EP2199713A2 - Container and device for indirect cooling of goods and method for producing the container - Google Patents

Abstract

The container has a container body with two container layers that are in heat conductive contact with different thermal conductivities. The thermal conductivities differ by a factor greater than 10, particularly greater than 20, particularly greater than 100. A layer with lower thermal conductivity is formed from a material which comprises stainless steel, steel, ceramics, glass, nanomaterial or plastic material. Another layer with higher heat conductivity, is formed from a material which comprises aluminum, gold, carbon, copper, magnesium, brass, silver or silicon or alloys. Independent claims are also included for: (1) a device for handling, particularly centrifugation, stirring or cooling of goods, particularly a laboratory centrifuge; and (2) a method for producing a container.

Description

The present invention relates to a container according to the preamble of claim 1, a device according to the preamble of claim 5 and a method of manufacturing the container according to the preamble of claim 7.

In particular, the present invention relates to laboratory centrifuges, i. Centrifuges used, for example, in chemical, biological, biochemical or biotechnological laboratories. On the other hand, the present invention can be advantageously used in large-scale centrifuges and mechanical stirring devices and all devices in which a good is to be cooled at least indirectly. Thus, the invention is also in pure cooling devices, such as refrigerators and freezers and especially laboratory cooling and laboratory freezers, where a very deep cooling to be achieved, can be used. In such pure cooling devices, the container forms the enclosure of the interior of the device in which the good is introduced.

In particular, the invention does not relate to cookware, frying pans or the like containers which serve to heat a good that can be arranged in the container.

Background of the invention

During centrifugation, heat is generated during the rotation of the centrifuge rotor in the centrifuge vessel due to air friction and electrical power loss. Since the centrifuge vessel is closed with a lid to prevent spillage of centrifuging, this heat input can not be easily dissipated and leads to an increase in the temperature of Zentrifugiergutes.

However, this temperature increase is usually undesirable. Therefore, precautions have been taken in the past to avoid an increase in centrifuging temperature. This can be done either by direct cooling or by indirect cooling using the heat exchanger principle. In the indirect cooling (indirect cooling) so there is no direct contact between the cooling medium and to be cooled Good or wrapping the goods to be cooled.

In direct cooling, the ambient air is passed directly through the centrifuge bowl at the centrifuge rotor, with the rotor acting as a kind of radial fan. For this purpose, the centrifuge lid and / or centrifuge bowl has an inlet opening near the axis and an outlet opening arranged at a distance from the axis of rotation. Although such direct cooling has proven itself, the centrifuge tank must have an outlet opening for it, which, however, also permits a material outlet. Such boilers are thus not suitable for stirring devices or the like, in which materials are to be mixed directly and must therefore be formed closed all around. A disadvantage of direct cooling results from the use of the ambient air as a coolant: the good can be cooled only to the maximum temperature of the ambient air.

In indirect cooling, the rotor is enclosed in the centrifuge vessel under the centrifuge lid and no cooling channel or the like is provided. The air circulates therefore only within the centrifuge bowl. Cooling is now achieved by a second medium, which is passed on the outside of the boiler. This can either be ambient air, which is conducted past the outside of the boiler, as is realized, for example, in the case of the centrifuge 5424 from Eppendorf AG. Alternatively, a special coolant is routed past the boiler via conduits spiraling against the boiler, ie the side walls and the bottom plate of the boiler, to remove heat. In the latter variant of the indirect cooling and cooling of the material to a temperature below the temperature of the ambient air is possible. An advantage of indirect cooling is the better controllability of the temperature to be set compared to direct cooling.

However, the cooling effect achieved with the indirect cooling is not yet as efficient as in direct cooling, which is why the energy consumption is correspondingly high with the same cooling capacity. This is a consequence of the areal limited contact of the cooling medium, which is led past the outside of the boiler.

