate when getting warm. If not kept in cold, preserving their state steady in correct temperature may lead biologi- cal and/or chemical decomposition, when their temperatures start to rise.

Continuing power loss finally leads defrosting (or melting, where applicable) of the stored goods and articles, if not kept in appropriate temperature, if the external power would not be back in time to re-start the refrigeration process to maintain o the coldness in correct temperature Some mitigation is provided by the coldness O of the parts of the low-temperature device which can make a delay before the tem- + 25 perature starts to rise, but it might be short and not sufficient, for longer power loss = events.

O I Such parts comprise shelves, walls, ceilings and other cold interior structures as - such, which can store the coldness so that the temperature can be maintained for a S while, the temperature-increasing rate being determined by the operating temper- S 30 ature as well as the insulations.

S However, in such an event the temperature is the temperature where the articles were at the moment when the power loss occurred, or, if a break up of a component in the refrigerating system occurred, to prevent the normal operation of the low-

temperature device according to the refrigeration process. The temperature starts to increase, leading after some time to that the stored articles are getting warmer in the storing volume, and if warming continued too long, the temperature sensitive articles would be deteriorated beyond their use.

There are known solutions that are aiming to provide improvement to the above- cited scenario, to solve the problem of how to prevent the stored articles getting warmer when the refrigeration apparatus does not provide the cooling action for the sufficient coldness for the preservation of the articles stored in the refrigerator apparatus in appropriate temperatures. These solutions often rely on passive stor- ing of the coldness into the internal refrigerator’s parts or passive extensions of such. In such a refrigeration system using passive extensions, the same refrigerating ap- paratus follow the same process that refrigerates the storage volume of the low- temperature device, so accumulating coldness to the structures as well as to the passive extension. However, such passive extension may be not effective in long continued power loss events, and would occupy volume from storage capacity. Accumulating coldness should be understood in this disclosure so that, when re- moving the thermal energy of a volume or body so accumulating coldness, it refers to thermal energy removal from said volume or body, to an outside location of — such. For a refrigerator’ interior or its body in question, to a heat dissipation area or a hot spot, normally being arranged outside of the low temperature device. FIG 1 schematically illustrates an ordinary low-temperature device 100, as a fridge. The fridge comprises an evaporator 101, into which the refrigerant is about to be directed in pressurized liquid condition through an expansion valve, for evap- oration and consequential cooling, to maintain the cooling process with the circu- N lating refrigerant, circulation being maintained a motor and a compressor. 4 The refrigerant is in thermal communication, with the cold parts in the storing vol- = ume 103, but also with the dissipation area 106 at the back where the collected 2 heat is transported by the refrigerant circulation. The dissipation area 106 was = 30 — drawn broader than the fridge’s 100 chassis as such for illustrative reasons. S The item 102 comprises a compressor with a motor to maintain the refrigerant’s S circulation and the pressure in the refrigerant line, to circulate the refrigerant to the I dissipation area 106. The fridge 100 has illustrated with some thermal insulation 105 as illustrated by the dashed line in FIG 1. The horizontal lines in the storing — volume 103 illustrate shelves. On one shelf, there is shown a bottle shaped article 104 in the storing volume, to demonstrate such an article that has to be kept in certain article specific cold temperature, in the example below 10 centigrades, for preserving its content fresh/utilizable.

In FIG 1 there is also indicated an optional passive coldness accumulator 107, that is used in the fridge 100 for storing coldness into the passive accumulator 107 — during the operation of the fridge, so to smoothen the temperature raise at the power cut-off situations.

The cooling of the passive element 107 occurs during an active mode of the refrig- eration process of the fridge 100, as the passive element were one of the articles preserved there inside.

However, in many cases it is not necessary to keep the process on all the time. Especially in many cases of foodstuff and/or medical and/or chemical storing fa- cilities, it is sufficient to achieve a certain temperature and then go into an off cycle, during which the temperature may raise slightly, but a thermostat as trig- gered switches the process back to active cooling state when a pre-set temperature — limit achieved, according to certain tolerances. Such procedure saves energy if compared to continuous operation.

Ata power loss situation the refrigeration process stops, and the temperature starts to raise, as there is no further cooling available. There is no cooling, even if a mechanical thermostat would switch the process on, but it would not start, as there 1s no external power in such an event available.

If the power-down situation would be short for the fridge, the temperature would keep in acceptable level, during time scales of minutes to few hours, dependently on the insulation and the thermal conductivity of the insulations (Fig 1, 105). How- ever, the significance of the passive extension 107 is dependent on the thermal iso- o 25 lation, but also on the outside temperature, as well as the articles themselves being O stored in the refrigerator’s storing volume 103 (Fig 1). 3 Similar drawback would be met also when the refrigerator is getting fault and/or = is about to be transported, without external power source. In passive refrigerator I systems, the internal thermal conduction is neglible from a cold charging device - 30 to the interior of the storage volume of the refrigerator. Convection flow is neglible S as the temperature differences are small between the charger and the storage vol- S ume. The coldness is maintained because of insulation, but the thermal energy flux I outside to inside through the insulation warms the interior of the storing volume. It may be not possible to extend the isolation in practice to arbitrarily thick layers, without sever influence to the weight and/or dimensions and consequential utiliza- bility.

SUMMARY In low-temperature devices, their cold parts exchange thermal energy with the en- vironment outside, from which thermal energy is directed to the low-temperature device’s interior parts through the chassis and the thermal insulation, warming the interior parts slowly.

In addition, the interior parts of the low-temperature device are in thermal communication via a heat exchanger with refrigerant circulating in the heat exchanger in a refrigeration process, the refrigerant transporting thermal energy to dissipating areas outside the low-temperature device.

In the disclosure of embodiments of the invention, words coldness and/or coldness — energy are used to denote to the thermal energy, corresponding a thermal energy being transported away by the refrigeration process from the interior parts of the low-temperature device.

In certain sense, the coldness so corresponds an amount of thermal energy being taken away from a certain part of the low-temperature device, and if desired, should be brought back to restore the original temperature — of the certain part.

Consequently a skilled person knows that coldness is related to certain lack of thermal energy in a similar manner as in a domestic household in a fridge, where there is cold inside the fridge, when in operation, the thermal energy being removed to the warmer dissipation area outside the fridge.

In the present disclosure, coldness is similar way considered as a missing energy from a system or body, the energy being removed to somewhere else so that the temperature of said system or body so that without the missing energy (as in certain meaning as negative energy or removed thermal energy) the system or body is correspondingly in a lower temperature than if the missing energy were present without its removal.

