JP4104900B2 - refrigerator - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a refrigerator in which an evaporator is provided in each of a refrigerator compartment and a freezer compartment.
[0002]
[Prior art]
Generally, a refrigerator constitutes a refrigeration cycle in which refrigerant discharged from a compressor passes through a condenser, a throttling mechanism (capillary tube), and an evaporator, and then returns to the compressor. It was cooling.
[0003]
On the other hand, in recent years, evaporators are placed in the refrigerator compartment and freezer compartment via capillary tubes of arbitrary diameters, and the refrigerator mode for cooling the refrigerator compartment by switching the refrigerant flow path and the refrigerator mode for cooling the freezer compartment are alternated. In addition, a refrigerator has been proposed in which the temperature is controlled to an evaporation temperature suitable for the temperature zone of each room by cooling the compressor and changing the rotation speed of the compressor.
[0004]
That is, the refrigerant leaving the compressor selectively controls the flow to the refrigerated capillary tube connected to the refrigeration chamber evaporator and the refrigeration capillary tube connected to the freezer compartment evaporator by the switching valve.
[0005]
Further, an accumulator and a check valve are connected to the outlet of the freezer compartment evaporator, join with a pipe connected from the outlet of the refrigerator compartment evaporator, and return to the compressor (Japanese Patent Application No. 11-173729).
[0006]
In the refrigeration cycle as described above, the following control method has also been proposed (Japanese Patent Application No. 2000-254132).
[0007]
That is, the switching valve is fully closed to shut off the refrigerant flow path, and then the compressor is stopped. After a predetermined time or when the internal temperature reaches the set temperature, the switching valve is set to the refrigeration mode. And in order to perform each cooling mode efficiently, before switching a cooling chamber to the refrigerator compartment side, the refrigerant | coolant recovery mode which interrupts | blocks both the refrigerant | coolant flow paths of a refrigerator side and a freezing side, and retains a refrigerant | coolant on the high voltage | pressure side is performed. .
[0008]
In other words, by repeating the steps of the refrigeration mode, the fully closed state (refrigerant recovery mode), and the refrigeration mode, the necessary refrigerant is moved to the condenser before the refrigeration mode, eliminating the refrigerant delay in the refrigeration mode and A low temperature refrigerant is retained in the chamber by the action of a check valve that utilizes the pressure difference between the refrigerator compartment and the freezer compartment.
[0009]
[Problems to be solved by the invention]
In the refrigerator having the refrigeration cycle as described above, high cooling cycle efficiency can be obtained because cooling can be performed at a temperature suitable for each evaporation temperature for each cooling chamber.
[0010]
On the other hand, when the compressor is stopped, the switching valve is fully closed to prevent the high-temperature refrigerant on the condenser side from flowing into the evaporator. In preparation for starting up the compressor, the engine is switched from the fully closed state to the refrigeration mode or the refrigeration mode in order to achieve a pressure balance between the low temperature side and the high temperature side before starting.
[0011]
However, in such a control method, there is a limit in shortening the time until the pressure balance required during the startup of the compressor. In other words, it takes time to reduce the pressure difference between the high pressure side and the low pressure side that does not adversely affect the start of the compressor even if only one of the refrigerating side or the freezing side is opened as a preparation for starting the compressor. There was a problem.
[0012]
In addition, since the high-temperature refrigerant flows into the evaporator, the time until the start-up has a problem of adversely affecting power consumption reduction.
[0013]
Therefore, in view of the above problems, the present invention provides a refrigerator that can perform pressure balancing between the high-pressure side and the low-pressure side of the refrigeration cycle, which is a necessary condition for starting the compressor, in a short time, and can perform efficient cooling. To do.
[0014]
[Means for Solving the Problems]
According to the first aspect of the present invention, a compressor, a condenser, and a switching valve are sequentially connected, and a refrigeration cycle in which a refrigerator compartment evaporator and a freezer compartment evaporator are connected to each other via a throttle mechanism is connected to the switching valve. And by alternately switching the refrigerant flow path to the refrigerating room evaporator or the freezing room evaporator with the switching valve, the refrigerating mode for cooling the refrigerating room and the refrigerating mode for cooling the freezing room are alternately performed. In the refrigerator to be performed, when the control means of the refrigerator stops the compressor, the switching valve is fully closed so that the refrigerant does not flow through either the refrigerator compartment evaporator or the freezer compartment evaporator. When the compressor is stopped and the control means starts the compressor, Prior to starting the compressor The refrigerator is characterized in that the compressor is started after the switching valve is fully opened and the refrigerant flows into both the refrigerator compartment evaporator and the freezer compartment evaporator.
