JP2000121225A - Refrigerating installation - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a refrigerating installation which can rationally carry out power saving operation. SOLUTION: A refrigerating installation 100 cools an object 70 to be cooled by an evaporating section 20 of a refrigerant 20a and an air blower 21A. Decrease of an operation factor Tr of a compressing section 10 for compressing the refrigerant 20a is stepwise determined [constitution of power saving operation], whereby the compressing section 10 is shifted to each decreased step. At a first decreased step, rotational speed Rs11 of an electric motor 11B of the compressing section 10 is decreased, whereby the compression amount is repeatedly decreased by a predetermined amount at the compressing section 10 for a plurality of number of times. At a second decreased step, rotational speed Rs21 of the air blower 21A is repeatedly decreased, whereby the circulation amount of cold air in the installation is decreased for a plurality of number of times. At a third decreased step, both the rotational speed Rs11 of the electric motor 11B and the rotational speed Rs21 of the air blower 21A are decreased. The same decreased steps as the first to third decreased steps are repeatedly carried out for a plurality of number of times. If the operation factor Tr exceeds a predetermined value at each decreased operation step, the operation returns to the immediately preceding step. On the other hand, if new cooling load is generated, the operation returns to a normal operation. The decrease of the rotational speed is carried out by an inverter circuit, etc.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an apparatus for refrigeration or freezing or refrigeration and freezing of articles by a cooling function by refrigerant compression (hereinafter referred to as a compression cooling function) (hereinafter referred to as a refrigeration apparatus). .

[0002]

2. Description of the Related Art Refrigerators having such a compression cooling function include, for example, refrigerated or frozen food showcases, commercial refrigerators or freezers or freezers / refrigerators, and cold drink vending machines.

In a refrigeration system, the rotational speed of an electric motor that drives a compression mechanism of a heat-operated fluid, that is, a compression mechanism for compressing a heat-operable fluid, that is, a liquefiable refrigerant, for example, Freon gas, is varied. That is,
The configuration of the refrigerating apparatus 100 of FIG. 3 in which the number of revolutions per unit time is changed (hereinafter, referred to as a first related art) is disclosed in Japanese Patent Publication No. 61-27990. In addition, in the following figures, the part shown with a thick line is the flow path of a refrigerant, ie, a pipe. In the following drawings, portions indicated by the same reference numerals are portions having the same function.

In FIG. 3, a cooling object 70 to be cooled by the compression cooling function is a refrigerator 71,
1 is configured to be cooled by the heat exchanger 21 of the evaporating section 20. Therefore, the cooling load is
The temperature varies depending on the temperature and amount of the articles (not shown) stored in the storage unit 1.

[0005] The compression section 10 compresses a gaseous refrigerant to obtain a compressed refrigerant 10a. The compressed refrigerant 10a is condensed by heat exchange with the outside air in the heat exchanger 41 of the condensing unit 40, and the condensed refrigerant 4a is condensed.
0a, the pressure is reduced by the pressure reducing unit 30 and the reduced pressure refrigerant 3
0a, and the reduced-pressure refrigerant 30a is supplied to the heat exchanger 2 of the evaporator 20.
After being vaporized by heat exchange with the cooling medium inside the refrigerator 71 to become the gaseous refrigerant 20a in 1, the compression unit 10
It is configured to repeat the refrigerant circulation of returning to.

The compression unit 10 includes a compression mechanism 11A, for example,
The rotary type compressor, the reciprocating type compressor, etc.
B, for example, by driving a synchronous motor, an induction motor, or the like, compresses the gaseous refrigerant 20a to compress the compressed refrigerant 10a.
a, and the heat exchanger 41 of the condenser 40
For example, the condensed refrigerant 40a is obtained by circulating the compressed refrigerant 10a and radiating the heat through a pipe that passes through the radiating fin group in a meandering manner. It should be noted that there is also a configuration in which a blower (not shown) is provided as necessary and external air is sent to the radiating fin group of the heat exchanger 41 to promote heat radiation.

[0007] The compression amount adjusting unit 50 includes, for example, the electric motor 11.
A variable frequency circuit 51 for changing the frequency of the power supply given to B, for example, an inverter circuit, which changes the rotation speed of the electric motor 11B by changing the frequency of the power supply and thereby compresses the refrigerant in the compressor mechanism 11A. Is changed.

The decompression section 30 is, for example, a capillary tube 31 having a large flow resistance in a flow path through which the condensed refrigerant 40a passes.
a is obtained. In addition, the capillary tube 31
Instead, an expansion valve or the like can be used.

The evaporating section 20 cools articles to be refrigerated by exchanging heat with a cooling medium in the refrigerator 71, for example, air through a reduced pressure refrigerant 30a through a heat exchanger 21 formed by a meandering pipe. The fan 21A circulates a cooling medium in the refrigerator 71, for example, air to promote cooling of the articles to be refrigerated.

The control section 60 is a section for performing control processing mainly by a control processor (hereinafter, referred to as a CPU) by a microcomputer, for example. Refrigerator 7 based on the detection signal of temperature detector S1 provided in
1 controls the compression section 10 so that the temperature in the first section 1 becomes a target temperature. Specifically, based on a detection signal of the temperature detector S1, a rotation speed RS11 of the electric motor 11B,
It controls the amount of air blown by the blower 21A, that is, the rotation speed RS21 of the drive motor (not shown) of the blower 21A (hereinafter, referred to as the rotation speed of the blower 21A), and the operation and suspension of these.

In the first prior art, the object to be cooled 70 is replaced by a refrigerator 71 instead of the refrigerator 71, and each control is controlled to match the freezing temperature of the articles in the freezer (hereinafter referred to as the second prior art). Is also well known.

Further, as shown in FIG. 4, a refrigerator 71A / refrigerator 71B is used in place of the refrigerator 71 in the configuration of the first prior art as described above, and the same control is performed (hereinafter referred to as a "first refrigerator"). 3 Prior Art)
No. 261624.

In FIG. 4, the heat exchanger 21 of the evaporator 20
Is provided between partition walls 72 and 73 provided between the freezer 71A and the refrigerator 71B, and a cooling medium, for example, air in the refrigerator is supplied to the partition walls 72 and 73 and the freezer 71A / freezer 71B by the blower 21A. The freezer 71A and the freezer 71B are configured to circulate through respective passages between the inner wall 75 and the freezer 71A and the freezer 71B.