Itisan objective of the embodiments of the invention in accordance of the present N disclosure, to at least alleviate the problems described hereinabove not satisfacto- 5 rily being solved yet. = It is an aspect of the objective to provide a feasible protection for preserving the 2 stored articles in storing volumes of low-temperature devices, in reguired temper- = 30 atures during a safeguard period of time.

S It is an aspect of the objective to provide a solution to preserve the temperature S despite of the temporary stop of refrigeration process of the refrigerating apparatus, I even because of mal-functioning and/or a power-loss condition.

The aforesaid objective is achieved by the embodiments of an active coldness source and low-temperature device using such an embodied active coldness source, in accordance with the present embodiments of the disclosure.

The previously mentioned objective(s) are achieved according to the disclosure of 5 the embodiments of the invention as claimed in independent claims directed to an active coldness source and low-temperature devices when using such active cold- ness source according to embodiments of the disclosure An active coldness source of a low-temperature device is characterized in that, the active coldness source comprises one or more modules, each comprising a storage mass of coldness storing substance to store coldness energy into the storage mass of the coldness storing substance in said one or more modules, during storing mode of the active coldness source, the active coldness source during which being cooled into a phase transition temperature, or a further lower temperature, of the storing substance in said one or more modules.

— According to an embodiment, the storing mode of the embodied active coldness source is pre-set to occur simultaneous with active operation mode of the hosting low-temperature device.

According to an embodiment, the active coldness source is an active coldness source of a low temperature device that has a closable cabinet to define a storage — volume for articles and substances to be preserved in a low temperature, by the active coldness source during a power loss event of the low-temperature device. According to an embodiment of the present disclosure, in combination with one or more embodiments, the active coldness source comprises masses of the storing substance in said one or more modules being selected to correspond by the latent o 25 heat of phase transition of said storing substance to provide the coldness being O stored into the mass of said storing substance in a pre-determined safeguard tem- + perature, the corresponding energy of the latent heat of the storing substance’s = mass, providing a preset safe guard temperature during the safeguard period of 2 time as based on the latent heat of the phase transition of the storing substance in = 30 the storage mass.

S According to an embodiment, the composition of the storing substance is selected S to correspond a phase transition to occur with the composition specific latent heat I in the phase transition temperature, corresponding a planned safeguard tempera- ture, during the phase transition.

According to an embodiment, the safeguard time has maximum value determined by the time needed to the phase transition of the storing substance in the storage mass complete.

According to an embodiment of the active coldness source, according to the pre- sent disclosure in combination with one or more embodiments, it comprises such a storage mass of the storing substance in the active coldness source that is pro- portional to a number of the one or more modules of said storing substance.

According to an embodiment variant of such, the modules are modularly attacha- ble/detachable from the active coldness source.

— According to an embodiment variant of such, the number of such modules is de- pendent on the size of the low-temperature device.

According to an embodiment variant of such, the composition of the storing sub- stance is selected according to the safeguard temperature and/or the safeguard time desired.

— According to an embodiment of the present disclosure, in combination with one or more embodiments, the active coldness source comprises such a composition of the storing substance that comprises water in the storing substance to form a part of the storage mass of the one or more modules, to determine the phase transition temperature of the storing substance by the water abundance in said storage mass of the one or more modules.

According to an embodiment of the present disclosure, in combination with one or more embodiments, the active coldness source comprises in the composition of the storing substance, in addition to water, a phase-transition-temperature-lowering agent, to provide a pre-set phase transition temperature of the storing substance for S 25 the one or more modules, to a lower temperature than the water-ice phase transition N temperature in an ambient pressure.

+ <Q According to an embodiment of the present disclosure, in combination with one or a more embodiments, the active coldness source is configured to provide for a pre- E determined hosting low-temperature device a safeguard period of time being pre- © 30 — set to correspond the storing substance’s storage mass bound latent heat.

+ D According to an embodiment of the present disclosure, in combination with one or S more embodiments, the active coldness source comprises at least one fan arranged to circulate air of a cabinet of the hosting low-temperature device, from the cabinet interior, the air being conducted at least partly into thermal communication via said storing substance in said one or more modules. The modules’ casing operating as the thermal communication media.

According to an embodiment of the active coldness source, according to the pre- sent disclosure in combination with one or more embodiments, the air circulation 1s directed to the one or more modules via an airflow channel part leading to/from a evaporator of the low-temperature device at least during storage mode of the active coldness source to store coldness to one or more of said modules.

According to an embodiment of the present disclosure, in combination with one or more embodiments, the active coldness source comprises a dedicated coldness charger in the active coldness source to charge the coldness to the storing substance via a thermal communication. According to an embodiment variant, the dedicated coldness charger is directly connectable by a connector to the refrigeration de- vice’s refrigerant circulation.

According to an embodiment of the active coldness source, according to the pre- — sent disclosure in combination with one or more embodiments, the storing sub- stance comprises a liquid composition to form a latent heat based coldness storing mass, in the phase transition at the freezing point of the storing substance, to store or release said latent energy at the freezing point temperature according to the mode of said active coldness source.

According to an embodiment of the active coldness source, according to the pre- sent disclosure in combination with one or more embodiments, the active coldness source comprises a control module to detect power loss and/or a temperature threshold in the cabinet’s storing volume interior as an initiative being met for triggering a response as a counter measure to at least one of said initiatives.

o 25 According to an embodiment variant, the control module comprises a thermostat O arranged to switch on/off at least one fan to circulate air being conducted through + the active coldness source. According to an optional embodiment, the control mod- = ule is a thermostat. = According to an embodiment of the active coldness source, according to the pre- + 30 sent disclosure in combination with one or more embodiments, the counter S measures comprise to activate the active coldness source into active state to release S coldness with help of a fan produced air circulation, the coldness originating from I the phase transition of the storing substance, proportionally to the latent heat of said storing substance in said one or more modules. According to an embodiment — variant, thereleasing is implemented by an airflow constituted by one or more fans.

According to an embodiment of the active coldness source, according to the pre- sent disclosure in combination with one or more embodiments, the release is im- plemented by an airflow maintained by a battery operable fan, the flow being con- ducted to flow in thermal communication with the storing substance in the active coldness source.

