JP2003028553A - Refrigerator - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a refrigerator capable of keeping a balance between a pressure on the high pressure side and a pressure on the low pressure side of a refrigerating cycle, necessary to starting of a compressor 15, in a short time and capable of effecting high efficient cooling. SOLUTION: In a refrigerating cycle where an R evaporator 10 and an F evaporator 12 are interconnected in parallel, in case the compressor 15 is stopped; a switching valve 22 is brought into a full closed state, and a refrigerant is recovered to the condenser 21 side. In case the compressor 15 is started, the switching valve 22 is brought into a full closed state, and a pressure balance is kept between the high pressure side and the low pressure side of the compressor 15.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a refrigerator in which a refrigerator and a freezer are provided with evaporators.

[0002]

2. Description of the Related Art Generally, a refrigerator constitutes a refrigeration cycle in which refrigerant discharged from a compressor passes through a condenser, a throttle mechanism (capillary tube), an evaporator, and then returns to the compressor.
One evaporator was cooling multiple rooms with different temperatures.

On the other hand, in recent years, an evaporator is arranged in each of a refrigerating room and a freezing room via a capillary tube having an arbitrary diameter, and a refrigerating mode for cooling the refrigerating room by switching a refrigerant flow path and a freezing for cooling the freezing room. A refrigerator has been proposed in which the modes are alternately cooled and the rotation speed of the compressor is varied to control the evaporation temperature suitable for the temperature zone of each room.

That is, the flow of the refrigerant discharged from the compressor is selectively controlled by the switching valve between the refrigerating capillary tube connected to the refrigerator compartment evaporator and the freezing capillary tube connected to the freezer compartment evaporator.

Further, an accumulator and a check valve are connected to the outlet of the freezer compartment evaporator, join the pipe connected from the outlet of the refrigerator compartment evaporator, and return to the compressor (Japanese Patent Application No. 11-17).
3729).

In the above refrigeration cycle, the following control method has also been proposed (Japanese Patent Application No. 2000-25).
4132).

That is, the switching valve is put into the refrigerating mode after a predetermined time or when the temperature inside the refrigerator reaches the set temperature after stopping the compressor after shutting off the refrigerant flow path by fully closing the switching valve. Is. Then, in order to efficiently perform each cooling mode, both the refrigerating-side refrigerant channel and the freezing-side refrigerant flow path are blocked before switching the cooling chamber to the refrigerating chamber side, and a refrigerant recovery mode for retaining the refrigerant on the high pressure side is performed. .

That is, by repeating the steps of the freezing mode, the fully closed state (refrigerant recovery mode) and the refrigerating mode, the necessary refrigerant is moved to the condenser side before the refrigerating mode, and the refrigerant delay in the refrigerating mode is eliminated. At the same time, the low-temperature refrigerant is retained in the freezing compartment by the action of the check valve utilizing the pressure difference between the refrigerating compartment and the freezing compartment.

[0009]

In the refrigerator having the refrigerating cycle as described above, each refrigerating chamber can be cooled at a temperature suitable for each evaporation temperature, so that a high refrigerating cycle efficiency can be obtained.

On the other hand, when the compressor is stopped, the switching valve is fully closed in order to prevent the high temperature refrigerant on the condenser side from flowing into the evaporator. And as a preparation for starting the compressor,
Before starting up, in order to balance the pressure on the low temperature side and the high temperature side, the fully closed state was switched to the refrigeration mode or the freezing mode.

However, such a control method has a limit in shortening the time required for pressure equilibrium required during 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 startup of the compressor, even if only one of the refrigeration side and the freezing side is opened as preparation for starting the compressor. There was a problem.

Further, there is a problem that the high temperature refrigerant flows into the evaporator side before the start-up, which adversely affects the reduction of power consumption.

In view of the above problems, the present invention can balance the pressures on 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 enables efficient cooling. It provides a refrigerator.

