JP2018204835A - Refrigerator - Google Patents

Abstract

To provide a refrigerator which can encourage a user to clean an air filter.SOLUTION: The present invention includes: a housing body 12 having a storage 11 in which an object to be stored is placed; a machine room 14; a cooler 26 constituting a cooling cycle 19; a condenser 21; a compressor 22; an air filter 33 stored in the machine room 14 and covering the condenser 21; a condenser fan 21A stored in the machine room 14 and cooling the condenser 21; a control part 40; and a display lamp 34 for alerting a clog of the air filter 33. The control part 40 performs: a judgement processing for judging that the air filter 33 is clogged when judgement conditions are met; and an alert processing for operating the display lamp 34 when the judgement processing judges that the air filter 33 is clogged.SELECTED DRAWING: Figure 11

Description

  The present invention relates to a cooling storage.

  Conventionally, what has a machine room is known as a cooling storage (the following patent documents 1). In the thing of patent document 1, the cooling device which consists of a condenser and a compressor is accommodated in the machine room. The machine room is opened forward, and can be opened and closed by a front panel.

Japanese Patent Laid-Open No. 2015-210055

  An air filter is attached to the condenser described above so as to cover it. When the air filter is clogged, the cooling efficiency of the cooling device is lowered, and therefore it is required to periodically clean the air filter. However, in reality, the user of the cooling storage may not confirm the state of the air filter, and the cooling operation is often performed in a state where the air filter is clogged.

  This invention is completed based on the above situations, Comprising: It aims at providing the cooling storage which can urge a user to clean an air filter.

  In order to solve the above-mentioned problems, the cooling storage of the present invention is a cooling that can cool the storage chamber by forming a box having a storage chamber in which stored items are arranged, a machine room, and a cooling cycle. , A condenser housed in the machine room and constituting the cooling cycle, a compressor housed in the machine room and constituting the cooling cycle, and an air housed in the machine room and covering the condenser A filter, a condenser fan housed in the machine room for cooling the condenser, a control unit, and a notification unit capable of reporting that the air filter is clogged, and the control A determination process for determining that the air filter is clogged when a predetermined determination condition is satisfied, and the notification when the determination process determines that the air filter is clogged. Operating part Characterized in that the run a notification process of, the. It is possible to notify the user that the air filter is clogged, and the user can be prompted to clean the air filter.

  In addition, a condenser temperature sensor capable of measuring the temperature of the condenser may be provided, and the determination condition may include that a state where the measured temperature of the condenser temperature sensor is equal to or higher than a specified value has continued for a specified time. . When the air filter is clogged, cooling of the condenser by the condenser fan is hindered, and the temperature of the condenser rises. For this reason, it can be determined whether the air filter is clogged based on the measured temperature of the condenser temperature sensor.

  Moreover, the inside temperature sensor which can measure the temperature of the said storage room is provided, and the said judgment conditions shall include that the measured temperature of the said inside temperature sensor is below a regulation value. When the temperature of the storage room is high, the temperature of the condenser increases. For this reason, the situation which misdetermines that it is clogged when the temperature of a store room is high can be suppressed by including the said determination conditions.

  In addition, an ambient temperature sensor capable of measuring the ambient temperature of the condenser is provided, and the determination condition is that a difference between a measured temperature of the condenser temperature sensor and a measured temperature of the ambient temperature sensor is a specified value or more. It may include that the state that is equal to or greater than the specified value has continued for a specified time. If the ambient temperature of the condenser is high, the temperature of the condenser increases. For this reason, by including the above-described determination conditions, it is possible to suppress a situation in which the air filter is erroneously determined to be clogged when the air filter is not clogged and the ambient temperature is high.

  In addition, a cooler outlet temperature sensor capable of measuring the outlet temperature of the cooler may be provided, and the determination condition may include that the measured temperature of the cooler outlet temperature sensor is a specified value or less. When the outlet temperature (coolant temperature) of the cooler increases as the temperature in the storage chamber increases, the temperature of the condenser increases. For this reason, the situation which misdetermines that it is clogged when the exit temperature of a cooler is high can be suppressed by including the above-mentioned judgment conditions.

  And a door opening / closing detection sensor capable of detecting opening / closing of the door, the door opening / closing detection sensor being capable of detecting opening / closing of the door. It may include detecting a closed state. When the door is open, the temperature of the storage room increases and the temperature of the condenser increases. For this reason, the situation which misdetermines that it is clogged when the door is open can be suppressed by including the above-mentioned determination conditions.

  Moreover, the inside temperature sensor which can measure the temperature of the said storage room is provided, and the said judgment conditions shall include that the measured temperature of the said inside temperature sensor is falling. When the door is opened, for example, the temperature of the storage chamber rises and the condensation temperature rises. Therefore, even when the air filter is not clogged, the temperature of the condenser rises. The state where the temperature measured by the internal temperature sensor is decreasing can be considered as a state where there is no cause for the temperature increase in the storage room. For this reason, the situation which misdetermines that it is clogged when the temperature of the store room is rising can be suppressed by including the said determination conditions.

  Further, the determination condition is that a difference between a measured temperature of the condenser temperature sensor when the compressor is operating and a measured temperature of the condenser temperature sensor when the compressor is stopped is a specified value. It can include the above. If the ambient temperature of the condenser is high, the temperature of the condenser increases. Also, since there is no exhaust heat from the compressor and the condenser when the compressor is stopped, the measured temperature of the condenser temperature sensor when the compressor is stopped is regarded as the ambient temperature of the condenser. Can do. For this reason, by including the above-described determination conditions, it is possible to suppress the erroneous determination that the air filter is clogged when the air filter is not clogged and the ambient temperature is high.

  Further, the determination condition is that the measured temperature of the condenser temperature sensor when the compressor is stopped and the measured temperature of the condenser temperature sensor immediately after the measured temperature of the condenser temperature sensor become constant. It may include that the difference from the measurement temperature is a specified value or more. If the ambient temperature of the condenser is high, the temperature of the condenser increases. In addition, since there is no exhaust heat from the compressor and the condenser when the compressor is stopped, the condenser temperature sensor at the time when the measured temperature of the condenser temperature sensor becomes constant immediately after the compressor stops. The measured temperature can be regarded as the ambient temperature of the condenser. For this reason, by including the above-described determination conditions, it is possible to suppress the erroneous determination that the air filter is clogged when the air filter is not clogged and the ambient temperature is high. And according to the above determination conditions, since the determination process can be performed at the time when the measured temperature of the condenser temperature sensor becomes constant immediately after the compressor is stopped, the surroundings of the condenser at the time when the determination process is performed A determination process based on the temperature can be performed.

  Further, the determination condition may include a determination condition based on the number of rotations of a motor that rotates the condenser fan. If the motor is a motor whose rotation speed can be controlled by inverter control or the like and the command rotation speed for the motor can be increased (in other words, the command rotation speed is less than the upper limit value), the air filter When the temperature of the condenser rises due to clogging, the control unit generally attempts to lower the condenser temperature by increasing the motor rotation speed (increasing the indicated rotation speed). For this reason, when the instruction | indication rotation speed with respect to a motor can be increased, when the real rotation speed of a motor becomes more than a regulation value, it can determine with the air filter being clogged.

  Further, when the air filter is clogged, the air flow through the air filter is hindered, resulting in an increase in air resistance when the condenser fan rotates. For this reason, if the command rotation speed of the motor is the upper limit value (maximum rotation speed) of the setting range and the air filter is clogged, the motor rotation speed cannot be increased any more, while the condenser fan Since the air resistance of the motor increases, the actual rotational speed of the motor decreases. For this reason, when the motor's command speed is the upper limit (maximum speed) of the setting range, the difference between the motor's command speed and the actual motor speed is greater than or equal to the specified value. In this case, it can be determined that the air filter is clogged.

  The determination condition may include a determination condition based on the wind speed of the condenser fan measured by the wind speed sensor. In addition, the determination condition may include a determination condition based on the air flow rate of the condenser fan measured by the air volume sensor. Since the wind speed and air volume of the condenser fan are basically proportional to the actual rotational speed of the condenser fan, the concept is similar to the above judgment condition based on the actual rotational speed of the condenser fan (motor). The clogging of the air filter can be determined based on the wind speed or air volume of the condenser fan. When the air filter is clogged, even if the actual rotation speed of the condenser fan (motor) is constant, the air flow is obstructed, so that the air speed is measured by the wind speed sensor and the air volume sensor. Even if this is the case, it is determined that the air filter is clogged even if the wind speed (or air volume) of the condenser fan falls below the specified value. be able to.

  Further, the determination condition may include that a state in which a current flowing through a motor for rotating the condenser fan is equal to or greater than a specified value has continued for a specified time. When the air filter is clogged, cooling of the condenser by the condenser fan is hindered, and the temperature of the condenser rises. At this time, if the motor is a motor whose rotation speed can be controlled by inverter control or the like, and the instruction rotation speed for the motor can be increased, the control unit increases the rotation speed of the motor. Try to lower the condenser temperature. Since the magnitude of the current flowing through the motor is proportional to the rotational speed of the motor, it can be determined whether or not the air filter is clogged based on the current flowing through the motor.

  On the other hand, when the indicated rotational speed of the motor is the upper limit (maximum rotational speed) of the setting range (or when a constant speed motor is used), if the air filter is clogged, the condenser fan will rotate. As the air resistance increases, the current flowing through the motor increases. For this reason, it can be determined whether the air filter is clogged based on the current flowing through the motor.

