CN219713696U - Cascade refrigerating system and refrigerating equipment - Google Patents

Abstract

The utility model provides an cascade refrigeration system and refrigeration equipment. The utility model aims to solve the problem that the refrigerating sequence of different storage compartments cannot be determined when the existing refrigerating equipment with the cascade refrigerating system simultaneously refrigerates a plurality of storage compartments. The system comprises a high-temperature-level refrigerating system and a low-temperature-level refrigerating system, wherein the high-temperature-level refrigerating system is used for refrigerating the low-temperature-level refrigerating system; the high-temperature-stage refrigeration system comprises a high-temperature-stage compressor, a high-temperature-stage condenser, a first control valve, a refrigeration depressurization component, a refrigeration evaporator, a second control valve, a high-temperature-stage heat exchange component and a third control valve which are sequentially connected in series and form a closed loop; the low-temperature-stage refrigeration system comprises a low-temperature-stage heat exchange component connected in series between an outlet of the low-temperature-stage compressor and an inlet of the low-temperature-stage depressurization component; the low-temperature-stage heat exchange component is thermally connected with the high-temperature-stage heat exchange component, so that the high-temperature-stage heat exchange component absorbs heat of the low-temperature-stage heat exchange component. The utility model improves the refrigerating efficiency of the refrigerating equipment.

Description

Cascade refrigerating system and refrigerating equipment

Technical Field

The utility model belongs to the technical field of refrigeration equipment, and particularly provides a cascade refrigeration system and refrigeration equipment.

Background

Currently, in order to meet the storage requirements of food materials in a refrigeration apparatus, the refrigeration apparatus is generally configured with a plurality of storage compartments having different storage conditions, specifically including a refrigeration storage compartment, a freezing storage compartment, a temperature-variable storage compartment, or a very low temperature storage compartment (i.e., the temperature interval of the very low temperature storage compartment is smaller than the temperature intervals of the refrigeration storage compartment, the freezing storage compartment, and the temperature-variable storage compartment). In order to improve the refrigerating efficiency of different storage compartments in the refrigerating apparatus, the refrigerating system in the refrigerating apparatus is generally configured into two relatively independent refrigerating systems (i.e., cascade refrigerating systems) so as to meet the storage conditions required by the different storage compartments.

In the conventional cascade refrigeration system, when a plurality of storage compartments need to be simultaneously cooled, a method of switching the cooling operation in turn (about once every twenty minutes) is generally adopted to cool the plurality of storage compartments, but it is not possible to prioritize the simultaneous cooling operation of the plurality of storage compartments. Since the very low temperature compartment temperature in the refrigeration appliance is relatively low, the rate of leakage of cold is often greater for the outside than for the refrigerated and frozen compartments where the temperature is relatively high, and in comparison, the temperature of the leakage of cold is also relatively low for the very low temperature compartment and the value of the cold is also higher.

Accordingly, there is an urgent need for an cascade refrigeration system capable of preferentially cooling a relatively low-temperature storage compartment to improve the refrigeration efficiency of a refrigeration apparatus having the refrigeration system.

Disclosure of Invention

An object of the present utility model is to solve the problem that when a plurality of storage compartments are simultaneously cooled by a conventional refrigeration apparatus having a cascade refrigeration system, the cooling sequence of the different storage compartments cannot be determined.

In order to achieve the above object, the present utility model provides an cascade refrigeration system, which comprises a high-temperature-stage refrigeration system and a low-temperature-stage refrigeration system, wherein the high-temperature-stage refrigeration system is used for refrigerating the low-temperature-stage refrigeration system;

the high-temperature-stage refrigeration system comprises a high-temperature-stage compressor, a high-temperature-stage condenser, a first control valve, a refrigerating depressurization member, a refrigerating evaporator, a second control valve, a high-temperature-stage heat exchange member and a third control valve which are sequentially connected in series and form a closed loop, and further comprises a high-temperature-stage depressurization member connected in series between the first control valve and the second control valve;

the low-temperature-stage refrigerating system comprises a low-temperature-stage compressor, a low-temperature-stage condenser, a low-temperature-stage depressurization member and a low-temperature-stage evaporator which are sequentially connected in series and form a closed loop, and further comprises a low-temperature-stage heat exchange member connected in series between an outlet of the low-temperature-stage compressor and an inlet of the low-temperature-stage depressurization member; the low-temperature-stage heat exchange member is thermally connected with the high-temperature-stage heat exchange member so that the high-temperature-stage heat exchange member absorbs heat of the low-temperature-stage heat exchange member.

Further, the high temperature stage refrigeration system further comprises a refrigeration evaporator connected in series between the outlet of the third control valve and the inlet of the high temperature stage compressor; the high temperature stage pressure reducing member is fluidly connected by its outlet to the inlet of the freeze evaporator.

Further, the high temperature stage refrigeration system further includes an auxiliary depressurization member and an auxiliary evaporator serially connected in sequence between the first control valve and the third control valve.

Further, the first control valve is a four-way reversing valve with one inlet and three outlets, the first control valve is in fluid connection with the outlet of the high-temperature-stage condenser through the inlet of the first control valve, and the first control valve is in fluid connection with the inlet of the high-temperature-stage depressurization member, the inlet of the refrigeration depressurization member and the inlet of the auxiliary depressurization member through the three outlets of the first control valve; and/or the number of the groups of groups,

the second control valve is a four-way reversing valve with two inlets and two outlets, the second control valve is respectively in fluid connection with the outlet of the refrigeration evaporator and the outlet of the high-temperature-stage depressurization member through the two inlets of the second control valve, and the second control valve is respectively in fluid connection with the inlet of the high-temperature-stage heat exchange member and the inlet of the high-temperature-stage compressor through the two outlets of the second control valve; and/or the number of the groups of groups,

the third control valve is a four-way reversing valve with one inlet and three outlets, the third control valve is in fluid connection with the outlet of the high-temperature-stage heat exchange component through the inlet of the third control valve, and the third control valve is in fluid connection with the inlet of the refrigeration evaporator, the inlet of the freezing evaporator and the inlet of the high-temperature-stage compressor through the three outlets of the third control valve.

