JP2001221564A - Showcase management device and showcase system - Google Patents

Abstract

(57) [Summary] [PROBLEMS] To enable efficient diagnosis or prediction of a failure of a showcase or a refrigerator. A control device (30) includes sensors (18, 20, 2).
2 based on the detection result, the daily fluctuation amount (pressure fluctuation amount) of the pressure on the discharge side of the refrigerator 5 and the time required for lowering the temperature of the cool air to a predetermined temperature (reduction time) for each day. The amount of fluctuation (the amount of time difference fluctuation), the amount of daily fluctuation (the time difference fluctuation) of the difference (time difference) between the time required to lower the internal temperature to the predetermined temperature and the time of reduction,
Is calculated. At the time of failure determination, the ratio of the value of each item obtained on the day to the value (reference value) of each item obtained at the beginning of operation is calculated. Then, the magnitude of the mutual ratio is determined. Then, the alarm device 35 is notified of the failure factor associated with the largest item.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a showcase management apparatus and a showcase system capable of efficiently performing fault diagnosis and prediction of a showcase and a refrigerator.

[0002]

2. Description of the Related Art Showcases and the like provided in stores such as supermarkets and convenience stores are provided with a function of diagnosing equipment failure. As such a failure diagnosis technique, there is a technique of constructing a database in which data relating to equipment is stored, and empirically evaluating the operating state of the equipment and predicting failure using the data registered in the database. As a failure diagnosis technique using such a technique, for example, the following techniques are available.

[0003] Japanese Patent Application Laid-Open No. 10-238920 discloses an apparatus configured to evaluate the current operation state of a device by comparing data relating to the current operation state of the device with corresponding past data in a database. Is disclosed. Also, Japanese Patent Application Laid-Open No. 10-26750
No. 9 discloses a device operation state management device configured to predict the time when a device will fail based on data on the current operation state of the device and corresponding past data in a database. ing.

[0004] The database used in such technology relates to past operating conditions, and is constructed by classifying and storing data relating to the operating conditions of devices for each operating condition of the device from which the data was obtained. It is supposed to.

[0005]

However, in the above prior art, when the contents of the database are insufficient, the evaluation of the operating state and the failure prediction tend to be inaccurate. In particular, it is not possible to accurately evaluate the operation state of the equipment and predict failures, for example, due to the influence of fluctuations in the ambient temperature or when multiple failures occur simultaneously. To enable accurate evaluation and prediction, it is necessary to enhance the contents of the database, but this requires a great deal of effort. In addition, since an inference mechanism and the like must be mounted as needed, it cannot be said that the system is efficient.

[0006] In particular, when not only a showcase but also various devices arranged in a store such as an air conditioner and lighting are controlled collectively for various devices in the store,
An enormous amount of data must be stored for each device type, and the database becomes enormous.

[0007] The present invention has been made in view of the above, and an object of the present invention is to provide a showcase management device and a showcase system capable of efficiently diagnosing or predicting a failure of a showcase or a refrigerator.

[0008]

SUMMARY OF THE INVENTION The present invention has been made to achieve the above object. According to the first aspect of the present invention, a refrigerant is cooled by heat exchange in an evaporator. In a showcase management device that manages a showcase that cools a storage room in which goods are displayed and stored by the cool air, data indicating the temperature of the storage room (hereinafter, referred to as “inside temperature”) is input. Frost detection means for detecting frost in the evaporator based on the input data, and frost formation for notifying that frost has occurred when the frost detection means detects frost. Notification means,
The showcase management apparatus characterized by having is provided.

The invention described in claim 2 is the first invention.
According to the showcase management device described in the above, the frost detection means obtains the rate of change of the internal temperature, if the rate of change exceeds a predetermined range, it is determined that frost has occurred It is characterized by the judgment.

[0010] Further, the invention described in claim 3 is based on claim 2.
Wherein the frost detection means is configured to calculate the rate of change based on a temperature in the refrigerator at the beginning of the operation of the showcase.

Further, according to the present invention, a refrigerator for liquefying the refrigerant and an evaporator are provided, and the evaporator exchanges heat with the refrigerant supplied from the refrigerator to cool the refrigerant. And a showcase that cools a storage room in which goods are displayed and stored with the cool air, an internal temperature detection unit that detects a temperature in the storage room, and a detection result of the internal temperature detection unit. Claims 1, 2, or 3
And a showcase management device according to (1).

According to the fifth aspect of the present invention, a refrigerator that compresses and liquefies a refrigerant by a compressor and a condenser, and cools air by exchanging heat in the evaporator with the refrigerant supplied by the refrigerator. And a showcase that manages a storage case in which goods are displayed and cooled by blowing out the cool air from an air outlet, and a showcase management device that manages the pressure on the discharge side of the refrigerator, the showcase. Failure estimating means for inputting data indicating the temperature of the cool air blown to the container and the temperature of the storage (hereinafter referred to as “inside temperature”), and estimating the occurrence of a failure based on the input data; And a notifying means for notifying the estimation result of the failure estimating means.

[0013] The invention described in claim 6 is the invention according to claim 5.
The failure estimating means may include an amount of change in pressure on the discharge side of the refrigerator for each predetermined period (hereinafter, referred to as “pressure change amount”) and an amount of cold air in a predetermined specific situation. Of the time required for lowering the temperature of the device to a predetermined temperature (hereinafter referred to as “reduction time”) for each predetermined period (hereinafter “reduction time fluctuation amount”)
And a difference (hereinafter, referred to as a "time difference fluctuation amount") of a difference (hereinafter, referred to as "time difference") between a time required for lowering the internal temperature to a predetermined temperature and the lowering time in the specific situation (hereinafter, referred to as a "time difference"). )), The fluctuation amount calculating means for obtaining the pressure fluctuation amount, the reduction time fluctuation amount and the time difference fluctuation amount, and the fluctuation amount at a predetermined time as a reference value, The value and the ratio of the variation obtained during the period for which the failure is estimated are calculated for each of the three items, the variation ratio calculating means to be determined, and the three items determined by the variation ratio calculating means. And a ratio determining means for determining a relative magnitude relationship between the values of the ratios of the ratios. Wherein the but is intended to notify the failure factors related to the largest was item.

The invention described in claim 7 is the same as the claim 6.
Wherein the notifying means has storage means for storing related information defining the correspondence between the three items and the failure factors, and based on a result of the determination by the ratio determining means. By referring to the related information, the failure factor associated with the item having the largest value of the ratio is obtained and the content thereof is reported.

The invention according to claim 8 is the same as the invention according to claim 7.
According to the showcase management device described in the above, the notification means, when the ratio of the pressure fluctuation amount is the largest, as a failure factor, clogging of the condenser, of direct sunlight irradiation, At least one is notified, and when the ratio of the amount of change in the reduction time is the largest, the failure factors include a shortage of refrigerant, turbulence in cooling air, and an excessively high temperature around the showcase. And, to notify at least one of the clogging of the condenser, and the clogging of the blower port, when the ratio of the time difference fluctuation amount is the largest, as the failure factor, It is characterized in that at least one of the clogging of the air outlet and the turbulence of the cool air is notified.

The invention according to claim 9 is the invention according to claim 8.
According to the showcase management device according to the above, when the refrigerator is provided with a fan for cooling the condenser and a motor for driving the fan, the notification means, the pressure fluctuation amount Further, as a failure factor when the ratio is the largest, at least one of abnormality of the motor and influence of wind of the fan is also notified.

According to a tenth aspect of the present invention, there is provided a showcase management apparatus according to the fifth aspect, wherein the failure estimating means is configured to determine a fluctuation amount (hereinafter referred to as a fluctuation amount) of the pressure on a discharge side of the refrigerator every predetermined period. “Pressure fluctuation amount”) and the time required to lower the temperature of the cool air to a predetermined temperature under a predetermined specific situation (hereinafter referred to as “reduction time”),
Fluctuation amount for each predetermined period (hereinafter "reduction time fluctuation amount")
And a difference (hereinafter, referred to as a "time difference fluctuation amount") of a difference (hereinafter, referred to as "time difference") between a time required for lowering the internal temperature to a predetermined temperature and the lowering time in the specific situation (hereinafter, referred to as a "time difference"). )), The fluctuation amount calculating means for obtaining the pressure fluctuation amount, the reduction time fluctuation amount and the time difference fluctuation amount, and the fluctuation amount at a predetermined time as a reference value, The ratio between the value and the variation obtained during the period to be subjected to the failure estimation is calculated for each of the three items, by the variation ratio calculating means to be determined, and by the variation ratio calculating means to calculate the ratio A cumulative value calculating means for calculating the cumulative value of the values for each of the three items, and a cumulative value for determining the relative magnitude relationship between the cumulative values of the three items obtained by the cumulative value calculating means. Value determining means, and the notifying means notifies a failure factor associated with the item having the largest cumulative value as a result of the determination by the cumulative value determining means. It is characterized by.

