Temperature control device, in particular for laboratory cabinets, air conditioning cabinets, refrigeration cabinets or environmental simulation cabinets

Abstract

The invention relates to a temperature control device (10-1, 10-2, 10-3) having a cooling circuit (20) with a refrigeration carrier, the cooling circuit (20) having a refrigeration source (22), a consumer heat exchanger (24) located in a return flow (22b) of the refrigeration source (22), and a pump (26), the refrigeration source (22) being part of a second heat exchanger (50), the consumer heat exchanger (24) being part of the return flow (22b) of the refrigeration source (22), and the pump (26) being part of the second heat exchanger (50). An external refrigeration circuit (60) is coupled with refrigerant to the cooling circuit (20) through the second heat exchanger (50), and the external refrigeration circuit (60) is provided with a compressor (62), a condenser (64) and a first throttling component (66).

Description

TECHNICAL FIELD

[0001] The invention relates to a temperature control device, in particular for a laboratory cabinet, an air-conditioning cabinet, a refrigeration cabinet or an environmental simulation cabinet. BACKGROUND

[0002] It is known to adjust the temperature in a sample chamber of a laboratory cabinet, an air-conditioning cabinet, a refrigeration cabinet or an environmental simulation cabinet in a desired manner using a temperature control device for temperature control of the sample chamber.

[0003] DE 102 04 04 737 A1 discloses a device for controlling a constant primary flow temperature in a liquid cooling and in a heat pump, wherein a storage circuit for energy transport containing a storage liquid is provided, which is connected to a cooling / heating circuit and to a consumer, respectively, wherein a storage container is integrated into the storage circuit, and wherein, in the storage circuit, in connection with the cooling / heating circuit, a buffer storage through which the storage liquid can flow in one direction is connected in series to the consumer, and, in parallel to the buffer storage, an adjustable connection in terms of its flow rate is provided between the inlet line and the outlet line of the buffer storage. This device makes it possible to keep and adjust the primary flow temperature constant, and, if desired, to limit the cooling or heating power at the consumer. Here, the buffer storage acts as an energy store and extracts and stores energy as required. The downtime of the compressor can be bridged without the primary flow temperature rising or falling. However, the buffer storage is complex and requires additional energy. SUMMARY

[0004] It is an object of the present invention to provide a temperature control device with which more efficient temperature control can be achieved.

[0005] According to the invention, this object is achieved by a temperature control device having the features of claim 1.

[0006] Advantageous embodiments and refinements of the invention are specified in the dependent claims.

[0007] The temperature control device according to the invention has a cooling circuit with a refrigeration carrier, wherein the cooling circuit has a refrigeration source, a consumer heat exchanger in the return flow of the refrigeration source, and a pump, wherein the refrigeration source is part of a second heat exchanger through which an external refrigeration circuit is coupled to the cooling circuit with a refrigerant, the external refrigeration circuit having a compressor, a condenser and a first throttling member. The compressor is a speed-regulated compressor. By arranging the compressor in combination with the throttling member in the external refrigeration circuit, a reduction in the required energy is achieved, since the provision of the required refrigeration can be adapted to the situation. As a result, a refrigeration store or buffer store, which has to be maintained with energy, in particular in the form of a cooled refrigeration carrier, can be dispensed with.

[0008] Preferably, the compressor is arranged in the backflow of the second heat exchanger and the first throttling member is arranged in the headflow of the second heat exchanger. This arrangement enables cooling.

[0009] Advantageously, the compressor is designed as a variable speed compressor. This enables high energy efficiency.

[0010] According to a particularly preferred embodiment of the application, the first throttling member is designed as a solenoid valve, in particular with a capillary, or as a continuous valve. Solenoid valves are particularly robust and continuous valves can be controlled particularly well, preferably steplessly, so that particularly fine metering is achieved.

[0011] A particularly advantageous design of the application provides that the second throttling member and the evaporator are arranged in parallel to the first throttling member and the second heat exchanger. Such an evaporator can enable dehumidification of a laboratory cabinet, an air conditioning cabinet, a refrigeration cabinet or an environmental simulation cabinet, in particular target dehumidification by means of the second throttling member. The second throttling member can in particular be controlled independently of the first throttling member.

