JP2007071520A - Cooling storage box, and control method for its compressor - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To carry out operation with higher efficiency by preventing responding with unnecessary sensitiveness with respect to sudden change of an internal temperature. <P>SOLUTION: A deviation calculating means 42 calculates a deviation between the internal temperature detected by a temperature sensor 35, and a target temperature provided from a target temperature setting means 41 at every predetermined time. The deviations are integrated by a deviation integrating means 46, and under a condition that the integrated value exceeds a predetermined reference value, a rotational frequency of an inverter motor driving the compressor is increased. By this, for example, even if a door is temporarily opened, outside air flows into a storage chamber interior, and the internal temperature temporarily rises, there is no sudden change in the integrated value of the temperature deviations. Thus, the rotational frequency of the compressor will not suddenly become fast due to sensitive response, and control is stabilized. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a cooling storage for driving a compressor by an inverter motor and a method for controlling the compressor.

  In recent years, for example, in commercial refrigerators, those equipped with an inverter compressor capable of speed control are becoming widespread (for example, see Patent Document 1).

Although there are various advantages provided with the inverter compressor, an example is an increase in efficiency during the control cooling operation. This is because when the control cooling operation is performed to maintain the inside of the chamber at the set target temperature, when the chamber temperature approaches the target temperature, the speed (rotation speed) of the inverter compressor is decreased step by step accordingly. To control. When this control method is adopted, the continuous on-time of the compressor is overwhelmingly long. In other words, the number of on / off switching operations is greatly reduced, and high efficiency and energy saving are achieved.
JP 2002-195719 A

  However, the conventional control method obtains the deviation between the internal temperature and the target temperature at regular intervals, and when the deviation is large, the rotational speed is increased, and when the deviation is small, the rotational speed is decreased. There was a problem that the rotational speed fluctuation of the inverter compressor became unnecessarily large. For example, if the door is repeatedly opened and closed temporarily during controlled cooling operation where the interior is maintained near the target temperature suitable for cooling the food, the interior temperature will suddenly rise rapidly. There appears a time when the deviation from the temperature temporarily increases. In such a case, even if the internal temperature suddenly rises, the food contained in the internal storage has a large heat capacity, so the temperature has not increased so much, but according to the conventional control method, the inverter compressor Is determined depending on the magnitude of the deviation between the internal temperature and the target temperature, so that the rotational speed is immediately increased.

  However, even in this case, if the door is closed and a certain amount of time has passed, the internal temperature drops rapidly, and although the rotational speed can be kept low again, it responds unnecessarily to a temporary rise in temperature. As a result, the rotational speed is increased, which is not preferable from the viewpoint of efficiency.

  The present invention has been completed based on the above situation, and can prevent a response with an unnecessary sensitivity to a sudden change in the internal temperature, and can be operated with higher efficiency. It aims at providing the control method of a storage and its compressor.

  As means for achieving the above object, the invention of claim 1 compresses a refrigerant by a compressor driven by an inverter motor, and supplies the refrigerant to a cooler through a condenser and a throttle device. A method for controlling the compressor in a cooling storage that cools the storage chamber with the generated cold air, the target temperature setting means for setting the target temperature in the storage chamber, and the internal temperature in the storage chamber is detected A temperature sensor, and calculates and integrates a deviation between the target temperature set in the target temperature setting means and the internal temperature detected by the temperature sensor every predetermined time, and the integrated value and a predetermined reference The present invention is characterized in that the rotational speed of the inverter motor is changed based on the comparison with the value.

  The cooling storage according to the invention of claim 2 is a compressor driven by an inverter motor, a condenser that radiates heat from a refrigerant compressed by the compressor, and a cooler that is supplied with refrigerant from the condenser through a throttling device. And a heat-insulated storage in which the storage chamber is cooled by the cool air generated by the cooler, target temperature setting means for setting a target temperature in the storage chamber of the heat-insulating storage, and the temperature in the storage chamber is detected Calculated by the temperature sensor, a deviation calculating means for calculating a deviation between the target temperature set in the target temperature setting means every predetermined time and the internal temperature detected by the temperature sensor, and calculated by the deviation calculating means. Deviation integration means for integrating the sum of the predetermined number of deviations, and the integrated value integrated by the deviation integration means is compared with a reference value to change the rotation speed of the inverter motor. Characterized in place and a rotational speed control means for.