The cooling is performed mainly on the freezer 71A side, and in order to cool the refrigerator 71B side with the excess cool air, a flow adjusting section 80, for example, a damper 81 driven by an electric motor is provided in a passage toward the refrigerator 71B side. Is provided, and the adjustment of the opening angle of the damper 81 is controlled by the control unit 60.

Further, as shown in FIG. 5, a compression amount adjusting unit 50 for adjusting the compression amount of the compression unit 10 is configured to vary the compression amount by controlling the rotation speed of the electric motor 11B, for example, a commercial AC power supply. A DC power supply is rectified by rectifying a predetermined AC power supply, and an inverter circuit or the like is operated with the DC power supply to obtain an AC power supply having a required frequency, and a variable frequency circuit 51 for varying the frequency is provided. (Hereinafter, referred to as a fourth prior art) is disclosed in Japanese Patent Application Laid-Open No. 5-99484.

Further, the motor 11B is constituted by a synchronous motor 11B1, as shown in FIG.
Inverter circuit 51A or cycloconverter circuit 5
A configuration for controlling the rotation speed of the synchronous motor 11B1 through the intermediary of the electric motor 1B is disclosed in, for example, "Electrical Engineering Handbook", Chapter 17, Chapter 9, "Non-rectifier Motor" issued by the Institute of Electrical Engineers of Japan in April 1978.

The control of the rotation speed of the electric motor 11B in the [non-commutator motor configuration] in FIG. 5 is basically configured as [rotation speed control / basic configuration] in FIG. Are configured as [DC type / inverter type configuration] and [AC type / cyclo converter type configuration] in FIG.

In FIG. 5 (rotation speed control / basic configuration), a variable frequency circuit 51 is a variable frequency converter 51X whose frequency can be controlled by a control circuit 51B. The control circuit 51B controls the variable frequency converter 51X based on the detection signal of the rotor position of the synchronous motor 11B1 detected by the rotor position detector PS while generating the voltage of the required frequency and applying it to the synchronous motor 11B1. It is configured as follows.

The [DC / inverter type configuration] (hereinafter referred to as a fifth prior art) in FIG.
Basic configuration], the AC power supply 1 is a three-phase AC power supply 1a, the variable frequency circuit 51 is composed of a rectifier circuit 2 and an inverter circuit 51A, and the motor 11B is a three-phase synchronous motor 11A.
B2, the output voltage of the rectifier circuit 2 is controlled by the control circuit 51B2, and the frequency of the inverter circuit 51A is controlled by the control circuit 51B1.

More specifically, in the [DC type / inverter type configuration] of FIG. 5, the rectifier circuit 2 controls the conduction time width of the plurality of thyristors SY1 by the control circuit 51B2 to supply the DC current to the inverter circuit 51A. Controlling voltage. The DC reactor DL is for blocking a pulsating component after rectification. In addition, if necessary, a smoothing capacitor is provided.

The inverter circuit 51A includes a rectifier circuit 2
Is applied to each field coil FL of the three-phase synchronous motor 11B2 via the plurality of thyristors SY2, and the control circuit 51B1 performs the control based on the detection signal of the position of the rotor RT detected by the rotor position detector PS. The rotation speed of the rotor RT is controlled by controlling the conduction time width of the plurality of thyristors SY2.

The [AC type / cycloconverter type configuration] of FIG. 5 (hereinafter referred to as a sixth prior art) is different from the [rotation speed control / basic configuration] of FIG. 5 in that the AC power supply 1 is a three-phase AC power supply 1a. The variable frequency circuit 51 is composed of a cycloconverter circuit 51C, and the motor 11B is a three-phase synchronous motor 1
1B2 and the cycloconverter circuit 51C
Is controlled by the control circuit 51B3.

More specifically, in the [AC type / cyclo converter type configuration] shown in FIG.
Is applied to each field coil FL of the three-phase synchronous motor 11B2 via each DC reactor DL and a plurality of thyristors SY3 of the cycloconverter circuit 51C,
The control circuit 51B3 controls the conduction time width of the plurality of thyristors SY3 based on the detection signal of the position of the rotor RT detected by the rotor position detector PS, whereby the rotor RT
This controls the rotation speed. That is, the plurality of thyristors SY3 are configured to serve as both a rectifier circuit and a frequency conversion circuit.

It should be noted that the three-phase AC power supply 1a in the [DC / inverter type configuration] of FIG. 5 of the fifth prior art and the [AC / cyclo converter type configuration] of FIG. The three-phase synchronous motor is changed to a single-phase AC power supply and a single-phase synchronous motor, and the inverter circuit 51A
Alternatively, a configuration in which the cycloconverter circuit 51C has a single-phase configuration corresponding to a single-phase AC power supply and a single-phase synchronous motor (hereinafter, referred to as a seventh conventional technique) is also known.

The electric motors 11B, 11B1, 11B in the case where the configurations of the fourth to seventh prior arts are applied to the configurations of the first to third prior arts.
Control circuits 51B, 51B1, 51B2,
Control of 51B3, that is, control of the variable frequency circuit 51, is performed by the control unit 60. As a configuration of such a control unit 60, a configuration as shown in FIG. 6 (hereinafter, referred to as an eighth conventional technique) is well known.

In FIG. 6, for example, the control unit 60
Commercially available control processing board CPU /
B, and detection data of each detection signal obtained by each detector, for example, each detector S1, etc., and the setting operation unit 6
The necessary input data obtained by inputting the data 6 is taken from the input / output port 61 and stored in the working memory 63.

The input data stored in the working memory 63
Processing is performed on the detected data, reference data for control processing stored in advance in the data memory 64, such as reference value data for the detection value of each detection unit S1, time data obtained from the clock circuit 65, and the like. Each of the obtained control data is processed based on a control processing flow program stored in advance in the working memory
3 is stored.

Each control signal based on each control data stored in the work memory 63 is supplied from the input / output port 61 to each control unit, for example, the control unit such as the blower 41A, the variable frequency circuit 51, and the electronic expansion valve 32. Further, the data which the operator needs to monitor among the data stored in the working memory 63 and the like is provided from the input / output port 61 to the display unit 67 and displayed.

