EP2694887B1 - Domestic refrigerator having refrigerant pipelines - Google Patents

Description

The invention relates to a household refrigerating appliance, comprising at least one heat-insulating inner container with a coolable interior, and designed for cooling the interior refrigerant cycle system comprising at least a compressor, a condenser, and an evaporator, which are connected to form the refrigerant circuit system by refrigerant pipelines, of which at least two refrigerant pipes each have a feed pipe end portion and of which a further refrigerant pipe has a drain pipe end portion into which the two inlet pipe end portions open.

From the DE 197 56 861 A1 a refrigeration device with a refrigerant circuit system and a heat-insulating housing is known, within which at least two thermally separated cold compartments of different temperature are arranged, each of which is cooled by a corresponding cooling capacity evaporator, wherein serving to cool the compartments evaporators together in a refrigeration cycle arranged in series with one another and are supplied with refrigerant by a compressor located in the refrigeration circuit, wherein at least two injection points are provided on the evaporator to produce the lower temperature, each of which is preceded by a throttling device with a different flow resistance and each of which is controlled by a deflection ,

DE-A-10 2006 061 091 discloses a household refrigerator according to the preamble of claim 1.

The object of the invention is to provide a household refrigerator with an improved refrigerant cycle system.

The object is achieved by a household refrigerator, comprising at least one heat-insulating inner container with a coolable interior, and designed for cooling the interior refrigerant cycle system comprising at least a compressor, a condenser, and an evaporator, which are connected to form the refrigerant circuit system by refrigerant pipelines of which at least two refrigerant pipes each have a Zulaufrohrleitungsendabschnitt and of which a further refrigerant pipe has a drain pipe end portion into which the two Zulaufrohrleitungsendabschnitte open, in the at least one of the two inlet pipe end sections has a pipe section that widens in the flow cross-section.

A refrigerant cycle system generally includes at least one compressor, at least one condenser, and at least one evaporator. The refrigerant is first compressed by the compressor, which heats the refrigerant. The compressed, heated refrigerant is cooled in the condenser, wherein it can at least partially pass from a gaseous phase into a liquid phase. The liquefied, cooled refrigerant is then supplied to a throttle, which expands the liquefied, cooled refrigerant into an evaporator. By the compressed refrigerant is expanded, it cools down, whereby the evaporator and evaporator plates coupled to the evaporator plates, evaporator fins are strongly cooled. The evaporator or the evaporator plates or evaporator plates are coupled to at least one coolable interior, so that this interior is cooled. The interior forms a cold room and is used for example for frost-free cooling of refrigerated goods, preferably at temperatures between plus 4 and plus 8 degrees Celsius. However, the refrigerator can also be designed as a zero-degree compartment, in particular for keeping fresh fruits or vegetables. Alternatively, the interior may form a freezer compartment which generally serves to freeze frozen food at about minus 18 degrees Celsius. The household refrigerator may have at least one freezer compartment and at least one cold room.

The freezer compartment and the refrigerator can each be assigned its own evaporator. These at least two evaporators may constitute components of a single refrigerant cycle system, in particular a single compressor refrigerant cycle system. The components of the refrigerant cycle system, in particular compressors, evaporators, condenser and throttles and / or expansion valves are generally connected by refrigerant pipelines. Depending on how the components in the refrigerant cycle system are interconnected, one or more branches in the refrigerant cycle system may be necessary. A branch can also be designed as an inlet, in which, for example, two or more inlet pipe end sections open into a common outlet pipe end section. Such a pipe branch or pipe junction can be designed, for example, T-shaped or Y-shaped.

Occasionally there is the requirement that refrigerant is supplied via a capillary tube in a refrigerant pipe, in particular to be injected. Capillary tubes can form chokes in refrigerant cycle systems. Capillary tubes are known and commonly used in household refrigeration appliances. Capillary tubes are characterized by a reduced, in particular greatly reduced, flow cross-section compared to the other refrigerant pipelines.

If refrigerant from a particularly thin capillary tube is now introduced or injected into a refrigerant pipeline with in particular a significantly larger flow cross section, then the refrigerant expands into the refrigerant pipeline, which may lead to undesired frost spots or unwanted noise developments in the region of the point of introduction.

By having at least two refrigerant pipes, each having a Zulaufrohrleitungsendabschnitt and of which a further refrigerant pipe has a Ablaufrohrleitungsendabschnitt into which the two Zulaufrohrleitungsendabschnitte open, at least one of the two Zulaufrohrleitungsendabschnitte has a widening in flow cross-section pipe section, the refrigerant gradually relaxes along the pipe section, so that, for example, a high pressure of the refrigerant is reduced more slowly, or more gradually. By a gradual pressure reduction unwanted frost or unwanted noise developments can be completely avoided or at least reduced.

