CN113701429A

CN113701429A - Refrigerator and control method thereof

Info

Publication number: CN113701429A
Application number: CN202010444066.5A
Authority: CN
Inventors: 宋向鹏; 刘山山; 戚斐斐; 刘建如
Original assignee: Qingdao Haier Refrigerator Co Ltd; Haier Smart Home Co Ltd
Current assignee: Qingdao Haier Refrigerator Co Ltd; Haier Smart Home Co Ltd
Priority date: 2020-05-22
Filing date: 2020-05-22
Publication date: 2021-11-26
Also published as: WO2021218343A1

Abstract

The invention provides a refrigerator and a control method thereof. The refrigerator comprises a refrigerator body, a high-temperature refrigeration circulation loop and a low-temperature refrigeration circulation loop, wherein a first storage compartment is formed in the refrigerator body; the high-temperature refrigeration circulation loop comprises a first evaporator and an evaporation part, wherein the first evaporator is used for absorbing heat and supplying cold for the first storage compartment; the low-temperature-level refrigeration cycle loop comprises a condensation part and a second evaporator used for absorbing heat, the condensation part is thermally connected with the evaporation part, and the second evaporator supplies cold for the first storage compartment in a direct cooling mode. Make the single storing compartment of refrigerator have the multi-temperature-zone function, even first storing compartment can obtain different refrigeration effect to satisfy different refrigeration demand and storing demand, the second evaporimeter is first storing compartment cooling through direct cold mode, can prevent that the second evaporimeter from frosting very fast, when preventing to need frequently change the frost, the room temperature fluctuation is less, guarantees food fresh-keeping effect.

Description

Refrigerator and control method thereof

Technical Field

The invention relates to the field of refrigeration, in particular to a refrigerator and a control method thereof.

Background

At present, the temperature range of the temperature-changing chamber of the refrigerator on the market is mostly adjusted between 8 ℃ and 18 ℃, and the overall design is more conventional. With the gradual improvement of living standard of people, the refrigerator with the temperature zone can not well meet the requirements of people, a high-end refrigerator which has a wider temperature range and more complete functions and can meet more requirements of users needs to be designed, the food is stored at a glass state below-40 ℃, the food nutritive value can be stored to the maximum extent, the market of the high-end user has the requirement on an ultralow temperature compartment (minus 40 ℃ to minus 60 ℃), and the user experience is grasped tightly for improving the satisfaction degree of the user. For this reason, the conventional cascade compression refrigeration system is generally composed of two separate refrigeration cycles, which are called a high-temperature stage refrigeration cycle (referred to as a high-temperature portion) and a low-temperature stage refrigeration cycle (referred to as a low-temperature portion), respectively. The high temperature portion uses a first refrigerant having a relatively high evaporation temperature, and the low temperature portion uses a second refrigerant having a relatively low evaporation temperature. And a condensing evaporator is adopted, which utilizes the cold energy produced by the first refrigerant in the high-temperature part to condense the second refrigerant vapor discharged by the compressor in the low-temperature part, thereby realizing the low temperature below minus 60 ℃. However, in the partial overlapping type compression refrigeration system in the prior art, the high-temperature stage refrigeration cycle loop is only used for supplying cold to the condenser of the low-temperature stage refrigeration cycle loop, so that the refrigeration efficiency of the overlapping type compression refrigeration system is low, and the conventional deep cooling refrigerator only has a single temperature function, so that the system efficiency is low.

Disclosure of Invention

In order to overcome at least one technical defect of the existing cryogenic refrigerator, the inventor of the invention provides a cryogenic operation of a storage chamber by using an air-cooled evaporator, however, the inventor finds that if a low-temperature system is arranged as the air-cooled evaporator, the temperature of the storage chamber is lower, the evaporator frosts quickly, the surface temperature of the evaporator needs to be heated to be higher than 0 ℃ during defrosting, the temperature of the storage chamber is higher, and the food fresh-keeping effect cannot be ensured. Based on this, the invention provides a novel refrigerator and a control method thereof.

