JP2001272148A - Control device for refrigerator - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a control device for a refrigerator in which a temperature control of high precision can be realized while a frequent ON-OFF operation of the refrigerator is being avoided. SOLUTION: A refrigerator is controlled in its ON-OFF operation between an upper limit temperature and a lower limit temperature so as to control a temperature of a storing chamber 39. A time of one cycle ranging from an ON state of the refrigerator to a next ON state or from an OFF state of the refrigerator to a next OFF state is measured and a difference between the upper limit temperature and the lower limit temperature is changed in response to this measured time.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION The present invention relates to a cooling device that is turned on and off between an upper limit temperature and a lower limit temperature.
The present invention relates to a control device for a cooling storage that controls the temperature of a storage room.

[0002]

2. Description of the Related Art Conventionally, stores such as supermarkets and convenience stores are provided with a plurality of open showcases and refrigerators (all of which are cooling storages). Each of the open showcases and refrigerators has an upper limit temperature and a lower limit temperature set above and below the set temperature (or an upper limit temperature set above the set temperature as the lower limit temperature and the lower limit temperature or the set temperature. Between the upper limit temperature and the lower limit temperature set below the upper limit temperature, the compressor of the cooling device is turned ON / OFF, or the liquid solenoid valve is opened (O
N)-Closed (OFF). In addition, in any case, ON-OF of the cooling device
By regarding the storage chamber as F (the same applies hereinafter), the storage chambers were each kept at a set temperature (refrigeration, ice temperature, freezing, etc.).

[0003]

By the way, in this kind of cooling storage, the temperature decreases after the cooling device is turned on, and the time from when the cooling device reaches the lower limit temperature to when the cooling device is turned off or when the temperature is increased after the cooling device is turned off. Goes on, reaches upper limit temperature and turns on again
The time required for this depends on the load in the storage room and the ambient temperature. For this reason, depending on the situation, the cooling device is not turned on for a long time, and conversely, it is not turned off, and one cycle of ON-ON and OFF-OFF becomes longer. In such a situation, the temperature in the storage room becomes extremely unstable.

If the differential width, which is the difference between the upper limit temperature and the lower limit temperature, is narrowed to solve this problem, the load is increased this time, and when the ambient temperature is high, it is immediately turned on.
When the load is small and the ambient temperature is low, the cooling device is frequently turned on and off, for example, it is turned off immediately when the ambient temperature is low, and the durability of the compressor and the liquid solenoid valve is reduced. Will occur.

[0005] The present invention has been made to solve the above-mentioned conventional technical problem, and frequently requires the cooling device to be turned on and off frequently.
An object of the present invention is to provide a control device for a cooling storage, which can realize high-precision temperature control while avoiding turning off.

[0006]

That is, the control device of the cooling storage according to the present invention controls the temperature of the storage room by ON-OFF controlling the cooling device between the upper limit temperature and the lower limit temperature. Measuring the time of one cycle from the ON of the cooling device to the next ON or from the OFF to the next OFF, and changing the difference between the upper limit temperature and the lower limit temperature according to the measured time. .

The control device for a cooling storage according to the second aspect of the present invention compares the reference one cycle time with the measurement time, and if the measurement time is longer than the reference one cycle time, the upper limit is set. Reduce the difference between the temperature and the lower limit temperature,
When it is shorter, the difference between the upper limit temperature and the lower limit temperature is enlarged.

According to the present invention, in the control device of the cooling storage for controlling the temperature of the storage room by controlling the ON / OFF of the cooling device between the upper limit temperature and the lower limit temperature, from the ON of the cooling device to the next ON. Alternatively, one cycle time from OFF to the next OFF is measured, and the difference between the upper limit temperature and the lower limit temperature is changed according to the measured time. One cycle time and measurement time are compared. If the measurement time is longer than the reference one cycle time, the difference between the upper limit temperature and the lower limit temperature is reduced. The time of one cycle of ON-ON or OFF-OFF of the cooling device, which tends to fluctuate according to the load in the storage room and the ambient temperature condition, is set to It is possible to fall within a range defined by.