The inflow pipe end section may have a flow cross-sectional course which extends between the pipe section widening in the flow cross-section and an outlet-side front end of the inflow pipe end section or a pipe connection sleeve, a necking-free, in particular constant or even increasing flow profile. The feed pipe can, for example, have a flow cross-section or inside diameter that is constant over its longitudinal course. In the vicinity of the feed pipe end section, this constant flow cross section or inner diameter can expand to a larger flow cross section or inner diameter. In the simplest case, this extension can occur at a discrete point, so to speak, suddenly, or gradually over a distance.

In all embodiments, therefore, the pipe section widening in the flow cross-section can be continuous, in particular conically widening.

At the pipe section that widens in the flow cross section, a pipe section with a constriction-free, in particular constant or even increasing flow cross-sectional profile can follow, in particular before an exit-side front end of the inlet pipe end section is reached. At the constant small, in particular capillary flow cross-section can thus join a pipe section with a cross-sectional widening and the pipe section with a cross-sectional widening can then connect another pipe section with a particular constant enlarged flow cross-section before this pipe assembly opens into the discharge pipe end portion. The pipe section with a constant small, in particular capillary flow cross-section, the pipe section with the cross-sectional widening and the pipe section with the particularly constant enlarged flow cross section can be formed by forming on a one-piece inlet pipe end section, or be composed of individual separate pipe sections, for example by soldering. In such a pipe arrangement, however, flow cross-section reductions, in particular constrictions in the flow direction of the refrigerant, should at least substantially be avoided, if not completely excluded.

The pipe section widening in the flow cross-section can be made widening up to a constant outflow cross-section, in particular an outflow cross-section corresponding to the outflow cross-section of the other inlet pipe end section. For example, in the case of two feed pipe end sections, the two feed pipe end sections can have the same or at least approximately the same flow cross section at their respective front ends.

In all embodiments, the pipe section widening in the flow cross section can have a circular flow cross section. Alternatively or additionally, a hollow-cylindrical, in particular hollow circular-cylindrical end pipe section can adjoin the pipe section widening in the flow cross-section. All pipe sections can form at least approximately the same wall thickness both have a circular inner wall cross section and a circular outer wall cross-section.

The pipe section widening in the flow cross-section can be formed, for example, on a separate pipe connection sleeve, which is attached to the inlet pipe end section, in particular soldered. In other words, this may mean that an intermediate pipe piece is inserted between the actual feed pipe end portion and the drain pipe end portion. The intermediate pipe section may have the pipe section widening in the flow cross section and / or the hollow cylindrical, in particular hollow circular cylindrical end pipe section having a constant flow cross section.

In all embodiments, the pipe section widening in the flow cross-section can be aligned coaxially with the feed pipe end section. This means that at least substantially the same, in particular the greatest possible distance from the inner walls of the pipe section widening in the flow cross-section, refrigerant exits the front end of the particular capillary feed pipe end section.

The inlet pipe end section can be formed, for example, by a capillary, which is adjoined by the pipe section widening in the flow cross section, in particular to which capillary a tube section of a pipe connection sleeve can be connected, which has the pipe section widening in the flow cross section. The tube section can aufeisen a uniform inner diameter, which is substantially equal to or only slightly larger than the outer diameter of the capillary. Thus, an end portion of the capillary can be prefixed by simply inserting it into the tube section on the tube coupling sleeve. By such prefixing the capillary can be easily connected to the pipe connection sleeve, in particular soldered or glued. In particular, during installation, the depth can also be set by which the capillary should project into the pipe connection sleeve, in particular into the pipe section widening in the flow cross section.

The capillary can thus protrude within the pipe connection sleeve into the conically widening pipe section. In this embodiment, exit end face The capillary of the inner wall diameter so not continuously into the widening in the flow cross-section pipe section, but has a jump. Depending on how far extends the capillary within the pipe connection sleeve into the flared pipe section, different flow conditions can be adjusted. Thus, the flow conditions during assembly of household refrigerators can be optimally adjusted or adjusted.

In all embodiments, the two Zulaufrohrleitungsendabschnitte can be used parallel to each other in the drain pipe end portion. As a result, refrigerant enters the downcomer end portion from at least approximately the same direction. In addition, a flow deflection from the Zulaufrohrleitungsendabschnitten is reduced to the drain pipe end portion to a minimum.