[0015]
According to a second aspect of the present invention, when the controller starts the compressor, the switching valve is fully opened when the internal temperature reaches the switching set temperature T1, and the internal temperature is the compressor starting temperature. 2. The refrigerator according to claim 1, wherein the compressor is started when T0 (T0> T1) is reached.
[0016]
According to a third aspect of the present invention, the control means sets the switching set temperature T1 when the outside air temperature is lower than the reference temperature Tg, and lower than the switching set temperature T1 when the outside air temperature is higher than the reference temperature Tg. It is a refrigerator of Claim 2 characterized by the above-mentioned.
[0017]
According to a fourth aspect of the present invention, when the control means starts the compressor, the switching valve is fully opened when the internal temperature reaches the compressor starting temperature T0, and is started from the fully opened state. The refrigerator according to claim 1, wherein the compressor is started after the preparation time K has elapsed.
[0018]
According to a fifth aspect of the present invention, the control means sets the start preparation time K when the outside air temperature is lower than the reference temperature Tg, and shorter than the start preparation time K when the outside air temperature is higher than the reference temperature Tg. It is a refrigerator of Claim 4 characterized by the above-mentioned.
[0019]
In the invention of claim 6, a compressor, a condenser, and a switching valve are sequentially connected, and a refrigeration cycle in which a refrigerator compartment evaporator and a freezer compartment evaporator are connected to each other via a throttle mechanism is connected to the switching valve. And by alternately switching the refrigerant flow path to the refrigerating room evaporator or the freezing room evaporator with the switching valve, the refrigerating mode for cooling the refrigerating room and the refrigerating mode for cooling the freezing room are alternately performed. In the refrigerator to be performed, when the refrigerator is turned on and the compressor is started, the control means sets the switching valve to a fully open state during the start preparation time K, and the refrigerator compartment evaporator The refrigerator is characterized in that the compressor is started after the refrigerant flows into either of the freezer evaporators.
[0020]
According to the seventh aspect of the present invention, a compressor, a condenser, and a changeover valve are sequentially connected, and a refrigerating cycle in which a refrigerator compartment evaporator and a freezer compartment evaporator are connected to each other via a throttle mechanism is connected to the changeover valve. And by alternately switching the refrigerant flow path to the refrigerating room evaporator or the freezing room evaporator with the switching valve, the refrigerating mode for cooling the refrigerating room and the refrigerating mode for cooling the freezing room are alternately performed. In the refrigerator to be performed, when the control unit of the refrigerator detects that the compressor cannot be started and then restarts the compressor, the switching valve is fully opened during the start preparation time K. The refrigerator is characterized in that the compressor is restarted after the refrigerant flows in both the refrigerator compartment evaporator and the freezer compartment evaporator.
[0021]
The invention according to claim 8 is characterized in that the control means maintains the fully open state of the switching valve for a fully open holding time from when the compressor is started. It is a refrigerator as described in.
[0022]
According to a ninth aspect of the present invention, in the refrigeration cycle, the refrigeration throttle mechanism and the refrigeration chamber evaporator are sequentially connected to a first outlet of the switching valve, and the refrigeration is connected to a second outlet of the switching valve. The throttling mechanism for use and the freezer compartment evaporator are connected in order, and the refrigerator compartment evaporator and the freezer compartment evaporator are connected to the compressor. It is a refrigerator as described in one term.
[0023]
According to a tenth aspect of the present invention, in the refrigeration cycle, the refrigeration throttle mechanism and the refrigeration chamber evaporator are sequentially connected to a first outlet of the switching valve, and the refrigeration is connected to a second outlet of the switching valve. A squeezing mechanism for refrigeration is connected, the refrigeration squeezing mechanism and the refrigerator compartment evaporator are connected to the refrigeration compartment evaporator, and the refrigeration compartment evaporator is connected to the compressor. It is a refrigerator as described in at least 1 among 1-8.
[0024]
In the case of the operation of the first aspect, in the case of the operation in which the compressor is repeatedly started and stopped, the switching valve is fully closed to recover the high-pressure refrigerant and then the compressor is stopped. Thereafter, when the compressor is started, the compressor is prepared for start-up in the fully opened state, and the pressure balance between the high-pressure side and the low-pressure side is made equal.
[0025]
As a result, while the compressor is stopped, the fully closed state in which the high-pressure refrigerant suppresses the inflow to the evaporator side can be maintained for a long time, and the high-pressure side and the low-pressure side of the refrigeration cycle that are necessary conditions for starting the compressor thereafter. The pressure balance can be performed in a short time.