This makes it possible to prevent the inconvenience that the cooling device is frequently turned on and off while suppressing the temperature fluctuation in the storage room, thereby realizing highly accurate temperature control in the storage room. In addition, it is possible to extend the life of the cooling device.

[0010]

Embodiments of the present invention will be described below in detail with reference to the drawings. FIG. 1 is a longitudinal side view of an open showcase 1 as an embodiment of a cooling storage to which the present invention is applied,
FIG. 2 is a diagram illustrating a piping configuration in a store such as a supermarket where the open showcase 1 is installed,
FIG. 3 is a system configuration diagram of the centralized control device such as the open showcase 1.

The open showcase 1 of the embodiment is a so-called vertical open low-temperature showcase, and has a heat insulating wall 32 having a substantially U-shaped cross section and side plates (not shown) attached to both sides of the heat insulating wall 32 at the installation site. ) Constitute the showcase body 20. An outer partition plate 34 and an inner partition plate 36 are provided inside the heat insulating wall 32 at intervals.
An outer duct 37 is provided between the heat insulating wall 32 and the outer partition plate 34, an inner duct 38 is provided between the inner and outer partition plates 36, 34, and a storage chamber 39 is provided inside the inner partition plate 36.

In the storage room 39, a plurality of shelves 41 are provided.
Are mounted, and fluorescent lamps 40 are mounted as illumination lights in the front lower surface of each shelf 41, the ceiling of the storage room 39, and the eave 35. A deck pan 42 is attached to the bottom of the storage room 39.
The lower part is a bottom duct 43 communicating with the ducts 37 and 38. A fan case 44 having a blower 45 built therein is installed in the bottom duct 43.
Further, an evaporator 46 included in the cooling device is provided vertically below the inner layer duct 38 located behind the storage room 39. A storage room 39 is provided on the front surface of the eave 35 as described later.
A display unit 55 for displaying the temperature in the inside is attached, but this may be a standard or an optional attachment.

At the upper edge of the front opening 51 of the storage chamber 39, an outer layer discharge port 52 and an inner layer discharge port 53 are juxtaposed in front and rear. The outer layer discharge port 52 is connected to the outer layer duct 37 by the inner layer discharge port 53.
Are respectively connected to the inner layer ducts 38. A suction port 54 is formed at a lower edge of the opening 51 and communicates with the bottom duct 43.

When the blower 45 in the fan case 44 is operated, the air in the bottom duct 43 is blown toward the inner and outer ducts 37 and 38 at the rear, and is blown up as it is in the outer duct 37. In the inner layer duct 38, the heat is exchanged with the evaporator 46 and then blown up, and then blown out from the inner and outer layer discharge ports 52 and 53 at the upper edge of the opening 51 toward the suction port 54 at the lower edge.

As a result, an inner cold air curtain and an outer air curtain for protecting the same are formed in the opening 51 of the storage chamber 39, and the invasion of outside air from the opening 51 is prevented or suppressed. A part of the inner cold air curtain circulates in the storage room 39 and the inside of the storage room 39 is cooled. Then, the cool air is supplied to the suction port 54.
From the bottom duct 43 and is sucked into the blower 45 again.

Next, in FIG. 2, 1a... Indicates an open showcase (refrigerated case for fruits and vegetables) for storing and displaying fruits and vegetables (products), and 1b. It is an open showcase (ice temperature case for fresh fish) to be stored and displayed. Each open showcase 1a
1b are installed along the wall surface of the store in the supermarket as shown in FIG. On the other hand, 11, 12
Are a separate-type refrigeration refrigerator (condensing unit) and an ice-temperature refrigerator (condensing unit) which are installed (separately installed) in a machine room 13 formed outside the store. Constitute.