[0014]

According to a first aspect of the present invention, a compressor, a condenser, and a switching valve are sequentially connected, and the switching valve includes:
The refrigerator compartment evaporator and the refrigerator compartment evaporator each have a refrigeration cycle connected via a throttling mechanism, and the refrigerator compartment evaporator,
Alternatively, in the refrigerator in which the refrigerating mode for cooling the refrigerating chamber and the refrigerating mode for cooling the freezing chamber are alternately performed by alternately switching the refrigerant flow path to the freezing chamber evaporator by the switching valve, the control means of the refrigerator. When stopping the compressor, the switching valve is fully closed, and the compressor is stopped after the refrigerant does not flow into either the refrigerating compartment evaporator or the freezing compartment evaporator, When the control means starts the compressor, the switching valve is fully opened, and the compressor is started after the refrigerant flows to both the refrigerating compartment evaporator and the freezing compartment evaporator. It is a refrigerator characterized by that.

According to a second aspect of the present invention, when the control means starts the compressor, the internal temperature of the refrigerator is set to the switching set temperature T.
The refrigerator according to claim 1, wherein when the temperature reaches 1, the switching valve is not fully opened, and when the internal temperature reaches a compressor starting temperature T0 (T0> T1), the compressor is started. .

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.
3. The refrigerator according to claim 2, wherein is set to be lower than the switching set temperature T1 when the outside air temperature is higher than the reference temperature Tg.

According to a fourth aspect of the present invention, when the control means starts the compressor, when the internal temperature reaches the compressor starting temperature T0, the switching valve is not fully opened and is made fully open. The refrigerator according to claim 1, wherein the compressor is activated after a lapse of the activation preparation time K from time to time.

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.
The refrigerator according to claim 4, wherein the refrigerator is set to be shorter than a startup preparation time K when the outside air temperature is higher than the reference temperature Tg.

In a sixth aspect of the invention, a compressor, a condenser and a switching valve are sequentially connected, and a refrigerating compartment evaporator and a freezing compartment evaporator are respectively connected to the switching valve through throttling mechanisms. A refrigerating mode for cooling the refrigerating compartment and a refrigerating mode for cooling the refrigerating compartment by alternately switching the refrigerating compartment evaporator or the refrigerant flow path to the freezer compartment evaporator with the switching valve. In a refrigerator that alternately performs
When the power of the refrigerator is turned on and the compressor is started, the control means of the refrigerator keeps the switching valve fully open during the start preparation time K, and sets the refrigerator compartment evaporator and the freezer compartment evaporator. The refrigerator is characterized in that the compressor is started after the refrigerant flows to both of the containers.

According to a seventh aspect of the invention, a compressor, a condenser and a switching valve are connected in sequence, and a refrigerator compartment evaporator and a freezer compartment evaporator are respectively connected to the switching valve through throttling mechanisms. A refrigerating mode for cooling the refrigerating compartment and a refrigerating mode for cooling the refrigerating compartment by alternately switching the refrigerating compartment evaporator or the refrigerant flow path to the freezer compartment evaporator with the switching valve. In a refrigerator that alternately performs
When the control means of the refrigerator restarts the compressor after detecting that the compressor cannot be started,
The switching valve is fully opened during the startup preparation time K, and the compressor is restarted after the refrigerant flows to both the refrigerating compartment evaporator and the freezing compartment evaporator. It is a refrigerator.

The invention of claim 8 is characterized in that the control means holds the full open state of the switching valve for a full open holding time from the start of the compressor.
The refrigerator according to at least one of the above.

According to a ninth aspect of the present invention, in the refrigeration cycle, the refrigerating throttle mechanism and the refrigerating compartment evaporator are sequentially connected to the first outlet of the switching valve, and the second outlet of the switching valve is provided. 9. The freezing throttle mechanism and the freezer compartment evaporator are sequentially connected to each other, and the refrigerating compartment evaporator and the freezer compartment evaporator are connected to the compressor. The refrigerator according to at least one of the above.

According to a tenth aspect of the invention, in the refrigeration cycle, the refrigerating throttle mechanism and the refrigerating compartment evaporator are sequentially connected to the first outlet of the switching valve, and the second outlet of the switching valve is provided. The freezing throttle mechanism is connected to, the freezing throttle mechanism and the refrigerating compartment evaporator are connected to the freezing compartment evaporator, the freezing compartment evaporator is connected to the compressor, The refrigerator according to at least one of claims 1 to 8.