The invention according to claim 11 relates to the showcase management apparatus according to claim 10, wherein the notifying means stores related information defining a correspondence between the three items and a cause of failure. By referring to the related information based on the result of the determination by the cumulative value determining means, a failure factor associated with the item having the largest cumulative value is obtained, and the content thereof is obtained. It is characterized by being notified.

According to a twelfth aspect of the present invention, there is provided a showcase management apparatus according to the eleventh aspect, wherein the notifying means determines that the cumulative value of the pressure variation is the largest when the accumulated value is the largest. Clogging of the condenser, and irradiation of direct sunlight, and at least one of the following, when the cumulative value of the amount of fluctuation in the reduction time is the largest, the refrigerant as a failure factor, And at least one of clogging of the condenser and clogging of the blower port is reported. When the cumulative value of the time difference fluctuation amount is the largest, at least one of the clogging of the blower port and the turbulence of the cool air blow is reported as a failure factor. And it features.

According to a thirteenth aspect of the present invention, there is provided the showcase management apparatus according to the twelfth aspect, wherein the refrigerator includes a fan for cooling the condenser and a motor for driving the fan. In this case, the notifying means further notifies at least one of an abnormality of the motor and an effect of wind of the fan as a failure factor when the cumulative value of the pressure fluctuation amount is the largest. It is characterized by that.

According to a fourteenth aspect of the present invention, there is provided the showcase management apparatus according to any one of the sixth to thirteenth aspects, wherein the fluctuation amount calculating means includes a pressure on the discharge side, the reduction time, For each of the time differences, a representative value in the period is obtained for each predetermined period, a difference between the representative values for each period is obtained, and this difference is used as the variation.

The invention according to claim 15 relates to the showcase management apparatus according to claim 14, wherein the representative value is an average value or a maximum value in the period.

According to a sixteenth aspect of the present invention, there is provided the showcase management device according to any one of the sixth to fifteenth aspects, wherein the failure estimating means supplies the refrigerant to the evaporator. Percentage of time spent (hereinafter referred to as “driving rate”)
And a condition that the operation rate calculated by the operation rate calculation means is equal to or higher than a predetermined reference operation rate (hereinafter referred to as “condition A”), and a temperature of the cool air is a predetermined temperature. A condition (hereinafter, referred to as “condition B”) that the above state continues for a predetermined time or more, and a condition determining unit that determines whether both the condition A and the condition B are satisfied. And the notification unit notifies the failure factor corresponding to the item only when both the condition A and the condition B are satisfied as a result of the determination by the condition determination unit. It is characterized by the following.

According to a seventeenth aspect of the present invention, there is provided the showcase management apparatus according to the sixteenth aspect, wherein the condition determining means further includes the internal temperature being equal to or higher than a predetermined temperature. A condition (hereinafter referred to as "condition C") that the state has continued for a predetermined time or more, and it is determined whether or not the condition C is satisfied; As a result of the determination by the means, when at least one of the condition A and the condition B is not satisfied and the condition C is satisfied, it is determined that the temperature around the showcase is high as a failure factor. It is characterized by being notified.

According to the eighteenth aspect of the present invention,
A refrigerator that includes a compressor and a condenser, compresses the refrigerant by the compressor, and liquefies the refrigerant by radiating heat of the compressed refrigerant by the condenser; and a refrigerant supplied from the refrigerator. The heat exchange is performed in the evaporator to generate cool air, and the cool air is blown out from an air blowing port to cool a storage case in which goods are displayed and a pressure on a discharge side of the refrigerator is detected. Pressure detecting means, a cool air temperature detecting means for detecting the temperature of the cool air, and an in-chamber temperature detecting means for detecting a temperature in the housing,
The detection result of said pressure detection means, said cool air temperature detection means, and said internal temperature detection means is input.
7. A showcase system, comprising: the showcase management device according to any one of 7.

According to the invention of claim 19,
A function of providing a compressor, liquefying the refrigerant by the compressor, and performing a protection operation of changing its operation state to protect itself when the pressure value on the discharge side is equal to or higher than a predetermined threshold value. In a showcase management device that manages a refrigerator equipped with, and a showcase cooled by using a refrigerant supplied from the refrigerator, data indicating a pressure on a discharge side of the refrigerator is input, and There is provided a showcase management device including a refrigerator abnormality detection and notification means for detecting and reporting abnormality of the refrigerator.

[0027] According to a twentieth aspect of the present invention, there is provided a showcase management apparatus according to the nineteenth aspect, wherein the refrigerator abnormality detection informing means determines whether or not the pressure value on the discharge side of the refrigerator is the protection operation. Whether or not the threshold value to be started is exceeded is determined based on the input data.As a result of the determination by the pressure determination unit, if the threshold value is exceeded, a message to that effect is given. And a pressure abnormality notifying means for notifying.

According to the twenty-first aspect of the present invention,
A refrigeration unit that includes a compressor, liquefies the refrigerant by the compressor, and performs a protection operation that changes its operation state to protect itself when the pressure value on the discharge side is equal to or higher than a predetermined threshold value. Chiller, a showcase in which a storage cabinet in which goods are displayed and displayed using the refrigerant supplied from the refrigerator, is cooled, pressure detection means for detecting pressure on the discharge side of the refrigerator, and the pressure detection means 21. The showcase system according to claim 19, wherein the detection result is input.

Next, the operation will be described. First, the operation of the first to fourth aspects of the present invention will be described.
In the showcase, cold air is generated by causing the refrigerant supplied from the refrigerator to exchange heat with the evaporator. And
The cold storage cools the storage in which the products are displayed and stored.

In this state, the internal temperature detecting means detects the temperature of the storage (inside temperature). Based on the detection result, the frost detection means detects frost in the evaporator. This detection of frost may be performed, for example, by calculating the rate of change of the internal temperature, and determining that frost has occurred when the rate of change exceeds a predetermined range.
In this case, it is preferable that the rate of change be determined based on the temperature in the refrigerator at the beginning of the operation of the showcase. When frost formation is detected by the frost formation detection means, the frost formation notification means reports occurrence of frost formation.

Next, the operation of the inventions of claims 5 to 9 and the inventions of claims 14 to 18 which are dependent on them will be described together. The pressure detecting means detects the discharge side pressure of the compressor, the cold air temperature detecting means detects the temperature of the cold air, and the internal temperature detecting means detects the internal temperature of the refrigerator. Then, these detection results (that is, data indicating the pressure on the discharge side of the refrigerator, the temperature of the cool air blown to the showcase, and the temperature in the refrigerator) are input to the failure estimating means.

The failure estimating means and the notifying means estimate the occurrence of a failure based on the input data, and notify the estimation result. The failure estimating means and the notifying means can be more specifically configured as follows. That is, the fluctuation amount calculating means obtains three items (pressure fluctuation amount, reduction time fluctuation amount, and time difference fluctuation amount). For example, for each of the pressure on the discharge side, the reduction time, and the time difference, a representative value (for example, an average value or a maximum value) in the predetermined period is determined. Then, by obtaining the difference between the representative values for each period, the value of each item (that is, the amount of fluctuation) is obtained.

Subsequently, the variation ratio calculating means determines the ratio between the reference value and the variation determined during the period for which the failure is estimated for each of the three items. The reference value is a fluctuation amount at a predetermined time. The ratio determination means determines the relative magnitude relationship between the values of the ratios for each of the three items.

The notifying means notifies the failure factor associated with the item having the largest ratio value as a result of this determination. For example, if the ratio for pressure fluctuation is the largest,
As the failure factors, clogging of the condenser, irradiation of direct sunlight, influence of wind of a fan for cooling the condenser, abnormality of a motor for driving the fan, and the like are reported. If the ratio for the amount of fluctuation in the downtime is the largest, the causes of failure include insufficient refrigerant, turbulence in cooling air, too high temperatures around the showcase, clogging of the condenser, and Notify clogging and the like. When the ratio for the time difference fluctuation amount is the largest, the clogging of the air outlet and the turbulence of the cool air are notified as the failure factors. In addition, this notification obtains the failure factor associated with the item having the largest ratio value by referring to the related information that defines the correspondence between the three items and the failure factor, for example. May be notified.

The following structure may be further provided. The condition determining means determines that the condition A (the operation rate is equal to or higher than the predetermined reference operation rate) and the condition B (the state in which the temperature of the cold air is equal to or higher than the predetermined temperature continues for a predetermined time or longer). Is determined to be true or not. Further, it is determined whether or not a condition C (a state in which the internal temperature is equal to or higher than a predetermined temperature has continued for a predetermined time or longer) is satisfied. The driving rate is determined by the driving rate calculating means. Only when both the condition A and the condition B are satisfied as a result of the determination, the notifying unit notifies the failure factor corresponding to the above-described item. On the other hand, when at least one of the condition A and the condition B is not satisfied and the condition C is satisfied, it is notified that the temperature around the showcase is high as a failure factor.