[0026]
According to the second aspect of the present invention, when the compressor is stopped, the fully-closed state that suppresses the inflow of the high-pressure refrigerant into the evaporator until the pressure difference between the high-pressure side and the low-pressure side reaches the pressure difference necessary for starting the compressor. The state can be maintained for a long time.
[0027]
According to the invention of claim 3, since the compressor can stand by to the pressure difference required for starting even if the outside air temperature fluctuates, it is possible to suppress the inflow of high-temperature refrigerant as much as possible and to reliably start the compressor. It becomes possible.
[0028]
According to the invention of claim 4, even when the internal temperature suddenly rises due to opening / closing of the door or turning on the load while the compressor is stopped and the starting temperature of the compressor is reached in a short time, the compressor is started. The system waits until the necessary pressure difference, and can prevent troubles such as failure to start the compressor due to the large pressure difference.
[0029]
According to the invention of claim 5, even if the door is opened or closed or a load is applied, the compressor can stand by to the pressure difference necessary for starting, so that the inflow of the high-temperature refrigerant can be suppressed as much as possible.
[0030]
According to the sixth aspect of the present invention, after the refrigerator is turned on, the switching valve is fully opened during the start-up preparation time K, and the pressure balance between the high pressure side and the low pressure side of the refrigeration cycle is performed. Can be reliably started.
[0031]
According to the seventh aspect of the present invention, when the start of the compressor fails and the compressor is restarted, the switching valve is fully opened during the start preparation time K, and the high pressure side and the low pressure side of the refrigeration cycle are After the pressure balance is performed, the compressor is restarted, so that the restart can be performed reliably.
[0032]
According to the eighth aspect of the present invention, the pressure balance between the high-pressure side and the low-pressure side in the refrigeration cycle can be reliably performed by opening the switching valve during the fully open holding time after starting the compressor. The subsequent steady rotation of the compressor can be performed smoothly.
[0033]
DETAILED DESCRIPTION OF THE INVENTION
(First embodiment)
Hereinafter, the first embodiment of the present invention will be described in detail with reference to the drawings.
[0034]
(1) Refrigerator structure
FIG. 1 is a cross-sectional view of a cold-cooled refrigerator showing the present embodiment.
[0035]
The refrigerator body 1 is formed of a heat insulating box 9 and an inner box 8. And it is divided into the refrigeration temperature zone (henceforth R room) 30 and the freezing temperature zone (henceforth F room) 40 by the heat insulation partition wall 2, and the cold air of these rooms is completely independent, and each cold air mixes. It has no structure.
[0036]
The inside of the R room 30 is divided into the refrigerated room 4 and the vegetable room 5 by the refrigeration partition plate 3, and the inside of the F room 40 is composed of the first freezing room 6 and the second freezing room 7, and each room is opened and closed. It has doors 51-54.
[0037]
A refrigerator compartment evaporator (hereinafter referred to as “R EVA”) 10 and a refrigerator compartment cooling fan (hereinafter referred to as “R fan”) 11 are arranged on the back of the vegetable compartment 5. Driven. The rear surface of the refrigerator compartment 4 serves as a cold air circulation path 18 for supplying cold air into the R chamber 30. The R fan 11 is variable speed by inverter control.
[0038]
A freezer compartment evaporator (hereinafter referred to as “F EVA”) 12 and a freezer compartment cooling fan (hereinafter referred to as “F fan”) 13 are arranged on the back walls of the first and second freezer compartments 6 and 7, and circulates the cold air. The 1st and 2nd freezer compartments 6 and 7 are cooled. The F fan 12 is variable speed by inverter control.
[0039]
A compressor 15 and a condenser 21 are arranged in the machine room 14 below the back wall of the refrigerator body 1. Further, a fan (hereinafter referred to as C fan) 25 that radiates heat from the condenser 21 is provided. The C fan 25 is variable speed by inverter control. The compressor 15 is driven by a brushless DC motor and has variable capacity. The brushless DC motor has three phases, and its rotation is inverter controlled by a drive current from an inverter circuit.
[0040]
Further, defrosting heaters 60 and 62 are disposed below the R and F EVAs 10 and 12.
[0041]
Furthermore, the control part 64 consisting of the microcomputer which controls this refrigerator is provided in the back upper part of the refrigerator main body 1. As shown in FIG. The control unit 64 performs inverter control on ON and OFF and the rotation speed of the brushless DC motors that are the brushless DC motor of the compressor 15 and the fan motors of the R fan 11, the F fan 12, and the C fan 25. For example, in the case of a brushless DC motor of the compressor 15, a rotation speed signal is sent to the inverter circuit for control. Moreover, the defrosting heaters 60 and 62 are controlled, and further, the switching valve 22 described later is controlled.
