JP2020156912A - Refrigerated showcase and operation method of refrigerated showcase - Google Patents

Abstract

To provide a refrigerated showcase capable of suppressing an increase in a power consumption of a refrigerant supply part, and operation method of the refrigerated showcase.SOLUTION: A refrigerated showcase 1 according to the present invention, a determination criterion time tx is set based on a continuous operation time from driving a refrigerant supply part 13b to stopping it. When the determination criterion time tx elapses from driving the refrigerant supply part 13b without stopping it, it is determined whether or not a temperature in a showroom 2 is equal to or lower than a determination criterion temperature θx that is lower than a setup upper limit temperature θa and higher than a setup lower limit temperature θb. When the temperature in the showroom 2 is equal to or lower than the determination criterion temperature θx, the refrigerant supply part 13b is made to stop.SELECTED DRAWING: Figure 4

Description

The present invention relates to a refrigerated showcase and a method of operating a refrigerated showcase in which products are displayed while being cooled by cold air.

Conventionally, a refrigerated showcase in which products are displayed while being cooled by cold air has been known (see, for example, Patent Document 1). In this refrigerated showcase, a fan generally sucks cold air (air) from the display room and sends it to a cooler. The cold air sent to the cooler is cooled and returned to the display room. In this way, the cold air (air) is circulated while being cooled to cool the displayed products.

The temperature in the display room is measured by a temperature sensor. Based on the measured temperature, the refrigerator (refrigerant supply unit) that supplies the refrigerant to the cooler is controlled to maintain the temperature in the display chamber within a desired temperature range. More specifically, the refrigerator is driven when the temperature in the display chamber is equal to or higher than the set upper limit temperature, and the refrigerator is stopped when the temperature in the display chamber is equal to or lower than the set lower limit temperature. That is, when the temperature in the display chamber rises due to the shutdown of the refrigerator and reaches the set upper limit temperature, the refrigerator is driven to cool the cold air. On the other hand, when the temperature in the display room drops due to the driving of the refrigerator and reaches the set lower limit temperature, the refrigerator is stopped. The temperature in the display chamber is maintained in a desired temperature range by repeatedly driving and stopping the refrigerator in such a cycle.

Japanese Unexamined Patent Publication No. 2011-24771

However, even if the refrigerator is continuously driven, the temperature in the display chamber cannot be lowered to the set lower limit temperature, and the continuous driving time of the refrigerator may be lengthened. For example, if the outside temperature is high, or if the sliding door is open for a long time in a face-to-face refrigerated showcase, the air curtain will be disturbed by the influence of the wind from the outside in the open showcase. If so, the refrigerator may continue to be driven for a long time. In this case, there is a problem that the power consumption of the refrigerator increases.

The present invention has been made in consideration of such a point, and provides a refrigerated showcase and a method of operating a refrigerated showcase capable of suppressing an increase in power consumption of a refrigerant supply unit. The purpose.

The present invention
A refrigerated showcase that displays products while cooling them with cold air.
The display room where the products are displayed and
A circulation flow forming portion that circulates the cold air in the display chamber,
A cooler that cools the cold air with a refrigerant,
A refrigerant supply unit that supplies the refrigerant to the cooler,
A temperature measuring instrument that measures the temperature in the display room,
The refrigerant supply unit drives the refrigerant supply unit when the temperature in the display chamber is equal to or higher than the set upper limit temperature, and stops the refrigerant supply unit when the temperature in the display chamber is equal to or lower than the set lower limit temperature. With a control unit to control
The control unit sets a determination reference time based on the continuous drive time from driving the refrigerant supply unit to stopping the refrigerant supply unit.
When the determination reference time elapses without stopping after driving the refrigerant supply unit, the control unit has a temperature in the display chamber lower than the set upper limit temperature and higher than the set lower limit temperature. A refrigerating showcase that determines whether or not the temperature is below the determination reference temperature and stops the refrigerant supply unit when the temperature in the display chamber is below the determination reference temperature.
I will provide a.

