JPH10281615A - Cooling device for show case - Google Patents

Abstract

PROBLEM TO BE SOLVED: To control the high freshness of merchandize and to realize saving energy by controlling show cases and multi-freezers integrally and rationally. SOLUTION: A comprehensive controller 34 comprising an operating rate calculating part 3, a pressure setting value calculating part 4 and a freezer capability controlling part 5M is provided between the group of show cases and multi freezers 5M. The operating rate calculating part 3 calculates a solenoid valve operating rate at predetermined intervals, the pressure setting value calculating part 4 calculates the setting value regarding to the sucking refrigerant pressure of the group of the compressors 19 of the multi freezers 6M and the freezer capability controlling part 5M calculates the operating patterns for the group of compressors 19 based on the deviation between the predetermined value and the actual value of the pressure of the sucking refrigerant pressure. Here, the pressure setting value is being revised minimizing the power consumption that is the load to the show case and the freezer capability is equalized.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a showcase in which the flow of refrigerant is turned on / off by an electromagnetic valve and a multi-refrigerator in which the capacity is controlled by the selective operation of a plurality of compressors. The present invention relates to a showcase cooling device that controls to realize high freshness management and energy saving of a product.

[0002]

2. Description of the Related Art A conventional example will be described with reference to FIGS. FIG. 23 is a block diagram showing a configuration of a conventional example. The conventional example is roughly divided into a showcase group 1 and a multi refrigerator 6. One showcase group 1 is a group in which all of the showcases 1A, 1B, 1C,... (Hereinafter referred to as 1A...) Are arranged side by side in a store to form one group. Each evaporator 2
A, a showcase controller 34A for on / off control of the flow of the refrigerant to the evaporator 2A, an electromagnetic valve (not shown) as an operation end for turning on / off the flow of the refrigerant, and a Temperature sensors 14A for measuring the temperature of the blown air. Here, the reason why the location where the air was blown out was selected as the temperature measurement location in the showcase was that the location was not affected by the quantity of stored products and that the temperature based on the control was another factor. This is because it is convenient for control because the change appears most precedence. The multi-chiller 6 m has a compressor group 19,
The condenser 31, the low-pressure pressure sensor 7 for measuring the suction refrigerant pressure of the compressor group 19, and the compressor group 19 are selectively operated based on the difference between the measured pressure value and the set value to reduce the refrigeration function. A refrigerator controller 12 for controlling the refrigerator is provided.
Here, the compressor group 19 will be described later in detail with reference to FIGS. 24 and 25, but a plurality of compressors are connected in parallel, and the refrigeration function is controlled by selective operation thereof. .

Are connected in parallel with each other, and a compressor group 19 and a condenser 31 are connected in series with each other to form a refrigeration cycle. Each controller 3
4A... Controls the flow of the refrigerant to the corresponding evaporators 2A... Based on the deviation between the temperature signal from the corresponding temperature sensor 14A and the set value. The refrigerant is diverted after passing through the condenser 31 from the compressor group 19,
Circulates back to the compressor group 19 after flowing or being prevented from flowing into each evaporator 2A. here,
The control signal of each controller 34A is schematically shown so as to be input to the preceding stage of the corresponding evaporator 2A, and the on / off control of the flow of the refrigerant is shown.

FIG. 24 is a block diagram showing the configuration of a conventional refrigeration cycle in detail. This refrigeration cycle includes a compressor group 19 and a condenser 31 built in the multi refrigerator 6m.
And the evaporators 2A ... built in each showcase 1A ...
.. And a temperature expansion valve 32A. Here, the compressor group 19 is configured by connecting four compressors 9A, 9B, 9C, 9D in parallel, and the refrigerating function can be controlled by the selective operation of each compressor 9A.

FIG. 25 is a diagram showing the correspondence between the operation pattern of the compressor group 19 and the refrigerating function. Here, five driving patterns
(1), (2), (3), (4), and (5) show combinations of compressors operated in each operation pattern and the refrigeration function at that time. For example, in the case of the operation pattern (3), the compressors 9A and 9B are operated simultaneously (indicated by a circle), and the refrigerating function is 50% (the operation pattern (5) in which all the compressors are operated simultaneously). ) Is taken as 100%). In addition,
Here, the compressors have the same capacity (capacity), but in general, the number of components and each capacity can be freely selected.

In FIG. 23, in the control operation of the refrigeration cycle, in the showcase 1A, based on the deviation between the set value of the blown air temperature and the value measured by the temperature sensors 14A, the evaporator is operated via the controller 34A. 2A ...
On / off control of the flow of the refrigerant to the air conditioner. That is, when the deviation is plus (measured value ≧ set value), the solenoid valves 33A are opened (on), and when the deviation is minus (measured value <set value), the solenoid valves 33A are closed (off). The flow of the refrigerant to the evaporators 2A is turned on / off. In the multi-chiller 6m, the operation of the compressor group 19 is controlled via the controller 12 based on the difference between the set value of the suction refrigerant pressure of the compressor group 19 and the value measured by the pressure sensor 7, and the operation pattern shown in FIG. The refrigeration function is controlled by selecting from among the above. Here, the set value of the suction refrigerant pressure is a fixed value.

[0007]

In the conventional example, the temperature of the side of the showcase 1A is controlled via the individual controllers 34A based on the air temperature at the outlet, and the side of the multi-chiller 6m is the compressor. The capacity is controlled based on the deviation between the fixed set value and the actual value (output of the pressure sensor 7) with respect to the suction refrigerant pressure, and the showcase side and the multi-refrigerator side have independent control systems. That is, since the operation information on the showcase side is not directly reflected on the capacity control on the multi-chiller side, the responsiveness, stability, accuracy, and the like of the capacity control of the multi-chiller are inevitably reduced.
For this reason, the air temperature at the outlet greatly fluctuates, and the power consumption also increases. This is a factor that hinders maintenance of high freshness of products and energy saving.

