JP2016200376A - refrigerator - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a refrigerator that can shorten the time for which the cooling of a refrigerating space is stopping.SOLUTION: A refrigerator includes a cooling cycle in which a compressor 41, a condenser 42 and a selector valve 43 are successively connected, an evaporator 52 for refrigerating is connected to a first outlet of the selector valve, an evaporator 62 for freezing is connected to a second outlet of the selector valve, and the evaporator for refrigerating and the evaporator for freezing are connected to the compressor, a defrosting device 65, and a control portion for controlling the cooling system and the defrosting device. The control portion implements a basic operation control for alternately operating the evaporator for refrigerating and the evaporator for freezing, so that the basic operation control is stopped and the defrost control is executed when a defrost start condition is satisfied, and in the defrost control, the evaporator for freezing is defrosted by the defrosting device after recovering a refrigerant in the evaporator for freezing with the compressor, and the evaporator for refrigerating is operated during the defrosting.SELECTED DRAWING: Figure 2

Description

  Embodiments of the present invention relate to a refrigerator.

  In a refrigerator, a compressor, a condenser, and an evaporator are connected in this order by piping or the like, and a loop in which the refrigerant circulates is formed. Some refrigerators have only one compressor and condenser, and two evaporators. One of the evaporators is for refrigeration cooling and the other is for refrigeration cooling. These evaporators are provided in parallel in the loop. When the refrigerated space is cooled (refrigerated cooling), the refrigerant flows toward the refrigerated cooling evaporator, and when the refrigerated space is cooled (refrigerated cooling), the refrigerant flows toward the refrigerated cooling evaporator. (See, for example, Patent Document 1).

  By the way, since the refrigerant is generally a flammable substance such as isobutane, so-called pump-down in which the refrigerant is extracted from the refrigeration / cooling evaporator is performed before defrosting to heat the refrigeration / cooling evaporator. Thereafter, defrosting of the refrigeration / cooling evaporator is performed, but if refrigeration cooling is performed during the defrosting, a large amount of refrigerant extracted by pump-down flows to the refrigeration / cooling evaporator. Then, the refrigerant cannot be completely evaporated by the refrigeration cooling evaporator, and the liquid refrigerant flows out of the refrigeration cooling evaporator and flows into the compressor, and the compressor may be broken. In order to prevent this, not only refrigeration cooling but also refrigeration cooling was not performed during defrosting after pump down.

JP 2011-257113 A

  As described above, conventionally, since refrigeration cooling is not performed during defrosting, there is a problem that the cooling time of the refrigeration space is long and the temperature of the refrigeration space easily rises.

  Therefore, an object of the present invention is to provide a refrigerator that can shorten the time during which cooling of the refrigerated space is stopped and can suppress an increase in temperature of the refrigerated space.

  In the refrigerator of the embodiment, a compressor, a condenser, and a switching valve are connected in this order, a refrigeration evaporator is connected to a first outlet of the switching valve, and a refrigeration evaporator is connected to a second outlet of the switching valve. A cooling cycle in which the refrigeration evaporator and the refrigeration evaporator are connected to the compressor, a defrosting device for defrosting the refrigeration evaporator, the cooling cycle and the defrosting device. A control unit that controls the refrigeration evaporator and the refrigeration evaporator, the control unit performs basic operation control alternately, and when the defrosting start condition is satisfied, After the operation of the refrigeration evaporator in the basic operation control, the basic operation control is temporarily stopped and the defrost control is executed. In the defrost control, the refrigerant in the refrigeration evaporator is compressed. For the freezing by the defroster Performs defrosting of Hatsuki, characterized by operating said refrigerating evaporator during the defrosting.

Sectional drawing of the front-back direction of the refrigerator 10 of embodiment. The figure which shows the cooling cycle 40 of embodiment. The block diagram of the refrigerator 10 of embodiment. The flowchart of the control for defrost of embodiment. The figure which shows another cooling cycle 140 of embodiment. The figure which shows the cooling cycle 240 of the example of a change.

  Embodiments will be described with reference to the drawings.