In the refrigerated showcase mentioned above
The control unit calculates a drive reference time based on the plurality of continuous drive times, and sets the determination reference time to be longer than the drive reference time.
You may do so.

In the refrigerated showcase mentioned above
The drive reference time is an average value of a plurality of the continuous drive times.
You may do so.

In the refrigerated showcase mentioned above
When the determination reference time is tx, the drive reference time is ts, and tx = ts × α, α is 1.2 to 2.0.
You may do so.

In the refrigerated showcase mentioned above
The determination reference temperature is lower than the intermediate value between the set upper limit temperature and the set lower limit temperature.
You may do so.

In the refrigerated showcase mentioned above
The period from driving the refrigerant supply unit to being restarted after one stop is defined as one cycle.
When a plurality of the cycles are performed, the control unit determines that the temperature in the display chamber is the determination reference temperature for the cycle performed after the cycle corresponding to the continuous drive time for setting the determination reference time. Judge whether or not it is
You may do so.

In the refrigerated showcase mentioned above
The control unit calculates a drive reference time based on a plurality of continuous drive times including the continuous drive time in the cycle immediately before the cycle for determining whether or not the temperature is equal to or lower than the determination reference temperature, and the determination is made. Set the reference time to be longer than the drive reference time,
You may do so.

In addition, the present invention
It is a method of operating a refrigerated showcase that displays products while cooling them with cold air.
A process of driving a refrigerant supply unit that supplies a refrigerant to a cooler that cools cold air when the temperature in the display room where the products are displayed rises to the set upper limit temperature.
A step of stopping the refrigerant supply unit when the temperature in the display chamber drops to the set lower limit temperature, and
A step of setting a determination reference time based on a continuous driving time from driving the refrigerant supply unit to stopping the refrigerant supply unit, and
When the determination reference time elapses without stopping after driving the refrigerant supply unit, the temperature in the display chamber is lower than the set upper limit temperature and higher than the set lower limit temperature below the determination reference temperature. A method of operating a refrigerated showcase, comprising a step of determining whether or not the refrigerant is present and stopping the refrigerant supply unit when the temperature in the display chamber is equal to or lower than the determination reference temperature.
I will provide a.

According to the present invention, it is possible to suppress an increase in the power consumption of the refrigerant supply unit.

FIG. 1 is a perspective view showing an example of the overall configuration of the refrigerated showcase according to the present embodiment. FIG. 2 is a side sectional view showing the refrigerated showcase of FIG. FIG. 3 is a graph showing the temperature characteristics in the display room in a general refrigerated showcase. FIG. 4 is a graph showing an example of the temperature characteristics in the display room in the refrigerated showcase according to the present embodiment. FIG. 5 is a graph showing another example of the temperature characteristics of FIG. FIG. 6 is a side sectional view showing another example of the refrigerated showcase according to the present embodiment.

Hereinafter, an embodiment of the present invention will be described with reference to the drawings. In the drawings attached to the present specification, the scale, aspect ratio, etc. are appropriately changed from those of the actual product and exaggerated for the convenience of illustration and comprehension.

In the present embodiment, as an example of a refrigerated showcase in which products are displayed while being cooled by cold air, a face-to-face refrigerated showcase (sometimes referred to as a closed refrigerated showcase) will be described below. ..

As shown in FIGS. 1 and 2, the refrigerated showcase 1 in the present embodiment has a display room 2 in which products are displayed, a base 3 provided below the display room 2, and a front of the display room 2. The front portion 4 provided in the display chamber 2, the ceiling portion 5 provided above the display chamber 2, the side portions 6 provided on both sides of the display chamber 2, and the sliding door 7 provided behind the display chamber 2. , Is equipped. The display room 2 is defined and sealed by the base 3, the ceiling 5, the front 4, the side 6, and the sliding door 7.