Each of the refrigerators 11 and 12 is composed of a compressor and a condenser (not shown), and the inlet side of the evaporator 46 of the open showcase 1a (refrigerated case) is a liquid solenoid valve 14 and a liquid electromagnetic valve 14, respectively. The refrigerant is connected in parallel with the liquid refrigerant pipe 17 of the refrigerator 11 via the expansion valve 16, and the outlet side of the evaporator 46 is connected in parallel with the gas refrigerant pipe 18 of the refrigerator 11.

The inlet side of the evaporator 46... Of the open showcase 1 b (ice temperature case) is a liquid refrigerant pipe of the ice temperature refrigerator 12 via a liquid solenoid valve 19 and an expansion valve 21, respectively. 22 and the outlet side of the evaporator 46 is connected to the gas refrigerant pipe 23 of the ice temperature refrigerator 12.
Are connected in parallel.

Next, referring to FIG. 3, a system of the centralized control device of the open showcase 1 (1a, 1b) includes a main control device 61 provided in a security room of a store and the like, and each open showcase 1 (1a, 1b). ) And refrigerators 11 and 12
And a chip-shaped terminal device 62 serving as a temperature sensor and a switching element. In this case, a series of signal lines 63 are provided in the main body 20 including the inside of the raceway 25 provided below the front wall of the heat insulating wall 32 of each open showcase 1 (1a, 1b). The inside of the raceway 25 is a crossover wiring 63A extending between both ends of the main body 20, and connectors 64, 64 are provided at both ends of the crossover wiring 63A at both ends of the main body 20.

The terminal device 62 is connected to a signal line 63 in the main body 20 by a connector. Also, the crossover wiring 63A of each of the open showcases 1a.
Are connected to each other using the connectors 64 at both ends, and further connected to the terminal device 62 of the refrigerator 11 via the signal line 63 and the connector 64 to form a first system.
Are connected to each other using the connectors 64 at both ends, and the signal lines 63 and the connectors 64 are also connected to the terminal device 62 of the refrigerator 12. To form a second system.

The main controller 61 is connected to a similar signal line 63.
Are connected to the connectors 64 of the crossover wiring 63A of the open showcases 1a and 1b, which are the parent of each system, so that all the terminal devices 62 are connected to the main control device 61 via the signal lines 63. And are also connected to each other.

Thus, each open showcase 1
The crossover wiring 63A of the signal line 63 is disposed on the raceway 25 of (1a, 1b), and the connectors 64, 64 connected to both ends of the crossover wiring 63A are disposed at both ends of the main body 20. Therefore, after the open showcases 1 are juxtaposed, the open showcases 1a, 1b,.
The operation of connecting the signal lines 63 is extremely easy.

In FIG. 3, open showcase 1 (1
FIGS. 1a and 1b) show one terminal device 62 for each of the liquid solenoid valves 14 and 19 and the blower 45, and the terminal device 62 shown in FIG. Terminal device 62 functioning as a temperature sensor as shown
Is provided.

Next, the configuration of the main control unit 61 is shown in FIG. A controller (substrate) 76 is provided in the main control device 61 as a main control means. The controller 76 includes a CPU (microcomputer) 71, an EEP
A memory 72 as a storage unit composed of a ROM or a flash memory, an I / O interface 73, and a bus I / O interface 74 as a transmission / reception unit
It is composed of In addition, the main controller 61 includes, for example, a display 7 composed of an LCD display panel.
7 and a switch 78 as input means.

The bus I / O interface 7
4 exchanges data with the terminal devices 62... Via the switch 79 and the signal line 63. Also, this switch 7
Reference numeral 9 is connected to a terminal adapter 80 via a communication line 82, and can communicate with an external maintenance company or the like using an ISDN line.

The memory 72 of the controller 76 has a predetermined communication protocol for performing data communication with the terminal device 62 or a personal computer of an external maintenance company, software for identifying the terminal device 62, and operation control. A control program for performing is set. Further, each open showcase 1 (1
Set value data such as the set temperatures a and 1b) and the threshold value of the alarm temperature can be set, and these data are written to the memory 72.