[0042]
(2) Configuration of refrigeration cycle
FIG. 2 is a refrigeration cycle of the refrigerator.
[0043]
After the nonflammable refrigerant discharged from the compressor 15 passes through the condenser 21, the refrigerant flow path is switched by the refrigerant switching mechanism of the switching valve 22 including a three-way valve.
[0044]
The refrigerating capillary tube 23 and the R evaporator 10 are sequentially connected to one outlet of the switching valve 22, and the refrigeration capillary tube 24, the F evaporator 12 and the accumulator 16 are sequentially connected to the other outlet of the switching valve 22.
[0045]
Under the control of the control unit 64, the switching valve 22 is in a state in which the refrigerant is sent only to the refrigerated capillary tube 23, a state in which the refrigerant is sent only to the frozen capillary tube 24, a fully open state in which the refrigerant is sent to both, and a fully closed state in which neither refrigerant is sent. Four states can be realized.
[0046]
A check valve 17 is connected to the outlet pipe of the accumulator 16 in the machine chamber 14, and the outlet side of the check valve 17 merges with the outlet pipe of the R EVA 10 and is connected to the suction side of the compressor 15.
[0047]
(3) Alternate operation
First, the normal internal temperature control operation in the refrigerator will be described.
[0048]
The high-temperature refrigerant compressed and pressurized by the compressor 15 is radiated by the condenser 21, and the refrigerant discharged from the refrigerant enters the switching valve 22, cools the R-evaporator 10 or the F-evaporator 12, and the refrigeration mode described below. And alternate operation in which the refrigeration mode is alternated.
[0049]
(3-1) Refrigeration mode
When the internal temperature of the R chamber 30 becomes higher than the set temperature, the refrigeration mode is performed.
[0050]
As shown in FIG. 3A, in the refrigeration mode, the switching valve 22 is switched, the refrigerant flows through the refrigeration capillary tube 23, evaporates by the R evaporator 10, and the R chamber 30 is cooled. The evaporated and gasified refrigerant returns to the compressor 15. Since the temperature of the F EVA 12 is lower than the evaporation temperature in the refrigeration mode, the check valve 17 is installed in the flow path on the F EVA 12 side so that the refrigerant flows into the F EVA 12 and does not recondense.
[0051]
(3-2) Freezing mode
When the internal temperature of the F chamber 40 becomes higher than the set temperature, the freezing mode is performed.
[0052]
As shown in FIG. 3 (b), in the refrigeration mode, the switching valve 22 is switched, the refrigerant flow path is switched so that the refrigerant flows into the refrigeration capillary tube 24, the F evaporator 12 evaporates, and the accumulator 16 and the check valve 17 are switched. Return to the compressor 15.
[0053]
Since these evaporators 10 and 12 are heat exchangers that exchange heat with air by forced convection, the R fan 11 is operated in the refrigeration mode and the F fan 13 is operated simultaneously with the switching of the refrigerant flow path in the refrigeration mode. Cool inside.
[0054]
(4) Control method for stopping and starting the compressor 15
(4-1) Theoretical explanation of this control method
In the refrigeration mode and the refrigeration mode as described above, the compressor 15 stops when the internal temperature of each room is kept lower than the starting temperature of the compressor 15.
[0055]
If the switching valve 22 is in the refrigeration mode or the refrigeration mode when the compressor 15 is stopped, the pressure on the high pressure side and the low pressure side in the refrigeration cycle balances in a short time, so that the subsequent compressor 15 can be reliably started. . However, since the high-temperature refrigerant flows from the condenser 21 side, the evaporator temperature rises and affects the fluctuation of the internal temperature, leading to an increase in power consumption.
[0056]
Therefore, when the compressor 15 is stopped, the switching valve 22 is fully closed to suppress the inflow of the high-temperature refrigerant.
[0057]
FIG. 4 shows pressure fluctuations of the discharge pressure (high pressure side pressure) and the suction pressure (low pressure side pressure) of the compressor 15 at this time. While the compressor 15 is stopped, the discharge pressure gradually decreases as the temperature decreases. However, when the compressor 15 is started, a pressure difference of about 0.4 MPa exists. Sufficient reliability is not obtained to start the compressor 15 with this pressure difference, and in some cases, the compressor 15 cannot be started. That is, in order to start the compressor 15, it is necessary to reduce a pressure difference.