[0012] Preferably, the evaporator is designed as a blow-through evaporator. Such an evaporator is easy to manufacture and cost-effective and can in particular be designed in a space-saving manner.

[0013] Preferably, the second throttling member is designed as a solenoid valve, in particular with a capillary, or as a continuous valve. Solenoid valves are particularly robust and continuous valves can be controlled particularly well, preferably steplessly, so that particularly fine metering is achieved.

[0014] Advantageously, the return injection of refrigerant into the compressor takes place by means of a third throttling member, which is in particular arranged in parallel to the first throttling member and the second heat exchanger. The return injection can take place in a regulated manner by means of the third throttling member, so that in particular the required amount of refrigerant is recovered and used, so that cooling of the compressor is achieved. The third throttling member is in particular controlled independently of the first throttling member and, if present, independently of the second throttling member.

[0015] Preferably, the third throttling member is designed as a solenoid valve, in particular with a capillary, or as a continuous valve. Solenoid valves are particularly robust and continuous valves can be controlled particularly well, preferably steplessly, so that particularly fine metering is achieved.

[0016] The first throttling member and / or the second throttling member and / or the third throttling member is preferably designed to be adjustable.

[0017] According to a preferred embodiment of the application, the second heat exchanger is configured as a plate heat exchanger or as a coaxial tube heat exchanger. Such heat exchangers can be configured compactly and achieve good heat transfer.

[0018] Preferably, the cooling circuit has a non-flammable fluid, such as a water-glycol mixture, a silicone oil or a salt solution, as refrigerant carrier. Thereby, the respective safety requirements can be met in accordance with the requirements for the sample chamber of the respective laboratory cabinet, air conditioning cabinet, refrigeration cabinet or environmental simulation cabinet.

[0019] According to an advantageous refinement of the application, the external refrigeration circuit has a hydrocarbon, in particular propane or isobutane, or CO2 as refrigerant. Such refrigerants are a climate-friendly alternative to halogenated refrigerants, since they do not have a significant impact on the greenhouse effect, wherein, however, due to the flammability, higher safety requirements are placed on the use of such refrigerants. Since the cooling circuit and the external refrigeration circuit are separate from one another, there is the possibility of using flammable refrigerants in the external refrigeration circuit.

[0020] Preferably, the pump of the cooling circuit is configured as a circulation pump, in particular a speed-regulated circulation pump. Speed-regulated pumps can be operated particularly energy-efficiently. The pump can be configured, for example, as a brine pump, a glycol pump or a water pump.

[0021] A preferred embodiment of the application provides that a pressure relief valve, a vent valve and / or a membrane expansion vessel or a gas superposition cooling circuit is arranged in the cooling circuit. With the membrane expansion vessel or the gas superposition cooling circuit, the volume expansion of the refrigerant carrier can be taken into account, wherein there is no need to vent the refrigerant carrier. The pressure relief valve can act as a safety valve to vent the refrigerant to reduce the pressure when a maximum value of the pressure is exceeded. Air or other gases can be vented by the vent valve.

[0022] The laboratory cabinet, air conditioning cabinet, refrigeration cabinet or environmental simulation cabinet with a sample chamber according to the application has a temperature control device according to the application, wherein the consumer heat exchanger is arranged such that it temperature controls the sample chamber. The advantages of such a laboratory cabinet, air conditioning cabinet, refrigeration cabinet or environmental simulation cabinet correspond to the advantages described on the basis of the temperature control device.

[0023] It is a preferred refinement of the application that the external refrigeration circuit, preferably including the second heat exchanger, is arranged in a machine room separate from the sample chamber, which machine room in particular has a ventilation opening. In particular, with such a separation between the external refrigeration circuit and the cooling circuit it is possible to use a flammable refrigerant in the external refrigeration circuit, since the external refrigeration circuit is arranged in a machine room separate from the sample chamber, which machine room can be well ventilated, so that the safety requirements for a refrigeration circuit with a flammable refrigerant can be met there, which is not possible in an enclosed sample chamber in which there are possible ignition sources. The energy input from the sample chamber to the consumer heat exchanger for cooling the sample chamber can be carried out by means of the cooling circuit, wherein the second heat exchanger is arranged outside the sample chamber in the machine room.