In the memory 72 of the controller 76, the set temperature T of the storage room 39 set by the switch 78 for each open showcase 1 (1a, 1b) is stored.
A data table of a control upper limit temperature TH (standard value) and a lower limit temperature TL (standard value) corresponding to S is written.

That is, the storage room 3 of the open showcase 1
9 is open at the front opening 51 as shown in FIG. 1, so that no matter how the cold air curtain and the protective air curtain are formed, they are easily affected by external heat.
The temperature tends to be unstable. Therefore, conventionally, the storage room 39
Without controlling the cooling device at the temperature of the cooling device (the liquid solenoid valves 14, 19) based on a temperature sensor that detects the temperature of the cool air discharged from the inner layer discharge port 53 via the innermost layer duct 38, which is the most stable. Opening and closing).

In this case, the temperature of the cool air discharged from the inner layer discharge port 53 must be lower than the temperature in the storage room 39, so that the temperature detected by the temperature sensor is directly displayed as the temperature of the storage room 39. I can't. Therefore, in the related art, the temperature inside the storage room 39 is displayed by attaching a thermometer for detecting the temperature inside the storage room 39 to the position of the display unit 55 or the like.

Therefore, in the case of the present application, the control upper limit temperature TH corresponding to the set temperature TS of the storage chamber 39 as described above.
And a data table of the lower limit temperature TL is written in the memory 72 of the controller 76 in advance. The upper limit temperature TH and the lower limit temperature TL are based on the temperature in the storage room 39 detected by the terminal device 62 provided on the ceiling in the storage room 39, and the cooling device (liquid) is used at the upper limit temperature TH and the lower limit temperature TL. When the solenoid valves 14, 19, etc.) are controlled to be open (ON) -closed (OFF), the temperature in the storage chamber 39 is a value that has been previously confirmed by experiments as a value that is maintained at the set temperature TS corresponding to them. , Is determined corresponding to each set temperature TS. Further, a data table in which each set temperature TS corresponds to the upper limit temperature TH and the lower limit temperature TL is predetermined for each open showcase 1 (1a, 1b).
It is written in the memory 72.

Thus, the temperature control of the open showcase 1 as described later can be achieved by controlling the cooling device based on the temperature in the storage room 39.
Also, when displaying the temperature in the storage room 39, there is no need to provide a separate thermometer.

Next, the configuration of the terminal device 62 is shown in FIG. The terminal device 62 includes a CPU serving as a terminal-side control unit.
143 (which may be constituted by logic), a memory 144 as storage means, and an I / O as transmission / reception means.
An O interface 146, an A / D converter 147,
The sensor unit 148 as a temperature detecting element connected to the A / D converter 147 and the capacitor 1 as a power storage element
49, a diode 151 as a rectifying element, an I / O interface 162 as a driver,
It comprises a transistor 163 and the like as switching means connected to the O interface 162.

In this case, the capacitor 149 is connected to the output side of the diode 151, and each element is connected to a connection point between the diode 151 and the capacitor 149.
A potential (high potential) of, for example, +5 V is applied to the signal line 63, and data is configured by a pulse that falls from the high potential to a low potential of 0 V, for example.

When the terminal device 62 is connected to the signal line 63, power is supplied to each element as it is while the high-potential and low-potential pulse signals constituting data are at the high potential. Is also charged. Then, while the potential is low, the capacitor 149 discharges power to supply power to each element.

The terminal device 62 has Vcc (DC + 5).
V) A power supply terminal 145 is also provided, which is connected to a connection point between the diode 151 and the capacitor 149. If the Vcc power supply terminal 145 is connected to a power supply line, each element is supplied with power from the power supply line. It is configured so that it can also operate. That is, in this case, since each element operates without filling the capacitor 149, the convenience is improved when the terminal device 62 is required to be operated promptly at the time of inspection or the like.