  The cooling storage according to the invention of claim 3 is a compressor driven by an inverter motor, a condenser for radiating heat from a refrigerant compressed by the compressor, and first and second flow paths for the refrigerant from the condenser. A valve device that selectively switches to the first and second flow paths, first and second coolers that are individually provided in the first and second flow paths and that are selectively supplied with the refrigerant, and the first and second A throttling device provided between the refrigerant inlet side to the second cooler and the condenser, and first and second storage chambers, and these storage chambers are formed by the cold air generated by the respective coolers. A heat-insulated storage to be cooled; target temperature setting means for setting a target temperature in the first and second storage chambers; and a temperature sensor for detecting the internal temperature in each of the first and second storage chambers. The eye set in the target temperature setting means every predetermined time Deviation calculating means for calculating the deviation between the temperature and the internal temperature detected by the temperature sensor, deviation integrating means for integrating the sum of the predetermined number of deviations calculated by the deviation calculating means, and this deviation integrating means The present invention is characterized in that it comprises rotation speed control means for changing the rotation speed of the inverter motor by comparing the integrated integrated value with a reference value.

  The invention of claim 4 is characterized in that, in the invention of either claim 2 or claim 3, the target temperature setting means is configured to sequentially output different target temperatures as time passes.

  According to a fifth aspect of the present invention, the target temperature setting means stores, in the storage means, a function representing a temporal change mode of the target temperature, and reads out the function stored in the storage means so that the target temperature is set as time passes. It has a feature in a configuration including target temperature calculation means for calculating temperature.

  The invention according to claim 6 is characterized in that the target temperature setting means is stored as a reference table in which the temporal change mode of the target temperature is compared with the temperature and the elapsed time, and in the storage means as time passes. It is characterized in that it is configured to include table reading means for reading the target temperature.

  According to the control method of the present invention, the deviation between the target temperature set in the target temperature setting means and the internal temperature detected by the temperature sensor is calculated and integrated every predetermined time, and the integrated value and the predetermined reference Since the rotation speed of the inverter motor that drives the compressor is changed based on the comparison with the value, for example, the door is temporarily opened, and the inside temperature temporarily rises due to the outside air flowing into the storage chamber. However, since there is no sudden change in the integrated value of the temperature deviation, the speed of the compressor does not react rapidly and the speed does not increase rapidly, so that the control is stable, which contributes to power saving.

<Embodiment 1>
A first embodiment of the present invention will be described with reference to FIGS.

  In this embodiment, the case where it applies to the vertical refrigerator for business is illustrated, First, FIG. 1 demonstrates the whole structure. This refrigerator is composed of a vertically insulated heat storage 10 with a front opening, and is supported by legs 11 standing at the four corners of the lower surface, and the inside is a refrigeration room 12 which is a storage room. A front opening of the refrigerator compartment 12 is partitioned into two upper and lower openings 14 by a partition frame 13, and a heat insulating door 15 is attached to each opening 14 so as to be swingable in a horizontal direction.

  On the upper surface of the heat insulating storage 10, a machine room 18 is provided surrounded by a panel 17, and a refrigeration unit 20 installed on a base 19 is accommodated therein. As shown in FIG. 2, the refrigeration unit 20 includes a compressor 22 driven by an inverter motor 21 to compress refrigerant, a condenser 24 cooled by a condenser fan 23, a dryer 25, and a capillary tube 26 corresponding to an expansion device. A cooler 27 for evaporating the refrigerant that has passed through the capillary tube 26 and an accumulator 28 are connected by circulation through a refrigerant pipe 29, and the base 19 closes the window hole 16 formed in the ceiling wall of the refrigerator compartment 12. It is attached in this way.

  A drain pan 30 that also serves as an air duct is stretched on the lower surface side of the window hole 16 in the ceiling portion of the refrigerator compartment 12, and a cooler chamber 31 is formed above the drain pan 30. The bottom surface of the drain pan 30 is formed to have a downward slope toward the rear edge (left side in FIG. 1), and a blowout port 33 is cut out on the rear edge side. In addition, a suction port 32 is opened in a region on the front side of the drain pan 30, and the air in the refrigerator compartment 12 is sucked by a fan 34 provided on the upper side of the drain pan 30 and cooled by a cooler 27 to be blown out. 33 is returned to the refrigerator compartment 12. In the cooler chamber 31, a temperature sensor 35 for detecting the internal temperature in the refrigerator compartment 12 is provided at a position where the internal air flowing in from the suction port 32 comes into contact.