  Moreover, it can include that the state where the measured temperature of the motor temperature sensor is equal to or higher than a specified value has continued for a specified time. When the air filter is clogged, the current flowing through the motor increases as described above. Since the motor temperature is proportional to the motor current, it can be determined whether the air filter is clogged based on the measured temperature of the motor temperature sensor.

  Further, the determination condition may include that an integrated value of the number of rotations of the condenser fan is a specified value or more. As the integrated value of the number of rotations of the condenser fan is higher, dust or the like is likely to accumulate in the air filter. For this reason, it can be determined whether the air filter is clogged based on the integrated value of the rotation speed of the condenser fan.

  A condenser inlet temperature sensor capable of measuring an inlet temperature of the condenser; and a condenser outlet temperature sensor capable of measuring an outlet temperature of the condenser, wherein the determination condition is the condenser inlet temperature sensor. The state in which the difference between the measured temperature of the condenser and the measured temperature of the condenser outlet temperature sensor is equal to or less than a specified value may include that the state has continued for a specified time. When the air filter is clogged, cooling of the condenser by the condenser fan is hindered, so that the difference between the condenser inlet temperature and the condenser outlet temperature is reduced. For this reason, it can be determined whether the air filter is clogged based on the measured temperature of the condenser inlet temperature sensor and the measured temperature of the condenser outlet temperature sensor.

  The air filter and the compressor are arranged along a blowing direction of the condenser fan, and include a compressor temperature sensor capable of measuring the temperature of the compressor, and the determination condition includes the compressor It can include that the state in which the temperature measured by the temperature sensor is equal to or higher than a specified value has continued for a specified time. The wind generated by the condenser fan is arranged so as to pass through the air filter and be sent to the compressor. When the air filter is clogged, air blowing to the compressor is hindered, and the temperature of the compressor is likely to rise. For this reason, it can be determined whether the air filter is clogged based on the measured temperature of the compressor temperature sensor.

  The determination condition may include that the continuous operation time of the compressor is a specified value or more. When the air filter is clogged, the cooling efficiency of the cooling cycle is lowered, and therefore the continuous operation time of the cooling cycle tends to be long. For this reason, it can be determined whether the air filter is clogged based on the continuous operation time of the compressor.

  Further, the determination condition may include that the state where the rotation speed of the compressor is equal to or higher than a specified value has continued for a specified time. When the air filter is clogged, the cooling efficiency of the cooling cycle is lowered, and therefore the rotational speed of the compressor tends to be high. For this reason, it can be determined whether the air filter is clogged based on the rotation speed of the compressor.

  Further, a color sensor capable of identifying the color of the air filter is provided, and the determination condition may include that the color of the air filter identified by the color sensor becomes a specified color. When the air filter is clogged, the color of the air filter changes due to dust or dirt. For this reason, it can be determined whether the air filter is clogged based on the color of the air filter.

  In addition, a light reflectance sensor capable of measuring the light reflectance of the air filter is provided, and the determination condition is that the light reflectance of the air filter measured by the light reflectance sensor is a specified value or less. Can be included. When the air filter is clogged, the light reflectance of the air filter decreases. For this reason, it can be determined whether the air filter is clogged based on the light reflectance of the air filter.

  In addition, a light transmittance sensor capable of measuring the light transmittance of the air filter is provided, and the determination condition is that the light transmittance of the air filter measured by the light transmittance sensor is not more than a specified value. Can be included. When the air filter is clogged, the light transmittance of the air filter decreases. For this reason, it can be determined whether the air filter is clogged based on the light transmittance of the air filter.

  Further, a distance sensor capable of measuring a distance to the surface of the air filter is provided, and the determination condition includes that the distance to the surface of the air filter measured by the distance sensor is equal to or less than a specified value. be able to. When the air filter is clogged, dust or the like accumulates on the surface of the air filter, and the distance between the surface of the air filter and the distance sensor becomes small. For this reason, it can be determined whether the air filter is clogged based on the distance measured by the distance sensor.

  In addition, a weight sensor capable of measuring the weight of the air filter is provided, and the determination condition includes that the weight of the air filter measured by the weight sensor is equal to or greater than a specified value. When the air filter is clogged, dust or the like accumulates on the surface of the air filter, so that the weight of the air filter increases. For this reason, it can be determined whether the air filter is clogged based on the weight measured by the weight sensor.

  The condenser is disposed between the air filter and the condenser fan, and the condenser fan is configured to direct air sucked through the air filter to the condenser. And a pressure sensor capable of measuring the pressure in the space between the condenser fan and the determination condition includes that the pressure in the space measured by the pressure sensor is equal to or less than a specified value. it can. When the air filter is clogged, the amount of air sucked into the condenser through the air filter is reduced. As a result, the pressure in the space between the condenser and the condenser fan decreases. For this reason, it can be determined whether the air filter is clogged based on the pressure of the space measured by the pressure sensor.

  In addition, a compressor outlet temperature sensor capable of measuring the outlet temperature of the compressor is provided, and the determination condition is that the outlet temperature of the compressor measured by the compressor outlet temperature sensor is not less than a specified value. Can be included. When the air filter is clogged, the outlet temperature of the compressor rises. Based on this, it can be determined whether or not the air filter is clogged.

  Further, a compressor inlet temperature sensor capable of measuring the inlet temperature of the compressor is provided, and the determination condition is that the inlet temperature of the compressor measured by the compressor inlet temperature sensor is not less than a specified value. Can be included. If the air filter is clogged, the inlet temperature of the compressor rises. Based on this, it can be determined whether or not the air filter is clogged.

  Moreover, the high pressure sensor which can measure the high pressure of the said cooling cycle is provided, The said judgment conditions shall include that the high pressure measured by the said high pressure sensor becomes more than a regulation value. When the air filter is clogged, the high pressure increases, so it can be determined whether the air filter is clogged based on the high pressure.

  In addition, a low pressure sensor capable of measuring the low pressure of the cooling cycle may be provided, and the determination condition may include that the low pressure measured by the low pressure sensor becomes a specified value or more. When the air filter is clogged, the low pressure increases, so it can be determined whether the air filter is clogged based on the low pressure.

  The determination condition may include that the degree of superheat of the refrigerant in the cooler is equal to or higher than a specified value. When the air filter is clogged, cooling of the condenser by the condenser fan is hindered, so that the temperature of the refrigerant toward the cooler increases and the degree of superheat in the cooler increases. For this reason, it can be determined whether the air filter is clogged based on the degree of superheat.

  In addition, a refrigerant flow rate sensor capable of measuring a refrigerant circulation amount in the cooling cycle is provided, and the determination condition includes that the refrigerant circulation amount measured by the refrigerant flow rate sensor is equal to or greater than a specified value. . When the air filter is clogged, the circulation amount of the refrigerant increases. For this reason, it can be determined whether the air filter is clogged based on the circulation amount of the refrigerant.

  In addition, a refrigerant flow rate sensor capable of measuring a refrigerant flow rate in the cooling cycle may be provided, and the determination condition may include that the refrigerant flow rate measured by the refrigerant flow rate sensor becomes a specified value or more. When the air filter is clogged, the circulation amount of the refrigerant increases and the flow rate of the refrigerant increases. For this reason, it can be determined whether the air filter is clogged based on the flow rate of the refrigerant.

  Further, the determination condition may include that the pressure loss of the refrigerant in the cooling cycle is equal to or higher than a specified value. When the air filter is clogged, the circulation amount of the refrigerant increases and the flow rate of the refrigerant increases, so that the pressure loss of the refrigerant increases. For this reason, it can be determined whether the air filter is clogged based on the pressure loss of the refrigerant.

  Moreover, the operation | movement stop part which can stop operation | movement of the said alerting | reporting part shall be provided. It is possible to stop the operation of the notification unit at an arbitrary timing.

  Further, the control unit may not execute the notification process for a predetermined time after the operation of the notification unit is stopped by the operation stop unit. When the operation of the notification unit is stopped, there is a high possibility that the user has cleaned the air filter. For this reason, it can be considered that the possibility that the air filter is clogged is low during the specified time after the operation of the notification unit is stopped. For this reason, by not performing the notification process for a specified time after the operation of the notification unit is stopped, it is possible to suppress a situation in which it is erroneously determined that the air filter is clogged and the notification process is executed.

  Moreover, the said control part shall operate | move the said alerting | reporting part after predetermined time progress, after the operation | movement of the said alerting | reporting part is stopped. By periodically operating the notification unit, it is possible to periodically prompt the user to clean the air filter.

  Moreover, the said control part shall stop operation | movement of the said alerting | reporting part after progress of the alerting | reporting process after regulation time progress. There is no need for the user to perform the operation of stopping the notification unit.

  In addition, an air filter attachment detection sensor capable of detecting that the air filter is attached so as to cover the condenser, and the control unit detects that the air filter is attached. The notification section can be operated after a predetermined time has elapsed since the detection. When the air filter is attached, there is a high possibility that the air filter has been cleaned by the user. For this reason, it is possible to prompt the user to clean the air filter after the lapse of the specified time since the previous cleaning of the air filter by operating the notification unit after the lapse of the specified time after detecting that the air filter is attached. .

  According to the present invention, the user can be prompted to clean the air filter.