The front surface portion 4 is capable of seeing through the products in the display chamber 2, and is made of, for example, a transparent glass plate or a transparent resin plate. The ceiling portion 5 and the side surface portion 6 may also be capable of seeing through the products in the display room 2, but may also be translucent or opaque. The sliding door 7 is configured to be openable and closable. The sliding door 7 may have any configuration as long as it is possible to display the products in the display room 2 and take out the products from the display room 2. FIG. 1 shows an example in which the sliding door 7 is composed of a pair of sliding door panels.

On the upper surface of the base 3, a plurality of display chamber bottom plates 8 on which products are placed are provided. Further, one or more display shelves 9 may be provided in the display room 2. The display shelf 9 may be supported by a plurality of columns 10 provided behind the display room 2. Such columns 10 may be arranged behind the display chamber 2 on both sides, or may be arranged behind and in the center of the display chamber 2, and the arrangement of the columns 10 is arbitrary. A lighting device 11 is provided on the lower surface of the front end portion of the display shelf 9, and the products displayed below the lighting device 11 are illuminated by the lighting device 11. The lighting device 11 may also be provided below the ceiling portion 5 described above.

As shown in FIG. 2, the refrigerating showcase 1 according to the present embodiment includes a fan 12 (circulation flow forming unit) for circulating cold air (air) in the display chamber 2 and a cooling device 13 for cooling the cold air. Further prepared. These fans 12 and the cooling device 13 are arranged in the base 3. The cooling device 13 includes a cooler 13a that cools the cold air with a refrigerant, and a refrigerator 13b (refrigerant supply unit) that supplies the refrigerant to the cooler 13a. The cooler 13a may include a plurality of pipes through which the refrigerant flows. Each pipe may be provided with fins for increasing the contact area with cold air. When the refrigerator 13b is driven, the refrigerant is cooled, and the heat is discharged to the outside accordingly. The cooled refrigerant flows through the pipe of the cooler 13a and exchanges heat with the cold air flowing through the cold air flow path 16 described later via the pipe and fins to cool the cold air. The refrigerant that has exchanged heat with the cold air is returned to the refrigerator 13b and cooled again in the refrigerator 13b. In this way, the refrigerant alternately communicates with the cooler 13a and the refrigerator 13b and circulates.

The base 3 has a suction port 14 that sucks cold air from the display chamber 2, a supply port 15 that supplies (returns) the sucked cold air to the display chamber 2, and a cold air flow path that communicates the suction port 14 and the supply port 15. 16 and. Of these, the fan 12 and the cooler 13a are arranged in the cold air flow path 16. The fan 12 is arranged on the side (upstream side) of the suction port 14 with respect to the cooler 13a. With such a configuration, the cold air in the display chamber 2 is sucked into the cold air flow path 16 from the suction port 14 and flows to the supply port 15 through the fan 12 and the cooler 13a. During this time, the cold air is cooled by the cooler 13a. The cold air that has reached the supply port 15 is discharged from the cold air flow path 16 and supplied into the display chamber 2. In this way, the cold air cooled by the cooler 13a is supplied into the display chamber 2, and the product is cooled while the cold air in the display chamber 2 circulates. The refrigerator 13b is arranged below the cold air flow path 16 in the base 3.

A drainage channel 17 is provided in the cold air flow path 16. The drainage channel 17 is arranged on the side (downstream side) of the supply port 15 with respect to the cooler 13a. The condensed water generated when the cold air is cooled by the cooler 13a is discharged from the drainage channel 17.

Further, the refrigerating showcase 1 according to the present embodiment further includes a temperature sensor 18 (temperature measuring instrument) for measuring the temperature in the display chamber 2 and a control unit 19 for controlling the refrigerator 13b of the cooling device 13. ing.