  The inverter motor 21 is driven by an inverter drive circuit 36 that outputs AC power having a variable frequency, and the output frequency is determined by the controller 40. The controller 40 will be described in detail with reference to FIG. 2. This is a target temperature setting means 41 for setting a target temperature in the refrigerator compartment 12, a target temperature Ta set by the target temperature setting means 41, and the target temperature Ta. Deviation calculating means 42 for calculating a deviation (T-Ta) from the internal temperature T detected by the temperature sensor 35 is provided.

  The target temperature setting means 41 has the configuration shown in FIG. 3 in the present embodiment, and the target temperature Ta is given as its temporal change mode (that is, the state in which the target temperature Ta is changed with time t). The target temperature change mode includes a target temperature change mode at the time of control operation in which stored items such as foods are cooled to a set temperature set by the user, for example, when the power is turned on for the first time after installing a refrigerator. As described above, there are two types of target temperature change modes during so-called pull-down cooling operation in which cooling is performed from a temperature considerably higher than the set temperature during control operation to a temperature range during control operation. In this embodiment, each change mode is represented by a function f (t) with the time t as a variable, and the function is stored in the storage means 43 constituted by, for example, EPROM. For example, as the function f (t) for calculating the change mode of the target temperature Ta during the pull-down cooling operation, the function represented by the graph shown in FIG. 4 can be exemplified.

On the other hand, the target temperature setting means 41 is provided with a well-known time measuring means 44 constituted by, for example, a pulse oscillation circuit and a counter (not shown), from which a time measuring signal corresponding to the passage of time is output. The time measurement signal is given to the target temperature calculation means 45, where the target temperature Ta is calculated every predetermined time. More specifically, first, the internal temperature T0 is read from the temperature sensor 35 when the controller 40 is started (when the power is turned on), and the initial time value t0 is calculated from the equation t0 = f ⁻¹ (T0) based on the value. (See FIG. 5). Thus, when the elapsed time from the start is t, the target temperature Ta can be expressed by a function including a constant number Ta = f (t + t0) (see FIG. 6). Therefore, the target temperature calculation means 45 reads the above function from the storage means 43 at predetermined time intervals of 5 seconds, for example, based on the time measurement signal (indicating the value of t) from the time measurement means 44, and sets the initial time values t0 and t. Is substituted for the target temperature Ta.

  As described above, the target temperature Ta from the target temperature calculating means 45 is given to the deviation calculating means 42 together with the internal temperature T obtained from the temperature sensor 35, and here the deviation (T-Ta) is calculated. Then, the value of the deviation is given to the deviation integrating means 46 in the next stage. Here, for example, the deviation for 2 minutes to 10 minutes (in this embodiment, 5 minutes, that is, 5 * 60/5 = 60 times) is sequentially applied. The accumulated value A is given to the rotational speed control means 47. The rotation speed control means 47 compares the deviation accumulated value A with a predetermined reference value (lower limit value and upper limit value), and when the accumulated value A is larger than the upper limit value L_UP, the inverter motor 31 increases the rotation speed of the inverter motor 31. When the frequency command signal Sf to the drive circuit 36 is changed and the integrated value ΣA is smaller than the lower limit value L_DOWN, the frequency command signal Sf to the inverter drive circuit 36 is changed so as to decrease the rotation speed of the inverter motor 31. It has become. The function of the rotational speed control means 47 is realized by software executed by the CPU, and the processing procedure of the software is as shown in FIG.

  The software configuration will be described with reference to FIG. When the compressor rotation control start routine is started by the CPU (step S1), the integrated value A is first initialized to, for example, 0 (step S2). Next, as described above, the target temperature setting means 41 calculates the target temperature Ta (step S3), and the deviation A from the internal temperature T is calculated and integrated (the deviation calculating means 42 and the deviation integrating means 46). Function: Step S4). In step S5, the integrated value is compared with the upper limit value L_UP and the lower limit value L_DOWN, and the rotational speed of the inverter motor 31 is increased or decreased (function of the rotational speed control means 47: steps S5 to S7).