In one aspect, the invention provides a refrigerator, which comprises a refrigerator body, a high-temperature refrigeration cycle loop and a low-temperature refrigeration cycle loop, wherein a first storage compartment is formed in the refrigerator body;

the high-temperature refrigeration cycle loop comprises a first evaporator and an evaporation part, wherein the first evaporator is used for absorbing heat and supplying cold to the first storage compartment;

the low-temperature-level refrigeration cycle loop comprises a condensation part and a second evaporator used for absorbing heat, the condensation part is thermally connected with the evaporation part, and the second evaporator supplies cold to the first storage compartment in a direct cooling mode.

Optionally, the box body comprises an inner container, and the first storage compartment is arranged in the inner container; the second evaporator is arranged on the outer wall of the inner container.

Optionally, the second evaporator comprises an evaporation tube wound around two side walls, a top wall and a bottom wall of the inner container; or the like, or, alternatively,

the second evaporator is a tube-plate evaporator and is arranged on the two side walls, the top wall and the bottom wall of the inner container.

Optionally, the high-temperature stage refrigeration cycle circuit further comprises a control valve having a first outlet and a second outlet, the inlet of the evaporation part being in communication with the first outlet; the inlet of the first evaporator is communicated with the second outlet; the outlet of the first evaporator is communicated with the inlet of the evaporation part.

Optionally, a second storage compartment is formed inside the box body; the high-temperature-stage refrigeration cycle further comprises a third evaporator;

the third evaporator is used for supplying cold to the second storage compartment; and the inlet of the third evaporator is communicated with the outlet of the evaporation part.

Optionally, a third storage compartment is formed inside the box body; the high-temperature-stage refrigeration cycle loop further comprises a fourth evaporator, the fourth evaporator is used for supplying cold to the third storage compartment, and the fourth evaporator is arranged between the inlet of the evaporation part and the first outlet;

the control valve has a third outlet in communication with the inlet of the third evaporator;

a first throttling device is arranged between the inlet of the fourth evaporator and the first outlet;

a second throttling device is arranged between the inlet of the first evaporator and the second outlet;

a third throttling device is arranged between the inlet of the third evaporator and the third outlet;

the first storage compartment and the second storage compartment are arranged in parallel along the transverse extension direction of the refrigerator, and the third storage compartment is arranged on the upper sides of the first storage compartment and the second storage compartment;

and a valve which only allows the refrigerant from the second evaporator to flow out in one direction is arranged on the outlet pipe of the first evaporator.

Optionally, the refrigerator further comprises an air supply device, so that the first evaporator supplies cold to the first storage compartment in an air cooling mode, and the air supply device is turned on when the refrigerator is in a deep cooling mode in which the second evaporator works;

the refrigerator body is provided with a first evaporator and a first refrigerating chamber, the first evaporator is arranged in the position corresponding to the rear side of the first storage chamber, the first refrigerating chamber is communicated with the first storage chamber through a first air supply structure, and refrigerating airflow is provided for the first storage chamber through the first air supply structure.

Optionally, a second refrigeration chamber for arranging the third evaporator is further formed in the box body at a position corresponding to the rear side of the second storage compartment, and the second refrigeration chamber is communicated with the second storage compartment through a second air supply structure so as to provide refrigeration air flow to the second storage compartment through the second air supply structure;

the evaporation part and the condensation part are arranged in the second refrigerating chamber.

On the other hand, the invention also provides a control method of the refrigerator, the refrigerator comprises a refrigerator body, a high-temperature refrigeration cycle loop and a low-temperature refrigeration cycle loop, a first storage compartment is formed in the refrigerator body, the high-temperature refrigeration cycle loop comprises a first evaporator and an evaporation part, the first evaporator is used for absorbing heat, and the first evaporator supplies cold to the first storage compartment in an air cooling mode; the low-temperature-stage refrigeration cycle loop comprises a condensation part and a second evaporator used for absorbing heat, the condensation part is thermally connected with the evaporation part, and the second evaporator supplies cold to the first storage compartment in a direct cooling mode, wherein the control method comprises the following steps:

when the refrigerator is in a deep cooling mode in which the second evaporator works, detecting the frosting amount in the first storage room;

and when the frosting amount reaches a preset frosting amount, enabling the refrigerator to be in a normal refrigeration mode in which the first evaporator works.