According to the first aspect of the invention, when the compressor is repeatedly operated to start and stop, the switching valve is fully closed to collect the high pressure refrigerant and then stop the compressor. After that, when the compressor is started, preparations for starting the compressor are made in the fully opened state to make the pressure balance between the high pressure side and the low pressure side uniform and then start.

As a result, it is possible to keep the fully closed state in which the high pressure refrigerant is prevented from flowing into the evaporator side for a long time while the compressor is stopped, and the high pressure side of the refrigeration cycle, which is a necessary condition for starting the compressor thereafter. The pressure balance on the low pressure side can be performed in a short time.

According to the second aspect of the present invention, while the compressor is stopped, the inflow of the high-pressure refrigerant into the evaporator is kept until the pressure difference between the high-pressure side and the low-pressure side reaches the pressure difference required for starting the compressor. The fully closed state can be maintained for a long time.

According to the third aspect of the present invention, the compressor can stand by until the pressure difference required for startup even if the outside air temperature fluctuates, so that the inflow of the high temperature refrigerant can be suppressed as much as possible and the compressor can be reliably operated. Can be started.

According to the fourth aspect of the present invention, even when the temperature inside the storage chamber suddenly rises due to opening and closing of the door or loading of the load while the compressor is stopped, and the compressor startup temperature is reached in a short time, the compressor Will wait until the pressure difference required for start-up, and the trouble that the start-up of the compressor fails due to the large pressure difference can be prevented.

According to the fifth aspect of the invention, even if the door is opened or closed or the load is applied, the compressor can stand by until the pressure difference required for starting, so that the inflow of the high temperature refrigerant can be suppressed as much as possible.

According to the invention of claim 6, after the power of the refrigerator is turned on, the switching valve is fully opened during the start preparation time K to balance the pressures of the high pressure side and the low pressure side of the refrigeration cycle. Thus, it is possible to reliably start the compressor.

According to the seventh aspect of the present invention, when the compressor fails to start and the compressor is restarted, the switching valve is fully opened during the start preparation time K, and the high pressure side of the refrigeration cycle is connected. Since the compressor is restarted after the pressure on the low pressure side is balanced, the restart can be reliably performed.

According to the eighth aspect of the present invention, the switching valve is fully opened for the full open holding time after the compressor is started, so that the pressure balance between the high pressure side and the low pressure side in the refrigeration cycle is surely achieved. Therefore, the steady rotation of the compressor thereafter can be smoothly performed.

[0033]

BEST MODE FOR CARRYING OUT THE INVENTION (First Embodiment) A first embodiment of the present invention will be specifically described below with reference to the drawings.

(1) Structure of refrigerator FIG. 1 is a cross-sectional view of a cold-cooled refrigerator according to this embodiment.

The refrigerator body 1 is formed of a heat insulating box 9 and an inner box 8. The heat insulation partition wall 2 divides the refrigerating temperature zone (hereinafter referred to as the R chamber) 30 and the freezing temperature zone (hereinafter referred to as the F chamber) 40 so that the cold air in these rooms is completely independent and the respective cold air is mixed. There is no structure.

The inside of the R chamber 30 is divided into the refrigerator chamber 4 and the vegetable chamber 5 by the refrigerator partition plate 3, and the inside of the F chamber 40 is the first.
It is composed of a freezing compartment 6 and a second freezing compartment 7, and each compartment has opening and closing doors 51 to 54, respectively.

On the back of the vegetable compartment 5, a refrigerator refrigerator (hereinafter,
An R evaporator 10 and a refrigerating compartment cooling fan (hereinafter referred to as R fan) 11 are arranged, and the R fan 11 is arbitrarily operated by temperature fluctuation in the refrigerator and opening / closing of a door. The back surface of the refrigerating chamber 4 serves as a cool air circulation path 18 for supplying cool air into the R chamber 30. The R fan 11 is inverter-controlled and has a variable speed.

Freezer compartment evaporator (hereinafter referred to as F evaporator) 12
A freezing compartment cooling fan (hereinafter referred to as F fan) 13 is disposed on the back wall of the first and second freezing compartments 6 and 7, and the first and second freezing compartments 6 and 7 are cooled by circulating cold air. It F
The fan 12 is inverter-controlled and has a variable speed.

