JP2008008558A - Refrigerating unit - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a refrigerating unit capable of cooling uniformly the whole cooled space by respective refrigerating units, by preventing cooling operations from interfering each other in the plurality of refrigerating units provided in the cooled space. <P>SOLUTION: This refrigerating unit is provided with refrigeration cycle equipment such as a compressor driven speed-variably by an inverter, a condenser, a pressure reducer, an evaporator and a blower, and a controller for controlling a temperature sensor, a temperature setter and the refrigeration cycle equipment, the controller is provided with a setting means for setting the refrigerating unit to either of a master unit or a slave unit, and an input and output terminal, controls a speed of the compressor, based on a difference between a detected temperature from the temperature sensor and a set temperature from the temperature setter, when set to the master unit, and outputs operation data expressing the detected temperature and the set temperature from the input and output terminal. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a refrigeration apparatus for cooling a large storage such as a food product.

  In order to manage the space to be cooled, for example, a large storage such as food, at an appropriate temperature, it is necessary to install a refrigeration apparatus having a large cooling capacity. Although there is an idea to install one refrigeration unit with a sufficiently large cooling capacity according to the size of the storage, in this case, the refrigeration unit becomes larger and only the vicinity of the refrigeration unit installation location is locally It will be cooled, and it is difficult to cool the entire storage uniformly.

  As a means for uniformly cooling the entire storage, it is conceivable to prepare and install small refrigeration apparatuses corresponding to the size of the storage. However, in this case, depending on the installation position of each refrigeration apparatus, the cooling operation of each refrigeration apparatus interferes with each other, and as a result, there is a problem that proper temperature management in the storage becomes difficult.

  As a countermeasure, it is conceivable to adopt a method of synchronizing on / off operations of a plurality of installed refrigeration apparatuses.

  As an example of cooling the cooled space with a plurality of devices, a plurality of outdoor units and a plurality of indoor units are connected by a single refrigerant pipe to form a single refrigeration cycle. There is a technique for controlling the entire cycle and continuing control by using a specific slave unit as a master unit when the master unit fails (for example, Patent Document 1). This is because the master unit controls the control in a single refrigeration cycle, and does not air-condition a single cooled space by a plurality of refrigeration apparatuses each having a refrigeration cycle.

In addition, as an example of cooling the cooled space with multiple devices, multiple cold / hot water generators are connected in parallel, and if any of the cold / hot water generators malfunctions, cold / hot water that is operating normally is generated. There is a system control device that corrects the set temperature of the device and continues operation (for example, Patent Document 2). In this case, the system does not back up the chilled / hot water generators that are abnormal due to the individual control of multiple chilled / hot water generators, and the system controller controls the operation of all connected chilled / hot water generators. There is a problem that a new system control device is required for overall control separately from individual devices.
JP 2000-18684 A JP-A-9-170841

  The above-described method for synchronizing the on / off operation of a plurality of refrigeration units can solve the problem in the case of a refrigeration unit using a constant speed compressor controlled by on / off. In the case of a refrigeration apparatus with an inverter that is driven at a variable speed, it is necessary to control not only on / off but also the output frequency of the inverter, and it is not enough to synchronize on / off. Then, although the proposal which synchronizes the output frequency of an inverter is also considered, control becomes complicated.

  In addition, as a means for uniformly cooling the entire storage, prepare multiple refrigeration units with different cooling capacities, and install a refrigeration unit with a large cooling capacity at places with high cooling loads, such as the entrance of the storage. There is also an example of installing a refrigeration device with a small cooling capacity in a place where the cooling load is low, such as in the back of the storage, and when installing refrigeration devices with such different capacities, the output frequency of the inverter is made the same In some cases, the frequency is not appropriate. For example, if the rated frequency of one refrigeration unit is different from the rated frequency of the other refrigeration unit, when one is operating at the rated frequency, the other is not rated, and an imbalance occurs between the units. Proper temperature control inside becomes difficult.

  The present invention takes the above circumstances into consideration, and its purpose is to make the entire cooling space uniform by each refrigeration device without the cooling operations of a plurality of refrigeration devices provided in the cooling space interfering with each other. It is to provide a refrigeration apparatus that can be cooled.

  A refrigeration apparatus according to a first aspect of the present invention includes a refrigeration cycle device such as a compressor, a condenser, a decompressor, an evaporator, and a blower that are variable speed driven by an inverter, a temperature sensor, a temperature setting device, and the refrigeration cycle device. A control device for controlling is provided. The control device includes setting means for setting the refrigeration device to either the parent device or the child device, and an input / output terminal. When the control device is set to the parent device, the temperature detected by the temperature sensor and the temperature setting device are set. The speed of the compressor is controlled based on the difference from the set temperature, and operation data representing the detected temperature and set temperature is output from the input / output terminal. In addition, when the control device is set to the slave unit, the control device reads the detected temperature and the set temperature from the operation data output from the master unit and input to the input / output terminal, and based on the difference between the detected temperature and the set temperature. Control the speed of the compressor.

