DE102019216649A1 - Refrigerator with several temperature zones - Google Patents

Abstract

A refrigeration device has at least one storage chamber (3) and an evaporator (6) extending on a wall of the storage chamber (3). The evaporator (6) has a first injection port (14) and a suction port (17) and a second injection port (15), which the evaporator (6) in a downstream section (19), which from the first or the second injection port (14, 15) is traversed by injected refrigerant, and divides an upstream section (18) through which only refrigerant injected via the first injection port (14) flows. A compressor (9) for circulating the refrigerant can be operated in order to drive a refrigerant flow via the second injection connection (15) when the compressor (9) is running.

Description

The present invention relates to a refrigeration device, in particular a household refrigeration device, in which several temperature zones can be implemented.

The temperature zones of such a refrigeration device are conventionally implemented as individual storage chambers which are separated from one another by a wall filled with thermal insulation material. The wall is a fixed, non-removable part of the housing of the refrigerator.

Out WO 2007/074094 A1 a refrigeration device is known in which an evaporator has a second injection port between a first injection port and a suction port. This second injection port is provided in order to use it to reduce the overpressure in the condenser at the time the compressor is switched off and to prevent that, while the pressure in the condenser is reduced after the compressor is switched off, only slightly expanded and accordingly warm refrigerant penetrates from the condenser into the evaporator and displaces the existing cold refrigerant to a large extent.

One object of the present invention is to create a refrigeration device that can be used in a versatile and flexible manner.

The object is achieved in that, in a refrigeration device with a storage chamber and at least one evaporator which extends on a wall of the storage chamber and has a first injection port and a suction port, a second injection port that connects the evaporator into a downstream section that extends from above the first or the second injection port is traversed by injected refrigerant, and divides an upstream section, which is traversed only by refrigerant injected via the first injection port, and a compressor for circulating the refrigerant, the compressor can be operated to drive a refrigerant flow via the second injection port when the compressor is running .

It is thus possible to continuously apply refrigerant to the downstream section of the evaporator, while the upstream section is empty. This results in a lower temperature in a region of the storage chamber that is cooled by this downstream section than in a region that is cooled by the upstream section. If the refrigerant is distributed to the two injection points in a controlled ratio, two temperature zones with an adjustable temperature difference between the two can be implemented in the storage chamber.

In order to enable a versatile use for refrigerated goods in different sizes, the storage chamber should be free of internals containing jacketed insulating material and in particular of permanently installed partition walls.

A removable shelf can, however, be arranged at the level of a boundary between the upstream section and the downstream section in the storage chamber in order to restrict the exchange of air between the different areas of the storage chamber and thus to favor a temperature difference between the two, or at least around the boundary between the different ones To mark temperature zones of the storage chamber so that they are visible to the user.

This limit can also be identified by different interior fittings of the storage chamber on both sides. In particular, one or more pull-out boxes can be provided in the storage chamber on only one side of a boundary between the upstream section and the downstream section. The one or more pull-out drawers are preferably located on the side of the downstream section in order to be able to use the area cooled by this similar to a cold storage compartment, while temperatures typical for a normal refrigeration compartment can prevail in the area cooled by the upstream section.

The evaporator preferably has a refrigerant line extending from the first injection port to the suction port, and the second injection port is formed at an intermediate point of the refrigerant line, so that refrigerant supplied via the first injection port and the second injection port pass through the same downstream section of the refrigerant line. However, it would also be conceivable to provide two refrigerant lines on the evaporator, one of which leads from the first injection connection to the suction connection and the other leads from the second injection connection to the suction connection and which meet at the suction connection.

In a first design, the refrigerant line can extend in one piece over the second injection connection, and the second injection connection can be formed by a capillary which crosses a puncture in the wall of the refrigerant line.

Alternatively, the refrigerant conduit may comprise two telescopically interlocking parts, an upstream and a downstream part, and the second injection port may be formed by a capillary extending between the interlocking parts.

Upstream of the second injection port, the refrigerant line can have a check valve in order to prevent refrigerant fed in via the second injection port from flowing back into the upstream section of the evaporator. The check valve can be superfluous if the backflow of the refrigerant into the upstream section can be prevented by arranging the upstream section above the downstream section.

Arranging the upstream section of the evaporator above the downstream section is also useful in order to maintain a high temperature difference between the areas of the storage chamber cooled by these sections, since the air cooled at the evaporator tends to collect near the bottom of the storage chamber anyway.