Further, at least one of the refrigerating step-down member, the high-temperature-stage step-down member, the auxiliary step-down member, and the low-temperature-stage step-down member is a capillary tube.

Further, the cascade refrigeration system is used for refrigeration equipment.

Further, the refrigeration equipment comprises a box body and a cascade refrigeration system, wherein a high-temperature-level storage compartment, a high-temperature-level refrigeration compartment, a low-temperature-level storage compartment and a low-temperature-level refrigeration compartment are defined in the box body; the high temperature stage storage compartments include a refrigerated storage compartment; the high-temperature-stage refrigeration compartment includes a refrigeration compartment in communication with the refrigeration storage compartment, the refrigeration evaporator being disposed within the refrigeration compartment.

Further, the high temperature stage storage compartment further comprises a refrigeration storage compartment, the high temperature stage refrigeration compartment further comprises a refrigeration compartment in communication with the refrigeration storage compartment, the high temperature stage refrigeration system further comprises a refrigeration evaporator in series between the outlet of the third control valve and the inlet of the high temperature stage compressor, the refrigeration evaporator being disposed within the refrigeration compartment.

Further, the high-temperature-stage refrigeration system further includes an auxiliary depressurization member and an auxiliary evaporator, which are sequentially connected in series between the first control valve and the third control valve, the auxiliary evaporator being disposed within the low-temperature-stage refrigeration compartment.

Further, the refrigeration appliance is a refrigerator.

Based on the foregoing description, it will be appreciated by those skilled in the art that in the foregoing technical solution of the present utility model, by arranging the high-temperature-stage refrigeration system in the cascade refrigeration system to include the high-temperature-stage compressor, the high-temperature-stage condenser, the first control valve, the refrigeration depressurization member, the refrigeration evaporator, the second control valve, the high-temperature-stage heat exchange member, and the third control valve, which are sequentially connected in series and form a closed loop, the high-temperature-stage depressurization member connected in series between the first control valve and the second control valve is further included such that one outlet of the third control valve is fluidly connected with one inlet of the refrigeration evaporator, thereby enabling the refrigerant in the system to flow along the following path: high temperature stage compressor- & gthigh temperature stage condenser- & gtfirst control valve- & gthigh temperature stage depressurization component- & gtsecond control valve- & gthigh temperature stage heat exchange component- & gtthird control valve- & gtrefrigeration evaporator- & gtsecond control valve- & gthigh temperature stage compressor. Meanwhile, a low-temperature-level refrigerating system in the cascade refrigerating system is arranged to be a low-temperature-level compressor, a low-temperature-level condenser, a first heat exchange component, a low-temperature-level depressurization component and a low-temperature-level evaporator which are sequentially connected in series and form a closed loop. The high-temperature-level heat exchange component and the low-temperature-level heat exchange component are thermally connected, so that the refrigerant can flow through the high-temperature-level heat exchange component and then flow through the refrigeration evaporator instead of the refrigeration evaporator, and the cascade refrigeration system can refrigerate the extremely-low-temperature storage compartment preferentially and refrigerate the refrigeration storage compartment after simultaneously refrigerating the refrigeration storage compartment and the extremely-low-temperature storage compartment. Therefore, the utility model solves the problem that the existing refrigeration equipment with the cascade refrigeration system cannot refrigerate the extremely low-temperature storage compartments with relatively low temperature preferentially when simultaneously refrigerating a plurality of storage compartments, and improves the refrigeration efficiency of the refrigeration equipment.

Further, by fluidly communicating the outlet of the second control valve with the inlet of the high temperature stage heat exchange member, the outlet of the third control valve is fluidly communicated with the suction inlet of the high temperature stage compressor such that refrigerant in the high temperature stage refrigeration system flows along: high temperature stage compressor- & gthigh temperature stage condenser- & gtfirst control valve- & gthigh temperature stage depressurization member- & gtsecond control valve- & gthigh temperature stage heat exchange member- & gtthird control valve- & gthigh temperature stage compressor. The refrigerant only flows through the high-temperature-stage heat exchange component, but not flows through the high-temperature-stage evaporator, so that the cascade refrigeration system can provide cold energy to the extremely-low-temperature storage compartment preferentially when in low-temperature circulation, and the refrigeration efficiency of the refrigeration equipment is further improved.

Further, by communicating the outlet of the second control valve with the inlet of the high temperature stage heat exchange member and the suction inlet of the high temperature stage compressor, respectively, the outlet of the third control valve is communicated with the inlet of the refrigeration evaporator, so that the refrigerant in the high temperature stage refrigeration system flows along the following paths: high temperature stage compressor- & gthigh temperature stage condenser- & gtfirst control valve- & gthigh temperature stage depressurization component- & gtsecond control valve- & gthigh temperature stage heat exchange component- & gtthird control valve- & gtrefrigeration evaporator- & gtsecond control valve- & gthigh temperature stage compressor. The refrigerant flows through the high-temperature-stage heat exchange component and then flows through the freezing evaporator, but does not flow through the refrigerating evaporator, so that the cascade refrigeration system can refrigerate the extremely low-temperature storage compartment preferentially and refrigerates the refrigerating storage compartment again after simultaneously refrigerating the freezing storage compartment and the extremely low-temperature storage compartment, and the refrigeration efficiency of the refrigeration equipment is further improved.

Drawings

In order to more clearly illustrate the technical solution of the present utility model, some embodiments of the present utility model will be described hereinafter with reference to the accompanying drawings. It will be understood by those skilled in the art that components or portions thereof identified in different drawings by the same reference numerals are identical or similar; the drawings of the utility model are not necessarily to scale relative to each other. In the accompanying drawings:

FIG. 1 is a schematic diagram of a refrigeration appliance in some embodiments of the utility model;

FIG. 2 is a side cross-sectional view of a refrigeration equipment cabinet in some embodiments of the utility model;

FIG. 3 is a schematic diagram of the cascade refrigeration system of the present utility model;

FIG. 4 is a schematic diagram of the refrigerant flow of the cascade refrigeration system of the present utility model in a first refrigeration mode;

FIG. 5 is a schematic diagram of the refrigerant flow of the cascade refrigeration system of the present utility model in a second refrigeration mode;

fig. 6 is a schematic diagram of refrigerant flow in a third cooling mode of the cascade refrigeration system of the utility model.