Therefore, it is necessary to adopt a system in which the operation information on the showcase side is directly reflected in the capacity control on the multi-chiller side. In other words, the control is performed so as to balance the multi-refrigeration function power with the showcase load. It is to be. Therefore, a method of accurately and easily measuring the showcase load and the balance state between the showcase load and the multi-refrigeration function, that is, appropriate / excessive / deficient states, is important. Another issue closely related to the maintenance of high freshness of products and the realization of energy saving is that when the load of the showcase exceeds the refrigeration function during the showcase operation, a so-called overload condition occurs. The problem of the detection method and countermeasures, the problem of quick cooling after defrosting and the return to the original state, and the problem of limiting the number of simultaneously operated showcases so as not to increase the rated capacity of the multi-chiller more than necessary. There is.

An object of the present invention is to comprehensively and rationally control a showcase and a multi-refrigerator, to detect an overload state of a showcase, to deal with the problem, and to return after defrosting. It is an object of the present invention to provide a showcase cooling device that appropriately performs treatment and limits the number of simultaneously operated showcases, thereby realizing high freshness management and energy saving of products.

[0010]

SUMMARY OF THE INVENTION The present invention relates to a showcase for controlling the flow of refrigerant to an evaporator on / off via an electromagnetic valve based on a deviation between an air temperature at a predetermined location in a main body and a set value thereof. One or two or more, a multi-refrigerator whose capacity is controlled by the selective operation of a plurality of built-in compressors, and a comprehensive controller for controlling these showcases and the multi-refrigerator. A pressure set value calculation unit for obtaining a set value for the compressor suction refrigerant pressure of the multi-refrigerator based on the state; and a multi-compressor compressor based on a deviation between the obtained suction refrigerant pressure set value and the actual value. And a refrigeration function control unit for instructing selective operation.

The operating state of the showcase is represented by a solenoid valve operating rate which is a ratio of an ON time to a certain time of the solenoid valve, a cycle of ON / OFF of the solenoid valve, or an ON / OFF state of the solenoid valve. It can be represented by the air temperature drop rate at a predetermined location in the corresponding main body when the above operation is performed. Further, the present invention provides one or more showcases for controlling the flow of refrigerant to an evaporator on / off via an electromagnetic valve based on a difference between an air temperature at a predetermined location in the main body and a set value thereof, and a built-in case. A multi-refrigerator, the capacity of which is controlled by the selective operation of a plurality of compressors, and a general controller for controlling the showcase and the multi-refrigerator. A pressure set value calculating section for obtaining a set value for the suction refrigerant pressure for the compressor; and a refrigeration function for instructing a selective operation of the plurality of compressors based on a deviation between the set value and the actual value of the obtained suction refrigerant pressure. And a force control unit.

[0012] The operating conditions of the showcase can be turning on or off the illumination of the showcase, or the ambient temperature of the showcase. Further, the present invention further includes one or more showcases for controlling the flow of the refrigerant to the evaporator on / off via an electromagnetic valve based on a deviation between an air temperature at a predetermined location in the main body and a set value thereof, and A multi-refrigerator whose capacity is controlled by the selective operation of a plurality of compressors, and an integrated controller that controls these showcases and the multi-refrigerator. The integrated controller has a showcase load exceeding the multi-refrigeration function capability. Equipped with overload detection means for detecting that
It is a configuration.

Here, the overload detecting means operates based on a deviation between the suction refrigerant pressure for the compressor of the multi-refrigerator and its set value, or operates based on the air temperature at a predetermined location in the main body and the set value. It is preferable to operate based on the deviation of the solenoid valve operating ratio, which is the ratio of the ON time to the fixed time of the electromagnetic valve, and the set value thereof.

[0014] The integrated controller according to the present invention includes:
When the showcase load exceeds the multi-refrigeration function, according to a predetermined priority, an overload control means that cumulatively increases the showcase temperature set value by a certain time for a certain time is provided. is there. Therefore, in the present invention, the overload detecting means can detect that the cooling load of the showcase has exceeded the refrigerating function, and further, the overload controlling means accumulatively accords with a predetermined priority order. The overload state can be eliminated by increasing the temperature set value of the showcase for a fixed time within a range in which the freshness of the product can be maintained.

The overload detection is based on the fact that the average value of the suction refrigerant pressure of the inverter compressor incorporated in the refrigerator exceeds a set value for a certain period of time. The average value of the rate, or based on the fact that at least a certain number of the solenoid valves exceed the set value, or the deviation between the air temperature at a predetermined location in the main body, for example, the air outlet, and the set value indicates the predetermined value. It is based on what has been exceeded.

In addition, the overload control works so as to cumulatively increase the temperature of the showcase by a predetermined value within a range in which the freshness of the product can be maintained for a predetermined time in accordance with a predetermined priority order. The priority order is determined based on the machine numbers of the showcases, for example, in a formal manner, such as an arrangement order, in the order of lower cooling needs of the showcases, or equally in all the showcases. In particular, when the overload detection is based on the solenoid valve operation rate, the order is determined in the order of the showcase having the lowest solenoid valve operation rate.

Further, the present invention provides one or two of a showcase for controlling the flow of refrigerant to an evaporator on / off via an electromagnetic valve based on a deviation between an air temperature at a predetermined location in a main body and a set value thereof. The above consists of a multi-refrigerator whose capacity is controlled by the selective operation of a plurality of built-in compressors, and a general controller for controlling these showcases and the multi-refrigerator. The general controller is controlled based on the completion of defrosting. Is switched to a return process for rapidly returning to the cooling state, and then a switching unit is provided for returning the control to the normal mode based on the completion of the return.