[0058]
Therefore, in the conventional technique (Japanese Patent Application No. 2000-254132), as preparation for starting the compressor 15, when the internal temperature reaches the starting temperature of the compressor 15, the switching valve 22 is set in the refrigeration mode. In this case, as shown in FIG. 5, the refrigerant on the condenser 21 side flows into the R evaporator 10 via the refrigerated capillary tube 23, and the pressure difference between the high pressure side and the low pressure side is gradually balanced. However, since this balance time depends only on the refrigerated capillary tube 23, a certain amount of time is required, and the temperature of the R EVA 10 increases due to the inflow of the high-temperature refrigerant during this time.
[0059]
Therefore, in the present control method, as shown in FIG. 3 (d), in preparation for starting the compressor 15, the switching valve 22 is fully opened to solve the problem.
[0060]
According to this control method, as shown in FIG. 6, during the start-up preparation, the control valve 22 flows into the R and F EVAs 10 and 12, but the pressure balance time through the refrigerated capillary tube 23 and the frozen capillary tube 24. And the inflow of the high-temperature refrigerant can be suppressed until immediately before the compressor 15 is started. Therefore, the internal temperature fluctuation can be suppressed as much as possible, and the power consumption can be reduced.
[0061]
As described above, when the preparation for starting the compressor 15 is in a fully opened state, the discharge pressure and the suction pressure of the compressor 15 are balanced at the time of starting, and starting in such a state is ideal and sufficient reliability is obtained. Can be secured.
[0062]
(4-2) First control method
A specific first control method of the above control method will be described based on the flowchart of FIG.
[0063]
In step 1, as shown in FIG. 3A, the refrigeration mode is performed, and the refrigeration mode is ended when the inside temperature of the R chamber 30 becomes a predetermined temperature or lower. Then, the process proceeds to Step 3.
[0064]
In step 2, as shown in FIG. 3B, the refrigeration mode is performed, and the refrigeration mode is terminated when the internal temperature of the F chamber 40 becomes a predetermined temperature or lower. Then, the process proceeds to Step 3.
[0065]
In step 3, as shown in FIG. 3C, the switching valve 22 is fully closed. As a result, a refrigerant recovery mode for retaining the refrigerant on the high pressure side is performed.
[0066]
In step 4, when the refrigerant recovery mode ends, the compressor 15 stops.
[0067]
If the internal temperature of the F chamber 40 or the R chamber 30 rises to the switching set temperature T1 of the switching valve 22 set lower than the compressor starting temperature T0 while the compressor 15 is stopped in step 5, the process proceeds to step 6. . For example, when the compressor starting temperature T0f of the F chamber 40 is −18 ° C., −16 ° C. is set as the switching set temperature T1f. When the compressor starting temperature T0r of the R chamber 40 is 3 ° C., 1 ° C. is set as the switching set temperature T1r.
[0068]
In step 6, as shown in FIG. 3D, the switching valve 22 is fully opened. As a result, the refrigerant flows into the R evaporator 10 and the F evaporator 12 and further flows into the low pressure side of the compressor 15. Therefore, the pressure balance between the high pressure side and the low pressure side of the compressor 15 can be made uniform, and the start-up preparation can be performed quickly.
[0069]
In step 7, when the internal temperature rises to the compressor start temperature T0, the process proceeds to step 8.
[0070]
In step 8, the compressor 15 is started. At this time, since the pressure balance between the high pressure side and the low pressure side of the compressor 15 is equal, sufficient reliability for starting can be obtained.
[0071]
As a modified example of the first control method, when the outside air temperature is lower than the reference temperature Tg, the switching set temperature T1 of the switching valve 22 is set higher. For example, when the reference temperature Tg of the outside air temperature is 10 ° C., the switching set temperature T 1 is reset from −16 ° C. to −17 ° C. when the outside air temperature is lower than 10 ° C.
[0072]
This is because when the outside air temperature is low, the pressure on the condenser 21 side is low, and the time required for pressure balance is shortened.
[0073]
Therefore, the inflow of the high-temperature refrigerant to the evaporator side can be suppressed for a long time until the compressor 15 is started.
[0074]
(4-3) Second control method
A specific second control method of the above control method will be described based on the flowchart of FIG.
[0075]
The second control method is the same as the first control method until the switching valve 22 is fully opened after the compressor 15 is stopped (steps 11 to 16).
[0076]
In step 17, when the internal temperature rises while the compressor 15 is stopped and rises to the compressor start temperature T0, the switching valve 22 is switched to the fully open state. On the other hand, it is measured that the startup preparation time K (for example, 2 minutes) elapses from the fully opened state.