  According to this embodiment, for example, assuming that the temporal change mode of the target temperature during the pull-down cooling operation is set as shown in the graph shown by the one-dot chain line in FIG. 8, the actual internal temperature is as shown by the solid line. If it has changed, since the internal temperature is cooled lower than the target temperature at the beginning of the cooling operation, the temperature deviation becomes negative and the integrated value A also becomes negative. Here, the graph of the integrated value A has a sawtooth waveform because the integrated value A is initialized every time the rotational speed of the inverter motor 31 is changed (step S8 in FIG. 7). When the integrated value A becomes negative and falls below the lower limit value L_DOWN, the inverter frequency is gradually decreased (see time zone t1). As a result, the compressor rotational speed is decreased stepwise to suppress the cooling capacity. For this reason, the internal temperature approaches the degree of decrease in the target temperature.

  As a result of the reduced cooling capacity, if the internal temperature exceeds the target temperature (time zone t2), the temperature deviation and its integrated value A change to positive, and the compressor is located when the integrated value A exceeds the upper limit value L_UP. The number of revolutions is increased, the cooling capacity is increased, and the internal temperature again approaches the degree of decrease in the target temperature. Hereinafter, by repeating such control, the internal temperature decreases in accordance with the temporal change mode of the set target temperature.

  And even if the heat insulation door 15 of the heat insulation storage 10 is temporarily opened in the middle of the pull-down cooling operation as described above and the inside temperature temporarily rises due to the flow of outside air, the temperature rise is Since the heat insulating door 15 is quickly restored by being closed, there is no sudden change in the integrated value as long as the integrated value of the temperature deviation is observed. For this reason, the controller 40 does not react sensitively and does not rapidly increase the rotation speed of the compressor 22, so that the control is stabilized, thereby contributing to power saving.

  In the above description, the pull-down cooling operation is described. However, the upper and lower limits are set above and below the set temperature even in the control operation for cooling the stored product such as food to the set temperature set by the user. The change mode of the target temperature indicating how to change the internal temperature from the upper limit value to the lower limit value in terms of time is functionalized and stored in the storage means 43, as in the pull-down cooling operation. Thus, the rotation speed of the compressor is controlled. Therefore, even during the control operation, it does not react sensitively to a temporary sudden change in the internal temperature due to the opening and closing of the heat insulating door 15, and power saving can be achieved. In addition, since the compressor 22 is controlled so as to follow the stored target temperature change mode, the operation stop time of the compressor 22 can be appropriately ensured. A defrosting function can be demonstrated and it can prevent frost formation in large quantities.

  In commercial refrigerators, the above-mentioned pull-down cooling operation is not limited to the initial installation of the refrigerator, but is a rerun after a few hours have passed since turning off the power, and a long time when carrying a large amount of food. This is necessary even when the door is opened for a long time or when a large amount of high-temperature food is put in immediately after cooking, and its cooling characteristics are extremely important. In view of that point, in the present embodiment, the cooling characteristics during the pull-down cooling operation are not simply given as the final target value of the temperature, but are given as a change with time of the target temperature. A common refrigeration unit 20 can be used for the insulated storage.

  In particular, in this embodiment, since the change mode of the target temperature is converted into a function and stored in the storage unit 43, there is an advantage that the storage capacity can be smaller than that stored in a table.

<Embodiment 2>
Next, a second embodiment of the present invention will be described with reference to FIGS.

  In this embodiment, the case where it is applied to a commercial refrigerator (table type) in a refrigerator is illustrated. First, the overall structure will be described with reference to FIG. Reference numeral 50 denotes a heat insulating storage, which is configured by a horizontally long heat insulating box that opens to the front surface, and is supported by legs 51 provided at the four corners of the bottom surface. The inside of the heat insulating storage 50 is partitioned into left and right by a heat insulating partition wall 52 to be attached later, the left relatively narrow side is a freezer compartment 53F corresponding to the first storage room, the right wide side is the second It is a refrigerating room 53R corresponding to a storage room. Although not shown, a swing-type heat insulating door is attached to the opening in front of the freezer compartment 53F and the refrigerator compartment 53R so as to be opened and closed.

