DE102005013926B4 - Device and method for controlling the temperature of a Temperiergutes - Google Patents

Abstract

Device for regulating the temperature of a material to be tempered with a heat exchanger (3) through which a medium (12) flows in a circuit, which is coupled to the heating or cooling surface of a Peltier element (1) and comprises an application tool (5) for receiving the material to be tempered, the Application tool (5) is integrated into the circuit by means of connecting lines (4) at an inlet and an outlet, the medium (12) also flows through it and has a shape adapted to the material to be tempered, characterized in that a temperature measuring device (10.3, 10.4) on each Inlet and at the outlet of the application tool (5) is arranged.

Description

The invention relates to a device and a method for controlling the temperature of a Temperiergutes with a flowed through by a medium in a heat exchanger.

• 1. Anwendungen zur Herstellung pharmazeutischer oder kosmetischer Produkte durch Vervollkommnung der Herstellungstechnologien, zum Beispiel bei der Herstellung von Stoffmischungen in der Pharmazie und in der Kosmetik, die durch eine Behandlung durch eine konkrete Temperaturführung mit höherer Qualität hergestellt werden können. Dies kann beispielsweise durch Abführung von Reibungswärme bei mechanischen Mischtechnologien der Fall sein. Ferner ist auch das Verändern der Konsistenz bei verschiedenen Wärmevorbehandlungs- oder Aufschmelzvorgängen möglich, wodurch erst eine mechanische Verarbeitung ermöglicht wird.
• 2. Anwendungen in der Medizin durch definiertes Kühlen und/oder Erwärmen, zum Beispiel bei medizinischen Heiltherapien, bei denen Folgezyklen mit Kühlungs- und Erwärmungsphasen nach Vorgabe von Temperaturgradienten, analog der Wärme-Kälte-Reize der Kneippschen Wasserbehandlung, verwendet werden.
• 3. Anwendungen im Wellness-Bereich, zum Beispiel zur Hautpflege.

It is a uniform method, in which with an arrangement a temperature in various systems, which can be connected to the arrangement both heat and cool to be able. The invention can be used for a variety of applications. These include in particular:

• 1. Applications for the production of pharmaceutical or cosmetic products by perfection of the production technologies, for example in the production of mixtures in the pharmaceutical and cosmetic, which can be prepared by a treatment by a concrete temperature control with higher quality. This can be the case, for example, by dissipating frictional heat in mechanical mixing technologies. Furthermore, it is also possible to change the consistency during various heat pretreatment or reflow processes, which first enables mechanical processing.
• 2. Applications in medicine by defined cooling and / or heating, for example in medical healing therapies, in which subsequent cycles with cooling and heating phases after the specification of temperature gradients, analogous to the heat-cold stimuli of Kneipp water treatment are used.
• 3. Applications in the wellness sector, for example for skin care.

In the prior art, for stationary or cyclic temperature control predominantly heating elements are used, which are based on the principle of resistance heating, and cooling devices in which a cooled by refrigeration compressors liquid is used.

In DE 297 20 936 U1 is a device for diagnosis and therapy by heat and heat removal on body surfaces described in which a handset is provided with a controllable thermal contact. The thermal contact is controllable by means of a Peltier element fed by a power supply for selective heating or cooling with a frequency of a fraction of a hertz up to a few hertz. The electrical connections of the Peltier element as well as the electrical connections of a temperature sensor in the thermal storage are connected in the vicinity of the Peltier element via a flexible cable connection to a control unit with the power supply.

It is also after DE 299 12 217 U1 a vest for cooling body zones, which is worn under protective suits, in which the wearer is temporarily under great heat stress. Here, cooling zones are provided, in which Peltier elements are arranged, which are supplied with a power source which is integrated in the vest. The cold emitting side of the Peltier elements is attached to the body and the opposite heat radiating side provided with an insulating layer which can store the heat energy over a certain period of application of the vest and thus greatly inhibits the radiation into the suit.