Next, the operation of the fifth, tenth, thirteenth, and thirteenth dependent aspects of the invention will be summarized. The pressure detecting means is the discharge side pressure of the compressor, the cold air temperature detecting means is the temperature of the cold air,
The inside temperature detection means detects the inside temperature. And
These detection results (ie, the pressure on the discharge side of the refrigerator,
Data indicating the temperature of the cool air blown into the showcase and the temperature in the refrigerator) are input to the failure estimating means.

The failure estimating means and the notifying means estimate the occurrence of a failure based on the input data, and notify the estimation result. The failure estimating means and the notifying means can be more specifically configured as follows. That is, the fluctuation amount calculating means obtains three items (pressure fluctuation amount, reduction time fluctuation amount, and time difference fluctuation amount). For example, for each of the pressure on the discharge side, the reduction time, and the time difference, a representative value (for example, an average value or a maximum value) in the predetermined period is determined. Then, by obtaining the difference between the representative values for each period, the value of each item (that is, the amount of fluctuation) is obtained.

Subsequently, the fluctuation ratio calculating means obtains the ratio between the reference value and the fluctuation obtained during the period for which the failure is estimated for each of the three items. The reference value is a fluctuation amount at a predetermined time. The cumulative value calculating means calculates, for each of the three items, the cumulative value of the ratio value obtained by the variation amount calculating means. Then, the cumulative value determining means determines a relative magnitude relationship between the cumulative values of the three items.

The notifying means notifies the failure factor associated with the item having the largest cumulative value as a result of this determination. For example, when the cumulative value of the pressure fluctuation amount is the largest, as failure factors, clogging of the condenser, irradiation of direct sunlight, influence of a wind of a fan for cooling the condenser, and a motor for driving the fan To inform of abnormalities. If the cumulative value of the reduction time variation is the largest,
As the failure factors, the shortage of the refrigerant, the turbulence of the cooling air, the excessive temperature around the showcase, the clogging of the condenser, and the clogging of the air outlet are reported. If the cumulative value of the time difference fluctuation amount is the largest, the clogging of the air outlet and the turbulence of the cool air are notified as the failure factors. Note that this notification is made by, for example, referring to related information that defines the correspondence between the three items and the failure factors.
The failure factor associated with the item having the largest accumulated value may be acquired and its content may be reported.

The following structure may be further provided. The condition determining means determines that the condition A (the operation rate is equal to or higher than the predetermined reference operation rate) and the condition B (the state in which the temperature of the cold air is equal to or higher than the predetermined temperature continues for a predetermined time or longer). Is determined to be true or not. Further, it is determined whether or not a condition C (a state in which the internal temperature is equal to or higher than a predetermined temperature has continued for a predetermined time or longer) is satisfied. The driving rate is determined by the driving rate calculating means.

Only when both the condition A and the condition B are satisfied as a result of the determination, the notifying means notifies the failure factor corresponding to the above-mentioned item. On the other hand, when at least one of the condition A and the condition B is not satisfied and the condition C is satisfied, it is notified that the temperature around the showcase is high as a failure factor.

Next, the operation of the present invention will be described. The pressure detecting means detects the pressure on the discharge side of the refrigerator, and inputs the detection result to the refrigerator abnormality detection notifying means. The pressure determination means of the refrigerator abnormality detection and notification means determines whether or not the pressure value on the discharge side of the refrigerator exceeds a threshold value at which the protection operation is started based on the input data. If the result of this determination is that the threshold value has been exceeded, the pressure abnormality notification means notifies that fact.

[0043]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiments of a showcase management apparatus and a showcase system according to the present invention will be described below in detail with reference to the accompanying drawings.

(Embodiment 1) In the showcase system of this embodiment, for each of the three items (discharge-side (high-pressure side) pressure, pull-down time, and difference in pull-down time) to be described later, the operation starts relatively. The reference data is created based on the data obtained in the initial stage, and the data to be determined is created for each item on a daily basis.
Further, a ratio between the reference data and the data to be determined is obtained for each item. Then, the failure factor is determined based on the relative magnitude relation of the ratio for each item. The details will be described below.

First, the overall configuration of the showcase system of this embodiment will be described with reference to FIG. This showcase system comprises an open showcase 1 and a refrigerator 5
And the control device 30. On the main body 2 of the open showcase 1, a display shelf 3 for placing goods is provided on the front side thereof. The front side of the display shelf 3 is in an open state (opening 4) for putting in and taking out goods. In order to maintain the inside of the refrigerator 11 at a desired temperature, a flow (air curtain) of cool air is formed in the opening 4 from the upper end (the outlet 10) to the lower end (the inlet 12). Thereby, the whole inside 11 of the refrigerator is cooled.

On the other hand, from the lower part to the back part and the upper part of the main body 2, an air flow path of an inlet 12, a blower 8, a duct 9 and an outlet 10 is formed.
Further, the duct 9 is provided with an evaporator 7 for exchanging heat with the refrigerant supplied from the refrigerator 5. The air taken in from the suction port 12 by the blower 8 is cooled around the evaporator 7. Thereafter, the cooled air (cold air) blows out from the blowout port 10 to form the above-described air curtain. A part of the cool air blown out from the outlet 10 is taken in again from the inlet 12 and circulated.

The open showcase 1 includes a plurality of temperature sensors (outside air temperature thermistor 19,
Internal temperature thermistor 20, Temperature controlled thermistor 2
1. A defrost temperature thermistor 22) is provided. The outside temperature thermistor 19 detects the temperature around the open showcase 1 and is provided at the upper end of the opening 4. The in-compartment temperature thermistor 20 is for detecting the temperature of the in-compartment 11, and is provided on the ceiling surface of the in-compartment 11. Temperature control thermistor 21
Is for detecting the temperature of air (cold air) cooled by being guided to the duct 9 by the blower 8.
At the top. Defrosting temperature thermistor 22
Is for detecting the temperature near the evaporator 7,
It is provided in the duct 9 near the evaporator 7.
The detection results of these various sensors are transmitted to a control device 30 described later.
Is output to.

Although not shown in the figure, an electromagnetic valve for turning on / off the flow of the liquid refrigerant from the refrigerator 5 to the evaporator 7 is provided. Further, a heater is used for removing frost attached to the evaporator 7 (defrosting operation). In addition. In the defrosting operation, specifically, the supply of the liquid refrigerant to the evaporator 7 is stopped by turning off the electromagnetic valve, and the frost adhering to the evaporator 7 is melted by energizing the heater. Done in These are the control devices 3
On / off or energization is performed based on an instruction from 0.

Next, the structure of the refrigerator 5 will be described. The refrigerator 5 is connected to the evaporator 7 of the main body 2 through a refrigerant pipe 6, and circulates a refrigerant between the two through the refrigerant pipe 6 to supply cold heat to the main body 2. That is, the low-temperature and low-pressure gas refrigerant sent from the evaporator 7 is sent to the compressor 13 through the refrigerant pipe 6. Then, by being compressed here, it becomes a high-temperature and high-pressure gas refrigerant. After this, the gas refrigerant in this high temperature and high pressure state
By radiating heat in the condenser 14, the liquid refrigerant becomes a high-temperature and high-pressure liquid refrigerant. Then, this liquid refrigerant is sent to the evaporator 7 again through the refrigerant pipe 6. On the way, this refrigerant
It becomes low-temperature and low-pressure liquid refrigerant by an expansion valve provided in the open showcase. In addition, the compressor 13 is inverter-controlled by a refrigeration control circuit described later, and is configured to be able to change its operation frequency (that is, capacity) as necessary. Further, the refrigerator 5 includes a motor and a fan driven by the motor as a mechanism for cooling the condenser 14.

The refrigerator 5 of this embodiment has a control circuit (refrigerator control circuit 50) of the refrigerator 5 itself, separately from a control device 30 described later. The refrigerator control circuit 50 has a normal mode and a protection mode as its operation modes. In the normal mode, the compressor 13 and the like are controlled (normal operation control) according to an instruction from the control device 30. However, if the load is expected to exceed the allowable range of the refrigeration cycle equipment and the electric / electronic components due to an increase in load and transient disturbance, the refrigerator control circuit 50 switches its operation mode to the protection mode at its own discretion. Is configured. In this protection mode, in order to avoid a failure, the refrigerator control circuit 50 determines at its own discretion the refrigerator 5
(Protection control). For example, when the discharge (high pressure) side pressure is too high, the operation frequency is reduced.