The front view which shows the cooling storehouse which concerns on one Embodiment of this invention. Side sectional view showing the cooling storage Perspective view showing the operation box Schematic diagram showing the cooling cycle of the cooling storage Block diagram showing a part of the electrical configuration of the cooling storage Side view showing light reflectance sensor Side view showing light transmittance sensor Side view showing distance sensor Side view showing weight sensor Side view showing proximity sensor Flow chart showing processing of control unit Timing chart showing processing of control unit according to determination condition (1) Timing chart showing processing of control unit according to determination condition (3) Timing chart showing processing of control unit according to determination condition (2) Timing chart showing processing of control unit according to determination condition (5) Timing chart according to judgment condition (1-7) The block diagram which shows the electrical structure of the cooling storage which concerns on a determination process and alerting | reporting process

  An embodiment of the present invention will be described with reference to FIGS. In this embodiment, as shown in FIG. 1, a two-door vertical refrigerator is illustrated as the cooling storage 10. As shown in FIGS. 1 and 2, the cooling storage 10 includes a heat-insulating box 12 having a storage chamber 11 and a machine room 14 provided above the box 12. The front surface of the box 12 (the left surface in FIG. 2) is opened, and the opening is partitioned by a partition frame 15 extending in the horizontal direction. Thereby, the storage room 11 has two opening part 11A, 11A arranged in the up-down direction.

  Two doors 16, 16 arranged in the vertical direction are rotatably attached to the box 12, and the opening 11 </ b> A is configured to be opened and closed by the door 16. The box 12 is supported by legs 13 provided at the four corners of the bottom surface. In addition, a shelf board 17 is provided in the storage chamber 11 along the horizontal direction, and stored items stored in the storage room 11 can be placed on the shelf board 17. A cooling device 20 is accommodated in the machine room 14. As shown in FIG. 2, the cooling device 20 is placed on the unit table 23. As shown in FIG. 2, the cooling device 20 includes a condenser 21, a condenser fan 21 </ b> A, and a compressor 22.

  A drain pan 24 that also serves as a cooling duct is disposed on the upper portion of the box 12 so as to be inclined downward toward the rear (right side in FIG. 2). Thereby, a cooler chamber 25 is formed between the unit base 23 and the drain pan 24. In the cooler chamber 25, a cooler 26 is disposed, for example, so as to be attached to the lower surface of the unit table 23. The cooler 26 constitutes a cooling cycle 19 together with the cooling device 20. As shown in FIG. 4, the cooling cycle 19 is mainly configured by circulatingly connecting a compressor 22, a condenser 21, a capillary tube 35, and a cooler 26 through a refrigerant pipe. A refrigerant heavier than air, such as propane or isobutane, is enclosed in the refrigerant pipe. As shown in FIG. 2, an internal fan 27 that is driven by a motor is provided on the front side of the drain pan 24, and a cool air blow-out portion 28 is formed on the rear side of the drain pan 24.

  During the cooling operation, the compressor 22, the internal fan 27, and the condenser fan 21A are driven. By driving the internal fan 27, as shown by an arrow P1 in FIG. 2, the air in the storage chamber 11 is sucked into the cooler chamber 25, and thereafter, heat is exchanged while passing through the cooler 26. The cool air is blown out from the blowing portion 28 into the storage chamber 11 as indicated by an arrow P2. As a result, the storage chamber 11 is cooled by circulating and supplying cool air into the storage chamber 11. In the cooler chamber 25, an internal temperature sensor 29 is disposed above the internal fan 27. The internal temperature sensor 29 can detect the temperature of the air in the storage chamber 11 sucked by the internal fan 27 (the temperature in the storage chamber 11). On the lower surface of the cooler 26, a defrost heater 31 made of, for example, a sheathed heater is provided. The defrost heater 31 is provided to remove frost attached to the cooler 26. In the machine room 14, an air filter 33 is accommodated so as to cover the condenser 21.

  Next, the electrical configuration of the cooling storage 10 will be described. As shown in FIG. 5, the cooling storage 10 includes a control unit 40. The control unit 40 includes a display unit 41, an operation unit 42, a storage unit 43, a first timer 44, a second timer 45, a compressor 22, a motor 21 </ b> B that rotates and drives the condenser fan 21 </ b> A, the internal fan 27, and defrosting. The heater 31 and the internal temperature sensor 29 are electrically connected to each other. For example, the control unit 40 is configured mainly by a CPU, and the storage unit 43 is configured by, for example, a ROM, a RAM, or the like. The control unit 40 executes the computer program stored in the storage unit 43 to control the operation of each device (the compressor 22, the internal fan 27, the defrosting heater 31, etc.) connected to the control unit 40. It is possible to do. The storage unit 43 stores prescribed values and prescribed times in determination conditions (1) to (21) described later. In addition, although the control part 40 is accommodated in the electrical equipment box 18 (refer the broken line of FIG. 1) arrange | positioned in the machine room 14, for example, it is not limited to this. In the present embodiment, for example, a thermistor is used as the temperature sensor, but the present invention is not limited to this.

  The front surface of the machine room 14 is configured by a front panel 14A (see FIG. 1) that can be opened and closed, and the display unit 41 and the operation unit 42 are provided in the operation box 32 shown in FIG. The operation box 32 is disposed on the back side of the front panel 14A, for example. The display unit 41 is configured by a liquid crystal panel, and the operation unit 42 is configured by buttons that can be pressed. The operation box 32 includes a display lamp 34 as shown in FIG. The operator can visually recognize the display unit 41 and the display lamp 34 from the front through a transparent member 46 (glass or the like) provided on the front panel 14A. In addition, the operator can operate the operation unit 42 by opening the front panel 14A. The operator can operate the cooling storage 10 and perform various settings (such as changing the set temperature in the storage) by operating the operation unit 42.

  In this embodiment, the control unit 40 operates after the cooling operation for cooling the interior of the storage chamber 11 by operating the compressor 22, the condenser fan 21A (motor 21B), and the internal fan 27, and the cooling performed after the cooling operation. The defrosting operation for defrosting the frost adhering to the container 26 is alternately executed. In the cooling operation, the control unit 40 stops the compressor 22, the condenser fan 21A, and the internal fan 27 when the temperature detected by the internal temperature sensor 29 becomes lower than the internal set temperature, and the internal temperature sensor When the temperature detected by 29 becomes higher than the internal set temperature, the compressor 22, the condenser fan 21A and the internal fan 27 are driven. Thereby, the temperature in the storage chamber 11 is maintained in the vicinity of the set temperature in the warehouse. The in-compartment set temperature can be set by the operator operating the operation unit 42, and the set in-compartment set temperature is stored in the storage unit 43. In the defrosting operation, the control unit 40 performs off-cycle defrost that stops the compressor 22 and the condenser fan 21 </ b> A and operates the internal fan 27. The off-cycle defrost is performed, for example, every 6 hours, but is not limited thereto. In addition, when the temperature of the cooler 26 measured by the defrosting thermistor 129 (see FIG. 2) provided in the cooler 26 becomes equal to or lower than a specified temperature, the control unit 40 includes the compressor 22 and the condenser fan. 21 A and the internal fan 27 are stopped and the heater defrost which heats the cooler 26 with the defrost heater 31 is performed.

  In this embodiment, as shown in FIG. 2, an air filter 33 is provided so as to cover the condenser 21, and the air filter 33, the condenser 21, the condenser fan 21 </ b> A, and the compressor 22 are arranged in this order from the front side. Has been. In other words, the condenser 21 is disposed between the air filter 33 and the condenser fan 21A. When the condenser fan 21A is operated, the air sucked through the air filter 33 is directed to the condenser 21, and the condenser 21 is operated. Is configured to be cooled. When air passes through the air filter 33, there is a concern that the air filter 33 may be clogged as a result of dust and oil stains adhering to the air filter 33. Therefore, as shown in FIG. 11, the control unit 40 determines that the air filter 33 is clogged when any of determination conditions (1) to (21) described later is satisfied (in FIG. 11). S10) and a notification process (in FIG. 11) for turning on the display lamp 34 (notification unit) provided in the operation box 32 when it is determined that the air filter 33 is clogged by the determination process (Yes in S10). S20). When the display lamp 34 is lit, the user can be notified that the air filter 33 is clogged.

  The control unit 40 can perform the determination process by using the following determination conditions (1) to (21) alone or in combination as appropriate. Next, the determination conditions (1) to (21) and a configuration for performing determination based on each determination condition will be described. The display lamp 34 for performing the notification process is electrically connected to the control unit 40 as shown in FIG. Moreover, the cooling storage 10 is provided with each sensor for making each determination by determination conditions (1)-(21). Specifically, each sensor for performing each determination according to the determination conditions (1) to (21) is a condenser temperature sensor 51, an interior temperature sensor 29, an ambient temperature sensor 30, a door open / close detection sensor 53, a wind speed sensor. 54, air volume sensor 55, motor temperature sensor 56, condenser inlet temperature sensor 57, condenser outlet temperature sensor 58, compressor temperature sensor 59, color sensor 60, light reflectance sensor 61, light transmittance sensor 62, distance sensor 63 , Weight sensor 64, pressure sensor 65, compressor outlet temperature sensor 66, compressor inlet temperature sensor 67, high pressure sensor 68, low pressure sensor 69, cooler outlet temperature sensor 52, refrigerant flow rate sensor 71, refrigerant flow rate sensor 72, And a condenser inlet pressure sensor 73, each of which is electrically connected to the controller 40 as shown in FIG. The function and installation mode of each sensor will be described later.