A compressor 15 and a condenser 21 are arranged in the machine room 14 below the back wall of the refrigerator body 1. Further, it has a fan (hereinafter, referred to as C fan) 25 that radiates heat from the condenser 21. The C fan 25 has a variable speed under inverter control. The compressor 15 is a brushless D
It is driven by a C motor and its capacity is variable. The brushless DC motor has three phases, and its rotation is inverter-controlled by the drive current from the inverter circuit.

The defrosting heaters 60 and 62 are connected to the R
It is arranged below the 0, F Eva 12.

Further, on the upper rear portion of the refrigerator body 1, there is provided a control section 64 including a microcomputer for controlling the refrigerator. The controller 64 includes a brushless DC motor of the compressor 15, a brushless D that is a fan motor of the R fan 11, the F fan 12, and the C fan 25.
Inverter control of ON / OFF and rotation speed of the C motor. For example, in the case of the brushless DC motor of the compressor 15, the rotation speed signal is sent to the inverter circuit for control. It also controls the defrost heaters 60 and 62, and further controls the switching valve 22 described later.

(2) Structure of refrigeration cycle FIG. 2 shows a refrigerating cycle of a refrigerator.

The non-combustible refrigerant discharged from the compressor 15 is
After passing through the condenser 21, the refrigerant flow path is switched by the refrigerant switching mechanism of the switching valve 22 including the three-way valve.

The refrigerating capillary tube 23 and the R-eva 10 are sequentially connected to one outlet of the switching valve 22, and the freezing capillary tube 2 is connected to the other outlet of the switching valve 22.
4, the F-evaluator 12, and the accumulator 16 are sequentially connected.

The switching valve 22 is controlled by the control unit 64.
Can realize four states: a state of sending the refrigerant only to the refrigerating capillary tube 23, a state of sending the refrigerant only to the freezing capillary tube 24, a fully open state of sending the refrigerant to both, and a fully closed state of sending the refrigerant to neither.

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 joins the outlet pipe of the R-eva 10 and is connected to the suction side of the compressor 15. ing.

(3) Alternate Operation First, the normal internal temperature control operation in the refrigerator will be described.

The high-temperature refrigerant compressed and pressurized by the compressor 15 is radiated by the condenser 21, and the refrigerant discharged from the condenser 21 is switched by the switching valve 22.
Then, the R-evaporator 10 or the F-evaporator 12 is cooled, and the alternating operation of alternately performing the refrigerating mode and the freezing mode described below is performed.

(3-1) Refrigerating Mode When the temperature inside the R chamber 30 becomes higher than the set temperature, the refrigerating mode is performed.

As shown in FIG. 3A, in the refrigerating mode, the switching valve 22 is switched so that the refrigerating capillary tube 2 can be operated.
Refrigerant is caused to flow through the R 3 and evaporated in the R evaporator 10 to cool the R chamber 30. 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 does not flow into the F-eva 12 and re-condense.

(3-2) Freezing mode When the internal temperature of the F chamber 40 becomes higher than the set temperature, the freezing mode is performed.

In the freezing mode as shown in FIG. 3 (b),
The switching valve 22 is switched, the refrigerant flow path is switched so that the refrigerant flows through the freezing capillary tube 24, the F evaporator 12 evaporates, and returns to the compressor 15 through the accumulator 16 and the check valve 17.

Since these evaporators 10 and 12 are heat exchangers that exchange heat with air by forced convection, the R fan 11 in the refrigerating mode and the F fan 13 in the freezing mode are switched at the same time as the switching of the refrigerant flow paths. Operate to cool the interior.

(4) Control method at the time of stopping and starting the compressor 15 (4-1) Theoretical explanation of this control method In the refrigerating mode and the freezing mode as described above, the internal temperature of each room is both the compressor. If it is kept below the starting temperature of 15, the compressor 15 is stopped.

When the switching valve 22 is in the refrigerating mode or the refrigerating mode when the compressor 15 is stopped, the pressures on the high pressure side and the low pressure side in the refrigeration cycle are balanced in a short time, so that the compressor 15 thereafter can be reliably operated. Can be started. However, since the high-temperature refrigerant flows in from the condenser 21 side, the evaporator temperature rises, which affects fluctuations in the in-compartment temperature, resulting in an increase in power consumption.