Optionally, the refrigerator still includes air supply arrangement, so that first evaporimeter is through the forced air cooling mode for the cooling of first storing compartment, and is in the refrigerator is in when the cryrogenic mode of second evaporimeter work, opens air supply arrangement.

According to the refrigerator and the control method thereof, the high-temperature refrigeration circulation loop comprises the first evaporator, the low-temperature refrigeration circulation loop comprises the second evaporator, the first evaporator and the second evaporator can supply cold to the first storage chamber, so that a single storage chamber of the refrigerator has a multi-temperature-zone function, even if the first storage chamber can obtain different refrigeration effects to meet different refrigeration requirements and storage requirements, the temperature zone range of the first storage chamber can be expanded, namely, the refrigerator can have a deep cooling function and can meet energy-saving requirements of daily refrigeration. Particularly, the second evaporator supplies cold for the first storage compartment through the direct cooling mode, can prevent that the second evaporator from frosting sooner, when preventing to need frequent defrosting, the fluctuation of compartment temperature is less, guarantees the fresh-keeping effect of food.

Furthermore, in the refrigerator and the control method thereof, the first evaporator and the second evaporator are separately arranged, so that the temperature of the two evaporators can be prevented from being influenced with each other, the size of the evaporators can be prevented from being larger, the evaporators can be prevented from occupying larger space, and the storage space can be reduced.

Further, according to the refrigerator and the control method thereof, when the first evaporator works, namely in a normal refrigeration mode, the refrigerator is an air-cooled product, and the hidden danger of frosting is avoided. When the user switches into the cryrogenic mode of second evaporimeter work, the work of second evaporimeter direct cooling, with the fan cooperation that first evaporimeter during operation was used, both can rapid cooling, but also even refrigeration, the refrigerator can be run for a long time, and frosting is less. When the deep cooling mode is operated for a long time to cause the compartment to be frosted and too much frozen, the user can be switched to the normal cooling mode, and the first evaporator cooled by normal air is used for refrigerating and defrosting. Can maintain low temperature cryrogenic operation for a long time, guarantee to eat material long-time storage, if the defrosting needs simultaneously, the air-cooling system of accessible first evaporimeter gets rid of the residual frost layer of compartment, improves product result of use and user experience greatly.

Furthermore, the arrangement positions of each evaporator and the evaporation part in the high-temperature refrigeration circulation loop can ensure the refrigeration efficiency of each evaporator during normal refrigeration, improve the energy efficiency of the refrigerator and have obvious energy-saving effect. That is to say, the refrigerator can ensure that the temperature of each room is controlled when the high-temperature refrigeration circulation loop operates independently, the aim of saving energy is achieved, and the deep cooling function of the refrigerator can be realized by utilizing the low-temperature refrigeration circulation loop. The second evaporator is wound on two side walls, the top wall and the bottom wall of the inner container, and the direct cooling efficiency is obviously improved.

The above and other objects, advantages and features of the present invention will become more apparent to those skilled in the art from the following detailed description of specific embodiments thereof, taken in conjunction with the accompanying drawings.

Drawings

Some specific embodiments of the invention will be described in detail hereinafter, by way of illustration and not limitation, with reference to the accompanying drawings. The same reference numbers in the drawings identify the same or similar elements or components. Those skilled in the art will appreciate that the drawings are not necessarily drawn to scale. In the drawings:

fig. 1 is a schematic view of a refrigerator according to one embodiment of the present invention;

FIG. 2 is a schematic diagram of a refrigeration system in a refrigerator according to one embodiment of the present invention;

FIG. 3 is a schematic diagram of a refrigeration system in a refrigerator according to one embodiment of the present invention;

fig. 4 is a partial structural schematic view of a refrigerator according to an embodiment of the present invention;

fig. 5 is a partial structural cut-away schematic view of a refrigerator according to an embodiment of the present invention;

fig. 6 is a partial structural view of a refrigerator according to one embodiment of the present invention.

