JP2007093057A - Refrigerator and its control method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a refrigerator with a circuit having simple construction for applying proper DC voltage on DC loads having different rated voltage. <P>SOLUTION: The refrigerator comprises the plurality of DC loads 9-13 to be operated with the application of predetermined rated voltage thereto, and the voltage variable DC power circuit α having variable output voltage for applying DC voltage thereto. A control part 7 controls the output voltage of the voltage variable DC power circuit α depending on the rated voltage of one or more DC loads to be operated while prohibiting the simultaneous operation of any of the plurality of DC loads 9-13, having different rated voltage. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a refrigerator having a plurality of DC loads and a control method thereof, and more particularly, a refrigerator suitable for simply configuring a circuit that applies an appropriate DC voltage to DC loads having different rated voltages and the control thereof. It is about the method.

The refrigerator has a plurality of direct current loads that operate by applying a predetermined rated voltage, for example, a fan driving motor that blows cold air, and cold air to a cooling chamber in which an object to be cooled such as food is stored. A motor for driving a damper for adjusting the supply amount of ice, a motor for deicing in an automatic ice making device, a water supply motor in an automatic ice making device, a motor for driving a refrigerant flow control valve in a refrigeration cycle, etc. are provided. Some have different rated voltages.
In a conventional refrigerator, a constant voltage DC power supply circuit (hereinafter referred to as a constant voltage power supply) having a constant output voltage is provided, and a voltage drop element or a voltage conversion circuit is connected to a power supply line from the constant voltage power supply to each DC load. Thus, an appropriate voltage (rated voltage) is applied to each DC load. Generally, the output voltage of a constant voltage power supply is set to the maximum voltage among the rated voltages of a plurality of DC loads. For specific DC loads with different rated voltages, the voltage drop for each specific DC load An element or the like is often provided.
For example, Patent Document 1 discloses a refrigerator in which a voltage drop element is provided between a switching power supply transformer (constant voltage power supply) and a driving circuit of a stepping motor that drives a damper for adjusting the amount of cool air supply. .
JP 2004-12028 A

However, when the number of specific DC loads whose rated voltage is different from the output voltage of the constant voltage power supply is large, it is necessary to provide a voltage drop element and a voltage conversion circuit for each specific DC load, which increases the number of parts and costs. In addition, there is a problem that the area of the board on which the component is mounted increases and the volumetric efficiency of the refrigerator (the ratio of the storage volume of food and the like to the total volume of the refrigerator) deteriorates.
In addition, when a common voltage drop element or voltage conversion circuit is provided for each DC load having the same rated voltage in order to reduce the number of components constituting the voltage drop element or voltage conversion circuit, the voltage drop element or voltage conversion circuit As a result, the wiring pattern on the substrate forming the power supply line extending from the power supply to each of the DC loads becomes long, and the supply voltage is lowered or susceptible to noise, which increases the possibility of malfunction. In addition, voltage drop elements and voltage conversion circuits that are commonly provided for a plurality of DC loads must use elements / components having an electric capacity (rated capacity) that can drive all the DC loads to be driven. In addition, there is a problem that the size of the component is increased and the cost is increased.
Accordingly, the present invention has been made in view of the above circumstances, and its object is to provide a refrigerator that can simply configure a circuit that applies an appropriate DC voltage to DC loads having different rated voltages, and a control method thereof. Is to provide.

In order to achieve the above object, the present invention is applied to a refrigerator having a plurality of DC loads that operate by applying a predetermined rated voltage, and a DC voltage is applied to the plurality of DC loads. A voltage variable DC power supply circuit that outputs (outputs) and has a variable output voltage, and voltage control means that controls the output voltage of the voltage variable DC power supply circuit according to the rated voltage of the DC load to be operated. It is prepared for.
Thereby, it is not necessary to provide a voltage drop element or a voltage conversion circuit for each DC load having a different rated voltage, and a circuit for applying an appropriate DC voltage to each DC load having a different rated voltage can be simply configured.
In this case, during operation of the DC load having a certain rated voltage, it is conceivable to include an operation prohibiting means for prohibiting the operation of all or a part of the DC loads having a different rated voltage.
In addition, when operating a second DC load having a higher priority and a different rated voltage with respect to the first DC load during operation of the first DC load of a certain rated voltage, Interrupt control means for interrupting operation and interrupting and operating the second DC load having a high priority is provided, and the voltage control means performs the interrupt control according to the rated voltage of the DC load operated by the interrupt control means. One that controls the output voltage of the voltage variable DC power supply circuit is also conceivable.
Further, it is preferable that there is no waste if the maximum output voltage of the voltage variable DC power supply circuit is set to the maximum voltage among the rated voltages of the plurality of DC loads.

