DE202006005668U1 - Tempering device for sample containers, especially for use in laboratory tests, comprises a housing with an opening for the container, using a medium flowing in a closed circuit through the housing and round the container - Google Patents

Abstract

A tempering device (10) (especially for laboratory tests), comprising a housing (11) through which a medium flows, with an opening (19) for a sample container (16), in which the medium is passed through the housing (11) in a closed circuit and flows at least partly round the container (16).

Description

The The invention relates to a temperature control device, in particular for laboratory tests, consisting of a housing with an opening for a sample container, wherein the housing flows through a medium becomes.

at Laboratory tests will be the sample material from different establish often heated to relatively accurate temperatures or cooled. in this connection can sample container be used with different dimensions.

Generic temperature control exist from a housing, in its surface a round opening is present, which serves to accommodate sample containers in a round shape. These sample containers have to made of thermally conductive Material exists, so that a rapid heat transfer can take place. Such tempering are usually closed containers with an inlet opening and an outlet opening for circulating a Temperature fluid. These liquids when heating through a separate thermostatic bath or for cooling by means of a separate cooling unit brought to a certain temperature. Such devices are relatively expensive to manufacture and relatively warming or cooling sluggish, which makes it impossible is to set the temperatures with high accuracy.

Of the The invention is therefore based on the object, a tempering to create, which allows a very accurate and rapid tempering of sample vessels.

These Task is characterized in a device of the type mentioned by solved, that the medium is guided in a closed circuit within the housing and the sample container at least partially flows around. Further advantageous embodiments of the invention will become apparent from the dependent claims. Of the particular advantage of the embodiment of the invention is that in a closed circuit formed a narrow volume is inside the case located and thus by means of a low energy output for heating or cooling allows a temperature. An inserted sample container is thus flows around at least in the lower area and can thus on the inside of the housing set temperature can be brought within a very short time.

to Another embodiment of the invention is provided that a second Cycle for a medium is provided to the temperature of the first circuit to influence. This influence can be indirect or immediate carried out be, for example, a cooling of the first cycle. The temperature control device according to the invention is equipped with a heating and / or cooling device, which are provided for temperature control, wherein a temperature control device both can control the heating device as well as the cooling device, at the preset temperature by means of a potentiometer or the like electronic components to a set target value. For this purpose, sensors are provided, for example, received in the sample container could be, it is possible as well inside the case Provide sensors that determine the temperature and control of the temperature control unit can be used.

Preferably is the case as a closed container trained and directly heated and / or cooled. Here, the temperature control unit within of the housing or a flanged housing part be arranged. As a preferred heater is a halogen bulb However, there is the possibility of other sources of heat, the above the temperature control unit be controlled to provide. As a cooling device is preferably However, a Peltier element could also be used to provide other cooling devices which are also over the temperature control unit is activated become.

The Peltier element stands here on one side in a thermal Contact with the first circuit and on the other side in one thermal contact with a second circuit to a temperature influence the first cycle over to enable the second cycle. additionally are both circuits with a fan equipped to ensure air circulation, in particular in the first circuit, so that the sample container is constantly flowing around. Another fan can, for example be integrated in the second cycle to create a flow to create one side of the Peltier element. For this has the Peltier element on both sides of a strand cooling body, which directly through the medium of the first and the second heating circuit is flowed around. The particular advantage of this solution is that possibly different Media can be used.

About one rod-shaped Temperature sensor, which can be inserted through the lid into the sample container is, can be a temperature monitor be made with the temperature sensor of course with connected to the temperature control unit which is to control the fan and the halogen bulb and the cooling device is provided.

The sample container itself can through the Opening of the housing are inserted and sits directly on the housing bottom or is thermally separated by an insulating layer of the housing in addition, so that unintentional cooling or heating effects are avoided by the ambient air. For this reason, the opening for the sample container is additionally equipped with a sealing ring which seals the gap between the sample container and the opening so far that the circulation of the temperature control can be kept at a constant value.

In an embodiment the temperature control device according to the invention is in the lateral interior of the container a fan with a mounted halogen bulb provided, its heat radiation from the fan is detected and directed directly against the sample container.