Judgment condition (1): The state where the measured temperature of the condenser temperature sensor 51 is equal to or higher than a specified value has continued for a specified time.
As shown in FIG. 2, the condenser temperature sensor 51 is attached to an intermediate part of the condenser 21 (an intermediate part of the refrigerant pipe constituting the condenser 21), and can measure the temperature of the condenser 21. It has become. As shown in FIG. 12, when the state where the measured temperature of the condenser temperature sensor 51 is equal to or higher than a specified temperature (for example, 42 ° C.) continues for a specified time T2 (for example, 5 minutes), the control unit 40 operates the display lamp 34. . When the air filter 33 is clogged, cooling of the condenser 21 by the condenser fan 21A is hindered, and the temperature of the condenser 21 increases. For this reason, it can be determined whether the air filter 33 is clogged based on the measured temperature of the condenser temperature sensor 51.

  The motor 21B of the condenser fan 21A is, for example, a DC motor, and the rotation speed can be changed based on a signal (instructed rotation speed) from the control unit 40. In the present embodiment, as shown in FIG. 14, when the temperature of the condenser temperature sensor 51 is equal to or higher than the specified acceleration temperature for a specified time T8 (for example, 10 seconds), the controller 40 controls the motor of the condenser fan 21A. The instruction rotational speed for 21B is increased by one step. Thereby, when the temperature of the condenser temperature sensor 51 rises, the rotation speed of the condenser fan 21 </ b> A increases, and the temperature of the condenser 21 is lowered. Here, when the speed increase regulation temperature is exceeded, the rotation speed of the condenser fan 21A increases and the amount of air passing through the air filter 33 increases, so that the air filter 33 is more easily clogged. For this reason, it is preferable that the specified value in the determination condition (1) is, for example, the specified speed increase temperature (for example, 42 ° C.). In addition, the control part 40 will carry out the instruction | indication rotation speed of the motor 21B of the condenser fan 21A, if the temperature of the condenser temperature sensor 51 continues below the regulation deceleration temperature (for example, 39 degreeC) for the regulation time T9 (for example, 10 seconds). It is the structure which reduces one step.

The following determination conditions (1-1) to (1-7) are determination conditions that increase the accuracy of the clogging determination of the air filter 33 when used in combination with the determination condition (1).
Determination condition (1-1): The temperature measured by the internal temperature sensor 29 is not more than a specified value.
When the temperature of the storage chamber 11 is high, the temperature of the condenser 21 is high even when the air filter 33 is not clogged. For this reason, the situation which misdetermines that it is clogged when the temperature of the store room 11 is high can be suppressed by including the said determination conditions (1-1).
Determination condition (1-2): The difference between the measured temperature of the ambient temperature sensor 30 and the measured temperature of the condenser temperature sensor 51 is not less than a specified value.
As shown by a broken line in FIG. 1, the ambient temperature sensor 30 is accommodated in, for example, an operation box 32 and can detect the temperature in the machine room 14 (the ambient temperature of the condenser 21). . If the ambient temperature of the condenser 21 is high, the temperature of the condenser 21 becomes high even when the air filter 33 is not clogged. For this reason, by including the determination condition (1-2), when the air filter 33 is not clogged and the temperature in the machine chamber 14 is high, it is erroneously determined that the air filter 33 is clogged. The situation can be suppressed. The specified value of the determination condition (1-2) is set at 7 ° C., for example, but is not limited thereto. FIG. 12 illustrates a case where the control unit 40 operates the display lamp 34 when all the determination conditions (1), (1-1), and (1-2) are satisfied. Further, the determination condition (1-2) may be that a state where the difference between the measured temperature of the ambient temperature sensor 30 and the measured temperature of the condenser temperature sensor 51 is equal to or greater than a specified value continues for a specified time.

Determination condition (1-3): The temperature measured by the cooler outlet temperature sensor 52 is not more than a specified value.
As shown in FIG. 4, the cooler outlet temperature sensor 52 is attached to the refrigerant pipe on the outlet side (compressor 22 side) of the cooler 26 and can measure the outlet temperature (refrigerant temperature) of the cooler 26. It has become. When the outlet temperature (coolant temperature) of the cooler 26 increases as the temperature in the storage chamber 11 increases, the temperature of the condenser 21 increases even when the air filter 33 is not clogged. For this reason, when the air filter 33 is not clogged and the outlet temperature of the cooler 26 is high by including the above-described determination condition (1-3), it is erroneously determined that the air filter 33 is clogged. Can be suppressed.

Determination condition (1-4): The door open / close detection sensor 53 detects the closed state of the door 16.
The door opening / closing detection sensor 53 is a door switch provided at the opening edge of the box 12 as shown by a broken line in FIG. 1, and is configured to detect opening / closing of the door 16. A magnet 53 </ b> A is provided at a location corresponding to the door opening / closing detection sensor 53 in the door 16. Thereby, when the door 16 is closed, the door opening / closing detection sensor 53 is turned on. Thereby, the control part 40 can detect that the door 16 is a closed state, when the door opening / closing detection sensor 53 is ON. When the door 16 is open, the temperature of the storage chamber 11 increases, and the temperature of the condenser 21 increases even when the air filter 33 is not clogged. For this reason, by including the determination condition (1-4), it is possible to suppress an erroneous determination that the air filter 33 is clogged when the air filter 33 is not clogged and the door 16 is open. it can.

Determination condition (1-5): The temperature measured by the internal temperature sensor 29 is decreasing.
For example, when the door 16 is opened, the temperature of the storage chamber 11 rises and the condensation temperature rises. Therefore, even if the air filter 33 is not clogged, the temperature of the condenser 21 is high. Become. A state where the temperature measured by the internal temperature sensor 29 is decreasing from the upper limit of the set temperature (for example, the internal set temperature + 1.7 ° C.) to the lower limit of the set temperature (for example, the internal set temperature −2.0 ° C.) (T2 in FIG. 12). Reference) can be considered to be a state in which the interior of the storage chamber 11 is maintained at a relatively appropriate temperature and there is no cause for temperature rise. For this reason, by including the determination condition (1-5), it is erroneously determined that the air filter 33 is clogged when the air filter 33 is not clogged and the temperature of the storage chamber 11 is rising. Can be suppressed.

Determination condition (1-6): The difference between the measured temperature of the condenser temperature sensor 51 when the compressor 22 is operating and the measured temperature of the condenser temperature sensor 51 when the compressor 22 is stopped is defined. Must be greater than or equal to the value.
When the ambient temperature of the condenser 21 is high, the temperature of the condenser 21 becomes high. Further, since there is no exhaust heat from the compressor 22 and the condenser 21 when the compressor 22 is stopped as in off-cycle defrosting, the condenser temperature sensor 51 in a state where the compressor 22 is stopped. The measured temperature can be regarded as the ambient temperature of the condenser 21. Therefore, by including the determination condition (1-6), it is possible to suppress an erroneous determination that the air filter 33 is clogged when the air filter 33 is not clogged and the ambient temperature is high. Further, according to the determination condition (1-6), the ambient temperature can be measured without using the ambient temperature sensor 30, and therefore the ambient temperature sensor 30 may not be provided. Moreover, since the clogging determination of the air filter 33 can be performed based on the ambient temperature in a state where the compressor 22 is stopped, the situation where the ambient temperature is affected by the exhaust heat of the compressor 22 and the condenser 21. It is possible to suppress clogging with higher accuracy.

Determination condition (1-7): the condenser temperature sensor 51 at the time when the measured temperature of the condenser temperature sensor 51 at the time when the compressor 22 stops and the measured temperature of the condenser temperature sensor 51 immediately thereafter become constant. The difference between the measured temperature and the specified temperature is not less than the specified value.
When the ambient temperature of the condenser 21 is high, the temperature of the condenser 21 becomes high. Further, since there is no exhaust heat from the compressor 22 and the condenser 21 when the compressor 22 is stopped, immediately after the compressor 22 stops, the measured temperature of the condenser temperature sensor 51 becomes constant. The temperature measured by the condenser temperature sensor 51 can be regarded as the ambient temperature of the condenser 21. For this reason, by including the determination condition (1-7), it is possible to suppress an erroneous determination that the air filter 33 is clogged when the air filter 33 is not clogged and the ambient temperature is high. And according to the said determination conditions (1-7), since determination processing can be performed when the temperature measured by the condenser temperature sensor 51 immediately after the compressor 22 stops, determination processing is performed. A determination process based on the ambient temperature of the condenser 21 at the time can be performed. The state in which the measured temperature of the condenser temperature sensor 51 is constant is a state in which the measured temperature is the same value for a predetermined time.

  This will be described in detail with reference to FIG. As shown in FIG. 16, at the time of defrosting (see T13 in FIG. 16), since the compressor 22 is stopped, there is no exhaust heat of the condenser 21. For this reason, the measured temperature of the condenser temperature sensor 51 decreases immediately after the compressor 22 stops, reaches the same temperature as the ambient temperature, and thereafter becomes a constant value that is the same as the ambient temperature until the compressor 22 operates. That is, the ambient temperature can be measured by the condenser temperature sensor 51. When the air filter 33 is clogged, the temperature of the condenser temperature sensor 51 gradually increases. Therefore, the measured temperature of the condenser temperature sensor 51 at the time when the compressor 22 stops when the air filter 33 is clogged, and immediately after that, the measured temperature of the condenser temperature sensor 51 is constant (for a specified time). The difference DT2 from the measured temperature of the condenser temperature sensor 51 at the time when the air temperature becomes the measured temperature of the condenser temperature sensor 51 when the compressor 22 stops when the air filter 33 is not clogged, Immediately after that, the difference DT1 from the measured temperature of the condenser temperature sensor 51 at the time when the measured temperature of the condenser temperature sensor 51 becomes constant (for a specified time) becomes larger.