Detailed Description

Fig. 1 is a schematic view of a refrigerator according to one embodiment of the present invention. As shown in fig. 1, and referring to fig. 2 to 6, an embodiment of the present invention provides a refrigerator, which may include a cabinet 20 and a refrigeration system. One or more storage compartments are formed in the box body 20, and in some embodiments, the storage compartments may include a first storage compartment 21. In some embodiments, the storage compartments may include a first storage compartment 21, a second storage compartment 22, and a third storage compartment 23. A refrigeration system, which may also be referred to as a cascade compression refrigeration system, may be disposed within the cabinet 20 and include a high temperature stage refrigeration cycle 30 and a low temperature stage refrigeration cycle 40.

As shown in fig. 2 and 3, the high-temperature stage refrigeration cycle circuit 30 is for circulating a first refrigerant, and is provided therein with a first evaporator 36 and an evaporation portion 37 for absorbing heat. The first evaporator 36 serves to promote the first refrigerant flowing therethrough to absorb heat and to supply cold to the first storage compartment 21. The high temperature stage refrigeration cycle loop 30 also includes a high temperature stage compressor 31 and a high temperature stage condensing unit 32. The low-temperature-stage refrigeration cycle circuit 40 is for circulating the second refrigerant, and is provided therein with a condensation portion 42 and a second evaporator 44. The second evaporator 44 is used for promoting the second refrigerant flowing through the second evaporator to absorb heat and supplying cold to the first storage compartment 21. The low-temperature stage refrigeration cycle circuit 40 also includes a low-temperature stage compressor 41. The evaporation portion 37 functions to cause the first refrigerant flowing therethrough to absorb heat of the second refrigerant flowing through the condensation portion 42 in the low-temperature-stage refrigeration cycle circuit 40. The first refrigerant and the second refrigerant may be the same refrigerant, such as R600a, or different refrigerants.

The refrigerant, also called refrigerant, usually completes energy conversion by phase change, is a working substance that circulates in a refrigeration system of a refrigeration device, and its working principle is: the refrigerant absorbs heat of a substance to be cooled in the evaporator to evaporate, transfers the absorbed heat to ambient air or water in the condenser to be cooled into liquid, and circulates back and forth to achieve the refrigeration effect by means of state change. The "high temperature" and the "low temperature" in the "high temperature stage refrigeration cycle circuit 30" and the "low temperature stage refrigeration cycle circuit 40" are relative, and the evaporation temperature of the first refrigerant flowing through the high temperature stage refrigeration cycle circuit 30 is higher than the evaporation temperature of the second refrigerant flowing through the low temperature stage refrigeration cycle circuit 40.

In the refrigerator according to the embodiment of the present invention, the first evaporator 36 is disposed in the high-temperature stage refrigeration cycle 30. The first evaporator 36 is used for cooling the first storage compartment 21, and the second evaporator 44 is arranged in the low-temperature stage refrigeration cycle loop 40 and used for cooling the first storage compartment 21. The energy utilization efficiency in the high-temperature refrigeration cycle circuit 30 is improved, and the refrigeration efficiency of the refrigerator is improved. The first evaporator 36 and the second evaporator 44 can both supply cold to the first storage compartment 21, so that a single storage compartment of the refrigerator has a multi-temperature-zone function, even if the first storage compartment 21 can obtain different refrigeration effects to meet different refrigeration requirements, the temperature zone range of the first storage compartment 21 can be enlarged, that is, the refrigerator can have a deep cooling function and can meet energy-saving requirements of daily refrigeration. For example, the temperature of the first storage compartment 21 may be brought to-18 ℃ by the first evaporator 36 and the temperature of the first storage compartment 21 may be brought to-60 ℃ by the second evaporator 44.