Efforts are already known from the prior art to improve the indirect cooling. That's how it describes US 5,477,704 A a centrifuge vessel, on the outer side walls and the bottom plate of which cooling coils of copper are glued by means of an aluminum-filled epoxy resin. The aluminum-filled epoxy resin has a high thermal conductivity and serves to assist heat dissipation from the centrifuge bowl. The in the US 5,477,704 A disclosed cooling coils, which are glued to the boiler, are characterized by their special design: the voltage applied to the boiler side wall and the bottom plate side of the cooling coil is flattened, so as to increase the contact area between the cooling coil and boiler. However, an epoxy resin is difficult to apply to copper pipes and it takes a certain curing time before such a boiler can be used or further processed. In addition, the boiler and the composite epoxy resin / copper have different thermal expansion coefficients. The result of this is that, in the event of a change in temperature, clicks can occur which leave the user with an uncertainty with regard to the operational safety of the centrifuge.

The object of the present invention is to provide a container that allows efficient indirect cooling and is simple and inexpensive to produce. In addition, a cooperating with the container device and a method for producing the container to be provided. The container should not only be used in centrifuges, but also stirring devices, cooling devices and the like can be found.

Container in the context of the present invention are all devices in which a good to be cooled can be arranged directly or indirectly via a separate enclosure and which can be cooled by means of indirect cooling via a standing in heat conductive contact cooling device. The container according to the invention may be designed differently with respect to the outer shape. He can round or be kettle-shaped. In such a case, the container has a round bottom plate from which pulls up a side wall at the outer edge. The top of the container is closed by an openable lid. In an alternative embodiment, the container is angular, ie designed rectangular or square. He then has a rectangular or square base plate, extending from the outer edge of each four sidewalls. The top of the container is closed with a top plate. Depending on the use of the container either at least one of the side walls is designed as an openable door or the top of the container, ie the upper plate is formed as an openable lid. Whenever "sidewall" is mentioned, this term also includes the plural, ie "sidewalls".

Brief description of the invention

Surprisingly, it has been found that this object is achieved by an at least two-layer container according to claim 1. Equally surprising are the results that are achieved with a device, in particular centrifuge according to claim 5. These results are surprising because so far there were no indications that an at least two-layer centrifuge vessel can provide such a tremendous improvement in indirect cooling in a centrifuge.

1. (1) einen Behälter zur mittelbaren Kühlung von Gut in einer Vorrichtung, wie Zentrifugen, Rührvorrichtungen, Kühlvorrichtungen, wie Kühlschränken, und dergleichen, wobei der Behälter mit einer Kühleinrichtung der Vorrichtung in Wärme leitenden Kontakt bringbar ist und einen Behälterkörper aufweist, dadurch gekennzeichnet, dass der Behälterkörper zumindest zwei in Wärme leitendem Kontakt stehende Behälterschichten (10, 11) mit unterschiedlicher Wärmeleitfähigkeit aufweist, wobei die Schicht mit höherer Wärmeleitfähigkeit (11) an der durch die Kühleinrichtung zu kühlenden Behälteraußenseite angeordnet ist;
2. (2) eine Vorrichtung zur Behandlung, insbesondere Zentrifugieren, Rühren, Kühlen oder dergleichen., eines Gutes, insbesondere eine Laborzentrifuge, ein Kühlschrank, ein Gefrierschrank, insbesondere ein Laborkühlschrank- und/oder Laborgefrierschrank oder dergleichen., mit einem Behälter und einer nur bereichsweise mit einer gekühlten Außenfläche des Behälters in Wärme leitendem Kontakt stehenden Kühleinrichtung zur mittelbaren Kühlung des im Inneren des Behälters angeordnetes Gutes, dadurch gekennzeichnet, dass der Behälter als Behälter gemäß (1) ausgebildet ist; und
3. (3) ein Verfahren zur Herstellung des Behälters gemäß (1), dadurch gekennzeichnet, dass die Schicht mit höherer Wärmeleitfähigkeit (11) auf der Schicht mit geringerer Wärmeleitfähigkeit (10) angeordnet wird oder umgekehrt.