Detailed Description

It should be understood by those skilled in the art that the embodiments described below are only some embodiments of the present utility model, but not all embodiments of the present utility model, and the some embodiments are intended to explain the technical principles of the present utility model and are not intended to limit the scope of the present utility model. All other embodiments, which can be obtained by a person skilled in the art without any inventive effort, based on the embodiments provided by the present utility model, shall still fall within the scope of protection of the present utility model.

It should be noted that, in the description of the present utility model, terms such as "center", "upper", "lower", "top", "bottom", "left", "right", "vertical", "horizontal", "inner", "outer", and the like indicate directions or positional relationships, which are based on the directions or positional relationships shown in the drawings, are merely for convenience of description, and do not indicate or imply that the apparatus or elements must have a specific orientation, be constructed and operated in a specific orientation, and thus should not be construed as limiting the present utility model. Furthermore, the terms "first," "second," and "third" are used for descriptive purposes only and are not to be construed as indicating or implying relative importance.

Furthermore, it should be noted that, in the description of the present utility model, unless explicitly specified and limited otherwise, the terms "mounted," "connected," and "connected" are to be construed broadly, and may be either fixedly connected, detachably connected, or integrally connected, for example; can be mechanically or electrically connected; can be directly connected, can be indirectly connected through an intermediate medium, and can also be communicated with the inside of two elements. The specific meaning of the above terms in the present utility model can be understood by those skilled in the art according to the specific circumstances.

In addition, it should be noted that, in the description of the present utility model, the terms "cooling capacity" and "heating capacity" are two descriptions of the same physical state. That is, the higher the "cooling capacity" of a certain object (for example, evaporator, air, condenser, etc.), the lower the "heat" of the object, and the lower the "cooling capacity" of the object, the higher the "heat" of the object. Some object absorbs the cold and releases the heat, and the object releases the cold and absorbs the heat. A target maintains "cold" or "heat" to maintain the target at a current temperature. "refrigeration" and "heat absorption" are two descriptions of the same physical phenomenon, i.e., a target (e.g., an evaporator) absorbs heat while it is refrigerating.

The structure of the refrigerating apparatus 1000 in some embodiments of the present utility model will be described in detail with reference to fig. 1 to 2. Wherein fig. 1 is a schematic diagram of a refrigeration appliance 1000 in some embodiments of the utility model; fig. 2 is a side cross-sectional view of the cabinet 100 of the refrigeration appliance 1000 in some embodiments of the utility model.

It should be noted that, for convenience of description and for enabling those skilled in the art to quickly understand the technical solution of the present utility model, only the technical features that are relatively strongly related (directly related or indirectly related) to the technical problem and/or the technical concept to be solved by the present utility model will be described hereinafter, and the technical features that are relatively weakly related to the technical problem and/or the technical concept to be solved by the present utility model will not be described in detail. Since the technical features with a weak degree of association belong to common general knowledge in the art, the disclosure of the present utility model will not be insufficient even if the features with a weak degree of association are not described.

As shown in fig. 1, in some embodiments of the utility model, a refrigeration apparatus 1000 includes a cabinet 100 and an cascade refrigeration system 200. The case 100 includes a refrigerating compartment and a storage compartment 110, and the cascade refrigerating system 200 is disposed in the refrigerating compartment for refrigerating the storage compartment 110.

As shown in fig. 2, the case 100 defines therein a high-temperature-stage storage compartment 111, a high-temperature-stage cooling compartment, a low-temperature-stage storage compartment 112, and a low-temperature-stage cooling compartment. The high-temperature-stage storage compartment 111 communicates with the high-temperature-stage cooling compartment, and the low-temperature-stage storage compartment 112 communicates with the low-temperature-stage cooling compartment.

With continued reference to fig. 2, the cascade refrigeration system 200 includes a high temperature stage refrigeration system 210 and a low temperature stage refrigeration system 230. The high-temperature-stage refrigeration system 210 is used for refrigerating the high-temperature-stage storage compartment 111, and the low-temperature-stage refrigeration system 230 is used for refrigerating the low-temperature-stage storage compartment 112. The high temperature stage refrigeration system 210 is configured to provide refrigeration to the low temperature stage refrigeration system 230 such that the high temperature stage refrigeration system 210 is able to provide a lower temperature to the low temperature stage storage compartment 112.

With continued reference to fig. 2, the high temperature stage storage compartment 111 includes a refrigerated storage compartment 1111 and a freezer storage compartment 1112, with both the refrigerated storage compartment 1111 and the freezer storage compartment 1112 being cooled by the high temperature stage refrigeration system 210. Those skilled in the art will appreciate that the high temperature stage storage compartment 111 further includes a variable temperature storage compartment 1113, or that the high temperature stage storage compartment 111 includes any one or any two of a refrigerated storage compartment 1111, a chilled storage compartment 1112, and a variable temperature storage compartment 1113.

Although not shown in the figures, it will be understood by those skilled in the art that the high temperature stage refrigeration compartment includes a refrigeration compartment, a refrigeration compartment. The refrigeration compartment communicates with the refrigerated storage compartment 1111 and the freezer compartment communicates with the freezer storage compartment. The low-temperature-stage storage compartment 112 is cooled by the low-temperature-stage refrigeration system 230 as an extremely low-temperature storage compartment of the refrigeration device 1000.

The construction and operation of the cascade refrigeration system 200 in accordance with some embodiments of the present utility model will now be described with reference to fig. 3-6. FIG. 3 is a schematic diagram of an cascade refrigeration system 200 according to the present utility model; FIG. 4 is a schematic diagram of the refrigerant flow of the cascade refrigeration system 200 of the present utility model in a first refrigeration mode; FIG. 5 is a schematic diagram of the refrigerant flow of the cascade refrigeration system 200 of the present utility model in a second refrigeration mode; fig. 6 is a schematic diagram illustrating the refrigerant flow of the cascade refrigeration system 200 according to the present utility model in a third refrigeration mode.