The DE 600 10 890 T2 describes a temperature control apparatus and method used in testing integrated circuits on wafers. The device comprises a heat exchanger with a heat sink and a heating element. The heat sink is kept at a certain temperature by means of a liquid recirculation system. A heating element disposed on the heat sink is used to regulate the temperature of a region corresponding to the heating element to a temperature above the predetermined temperature of the heat sink.

The WO 00/73715 A1 relates to a heat exchanger, in particular for dispensing and air conditioning systems, with a Peltier generator. The Peltier generator is arranged on a highly thermally conductive material block, which comprises a through-line for the medium flowing through and quick-locks for connectable outer leads of other components. The system is suitable both for cooling and for heating the flowing medium. The flowing medium is the temperature.

From the WO 94/00086 A1 a device for tempering therapy pads is known, which comprises a flowed through by a medium heat exchanger and a Peltier element. The pad is integrated into the circuit and has a shape adapted to the body part. A temperature control device is integrated behind the heat exchanger in the circuit.

A further development of this system is in the US 5 871 526 A disclosed. A programmable temperature controller can automatically perform pre-programmed cooling and heating cycles of various lengths and temperatures.

The US 4,962,761 A describes a generic thermal bandage. A temperature sensor is provided in the circulation of the medium for the purpose of heating and monitoring. Another Temperature sensor can determine the skin temperature and be integrated into the control loop.

From the DE 10 2004 023 598 A1 a cooling device is known which is suitable for cooling a body part. The device comprises a control device, a body cooling part and a connecting means, which form a closed cooling circuit during operation. The temperature control can be done by specifying a target temperature of the refrigerant and the detection of an actual temperature at the heat exchanger and / or on the body part.

In the known heating and cooling systems is disadvantageous that a complex control device is required to achieve the desired effects. A defined temperature control with inert conditions, as required, for example, when mixing different substances for medical and pharmaceutical applications is not known.

The invention has for its object to improve a generic device to the effect that an optimal heat transfer for changing applications of different forms of Temperiergutes and an inert temperature detection is possible. In addition, a method for temperature control is to be provided in such a device.

According to the invention, the object is achieved with a device which has the features specified in claim 1 and with a method which comprises the features specified in claim 17.

Advantageous embodiments are specified in the subclaims.

• – ein vorwiegend für den zyklisch geschalteten Betrieb des Peltierelementes verwendeter massereicher Wärmetauscher,
• – ein für den stationären Betrieb des Peltierelementes geeigneter massearmer Wärmetauscher und
• – ein vorwiegend für den Einsatz von genauen Festtemperaturniveaus geeigneter Latentspeicher.

The Peltier generator supplies one of the respective application thermally adapted heating or cooling energy. The heat transfer from the Peltier element to the heat exchanger and the temperature control to the application tools via a liquid or gaseous heating / cooling medium in Umwälzprinzip. The application tools are connected to the heat exchanger via a drop-free or gaseous tight connection system. The functional characteristics are determined by the thermal properties of the assemblies, which can be very accurately calculated and regulated by means of an electronic, computer-aided heat quantity regulator. By reversing the direction of the current, you can choose between the cooling and heating modes. The electrical power is preferably supplied to the Peltier element via an AC / DC power supply, an accumulator or a solar module. By defined cooling of the hot side, a heat resistance of the heat sink attached to the Peltier element preferably less than 0.2 K / W, the cooling performance is optimized. In the case of heating, the heat sink dissipates the cooling capacity. On the Peltier element, a heat exchanger is mounted so that an optimal heat transfer is possible. Depending on the control principle, the heat exchangers are used in three versions. These are:

• A massive heat exchanger used predominantly for the cyclically operated operation of the Peltier element,
• - A suitable for stationary operation of the Peltier element low mass heat exchanger and
• A latent storage tank which is predominantly suitable for the use of precise fixed temperature levels.

The heat exchangers should be designed in an advantageous standardized manner.