The invention thus relates

1. (1) a container for indirect cooling of goods in a device, such as centrifuges, stirring devices, cooling devices, such as refrigerators, and the like, wherein the container can be brought into heat-conductive contact with a cooling device of the device and has a container body, characterized in that the container body has at least two heat-conductive contact container layers (10, 11) with different thermal conductivity, wherein the higher thermal conductivity layer (11) is disposed on the container side to be cooled by the cooling device;
2. (2) a device for treatment, in particular centrifuging, stirring, cooling or the like., Of a good, in particular a laboratory centrifuge, a refrigerator, a freezer, in particular a laboratory refrigerator and / or laboratory freezer or the like., With a container and a region only with a cooled outer surface of the container in heat conductive contact cooling device for the indirect cooling of the goods arranged inside the container, characterized in that the container is designed as a container according to (1); and
3. (3) A method of manufacturing the container according to (1), characterized in that the higher thermal conductivity layer (11) is disposed on the lower thermal conductivity layer (10) or vice versa.

"Heat conductive contact" in the context of the present invention means that the contact must be such that the heat transfer can be carried out by heat conduction. So there must be a material contact, but this does not mean that this contact must exist directly - so between the two layers can also be arranged one or more intermediate layers. In the context of the present invention, "heat-transferring contact" means, for example, that the contact must be such that heat transfer can take place at least by one of the three principal heat transfer mechanisms, heat conduction, radiation or convection. It does not necessarily have to be a material contact. "Direct contact" between two objects in the context of the present invention means that two objects at least partially abut each other directly and thus touch each other. When in the context of the present invention is generally referred to as "contact" or "contact point", i. without the preceding words "heat conducting" or "heat transferring", this always means a direct contact.

Advantageous developments are specified in the dependent claims.

Brief description of the figures

Fig. 1

eine schematische, ausschnittsweise Darstellung eines herkömmlichen Zentrifugenkessel in Kontakt mit einer Kühlleitung und

Fig. 2

eine schematische, ausschnittsweise Darstellung eines erfindungsgemäßen Zentrifugenkessel in Kontakt mit einer Kühlleitung.

The invention is illustrated by the following figures, which are additionally explained in detail in the detailed description of the invention. Show

Fig. 1

a schematic, partial view of a conventional centrifuge vessel in contact with a cooling line and

Fig. 2

a schematic, partial view of a centrifuge vessel according to the invention in contact with a cooling line.

The container according to the invention comprises a container body which has at least two heat-conducting contact container layers with different thermal conductivity. The two container layers create a large contact area that improves heat transfer during cooling. Due to the fact that the layer with higher thermal conductivity is arranged on the outside of the container to be cooled, the heat flow is increased in the direction of the cooling device, which only conducts heat in some areas in contact with the cooling surface of the container. This results in an overall increased cooling efficiency.

In order to enable particularly efficient cooling, the thermal conductivities should differ by a factor greater than 10, preferably greater than 20, in particular greater than 100.

In a particularly preferred embodiment, the layer with lower thermal conductivity is formed from a material comprising stainless steel, steel, ceramic, glass and / or plastic and the layer with higher thermal conductivity is made of a material aluminum, gold, carbon, including its modifications graphite, diamond, diamond-like carbon and carbon nanotubes, copper, magnesium, brass, silver and / or silicon or their alloys formed. Then a particularly efficient heat transfer can be ensured and the boiler is also easy to produce. In particular, an embodiment of the layer with higher thermal conductivity than film is advantageous, for example, as a pyrolytic graphite foil (PGS), since this manufacturing technology is simply applied to the layer with lower thermal conductivity. As a layer with lower thermal conductivity, alternatively, so-called nanolayers can be used, that is to say a layer which was produced using nanotechnology. In the following, such a layer is understood to consist of a "nanomaterial".

The production costs can be reduced with good efficiency in that the layer with higher thermal conductivity has a small thickness of less than 1 mm, preferably less than 0.5 mm and in particular less than 0.2 mm. It should be noted that depending on the layer material, the heat flow at too thick layers decreases and the heat transfer may be disturbed in the case of layers that are too thin, so that there is an optimum with respect to the minimum thickness for each layer material, which the expert will find out routinely by means of tests and calculations.

Independent protection is claimed for a device for treatment, in particular centrifuging, stirring, cooling or the like of a good, in particular a laboratory centrifuge, a refrigerator, a freezer, a laboratory refrigerator, a laboratory freezer, or the like, with a container and a region only with a cooled outer surface of the container in heat-conducting contact cooling means for indirect cooling of the arranged inside the container good, wherein the container is designed as the container according to the invention.