Therefore, when the compressor 15 is stopped, the switching valve 22
Is fully closed to suppress the inflow of high-temperature refrigerant.

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.
There is a pressure difference of about MPa. Due to this pressure difference, sufficient reliability cannot be obtained to start the compressor 15, and it may not be possible to start it. That is, it is necessary to reduce the pressure difference in order for the compressor 15 to start.

Therefore, the prior art (Japanese Patent Application No. 2000-2
54132), as a preparation for starting the compressor 15, when the internal temperature reaches the starting temperature of the compressor 15, the switching valve 22 is set to the refrigerating mode. In this case, as shown in FIG. 5, the refrigerant on the condenser 21 side flows into the R-evaporator 10 via the refrigerating 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 refrigerating capillary tube 23, it takes a certain amount of time, and the inflow of the high-temperature refrigerant during this time causes the R evaporation 1
0 will lead to a temperature rise.

Therefore, in this control method, as shown in FIG. 3D, the switching valve 22 is prepared in preparation for starting the compressor 15.
It is solved by making the fully open state.

According to this control method, as shown in FIG. 6, during the preparation for start-up, the gas flows from the switching valve 22 into the R-evaporator 10 and the F-evaporator 12, but pressure is applied via the refrigerating capillary tube 23 and the freezing capillary tube 24. The balance time can be shortened, and the inflow of high-temperature refrigerant can be suppressed until immediately before the start of the compressor 15. Therefore, it is possible to suppress fluctuations in the internal temperature as much as possible and contribute to reduction in power consumption.

As described above, when the preparation for starting the compressor 15 is fully opened, 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. The reliability can be secured.

(4-2) First Control Method FIG. 7 shows a specific first control method of the above control method.
A description will be given based on the flowchart.

In step 1, as shown in FIG. 3A, the refrigerating mode is performed, and when the temperature inside the R chamber 30 becomes equal to or lower than the predetermined temperature, the refrigerating mode ends. Then, the process proceeds to step 3.

In step 2, as shown in FIG. 3B, the freezing mode is performed, and when the temperature inside the F chamber 40 becomes equal to or lower than the predetermined temperature, the freezing mode ends. Then, the process proceeds to step 3.

In step 3, as shown in FIG. 3C, the switching valve 22 is fully closed. Thereby, the refrigerant recovery mode in which the refrigerant stays on the high pressure side is performed.

In step 4, the compressor 15 stops when the refrigerant recovery mode ends.

In step 5, when 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, step Go to 6. For example, F room 4
When the compressor starting temperature T0f of 0 is -18 ° C, -1
6 ° 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.

In step 6, as shown in FIG. 3D, the switching valve 22 is fully opened. As a result, the refrigerant flows into the R-evaluator 10 and the F-evaluator 12, and the compressor 1
5 will flow into the low pressure side. Therefore, the compressor 15
The pressure balance between the high-pressure side and the low-pressure side becomes uniform and the startup preparation can be performed quickly.

At step 7, when the internal temperature rises to the compressor starting temperature T0, the process proceeds to step 8.

In step 8, the compressor 15 is started. At this time, the pressure balance between the high pressure side and the low pressure side of the compressor 15 is equal, so that sufficient reliability can be obtained for starting.

As a modification 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 high. For example, when the reference temperature Tg of the outside air temperature is 10 ° C., the outside air temperature is 1
When the temperature is lower than 0 ° C, the switching set temperature T1 is reset from -16 ° C to -17 ° C.

The reason for this is that when the outside air temperature is low, the condenser 2
This is because the pressure on the first side is low and the time required for pressure balance is short.

Therefore, the inflow of the high-temperature refrigerant to the evaporator side can be suppressed long until the compressor 15 is started.

(4-3) Second Control Method FIG. 8 shows a concrete second control method of the above control method.
A description will be given based on the flowchart.

In the second control method, after the compressor 15 is stopped,
The process until the switching valve 22 is fully opened is the same as the first control method (steps 11 to 16).

In step 17, when the temperature inside the refrigerator rises to the compressor starting temperature T0 while the compressor 15 is stopped, the switching valve 22 is switched to the fully open state. On the other hand, starting preparation time K (for example, 2 minutes) from the time when the fully opened state
Is measured.

In step 18, start preparation time K
After (2 minutes) has elapsed, the compressor 15 is started.