As shown in fig. 3 to 6, the high temperature stage refrigeration system 210 includes a high temperature stage compressor 211, a high temperature stage condenser 212, a high temperature stage dew prevention pipe 213, a high temperature stage dry filter, a high temperature stage control valve 215, a refrigerating pressure reducing member 2161, a high temperature stage evaporator 217, a high temperature stage heat exchanging member 218, a high temperature stage liquid storage package 219, and a high temperature stage air return pipe 220, which are sequentially connected in series and form a closed loop. The high temperature stage evaporator 217 includes a refrigeration evaporator 2171 and a freeze evaporator 2172. Wherein control valve 215 includes a first control valve 2151, a second control valve 2152, and a third control valve 2153. The refrigerating evaporator 2171 is disposed at the refrigerating compartment for cooling the refrigerating storage compartment 1111. The freeze evaporator 2172 is arranged in series between the outlet of the third control valve 2153 and the inlet of the high temperature stage compressor 211. A high temperature stage pressure reducing member 2162 is disposed in series between first control valve 2151 and second control valve 2152. The high temperature stage pressure reducing member 2162 is fluidly connected by its outlet to the inlet of the freeze evaporator 2172. Wherein a freeze evaporator 2172 is disposed in the freezer compartment for cooling the freezer compartment 1112. The high temperature stage heat exchange member 218 is configured to provide cooling to the low temperature stage storage compartment 112.

With continued reference to fig. 3-6, in other embodiments of the present utility model, high temperature stage evaporator 217 further includes an auxiliary evaporator 2173, auxiliary evaporator 2173 being connected in series between first control valve 2151 and third control valve 2153. High temperature stage refrigeration system 210 also includes an auxiliary pressure reducing member 2163 serially connected in sequence between first control valve 2151 and third control valve 2153. Wherein the auxiliary evaporator 2173 is disposed in the low-temperature-stage refrigerating compartment, the auxiliary evaporator 2173 serves to assist the low-temperature-stage refrigerating system 230 in cooling the low-temperature-stage storage compartment 112.

With continued reference to fig. 3-6, the outlet of high temperature stage compressor 211 is in fluid communication with the inlet of high temperature stage condenser 212, the outlet of high temperature stage condenser 212 is in fluid communication with the inlet of high temperature stage dew point pipe 213, the outlet of high temperature stage dew point pipe 213 is in fluid communication with the inlet of high temperature stage filter drier 214, and the outlet of high temperature stage filter drier 214 is in fluid communication with the inlet of first control valve 2151.

With continued reference to fig. 3-6, the first control valve 2151 is a four-way reversing valve having one inlet and three outlets. The first control valve 2151 includes an inlet, a first outlet, a second outlet, and a third outlet. Wherein the inlet is in fluid communication with the outlet of the high temperature stage dryer filter 214. The first outlet is fluidly connected to an inlet of the refrigerated pressure reducing member 2161, the outlet of the refrigerated pressure reducing member 2161 is fluidly connected to an inlet of the refrigerated evaporator 2171, and the outlet of the refrigerated evaporator 2171 is fluidly connected to an inlet of the second control valve 2152. The second outlet is fluidly connected to an inlet of high temperature stage pressure reducing member 2162, and an outlet of high temperature stage pressure reducing member 2162 is fluidly connected to an inlet of second control valve 2152. The third outlet is fluidly connected to an inlet of an auxiliary depressurization member 2163, an outlet of the auxiliary depressurization member 2163 is fluidly connected to an inlet of an auxiliary evaporator 2173, and an outlet of the auxiliary evaporator 2173 is fluidly connected to an inlet of the high-temperature stage heat exchange member 218.

With continued reference to fig. 3-6, second control valve 2152 is a four-way reversing valve having two inlets and two outlets, second control valve 2152 including a first inlet, a second inlet, a first outlet, and a second outlet. Wherein the first inlet is fluidly connected to the outlet of the refrigeration evaporator 2171 and the second inlet is fluidly connected to the outlet of the high temperature stage pressure reducing member 2162. The first outlet is fluidly connected to an inlet of high temperature stage heat exchange member 218, and the outlet of high temperature stage heat exchange member 218 is fluidly connected to an inlet of third control valve 2153. The second outlet is fluidly connected to a suction inlet of the high temperature stage compressor 211.

With continued reference to fig. 3-6, third control valve 2153 is a four-way reversing valve having an inlet and three outlets, and third control valve 2153 includes an inlet, a first outlet, a second outlet, and a third outlet. Wherein the inlet is in fluid connection with an outlet of the high temperature stage heat exchange member 218. The first outlet is fluidly connected to an inlet of the refrigerated evaporator 2171 and the outlet of the refrigerated evaporator 2171 is fluidly connected to an inlet of the second controller. The second outlet is fluidly connected to an inlet of the freeze evaporator 2172, and an outlet of the freeze evaporator 2172 is fluidly connected to a suction inlet of the high temperature stage compressor 211. The third outlet is fluidly connected to a suction inlet of the high temperature stage compressor 211.