Advantageously, the container is surrounded by a tubular conduit, which is preferably wound helically around the container. The term "tubular" includes round tubes as well as tubes with at least one flattened side, in particular also rectangular tubes.

"Only in some areas" in the context of the present invention means that the contact area between the cooling device and the cooled outer surface of the container is smaller than the cooled outer surface of the container. The cooling device can also be formed by a plurality of separately operating devices, but their total contact area should be smaller than the cooled container outer surface.

Due to the efficiency of the indirect cooling enabled, it is possible to dispense with the provision of cooling lines at the bottom of the container. However, the temperature rises exponentially in a centrifuge vessel, for example, as a function of the rotational speed, so that additional cooling lines can be provided on the bottom of the vessel for very high rotational speeds and / or desired very deep cooling.

Of course, the indirect heat transfer according to the invention can also be coupled with a direct heat transfer, for example, the known rotor air assisted centrifugal cooling.

Furthermore, independent protection for the method for producing the container according to the invention is claimed, in which the layer with higher thermal conductivity is disposed on the layer with lower thermal conductivity or vice versa. For example, this can be done by the one layer, preferably the one with the higher thermal conductivity aufplatiert on the other layer and then the container is formed or two separate layers are stacked, for example, as foils or sheets and the container, for example, by simultaneous forming, For example, deep drawing, the layers shaped.

However, it is preferable that the higher thermal conductivity layer is deposited on the lower thermal conductivity layer after the lower thermal conductivity layer has substantially the shape of the container, or vice versa, the lower thermal conductivity layer is applied to the higher thermal conductivity layer after the lower thermal conductivity layer Layer with higher thermal conductivity has essentially received the shape of the container. Then, the manufacturing process can be made more cost-effective, for example, the layer with higher thermal conductivity is galvanotechnically applied to the layer with low thermal conductivity or vice versa.

In summary, it can be stated that the inventors have recognized that in indirect cooling, the effectiveness depends substantially on the heat transfer between the elements of the heat exchanger, as will be explained below. In this case, only the heat conduction is taken into account for the description of the processes during the heat transfer and the heat radiation and convection are disregarded.

wobei Q̇ der Wärmestrom durch den Festkörper, λ die Wärmeleitfähigkeit, die eine Materialkonstante ist, A die Größe der Querschnittsfläche des Festkörpers, s die Dicke des Festkörpers und ΔT die Temperaturdifferenz zwischen der Eingangs- und Ausgangsseite des Wärmestroms sind.The heat flow within a solid is defined as: $$\dot{Q}=\lambda •\frac{A}{s}•\mathrm{\Delta }T.$$

where Q̇ is the heat flow through the solid, λ the thermal conductivity, which is a material constant , A is the size of the solid's cross-sectional area, s is the thickness of the solid, and Δ T is the temperature difference between the input and output sides of the heat flow.

The principle of the invention with its advantages will be explained in more detail below with reference to the drawing using the example of centrifuge boilers.

Based on Fig. 1 This principle is explained purely schematically for a prior art known and partially illustrated centrifuge vessel with a boiler wall 1, which is in contact with a cooling line 2. The illustrated by the arrows heat flow from the boiler inside 3 flows at a temperature T ₁ through the boiler wall 1, which has a wall thickness s ₁ , via the contact surface A between the boiler wall 1 and the cooling pipe 2 with a temperature T _A through the cooling medium leading material Cooling line 2, which has a wall thickness s ₂ , wherein the cooling medium has the temperature T ₂ .

und für den Wärmestrom durch das Kühlmedium führende Material der Kühlleitung 2: $${\dot{Q}}_2={\lambda }_2•\left(T_A-T_2\right)$$