The refrigerator 5 is provided with various sensors 15, 16, 17, and 18 for monitoring the operation state. The suction (low pressure) side temperature sensor 15 is for measuring the temperature of the refrigerant gas before entering the compressor 13. The suction (low pressure) side pressure sensor 16 is for measuring the pressure of the refrigerant gas before entering the compressor 13.
The discharge (high pressure) side temperature sensor 17 is for measuring the temperature of the refrigerant after compression by the compressor 13. The discharge (high pressure) side pressure sensor 18 is for measuring the pressure of the refrigerant after compression by the compressor 13. The detection results of these various sensors are output to the control device 30 described later.

Next, the control device 30 will be described with reference to FIG. The control device 30 is for controlling and controlling the entire showcase system. The control device 30 includes the above-described various temperature sensors 15, 17, 1
9, 20, 21, 22 and various pressure sensors 1
The detection results are input from 6,18. The control device 30 is configured to perform various controls, determinations, and the like using these detection results, data prepared in advance, and the like.
The sensors 15, 16, 17, 18, 19, 20, 2
1, 22, the compressor 13 and the like are as described above.

The control device 30 is, specifically, a CPU
31, a ROM 32, a RAM 33, and an alarm 35. The alarm 35 is for notifying the administrator of the occurrence of a failure, and in this embodiment,
It is configured to include a liquid crystal display device, a lamp, a buzzer, and the like. The annunciator 35 is configured to operate in accordance with an instruction from the CPU 31. For example, CPU
In accordance with an instruction from 31, a message indicating the result of the failure determination (that is, a possible failure factor) can be displayed on the liquid crystal display device. The CPU 31 has a ROM 3
By executing the various control programs stored in 2,
Various functions are realized. For example, this embodiment has a function of performing a failure determination.

In particular, in the failure determination according to the present embodiment, only the detection results of the discharge (high pressure) side pressure sensor 18, the internal temperature thermistor 20, and the temperature control thermistor 21 among the detection results of the various sensors described above. Is configured to be used. The control device 30 itself is configured to calculate reference data serving as a reference for determination, determination target data serving as a determination target, and various coefficients (a condenser coefficient, a honeycomb coefficient, and a refrigerant coefficient). Details of these reference data, determination target data, and the like will be described later in the operation description.

Various other information necessary for this determination and the like are stored in the ROM 32 and the RAM 33. As the data held in the ROM 32, for example, threshold values A, B, C, D, E, and F described later are raised. Also, information (related information) in which the failure factors are associated with coefficients (condenser coefficient, honeycomb coefficient, refrigerant coefficient) to be described later is stored. The data stored in the RAM 33 includes detection results of various sensors, reference data, data to be determined, and the like.

The "frost formation detecting means" and the "frost formation notification means" in the claims are realized by the control device 30 in this embodiment. "Blow port"
Corresponds to the outlet (honeycomb part) 10. The “failure estimation unit” and the “notification unit” are realized by the control device 30. The “variation amount calculating means”, “variation amount ratio calculating means”, and “ratio determining means” are realized by the control device 30. The “ratio of the amount of change” corresponds to a ratio between reference data described later and data to be determined. The “reduction time” corresponds to a pull-down time of the temperature adjustment temperature. The “time difference” corresponds to a difference between the pull-down time of the temperature adjustment temperature and the pull-down time of the internal temperature. The “pressure detecting means” is realized by the discharge (high pressure) side pressure sensor 18 and the like. The “cool air temperature detecting means” is realized by the temperature controlled thermistor 21 and the like. The “inside temperature detecting means” is realized by the inside temperature thermistor 20 or the like. The “refrigerator abnormality detection notification means” includes the control device 3
0. The “pressure determination unit” and the “abnormality notification unit” are realized by the control device 30. “Specific situation” is immediately after the defrosting operation. However, since the above-described units function in close cooperation with each other, the correspondence described here is not strict.

Next, the operation of the failure judgment in this embodiment will be described. In this showcase system, 3
Different types of failure determination processing (FIGS. 3, 4, and 5) are performed. These three failure determination processes can be independently executed, and are not mutually exclusive. Even in an actual control program, these failure determination processes are integrated into one. However, for the sake of simplicity, the description will be made separately for each failure determination process.

Further, each of these failure determination processes is determined based on the relationship between the content of the failure and the characteristics of the signal change of each sensor. The relationship between the content of this failure and the characteristics of signal changes of various sensors, which is the premise of this failure determination, will be described later with reference to FIGS.

(1) Diagnosis of frost formation failure A failure determination process for diagnosing the presence or absence of frost on the evaporator 7 will be described with reference to FIG. The main body 2 of the open showcase 1 and the refrigerator 5 are installed, and the power is turned on. Then, the control device 30 starts control and determination of each unit. The refrigerator 5 starts operating, and starts cooling the inside of the refrigerator 11. When the inside 11 is sufficiently cooled and the state is stabilized, the control device 30 detects the inside temperature based on the detection result of the inside temperature thermistor 20. Then, the detected value is stored in the RAM 33 so as to be used as reference data in the subsequent determination processing (step S132).

Regarding the timing of collecting the reference data, in practice, it is considered that the state of the interior 11 is stabilized when a predetermined time has elapsed after the power is turned on.
The temperature inside the refrigerator may be detected. After this, the control device 30 detects the internal temperature every predetermined time (steps S134 and S136). Then, the change rate of the inside temperature is calculated by comparing the inside temperature detected at that time with the reference data (the inside temperature detected in step S132) (step S138).

Subsequently, the control device 30 compares the rate of change of the inside temperature obtained at this time with the threshold value A (step S1).
40). As a result of this comparison, when the rate of change of the internal temperature is equal to or higher than the threshold value A, it is determined that frost formation of a certain level or higher has occurred in the evaporator 7. In this case, the control device 30 proceeds to step S142. In step S142, the control device 30 activates the alarm 35 to start issuing a "frost alarm". Thereafter, control device 30 returns to step S134 and repeats the same operation. If it is smaller than the threshold value A in step S140, that is, if there is no abnormality, step S134 is left as it is.
Return to

While the power is on, the control device 30 keeps executing this determination processing. Note that the temperature inside the refrigerator may temporarily rise due to replenishment of new products or fluctuations in the surrounding air. As shown in FIG. 3, if the presence or absence of frost is simply determined based on the change rate of the internal temperature at a certain timing, an erroneous determination may occur.
In order to avoid such an erroneous determination, in addition to the above-described determination condition (step S134: whether or not the rate of change in the internal temperature is equal to or higher than the threshold A), "the temperature has not dropped for a certain time or longer" May be added to the determination condition.

Immediately after the installation of the showcase 1 and the refrigerator 5, an initial failure may occur. For this reason, the reference data may be collected after a certain period sufficient to determine whether or not an initial failure has occurred after the start of operation (power-on).

(2) Diagnosis of Clogging Failure and the Like A failure determination process for diagnosing clogging of the condenser 14 and abnormality of the blower 8 will be described with reference to FIG. The main body 2 and the refrigerator 5 of the open showcase 1 are installed, the power is turned on, and the operation starts. Then, the control device 30 starts control and determination of each unit. The refrigerator 5 starts operating, and starts cooling the inside of the refrigerator 11.

On the operation start date (Month / Month), the control unit 30
Obtains various data based on signals from various sensors and stores them in the RAM 33 (step S162).
These data are specifically obtained as follows. That is, when the inside of the refrigerator 11 is sufficiently cooled and the state is stabilized, the control device 30 detects various data based on signals from various sensors. Here, the detection result of the internal temperature thermistor 20 (inside temperature), the detection result of the controlled temperature thermistor 21 (controlled temperature), and the detection result of the discharge (high pressure) side pressure sensor 18 (discharge of the refrigerator) (High pressure) side pressure). Then, the captured data is sequentially stored in the RAM 33.

At the end (or a predetermined time) of the operation start date (Month / Month), the average value of each of the data taken in on that day (operation start date) is obtained, so that Ask. Discharge (high pressure) side pressure P of the refrigerator The pull-down time Ta of the regulated temperature The difference Tb between the pull-down time between the inside temperature and the regulated temperature Note that the “pull-down time” means that the temperature that has risen during the defrosting operation is increased again. This is the time required to return to the normal temperature (set temperature) (see FIG. 16).

These data (P, Ta, Tb) will be obtained every day thereafter. However, if it is necessary to distinguish the day when these data were obtained, the number of days from the operation start date (operation (The start date is 1). For example, the data on the operation start date is P1,
Ta1 and Tb1. The control device 30 holds the data (P1, Ta1, Tb1) thus obtained in the RAM 33 so as to be used for the subsequent determination processing.