Here, as the plurality of DC loads, for example, a motor for driving a fan that blows cool air, a motor for driving a damper that adjusts the amount of cool air supplied to the cooling chamber, a motor for deicing in an automatic ice making device, an automatic A water supply motor in an ice making device, a motor for driving a refrigerant flow path control valve in a refrigeration cycle, and the like are conceivable, and one or more of these are included in the plurality of DC loads.
In particular, since a motor for driving a damper for adjusting the amount of cold air supplied to the cooling chamber is provided for each cooling chamber, the present invention is applied to a refrigerator having a large number of cooling chambers when the motor for driving the damper is a DC load. Then, the effect of reducing the number of parts and improving the housing efficiency becomes more remarkable.
Moreover, this invention can also be grasped | ascertained as the control method of a refrigerator in which the function of the refrigerator shown above is implement | achieved.
That is, a plurality of DC loads that operate by applying a predetermined rated voltage, and a voltage variable DC power supply circuit that applies a DC voltage to the plurality of DC loads and has a variable output voltage. A control method for a refrigerator, wherein a load selection step of selecting one or a plurality of DC loads to be operated while prohibiting simultaneous operation of a plurality of DC loads having different rated voltages, and the load selection step And a voltage control step of controlling an output voltage of the voltage variable DC power supply circuit according to a selected rated voltage of the DC load.
Thereby, the same effect as the refrigerator mentioned above is acquired.

  According to the present invention, since the output voltage of the voltage variable DC power supply circuit is controlled according to the rated voltage of the DC load to be operated, there is no need to provide a voltage drop element or a voltage conversion circuit for each DC load having a different rated voltage, A circuit that applies an appropriate DC voltage to each DC load having a different rated voltage can be simply configured. As a result, the number of parts can be reduced and the housing efficiency can be improved as compared with the prior art.

Embodiments of the present invention will be described below with reference to the accompanying drawings for understanding of the present invention. In addition, the following embodiment is an example which actualized this invention, Comprising: It is not the thing of the character which limits the technical scope of this invention.
FIG. 1 is a block diagram showing the configuration of the main part of the refrigerator X according to the embodiment of the present invention, and FIG. 2 is a flowchart showing the output voltage control procedure of the voltage variable DC power supply circuit α in the refrigerator X. .

The refrigerator X according to the embodiment of the present invention includes a plurality of DC loads that operate when a predetermined rated voltage is applied thereto, and a DC power supply circuit that applies a DC voltage to these DC loads varies in output voltage. The output voltage of the power supply circuit is controlled according to the rated voltage of the DC load to be operated.
First, the structure of the main part regarding the present invention in the refrigerator X will be described with reference to the block diagram shown in FIG.
As illustrated in FIG. 1, the refrigerator X includes a voltage variable DC power supply circuit α (hereinafter referred to as a variable pressure power supply circuit) and a plurality of DC loads 9 to 13 that operate by applying a predetermined rated voltage. Drive circuits 14 to 18 provided for each of them, a microcomputer for performing various controls in the refrigerator X, and a control unit 7 including a ROM or the like in which a control program executed by the microcomputer is stored. It is roughly structured.
In addition, although the refrigerator X is also provided with the other various components with which a common refrigerator is provided, since it does not make the characteristic of this invention, description is abbreviate | omitted here.