For simplicity, the assumptions are further made that the wall thicknesses s ₁ and s _{2 are the} same, that is s = 1 mm, the cross-section of the contact surface A = 1 mm ² and the heat flow outside the contact surface A is zero, there so a Air gap is present. Thus, the heat flow through the boiler wall 1 can be made only by the contact surface A and for the heat flow through the boiler wall 1 then results: $${\dot{Q}}_1={\mathrm{<figure-callout\; id="1"\; label="\lambda "\; filenames="imgf0001.png,imgf0002.png"\; state="\{\{state\}\}">\lambda </figure-callout>}}_1•\left(T_1-T_A\right)$$

and for the heat flow through the cooling medium leading material of the cooling line 2: $${\dot{Q}}_2={\mathrm{<figure-callout\; id="2"\; label="\lambda "\; filenames="imgf0001.png"\; state="\{\{state\}\}">\lambda </figure-callout>}}_2•\left(T_A-{\mathrm{<figure-callout\; id="2"\; label="T"\; filenames="imgf0001.png"\; state="\{\{state\}\}">T</figure-callout>}}_2\right)$$

After the continuity principle is $${\dot{Q}}_1={\dot{Q}}_2\mathrm{,}$$

After inserting results: $${\mathrm{<figure-callout\; id="1"\; label="\lambda "\; filenames="imgf0001.png,imgf0002.png"\; state="\{\{state\}\}">\lambda </figure-callout>}}_1•\left(T_1-T_A\right)={\mathrm{<figure-callout\; id="2"\; label="\lambda "\; filenames="imgf0001.png"\; state="\{\{state\}\}">\lambda </figure-callout>}}_2•\left(T_A-{\mathrm{<figure-callout\; id="2"\; label="T"\; filenames="imgf0001.png"\; state="\{\{state\}\}">T</figure-callout>}}_2\right)\mathrm{,}$$

With T ₁ -T _A = Δ T ₁ and T _A -T ₂ = Δ T ₂ finally follows: $${\mathrm{<figure-callout\; id="1"\; label="\lambda "\; filenames="imgf0001.png,imgf0002.png"\; state="\{\{state\}\}">\lambda </figure-callout>}}_1•<figure-callout\; id="1"\; label="▵\; T"\; filenames="imgf0001.png,imgf0002.png"\; state="\{\{state\}\}">▵\; </figure-callout>T_{}{}_1={\mathrm{<figure-callout\; id="2"\; label="\lambda "\; filenames="imgf0001.png"\; state="\{\{state\}\}">\lambda </figure-callout>}}_2•<figure-callout\; id="2"\; label="▵\; T"\; filenames="imgf0001.png"\; state="\{\{state\}\}">▵\; </figure-callout>T_{}{}_2\mathrm{,}$$

Consequently, if λ ₁ <λ _{2 is} chosen, then Δ T ₁ > Δ T ₂ .

In the application of a centrifuge T _{2 is} kept constant low by means of coolant. Conversely, this means that the temperature inside the boiler T _{1 will have} a much higher temperature difference from the temperature of the contact point T _A.

In order to be able to lower the temperature in the interior of the boiler T ₁ still further, in principle the possibilities are available to reduce the wall thickness s ₁ and s ₂ and / or the boiler wall 1 made of a material with a very high thermal conductivity λ (eg copper or silver), however, the first possibility is technically limited by the functional design of the components and is usually exhausted and the second option is usually not possible for application reasons and the intended use, since for example copper or silver is not chemically inert are.

This leaves the practicable possibility to increase the contact area A. For this purpose, rectangular tubes can be used instead of round tubes, because usually round copper tube is used for the coolant-carrying components and the use of rectangular tube is a significant increase in the contact surface A. However, it is currently technologically impossible, a complete Contact the square pipe wall with the centrifuge boiler. There are always gaps where effectively no heat transfer takes place.

As a solution according to the invention, an additional heat conducting layer is provided on the outer wall of the boiler by the inventors, as in Fig. 2 again in a purely schematic for the resulting and illustrated by the arrows heat flow fragmentary is shown. As a result, an additional Kotaktstelle is inserted with a large contact area.

Unlike the centrifuge kettle after Fig. 1 here is thus adjacent to the interior of the boiler vessel defining inner layer 10 having the thickness of ₁₀ s an additional external boiler layer 11 is applied with the thickness s ₁₁ from good heat conducting material as a boiler outer wall. The cooling line 12 has the thickness s ₁₂ .

