JPH07109342B2 - refrigerator - Google Patents

Description

TECHNICAL FIELD The present invention relates to improvements in refrigerators.

(Prior Art) Conventionally, in this type of refrigerator, an air flow circulation passage is formed between an inner wall of a heat insulating box constituting the refrigerator body and an outer wall of a storage box arranged in the heat insulating box, and An air blower fan and a refrigeration cycle evaporator are installed in the air flow circulation passage, and when defrosting, the high-temperature and high-pressure compressed refrigerant discharged from the refrigeration cycle compressor is allowed to directly flow into the evaporator through a hot gas valve. Along with heating the evaporator, the air heated by this evaporator is circulated in the air flow circulation passage as an air flow by a blower fan to raise the temperature of the storage box, and the frost grown on both the surface of the evaporator and the inner wall of the storage box. There is one that is designed to be defrosted at the same time.

(Problems to be Solved by the Invention) In such a configuration, since frost growing on the surface of the evaporator is larger than frost growing on the inner wall of the storage box, the defrosting end temperature of the evaporator is Better
The defrosting temperature of the storage box is set to 5-10 ℃ higher than 0.1-1 ℃. Therefore, in the simultaneous defrosting process as described above, heating of the evaporator for defrosting the evaporator must be continued even after the defrosting of the storage box is completed.

However, since the storage box is cooled by the stored heat of the objects to be cooled in the storage box, the temperature of the circulating air flow is unlikely to rise despite the heating of the evaporator. Therefore, it takes a long time to finish defrosting the evaporator and the entire storage box. This becomes more remarkable as the number of objects to be refrigerated in the storage box increases. As a result, the defrosting time of the evaporator after the defrosting of the storage is extended, and the temperature of the object to be refrigerated rises conversely, causing deterioration and discoloration. Further, when the ambient temperature is low, the heating effect of the compressed refrigerant flowing through the hot gas valve into the evaporator is lowered, and the defrosting time becomes extremely long. It should be noted that the above also occurs when a heater is used instead of the hot gas valve and the evaporator is heated by this heater.

Therefore, in order to deal with the above, the present invention provides a refrigerator in which an airflow circulation passage between a heat insulating box that constitutes the refrigerator main body and a storage box arranged in the heat insulating box is provided. It is intended to effectively realize defrosting of both the evaporator and the storage box.

(Means for Solving the Problem) In solving the above problems, the configuration of the present invention has a storage box disposed in a heat insulation box, and air flow circulation is provided between an inner wall of the heat insulation box and an outer wall of the storage box. A refrigerator body having a passage formed therein, a compression means for compressing an inflowing refrigerant into a high temperature and high pressure compressed refrigerant in an operating state, a refrigerant state conversion means for condensing the compressed refrigerant and converting it into a low temperature and low pressure refrigerant, and the air flow circulation passage. An evaporating means that is disposed inside and exhibits a cooling function in response to the inflow of the low-temperature low-pressure refrigerant, and that causes the inflowing refrigerant to flow into the compression means; and, when opening, the compressed refrigerant from the compression means heats the evaporation means. Therefore, a refrigeration cycle including valve means for directly flowing into the evaporation means, and a fan hand disposed in the air flow circulation passage for circulating the air flow from the evaporation means through the air flow circulation passage according to the operation. And the temperature inside the storage box is the lower limit of the predetermined cooling temperature range (or,
When the temperature of the evaporating means rises to a predetermined evaporating means defrosting ending temperature, the first temperature detecting means is set to the first (or second) detection state when the upper limit value) is reached, and this is detected. Controlled so as to drive the compression means in the second detection state of the second temperature detection means for detecting and the first temperature detection means and stop the compression means in the first detection state of the first temperature detection means. The first control means and the evaporation means for a predetermined cooling time to be in the first closed state and to close the valve means,
Timer switch means that is in a second closed state when the cooling time has elapsed and opens the valve means, and that is in the first closed state when a predetermined storage defrost time has elapsed after the detection by the second temperature detection means, When the timer switch means is in the second closing state when the second temperature detecting means is not detected, the fan means is stopped, and the fan means is operated under the detection of the second temperature detecting means. And a second control means for controlling.

(Operation) With the above configuration of the present invention, when the timer switch means is in the first closing state and the valve means is closed during the predetermined cooling time, the first control means is The compression means is controlled to stop or operate in the first or second detection state of the first temperature detection means. For this reason, the food to be refrigerated in the storage is refrigerated while being maintained at a temperature within the cooling temperature range based on the cooling function of the evaporation means under the selective operation of the compression means of the refrigeration cycle.

When the cooling time elapses, the timer switch means sets the second
When in the closed state, the valve means is opened. At this time,
The compression means is selectively operated under the control of the first control means in cooperation with the first temperature detection means. Further, the second control means controls to stop the fan means under the detection of the second temperature detection means and in the second closed state of the timer switch means. Therefore, the evaporation means is heated by the thermal energy of the compressed refrigerant applied to the evaporation means from the compression means via the valve means while the fan means is stopped. As a result, defrosting of the evaporation means is started.

Then, when the second temperature detecting means detects an increase in the temperature of the evaporating means to the evaporating means defrosting end temperature as the defrosting of the evaporating means progresses, the second control means causes the valve means to operate. The fan means is controlled to operate on the basis of the opening and the operation of the compression means. For this reason, the heating air from the evaporation means is heated as the air flow under the action of the fan means under the heating of the evaporation means by the compressed refrigerant from the compression means to the evaporation means via the valve means. It circulates in the circulation circuit. As a result, defrosting of the storage box is started. When the storage defrosting time has elapsed, the timer switch means enters the first closing state and the defrosting of the storage box ends.