  According to the determination condition (1-7), the control unit 40 can execute the determination process when the measured temperature of the condenser temperature sensor 51 reaches the same temperature as the ambient temperature. For this reason, the clogging of the air filter 33 can be determined based on the ambient temperature at the time when the determination process is executed. If the ambient temperature is measured by the condenser temperature sensor 51 when the compressor 22 is stopped, and then the ambient temperature is compared with the measured temperature of the condenser temperature sensor 51 when the compressor 22 is operating, the ambient temperature is measured. There is a concern that the ambient temperature at the time of comparison and the time of comparison differ, and the clogging determination of the air filter 33 cannot be performed correctly. According to the determination condition (1-7), such a situation can be suppressed. In the above description, the case where the compressor 22 is stopped at the time of defrosting is exemplified, but the determination condition (1-7) is not limited to the time of defrosting, and can be applied when the compressor 22 is stopped. At the time of defrosting, the condenser fan 21A operates, so that the measured temperature of the condenser temperature sensor 51 tends to be the same value as the ambient temperature earlier.

Determination condition (2): One of the determination conditions 2A and 2B based on the rotational speed of the motor 21B that rotates the condenser fan 21A is satisfied.
In the case where the motor 21B is a motor whose rotation speed can be controlled by inverter control or the like and the instruction rotation speed for the motor 21B can be increased (in other words, the instruction rotation speed is less than the upper limit value), the air filter 33 When the temperature of the condenser 21 rises due to clogging, the control unit 40 attempts to lower the temperature of the condenser 21 by increasing the rotational speed of the motor 21B (increasing the indicated rotational speed). For this reason, when the instruction | indication rotation speed with respect to the motor 21B can be increased, the air filter 33 is clogged when the state where the actual rotation speed of the motor 21B has exceeded the specified value continues for a specified time or longer. It can be determined (determination condition 2A).

  Further, when the air filter 33 is clogged, the flow of air passing through the air filter 33 is hindered, resulting in an increase in air resistance when the condenser fan 21A rotates. For this reason, when the indicated rotation speed of the motor 21B is the upper limit value (maximum rotation speed) of the setting range, if the air filter 33 is clogged, the indicated rotation speed of the motor 21B cannot be increased any more, while the condenser Since the air resistance of the fan 21A increases, the actual rotational speed of the motor 21B decreases. For this reason, when the designated rotational speed of the motor 21B is the upper limit value (maximum rotational speed) of the setting range, as shown in FIG. 14, the difference between the designated rotational speed for the motor 21B and the actual rotational speed of the motor 21B is When the state of being equal to or greater than a specified value (for example, 100 rpm) continues for a specified time T10 (for example, 5 minutes), it can be determined that the air filter 33 is clogged (determination condition 2B). Note that the actual rotational speed of the motor 21B can be obtained by an encoder mounted on the motor 21B.

  In the present embodiment, when the state where the temperature of the condenser temperature sensor 51 is equal to or higher than the specified acceleration temperature continues, the indicated rotational speed of the motor 21B increases stepwise, and the indicated rotational speed of the motor 21B is within the set range. The upper limit (maximum speed) is reached. If the motor 21B is a constant speed motor and the air filter 33 is clogged, the actual rotational speed of the motor 21B decreases with respect to the indicated rotational speed of the motor 21B. Based on this, it can be determined that the air filter 33 is clogged.

The following determination conditions (2-1) to (2-4) are conditions for further increasing the accuracy of the clogging determination of the air filter 33 when used in combination with the determination condition (2). By using each of 1) to (2-4) alone, it is possible to determine whether the air filter 33 is clogged.
Determination condition (2-1): The determination condition based on the wind speed of the condenser fan measured by the wind speed sensor is satisfied.
Determination condition (2-2): The determination condition based on the air volume of the condenser fan measured by the air volume sensor is satisfied.

  As shown by a broken line in FIG. 2, for example, the wind speed sensor 54 is provided inside a bracket included in the condenser fan 21 </ b> A, and has a configuration capable of measuring the wind speed of the condenser fan 21 </ b> A. As shown by the broken line in FIG. 2, for example, the air volume sensor 55 is provided inside a bracket provided in the condenser fan 21 </ b> A, and has a configuration capable of measuring the air volume of the condenser fan 21 </ b> A. The installation location of the wind speed sensor 54 and the air volume sensor 55 is not limited to the inside of the bracket, and may be installed between the motor 21B and the compressor 22, for example.

  Since the wind speed and air volume of the condenser fan 21A are basically proportional to the actual rotational speed of the motor 21B, the condenser is considered in the same way as the determination condition (2) based on the actual rotational speed of the motor 21B. The clogging of the air filter 33 can be determined based on the wind speed or air volume of the fan 21A. That is, in the case where the instruction rotational speed for the motor 21B can be increased, it is determined that the air filter 33 is clogged when the wind speed (or air volume) of the condenser fan 21A is equal to or higher than a specified value. it can. Further, when the indicated rotational speed of the motor 21B is the upper limit value (maximum rotational speed) of the setting range, the air filter 33 is clogged when the wind speed (or the air volume) of the condenser fan 21A is equal to or less than a specified value. Can be determined. When the air filter 33 is clogged, even if the actual rotational speed of the motor 21B is constant, the air flow is obstructed, so that it is measured by the wind speed and air volume sensor 55 measured by the wind speed sensor 54. However, even in such a situation, it is determined that the air filter 33 is clogged when the wind speed (or air volume) of the condenser fan 21A is equal to or less than the specified value. can do.

Determination condition (2-3): A state in which the current flowing through the motor 21B for rotating the condenser fan 21A is equal to or greater than a specified value has continued for a specified time.
When the air filter 33 is clogged, cooling of the condenser 21 by the condenser fan 21A is hindered, and the temperature of the condenser 21 increases. At this time, when the motor 21B is a motor whose rotation speed can be controlled by inverter control or the like and the instruction rotation speed for the motor 21B can be increased, the control unit 40 increases the rotation speed of the motor 21B. Thus, the temperature of the condenser 21 is lowered. Since the magnitude of the current flowing through the motor 21B is proportional to the rotational speed of the motor 21B, it can be determined whether or not the air filter 33 is clogged based on the current flowing through the motor 21B.

  On the other hand, when the indicated rotational speed of the motor 21B is the upper limit value (maximum rotational speed) of the setting range (or when the constant speed motor 21B is used), if the air filter 33 is clogged, the condenser fan 21A Since the air resistance during rotation of the motor increases, the current flowing through the motor 21B increases. For this reason, it can be determined whether the air filter 33 is clogged based on the electric current which flows into the motor 21B.

Determination condition (2-4): A state in which the measured temperature of the motor temperature sensor 56 is equal to or higher than a specified value has continued for a specified time.
For example, as shown in FIG. 2, the motor temperature sensor 56 is provided in the case of the motor 21B, and has a configuration capable of measuring the temperature of the motor 21B. When the air filter 33 is clogged, the current flowing through the motor 21B increases as described above. Since the temperature of the motor 21B is proportional to the current of the motor 21B, it can be determined whether the air filter 33 is clogged based on the measured temperature of the motor temperature sensor 56.

Determination condition (3): The integrated value of the rotation speed of the condenser fan 21A (motor 21B) is not less than a specified value.
As the integrated value of the rotation speed of the condenser fan 21A is larger, more air is passing through the air filter 33, so that dust or the like is easily collected in the air filter 33. For this reason, as shown in FIG. 13, it can be determined whether the air filter 33 is clogged based on the integrated value of the rotation speed of the motor 21B (rotation speed of the condenser fan 21A). In addition, the integrated value of the rotation speed of the motor 21B can be obtained by (rotation speed of the motor 21B) × (operation time of the motor 21B). For example, the control unit 40 calculates an integrated value of the number of rotations of the motor 21B with reference to the time when the display lamp 34 is turned off last time.

Judgment condition (4): A state where the difference between the measured temperature of the condenser inlet temperature sensor 57 and the measured temperature of the condenser outlet temperature sensor 58 is not more than a specified value has continued for a specified time.
As shown in FIG. 4, the condenser inlet temperature sensor 57 is provided on the inlet side of the refrigerant pipe constituting the condenser 21, and can measure the inlet temperature of the condenser 21. Further, the condenser outlet temperature sensor 58 is provided on the outlet side of the refrigerant pipe constituting the condenser 21 so that the outlet temperature of the condenser 21 can be measured. When the air filter 33 is clogged, cooling of the condenser 21 by the condenser fan 21 </ b> A is hindered, so that the difference between the inlet temperature of the condenser 21 and the outlet temperature of the condenser 21 is reduced. Therefore, it can be determined whether the air filter 33 is clogged based on the measured temperature of the condenser inlet temperature sensor 57 and the measured temperature of the condenser outlet temperature sensor 58. Further, instead of using the temperature difference between the measured temperature of the condenser inlet temperature sensor 57 and the measured temperature of the condenser outlet temperature sensor 58, the pressure on the inlet side of the refrigerant pipe constituting the condenser 21 and the condenser 21 are configured. You may use the pressure difference with the pressure of the exit side of refrigerant piping to do.