  As shown in FIG. 1, the refrigerator 10 according to the present embodiment includes a refrigerator main body 12 in which an outer box that forms an outer shell of the refrigerator 10 and an inner box that forms a storage space inside are combined. Between the outer box and the inner box, a foam heat insulating material or the like is filled. The storage space inside the inner box is partitioned into a refrigerated space 20 and a frozen space 30 by a heat insulating partition wall 14. For example, in the case of the refrigerator 10 of FIG. 1, it is partitioned so that the refrigerated space 20 is on the upper side and the refrigerated space 30 is on the lower side.

  The refrigeration space 20 is a space that is cooled to a refrigeration temperature (for example, 2 to 3 ° C.), and the inside thereof is further partitioned as necessary. For example, in the case of the refrigerator 10 of FIG. 1, the inside of the refrigeration space 20 is partitioned vertically by a partition plate, the upper part is a refrigeration room 22 provided with a plurality of stages of mounting shelves, and the lower part is a drawer-type storage container 24. It is an arranged vegetable room 26. A refrigerated space temperature sensor 29 that measures the temperature in the refrigerated space 20 is provided in the refrigerated space 20.

  The freezing space 30 is a space cooled to a freezing temperature (for example, −18 ° C. or lower), and the inside thereof is further partitioned as necessary. For example, in the case of the refrigerator 10 of FIG. 1, an ice making chamber 32 provided with an automatic ice maker is provided above, and a freezing chamber 34 is provided below. A frozen space temperature sensor 39 that measures the temperature in the frozen space 30 is provided in the frozen space 30.

  Front openings of storage rooms such as the refrigerator room 22, the vegetable room 26, the ice making room 32, and the freezing room 34 are closed by doors such as a kannon type and a drawer type.

  A cooling cycle 40 for cooling the refrigerated space 20 and the frozen space 30 is shown in FIG. In the cooling cycle 40, the compressor 41, the condenser 42, and the switching valve 43 are connected in this order. In the embodiment of FIG. 2, the switching valve 43 is a three-way valve, and has a refrigeration side outlet 50 as a first outlet and a refrigeration side outlet 60 as a second outlet.

  The refrigerating side outlet 50 includes a refrigerating capillary tube 51 as a throttling device, a refrigerating evaporator 52 that generates cold air for cooling the refrigerating space 20, and a refrigerating accumulator 53 as a gas-liquid separator. They are connected in this order. The refrigeration accumulator 53 can separate the liquid refrigerant and the gaseous refrigerant, and can store the liquid refrigerant therein. The refrigeration accumulator 53 is connected to the compressor 41. The refrigeration evaporator 52 is provided with a temperature sensor 56 for measuring the temperature.

  At the freezing side outlet 60, a freezing capillary tube 61 as a throttling device, a freezing evaporator 62 for generating cold air for cooling the freezing space 30, a freezing accumulator 63 as a gas-liquid separation device, The stop valve 64 is connected in this order. The refrigeration accumulator 63 can separate the liquid refrigerant and the gaseous refrigerant, and can store the liquid refrigerant therein. The check valve 64 is connected to the compressor 41. The refrigeration evaporator 62 is provided with a temperature sensor 66 for measuring the temperature.

  When the refrigerant flows through the cooling cycle 40 having the above configuration, cold air is generated in the refrigeration evaporator 52 and the refrigeration evaporator 62. Note that an expansion valve may be used as the throttle device instead of the capillary tube.

  The refrigeration evaporator 52 is provided in the back of the refrigeration space 20. A refrigeration fan 28 is provided in the vicinity of the refrigeration evaporator 52. When the refrigeration fan 28 rotates, cold air circulates in the entire refrigeration space 20 including the periphery of the refrigeration evaporator 52.

  The refrigeration evaporator 62 is provided in the back of the refrigeration space 30. A refrigeration fan 38 is provided in the vicinity of the refrigeration evaporator 62. When the refrigeration fan 38 rotates, cold air circulates throughout the refrigeration space 30 including the refrigeration evaporator 62. A defrosting heater 65 as a defrosting device is provided outside the freezing evaporator 62.

  The refrigerator 10 is provided with a microcomputer 70 as a control unit. As shown in FIG. 3, the microcomputer 70 includes a defrost heater 65, a refrigeration fan 28, a refrigeration fan 38, a compressor 41 of a cooling cycle 40, a switching valve 43, and other various sensors and devices as necessary. Is connected. The microcomputer 70 controls these connected items.