For simplification, the assumptions of Fig. 1 in that the wall thicknesses are all equal to s = 1 mm, the cross section of the contact surface A arranged between the outer boiler layer 11 and the cooling line 12 is 1 mm ² and the heat flow outside the contact surface A is equal to zero, that is to say where there is an air gap.

In addition, however, here there is a contact surface B between the boiler layers 10, 11, which is much larger than the other contact surface A. The heat flow is now through the three materials of the inner shell layer 10, the outer shell layer 11 and the cooling line 12 and through the two intermediate contact points A, B, which differ significantly from their size.

According to the continuity principle, Q̇ ₁ = Q̇ _BA = Q̇ ₂ .

Using the formula for the heat flow yields: $${\mathrm{<figure-callout\; id="1"\; label="\lambda "\; filenames="imgf0001.png,imgf0002.png"\; state="\{\{state\}\}">\lambda </figure-callout>}}_1•B\mathrm{•}\left(T_1-T_B\right)={\lambda }_{A-B}•A•\left(T_B-T_A\right)={\mathrm{<figure-callout\; id="2"\; label="\lambda "\; filenames="imgf0001.png"\; state="\{\{state\}\}">\lambda </figure-callout>}}_2•A\mathrm{•}\left(T_A-{\mathrm{<figure-callout\; id="2"\; label="T"\; filenames="imgf0001.png"\; state="\{\{state\}\}">T</figure-callout>}}_2\right)\mathrm{,}$$

und mit T ₁ -T_B=ΔT ₁ und T_B-T ₂=ΔT ₂ zu: $${\lambda }_1•B\mathrm{•}▵T_1={\lambda }_2•\frac{A}{2}•▵T_2\mathrm{.}$$

Further simplifying that the materials of the outer shell 11 and the cooling pipe 12 are the same, and therefore λ _AB = λ ₂ , the relation to: $${\mathrm{<figure-callout\; id="1"\; label="\lambda "\; filenames="imgf0001.png,imgf0002.png"\; state="\{\{state\}\}">\lambda </figure-callout>}}_1•B\mathrm{•}\left(T_1-T_B\right)={\mathrm{<figure-callout\; id="2"\; label="\lambda "\; filenames="imgf0001.png"\; state="\{\{state\}\}">\lambda </figure-callout>}}_2•\frac{A}{2}•\left(T_B-{\mathrm{<figure-callout\; id="2"\; label="T"\; filenames="imgf0001.png"\; state="\{\{state\}\}">T</figure-callout>}}_2\right).$$

and T ₁ -T _B = Δ T ₁ and T _B -T ₂ = Δ T ₂ to: $${\mathrm{<figure-callout\; id="1"\; label="\lambda "\; filenames="imgf0001.png,imgf0002.png"\; state="\{\{state\}\}">\lambda </figure-callout>}}_1•B\mathrm{•}<figure-callout\; id="1"\; label="▵\; T"\; filenames="imgf0001.png,imgf0002.png"\; state="\{\{state\}\}">▵\; </figure-callout>T_{}{}_1={\mathrm{<figure-callout\; id="2"\; label="\lambda "\; filenames="imgf0001.png"\; state="\{\{state\}\}">\lambda </figure-callout>}}_2•\frac{A}{2}•<figure-callout\; id="2"\; label="▵\; T"\; filenames="imgf0001.png"\; state="\{\{state\}\}">▵\; </figure-callout>T_{}{}_2\mathrm{,}$$

That is to say, if λ ₁ <λ _{2 is} selected, Δ T ₁ > Δ T ₂ must therefore again be Δ. However, here a part of the required temperature difference is intercepted by the much larger contact surface B. Or put differently $$B\mathrm{•}<figure-callout\; id="1"\; label="▵\; T"\; filenames="imgf0001.png,imgf0002.png"\; state="\{\{state\}\}">▵\; </figure-callout>T_{}{}_1>\frac{\mathrm{<figure-callout\; id="2"\; label="A"\; filenames="imgf0001.png"\; state="\{\{state\}\}">A</figure-callout>}}{2}•<figure-callout\; id="2"\; label="▵\; T"\; filenames="imgf0001.png"\; state="\{\{state\}\}">▵\; </figure-callout>T_{}{}_2\mathrm{,}$$

In the application of a centrifuge with cooling T _{2 is} kept constant low by means of coolant. However, this means conversely that the temperature inside the boiler T _{1 must} have a higher temperature distance to the temperature of the contact point T _B , but this in turn is lower than in connection with Fig.1 described since B >> A.