Here, the return processing is to set the set value for the suction refrigerant pressure for the compressor of the multi-refrigerator to a value for rapid return, or to operate all the compressors in the multi-refrigerator at the same time, It is preferable to perform cooling with a refrigerating function or to change a set value for the air temperature at a predetermined location in the main body to a lower set value.

Therefore, according to the present invention, by switching the control to any one of the recovery processes based on the signal indicating the completion of the defrosting via the switching unit, the inside of the showcase where the temperature has increased due to the defrosting operation is performed. It can be quickly returned to the cooling state. Further, the present invention provides one or more showcases for controlling the flow of refrigerant to an evaporator on / off via an electromagnetic valve based on a difference between an air temperature at a predetermined location in the main body and a set value thereof, and a built-in case. A multi-refrigerator whose capacity is controlled by the selective operation of a plurality of compressors, and a total controller for controlling these showcases and the multi-refrigerator. It is preferable to provide a configuration in which an operating number limiting unit for suppressing the number of operating units is provided. In addition,
At the same time, as a method of suppressing the number of solenoid valves in the ON state to less than the predetermined number, the solenoid valves to be reached the predetermined number are stopped in the OFF state without being turned ON until one of the solenoid valves already in the ON state is turned OFF. Method, of the solenoid valves that should be turned on at the same time, the method of stopping the showcase solenoid valve in the off state in the order that the temperature of the product storage location is closer to its set value, of the solenoid valves that should be turned on at the same time, There are a method of stopping the solenoid valve of the showcase in the off state based on the determined priority, and a method of stopping the solenoid valve in the off state in the order of the lowest operation rate among the solenoid valves to be turned on at the same time.

Therefore, in the present invention, the number of solenoid valves which are simultaneously turned on is suppressed to less than a predetermined number by the operating number limiting unit, so that the rated capacity of the multi-refrigerator is suppressed to be reasonable when considered throughout the year. Can be.

[0021]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiments of the present invention will be described with reference to the following drawings. FIG.
FIG. 2 is a block diagram showing the configuration of the first embodiment. In FIG. 1, a comprehensive controller 34 for newly and comprehensively and rationally controlling the two is provided between the showcase group 1 and the multi refrigerator 6M. The multi refrigerator 6M has a configuration in which the controller 12 is removed from the conventional multi refrigerator 6m. The general controller 34 includes a solenoid valve operation rate calculation unit 3, a pressure set value calculation unit 4, and a refrigeration function force control unit 5M. The solenoid valve operation rate calculation unit 3 is configured to perform the operation for each solenoid valve 33A for a certain time before the certain time.
(Refer to FIG. 24), the solenoid valve operating rate, which is the ratio of the ON time, is determined. The pressure set value calculation unit 4 sets (updates) a set value (update) for the next fixed time with respect to the suction refrigerant pressure of the compressor group 19 operated on the side of the multi refrigerator 6M based on the obtained solenoid valve operation rate. Ask for. Refrigeration function control unit 5M
Sends a command to the compressor group 19 for an operation pattern (update) for the next fixed time based on the deviation between the obtained set value of the suction refrigerant pressure and the actual pressure. The refrigeration function controller 5M is functionally similar to the controller 12 of the related art.
However, by being incorporated into the general controller 34, the position in the apparatus is high.

Here, the pressure setting value is updated so that the power consumption becomes a necessary minimum, that is, the showcase load and the refrigerating function are equalized. Therefore, while checking the balance between the showcase load and the refrigeration function, it is determined whether the refrigeration function is insufficient, appropriate, or excessive with respect to the showcase load, and the pressure set value is optimally updated based on the judgment. . In addition, the balance between the refrigeration function and the showcase load is determined based on the operating rate of the solenoid valve of the showcase. In other words, when the operation rate of the solenoid valve is low,
When the refrigeration function is excessive with respect to the showcase load, when the operation rate of the solenoid valve is high, it is determined that the refrigeration function is insufficient. When the operation rate of the solenoid valve is appropriate, it is determined that the refrigeration function is appropriate. Here, the determination as to whether the operation rate of the solenoid valve is high, low, or appropriate is based on experience.

FIG. 4 is a graph showing the relationship between the pressure setting value and the showcase operation rate in relation to the updating of the pressure setting value. This is an empirical rule for updating the pressure set value, and this content is implemented by the pressure set value calculation unit 4 in FIG. In other words, (1) If the operating rate of at least one showcase (solenoid valve) is 90% or more, it is determined that the refrigeration function is insufficient, and the pressure set value is reduced (updated) by 0.01 MPa (0.1 kg / cm ² ). To increase the refrigeration function. (2) All showcase (solenoid valve) operating rates are 40 to 90
%, It is determined that the refrigeration function is appropriate, and the pressure set value is maintained as it is. (3) If the showcase (solenoid valve) operation rate is 90% or less for all units and at least one unit is 40% or less, the refrigeration function is judged to be excessive and the pressure set value is increased by 0.01 MPa (updated). To reduce the refrigeration function.

By the way, instead of determining the balance between the refrigeration function capacity and the showcase load based on the operation rate of the showcase solenoid valve as described above, when the solenoid valve is repeatedly turned on to turn on the flow of the refrigerant. The determination can be made based on the average descent rate of the air temperature at a predetermined location in the body of the corresponding showcase, or based on the average on / off cycle when the solenoid valve is repeatedly turned on / off. . These other determination methods will be described below.

First, the balance between the refrigerating function and the showcase load is determined based on the average descent speed of the air temperature at a predetermined location within the main body of the showcase, for example, at the air outlet. Is used. This general controller 34X is a first modified example of the general controller 34 in FIG. 1, and a temperature lowering speed calculator 3X is used instead of the solenoid valve operation rate calculator 3 in the general controller 34. Based on the operating signal of the solenoid valve of each showcase and the temperature signal of the blown air, the temperature drop speed calculating unit 3X repeatedly turns on the solenoid valve at a certain time before the certain time, and turns on the flow of the refrigerant. The average descent speed of the temperature of the blown air of the corresponding showcase when turned on is determined.