  When cooling the refrigerated space 20 (refrigerated cooling), the microcomputer 70 closes the refrigeration side outlet 60 of the switching valve 43 and opens the refrigeration side outlet 50, thereby causing the refrigerant to flow to the refrigeration evaporator 52, thereby causing the refrigeration evaporator. Drive 52. Further, the microcomputer 70 rotates the refrigeration fan 28. As a result of these controls, cold air is generated around the refrigeration evaporator 52, and the cold air is circulated in the refrigeration space 20 by the refrigeration fan 28, whereby the refrigeration space 20 is cooled to the refrigeration temperature.

  When the refrigeration space 30 is cooled (refrigeration cooling), the microcomputer 70 closes the refrigeration side outlet 50 of the switching valve 43 and opens the refrigeration side outlet 60, thereby causing the refrigerant to flow to the refrigeration evaporator 62. The evaporator 62 is operated. Further, the microcomputer 70 rotates the refrigeration fan 38. As a result of these controls, cold air is generated around the freezing evaporator 62, and the cold air is circulated in the freezing space 30 by the freezing fan 38, and the freezing space 30 is cooled to the freezing temperature.

  When defrosting the refrigeration evaporator 62, the microcomputer 70 energizes the defrost heater 65 to warm it and melt the frost attached to the refrigeration evaporator 62. In addition, the water generated when the frost is melted by the defrosting is collected by a basket or the like provided under the freezing evaporator 62.

  Further, when performing so-called pump-down in which the refrigerant is extracted from the refrigeration evaporator 62, the microcomputer 70 closes the refrigeration side outlet 50 and the refrigeration side outlet 60 of the switching valve 43, operates the compressor 41, and freezes the refrigerant. It moves from the evaporator 62 to the compressor 41 side.

  The microcomputer 70 performs basic operation control that alternately executes refrigeration cooling and refrigeration cooling. In the basic operation control, normally, when the refrigeration cooling is finished, the pump down is performed, the refrigerant necessary for the refrigeration cooling is extracted from the refrigeration evaporator 62, and then the refrigeration cooling is performed. Since the amount of refrigerant necessary for refrigeration cooling is smaller than the amount of refrigerant necessary for refrigeration cooling, the pump down time before refrigeration cooling in the basic operation control may be short.

  When a predetermined defrosting start condition is satisfied during the basic operation control, the microcomputer 70 temporarily stops the basic operation control and executes the defrosting control while the basic operation control is stopped. The defrosting start condition is a condition that is determined in advance as that defrosting should be performed when the condition is satisfied. The content of the defrosting start condition is not limited. For example, when the freezing space 30 becomes a predetermined temperature or lower, when a certain time has elapsed since the completion of the previous defrosting, or when the total time for freezing and cooling reaches a certain time, the microcomputer 70 It is determined that the frost start condition is satisfied. In order to prevent the temperature in the refrigeration space 30 from rising excessively during the defrosting control, the defrosting control is executed after the refrigeration cooling in the basic operation control. When the defrosting start condition is satisfied during the refrigeration cooling in the basic operation control, the process proceeds to the defrosting control as it is. When the defrosting start condition is satisfied when the cooling is not performed, the process moves to the defrosting control after the subsequent cooling and cooling.

  A flowchart of the defrosting control is shown in FIG. When the defrosting control is started (S1), the microcomputer 70 starts pumping down (S2) and removes the refrigerant from the refrigeration evaporator 62. When the pump-down end condition is satisfied (Yes in S3), the microcomputer 70 ends the pump-down (S4). The microcomputer 70 terminates the pump down when, for example, a preset time period has elapsed since the start of the pump down, or when the time obtained by multiplying the rotation speed of the compressor 41 by a coefficient has elapsed since the start of the pump down. Judge that the condition is satisfied. Thereafter, the microcomputer 70 energizes the defrosting heater 65 and starts defrosting the freezing evaporator 62 (S5).

  The microcomputer 70 performs refrigeration cooling during the defrosting of the freezing evaporator 62 as a part of the defrosting control. The refrigeration cooling during the defrosting of the refrigeration evaporator 62 is started simultaneously with the start of the defrosting or after a certain time has elapsed after the start of the defrosting (S6).