Although the principle according to the invention has been described herein with reference to two container layers with different thermal conductivity, it is clear that three or more layers can also be used. These may in particular be anti-corrosion, anti-contamination or the like layers. It is only important that the layer with higher thermal conductivity is arranged on the container outer surface to be cooled. However, one or more further layers can be arranged between the layer with higher and the layer with lower thermal conductivity as well as on the layer with lower thermal conductivity in order to adapt the container to particular conditions of use.

example

Hereinafter, the effects of the invention will be described with reference to a preferred embodiment compared with a comparative example known from the prior art.

A laboratory centrifuge 5415R from Eppendorf AG was used, which has as cooling line 2, 12 a spiral rectangular tube with a width of 9.5 mm, a height of 5.5 mm and a material thickness of 0.5 mm. For this purpose, a serial centrifuge vessel 1 with a diameter of 185 mm, a height of 70 mm and a wall thickness of 1 mm (article No. 5426 123.101-00) from Eppendorf AG was used, which was made of V2A stainless steel (thermal conductivity about 15 W / m * K) and with thermal grease (thermal conductivity about 15 W / m * K) provided in the cooling line 2 was arranged to form the comparative example. For the exemplary embodiment according to the invention, the standard stainless steel centrifuge vessel 10 (article No. 5426 123.101-00) from Eppendorf AG was provided with a 0.1 mm thick copper coating 11 (thermal conductivity about 350 W / m.sup.K), otherwise the experimental setup is the same, ie The centrifuge vessel was connected to the rectangular cooling line 12 by means of thermal paste (thermal conductivity also about 15 W / m * K).

In both cases, the centrifuge 5415R was operated with a conventional rotor F45-24-11 from Eppendorf AG for one hour at a maximum of 13200 rpm. The minimum achievable sample temperature was measured with the temperature meter. The results are recorded in the table. <U> Table </ u> 5415R with centrifuge bowl without Cu coating 5415R with centrifuge bowl with Cu coating Room temperature [° C] 25 26 Sample temperature [° C] 3.9 0.4

The results show that a significantly lower sample temperature is achieved by the copper coating 11 of the centrifuge vessel 10 with the same cooling capacity. By the copper coating 11, the thermal conductivity of the centrifuge tank 10 and thus the efficiency of the cooling system is improved. It is achieved with the same electrical energy consumption, a lower sample temperature.

Thus, it has been demonstrated that the present invention allows much more efficient indirect cooling from the exterior of the container to the interior of the container. The improvement of the heat conduction and the heat transfer of centrifuge boilers results in cooled centrifuges a reduction of the necessary performance of the refrigeration system. Due to the higher efficiency of the centrifuge, a higher rotational speed can be run for the same centrifuging product temperatures and / or the absorbed power of the cooling unit can be reduced with the same centrifuging product temperature and the same rotational speed.

The principle according to the invention is based on the finding that with indirect cooling of a container surface which is larger than the contact surface between the container and the cooling device, the cooling effect can be increased if the container has a layer with higher thermal conductivity in addition to the layer with low thermal conductivity and the layer with higher thermal conductivity is arranged on the container outer surface to be cooled and is in conductive contact with the cooling device. Thus, the cooling capacity is better transferred to the interior of the container to be cooled there Good.

An alternative solution is to make the contact area between the cooling device and the cooled surface of the container at least equal to the cooled container surface. This can be realized by virtue of the fact that the cooling device is part of the layer of the container with greater thermal conductivity.

For this purpose, it can be provided, for example, that the second layer consists of a solid, such as copper or the like, and the cooling device is arranged directly in this layer.