According to an embodiment of the active coldness source, according to the pre- sent disclosure in combination with one or more embodiments, the active coldness source comprises at least one of - a first thermostat configured to control the operation of the coldness charger active when storing coldness into the storing substance, and - a second thermostat in the control logic, configured to control the operation of the dedicated coldness charger into release mode when releasing coldness from the storing substance as a counter measure to at least one initiative. According to an embodiment variant, the active coldness source has redundant thermostats to trigger switching at the same temperature threshold.

A refrigeration device according to an embodiment of the present disclosure in combination with one or more embodiments comprises an active coldness source according to an embodiment of the active coldness source, according to the present disclosure in combination with one or more embodiments.

— According to an embodiment of the present disclosure, in combination with one or more embodiments, the refrigeration device comprises at least one of the follow- ing: A refrigerator, morgue room with at least one cabinet, repository of biological material, household refrigerator, a bio-medical use refrigerator, chemical storage room with at least one cabinet, a portable refrigerator, a car-borne refrigerator and S 25 amedical refrigerator, or a combination thereof. s The utility of the present invention follows from a plurality of factors depending <Q on each particular embodiment. In an external power-loss situation of a low-tem- & perature device, phase transition bound latent heat amounting coldness can be used E maintaining acceptably a continued temperature condition inside the low-temper- © 30 ature device. The volume of the coldness storing substance can be minimized by 3 the embodied modular structure, the active coldness source module being situated N into an integrated package of controller and the storing mass modules. By using N mechanical thermostats in the controller, the dependence on the external power can be gained. The thermostats can be place so that they can operate according to — the temperature in the airflow of the suction and/or blowing side of a fan.

In a simple embodiment, the thermostat can switch the fan into operation, so that cold air can be circulated from the active coldness source to the cabinet interior of the low-temperature device. The modular structure facilitate variability of the ca- pacity of the active coldness source according to the low-temperature device’s size, ie. provides a scalability. The active coldness source modules, such that has one or more modules of storage mass, can be added in a post-manufacture phase to refrigeration devices even if there was not originally yet such, but has some room for modules, for example. The compact and modular design minimizes also the waste-volume, and provides a hygienic implementation. — The expression “a number of” refers herein to any positive integer starting from one (1), e.g. to one, two, or three. The expression “a plurality of” refers herein to any positive integer starting from two (2), e.g. to two, three, or four. Different embodiments of the present disclosure of the invention are disclosed in — the dependent claims and in suitable part in the examples.

BRIEF DESCRIPTION OF THE RELATED DRAWINGS Fig. 1 illustrates an ordinary known low-temperature device as such, As the Fig 1 illustrates an ordinary known low-temperature device as such, in the following with reference to figures Figs 2 to 11 examples of embodiments of the invention in accordance of the present disclosure are illustrated in the following in more detail with reference to the appended drawings, in which Fig 2 illustrates examples of embodiments of an active coldness source implemen- o tation according to the disclosure in combination with one or more embod- O iments, S 25 Fig. 3 illustrate a low-temperature device example using coldness source according = to the disclosure in combination with one or more embodiments, E Fig. 4 illustrates a control center of a low-temperature device example using cold- © ness source according to the disclosure in combination with one or more 3 embodiments,

O S 30 Fig 5 illustrates embodiments of refrigeration system with refrigeration devices according to the present disclosure, in combination with one or more em- bodiments.

Fig. 6 illustrates via state graph an operation of an embodiment in a cooling cycle, in combination with one or more embodiments, Fig. 7 illustrates via state graph an operation of an embodiment in an off cycle mode, in combination with one or more embodiments, Fig. 8 illustrates via state graph an operation of an embodiment when a defrosting period is about to end, in combination with one or more embodiments, Fig. 9 illustrates via state graph an operation of an embodiment when a power loss event has just begun, in combination with one or more embodiments, and Figs. 10 and 11 illustrate via the respective state graphs operation of an embodi- ment during a power loss event, in combination with one or more embodi- ments.

DETAILED DESCRIPTION OF THE EMBODIMENTS Fig 2 illustrates examples of embodiments of an active coldness source 200 imple- mentation according to the present disclosure in combination to one or more em- bodiments. In the example of Fig 2, the embodied active coldness source 200 com- prises a number of modules M1, M2, M3, M4 and Mn. According to an embodi- ment, each module comprises a module specific mass of storing substance. Thus, the M1, M2, M3, M4 and Mn represent also the corresponding masses of the mod- ules, which can be embodied equal, but are not necessarily such. The storing sub- — stance has a composition, for example, water and alcohol, that composition having a storing substance specific latent heat in phase transition, from solid to liquid or vice versa, to occur in the storing substance specific phase transition temperature. According to an embodiment example, the composition of the storing substance S has been chosen to be a mixture of water and alcohol to yield the phase transition N 25 temperature (between solid and liquid) to occur in -4 centigrades, for the illustra- 3 tive purposes for later shown examples. a With this phase transition temperature, and the composition of storing substance, E the mass in the modules has been chosen so that each module could store 400 Wh © coldness energy corresponding the phase transition of the storing substance. On 3 30 the basis of the embodiments, a skilled person knows that one can make the mod- S ules with different masses too, for different coldness energy storage capacity than S the named ca.400 Wh. On the basis of the embodiments, a skilled person knows that one can make the modules with different storing substance compositions too, for different phase transition temperatures than the named -4 centigrades.

A skilled person knows from the embodiments, that other substances than mere water, or in combination to alcohol, can be used, for adjusting the phase transition temperature, as phase transition temperature adjusting agent, for a specific refrig- eration device for a suitable operating temperature, for the coldness storing as based on phase transition and the related latent heat of the composition. According to an embodiment, the storing substance can comprise such a composition, that exhibit multiple phase transition temperatures by several composition constituents. In Fig 2, the active coldness source 200 has been embodied as a module itself as such. According to an embodiment, the active coldness source 200 can comprise a fan FI, for circulation of the air of the hosting low-temperature device, via the active coldness source 200. In some embodiments, the active coldness source 200 can use the hosting low- temperature device’s own fan, and thus the fan F1 as well as the fan F2 are drawn with the dashed line, to indicate certain optionality, although the active coldness — source 200 can have even two fans F1, F2 one for input flow and the other for output flow. Therefore, with two fans the airflow can be adjusted. That can be an advance also, if/ when the module 200 has to be mounted with long pipes accord- ing to the hosting low-temperature device structures and/or dimensions. However, as at least one of the fans F1 and F2 is intended to be battery operated, for operation — during external power loss situations, the module 200 can be advantageously em- bodied with at least one battery operated fan.