  In the refrigeration cooling during the defrosting of the refrigeration evaporator 62, the amount of the refrigerant flowing through the refrigeration evaporator 52 is equal to the amount during the refrigeration cooling in the basic operation control or more than the amount during the refrigeration cooling in the basic operation control. Done less. Although the method is not limited, three methods will be exemplified here.

  The first method is a method of reducing the opening degree of the variable valve provided upstream of the refrigeration evaporator 52 in the refrigerant flow. Specifically, the microcomputer 70 makes the opening of the variable valve smaller during refrigeration cooling during defrosting of the refrigeration evaporator 62 than during refrigeration cooling in the basic operation control. The switching valve 43 may function as such a variable valve. A variable valve different from the switching valve 43 may be provided between the switching valve 43 and the refrigeration evaporator 52, and the other variable valve may change the amount of refrigerant flowing to the refrigeration evaporator 52.

  A cooling cycle 140 for carrying out the second method is shown in FIG. The cooling cycle 140 in FIG. 5 differs from the cooling cycle 40 in FIG. 2 in that two refrigeration capillary tubes 151 a and 151 b are provided in parallel between the switching valve 143 and the refrigeration evaporator 52. In FIG. 5, the same devices as those used in the cooling cycle 40 of FIG. 2 are denoted by the same reference numerals as those in FIG. 2. The two chilled capillary tubes 151a and 151b have different aperture sizes. One refrigeration capillary tube 151a has a small throttle and allows a large amount of refrigerant to pass therethrough. The other refrigeration capillary tube 151b has a larger throttle than the refrigeration capillary tube 151a, and less refrigerant can pass through the refrigeration capillary tube 151a than the refrigeration capillary tube 151a. Such a difference in the size of the restriction is caused by a difference in the diameter or length of the capillary tube for refrigeration. The smaller the diameter of the refrigerated capillary tube, the larger the restriction. In addition, the longer the length of the chilled capillary tube, the larger the aperture. In the cooling cycle 140 of FIG. 5, the switching valve 143 has two refrigeration side outlets 150a and 150b, one refrigeration side outlet 150a is connected to one refrigeration capillary tube 151a, and the other refrigeration side outlet 150b is connected to the other. Each is connected to the refrigeration capillary tube 151b. The microcomputer 70 can select either one of the two refrigeration capillary tubes 151a and 151b as a flow path by switching the switching valve 143 when the refrigerant is allowed to flow to the refrigeration evaporator 52. ing.

  However, the switching valve is the same as the switching valve 43 in FIG. 2 having only one outlet on the refrigeration evaporator 52 side, the outlet on the refrigeration evaporator 52 side of the switching valve 43 and two refrigeration capillary tubes. Another switching valve may be provided between 151a and 151b. And the flow path of a refrigerant | coolant may be made | formed so that a refrigerant | coolant may be flowed through either one of the two refrigeration capillary tubes 151a and 151b with the said another switching valve. Further, three or more refrigeration capillary tubes having different squeezing amounts may be provided. In that case, during the refrigeration cooling during the defrosting of the refrigeration evaporator 62, the microcomputer 70 supplies the refrigerant to the capillary tube having a larger throttle than the capillary tube through which the refrigerant flows during the operation of the refrigeration evaporator 52 in the basic operation control. Shed.

  In the cooling cycle 140 having the above-described configuration, when performing refrigeration cooling in the basic operation control, the microcomputer 70 causes the refrigerant to flow through the refrigeration capillary tube 151a having the smaller throttle. On the other hand, when performing refrigeration cooling during defrosting of the refrigeration evaporator 62, the microcomputer 70 causes the refrigerant to flow through the refrigeration capillary tube 151b having the larger throttle.

  The third method is a method in which the microcomputer 70 reduces the rotational speed of the compressor 41 during refrigeration cooling during defrosting of the refrigeration evaporator 62. In this case, for example, the rotation speed of the compressor 41 during refrigeration cooling during defrosting of the refrigeration evaporator 62 is half of the rotation speed during refrigeration cooling in the basic operation control.

  During the refrigeration cooling during the defrosting of the refrigeration evaporator 62, it is desirable that the microcomputer 70 increases the rotational speed of the refrigeration fan 28 than during the execution of the refrigeration cooling in the basic operation control.

