JP2007085609A - Cooling system - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a cooling system capable of searching the cause of a cooling abnormality occurring in each refrigerating/freezing equipment. <P>SOLUTION: As data for searching the cause of a cooling abnormality occurring in each of the refrigerating/freezing equipments 1-4, because only "data concerning temperatures inside each of the refrigerating/freezing equipments 1-4" transmitted from each of the refrigerating/freezing equipments 1-4 to a control device 6 and "data concerning opening/closing of solenoid valves 1c-4c" are used, there is no need for providing a sensor especially for abnormality detection for each structuring element which could be a source of the cause, and based on data which can be obtained from each of the refrigerating/freezing equipments 1-4, the cause of the cooling abnormality occurring in each of the refrigerating/freezing equipments 1-4 can be retrieved. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a cooling system including a plurality of refrigerated refrigerators, a shared refrigerator, and a management device that manages the operation of each refrigerator-freezer and the shared refrigerator.

  This type of cooling system includes a plurality of refrigerated refrigeration equipment composed of a refrigerated showcase, a freezer with a door, etc., a common refrigeration machine that can supply refrigerant to the evaporator of each refrigerated refrigeration equipment, Each refrigeration equipment and a management device that manages the operation of the common refrigerator by data communication with the common refrigerator.

  Each refrigeration unit detects an evaporator, an expansion means, an opening / closing means such as a solenoid valve for controlling refrigerant intake into the evaporator, an internal fan for circulating cooling air, and an internal temperature And a controller for controlling the opening and closing of the opening and closing means based on the temperature difference between the internal temperature detected by the temperature sensor and the set cooling temperature, and for transmitting operating state data to the management device.

  The common refrigerator includes a variable capacity compressor, a condenser, a pressure sensor that detects the suction pressure (refrigerant pressure on the low pressure side) of the compressor, and the suction pressure detected by the pressure sensor and the set suction pressure. And a controller for controlling the capacity of the compressor based on the pressure difference and transmitting the operation state data to the management device.

  The management device transmits various setting data for each refrigeration refrigerator and common refrigerator, and transmits the setting data to each refrigerator refrigerator and common refrigerator as well as from each refrigerator refrigerator and common refrigerator. Control means for grasping the state of the entire system based on the obtained operation state data.

The evaporator of each refrigeration unit is connected in parallel to the refrigerant outlet and the refrigerant inlet of the common refrigerator through the refrigerant forward pipe and the refrigerant return pipe, and the controller of each refrigeration unit and the common refrigerator is a communication line. To the control means of the management apparatus.
JP-A-8-61814

  By the way, during the operation of the cooling system, each refrigeration equipment is, for example, insufficient cooling or excessive cooling due to abnormalities in components such as an evaporator, expansion means, opening / closing means, internal fan, temperature sensor, ventilation filter, etc. This causes abnormal cooling. In order to avoid the product from being thermally damaged by this cooling abnormality, it is necessary to quickly search for the cause of the occurrence of the cooling abnormality.

  If an abnormality detection sensor is provided for each component that can be the cause, the cause can be directly identified based on the data obtained through each sensor. Since it is necessary to install each sensor for detection, the cost is high, and there is a trouble in performing data processing corresponding to the number of sensors on the management apparatus side.

  The present invention was created in view of the above circumstances, and the object of the present invention is based on data that can be obtained from each refrigeration unit without providing a dedicated sensor for abnormality detection in each component that can be a cause. Another object of the present invention is to provide a cooling system capable of searching for the cause of cooling abnormality occurring in each refrigeration equipment.

  In order to achieve the above object, the present invention is a cooling system including a plurality of refrigeration refrigerators, a common refrigerator, and a management device that manages the operation of each refrigerator refrigerator and a common refrigerator. The refrigeration equipment includes an evaporator, opening / closing means for controlling refrigerant intake into the evaporator, an internal fan for circulating cooling air, a temperature sensor for detecting the internal temperature, and the internal temperature And a means for controlling opening and closing of the opening and closing means based on a temperature difference between the set cooling temperature and a means for transmitting data relating to opening and closing of the opening and closing means and data relating to the internal temperature to the management apparatus, It is characterized by comprising means for searching for the cause of the cooling abnormality occurring in each refrigeration equipment using data relating to opening / closing of the opening / closing means transmitted from each refrigeration equipment and data relating to the internal temperature. .

  According to this cooling system, only the data relating to the internal temperature of each refrigerated refrigeration equipment and the data relating to the opening / closing of the opening / closing means transmitted from each refrigeration refrigeration equipment to the management device as data for searching for the cause of the cooling abnormality Searching for causes of cooling abnormalities occurring in each refrigerated refrigeration equipment based on data available from each refrigerated refrigeration equipment without providing a dedicated sensor for abnormality detection in each component that can be the cause Can do.