(Effect) Therefore, even if frost adheres and grows on the evaporation means and the storage during the cooling time, as described above, the defrosting of the evaporation means is performed by the compression means while the fan means is stopped. From the thermal energy of the compressed refrigerant applied to the evaporation means via the valve means, while defrosting the storage box, the heat of the compressed refrigerant to the evaporation means after completion of the defrosting of the evaporation means. Since both energy and the blowing action of the fan means to the air heated by this heat energy are used, the defrosting of both the evaporation means and the storage box provides the heat energy necessary for melting each frost. It is always done with sufficient security. As a result, both defrosting of the evaporation means and the storage box can be efficiently and accurately performed in a short time.
In such a case, since the evaporation means is defrosted as described above, when the ambient temperature decreases, such as in the winter, despite the decrease in the effect of the thermal energy of the compressed refrigerant, the compressed refrigerant for heating the evaporation means is used. The thermal energy of is effectively used. As a result, the defrosting of the evaporation means can be smoothly performed.

Further, in the present invention, instead of the valve means, a heating means is adopted, and when the heating means is arranged in the vicinity of the evaporation means so as to heat the evaporation means by its heat generating action, As described above, the same action and effect as described above can be achieved by the heat generating action of the heating unit instead of the thermal energy of the compressed refrigerant applied from the compression unit to the evaporation unit via the valve unit.

Further, in the present invention described above, when the defrosting end temperature of the evaporation means is set to be higher than the defrosting end temperature of the storage box, the evaporation means until the defrosting of the evaporation means ends. In the subsequent defrosting of the storage box, the temperature of the circulating air flow blown by the fan means rapidly rises because the defrosting heat storage energy is increased. Therefore, even when the objects to be refrigerated in the storage box have many objects to be refrigerated and it is difficult to defrost the stored heat, the defrosting of the storage box can be appropriately performed in a short time.

Further, in solving the above-mentioned problems, the configuration of the present invention has a storage box disposed in a heat insulation box, and an air flow circulation passage is formed between an inner wall of the heat insulation box and an outer wall of the storage box. A refrigerator body, a compression unit that compresses an inflowing refrigerant into a high-temperature high-pressure compressed refrigerant in an operating state, a refrigerant state conversion unit that condenses the compressed refrigerant into a low-temperature low-pressure refrigerant, and is arranged in the airflow circulation passage. Evaporating means that exerts a cooling function in response to the inflow of the low-temperature low-pressure refrigerant and causes the inflowing refrigerant to flow into the compression means, and the compressed refrigerant from the compression means at the time of opening directly to the evaporation means to heat the evaporation means. A refrigeration cycle consisting of valve means for inflowing, fan means arranged in the air flow circulation passage for circulating the air flow from the evaporation means through the air flow circulation passage in response to operation,
A first temperature detecting means for detecting when a temperature in the center of the storage box reaches a lower limit value (or an upper limit value) of a predetermined cooling temperature range to be in a first (or second) detection state; Second temperature detecting means for detecting when the temperature of the evaporating means has risen to a predetermined defrosting ending temperature of the evaporating means, and for detecting when the temperature of the inner surface of the peripheral wall of the storage box is lower (or higher) than the predetermined inner surface temperature. Then, the third temperature detecting means in the first (or second) detecting state and the first detecting state of the first temperature detecting means by driving the compressing means in the second detecting state of the first temperature detecting means. For controlling to stop the compression means at
A control means, a timer switch means for closing the valve means in a first closed state for a predetermined cooling time by the evaporation means, and a second closed state for opening the valve means after the cooling time elapses; When the timer switch means is in the second closing state without the second temperature detecting means being detected, the fan means is stopped, and the fan means is operated under the detection of the second temperature detecting means. Control so as to maintain (or release) the open state of the valve means and the control state of the second control means in the first (or second) detection state of the second control means and the third temperature detection means. And a third control means for doing so.

With such a configuration, when the defrosting of the storage box is performed after the defrosting of the evaporating means is completed in the same manner as described above, the defrosting of the storage box is performed when the second detection state of the third temperature detecting means is established. It will end. Therefore, when there is a change in the growth amount of frost in the storage box, the defrosting time of the storage box expands and contracts according to the amount of growth of frost described above, and the refrigerated quality of the food to be refrigerated is good. The next cooling by the refrigeration cycle is performed while maintaining the above.

Further, in the present invention, instead of the valve means, a heating means is adopted, and when the heating means is arranged in the vicinity of the evaporation means in order to heat the evaporation means by its heat generating action, As described above, by utilizing the heat generating action of the heating device instead of the thermal energy of the compressed refrigerant applied from the compression device to the evaporation device via the valve device, the same action and effect as described above can be achieved in the defrosting of the storage box.

(Embodiment) Hereinafter, a first embodiment of the present invention will be described with reference to the drawings. FIGS. 1 to 5 show an example of a refrigerator to which the present invention is applied. 2 to 4), a refrigeration cycle R (see FIG. 5), and a sequence control circuit S (see FIG. 1).
The freezer body B has a heat insulating box 10, and this heat insulating box 10
Accommodates the inner box 12 inside the outer box 11, and
A heat insulating layer 13 is formed by uniformly filling a heat insulating material such as urethane foam between the inner wall of 11 and the outer wall of the inner box 12. A pair of left and right openings 14 and 15 are formed on the front wall of the heat insulating box 10 as shown in FIG. 4, and the heat insulating doors 16 and 17 are provided in the openings 14 and 15, respectively. Each is openable and closable.

The storage box 20 is for storing the objects to be refrigerated, and the storage box 20 is made of a heat conductive metal plate material such as stainless steel and is disposed in the heat insulation box 10. Also, storage box 20
An opening 21a is formed in the front wall 21 of the storage box 20 to store the object to be refrigerated. Then, in the storage box 20, the outer peripheral edge portion of the opening portion 21a is fixed to the outer peripheral edge portion of the inner surface of the front wall of the heat insulating box 10 so that the opening portion 21a faces both the opening portions 14 and 15 of the heat insulating box 10. The storage box 20 has an upper wall 22, a bottom wall 23, left and right side walls 24 and 25, a rear wall 26, and an inner wall of the heat insulating box 10 opposed to the upper wall 22, the bottom wall 23, the left and right side walls 24, 25, and an inner wall of the heat insulating box 10. Has been done.