Principle of operation of the high temperature stage refrigeration system 210:

the refrigerant flowing out of the high-temperature-stage compressor 211 is in a high-temperature and high-pressure state, and is cooled when flowing through the high-temperature-stage condenser 212, and is in a low-temperature and high-pressure state. The high-temperature and high-pressure refrigerant flows to at least one of the refrigerating pressure reducing member 2161, the high-temperature-stage pressure reducing member 2162, and the auxiliary pressure reducing member 2163 by the control valve. The refrigerant flowing through the refrigerating pressure reducing member 2161 is expanded by pressure reduction, and is brought into a low-temperature and low-pressure state. The low-temperature and low-pressure refrigerant absorbs heat in the refrigerating evaporator 2171 to be in a high-temperature and low-pressure state, and thus, refrigerates the refrigerating storage compartment 1111 of the refrigerating apparatus 1000. The pressure of the refrigerant flowing through the high-temperature-stage pressure reducing member 2162 is reduced to expand, and the refrigerant is brought into a low-temperature and low-pressure state. The low-temperature low-pressure refrigerant absorbs heat in the refrigeration evaporator 2172 to be in a high-temperature low-pressure state, and thus, cools the refrigeration compartment 1112 of the refrigeration apparatus 1000. The pressure of the refrigerant flowing through the auxiliary pressure reducing member 2163 is reduced to expand, and the refrigerant is brought into a low-temperature and low-pressure state. The low-temperature and low-pressure refrigerant absorbs heat in the auxiliary evaporator 2173 to be in a high-temperature and low-pressure state, and thus, cools the low-temperature-stage storage compartment 112 of the refrigeration apparatus 1000. Finally, when the high-temperature low-pressure gaseous refrigerant flows through the high-temperature stage compressor 211, the gaseous refrigerant is compressed again to a high-temperature high-pressure state.

The above-mentioned state of the refrigerant, that is, the high temperature, low temperature, high pressure, and low pressure of the refrigerant, is a state in which the refrigerant enters the corresponding part or exits the corresponding part, as compared with a state before the refrigerant flows into the corresponding part.

As shown in fig. 3 to 6, the cascade refrigeration system 200 further includes a low-temperature stage refrigeration system 230, and the low-temperature stage storage compartment 112 is cooled by the low-temperature stage refrigeration system 230 as an extremely low-temperature storage compartment of the refrigeration apparatus 1000.

With continued reference to fig. 3-6, the low-temperature stage refrigeration system 230 includes a low-temperature stage compressor 231, a low-temperature stage condenser 232, a first heat exchange member 233, a low-temperature stage dry filter 235, a low-temperature stage depressurization member 236, a low-temperature stage evaporator 237, a low-temperature stage liquid storage bag 238, and a low-temperature stage muffler 239, which are sequentially connected in series and form a closed loop. Wherein the low temperature stage evaporator 237 is disposed in the low temperature stage refrigeration compartment for cooling the very low temperature storage compartment.

The principle of operation of low temperature stage refrigeration system 230:

the refrigerant flowing out of the low-temperature-stage compressor 231 is in a high-temperature and high-pressure state, and is cooled when flowing through the low-temperature-stage condenser 232, and is in a low-temperature and high-pressure state. When the low-temperature and high-pressure refrigerant flows through the low-temperature-stage pressure reducing member 236, the pressure is reduced and the refrigerant expands, thereby changing to a low-temperature and low-pressure state. The low-temperature low-pressure refrigerant absorbs heat in the low-temperature-stage evaporator 237 to become a high-temperature low-pressure state, and thus refrigerates the low-temperature-stage storage compartment 112 (i.e., the very low-temperature compartment) of the refrigeration apparatus 1000. When the high-temperature low-pressure gaseous refrigerant flows through the low-temperature stage compressor 231, the gaseous refrigerant is compressed again to a high-temperature high-pressure state.

With continued reference to fig. 3-6, the low temperature stage refrigeration system 230 further includes a low temperature stage heat exchange member 234 connected in series between the outlet of the low temperature stage compressor 231 and the inlet of the low temperature stage pressure reducing member 236. The low-temperature stage heat exchange member 234 is configured to absorb cold in the high-temperature stage storage compartment 111. Specifically, when the high-temperature-stage storage compartment 111 includes a plurality of compartments, the low-temperature-stage heat exchange member 234 is configured to be able to absorb the cooling capacity of at least one compartment. For example, the low-temperature-stage heat exchange member 234 may absorb only the cooling capacity of the refrigerator compartment 1111, only the cooling capacity of the freezer compartment 1112, and both the refrigerator compartment 1111 and the freezer compartment 1112. The arrangement of the low-temperature stage heat exchange member 234 will be described below by taking the refrigerating compartment 1111 as an example.

In still other embodiments of the present utility model, the low temperature stage heat exchange member 234 is disposed outside the high temperature stage storage compartment 111, and the low temperature stage heat exchange member 234 abuts the high temperature stage heat exchange member 218. Further, the low-temperature stage heat exchange member 234 is located at the bottom side of the high-temperature stage storage compartment 111 (specifically, the refrigerating storage compartment 1111).

Further, the case 100 further includes a heat insulating layer provided at the inner bottom side of the high temperature stage storage compartment 111 (specifically, the refrigerating storage compartment 1111) to insulate the thermal contact between the food material in the high temperature stage storage compartment 111 (specifically, the refrigerating storage compartment 1111) and the high temperature stage heat exchanging member 218 by the heat insulating layer, thereby preventing the low temperature stage heat exchanging member 234 from absorbing the cold energy of the food material and causing the temperature of the food material to be increased and deteriorated.

In addition, the low temperature stage heat exchange member 234 may be disposed at the top side of the high temperature stage storage compartment 111 (particularly, the refrigerating storage compartment 1111) as necessary to prevent the low temperature stage heat exchange member 234 from absorbing the cold energy of the bottom of the high temperature stage storage compartment 111 (particularly, the refrigerating storage compartment 1111), so that the high temperature stage storage compartment 111 (particularly, the refrigerating storage compartment 1111) can cool the food materials therein by the cold energy of the bottom thereof and cool the low temperature stage heat exchange member 234 by the cold energy of the top thereof.

Alternatively, the low-temperature stage heat exchange member 234 may be disposed at the left, right, or rear side of the high-temperature stage storage compartment 111 (specifically, the refrigerating storage compartment 1111) as needed by those skilled in the art.

Although not shown, in still other embodiments of the present utility model, one skilled in the art may also dispose the low-temperature stage heat exchanging member 234 within the high-temperature stage storage compartment 111 (specifically, the refrigerating storage compartment 1111) as desired. And optionally an insulating layer between the low temperature stage heat exchange member 234 and the food material.