According to an embodiment, the active coldness source module 200 comprises a Battery, which is of re-chargeable type. The Battery can also comprise a super condenser/capacitor for storing energy. The Battery is embodied into the module — for making sure that at least one of the fans F1, F2 would be ventilating in an S external power loss situation. The battery can have its recharging electricity from N the hosting low-temperature device, during its normal operation. The dashed line x of the battery module is indicative optionality, for such low-temperature devices S that may have already a battery with sufficient capacity for external power loss I 30 situations, and electricity is available also for the use of the module 200 with at = least one of the fans F1, F2. 3 The active coldness source module 200 can comprise a controller 400, indicated S by the markings Control, 400. The controller Control, 400 can be implemented in S many ways, of which some examples are discussed via the example of Fig 4. Ac- cording to an embodiment, even if the controller were embodied with micropro- cessor and/or a display, the thermostat controlling the fans during operation at the release and/or storage of the coldness from/to the active coldness storage module is embodied as a mechanical thermostat, to make sure the fan operation at external power loss situation or other electric fault situations outside the battery and the fan.

Fig. 3 illustrate an ensemble of low-temperature device 300 examples using active coldness source 200 according to embodiments of the disclosure in combination to one or more embodiments.

According to the Fig 3 example, an active coldness source 200 is placed to the upper part of the refrigerator device 300. In Fig 3, the dashed line around the active coldness source module 200 has been used for better distinguish the module 200 — from the technical drawing example. According to an embodiment the module 200 has been mounted to the upper part of the refrigerator unit 300, where there is also the refrigeration apparatus 301 situated above the module 200 position. This way the thermal heat would minimize its influence to the cold parts 303 of the device

300.

— This way, it also provides an advantage that the air circulation through evaporator can be provided with relatively short air channels compared to the low-temperature device’s dimensions. In addition, the module 200 being positioned to the cabinet volume 303, to the upper part of it, provides a further advantage as the cold air being heavier than warm, the coldness from the module 200 can flow downwards in an external power loss situation. The airflow channel through the evaporator is designed so that a part of the airflow would go through the active coldness source, to provide the phase transition in the phase transition temperature.

The technical drawing in Fig 3 comprises also in the cabinet 303 cabinet parts 304, 305 and 306 as examples to embody an example about sections of the cold cabinet. However, although basket-type structures and shelf as such being illustrated as to N belong to the cabinet parts, in some embodiment variants, also different sections 5 can be used, in respect to the shelves, baskets and/or the section volume size, for <Q example.

O 2 According to an embodiment variant, sections even with own hatches each to pro- = 30 vide such sub-cabinets 304, 305, 306 to the cabinet 303 can be embodied. Accord- © ing to an embodiment, the sub-cabinets each or a number of them can have a sub- D cabinet specific module 200 of its own. O Such sub-cabinets may be useful in embodiments directed to for example to morgue applications, or large laboratory low-temperature rooms/devices, as well asin biological and/or medical repository applications.

Although the refrigerator 300 in Fig 3 has been drawn as a closure or a cupboard or a cabinet in its embodied example size, skilled person in the art realizes that the refrigerator 300 can be embodied also in a larger scale, up to a cold room.

In such embodiments the safeguard time for power loss survival without deteriorated con- tent, would be the same as for a small cabinet, but then the modules M1, M2, M3, M4, and Mn in the active coldness source can be scaled accordingly.

The number of the modules (Mn) can be increased according to the demand, but also the ca- pacity can be scaled easily by scaling the storing substance mass in each modules.

It is expected, that for example, ten times larger mass of the storing substance in one or more modules would be able to store coldness energy ten times the coldness energy of the same number of modules in the examples with 400 Wh capacity per module.

Fig. 4 illustrates a control center (Control, 400) of a low-temperature device ex- ample using coldness source according to the disclosure in combination to one or more embodiments.

According to a simple embodiment, the control center 400 is a thermostat that switch on and/or off at least one of the fans F1 and F2 as shown in Fig 2 exemplifying the active coldness source 200 as a module.

According to an alternative embodiment implementation, a controller 400 may comprise the battery, as indicated in Fig 4 with the word Battery.

According to an embodiment, the Controller 400 has been safeguarded by the battery for a safe- guard period of the active coldness source 200 to survive an external power loss of the hosting low-temperature device, and consequently provide the electricity feed to the controller 400, but also for at least one of the fans F1, F2. According to an embodiment, the controller 400 can be implemented by a micro- — processor uP.

The thermostat functionality may be available with further options S with microprocessor controller than with a mere single electromechanical thermo- & stat in simple embodiment, (possibly in simple embodiment with an operation x logic to guide fan operations). According to an embodiment, the controller 400 can S control operations of the fan FI, (also fan F2, if/when F2 present in an optional I 30 embodiment) in the module 200. c According to an embodiment, the controller 400 can also control the operation of 3 the evaporator V, which is useful in such embodiments where there is a dedicated cold charger in operation to cool at least one of the modules (Mn) of the active S coldness source 200. In addition, the refrigeration process’s storing phase duration can be adjusted according to the coldness storing needs.

According to an embodiment, the controller 400 can control timer related func- tions, to switch on and offs, for example those of the fans F1 and F2. According to an embodiment, the controller can have an interface INF for remote access.

The remote access can be embodied for an external display, and/or a functional data connection to acquire operational controlling schemes into the memory M for ex- ecution by the microprocessor uP.

According to an embodiment the controller can be connected to a key-board with buttons and a display, to provide an access to a user via a user interface to set the controller operations, such as for example the cabinet temperature.

According to an embodiment, the controller is connectable to a display of the hosing low-temperature device, which option is indicated with the dashed line rectangle around the word Display.

According to an embodiment, the controller can be with the module 200 (Fig 2), with the hosting low-temperature device 300 (Fig 3) in a laboratory, but the display can be even in a control room of a biological or medical department in an administrative building.

The controller 400 can have an access to a display, which can be low-temperature devices own, or an external display, even in a remote monitoring location.

The box P is indicative of power presence sensor, and/or a power meter, to measure power of the hosting device, so that the microprocessor can calculate from the temperature data an estimate about the available safeguard time with the present — active coldness source module 200 in the hosting low-temperature device.

