EP0703421B1 - Refrigerated cabinet with at least two compartments having different temperatures - Google Patents

Description

The invention relates to a refrigerator according to the preamble of Claim 1.

Such a refrigerator is e.g. known from FR-A-2 652 150.

DE-OS 35 08 805 is a two-temperature refrigerator known, the thermally separated subjects different Temperature cooled by one evaporator each are in a refrigeration cycle with a single compressor lie and controlled by this as heatable chokes trained control bodies depending on the cooling requirements in the subjects either one after the other or simultaneously with liquid refrigerant can be applied. To be sufficient To provide the amount of refrigerant in the latter case and at the same time a refrigerant overfill in single operation Avoiding the evaporator is on the pressure side of the compressor a collector downstream, which is similar to a dead end trained connection line to the pressure line of the compressor is connected and which a heating element for Expulsion of the liquid stored in its collection space Refrigerant is assigned. In the event that for the subjects Refrigeration demand is signaled with a lead time the collector before commissioning the compressor assigned heating element activated, then the saved supply liquid refrigerant to the refrigerant circuit.

Another two-temperature cooling device is from DE-OS 40 20 537 known, the thermally separated cold compartments different temperature in series within one equipped with a single compressor Refrigeration circuit and depending on the cooling requirement, controlled by lockable Throttling devices each individually or together are charged with refrigerant, the amount of refrigerant is matched to the filling quantity of the two evaporators. If cooling demand is only signaled for one of the two cooling compartments, so that is available in the entire refrigeration circuit Refrigerant amount to overfill one at a time to avoid operating evaporator by using an over one Throttle valve can be tapped off the condenser accordingly divided the capacity of this evaporator. As a result the liquefier will only be tapped before this Tapping section from that through the compressor circulated refrigerant flows.

Both refrigeration circuits that have become known from the prior art allow a need based on the respective evaporator Tailored control of the amount of refrigerant, but adheres the system known from DE-OS 35 08 805 the disadvantage indicates that when there is a cooling requirement for both compartments an energy-intensive one temporal reserve for heating the collector before starting the compressor is necessary to the liquid Expel refrigerant from the collector and the refrigeration cycle to provide. The known from DE-OS 40 20 537 Technology is disadvantageous in that the condenser at a refrigeration request from only one of the cooling compartments at all times proportionate flow of refrigerant and thus its surface area required for heat exchange significantly reduced is what causes the compressor runtimes and thus the energy consumption of the device significantly.

The invention has for its object in a refrigerator propose measures according to the preamble of claim 1, due to which the optimal for cooling the individual compartments Refrigerant amount is always provided and there at the same time avoided the disadvantages of the prior art are.

This object is achieved according to the invention by the characteristics of the characteristic part of the Claim 1 solved.

The solution according to the invention ensures that at a refrigeration requirement for all subjects Amount of refrigerant immediately after the refrigeration requirement is signaled available to the refrigeration circuit without time reserve stands. Furthermore, the entire surface of the condenser is always acted as a heat exchange surface, so that especially when underfilled operated refrigeration cycle the compressor running times and thus the energy consumption of the refrigerator is significantly reduced are. In addition, energy-intensive heaters can There is no need to expel the refrigerant from the collector.

According to a preferred embodiment corresponds to the capacity of the reservoir at least the liquid volume of the refrigerant circuit to control the temperature of the storage compartments to withdraw liquid refrigerant.

According to a further preferred embodiment of the object the invention provides that that for receiving liquid refrigerant reservoir and this in the Refrigerant circuit to be used to divert the Condenser is connected downstream.

The advantage of such a solution is on the one hand that on expensive thermal insulation measures to prevent the heat flow from the compressor to the collector to the collector function, namely the condensation of the gas phase existing refrigerant, ensure largely eliminated can. On the other hand, in such an embodiment the refrigerant in the liquid phase before and is therefore immediately available for refrigeration.

According to an alternative embodiment of the object the invention with which an additional possibility is created is, any structural conditions that may arise to take into account on the refrigerator, it is provided that the reservoir used to hold liquid refrigerant and the deflection element used to integrate it into the refrigeration circuit arranged between the compressor and the condenser is.

According to a further preferred embodiment of the object the invention provides that the deflecting the for holding liquid refrigerant reservoir is connected upstream on the input side.

Such a solution is a direct redirection of the Refrigerant without the formation of additional, not for refrigerant storage intended collection points achieved.

It is particularly easy to redirect the refrigerant flow through the deflector if after a next one advantageous embodiment of the subject of the invention it is provided that the deflector as a 3/2-way valve is trained.

A 3/2-way valve is particularly expedient, if after a next preferred embodiment of the object the invention provides that the 3/2-way valve as a bistable electrically controllable solenoid valve is trained.

The solenoid valve is particularly precisely timed and controlled as required, if according to a further preferred embodiment the object of the invention is provided that the electrically controllable solenoid valve by an electrical evaluation circuit depending on the higher in the subject Storage temperature by a temperature sensor and temperature controlled by the evaluation circuit is controlled.