  A machine room 58 is provided on the left side of the heat insulating storage 50 as viewed from the front. A heat-insulating cooler chamber 60 communicated with the freezer compartment 53F is formed on the back side of the upper part in the machine room 58, and a freezing unit 70 described later is accommodated in the lower part thereof so that it can be taken in and out. Yes. Further, another cooler chamber 64 is formed on the surface of the partition wall 52 on the refrigerator compartment 53R side by stretching a duct 63.

  As shown in FIG. 10, the refrigeration unit 70 includes a compressor 72 that is driven by an inverter motor 71 to compress a refrigerant, and a refrigerant discharge side of the compressor 72 is cooled by a condenser fan 73 and a condenser 74. The dryer 75 is connected to the inlet side of a three-way valve 76 that is a valve device. One outlet of the three-way valve 76 is connected to a first cooler 78F accommodated in the cooler chamber 60 on the freezing chamber 53F side via a capillary tube 77F corresponding to a throttling device. The other outlet of the three-way valve 76 is connected to the second cooler 78R accommodated in the cooler chamber 64 on the refrigerating chamber 53R side via a capillary tube 77R that is also a throttling device. The refrigerant outlet of the first cooler 78F is connected with the accumulator 79F and the check valve 80 in order, and the refrigerant outlet of the second cooler 78R is joined with the accumulator 79R, and finally the compressor 72 is joined. It is connected to the inhalation side. Thereby, when the three-way valve 76 is switched, the refrigerant from the condenser 74 returns to the compressor 72 via the capillary tube 77F, the first cooler 78F, the accumulator 79F, and the check valve 80 in this order. 82F, and a capillary tube 77R, a second cooler 78R, and an accumulator 79R are selectively switched to a second flow path 82R that returns to the compressor 72 in order, and the refrigerant is switched to the first and second coolers 78F. , 78R can be selectively supplied.

  The three-way valve 76 is switched so as to alternately activate the first and second flow paths 82F and 82R every predetermined time during the period in which the compressor 72 is driven. . Each of the cooler chambers 60 and 64 is provided with temperature sensors 83F and 83R for detecting the internal temperatures of the freezing chamber 53F and the refrigerating chamber 53R at positions where the internal air is in contact.

  As in the first embodiment, the inverter motor 71 is driven by an inverter drive circuit 86 that outputs AC power of variable frequency, and the output frequency is determined by the controller 90. The controller 40 will be described in detail with reference to FIG. 10. This is a target temperature setting means 91 for setting target temperatures in the freezer compartment 53F and the refrigerator compartment 53R, and a target set by the target temperature setting means 91. Deviation calculating means 92 is provided for calculating a deviation of the temperature from the actual internal temperature detected by the two temperature sensors 83F and 83R. Here, when the target temperature of the freezer compartment 53F is TFa, the actual internal temperature is TF, the target temperature of the refrigerator compartment 53R is TRa, and the actual internal temperature is TR, the above deviation is (TF-TFa) and ( TR-TRA)).

  The target temperature setting means 91 is the same as that of the first embodiment shown in FIG. 3 in the second embodiment, except that the two target temperatures TFa and TRa for the freezer compartment 53F and the refrigerator compartment 53R are output. is there. That is, each target temperature of the freezer compartment 53F and the refrigerator compartment 53R is given as a change mode with time (that is, a state in which the target temperature is changed with the time t). Of the target temperature during control operation to cool the stored items to the set temperature set by the user, and for example, when the power is turned on for the first time after installing the refrigerator-freezer, There are two types of change modes of the target temperature in the so-called pull-down cooling operation in which cooling is performed from a considerably high temperature to the temperature range during the control operation, and each change mode is expressed by a function with the time t as a variable, The function is stored in a storage means constituted by, for example, EPROM. For example, the functions TFa = fF (t) and TRa = fR (t) indicating the change modes of the target temperatures TFa and TRa of the freezer 53F and the freezer 53R during the pull-down cooling operation are represented by the graph shown in FIG. The thing can be illustrated.