On the second day of operation (1 month m + 1 day), the control device 3
0 calculates the data (P2, Ta2, Tb2) for the second day in the same manner as the operation start date, and stores it in the RAM.
33 (step S164). Subsequently, after that, the control device 30 stores the data (P1, Ta1, Tb1) regarding the operation start date (Month m) and the second operation day (L1).
Data (P2, Ta2, Tb) for month m + 1
2), data (reference data) serving as a reference for failure determination is calculated (step S166). here,
This reference data is obtained by calculating the difference between the data on the operation start date and the data on the second day of operation. That is, the reference data is ΔP (= P1−P2), ΔTa (=
Ta1−Ta2) and ΔTb (= Tb1−Tb2). In order to clearly distinguish the reference data from the data to be determined, which will be described later, a suffix “s” is added to the reference data and described as ΔPs, ΔTas, and ΔTbs.

After the third day of operation, the processing of steps S168 to S184 described below is repeated every day. Here, the third day of operation (1 month + 2 days)
Will be described as an example. However,
Steps S168 and S170 in FIG. 4 are described as being on the nth day of operation.

The control device 30 obtains data (P3, Ta3, Tb3) in the same manner as before (step S16).
8). Then, data to be subjected to failure determination (determination target data) is obtained. This determination target data is obtained in the same manner as the reference data. That is, the data (P3, Ta3, Tb3) obtained on this day and the data (P
2, Ta2, Tb2).

The data to be determined (ΔP, ΔTa,
ΔTb) will be obtained every day thereafter. When it is necessary to distinguish the days when these data were obtained, the number of days from the operation start date (the operation start date is set to 1) is added. For example, the data to be determined for the third day of operation (difference between the third day and the second day) is ΔP3, ΔT
a3 and ΔTb3.

Next, the control device 30 sets the following conditions a,
It is determined whether both of b are satisfied (step S172). Condition a: The operation rate is 100% or a high value close thereto. Condition b: Temperature control temperature at that time (temperature control temperature thermistor 2
(The detected temperature of 1) is equal to or higher than the value obtained by adding the threshold value B to the set value at that time, and continues for the threshold time C or more.

Here, the “operating rate” refers to the time during which the solenoid valve for controlling the flow of the liquid refrigerant from the refrigerator 5 to the evaporator 7 is ON (that is, the refrigerant is not supplied to the evaporator 7). This is the ratio of the supplied time to the operating time (however, the defrosting operation time is removed). This operation rate is also calculated by the control device 30. If the result of determination in step S172 is that both of these conditions a and b are satisfied, it is determined that some sort of failure has occurred. In this case, the process proceeds to step S174.

At step S174, control unit 30
Calculates the ratio between the reference data (ΔPs, ΔTas, ΔTbs) and the data to be determined on this day (ΔP3, ΔTa3, ΔTb3) in order to determine the details of the failure. Then, the calculation result is calculated by using the condenser coefficient (= ΔP3 /
ΔPs), the refrigerant coefficient (= ΔTa3 / ΔTas) and the honeycomb coefficient (= ΔTb3 / ΔTbs). Here, the ratio is obtained in order to make these numerical values dimensionless. Also, it is for normalization based on the reference data. By performing this processing, as described later, these can be compared with each other to determine the relative magnitude relation.

In the following step S176, control device 30 diagnoses a failure factor based on the relative magnitude relation between the condenser coefficient, the refrigerant coefficient, and the honeycomb coefficient thus obtained. This is because these coefficients (ie ratios)
This is because the larger the value is, the more remarkable the fluctuation of the sensor signal is, and it is considered that the possibility of a failure factor related to the sensor signal is large. Then, the control device 30 activates the annunciator 35 to transmit an alarm according to the diagnosis result.

In the control device 30 according to the present embodiment, the cause of the failure and the magnitude relation among the coefficients (condenser coefficient, honeycomb coefficient, refrigerant coefficient) are defined as follows.

When the condenser coefficient (= ΔPn / ΔPs, where n is the number of days from the start of operation) is the largest, failure factors such as clogging of the condenser 14, abnormality of the blower 8 of the condenser 14, and wind of the blower 8 are considered as failure factors. A decrease in the heat exchange performance of the condenser 14 due to a shortcut, irradiation of direct sunlight, or the like is defined.

The honeycomb coefficient (= ΔTbn / ΔTbs, n
Is the largest number of days since the start of operation), clogging of the honeycomb 10 and disturbance of the air curtain are defined as failure factors.

When the refrigerant coefficient (= ΔTan / ΔTas, n is the number of days from the start of operation) is the largest, the causes of failure include refrigerant gas leakage, air curtain turbulence, high store temperature, condenser 14 clogging, and honeycomb. Ten clogging and the like are defined. In this case, the reason why the clogging of the condenser 14 and the clogging of the honeycomb 10 are raised is as follows. That is, the tendency of the rise of the discharge (high pressure) side pressure of the refrigerator, which occurs when the condenser 14 is clogged, becomes difficult to occur due to the influence of the refrigerant gas leakage. High pressure) side pressure drops). Similarly, the difference (T) between the pull-down time of the internal temperature and the regulated temperature that occurs when the honeycomb 10 is clogged.
This is because b) is difficult to spread due to the influence of refrigerant gas leakage. As described above, the clogging of the condenser 14 itself can be detected based on the condenser coefficient. Further, the clogging itself of the honeycomb 10 can be detected based on the honeycomb coefficient.

By the way, as a result of the determination in step S172, if both of the above conditions a and b are not simultaneously satisfied (if at least one of them is not satisfied), the process proceeds to step S180.

At step S180, control device 30
Determines whether or not the following condition c is satisfied. Condition c: The state in which the internal temperature is equal to or higher than the value obtained by adding the threshold D to the temperature control set value is continuous for the threshold time E or longer.

If the condition c has been satisfied, the control device 30 activates the alarm 35 to send an alarm indicating that the temperature inside the store is high (the temperature around the showcase is high) (step S182). . Step S176, 182
After that, if the condition c is not satisfied in step S180, the date is updated so as to be shifted by one day (step S184), and the process returns to step S168. In other words, after the third day of operation (1 month + 2 days),
As described above, the processing from step S168 to step S184 is repeatedly executed while updating the determination target data and the like every day.

(3) Diagnosis of abnormality of refrigerator 5 A failure determination process for diagnosing abnormality of the discharge (high pressure) side pressure of the refrigerator 5 will be described with reference to FIG. The control device 30 always repeats the following processing during the operation of the refrigerator 5.

First, the control device 30 reads the detection result of the discharge (high pressure) side pressure sensor 18 (step S20).
2). Then, the detection result read at that time, that is,
It is determined whether or not the pressure value of the discharge (high pressure) side pressure of the refrigerator 5 is equal to or more than the pressure value (threshold F) at which the refrigerator 5 enters the protection control operation (step S204). As a result of the determination, the threshold value F
If this is the case, the alarm 35 is activated to issue a "high-pressure cut advance warning" (step S206).

The reason why such an alarm is issued is that when the refrigerator 5 shifts to the protection mode, it is considered that the commodity may be damaged. That is, the refrigerator 5 shifts to the protection mode by its own judgment (control by the refrigerator control circuit 50), thereby avoiding the failure of the refrigerator 5 itself. However, in this protection mode, since the operating frequency is reduced, the internal temperature may increase. As a result, the product may be damaged.

The abnormal rise of the discharge (high pressure) side pressure is as follows.
It often occurs due to the progress of a failure such as clogging of the condenser 14. This is because when such a failure occurs, even if the temperature in the refrigerator is temporarily maintained at a certain level, it may eventually lead to a failure that does not cool down.

As described above, according to this embodiment, the occurrence of a failure can be estimated in advance. Therefore, the cause of the failure can be dealt with by the user or the serviceman. Therefore, it is possible to eliminate a loss of a sales opportunity due to a failure. In addition, since the location of the failure is known in advance, tools, equipment,
This will help you understand what to prepare, leading to more efficient maintenance work.

Further, since erroneous detection due to a temporary rise in the temperature of the showcase compartment due to product replenishment can be prevented, wasteful work of service personnel can be reduced, leading to more efficient maintenance work. In addition, since there is no need to construct a huge database, operation is easy. Also, the device can be simplified.

In this embodiment, the reference data is calculated based on the difference between the data on the first and second days of operation. In addition, the data to be judged, which is the material for daily judgment,
The calculation was based on the data of the day and the data of the previous day. However, the sampling period of these data may be set longer to increase the accuracy of the determination. For example, in order to increase the accuracy of the reference data, the reference data may be calculated based on data obtained during a period of one week or more from the operation start date. In the configuration in which the sampling period of the data used for the determination is lengthened, the influence of the variation due to the use environment and the like is reduced, and the accuracy of the failure prediction is high.