On the other hand, the cooling device can also be arranged in a liquid, gel or the like which is in heat-conducting contact with the layer of lower thermal conductivity and which itself has a higher thermal conductivity. For this purpose, either the container has a layer which has, between itself and the layer with lower thermal conductivity, a cavity which can be filled with a liquid, gel or the like, in which the cooling device is arranged (the thermal conductivity of this further layer is insignificant, as it relates to FIG the cooling device is outside). Or the container does not itself comprise the liquid, gel or the like, but it is provided with the cooling means housed therein in a device in which the container can be arranged to heat the liquid, gel or the like with the layer of low heat conductivity is in managerial contact. For this purpose, for example, the container in the sense of a bath itself, preferably to the edge completely, are immersed in the liquid, gel or the like or the liquid, gel or the like is in contact only with a part of the container outer surface. For transport, care should preferably be taken to ensure adequate sealing of the liquid, gel or the like.

Between the liquid, gel or the like and the layer with low thermal conductivity may also be arranged a further layer with higher thermal conductivity. For example, the liquid, gel or the like may be disposed with the cooling device within a copper sheath which is either integrated directly into the container or provided in the device, where then the container can be brought into direct contact with this copper sheath. This can also achieve the seal. The terms "liquids" and "gels" include both Newtonian fluids and non-Newtonian fluids, sols, dispersions, suspensions, as well as any combination of two or more of these listed substances. In particular, a liquid or gel can be selected from the following group: water, ionic liquids, suspensions of carbon nanotubes, cooling brines, eutectics or eutectic mixtures and similar materials. Antifrogen N, Antifrogen L and Antifrogen SOL) or potassium formate (Antifrogen KF) Furthermore, find ionic liquids, such as 1-ethyl-3-methylimidazolium chloride, 1-ethyl-3-methylimidazolium methanesulfonate, 1-butyl-3-methylimidazolium chloride , 1-butyl-3-methylimidazolium methanesulfonate, 1-Ethyl-2,3-dimethylimidazolium ethylsulfate (sold under the trademark Basionics® BASF SE, 67063 Ludwigshafen, DE) application. Also can be used polyalkylene glycol derivatives.

The advantage of this alternative solution is that the cooling device no longer has to be in direct contact with the container surface to be cooled, possibly mediated by the intermediary of a thermal compound. As a result, there are no such great demands on the accuracy of, for example, the winding geometry of a cooling tube with respect to the container outer contour, which reduces costs.

Claims (8)

A container for indirect cooling of goods in a device, such as centrifuges, stirring devices, cooling devices, such as refrigerators, freezers and the like, wherein the container can be brought into heat-conductive contact with a cooling device of the device and has a container body, characterized in that the container body at least two standing in heat conductive contact container layers (10, 11) having different thermal conductivity, wherein the layer with higher thermal conductivity (11) is arranged on the container to be cooled by the cooling means outside. Container according to claim 1, characterized in that the thermal conductivities differ by a factor of greater than 10, preferably greater than 20, in particular greater than 100. Container according to one of the preceding claims, characterized in that the layer with lower thermal conductivity (10) from a material comprising stainless steel, steel, ceramic, glass, nanomaterial and / or plastic is formed and the layer of higher thermal conductivity (11) of a material aluminum, gold, carbon, copper, magnesium, brass, silver and / or silicon or their alloys. Container according to one of the preceding claims, characterized in that the layer of higher thermal conductivity (11) has a thickness of less than 1 mm, preferably less than 0.5 mm and in particular less than 0.2 mm. Apparatus for the treatment, in particular centrifuging, stirring, cooling or the like of a good, in particular a laboratory centrifuge, a refrigerator, a freezer, a laboratory refrigerator, a laboratory freezer or the like, with a container and a heat-conducting only in some areas with a cooled outer surface of the container Contact standing cooling device for indirect cooling of the arranged inside the container Good, characterized in that the container is designed according to one of the preceding claims. Apparatus according to claim 5, characterized in that the container is surrounded on its side wall and / or its bottom by a tubular, a cooling medium-carrying cooling line (12), which is preferably wound spirally around the side wall and / or on the floor. Method for producing a container according to one of claims 1 to 4, characterized in that the layer with higher thermal conductivity (11) is arranged on the layer with lower thermal conductivity (10) or vice versa. A method according to claim 7, characterized in that the higher thermal conductivity layer (11) is applied to the lower thermal conductivity layer (10) after the lower thermal conductivity layer (10) has substantially the shape of the container or vice versa.

Images