  The two target temperatures TFa and TRa from the target temperature setting means 91 are given to the deviation calculating means 2 together with the two internal temperatures TF and TR obtained from the temperature sensors 83F and 83R. Here, the respective deviations (TF− TFa) and (TR-TRA) are calculated. Then, the value of each deviation is given to the deviation integrating means 96 at the next stage, and here, for example, the deviation for 2 minutes to 10 minutes (5 minutes in this embodiment) is calculated on the refrigerator compartment 53R side and the freezer compartment 53F side. Both are added together and integrated, and the value is given to the rotational speed control means 97. The rotation speed control means 97 compares the integrated value of the deviation with a predetermined reference value (lower limit value and upper limit value), and increases the rotation speed of the inverter motor 71 when any of the integrated values is larger than the upper limit value L_UP. When the frequency command signal Sf to the inverter drive circuit 86 is changed so that one of the integrated values is smaller than the lower limit value L_DOWN, the frequency command signal Sf to the inverter drive circuit 86 is decreased to decrease the rotation speed of the inverter motor 71. Is to change. The function of the rotation speed control means 47 is realized by software executed by the CPU, and the processing procedure of the software is as shown in FIG.

  The software configuration will be described with reference to FIG. When the compressor rotation control start routine is started by the CPU (step S1), the integrated value A is first initialized to, for example, 0 (step S2). Next, as described above, the target temperature setting means 91 calculates the respective target temperatures TRa and TFa of the refrigerator compartment 53R and the freezer compartment 53F (steps S3 and S4), and the target temperatures TRa and TFa and the actual interior temperature Deviation A between temperatures TR and TF is calculated and integrated (functions of deviation calculating means 92 and deviation integrating means 96: step S5). In step S6, the integrated value is compared with the upper limit value L_UP and the lower limit value L_DOWN, and the rotational speed of the inverter motor 71 is increased or decreased (function of the rotational speed control means 97: steps S6 to S8).

  According to the second embodiment as described above, for example, the temporal change modes of the respective target temperatures TFa and TRa of the refrigerator compartment 53R and the freezer compartment 53F during the pull-down cooling operation are set as shown by a dashed line in FIG. Assuming that the actual storage temperatures TF and TR of the refrigerator compartment 53R and the freezer compartment 53F change as indicated by the solid line, for example, at the beginning of the cooling operation on the refrigerator compartment 53R side, the internal temperature compared to the target temperature TRa. Cooling is performed so that TR is lower, and on the freezer compartment 53F side, cooling is performed so that the internal temperature TF is substantially equal to the target temperature TFa. Therefore, the overall temperature deviation is negative, and the integrated value A is also negative. become. Here, the reason why the graph of the integrated value A has a sawtooth waveform is that the integrated value A is initialized every predetermined time (step S9 in FIG. 12). Since the integrated value A becomes negative and falls below the lower limit value L_DOWN, the inverter frequency is gradually lowered at the beginning. As a result, the compressor speed is lowered step by step, and the cooling capacity is suppressed. The temperature approaches the degree of decrease in the target temperature.

  If the internal temperature exceeds the target temperature as a result of the decrease in cooling capacity, the temperature deviations of the freezing room 53F and the refrigerating room 53R and their integrated values A change to positive, and the integrated integrated value A becomes the upper limit value L_UP. When the pressure exceeds the value, the compressor rotational speed is increased to increase the cooling capacity, and the internal temperature again approaches the degree of decrease in the target temperature. Hereinafter, by repeating such control, the internal temperature decreases in accordance with the temporal change mode of the set target temperature.

  And even if the heat insulation door 15 of the refrigerator heat insulation storage 10 is temporarily opened during the pull-down cooling operation as described above and the inside temperature temporarily rises due to the flow of outside air, the temperature rises. Is rapidly restored by closing the heat insulating door, so as long as it is observed as an integrated value of temperature deviation, there is no sudden change in the integrated value. For this reason, the controller 90 does not react sensitively and does not rapidly increase the rotation speed of the compressor 72, so that the control is stabilized, which contributes to power saving.