[0077]
In step 18, the compressor 15 is started after the start preparation time K (2 minutes) has elapsed.
[0078]
As a result, even if a load is applied by opening / closing the door, even if the internal temperature rises before the pressure balance necessary for starting the compressor 15 is reached, the compressor 15 is only required for the pressure balance. The activation of the system becomes a standby state, and an unexpected situation due to the activation failure can be avoided.
[0079]
As a modified example of the second control method, when the outside air temperature is lower than the reference temperature Tg, the start preparation time K is set short. That is, when the outside air temperature is low, the pressure on the condenser 21 side is low, and the time required for pressure balance is shortened.
[0080]
Therefore, the high-temperature refrigerant inflow to the evaporator side can be suppressed for a long time until the compressor 15 is started.
[0081]
(5) Control method when the refrigerator is turned on
Next, a control method for operating the refrigerator when the power is turned on (for example, when an outlet is plugged in or when a power failure is recovered) in the refrigerator having the above configuration will be described with reference to FIG.
[0082]
In step 21, it is assumed that the power source is turned on after the outlet is plugged in or the power failure is recovered.
[0083]
In step 22, the control unit 64 fully opens the switching valve 22. As a result, the refrigerant flows into the R evaporator 10 and the F evaporator 12 and further flows into the low pressure side of the compressor 15. Therefore, the pressure balance between the high pressure side and the low pressure side of the compressor 15 becomes uniform, and the start-up preparation can be performed quickly.
[0084]
Then, it starts measuring the start preparation time K (for example, 2 minutes) from the time when the switching valve 22 is fully opened.
[0085]
In step 23, after the start preparation time K has elapsed, the compressor 15 is started in step 24.
[0086]
After starting the compressor 15, the process proceeds to the refrigeration mode in step 25 or the refrigeration mode in step 26.
[0087]
Thus, when the power is turned on, the compressor 15 is started after the pressure balance between the high pressure side and the low pressure side is performed, so that it is possible to avoid an unexpected situation due to the start failure. In addition, power consumption is reduced. Moreover, even if the capillary tube on one side is clogged with something, the starting failure of the compressor 15 can be prevented.
[0088]
(6) Control method when starting of compressor 15 fails
Although the compressor 15 can be reliably started by the above control methods, a restart control method after the compressor 15 has failed to start for some reason will be described with reference to the flowchart of FIG.
[0089]
In step 31, the control unit 64 starts the compressor 15. This activation is performed when the internal temperature rises or when the power is turned on as described in the above control method.
[0090]
In step 32, the control unit 64 detects that the compressor 15 has failed to start. As this detection method, detection is performed based on the current value of the drive current output from the inverter circuit to the brushless DC motor that drives the compressor 15. Since the start has failed, the control unit 64 proceeds to Step 33 in order to control the restart of the compressor 15.
[0091]
In step 33, the switching valve 22 is fully opened. As a result, the pressure balance between the high pressure side and the low pressure side of the compressor 15 is equalized, and the restart can be performed reliably. Then, the start preparation time K starts to be measured from this point.
[0092]
In step 34, when the start preparation time (for example, 2 minutes) has elapsed, the pressure balance between the high pressure side and the low pressure side of the compressor 15 becomes equal, and the process proceeds to step 35.
[0093]
In step 35, the compressor 15 is restarted, and the process proceeds to the refrigeration mode in step 36 or the refrigeration mode in step 37.
[0094]
In the case of the above control method, even if the startup of the compressor 15 fails, the switching valve 22 is fully opened when restarting to balance the high pressure side and the low pressure side of the compressor 15. Can be reliably restarted. In addition, power consumption is reduced. Moreover, even if the capillary tube on one side is clogged with something, the starting failure of the compressor 15 can be prevented.
[0095]
(7) Example of changing control method when starting compressor 15
In the above control method, when the compressor 15 is restarted, after the switching valve 22 is fully opened, the compressor 15 is started when the compressor starting temperature is reached or when the startup preparation time has elapsed. In this case, in each of the above embodiments, the switching valve 22 is switched to the R EVA 10 side or the F EVA 12 side since the refrigeration mode or the freezing mode is immediately shifted (see FIG. 3).
[0096]
In the control method of this modification, instead of the above control method, when the compressor 15 is started, the fully open state of the switching valve 22 is held for the fully open holding time.
[0097]
For example, after the compressor 15 is started, it is fully opened for a fully open holding time (for example, 1 minute), and after the balance between the high pressure side and the low pressure side is more reliably balanced, the refrigeration mode or the freezing mode is entered. It is to be migrated.