The refrigeration cycle R has an evaporator 30 as shown in FIGS. 3 to 5, and the evaporator 30 together with the blower fan 40 includes a right wall 25 of the storage box 20 and a heat insulating box 10 facing the right wall 25. It is arranged between the opposing wall. Blower fan 40
Is disposed above the evaporator 30, and the blower fan 40 has a cover 3 depending on the operation of the fan motor 40a.
The air is blown toward the space between the upper wall 22 of the storage box 20 and the upper wall of the heat insulating box 10 through the opening 31a of 1. The evaporator 30 is
The inflowing refrigerant cools the inflowing airflow that is the medium to be cooled and causes it to flow toward the blower fan 40. The cover 31 is
The heat insulating box (10) extends downward from the upper wall and covers the evaporator (30).

Each of the remaining components of the refrigeration cycle R is housed in an auxiliary box 10a attached to the right wall of the heat insulating box 10, and the compressor 50 is connected to the piping according to the operation of the compressor motor 50a (see FIG. 1). The refrigerant is sucked and compressed from the evaporator 30 via P _{1 and applied} to the condenser 60 as high-temperature and high-pressure compressed refrigerant. The condenser 60 condenses the compressed refrigerant under the air-cooling action of the air-cooling fan 70 and supplies it to the dryer 80 as a condensed refrigerant through the pipe P3. The air-cooled fan 70 has its fan motor
Delivers air-cooling according to the operation of 70a. The capillary tube 90 receives the dehumidified condensed refrigerant from the dryer 80, and supplies it to the evaporator 30 as a low-temperature low-pressure refrigerant through the pipe P4. The hot gas valve 100, which is a normally-closed solenoid valve, is opened from the compressor 50 to the upstream portion of the pipe P2 and the pipe P5 when the hot gas valve 100 is opened.
A compressed refrigerant is applied through the pipe and the compressed refrigerant is applied to the evaporator 30 through the downstream portions of the pipe P6 and the pipe P4.

The sequence control circuit S has a pair of common conductors L1 and L2, and the common conductor L1 is connected to one end of the commercial power supply Ps via a fuse F. Also, the common conductor L2
Is connected to the other end of the commercial power supply Ps.
The normally open relay switch X is connected to the common conductor L1 at one end thereof, and the other end of the relay switch X is connected to the common conductor L2 via the compressor motor 50a.
The other end of the relay switch X is connected to the fixed contact 111 of the cam timer 110 via the fan motor 70a. Thus, the relay switch X connects the compressor motor 50a and the fan motor 70a to the common conductor L1 only when it is selectively closed. The relay switch X constitutes a relay together with the relay coil Rx, and the relay switch X is closed only when the relay coil Rx is excited.

The cam timer 110 includes a motor 110a and fixed contacts 111 and 112.
And a switching contact 113 which is selectively switched on to each of the fixed contacts 111 and 112. Then,
The cam timer 110 starts timing of a predetermined cooling time in the same manner as the rotation of the motor 110a when the switching contact 113 is turned on to the fixed contact 111, and fixes the switching contact 113 at the same time when the timing of the predetermined cooling time ends. Switch to contact 112. After that,
When the motor 110a restarts after the stop, it starts to measure the predetermined defrosting time of the storage box, and at the end of this time, the switching contact 11
Switch 3 to fixed contact 111. However, one end of the motor 110a is connected to the common conductor L1 via the normally closed relay switch Y1, and the other end of the motor 110a is connected to the common conductor L2. Further, the fixed contact 112 is connected to the common conductor L1 via the hot gas valve 100, and the relay coil Ry
And a thermoswitch Th1 through a series circuit connected to the common conductor L1. Further, the switching contact 113 is connected to the common conducting wire L2.

As shown in FIG. 3, the normally open type thermoswitch Th1 is attached to the end face of the evaporator 30. The thermoswitch Th1 is a thermostat Th1 that has a predetermined defrosting end temperature T of the temperature of the evaporator 30.
It opens when the temperature rises to b and closes when the temperature of the evaporator 30 drops to a predetermined temperature Ta (<Tb). Relay coil Ry
Forms a relay together with the relay switch Y1 and the normally open relay switch Y2, and the relay coil Ry opens the relay switch Y1 and closes the relay switch Y2 when selectively energized. Also, relay switch Y1
The fan motor 40a is connected between and the common conductor L2.

The thermo switch Th2, as shown in FIG.
This thermo switch Th is arranged in the center of the
2 is closed when the temperature in the storage box 20 (hereinafter, referred to as internal temperature T) rises to a predetermined upper limit set temperature Tu (<Tb). In addition, after this closing, the internal temperature T is a predetermined lower limit set temperature Tl.
When it decreases to (<Ta), the thermo switch Th2 opens. However, the thermoswitch Th2 is connected to the common conductor L1 at one end thereof, and the other end of the thermoswitch Th2 is connected to the common conductor L2 via the relay coil Rx and is commonly connected via the relay switch Y2. Connected to conductor L1. The antifreezing heater H1 is attached to the dew pan provided directly below the evaporator 30 in the storage case 20, and the heater H1 heats the dew pan by its heat generating action. The dew condensation prevention heater H2 is installed in both openings of the heat insulation box 10.
The heater H2 is attached to the inner surface portion of the front wall between 14 and 15, and the heater H2 plays a role of preventing dew condensation on the front wall of the heat insulating box 10 by its heat generating action. However, each of the heaters H1 and H2 is connected between both common conductors L1 and L2. The dew tray collects the dropped water droplets from the evaporator 30 and discharges them to the outside of the refrigerator body B.

In the first embodiment constructed as described above, since the internal compartment temperature T is considerably high, it is assumed that the thermoswitch Th1 is open and the thermoswitch Th2 is closed. In such a state, at the time t = t1 (see FIG. 6), the commercial power supply Ps is connected via the fuse F between both common conductors L1 and L2.
When an alternating voltage is applied from the relay coil Rx, the relay coil Rx is excited by the alternating voltage via the thermoswitch Th2 to close the relay switch X (see FIG. 6). Then, the compressor motor 50a passes through the relay switch X and the common wire L1,
The fan motor 70a operates by receiving an AC voltage from L2, and while the fan motor 70a is closing the switching contact 113 of the cam timer 110 to the fixed contact 111 (hereinafter referred to as the first closing), the common wire L
It operates by receiving an AC voltage from between L1 and L2 (see Fig. 6).
Further, the motor 110a of the cam timer 110 is connected to the relay switch Y1.
The AC motor receives the AC voltage from both common conductors L1 and L2 via the switch and starts counting the predetermined cooling time, and the fan motor 40a receives the AC voltage from both common conductors L1 and L2 via the relay switch Y1. It operates (see Fig. 6). Both heaters H1 and H2 exert their heat generating action.