Conversely, a fan can be provided in the storage chamber in order, if such a temperature difference is not desired, to drive an exchange of air between the lower and upper areas of the storage chamber.

A user interface can be set up to enable a user to choose between an operating mode in which only the first injection port is acted upon with refrigerant, and an operating mode in which the second injection port is also acted upon with refrigerant at least temporarily. If the above-mentioned fan is present, its operation can be restricted to the former operating mode in order to minimize the temperature gradient between the bottom and top of the storage chamber in this mode.

According to a preferred embodiment, a central evaporator section, through which refrigerant flows on the way from the upstream section to the downstream section, is arranged below the downstream section.

If the downstream section is not the lowermost section of the evaporator, this facilitates the implementation of an internal heat exchanger of sufficient length in which the capillaries running to the injection connections are each in close thermal contact with a suction line emanating from the suction connection.

A refrigerant line of the evaporator can have a rising section upstream of the second injection port in order to be able to retain liquid refrigerant in the upstream section during the injection via the second injection port and thus to be able to maintain its cooling effect.

The compressor can be operated intermittently in a manner known per se, i.e. switched on when there is a demand for refrigeration in the storage chamber and switched off when the demand for refrigeration is satisfied. In order to avoid displacement of liquid refrigerant from the evaporator, an operating phase of the compressor preferably comprises exactly one injection phase via the second injection port and one injection phase via the first injection port.

The operating phase can begin with injection via the second injection port, but then you should switch to injection via the first injection port in good time, even before the cooling requirement of the part of the storage chamber cooled by the downstream section of the evaporator is covered, since the downstream section of the evaporator is then covered is further cooled by cold vapor or overflowing liquid refrigerant from the upstream section. If, on the other hand, the phase of injection via the second injection port follows the injection via the first injection port, a switch can be made at the moment in which the cooling requirement in the part of the storage chamber cooled by the upstream section is covered, since this part is injected via the second injection port Refrigerant is no longer being cooled. The control of the compressor operation is therefore simpler in the latter case.

In addition, the above-mentioned rising section of the refrigerant line can ensure that, at the time of switching, liquid refrigerant is retained in the upstream section and continues to develop a cooling effect there even after the refrigerant supply has ended. At the same time, the rising section can prevent liquid refrigerant injected via the first injection port from reaching the downstream section of the evaporator in large quantities and being displaced therefrom by refrigerant later injected via the second injection port.

• 1 eine schematische Ansicht eines Kältegeräts gemäß einer ersten Ausgestaltung der Erfindung;
• 2 eine schematische Ansicht gemäß einer zweiten Ausgestaltung;
• 3 einen schematischen Schnitt durch das Kältegerät gemäß der zweiten Ausgestaltung;
• 4 eine schematische Ansicht gemäß einer dritten Ausgestaltung;
• 5 einen zweiten Einspritzanschluss gemäß einer ersten Ausgestaltung; und
• 6 den zweiten Einspritzanschluss gemäß einer zweiten Ausgestaltung.

Further features and advantages of the invention emerge from the following description of exemplary embodiments with reference to the accompanying figures. Show it:

• 1 a schematic view of a refrigerator according to a first embodiment of the invention;
• 2 a schematic view according to a second embodiment;
• 3 a schematic section through the refrigeration device according to the second embodiment;
• 4th a schematic view according to a third embodiment;
• 5 a second injection port according to a first embodiment; and
• 6th the second injection port according to a second embodiment.

1 shows a schematic front view of a refrigeration device according to a first embodiment of the invention. Only one inner container is of a conventionally constructed heat-insulating body 1 a storage room 3 and one the inner container 1 surrounding thermal insulation layer 5 indicated.

Between a rear wall of the inner container 1 and the thermal insulation layer extending behind it 5 is a plate-shaped evaporator 6th , for example of the ToS or Rollbond type, embedded.

In an engine room 4th below the inner container 1 and beyond the thermal insulation layer 5 is a compressor 9 housed. One from the compressor 9 outgoing refrigerant line runs through a condenser 10 to a directional control valve 11 . From the directional control valve 11 outgoing capillaries 12th , 13th extend to a first injection port 14th and a second injection port 15th of the evaporator 6th .