On the other side of the container is an opening provided, thereby cooling Air blown into the unit can be. This cool Air is passed through a cooling system on this side of the tank achieved with a Peltier element. If necessary, this Peltier element could also be reversed to the heating element to the temperature in the container to increase. Switching from cold to warm, however, will take a relatively long time whereby no accurate temperature setting would be possible. That's why preferably a one-sided use of the Peltier element as a cooling device used.

• 1. Die Kühlung wird in dem im Kühlsystem vorhandenen Strang-Kühlkörper gespeichert und ist sofort vorhanden, wenn die Lüfter der Kühlung eingeschaltet werden.
• 2. Durch das Zusammenspiel von Heizlüfter und Kühllüfter ist eine genaue Temperatureinstellung von bis zu +/- 0,1° C möglich. Ein im zu temperierenden Probenbehälter am Deckel angebrachter Präzisions-Temperatursensor steuert das kurzzeitige Umschalten von Heizen auf Kühlen.
• 3. Mit dem Peltier-Kühlsystem ist es ebenfalls möglich das Probengefäß auf eine Temperatur einzustellen, welche niedriger ist als die vorhandene Umgebungstemperatur zum Beispiel in südlichen Ländern oder in der heißen Jahreszeit.

This results in several advantages:

• 1. The cooling is stored in the existing in the cooling system strand heatsink and is immediately available when the cooling fans are turned on.
• 2. The combination of fan heater and cooling fan allows a precise temperature setting of up to +/- 0.1 ° C. A precision temperature sensor attached to the lid to be tempered controls the short-term switching from heating to cooling.
• 3. With the Peltier cooling system it is also possible to set the sample vessel to a temperature which is lower than the existing ambient temperature, for example in southern countries or in the hot season.

Of the Precision Temperature Sensor is connected to a thermostat with digital display. In the control panel of the temperature control unit is at least a potentiometer for precise adjustment of wattage of the fan heater and the cooling capacity of the Peltier element installed. This possible change in performance is very important and dependent from the existing ambient temperature.

At the Cool the cold air is directed against and around the sample vessel and passes through the existing side channel back into the cooling system, so that the air faster on the needed Temperature can be lowered and at higher ambient temperature no cold air can escape.

An application example:
For measuring the viscosity of liquids, for example in paints and varnishes, DIN NORM 53 211 and ISO NORM 2431 require the outflow time to be determined using a standard aluminum flow cup at a temperature of 23 ° C and a tolerance of +/- 0 , 2 ° C must be measured. This is readily possible with this device according to the invention.

In order to the flow time with a flow cup located in the device as a sample container can be measured, a closable opening is provided in the bottom of the housing, which especially for open this purpose can be.

in the The following will be a preferred embodiment of the invention with reference to the attached drawings explained in more detail.

It shows

1 a perspective view of a temperature control device according to the invention for a sample container, not shown,

2 a cross section through the temperature device according to 1 and

3 a longitudinal section through a portion of the temperature device with receiving plate and sample container with lid.

1 to 3 show a temperature device 10 for tempering sample containers 16 , The temperature device 10 has a rectangular in plan floor made of plastic housing 11 on, that on a side surface 12 with an inlet opening 13 and a side surface 14 with an outlet opening 15 is provided for the supply and removal of a tempering air. In order to achieve a good heat transfer it is necessary that the sample container 16 has at least the same dimension as the height 17 of the housing 11 and on the floor 18 can be put on. The sample container 16 should also have the same diameter as the opening 19 in the cover plate 20 , When the sample container 16 smaller than the opening 19 can, by means of a around the top of the sample container 16 attached rubber cuff 21 The gap 22 be closed. This prevents that the tempered air can escape. To heat loss in the sample container 16 to prevent is a lid 23 of plastic on the opening of the sample container 16 put on and with a weight as a handle 35 Mistake. The height in the a rod-shaped precision temperature sensor 24 in the sample container 16 protrudes into it, is by means of a cable guide grommet mounted in the lid 25 adjustable in rubber.

In the interior of the housing 11 is at the front 26 a fan 27 with one or more small halogen bulbs 28 attached as a heating element. halogen bulbs 28 have the advantage that the heat radiation is very high and that the heating elements are closed, in the event that a flammable material in the sample container 16 located.