  According to the present invention, it is possible to search for the cause of a cooling abnormality occurring in each refrigeration equipment based on data available from each refrigeration equipment without providing a sensor dedicated to abnormality detection for each component that can be a cause. A cooling system can be provided.

  The above object and other objects, structural features, and operational effects of the present invention will become apparent from the following description and the accompanying drawings.

  1 and 2 show an embodiment of the present invention. FIG. 1 is an overall view of the cooling system, and FIG. 2 is a flowchart of abnormality cause notification.

  First, the entire configuration of the cooling system will be described with reference to FIG. In FIG. 1, 1 to 4 are refrigerated refrigerators, 5 is a shared refrigerator, 6 is a management device, RP1 is a refrigerant forward pipe, RP2 is a refrigerant return pipe, and SL1 and SL2 are communication lines.

  The refrigeration equipment 1 to 4 includes a refrigerated showcase, a freezer with a door, and the like, and is installed at a predetermined position in the store. Each refrigeration equipment 1-4 includes evaporators 1a to 4a, expansion means 1b to 4b such as expansion valves and capillary tubes provided on the inlet side of the evaporators 1a to 4a, and inlet side of the expansion means 1b to 4b. Solenoid valves 1c to 4c provided in the cabinet, internal fans 1d to 4d for circulating cooling air, temperature sensors 1e to 4e for detecting the internal temperature (blowing temperature), and cooling air outlets And a ventilation filter (not shown) provided in the suction port, and controllers 1f to 4f. The evaporators 1a to 4a of the respective refrigeration refrigerators 1 to 4 are connected in parallel to the refrigerant outlet and the refrigerant inlet of the common refrigerator 5 through the refrigerant forward pipe RP1 and the refrigerant return pipe RP2. Here, the solenoid valves 1c to 4c correspond to “opening / closing means for controlling refrigerant intake into the evaporator” in the claims.

  Each controller 1f-4f has a control part of a microcomputer configuration, a communication part, a drive part, and a detection part, and each communication part is connected to management device 6 via communication line SL1, and electromagnetic valve 1c is connected to each drive part. To 4c and the internal fans 1d to 4d are connected, and temperature sensors 1e to 4e are connected to the detection units.

  In the memories of the controllers of the controllers 1f to 4f, the temperature differences ΔT1 to ΔT4 between the set cooling temperatures Ts1 to Ts4 determined on the management device 6 side and the internal temperatures T1 to T4 detected by the temperature sensors 1e to 4e. , A cooling program for controlling the opening and closing of the solenoid valves 1c to 4c, and operating state data including data relating to the opening and closing of the solenoid valves 1c to 4c and data relating to the internal temperatures T1 to T4 are transmitted to the management device 6. A communication program or the like is stored.

  The common refrigerator 5 includes a variable capacity compressor 5a, a condenser 5b, a pressure sensor 5c for detecting the suction pressure (low pressure side refrigerant pressure) of the compressor 5a, and a controller 5d. The common refrigerant 5 has an outlet for refrigerant (exit side of the condenser 5b) connected to the proximal end of the refrigerant forward pipe RP1, and an inlet for refrigerant (inlet side of the compressor 5a) connected to the end of the refrigerant return pipe RP2. Has been.

  The controller 5d includes a control unit having a microcomputer configuration, a communication unit, a drive unit, and a detection unit. The communication unit is connected to the management device 6 via the communication line SL2, and the compressor 5a is connected to the drive unit. A pressure sensor 5d that detects the suction pressure (low-pressure side refrigerant pressure) of the compressor 5a is connected to the detection unit.

  In the memory of the controller of the controller 5d, the capacity of the compressor 5a is controlled based on the pressure difference ΔP between the set suction pressure Ps determined on the management device 6 side and the suction pressure P detected by the pressure sensor 5c. And a communication program for transmitting operation state data including data related to the suction pressure P to the management device 6 are stored.

  The management device 6 includes a control unit 6a having a microcomputer configuration, a setting unit 6b including input keys and a display, a communication unit 6c, and a connector 6d connected to the communication unit 6c. The ends of the communication lines SL1 and SL2 are connected to the connector 6d.

  The memory of the control unit 6a includes a temperature setting program for manually setting the set cooling temperatures Ts1 to Ts4 for each of the refrigeration units 1 to 4, and a pressure setting program for automatically setting the set suction pressure Ps. In addition, a communication program for transmitting the set cooling temperatures Ts1 to Ts4 to the respective refrigeration refrigerators 1 to 4 and transmitting the set suction pressure Ps to the common refrigerator 5 is stored.