  While the refrigeration cooling during the defrosting of the refrigeration evaporator 62 is being performed, the temperature in the refrigerated space 20 is measured by the refrigerated space temperature sensor 29. When the temperature in the refrigerated space 20 becomes lower than the preset target temperature (Yes in S7), the refrigeration cooling is finished even during defrosting (S8). Even after the end of the refrigeration cooling, the defrosting is continued until the defrosting end condition is satisfied. When the defrosting end condition is satisfied (Yes in S9), the defrosting ends (S10). When the defrosting is finished, the defrosting control is finished (S11). On the other hand, while the temperature in the refrigerated space 20 is equal to or higher than a preset target temperature (No in S7), the refrigeration cooling is continued as long as the defrosting termination condition is not satisfied (No in S12). However, even if the temperature in the refrigerated space 20 is equal to or higher than the preset target temperature (No in S7), if the defrosting end condition is satisfied (Yes in S12), the refrigeration cooling ends (S13), Defrosting ends (S14). When the defrosting is finished, the defrosting control is finished (S11). In the flowchart of FIG. 4, the defrosting is finished after the refrigeration cooling is finished, but the order of finishing may be reversed. Moreover, the completion | finish of refrigeration cooling and the completion | finish of a defrost may be performed simultaneously. In addition, the detailed content of the defrost termination conditions is not limited. For example, when the temperature measured by the temperature sensor 66 that measures the temperature of the refrigeration evaporator 62 is equal to or higher than a preset temperature, the microcomputer 70 determines that the defrosting termination condition is satisfied.

  After the defrosting control is completed, the microcomputer 70 starts basic operation control. Since the temperature of the refrigeration evaporator 62 rises due to the defrosting of the refrigeration evaporator 62, the basic operation control after the completion of the defrost control starts with refrigeration cooling in order to lower the temperature of the refrigeration evaporator 62.

  In addition to the defrosting of the refrigerating evaporator 62 performed in the defrosting control, the defrosting of the refrigerating evaporator 52 is also performed when a predetermined condition is satisfied.

  The effect of the above embodiment is as follows.

  In the above embodiment, since the refrigeration evaporator 52 is operated even during the defrosting of the refrigeration evaporator 62, the time during which the refrigeration cooling stops is shortened, and the temperature rise of the refrigeration space 20 is suppressed.

  Further, as described above, before the refrigeration evaporator 62 is defrosted, the pump down for recovering the refrigerant of the refrigeration evaporator 62 to the compressor 41 is performed. Since a large amount of refrigerant is recovered by this pump-down, when the recovered refrigerant flows into the refrigeration evaporator 52 as it is, the refrigerant cannot be completely evaporated by the refrigeration evaporator 52 and the refrigeration accumulator 53 is a liquid refrigerant. The liquid refrigerant flows into the compressor 41 and the compressor 41 may be broken. However, in the above embodiment, the microcomputer 70 uses the amount of the refrigerant flowing to the refrigeration evaporator 52 during the refrigeration cooling during the defrosting of the refrigeration evaporator 62, and the refrigeration evaporator during the refrigeration cooling in the basic operation control. The amount of refrigerant flowing to 52 is equal to or less than that. Therefore, the liquid refrigerant flowing into the refrigeration evaporator 52 can be prevented from flowing into the compressor 41 without being completely evaporated by the refrigeration evaporator 52, and the compressor 41 can be prevented from being broken.

  In the case of the above embodiment, a refrigeration accumulator 53 as a gas-liquid separator is connected between the refrigeration evaporator 52 and the compressor 41, and the liquid refrigerant is recovered by the refrigeration accumulator 53. Therefore, even if the microcomputer 70 reduces the amount of refrigerant flowing into the refrigeration evaporator 52 during refrigeration cooling during the defrosting of the refrigeration evaporator 62, the liquid refrigerant flows out of the refrigeration evaporator 52. However, it is possible to prevent the liquid refrigerant from flowing into the compressor 41 downstream of the refrigeration accumulator 53, and to prevent the compressor 41 from being broken.

  Further, when the number of rotations of the refrigeration fan 28 is larger during refrigeration cooling during defrosting of the refrigeration evaporator 62 than during refrigeration cooling in the basic operation control, the heat exchange efficiency in the refrigeration evaporator 52 is improved. Thus, a large amount of refrigerant evaporates in the refrigeration evaporator 52. Therefore, it becomes difficult for the liquid refrigerant to flow out of the refrigeration evaporator 52, the liquid refrigerant can be prevented from flowing into the compressor 41, and the compressor 41 can be prevented from being broken.