A refrigerant pipe 16 of the evaporator 6th runs in meanders from the first injection port 14th via the second injection port 15th to a suction connection 17th .

The second injection port 15th divides the evaporator 6th into two sections, one upstream in relation to the direction of circulation of the refrigerant 18th and a downstream section 19th . Each of these sections occupies at least a quarter, preferably at least 40%, of the area of the evaporator 6th a.

In the embodiment shown here, the refrigerant line runs from the suction connection 17th directly back to the compressor 9 . Alternatively, the suction connection 17th Via one or more evaporators from other storage chambers with the compressor 9 be connected. One from the last evaporator in the refrigerant circuit back to the compressor 9 leading suction pipe 27 can be in close thermal contact with the capillaries over part of its length 12th , 13th or a line section 28 upstream of the directional control valve 11 be led to an internal heat exchanger 29 to build.

A control circuit 20th is with a temperature sensor 21 at the storage room 3 connected to the compressor 9 based on the temperatures measured there. In the simplest case, the control consists of the compressor 9 to be switched on if a target temperature is exceeded by more than an allowable amount and to be switched off when the desired temperature is undercut by more than an allowable amount.

A user interface 22nd with controls of any known type is provided to enable a user to set the target temperature. A control element of the interface 22nd is provided to enable the user to choose between an operating mode with homogeneous temperature distribution in the storage chamber 3 and to enable an operating mode with inhomogeneous temperature distribution.

The control circuit holds in the operating mode with homogeneous temperature distribution 20th the directional control valve 11 at least during the operating phases of the compressor 9 in a position in which there is the condenser 10 with the first injection port 14th connects. The refrigerant injected there runs through the refrigerant pipe 16 along its entire length and thus ensures even cooling of the entire evaporator 6th .

There on the evaporator 6th cooled air in the storage chamber 3 drops, this is also in its lower area, below a lower edge of the evaporator 6th , cooled, and it results in a substantially over the entire height of the storage chamber 3 even cooling.

About a temperature difference between the ceiling and floor of the storage chamber 3 To be able to reduce even further in the operating mode with homogeneous temperature distribution, in the storage chamber 3 a fan 23 be provided, the air circulation in the storage chamber 3 drives and that of the control circuit 20th at the same time as the compressor 9 or is switched on and off with a slight time delay.

In the operating mode with inhomogeneous temperature distribution, each operating phase of the compressor changes 9 a period of time in which the directional control valve 11 Refrigerant to the first injection port 14th and a period of time in which it takes the refrigerant to the second injection port 15th directs. The durations of these periods of time or their relationship to one another can be fixed; but it can also be given to the user at the user interface 22nd a desired temperature difference or two different target temperatures for one of the upstream section 18th refrigerated area 24 and one from the downstream section 19th refrigerated area 25th the storage room 3 to choose, whereupon the Control circuit 20th makes a suitable definition of the time periods in accordance with this selection.

This selection can be made on the basis of a prototype of the refrigeration device and stored in a memory of the control circuit 20th stored data are taken. But it is also conceivable in each of the areas 24 , 25th Provide a temperature sensor in each case and select the durations of the time spans so that in both areas 24 , 25th a preselected target temperature is maintained.

2 shows a second embodiment of the evaporator 6th . The upstream section 18th and the downstream section 19th each have separate base plates on which the refrigerant pipe 16 runs. So is the heat flow between the sections 18th , 19th of the evaporator 6th largely suppressed, so that in the operating mode with inhomogeneous temperature distribution there is a greater difference between the temperatures of the sections 18th , 19th and consequently also the areas 24 , 25th the storage room 3 is attainable.

The division of the base plate into two also favor a temperature difference between the sections 18th , 19th in the operating mode with homogeneous temperature distribution, but here, if necessary, a temperature stratification in the storage chamber can be counteracted with the aid of a fan as described above.

An internal heat exchanger 29 The compressed refrigerant before it reaches the injection ports 14th , 15th pre-cooled, is through the suction pipe 27 and parts of the capillaries 12, 13 are formed. A second internal heat exchanger 30th can through one of the sections 18th , 19th of the evaporator 6th connecting section 31 of the refrigerant pipe 16 and from the directional control valve (not shown) 11 to the first injection port 14th running capillary 12th be educated.

The heat exchanger 30th Providing is particularly useful when the refrigerant pipe 16 as in 2 shown just before exiting the upstream section 18th of the evaporator 6th an ascending pipe section 32 has and therefore the connecting pipe section 31 along the length of the upstream section 18th extends downwards.