Judgment condition (5): The state where the measured temperature of the compressor temperature sensor 59 is equal to or higher than a specified value has continued for a specified time.
As shown in FIG. 2, the compressor temperature sensor 59 is provided in the case of the compressor 22 and has a configuration capable of measuring the temperature of the compressor 22. The air filter 33 and the compressor 22 are arranged along the blowing direction of the condenser fan 21 </ b> A, and are arranged so that the wind generated by the condenser fan 21 </ b> A passes through the air filter 33 and is sent to the compressor 22. Yes. For this reason, the compressor 22 is air-cooled by the ventilation from the condenser fan 21A. When the air filter 33 is clogged, air blowing to the compressor 22 is hindered, and the temperature of the compressor 22 is likely to rise. Therefore, it can be determined whether or not the air filter 33 is clogged based on the temperature measured by the compressor temperature sensor 59. As shown in FIG. 15, the temperature of the compressor 22 rises while the compressor 22 is operating. When the air filter 33 is clogged, the cooling of the compressor 22 is hindered, so that the temperature increase rate of the compressor 22 during the operation of the compressor 22 increases. For this reason, when the state where the measured temperature of the compressor temperature sensor 59 is equal to or higher than the specified value continues for the specified time T11, the control unit 40 determines that the air filter 33 is clogged and turns on the display lamp 34. Let Note that the temperature of the compressor 22 tends to increase as the ambient temperature increases. For this reason, the storage unit 43 stores, as data, the correspondence between the specified value of the measured temperature of the determination condition (5) obtained in advance by experiment and the ambient temperature, and the control unit 40 stores the determination condition (5 ) Is set as appropriate based on the above data and the measured value of the ambient temperature sensor 30.

Determination condition (6): The continuous operation time of the compressor 22 is not less than a specified value.
In the present embodiment, the compressor 22 and the condenser fan 21 </ b> A are operated or stopped using the internal set temperature as a target value. Specifically, as shown in FIG. 12, the upper limit (set upper temperature limit in FIG. 12) and the lower limit (lower set temperature) are set for the set temperature in the cabinet, and the value of the inner temperature sensor 29 is the upper limit and lower limit. The compressor 22 and the condenser fan 21A are controlled so as to be in between. When the air filter 33 is clogged, the cooling efficiency of the cooling cycle 19 is lowered, so that it is difficult to lower the temperature to the set temperature in the refrigerator, and as a result, the continuous operation time of the cooling cycle 19 (and thus the compressor 22) becomes longer. . For this reason, it can be determined whether the air filter 33 is clogged based on the continuous operation time of the compressor 22. In addition, when ambient temperature is high, since it takes time to reach the set temperature in the refrigerator, the continuous operation time of the compressor 22 increases. For this reason, the control unit 40 determines the specified value of the continuous operation time of the determination condition (6) based on, for example, the measured value of the ambient temperature sensor 30 when the operation of the compressor 22 starts. Moreover, after acquiring the continuous operation time of the compressor 22, the control part 40 determines the regulation value of continuous operation time based on the measured value of the ambient temperature sensor 30, and satisfies the determination condition (6) at that time. It may be determined whether or not.

Determination condition (7): The state in which the rotation speed of the compressor 22 is equal to or greater than a specified value has continued for a specified time.
The compressor 22 is, for example, a system driven by an inverter motor, and is configured to be able to control the rotational speed. The control unit 40 performs control so that the rotational speed of the compressor 22 is gradually reduced as the difference between the set temperature in the store and the temperature measured by the store detection temperature sensor 29 (store temperature) decreases. When the air filter 33 is clogged, the cooling efficiency of the cooling cycle 19 is lowered, so that the internal (inside the storage chamber 11) temperature is difficult to decrease and the internal set temperature is difficult to approach. Tends to be high. For this reason, it can be determined whether the air filter 33 is clogged based on the rotation speed of the compressor 22. Further, if the ambient temperature is high, the internal temperature is difficult to decrease, and therefore the rotational speed of the compressor 22 tends to be high. For this reason, the storage unit 43 stores the correspondence relationship between the prescribed value of the rotational speed of the determination condition (7) and the ambient temperature obtained in advance by experiments as data, and the control unit 40 stores the determination condition (7 ) Is set as appropriate based on the above data and the measured value of the ambient temperature sensor 30.

Determination condition (8): The color of the air filter 33 identified by the color sensor 60 becomes a specified color.
As shown in FIG. 2, a color sensor 60 capable of identifying the color of the air filter 33 is provided on the back side of the front panel 14A. When the air filter 33 is clogged, the color of the air filter 33 changes due to dust or dirt. For this reason, it can be determined that the air filter 33 is clogged when the color of the air filter 33 becomes a specified color. The specified color is appropriately set based on the usage environment of the cooling storage 10. For example, in an environment where oil easily attaches to the air filter 33, it may be determined that the air filter 33 is clogged when the air filter 33 becomes oily color (for example, brown), and dust enters the air filter 33. If the environment is easy to attach, it may be determined that the air filter 33 is clogged when the air filter 33 becomes dusty (for example, white). Alternatively, it may be determined that the air filter 33 is clogged when the air filter 33 loses its original color due to the influence of oil or dust. In addition, as the color sensor 60, for example, an RGB color sensor including three types of photodiodes each having red, green, and blue sensitivities can be used, but is not limited thereto.

Determination condition (9): The light reflectance of the air filter 33 measured by the light reflectance sensor 61 is not more than a specified value.
As shown in FIG. 6, a light reflectance sensor 61 is provided on the front side of the air filter 33, and the light reflectance sensor 61 includes a light projecting unit 61 </ b> A that can emit light toward the air filter 33, and an air filter. And a light receiving unit 61B that receives the light reflected at 33. Thereby, the light reflectance sensor 61 has a configuration capable of measuring the light reflectance of the air filter 33. When the air filter 33 is clogged, the light reflectance of the air filter 33 is lowered. For this reason, it is possible to determine whether the air filter 33 is clogged based on the light reflectance of the air filter 33. As the light reflectance sensor 61, for example, a diffuse reflection type photoelectric sensor can be used, but is not limited thereto.

Determination condition (10): The light transmittance of the air filter 33 measured by the light transmittance sensor 62 is not more than a specified value.
As shown in FIG. 7, the light transmittance sensor 62 includes a light projecting unit 62 </ b> A that can emit light toward the air filter 33, and a light receiving unit 62 </ b> B that receives the light reflected by the air filter 33. The light projecting unit 62A and the light receiving unit 62B are arranged so as to sandwich the air filter 33 from the front and rear. Thereby, the light transmittance sensor 62 is configured to measure the light transmittance of the air filter 33. In the configuration including the light transmittance sensor 62, a space for arranging the light receiving unit 62 </ b> B is provided between the air filter 33 and the condenser 21. When the air filter 33 is clogged, the light transmittance of the air filter 33 decreases. For this reason, it can be determined whether the air filter 33 is clogged based on the light transmittance of the air filter 33. As the light transmittance sensor 62, for example, a light transmission type photoelectric sensor can be used, but is not limited thereto.

Determination condition (11): The distance to the surface of the air filter 33 measured by the distance sensor 63 is equal to or less than a specified value.
As shown in FIG. 8, the distance sensor 63 is arranged on the front side of the air filter 33 and is configured to be able to measure the distance to the surface of the air filter 33. When the air filter 33 is clogged, dust 33B or the like accumulates on the surface of the air filter 33 (the thickness of the air filter 33 increases). The distance of the distance sensor 63 becomes small. For this reason, it is possible to determine whether or not the air filter 33 is clogged based on the distance measured by the distance sensor 63. As the distance sensor 63, for example, a laser sensor can be used.

Determination condition (12): The weight of the air filter 33 measured by the weight sensor 64 is not less than a specified value.
As shown in FIG. 9, a weight sensor 64 capable of measuring the weight of the air filter 33 is provided on the mounting surface of the air filter 33 in the unit base 23. When the air filter 33 is clogged, dust or the like accumulates on the surface of the air filter 33, so that the weight of the air filter 33 increases. Therefore, it can be determined whether the air filter 33 is clogged based on the weight of the air filter 33 measured by the weight sensor 64.

Determination condition (13): The pressure in the space S1 disposed between the condenser 21 and the condenser fan 21A measured by the pressure sensor 65 is equal to or less than a specified value.
As shown in FIG. 6, a pressure sensor 65 capable of measuring pressure is arranged in a space S1 (for example, in the bell mouth of the condenser fan 21A) arranged between the condenser 21 and the condenser fan 21A. . When the air filter 33 is clogged, the amount of air sucked into the condenser 21 through the air filter 33 decreases. As a result, the pressure (static pressure) in the space S1 disposed between the condenser 21 and the condenser fan 21A decreases. For this reason, it is possible to determine whether or not the air filter 33 is clogged based on the pressure of the space S1 measured by the pressure sensor 65.