According to an embodiment the Controller can have interface also to several measurement places for temperature measurements in the hosting low-temperature device and/or the module 200, i.e. the modules M1, M2, M3 in the module 200, so that it is possible to track would the estimate about the safe-guard temperature/time hold, but also simply monitoring the temperatures in said modules M1, M2, M3. o Although the expression T(Tb, Ts, M1, M2, M3) refers to the temperatures as O measured at the pressurized side (Tb) of the cabinet fan, and/or after the evapora- + tor, at under pressure side (Ts) at the suction side of the cabinet fan, and/or before = the evaporator, but as well to the temperatures of the modules M1, M2, M3. Tem- 2 30 peratures can be measure also in other places relevant to the hosting low-tempera- = ture device.

For example, the external temperature outside the cabinet can be meas- © ured to provide information about the thermal flux through the insulation of the D hosting low-temperature device’s insulation, to provide information to influence O to the refrigeration process's cycle for the active coldness producing repeating fre- quency and/or duration to hold a certain temperature in the low-temperature de- vice’s cabinet.

That information can be used also in estimating dynamically the safeguard time, also in varying conditions, provided that the controller has the microprocessor, or an interface to such, at a remote location at least. Fig 5 illustrates embodiments of refrigeration devices according to the present dis- closure, in combination to one or more embodiments. In Fig 5, there are three low- temperature devices 300 indicated, with the additional markings 300.1, 300.2 and

300.3, for exemplifying them as different kind of low-temperature devices as re- frigeration devices in a refrigeration system 500 that can use such active coldness sources 200 as embodied. The modules 200 in them are marked also with the ad- ditional markings 200.1, 200.2 and 200.3, to indicate that the modules can be dif- ferent from each other, in respect of the features such as mass of the modules (i.e. Mn), storing substance with the specific composition in them (Mn) as well as the number n of the modules (Mn), dependently on the refrigeration process details of the refrigeration devices as such. — The features may be selected to differ as based on the temperature ranges of the refrigeration devices in the system 500, as follows: active coldness source module

200.1 operable in the temperature range 10°C< T<-4°C, active coldness source module 200.2 operable in the temperature range -10°C< T<-20°C, and the active coldness source module 200.3 operable in the temperature range -40°C< T<- 190°C. For each of the active coldness source modules 200.1, 200.2 and 200.3 the storing substances and their masses are module specifically selected to provide a low-temperature device specific safeguard time against external power loss occur- rences. As the way of drawing is indicative, the cabinet volumes 303.1, 303.2 and

303.3 can be also low-temperature device specific, in respect of the interior fur- — nishing, size, dimension and/or insulation thickness and material. S According to an embodiment, such a system may comprise at least one of the re- N frigeration device such as a refrigerator, morgue cabinet, repository of biological x material, household refrigerator, a professional use lab-refrigerator, chemical stor- S age cabinet, a portable refrigerator, a car-borne refrigerator and a medical refrig- I 30 erator, or a selected combination thereof. o In Figs 6 to 11, operation of the active coldness source module 200 within a hosting 3 low-temperature device 300 has been demonstrated in the examples referring to S these Figs.

N Fig. 6 illustrates via a state graph an example of operation of an embodiment in a cooling cycle, in combination with one or more embodiments. Accordingly, the views in Figs 6 to 11 have been shown as they would be visualized/illustrated on a display of such an embodiment of the present disclosure that has a display (or an external display with functional connection in use, with suitable interface) for state graph views at the low-temperature device, for illustrating the operation of the low- temperature device using an embodied active coldness source.

Although the active coldness source operation being explained via displayed quan- tities for demonstrative purposes, the active coldness source 200 and its use in a low-temperature device (such as in example of Fig 3and/or Fig 5) can be embodied without such display in a simple variant of the embodiments.

The word “control” in Figs 6 to 11 refers to that the operation would be embodied under a controlling control module 400 and/or a thermostat to switch the fans for the embodied flow and direction through the active coldness sources.

The cabinet fan can be also in control of the controller 400. The capacities of the modules M1, M2 and M3 has been illustrated by a percentage, how much of the coldness energy corresponding the latent heat of phase transition (between liquid and solid phase) would be still available.

The temperature of each module has been also indicated on the displayed/illustrated view.

However, in a simple variant of the embodiment that does not have a display or an interface connection to such, nor temperature module specific measurement facil- ity, can be operable via a suitable thermostat that is pre-set to the switching tem- perature at the phase transition temperature of the storing substance’s composition to switch the fans on and/or off according to a pre-selected scheme for facilitating the air circulation flow through the active coldness source and the operational state corresponding direction of the flow.

In the examples of Figs 6 to 11, an active coldness source 200 as embodied in Fig o 25 2hasbeen used with three Modules M1, M2 and M3, to illustrate the embodiments O in operation. x In the examples of Figs 6 to 11, operation during 24 hours safeguard time without S external power has been demonstrated.

The cabinet temperature of the low-tem- I perature device has been exemplified to 8 centigrades, assuming the ambient tem- - 30 perature of the low-temperature device would not exceed 40 centigrades in the 3 example.

N In Fig 6, during the cooling cycle, there is -10 centigrade airflow flowing through N the active coldness source, as blown through the evaporator to decrease the tem- perature of the through-going air.

The arrows in the graph above the modules M1, M2andM3 indicate air circulation to cool the active coldness source comprising these three modules in the example, down to -4 centigrades temperature.

In the example of embodiment, with -6 centigrade temperature difference and 25 m*/h airflow the coldness charging power is estimated to about 54 W.

As illustrated in Fig 7, during the off cycle period of the low-temperature device, both of the two embodied fans of the example are rotating and thus ventilating, so that through the evaporator/charger there is an air flow of 5 m*/h with 6 centigrade temperature difference.

The coldness charge is discharging by an 11 W power.

The airflow direction in the active coldness source has been reversed as indicated by the arrows at the Airflow -marking in the active coldness source.

Accordingly, to provide coldness energy of 1200 Wh to the active coldness source 200, the time for full coldness energy of 1200 Wh would take about 28 h in the example, assuming that there is an in-duty period of 0,5 of the operation time.

Therefore, the off cycle period would be also 0.5, or in other words, 50% of the refrigeration cold-cycle to maintain actively the temperature by the refrigeration — process to the pre-set value of the embodied example, and 50% of off cycle.

In the examples of Figs 6 to 11 three active coldness source modules M1, M2, M3 are embodied, without any intention to limit the number of the active coldness source modules only to the exemplified values.