  According to the refrigeration apparatus of the present invention, the entire cooling space can be uniformly cooled by each refrigeration apparatus without the cooling operations of the plurality of refrigeration apparatuses provided in the cooling space interfering with each other.

  Hereinafter, an embodiment of the present invention will be described with reference to the drawings.

  As shown in FIG. 1, a plurality of refrigeration apparatuses 1, 2, 3, 4 are sequentially connected by a signal cable 5. These refrigeration apparatuses 1, 2, 3, and 4 have a compressor 11, a condenser 13, an evaporator unit 15, a control device 30, and the like, and are dispersed on a ceiling surface of a large storage such as a space to be cooled, such as a food warehouse. Each of them is sucked and cooled by the air in the storage, and the cooled air is blown out into the storage.

  The control device 30 of each refrigeration apparatus includes input / output terminals 1a, 2a, 3a, and 4a shown in FIG. These input / output terminals are R, S, T terminals connected to the three-phase AC power supply 10, No. 1 and No. 2 terminals for alarm signal output, and No. 3 to which the data signal line 6 in the signal cable 5 is connected. -It has the 4th terminal and the G terminal to which the ground wire 7 in the signal cable 5 is connected.

  The appearance and internal configuration of the refrigeration apparatus 1 are shown in FIGS. FIG. 3 is a view of the external appearance and the internal configuration of the main part from above, and FIG. 4 is a view of the external appearance and the internal configuration of the main part viewed from the side.

  That is, the substrate of the refrigeration apparatus 1 is mounted in an embedded state on the ceiling surface Ra of the storage R, and the compressor 11, the condenser 13, the condenser blower 14, the evaporator unit 15, and the control device 30 are mounted on the substrate. Yes. The condenser blower 14 has a drive motor 14 </ b> M and is disposed near the condenser 13. The evaporator unit 15 is provided at a position corresponding to the suction port 15a and the blowout port 15b formed in the substrate, and the evaporator 16 and the blowout port that are provided upright at a position between the suction port 15a and the blowout port 15b. It has an evaporator blower 17 disposed at a position corresponding to 15b. The evaporator blower 17 has a drive motor 17M, sucks in-compartment air through the suction port 15a and the evaporator 16, and blows out the air that has passed through the evaporator 16 from the blowout port 15b as cooling air. The cooling air blown out from the blowout port 15b is regulated in the blowout direction by the duct 18 mounted on the lower surface side of the substrate so as not to flow toward the suction port 15a.

  The refrigerant discharged from the compressor 11 is supplied to the condenser 13 through the high-pressure side pipe 12, and the refrigerant that has passed through the condenser 13 passes through the pipe (not shown) and the decompressor 20 described later to the evaporator unit 15. To the evaporator 16. The refrigerant having passed through the evaporator 16 is sucked into the compressor 11 through the low-pressure side pipe 18. The compressor 11, the high pressure side pipe 12, the condenser 13, the decompressor (expansion valve) 20, the evaporator 16, and the low pressure side pipe 18 constitute a refrigeration cycle.

FIG. 5 shows the configuration of the control circuit in the control device 30 and the refrigeration cycle.
An inverter 41 is connected to the AC power source 40, and the drive motor 11 </ b> M of the compressor 11 is connected to the output terminal of the inverter 41. The inverter 41 includes a rectifier circuit 42 that rectifies the voltage of the AC power supply 40, a smoothing capacitor 43 connected to the output terminal of the rectifier circuit 42, and a switching circuit 44 connected to the smoothing capacitor 43. The switching circuit 44 converts the DC voltage generated in the smoothing capacitor 43 into a three-phase AC voltage having a frequency and level according to a command from the control unit 50 by switching. The drive motor 11M is operated by this output.

  The control unit 50 is connected to the temperature sensor 21, the communication control unit 51, the address setting unit 52, the operation unit 53, and the display unit 54. The temperature sensor 21 detects the temperature Ta of the internal air sucked from the suction port 15a by the operation of the evaporator blower 17. The communication control means 51 controls data transmission / reception with another refrigeration apparatus through the input / output terminal 1a. The address setting means 52 is, for example, a dip switch for setting an address (for example, a number from 1 to 9) of the refrigeration apparatus, and functions as a setting means for setting the refrigeration apparatus to one of the parent device and the child device. . The operation unit 53 includes an operation switch and a temperature setting device.

And the control part 50 has the following means (1)-(5) as main functions.
(1) When the address of the master unit is set by the address setting means 52, the speed of the compressor 11 (the output of the inverter 41) is based on the difference between the detected temperature Ta of the temperature sensor 21 and the set temperature Ts of the temperature setter. (Frequency) and means for outputting operation data representing the detected temperature Ta and the set temperature Ts from the input / output terminal 1a.