It is possible to determine whether the refrigeration function is excessive, insufficient, or appropriate for the showcase load, depending on whether the average descending speed of the air temperature at the outlet is large or small. This is performed based on the rule of thumb shown in FIG. FIG. 5 is a diagram showing the relationship between the pressure setting value and the descending speed of the blown air temperature in relation to the updating of the pressure setting value, and this content is executed by the pressure setting value calculation unit 4 in FIG. That is, (1) If at least one of the units has a descent speed below the lower limit value, it is determined that the refrigerating function is insufficient, and the pressure setting value is lowered to increase the refrigerating function. (2) If the descent speed is within the set range for all showcases, it is determined that the refrigeration function is appropriate, and the pressure set value is maintained as it is. (3) If at least one of the units has a descent speed equal to or higher than the upper limit value, it is determined that the refrigerating function is excessive, and the set pressure is increased to decrease the refrigerating function.

In the method of determining the balance between the refrigerating function and the showcase load based on the average ON / OFF cycle when the solenoid valve of the showcase is repeatedly turned ON / OFF,
The general controller 34Y of FIG. 3 is used. This is a second modified example of the general controller 34 in FIG. 1, and an on / off cycle calculating unit 3Y is used instead of the solenoid valve operation rate calculating unit 3 in the general controller 34. The on / off cycle calculation unit 3Y calculates an average on / off cycle when each solenoid valve is repeatedly turned on / off at a certain time before a certain time, based on the solenoid valve operation signal of each showcase. You can ask.

Now, it can be determined whether the refrigeration function is excessive, insufficient or appropriate for the showcase load depending on whether the average ON / OFF cycle is small or large, and the determination is shown in FIG. This is done based on rules of thumb. FIG.
FIG. 4 is a diagram showing a relationship between the pressure set value and the ON / OFF cycle of the solenoid valve in relation to the update of the pressure set value, and the contents thereof will be implemented by the pressure set value calculation unit 4 in FIG. In other words, (1) If the on / off cycle of at least one unit exceeds the upper limit, it took more time for cooling. Therefore, it was determined that the refrigeration function was insufficient, and the pressure setting value was lowered to reduce the refrigeration function. Increase power. (2) For all showcases, if the ON / OFF cycle is within the set range, the refrigeration function is judged to be appropriate and the pressure set value is maintained as it is. (3) If at least one unit has an on / off cycle that is less than the lower limit, cooling has been performed in a shorter period of time, so it is determined that the refrigeration function is excessive. Decrease.

The second embodiment will be described with reference to the block diagram showing the configuration of FIG. In the figure, in the form interposed between the showcase group 1 and the multi refrigerator 6M,
A general controller 38 for comprehensively and rationally controlling the two is provided. The general controller 38 includes a pressure set value calculator 48 and a refrigeration function controller 5M. The function of the pressure set value calculator 48 is as follows. In general, the cooling load on the showcases 1A... Is reduced by turning on and off the lights (fluctuations in power consumption) and changes in the ambient temperature of the showcases 1A. Change. Therefore, it is necessary to increase or decrease the refrigeration function according to this. For that purpose, the refrigeration function control unit 5 is controlled based on the set value related to the pressure from the pressure set value calculation unit 48 and the actual value of the pressure from the pressure sensor 7.
Compressor group 19 built in multi refrigerator 6M by M
Perform selective operation of.

The pressure set value calculating section 48 is based on the command signals for turning on and off the lights 60A provided in each showcase 1A and the temperature signals from the temperature sensors 61A for measuring the ambient temperature. A pressure set value relating to the suction refrigerant pressure of the compressor group 19 described later is calculated and obtained. Each of the temperature sensors 61A is connected to each of the showcases 1A.
The pressure set value calculator 48 calculates the average value of the temperature signals from the respective pressure set values before calculating the pressure set value. Here, since the ambient temperature is generally common except when the installation environment is particularly different, it can be represented by any one of the temperature sensors 61A. This pressure set value is transmitted to the refrigeration function control unit 5M, and as described in detail below, the operation pattern of the compressor group 19 is determined based on the deviation between the pressure set value and the actual pressure value, that is, the selective operation is performed. Do it.

FIG. 8 is a diagram showing the correspondence between the ambient temperature and the pressure set value when the showcase lighting is turned on in relation to the update of the pressure set value, and FIG. 9 is the diagram showing the surroundings when the showcase lighting is turned off in the update of the pressure set value. It is a correspondence diagram of a temperature and a pressure set value. In FIG. 8, when the lighting is turned on, the ambient temperature of the showcase is 10 to
Corresponding to 15, 15-20, 20-22, ... 30-35 (° C), the pressure set values are 3.0, 2.8, 2.6 ... 1.6, respectively.
(Kgf / cm ² ), and in FIG.
When the lights are off, the ambient temperature of the showcase is 10-15,
Corresponding to 15 to 20, 20 to 22,..., 30 to 35 (° C.), the pressure set value is determined as 3.5, 3.3, 3.1,... 2.1 (kgf / cm ² ).