The operation of the cooling operation in the first prior art to the third prior art, ie, the operation of suspending or suspending the operation of the compression unit 10, that is, the operation of suspending the operation, as shown in FIG. The period Tx and the suspension period Ty are performed alternately. The blower 21A is operated simultaneously with the compression unit 10.
The operation is stopped or the operation / stop is appropriately repeated while the compression unit 10 is operating. The total period Tz of the compression unit 10 and one suspension period following the one operation period Tx is called an operation cycle Tz, and the ratio of the operation period Tx to the operation cycle Tz is called an operation ratio Tr. That is, Tr
= Tx / Tz.

This operation / pause operation is performed in the data memory 6.
4 based on the reference value data stored in advance or the reference value data input by operating the setting operation unit 66.
When the temperature in the refrigerator 71, that is, the data of the temperature value detected by the temperature detector S1 becomes higher than the predetermined temperature value t2 on the high temperature side, the cooling operation is started, and the data of the temperature value is changed to the low temperature side. When the temperature becomes equal to or lower than the predetermined temperature value t1, the cooling operation is stopped.

Now, as shown in FIG. 7, if the refrigerator 71 is turned on when the temperature of the refrigerator 71 is at the temperature value T3, and the operation is started, the temperature inside the refrigerator 71 decreases due to the cooling operation. Then, when the temperature reaches the low-temperature-side predetermined temperature value t1, the cooling operation is stopped.

Then, during the suspension of the cooling operation, the refrigerator 71
Leakage due to the heat insulation properties of the outer shell of the refrigerator or refrigerator 7
The temperature in the refrigerator 71 rises due to the leakage of cold heat due to the opening and closing of the door 1 and the cooling operation is started when the temperature reaches the high temperature side predetermined temperature value t2. Thereafter, similarly, the temperature rising period from the low-temperature predetermined temperature value t1 to the high-temperature predetermined temperature value t2 is referred to as a pause period Ty, and the temperature falling period from the high-temperature predetermined temperature value t2 to the low-temperature predetermined temperature value t1 is similarly defined. Operation period T
The operation cycle x is continued.

Therefore, when the door of the refrigerator 71 is kept closed, there is little leakage of cold heat, so that the value of the operation rate Tr gradually decreases as in the first cycle → second cycle → third cycle. I will do it.

Further, for example, when the door of the refrigerator 71 is opened and closed after the third cycle, or when an article requiring cooling is newly introduced into the refrigerator 71, the temperature in the refrigerator 71 suddenly rises. As a result, the operation rate suddenly increases as in the fourth cycle. In addition, the period of the operation cycle Tr is changed to the above-described operation cycle Tr, and the suspension period Ty
May be a period from the start point of the operation period to the end point of the operation period Tx.

[0035]

SUMMARY OF THE INVENTION
In the configuration of the third related art, even when the value of the operation rate Tr gradually decreases as in the first cycle → second cycle → third cycle in FIG. The driving power, that is, the power supplied to the electric motor 11B, and the driving power for circulating the cool air in the refrigerator 71, that is, the power supplied to the blower 21A are considerably large, and the operation from the viewpoint of power saving is not performed.

It would be extremely convenient if a reasonable refrigeration system capable of performing such a cooling operation by a power-saving operation would be extremely convenient. There is a problem of whether it is good.

[0037]

SUMMARY OF THE INVENTION The present invention performs a cooling operation for cooling a cooling target with a compressed refrigerant obtained by compressing the above-described refrigerant in a compression section, and circulates cool air in the storage of the cooling target. In the refrigeration apparatus configured as described above,

When the operation rate of the cooling operation becomes equal to or less than a predetermined value, a control for reducing one or both of the amount of the compressed refrigerant and the amount of the circulated cool air in the compression section is performed. A first configuration provided with control means for performing

In the above-mentioned first configuration, when the operation rate becomes equal to or less than a first predetermined value, the amount of compression of the refrigerant is reduced, and the operation rate becomes higher than the first predetermined value. A second configuration for reducing the amount of circulation of the cool air when the temperature is below a small second predetermined value,

In the above-mentioned first configuration, when the operation rate becomes equal to or less than a first predetermined value, the amount of compression of the refrigerant is reduced, and the operation rate becomes higher than the first predetermined value. When the operating rate becomes equal to or less than a second predetermined value, the cooling air circulation amount is reduced. When the operating rate becomes equal to or less than a third predetermined value smaller than the second predetermined value, A third configuration for reducing the amount of compression of the refrigerant and reducing the amount of circulation of the cool air,

In the first configuration, when the operation rate becomes equal to or less than a first predetermined value, the amount of compression of the refrigerant is reduced, and the operation rate becomes higher than the first predetermined value. When the operating rate becomes equal to or less than a second predetermined value, the cooling air circulation amount is reduced. When the operating rate becomes equal to or less than a third predetermined value smaller than the second predetermined value, A fourth configuration in which stepwise reduction of reducing the amount of compression of the refrigerant and reducing the amount of circulation of the cold air is provided in a plurality of stages;

In the first configuration, the second configuration, the third configuration, or the fourth configuration,
The amount of compression of the refrigerant is reduced by reducing the rotation speed of the electric motor that drives the compression unit, and the amount of circulation of the cool air is reduced by reducing the rotation speed of the blower that circulates the cool air. Has solved the above-mentioned problem.

[0043]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS As an embodiment of the present invention, an embodiment in which the present invention is applied to the configuration of the first prior art will be described.

[0044]

An embodiment will be described below with reference to FIGS.
In FIGS. 1 and 2, portions denoted by the same reference numerals as those in FIGS. 3 to 7 are portions having the same functions as the portions denoted by the same reference numerals described with reference to FIGS. 3 to 7. 1 and 2 are portions having the same functions as the portions denoted by the same reference numerals described in any of FIG. 1 and FIG.

The configuration of this embodiment is different from the configuration of the first prior art shown in FIG. 3 in that, first, the operation stage of the cooling operation is first reduced to the first stage in FIG. 6, the cooling operation is reduced by providing a plurality of reduction stages in the method of reducing the cooling operation, and each operation stage is determined by the operation rate T.
This is a part configured to be determined by r.

Second, the reduction in the cooling operation in each reduction step is performed by reducing the amount of compression of the refrigerant 20a in the compression unit 10, for example, by reducing the rotation speed Rs11 of the electric motor 11B, This is a portion configured to be performed by reducing the circulation amount of cool air, for example, by reducing the rotation speed Rs21 of the blower 21A.