With continued reference to fig. 3-6, a low temperature stage muffler 239 in the low temperature stage refrigeration system 230 includes a first pipe segment 2391 and a second pipe segment 2392. The first heat exchange member 233 is thermally coupled to the first pipe segment 2391 as part of the low temperature stage pressure reducing member 236. Illustratively, the first tube segment 2391 and the low temperature stage pressure reducing member 236 are connected together by fins, or the first tube segment 2391 and the low temperature stage pressure reducing member 236 are encased in insulation wool. The second tube segment 2392 is thermally coupled to the low temperature stage heat exchange member 234 as part of a low temperature stage muffler 239. Illustratively, the second tube segment 2392 and the low temperature stage heat exchange member 234 may be connected together by fins, or the second tube segment 2392 and the low temperature stage heat exchange member 234 may be wrapped with insulation wool.

Although not shown, in other embodiments of the present utility model, as in some embodiments described above, the refrigeration apparatus 1000 is an air-cooled refrigeration apparatus, and the refrigeration apparatus 1000 further includes a blower for driving cool air around the high temperature stage evaporator 217 (particularly the refrigerated evaporator 2171) into the high temperature stage storage compartment 111 (particularly the refrigerated storage compartment 1111) to form a flow of cool air. Further, the low temperature stage heat exchange member 234 is disposed in a path along which the refrigerant gas flow flows such that the low temperature stage heat exchange member 234 absorbs cold in the refrigerant gas flow and thus splits the cold into the high temperature stage storage compartment 111 (specifically, the refrigerating storage compartment 1111).

Further, the high temperature stage heat exchange member 218 and the low temperature stage heat exchange member 234 in the present utility model may be any viable members, such as pipe fittings and hollow members, etc., and those skilled in the art may configure each of the high temperature stage heat exchange member 218 and the low temperature stage heat exchange member 234 as any one of pipe fittings and hollow members, or configure each of the high temperature stage heat exchange member 218 and the low temperature stage heat exchange member 234 as pipe fittings and hollow members, respectively, as required. Preferably, the present utility model configures both the high temperature stage heat exchange member 218 and the low temperature stage heat exchange member 234 as tubes.

As shown in fig. 4-6, in some embodiments of the utility model, the high temperature stage refrigeration system 210 has three modes of refrigeration.

As shown in fig. 4, when the refrigeration system is operating in the first refrigeration mode, the first control valve 2151 places the high temperature stage condenser 212 in communication with the high temperature stage pressure reducing member 2162 and places the high temperature stage condenser 212 out of communication with the refrigerated pressure reducing member 2161, the auxiliary pressure reducing member 2163. The second control valve 2152 communicates the outlet of the high temperature stage pressure reducing member 2162 with the inlet of the high temperature stage heat exchange member 218, the suction inlet of the high temperature stage compressor 211. The third control valve 2153 places the outlet of the high temperature stage heat exchange member 218 in communication with the inlet of the refrigeration evaporator 2171 and places the outlet of the high temperature stage heat exchange member 218 out of communication with the inlet of the refrigeration evaporator 2172 and the suction inlet of the high temperature stage compressor 211. At this time, the refrigerant in the high-temperature-stage refrigeration system 210 flows along the following paths: high temperature stage compressor 211- & gthigh temperature stage condenser 212- & gthigh temperature stage dew point prevention tube 213- & gthigh temperature stage dry filter- & gtfirst control valve 2151- & gthigh temperature stage depressurization member 2162- & gtsecond control valve 2152- & gthigh temperature stage heat exchange member 218- & gtthird control valve 2153- & gtrefrigeration evaporator 2171- & gtsecond control valve 2152- & gthigh temperature stage liquid storage package 219- & gthigh temperature stage muffler 220- & gthigh temperature stage compressor 211.

As will be appreciated by those skilled in the art, in the first cooling mode, the refrigerant flows through the high-temperature-stage heat exchange member 218 and then through the freezing evaporator 2172, but not through the refrigerating evaporator 2171, so that the cascade refrigeration system 200 can preferentially cool the low-temperature-stage storage compartment 112 and then cool the refrigerating storage compartment 1111 when simultaneously cooling the refrigerating storage compartment 1111 and the low-temperature-stage storage compartment 112, thereby improving the refrigeration efficiency of the refrigeration apparatus 1000.

As shown in fig. 5, when the refrigeration system is operating in the second refrigeration mode, the first control valve 2151 places the high temperature stage condenser 212 in communication with the high temperature stage pressure reducing member 2162 and places the high temperature stage condenser 212 out of communication with the refrigerated pressure reducing member 2161, the auxiliary pressure reducing member 2163. The second control valve 2152 communicates the outlet of the high temperature stage pressure reducing member 2162 with the inlet of the high temperature stage heat exchange member 218, and the outlet of the high temperature stage pressure reducing member 2162 is not communicated with the suction inlet of the high temperature stage compressor 211. The third control valve 2153 communicates the outlet of the high temperature stage heat exchange member 218 with the suction inlet of the high temperature stage compressor 211 and the outlet of the high temperature stage heat exchange member 218 is not in communication with the inlet of the freeze evaporator 2172, the inlet of the refrigeration evaporator 2171. At this time, the refrigerant in the high-temperature-stage refrigeration system 210 flows along the following paths: high temperature stage compressor 211- & gthigh temperature stage condenser 212- & gthigh temperature stage dew point prevention pipe 213- & gthigh temperature stage dry filter- & gtfirst control valve 2151- & gthigh temperature stage depressurization member 2162- & gtsecond control valve 2152- & gthigh temperature stage heat exchange member 218- & gtthird control valve 2153- & gthigh temperature stage liquid storage package 219- & gthigh temperature stage return pipe 220- & gthigh temperature stage compressor 211.

As will be appreciated by those skilled in the art, in the second cooling mode, the refrigerant only flows through the high-temperature heat exchange member 218, but not through the high-temperature evaporator 217, so that the cascade refrigeration system 200 can preferentially provide cold to the low-temperature storage compartment 112 when performing the low-temperature cycle, thereby improving the refrigeration efficiency of the refrigeration apparatus 1000.

