JP4703299B2 - Air conditioner - Google Patents

Description

  The present invention relates to an air conditioner for air-conditioning a store such as a supermarket or a convenience store where an open type low temperature showcase is installed, and a control method for the air conditioner.

Conventionally, stores such as supermarkets and convenience stores have been installed with low-temperature showcases (open showcases) that display beverage products and refrigerated foods. The evaporator of this low temperature showcase is supplied with a refrigerant from a refrigerator separately installed outside the store, so that the internal temperature is kept low. On the other hand, an indoor unit of an air conditioner is attached to the ceiling surface of the store, and the temperature in the store is air-conditioned to a predetermined temperature.
Moreover, in this kind of air conditioner, it is based on the indoor heat load of the refrigerator for the low temperature showcase and the EPR of the refrigerator, the indoor heat load of the air conditioner, and the EPR of the air conditioner. Thus, an air conditioning set temperature of an air conditioner is calculated to reduce power demand, that is, to save energy (for example, see Patent Document 1).
JP-A-9-196432

However, in the above prior art, the defrosting operation of the low temperature showcase is not taken into consideration and the energy saving effect is insufficient.
The present invention has been made in view of the above-described circumstances, and an object thereof is to provide an air conditioner and a control method for the air conditioner that can obtain a sufficient energy saving effect when a low temperature showcase performs a defrosting operation. And

In order to achieve the above object, the present invention provides an air conditioner including an indoor unit provided in a store where an open type low temperature showcase is installed, and an outdoor unit connected to the indoor unit by a refrigerant pipe. In the apparatus, during the period of the defrosting operation of the low temperature showcase, before the temperature of the low temperature showcase chamber reaches the defrosting set temperature that is the end temperature of the defrosting operation, the chamber temperature of the low temperature showcase In the higher range, the air conditioning set temperature in the store is lowered by 1 ° C. to 2 ° C. , and after the defrosting operation is completed, the temperature in the store is restored after the temperature in the low temperature showcase returns to the set temperature in the store. It is characterized by returning to a predetermined temperature.

Further, in the present invention, in the above invention, when a plurality of the low temperature showcases are installed in the store and a plurality of the indoor units are provided, the temperature around the low temperature showcase that performs the defrosting operation is provided. Is lowered by 1 ° C. to 2 ° C. in a range higher than the internal temperature of the low temperature showcase, the air conditioning set temperature of the indoor units located around the low temperature showcase is lowered.

According to the present invention, the period of defrost operation of the low-temperature showcase, the air-conditioning set temperature in the store causes Do predetermined temperature Zadoff, the inside temperature storage room set temperature of the low-temperature showcase in operation after the end of winding the frost Since the inside temperature of the store is restored to a predetermined temperature after returning, the power consumption of the refrigerator required for returning the inside temperature of the low temperature showcase to the inside set temperature after the defrosting operation can be reduced. Therefore, the energy saving effect can be enhanced.

Hereinafter, embodiments of the present invention will be described with reference to the drawings. Hereinafter, a case where the air-conditioning apparatus according to the present embodiment is installed in a convenience store will be described.
FIG. 1 is a diagram showing an installation mode of an air conditioner 1 according to the present embodiment. As shown in this figure, the air conditioner 1 performs, for example, indoor air conditioning in a store 2 (air-conditioned room) of a convenience store, and a plurality of (2 in the illustrated example) disposed on the ceiling of the store 2 or the like. Indoor units 3A and 3B, and a heat exchanger and a compressor (not shown) which are arranged outside the store 2 and are connected to the indoor units 3A and 3B through the refrigerant piping 4 for air conditioning. And an outdoor unit 5.

  In the store 2, a refrigerated case 6 and a refrigerated case 7 are disposed as a cooling storage facility. The refrigerated case 6 includes a walk-in showcase 8 whose opening is opened and closed freely with a transparent glass door, and an open showcase 9 which is an open type low-temperature showcase whose front is open. A walk-in showcase 8 is disposed on one wall surface 2A, and a plurality (six in the illustrated example) of open showcases 9-1 to 9-6 are disposed on the other wall surface 2B. The interior of each of the walk-in showcase 8 and the open showcase 9 is cooled to a predetermined set temperature (about + 3 ° C. to + 10 ° C.), and beverage products and refrigerated foods are displayed. Unlike the walk-in showcase 8, the open showcase 9 is not provided with a door that separates the outside of the store from the inside of the store, so that cold air (air curtain) is directed downward from above the open showcase 9. It is configured to blow air.

  In addition, a freezing case 7 is disposed adjacent to the walk-in showcase 8 on one wall surface 2A of the store 2, and the inside of the freezing case 7 is cooled to a freezing temperature (−10 ° C. to −20 ° C.). And frozen desserts are on display. Outside the store 2, a cooling outdoor unit 10 having a refrigerator is juxtaposed to the air conditioning outdoor unit 5, and a refrigerated case (walk-in showcase 8, open showcase) via a cooling refrigerant pipe 11. 9) and the refrigeration case 7.