The variable voltage power supply circuit α includes a diode bridge circuit 1, an electrolytic capacitor 2, a switching IC 3, a switching transformer 4, a smoothing circuit 5, and a constant voltage control circuit 6, and the primary side (input side) is an AC power source G (commercial power source). The secondary side (output side) is connected in parallel to the plurality of DC loads 9 to 13 via the drive circuits 14 to 18.
The AC electricity supplied from the AC power supply G is full-wave rectified by the diode bridge circuit 1, smoothed by the electrolytic capacitor 2, and then subjected to switching processing by the switching IC 3 (switching circuit). The switching output from the switching IC 3 is subjected to voltage conversion at a constant voltage ratio by the switching transformer 4 and then smoothed by the smoothing circuit 5 to become a DC voltage Vo. The DC output voltage from the smoothing circuit 5, that is, the output voltage Vo of the variable voltage power supply circuit α is input to the constant voltage control circuit 6, and the difference between the output voltage Vo and the set voltage Vs set in the constant voltage control circuit 6. The signal is fed back to the switching IC 3. Thus, a stable power supply circuit (switching power supply circuit) is configured in which the output voltage Vo is maintained at the set voltage Vs regardless of the magnitude of the current flowing from the variable voltage power supply circuit α to the DC loads 9 to 13.
Here, the voltage control signal 21 output from the control unit 7 is input to the constant voltage control circuit 6, and the set voltage Vs is set according to the level of the voltage control signal 21. That is, the variable voltage power supply circuit α applies a DC voltage to the plurality of DC loads 9 to 13 and has a variable voltage type in which the output voltage is variable by changing the level of the voltage control signal 21 input from the outside. DC power supply circuit.

The control unit 7 outputs a voltage control signal 21 to the constant voltage control circuit 6, thereby controlling a voltage control function for controlling the output voltage of the variable voltage power circuit α and an operation control signal for the drive circuits 14 to 18. 22 is provided with various control functions such as a load control function for controlling the operation / stop of each of the DC loads 9 to 13. These control functions are realized when a microcomputer included in the control unit 7 executes a predetermined control program.
The control unit 7 is supplied with electricity obtained by converting the output voltage Vo of the variable voltage power supply circuit α into a predetermined voltage (usually DC 5 V) by the voltage conversion circuit 8. The voltage supplied from the voltage conversion circuit 8 to the control unit 7 is constant regardless of the change in the output voltage Vo of the variable voltage power supply circuit α.

Next, each DC load 9-13 is demonstrated.
FIG. 1 shows a damper motor 9, a fan motor 10, an ice removing motor 11, a water supply motor 12, and a refrigerant valve motor 13 as examples of DC loads.
The fan motor 10 is a motor provided for driving a cooling fan that forcibly blows cold air generated by heat exchange in an evaporator provided in a refrigerating cycle (not shown) to a cooling chamber in which an object to be cooled such as food is stored. It is.
The damper motor 9 is a motor provided for driving a damper that distributes the cool air sent by the cooling fan to each of the plurality of cooling chambers and adjusts the distribution amount (the amount of cool air supplied to the cooling chamber). For example, it is constituted by a stepping motor. By controlling the rotation angle of the damper motor 9, the opening / closing angle of the baffle provided in the damper is controlled, and the supply amount (distribution amount) of cold air to the cooling chamber is adjusted. A plurality of damper motors 9 are provided for each of the plurality of cooling chambers.
The ice removal motor 11 and the water supply motor 12 constitute an automatic ice making device (not shown). The automatic ice making device supplies water from a predetermined water supply tank to an ice tray by a water supply pump driven by a water supply motor 12, and after the water in the ice tray becomes ice, the ice making motor 11 releases the ice from the ice tray. It is a device that drops the ice into a predetermined ice container. Since the mechanism of the automatic ice making apparatus is well known, a detailed explanation is omitted here.
The refrigerant valve motor 13 is a motor provided for driving a refrigerant flow control valve (refrigerant valve) provided at a branch portion of a refrigerant path (refrigerant pipe) in a refrigeration cycle (not shown). It is composed of a motor.
Each of the DC loads 9 to 13 is supplied (applied) with the output voltage Vo of the variable voltage power supply circuit α according to the operation control signal 22 output from the control unit 7 by the drive circuits 14 to 18 provided corresponding to each of the DC loads 9 to 13. The operation / stop is controlled by switching the / shutoff.