When the CPU 143 functions as a temperature sensor, the inside of the storage room 39 of the open showcase 1 detected by the sensor unit 148 (hereinafter, referred to as the inside temperature TP).
Is fetched via the A / D converter 147, and is temporarily written into the memory 144. Then, the controller 7 is connected via the signal line 63 by the I / O interface 146.
When polling is performed by the controller 6, the temperature data (internal temperature TP) written in the memory 144 is transmitted to the controller 76 via the signal line 63 by the I / O interface 146.

Here, the memory 144 has an ID code of the terminal device 62 itself, an object to be controlled (the liquid solenoid valves 14 and 19 or the blower 45, the compressors of the refrigerators 11 and 12, and the like), and an open showcase provided with itself. 1 (1a, 1b), information as to whether or not it functions as a temperature sensor, set value data such as the set temperature TS and the threshold value of the alarm temperature (these are distributed from the controller 76), and the controller 76 And a communication protocol for performing data communication with the terminal device 62 and a control program for performing operation control. Also,
If a failure has occurred in the terminal device 62, the failure data is also written to the memory 144, and the controller 7
6 is sent. Further, the ID code of the terminal device 62 of the open showcase 1 (1a, 1b) of the system to which the terminal belongs and the identification data are also written into the memory 144.

The CPU 143 is connected to the controller 7 via the signal line 63 by the I / O interface 146.
6 transmits ON / OFF data, the ON / OFF data
I / O interface 162 based on OFF data
To turn on / off the transistor 163. Note that the terminal device 62 has a self-holding function for holding the current state when communication with the controller 76 is interrupted.

Here, the terminal device 62 is wired on a board (not shown) as shown in FIG.
68. That is, 169 is the photodiode 16
Reference numeral 171 denotes a resistor, 172 denotes a diode as a rectifying element, and 174 denotes a capacitor as a power storage element.

In this case, the capacitor 174 is connected to the output side of the diode 172, and a resistor 171 is connected between the connection point of the diode 172 and the capacitor 174 and the collector terminal (indicated by S2 in FIG. 5) of the transistor 163 of the terminal device 62. And the photodiode 169A are connected in series. The terminal S1 (FIG. 5) of the terminal device 62 is connected before the diode 172. The phototriac 169B is interposed between the AC power line and the liquid solenoid valves 14, 19, the blower 45, or the compressors of the refrigerators 11, 12.

When the diode 172 is connected to the signal line 63, power is supplied to the photodiode 169A via the resistor 171 as long as the high-potential and low-potential pulse signals constituting data are at the high potential. , Condenser 1
74 is also charged. While the potential is low, the capacitor 174 discharges the photodiode 1
The power supply of 69A is provided.

Similarly, if the Vcc power supply terminal 160 is connected to the connection point between the diode 172 and the capacitor 174, and this Vcc power supply terminal 160 is connected to the power supply line, the photodiode 169A operates even when power is supplied from the power supply line. Will be able to do it. That is, in this case, each element operates without filling the capacitor 174, so that the convenience is improved when it is desired to quickly operate at the time of inspection or the like.

The operation of the above configuration will now be described.
Note that the central control mode and the independent control mode can be selectively set in the main control device 61 and the terminal device 62, and among them, the energy saving mode and the high freshness mode can be selectively set, respectively. Hereinafter, the energy saving mode of the centralized control mode will be described first.

Now, it is assumed that the switch 79 connects the line between the bus I / O interface 74 of the controller 76 and the signal line 63. Open showcase 1 (1
a, 1b) are installed in the store, and the open showcases 1a, 1b of each system and the signal lines 63 of the refrigerators 11, 12 are provided.
Are connected, the CPU 71 of the controller 76 of the main control device 61 first scans the connection status of each terminal device 62 to the signal line 63, and
.. Are collected.