According to a further particularly advantageous embodiment of the The object of the invention is that for cooling of compartments of different temperature serving evaporators arranged in series with each other within the refrigeration circuit are and a cooling capacity falling in the refrigerant flow direction exhibit.

According to an alternative embodiment of the object the invention provides that for cooling the compartments different temperature evaporators inside the refrigeration circuit arranged in parallel to each other are.

Fig. 1

ein Drei-Temperaturzonen aufweisendes Haushaltskühlgerät mit übereinander angeordneten, thermisch voneinander getrennten und durch separate Türen verschließbaren Fächern, in raumbildlicher Darstellung von vorne,

Fig. 2

in schematischer Darstellung den zur Kühlung der Fächer dienenden Kältekreis mit einer für seine Regelung vorgesehenen Elektronik.

The invention is explained in the following description with reference to a three-temperature cooling device shown in simplified form in the accompanying drawing. Show it:

Fig. 1

a three-temperature zone household refrigerator with compartments arranged one above the other, thermally separated and closable by separate doors, in a spatial representation from the front,

Fig. 2

a schematic representation of the cooling circuit used to cool the compartments with electronics provided for its regulation.

In Fig. 1, a household refrigerator 10 is shown, on the heat-insulating housing 11 three about vertical axes of rotation pivotable doors 12 to 14 are hinged. These serve to close one another by two mutually spaced partitions 15 and 16 produced and through these thermally separated compartments 17 to 19, which have different storage temperatures. Of the compartments 17 to 19 is the overhead one with the door 12 lockable compartment 17 as normal refrigerator compartment, the middle, separated by the partition 15 and through the door 13 coverable compartment 18 designed as a cold storage compartment, while the one below, through the partition 16 from the cold storage compartment 18 thermally separated compartment 19 serves as a freezer compartment and can be closed with the door 14. Those in the individual subjects 17 to 19 prevailing subject-specific storage temperature is generated and maintained by a single refrigeration circuit 20.

As can be seen in particular from FIG. 2, the cooling circuit 20 to maintain the temperature in the individual compartments 17 to 19 with three connected in series within the refrigeration circuit arranged in a row, with different Cooling capacity equipped evaporators 21 to 23, of which the evaporator with the highest cooling capacity 21 is assigned to the freezer compartment 19 and an injection point for the refrigerant. The freezer evaporator 21 is the outlet side in the refrigerant flow direction Cooling of the cold storage compartment 18 serving evaporator 22, at which the normal refrigerator compartment 17, the lowest cooling capacity evaporators 23 connects. This is on the outlet side to the suction side of a refrigerant compressor 24, which pressure side A condenser 25 is connected downstream in the refrigerant flow direction is, for example, on that of the doors 12 to 14 facing away from the rear of the housing 11 is arranged. On the condenser 25 closes on the outlet side with hygroscopic Material equipped dryer cartridge 26, which serves the purpose of filling the cooling circuit resulting residual water content from the liquid refrigerant to absorb. The dryer cartridge 26 is on the output side connected to the entrance of a deflection member 27. This is in the In the present case as a bistable 3/2-way solenoid valve formed, which in its switching position 1 a flow path for the refrigerant between the outlet of the dryer cartridge 26 and the input designed as an injection point of the freezer compartment evaporator 21. In his other Switch position 0 connects the solenoid valve 27 to Output of the dryer cartridge 26 with the input of one for recording of liquid refrigerant serving reservoir 28, which on the output side with the switch position 1 of the Solenoid valve 27 controllable, to the freezer evaporator 21 leading refrigerant line is connected so that Via the electromagnetic valve 27, the reservoir 28 into the refrigerant flow can be coupled.

The change of the switching positions of the solenoid valve 27 conditional control signals are not from one in detail described evaluation and control electronics 30 generated, and via a signal line 31 to the solenoid valve 27 fed. Furthermore, the evaluation and control electronics 30 each in the normal refrigerator compartment 17 or in the cold storage compartment 18 prevailing storage temperature, with this in the air temperature in both compartments is an NTC sensor sensing element 32 is provided, which each via a signal line 33 or 34 for data transmission connected to the evaluation and control electronics 30 is. The evaluation and control electronics 30 also serves to control the internal clearance in the cold storage compartment 18 circulating fan 35, which for the purpose of its control via a control line 36 with the evaluation and Control electronics 30 is connected, via which the operation of the compressor 24 is controlled, for which one the evaluation and control electronics 30 with the compressor 24 connecting control line 37 is provided.