In the present embodiment, the reference data is calculated based on the data immediately after the installation of the showcase 1 and the refrigerator 5 (the first and second days from the operation start date). But,
Immediately after the installation of the showcase 1 and the refrigerator 5, an initial failure may occur. Therefore, the reference data may be constructed based on data obtained after a certain period of time has elapsed after the start of operation. In such a configuration, the influence of the initial failure is eliminated, and more accurate failure determination is possible.

In this embodiment, the average value of the data obtained on that day is used as the representative value for that day for calculating the reference data and the data to be determined. However, the maximum value of the data obtained on that day may be used as the representative value. Failure determination more sensitive to data fluctuations is possible.

In this embodiment, the failure determination is performed by the control device 30 that controls the entire system. However, the functional part for performing the failure determination is provided by the control device 3
It is also possible to configure separately from 0.

Although not particularly described in the above description, the showcase 1 and the refrigerator 5 and the control device 30
(Or a functional part that is provided independently of the control device 30 and performs a failure determination) may be connected in any form. For example, they may be connected via a network.

(Embodiment 2) In this embodiment 2,
The failure determination processing for a clogging failure or the like (FIG. 6) is different from the failure determination processing for a clogging failure or the like (FIG. 4) in the first embodiment. In Embodiment 1 described above, the ratio between the determination target data and the reference data obtained on that day is directly used as the coefficient (condenser coefficient, refrigerant coefficient, honeycomb coefficient) for that day (see step S174 in FIG. 4). On the other hand, in the second embodiment, the above-described coefficients (condenser coefficient, refrigerant coefficient, etc.) are accumulated, and the magnitude relation of the accumulated values is determined, so that the diagnosis is performed based on the operating condition for a longer period. Is made. Other points are the same as the first embodiment. Therefore, in the following description, only the difference from the first embodiment, that is, the content of the failure determination processing will be described.

A process for determining a failure such as a clogging failure in the second embodiment will be described with reference to FIG. In the process of FIG. 6, various coefficients (condenser coefficient,
A process (Step S190) for initializing (= 0) the refrigerant coefficient and the honeycomb coefficient) is newly added. The process of step S190 is performed only once at the start of operation.

Further, in the processing of FIG. 6, step S of FIG.
The processing of step S195 is provided instead of the processing of 174. In this step S195, the ratio between the determination target data and the reference data obtained on that day (for example, for the nth day from the start of operation, ΔPn / ΔPs, ΔTbn / Δ
Tbs, ΔTan / ΔTas) is added to the previous coefficient value to obtain a new coefficient value. That is, in this embodiment, various coefficients (condensation coefficient, refrigerant coefficient, honeycomb coefficient) on the nth day from the start of operation are defined as follows.

Condensation coefficient = Condensation coefficient + ΔPn / ΔPs Refrigerant coefficient = Refrigerant coefficient + ΔTan / ΔTas Honeycomb coefficient = Honeycomb coefficient + ΔTbn / ΔTbs

The processing in step S195 is different from step S174 in FIG.
The processing is executed in the former stage of 72, but this is almost the same regardless of which (the former stage or the latter stage) is performed.

Next, the meaning and validity of such accumulation will be described with reference to FIG. The information (the discharge side (high pressure) pressure, the pull-down time of the regulated temperature, the difference between the pull-down time between the inside temperature and the regulated temperature) that was the basis of the determination in the first embodiment is not limited to the fault. (Fig. 7)
(A)). For example, the temperature may fluctuate depending on the temperature around the open showcase 1 (in-store temperature), the temperature around the refrigerator 5 (outdoor temperature), the presence or absence of a night cover at night, and the lighting state of the fluorescent lamp illuminating the inside 11 of the refrigerator. There is.

However, the content of the fluctuation differs between the fluctuation caused by the failure and the fluctuation caused by the surrounding situation. In other words, as shown in FIG. 7B, the variation caused by the failure has a slight difference, but the width of the variation gradually increases in a certain direction. On the other hand, the fluctuation due to the surrounding situation is temporary. The direction also occurs in both positive and negative directions depending on the time. Eventually (or in the long run) it converges to a certain value (or within a range).

Therefore, by accumulating the above-mentioned coefficients and evaluating the accumulated value, it is possible to make a failure judgment while canceling out the temporary fluctuation caused by the surrounding situation. Become. That is, a highly accurate failure determination can be performed.

According to the second embodiment described above, the same effects as in the first embodiment can be obtained. Further, the influence of variations due to the use environment and the like can be reduced, and the accuracy of failure prediction can be further improved.

The “failure estimating means” and the “notifying means” in the claims are realized by the control device 30. The “cumulative value calculating means” and the “cumulative value determining means” are realized by the control device 30.
The “cumulative value” corresponds to the condensation coefficient, the refrigerant coefficient, and the honeycomb coefficient in this embodiment.

Finally, the phenomena that became the basis for determining the content of the failure determination in the first and second embodiments described above,
That is, characteristics of signal changes of various sensors when each failure occurs will be described. Here, (1) frost formation on the evaporator 7, (2) clogging failure of the condenser 14, (3) shortage of refrigerant gas, (4) change in pull-down time, (5) clogging of the honeycomb unit 10. , Will be described.

The “inside temperature” is a representative temperature of the inside 11. “Temperature-adjusted temperature” is the temperature of cold air at a predetermined location, and the temperature is adjusted based on this temperature-adjusted temperature.
In the showcase system of the above-described embodiment, the detection result of the internal temperature thermistor 20 is treated as the internal temperature here, and the detection result of the temperature controlled temperature thermistor 21 is treated as the temperature adjusted temperature here. ing.

(1) Behavior at the time of frost failure (ice bank) on the evaporator 7 The behavior at the time of frost failure (ice bank) on the evaporator 7 will be described with reference to FIGS. 8, 9 and 10. I do. FIG.
Shows the evaporator 7 from which the frost has been completely removed. FIG. 9 shows the evaporator 7 in a state where a limit amount of frost f that can completely remove frost by the defrosting operation is attached.

FIG. 10 shows that the frost adheres to the evaporator 7.
FIG. 3 is a diagram illustrating an influence on a detection value of each temperature sensor. At time t1 in FIG. 10, the evaporator 7 is in the state of FIG. At time t2, it is assumed that the state is as shown in FIG. As shown in FIG. 10, the outside temperature thermistor 19 measures the ambient temperature, and is not affected by the adhesion of frost f to the evaporator 7. Therefore, the detection value of the outside air temperature thermistor 19 is constant. On the other hand, with the attachment of the frost f to the evaporator 7, it becomes difficult for the cool air to flow through the duct 9. Therefore, the internal temperature thermistor 20 and the temperature control temperature thermistor 2
The detection value (inside temperature, controlled temperature) with 1 gradually increases.

(2) Behavior at the time of clogging failure of the condenser 14 The behavior at the time of clogging failure of the condenser 14 of the refrigerator 5 will be described with reference to FIG. 11, FIG. 12, FIG. 13 and FIG.
FIG. 11 shows the condenser 14 with the dust d completely removed.
FIG. FIG. 12 is a schematic diagram illustrating the condenser 14 in a state where the dust d is clogged. FIG. 13 is a diagram showing the relationship between the state of dust clogging in the condenser 14 and the detection result (temperature) of the discharge (high pressure) side temperature sensor 17. FIG. 14 is a diagram showing the relationship between the situation of dust clogging in the condenser 14 and the detection result (pressure) of the discharge (high pressure) side pressure sensor 18. Time t3 in FIGS. 13 and 14
Then, the condenser 14 is not clogged with dust (see FIG. 1).
1). On the other hand, it is assumed that the time t4 is a state where dust is clogged (FIG. 12).

When the condenser 14 is clogged, the heat transfer area becomes smaller. As a result, the heat radiation from the refrigerant gas is not performed normally, and the temperature and pressure of the refrigerant gas on the discharge (high pressure) side increase according to the level of clogging. Discharge (high pressure)
As the temperature and pressure of the refrigerant gas on the side increase, the temperature and pressure of the refrigerant guided to the evaporator 7 also increase. For this reason, the temperature of the interior 11 also increases. Furthermore, the refrigerant gas temperature and pressure on the suction (low pressure) side returning from the evaporator 7 to the refrigerator 5 also increase.

When the refrigerant gas pressure increases, the refrigerator 5 shifts to the protection mode. In this protection mode, since the operating frequency is reduced, the temperature and pressure of the refrigerant gas guided to the evaporator 7 further increase. As a result, the interior 11 is not cooled at all. If the clogging of the condenser 14 becomes more severe, the refrigerator 5 side also becomes abnormally high pressure and stops.

(3) Phenomenon when refrigerant gas is insufficient (leakage) Next, the phenomenon when refrigerant gas is insufficient is shown in FIGS.
6 will be described. FIG. 15 is a diagram showing the pressures on the suction (low pressure) side and the discharge (high pressure) side when the refrigerant gas is insufficient. Such a shortage of the refrigerant gas occurs due to reasons such as leakage of the refrigerant gas. In this figure, the horizontal axis is time. That is, FIG. 15 illustrates a state in which the leakage of the refrigerant gas continues as time elapses (that is, a state in which the shortage of the refrigerant gas increases as time elapses).