  FIG. 2 is a block diagram illustrating a functional configuration of the control device 20 of the air-conditioning apparatus according to the present embodiment. The control device 20 is installed in a management room (not shown) of the store 2, and is a general-purpose microcomputer 21 as a control means for executing control processing and various calculations, and a storage means for storing a control program and various data. The memory 22 and a communication I / F (interface) unit 23 are provided. The communication I / F unit 23 includes an air conditioning communication I / F 23A that is a communication I / F with a control device built in the air conditioning outdoor unit 5, and a control device built in the cooling outdoor unit 10. The general purpose microcomputer 21 communicates with each of the air conditioning outdoor unit 5 and the cooling outdoor unit 10 via these communication I / Fs 23A and 23B. Can be sent and received.

  The memory 22 stores a correspondence table 50 that defines the correspondence between the indoor units 3A and 3B disposed in the store 2 and the open showcases 9-1 to 9-6. More specifically, in the present embodiment, when at least one of the open showcases 9-1 to 9-6 starts the defrosting operation, the air conditioning setting of the indoor unit 3 positioned closest to the open showcase 9 is performed. The temperature is lowered by a predetermined temperature (for example, 1 ° C. to 2 ° C.) to lower the temperature around the open showcase 9 performing the defrosting operation, and as shown in FIG. The indoor units 3 positioned in the immediate vicinity of the showcases 9-1 to 9-6 are associated with each other. The correspondence relationship between the indoor unit 3 and the open showcase 9 is reset by an input from an operation unit (not shown) when the arrangement relationship is changed.

Next, the operation of the control device 20 will be described in detail with reference to FIG.
When at least one of the open showcases 9-1 to 9-6 starts the defrosting operation, a defrosting operation start notification is input from the cooling outdoor unit 10 to the general-purpose microcomputer 21 together with the identifier of the open showcase 9 Is done. When receiving the defrosting operation start notification, the general-purpose microcomputer 21 specifies the indoor unit 3 corresponding to the open showcase 9 that has started the defrosting operation based on the correspondence table 50, and sets the air conditioning of the indoor unit 3 An instruction is sent to the air conditioning outdoor unit 5 to lower the temperature D by a predetermined temperature α (for example, 1 ° C. to 2 ° C.).

  Thereby, as shown in FIG. 4, the internal temperature of the open showcase 9 starts to rise from the open showcase set temperature A from the defrosting operation start timing T <b> 1, and the open showcase is accompanied by a decrease in the air conditioning set temperature D. The room temperature around 9 will begin to fall. When the inside temperature of the open showcase 9 reaches the defrosting set temperature B and the cooling outdoor unit 10 finishes the defrosting operation timing T2 along with the defrosting operation, the cooling outdoor The unit 10 operates a built-in refrigerator to lower the internal temperature of the open showcase 9 to the set temperature A of the open showcase 9.

  Here, as described above, since the air conditioning set temperature D is lowered by the predetermined temperature α in synchronization with the defrosting operation start timing T1, before the defrosting operation end timing T2, the area around the open showcase 9 is increased. The room temperature is maintained at a temperature lowered from the air conditioning set temperature D by a predetermined temperature α. Thereby, since the thermal load around the open showcase 9 that has performed the defrosting operation is temporarily lowered, the internal temperature of the open showcase 9 is changed from the defrost set temperature B to the original open showcase set temperature A. The time required to descend will be shortened.

  When the internal temperature of the open showcase 9 returns to the open showcase set temperature A (internal temperature return timing T3), the cooling outdoor unit 10 returns the internal temperature to the open showcase set temperature A. Therefore, the operation of the refrigerator is released and the operation is shifted to the operation for maintaining the set temperature A, and the controller 20 is notified that the internal temperature has been restored. When the notification is received, the general-purpose microcomputer 21 of the control device 20 instructs the air conditioning outdoor unit 5 to return the air conditioning set temperature D to the original set temperature. As a result, the in-store temperature returns to the original air conditioning set temperature D from the timing T3 at which the inside temperature of the open showcase 9 returns to the open showcase set temperature A.

  Thus, according to the present embodiment, the in-store temperature is changed from the air conditioning set temperature D to the predetermined temperature α before the inside temperature reaches the defrost set temperature B with the defrosting operation of the open showcase 9. Since the inside temperature of the open showcase 9 is restored to the open showcase set temperature A after the defrosting operation is completed and the in-store temperature is restored to the air conditioning set temperature D after the defrosting operation is completed, Then, the heat load around the open showcase 9 is temporarily lowered, and thereby the time until the internal temperature of the open showcase 9 returns from the defrost set temperature B to the original open showcase set temperature A Will be shortened.