Here, the DC loads 9 to 13 have different rated voltages. In the present embodiment, the rated voltage of the damper motor 9 is DC12V, the rated voltage of the fan motor 10 is DC15V, the rated voltage of the ice removing motor 11 and the water supply motor 12 is DC12V, and the rated voltage of the refrigerant valve motor 13 is DC15V. To do.
The drive circuit 15 of the fan motor 10 has a voltage conversion circuit, and the rated voltage (DC 15 V) of the fan motor 10 is applied. The voltage supplied (applied) to the fan motor 10 is the voltage conversion described above. Depending on the operating conditions of the refrigerator X, the circuit adjusts in the range of DC7V to 15V.
The maximum output voltage of the variable voltage power supply circuit α is set to the maximum voltage (here, DC15V) among the rated voltages of the plurality of DC loads 9 to 13.

Next, the procedure of the output voltage control of the variable pressure power supply circuit α in the refrigerator X will be described with reference to the flowchart shown in FIG. This output voltage control is realized by the control unit 7 (microcomputer) executing a predetermined control program. Note that S1, S2,... Shown below represent identification codes of processing procedures (steps).
When the refrigerator X is connected to the commercial power source G, after various initial settings (S1) are performed by the control unit 7, the DC load of the rated voltage is set for each level of the rated voltage in each of the DC loads 9 to 13. It is determined whether or not it is operating (S2, S3). In the present embodiment, it is determined whether or not the DC loads 10, 13 (hereinafter referred to as a rated 15V load) having a rated voltage of DC 15V are in operation (S2) and the DC loads 9, 11, Whether or not 12 (hereinafter referred to as a rated 12V load) is operating is determined (S3). Here, the determination as to whether or not each of the DC loads 9 to 13 is in operation is performed based on whether the state flag set (stored in the memory) for each of the DC loads 9 to 13 is ON or OFF. . This state flag is all set to OFF indicating the stop state at the time of the initial setting (S1), and thereafter, every time one of the DC loads is operated as described later, the state flag corresponding to the DC load is set. Is set to ON indicating the operating state.

In steps S2 and S3, when it is determined that the rated 15V load is operating (Y side of S2), or when any DC load is determined not to be operating (stopped) (in S3) On the N side, the control unit 7 determines whether it is necessary to additionally operate a new rated 15V load (S4).
Here, with respect to each of the DC loads 9 to 13 in parallel with the output voltage control process, the control unit 7 needs to operate or stop (end of operation) according to a predetermined control algorithm (control rule). This determination process is performed but is not shown in FIG.
In step S4, when it is determined that a new rated 15V load needs to be additionally operated, the control unit 7 outputs the voltage control signal 21 to the constant voltage control circuit 6 to thereby change the variable voltage power supply circuit α. The output voltage Vo is controlled to be 15V (S5), and the operation of the rated 15V load determined to be necessary for the additional operation is started (S6). This operation is started by outputting the operation control signal 22 to the corresponding drive circuit (15 or 18). Further, the control unit 7 sets the status flag to ON (operating) for the newly operated rated 15V load (DC load) (S7).

On the other hand, when it is determined in steps S2 to S4 that the rated 12V load is in operation (Y side of S3), or the rated 12V load is not in operation (all are stopped) and a new rating When it is determined that it is not necessary to additionally operate the 15V load, the control unit 7 determines whether it is necessary to additionally operate a new rated 12V load (S8).
When it is determined in step S8 that a new rated 12V load needs to be additionally operated, the control unit 7 outputs the voltage control signal 21 to the constant voltage control circuit 6 to thereby change the variable voltage power supply circuit α. Control is performed so that the output voltage Vo becomes 12V (S9), and operation of a rated 12V load that is determined to be required to be additionally operated is started (S10). This operation is started by outputting an operation control signal 22 to the corresponding drive circuit (any one of 14, 16 and 17). Further, the control unit 7 sets the status flag to ON (in operation) for the newly operated rated 12V load (DC load) (S11).