The temperature sensor 18 can be arranged at an arbitrary position as long as the temperature inside the display chamber 2 can be measured. For example, as shown in FIGS. 1 and 2, the temperature sensor 18 may be the lower surface of the display shelf 9 arranged on the lower side and may be arranged on the rear side of the display shelf 9. In this case, the temperature sensor 18 can be arranged close to the supply port 15, and the temperature sensor 18 can be exposed to the cold air flowing into the display room 2 from the supply port 15. In this case, it can be said that the temperature sensor 18 measures the temperature of the cold air that has flowed into the display chamber 2. However, the arrangement of the temperature sensor 18 is not limited to this, and is arbitrary as long as the temperature in the display chamber 2 can be measured as described later. An example in which the temperature sensor 18 is used is shown as an example of the temperature measuring instrument, but the present invention is not limited to this as long as the temperature in the display chamber 2 can be measured. The temperature sensor 18 is connected to the control unit 19, and the temperature measurement value in the display room 2 measured by the temperature sensor 18 is transmitted as a signal to the control unit 19.

The control unit 19 receives a signal indicating the temperature measurement value transmitted from the temperature sensor 18, and controls the refrigerator 13b based on the temperature measurement value in the display chamber 2. More specifically, the control unit 19 drives (ON) the refrigerator 13b when the temperature in the display chamber 2 is equal to or higher than the set upper limit temperature θa, and the temperature in the display chamber 2 is equal to or lower than the set lower limit temperature θb. The refrigerator 13b is controlled so as to stop (OFF) the refrigerator 13b in a certain case. During the operation of the refrigerating showcase 1, for example, when the sliding door 7 is closed, the refrigerator 13b is repeatedly driven and stopped in the cycle shown in FIG. That is, when the temperature in the display chamber 2 rises due to the shutdown of the refrigerator 13b and reaches the set upper limit temperature θa, the refrigerator 13b is driven to cool the cold air. On the other hand, when the temperature in the display chamber 2 is lowered by driving the refrigerator 13b and reaches the set lower limit temperature θb, the refrigerator 13b is stopped. In this way, the temperature in the display chamber 2 is maintained in the range from the set lower limit temperature θb to the set upper limit temperature θa. The control unit 19 may be configured by, for example, a microcomputer.

When the sliding door 7 is closed, the drive and stop of the refrigerator 13b are repeated in a similar cycle as shown in FIG. However, when the sliding door 7 is open or when the outside air temperature is high, such a cycle may be disrupted and the continuous driving time of the refrigerator 13b may be lengthened. The control unit 19 according to the present embodiment has a configuration for dealing with such a case.

The control unit 19 according to the present embodiment sets a determination reference time based on the continuous drive time from driving the refrigerator 13b to stopping, and stops driving the refrigerator 13b based on the determination reference time. It is configured to determine whether or not to do so.

More specifically, the control unit 19 calculates the drive reference time based on a plurality of continuous drive times obtained by repeating the drive and stop of the refrigerator 13b a plurality of times, and makes the drive reference time longer than the drive reference time. Set the judgment reference time. For example, the drive reference time may be an average value of a plurality of continuous drive times. As will be described later, the control unit 19 calculates an average value of the five continuous drive times (t1 to t5) and sets this average value as the drive reference time. Let the judgment reference time be tx drive reference time be ts.
tx = ts × α ... (1)
When, α may be larger than 1.0, for example, 1.2 ≦ α ≦ 2.0. Α described in the formula (1) corresponds to a multiplication factor of the determination reference time tx with respect to the drive reference time ts. By setting α to 1.2 or more, when cooling is performed at a cooling rate that can be regarded as within the normal range, the temperature can be cooled to the set lower limit temperature θb, further increasing the temperature inside the display chamber 2. Can be lowered. On the other hand, by setting α to 2.0 or less, it is possible to effectively prevent the continuous driving time of the refrigerator 13b from becoming long. Note that this α may be adjustable by the first adjusting means (not shown) of the refrigerated showcase 1. Further, the continuous drive time may be counted by using a timer (not shown) built in the control unit 19.