Third, a reduction step in which the manner of reduction is changed in the reduction step, for example, a reduction step in which only the compression amount of the refrigerant 20a in the compression section 10 is reduced as in the first reduction step, A reduction step in which only the amount of circulating cool air in the refrigerator 71 is reduced, as in the second reduction step;
As in the third reduction stage, this is a portion provided with a reduction stage in which both the reduction of the amount of compression of the refrigerant 20a in the compression section 10 and the reduction of the amount of circulation of cool air in the refrigerator 71 are provided.

Fourthly, the above-mentioned first reduction stage to
From the fourth reduction stage to the reduction stage by the third reduction stage,
Like the reduction stage by the sixth reduction stage, a similar reduction stage is provided in a plurality of stages.

That is, generally, firstly, a cooling operation for cooling the cooling target 70 with the compressed refrigerant 10a obtained by compressing the refrigerant 20a in the compression section 10 as described above is performed, and for example, Cooling target 70 by 21A
In the refrigerator 100 configured to circulate cool air in the refrigerator, for example, cool air in the refrigerator 71,

When the operation rate Tr of the cooling operation becomes a predetermined value or less, for example, a predetermined value X1 or less to a predetermined value X3 or less, the compression amount of the refrigerant 20a in the compression section 10 and the cold air For reducing one or both of the circulation amounts of the motor 11B, for example, the rotation speed Rs of the electric motor 11B.
This constitutes the above-described first configuration provided with control means for performing control for reducing one or both of the rotation speed Rs21 of the fan 11A and the blower 21A.

Second, in the above-described first configuration, the operation rate Tr is equal to or less than a first predetermined value, for example, a predetermined value X.
When it becomes 1 or less, the compression amount of the refrigerant 20a is reduced, for example, by reducing the rotation speed Rs11 of the electric motor 11B, and the operation rate Tr becomes higher than the first predetermined value, for example, the predetermined value X1. Is smaller than or equal to a second predetermined value, which is smaller than or equal to a predetermined value X2.
The amount of cool air circulated by the blower 21A
This constitutes the above-described second configuration that is reduced by reducing the rotation speed Rs21 of 1A.

Third, in the above-described first configuration, the operation rate Tr is equal to or less than a first predetermined value, for example, a predetermined value X.
When it becomes 1 or less, the compression amount of the refrigerant 20a is reduced, for example, by reducing the rotation speed Rs11 of the electric motor 11B, and the operation rate Tr becomes higher than the first predetermined value, for example, the predetermined value X1. Is smaller than or equal to a second predetermined value, which is smaller than or equal to a predetermined value X2.
The amount of cool air circulated by the blower 21A
Reduced by reducing the rotation speed Rs21 of 1A,

The operating rate Tr is equal to the second predetermined value,
For example, when the rotation speed becomes equal to or less than a third predetermined value smaller than the predetermined value X2, for example, the predetermined value X3 or less, for example, the above-described refrigerant 20 due to a decrease in the rotation speed Rs11 of the electric motor 11B is reduced.
This constitutes the third configuration in which the amount of compression of a is reduced and the amount of circulation of the cool air is reduced by, for example, reducing the rotation speed Rs21 of the blower 21A. .

Fourth, in the above-described first configuration, the operating rate Tr is equal to or less than a first predetermined value, for example, a predetermined value X.
When it becomes 1 or less, the compression amount of the refrigerant 20a is reduced, for example, by reducing the rotation speed Rs11 of the electric motor 11B, and the operation rate Tr becomes higher than the first predetermined value, for example, the predetermined value X1. Is smaller than or equal to a second predetermined value, which is smaller than or equal to a predetermined value X2.
The amount of cool air circulated by the blower 21A
Reduced by reducing the rotation speed Rs21 of 1A,

The operating rate Tr is equal to the second predetermined value,
For example, when the rotation speed becomes equal to or less than a third predetermined value smaller than the predetermined value X2, for example, the predetermined value X3 or less, for example, the above-described refrigerant 20 due to a decrease in the rotation speed Rs11 of the electric motor 11B is reduced.
The above-described fourth configuration is provided in which a plurality of stages of reduction of the amount of compression of a and reduction of the amount of circulation of the cool air by reducing the rotation speed Rs21 of the blower 21A are provided in a plurality of stages. That is what you will be.

Fifth, the first configuration described above and the second configuration described above
In the third configuration, the third configuration, or the fourth configuration, the compression amount of the refrigerant 20a is reduced by reducing the rotation speed Rs11 of the electric motor 11B that drives the compression unit 10; The fifth configuration described above is configured to reduce the amount of cool air circulation by reducing the rotation speed Rs21 of the blower 21A that circulates cool air.

Specifically, each data such as a predetermined value of each operation stage in [power saving operation configuration] in FIG.
Each data that can perform the best power saving operation, for example, the data such as [power saving operation configuration] in FIG. 1 is obtained in advance by a test operation of the apparatus, and stored in the data memory 64 of the control unit 60 in advance. In addition, the program according to the control processing flow of FIG.
2 so that the cooling operation according to the above-described first to fifth configurations can be performed.

Here, among the operation stages, the steady stage is based on the data of the value detected by the temperature detector S1, as described in the first to third prior arts, as shown in the operation configuration of FIG. The cooling operation, the rotation speed Rs1 of the electric motor 11B.
1 is a predetermined value A, for example, 3000 rpm;
The rotation speed Rs21 of 1A is set to a predetermined value B, for example, 2700
It is configured to be performed as rpm. In the present invention, the rotation speed Rs21 of the blower 21A refers to the rotation speed of the electric motor driving the blower 21A, as described in the related art.

The rotation speed Rs11 of the electric motor 11B is reduced by controlling the variable frequency circuit 51, for example, an inverter circuit by the control unit 60. In order to reduce the rotation speed Rs21 of the blower 21A, a variable frequency circuit (not shown) similar to the variable frequency circuit 51, for example, an inverter circuit is provided for a motor (not shown) for driving the blower 21A. The variable frequency circuit is controlled by the control unit 60.

The first to sixth reduction stages are determined by the operation rate Tr, and the time at which the determination is made is determined by a standby time after performing the reduction operation in each of the reduction stages, for example, a predetermined value Ta. To Tf, for example, at the time when three cycles of the operation cycle Tz have elapsed, so that the transient operation rate Tr immediately after the operation stage is changed
The determination is made at the time when the cooling operation after the change is substantially stabilized, instead of making the determination at the change portion of.