As shown in fig. 6, when the refrigeration system is operating in the third refrigeration mode, the first control valve 2151 places the high temperature stage condenser 212 in communication with the high temperature stage pressure reducing member 2162 and places the high temperature stage condenser 212 out of communication with the refrigerated pressure reducing member 2161, the auxiliary pressure reducing member 2163. The second control valve 2152 communicates the outlet of the high temperature stage pressure reducing member 2162 with the inlet of the high temperature stage heat exchange member 218, and the outlet of the high temperature stage pressure reducing member 2162 is not communicated with the suction inlet of the high temperature stage compressor 211. The third control valve 2153 communicates the outlet of the high temperature stage heat exchange member 218 with the inlet of the freeze evaporator 2172 and the outlet of the high temperature stage heat exchange member 218 is not in communication with the inlet of the refrigeration evaporator 2171, the suction inlet of the high temperature stage compressor 211. At this time, the refrigerant in the high-temperature-stage refrigeration system 210 flows along the following paths: high temperature stage compressor 211- & gthigh temperature stage condenser 212- & gthigh temperature stage dew point prevention tube 213- & gthigh temperature stage dry filter- & gtfirst control valve 2151- & gthigh temperature stage depressurization member 2162- & gtsecond control valve 2152- & gthigh temperature stage heat exchange member 218- & gtthird control valve 2153- & gtfreeze evaporator 2172- & gthigh temperature stage liquid storage bag 219- & gthigh temperature stage air return tube 220- & gthigh temperature stage compressor 211.

As will be appreciated by those skilled in the art, in the third refrigeration mode, the refrigerant flows through the high-temperature heat exchange member 218 and then flows through the refrigeration evaporator 2172, instead of through the refrigeration evaporator 2171, so that the cascade refrigeration system 200 can preferentially provide the refrigeration capacity to the low-temperature storage compartment 112 and then to the refrigeration storage compartment 1112 when simultaneously refrigerating the refrigeration storage compartment 1112 and the low-temperature storage compartment 112, thereby improving the refrigeration efficiency of the refrigeration apparatus 1000.

Further, in other embodiments of the present utility model, at least one of the refrigerated pressure reducing member 2161, the high-temperature-stage pressure reducing member 2162, the auxiliary pressure reducing member 2163, and the low-temperature-stage pressure reducing member 236 is a capillary tube.

Further, one skilled in the art may also provide any one or more of the cold storage pressure reducing member 2161, the high-temperature-stage pressure reducing member 2162, the auxiliary pressure reducing member 2163, and the low-temperature-stage pressure reducing member 236 as an electronic expansion valve, as desired.

In other embodiments of the present utility model, the cascade refrigeration system 200 is used for a refrigeration appliance 1000, and the refrigeration appliance 1000 may be a refrigerator.

Based on the foregoing, one skilled in the art will appreciate that the present utility model is configured by providing the high temperature stage refrigeration system 210 of the cascade refrigeration system 200 to include the high temperature stage compressor 211, the high temperature stage condenser 212, the first control valve 2151, the refrigerated pressure reducing member 2161, the refrigerated evaporator 2171, the second control valve 2152, the high temperature stage heat exchange member 218, and the third control valve 2153 in series and forming a closed loop, including the high temperature stage pressure reducing member 2162 in series between the first control valve 2151 and the second control valve 2152 such that an outlet of the third control valve 2153 is fluidly connected to an inlet of the refrigerated evaporator 2171 to enable refrigerant in the system to flow along the following paths: high temperature stage compressor 211→high temperature stage condenser 212→first control valve 2151→high temperature stage pressure reducing member 2162→second control valve 2152→high temperature stage heat exchange member 218→third control valve 2153→refrigeration evaporator 2171→second control valve 2152→high temperature stage compressor 211. Meanwhile, the low-temperature-stage refrigeration system 230 in the cascade refrigeration system 200 is configured as a low-temperature-stage compressor 231, a low-temperature-stage condenser 232, a first heat exchange member 233, a low-temperature-stage heat exchange member 234, a low-temperature-stage dry filter 235, a low-temperature-stage depressurization member 236, a low-temperature-stage evaporator 237, a low-temperature-stage liquid storage bag 238, and a low-temperature-stage air return pipe 239, which are sequentially connected in series and form a closed loop. And the high-temperature stage heat exchange member 218 is thermally connected to the low-temperature stage heat exchange member 234 such that the refrigerant can flow through the high-temperature stage heat exchange member 218 before flowing through the refrigerating evaporator 2171, but not through the freezing evaporator 2172, so that the cascade refrigeration system 200 can preferentially refrigerate the low-temperature stage storage compartment 112 and refrigerate the refrigerating storage compartment 1111 after simultaneously refrigerating the refrigerating storage compartment 1111. Therefore, the present utility model overcomes the problem that the existing refrigeration equipment 1000 with the cascade refrigeration system 200 cannot preferentially refrigerate the very low temperature storage compartments with relatively low temperature when simultaneously refrigerates the plurality of storage compartments 110, and improves the refrigeration efficiency of the refrigeration equipment 1000.

Further, the present utility model allows refrigerant in the high temperature stage refrigeration system 210 to flow along the following paths by placing the outlet of the second control valve 2152 in fluid communication with the inlet of the high temperature stage heat exchange member 218 and the outlet of the third control valve 2153 in fluid communication with the suction of the high temperature stage compressor 211: high temperature stage compressor 211→high temperature stage condenser 212→first control valve 2151→high temperature stage pressure reducing member 2162→second control valve 2152→high temperature stage heat exchange member 218→third control valve 2153→high temperature stage compressor 211. The refrigerant only flows through the high-temperature-stage heat exchange member 218 and does not flow through the high-temperature-stage evaporator 217, so that the cascade refrigeration system 200 can preferentially provide cold energy to the extremely low-temperature storage compartment when in low-temperature circulation, and the refrigeration efficiency of the refrigeration equipment 1000 is further improved.