Then, the control unit 19 determines whether or not the temperature in the display chamber 2 is equal to or lower than the determination reference temperature when the determination reference time elapses without stopping after driving the refrigerator 13b. Control the refrigerator 13b. When the temperature in the display chamber 2 is equal to or lower than the determination reference temperature, the refrigerator 13b is stopped. The determination reference temperature is set to a temperature lower than the set upper limit temperature θa and higher than the set lower limit temperature θb. The determination reference temperature may be set as a low temperature equal to or less than an intermediate value between the set upper limit temperature θa and the set lower limit temperature θb. For example, let the judgment reference temperature be θx.
θx = θb + β ... (2)
Then, β described in the equation (2) is a numerical value larger than 0 (zero) and smaller than 1. For example, β may be 0.05 to 0.4. By setting β to 0.05 or more, it is possible to effectively prevent the continuous driving time of the refrigerator 13b from becoming long. On the other hand, by setting β to 0.4 or less, it is possible to prevent the determination reference temperature θx from moving away from the set lower limit temperature θb, and it is possible to prevent the temperature inside the display chamber 2 from rising. Note that this β (or θx) may be adjustable by a second adjusting means (not shown) of the refrigerated showcase 1.

Next, the operation of the present embodiment having such a configuration will be described. Here, the operation method of the refrigerated showcase 1 described above will be described. The operation method of the refrigerated showcase 1 is executed while the refrigerator 13b and the like are controlled by the control unit 19 described above.

First, as shown in FIG. 3, the refrigerator 13b of the refrigerated showcase 1 which has been stopped is started together with the fan 12. In this case, the operation is performed in the normal mode. Normally, since the temperature in the display chamber 2 measured by the temperature sensor 18 is higher than the set upper limit temperature θa, the refrigerator 13b is driven. At this stage, the operation in the intelligence mode described later is not performed. The fan 12 continues to be driven during the operation of the refrigerated showcase 1.

As shown in FIG. 3, when the refrigerator 13b is driven (ON), the temperature inside the display chamber 2 gradually decreases. Then, when the temperature in the display chamber 2 drops and reaches the set lower limit temperature θb, the refrigerator 13b is stopped.

When the refrigerator 13b is stopped (OFF), the temperature inside the display room 2 gradually rises due to the influence of the outside air temperature and the like. Then, when the temperature in the display chamber 2 rises and reaches the set upper limit temperature θa, the refrigerator 13b is driven again.

When the refrigerator 13b is driven again, the temperature in the display chamber 2 gradually decreases again. In this way, the refrigerator 13b is repeatedly driven and stopped during the operation in the normal mode. In the operation in the intelligence mode described later, basically, the driving and stopping of the refrigerator 13b are repeated in the same manner. Here, the period from when the refrigerator 13b is driven to when it is restarted after being stopped once is defined as one cycle. Normally, such a cycle is repeated during the operation of the refrigerated showcase 1.

The operation in the normal mode is performed until a predetermined initial time t0 elapses. The initial time t0 can be set arbitrarily. In FIG. 3, an example is shown in which the initial time t0 is set to a time such that the refrigerator 13b is driven and stopped once, but the refrigerator 13b is driven and stopped a plurality of times. It may be set at a time such that it takes place (ie, multiple cycles take place).

When the initial time t0 elapses after starting the refrigerator 13b, the operation is switched from the normal mode operation to the intelligence mode operation. In the operation in the intelligence mode, first, the determination reference time is set based on the continuous driving time of the refrigerator 13b. After that, the refrigerator 13b is controlled based on the determination reference time and the determination reference temperature. That is, in the operation in the intelligence mode, in addition to driving and stopping the refrigerator 13b in the normal mode described above, the determination reference time is set and the refrigerator 13b is controlled based on the determination reference time and the determination reference temperature. The operation in the intelligence mode will be described in more detail below.