As a result, even if the load is applied by opening and closing the door, and even if the internal temperature of the refrigerator rises before the pressure balance required to start the compressor 15 is reached, only the time required for the pressure balance to be reached is achieved. The activation of the compressor 15 is in a standby state,
It is possible to avoid an unexpected situation due to a startup failure.

As a modification of the second control method, when the outside air temperature is lower than the reference temperature Tg, the start preparation time K is set to be 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.

Therefore, the inflow of high-temperature refrigerant to the evaporator side can be suppressed for a long time until the compressor 15 is activated.

(5) Control Method When Powering On Refrigerator Next, in the refrigerator having the above-mentioned configuration, when the power is turned on (for example, when the outlet is plugged in or when the power failure is restored), the refrigerator is operated. The control method will be described with reference to FIG.

In step 21, it is assumed that the power supply is turned on because the outlet is plugged in or the power failure is recovered.

At step 22, the control section 64 fully opens the switching valve 22. As a result, the refrigerant flows into the R-evaluator 10 and the F-evaluator 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 equal, and the startup preparation can be performed quickly.

Then, the measurement of the start preparation time K (for example, 2 minutes) is started from the time when the switching valve 22 is fully opened.

In step 23, the compressor 15 is started in step 24 after the start preparation time K has elapsed.

After activating the compressor 15, the process proceeds to the refrigerating mode in step 25 or the freezing mode in step 26.

As a result, when the power is turned on, the compressor 15 is started after the pressures on the high pressure side and the low pressure side are balanced, so that it is possible to avoid an unexpected situation due to a failure in starting. In addition, power consumption is also reduced. Further, even if the capillary tube on one side is clogged with something, it is possible to prevent the defective start of the compressor 15.

(6) Control Method When Startup of Compressor 15 Fails By the above control methods, the startup of the compressor 15 can be surely performed, but after the startup of the compressor 15 fails for some reason. The control method of the restart will be described based on the flowchart of FIG.

In step 31, the control section 64 starts the compressor 15. As described in the above control method, this activation is performed when the internal cold room temperature rises or when the power is turned on.

In step 32, the control section 64 detects that the activation of the compressor 15 has failed. As the 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-up has failed, the control unit 64 proceeds to step 33 to control the restart of the compressor 15.

At 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 becomes uniform, and the restart can be reliably performed. Then, from this time point, the start preparation time K is started to be measured.

In step 34, when the start preparation time (for example, 2 minutes) has elapsed, it is assumed that the pressure balance between the high pressure side and the low pressure side of the compressor 15 becomes equal, and step 35
Proceed to.

In step 35, the compressor 15 is restarted, and the process proceeds to the refrigerating mode in step 36 or the freezing mode in step 37.

In the above control method, even if the compressor 15 fails to start, the switching valve 22 is fully opened to restart the compressor 15 to balance the high pressure side and the low pressure side of the compressor 15. It is possible to reliably restart the compressor 15. In addition, power consumption is also reduced. Further, even if the capillary tube on one side is clogged with something, it is possible to prevent the start-up failure of the compressor 15.

(7) Example of Modification of Control Method When Starting Compressor 15 In the above control method, when the compressor 15 is restarted, the switching valve 22 is fully opened and then the compressor starting temperature is changed. Or the compressor 15 is started when the start preparation time has elapsed. In this case, in each of the above-described embodiments, the switching valve 22 is immediately switched to the refrigeration mode or the freezing mode.
Is switched to the R-evaluator 10 side or the F-evaluator 12 side (see FIG. 3).

In the control method of this modified example, instead of the above control method, when the compressor 15 is started, the switching valve 22 is kept in the fully opened state for the fully opened holding time.

For example, after the compressor 15 is started, the fully open state is maintained for a full open holding time (for example, 1 minute) to more reliably balance the high pressure side and the low pressure side, and then the refrigeration mode or It shifts to the freezing mode.

As a result, the pressure is balanced more reliably and the compressor can be rotated normally.
That is, power consumption is also reduced. Further, even if the capillary tube on one side is clogged with something, it is possible to prevent the defective start of the compressor 15.