Determination condition (14): The outlet temperature of the compressor 22 measured by the compressor outlet temperature sensor 66 is not less than a specified value.
As shown in FIG. 4, a refrigerant outlet temperature sensor 66 capable of measuring the outlet temperature of the compressor 22 is provided in the refrigerant pipe on the outlet side of the compressor 22. When the air filter 33 is clogged, the outlet temperature of the compressor 22 rises. Based on this, it can be determined whether or not the air filter 33 is clogged.
Determination condition (15): The inlet temperature of the compressor 22 measured by the compressor inlet temperature sensor 67 is equal to or higher than a specified value.
As shown in FIG. 4, the compressor 22 is provided with a compressor inlet temperature sensor 67 capable of measuring the inlet temperature of the compressor 22. When the air filter 33 is clogged, the inlet temperature of the compressor 22 rises, and based on this, it can be determined whether or not the air filter 33 is clogged.

Judgment condition (16): The high pressure measured by the high pressure sensor 68 is not less than a specified value.
Judgment condition (17): The low-pressure pressure measured by the low-pressure sensor 69 is not less than a specified value.
As shown in FIG. 4, the refrigerant pipe on the outlet side of the compressor 22 is provided with a high pressure sensor 68 capable of measuring the high pressure of the cooling cycle 19. A refrigerant pipe on the inlet side of the compressor 22 is provided with a low pressure sensor 69 that can measure the low pressure of the cooling cycle 19. When the air filter 33 is clogged, the high pressure and the low pressure increase, so it can be determined whether the air filter 33 is clogged based on the high pressure or the low pressure.

Determination condition (18): The degree of superheat of the refrigerant in the cooler 26 is not less than a specified value.
When the air filter 33 is clogged, cooling of the condenser 21 by the condenser fan 21 </ b> A is hindered, so that the temperature of the refrigerant from the condenser 21 toward the cooler 26 increases and the degree of superheat in the cooler 26 increases. For this reason, it can be determined whether the air filter 33 is clogged based on the degree of superheat. The degree of superheat can be calculated from the difference between the measured temperatures of the cooler outlet temperature sensor 52 and the cooler inlet temperature sensor 70 shown in FIG. As shown in FIG. 4, the cooler inlet temperature sensor 70 is attached to the refrigerant pipe on the inlet side of the cooler 26 and is configured to measure the inlet temperature (refrigerant temperature) of the cooler 26. . Alternatively, the degree of superheat may be calculated using the refrigerant saturation temperature at the pressure measured by the low-pressure sensor 69 instead of using the temperature measured by the cooler inlet temperature sensor 70.

Determination condition (19): The circulation amount of the refrigerant measured by the refrigerant flow rate sensor 71 is equal to or greater than a specified value.
Determination condition (20): The refrigerant flow rate measured by the refrigerant flow rate sensor 72 is not less than a specified value.
Determination condition (21): The pressure loss of the refrigerant in the cooling cycle 19 is equal to or greater than a specified value.
As shown in FIG. 4, the refrigerant pipe constituting the cooling cycle 19 is provided with a refrigerant flow sensor 71 capable of measuring the refrigerant circulation amount in the cooling cycle 19. In addition, a refrigerant flow rate sensor 72 capable of measuring the flow rate of the refrigerant in the cooling cycle 19 is provided in the refrigerant pipe constituting the cooling cycle 19. When the air filter 33 is clogged, the circulation amount of the refrigerant increases. For this reason, it can be determined whether the air filter 33 is clogged based on the circulation amount of the refrigerant. Further, when the circulation amount of the refrigerant increases, the flow rate of the refrigerant increases. For this reason, it can be determined whether the air filter is clogged based on the flow rate of the refrigerant. Further, when the flow rate of the refrigerant increases, the pressure loss of the refrigerant in the refrigerant pipe increases. For this reason, it can be determined whether the air filter 33 is clogged based on the pressure loss of the refrigerant. The pressure loss of the refrigerant is a pressure difference between two points on the low pressure side (or between two points on the high pressure side) in the refrigerant pipe constituting the cooling cycle 19. For example, as shown in FIG. Can be obtained by calculating the difference between the measured value of the condenser inlet pressure sensor 73 and the measured value of the high-pressure sensor 68 provided on the inlet side of the refrigerant pipe constituting.

  Next, the operation of the control unit 40 related to the first timer 44 and the second timer 45 will be described. As shown in FIG. 3, one of the buttons constituting the operation unit 42 of the operation box 32 is a reset button 42A (operation stop unit) for ending the notification process. When the reset button 42A is pressed by the user (see P3 in FIG. 12), the control unit 40 turns off the display lamp 34 (stops the operation of the notification unit), as shown in FIG. And the second timer 45 is reset.

  Further, as shown in FIG. 12, the control unit 40 does not execute the notification process for a specified time T1 (for example, one week) after the display lamp 34 is turned off. Specifically, the first timer 44 is set to be turned on when the specified time T1 has elapsed. The control unit 40 turns on the display lamp 34 when the first timer 44 is on and when any of the determination conditions (1) to (21) is satisfied. When the display lamp 34 is turned off, there is a high possibility that the air filter 33 has been cleaned by the user. For this reason, it can be considered that the possibility that the air filter 33 is clogged is low during the specified time T1. For this reason, during the specified time T1, by not performing the notification process, it is possible to suppress a situation in which it is erroneously determined that the air filter 33 is clogged and the notification process is performed. Also, as shown in FIG. 12, the count of the first timer 44 starts at the same time as the power supply of the cooling storage 10 is turned on. For this reason, the control part 40 does not perform an alerting | reporting process for the regulation time T1 after the power supply of the cooling storage 10 is turned ON.

  Further, as shown in FIG. 12, the control unit 40 turns off the display lamp 34 after a specified time T4 (for example, 24 hours) has elapsed since the display lamp 34 was turned on (after the notification process was executed). This eliminates the need for the user to press the reset button 42A to turn off the display lamp 34. Further, as shown in FIG. 12, the control unit 40 operates the display lamp 34 after a specified time T3 (for example, two weeks) has elapsed since the display lamp 34 was turned off. Specifically, the second timer 45 is turned on when a specified time T3 has elapsed, and is reset when the display lamp 34 is turned off. When the second timer 45 is turned on, the control unit 40 turns on the display lamp 34 regardless of the determination condition. By periodically operating the display lamp 34, the user can be regularly prompted to clean the air filter 33.

  Further, as shown in FIG. 10, a magnet 33A is embedded in the air filter 33 (more specifically, a skeleton portion that supports the mesh portion of the air filter), and the unit base 23 detects the approach of the magnet 33A. A proximity sensor 23A is provided. The proximity sensor 23A is electrically connected to the control unit 40, and can detect that the air filter 33 is attached to cover the condenser 21 by the proximity sensor 23A (air filter attachment detection sensor). . As shown in FIG. 12, the controller 40 resets the first timer 44 and the second timer 45 when the proximity sensor 23A is turned on. Thereby, the control unit 40 is configured to turn on the display lamp 34 after the lapse of the specified time T3 after the proximity sensor 23A is turned on (after the air filter attachment detection sensor detects that the air filter is attached). It has become. When the air filter 33 is attached, there is a high possibility that the air filter 33 is cleaned by the user. For this reason, the cleaning of the air filter 33 is used after the elapse of the specified time T3 from the previous cleaning of the air filter 33 by turning on the display lamp 34 after the elapse of the specified time T3 after detecting that the air filter 33 is attached. Can be encouraged.

<Other embodiments>
The present invention is not limited to the embodiments described with reference to the above description and drawings. For example, the following embodiments are also included in the technical scope of the present invention.
(1) Each specified value and each specified time in the determination conditions (1) to (21), (1-1) to (1-7), and (2-1) to (2-4) can be set as appropriate. It is. In addition, each regulation value and each regulation time in the determination conditions (1) to (21), (1-1) to (1-7), and (2-1) to (2-4) are, for example, an air filter The cooling storage 10 can be operated on a trial basis in a state where 33 is clogged and a state where it is not clogged, and the determination can be made based on the result.
(2) In the said embodiment, although the display lamp 34 was illustrated as an alerting | reporting part, it is not limited to this. The notification unit may be configured to notify the clogging of the air filter 33 by generating a sound or displaying characters on the display unit 41.
(3) The control part 40 should just be the structure which performs a determination process using at least 1 determination condition among the said determination conditions (1)-(21), and the cooling storage 10 is at least 1 determination condition. It is also possible to provide only the configuration necessary for executing
(4) The cooling storage may include a plurality of cooling cycles and air filters. In such a case, it may be determined that the air filter is clogged when the determination condition is satisfied in all cooling cycles.