For about 1200 Wh capacity of coldness energy, three modules each with a capacity about 400 Wh/ has been em- bodied, with an applied composition of water and alcohol for the storing substance and its storage mass.

According to an embodiment variant the number of the mod- ules could be even higher, depending on the size and capacity need of the low- temperature device into which the active coldness source is intended to be mounted for a certain safe-guard time period.

Assuming that the embodied three modules in the module pack/chassis of the ac- N tive coldness source would store 1200 Wh of coldness energy for an intermediate 5 refrigerator, having in the modules a module specific storage mass of storing sub- <Q stance comprising a dedicated composition of a solution to provide the storage a mass, the total storage mass being formed from a selectable number (n, Fig 2) of E 30 the modules (Mn, Fig 2). Although the equal drawn size of the modules in the © example, a skilled person knows from the embodiments that the modules does not 3 need to be equal in size, dimensions, mass or capacity to store coldness energy, S but the dimensions can vary according to the size of the low-temperature device, S its cabinet volume, as well as the ambient temperature in the use.

However, an embodied active coldness source comprising a modular system with certain stand- ard modules specifications makes the extensions/reductions at the mount to the low-temperature devices such as cold-rooms and/or refrigerators very flexible.

Thus, the active coldness sources 200 according to the embodiments can be used in such low-temperature devices as refrigeration devices that embody cold rooms of restaurants, medical/biological utilities and/or morgues, which may be extended or reduced in the respect of their volume, the active coldness source being updated accordingly, if such modification found necessary for a new utilization concept.

Example 1 With reference to the Fig 6, the active coldness source 200 in Fig 6 is in a refrig- eration device.

Under control, the active coldness source 200 is on duty, and the mode, as indicated by the bold face text Mode, is loading, which means that the active coldness source 200 is storing coldness energy to the modules M1, M2 and M3. The evaporator V, being considered as a coldness charger as such, is operable, by an external power source in the example.

In gas operated refrigeration devices, the gas powering for the operation is consid- ered as external power.

The cooling operations to charge coldness of the evapora- tor is based on a circulating refrigerant being allowed to expand in/to gaseous phase and consequently reduce the temperature.

In Fig 6, there is indicated a suction air with a temperature and/or flow sensor.

The sucked air is in temperature of 5 centigrades, and when mixed with the airflow from the active coldness module, provide an airflow in temperature of 3 centi- grades at the over pressure side of the fan, the air to be blown through the evapo- rator.

As the duty on, the evaporator V is cooling and the temperature drops to -10 cen- tigrades when air flows through the evaporator V.

The -10 centigrades air is flown S 25 — to the cabinet of the low-temperature device, but also via a side flow, flows into & the active coldness source 200, in which the -10 centigrades’ air is cooling the x modules M1, M2 and M3, to turn/keep the storing substance in them in a frozen S solid state, in the example in -4 centigrade temperature.

E In the Example 1, the storing capacity of coldness energy is indicated in Whs.

In © 30 the situation the stored coldness energy being fully (100%, in all modules) availa- 3 ble.

As the refrigeration process is going on, there is no need to use the stored coldness energy, and therefore the amount of used is indicated as zero, and avail- N able as left 1295 Wh.

In the example, the low-temperature device has a cabinet fan on, which corre- sponds the suction air, to suck air to be delivered through the evaporator V, and via the side flow through the active coldness source 200. The fan (i.e. in Fig, F1 or F2) to supply cold air to the active coldness source 200 is off. This fan has been indicated as a fan of the active cold source as the cold source fan, which is off. The flow rate is indicated to be -25 m3/h at the cabinet fan at the suction site, the sign being indicative to the direction of the airflow in the cabinet. Example 2 With reference to the Fig 7, the same low-temperature device with the same active coldness source 200 as in Example 1 has been reached the pre-set cabinet temper- ature, and the refrigeration cycle has been adjusted slower or stopped to avoid un- — necessary power consumption, for example. Consequently the low-temperature device has as its mode as indicated off cycle period. As the refrigeration process being on off cycle period, the suction air temperature has been measured by a temperature sensor, to 6 centigrades for the cabinet fan location. As the powers are still available, the cabinet fan is in on state, as well as — the active cold source fan (delivering airflow through the active coldness source 200). At the site after evaporator V, the airflow temperature is about 5 centigrades. Because the active coldness source 200 has been activated to cool the cabinet air, the sucked air from the cabinet has changed the flow direction according (the ar- rows) to the control module, and the air flow has started to flow to a reverse direc- tion as in Example 1 in the active coldness source 200. Because of the coldness being caught from the active coldness source to the air- flow, the temperature at the output site of the active coldness source 200 is about 0 centigrades, which yield with the flow through the evaporator a cabinet temper- S 25 ature of 4 centigrades when flows are mixed and are conducted to the cabinet. s At the left side the indicated Stored energy of 1295 Wh has been reduced by the I used 5 Wh, so that there is still left 1290 Wh of coldness energy. The air flow a through the active coldness source 200 (i.e. cold source in Figs 6 to 11) is indicated E to be 5 m*/h, the missing sign indicating the direction of the air flow in the active © 30 coldness source 200, illustrated by the drawn arrows therein. o

D S Example 3 N With reference to the Fig 8, the same low-temperature device with the same active coldness source 200 as in Fxamples 1 and 2 has been continued to a mode in which the low-temperature device is defrosting (i.e. frost or ice removal from the cabinet interior), and the defrosting period is about to end.

The refrigeration cycle has been stopped to avoid unnecessary power consumption.

Consequently the low-temper- ature device has as its mode as indicate as defrosting ending.

According to an em- bodiment, the fan of the active coldness source is operating, to increase the pres- sure in the active coldness source, so that the thermostat-controlled operation makes the pressure increased slightly to the same level as in the airflow channel, so aiming to the maintaining of the temperature in the active coldness source.

Ac- cording to an embodiment, a fan can be embodied with a capacity for a higher pressure than in the airflow channel (the channel part leading to the evaporator), so to mitigate temperature variations in the low-temperature device during defrost- ing states.

As the refrigeration process being on the off cycle period, being extended to de- frosting, the suction air temperature has been sensed by the sensor to 7 centigrades for the cabinet fan location.

As the powers are still available, the cabinet fan is in — on state, as well as the fan of the active coldness source 200 (delivering air flow through the active coldness source 200). At the site before and after evaporator, the respective airflow temperatures are about 7 and 5 centigrades.