Preferably, as shown in fig. 4 and 5, in the present embodiment, the second evaporator 44 supplies the first storage compartment 21 with cold by direct cooling. For example, the box 20 includes an inner container, and the inner container has a first storage compartment 21 therein; the second evaporator 44 is provided on the outer wall of the inner container. Specifically, the second evaporator 44 includes an evaporation tube wound around two side walls, a top wall and a bottom wall of the inner container, and may be wound in a spiral manner or other winding manners. Alternatively, the second evaporator 44 is a tube-plate evaporator, and is disposed on two side walls, walls and a bottom wall of the inner container.

Second evaporimeter 44 is first storing compartment 21 cooling through direct cooling mode, can prevent that second evaporimeter 44 from frosting very fast, when preventing to need frequent defrosting, and the temperature fluctuation of compartment is less, guarantees the fresh-keeping effect of food. The low-temperature deep cooling operation can be maintained for a long time, the long-time storage of food materials is guaranteed, and the using effect of products and the user experience are greatly improved. First evaporator 36 and second evaporator 44 separately set up, can prevent that two evaporimeter temperatures from influencing each other, also can prevent that the evaporimeter size is great, occupy great space for the storing space diminishes. The second evaporator 44 is wound around two side walls, a top wall and a bottom wall of the inner container, and the direct cooling efficiency is remarkably improved.

In some embodiments of the present invention, the high temperature stage refrigeration cycle loop 30 further includes a control valve 33. The inlet of the control valve 33 may be in communication with the inlet of the high temperature stage condensing unit 32. The control valve 33 has a first outlet and a second outlet, the inlet of the first evaporator 36 communicating with the second outlet; the inlet of the evaporation portion 37 communicates with the first outlet. The outlet of the first evaporator 36 communicates with the inlet of the evaporation portion 37. The control valve 33 may be a switching valve.

In some embodiments of the present invention, as shown in fig. 2 and 3, the high temperature stage refrigeration cycle further includes a third evaporator 35. The third evaporator 35 is used for cooling the second storage compartment 22; the inlet of the third evaporator 35 communicates with the outlet of the evaporation portion 37. In some embodiments of the present invention, as shown in fig. 3, the high-temperature stage refrigeration cycle further includes a fourth evaporator 38, the fourth evaporator 38 is used for cooling the third storage compartment 23, and the fourth evaporator 38 is disposed between the inlet and the first outlet of the evaporation portion 37. The arrangement positions of each evaporator and the evaporation part 37 in the high-temperature refrigeration circulation loop can ensure the refrigeration efficiency of each evaporator during conventional refrigeration, improve the energy efficiency of the refrigerator and have obvious energy-saving effect. That is, the refrigerator can ensure temperature control of each compartment when the high-temperature refrigeration cycle circuit 30 operates alone, achieve the purpose of energy saving, and can realize the deep cooling function of the refrigerator by using the low-temperature refrigeration cycle circuit 40.

In some embodiments of the invention, the control valve 33 has a third outlet. The third outlet communicates with the inlet of the third evaporator 35. A first throttling device 343 is arranged between the inlet and the first outlet of the fourth evaporator 38; a second throttling device 342 is arranged between the inlet and the second outlet of the first evaporator 36; a third throttling device 341 is disposed between the inlet and the third outlet of the third evaporator 35. In alternative embodiments, a total restriction may be provided at the inlet of the control valve 33. Further, the first throttling means 343, the second throttling means 342 and the third throttling means 341 may each be a capillary tube. Alternatively, the first throttling device 343, the second throttling device 342 and the third throttling device 341 may be electromagnetic expansion valves. The control valve 33 may now be selected as a one-in-many flow divider valve.

In some embodiments of the present invention, as shown in fig. 1, the first storage compartment 21 and the second storage compartment 22 are disposed in parallel in a lateral extension direction of the refrigerator, and the third storage compartment 23 is disposed at an upper side of the first storage compartment 21 and the first storage compartment 21. The second storage compartment 22 may be a freezing compartment, the first storage compartment 21 may be a multifunctional compartment having multiple temperature zones, and the third storage compartment 23 may be a refrigerating compartment. The arrangement can ensure that the compartment layout is more reasonable and the corresponding articles can be more conveniently stored and taken.