  (2) When the address of the slave unit is set by the address setting means 52, the detected temperature Ta and the set temperature Ts are read from the operation data output from the input / output terminal of another master unit and input to the input / output terminal 1a. Means for controlling the speed of the compressor 11 based on the difference between the detected temperature Ta and the set temperature Ts.

  (3) Abnormalities in the refrigeration cycle equipment (compressor 11, condenser 13, decompressor 20, evaporator 16, condenser blower 14, evaporator blower 17, etc.) are detected by a refrigerant pressure sensor and a refrigerant temperature sensor (not shown). Means to detect.

  (4) When the above abnormality is detected, if the device itself is a parent device, an abnormality signal is output from the input / output terminal 1a. Means for outputting from terminal 1a to another slave unit.

  (5) Means for executing the same control as when set as the master unit when an abnormal signal output from the master unit is input to the input terminal 1a when the slave unit itself is a slave unit.

  The configuration of the other control devices 2, 3, and 4 is the same. Therefore, the description is omitted.

Next, the operation of the above configuration will be described with reference to the flowchart of FIG.
When the address (number) of the refrigeration apparatus is set by operating the address setting means 52, the address is read (step 101), and the read address is transmitted to another refrigeration apparatus (step 102). ). In addition, an address transmitted from another refrigeration apparatus is received / confirmed / stored (step 103). When this address is received, it is determined whether or not an abnormal signal is included (step 104). If an abnormal signal is included (YES in step 104), the address of the refrigeration apparatus having the abnormality is stored (step 105).

  When an abnormal signal is not included (NO in step 104), or after storing the address of the refrigeration apparatus having an abnormality, the address to be read, the address received from another refrigeration apparatus, the address of the refrigeration apparatus having an abnormality Based on the mutual comparison, it is determined whether or not its own address is the smallest in a normal refrigeration apparatus (step 106).

  If the address is minimum (YES in step 106), it is determined whether or not there is an abnormality on the basis of the determination that the refrigeration apparatus is a master unit (step 107). If the address is not the minimum (NO in step 106), the process proceeds to step 116 under the determination that the refrigeration apparatus is a slave unit.

  If the refrigeration apparatus is a master unit and there is no abnormality in itself (NO in step 107), it is determined whether or not a command issued from the operation unit 53 is on (step 108).

  If an operation on command has been issued (YES in step 108), the detected temperature Ta of the temperature sensor 21 and the set temperature Ts of the temperature setting device in the operation unit 53 are read (step 109), and the detected temperature Ta is set. The output frequency of the inverter 41 is determined based on the difference from the temperature Ts (step 110). The compressor 11 is driven at a speed corresponding to the output frequency, and a cooling operation having a capacity corresponding to the speed is executed (step 111). For the determination of the output frequency, various known methods such as PID control and fuzzy control based on the combination of the difference between the room temperature and the set temperature and the time change of the difference can be applied.

  When a command to turn off the operation is issued (NO in step 108), processing for stopping the operation of the refrigeration apparatus is executed (step 112).

  Then, operation data representing the on / off state of operation, the detected temperature Ta, and the set temperature Ts is transmitted from the master unit to another refrigeration apparatus (step 113).

  If there is an abnormality in the parent device (YES in step 107), the operation of the parent device is stopped abnormally, the fact of the abnormal stop is displayed on the display unit 54 (step 114), and the abnormality signal is sent to its own address. At the same time, it is transmitted to another refrigeration apparatus (child unit) (step 115).

  On the other hand, if the refrigeration apparatus is a slave unit (NO in step 106), operation data transmitted from another master unit is received, and the master unit on / off state, detected temperature Ta, set temperature is received from the operation data. Ts is read (step 116). By reading the on / off state, it can be determined whether the operation of the master unit is on or off.

  If the master unit is on (YES at step 117), the output frequency of inverter 41 is determined based on the read detected temperature Ta and set temperature Ts (step 118). The compressor 11 is driven at a speed corresponding to the output frequency, and a cooling operation having a capacity corresponding to the speed is executed (step 120). If the master unit is turned off (NO in step 117), a process for stopping the operation of the refrigeration apparatus is executed (step 119).

  If there is an abnormality in the slave unit (YES in step 121), the operation of the slave unit is stopped abnormally, the fact of the abnormal stop is displayed on the display unit 54 (step 114), and the abnormal signal is the address of itself. At the same time, it is transmitted to other refrigeration apparatuses (master unit and other slave units) (step 115).