(8) Control method when the compressor 15 is stopped In the above control methods, when the compressor 15 is stopped, either in the freezing mode or in the refrigerating mode,
After the switching valve 22 is fully closed to collect the refrigerant, the compressor 15 is stopped.

An alternative stop control method is shown in FIG.
It will be described based on the time chart of No. 1.

In this stop control method, when ending in the freezing mode, the switching valve 22 is fully closed when the freezing mode ends, and the refrigerant is recovered. Then, after that, the compressor 15 is stopped.

On the other hand, when the operation is to end in the refrigerating mode, it does not end in the refrigerating mode as shown in FIG. Is the freezing room cooling end temperature (for example, −
(20 ° C.), the switching valve 22 is fully closed to collect the refrigerant, and the compressor 15 is stopped.

The reason why the refrigerant is recovered in the freezing mode in this manner is that the refrigerant can be recovered when the refrigerant is recovered in the freezing mode and immediately thereafter.

(Second Embodiment) Regarding the second embodiment,
It demonstrates based on the refrigerating cycle of FIG.

The difference between the second embodiment and the first embodiment is the structure of the refrigeration cycle.

In the first embodiment, R-evaluator 10 and F-evaluator 1 are used.
In the present embodiment, as shown in FIG. 12, the refrigerating capillary tube 23 and the R-eva 10 are sequentially connected to the first outlet of the switching valve 22, and the second valve of the switching valve 22 is connected. A frozen capillary tube 24 is connected to the outlet of the. Then, after connecting the outlet side of the R evaporator 10 and the outlet side of the frozen capillary tube, the F evaporator 12 is connected.

Even in this second refrigeration cycle,
Similar to the refrigeration cycle of (1), when the compressor 15 is stopped, the switching valve 22 is fully closed to collect the refrigerant, and then the compressor 15 is stopped.

When activating 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.

The specific control method is the same as the control method of the first embodiment.

Also in the refrigeration cycle of the second embodiment,
The starting performance of the compressor 15 can be improved, the pressure balance can be improved, and the power consumption can be reduced.

(Modification) In each of the above embodiments, a nonflammable refrigerant was used, but a flammable refrigerant (HC refrigerant) may be used instead. This is because in each of the above-described embodiments, the amount of the refrigerant can be reduced, so that a flammable refrigerant is safe.

[0112]

As described above, according to the present invention,
Since the preparation for starting the compressor is performed with the switching valve fully open, the pressure on the high-pressure side and the low-pressure side of the compressor can be quickly balanced, and the high-temperature refrigerant can be prevented from flowing into the evaporator up to the pressure difference of the starting conditions of the compressor. You can

Further, it is possible to avoid an unexpected situation due to a failure in starting the compressor, and it is possible to reduce power consumption.

Furthermore, the starting performance of the compressor can be improved, the pressure balance can be improved, and the power consumption can be reduced.

[Brief description of drawings]

FIG. 1 is a vertical sectional view of a refrigerator according to a first embodiment of the present invention.

FIG. 2 is a configuration diagram of a refrigeration cycle of the same.

FIG. 3 shows a flow of a refrigerant in a refrigeration cycle of the present embodiment, (a) shows a refrigerating mode, (b) shows a refrigerating mode, (c) shows a fully closed state, and (d) shows a fully opened state. It is a thing.

FIG. 4 shows discharge pressure and suction pressure of a conventional compressor.

FIG. 5 is a view showing discharge pressure and suction pressure of the conventional improved compressor.

FIG. 6 shows the discharge pressure and the suction pressure of the compressor of this embodiment.

FIG. 7 is a flow chart of a first control method of this embodiment.

FIG. 8 is a flow chart of the second control method of the same.

FIG. 9 is a flowchart when the power is turned on.

FIG. 10 is a flowchart in the case where the compressor fails to start and is restarted.