Preferably, the cooling or heating medium is moved via a circulation pump and thus the energy is transported via connecting lines to the application tool. A special form of the connecting lines is the capillary line. The circulation pump is advantageously constructed so that the electrical part is thermally separated from the mechanical pump part in order to avoid a thermal influence of the cooling / heating medium. The control engineering specification of the cooling and heating energy offers the possibility of medical applications, since heat quantity / heat output and thermal gradient can be specified.

• 1. Durch die Verwendung von Peltierelementen als Generator sowohl von Wärme- als auch von Kälteenergie wird über einen Anwendungstool eine gute Anpassung an die erforderliche Erwärmung oder Kühlung des Temperiergutes ermöglicht. Es besteht die Möglichkeit einer dynamischen, stufenlosen Stellbarkeit der zu generierenden Wärme- und Kälteenergie. Ein Kontakt mit den stromführenden Leitern durch Keramikheiz- und – kühlplatten wird vermieden. Da die Anordnung in kleinen Abmessungen gefertigt werden kann und für die Kühlung nur ein geringer Medienaufwand erforderlich ist, ist auch ein mobiler Einsatz möglich.
• 2. Aufgrund des flächigen oder punktförmigen und formschlüssigen Kontaktes mit dem Temperiergut bzw. dessen Behältnis wird eine energetisch optimierte Wärmeübertragung gewährleistet.
• 3. Durch den optimierten Wärmeübergang kann die Temperatur des Temperiergutes durch eine stationäre Konstantregelung der Kupfer-Verteilernetztemperatur oder eines flexiblen Wärmeflächenleiters mit einer einfachen und preiswerten 2- oder 3-Punkt-Regelung geregelt werden. Hierzu ist die Messung der Kupfer-Verteilernetztemperatur oder die Messung der Vor- und Rücklauftemperatur ausreichend. Daraus ergeben sich deutliche Vorteile für eine vereinfachte Adaption des flexiblen Flächenmoduls sowie der Sicherstellung inerter Bedingungen, die in der Medizin und pharmazeutischen Industrie essentiell notwendig sind. Hierfür muss die zu regelnde Temperatur indirekt ermittelt werden.

The invention is characterized by a number of advantages. These include in particular:

• 1. By using Peltier elements as a generator of both heat and cold energy, a good adaptation to the required heating or cooling of the temperature-controlled material is made possible by an application tool. There is the possibility of a dynamic, stepless adjustability of the heat and cold energy to be generated. Contact with the live conductors by ceramic heating and cooling plates is avoided. Since the arrangement can be made in small dimensions and only a small amount of media is required for the cooling, a mobile use is possible.
• 2. Due to the flat or punctiform and positive contact with the Temperiergut or its container an energetically optimized heat transfer is ensured.
• 3. Due to the optimized heat transfer, the temperature of the temperature control can be controlled by a stationary constant control of copper distribution network temperature or a flexible heat transfer surface with a simple and inexpensive 2 or 3-point control. For this the measurement of the copper distribution network temperature or the measurement of the supply and return temperatures is sufficient. This results in clear advantages for a simplified adaptation of the flexible module and the assurance of inert conditions, which are essential in the medical and pharmaceutical industries. For this, the temperature to be controlled must be determined indirectly.

The invention will be explained in more detail below with reference to an embodiment. In the accompanying drawing show:

1 : a schematic diagram of the combined heating and cooling system;

2 : a schematic structure of a combined heating and cooling system with plug-in system;

3 : a combined heating and cooling system with a flexible application tool;

4 a block diagram of the electrical function groups; and

5 : the electrical equivalent circuit diagram of the heating and cooling controller without direct temperature measurement.