Then, the compressor 50 is driven by the compressor motor 50a, sucks and compresses the refrigerant from the evaporator 30 through the pipe P1, and causes the refrigerant to flow into the condenser 60 through the pipe P2 as high-temperature and high-pressure compressed refrigerant. Then, the condenser 60 condenses the inflowing compressed refrigerant in accordance with the air-cooling action accompanying the operation of the fan motor 70a of the air-cooling fan 70, and dries it as a condensed refrigerant.
Through capillary tube 90. Then,
This capillary tube 90 flows into the evaporator 30 through the pipe P4 as a low-temperature low-pressure refrigerant of the inflowing condensed refrigerant. Therefore, the evaporator 30 starts cooling the air in the vicinity thereof according to the inflowing refrigerant.

At this time, the blower fan 40 exerts a blowing action according to the operation of the fan motor 40a, and the cooling air by the evaporator 30 is used as a cooling air flow to form a space between the upper wall of the heat insulating box 10 and the upper wall 22 of the storage box 20. Blow to. Therefore, the cooling air flow flows leftward (rightward in FIG. 3) along the upper wall 22 and the back wall 26 of the storage box 20, and the left wall 24 of the storage box 20 and the heat insulating box 10
Flows downwards along the left wall of the storage box, and then the bottom wall 23 of the storage box 20.
And along the bottom wall of the insulation box 10 to the right (to the left in Fig. 3)
And flows back to the evaporator 30 so as to be cooled by the evaporator 30. Thereafter, the same cooling air flow as described above is repeatedly circulated through the air flow circulation passage to gradually lower the temperature in the storage case 20. This is a storage box
It means the start of refrigeration of refrigerated items within 20.

When the internal temperature T in the storage box 20 decreases and reaches the lower limit set temperature Tl (see FIG. 6), the thermoswitch Th2 is opened. Then, the relay coil Rx is demagnetized by the opening of the thermoswitch Th2 to open the relay switch X. Therefore, the compressor 50 stops the compression action by stopping the compressor motor 50a, and the air cooling fan 70 stops the air cooling action by stopping the fan motor 70a. However, the blowing of the blowing fan 40 is maintained as it is. After that, the temperature T in the refrigerator gradually rises due to heat entering the storage box 20 from the outside of the refrigerator body B, heat generation of the fan motor 40a, or heat radiation from the food to be refrigerated in the storage box 20. When the upper limit set temperature Tu (see FIG. 6) is reached, the thermo switch Th2 is closed, the relay coil Rx is excited and the relay switch X is closed, and the compressor 50 and the air cooling fan 70 are closed.
Start together with the operation of the blower fan 40. Therefore, the cooling by the refrigeration cycle R is restarted. Thereafter, by repeating the above-described operation, the temperature T in the refrigerator is maintained between Tu and Tl as shown by the curve L in FIG. Refrigeration progresses, and in the course of such progress, frost gradually grows in layers on the surface of the evaporator 30. Further, when the internal temperature T is 0 ° C. or lower, the wall surface temperature of the storage box 20 is also 0 ° C. or lower, and dew freezes on the inner wall surface of the storage box 20 to become frost, which gradually grows in layers. It should be noted that the occurrence of dew condensation on the front wall of the storage box 20 is prevented by the heater H2.

Then, at t = t2 (see FIG. 6), when the cam timer 110 makes the switching contact 113 into the fixed contact 112 (hereinafter referred to as the second making) due to the lapse of the predetermined cooling time, the air-cooling fan 70 is turned on. When the fan motor 70a is stopped, the fan motor 70a is stopped and the hot gas valve 100 is opened. This means that the refrigeration cycle R shifts from the cooling cycle to the defrosting cycle. At this time, since the temperature of the evaporator 30 is sufficiently low, the thermoswitch Th1 is in the closed state. Therefore, the relay coil Ry is excited to open the relay switch Y1 and close the relay switch Y2. Then, the blower fan 40 stops due to the stop of the fan motor 40a accompanying the opening of the relay switch Y1, and at the same time, the motor 110a of the cam timer 110 also stops. As a result, the circulation of the air flow in the air flow circulation passage in the storage case 20 is stopped. The relay switch Ry is maintained in the excited state by closing the relay switch Y2 regardless of the state of the thermo switch Th2.
Maintains its compressive effect.

When the hot gas valve 100 is opened under the operation of the compressor 50 as described above, the high-temperature and high-pressure compressed refrigerant from the compressor 50 passes through the pipe P5, the hot gas valve 100, the pipe P6, and the downstream portion of the pipe P4 to the evaporator. Inflow to 30. Then, this inflowing compressed refrigerant heats the evaporator 30 and also becomes a low-temperature refrigerant, and returns to the compressor 50 through the pipe P1. After that, the evaporator 30 is heated by the inflowing compressed refrigerant under the repeated operation as described above while the blower fan 40 is stopped, and the temperature of the evaporator 30 rises. In such a case, even if the ambient temperature of the refrigerator main body B is low, since the blower fan 40 is stopped, the effect of the thermal energy of the compressed refrigerant due to the opening of the hot gas valve 100 does not decrease. Further, in the temperature rising process as described above, since the blower fan 40 is stopped, the frost that has grown on the surface of the evaporator 30 is mainly melted into water droplets and dripped into the dew tray, and the heater H1 is used. It is discharged to the outside of the freezer main body B without being frozen due to the heat generation effect of. In addition, in such a temperature rising process, the temperature inside the storage case 20 also gradually rises. When the internal temperature T reaches the upper limit set temperature Tu in this state, the thermo switch
Th2 closes.