The CPU 71 of the controller 76 identifies the connection status of the terminal devices 62,... Based on the collected ID code, and stores the status in the memory 72. Thereafter, the CPU 71 communicates with each terminal device 62,. To send and receive data. In addition, the ID code of the terminal device 62 of the open showcase 1a, 1b of each system is distributed to the terminal device 62 of the open showcase 1a, 1b of each system. When the CPU 143 of the terminal device 62 receives this via the I / O interface 146, the
Write to 4.

Next, the CPU 71 of the controller 76 polls the terminal devices 62... Mounted on the ceiling of the storage room 39 functioning as temperature sensors in each of the open showcases 1 (1a, 1b). At this time, the controller 76 transmits a communication command and the terminal device 6
2 returns an OK command. Controller 76
Transmits the call command of the terminal device 62 and the ID code of the terminal device 62.

Then, a temperature measurement start command is transmitted. The CPU 143 of the terminal device 62 measures the temperature data as described above in response to the polling, and stores it in the memory 144. Next, the controller 76 transmits a communication start command again, and an OK command is returned from the terminal device 62. The controller 76 transmits the call command of the terminal device 62 and the ID code of the terminal device 62.

Then, a memory call command is transmitted. In response to the polling, the CPU 143 of the terminal device 62 returns the temperature data stored in the memory 144 as described above. Finally, the controller 76 transmits a reset command, and the terminal device 62 returns an OK command.

The CPU 71 of the controller 76 once writes the collected temperature data in the memory 72, and stores the temperature data, that is, the internal temperature TP and the set temperature T.
The control unit compares the upper limit temperature TH and the lower limit temperature TS corresponding to S and transmits ON / OFF data together with the ID code to each of the terminal devices 62 via the signal line 63.

For example, the terminal device 62 of the liquid solenoid valves 14 and 19
Receives the ON / OFF data of its own ID code, the CPU 143 turns ON / OFF the transistor 163 based on the received data. This transistor 163
Is turned ON / OFF, the photodiode 169A becomes O
N (emission) / OFF (extinguish), whereby the phototriac 169B is turned ON / OFF, whereby the liquid solenoid valves 14, 19 are opened and closed.

The terminal device 62 of each of the refrigerators 11 and 12
ON / OFF data is transmitted in the same manner, but in this case, all open showcases 1a, 1a, 1b,
When the liquid solenoid valves 14 and 19 of b are closed, OFF data is transmitted, and when either of them is open, ON data is transmitted. Note that the blower 45 is normally operated continuously.

The controller 76 sends the received temperature data, that is, each open showcase 1 (1a, 1a, 1a).
The internal temperature TP of b) is displayed on the display 77. A display having the same function as the display 77 may be provided in the display unit 55. As a result, the temperature can be displayed using the temperature data from the terminal device 62 in the storage room 39 for detecting the temperature data for control without providing a special thermometer.

The liquid solenoid valves 14, 19, the refrigerator 11,
The CPU 143 of the twelve terminal devices 62 stores the open showcase 1 or the refrigerators 11 and 1 in the memory 144.
2, the open / close state of the liquid solenoid valves 14, 19 or the refrigerator 11,
Twelve operation states and data on the respective operation rates are written. The CPU 143 of the terminal device 62 determines whether the liquid solenoid valves 14 and 19 are open (ON) and then open (ON) or next closed (OFF) and then closed (OF).
The time of one cycle up to F) is measured, and the data on the operating rate includes the measured time of this one cycle. It should be noted that the supply of the refrigerant is not controlled by the liquid solenoid valves 14 and 19 but the compressors of the refrigerators 11 and 12 are directly turned on and off. Until the next ON or O
This is the time from the FF to the next OFF.

The data is transmitted to the controller 76 in response to a request from the controller 76. If a failure has occurred in the terminal devices 62..., The failure data is transmitted from the CPU 143 of each terminal device 62 to the controller 76. CPU 71 of controller 76
When such failure data is received, the display 77 displays that the terminal device 62 has a failure. As a result, the controller 76 can collectively manage the operations and operating states of the open showcases 1 and the refrigerators 11 and 12.