• – Peltierelement 1 mit Kühlkörper 2
• – Wärmetauscher 3
• – Kapillar-Verbindungsleitungen 4
• – Anwendungstool 5
• – Heizregister 8

sowie einem Lüfter 6 und einer in der Figur nicht dargestellten Regeleinrichtung 13.This in 1 shown combined heating and cooling system consists of the system components

• - Peltier element 1 with heat sink 2
• - Heat exchanger 3
• - Capillary connection lines 4
• - Application Tool 5
• - Heating register 8th

as well as a fan 6 and a control device, not shown in the figure 13 ,

2 shows a detailed example. The heating and cooling system contains at least one Peltier element 1 to which one of a control device, not shown here 13 predetermined electrical DC voltage is applied and thus depending on the direction of heat or cooling energy is delivered to the heat exchanger. Below the Peltier element 1 there is a heat sink 2 that with a fan 6 and a heater 8th is coupled. Depending on the use of a specific Peltier element, the temperature at the heat exchanger can be lowered starting from the room temperature cooling of the heat sink or increased to the maximum permissible temperature of the Peltier element depending on the preheating of the heat sink and electrical reversal. The temperature gradient in the heating mode is determined by the preheating. Depending on the heat sink temperature and the level of the current / voltage values, the temperature values can be infinitely varied from -20 ° C to + 100 ° C. From the Peltier element 1 is the heat or cold energy to a heat exchanger 3 transfer. The heat exchanger 3 is to ensure a good energy balance of an insulating body 9 surround. In the case shown, the heat exchanger 3 a fluid chamber that is part of a hydraulic system. The hydraulic system includes a fluid circulation pump 7 , a surge tank 11 and an application tool 5 , The equalizing vessel 11 here consists of a transparent container, which also serves as a level indicator and for filling the hydraulic system with the medium 12 serves. The application tool 5 contains a capillary system and is via the drop-free connectors 4.1 and 4.2 releasably connected to the hydraulic system. The capillary system is used for uniform fluid transport in the application tool 5 and forms a heat branching network. The uniform surface distribution of the heating and cooling energy as well as the better heat transfer to the temperature control material can be achieved by a flexible copper mesh made of ultrafine strands or a flexible heat transfer conductor, which can be used in the application tool 5 is integrated, supported. Embodiments are also possible in which a selective energy transfer from the application tool 5 on the Temperiergut by the arrangement of good thermal conductivity metal tips on the application tool 5 is realized. For temperature measurement are temperature measuring points 10 on the surfaces of the Peltier element 1 as well as at the inlet and outlet of the application tool 5 appropriate.

The fluid chamber can be formed both in the form of a massive body that serves as a heat storage (cyclic operation), or as a massearmes component that serves as a flow chamber for a liquid or gaseous medium 12 serves, with which the heat transport takes place. In this mode, a static operation is advantageous.

The arrangement allows different application tools 5 to connect to the fluid chamber. Particularly suitable for this purpose are rigid modules or flexible surface modules. The connection of rigid modules makes it possible to realize cooling and heating plates on which the temperature control material is placed directly or in vessels.

In 3 an embodiment is shown with an elastic surface module. There is the application tool 5 from a dressing that is placed around the temperature to be heated or cooled. In the application tool 5 a capillary and a copper distribution network are incorporated. Due to the flexible adaptation of the form of the dressing to the tempering material optimal heat transfer conditions are achieved. The elastic surface module may advantageously consist of a plastic film bag, in which the flow channels are made by film welding joints. The equalizing vessel 11 consists here of a stretchable tubing.

4 explained on the basis of a block diagram, the electrical operation of the arrangement. The central element is the one with the Peltier elements 1 coupled control device 13 that from the PSU 14 is supplied and the circulation pump 7 , the heating register 8th and the cooling fan 6 controls. It is with a safety circuit 15 to avoid malfunctioning operating cases, such as thermal overload of the Peltier elements, as well as with the temperature sensors 10 and a PC interface 16 connected.

The regulation of the Peltier element 1 can be done by different methods.

A first variant is the use of a stationary controller for cyclic control. The stationary controller is a 2- or 3-point controller which, depending on the control deviation, provides the cooling or heating output for the Peltier element 1 provides. The regulation takes place by cyclically switching on and off the power supply to the application tool 5 , The regulator expediently consists of a switch-off relay for the first point, that is, there is neither heating nor cooling, as well as two change-over switch relay for the switch of the direction reversal of the supply voltage of the Peltier element 1 , The to the respective Peltier element 1 adapted supply voltage and current limiting is supplied via a separate voltage source, which is possible with a rechargeable battery, a solar module or a power supply unit.