The calculation and storage of the data of the operation rate Tr are performed by the control of the control unit 60 under the control of the time period Tx in which the time of the operation of the motor 11B is measured by the clock circuit 65.
And the calculation of Tz = Tx + Ty, and Tr = Tx based on the data of the stop period Ty measured by the clock circuit 65 and the time of the stop period of the operation of the motor 11B.
/ Tz is calculated, and a program in which the obtained data of the operating rate Tr is stored in the working memory 63 is stored in the processing memory 62 in advance.

In the trowel control process, the value of the operation rate Tr used for discrimination takes into account a plurality of cycles of the operation cycle Tz, for example, three cycles, in consideration of fine fluctuations and transient fluctuations of the cooling operation. The average value of the operating rates Tz over a period of minutes is used.

As the operation rate Tr for discriminating each operation stage, a predetermined value which is determined to be appropriate obtained in advance by a test operation of the apparatus or the like is stored in the data memory 64 in advance. During the steady operation, the operation period Tx:
The suspension period Ty = 2: 1, and the operation rate Tr = 2/3 = 6
Since the value is 6.67%, the predetermined value X1 is changed to 9
The predetermined value X2 to X3 is set based on a low 60% corresponding to about 0%.

[Explanation of Control Processing Flow] The control processing flow of FIG. 2 will be described below. The control processing flow of FIG. 2 is configured as a subroutine of a main control processing routine for performing a steady control processing of the apparatus, and is performed at predetermined time intervals, for example, every two seconds. It is configured to shift. This transition may be made to the end point of each operation cycle in the main control processing flow.

In FIG. 2, at step SP1, the data of the operating rate Tr is fetched, and it is determined whether or not the operating rate Tr is equal to or less than a predetermined value X1, for example, 60% or less. If there is, the process proceeds to the next step SP2; otherwise, the process returns to a predetermined step of the main control processing routine.

Here, when it is determined that the difference is equal to or less than the predetermined value X1, there is no loading of a new cooling load because the door of the refrigerator 71 has not been opened or closed for a certain period of time. No new cooling load was loaded because no article requiring cooling was newly inserted, and it is determined that the cooling operation is in an operation stage where power saving can be performed.

In step SP2, the rotation speed Rs11 of the electric motor 11B is reduced by a predetermined value A1, for example, 60 rpm, to 2940 rpm, and
After the compression amount at 0 is reduced, the process proceeds to the next step SP3. That is, here, it has shifted from the steady operation stage to the power saving state of the first reduction stage.

In step SP3, after waiting for a waiting time Ta, for example, a time corresponding to three operation cycles Tz, the process proceeds to the next step SP4. Here, when the configuration of the refrigeration apparatus 100 does not cause a large change in the operation rate Tr transiently even when the compression amount is changed, the standby time Ta is set to a very short period, for example, 1 It may be about the number of cycles. Note that the standby times Tb to Tf described below are used.
The same applies to.

Further, the standby time Ta may be determined by a time value, and the clock circuit 65 may measure the time value, and then proceed to the next step. The same applies to the standby times Tb to Tf described later.

In step SP4, it is determined whether or not the operation rate Tr is equal to or less than a predetermined value X1, for example, 60% or less.
Otherwise, the process proceeds to the next step SP5. Here, the fact that it is not less than the predetermined value X1 means that the operation rate Tr
Is likely to have risen.

In step SP5, the rotational speed Rs11 of the electric motor 11B is increased by a predetermined value A1, for example, 60 rpm, and returned to 3000 rpm. Step S
Move to P6.

In step SP6, as in step SP3, after waiting for the elapse of the standby time Ta, step S6
Return to P1. If the predetermined value X1 is exceeded in step SP1, the operating rate Tr has increased because a new cooling load has been loaded, and the state is returned to the normal operation state by the main control processing routine.

In step SP7, it is determined whether or not the number of times the reduction of the rotation speed Rs11 of the electric motor 11B in step SP2 is repeated is a predetermined number of repetitions N1, for example, three times. Is performed, the process proceeds to the next step SP8, and if not, the process proceeds to step S8.
Return to P2. Therefore, when moving to step SP8, the predetermined value A1 for three times, for example, 60 rpm × 3 =
It is 2820 rpm, which has been reduced by 180 rpm.

Here, the number of repetitions N1 is determined, for example, by
Each time the control process of step SP2 is performed, "+1" is given to the corresponding flag F1 and discrimination is made based on the number-of-times data sequentially added.
9 and when the control processing of step SP5 is performed, the count data is reset to “0”. The same applies to the predetermined values N2 to N4 described later.

In step SP8, it is determined whether or not the operating rate Tr is equal to or less than a predetermined value X2, for example, 50% or less. If the operating rate Tr is equal to or less than the predetermined value X2, the process proceeds to the next step SP9. If not, the process returns to step SP5.

Here, when it is determined that it is equal to or less than the predetermined value X2, it means that there is no new cooling load, and the cooling state is such that power can be saved by the reduction in the next second reduction step. If not, the power saving in the first reduction stage can be performed because the new cooling load is loaded or the outside air temperature is high, but the power saving is performed up to the second reduction stage. It is in a cooling state that cannot do it.

In step SP9, the rotation speed Rs21 of the blower 21A is reduced to a predetermined value B1, for example, 50 rpm, to 2650 rpm, so that the refrigerator 7
After reducing the amount of circulation of the cool air in the next step SP1,
Move to 0. That is, here, from the first reduction stage to the second reduction stage,
This means that the state has shifted to the power saving state in the reduction stage.

In step SP10, the standby time Tb,
For example, after waiting for a time corresponding to three operation cycles Tz, the process proceeds to the next step SP11. Other items are the same as those described in step SP3.

In step SP11, it is determined whether or not the operating rate Tr is equal to or less than a predetermined value X2, for example, 50% or less.
Go to step 14; otherwise, go to the next step SP1
Move to 2.

Here, when it is determined that it is equal to or less than the predetermined value X2, it means that there is no new cooling load, and the cooling state is such that the power can be saved by repeating the reduction in the second reduction stage. Otherwise, if a new cooling load is loaded, or because the outside air temperature is high, it is not possible to perform power saving until the reduction in the second reduction stage is repeated, or That is, the cooling state has to be returned to the state of the steady operation.