  Further, when the temperature in the refrigerated space 20 becomes lower than a preset target temperature, the refrigerated cooling is terminated even during the defrosting of the refrigeration evaporator 62, and therefore the temperature in the refrigerated space 20 is too low. Can be prevented.

  A modification of the above embodiment will be described.

  As one example of the change, there is an example in which the liquid refrigerant recovered by the refrigeration accumulator 53 is routed to another part in the cooling cycle and reused in the cooling cycle. One such modification is shown in FIG. The structure of the cooling cycle 240 of FIG. 6 is basically the same as the structure of the cooling cycle 40 of the embodiment of FIG. However, in the cooling cycle 240 of FIG. 6, a pipe 254 that connects a portion between the refrigeration capillary tube 51 and the refrigeration evaporator 52 and the refrigeration accumulator 53 is provided. The liquid refrigerant recovered by the refrigeration accumulator 53 is configured to be returned to the upstream portion of the refrigerant flow from the refrigeration evaporator 52. In the cooling cycle 240 having this configuration, the recovered liquid refrigerant is reused in the cooling cycle 240, so that it is not wasted. In FIG. 6, the same reference numerals as those in FIG. 2 are assigned to the same devices and the like used in the cooling cycle 40 in FIG. 2.

  Another modification will be described. In the above embodiment, when refrigeration cooling is performed during defrosting of the refrigeration evaporator 62, the amount of refrigerant flowing to the refrigeration evaporator 52 is always equal to or equal to the amount during refrigeration cooling in the basic operation control. Controlled to be less. However, the microcomputer 70 reduces the amount of refrigerant flowing to the refrigeration evaporator 52 only when other conditions are satisfied in addition to the refrigeration cooling being performed during the defrosting of the refrigeration evaporator 62. You may control as follows.

  For example, a sensor that detects that a liquid refrigerant has flowed into the refrigeration accumulator 53 may be provided. The microcomputer 70 is in a state where refrigeration cooling is performed during the defrosting of the refrigeration evaporator 62 and the sensor detects that liquid refrigerant has flowed into the refrigeration accumulator 53. In addition, the refrigerant flowing through the refrigeration evaporator 52 may be less than before the detection. The method of reducing the refrigerant flowing through the refrigeration evaporator 52 is as described in the above embodiment.

  In this modified example, the sensor that detects that the liquid refrigerant has flowed into the refrigeration accumulator 53 can be any sensor that can directly or indirectly detect that the liquid refrigerant has flowed into the refrigeration accumulator 53. good. For example, this sensor may be a temperature sensor. When the liquid refrigerant flows into the refrigeration accumulator 53, the temperature of the refrigeration accumulator 53 decreases. Therefore, when the temperature sensor detects a temperature drop of the refrigeration accumulator 53, the microcomputer 70 can determine that it has detected that a liquid refrigerant has flowed into the refrigeration accumulator 53.

  Also in the case of the method of this modified example, refrigeration cooling can be performed during the defrosting of the refrigeration evaporator 62 while preventing the liquid refrigerant from flowing into the compressor 41. Therefore, the time during which the refrigeration cooling stops is shortened, and the temperature rise of the refrigerated space 20 is suppressed.

  Another modification will be described. In this modified example, as in the above-described embodiment, when the refrigeration cooling is performed during the defrosting of the refrigeration evaporator 62, the microcomputer 70 always has the amount of refrigerant flowing through the refrigeration evaporator 52 as the basic amount. The amount is controlled to be equal to or less than the amount during refrigeration cooling in the operation control. And when another condition is satisfy | filled, the microcomputer 70 is controlled so that the refrigerant | coolant which flows into the refrigeration evaporator 52 becomes still smaller. Specifically, when the microcomputer 70 starts the refrigeration cooling during the defrosting of the refrigeration evaporator 62, the amount of the refrigerant flowing through the refrigeration evaporator 52 is equal to the amount during the refrigeration cooling in the basic operation control or Control to be less than this. Under the circumstances, for example, when the sensor detects that the liquid refrigerant has flowed into the refrigeration accumulator 53, the microcomputer 70 reduces the refrigerant flowing to the refrigeration evaporator 52 more than before the detection. . The method of reducing the refrigerant flowing through the refrigeration evaporator 52 is as described in the above embodiment. Also in the case of the method of this modified example, refrigeration cooling can be performed during the defrosting of the refrigeration evaporator 62 while preventing the liquid refrigerant from flowing into the compressor 41. Therefore, the time during which the refrigeration cooling stops is shortened, and the temperature rise of the refrigerated space 20 is suppressed.