  Here, in general, the air conditioner has higher operating efficiency than the refrigerator for cooling the open showcase 9, so the air conditioner set temperature D of the air conditioner is lowered and the defrosting operation is completed before the open show. By temporarily lowering the thermal load around the case 9, the power consumption of the refrigerator after the defrosting operation can be suppressed, and thus the overall power consumption is reduced and the energy saving effect is enhanced. be able to.

  In addition, when the inside temperature of the open showcase 9 is restored from the defrost set temperature B to the original open showcase set temperature A, the air conditioning set temperature D is restored. Environmental changes in the store 2 can be reduced.

  In addition, according to the present embodiment, when a plurality of open showcases 9 are installed in the store 2 and the air conditioner 1 has a plurality of indoor units 3, each open showcase 9 is closest to each other. When the indoor unit 3 positioned is set in advance and the open showcase 9 starts the defrosting operation, the air conditioning set temperature D is set to a predetermined temperature only for the indoor unit 3 positioned in the immediate vicinity of the open showcase 9. Since only α is lowered, the temperature only around the open showcase 9 is lowered, the environmental change in the store 2 is minimized, and the energy saving effect can be further enhanced.

The above-described embodiment is merely an aspect of the present invention, and can be arbitrarily modified and applied within the scope of the present invention.
For example, in the above-described embodiment, when the internal temperature of the open showcase 9 returns to the open showcase set temperature A, the cooling outdoor unit 10 notifies the control device 20 of the frost. In the case where a time from the operation start timing T1 to the timing T3 when the inside temperature of the open showcase 9 returns to the open showcase set temperature A (hereinafter referred to as “inside temperature return time”) is obtained in advance. The control device 20 may operate the timer from the defrosting operation start timing T1 to count the internal temperature return time, and return the air conditioning set temperature D to the original when the timer is up.

  In the above-described embodiment, the air conditioning set temperature D is lowered at the defrosting operation start timing T1 of the open showcase 9, but the present invention is not limited to this. That is, at a timing at which the temperature around the open showcase 9 can be lowered before the internal temperature of the open showcase 9 reaches the defrosting set temperature B, that is, before reaching the defrosting operation end timing T2. Any timing can be used.

  Moreover, in embodiment mentioned above, although it was set as the structure which the control apparatus 20 receives defrosting operation start by communication from the outdoor unit 10 for cooling, it is not restricted to this but which open showcase 9 started defrosting operation. Any configuration can be used as long as the control device 20 can identify these. For example, each open showcase 9 may be provided with a temperature sensor that detects the temperature in the cabinet, and the control device 20 may detect the start of the defrosting operation of the open showcase 9 based on the detection value of each temperature sensor. good. In this case, the control device 20 may determine that the internal temperature of the open showcase 9 has returned to the open showcase set temperature A based on the detection value of the temperature sensor.

  Moreover, although embodiment mentioned above demonstrated the structure which arrange | positions the air conditioning apparatus 1 in a convenience store, even if it is a space where the open showcase 9 is arrange | positioned not only this but a school etc., for example The present invention can be applied.

It is a figure which shows the arrangement | positioning aspect to the shop of the air conditioning apparatus which concerns on embodiment of this invention. It is a block diagram which shows the functional structure of the control apparatus which concerns on this Embodiment. It is a figure which shows the structure of a corresponding | compatible table typically. It is a timing chart for demonstrating operation | movement of a control apparatus.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Air conditioning apparatus 3, 3A, 3B Indoor unit 5 Air-conditioning outdoor unit 9, 9-1 to 9-6 Open showcase (open type low temperature showcase)
10 Cooling outdoor unit 20 Control device 50 Correspondence table A Open showcase set temperature (set temperature in the cabinet)
B Defrosting set temperature D Air conditioning set temperature T1 Defrosting operation start timing T2 Defrosting operation end timing T3 Internal temperature return timing

Claims (2)

In an air conditioner comprising an indoor unit provided in a store where an open type low-temperature showcase is installed, and an outdoor unit connected to the indoor unit by a refrigerant pipe,
During the period of the defrosting operation of the low temperature showcase, before the internal temperature of the low temperature showcase reaches the defrosting set temperature, which is the end temperature of the defrosting operation, a range higher than the internal temperature of the low temperature showcase At 1 to 2 degrees Celsius while lowering the air conditioning set temperature in the store,
After the defrosting operation is completed, the temperature in the store is returned to a predetermined temperature after the internal temperature of the low-temperature showcase has returned to the internal set temperature. When a plurality of the low temperature showcases are installed in the store and a plurality of the indoor units are provided,
In order to lower the temperature around the low-temperature showcase performing the defrosting operation by 1 ° C. to 2 ° C. in a range higher than the internal temperature of the low-temperature showcase, the air conditioning of the indoor units located around the low-temperature showcase The air conditioning apparatus according to claim 1, wherein the set temperature is lowered.

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