  Next, the cooling operation of each refrigeration equipment 1 to 4 will be described taking the refrigeration equipment 1 as an example. The cooling operation of the other refrigerated refrigerators 2 to 4 whose explanation is omitted is performed in the same manner as described below.

  The set cooling temperature Ts1 transmitted from the management device 6 is stored in the memory of the controller 1f of the refrigerated refrigeration equipment 1, and the set cooling temperature Ts1 is transmitted from the management device 6 every time a new set cooling temperature Ts1 is transmitted. To be rewritten.

  The refrigerated refrigerator 1 compares the internal temperature T1 detected by the temperature sensor 1e with the set cooling temperature Ts1, and when T1> Ts1 (upper limit), the solenoid valve 1c is opened, and T1 ≦ Ts1 (lower limit). At that time, the solenoid valve 1c is closed. When the solenoid valve 1c is opened, the refrigerant is taken into the evaporator 1a from the refrigerant forward pipe RP1 via the expansion means 1b, and thereby the products displayed in the cabinet are cooled. On the other hand, when the solenoid valve 1c is closed, the intake of the refrigerant from the refrigerant forward pipe RP1 to the evaporator 1a is blocked, thereby suppressing the cooling.

  Next, the operation of the compressor 5a of the common refrigerator 5 will be described.

  The set suction pressure Ps transmitted from the management device 6 is stored in the memory of the common refrigerator 5d, and the set suction pressure Ps is rewritten every time a new set suction pressure Ps is transmitted from the management device 6.

  The common refrigerator 5 compares the suction pressure P detected by the pressure sensor 5c with the set suction pressure Ps, and varies the capacity of the compressor 5a so that the suction pressure P becomes the set suction pressure Ps. The refrigerant condensed by the condenser 5b by the operation of the compressor 5a is sent to the refrigerant forward pipe RP1, and the refrigerant after being evaporated by the evaporators 1a to 4a of the refrigeration refrigerators 1 to 4 is compressed through the refrigerant return pipe RP2. Return to machine 5a.

  Next, with reference to FIG. 2, a method for searching for the cause of the cooling abnormality occurring in each of the refrigerated refrigeration apparatuses 1 to 4 when the cooling system is operating will be described by taking the refrigerated refrigeration apparatus 1 as an example. The cause search for the cooling abnormality here is performed on the management device 6 side using the operation state data transmitted from the refrigeration equipment 1 to the management device 6. The search for the cause of the cooling abnormality of the other refrigerated refrigerators 2 to 4 whose explanation is omitted is performed in the same manner as described below.

  First, it is determined whether or not the internal temperature T1 included in the operation state data is within a normal temperature range defined by the minimum temperature Tm1 and the maximum temperature Tg1 (step ST1).

  The normal temperature range here is determined based on a temperature lower than the minimum value of the internal temperature T1 that can actually occur and a temperature higher than the maximum value. For example, −30 ° C. to + 40 ° C. is the range. Used. In addition, this normal temperature range may be defined for every refrigeration equipment 1-4, and may be defined as a common range with all the refrigeration equipment.

  When the internal temperature T1 is lower than the minimum temperature Tm1 or higher than the maximum temperature Tg1, the temperature sensor 1e does not detect any temperature signal, and the temperature sensor 1e does not detect any temperature. Assuming that a defect has occurred, the fact that the temperature sensor 1e is abnormal is displayed on the display of the setting unit 6b with characters or the like (step ST2). In addition, when two or more temperature sensors are provided in one refrigeration equipment, any temperature sensor may be abnormal when the difference between detected temperatures of a plurality of temperature sensors exceeds a certain value. May be displayed.

  Subsequently, the opening duration (time from opening to closing) t1 of the solenoid valve 1c obtained based on the data related to the opening and closing of the solenoid valve 1c included in the operation state data is defined by the shortest time tm1 and the longest time tg1. It is determined whether or not it is within a normal time range (step ST3).

  The normal time range here is determined based on a time shorter than the minimum value of the opening duration time t1 that can actually occur and a time longer than the maximum value. For example, 10 seconds to 6 hours is used as the range. In addition, this normal time range may be defined for each of the refrigeration refrigerators 1 to 4, or may be determined as a common range for all the refrigeration refrigerators. Further, it is determined whether or not the closing time (time from closing to opening) of the solenoid valve 1c is within the normal time range instead of the opening duration, or both the opening duration and the closing duration are You may make it discriminate | determine whether it exists in a normal time range.