In step SP12, the rotation speed Rs21 of the blower 21A is increased by a predetermined value B1, for example, 50 rpm, and returned to 2700 rpm, thereby returning the amount of circulation of cool air in the refrigerator 71 to the previous state. Thereafter, the flow shifts to the next step SP13.

In step SP13, step SP1
Similarly to 0, after waiting for the elapse of the standby time Tb, the process returns to step SP7. If it exceeds the predetermined value X2 in step SP7, it means that a new cooling load has been loaded,
Since the operation rate Tr has increased, the routine returns to the state of steady operation by the main control processing routine via step SP1.

In step SP14, in step SP9
It is determined whether or not the number of times the rotation speed Rs21 of the blower 21A has been repeatedly reduced has been repeated a predetermined number of times N2, for example, three times. If the number of times N2 has been repeated, the next step SP5 Otherwise, the process returns to step SP2.

Therefore, when the process proceeds to step SP15, three times of the predetermined value B1, for example, 50 rpm × 3
= 2550 rpm, which is a reduction of 150 rpm. Other items are the same as those described in step SP7.

In step SP15, it is determined whether or not the operating rate Tr is equal to or less than a predetermined value X3, for example, 45% or less. If the operating rate Tr is equal to or less than the predetermined value X3, the process proceeds to the next step SP16. Otherwise, step SP
Return to 12.

Here, when it is determined that it is equal to or less than the predetermined value X3, it means that there is no new cooling load, and the cooling state is such that power can be saved by the reduction in the next third reduction step. If not, the power saving in the second reduction step can be performed because a new cooling load is loaded or the outside air temperature is high, but the power saving up to the third reduction step is performed. It is in a cooling state that cannot do it.

In step SP16, the rotational speed Rs11 of the electric motor 11B is set to a predetermined value A2, for example, 420 rpm.
By reducing the pressure to 2400 rpm, the amount of compression in the compressor 10 is reduced, and the rotation speed Rs21 of the blower 21A is reduced to a predetermined value B2, for example, 850 rpm.
After performing both reductions at 1700 rpm to reduce the amount of circulating cold air in the refrigerator 71, the process proceeds to the next step SP17. That is, here, the state has shifted from the second reduction stage to the power saving state of the third reduction stage.

In step SP17, the standby time Tc
For example, after waiting for a time corresponding to three operation cycles Tz, the process proceeds to the next step SP18. Other items are the same as those described in step SP3.

In step SP18, it is determined whether or not the operating rate Tr is equal to or less than a predetermined value X2, for example, 50% or less.
21. If not, the next step SP1
Move to 9.

Here, when it is determined that it is equal to or less than the predetermined value X2, it means that there is no new cooling load, and the cooling state is such that power can be saved by the reduction in the next fourth reduction stage. If not, the power saving in the third reduction stage can be performed because the new cooling load is loaded or the outside air temperature is high, but the power saving up to the fourth reduction stage is performed. Or it is in a cooling state that needs to be returned to a state of steady operation.

At step SP19, the rotational speed Rs11 of the electric motor 11B is set to a predetermined value A2, for example, 420 rpm.
By increasing the pressure to 2400 rpm, the amount of compression in the compressor 10 is increased, and the rotation speed Rs21 of the blower 21A is increased to a predetermined value B2, for example, 85.
By increasing by 0 rpm and returning to 2550 rpm, after returning both the amount of compression and the amount of circulation of cool air in the refrigerator 71 to the previous state in the compression unit 10, the next step SP2
Move to 0.

{Circle around (2)} In step SP20, in step SP1
Similarly to 7, after waiting for the elapse of the standby time Tc, the process returns to step SP15. If the predetermined value X3 is exceeded in step SP15, it means that the operation rate Tr has increased because a new cooling load has been loaded, and the operation rate Tr has increased in step SP8.
-Return to the state of the steady operation by the main control processing routine through step SP1.

In step SP21, the rotational speed Rs11 of the electric motor 11B is reduced by a predetermined value A1, for example, 60 rpm to 2340 rpm, so that the compression amount in the compression unit 10 is reduced, and then the process proceeds to the next step SP22. I do. That is, here, the state has shifted from the third reduction stage to the power saving state of the fourth reduction stage.

In step SP22, the standby time Td,
For example, after waiting for a time corresponding to three operation cycles Tz, the process proceeds to the next step SP23. Other items are the same as those described in step SP3.

In step SP23, it is determined whether or not the operation rate Tr is equal to or less than a predetermined value X2, for example, 50% or less.
26, if not, the next step SP2
Move to 4.

Here, when it is determined that the value is equal to or less than the predetermined value X2, it means that there is no new cooling load, and the cooling state is such that the power can be saved by repeating the reduction in the fourth reduction stage. Otherwise, if a new cooling load is loaded, or because the outside air temperature is high, it is not possible to perform power saving until the reduction in the fourth reduction stage is repeated, or That is, the cooling state has to be returned to the state of the steady operation.

In step SP24, the rotational speed Rs11 of the electric motor 11B is increased by a predetermined value A1, for example, 60 rpm, and returned to 2400 rpm. To step SP6.

{Circle around (2)} in step SP25,
Similarly to 2, after waiting for the elapse of the standby time Td, the process returns to step SP18. If the predetermined value X2 is exceeded in step SP18, it means that the operation rate Tr has increased because a new cooling load has been loaded, and step SP1 is performed.
After step SP8 and step SP1, the operation is returned to the normal operation state by the main control processing routine.

{Circle over (SP)} in step SP2
It is determined whether the number of times the reduction of the rotation speed Rs11 of the motor 11B by 1 has been repeated has been performed a predetermined number of times N3, for example, three times, and if the number of times N3 has been performed, the next step is performed. The process proceeds to SP27, and if not, returns to step SP2.

Therefore, when the process proceeds to step SP27, three times of the predetermined value A1, for example, 60 rpm × 3
= 2220 rpm, which is a reduction of 180 rpm. Other items are the same as those described in step SP7.

In step SP27, it is determined whether or not the operating rate Tr is equal to or less than a predetermined value X3, for example, 45% or less. If the operating rate Tr is equal to or less than the predetermined value X3, the process proceeds to the next step SP28. Otherwise, step SP
Return to 24.