In addition, after the operation of a new DC load is started by the processing of steps S5 to S7 or steps S9 to S11, or when the operation of a new DC load is not performed, the control unit 7 A determination process (S12) is performed as to whether or not it is necessary to end (stop) the operation of the DC load. As described above, the operation / stop (operation end) timing of each DC load is determined based on a predetermined control algorithm (control rule).
If it is determined that there is a DC load that needs to be terminated, the control unit 7 stops the operation of the DC load (S13), and further turns off the status flag of the DC load (stopped). ) (S14), the process proceeds to step S2. On the other hand, if it is determined that there is no DC load that needs to be terminated, the control unit 7 proceeds to step S2 as it is. Thereby, the process after step S2 mentioned above is repeated.

By performing the processing shown in FIG. 2, the control unit 7 sets the output voltage Vo of the variable voltage power supply circuit α to 15V or 12V depending on the rated voltage (DC15V or DC12V) of the DC load to be operated. (S5, S9, an example of voltage control means).
Further, in the process shown in FIG. 2, the control unit 7 operates the DC load (9, 11 or 12) having a different rated voltage (DC12V) during the operation of the DC load (10 or 13) whose rated voltage is DC15V. ) Is not executed (S9 to S11). Similarly, during operation of a DC load (9, 11 or 12) with a rated voltage of DC12V, processing (S5 to S7) is performed to operate a DC load (10 or 13) with a different rated voltage (DC15V). do not do.
As described above, the control unit 7 selects one or a plurality of DC loads to be operated by the processes of Steps S4 and S8 while prohibiting the simultaneous operation of the DC voltages 9 to 13 having different rated voltages ( An example of a load selection process), and the output voltage Vo of the variable voltage power supply circuit α is controlled by the processes of steps S5 and S9 according to the rated voltage of the selected DC load (an example of a voltage control process).
In other words, the control unit 7 prohibits the operation of the DC load having a different rated voltage during the operation of the DC load having a certain rated voltage (an example of the operation prohibiting unit) during the operation of the DC load having a certain rated voltage.
Thus, a voltage (appropriate) suitable for each rated voltage is applied to each DC load without providing a voltage drop element or a voltage conversion circuit for each DC load. In addition, the prohibition of the operation of the DC load is the case where the operation is prohibited for all or some of the DC loads having a rated voltage different from the operating DC load among the DC loads included in the refrigerator X. It is possible to prohibit this.

In the embodiment described above, an example of performing control for prohibiting the operation of the DC load having a different rated voltage during the operation of the DC load having a certain rated voltage has been described. However, the present invention is not limited to this.
For example, for each of the DC loads 9 to 13, priorities are set in advance and stored in storage means such as a ROM that can be read by the control unit 7, and a DC load with a certain rated voltage (this is designated as the first DC load). Operation of a DC load having a higher priority and a different rated voltage than the first DC load (referred to as a second DC load) is required. When the control unit 7 executes control for interrupting the operation of the first DC load during the operation and interrupting the operation of the second DC load having a higher priority (operation of the interrupt control means) An example) is also conceivable.
In this case, the control unit 7 controls the output voltage Vo of the variable voltage power supply circuit α in accordance with the rated voltage of the DC load operated by the interruption (in accordance with the rated voltage of the second DC load).
As a result, it is possible to avoid a situation in which a DC load with a high priority is kept waiting until the operation of a DC load with a low priority that has been operating first stops, and more appropriate DC load control can be performed.

Hereinafter, an example in which the control of the DC load based on the priority is applied to the processing procedure shown in FIG. 2 will be described.
For example, if it is determined in step S2 that a rated 15V load is in operation (Y side of S2), whether or not an additional operation of a rated 12V load is required by the control unit 7 as in step S8. If there is a rated 12V load that is determined to require additional operation, the priority is compared with the priority of the rated 15V load currently in operation. When it is determined that the operation of the rated 12V load having a higher priority than the rated 15V load currently being operated is necessary, the operation of the currently rated 15V load is interrupted and the status flag is turned OFF. After being set to (stopped), the control is performed so that the output voltage Vo of the variable voltage power supply circuit α becomes 15 V in the same manner as the processing of steps S5 to S7, and the operation start and the state of the rated 12V load with high priority are started. After the flag is set to ON (in operation), the process proceeds to step S12.