[0098]
As a result, the pressure balance is more reliably performed, and the compressor can be normally rotated. That is, power consumption is also reduced. Moreover, even if the capillary tube on one side is clogged with something, the starting failure of the compressor 15 can be prevented.
[0099]
(8) Control method when compressor 15 is stopped
In each of the above control methods, when the compressor 15 is stopped, the compressor 15 is stopped after the switching valve 22 is fully closed and the refrigerant is recovered regardless of whether the compressor 15 is in the refrigeration mode or the refrigeration mode. I am letting.
[0100]
An alternative stop control method will be described with reference to the time chart of FIG.
[0101]
In this stop control method, when the refrigeration mode ends, when the refrigeration mode ends, the switching valve 22 is fully closed to recover the refrigerant. Thereafter, the compressor 15 is stopped.
[0102]
On the other hand, when it is going to end in the refrigeration mode, as shown in FIG. 11, it does not end in the refrigeration mode. After reaching the freezer compartment cooling end temperature (for example, −20 ° C.), the switching valve 22 is fully closed to collect the refrigerant, and the compressor 15 is stopped.
[0103]
As described above, the reason why the refrigerant is recovered after the completion in the freezing mode is that the refrigerant can be recovered when the refrigerant is recovered immediately after the completion in the freezing mode.
[0104]
(Second embodiment)
A second embodiment will be described based on the refrigeration cycle of FIG.
[0105]
The difference between the second embodiment and the first embodiment is the structure of the refrigeration cycle.
[0106]
In the first embodiment, the R EVA 10 and the F EVA 12 are connected in parallel. However, in this embodiment, as shown in FIG. 12, the refrigerated capillary tube 23 and the R are connected to the first outlet of the switching valve 22. The evaporators 10 are sequentially connected, and a frozen capillary tube 24 is connected to the second outlet of the switching valve 22. Then, after connecting the outlet side of the R-evaporator 10 and the outlet side of the frozen capillary tube, the F-evaluator 12 is connected.
[0107]
Even in this second refrigeration cycle, as in the first refrigeration cycle, when the compressor 15 is stopped, the compressor 15 is stopped after the switching valve 22 is fully closed and the refrigerant is recovered. Let
[0108]
Further, when starting the compressor 15, the switching valve 22 is fully opened to balance the high pressure side and the low pressure side of the compressor 15, and then the compressor 15 is started.
[0109]
The specific control method is the same as the control method of the first embodiment.
[0110]
Also in the refrigeration cycle of the second embodiment, the start-up performance of the compressor 15 can be increased, the pressure balance can be accelerated, and the power consumption can be reduced.
[0111]
(Example of change)
In each of the above embodiments, a nonflammable refrigerant is used, but a flammable refrigerant (HC refrigerant) can be used instead. This is because, in each of the above embodiments, the amount of refrigerant can be reduced, so that even a flammable refrigerant is safe.
[0112]
【The invention's effect】
As described above, according to the present invention, since the compressor start-up preparation is performed with the switching valve fully opened, the pressure balance between the high-pressure side and the low-pressure side of the compressor can be quickly achieved, and the pressure difference of the start-up condition of the compressor is high The refrigerant can be prevented from flowing into the evaporator.
[0113]
In addition, it is possible to avoid an unexpected situation due to a failure in starting the compressor, and to reduce power consumption.
[0114]
Furthermore, the starting performance of the compressor can be improved, the pressure balance can be accelerated, and the power consumption can be reduced.
[Brief description of the drawings]
FIG. 1 is a longitudinal sectional view of a refrigerator according to a first embodiment of the present invention.
FIG. 2 is a configuration diagram of the refrigeration cycle.
FIG. 3 shows the refrigerant flow in the refrigeration cycle of the present embodiment, where (a) shows the refrigeration mode, (b) shows the refrigeration mode, (c) shows the fully closed state, and (d) shows the fully opened state. Is.
FIG. 4 shows the discharge pressure and suction pressure of a conventional compressor.
FIG. 5 also shows the discharge pressure and suction pressure of a conventional improved compressor.
FIG. 6 shows the discharge pressure and suction pressure of the compressor of this example.
FIG. 7 is a flowchart of a first control method of the present embodiment.
FIG. 8 is a flowchart of the same second control method.
FIG. 9 is a flowchart at power-on.
FIG. 10 is a flowchart in the case where the compressor fails to start and restarts.
FIG. 11 is a time chart of another control method when the compressor is stopped.
FIG. 12 is a configuration diagram of a second refrigeration cycle.