Such a course of the refrigerant pipe 16 is particularly useful when in the operating mode with inhomogeneous temperature distribution during an operating phase of the compressor 9 the time span of the application of the second injection port 15th with refrigerant to the period of exposure to the first injection port 14th follows: Since while the first injection port is being admitted 14th liquid refrigerant only then the downstream section 19th of the evaporator 6th reached when the refrigerant pipe 16 in the upstream section 18th is full, the downstream section contains mostly or exclusively steam at the time of switching, and by filling the downstream section 19th with liquid refrigerant via the injection port 15th can reduce the cooling capacity of the downstream section 19th can be increased significantly; at the same time, the cooling effect of the upstream section remains 18th fully preserved by the liquid refrigerant stored in it.

3 shows a schematic section through the body of a refrigeration device with the evaporator 6th out 2 . The sections 18th , 19th are located one above the other on the rear wall of a single inner container 1 limited storage room 3 . A shelf 33 equal to a gap between the sections 18th , 19th divides the storage room 3 into that of the upstream section 18th refrigerated area 24 and the area cooled by the downstream portion 25th . When the shelf 33 is free of openings, for example is largely formed by a glass plate, it effectively prevents an exchange of air between the areas 24 , 25th and thus favors a significant temperature difference between them.

Also one in the field 25th arranged pull-out box 26th can help limit air exchange.

So it is possible to the area 24 to operate in a temperature range typical for a normal refrigerator compartment and in the range 25th To reach temperatures of a cold storage compartment.

A fan in the area 24 In this case, the temperature cannot be equalized by air exchange between the areas 24 and 25th bring about more, but it can counteract a temperature stratification that would otherwise be in the area 24 would result in that this would be at its lower edge through the shelf 33 heat through to the area 25th gives.

4th shows an embodiment with a three-part evaporator 6th . The upstream section 18th of the evaporator 6th resembles that in 3 and is therefore not described again here. The one from this section 18th outgoing connecting pipe section 31 however, does not lead to the downstream section 19th but to an intermediate section 34 that is under the downstream section 19th is arranged. In one (in the 4th not shown) from the evaporator 6th cooled, contiguous storage chamber three areas with different temperatures can be realized, a cold one in the middle, at the level of the Section 19th , and two warm above and below, each at the level of the sections 18th and 34 .

To allow liquid refrigerant to flow back from the second injection port in the operating mode with inhomogeneous temperature distribution 15th upstream to the lower intermediate section 34 can prevent a check valve 42 in one of the intermediate section 34 to the downstream section 19th rising part of the refrigerant pipe 16 be provided

Here, too, the cold area can be separated from the warm area through shelves or possibly a pull-out box 26th be demarcated.

5 shows an embodiment of the second injection port 15th in a longitudinal section along a plane passing through the longitudinal directions of the refrigerant pipe 16 and the capillary 13th is defined. The refrigerant pipe 16 extends in one piece over the injection port 15th away. One end of the capillary 13th is about a puncture 35 in the wall 36 of the refrigerant pipe 16 inserted into the latter, preferably in the direction of flow of the refrigerant in the refrigerant pipe (indicated by an arrow in the figure) 16 . The puncture 35 is sealed by solder. To prevent the seal from leaking, especially when installing the evaporator 6th A section can prevent this in a refrigeration device 37 the capillary 13th outside the refrigerant pipe 16 on the base plate of the evaporator 6th be soldered or fixed in some other suitable manner; it is also conceivable to use a section of the capillary 13th , for example by wrapping an adhesive tape around one of them for a puncture 35 to fasten adjacent section of the refrigerant pipe in a fitting manner.

An injection port from the in 5 The type shown can also be easily implemented on a Rollbond evaporator.

6th shows an alternative embodiment of the injection port 15th . The refrigerant pipe 16 is divided into two parts here in an upstream part 38 and a downstream part 39 . On the upstream part 38 is a gutter 40 recessed that is sized to the capillary 13th to record. The downstream part 39 shows a widening at its end 41 on, in which the end of the upstream part 38 including the one in the gutter 40 inserted capillary 13th is retractable. When pushed in, the parts 38 , 39 and the capillary 13th soldered together tightly.