[0024] In an advantageous refinement, the sample chamber is delimited by an inner wall, which is at least section-wise surrounded by an outer wall, wherein an insulation is at least section-wise arranged on the outside of the outer wall and the insulation is surrounded by a housing, wherein the consumer heat exchanger is arranged between the inner wall and the outer wall. This arrangement enables a particularly efficient energy input from the sample chamber into the consumer heat exchanger.

[0025] A particularly preferred design of the application provides that the evaporator is arranged between the outer wall and the insulation. This arrangement enables a particularly efficient dehumidification of the sample chamber of a laboratory cabinet, air conditioning cabinet, refrigeration cabinet or environmental simulation cabinet. BRIEF DESCRIPTION OF DRAWINGS

[0026] The application is explained in detail below on the basis of embodiments. In the drawings:

[0027] Figure 1 A schematic diagram of a first embodiment of a tempering device according to the application is shown, which has a cooling circuit with a refrigeration source, a consumer heat exchanger and a pump and an external refrigeration circuit with a compressor, a condenser and a first adjustable throttling member, wherein the cooling circuit and the external refrigeration circuit are coupled to one another by means of a second heat exchanger;

[0028] Figure 2 A schematic diagram of a second embodiment of a tempering device according to the application is shown, which corresponds to Figure 1 the tempering device shown and also has a third throttling member for returning injection into the compressor;

[0029] Figure 3 A schematic diagram of a third embodiment of a tempering device according to the application is shown, which corresponds to Figure 2 the tempering device shown and also has a second throttling member and an evaporator in parallel to the first throttling member and the second heat exchanger;

[0030] Figure 4 schematic diagram of a laboratory cabinet, air-conditioning cabinet, refrigeration cabinet or environmental simulation cabinet with a tempering device according to Figure 1 schematic diagram of a laboratory cabinet, air-conditioning cabinet, refrigeration cabinet or environmental simulation cabinet with a tempering device according to

[0031] Figure 5 schematic diagram of a laboratory cabinet, air-conditioning cabinet, refrigeration cabinet or environmental simulation cabinet with a tempering device according to Figure 4 schematic diagram of a laboratory cabinet, air-conditioning cabinet, refrigeration cabinet or environmental simulation cabinet with a tempering device according to DETAILED DESCRIPTION

[0032] Figures 1 to 3 different embodiments of a tempering device 10-1, 10-2, 10-3 are shown, Figure 4 and Figure 5 the installation of such a tempering device is shown. Identical reference signs denote identical or functionally identical parts, wherein, for a better overview, not all reference signs are given in all figures.

[0033] Figure 1 a schematic diagram of a first embodiment of a tempering device 10-1 is shown, which has a cooling circuit 20, shown for illustration purposes with dashed lines, in which a refrigeration carrier is arranged. By refrigeration carrier is meant a fluid which can be circulated through the cooling circuit. The refrigeration carrier can be a non-flammable fluid, for example a water-glycol mixture, a silicone oil or a salt solution.

[0034] The cooling circuit 20 has a refrigeration source 22 with a flow-in 22a and a flow-out 22b, a consumer heat exchanger 24 with a flow-in 24a and a flow-out 24b, which is arranged in the flow-out 22b of the refrigeration source 22, and a pump 26, which is located in the flow-out 24b of the consumer heat exchanger 24 and in the flow-in 22a of the refrigeration source 22. The circulation pump 26 can also be arranged alternatively in the flow-in 24a of the consumer heat exchanger 24. The pump 26 of the cooling circuit 20 can be designed as a circulation pump, in particular a speed-regulated circulation pump. Control takes place by means of a control unit, not shown. The consumer heat exchanger 24 can be designed as a finned heat exchanger, a plate heat exchanger or a microchannel heat exchanger. Depending on the design variant, the consumer heat exchanger 24 can be arranged, for example in the case of a finned heat exchanger or a microchannel heat exchanger, inclined to the vertical (cf. Fig. 1), or for example in the case of a plate heat exchanger, parallel to the vertical (cf. Fig. 2). Figure 4 Figure 5

[0035] In the cooling circuit 20, for example in the flow-out 26b of the pump 26, a temperature sensor 28 can be arranged.