  In any of the above-described modified examples, when the refrigeration cooling is performed during the defrosting of the refrigeration evaporator 62, it is desirable to increase the rotational speed of the refrigeration fan 28 than during the basic operation control.

  Still another modification will be described. In the above embodiment, when refrigeration cooling is performed during defrosting of the refrigeration evaporator 62, the amount of refrigerant flowing to the refrigeration evaporator 52 is equal to or less than the amount during refrigeration cooling in the basic operation control. It is controlled to become. However, in this modified example, the microcomputer 70 does not perform this control. Nevertheless, there is a method in which the microcomputer 70 can perform refrigeration cooling during the defrosting of the refrigeration evaporator 62 and can prevent the liquid refrigerant from flowing into the compressor 41 and breaking the compressor 41. Three examples are given. In any example, the microcomputer 70, as a general rule, also has the amount of refrigerant flowing through the refrigeration evaporator 52 equal to the amount during refrigeration cooling in the basic operation control even during refrigeration cooling during defrosting of the refrigeration evaporator 62. Do not control to be equal or less.

  The first example is a method in which the refrigeration accumulator 53 collects the liquid refrigerant flowing out of the refrigeration evaporator 52 regardless of whether or not the refrigeration evaporator 62 is being defrosted. In order to carry out this method, it is desirable that the refrigeration accumulator 53 is a material that can collect a large amount of liquid.

  In the second example, when the microcomputer 70 detects that the liquid refrigerant has flowed into the refrigeration accumulator 53 regardless of whether or not the refrigeration evaporator 62 is being defrosted, the microcomputer 70 starts from before the detection. This is a method of reducing the amount of refrigerant flowing through the refrigeration evaporator 52. In order to carry out this method, the refrigeration accumulator 53 is provided with a sensor for detecting the inflow of the liquid refrigerant. The specific method for reducing the refrigerant is not limited.

  In the first example and the second example, the liquid refrigerant can be prevented from flowing into the compressor 41 during the defrosting of the refrigeration evaporator 62 and at other times. Therefore, it is possible to operate the refrigeration evaporator 52 while preventing the compressor 41 from being broken by the inflow of the liquid refrigerant. Therefore, the time during which the refrigeration cooling stops is shortened, and the temperature rise of the refrigerated space 20 is suppressed.

  The third example is a method in which the microcomputer 70 increases the rotational speed of the refrigeration fan 28 during refrigeration cooling during the defrosting of the refrigeration evaporator 62 than during basic operation control. By increasing the rotational speed of the refrigeration fan 28, the heat exchange efficiency in the refrigeration evaporator 52 is improved, and a large amount of refrigerant evaporates in the refrigeration evaporator 52, so that the liquid refrigerant becomes the refrigeration evaporator 52. It can be prevented from flowing out into the compressor 41. Therefore, even during the defrosting of the refrigeration evaporator 62, the refrigeration evaporator 52 can be operated while preventing the compressor 41 from being broken by the inflow of the liquid refrigerant. Therefore, the time during which the refrigeration cooling stops is shortened, and the temperature rise of the refrigerated space 20 is suppressed.

  The above embodiment is an illustration and the scope of the invention is not limited to this. The above embodiments can be implemented in various other forms, and various omissions, substitutions, and changes can be made without departing from the scope of the invention. The above embodiments and modifications thereof are included in the inventions described in the claims and their equivalents.