As a cost-effective variant, it is also possible to achieve stationary operating conditions by fixed parameters without control of the operating temperature.

A 2 , Variant consists in real-time control with a transient controller. In this case, the exact temperature gradient at the transfer point to the temperature control material is determined by measuring the copper distribution network temperature or the temperature of the thermal surface conductor. By measuring the fluid temperatures at the input and output of the application tool 5 the heat and cold energy absorbed by the temperature can be calculated. With a cooling or heating process carried out in advance with the temperature control material, its heat capacity is determined. Thus, the temperature profile in the temperature can be determined without direct measurement and the feed heat flow of the Peltier element 1 be precisely regulated.

It is also possible to operate the arrangement of the transient temperature control based on the Peltier temperatures. This is done by defined variation of the supply voltage and thus of the Peltier element 1 absorbed electric current and by measuring the temperature values on the cold and hot Peltierelementoberfläche 1.1 and 1.2 the generated heating and cooling energy (feed heat flow) determined. By experimental determination of the almost constant heat transfer resistances, the temperature curves can be determined in advance as a function of the feed heat flow. This makes it possible to realize a processor-based feedforward control for a desired dynamic or transient temperature control.

The variants described for controlling the heat and cooling capacity are in 5 explained on an electrical equivalent circuit diagram in which the heat or cold is controlled by a power controller processor-based. The determination of the temperature takes place here via the energetic behavior of the Peltier element 1 so that a direct measurement in the application tool is not required. This can enable inert conditions for medically clean technologies, which is a fundamental advantage for medical applications.

The heat output of the Peltier element 1 on the warm surface arises from the relationship

Wärmeleitungswiderstand R_W = Δx / λ·A Peltierkoeffizient Π_AB = α·T The heat output of the Peltier element 1 on the cold side of the relationship

Heat conduction resistance R _W = Δx / λ · A Peltier coefficient Π _AB = α · T

LIST OF REFERENCE NUMBERS

R_el

Elektrischer Widerstand des Peltierelementes

I

Elektrischer Strom durch das Peltierelement

A

Peltierelementoberfläche

Δx

Dicke des Peltierelements

α

Seebeck-Koeffizient/Thermokraft

λ

Wärmeleitfähigkeit, z. B. Wismut-Tellurid: 1,3 W/(K*m)

τ

Thompsonkoeffizient

Π_AB

Peltierkoeffizient

ΔT

Temperaturdifferenz zw. warmer und kalter Peltierelementoberfläche

T

Absolute Temperatur

T_W

Absolute Temperatur der warmen Peltierelementoberfläche

T_K

Absolute Temperatur der kalten Peltierelementoberfläche

T_CU

Absolute Temperatur des Kupfer-Verteilernetzes

T_TG

Absolute Temperatur des Temperiergutes

T_WTE

Absolute Temperatur Wärmetauschereintritt

T_WTA

Absolute Temperatur Wärmetauscheraustritt

Q_KK

Wärmekapazität Kühlkörper

Q_KF

Wärmekapazität Kühlflüssigkeit

Q_TG

Wärmekapazität Temperiergut

R_WÜK

Wärmeübergangswiderstand Kühlflüssigkeit

R_WüL

Wärmeübergangswiderstand Kühlluft

R_WKF

Wärmeleitungswiderstand Kühlflüssigkeit (Wärmetauscher)

R_WTG

Wärmeübergangswiderstand Behälter Temperiergut

R_wcu

Wärmeübergangswiderstand Cu-Verteilernetz

R_W

Wärmeleitungswiderstand

Fig. 5

R _el

Electrical resistance of the Peltier element

I

Electric current through the Peltier element

A

Peltier element surface

Ax

Thickness of the Peltier element

α

Seebeck Coefficient / thermopower

λ

Thermal conductivity, z. B. bismuth telluride: 1.3 W / (K * m)