  In short, among the refrigeration apparatuses, the refrigeration apparatus having the smallest address is automatically set as the master unit. Then, in the parent device, the cooling operation with the capacity determined based on the detected temperature Ta and the set temperature Ts of the parent device is executed. In the slave unit, a cooling operation having a capacity corresponding to the air conditioning load of the master unit is executed.

  In this way, all the refrigeration apparatuses 1, 2, 3, and 4 set as the master unit and the slave units individually execute the operation according to the air conditioning load of the master unit, thereby refrigeration apparatuses 1, 2, and 3 , 4 can be uniformly cooled by the refrigeration apparatuses 1, 2, 3, 4 without interfering with each other in the cooling operation of the storage basin R.

  In addition, since all the refrigeration apparatuses 1, 2, 3, and 4 set as the master unit and the slave unit are configured to individually execute the operation with the capability according to the detected temperature Ta and the set temperature Ts of the master unit. Protective operations such as so-called compressor current release, compressor discharge temperature release, discharge pressure release, etc. have priority over this capacity control and have the advantage that each of the refrigeration apparatuses 1, 2, 3, 4 can be executed independently. .

  When an abnormality occurs in the parent device, the operation of the parent device is stopped, and among the child devices that are operating normally, a child device having the smallest address is newly set as the parent device. Then, the new master unit performs a cooling operation with a capacity corresponding to the air conditioning load of the own machine, and the other slave units perform a cooling operation with a capacity corresponding to the detected temperature Ta and the set temperature Ts of the new master unit. The In other words, regardless of the abnormal stop of the master unit, appropriate cooling by the linked operation of the new master unit and the slave unit is continued.

  If an abnormality occurs in any of the slave units, the operation data from the master unit is distributed to all the remaining slave units simply by stopping the operation of the slave unit. Therefore, also in this case, appropriate cooling by the linked operation of the master unit and the remaining slave units is continued.

  In addition, when the refrigeration apparatuses 1 to 4 are installed alone, the data signal line 6 is not connected, so that signals from other machines are not input, and the address of the own machine is always the minimum address. In step 106 in the flowchart of FIG. Since the operation of the parent machine operates based on the detected temperature Ta and the set temperature Ts of the own machine, it can be operated without any change from the operation of a normal single-installed device. For this reason, this refrigeration apparatus can be used for both a plurality of installations and a single installation, and is versatile.

  In addition, this invention is not limited to the said embodiment, A various deformation | transformation implementation is possible in the range which does not change a summary.

The external appearance perspective view of each freezing apparatus of one Embodiment. The figure which shows the input / output terminal of each refrigeration apparatus in one Embodiment, and the connection state between them. The figure which looked at the external appearance and internal structure of each freezing apparatus of one Embodiment from the upper direction. The figure which looked at the external appearance and internal structure of each freezing apparatus of one Embodiment from the side. The figure which shows the structure of the control circuit in the control apparatus of one Embodiment, and a refrigerating cycle. The flowchart for demonstrating the effect | action of one Embodiment.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 1, 2, 3, 4 ... Refrigeration apparatus, 5 ... Signal cable, 6 ... Data signal line, 7 ... Ground wire, 10 ... Three-phase alternating current power supply, 11 ... Compressor, 13 ... Condenser, 14 ... Blower for condensers, DESCRIPTION OF SYMBOLS 15 ... Evaporator unit, 15a ... Suction inlet, 15b ... Outlet, 16 ... Evaporator, 17 ... Blower for evaporator, 18 ... Duct, 41 ... Inverter, 50 ... Control part, 52 ... Address setting means

Claims (3)

In a refrigeration apparatus comprising a compressor, a condenser, a decompressor, an evaporator, a blower and other refrigeration cycle equipment, a temperature sensor, a temperature setter, and a control device for controlling the refrigeration cycle equipment, which are driven at a variable speed by an inverter,
The control device includes setting means for setting the refrigeration device to either the parent device or the child device, and an input / output terminal,
When set to the master unit, the speed of the compressor is controlled based on the difference between the temperature detected by the temperature sensor and the temperature set by the temperature setter, and operation data representing the detected temperature and the set temperature is input to the master unit. Output from the output terminal,
When set to the slave unit, the detected temperature and the set temperature are read from the operation data output from the master unit and input to the input / output terminal, and the speed of the compressor is determined based on the difference between the detected temperature and the set temperature. Control,
A refrigeration apparatus characterized by that. The controller is
When an abnormality occurs in the refrigeration cycle equipment,
If the device itself is a master unit, an abnormal signal is output from the input / output terminal,
If it is a slave unit, the operation data input to the input / output terminal is output from the input / output terminal to another slave unit.
2. The refrigeration apparatus according to claim 1, wherein In the case where the control device itself is a slave device, when an abnormal signal output from the master device is input to the input / output terminal, the control device performs the same control as that set when the master device is set. The refrigeration apparatus according to claim 2.

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