Here, the high freshness mode will be described. When the high freshness mode is selected, the controller 76
Based on the reference one cycle time such as 5 minutes or 10 minutes as the measurement time of one cycle, one cycle sent from the terminal device 62 such as the liquid solenoid valves 14 and 19 from the reference one cycle time as described above. If the measurement time is long, for example, the standard upper limit temperature TH is lowered and the standard lower limit temperature TL is raised, so that the upper limit temperature TH is increased.
And the differential width, which is the difference between the temperature and the lower limit temperature TL, is reduced.

Conversely, when the measurement time of one cycle sent from the terminal device 62 is shorter than the reference one cycle time, for example, the standard upper limit temperature TH is increased and the standard lower limit temperature TL is decreased. The differential width, which is the difference between the upper limit temperature TH and the lower limit temperature TL, is increased. This change width is, for example, 0.25 deg (resolution 0.0612)
5 deg) with an accuracy (step).

Thus, the cooling device (the liquid solenoid valves 14, 1)
9) can be converged within one reference cycle time while eliminating frequent ON-OFF operations, and high-precision temperature control that suppresses temperature fluctuations in the storage chamber 39 can be performed. Achieved.

Next, the independent control mode will be described. In this case, the open showcase 1a of each system,
As described above, the terminal device 62 of the other open showcases 1a and 1b belonging to the terminal device 62 of the
Information such as the ID code is distributed.

The set temperature TS is stored in the memory 144 of the terminal device 62 of the open showcases 1a and 1b which are the parent of each system (if there are a plurality of them, one of them is representative).
The set value data such as the upper limit temperature TH and the lower limit temperature TL and the threshold value of the alarm temperature are written using the main controller 61. The parent open showcases 1a and 1b compare the temperature data detected by the sensor unit 148 with the set temperature and turn ON / OFF data on the terminal devices of all open showcases 1a and 1b and the refrigerators 11 and 12 belonging to the system. 62.

As a result, the liquid solenoid valves and compressors of the open showcase 1a and the refrigerator 11 or the open showcase 1b and the refrigerator 12 of each system are turned on in synchronization.
(Open or run) / OFF (close or stop). In particular, the operation time of the compressor can be reduced as compared with the conventional pump-down system, and energy can be saved. Further, in the open showcase 1 other than the parent, the terminal device 62 functioning as the temperature sensor can be deleted, and the main control device 61 can also be deleted, so that the cost of parts can be reduced.

As described above, the CPU 143 of the liquid solenoid valves 14 and 19 and the terminal device 62 of the refrigerators 11 and 12 stores the open showcase 1 or the liquid solenoid valves 14 and 19 of the refrigerators 11 and 12 in the memory 144. The data about the open / closed state or the operation state of the refrigerators 11 and 12 and the respective operation rates are written. In this mode, the data becomes the parent in response to a request from the parent open showcases 1a and 1b. Open showcase 1a, 1b
To the terminal device 62. As a result, in the parent open showcases 1a and 1b, the respective open showcases 1a and 1b and the refrigerators 11 and 12 belonging to the system to which the parent belongs.
Operation and operation state can be managed collectively.

When a failure has occurred in the terminal device 62, the failure data is stored in the CPU 14 of each terminal device 62.
3 is transmitted to the terminal device 62 of the open showcases 1a and 1b serving as parents. When the CPU 143 of the parent open showcases 1a and 1b receives the failure data, it writes the failure data into the memory 144. In this mode, when there is the main control device 61, the main control device 61 reads out and manages these data from the parent open showcases 1a and 1b by another personal computer or the like when there is no main control device. .

In this independent control mode, the power saving mode and the high freshness mode as described above are executed by the parent terminal device 62. Further, in the embodiment, the high freshness mode is executed by comparing the reference one cycle time with the measurement time. However, the present invention is not limited to this, and the measurement time of the previous one cycle is compared with the measurement time of the present one cycle, and the current time is longer. The differential width may be reduced when it becomes smaller, and expanded when it becomes shorter. According to such a configuration, it is also possible to perform automatic tuning to an optimum and narrowest differential width.