[0036] ​​A pressure excess valve and / or a vent valve can also be arranged in the cooling circuit 20. Furthermore, the cooling circuit 20 can have a membrane expansion vessel 29 or a gas superimposed cooling circuit.

[0037] The refrigerant source 22 is part of a second heat exchanger 50, through which the external refrigeration circuit 60 is coupled to the cooling circuit 20. For the sake of illustration, the refrigeration circuit 60 is shown in solid lines so that it can be better distinguished from the cooling circuit 20. A refrigerant is arranged in the refrigeration circuit 60. By refrigerant is meant a fluid that can be circulated through the refrigeration circuit. Here, the refrigeration circuit 60 and the cooling circuit 20 are separated in terms of fluid technology. Only through the second heat exchanger 50 can thermal energy be transferred from the refrigerant carrier of the cooling circuit 20 to the refrigerant of the refrigeration circuit 60. The refrigerant can be a flammable fluid, for example a hydrocarbon, in particular propane or isobutane, or CO2.

[0038] The external refrigeration circuit 60 has a compressor 62 with a feed flow 62a and a return flow 62b, a condenser 64 with a feed flow 64a and a return flow 64b, and a first throttling member 66. Furthermore, the refrigeration circuit 60 has a refrigerant source 68 with a feed flow 68a and a return flow 68b, which is part of the second heat exchanger 50 and through which thermal energy can be transferred from the refrigerant source 22 of the cooling circuit 20.

[0039] In the embodiment shown, the heat exchanger 50 is designed as a counterflow heat exchanger. However, in principle, the heat exchanger 50 can also be operated in a co-flow. The second heat exchanger 50 can be designed as a plate heat exchanger or as a coaxial tube heat exchanger.

[0040] The compressor 62 is arranged in particular in the return flow of the second heat exchanger 50, in particular in the return flow 68b of the refrigerant source 68 of the refrigeration circuit 60, and the first throttling member 66 is arranged in the feed flow of the second heat exchanger 50, in particular in the feed flow 68a of the refrigerant source 68 of the refrigeration circuit 60. The condenser 64 is arranged in the return flow 62b of the compressor and in the feed flow 66a of the first throttling member 66.

[0041] The first throttling member 66 can be designed as a solenoid valve, in particular with a capillary, or as a continuous valve. The control or regulation is carried out by means of a control or regulation device, not shown.

[0042] Figure 2A schematic diagram of a second embodiment of the temperature control device 10-2 is shown. The main difference between this second embodiment and the first embodiment of the temperature control device 10-1 is that a third throttling member 92 may be provided, by means of which refrigerant can be returned to the compressor 62. The third throttling member 92 is arranged in parallel with the first throttling member 66 and the second heat exchanger 50. In other words, in this embodiment, the parallel line in which the third throttling member 92 is arranged runs from the return branch of the condenser 64 of the refrigeration circuit 60 to the inlet flow 62a of the compressor 62.

[0043] The third throttling member 92 can be configured as a solenoid valve, especially a solenoid valve with a capillary tube, or as a continuous valve. Control or regulation is performed by a control or regulation device not shown, wherein such control or regulation can be performed particularly independently of the control or regulation of the first throttling member 66.

[0044] Figure 3 A schematic diagram of a third embodiment of the temperature control device 10-3 is shown. The main difference between this third embodiment and the second embodiment of the temperature control device 10-2 is that the second throttling member 82 and the evaporator 84 can be arranged in parallel with the first throttling member 66 and the second heat exchanger 50. In other words, in this embodiment, the parallel pipeline in which the second throttling member 82 and the evaporator 84 are arranged runs from the return branch of the condenser 64 of the refrigeration circuit 60 to the starting flow 62a of the compressor 62. It should be noted here that the second throttling member 82 and the evaporator 84 can also be applied in principle to the first embodiment of the temperature control device 10-1 and are therefore independent of the presence of the third throttling member 92.