List of reference symbols

1

Inner container

2

-

3

Storage room

4th

Engine room

5

Thermal insulation layer

6th

Evaporator

7th

-

8th

-

9

compressor

10

Condenser

11

Directional control valve

12th

capillary

13th

capillary

14th

Injection port

15th

Injection port

16

Refrigerant pipe

17th

Suction connection

18th

upstream section

19th

downstream section

20th

Control circuit

21

Temperature sensor

22nd

User interface

23

Fan

24

(from the upstream section) cooled area

25th

(from the downstream section) cooled area

26th

Pull-out box

27

Suction pipe

28

Line section

29

internal heat exchanger

30th

second internal heat exchanger

31

connecting section

32

rising pipe section

33

Fold bottom

34

intermediate section

35

Puncture

36

wall

37

Section (of the capillary 13th )

38

upstream part (of the refrigerant pipe 16 )

39

downstream part (of the refrigerant pipe 16 )

40

Gutter

41

Expansion

42

check valve

QUOTES INCLUDED IN THE DESCRIPTION

This list of the documents listed by the applicant was generated automatically and is included solely for the better information of the reader. The list is not part of the German patent or utility model application. The DPMA assumes no liability for any errors or omissions.

Patent literature cited

• WO 2007/074094 A1 [0003]

Claims (15)

Refrigeration device with at least one storage chamber (3) and an evaporator (6) which extends on a wall of the storage chamber (3) and which has a first injection port (14) and a suction port (17), a second injection port (15) which connects the evaporator (6) divides into a downstream section (19) through which refrigerant injected via the first or the second injection port (14, 15) flows, and an upstream section (18) which is only injected via the first injection port (14) Refrigerant is flowed through, and a compressor (9) for circulating the refrigerant, characterized in that the compressor (9) can be operated to drive a refrigerant flow via the second injection port (15) when the compressor (9) is running. Appliance after Claim 1 , characterized in that the storage chamber (3) is free of internals containing jacketed insulating material. Appliance after Claim 1 or 2 , characterized in that a shelf (33) is removably disposed in the storage chamber (3) at the level of a boundary between the upstream section (18) and the downstream section (19). Refrigerating device according to one of the preceding claims, characterized in that one or more pull-out boxes (26) are provided in the storage chamber (3) on only one side of a boundary between the upstream section (18) and the downstream section (19). Refrigerating device according to claim 1, characterized in that the evaporator (6) has a refrigerant line (16) extending from the first injection connection (14) to the suction connection (17) and the second injection connection (15) at an intermediate point of the refrigerant line ( 16) is formed. Appliance after Claim 5 , characterized in that the refrigerant line (16) extends in one piece over the second injection port (15) and that the second injection port (15) is formed by a capillary (13) which has a perforation (35) in the wall (36) the refrigerant line (16) crosses. Appliance after Claim 5 , characterized in that the refrigerant line (16) comprises two telescopically interlocking parts (38, 39) and that the second injection port (15) is formed by a capillary (13) which extends between the interlocking parts (38, 39). Refrigeration device according to one of the Claims 5 to 6th , characterized in that the refrigerant line (16) has a check valve (42) upstream of the second injection port (15). Refrigerating appliance according to one of the preceding claims, characterized in that the downstream section (19) of the evaporator is lower than the upstream section (18). Refrigerating device according to one of the preceding claims, characterized in that at least one fan (23) is provided in the storage chamber (3). Refrigeration device according to one of the preceding claims, characterized in that a user interface (22) is set up to enable a selection between an operating mode in which only the first injection port (14) is supplied with refrigerant, and an operating mode in which at least temporarily the second injection port (15) is acted upon with refrigerant to enable. Refrigerating device according to one of the preceding claims, characterized in that a central evaporator section (34) through which refrigerant flows on the way from the upstream section (18) to the downstream section (19) is arranged below the downstream section (19). Refrigerating device according to one of the preceding claims, characterized in that a refrigerant line (16) of the evaporator (6) has a rising section (32) upstream of the second injection connection (15). Method for operating a refrigeration device according to one of the preceding claims, in which the compressor (9) is operated intermittently, characterized in that an operating phase of the compressor (9) is exactly one time span of the injection via the second injection connection (15) and one time span of the Injection via the first injection port (14). Procedure according to Claim 14 , characterized in that the phase of injection via the second injection connection (15) is followed by a phase of standstill of the compressor (9).

Images