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 heat insulation partition wall 3 refrigerated dividers 4 Cold storage 5 vegetable room 6 First freezing room 7 Second freezing room 8 inner boxes 9 Insulation 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 circulation 30 R room 40F room

   ─────────────────────────────────────────────────── ─── Continued front page    (72) Inventor Yoshifumi Noguchi             No. 6 Ota-Toshiba-cho, Ibaraki City, Osaka Prefecture Stock Association             Company Toshiba Osaka factory F term (reference) 3L045 AA04 BA01 CA02 EA01 MA01                       MA12 PA01 PA02 PA04 PA05

Claims (10)

[Claims] 1. A compressor, a condenser, and a switching valve are sequentially connected, and the switching valve has a refrigeration cycle in which a refrigerating compartment evaporator and a freezing compartment evaporator are respectively connected through a throttle mechanism. A refrigerator that alternately performs a refrigerating mode for cooling the refrigerating compartment and a refrigerating compartment by alternately switching the refrigerant passage to the refrigerating compartment evaporator or the freezer compartment evaporator by the switching valve. In the case where the control means of the refrigerator stops the compressor, after the switching valve is fully closed, the refrigerant does not flow into either the refrigerator compartment evaporator or the freezer compartment evaporator. When the compressor is stopped and the control means starts the compressor, the switching valve is fully opened so that the refrigerant flows in both the refrigerator compartment evaporator and the freezer compartment evaporator. From the compressor Refrigerator, characterized in that the motion. 2. When the control means starts the compressor, when the internal temperature reaches the switching set temperature T1, the switching valve is not fully opened, and the internal temperature is the compressor starting temperature T1.
The refrigerator according to claim 1, wherein the compressor is started when 0 (T0> T1) is reached. 3. The control means, when the outside air temperature is lower than a reference temperature Tg, the switching set temperature T
The refrigerator according to claim 2, wherein 1 is set to be lower than a switching set temperature T1 when the outside air temperature is higher than the reference temperature Tg. 4. When the control means starts the compressor, when the internal temperature reaches the compressor starting temperature T0, the switching valve is not fully opened, and the start preparation time is set from the time when the controller is fully opened. The refrigerator according to claim 1, wherein the compressor is started after K has elapsed. 5. The start-up preparation time K when the outside air temperature is lower than a reference temperature Tg.
Is set to be shorter than the startup preparation time K when the outside air temperature is higher than the reference temperature Tg.
Refrigerator described. 6. A compressor, a condenser, and a switching valve are sequentially connected, and the switching valve has a refrigeration cycle in which a refrigerating compartment evaporator and a freezing compartment evaporator are respectively connected through a throttling mechanism. A refrigerator that alternately performs a refrigerating mode for cooling the refrigerating chamber and a refrigerating chamber by alternately switching the refrigerant passage to the refrigerating chamber evaporator by the switching valve. In the case where the refrigerator is turned on to start the compressor, the control means of the refrigerator keeps the switching valve fully open during a start preparation time K to set the refrigerator compartment evaporator and the freezer. A refrigerator characterized in that the compressor is started after the refrigerant flows to both of the room evaporators. 7. A compressor, a condenser, and a switching valve are sequentially connected, and the switching valve has a refrigeration cycle in which a refrigerating compartment evaporator and a freezing compartment evaporator are respectively connected through a throttling mechanism. A refrigerator that alternately performs a refrigerating mode for cooling the refrigerating chamber and a refrigerating chamber by alternately switching the refrigerant passage to the refrigerating chamber evaporator by the switching valve. In the case where 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 preparation time K, and A refrigerator characterized in that the compressor is restarted after the refrigerant flows in both the refrigerator compartment evaporator and the freezer compartment evaporator. 8. The at least one of claims 1 to 7, wherein the control means holds the full open state of the switching valve for a full open holding time after starting the compressor. Refrigerator. 9. In the refrigeration cycle, the refrigeration throttle mechanism and the refrigeration compartment evaporator are sequentially connected to a first outlet of the switching valve, and the refrigeration throttle is connected to a second outlet of the switching valve. 9. A mechanism and the freezer compartment evaporator are sequentially connected, and the refrigerating compartment evaporator and the freezer compartment evaporator are connected to the compressor, at least one of claims 1 to 8. Refrigerator described in. 10. In the refrigeration cycle, the refrigerating throttle mechanism and the refrigerating compartment evaporator are sequentially connected to a first outlet of the switching valve, and the refrigerating throttle is connected to a second outlet of the switching valve. A mechanism is connected, the freezing throttle mechanism and the refrigerating compartment evaporator are connected to the freezing compartment evaporator, and the freezing compartment evaporator is connected to the compressor. The refrigerator according to at least one of item 8.