In some embodiments of the present invention, as shown in fig. 4 and 5, the refrigerator further includes an air supply device 50, so that the first evaporator 36 supplies cold to the first storage compartment 21 through an air cooling manner, that is, the air supply device 50 is used for promoting an air flow to flow through the first evaporator 36 and to enter the first storage compartment 21. Preferably, the air blowing device 50 is turned on when the refrigerator is in the deep cooling mode in which the second evaporator 44 is operated.

In the present embodiment, when the first evaporator 36 is in operation, i.e. in the normal cooling mode, the refrigerator is an air-cooled product, and there is no hidden danger of frosting. When the user switches to the deep cooling mode in which the second evaporator 44 operates, the second evaporator 44 operates in direct cooling, and cooperates with the fan 50 used when the first evaporator 36 operates, so that not only can the temperature be rapidly reduced, but also the refrigeration can be uniformly performed, and the refrigerator can operate for a long time with less frosting. When the deep cooling mode is operated for a long time to cause the compartment to be frosted and too much frozen, the user can switch to the normal cooling mode to refrigerate and defrost through the first evaporator 36 cooled by normal air. Can maintain low temperature cryrogenic operation for a long time, guarantee to eat material long-time storage, if the defrosting needs simultaneously, room residual frost layer is got rid of to the air-cooled system of accessible first evaporimeter 36, improves product result of use and user experience greatly.

Further, the cabinet 20 is further formed with a first refrigerating chamber 24 for arranging the first evaporator 36 at a position corresponding to the rear side of the first storage compartment 21, the first refrigerating chamber 24 is communicated with the first storage compartment 21 through the first air supply structure 51, and a refrigerating air flow is provided to the first storage compartment 21 through the first air supply structure 51.

In some embodiments of the present invention, as shown in fig. 1 and 6, the cabinet 20 is further formed with a second cooling compartment for disposing the third evaporator 35 at a position corresponding to the rear side of the second storage compartment 22, and the second cooling compartment is communicated with the second storage compartment 22 through the second air supply structure 52 to provide a flow of cooling air to the second storage compartment 22 through the second air supply structure 52. The box body 20 is further formed with a third refrigerating chamber for arranging a fourth evaporator 38 at a position corresponding to the rear side of the third storage compartment 23, and the third refrigerating chamber is communicated with the third storage compartment 23 through a third air supply structure so as to provide refrigerating air flow to the third storage compartment 23 through the third air supply structure.

The first air supply structure is arranged between the first refrigerating chamber 24 and the first storage compartment 21; an air inlet is arranged on the rear side surface of the first air supply structure 51, and the air supply device 50 is arranged at the air inlet. A plurality of air blowing ports 54 are provided on the front side surface of the first air blowing structure 51, and an air blowing duct 55 is provided in the first air blowing structure 51. The lower side of the first air supply structure can be provided with an air return duct 56, so that the evaporator can supply air from the bottom and discharge air from the upper part. The second air blowing structure and the third air blowing structure are similar to the first air blowing structure 51.

The outlet pipe of the first evaporator 36 is provided with a valve which allows only the refrigerant from the first evaporator 36 to flow out in one direction. The valve may be a check valve 39, the check valve 39 functioning to prevent reverse passage of the first refrigerant downstream of the check valve 39. When the low temperature stage compressor 41 is operated, the temperature of the second evaporator 44 is low. The low temperature in the first storage compartment 21 causes the first evaporator 36 to have a relatively low line temperature, even significantly lower than the temperature of the other evaporators located downstream of the first evaporator 36 in the high-temperature-stage refrigeration cycle 30. The valve can prevent the first refrigerant in other cooling evaporators positioned at the downstream of the first evaporator 36 from flowing into the first evaporator 36 from the discharge port of the first evaporator 36, so that the first refrigerant in the high-temperature-stage refrigeration cycle circuit 30 can be prevented from flowing reversely, the effective circulation amount of the first refrigerant is ensured, and the overall refrigeration efficiency is improved. The first refrigerant in the high-temperature-stage refrigeration cycle can be prevented from gradually accumulating in the first evaporator 36, and the refrigerant in the high-temperature-stage refrigeration cycle gradually decreases to cause poor refrigeration. The refrigerant is prevented from reversely flowing and accumulating in the first evaporator 36 by the check valve 39 to cause a poor cooling. The check valve 39 can solve the problem of refrigerant aggregation caused by low temperature without controlling the operation of the program regulating valve body, and has simple structure and strong operability.