A third embodiment will be described with reference to FIGS. 10 and 11. The third embodiment and the following fourth and fifth embodiments all relate to overload detection. FIG. 10 is a block diagram showing the configuration of the third embodiment, and FIG. 11 is a block diagram showing the internal configuration of the integrated controller in detail. In FIG. 10, a general controller 35 is provided between the showcase group 1 and the multi refrigerator 6M. The integrated controller 35 includes an overload detection unit 43
, An overload control unit 46 and a refrigeration function control unit 5M. The overload detection unit 43 detects that the cooling load of the showcase has exceeded the refrigerating function, and performs a detection operation at regular intervals. When the cooling load of the showcase exceeds the refrigerating function, the overload control unit 46 accumulatively sets the temperature setting value of the showcase within a range for maintaining the freshness of the product for a predetermined time in accordance with a predetermined priority order. It works to raise the value by a certain amount and has a function to eliminate the overload condition. The refrigeration function control unit 5M sets a set value (fixed value) of the suction refrigerant pressure.
The operation pattern for the compressor group 19 of the multi-chiller 6M can be determined based on the deviation between the multi-chiller 6M and the actual value (the output value of the pressure sensor 7).

In FIG. 11, the overload detecting section 43 includes a pressure average value calculating section 50 and a comparing section 51. Based on the pressure signal (compressed refrigerant pressure for the compressor) from the pressure sensor 7, the average pressure value calculation unit 50 calculates the average value of the pressure for a certain period of time. The comparison unit 51 compares the average value of the pressure for a certain period of time with the set pressure value for each certain period of time, and when the average value for a certain period of time exceeds the set pressure value, detects (determines) overload and outputs a detection signal. . The overload control unit 46 includes a command unit 56 and a priority setting unit 57. The command unit 56 issues a command to cumulatively increase the temperature set value for the showcase by a certain value within a range for maintaining the freshness of the product for a certain time based on the detection signal. The priority order setting section 57 determines in advance the priority order of the showcase to which the command signal is transmitted, and the priority order is formally determined based on the machine number of the showcase, or the priority of the showcase is determined. The cooling order is determined in ascending order of necessity, that is, the order in which even if the degree of cooling is slightly reduced, the freshness of the product is less affected. For example, the order is "vegetables", "daily products", "fresh fish / meat". The command unit 56 sequentially increases the temperature set value by 1 ° C. every 15 minutes, for example, every 15 minutes for the showcase as long as an overload condition is detected according to the predetermined priority order as described above. Go. Here, depending on the situation, the showcases may be sequentially raised one by one, or the showcases may be sequentially raised two by two. In short, it depends on the setting of the priority order. Alternatively, the priority order may be made equal, and the temperature set values of all showcases may be increased by 1 ° C. for 3 hours at a time. If the detection signal of the comparing section 51 is stopped at the next detection time by the overload elimination operation based on the command signal and the overload state is eliminated, the output of the command signal of the overload control section 56 is stopped.

FIG. 12 shows the fourth embodiment and its modification.
This will be described with reference to FIGS. FIG. 12 is a block diagram showing the configuration of the fourth embodiment, and FIG. 13 is a block diagram showing the internal configuration of the integrated controller in the fourth embodiment in detail. 12, the general controller 36 includes an overload detection unit 44, an overload control unit 47, and a refrigeration function control unit 5M. Next, in FIG. 13, the overload detection unit 44 includes an operation rate calculation unit 52 and an operation rate average value calculation unit 53.
And a comparing unit 54. The overload control unit 47 includes a command unit 56 and a priority order specifying unit 58. Driving rate calculator 52
Receives the solenoid valve operation signal output from the controller 34A of each showcase 1A (see FIG. 12), and calculates the operation rate (percentage of the on-time of the solenoid valve with respect to the certain time) during that period at regular intervals. . Based on each driving rate, the driving rate average value calculation unit 53 obtains the average value. Comparison unit 54
Compares this driving rate average with its corresponding setpoint,
When the average operation rate exceeds the set value, a detection signal is output as overload. Now, the priority order specifying unit 58 receives each operation rate calculated by the operation rate calculation unit 52 and determines the order of the showcases with the lowest operation rates, that is, the order in which the refrigeration function has a margin. When receiving the detection signal, the command unit 56 sets the command signal from the priority order specifying unit 58 in the order of the showcases with the lowest driving rates, that is, the temperature set value of the showcase for a fixed time within a range for maintaining the freshness of the product. Outputs a command signal to increase the value. If the overload state is not resolved even after a predetermined time, for example, 30 minutes, after the command, the same command signal is transmitted to the showcase in a form of accumulating sequentially according to the priority order. If the overload state is resolved at the time of the next overload detection, the output of the command signal is stopped.

The general controller 37 in the modification will be described with reference to a block diagram showing the internal configuration of FIG. 14 in detail. In FIG. 14, the overload detection unit 45
Is composed of a driving rate calculation unit 52, a comparison unit 54, and a determination unit 55. The operation rate calculation unit 52 receives the solenoid valve operation signal output from the controller 34A of each showcase 1A. The comparing unit 54 compares each of the operation rates with the corresponding set value, and outputs a signal when the operation rate exceeds the set value. In the determination unit 55, the comparison unit 5
If the number of signals output from the control unit 4 becomes equal to or more than a predetermined number, for example, if at least one signal is output (if even one showcase exceeds the corresponding set value), an overload condition is set. Judge and output the detection signal. Instead of one showcase, when there are at least two,
It is also possible to determine that an overload state has occurred and output a detection signal. The operation of the overload control unit 47 in response to this
The description is omitted because it is the same as that of FIG.

The fifth embodiment will be described with reference to a block diagram showing the configuration of FIG. 15 and a block diagram showing the internal configuration of the general controller of FIG. 16 in detail. FIG.
, A general controller 38 is provided between the showcase group 1 and the multi refrigerator 6M. The integrated controller 38 includes a new overload detection unit 48, the same overload control unit 46 and refrigeration function control unit 5M as in the third embodiment. As will be described in detail later, the overload detecting unit 48 is configured such that a deviation between an air temperature detected by a predetermined position in the main body, for example, each temperature sensor 14A of the air outlet, and a set value thereof exceeds a predetermined value. A detection method is performed based on the fact that the detection operation is performed at regular time intervals. The overload control unit 46 and the refrigeration function control unit 5M are the same as those in the third embodiment described above, and thus description thereof will be omitted.