DESCRIPTION OF SYMBOLS 10 ... Cooling storage, 11 ... Storage room, 12 ... Box body, 14 ... Machine room, 16 ... Door, 19 ... Cooling cycle, 21 ... Condenser, 21A ... Condenser fan, 21B ... Motor, 22 ... Compressor, 23A ... proximity sensor (air filter attachment detection sensor), 26 ... cooler, 29 ... internal temperature sensor, 30 ... ambient temperature sensor, 33 ... air filter, 34 ... display lamp (notification part), 40 ... control part, 42A ... Reset button (operation stop unit), 51 ... condenser temperature sensor, 52 ... cooler outlet temperature sensor, 53 ... door opening / closing detection sensor, 54 ... air speed sensor, 55 ... air volume sensor, 56 ... motor temperature sensor, 57 ... condenser Inlet temperature sensor, 58 ... Condenser outlet temperature sensor, 59 ... Compressor temperature sensor, 60 ... Color sensor, 61 ... Light reflectance sensor, 62 ... Light transmittance sensor, 63 ... Distance sensor, 64 ... Weight Capacitors, 65 ... pressure sensor, 66 ... compressor exit temperature sensor, 67 ... compressor inlet temperature sensor, 68 ... high-pressure sensor, 69 ... low pressure sensor, 71 ... refrigerant flow sensor, 72 ... refrigerant flow sensors, S1 ... space

Claims (38)

A box having a storage room in which stored items are arranged;
A machine room,
A cooler that constitutes a cooling cycle and is capable of cooling the storage chamber;
A condenser housed in the machine room and constituting the cooling cycle;
A compressor housed in the machine room and constituting the cooling cycle;
An air filter housed in the machine room and covering the condenser;
A condenser fan housed in the machine room for cooling the condenser;
A control unit;
A notification unit capable of notifying that the air filter is clogged, and
The controller is
A determination process for determining that the air filter is clogged when a predetermined determination condition is satisfied;
A cooling storage that executes a notification process for operating the notification unit when it is determined by the determination process that the air filter is clogged. A condenser temperature sensor capable of measuring the temperature of the condenser;
The determination condition is as follows:
The cooling storage according to claim 1, wherein the state in which the measured temperature of the condenser temperature sensor is equal to or higher than a specified value includes that the specified temperature has continued for a specified time. An internal temperature sensor capable of measuring the temperature of the storage room;
The determination condition is as follows:
The cooling storage according to claim 2, wherein the temperature measured by the internal temperature sensor is not more than a specified value. An ambient temperature sensor capable of measuring the ambient temperature of the condenser;
The determination condition is as follows:
The difference between the measured temperature of the condenser temperature sensor and the measured temperature of the ambient temperature sensor is not less than a specified value, or includes a state in which the difference is not less than a specified value has continued for a specified time. Cooling storage. A cooler outlet temperature sensor capable of measuring the outlet temperature of the cooler;
The determination condition is as follows:
The cooling storehouse as described in any one of Claims 2-4 including that the measured temperature of the said cooler exit temperature sensor is below a regulation value. A door provided in the box and capable of opening and closing the storage chamber;
A door opening / closing detection sensor capable of detecting opening and closing of the door,
The determination condition is as follows:
The cooling storage according to any one of claims 2 to 5, wherein the door opening / closing detection sensor detects that the door is closed. An internal temperature sensor capable of measuring the temperature of the storage room;
The determination condition is as follows:
The cooling storage according to any one of claims 2 to 6, including that the temperature measured by the internal temperature sensor is decreasing. The determination condition is as follows:
The difference between the measured temperature of the condenser temperature sensor in a state where the compressor is operating and the measured temperature of the condenser temperature sensor in a state where the compressor is stopped includes a specified value or more. The cooling storage as described in any one of Claims 2-7. The determination condition is as follows:
A temperature measured by the condenser temperature sensor at the time when the compressor is stopped;
The difference from the measured temperature of the condenser temperature sensor at the time when the measured temperature of the condenser temperature sensor becomes constant immediately after that is not less than a specified value. The cooling storage according to item. The determination condition is as follows:
The cooling storage as described in any one of Claims 1-9 including the determination conditions based on the rotation speed of the motor which rotationally drives the said condenser fan. The determination condition is as follows:
The cooling storage as described in any one of Claims 1-10 including that the state which the electric current which flows into the motor which rotationally drives the said condenser fan is more than a regulation value continued for the regulation time. A wind speed sensor capable of measuring the wind speed of the condenser fan;
The determination condition is as follows:
The cooling storage as described in any one of Claims 1-11 including the determination conditions based on the wind speed measured by the said wind speed sensor. An air volume sensor capable of measuring the air volume of the condenser fan;
The determination condition is as follows:
The cooling storage as described in any one of Claims 1-12 including the determination conditions based on the airflow measured by the said airflow sensor. A motor temperature sensor capable of measuring the temperature of a motor that rotationally drives the condenser fan;
The determination condition is as follows:
The cooling storage according to any one of claims 1 to 13, including a state in which the measured temperature of the motor temperature sensor is equal to or higher than a specified value continues for a specified time. The determination condition is as follows:
The cooling storage as described in any one of Claims 1-14 including that the integrated value of the rotation speed of the said condenser fan is more than a regulation value. A condenser inlet temperature sensor capable of measuring the inlet temperature of the condenser;
A condenser outlet temperature sensor capable of measuring the outlet temperature of the condenser;
The determination condition is as follows:
The state where the difference between the measured temperature of the condenser inlet temperature sensor and the measured temperature of the condenser outlet temperature sensor is equal to or less than a specified value has continued for a specified time. Refrigerated storage as described. The air filter and the compressor are arranged along a blowing direction of the condenser fan,
A compressor temperature sensor capable of measuring the temperature of the compressor;
The determination condition is as follows:
The cooling storage according to any one of claims 1 to 16, including a state in which a state where the measured temperature of the compressor temperature sensor is equal to or higher than a specified value continues for a specified time. The determination condition is as follows:
The cooling storage according to any one of claims 1 to 17, wherein the continuous operation time of the compressor is not less than a specified value. The determination condition is as follows:
The cooling storage according to any one of claims 1 to 18, including a state in which a state in which the rotation speed of the compressor is equal to or greater than a specified value has continued for a specified time. A color sensor capable of identifying the color of the air filter;
The cooling storage according to any one of claims 1 to 19, wherein the determination condition includes that a color of the air filter identified by the color sensor becomes a specified color. A light reflectance sensor capable of measuring the light reflectance of the air filter;
The determination condition is as follows:
The cooling storage according to any one of claims 1 to 20, wherein a light reflectance of the air filter measured by the light reflectance sensor is equal to or less than a specified value. A light transmittance sensor capable of measuring the light transmittance of the air filter;
The determination condition is as follows:
The cooling storage according to any one of claims 1 to 20, wherein the light transmittance of the air filter measured by the light transmittance sensor is equal to or less than a specified value. A distance sensor capable of measuring the distance to the surface of the air filter;
The determination condition is as follows:
The cooling storage according to any one of claims 1 to 22, wherein a distance to the surface of the air filter measured by the distance sensor is equal to or less than a specified value. A weight sensor capable of measuring the weight of the air filter;
The determination condition is as follows:
The cooling storage according to any one of claims 1 to 23, wherein the weight of the air filter measured by the weight sensor is equal to or greater than a specified value. The condenser is disposed between the air filter and the condenser fan;
The condenser fan is configured to direct air sucked through the air filter to the condenser,
A pressure sensor capable of measuring the pressure in the space between the condenser and the condenser fan;
The determination condition is as follows:
The cooling storage according to any one of claims 1 to 24, wherein the pressure of the space measured by the pressure sensor is equal to or less than a specified value. A compressor outlet temperature sensor capable of measuring the outlet temperature of the compressor;
The determination condition is as follows:
The cooling storage according to any one of claims 1 to 25, wherein an outlet temperature of the compressor measured by the compressor outlet temperature sensor is equal to or higher than a specified value. A compressor inlet temperature sensor capable of measuring the inlet temperature of the compressor;
The determination condition is as follows:
The cooling storage according to any one of claims 1 to 26, wherein an inlet temperature of the compressor measured by the compressor inlet temperature sensor is equal to or higher than a specified value. A high pressure sensor capable of measuring the high pressure of the cooling cycle;
The determination condition is as follows:
The cold storage according to any one of claims 1 to 27, wherein the high pressure measured by the high pressure sensor is equal to or higher than a specified value. A low pressure sensor capable of measuring the low pressure of the cooling cycle,
The determination condition is as follows:
The cold storage according to any one of claims 1 to 28, wherein the low pressure measured by the low pressure sensor is equal to or higher than a specified value. The determination condition is as follows:
30. The cooling storage according to any one of claims 1 to 29, wherein the degree of superheat of the refrigerant in the cooler is equal to or greater than a specified value. A refrigerant flow rate sensor capable of measuring the circulation amount of the refrigerant in the cooling cycle;
The determination condition is as follows:
The cooling storage according to any one of claims 1 to 30, wherein the circulation amount of the refrigerant measured by the refrigerant flow sensor becomes equal to or more than a specified value. A refrigerant flow rate sensor capable of measuring the flow rate of the refrigerant in the cooling cycle;
The determination condition is as follows:
The cooling storage according to any one of claims 1 to 31, wherein the refrigerant flow rate measured by the refrigerant flow rate sensor is equal to or higher than a specified value. The determination condition is as follows:
The cooling storage according to any one of claims 1 to 32, wherein the pressure loss of the refrigerant in the cooling cycle includes a specified value or more.   The cooling storage according to any one of claims 1 to 33, further comprising an operation stop unit capable of stopping the operation of the notification unit. The controller is
The cooling storage according to claim 34, wherein the notification process is not executed for a specified time after the operation of the notification unit is stopped by the operation stop unit. The controller is
36. The cooling storage according to claim 34 or claim 35, wherein the notification unit is operated after a specified time has elapsed since the operation of the notification unit was stopped. The controller is
The cooling storage according to any one of claims 1 to 36, wherein an operation of the notification unit is stopped after a specified time has elapsed since the notification process was executed. An air filter attachment detection sensor capable of detecting that the air filter is attached so as to cover the condenser;
The controller is
The cooling storage according to any one of claims 1 to 37, wherein the notification unit is operated after a predetermined time has elapsed since the air filter attachment detection sensor detected that the air filter was attached.

Images