τ

Thompsonkoeffizient

Π _AB

Peltier coefficient

.DELTA.T

Temperature difference between warm and cold Peltierelementoberfläche

T

Absolute temperature

T _W

Absolute temperature of the warm Peltier element surface

T _K

Absolute temperature of the cold Peltier element surface

T _CU

Absolute temperature of the copper distribution network

_TG

Absolute temperature of the temperature control material

T _WTE

Absolute temperature heat exchanger inlet

T _WTA

Absolute temperature heat exchanger outlet

_QKK

Heat capacity heat sink

Q _KF

Heat capacity of coolant

Q _TG

Heat capacity temperature product

R _WÜK

Heat transfer resistance coolant

R _WüL

Heat transfer resistance cooling air

R _WKF

Heat conduction resistance of cooling liquid (heat exchanger)

R _WTG

Heat transfer resistance Container Temperiergut

R _wcu

Heat transfer resistance Cu distribution network

R _W

Heat conduction resistance

Claims (19)

Device for controlling the temperature of a product to be tempered with one of a medium ( 12 ) flowed through in a heat exchanger ( 3 ), which with the heating or cooling surface of a Peltier element ( 1 ) and an application tool ( 5 ) for receiving the tempering material, wherein the application tool ( 5 ) by means of connecting lines ( 4 ) is integrated into the circulation at an inlet and an outlet, also from the medium ( 12 ) is flowed through and has a Temperiergut adapted form, characterized in that in each case a temperature measuring device ( 10.3 . 10.4 ) at the inlet and outlet of the application tool ( 5 ) is arranged. Apparatus according to claim 1, characterized in that the connecting lines ( 4 ) Plug connections ( 4.1 . 4.2 ) exhibit. Apparatus according to claim 1 or 2, characterized in that the medium is a liquid and the heat exchanger ( 3 ) is a fluid chamber. Apparatus according to claim 3, characterized in that in. The connecting lines a circulating pump ( 7 ) is arranged. Device according to claim 3 or 4, characterized in that the application tool ( 5 ) a capillary system ( 5.1 ) for fluid transport. Device according to one of claims 1 to 5, characterized in that the application tool ( 5 ) for improving the heat transfer to or from the tempering further comprises: - a flexible heat transfer ladder or - a copper net made of ultrafine strands or - heat-conductive metal tips. Device according to one of claims 1 to 6, characterized in that the application tool ( 5 ) consists of flexible material. Device according to claim 7, characterized in that the application tool ( 5 ) is an elastic surface module, which can be laid as a dressing around the temperature. Apparatus according to claim 8, characterized in that the elastic surface module is a plastic film bag, in which flow channels are produced by film welding joints. Device according to one of claims 1 to 9, characterized in that the Peltier element ( 1 ) on a heat sink ( 2 ) is arranged. Apparatus according to claim 10, characterized in that the heat sink ( 2 ) is coupled to a heating and / or cooling device. Device according to one of claims 1 to 11, characterized in that in the circulation of the medium, a surge tank ( 11 ) is arranged. Apparatus according to claim 12, characterized in that the expansion tank ( 11 ) serves as a level indicator and / or refill. Apparatus according to claim 12, characterized in that as a compensating vessel ( 11 ) consisting of a stretchable material heat exchanger ( 3 ) serves. Device according to one of claims 3 to 14, characterized in that at least one further temperature measuring device is arranged on the fluid chamber. Device according to one of claims 3 to 15, characterized in that at least the fluid chamber is provided with a thermal insulation. A method for temperature control in a device according to claim 1, characterized by the following steps: - calculation and control of the application thermally adapted heating or cooling energy via an electronic, computerized heat quantity regulator; - Generation of heating or cooling energy with a Peltier generator and transfer to the application tool ( 5 ). A method according to claim 17, characterized in that for temperature control, the temperatures of the medium ( 12 ) at the inlet and outlet of the application tool ( 5 ) are measured and used to calculate the heat and cold energy absorbed by the temperature. A method according to claim 18, characterized in that the temperature gradient at the transfer point between Temperiergut and application tool ( 5 ) and included in the scheme.

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