The downcomer end portion may be axially aligned in a direction parallel to the axial extent of the downcomer end portions. As a result, refrigerant enters the downcomer end portion from at least approximately the same direction. In addition, a flow deflection from the Zulaufrohrleitungsendabschnitten is reduced to the drain pipe end portion to a minimum.

The drain pipe end portion may have a particularly constant flow cross-section, which is at least not substantially reduced, in particular equal to or even greater in comparison with the sum of the individual flow outlet cross sections of the Zulaufrohrleitungsendabschnitte. As a result, it can be achieved that no large, in particular sudden, pressure changes occur in the transitional region from the inlet conduit end sections into the downcomer end section.

In summary, the invention, sometimes in other words, a refrigerant cycle system of a household refrigeration appliance can be improved in particular with regard to injection and flow noise. The refrigeration cycle system according to the invention can be used in particular for cooling of freezer rooms and in fridge / freezer combination devices. In particular, in these devices, a capillary tube in a coming of a refrigerator compartment tube immediately before the freezer open out. The refrigerant cycle system can be connected so that refrigerant is injected either in the refrigerator compartment with downstream freezer or directly into the freezer.

In one embodiment of an injection configuration according to the invention, a tube enclosing the capillary in the course of the capillary tube, which then widens conically, can be inserted into a specially shaped Y-piece into which the connecting tube can then also open. The capillary tube can be located centrally in the injection tube. The flow cross sections are not reduced in advantageous embodiments by the Y-piece and also the flow direction is not significantly deflected.

Also in the connecting pipe, the flow cross sections in the course in the flow direction can not be significantly reduced. As a result, sometimes homogeneous flow conditions can be achieved and consequently flow noise can be reduced.

In one embodiment, the capillary tube may be arranged centrally in the middle of the tube, so that the injection of the refrigerant does not take place in the vicinity of the inner wall of the injection tube, which could, for example, lead to negative detachment effects, which could be associated with noise. Furthermore, in a cylindrical gap between capillary tube and injection tube, the penetration depth of a solder and / or the position of the capillary can be better adjusted and made stable in terms of manufacturing technology.

Further features and advantages of the household refrigerating appliance according to the invention may be apparent from the following description of an exemplary embodiment with reference to the accompanying figures. Concrete features of this embodiment may represent general features of the invention.

Figur 1

eine perspektivische Ansicht eines beispielhaften Haushaltskältegeräts mit einem Kältemittelkreislaufsystem;

Figur 2

eine schematische Darstellung eines erfindungsgemäßen Kältemittelkreislaufsystems mit Kältemittelrohrleitungen;

Figur 3

eine perspektivische Ansicht auf einen Innenbehälter des beispielhaften Haushaltskältegeräts mit einem Y-förmigen Zusammenlauf im Kältemittelkreislaufsystem;

Figur 4a

eine perspektivische Ansicht des Y-förmigen Zusammenlaufs mit einer Art von Rohrverbindungsmuffe;

Figur 4b

eine Querschnittsansicht eines kapillaren Zulaufrohrleitungsendabschnitts, der an die Rohrverbindungsmuffe angeschlossen ist.

Show it:

FIG. 1

a perspective view of an exemplary household refrigerator with a refrigerant cycle system;

FIG. 2

a schematic representation of a refrigerant circuit system according to the invention with refrigerant pipelines;

FIG. 3

a perspective view of an inner container of the exemplary household refrigerator with a Y-shaped convergence in the refrigerant cycle system;

FIG. 4a

a perspective view of the Y-shaped convergence with a type of pipe connection sleeve;

FIG. 4b

a cross-sectional view of a capillary Zulaufrohrleitungsendabschnitts which is connected to the pipe connection sleeve.

An in Fig. 1 household refrigerating appliance 1 shown by way of example has a body 2 with an inner container 3. The inner container 3 is divided into a freezer compartment 4 arranged at the top and a cooling compartment 5 arranged at the bottom. The freezer compartment 4 is generally used for freezing frozen food at about minus 18 degrees Celsius. The freezer compartment 4 is associated with a first evaporator 6, which is arranged behind a freezer compartment rear wall 7. The freezer compartment 4 is accessible when the freezer compartment door 9 is open. To open, the freezer compartment door 9 has a first handle 10.

The cooling space 5 is generally used for frost-free cooling of refrigerated goods, preferably at temperatures between plus 4 and plus 8 degrees Celsius. However, the cooling space 5 can also be designed as a zero-degree compartment, in particular for keeping fruit or vegetables fresh. The refrigerator compartment 5 has a rear wall 11, behind which the first evaporator 6 for the freezer compartment 4 is arranged. A second evaporator 12 serves to cool the cooling space 5. The cooling space 5 is accessible when the refrigerator door 14 is open. To open the refrigerator door 14 has a second handle 15.