  In the above description, the pull-down cooling operation is described. However, the upper and lower limits are set above and below the set temperature even in the control operation for cooling the stored product such as food to the set temperature set by the user. The change mode of the target temperature indicating how to change the internal temperature from the upper limit value to the lower limit value in terms of time is functionalized and stored in the storage means, in the same manner as in the pull-down cooling operation. The rotational speed of the compressor is controlled. Therefore, even during the control operation, it does not react sensitively to a temporary sudden change in the internal temperature due to the opening and closing of the heat insulating door, and power saving can be achieved. Further, since the compressor 72 is controlled so as to follow the stored target temperature change mode, the operation stop time of the compressor 72 can be appropriately ensured, and each of the coolers 78F and 78R. It is possible to prevent a large amount of frost from being exhibited by exhibiting a kind of defrosting function.

  In commercial refrigerators, the above-mentioned pull-down cooling operation is not limited to the initial installation of the refrigerator, but is a rerun after a few hours have passed since turning off the power, and a long time when carrying a large amount of food. This is necessary even when the door is opened for a long time or when a large amount of high-temperature food is put in immediately after cooking, and its cooling characteristics are extremely important. In view of that point, in the present embodiment, the cooling characteristics during the pull-down cooling operation are not simply given as the final target value of the temperature, but are given as a change with time of the target temperature. A common refrigeration unit 70 can be used for the insulated storage.

  In addition, in the present embodiment, since the target temperature is given as the target temperature for every predetermined time when the target temperature is given as the change mode with time, for example, compared with the case where the target temperature is given as the rate of change in temperature every predetermined time, 1 There is an advantage in that the refrigerant from the compressor 72 of the stand is supplied to the two coolers 78F and 78R alternately to be adapted to a cooling storage type of cooling the two chambers. That is, if the cooling target is given as the rate of change in temperature every predetermined time and the rotation speed of the compressor 72 is controlled so as to approach the rate of change, one of the types in which cooling is performed alternately is cooled. While the door of the other storage room is temporarily opened and the internal temperature rises, for example, the internal temperature decreases as soon as the door is closed and the storage room is cooled. The target rate of change for the cooling operation is achieved. For this reason, although the internal temperature actually rises slightly, the rotational speed of the compressor 72 is reduced, and when such a situation is returned, the internal temperature is expected. Can not be lowered.

  On the other hand, in this embodiment, since the temporal change mode of the target temperature is given as a target temperature that is different (slowly decreases) every predetermined time, there is a temporary rise in the internal temperature. In this case, if the target temperature cannot be reached at that time, the number of revolutions of the compressor 72 is increased and the cooling capacity is increased, so that the internal temperature can be reliably lowered as set.

<Other embodiments>
The present invention is not limited to the embodiments described with reference to the above description and drawings. For example, the following embodiments are also included in the technical scope of the present invention, and further, within the scope not departing from the gist of the invention other than the following. Various modifications can be made.

  (1) In each of the above embodiments, the deviation between the target temperature and the internal temperature is calculated and integrated every predetermined time, and when the integrated value exceeds a predetermined reference value, the rotational speed of the compressor is immediately set. However, other conditions may be taken into account when determining the rotational speed of the compressor.

  (2) In each of the above embodiments, as shown in FIG. 3, the target temperature setting means stores a function representing a temporal change mode of the target temperature in the storage means 43, and the function stored in the storage means 43 is stored in the function. The target temperature is calculated in accordance with the passage of time by reading out. However, the present invention is not limited to this. For example, as shown in FIG. 14, a reference table in which the temporal change mode of the target temperature is compared with the elapsed time. Is created in advance, this reference table is stored in the storage means 100, and the target temperature in the storage means 100 is read by the table reading means 101 according to the signal from the timing means 102 as time passes. It is good also as a structure.

1 is an overall cross-sectional view showing Embodiment 1 of the present invention. Refrigeration cycle configuration diagram of Embodiment 1 The block diagram which shows the structure of the target temperature setting means of Embodiment 1. The graph which shows the time-dependent change aspect of the target temperature in Embodiment 1. The graph which shows the calculation process of the initial value in Embodiment 1. The graph which shows the time-dependent change aspect of the target temperature determined in Embodiment 1. The flowchart which shows the control procedure of the compressor rotation speed in Embodiment 1. FIG. The graph which shows the relationship between the change aspect of the chamber temperature at the time of the pull-down cooling operation in Embodiment 1, and a compressor rotation speed Whole sectional drawing which shows Embodiment 2 of this invention Refrigeration cycle configuration diagram of Embodiment 2 The graph which shows the time-dependent change aspect of the target temperature of the freezer compartment and refrigerator compartment in Embodiment 2. Flowchart showing the control procedure of the compressor rotation speed in the second embodiment. The graph which shows the relationship between the change mode of the internal temperature at the time of the pull-down cooling operation in Embodiment 2, and a compressor rotation speed The block diagram which shows other embodiment which varied the target temperature setting means