First, the continuous drive time of the refrigerator 13b is sampled. That is, as shown in FIG. 3, after the initial time t0 has elapsed, the continuous drive time t1 in the first cycle C1 in which the refrigerator 13b is driven is sampled and continuously continues from the first cycle C1. The continuous drive time of the refrigerator 13b in each cycle is sampled. FIG. 3 shows an example in which the refrigerator 13b starts driving when the initial time t0 has elapsed. In this case, the cycle including the first drive of the refrigerator 13b may be the first cycle C1. On the other hand, if the refrigerator 13b is already driven or the refrigerator 13b is stopped when the initial time t0 elapses, the cycle in which the refrigerator 13b starts driving is the first cycle. Cycle C1 may be used.

Here, as an example, an example in which the continuous drive times t1 to t5 are sampled from the five cycles C1 to C5 and the determination reference time tx is calculated will be described.

In this case, first, the continuous drive times t1 to t5 of each cycle C1 to C5 are sampled. Subsequently, the average value of these continuous drive times t1 to t5 is calculated by the following equation (3), and this is used as the drive reference time ts.
ts = (t1 + t2 + t3 + t4 + t5) / 5 ... (3)

Subsequently, the determination reference time tx is set so as to be longer than the drive reference time ts calculated by the equation (3). For example, the determination reference time tx may be set by the above-mentioned equation (1).

Next, from the sixth cycle C6, the control of the refrigerator 13b based on the determination reference time tx and the determination reference temperature θx is started. That is, for the cycle C6 performed after the cycles C1 to C5 corresponding to the continuous drive times t1 to t5 for setting the determination reference time tx, the determination reference time has elapsed without stopping after driving the refrigerator 13b. In this case, it is determined whether or not the temperature in the display chamber 2 is equal to or lower than the determination reference temperature. In this case, the determination reference time tx is set based on the five continuous drive times t1 to t5 including the continuous drive time t5 in the cycle C5 immediately before the cycle C6 for determining whether or not the determination reference temperature is θx or less. Will be there. The case where the refrigerator 13b is not stopped and the case where the refrigerator 13b is stopped by the time when the determination reference time tx elapses after the refrigerating machine 13b is driven as the sixth cycle C6 will be described below.

If the refrigerator 13b is not stopped by the time when the judgment reference time tx elapses, whether or not the temperature in the display chamber 2 is equal to or less than the judgment reference temperature θx when the judgment reference time tx elapses. It is judged. When it is determined that the temperature in the display chamber 2 is equal to or less than the determination reference temperature θx, the refrigerator 13b is stopped.

FIG. 4 shows an example of temperature characteristics when the temperature in the display chamber 2 is higher than the set lower limit temperature θb but is equal to or lower than the judgment reference temperature θx when the determination reference time tx has elapsed. In this case, the refrigerator 13b is stopped when the determination reference time tx has elapsed. The continuous drive time t6a in the sixth cycle C6 is equal to the determination reference time tx. After the refrigerator 13b is stopped, the temperature in the display chamber 2 gradually rises without falling to the set lower limit temperature θb. Then, when the temperature in the display chamber 2 reaches the set upper limit temperature θa, the refrigerator 13b is driven again, and the cycle C7 shifts to the seventh cycle.

In FIG. 4, in the sixth cycle C6, the temperature characteristics when the refrigerator 13b is not controlled based on the determination reference time tx and the determination reference temperature θx are shown by broken lines. In this case, a lot of time is spent until the temperature in the display chamber 2 drops to the set lower limit value, and the continuous drive time t6a'of the refrigerator 13b becomes long. Therefore, it can be seen that by controlling the refrigerator 13b according to the present embodiment, the continuous driving time of the refrigerator 13b can be shortened by the time indicated by t6a'-t6a.