A single evaporator, or the first evaporator 6 and the second evaporator 12, or any number of evaporators may be connected to a compressor 8. The compressor 8 is inserted from the rear side, ie behind the rear wall 11 of the refrigeration device 1 into a machine room 13 of the housing 16.

In the Fig. 2 an exemplary embodiment of a refrigerant circuit system 17 is shown schematically. The refrigerant cycle system 17 has a compressor 8, a condenser 19, and a first evaporator 6 and a second evaporator 12. Each evaporator 6, 12, a first uncontrolled expansion valve 18, for example, as a throttle 18a and a second uncontrolled expansion valve 18, for example, as a throttle 18b fluidly upstream. The compressor 8, the condenser 19, the evaporator 6, 12 and the throttles 18a, 18b are fluidically through refrigerant pipelines 20, as in Fig. 2 illustrated, interconnected.

After the compressed by the compressor 8 and then cooled by the condenser 19 and liquefied refrigerant exiting the condenser 19, the refrigerant is supplied in the illustrated embodiment via a refrigerant pipe 20.2 a switching device 21. Via the switching device 21, the refrigerant is supplied either via a refrigerant pipe 20.3 and via a throttle 18a to the first evaporator 6 or via a different refrigerant pipe 20.4 and a second throttle 18b supplied to the second evaporator 12.

The first evaporator 6 may, for example, be coupled to the cooling space 5 and the second evaporator 12 may be coupled to the freezing space 4 by refrigeration. In a first operating mode, in which the refrigerant is supplied by the switching device 21 via the refrigerant pipe 20.3 and the throttle 18a to the first evaporator 6, first the cooling chamber 5 and connected in series, fed via the refrigerant pipe 20.6 the second evaporator 12, the the freezer compartment 4 is coupled refrigeration technology. Thus, first, the cooling chamber 5 and then the freezer compartment 4 is cooled by the refrigerant. In a second operating mode, only the freezer compartment 4 and not the refrigerator compartment 5 is cooled. In this second mode of operation, in which the refrigerant is discharged directly through the switching device 21 via the refrigerant piping 20.4 and via the throttle 18b, i. is supplied to the second evaporator 12 bypassing the first evaporator 6, the refrigerant is supplied via the refrigerant pipe 20.5 to the second evaporator 12.

In order to be able to operate the household refrigerating appliance 1 selectively in one of the two operating modes, the refrigerant pipelines 20.5 and 20.6 are fed to a common refrigerant piping 20.7.

In the exemplary embodiment, the refrigerant pipe 20.6 has a feed pipe end section 20a and the refrigerant pipe 20.5 has an inlet pipe end section 20b. The two inlet pipe end portions 20a and 20b open into a downcomer end portion 20c of the refrigerant pipe 20.7.

In the Fig. 3 For example, the supply pipe end portions 20a, 20b and the downcomer end portion 20c are enlarged. The Fig. 3 shows a perspective section of the inner container 3 with the coolable interior spaces, ie the freezer compartment 4 and the cooling chamber 5. The inlet pipe end portion 20b is designed as a capillary 22 in the illustrated embodiment.

In the Fig. 4a and Fig. 4b is shown by way of example closer, as the inlet pipe end portion 20b has a widening in the flow cross section pipe section 30. In the exemplary embodiment, the feed pipe end section 20b is formed by a capillary 22, to which the pipe section 30 widening in the flow cross-section adjoins. The pipe section 30 may be part of a pipe connection sleeve 31 having a tube section 32. As in Fig. 4b Shown in cross section, the capillary 22 is inserted into the tube portion 32 and connected thereto. The tube section 32 then in turn opens into the tube section 30 which widens in the flow cross-section.

The pipe section 30 widening in the flow cross-section widens continuously in the exemplary embodiment. The expanding in the flow cross-section pipe section 30 is also formed conically widening.

As in particular in Fig. 4a illustrated, the feed pipe end portion 20b between the expanding in the flow section pipe section 30 and an exit-side end 33 of the Zulaufrohrleitungsendabschnitts 20b, an end pipe section 34 with constriction-free, in particular constant or even increasing flow cross-sectional course.

The pipe section 30 widening in the flow cross section is designed to widen up to a constant outflow cross section of the end pipe section 34. The outflow cross section of the end pipe section 34 can be a the Ausströmquerschnitt of have another outflow cross-section corresponding to another feed pipe end section 20a.