Explanation of symbols

  DESCRIPTION OF SYMBOLS 10 ... Thermal insulation storage 12 ... Refrigeration room 22 ... Compressor 26 ... Capillary tube (throttle device) 27 ... Cooler 35 ... Temperature sensor 41 ... Target temperature setting means 42 ... Deviation calculation means 46 ... Deviation integration means 47 ... Speed control means DESCRIPTION OF SYMBOLS 50 ... Thermal insulation storage 51 ... Target temperature calculation means 53F ... Freezing room (1st storage room) 53R ... Refrigeration room (2nd storage room) 72 ... Compressor 76 ... Three-way valve (valve apparatus) 77F, 77R ... Capillary tube (Throttle device) 78F ... first cooler 78R ... second cooler 82F ... first flow path 82R ... second flow path 91 ... target temperature setting means 92 ... deviation calculating means 96 ... deviation integrating means 97 ... Speed control means

Claims (6)

Control of the compressor in the cooling storage that compresses the refrigerant by the compressor driven by the inverter motor, supplies the refrigerant to the cooler through the condenser and the expansion device, and cools the storage chamber by the cold air generated by the cooler. A method,
A target temperature setting means for setting a target temperature in the storage chamber; and a temperature sensor for detecting an internal temperature in the storage chamber;
The deviation between the target temperature set in the target temperature setting means and the internal temperature detected by the temperature sensor is calculated and integrated every predetermined time, and based on a comparison between the integrated value and a predetermined reference value A method for controlling a compressor in a cooling storage, wherein the rotational speed of the inverter motor is changed. A compressor driven by an inverter motor, a condenser that dissipates heat from the refrigerant compressed by the compressor, a cooler to which the refrigerant from the condenser is supplied through a throttling device, and cold air generated by the cooler An insulated storage room in which the storage room is cooled, target temperature setting means for setting a target temperature in the storage room of the insulated storage room, a temperature sensor for detecting the internal temperature of the storage room, and the target at predetermined time intervals Deviation calculating means for calculating a deviation between the target temperature set in the temperature setting means and the internal temperature detected by the temperature sensor, and a deviation for integrating the sum of the predetermined number of deviations calculated by the deviation calculating means An integrating means; and a rotational speed control means for comparing the integrated value integrated by the deviation integrating means with a reference value to change the rotational speed of the inverter motor. Retirement reservoir. A compressor driven by an inverter motor; a condenser for radiating heat from the refrigerant compressed by the compressor; a valve device for selectively switching the refrigerant from the condenser to the first and second flow paths; First and second coolers that are individually provided in the first and second flow paths and to which the refrigerant is selectively supplied, the refrigerant inlet side to the first and second coolers, and the A throttle device provided between the condenser, first and second storage chambers, and the storage chambers cooled by the cold air generated by each of the coolers; Target temperature setting means for setting a target temperature in the second storage chamber, a temperature sensor for detecting the internal temperature in each of the first and second storage chambers, and the target temperature setting means at predetermined time intervals Detected by the set target temperature and the temperature sensor Deviation calculating means for calculating the deviation from the internal temperature, deviation integrating means for integrating the sum of the predetermined number of deviations calculated by the deviation calculating means, and the integrated value integrated by the deviation integrating means as a reference value A cooling storage comprising a rotation speed control means for changing the rotation speed of the inverter motor in comparison. 4. The cooling storage according to claim 2, wherein the target temperature setting means is configured to sequentially output different target temperatures as time passes. The target temperature setting means is a storage means for storing a function representing a temporal change mode of the target temperature, and a target temperature calculation for reading the function stored in the storage means and calculating the target temperature as time passes. 5. A cold storage according to claim 2, comprising means. The target temperature setting means stores storage means as a reference table in which the temporal change mode of the target temperature is contrasted between temperature and elapsed time, and table reading means for reading out the target temperature in the storage means as time elapses The cooling storage of Claim 2 thru | or 4 provided with these.

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