In FIG. 16, the overload detecting section 48 includes a comparing section 54 and a determining section 55. The comparison unit 54 determines whether the air temperature at the outlet of each showcase is
4A... (See FIG. 15), a deviation is obtained by comparing with a set value, and when this deviation exceeds a predetermined value, it is detected as an overload state and a signal is output. When the number of signals output from the comparing section 54 is equal to or more than a predetermined number, the determining section 55 outputs, for example, at least one signal (even in one showcase, the air temperature at the outlet corresponds to the number of signals). If the set value is exceeded), it is determined that an overload condition has occurred and a detection signal is output. Showcase 1
Instead of the units, when at least two units are set, it may be determined that an overload state is present and a detection signal may be output. The operation of the overload control unit 46 in response to this is the same as that in FIG. 11 of the third embodiment, and a description thereof will be omitted.

The sixth to eighth embodiments will be described below. Each of these embodiments relates to rapid return cooling (so-called pull-down) after defrosting. FIG. 17 is a block diagram showing the configuration of the sixth embodiment. Comprehensive controller 21
Is a block diagram of the first embodiment shown in FIG. 1 and has a configuration in which a switching unit 10 is inserted between the pressure set value calculation unit 4 and the refrigeration function control unit 5M. The switching unit 10 is a switch mechanism that can selectively take two positions as shown schematically, and takes a position of a broken line (switch) based on a defrosting end signal of a broken line display, and returns to a solid line display. Based on the completion signal, the position of the solid line is taken (switched). Here, the defrost end signal is a signal output when the defrost is completed, and the return completion signal is a signal indicating the completion of the return to the cooling state. There is a method.

During defrosting, the entire showcase stops operating, so that the integrated controller 21 does not operate. When the defrost is completed, a return pressure set value (for example, 0.1 kgf / cm ² ) is input to the refrigeration function force control unit 5M via the switching unit 10 based on the defrost end signal output in response thereto, The compressor group 19 is selectively operated so as to increase the refrigerating function, and the showcase whose temperature has risen due to the defrosting process is quickly returned to the cooling state (return mode). Next, based on the return completion signal, the switching unit 10 switches to the solid line side to return the control to the normal mode.

Here, the return procedure in the sixth embodiment is to switch the suction refrigerant pressure for the compressor to the return pressure set value. However, in the following seventh and eighth embodiments, the return procedure is different. Return action is taken. Also, the determination of the return completion will be described later in detail because there are various methods. FIG.
FIG. 14 is a block diagram showing a configuration of a seventh embodiment. This seventh
In the embodiment, the integrated controller 22 is used. In this case, the return process is performed by switching the operation pattern command to a predetermined return operation pattern command, thereby performing a predetermined selective operation of the compressor group 19 to execute the showcase. Quickly return to cooling. Next, as in the sixth embodiment, based on the return completion signal, the switching unit 10 switches to the solid line side to return the control to the normal mode. As a modification of the seventh embodiment, although not shown here, the compressor group 19
Operating all the compressors at the same time, that is, cooling with the maximum refrigeration function power can be the return treatment.

FIG. 19 is a block diagram showing the configuration of the eighth embodiment. In the eighth embodiment, the integrated controller 23
Is used, and the return process is performed by changing the set value related to the air temperature at the outlet in the showcase to a lower set value. Specifically, the temperature setting unit 11 is provided, and based on the defrost end signal, For example, for the showcase 1A, the set value of the individual controller 34A is changed to a set value lower than the previous value, for example, -4 ° C to -5 ° C, and a deviation from the output of the temperature sensor 14A is obtained. Then, the showcase 1A is quickly returned to the cooling state.
The same applies to the other showcases 1B. next,
Based on a return completion signal generated when all deviations become zero, that is, when the air temperatures at all the outlets reach the updated set temperature, the set values before the change are returned.

The output means of the return completion signal is shown in FIG.
This will be described with reference to FIG. FIG. 20 is a block diagram of a first example of the return completion signal generating means, FIG. 21 is a block diagram of the second example thereof, and FIG.
It is a block diagram of an example of. The first to third examples of the generating means can be arbitrarily applied to any of the sixth to eighth examples.

In FIG. 20, the generating means is a timer 15
In this method, a recovery completion signal is output after a predetermined set time (for example, one hour), starting from the input point of the defrost end signal. The completion of the recovery is mechanically determined (assumed) when the set time has elapsed. of course,
The setting time is determined with sufficient empirical support.

In FIG. 21, the output means is a counter 16
In this method, a return completion signal is output after all the solenoid valves have been turned off at least a set number of times (for example, three times), starting from the input point of the defrost end signal. By turning off all solenoid valves at least the set number of times,
That is, it is determined (assumed) that the return to the cooling state is completed. Of course, how to determine the number of off-settings is done with sufficient empirical support.

In FIG. 22, the output means is a temperature monitor 1
7, a method of outputting a return completion signal after the air temperature of all the outlets becomes equal to or lower than a set value (for example, −4 ° C.) (returns) from the input point of the defrost end signal as a starting point. . When the air temperatures of all the outlets have become equal to or lower than the set value (returned), it is determined (assumed) that the return to the cooling state is completed. Note that, instead of the air temperature of the air outlet, the average air temperature for a certain period (for example, 15 minutes) can be used, whereby the possibility of erroneous return determination based on the fluctuation of the air temperature can be prevented.