Further, the present utility model allows the refrigerant in the high temperature stage refrigeration system 210 to flow along the following paths by communicating the outlet of the second control valve 2152 with the inlet of the high temperature stage heat exchange member 218, the suction inlet of the high temperature stage compressor 211, and the outlet of the third control valve 2153 with the inlet of the refrigeration evaporator 2171, respectively: high temperature stage compressor 211→high temperature stage condenser 212→first control valve 2151→high temperature stage pressure reducing member 2162→second control valve 2152→high temperature stage heat exchange member 218→third control valve 2153→refrigeration evaporator 2171→second control valve 2152→high temperature stage compressor 211. The refrigerant flows through the high-temperature heat exchange member 218 and then flows through the refrigeration evaporator 2172, but does not flow through the refrigeration evaporator 2171, so that the cascade refrigeration system 200 can preferentially refrigerate the very low-temperature storage compartment and then refrigerate the refrigeration storage compartment 1111 when simultaneously refrigerating the refrigeration storage compartment 1112 and the low-temperature storage compartment 112, thereby further improving the refrigeration efficiency of the refrigeration device 1000.

Thus far, the technical solution of the present utility model has been described in connection with the foregoing embodiments, but it will be readily understood by those skilled in the art that the scope of the present utility model is not limited to only these specific embodiments. The technical solutions in the above embodiments can be split and combined by those skilled in the art without departing from the technical principles of the present utility model, and equivalent changes or substitutions can be made to related technical features, so any changes, equivalent substitutions, improvements, etc. made within the technical principles and/or technical concepts of the present utility model will fall within the protection scope of the present utility model.

Claims (10)

1. The cascade refrigeration system is characterized by comprising a high-temperature-level refrigeration system and a low-temperature-level refrigeration system, wherein the high-temperature-level refrigeration system is used for refrigerating the low-temperature-level refrigeration system;

the high-temperature-stage refrigeration system comprises a high-temperature-stage compressor, a high-temperature-stage condenser, a first control valve, a refrigerating depressurization member, a refrigerating evaporator, a second control valve, a high-temperature-stage heat exchange member and a third control valve which are sequentially connected in series and form a closed loop, and further comprises a high-temperature-stage depressurization member connected in series between the first control valve and the second control valve;

the low-temperature-stage refrigerating system comprises a low-temperature-stage compressor, a low-temperature-stage condenser, a low-temperature-stage depressurization member and a low-temperature-stage evaporator which are sequentially connected in series and form a closed loop, and further comprises a low-temperature-stage heat exchange member connected in series between an outlet of the low-temperature-stage compressor and an inlet of the low-temperature-stage depressurization member; the low-temperature-stage heat exchange member is thermally connected with the high-temperature-stage heat exchange member so that the high-temperature-stage heat exchange member absorbs heat of the low-temperature-stage heat exchange member.

2. The cascade refrigeration system of claim 1, wherein,

the high temperature stage refrigeration system further comprises a refrigeration evaporator connected in series between the outlet of the third control valve and the inlet of the high temperature stage compressor;

the high temperature stage pressure reducing member is fluidly connected by its outlet to the inlet of the freeze evaporator.

3. The cascade refrigeration system of claim 2, wherein,

the high temperature stage refrigeration system further comprises an auxiliary depressurization member and an auxiliary evaporator sequentially connected in series between the first control valve and the third control valve.

4. The cascade refrigeration system as recited in claim 3, wherein,

the first control valve is a four-way reversing valve with one inlet and three outlets, the first control valve is in fluid connection with the outlet of the high-temperature-stage condenser through the inlet of the first control valve, and the first control valve is in fluid connection with the inlet of the high-temperature-stage depressurization member, the inlet of the refrigeration depressurization member and the inlet of the auxiliary depressurization member through the three outlets of the first control valve; and/or the number of the groups of groups,

the second control valve is a four-way reversing valve with two inlets and two outlets, the second control valve is respectively in fluid connection with the outlet of the refrigeration evaporator and the outlet of the high-temperature-stage depressurization member through the two inlets of the second control valve, and the second control valve is respectively in fluid connection with the inlet of the high-temperature-stage heat exchange member and the inlet of the high-temperature-stage compressor through the two outlets of the second control valve; and/or the number of the groups of groups,

the third control valve is a four-way reversing valve with one inlet and three outlets, the third control valve is in fluid connection with the outlet of the high-temperature-stage heat exchange component through the inlet of the third control valve, and the third control valve is in fluid connection with the inlet of the refrigeration evaporator, the inlet of the freezing evaporator and the inlet of the high-temperature-stage compressor through the three outlets of the third control valve.

5. The cascade refrigeration system as recited in claim 3, wherein,

at least one of the refrigerating step-down member, the high-temperature-stage step-down member, the auxiliary step-down member, and the low-temperature-stage step-down member is a capillary tube.

6. The cascade refrigeration system as recited in any one of claims 1-5, wherein,

the cascade refrigeration system is used for refrigeration equipment.

7. A refrigeration apparatus comprising a cabinet and the cascade refrigeration system of claim 1, the cabinet defining a high temperature-stage storage compartment, a high temperature-stage refrigeration compartment, a low temperature-stage storage compartment, and a low temperature-stage refrigeration compartment therein;

the high temperature stage storage compartments include a refrigerated storage compartment;

the high-temperature-stage refrigeration compartment comprises a refrigeration compartment communicated with the refrigeration storage compartment,

the refrigerated evaporator is disposed within the refrigerated compartment.

8. A refrigeration device according to claim 7, wherein,

the high temperature grade compartment further comprises a freezer compartment,

the high temperature stage refrigeration compartment further comprises a refrigeration compartment in communication with the refrigeration storage compartment,

the high temperature stage refrigeration system further includes a refrigeration evaporator in series between an outlet of the third control valve and an inlet of the high temperature stage compressor, the refrigeration evaporator being disposed within the refrigeration compartment.

9. A refrigeration device according to claim 7, wherein,

the high-temperature-stage refrigeration system further comprises an auxiliary depressurization member and an auxiliary evaporator which are sequentially connected in series between the first control valve and the third control valve,

the auxiliary evaporator is disposed within the low-temperature-stage refrigeration compartment.

10. A refrigeration appliance according to any one of claims 7 to 9 wherein,

the refrigeration appliance is a refrigerator.