When the cooling device 10 is in operation, the operation of the only compressor 24 arranged in its refrigeration circuit 20 by the prevailing in the cold storage compartment 18 and of the therein arranged sensor element 32 determines the detected storage temperature, their corresponding voltage signals via the signal line 34 of the evaluation and control electronics 30 is supplied are through which on the control line 37 when reaching the temperature limit values for the storage temperature in Cold storage compartment 18 of the compressor 24 activated or deactivated becomes. The driven by the compressor 24 in the refrigeration cycle 20 circulated liquid refrigerant amount is dependent the one prevailing in the cooling compartment 17, from the NTC sensor detected and via the signal line 33 of the evaluation and control electronics 30 transmitted temperature controlled, wherein this when the temperature falls below a predetermined limit in the refrigerator compartment 17, the solenoid valve 27 via the signal line 31 switched to its switching position 1, so that reservoir 28 serving as a liquid refrigerant collector is no longer flowed through by the refrigerant. This will make it Reservoir 28 colder than that opposite to the refrigerant flow direction upstream condenser 25, whereby liquid refrigerant accumulates in the reservoir 28, which with respect its capacity at least the volume of liquid the refrigeration circuit 20 for temperature control the amount of liquid refrigerant to be extracted from the storage compartments corresponds. In this way, the refrigeration circuit 20 is underfilled operated, such an underfill especially that is at the bottom of the evaporator series connection Refrigerator evaporator 23 makes noticeable, which due to the solenoid valve position is depleted of liquid refrigerant, so that the temperature in the normal refrigerator compartment 17 rises. Exceeds the temperature in the normal refrigerator compartment 17 due to the in the Evaporator 23 depletion of liquid refrigerant the upper temperature limit so this is using of the NTC sensor 32 of the evaluation and control electronics 30 signals, whereupon these controls the solenoid valve 27 into its switching position 0.

In this switching position, the reservoir 28 is in the cooling circuit 20 involved and thus flows through it Amount of liquid refrigerant accumulated in the refrigerant circuit 20 arrives and for cooling the storage compartments 17 to 19 of the cooling device 10 is available.

Contrary to the embodiment described above can also, as shown by dashed lines, accordingly an alternative embodiment of the object the invention provide that the deflection 27th Serving solenoid valve together with this in the Refrigeration circuit 20 can be coupled to the reservoir 28 and the condenser 25 is connected upstream.

Instead of being arranged in series in the refrigeration circuit 20 Evaporator (21, 22, 23), the invention can also be in parallel Use switched vaporizers, taking care to separate them A corresponding circuit is applied to the refrigerant to be provided with electrically controllable solenoid valves is.

Claims (10)

1. Cooling appliance with at least two compartments of different temperature, the evaporators (21, 22, 23) of which together with a compressor (24) and a condenser (25), lie in a cooling circuit and are loaded with liquid refrigerant, the refrigerant quantity of which contributing to production of cooling is controllable, by the compressor (24) when a cooling requirement of the compartments is signalled, wherein for control of the refrigerant quantity a reservoir (28) serving for reception of liquid refrigerant is connected in the refrigerant circuit (20) downstream of the compressor (24) at the pressure side and can be coupled into the refrigerant circuit by a diverter (27), characterised in that the reservoir (28) in the coupled-in state is flowed through in such a manner that the refrigerant quantity accumulated therein passes into the refrigerant circuit (20) and that the reservoir (28) in the decoupled state is flowed around with the aid of a flow path in the manner of bypassing.
2. Cooling appliance according to claim 1, characterised in that the reservoir (28) corresponds with respect to its holding capacity at least to the liquid volume of the liquid refrigerant quantity to be withdrawn to the refrigerant circuit (20) for the temperature control of the storage compartments (17, 18, 19).
3. Cooling appliance according to claim 1 or 2, characterised in that the reservoir (28) serving for reception of liquid refrigerant and the diverter (27) serving for coupling thereof into the refrigerant circuit (20) are arranged downstream of the condenser (25).
4. Cooling appliance according to claim 1 or 2, characterised in that the reservoir (28) serving for reception of liquid refrigerant and the diverter (27) serving for connection thereof into the refrigerant circuit (20) are arranged between the compressor (24) and the condenser (25).
5. Cooling appliance according to one of claims 1 to 4, characterised in that the diverter (27) is connected upstream and at the inlet side of the reservoir (28) serving for reception of liquid refrigerant.
6. Cooling appliance according to one of claims 1 to 5, characterised in that the diverter (27) is constructed as a 3/2-way valve.
7. Cooling appliance according to claim 6, characterised in that the 3/2-way valve is constructed as a bistable electrically controllable magnetic valve (27).
8. Cooling appliance according to claim 7, characterised in that the electrically controllable magnetic valve (27) is controlled by an electrical evaluating circuit (30) in dependence on the temperature detected in the compartment (23) with the higher storage temperature by a temperature sensor (32) and evaluated by the evaluating circuit (30).
9. Cooling appliance according to claim 1, characterised in that the evaporators (21, 22, 23) serving for the cooling of the compartments (17, 18, 19) of different temperature are arranged within the cooling circuit (20) in series connection to one another and have a cooling power falling in the refrigerant flow direction.
10. Cooling appliance according to claim 1, characterised in that the evaporators (21, 22, 23) serving for the cooling of the compartments (17, 18, 19) of different temperature are arranged within the cooling circuit in parallel connection to one another.

Images