At one in the side surface 12 located inlet opening 13 is the output of a cooling system 29 arranged. One in the cooling system 29 existing Peltier element 30 cools a strand cooling body 31 , The fan 32 promotes the air through one in the side surface 14 arranged outlet opening 15 over a closed connecting pipe 33 through an opening 34 and the extruded heat sink 31 and then through the inlet opening 13 back into the interior of the temperature device 10 , This way of the medium forms the first cycle, whereby air is used as medium.

The second cycle, however, is through an inlet opening 36 and an exit opening 37 of the housing 11 formed, wherein in this second circuit a fan 38 is arranged, which the air flow over a second strand cooling body 39 leads, which also with the Peltier element 30 in thermal contact. It was ensured that by the Peltier element 30 a direct connection between the first and second circulation is excluded.

3 shows a sectional side view of an inserted sample container 16 passing through the opening 19 in the case 11 protrudes and sits on the ground. The medium used for cooling or heating is indicated by horizontal lines.

10

tempering

11

casing

12

side surface

13

inlet port

14

side surface

15

outlet

16

sample container

17

height

18

ground

19

opening

20

cover plate

21

rubber sleeve

22

gap

23

cover

24

Precision Temperature Sensor

25

Kabelführungstülle

26

front

27

Fan

28

halogen bulb

29

cooling system

30

Peltier element

31

Extruded heatsinks

32

Fan

33

connecting pipe

34

opening

35

Handle

36

inlet opening

37

outlet opening

38

Fan

39

Extruded heatsinks

Claims (13)

Tempering device ( 10 ), in particular for laboratory tests, consisting of a housing ( 11 ) with an opening ( 19 ) for a sample container ( 16 ), the housing ( 11 ) is flowed through by a medium, characterized in that the medium in a closed circuit within the housing ( 11 ) and the sample container ( 16 ) flows at least partially. Tempering device ( 10 ) according to claim 1, characterized in that a second circuit is provided for a medium in order to influence the temperature of the first circuit. Tempering device ( 10 ) according to claim 1 or 2, characterized in that a heating and / or a cooling device is provided for influencing the temperature, which are controllable by a temperature control device. Tempering device ( 10 ) according to one or more of claims 1, 2 or 3, characterized in that sensors ( 24 ) are provided for determining the temperature and control of the temperature control device. Tempering device ( 10 ) according to one or more of claims 1 to 4, characterized in that the housing ( 11 ) is designed as a closed container directly heated and / or cooled. Tempering device ( 10 ) according to one or more of claims 1 to 5, characterized in that the temperature control device within of the housing ( 11 ) or a flanged housing part is arranged. Tempering device ( 10 ) according to claim 3, characterized in that a halogen bulb ( 28 ) and as a cooling device a Peltier element ( 30 ) is provided. Tempering device ( 10 ) according to one or more of claims 1 to 7, characterized in that the Peltier element ( 30 ) is in thermal contact with the first circuit on one side and in thermal contact with the second circuit on the other side. Tempering device ( 10 ) according to one or more of claims 1 to 8, characterized in that the Peltier element ( 30 ) on both sides with a heat sink ( 31 . 39 ), which are each associated with a circuit is equipped. Tempering device ( 10 ) according to one or more of claims 1 to 9, characterized in that both circuits a fan ( 32 . 38 ) exhibit. Tempering device ( 10 ) according to one or more of claims 1 to 10, characterized in that at least one rod-shaped temperature sensor ( 24 ) through a lid ( 23 ) in the sample container ( 16 ) and is electrically connected to the temperature control unit, which for controlling the fan ( 32 . 38 ) and the halogen bulb ( 28 ) is provided. Tempering device ( 10 ) according to one or more of claims 1 to 11, characterized in that the sample container ( 16 ) in the opening of the housing ( 11 ) and preferably on the ground ( 18 ) of the housing ( 11 ) is seated. Tempering device ( 10 ) according to one or more of claims 1 to 12, characterized in that the opening ( 19 ) for the sample container ( 16 ) has a seal.