Although not shown here, by providing an operating number limiter in the integrated controller, when more than a predetermined number of solenoid valves in the showcase should be turned on at the same time, any of the following methods is used. The number of solenoid valves that are simultaneously turned on can be suppressed to less than a predetermined number. The purpose is to reduce the rated capacity of the multi refrigerator 6M.
In other words, as a result of the fact that the rated capacity of the refrigerator is selected on the basis of the peak load in midsummer, the capacity becomes excessive when considered throughout the year, and the occupied space and equipment cost become unnecessarily large and wasted. It is.

The solenoid valves which should reach the predetermined number are kept off without being turned on until one of the solenoid valves already on is turned off. In other words, according to the actual driving situation at that time, the showcase which should reach the predetermined number after the next driving is a method of continuing the operation stop. At the same time, among the solenoid valves to be turned on, the solenoid valves of the showcase are kept off in the order in which the temperature of the product storage location is closer to the set value. That is, the operation is stopped from a sufficiently cooled showcase.

At the same time, among the solenoid valves to be turned on, the solenoid valves in the showcase are kept off based on a predetermined priority. For example, there is a method in which operation is preferentially stopped from a showcase of a product which is relatively acceptable without cooling. At the same time, among the solenoid valves to be turned on at the same time, the solenoid valves are kept in the off state in ascending order of the operation rate. In other words, the operation is stopped in order from a showcase having a track record of relatively sufficiently cooling.

[0049]

According to the present invention, the following excellent effects can be expected. (1) For example, the operating rate of the solenoid valve, the rate of decrease in air temperature at a predetermined location in the main body of the showcase,
Based on one of the off cycles, information on the multi-refrigeration function power for each assumed showcase load and information on the suction refrigerant pressure for the compressor on the multi-chiller side are collected, and the showcase load is approximated. The operation of the showcase is comprehensive so that the
It is done rationally. Therefore, the power consumption of the multi-chiller can be minimized to save energy, and the fluctuation range of the air temperature at a predetermined location of the showcase, for example, at the outlet, can be reduced to increase the product price. Freshness management can be realized.

(2) Considering the turning on / off of the lighting provided in each showcase, that is, the load fluctuation of the power consumption related to the lighting, another factor is the ambient temperature of each showcase, that is, the external temperature. The operation of the multi-refrigerator is reasonably operated simply in consideration of the load fluctuation of the invading heat quantity, so as to match the cooling load.Therefore, to support energy saving and reduce the fluctuation range of the showcase temperature It can support high-freshness management of products based on this.

(3) Paying attention to the index “overload state”,
Through the overload detection and overload control (elimination operation), the operation of the showcase can be rationally controlled. Therefore, it is possible to cope with environmental changes such as ambient temperature and humidity, and it is possible to minimize the refrigerating function, thereby supporting energy saving and management of high freshness of products. There are various methods for the overload detection method and the overload control method, all of which are simple and practical, and the optimum method can be selected according to the situation.

(4) When the inside of the showcase is returned to the original cooling state before the defrosting after the defrosting, the return time can be shortened, and therefore, the freshness of the product can be maintained. In addition, since there are various types of options for the return procedure and the return completion determination, it is possible to take an optimal mode according to the actual situation at that time. (5) By providing the operating number limiter, if more than a predetermined number of solenoid valves in the showcase should be turned on at the same time, it is possible to reduce the number of solenoid valves that are turned on simultaneously by any of the methods described above to less than the predetermined number. it can. As a result, the multi refrigerator 6M
Can be suppressed, and the occupied space and device cost can be reduced.

[Brief description of the drawings]

FIG. 1 is a block diagram showing a configuration of a first embodiment according to the present invention;

FIG. 2 is a block diagram showing a first modification of the integrated controller according to the first embodiment;

FIG. 3 is a block diagram showing a second modification of the integrated controller in the first embodiment.

FIG. 4 is a diagram showing a correspondence between a pressure set value and a showcase operation rate in relation to updating of a pressure set value.

FIG. 5 is a diagram showing a relationship between the pressure setting value and the descending speed of the blown air temperature according to the update of the pressure setting value.

FIG. 6 is a diagram showing a relationship between a pressure set value and an on / off cycle of a solenoid valve according to the update of the pressure set value

FIG. 7 is a block diagram showing a configuration of a second embodiment according to the present invention.

FIG. 8 is a diagram showing a correspondence between an ambient temperature and a pressure set value when the lighting is turned on.

FIG. 9 is a diagram showing a correspondence between an ambient temperature and a pressure set value when the light is turned off.

FIG. 10 is a block diagram showing a configuration of a third embodiment according to the present invention.

FIG. 11 is a block diagram showing an internal configuration of a general controller according to a third embodiment.

FIG. 12 is a block diagram showing a configuration of a fourth embodiment according to the present invention.

FIG. 13 is a block diagram showing an internal configuration of a general controller according to a fourth embodiment.

FIG. 14 is a block diagram showing a configuration in a modification of the fourth embodiment.

FIG. 15 is a block diagram showing a configuration of a fifth embodiment according to the present invention.

FIG. 16 is a block diagram showing an internal configuration of a general controller according to a modification of the fifth embodiment.

FIG. 17 is a block diagram showing a configuration of a sixth embodiment according to the present invention.

FIG. 18 is a block diagram showing a configuration of a seventh embodiment according to the present invention.

FIG. 19 is a block diagram showing a configuration of an eighth embodiment according to the present invention.

FIG. 20 is a block diagram of a first example of a return completion signal generating means;

FIG. 21 is a block diagram of a second example of the return completion signal generating means;

FIG. 22 is a block diagram of a third example of the return completion signal generating means;

FIG. 23 is a block diagram showing a configuration of a conventional example.

FIG. 24 is a block diagram showing the configuration of a conventional refrigeration cycle in detail.