Then, when the temperature of the evaporator 30 further rises and reaches the defrosting end temperature Tb as the defrosting progresses, the thermoswitch Th1 is opened and the relay coil Ry is demagnetized to close the relay switch Y1. Open relay switch Y2 together with. Then, the blower fan 40 exerts an air blowing action according to the operation of the fan motor 40a when the relay switch Y1 is closed, and the motor 110a of the cam timer 110 causes the switching contact 113
In the second throwing state, the operation is started and the predetermined defrosting time of the storage box is started. At this time, as described above, since the thermoswitch Th2 is closed even if the relay switch Y2 is opened, the relay coil Rx remains excited. Therefore, the compressor 50 continues its compression action.

As described above, the hot gas valve 100 is opened and the compressor 5
When the blower fan 40 operates under the operation of 0, the blower fan 40 circulates the heated airflow from the evaporator 30 through the airflow circulation passage as described above while heating the evaporator 30 with the compressed refrigerant. At this time, the evaporator 30
Since the temperature Tb is higher than the internal temperature T, the temperature of the circulating air flow by the blower fan 40 tends to decrease due to heat exchange with the storage box 20 of the circulating air flow. However, the temperature of the evaporator 30, due to the compressed refrigerant from the compressor 50,
Since the temperature continues to rise, the circulating air flow, which is about to decrease in temperature as described above, is heated again by the evaporator 30. In this way, the airflow from the blower fan 40 circulates in the airflow circulation passage while gradually increasing the temperature thereof. For this reason, the wall surface temperature of the storage case 20 gradually rises, and the frost that has grown on the inner wall surface of the storage case 20 melts into water droplets and drips, passing through the discharge pipe (not shown) and outside the refrigerator body B. Is discharged to.

Then, when the counting of the defrosting time of the storage box by the cam timer 110 is completed at t = t3 (see FIG. 6), the switching contact 113 is closed to the fixed contact 111. For this reason, the hot gas valve 110
The air-cooling fan 70 is restarted at the same time as is closed. This means that the refrigeration cycle R ends the defrost cycle and shifts to the same cooling cycle as described above. In this cooling cycle, since the temperature T in the refrigerator at the start is only slightly higher than the upper limit set temperature Tu, the time required for cooling the food to be refrigerated to the appropriate refrigeration temperature can be shortened.

As described above, even if frost grows in layers on the surface of the evaporator 30 and the inner wall of the storage box 20 in the course of the cooling cycle of the refrigeration cycle R, the defrosting cycle associated with the end of the cooling cycle of the refrigeration cycle R At the time of transition, under the stop of the blowing action of the blower fan 40, the high-temperature and high-pressure compressed refrigerant from the compressor 50 is caused to directly flow into the evaporator 30 by the hot gas valve 100 to heat the evaporator 30, so that the evaporator 30 is heated. The grown frost is mainly defrosted. Then, when the thermoswitch Th1 is opened due to the completion of defrosting of the evaporator 30, during the process of measuring the defrosting time of the storage box of the cam timer 110, the compressed refrigerant from the compressor 50 to the evaporator 30 while the hot gas valve 100 is opened. The storage box 20 is defrosted under the effect of heating the evaporator 30 and the blowing action of the blower fan 40 due to the inflow to the storage box 20.

In such a case, the defrosting of the evaporator 30 is performed by the thermal energy of the compressed refrigerant flowing into the evaporator 30 from the compressor 50 via the hot gas valve 100 while the blower fan 40 is stopped. Also, the defrosting of the evaporator 30 can be smoothly performed regardless of the reduction in the effect of the thermal energy of the compressed refrigerant. Further, the defrosting of the evaporator 30 is performed by using the thermal energy of the compressed refrigerant directly flowing into the evaporator 30 from the compressor 50 while the blower fan 40 is stopped, while the defrosting of the storage box 20 is performed by the evaporator 30. Since both the heat energy of the compressed refrigerant to the evaporator 30 after defrosting and the blowing action of the blower fan 40 to the air heated by this heat energy are used, both the evaporator 30 and the storage box 20 are made. Defrosting will be performed while always sufficiently securing the thermal energy required to melt each frost, and as a result, both defrosting of the evaporator 30 and the storage box 20 can be efficiently and accurately performed in a short time. . Since each defrosting process as described above is performed, the heating temperature of the evaporator 30 and the temperature of the circulating air flow may decrease due to the heat storage energy of the objects to be refrigerated in the storage box 20. Absent.

FIG. 7 shows a second embodiment of the present invention. In the second embodiment, the heater H0 is adopted instead of the hot gas valve 100 described in the first embodiment. It has the above characteristics. The heater H0 is arranged in the vicinity of the evaporator 30 so as to directly heat the evaporator 30 described in the first embodiment by its heat generating action, and the heater H0 has a common lead wire at one end thereof. It is connected to L1 and is connected to the fixed contact 112 of the cam timer 110 at the other end. Unlike the first embodiment, the compressor motor 50a is connected in parallel with the fan motor 70a.
Further, the relay switch Y2 described in the first embodiment is omitted. The other structure is similar to that of the first embodiment.

In the second embodiment having such a configuration, when the cooling cycle of the refrigeration cycle R is completed, the cam time 110 is changed from the first input state to the second input state as in the first embodiment.
Switch to the closed state. Therefore, at the same time that the compressor 50 and the air-cooling fan 70 stop, the heater H0 exerts its heat generating action and the evaporator 40 stops when the blower fan 40 stops.
Start defrosting 30. Then, when the defrosting of the evaporator 30 is completed by opening the thermoswitch Th1 as in the first embodiment, the blowing action of the blower fan 40 and the heater H0 are turned on during the process of measuring the defrosting time of the storage of the cam timer 110. The storage box 20 is defrosted under the effect of heat generation. As a result, even when the flow of the compressed refrigerant from the compressor 50 to the evaporator 30 via the hot gas valve 100 is replaced and the heating action of the heater H0 on the evaporator 30 is adopted,
The same defrosting effect as that of the embodiment can be obtained. Other functions and effects are similar to those of the first embodiment.