  If the opening duration t1 is shorter than the shortest time tm1 or longer than the longest time tg1, it is considered that the solenoid valve 1c or its driver has malfunctioned and the solenoid valve 1c is abnormal. Is displayed on the display of the setting unit 6b with characters or the like (step ST4).

  Subsequently, the open time ratio (excluding defrosting and immediately after the end of defrosting) r1 obtained based on the total opening duration per unit time of the solenoid valve 1c included in the operating state data is the minimum value rm1 and the maximum It is determined whether or not it is larger than the maximum value rg1 of the normal time ratio range defined by the value rg1 (steps ST5 and ST7).

  The normal time ratio range here is determined based on a value lower than the minimum value of the open time ratio r1 that can actually occur and a value larger than the maximum value. For example, 10% to 90% is the range. Used. The past 12 hours and the past 24 hours are used as the unit time for obtaining the open time ratio. In addition, this normal time ratio range may be defined for each of the refrigeration refrigerators 1 to 4, or may be determined as a common range for all the refrigeration refrigerators. Further, instead of the opening time ratio, the blocking time ratio (excluding defrosting and immediately after the completion of defrosting) is obtained based on the total closing duration per unit time of the solenoid valve, and the blocking time ratio is within the normal time ratio range. It may be determined whether or not both the open time ratio and the closed time ratio are within the normal time range.

  When the open time ratio r1 is larger than the maximum value rg1, the evaporator 1a and the temperature sensor are regarded as being caused by excessive frost formation in the evaporator 1a, position misalignment of the temperature sensor 1e, or refrigerant leakage in the refrigerant path. 1e, The fact that the refrigerant path is abnormal is displayed with characters or the like on the display of the setting unit 6b (step ST6).

  On the other hand, when the open time ratio r1 is smaller than the minimum value rm1, it is considered that the internal fan 1d is malfunctioning or the ventilation filter is clogged, and the internal fan 1d and the ventilation filter are abnormal. The effect is displayed on the display of the setting unit 6b with characters or the like (ST8).

  Subsequently, the temperature gradient g1 at the time of cooling obtained based on the decrease in the internal temperature T1 within the time during which the electromagnetic valve 1c is open is within the normal gradient range defined by the minimum value gm1 and the maximum value gg1. (STEP ST9, ST11).

  The normal gradient range here is determined based on a value lower than the minimum value of the temperature gradient g1 that can actually occur and a value larger than the maximum value. For example, 20% to 80% is used as the range. . In addition, this normal gradient range may be defined for every refrigeration equipment 1-4, and may be defined as a common range with all the refrigeration equipment.

  If the temperature gradient g1 during cooling is larger than the maximum value gg1, it is considered that the internal fan 1d is malfunctioning or the ventilation filter is clogged, and the internal fan 1d and the ventilation filter are abnormal. A message to the effect is displayed on the display of the setting unit 6b with characters (step ST10).

  On the other hand, when the temperature gradient g1 at the time of cooling is smaller than the minimum value gm1, it is considered that the evaporator 1a has excessive frost formation, the position of the temperature sensor 1e is poor, or the refrigerant leaks in the refrigerant path. 1a, the temperature sensor 1e, and the fact that the refrigerant path is abnormal are displayed on the display of the setting unit 6b with characters or the like (step ST12).

  Thus, according to the above-described cooling system, “each refrigeration” is transmitted from each refrigeration refrigerator 1 to 4 to the management device 6 as data for searching for the cause of the cooling abnormality occurring in each refrigeration refrigerator 1 to 4. Since only the “data related to the internal temperature of the refrigeration equipment 1 to 4” and “data related to the opening and closing of the solenoid valves 1c to 4c” are used, a sensor dedicated to abnormality detection is provided for each component that can be the cause The cause search of the cooling abnormality which occurred in each refrigeration refrigerator 1 to 4 can be performed based on the data available from each refrigeration refrigerator 1 to 4 without providing.

  In addition, based on “data related to the internal temperature of each refrigeration refrigerator 1 to 4” and “data related to the opening and closing of the solenoid valves 1c to 4c”, the quality determination of the internal temperature of each refrigeration refrigerator 1 to 4; Pass / fail judgment of the open duration (blocking duration) of the electromagnetic valves 1c to 4c of the refrigeration refrigerators 1 to 4, and pass / fail of the open time ratio (blocking time ratio) of the solenoid valves 1c to 4c of the refrigerator refrigerators 1 to 4 Since the determination and the quality determination of the temperature gradient at the time of cooling of each refrigeration equipment 1 to 4 are performed, the cause search for the cooling abnormality occurring in each refrigeration equipment 1 to 4 can be accurately performed from each determination result.