The high temperature stage condensing unit 32 may include a condenser and a dew condensation preventing pipe. The low temperature stage refrigeration cycle circuit 40 further includes a low temperature stage condensing device 45 and a low temperature stage throttling device 43. The inlet of the high-temperature stage condensing device 32 is communicated with the outlet of the high-temperature stage compressor 31, and the outlet of the third evaporator 35 is communicated with the inlet of the high-temperature stage compressor 31. An outlet of the low-temperature stage compressor 41 is communicated with an inlet of a low-temperature stage condensing device 45, an outlet of the low-temperature stage condensing device 45 is communicated with an inlet of a condensing part 42, an outlet of the condensing part 42 is communicated with a low-temperature stage throttling device 43, an outlet of the low-temperature stage throttling device 43 is communicated with an inlet of a second evaporator 44, and an outlet of the second evaporator 44 is communicated with an inlet of the low-temperature stage compressor 41.

In some alternative embodiments, the condensing portion 42 and the evaporating portion 37 may form a condensing evaporator. The condensing evaporator can be a double-pipe heat exchanger, the double-pipe heat exchanger is a concentric sleeve formed by mutually sleeving and connecting two standard pipes with different sizes, the channel outside is called a shell pass, and the channel inside is called a pipe pass. The two different media can flow in the shell side and the tube side in the opposite directions (or in the same direction) to achieve the effect of heat exchange. The evaporation section 37 may be a tube side and the condensation section 42 may be a shell side. In other alternative embodiments, the condensation section 42 and the evaporation section 37 can also be two copper tubes abutting each other. The two copper pipes are arranged in a mutual attaching mode. The contact part between the two copper pipes can be fixed by tin soldering to strengthen the heat transfer. The two copper pipes can be wrapped with aluminum foils. In other alternative embodiments, the condensing portion 42 and the evaporating portion 37 may share heat exchange fins. The evaporation unit 37 and the condensation unit 42 are provided in the second refrigeration chamber. Of course, the evaporation part 37 and the condensation part 42 may be provided at other positions of the refrigerator.

The embodiment of the invention also provides a control method of the refrigerator, the refrigerator comprises a refrigerator body 20, a high-temperature refrigeration cycle loop 30 and a low-temperature refrigeration cycle loop 40, the first storage compartment 21 is formed in the refrigerator body 20, and the high-temperature refrigeration cycle loop comprises a first evaporator 36 for absorbing heat and an evaporation part 37. The first evaporator 36 supplies cold to the first storage compartment 21 in an air cooling manner. The low-temperature-stage refrigeration cycle circuit 40 includes a condensation portion 42 and a second evaporator 44 for absorbing heat, the condensation portion 42 is thermally connected to the evaporation portion 37, and the second evaporator 44 supplies cold to the first storage compartment 21 by direct cooling. Specifically, the control method includes: the amount of frost formation in the first storage compartment 21 is detected while the refrigerator is in the deep cooling mode in which the second evaporator 44 is operated. When the amount of frost reaches the preset amount of frost, the refrigerator is put in a normal cooling mode in which the first evaporator 36 operates. Further, the control method of the refrigerator further includes turning on the blowing device 50 when the refrigerator is in the deep cooling mode in which the second evaporator 44 is operated.