Because the active coldness source has been activated to cool the cabinet air in the situation of the example, the sucked air from the cabinet has been changed the flow — direction in control of the control module, and the air flow has started to flow to a reverse direction compared to that in Example 1 in the active coldness source 200, at the indicated flow rate 5 m”/h.

Because of the coldness being caught from the active coldness source to the flow through the active coldness source 200, the temperature at the output site of the — active coldness source 200 is still about 0 centigrades, which yield with the flow S through the evaporator a cabinet temperature of 4 centigrades when flows are N mixed and are conducted to the cabinet.

S At the left side the indicated Stored energy of 1295 Wh has been reduced by the & used 10 Wh, so that there is still left 1285 Wh of coldness energy.

The air flow E 30 through the active coldness source 200 (i.e. cold source in Figs 6 to 11) is indicated © to be 5 m3/h, the missing sign indicating the direction of the air flow in the active 3 coldness source in accordance of the arrows in Fig.

The coldness energy being S used is still not very much from the capacity, below one percent, and is not shown S in the capacity indications of the modules M1, M2 and M3 of 100%.

Example 4 With reference to the Fig 9, the same low-temperature device with the same active coldness source 200 as in Examples 1, has been continued to an in-duty mode, and after getting full capacity of the active coldness source modules, suddenly experi- ences a power loss period to begin, with the indicated power loss mode (in hours, h). The refrigeration process has been stopped, as there is no external energy source to maintain said process because of the power loss situation.

Consequently, the low-temperature device mode has been indicated as power loss.

As the refrigeration process being not available during a power loss, the cabinet — fan suction has been also stopped and the sensed temperature by the sensor is about 7 centigrades at the stopped cabinet fan.

As the powers are not available, the cab- inet fan is in off state.

However, the active cold source’s 200 fan (i.e. in Fig FI and/or F2), delivering air flow through the active coldness source 200, that has been activated by the control module (i.e. 400 in Fig 2) so that the flow through — the active coldness source is 30 m/h.

At the sites before and after evaporator V, the respective temperatures are both about 7 centigrades.

The airflow through the evaporator V has been stopped at the external power loss.

Because the active coldness source 200 has been activated to cool the cabinet air in the power loss situation of the Example 4, the sucked air from the cabinet has been changed the flow direction in command of the control module (i.e. 400 in Fig 2, Fig 4), and the air flow has started to flow to a reverse direction as in Example 1, in the active coldness source 200, through it, at the indicated flow rate controlled to 30 m*/h. o 25 Because of the stored coldness being started to cool the cabinet, as caught from the O active coldness source 200 to the flow through it, the temperature at the output site < of the active coldness source is still about 2 centigrades at the beginning of the = power loss situation in the example.

There is no cabinet fan originating flow, as 9 there is no power for the operation.

Therefore, the flow through the active coldness E 30 — source sets the cabinet temperature to 2 centigrades.

S At the left side the indicated Stored energy of 1295 Wh has not been reduced yet, S as 0 Wh being indicated as used, so that there is still left 1295 Wh of coldness I energy.

The airflow through the active coldness source 200 (i.e. cold source in Figs 6 to 11) is indicated to be 30 m3/h, the missing sign indicating the direction of the airflow in the active coldness source 200. The coldness energy being used has not started yet to influence to the available capacity of the coldness energy and the indications of the modules M1, M2 and M3 indicate 100% capacity left.

Example 5 With reference to the Fig 10, the same low-temperature device with the same active coldness source as in Examples 1 and 4 has been continued its mode in the power loss mode during 12 h. The refrigeration process has not been started, as there is no external energy available because of the power loss situation. Consequently, the low-temperature device mode has being indicated as power loss.

As the powers are not available, the cabinet fan is in off state. As the refrigeration — process being not available during a power loss, there is no cabinet fan’s airflow, as the cabinet fan has been also stopped. The temperature measured by the sensor is about 8 centigrades at the stopped cabinet fan, after 12 h power loss. However, the active cold sources 200 fan FI, (optionally or in addition F2), delivering air- flow through the active coldness source 200 has been activated by the control mod- ule so that the flow through the active coldness source is 30 m*/h, the fan being energized by a battery that is rechargeable type. The battery capacity being de- signed for the pre-estimated safeguard period for the fan operation.

At the sites before and after evaporator the respective the temperatures are both risen to 10 centigrades, as there is no airflow through the evaporator.

Because the active coldness source 200 has been delivering at the input site of it air flow in 8 centigrades temperature, the module M3 has been emptied from the coldness energy, as all the latent heat has made the phase transition in the module to occur, and it is not able to give remarkably further coldness energy based on the phase transition bound latent heat. The module M3 has been warmed to 5 centi- S 25 grades.

5 In module M2 there is still 10 % of latent heat proportional coldness energy avail- <Q able, and the storage mass has its temperature in -4 centigrades. In module M1 & there 1s still 50% of latent heat proportional coldness energy available, and the E storage mass has its temperature in -4 centigrades.

© 30 — The indicated flow rate through the active coldness source is controlled to 30 m?/h.

<r S Because of the coldness being used during 12 h to cool the cabinet, as caught from I the active coldness source to the flow through the active coldness source, the tem- perature at the output site of the active coldness source is still about 3 centigrades, as also in the cabinet.

At the left side the indicated Stored energy of 1295 Wh was reduced by 600 Wh, as being indicated as used, so that there is still left 695 Wh of coldness energy.

The airflow through the active coldness source (i.e. cold source in Figs 6 to 11) is in- dicated to be 30 m3/h, the missing sign indicating the direction of the airflow in the active coldness source, as illustrated by the arrows.

The coldness energy being used has influenced to the available capacity of the coldness energy and the indi- cations of the modules M1, M2 and M3 has still 60% capacity of a single module available, if the M1 were with equal capacity as the M2 and M3. Consequently, with similar modules as the M2 and M3, it would have been possi- — ble to embody such an active coldness source for low-temperature device that would have exhibited 12 h safeguard time in a power loss situation, in a safeguard temperature of the cabinet below 4 centigrades.

Example 6 With reference to the Fig 11, the same low-temperature device with the same active coldness source as in Example 5 has been facing power loss situation being con- tinued in the mode during 24 h.

Consequently, the low-temperature device mode has being indicated as power loss 24 h.

The temperature measured by the sensor is about 9 centigrades at the stopped cab- inet fan, after the 24 h power loss.

However, the active cold source fan as battery — operated, is delivering airflow through the active coldness source at flow rate of m*/h.