[0045] The second throttling member 82 can be configured as a solenoid valve, especially a solenoid valve with a capillary tube, or as a continuous valve. Control or regulation is performed by a control or regulation device not shown, wherein the control or regulation can be performed particularly independently of the control or regulation of the first throttling member 66, and if a third throttling member 92 is present, it can be performed independently of the control or regulation of the third throttling member 92.

[0046] Evaporator 84 can be configured as a blown evaporator.

[0047] Figure 4 It shows a sample chamber 110 and based on Figure 1 A schematic diagram of the temperature control device 10-1, including its use as a laboratory cabinet, air conditioning cabinet, refrigeration cabinet, or environmental simulation cabinet, is provided. The heat exchanger 24 is arranged such that it regulates the temperature of the sample chamber 110. In principle, it is conceivable to use a device based on... Figures 1 to 3All of the temperature control devices 10-1 to 10-3 are installed in a laboratory cabinet, air-conditioning cabinet, refrigeration cabinet or environmental simulation cabinet 100.

[0048] The laboratory cabinet, air-conditioning cabinet, refrigeration cabinet or environmental simulation cabinet 100 has a machine room 120 separate from the sample room 110, in which the external refrigeration circuit 60, preferably including the second heat exchanger 50, is arranged in the machine room 120. The machine room 120 has, inter alia, a ventilation opening and can thereby meet the safety requirements for the use of flammable refrigerants, in particular hydrocarbons, such as propane or isobutane. Advantageously, only the consumer heat exchanger 24 of the temperature control device 10-1 is arranged in or at the sample room 110, while the further components of the temperature control device 10-1 are arranged in a spatially separated manner in the machine room 120.

[0049] The sample room 110 can be delimited by an inner wall 112 which is at least sectionally surrounded by an outer wall 114, wherein an insulation 116 is arranged at least sectionally on the outside of the outer wall 114 and is surrounded by a housing 130. The consumer heat exchanger 24 is advantageously arranged between the inner wall 112 and the outer wall 114, so that a good temperature input from the sample room 110 can be achieved.

[0050] Figure 5 A laboratory cabinet, air-conditioning cabinet, refrigeration cabinet or environmental simulation cabinet according to Figure 4 is shown, wherein in the temperature control device 10-1 an evaporator 84 based on Figure 3 is additionally arranged. Here, the evaporator 84 is arranged in particular between the outer wall 114 and the insulation 116, so that dehumidification can be achieved.

[0051] Legend of the figures:

[0052] 10-1 to 10-3 Temperature control device

[0053] 20 Cooling circuit

[0054] 22 Refrigeration source

[0055] 22a Feed flow

[0056] 22b Return flow

[0057] 24 Consumer heat exchanger

[0058] 24a Feed flow

[0059] 24b Return flow

[0060] 26 Pump

[0061] 26a Feed flow

[0062] 26b Return flow

[0063] 28 temperature sensor

[0064] 29 film expansion vessel

[0065] 50 second heat exchanger

[0066] 60 external refrigeration circuit

[0067] 62 compressor

[0068] 62a feed flow

[0069] 62b return flow

[0070] 64 condenser

[0071] 64a feed flow

[0072] 64b return flow

[0073] 66 first throttling member

[0074] 68 refrigeration source

[0075] 68a feed flow

[0076] 68b return flow

[0077] 82 second throttling member

[0078] 84 evaporator

[0079] 92 third throttling member

[0080] 100 laboratory cabinet, air conditioning cabinet, refrigeration cabinet or environmental simulation cabinet

[0081] 110 sample chamber

[0082] 112 inner wall

[0083] 114 outer wall

[0084] 116 insulation

[0085] 120 machine chamber

[0086] 130 housing

Claims

1. A temperature regulating device (10-1, 10-2, 10-3) having a cooling circuit (20) having a cooling medium, wherein, The cooling circuit (20) has a refrigeration source (22), a heat exchanger (24) for consumable devices located in the return flow (22b) of the refrigeration source (22), and a pump (26), wherein the refrigeration source (22) is part of a second heat exchanger (50), and an external refrigeration circuit (60) is coupled to the cooling circuit (20) via the second heat exchanger (50) with refrigerant. The external refrigeration circuit (60) is characterized in that it has a compressor (62), a condenser (64), and a first throttling member (66).