As another example of the temperature characteristics shown in FIG. 4, FIG. 5 shows a case where the temperature in the display chamber 2 is lower than the set upper limit temperature θa but exceeds the judgment reference temperature θx when the judgment reference time tx elapses. An example of the temperature characteristics of is shown. In this case, when the determination reference time tx elapses, the refrigerator 13b is not stopped, and the operation of the refrigerator 13b is continued thereafter. As a result, the temperature inside the display room 2 gradually decreases. After the determination reference time tx has elapsed, it is determined at an arbitrary time interval whether or not the temperature in the display chamber 2 is equal to or less than the determination reference temperature θx. By shortening this time interval, it becomes possible to continuously determine whether or not the determination reference temperature is θx or less.

When the temperature in the display chamber 2 reaches the determination reference temperature θx, the refrigerator 13b is stopped. In this case, the continuous drive time t6b in the sixth cycle C6 is longer than the determination reference time tx. After the refrigerator 13b is stopped, the temperature in the display chamber 2 gradually rises without falling to the set lower limit temperature θb. Then, when the temperature in the display chamber 2 reaches the set upper limit temperature θa, the refrigerator 13b is driven again, and the cycle C7 shifts to the seventh cycle.

In FIG. 5, in the sixth cycle C6, the temperature characteristics when the refrigerator 13b is not controlled based on the determination reference time tx and the determination reference temperature θx are shown by broken lines. In this case, a lot of time is spent until the temperature in the display chamber 2 drops to the set lower limit value, and the continuous drive time t6b'of the refrigerator 13b becomes long. Therefore, it can be seen that by controlling the refrigerator 13b according to the present embodiment, the continuous driving time of the refrigerator 13b can be shortened by the time indicated by t6b'-t6b.

The control of the refrigerator 13b based on the determination reference time tx and the determination reference temperature θx is continuously performed even after the seventh cycle C7. In both the example shown in FIG. 4 and the example shown in FIG. 5, the continuous drive times t6a and t6b in the sixth cycle C6 are equal to or longer than the determination reference time tx, and therefore the continuous drive times t6a and t6b. Is preferably not used in the calculation of the determination reference time tx. This is to prevent the determination reference time tx from becoming longer than necessary. In this case, the determination reference time tx in the seventh cycle C7 is the same as the determination reference time tx in the sixth cycle C6.

By the way, if the refrigerator 13b is stopped by the time the determination reference time tx elapses in the sixth cycle C6, the control of the refrigerator 13b based on the determination reference time tx and the determination reference temperature θx is performed for the cycle C6. Not done. For the seventh cycle C7, the determination reference time tx is reset using the continuous drive time of cycle C6. In this case, instead of the above equation (3), as shown in the following equation (4), the continuous drive time of the sixth cycle C6 is used instead of the continuous drive time t1 of the first cycle C1. The drive reference time ts is calculated. That is, the determination reference time tx is set based on the five continuous drive times including the continuous drive time in the cycle C6 immediately before the cycle C7 for determining whether or not the determination reference temperature is θx or less.
ts = (t2 + t3 + t4 + t5 + t6) / 5 ... (4)

Then, using the drive reference time ts calculated from the equation (4), the determination reference time tx is reset by the above equation (1). The reset criterion time tx is used for the operation of the intelligence mode of the seventh cycle C7.

In this way, in the operation in the intelligence mode, the setting of the determination reference time tx and the control of the refrigerator 13b based on the determination reference time tx and the determination reference temperature θx are repeatedly performed.

As described above, according to the present embodiment, when the determination reference time tx elapses without stopping after driving the refrigerator 13b, freezing is performed when the temperature in the display chamber 2 is equal to or less than the determination reference temperature θx. The machine 13b is stopped. This makes it possible to prevent the continuous driving time of the refrigerator 13b from becoming excessively long. Therefore, it is possible to suppress an increase in the power consumption of the refrigerator 13b. In addition, it is possible to suppress an increase in the amount of heat exhausted from the refrigerator 13b.

Further, according to the present embodiment, as described above, it is possible to prevent the continuous driving time of the refrigerator 13b from becoming excessively long. Therefore, it is possible to prevent the freshness of the products displayed in the display room 2 from being lowered.