Similarly, when it is determined in step S3 that the rated 12V load is in operation (Y side of S3), is the controller 7 required to newly add a rated 15V load as in step S4? When there is a rated 15V load that is determined to require additional operation, the priority is compared with the priority of the rated 12V load that is currently operating. If it is determined that the operation of the rated 15V load having a higher priority than the rated 12V load that is currently operating is necessary, the operation of the rated 12V load that is currently operating is interrupted, and the status flag is turned OFF. After being set to (stopped), the control is performed so that the output voltage Vo of the variable voltage power supply circuit α becomes 12 V in the same manner as the processing of steps S9 to S11, and the operation start and the state of the rated 15V load having a high priority are performed. After the flag is set to ON (in operation), the process proceeds to step S12.
2 is added to the process shown in FIG. 2, and when the high-priority DC load interrupted by the processes in steps S12 to S14 is stopped, steps S5 to S7 or steps S9 to S9 are performed. The operation of the DC load whose operation has been interrupted by the processing of S11 is resumed.
Thereby, the operation control of the DC load according to the priority is performed. Such a control form is also an example of an embodiment of the present invention.

    The present invention can be used for a refrigerator.

The block diagram showing the structure of the principal part regarding this invention of the refrigerator X which concerns on embodiment of this invention. The flowchart showing the output voltage control procedure of the voltage variable DC power supply circuit α in the refrigerator X.

Explanation of symbols

X ... Refrigerator α ... Voltage variable DC power supply circuit (variable pressure power supply circuit)
DESCRIPTION OF SYMBOLS 1 ... Diode bridge circuit 2 ... Electrolytic capacitor 3 ... Switching IC
DESCRIPTION OF SYMBOLS 4 ... Switching transformer 5 ... Smoothing circuit 6 ... Constant voltage control circuit 7 ... Control part 8 ... Voltage conversion circuit 9 ... Damper motor (DC load)
10 ... Fan motor (DC load)
11 ... Ice motor (DC load)
12 ... Water supply motor (DC load)
13 ... Refrigerant valve motor (DC load)
14 to 18: Driving circuit 21: Voltage control signal 22: Operation control signals S1, S2,... Processing procedure (step)

Claims (6)

A refrigerator including a plurality of DC loads that operate by applying a predetermined rated voltage each,
A voltage variable DC power supply circuit that applies a DC voltage to the plurality of DC loads and has an output voltage variable;
Voltage control means for controlling the output voltage of the voltage variable DC power supply circuit according to the rated voltage of the DC load to be operated;
The refrigerator characterized by comprising.   2. The refrigerator according to claim 1, further comprising operation prohibiting means for prohibiting the operation of all or a part of the DC loads having a different rated voltage during operation of the DC load having a certain rated voltage. . When operating a second DC load having a higher priority and a different rated voltage than the first DC load during operation of the first DC load having a certain rated voltage, the operation of the first DC load is performed. Interrupt control means for interrupting and operating the second DC load is provided;
The refrigerator according to claim 1, wherein the voltage control unit controls an output voltage of the voltage variable DC power supply circuit according to a rated voltage of the DC load operated by the interrupt control unit.   The refrigerator according to any one of claims 1 to 3, wherein a maximum output voltage of the voltage variable DC power supply circuit is set to a maximum voltage among rated voltages of the plurality of DC loads.   A motor for driving a fan for blowing cool air to the plurality of DC loads, a motor for driving a damper for adjusting the amount of cool air supplied to the cooling chamber, a motor for removing ice in an automatic ice making device, and a motor for supplying water in an automatic ice making device The refrigerator in any one of Claims 1-4 in which one or more of the motors for a drive of the flow-path control valve of the refrigerant | coolant in a refrigerating cycle are included. A refrigerator including a plurality of DC loads that operate by applying predetermined rated voltages, and a voltage variable DC power supply circuit that applies a DC voltage to the plurality of DC loads and has a variable output voltage. Control method,
A load selection step of selecting one or a plurality of the DC loads to be operated while prohibiting simultaneous operation of the DC voltages having different rated voltages from the plurality of DC loads;
A voltage control step of controlling an output voltage of the voltage variable DC power supply circuit in accordance with a rated voltage of the DC load selected in the load selection step;
The control method of the refrigerator characterized by comprising.

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