Here, when it is determined that it is equal to or less than the predetermined value X3, it means that there is no new cooling load, and the cooling state is such that power can be saved by the reduction in the next fifth reduction step. If not, the power saving in the fourth reduction step can be performed because a new cooling load is loaded or the outside air temperature is high, but the power saving is performed up to the fifth reduction step. It is in a cooling state that cannot do it.

In step SP28, the rotational speed Rs21 of the blower 21A is reduced to a predetermined value B1, for example, 50 rpm to 1650 rpm, so that the amount of circulating cool air in the refrigerator 71 is reduced.
Move to 29. That is, here, the state has shifted from the fourth reduction stage to the power saving state of the fifth reduction stage.

In step SP29, the standby time Te,
For example, after waiting for a time corresponding to three operation cycles Tz, the process proceeds to the next step SP30. Other items are the same as those described in step SP3.

In step SP30, it is determined whether or not the operating rate Tr is equal to or less than a predetermined value X3, for example, 45% or less.
33, if not, the next step SP3
Move to 1.

Here, when it is determined that the value is equal to or smaller than the predetermined value X3, it means that there is no new cooling load, and the cooling state is such that power can be saved by repeating the reduction in the fifth reduction stage. Otherwise, if a new cooling load is loaded, or because the outside air temperature is high, it is not possible to perform power saving that repeats the reduction in the fifth reduction stage, or That is, the cooling state has to be returned to the state of the steady operation.

In step SP31, the rotational speed Rs21 of the blower 21A is increased by a predetermined value B1, for example, 50 rpm, and returned to 1700 rpm, thereby returning the amount of circulation of cool air in the refrigerator 71 to the previous state. Thereafter, the flow shifts to the next step SP32.

{Circle around (2)} In step SP32, step SP2
Similarly to 9, after waiting for the elapse of the standby time Te, the process returns to step SP27. If the predetermined value X3 is exceeded in step SP27, it means that the operation rate Tr has increased because a new cooling load has been loaded, and the operation rate Tr has been increased in step SP2.
Step SP15 Step SP8 Step SP
The routine is returned to the state of steady operation by the main control processing routine through step 1.

{Circle over (SP)} in step SP2
It is determined whether the number of times the rotation speed Rs21 of the blower 21A has been reduced by the number 8 has been repeated a predetermined number of times N4, for example, three times. If the number of times N4 has been performed, the next step is performed. The process proceeds to SP34, and otherwise returns to step SP28.

Therefore, when proceeding to step SP34, three times of the predetermined value B1, for example, 50 rpm × 3
= 1550 rpm after a reduction of 150 rpm. Other items are the same as those described in step SP7.

In step SP34, it is determined whether or not the operating rate Tr is equal to or less than a predetermined value X3, for example, 45% or less. If the operating rate Tr is equal to or less than the predetermined value X3, the process proceeds to the next step SP35. Otherwise, step SP
Return to 31.

Here, when it is determined that it is equal to or less than the predetermined value X3, it means that there is no new cooling load, and the cooling state is such that power can be saved by the reduction in the next sixth reduction step. If not, the power saving in the fifth reduction stage can be performed because the new cooling load is loaded or the outside air temperature is high, but the power saving is performed up to the sixth reduction stage. It is in a cooling state that cannot do it.

In step SP35, the rotational speed Rs11 of the electric motor 11B is set to a predetermined value A2, for example, 420 rpm.
By reducing it to 1800 rpm, the amount of compression in the compression unit 10 is reduced, and the rotation speed Rs21 of the blower 21A is reduced to a predetermined value B3, for example, 1050 rpm.
m and then to 500 rpm to reduce both the amount of circulating cold air in the refrigerator 71 and then proceed to the next step SP36. That is, here, it has shifted from the fifth reduction stage to the power saving state of the sixth reduction stage.

In step SP36, the standby time Tf,
For example, after waiting for a time corresponding to three operation cycles Tz, the process proceeds to the next step SP37. Other items are the same as those described in step SP3.

In step SP37, it is determined whether or not the operation rate Tr is equal to or less than a predetermined value X3, for example, 45% or less. If it is less than 45%, this step SP37 is repeated. Otherwise, the procedure moves to the next step SP38.

Here, when it is determined that it is equal to or less than the predetermined value X3, it means that there is no new cooling load, and the cooling state is such that power saving by the reduction in the sixth reduction stage can be continued. If it is determined that it is not, the power saving operation up to the fifth reduction stage can be performed because a new cooling load is loaded or the outside air temperature is high.
Either a cooling state in which power saving in the reduction stage cannot be performed or a cooling state in which it is necessary to return to a steady operation.

In step SP38, the rotational speed Rs11 of the electric motor 11B is set to a predetermined value A2, for example, 420 rpm.
By returning to the previous 2220 rpm, the amount of compression in the compressor 10 is increased, and the rotation speed Rs21 of the blower 21A is increased to a predetermined value B3, for example, 10 rpm.
By increasing by 50 rpm and returning to 1550 rpm, the compression unit 10 returns both the amount of compression and the circulation amount of cool air in the refrigerator 71 to the previous state, and then returns to the next step SP
Move to 39.

{Circle over (SP)} in step SP3
Similarly to 6, after waiting for the elapse of the standby time Tf, the process returns to step SP33. If the predetermined value X3 is exceeded in step SP33, it means that the operating rate Tr has increased because a new cooling load has been loaded, and the operation rate Tr has increased in step SP2.
7. Step SP18, Step SP8, Step SP
The routine is returned to the state of steady operation by the main control processing routine through step 1.

[Modification] The present invention includes the following modifications. (1) It is configured by applying to the configuration of the second prior art of FIG.
In this case, the operation of the compressor 10 and the blower 21A is controlled based on the data based on the detection signal of the temperature detector S2. Adjustment of the flow adjustment unit 80, for example, the damper 81
Is controlled based on data based on a detection signal of the temperature detector S1.

(2) The cooling target 70 is applied to a configuration in which a refrigerator is used instead of the refrigerator 71. (3) One or both of the components of the electric motor 11B and the variable frequency circuit 51 and the components of the electric motor (not shown) and the variable frequency circuit (not shown) of the blower 21A,
The [AC type / cyclo converter type configuration] of FIG. 5 or the [DC type / inverter type configuration] [AC type / inverter type configuration] of FIG. 5 is changed to a single phase configuration.

(4) Each predetermined value in [power saving operation configuration] in FIG. 1 is changed to an appropriate value. (5) The number of reduction steps in the [power saving operation configuration] of FIG. 1 is changed to an appropriate number.