In addition, in the said 1st and 2nd Example, the example which made the defrosting end temperature Tb of the evaporator 30 which thermostat Th1 becomes an open state lower than the defrosting end temperature of the storage 20 is demonstrated. However, instead of this, the above-mentioned defrosting end temperature Tb is higher than the defrosting end temperature of the storage box 20,
For example, the thermoswitch Th1 may be configured so as to be Teu (see the point m on the curve Lb in FIG. 8). In such a case, in the same cooling cycle as described above, the temperature of the evaporator 30 changes as shown by the curve Lb along the curve L that specifies the internal temperature T, and then in the same defrosting cycle as described above, The temperature of 30 rapidly increases toward the temperature Teu specified by the point m. Therefore, since the defrosting heat storage energy of the evaporator 30 until the defrosting of the evaporator 30 is completed is larger than that of the first and second embodiments, the fan 40 blows air when defrosting the storage box 20. The temperature of the circulating air flow is rapidly increased as compared with the case of the first and second embodiments. As a result, even if it is difficult to defrost the stored heat due to the large amount of objects to be refrigerated in the storage box 20, the curve of FIG.
As indicated by La, the inner wall temperature of the storage box 20 that changes along the curve L changes from point n1 to point n2 (indicating the storage box defrosting end temperature) during the defrosting process of the storage box 20. As shown in the figure, the temperature rapidly rises, so that the storage box 20 can be defrosted properly in a short time.

Next, a third embodiment of the present invention will be described with reference to FIGS. 9 to 11. In the third embodiment, the normally closed relay switch Z1 is the fan described in the first embodiment. It is connected between the motor 70a and the fixed contact 111 of the cam timer 110. Further, unlike the first embodiment, the motor 110a of the cam timer 110 is connected between both common conductors L1 and L2. The normally open type relay switch Z2 is connected to the common conductor L2 at one end thereof, and the other end of the relay switch Z2 is connected to the common conductor L1 via the relay coil Ry and the thermoswitch Th1 described in the first embodiment. It is connected.

The relay coil Rz constitutes a relay together with both relay switches Z1, Z2 and a normally open type relay switch Z3.This relay switch Rz has a normally open type relay switch Y3 and a relay switch Z3 connected in parallel at one end thereof. Is connected to the common conductor L1 via the other end, and the thermoswitch Th3
Is connected to the common conductor L2 via. Then, the relay coil Rz is selectively excited by receiving an AC voltage from between the common conductors L1 and L2 through one of the relay switches Y3 and Z3 and the thermoswitch Th3. The relay switch Z1 is opened by exciting the relay coil Rz. Both relay switches
Z2 and Z3 are closed by exciting the relay coil Rz.

As shown in Fig. 10, the thermo switch Th3 has a storage box 20
The thermoswitch Th3 is attached to the center of the upper wall 22 from the inner surface side, and closes when the temperature of the inner surface of the center of the upper wall 22 falls to a predetermined lower limit inner surface temperature. Further, the thermoswitch Th3 is opened when the temperature of the central inner surface of the upper wall 22 rises to a predetermined upper limit inner surface temperature. The relay switch Y3 is closed by exciting the relay coil Ry in the first embodiment. The other structure is similar to that of the first embodiment.

In the third embodiment configured as described above, when the cooling cycle of the refrigeration cycle R is completed as shown in FIG. 11 as in the case of the first embodiment, the cam timer 110 is changed from the first closed state to the second Switched to the closed state, air-cooled fan 70
Is stopped by stopping the fan motor 70a, and the hot gas valve 110 is opened. This means that the refrigeration cycle R
Means a transition from the cooling cycle to the defrost cycle. At this time, the evaporator is used as in the first embodiment.
Since the temperature of 30 is low enough, the thermo switch
Th1 is closed. Therefore, when the cam timer 110 is turned on for the second time, the relay coil Ry is excited and the relay switch Y1
And both relay switches Y2 and Y3 are closed.

Then, the blower fan 40 stops due to the stop of the fan motor 40a accompanying the opening of the relay switch Y1, and the relay coil R
x is the thermoswitch T when the relay switch Y2 is closed.
Regardless of the operating state of h2, the excited state is maintained,
The compressor 50 is maintained in the operating state when the relay switch X is closed, and the relay coil Rz is connected to the relay switch Y3.
When the switch is closed, it is excited while the thermo switch Th3 is closed to open the relay switch Z1 and close both relay switches Z2 and Z3. Then, the relay switch Rz holds its excited state by closing the relay switch Z3 under the closing of the thermoswitch Th3, and the relay coil Ry is related to the operation of the thermoswitch Th1 by closing the relay switch Z2. Excited state without a hot gas valve
100, cam time 110 by closing the relay switch Z2
The fan motor 70a is maintained in the open state regardless of the operation of the cam timer 110, regardless of the operation of the cam timer 110, by opening the relay switch Z1. It should be noted that the cam timer 110 returns to the first charging state after measuring time for a short time after shifting to the defrosting cycle (see FIG. 11).

As described above, when the hot gas valve 100 is opened under the operation of the compressor 50, the defrosting of the evaporator 30 proceeds under the stop of the blower fan 40 as in the first embodiment.
In such a process, when the thermo switch Th2 is closed and the thermo switch Th1 is opened in the same manner as in the first embodiment, the relay coil Ry is demagnetized under the excitation of both relay coils Rx, Rz and blows air. The fan 40 exerts a blowing action under the operation of the compressor 50 and the opening of the hot gas valve 100. Therefore, as in the first embodiment, the evaporator is
The blower fan 40 circulates the heated airflow from the evaporator 30 along the peripheral wall of the storage case 20 through the airflow circulation passage while being heated by the compressed refrigerant of 30. This is a storage box 20
Means that defrosting has started.

When the inner surface temperature of the upper wall 22 of the storage case 20 rises to the predetermined upper limit inner surface temperature due to such defrosting, the thermoswitch Th3
Opens, the relay coil Rz is demagnetized, and the relay switch
Close Z1 and open both relay switches Z2 and Z3 (see Fig. 11). As a result, similarly to the first embodiment, the refrigeration cycle R ends the defrosting cycle and shifts to the cooling cycle. In such a case, the internal temperature of the upper wall 22 of the storage 20 is adjusted to 0 (° C) after adjusting the internal temperature T to 0 (° C) or more.
When the above adjustment is made, water droplets only adhere to the inner wall of the storage case 20 without freezing, and frost does not grow. Therefore, as described above, when the defrosting of the evaporator 30 is completed, the inner surface temperature of the storage case 20 has already risen to the defrosting completion temperature. Therefore, at the same time when the evaporator 30 is defrosted, the thermoswitch Th3 is opened, and the refrigeration cycle R shifts to the next cooling cycle without the unnecessary defrosting process of the storage box 20 as described above. As a result, the temperature in the storage box 20 does not unnecessarily rise, and the next cooling cycle can be realized while properly maintaining the refrigeration quality of the food to be refrigerated.