In the state where the refrigerant gas is insufficient, a small amount of the refrigerant gas is used until now (when the refrigerant gas is not insufficient).
Will receive the same amount of heat. That is, since heat exchange in the evaporator 7 proceeds excessively, the suction (low pressure) side pressure becomes higher than the normal state. The degree of the increase gradually increases in accordance with the degree of the shortage. On the other hand, the discharge (high pressure) side pressure tends to increase at a stage where the shortage of the refrigerant gas is small. This is because, as described above, the suction (low pressure) side pressure is increased due to the shortage of the refrigerant gas. However, when the shortage exceeds a certain level, the discharge (high pressure) side pressure, on the contrary,
Begins to drop. This is because the compression effect is reduced because the amount of the refrigerant gas itself is too small.

The same applies to not only the pressure but also the temperature (the suction (low pressure) side temperature and the discharge (high pressure) side temperature).

(4) Change in pull-down time FIG. 16 is a diagram showing the pull-down time of the inside temperature and the temperature control temperature after performing the defrosting operation. If frost forms on the evaporator 7, this frost is removed by performing a defrosting operation. However, this defrosting operation raises the internal temperature and the regulated temperature. In a state in which a sufficient amount of refrigerant gas is present, the evaporator 7 can sufficiently exhibit its cooling ability. Rapidly decreases to the normal temperature (set temperature). In other words, the time (pull-down time) required for the internal temperature and the regulated temperature, which have risen with the defrosting operation, to fall to the normal temperature (set temperature) is short. On the other hand, in a state where the refrigerant gas is insufficient, the cooling capacity in the evaporator 7 is reduced. , The time (pull-down time) required to decrease to becomes longer.

(5) Behavior at the time of clogging of the honeycomb portion 10 The outlet 10 (honeycomb portion) of the showcase is dusty.
FIGS. 17 and 18 show the behavior at the time of clogging with dust and the like.
This will be described with reference to FIG. FIG. 17 is a diagram showing the inside temperature and the temperature control temperature when dust and dust adhere to the outlet 10 (honeycomb portion). If there is no dust or dust attached to the outlet 10 (honeycomb portion), the temperature difference between the inside temperature and the temperature control temperature is about 5 ° C. However, if dust or dust adheres to the outlet 10 (honeycomb portion), the amount of air from the outlet 10 (honeycomb portion) decreases, so that cool air does not spread to the inside 11 and the inside temperature gradually increases. On the other hand, since the cool air reaches the inside of the duct 9 where the temperature control temperature thermistor 21 is installed,
The temperature control temperature is almost the same as before the attachment of dust and dust. Therefore, the temperature difference between the inside temperature and the temperature-control temperature gradually increases as compared to before the attachment of dust and dust. The above is the same even when considering not the temperature difference but the temperature ratio.

FIG. 18 is a diagram showing a change in the inside temperature and the temperature control temperature after the defrosting operation. In the state where there is no adhesion of dust and dust, the inside temperature and the temperature control temperature that have risen due to defrosting are rapidly increased to the normal temperature (set temperature) after the defrosting operation.
Down to However, in a state where dust and dirt are attached, the air volume from the outlet 10 (honeycomb portion) decreases. For this reason, the internal temperature pull-down time becomes long. On the other hand, the pulldown time of the temperature control temperature is
It is almost the same as the state without dust.

[0117]

As described above, according to the showcase management apparatus and the showcase system according to the present invention, a failure can be dealt with by a user or a service person in advance, and the loss of a sales opportunity due to the failure can be reduced. Can be eliminated. In addition, since the location of the failure is known in advance, it is possible to know what to prepare, such as tools and equipment, when a service person performs a treatment, which leads to more efficient maintenance work.

[Brief description of the drawings]

FIG. 1 is a schematic cross-sectional view showing a configuration outline of an open showcase according to Embodiment 1 of the present invention.

FIG. 2 is a block diagram illustrating a control configuration of the entire open showcase.

FIG. 3 is a flowchart illustrating a determination process for diagnosing the presence or absence of frost on an evaporator.

FIG. 4 is a flowchart showing a failure determination process for diagnosing clogging or the like of a condenser;

FIG. 5 is a flowchart showing a failure determination process for diagnosing an abnormality of the discharge (high pressure) side pressure of the refrigerator.

FIG. 6 is a flowchart showing a failure determination process according to Embodiment 2 of the present invention.

FIG. 7 is a diagram illustrating a difference between a change caused by a data environment and a change caused by a failure.

FIG. 8 is a diagram showing the evaporator in a state where no frost is attached.

FIG. 9 is a diagram showing the evaporator in a state where frost is attached.

FIG. 10 is a diagram showing the influence of the attachment of frost to an evaporator on the detection value of a temperature sensor in each section.

FIG. 11 is a schematic diagram showing the condenser in a state where dust is not attached.

FIG. 12 is a schematic diagram showing the condenser in a state where dust is attached.

FIG. 13 is a diagram showing a relationship between a situation of dust clogging in the condenser and a detection result of a discharge (high pressure) side temperature sensor.

FIG. 14 is a diagram showing a relationship between a situation of dust clogging in a condenser and a detection result of a discharge (high pressure) side pressure sensor.

FIG. 15 is a diagram showing a state of fluctuation between a suction (low pressure) side pressure and a discharge (high pressure) side pressure caused by a shortage (leakage) of refrigerant gas.

FIG. 16 is a diagram showing a difference in behavior between the inside temperature and the temperature-regulated temperature before and after the defrosting operation according to the presence or absence of a refrigerant gas shortage (leakage).

FIG. 17 is a diagram showing a change between the inside temperature and the temperature control temperature due to dust and dust adhering to the outlet.

FIG. 18 is a diagram showing a difference in behavior between the inside temperature and the temperature-regulated temperature caused by adhesion of dust and dust to the outlet.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Open showcase 2 Main body 3 Display shelf 4 Opening 5 Refrigerator 6 Refrigerant piping 7 Evaporator 8 Blower 9 Duct 10 Outlet (honeycomb) 11 Inside 12 Suction port 13 Compressor 14 Condenser 15 Suction (low pressure) side temperature Sensor 16 Suction (low pressure) side pressure sensor 17 Discharge (high pressure) side temperature sensor 18 Discharge (high pressure) side pressure sensor 19 Outside air temperature thermistor 20 Internal temperature thermistor 21 Temperature thermistor 22 Defrosting temperature thermistor 30 Control Device 31 CPU 32 ROM 33 RAM 35 Alarm 50 Refrigerator control circuit f Frost d Garbage

 ──────────────────────────────────────────────────続 き Continued on the front page F term (reference) 3L045 AA02 BA01 CA02 DA02 EA01 LA06 LA14 LA17 LA18 MA02 MA04 MA05 MA09 MA12 NA01 NA03 NA16 NA22 PA01 PA02 PA03 PA04 PA05 3L046 AA02 BA01 CA06 FB01 GB01 JA06 JA14 JA17 KA02 KA04 KA05 KA08 LA02 MA01 MA02 MA03 MA04 MA05 5H223 AA11 BB02 CC08 DD03 EE05 EE06 FF02

Claims (21)