[Explanation of symbols]
1 Refrigerator body
2 Insulation partition wall
3 Refrigerated dividers
4 Refrigerated storage
5 Vegetable room
6 First freezer
7 Second freezer
8 Inner box
9 Insulated box
10 R Eva
11 R Fan
12 F EVA
13 F fan
14 Machine room
1 5 Compressor
16 Accumulator
17 Check valve
18 Cold air circuit
30 R room
Room 40 F

Claims (10)

Compressor, condenser and switching valve are connected in sequence,
The switching valve has a refrigeration cycle in which a refrigerator compartment evaporator and a freezer compartment evaporator are connected via respective throttle mechanisms,
In the refrigerator that alternately performs the refrigerating mode for cooling the refrigerating room and the refrigerating mode for cooling the refrigerating room by alternately switching the refrigerant flow path to the refrigerating room evaporator or the refrigerating room evaporator by the switching valve. ,
When the control means of the refrigerator stops the compressor,
The switching valve is fully closed, and the compressor is stopped after the refrigerant does not flow into either the refrigerator compartment evaporator or the freezer compartment evaporator,
When the control means starts the compressor,
Prior to starting the compressor, the switching valve is fully opened, and the compressor is started after the refrigerant flows into both the refrigerator compartment evaporator and the freezer compartment evaporator. refrigerator. When the control means starts the compressor,
When the internal temperature reaches the switching set temperature T1, the switching valve is fully opened, and when the internal temperature reaches the compressor starting temperature T0 (T0> T1), the compressor is started. The refrigerator according to claim 1. The control means includes
3. The refrigerator according to claim 2, wherein when the outside air temperature is lower than the reference temperature Tg, the switching set temperature T1 is set lower than the switching set temperature T1 when the outside air temperature is higher than the reference temperature Tg. When the control means starts the compressor,
When the internal temperature reaches the compressor start temperature T0, the switching valve is fully opened,
The refrigerator according to claim 1, wherein the compressor is started after the start preparation time K has elapsed since the fully opened state. The control means includes
5. The refrigerator according to claim 4, wherein when the outside air temperature is lower than the reference temperature Tg, the start preparation time K is set shorter than the start preparation time K when the outside air temperature is higher than the reference temperature Tg. Compressor, condenser and switching valve are connected in sequence,
The switching valve has a refrigeration cycle in which a refrigerator compartment evaporator and a freezer compartment evaporator are connected via respective throttle mechanisms,
In the refrigerator that alternately performs the refrigerating mode for cooling the refrigerating room and the refrigerating mode for cooling the refrigerating room by alternately switching the refrigerant flow path to the refrigerating room evaporator or the refrigerating room evaporator by the switching valve. ,
The refrigerator control means includes:
When the refrigerator is turned on to start the compressor,
The refrigerator is characterized in that the switching valve is fully opened during the start-up preparation time K, and the compressor is started after the refrigerant flows into both the refrigerator compartment evaporator and the freezer compartment evaporator. . Compressor, condenser and switching valve are connected in sequence,
The switching valve has a refrigeration cycle in which a refrigerator compartment evaporator and a freezer compartment evaporator are connected via respective throttle mechanisms,
In the refrigerator that alternately performs the refrigerating mode for cooling the refrigerating room and the refrigerating mode for cooling the refrigerating room by alternately switching the refrigerant flow path to the refrigerating room evaporator or the refrigerating room evaporator by the switching valve. ,
When the control means of the refrigerator detects that the compressor cannot be started and then restarts the compressor,
The switching valve is fully opened during the start-up preparation time K, and the compressor is restarted after the refrigerant flows into both the refrigerator compartment evaporator and the freezer compartment evaporator. refrigerator.   The refrigerator according to at least one of claims 1 to 7, wherein the control means maintains the fully open state of the switching valve for a fully open holding time from when the compressor is started. In the refrigeration cycle,
The refrigerating throttle mechanism and the refrigerating room evaporator are sequentially connected to the first outlet of the switching valve,
The freezing throttle mechanism and the freezer evaporator are connected in order to the second outlet of the switching valve,
The refrigerator according to at least one of claims 1 to 8, wherein the refrigerator compartment evaporator and the freezer compartment evaporator are connected to the compressor. In the refrigeration cycle,
The refrigerating throttle mechanism and the refrigerating room evaporator are sequentially connected to the first outlet of the switching valve,
The refrigeration throttle mechanism is connected to a second outlet of the switching valve;
The freezing throttle mechanism and the refrigerator compartment evaporator are connected to the freezer compartment evaporator,
The refrigerator according to at least one of claims 1 to 8, wherein the freezer evaporator is connected to the compressor.

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