Further, when the inside temperature T is adjusted to be lower than 0 ° C., when frost is growing on the inner surface of the storage case 20, the defrosting end timing of the storage case 20 may change according to the amount of the frost. However, in such a case, the defrosting of the storage case 20 is performed on the assumption that the rising time of the inner surface temperature of the storage case 20 to the defrosting end temperature coincides with the defrosting end time of the storage case 20. The thermoswitch Th3 will always open at the end time.

Therefore, when the growth amount of frost in the storage box 20 is small, it is possible to realize a transition to the next cooling cycle of the refrigeration cycle R accompanying the end of defrosting of the storage box 20 at an early stage after the end of defrosting of the evaporator 30. As a result, the evaporator 30 does not deteriorate in the quality of refrigeration due to unnecessary temperature rise of the food to be refrigerated.
After completion of defrosting, the next cooling cycle is realized at an early stage. On the other hand, when the amount of frost growing in the storage box 20 is large,
After the defrosting of the evaporator 30 is completed, the refrigeration cycle R shifts to the next cooling cycle with a delay. This is
This means that the defrosting end time of the storage box 20 is delayed due to a large amount of frost.

As described above, in the third embodiment, as described in the first embodiment, the defrosting of the storage case 20 is not ended by the end of timing of the cam timer 110, but the end of defrosting by the thermoswitch Th3 is completed. Since the defrosting of the storage box 20 is ended by detecting the temperature, the defrosting time of the storage box 20 expands and contracts according to the amount of frost growth of the storage box 20, and the defrosting of the storage box 20 is always properly performed. After ensuring, the refrigerating cycle R is shifted to the next cooling cycle while maintaining the refrigerating quality of the food to be refrigerated. Other functions and effects are similar to those of the first embodiment.

FIG. 12 shows a fourth embodiment of the present invention.
The embodiment is characterized in that the heater H4 is adopted in place of the hot gas valve 100 in the third embodiment. The heater H4 is disposed in the vicinity of the evaporator 30 so as to directly heat the evaporator 30 in the third embodiment by its heat generation effect, and the heater H4 is connected to the common conductor L1 at one end thereof. The other end is connected to the fixed contact 112 of the cam timer 110 and the relay switch Z2. The compressor motor 50a
Are connected in parallel to the fan motor 70a. Also,
The relay switch Y2 in the third embodiment is omitted. The other structure is the same as that of the third embodiment.

In the fourth embodiment thus constructed, when the cooling cycle of the refrigerating cycle R is completed, as described in the third embodiment, the cam timer 110 is changed from the first closed state to the second
Switch to the closed state. Therefore, at the same time that the compressor 50 and the air-cooling fan 70 are stopped, the heater H4 exerts its heat generating action and the evaporator is stopped when the blower fan 40 is stopped.
Start defrosting 30. After that, when the defrosting of the evaporator 30 is completed by opening the thermoswitch Th1 as in the third embodiment, the defrosting of the storage case 20 is performed due to the blowing action of the blower fan 40 and the heating action of the heater H4. Be started. As a result, when the heating action of the heater H4 on the evaporator 30 is adopted instead of the flow of the compressed refrigerant from the compressor 50 to the evaporator 30 via the hot gas valve 100,
While changing the defrosting time of the storage box 20 in the same manner as the third embodiment according to the adjustment of the temperature inside the storage box 20 and the inner surface temperature of the upper wall 22 and the growth amount of frost in the storage box 22, the evaporator 30 After the defrosting is completed, the same operation and effect as those of the third embodiment can be achieved in the process of shifting the refrigeration cycle R to the next cooling cycle.

[Brief description of drawings]

1 to 5 are overall block diagrams showing the first embodiment of the present invention, FIG. 6 is a time chart for explaining the operation of the main constituent elements in the first embodiment, and FIG. 7 is the present invention. FIG. 8 is a time chart for explaining the operation of a variation of each of the above embodiments, and FIGS. 9 and 10 show a third embodiment of the present invention. Configuration of essential parts, 11th
FIG. 12 is a time chart for explaining the operation of main constituent elements in the third embodiment, and FIG. 12 is a fourth chart of the present invention.
It is a principal part circuit diagram which shows an Example. Explanation of code 10 …… Insulation box, 20 …… Storage box, 30 …… Evaporator, 40
...... Blower fan, 40a …… Fan motor, 50 …… Compressor, 50a …… Compressor motor, 100 …… Hot gas valve, 110 …… Cam timer, B …… Refrigerator body, H0, H4…
… Heater, Th1, Th2, Th3 …… Thermo switch, Rx, Ry, Rz
…… Relay coil, X, Y1 to Y3, Z1 to Z3 …… Relay switch.

Claims (5)