FIG. 25 is a diagram showing the correspondence between the operation pattern of the compressor group and the refrigeration function.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 Showcase group 1A, 1B, 1C Showcase 3 Solenoid valve operation rate calculation part 3X Temperature drop speed calculation part 3Y Solenoid valve ON / OFF cycle calculation part 4,48 Pressure set value calculation part 5 Refrigeration function power control part 6M Multi refrigeration Machine 7 Pressure sensor 10 Switching unit 11 Temperature setting unit 15 Timer 16 Counter 17 Temperature monitor 19 Compressor group 21, 22, 23 General controller 31 Condenser 33A, 33B, 33C Solenoid valve 34, 34X, 34Y General controller 34A, 34B, 34C controller (individual showcase) 35, 36, 37, 38 General controller 43, 44, 45, 48 Overload detection unit 46, 47 Overload control unit 50 Pressure average value calculation unit 51, 54 Comparison unit 52 Operating rate calculation unit 53 Average operating rate calculation unit 55 Judgment unit 56 Designation unit 57 Priority order setting unit 58 Priority order designation section 60A, 60B, 60C Lighting 61A, 61B, 61C Temperature sensor (for ambient temperature)

Claims (17)

[Claims] 1. A showcase for controlling the flow of a refrigerant to an evaporator on / off via an electromagnetic valve based on a deviation between an air temperature at a predetermined position in a main body and a set value thereof;
It consists of a multi-refrigerator whose capacity is controlled by the selective operation of a plurality of built-in compressors, and a general controller for controlling these showcases and the multi-refrigerator.
A pressure set value calculation unit for obtaining a set value for the suction refrigerant pressure for the compressor of the multi refrigerator; a command for selectively operating the plurality of compressors based on a deviation between the obtained set value of the suction refrigerant pressure and the actual value; And a refrigeration function controller. 2. The cooling device according to claim 1, wherein the operating state of the showcase is a solenoid valve operating rate which is a ratio of an on-time to a certain time of the solenoid valve. 3. The showcase refrigeration system according to claim 1, wherein the operating state of the showcase is an ON / OFF cycle of a solenoid valve. 4. The showcase according to claim 1, wherein the operating state of the showcase is an air temperature drop rate at a predetermined position in the main body when the solenoid valve is turned on. Refrigeration equipment. 5. One or more showcases for controlling the flow of refrigerant to an evaporator on / off via an electromagnetic valve based on a difference between an air temperature at a predetermined location in the main body and a set value thereof,
It consists of a multi-refrigerator whose capacity is controlled by the selective operation of a plurality of built-in compressors, and a general controller for controlling these showcases and the multi-refrigerator, and this general controller is based on the operating conditions of the showcase,
A pressure set value calculation unit for obtaining a set value for the suction refrigerant pressure for the compressor of the multi refrigerator; a command for selectively operating the plurality of compressors based on a deviation between the obtained set value of the suction refrigerant pressure and the actual value; And a refrigeration function controller. 6. The cooling device according to claim 5, wherein the operating condition of the showcase is turning on or off the illumination of the showcase. 7. The cooling device according to claim 5, wherein the operating condition of the showcase is an ambient temperature of the showcase. 8. A showcase for controlling on / off of a flow of a refrigerant to an evaporator through an electromagnetic valve based on a difference between an air temperature at a predetermined position in the main body and a set value thereof, and
It consists of a multi-chiller whose capacity is controlled by the selective operation of multiple built-in compressors, and an integrated controller that controls these showcases and multi-chillers. A showcase cooling device comprising an overload detecting means for detecting the occurrence of a load. 9. The cooling device according to claim 8, wherein the overload detecting means operates based on a deviation between the suction refrigerant pressure for the compressor of the multi-refrigerator and its set value. Case cooling device. 10. The cooling device according to claim 8, wherein the overload detecting means operates based on a deviation between an air temperature at a predetermined position in the main body and a set value thereof. . 11. The cooling device according to claim 8, wherein the overload detecting means operates based on a deviation between a solenoid valve operating rate, which is a ratio of an on-time to a predetermined time of the solenoid valve, and a set value thereof. A showcase cooling device, comprising: 12. The cooling device according to any one of claims 8 to 11, wherein the integrated controller accumulatively accumulates according to a predetermined priority order when the showcase load exceeds the multi-refrigeration function power. A showcase cooling device comprising overload control means for increasing a set temperature of a showcase by a certain value for a certain period of time. 13. One or more showcases for controlling the flow of refrigerant to an evaporator on / off via an electromagnetic valve based on a deviation between an air temperature at a predetermined location in the main body and a set value thereof,
It consists of a multi-chiller whose capacity is controlled by the selective operation of a plurality of built-in compressors, and an integrated controller that controls these showcases and the multi-chiller. This integrated controller rapidly controls the operation based on the completion of defrosting. A showcase cooling device comprising: a switching unit that switches to a return process for returning to a cooling state, and then returns control to a normal mode based on completion of the return. 14. The cooling apparatus according to claim 13, wherein the return processing is to set a set value for the suction refrigerant pressure for the compressor of the multi-refrigerator to a value for rapid return. Case cooling device. 15. The showcase cooling device according to claim 13, wherein the return processing is to simultaneously operate all the compressors in the multi refrigerator. 16. The showcase cooling device according to claim 13, wherein the return processing is to change a set value for the air temperature at a predetermined position in the main body to a lower set value. . 17. One or more showcases for controlling the flow of a refrigerant to an evaporator on / off via an electromagnetic valve based on a deviation between an air temperature at a predetermined location in the main body and a set value thereof;
It consists of a multi-refrigerator whose capacity is controlled by the selective operation of a plurality of built-in compressors, and a general controller that controls these showcases and the multi-refrigerator. A showcase cooling device, comprising: an operating number limiting unit that suppresses the number of operating units to less than one.