In the control method of the refrigerator according to the embodiment of the present invention, when the first evaporator 36 operates, i.e., in the normal refrigeration mode, the refrigerator is an air-cooled product, and there is no hidden danger of frosting. When the user switches to the deep cooling mode in which the second evaporator 44 operates, the second evaporator 44 operates in direct cooling, and cooperates with the fan used when the first evaporator 36 operates, so that not only can the temperature be rapidly reduced, but also the refrigeration can be uniformly performed, the refrigerator can operate for a long time, and the frosting is less. When the deep cooling mode is operated for a long time to cause the compartment to be frosted and too much frozen, the user can switch to the normal cooling mode to refrigerate and defrost through the first evaporator 36 cooled by normal air. Can maintain low temperature cryrogenic operation for a long time, guarantee to eat material long-time storage, if the defrosting needs simultaneously, room residual frost layer is got rid of to the air-cooled system of accessible first evaporimeter 36, improves product result of use and user experience greatly.

Thus, it should be appreciated by those skilled in the art that while a number of exemplary embodiments of the invention have been illustrated and described in detail herein, many other variations or modifications consistent with the principles of the invention may be directly determined or derived from the disclosure of the present invention without departing from the spirit and scope of the invention. Accordingly, the scope of the invention should be understood and interpreted to cover all such other variations or modifications.

Claims

1. A refrigerator comprises a refrigerator body, wherein a first storage compartment is formed in the refrigerator body, and the refrigerator is characterized by further comprising a high-temperature refrigeration circulation loop and a low-temperature refrigeration circulation loop;

2. The refrigerator according to claim 1,

the box body comprises an inner container, and the first storage compartment is arranged in the inner container; the second evaporator is arranged on the outer wall of the inner container.

3. The refrigerator according to claim 2,

the second evaporator comprises evaporation tubes, and the evaporation tubes are wound on two side walls, a top wall and a bottom wall of the inner container; or the like, or, alternatively,

4. The refrigerator according to claim 1,

the high-temperature stage refrigeration cycle loop further comprises a control valve, the control valve is provided with a first outlet and a second outlet, and an inlet of the evaporation part is communicated with the first outlet; the inlet of the first evaporator is communicated with the second outlet; the outlet of the first evaporator is communicated with the inlet of the evaporation part.

5. The refrigerator according to claim 4,

a second storage chamber is formed in the box body; the high-temperature-stage refrigeration cycle further comprises a third evaporator;

6. The refrigerator according to claim 5,

a third storage chamber is formed in the box body; the high-temperature-stage refrigeration cycle loop further comprises a fourth evaporator, the fourth evaporator is used for supplying cold to the third storage compartment, and the fourth evaporator is arranged between the inlet of the evaporation part and the first outlet;

7. The refrigerator of claim 1, further comprising an air supply device to cool the first storage compartment by air cooling, wherein the air supply device is turned on when the refrigerator is in a deep cooling mode in which the second evaporator operates;

8. The refrigerator according to claim 5,

a second refrigerating chamber used for arranging the third evaporator is formed in the position, corresponding to the rear side of the second storage compartment, of the box body, and the second refrigerating chamber is communicated with the second storage compartment through a second air supply structure so as to provide refrigerating airflow for the second storage compartment through the second air supply structure;

9. The control method of the refrigerator is characterized in that the refrigerator comprises a refrigerator body, a high-temperature refrigeration cycle loop and a low-temperature refrigeration cycle loop, a first storage compartment is formed inside the refrigerator body, the high-temperature refrigeration cycle loop comprises a first evaporator and an evaporation part, the first evaporator is used for absorbing heat, and the first evaporator supplies cold to the first storage compartment in an air cooling mode; the low-temperature-stage refrigeration cycle loop comprises a condensation part and a second evaporator used for absorbing heat, the condensation part is thermally connected with the evaporation part, and the second evaporator supplies cold to the first storage compartment in a direct cooling mode, wherein the control method comprises the following steps:

10. The control method of a refrigerator according to claim 9,

the refrigerator also comprises an air supply device, so that the first evaporator is used for cooling the first storage compartment in an air cooling mode, and the air supply device is started when the refrigerator is in a deep cooling mode in which the second evaporator works.