In the independent control mode, independent control is executed for each system. However, the present invention is not limited to this, and independent control may be executed by the terminal device 62 in each open showcase 1. In this case, the terminal device 62 of the parent open showcase 1a, 1b sends the set temperature TS (upper limit temperature TH, lower limit temperature T) to the terminal device 62 of another open showcase 1a, 1b to which the parent belongs.
L and the threshold value of the alarm temperature.

Then, the other open showcase 1 executes the temperature control of the open showcase 1 using the distributed data and the temperature data detected by its own sensor unit 148. Further, in the embodiment, an open showcase is taken as a cooling storage, but the present invention is not limited to this, and the present invention is also effective for a refrigerator or a prefabricated refrigerator.

[0066]

As described above in detail, according to the present invention, a cooling storage control device for controlling the temperature of a storage room by controlling the cooling device ON-OFF between an upper limit temperature and a lower limit temperature. Since the time of one cycle from the ON of the device to the next ON or from the OFF to the next OFF is measured, and the difference between the upper limit temperature and the lower limit temperature is changed according to the measured time, for example, As in 2, the reference time of one cycle is compared with the measurement time. If the measurement time is longer than the reference time of one cycle, the difference between the upper limit temperature and the lower limit temperature is reduced. If the difference between the upper limit temperature and the lower limit temperature is enlarged, the time of one ON-ON or OFF-OFF cycle of the cooling device, which tends to fluctuate depending on the load in the storage room and the ambient temperature condition, is set as a reference. 1 can be kept within the range defined by the cycle time that.

Thus, it is possible to prevent the inconvenience that the cooling device is frequently turned on and off while suppressing the temperature fluctuation in the storage room, thereby realizing highly accurate temperature control in the storage room. In addition, it is possible to extend the life of the cooling device.

[Brief description of the drawings]

FIG. 1 is a vertical side view of an open showcase as an embodiment to which the present invention is applied.

FIG. 2 is a diagram illustrating a piping configuration in a store such as a supermarket where the open showcase of FIG. 1 is installed.

FIG. 3 is a system configuration diagram of a centralized control device such as an open showcase to which the present invention is applied.

FIG. 4 is a block diagram of an electric circuit of a main control device.

FIG. 5 is a block diagram of an electric circuit of the terminal device.

FIG. 6 is a block diagram of an electric circuit of the switching unit.

[Explanation of symbols]

 1, 1a, 1b Open showcase 11, 12 Refrigerator 14, 19 Liquid solenoid valve 20 Main body 39 Storage room 61 Main control device 62 Terminal device 63 Signal line 64 Connector 71, 143 CPU 72, 144 Memory 74 Bus I / O interface 146 I / O interface 148 Sensor unit 163 Transistor

 ────────────────────────────────────────────────── ─── Continued on the front page (72) Inventor Kazuya Imamura 2-5-5 Keihanhondori, Moriguchi-shi, Osaka Sanyo Electric Co., Ltd. F-term (reference) 3L045 AA02 BA01 CA02 DA01 EA01 KA01 LA05 LA11 LA15 LA16 MA11 NA16 PA04

Claims (2)

[Claims] The cooling device is operated between an upper limit temperature and a lower limit temperature.
In the cooling storage that controls the temperature of the storage room by performing N-OFF control, the following ON or OFF is performed after the cooling device is turned on.
A cooling cycle control device for measuring the time of one cycle from the first to the next OFF and changing the difference between the upper limit temperature and the lower limit temperature according to the measured time. 2. The method according to claim 1, further comprising: comparing the time of one cycle as a reference with the measurement time; reducing the difference between the upper limit temperature and the lower limit temperature when the measurement time is longer than the reference one cycle time; 2. The control device according to claim 1, wherein a difference between the upper limit temperature and the lower limit temperature is increased.