[Claims] 1. A showcase management device for managing a showcase that generates cold air by causing a refrigerant to perform heat exchange in an evaporator and cools a storage room in which goods are displayed and stored by the cool air, wherein the storage room (Hereinafter referred to as "inside temperature") is input, and frost detection means for detecting frost formation in the evaporator based on the input data; And a frost formation notifying means for notifying that frost has occurred when detecting the frost formation. 2. The frost detection means determines a rate of change of the internal temperature, and determines that frost has occurred when the rate of change exceeds a predetermined range. The showcase management device according to claim 1, wherein: 3. The showcase management apparatus according to claim 2, wherein the frost detection means obtains the fluctuation rate based on a temperature inside the refrigerator at the beginning of the operation of the showcase. . 4. A refrigerator, comprising: a refrigerator for liquefying a refrigerant; and an evaporator, wherein the refrigerant supplied from the refrigerator is subjected to heat exchange in the evaporator to generate cool air, and goods are displayed and stored. The showcase which cools a warehouse by the cool air, inside temperature detection means which detects the temperature in the storage, and the detection result of the inside temperature detection means according to claim 1, 2, or 3 which is inputted. A showcase system, comprising: a showcase management device. 5. A refrigerator that compresses and liquefies a refrigerant by a compressor and a condenser, and generates heat by exchanging heat in the evaporator with the refrigerant supplied by the refrigerator, and blows the cool air from an air outlet. And a showcase management device that manages a storage case in which a storage space for displaying and storing products is cooled, comprising: a pressure on a discharge side of the refrigerator, a temperature of cold air blown to the showcase, and the storage space. Indicating the temperature (hereinafter referred to as the “inside temperature”), a failure estimating means for estimating the occurrence of a failure based on the input data, and a notifying means for notifying the estimation result of the failure estimating means. A showcase management device, comprising: 6. The failure estimating means includes means for determining a change amount of pressure at a discharge side of the refrigerator for each predetermined period (hereinafter referred to as “pressure change amount”) and a temperature of cold air under a predetermined specific condition. The amount of time required to lower the temperature to the temperature (hereinafter referred to as the "reduction time") for each predetermined period (hereinafter referred to as the "reduction time fluctuation amount"); (Hereinafter referred to as “time difference”) of the difference between the time required for the above and the reduction time (hereinafter referred to as “time difference”) (hereinafter referred to as “time difference fluctuation amount”). Means for calculating the amount of change in the reduction time and the amount of change in the time difference; and using the amount of change at a predetermined time as a reference value and the reference value and the change obtained in the period to be estimated for failure. The ratio with respect to the dynamic amount is calculated for each of the three items, and the relative magnitude relationship between the values of the ratio for each of the three items obtained by the variable amount ratio calculating means is calculated. And a notifying means for notifying the failure factor associated with the item having the largest value of the ratio as a result of the judgment by the ratio judging means. The showcase management device according to claim 5, wherein: 7. The notifying unit includes a storage unit that stores related information defining a correspondence between the three items and a failure factor, and stores the related information based on a result of the determination by the ratio determining unit. 7. The showcase management apparatus according to claim 6, wherein by referring to the failure factor, the failure factor associated with the item having the largest value of the ratio is acquired and its content is reported. 8. The notifying means, when the ratio of the pressure fluctuation amount is the largest, notifies at least one of clogging of the condenser and irradiation of direct sunlight as failure factors. When the ratio of the amount of change in the reduction time is the largest, as the failure factors, the shortage of the refrigerant, the turbulence of the cooling air, the temperature around the showcase is too high, and the condenser Clogging, and at least one of the blowing port clogging, and when the ratio of the time difference fluctuation amount is the largest,
The showcase management device according to claim 7, wherein at least one of clogging of the blower port and turbulence of cool air is notified as a failure factor. 9. When the refrigerator is provided with a fan for cooling the condenser and a motor for driving the fan, the notifying unit may be arranged so that the ratio with respect to the pressure fluctuation amount is the largest. 9. The showcase management device according to claim 8, wherein at least one of a failure of the motor and an effect of wind of the fan is also notified as a cause of the failure. 10. The failure estimating means includes means for determining a change amount of pressure on a discharge side of the refrigerator for each predetermined period (hereinafter, referred to as “pressure change amount”) and a temperature of cold air under a predetermined specific condition. The time required to lower the temperature (hereinafter "reduction time")
), The difference between the time required for lowering the internal temperature to the predetermined temperature and the lowering time (hereinafter, referred to as “lowering time fluctuation amount”) under the specific situation. (Hereinafter referred to as “time difference”), a fluctuation amount for each predetermined period (hereinafter referred to as “time difference fluctuation amount”), and a fluctuation amount calculation for obtaining the pressure fluctuation amount, the reduction time fluctuation amount, and the time difference fluctuation amount. Means, and using the amount of change at a predetermined time as a reference value, the ratio between the reference value and the amount of change obtained during the period for which the failure is estimated is calculated for each of the three items. Quantitative ratio calculating means, cumulative value calculating means for calculating the cumulative value of the ratio value obtained by the fluctuation amount ratio calculating means for each of the three items, and three terms obtained by the cumulative value calculating means And a cumulative value determining means for determining a relative magnitude relationship of each of the cumulative values, wherein the notifying means determines the cumulative value as a result of the determination by the cumulative value determining means. 6. The showcase management apparatus according to claim 5, wherein a failure factor associated with the item having the largest value is reported. 11. The notifying means has a storage means for storing related information defining a correspondence between the three items and the cause of the failure, and based on a result of the judgment by the accumulated value judging means, 11. The showcase management apparatus according to claim 10, wherein a failure factor associated with the item having the largest cumulative value is obtained by referring to the information, and the content of the failure factor is reported. 12. 12. The notifying unit, when the cumulative value of the pressure fluctuation amount is the largest, at least one of clogging of the condenser and irradiation of direct sunlight as failure factors. When the cumulative value of the amount of change in the reduction time is the largest, as a failure factor, shortage of the refrigerant, turbulence of the cool air, and that the temperature around the showcase is too high, Notifying at least one of the clogging of the condenser and the clogging of the blower port.If the cumulative value of the time difference fluctuation amount is the largest, the blower is regarded as a failure factor. The showcase management device according to claim 11, wherein at least one of clogging of a mouth and turbulence of cool air is notified. 13. When the refrigerator is provided with a fan for cooling the condenser and a motor for driving the fan, the notification means has the largest cumulative value of the pressure fluctuation amount. 13. The showcase management apparatus according to claim 12, wherein at least one of a failure of the motor and an influence of a wind of the fan is notified as a failure factor in the case. 14. The fluctuation amount calculating means obtains a representative value of each of the pressure on the discharge side, the reduction time, and the time difference for each predetermined period, and calculates a difference between the representative values for each period. The difference is obtained as the variation amount.
3. The showcase management device according to any one of 3. 15. The showcase management device according to claim 14, wherein the representative value is an average value or a maximum value in the period. 16. An operation rate calculating means for obtaining a ratio of time during which the refrigerant is supplied to the evaporator (hereinafter referred to as an "operation rate"), and an operation calculated by the operation rate calculating means. A condition that the rate is equal to or higher than a predetermined reference operation rate (hereinafter referred to as “condition A”) and a state where the temperature of the cool air is equal to or higher than the predetermined temperature have continued for a predetermined time or longer. (Hereinafter referred to as “condition B”), and condition determining means for determining whether both the condition A and the condition B are satisfied. As a result,
The show according to any one of claims 6 to 15, wherein the failure factor corresponding to the item is notified only when both the condition A and the condition B are satisfied. Case management device. 17. The condition determining means further sets a condition that a state in which the internal temperature is equal to or higher than a predetermined temperature has continued for a predetermined time or more (hereinafter, “condition C”). The notifying unit determines whether or not at least one of the condition A and the condition B is satisfied as a result of the determination by the condition determining unit. 17. The showcase management apparatus according to claim 16, wherein when the condition C is satisfied, the fact that the temperature around the showcase is high is notified as a failure factor. 18. A refrigerator comprising: a compressor and a condenser, wherein the refrigerator compresses the refrigerant by the compressor and liquefies the refrigerant by radiating the compressed refrigerant by the condenser; and an evaporator. A cooling case that generates cold air by causing the refrigerant supplied from the evaporator to perform heat exchange in the evaporator, and blows out the cold air from an air outlet to cool a storage space in which products are displayed and stored, and a discharge of the refrigerator. Pressure detection means for detecting the pressure on the side, cold air temperature detection means for detecting the temperature of the cold air, internal temperature detection means for detecting the temperature in the storage, the pressure detection means, the cold air temperature detection means and The detection result of the said inside temperature detection means is input, The Claims 5-1.
7. A showcase system, comprising: the showcase management device according to any one of 7. 19. A compressor for liquefying the refrigerant by the compressor, and when the pressure value on the discharge side is equal to or higher than a predetermined threshold value, the operating state is changed to protect itself. In a showcase management device that manages a refrigerator having a function of performing a protection operation and a showcase that is cooled using a refrigerant supplied from the refrigerator, data indicating a pressure on a discharge side of the refrigerator is provided. Enter
A showcase management device, comprising: a refrigerator abnormality detection and notification unit that detects and reports abnormality of the refrigerator. 20. The refrigerator abnormality detection notification means determines whether or not the pressure value on the discharge side of the refrigerator exceeds the threshold value at which the protection operation is started based on the input data. 20. The show according to claim 19, further comprising: a pressure determination unit that performs the pressure determination, and a pressure abnormality notification unit that notifies that the threshold is exceeded when the determination by the pressure determination unit exceeds the threshold. Case management device. 21. A compressor for liquefying the refrigerant by the compressor, and when the pressure value on the discharge side is equal to or higher than a predetermined threshold, the operating state is changed to protect itself. A refrigerator that performs a protection operation; a showcase in which a storage housing in which products are displayed and stored using the refrigerant supplied from the refrigerator is cooled; and a pressure detection unit that detects a pressure on a discharge side of the refrigerator. 20. A detection result of the pressure detecting means is input.
Or a showcase management device according to claim 20.