In the illustrated embodiment, the pipe section 30 widening in the flow cross section has a circular flow cross section. The pipe section 30, which widens in the flow cross-section, is adjoined by a hollow cylindrical end pipe section 34. The flow section widening pipe section 30 is formed on the separate pipe connection sleeve 31. The pipe connection sleeve 31 is attached to the feed pipe end portion 20b and to the capillary 22, in particular soldered.

Like in the Fig. 4b the pipe section 30 widening in the flow cross-section is aligned coaxially with the feed pipe end section 20b or the capillary 22. The capillary 22 protrudes inside the pipe connection sleeve 31 into the conically widening pipe section 30. The two inlet pipe end portions 20a and 20b are inserted parallel to each other in the drain pipe end portion 20c. The drain pipe end portion 20c is arranged axially aligned in a direction parallel to the axial extent of the Zulaufrohrleitungsendabschnitte 20a and 20b direction.

Claims (12)

1. Domestic refrigerator having at least one thermally-insulated inner container (3) with a coolable interior (4, 5), and a refrigerant circulation system (17) embodied for cooling the interior (4, 5), having at least one compressor (8), a condenser (19), and an evaporator (6, 12) which are connected by refrigerant pipelines (20.1 - 20.8) in order to form the refrigerant circulation system (17) of which at least two refrigerant pipelines (20.1 - 20.8) each have an inlet pipeline end section (20a, 20b) and of which a further refrigerant pipeline (20.1 - 20.8) has an outlet pipeline end section (20c), into which the two inlet pipeline end sections (20a, 20b) run, characterised in that at least one of the two inlet pipeline end sections (20a, 20b) has a pipeline section (30) expanding in its flow cross-section.
2. Domestic refrigerator according to claim 1, characterised in that the inlet pipeline end section (20a, 20b), between the pipeline section (30) expanding in its flow cross section and an outlet side end (33) of the inlet pipeline end section (20a, 20b) or a pipeline connection coupling (31), has a constriction-free, especially constant or even increasing flow cross-section course.
3. Domestic refrigerator according to claim 1 or 2, characterised in that the pipeline section (30) expanding in its flow cross-section is embodied as continuously, especially conically, expanding.
4. Domestic refrigerator according to one of claims 1 to 3, characterised in that the pipeline section (30) expanding in its flow cross-section is embodied as expanding up to a constant outflow cross-section, especially an outflow cross-section corresponding to the outflow cross-section of the other inlet pipeline end section (20a, 20b).
5. Domestic refrigerator according to one of claims 1 to 5, characterised in that the pipeline section (30) expanding in its flow cross-section has a circular flow cross-section, and/or a hollow cylinder, especially a circular hollow cylindrical end pipeline section (34), adjoins the pipeline section (30) expanding in its flow cross-section.
6. Domestic refrigerator according to one of claims 1 to 5, characterised in that the pipeline section (30) expanding in its flow cross-section is embodied on a separate pipeline connection coupling (31) which is fastened, especially soldered, to the inlet pipeline end section (20a, 20b).
7. Domestic refrigerator according to one of claims 1 to 6, characterised in that the pipeline section (30) expanding in its flow cross-section is aligned coaxially to the inlet pipeline end section (20a, 20b).
8. Domestic refrigerator according to one of claims 1 to 7, characterised in that the inlet pipeline end section (20a, 20b) is formed by a capillary (22) to which the pipeline section (30) expanding in its flow cross-section is connected, especially to which capillary (22) a small pipeline section (32) of a pipeline connection coupling (31) is connected which features the pipeline section (30) expanding in its flow cross-section.
9. Domestic refrigerator according to claim 8, characterised in that the capillary (22) projects within the pipeline connection coupling (31) into the conically-expanding tube section (30).
10. Domestic refrigerator according to one of claims 1 to 9, characterised in that the two inlet pipeline end sections (20a, 20b) are inserted running in parallel to one another into the outlet pipeline end section (20c).
11. Domestic refrigerator according to one of claims 1 to 10, characterised in that outlet pipeline end section (20c) is aligned axially in a direction parallel to the axial extent of the inlet pipeline end sections (20a, 20b).
12. Domestic refrigerator according to one of claims 1 to 11, characterised in that outlet pipeline end section (20c) has an especially constant flow cross-section, which, by comparison with the sum of the individual flow outlet cross-sections of the inlet pipeline end sections (20a, 20b), at least does not reduce significantly, in particular is the same size or even larger.

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