[Claims] 1. A refrigerator body in which a storage box is disposed in a heat insulation box, and an air flow circulation passage is formed between an inner wall of the heat insulation box and an outer wall of the storage box, and an inflow refrigerant in an operating state. Means for compressing the compressed refrigerant into a high-temperature high-pressure compressed refrigerant, a refrigerant state conversion means for condensing the compressed refrigerant into a low-temperature low-pressure refrigerant, and a cooling function arranged in the air flow circulation passage according to the inflow of the low-temperature low-pressure refrigerant And a refrigerating cycle comprising evaporation means for causing the inflowing refrigerant to flow into the compression means, and valve means for directly flowing the compressed refrigerant from the compression means into the evaporation means to heat the evaporation means when opening, Fan means disposed in the air flow circulation passage for circulating the air flow from the evaporation means through the air flow circulation passage according to the operation, and the temperature inside the storage box is the lower limit of a predetermined cooling temperature range. Value (or When the temperature of the evaporating means rises to a predetermined evaporating means defrosting ending temperature, the first temperature detecting means is set to the first (or second) detection state when the upper limit value) is reached, and this is detected. Controlled so as to drive the compression means in the second detection state of the second temperature detection means for detecting and the first temperature detection means and stop the compression means in the first detection state of the first temperature detection means. The first control means and the evaporation means are in the first closed state for a predetermined cooling time to close the valve means, and when the cooling time has elapsed the second closed state is in the open state for the valve means. When a predetermined storage defrosting time has elapsed after the detection by the second temperature detecting means, the first
When the timer switch means in the closed state and the second temperature detecting means are not detected, the fan means is stopped when the timer switch means is in the second closed state, and is detected by the second temperature detecting means. A refrigerator comprising second control means for controlling the fan means to operate. 2. A refrigerator body in which a storage box is disposed in a heat insulation box, and an air flow circulation passage is formed between an inner wall of the heat insulation box and an outer wall of the storage box, and in the air flow circulation passage. A refrigerating cycle that has an evaporating means disposed in the air flow circulating passage, the refrigerating cycle causing the evaporating means to perform a cooling function according to a circulating refrigerant, and the air flow from the evaporating means depending on the operation. Fan means for circulating through the air flow circulation passage,
A heating means which is arranged in the vicinity of the evaporating means and heats the evaporating means by a heat generating action, and a heating means for heating the evaporating means when the temperature in the storage box reaches a lower limit value (or an upper limit value) of a predetermined cooling temperature range. A first temperature detecting means that detects and becomes a first (or a second) detection state; and a second temperature detecting means that detects when the temperature of the evaporating means rises to a predetermined evaporating means defrosting end temperature. A first control means for controlling the refrigeration cycle to operate in the second detection state of the first temperature detection means and to stop the refrigeration cycle in the first detection state of the first temperature detection means; During the predetermined cooling time by the evaporating means, the first charging state is maintained and the heating means is maintained under the non-heat generating action, and when the cooling time elapses, the second charging state is maintained and the heating means is maintained under the heat generating action. 2 Predetermined after detection by temperature detection means It said during the course of the repository defrosting time first
When the timer switch means in the closed state and the second temperature detecting means are not detected, the fan means is stopped when the timer switch means is in the second closed state, and is detected by the second temperature detecting means. A refrigerator provided with a second control means for controlling the fan means to operate. 3. The refrigerator according to claim 1, wherein the defrosting end temperature of the evaporation means is set higher than the defrosting end temperature of the storage box. . 4. A refrigerator main body comprising a storage box disposed inside a heat insulation box, and an air flow circulation passage formed between an inner wall of the heat insulation box and an outer wall of the storage box; Means for compressing the compressed refrigerant into a high-temperature high-pressure compressed refrigerant, a refrigerant state conversion means for condensing the compressed refrigerant into a low-temperature low-pressure refrigerant, and a cooling function arranged in the air flow circulation passage according to the inflow of the low-temperature low-pressure refrigerant And a refrigerating cycle comprising evaporation means for causing the inflowing refrigerant to flow into the compression means, and valve means for directly flowing the compressed refrigerant from the compression means into the evaporation means to heat the evaporation means when opening, Fan means disposed in the air flow circulation passage for circulating the air flow from the evaporation means through the air flow circulation passage according to the operation, and a temperature in the center of the storage box within a predetermined cooling temperature range. lower limit( Is the upper limit value), which is detected when it reaches the first (or second) detection state, and when the temperature of the evaporation means rises to a predetermined evaporation means defrosting end temperature. Second temperature detecting means for detecting this,
When the temperature of the inner surface of the peripheral wall of the storage box is lower (or higher) than the predetermined inner surface temperature, the third temperature detecting means which detects the temperature and enters the first (or second) detection state, and the first temperature detecting means In the second detection state, the compression means is driven to control the first temperature detection means to stop the compression means in the first detection state, and during the predetermined cooling time by the evaporation means, A timer switch means that is in a first closed state and closes the valve means, and is in a second closed state when the cooling time elapses and opens the valve means; and the timer switch when the second temperature detecting means is not detected. Means for stopping the fan means when the means is in the second closed state, and controlling the fan means to operate under the detection of the second temperature detecting means; and a third temperature detecting means. 1 (or second) detection Refrigerator and a third control means for controlling so as to maintain the control state of an open state and the second control means of the valve means in state (or release). 5. A refrigerator main body, wherein a storage box is arranged in a heat insulation box, and an air flow circulation passage is formed between an inner wall of the heat insulation box and an outer wall of the storage box, and the air flow circulation passage. A refrigerating cycle that has an evaporating means disposed therein and causes the evaporating means to perform a cooling function in accordance with a circulating refrigerant; and an air flow from the evaporating means that is disposed in the air flow circulation passage depending on the operation. Fan means for circulating the air in the air circulation passage, heating means arranged near the evaporation means for heating the evaporation means by heat generation, and temperature in the storage box within a predetermined cooling temperature range. When the lower limit value (or the upper limit value) is reached, the temperature of the first temperature detecting means that detects the lower limit value (or the upper limit value) and becomes the first (or second) detection state and the temperature of the evaporating means are equal to a predetermined evaporating means defrosting end temperature Second temperature detecting means for detecting this when the temperature rises to A second temperature detecting means that the temperature of the inner surface of the peripheral wall of the paying box is detected condition of lower than a predetermined inner surface temperature (or high) when first detects this (or second), the first
First control means for operating the refrigeration cycle in the second detection state of the temperature detection means and controlling the refrigeration cycle to stop in the first detection state of the first temperature detection means;
A timer switch means that keeps the heating means in a non-heat generating state during a predetermined cooling time by the evaporating means and keeps the heating means in a second closing state after the cooling time elapses and keeps the heating means under heat generating action. And the fan means is stopped when the timer switch means is in the second closing state without the detection of the second temperature detection means, and the fan means is operated under the detection of the second temperature detection means. Second control means for controlling the first temperature of the third temperature detecting means
In the (or second) detection state, the heat generating action of the heating means and the control state of the second control means are maintained (or released).
A refrigerator comprising a third control means for controlling so as to perform.