  Furthermore, since the “data related to opening / closing of the solenoid valves 1c to 4c” is processed to create a reference value for determining the quality of the open duration and a reference value for determining the quality of the open time ratio, 4, the operation state of the solenoid valves 1c to 4c, which are main components when cooling is performed, can be accurately recognized, and a highly accurate cause search can be performed.

  In the above-described embodiment, each refrigeration unit is used by using “data relating to the internal temperature of each refrigeration unit 1 to 4” and “data relating to opening / closing of the solenoid valve 1c” included in the operation state data. Judgment of pass / fail of the internal temperature of 1-4, pass / fail determination of the open duration (blocking duration) of the electromagnetic valves 1c-4c of the refrigeration refrigerators 1-4, electromagnetic valves 1c-4c of the refrigerator refrigerators 1-4 The quality of the open time ratio (blocking time ratio) and the quality judgment of the temperature gradient during cooling of each refrigerated refrigerator 1 to 4 were performed. ”And“ data related to opening / closing of the solenoid valve 1c ”may be added as appropriate to other pass / fail judgment items.

  For example, after the solenoid valve is closed by determining whether each change is normal by obtaining changes in the internal temperature after closing the solenoid valve and changes in the internal temperature after opening the solenoid valve If the internal temperature change after opening is judged as good or bad, if the internal temperature continues to decrease after closing or if the internal temperature continues to increase after opening, the expansion means, solenoid valve or its driver has malfunctioned It can be considered that the expansion means and the electromagnetic valve are abnormal.

  In the above-described embodiment, the expansion means and the electromagnetic valve are provided on the upstream side of the evaporator and the refrigerant intake into the evaporator is controlled by the electromagnetic valve. However, instead of the expansion means and the electromagnetic valve, evaporation is performed. Even when an electronic expansion means having an opening / closing function is provided on the upstream side of the container, the same effect as described above can be obtained by using data relating to the opening / closing of the electronic expansion means. In this case, the electronic expansion means corresponds to “opening / closing means for controlling refrigerant intake into the evaporator” in the claims.

  Furthermore, in the above-mentioned embodiment, although the cooling system provided with the four refrigeration refrigerators 1-4 was illustrated, even if the number of the refrigeration refrigerator apparatuses is three or less, or five or more cooling systems, this The same effects as described above can be obtained by applying the invention.

1 is an overall view of a cooling system showing an embodiment of the present invention. It is a flowchart of the abnormality cause search performed with the cooling system of FIG.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 1-4 ... Refrigerated refrigeration equipment, 1a-4a ... Evaporator, 1b-4b ... Expansion means, 1c-4c ... Solenoid valve, 1d-4d ... Inside fan, 1e-4e ... Temperature sensor, 1f-4f ... Controller, DESCRIPTION OF SYMBOLS 5 ... Common refrigerator, 5a ... Compressor, 5b ... Condenser, 5c ... Pressure sensor, 5d ... Controller, 6 ... Management apparatus, 6a ... Control part, 6b ... Setting part, 6c ... Communication part, RP1 ... Refrigerant going pipe , RP2 ... refrigerant return pipe, SL1, SL2 ... communication line.

Claims (3)

A cooling system that includes a plurality of refrigeration units, a common refrigerator, and a management device that performs operation management of each refrigeration unit and the common refrigerator,
Each refrigeration unit includes an evaporator, opening / closing means for controlling refrigerant intake into the evaporator, an internal fan for circulating cooling air, a temperature sensor for detecting the internal temperature, Means for controlling opening and closing of the opening and closing means based on the temperature difference between the internal temperature and the set cooling temperature, and means for transmitting data relating to opening and closing of the opening and closing means and data relating to the internal temperature to the management device,
The management device includes means for searching for the cause of the cooling abnormality that has occurred in each refrigeration equipment using data relating to opening and closing of the opening and closing means transmitted from each refrigeration equipment and data relating to the internal temperature.
A cooling system characterized by that. The means for searching for the cause performs pass / fail determination of the open / close means of each refrigeration refrigerator based on the data related to opening / closing of the open / close means, and searches for the cause of the cooling abnormality from the result of the pass / fail determination.
The cooling system according to claim 1. The pass / fail judgment of the opening / closing means includes at least pass / fail judgment of the opening / closing duration of the opening / closing means and a pass / fail judgment of the opening time ratio per unit time of the opening / closing means or the closure time ratio per unit time.
The cooling system according to claim 2.

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