2. The seat device (12a) according to claim 1, characterized in that, The compressor (62) is arranged in the reflux of the second heat exchanger (50), and the first throttling member (66) is arranged in the inflow of the second heat exchanger (50).

3. The temperature control device according to any one of the preceding claims, characterized in that, The compressor (62) is configured as a variable frequency compressor.

4. The temperature control device according to any one of the preceding claims, characterized in that, The first throttling member (66) is configured as a solenoid valve, especially a solenoid valve with a capillary tube.

5. The temperature control device according to any one of the preceding claims, characterized in that, The second throttling component (82) and the evaporator (84) are arranged in parallel with the first throttling component (66) and the second heat exchanger (50).

6. The temperature regulating device according to claim 5, characterized in that, The evaporator (84) is configured as a blown evaporator.

7. The temperature regulating device according to claim 5 or 6, characterized in that, The second throttling member (82) is configured as a solenoid valve, especially a solenoid valve with a capillary tube.

8. The temperature control device according to any one of the preceding claims, characterized in that, Refrigerant is returned to the compressor (62) via a third throttling member (92), which is arranged in parallel with the first throttling member (66) and the second heat exchanger (50).

9. The temperature regulating device according to claim 8, characterized in that, The third throttling component (92) is configured as a solenoid valve, especially a solenoid valve with a capillary tube.

10. The temperature control device according to any one of the preceding claims, characterized in that, The second heat exchanger (50) is configured as a plate heat exchanger or a coaxial tube heat exchanger.

11. The temperature regulating device according to any one of the preceding claims, characterized in that, The cooling circuit (20) has a non-flammable fluid, such as a water-glycol mixture, silicone oil or salt solution, as the refrigeration carrier.

12. The temperature control device according to any one of the preceding claims, characterized in that, The external refrigeration circuit (60) has hydrocarbons, especially propane or isobutane, as refrigerants.

13. The temperature control device according to any one of the preceding claims, characterized in that, The pump (26) of the cooling circuit is configured as a circulating pump, especially a speed-regulating circulating pump.

14. The temperature regulating device according to any one of the preceding claims, characterized in that, An overpressure valve is arranged in the cooling circuit (20).

15. The temperature regulating device according to any one of the preceding claims, characterized in that, An exhaust valve is arranged in the cooling circuit (20).

16. The temperature control device according to any one of the preceding claims, characterized in that, A membrane expansion vessel (29) or a gas superposition cooling circuit is arranged in the cooling circuit (20).

17. A laboratory cabinet, air-conditioning cabinet, refrigeration cabinet, or environmental simulation cabinet (100), comprising a sample chamber (110) and a temperature control device (10-1, 10-2, 10-3) according to any one of the preceding claims, wherein, The heat exchanger (24) of the consumable device is arranged such that the heat exchanger (24) of the consumable device regulates the temperature of the sample chamber (110).

18. The laboratory cabinet, air conditioning cabinet, refrigeration cabinet, or environmental simulation cabinet (100) according to claim 17, characterized in that, The external cooling circuit (60), preferably including the second heat exchanger (50), is arranged in a machine room (120) separate from the sample chamber (110), the machine room (120) having ventilation openings in particular.

19. The laboratory cabinet, air conditioning cabinet, refrigeration cabinet, or environmental simulation cabinet (100) according to claim 17 or 18, characterized in that, The sample chamber (110) is defined by an inner wall (112), which is at least segmentally surrounded by an outer wall (114), wherein an insulating portion (116) is arranged at least segmentally on the outer side of the outer wall (114), and the insulating portion (116) is surrounded by a housing (130), wherein the heat exchanger (24) of the consumable device is arranged between the inner wall (112) and the outer wall (114).

20. The laboratory cabinet, air conditioning cabinet, refrigeration cabinet, or environmental simulation cabinet (100) according to claim 19, characterized in that, The evaporator (84) is arranged between the outer wall (114) and the insulation part (116).

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