DESCRIPTION OF SYMBOLS 10 ... Refrigerator, 12 ... Refrigerator main body, 14 ... Thermal insulation partition wall, 20 ... Refrigeration space, 22 ... Refrigeration room, 24 ... Storage container, 26 ... Vegetable room, 28 ... Refrigeration fan, 29 ... Temperature sensor for refrigeration space, 30 Refrigeration space, 32 ... Ice making room, 34 ... Refrigeration room, 38 ... Refrigeration fan, 39 ... Temperature sensor for refrigeration space, 40 ... Cooling cycle, 41 ... Compressor, 42 ... Condenser, 43 ... Switching valve, 50 ... Refrigeration side outlet, 51 ... Refrigeration capillary tube, 52 ... Refrigeration evaporator, 53 ... Refrigeration accumulator, 56 ... Temperature sensor, 60 ... Refrigeration side outlet, 61 ... Refrigeration capillary tube, 62 ... Refrigeration evaporator, 63 ... Refrigeration accumulator, 64 ... Check valve, 65 ... Defrost heater, 66 ... Temperature sensor, 70 ... Microcomputer, 140 ... Cooling cycle, 143 ... Switching valve, 150a, 150b ... Refrigerated Outlet, 151a, 151b ... refrigeration capillary tube, 240 ... cooling cycle, 254 ... pipe

Claims (8)

A compressor, a condenser, and a switching valve are connected in this order, a refrigeration evaporator is connected to a first outlet of the switching valve, a refrigeration evaporator is connected to a second outlet of the switching valve, and the refrigeration A cooling cycle in which an evaporator and the refrigeration evaporator are connected to the compressor;
A defroster for defrosting the refrigeration evaporator;
A controller that controls the cooling cycle and the defroster;
The control unit performs basic operation control in which the refrigeration evaporator and the refrigeration evaporator are operated alternately, and when the defrosting start condition is satisfied, the refrigeration evaporator in the basic operation control. The basic operation control is temporarily stopped after the operation, and the defrosting control is executed.
In the defrosting control, after the refrigerant in the refrigeration evaporator is recovered by the compressor, the refrigeration evaporator is defrosted by the defroster, and the refrigeration evaporator is used during the defrosting. Is characterized by driving,
refrigerator.   The control unit determines the amount of refrigerant flowing through the refrigeration evaporator during operation of the refrigeration evaporator in the defrosting control, and the refrigeration evaporation during operation of the refrigeration evaporator in the basic operation control. The refrigerator according to claim 1, wherein the refrigerator is equal to or less than an amount of refrigerant flowing in the container.   The control unit reduces the opening of a variable valve provided upstream of the refrigerant from the refrigeration evaporator, and the refrigeration evaporator during operation of the refrigeration evaporator in the defrosting control. The refrigerator according to claim 2, wherein the amount of refrigerant flowing in the refrigerator is equal to or less than the amount of refrigerant flowing in the refrigeration evaporator during operation of the refrigeration evaporator in the basic operation control. A plurality of capillary tubes having different throttle sizes are connected in parallel between the switching valve and the refrigeration evaporator,
The control unit causes the refrigerant to flow through the capillary tube having a larger throttle than the capillary tube through which the refrigerant flows during operation of the refrigeration evaporator in the basic operation control. The amount of refrigerant flowing through the refrigeration evaporator during operation is made equal to or less than the amount of refrigerant flowing through the refrigeration evaporator during operation of the refrigeration evaporator in the basic operation control. Refrigerator.   The control unit reduces the number of revolutions of the compressor, thereby reducing the amount of refrigerant flowing to the refrigeration evaporator during the operation of the refrigeration evaporator in the defrosting control, in the basic operation control. The refrigerator according to claim 2, wherein the amount is equal to or less than the amount of refrigerant flowing through the refrigeration evaporator during operation of the refrigeration evaporator.   The refrigerator according to any one of claims 1 to 5, wherein a gas-liquid separator is connected between the refrigeration evaporator and the compressor, and a liquid refrigerant is recovered by the gas-liquid separator.   A sensor that detects that liquid refrigerant has flowed into the gas-liquid separator is provided, and when the sensor performs the detection, the control unit causes the refrigerant flowing in the refrigeration evaporator to flow more than before the detection. The refrigerator according to claim 6, which is reduced. A fan for circulating cold air around the refrigeration evaporator;
The control unit makes the rotational speed of the fan during operation of the refrigeration evaporator in the defrosting control larger than the rotational speed of the fan during operation of the refrigeration evaporator in the basic operation control. The refrigerator according to any one of claims 1 to 7.

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