(6) The reduction steps in the [power saving operation configuration] of FIG. 1 include, for example, a first reduction step and a second reduction step.
As in the fourth stage and the fifth stage, instead of the configuration of the reduction stage in which the amount of cooling air in the refrigerator is reduced after the reduction of the amount of compression in the compression unit is preceded, the circulation of cold air in the refrigerator is performed. The operation configuration is changed to a combination in which the compression amount in the compression section is reduced after the reduction of the amount is prioritized.

(7) The reduction stage in [power saving operation configuration] in FIG. 1 is changed, for example, to the first reduction stage / second reduction stage or the fourth stage / fifth stage, or as described in (6) above. All the reduction stages are combined with only the reduction stages that alternately reduce the amount of compression in the compression section and the amount of cool air circulating in the refrigerator.

(8) The reduction stages in the [power saving operation configuration] of FIG. 1 include, for example, a reduction in the amount of compression in the compression section and a circulation of cool air in the refrigerator, as in a third reduction stage and a sixth reduction stage. All the reduction steps are configured by combining only the reduction steps in which the reduction of the amount is performed in one reduction step.

(9) In order to prevent a transient operation cycle at the start of the operation of the apparatus as shown at the left end of the operation diagram of FIG. An operation cycle Tz, for example, a period corresponding to 10 cycles is configured not to shift to a control process such as the control process flow of FIG.

(10) Each predetermined value required for each control can be changed to an appropriate predetermined value by operating an operation section such as the setting operation section 66. (11) Each control or a part of the control is configured to be performed by a switching operation using a circuit configuration set to perform an operation according to each predetermined value and a discrete switching circuit configuration.

[0127]

According to the present invention, the operation rate is monitored,
To reduce the amount of compression in the compression unit, for example, by reducing the rotation speed of the electric motor that drives the compression unit, and to reduce the amount of circulation of cool air in the refrigerator, for example, to reduce the rotation speed of the blower in the refrigerator. Is controlled by the control unit over a plurality of required steps, a rational power-saving operation can be performed in accordance with the cooling operation state in each case, so that an extremely convenient refrigeration apparatus can be provided.

[0128] Further, in the refrigeration apparatus provided with a variable frequency circuit, it is possible to provide a refrigerator capable of performing a power saving operation with an inexpensive configuration only by changing the control processing flow without adding a special mechanism. There are features such as being able to.

[Brief description of the drawings]

In the drawings, FIGS. 1 and 2 show an embodiment of the present invention, and FIGS.
7 show the prior art, and the contents of each figure are as follows.

FIG. 1 is an overall block configuration and operation diagram of main parts.

FIG. 2 is a main part control processing flowchart.

FIG. 3 is an overall block diagram.

FIG. 4 is an overall block diagram.

FIG. 5 is a block diagram of a main part.

FIG. 6 is a block diagram of a main part.

FIG. 7 is an operation configuration diagram of a main part.

[Explanation of symbols]

 REFERENCE SIGNS LIST 1 AC power supply 1a 3-phase AC power supply 2 Rectifier circuit 10 Compressor 10a Compressor refrigerant 11A Compression mechanism 11B Electric motor 11B1 Synchronous motor 11B2 Three-phase synchronous motor 20 Evaporator 20a Refrigerant 21 Heat exchanger 21A Blower 30 Decompressor 30a Depressurized refrigerant 31 Capillary Tube 40 Condensing unit 40a Condensed refrigerant 41 Heat exchanger 41A Blower 50 Compression amount adjusting unit 51 Variable frequency circuit 51A Inverter circuit 51B Control circuit 51B1 Control circuit 51B2 Control circuit 51B3 Control circuit 51C Cycloconverter 51X Variable frequency converter 60 Control unit 60ACPU Reference Signs List 61 input / output port 62 processing memory 63 working memory 64 data memory 65 clock circuit 70 cooling target 71 refrigerator / refrigerator / freezer 71A freezer 71B refrigerator 72 partition wall 73 partition wall 0 flow adjustment portion 81 damper 85 inner wall 100 refrigerator DL DC reactor FL field coil PS rotor position detector S1 temperature detector S2 temperature detector SY1 thyristor SY2 thyristor SY3 thyristor RT rotor

Claims (5)

[Claims] 1. A cooling operation for cooling an object to be cooled by a compressed refrigerant obtained by compressing the refrigerant in a compression unit,
A refrigeration apparatus configured to circulate cool air in a refrigerator to be cooled, wherein, when an operation rate of the cooling operation is equal to or less than a predetermined value, the amount of compression of the refrigerant in the compression unit and the circulation of the cool air. A refrigeration apparatus comprising control means for performing control for reducing one or both of the amounts. 2. The method according to claim 1, wherein the compression rate of the refrigerant is reduced when the operation rate becomes equal to or less than a first predetermined value, and the operation rate becomes equal to or less than a second predetermined value smaller than the first predetermined value. 2. The refrigeration apparatus according to claim 1, wherein the amount of circulation of the cool air is reduced when the refrigeration is performed. 3. The method according to claim 1, wherein when the operation rate is equal to or less than a first predetermined value, the amount of compression of the refrigerant is reduced, and the operation rate is equal to or less than a second predetermined value smaller than the first predetermined value. When the operating rate becomes equal to or less than a third predetermined value that is smaller than the second predetermined value, a reduction in the amount of compression of the refrigerant and a reduction in the amount of circulation of the cold air are performed. The refrigeration apparatus according to claim 1, wherein reduction is performed. 4. The method according to claim 1, wherein when the operation rate is equal to or less than a first predetermined value, the amount of compression of the refrigerant is reduced, and the operation rate is equal to or less than a second predetermined value smaller than the first predetermined value. When the operating rate becomes equal to or less than a third predetermined value that is smaller than the second predetermined value, a reduction in the amount of compression of the refrigerant and a reduction in the amount of circulation of the cold air are performed. The refrigeration apparatus according to claim 1, wherein a plurality of stepwise reductions are performed. 5. The method of reducing the amount of compression of the refrigerant by reducing the rotation speed of an electric motor that drives the compression unit, and reducing the amount of circulation of the cool air by reducing the rotation speed of a blower that circulates the cool air. Claims 1 and 2, characterized in that
The refrigeration apparatus according to claim 3 or 4.