The battery capacity being designed for the pre-estimated safeguard pe- riod.

According to an embodiment variant, a super capacitor can be used as option to a battery.

At the sites before and after evaporator V the respective temperatures are both risen o 25 to 10 centigrades, as there is no airflow through the evaporator V, because of the O power loss. 3 Because the active coldness source 200 has been delivering at the input site of it S air flow in 9 centigrades temperature, the modules M2 and M3 have been emptied I from the coldness energy, as all the latent heat bound coldness energy has made - 30 the phase transition in the modules to occur completely, and they are not able to S give remarkably further coldness energy.

The modules M2 and M3 have been S warmed to 5 centigrades.

S In module M1 there is still 10 % of latent heat proportional coldness energy avail- able, and the storage mass has its temperature in -4 centigrades.

The indicated flow rate through the active coldness source is controlled to 30 m*/h.

Because of the stored coldness being used during 24 h to cool the cabinet, as caught from the active coldness source 200 to the flow through the active coldness source, the temperature at the output site of the active coldness source 200 is still about 4 centigrades, also in the cabinet.

At the left side the indicated Stored energy of 1295 Wh was reduced by 1200 Wh, as being indicated as used, so that there is still left 95 Wh of coldness energy. The airflow through the active coldness source (i.e. cold source in Figs 6 to 11) is in- dicated to be 30 m3/h, the missing sign indicating the direction of the airflow in the active coldness source, as illustrated by the arrows. The coldness energy being used has influenced to the available capacity of the coldness energy and the indi- cations of the modules M1, M2 and M3 has yet 10% capacity of a single module available.

Consequently, it was demonstrated possible to embody such an active coldness source for low-temperature device that would have exhibited 24 h safeguard time — period in a power loss situation, in a safeguard temperature of the cabinet equal to or below 4 centigrades.

Consequently, a skilled person may on the basis of this disclosure and general knowledge apply the provided teachings in order to implement the scope of the present invention as defined by the appended claims in each particular use case — with necessary modifications, deletions, and additions.

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Claims (15)

Claims

1. An active coldness source (200) of a low-temperature device, characterized in that, the active coldness source (200) comprises one or more modules (M1, M2, M3, M4, Mn) each comprising a storage mass of coldness storing substance to store cold- ness energy into the storage mass of the coldness storing substance in said one or more modules (M1, M2, M3, M4, Mn) during storing mode of the active coldness source, the active coldness source during which being cooled into a phase transition temper- ature, and/or a further lower temperature, of the storing substance in said one or more modules (M1, M2, M3, M4, Mn).

2. The active coldness source (200) of claim 1, wherein the active coldness source (200) comprises masses of the storing substance in said one or more modules (M1, M2, M3, M4, Mn) being selected to correspond by the latent heat of phase transition of said storing substance, to provide the coldness being stored into the mass of said storing substance in a pre-determined safeguard temperature, the safe guard tempera- ture being provided by the corresponding coldness energy to the latent heat of the storing substance’s mass, during the temperature of the phase transition as a safeguard period of time.

3. The active coldness source of claims 1 or 2, wherein the storage mass of the storing substance in the active coldness source (200) is proportional to a number of the one or more modules (M1), (M2), (M3), (M4), (Mn) of said storing substance.

4. The active coldness source (200) of claims 1, 2 or 3, wherein the composition of the storing substance comprises water in the mass of the storing substance to deter- mine the phase transition temperature of the storing substance by the water abundance — in said mass of the one or more modules (M1, M2, M3, M4, Mn). N

5. The active coldness source (200) according anyone of the claims 1 to 4, wherein 5 the composition of the storing substance comprises, in addition to water, a phase tran- ? sition temperature lowering agent, to provide a pre-set phase transition temperature to a one or more modules (M1, M2, M3, M4, Mn). E 30

6. The active coldness source (200) according anyone of the claims 1 to 5, wherein © the safeguard period of time is pre-set to correspond by the storing substance’s mass D bound latent heat, during the duration of the phase transition. S

7. The active coldness source (200) according anyone of the claims 1 to 6, wherein the active coldness source (200) comprises a fan arranged to circulate air of a hosting low-temperature device, the air being conducted at least partly into thermal commu- nication, via surfaces of said one or more modules, with said storing substance.

8. The active coldness source (200) according anyone of the claims 1 to 7, wherein the active coldness source (200) comprises a dedicated coldness charger in the active coldness source (200) to charge the coldness to the storing substance via a thermal communication, as based on the refrigerant of the hosting low-temperature device.

9 The active coldness source (200) according to anyone of the claims 1 to 8, wherein the storing substance comprises a liquid composition to form a latent heat based coldness storage in the phase transition at the freezing point of the storing sub- stance, to store and/or release said latent energy at the freezing point temperature ac- cording to the mode of said active coldness source (200).

10. The active coldness source (200) according to anyone of the claims 1 to 9, wherein the active coldness source comprises a control logic (Control) to detect as an initiative a power loss and/or a temperature threshold in the hosting low-temperature device’s cabinet’s storing volume interior being met for triggering a counter measure to at least one of said initiatives.

11. The active coldness source (200) according to anyone of the claims 1 to 10 wherein a counter measures comprise to activate the active coldness source (200) into state to release coldness, by the phase transition of the storing substance proportion- ally to the latent heat of said storing substance, from the storing substance.

12. The active coldness source of anyone of the previous claims, wherein the re- lease is implemented into an air flow maintained by a battery operable fan, the flow being conducted to flow in thermal communication with the storing substance in the active coldness source (200) via surfaces of said one or more modules.

13. The active coldness source of anyone of the previous claims, wherein the active coldness source comprises at least one of S 25 -afirst thermostat configured to control the operation of the coldness charger active N when storing and/or releasing coldness into/from the storing substance, and <+ <Q - a second thermostat in the control logic, configured to control the operation of the O . . . . O coldness charger into storing and/or release mode when storing and/or releasing cold- E ness from the storing substance as a counter measure to at least one initiative © 30

14. A refrigeration device (300) comprising an active coldness source (200) ac- = cording to anyone of the previous claims. N

15. A refrigeration device (300, 300.1, 300.2, 300.3) of claim 14, comprising at N least one of the following: A refrigerator, morgue cabinet, repository of biological material, household refrigerator, a professional use refrigerator, chemical storage cab- inet, a portable refrigerator, a car-borne refrigerator and a medical refrigerator.