That is, while the refrigerator 13b is being driven, the cold air (air) is cooled by the cooler 13a to which the refrigerant is supplied from the refrigerator 13b, and the cold air is dehumidified. This is because when the cooler 13a and the cold air exchange heat, the temperature of the refrigerant in the cooler 13a is low, so that the moisture in the cold air is deprived. The refrigerated showcase 1 according to the present embodiment is a face-to-face type, and the display room 2 is sealed with the sliding door 7 closed. Unwrapped foods (commodities) such as fresh cakes may be displayed in such a display room 2. When such foods are displayed, if dehumidified cold air is supplied into the display room 2, there is a problem that the displayed foods are dried and the freshness of the foods is lowered.

On the other hand, in the present embodiment, as described above, it is possible to prevent the continuous driving time of the refrigerator 13b from becoming excessively long. As a result, it is possible to prevent the food displayed in the display room 2 from drying out. Therefore, it is possible to suppress a decrease in the freshness of the food and improve the quality of the refrigerated showcase 1.

Further, according to the present embodiment, the drive reference time ts is calculated based on a plurality of continuous drive times, and the determination reference time tx is set so as to be longer than the drive reference time ts. As a result, the determination reference time tx can be set based on a plurality of continuous drive times, and the influence of the variation in the continuous drive time in each cycle of the determination reference time tx can be reduced. Therefore, the determination reference time tx can be set more appropriately. In particular, according to the present embodiment, the drive reference time ts is an average value of a plurality of continuous drive times. This makes it possible to easily and appropriately set the drive reference time ts.

Further, according to the present embodiment, the determination reference temperature θx is lower than the intermediate value between the set upper limit temperature θa and the set lower limit temperature θb. As a result, the determination reference temperature θx can be set to a temperature closer to the set lower limit temperature θb than the set upper limit temperature θa. Therefore, even when the temperature in the display chamber 2 is higher than the set lower limit temperature θb, the refrigerator 13b can be stopped in a state where the temperature is low to some extent, and the temperature in the display chamber 2 is kept low. be able to.

Further, according to the present embodiment, whether or not the temperature in the display chamber 2 is equal to or less than the determination reference temperature θx for the cycle performed after the cycle corresponding to the continuous drive time for setting the determination reference time tx. To judge. As a result, the continuous drive time for setting the determination reference time tx can be sampled from the cycle before the cycle for determining whether or not the determination reference temperature θx or less. Therefore, the determination reference time tx can be appropriately set by using the continuous driving time obtained from the refrigerated showcase 1 during operation. In particular, according to the present embodiment, the drive reference time ts can be calculated based on the continuous drive time in the cycle immediately before the cycle for determining whether or not the determination reference temperature is θx or less. As a result, the determination reference time tx can be set using the continuous drive time obtained under the same conditions as the ambient environment of the refrigerated showcase 1 at the time of determining whether or not the determination reference temperature is θx or less. Therefore, the change in the influence of the surrounding environment of the refrigerated showcase 1 can be effectively reduced, and the accuracy of determining whether or not the temperature is equal to or less than the determination reference temperature θx can be improved.

In the above-described embodiment, an example in which the drive reference time ts is calculated from the five continuous drive times t1 to t5 has been described. However, the present invention is not limited to this, and the sampling number (number of cycles) of the continuous drive time used for calculating the drive reference time ts may be more than 5, for example, the continuous drive time in each cycle. If there is little variation, it may be less than 5. The drive reference time ts may be calculated from one continuous drive time. When the number of samplings for the continuous driving time is reduced, the refrigerating machine 13b can be controlled based on the determination reference time tx and the determination reference temperature θx from an earlier cycle after the refrigerating showcase 1 is started. Even in this case, the determination reference time tx may be set to be longer than the drive reference time ts.

Further, in the above-described embodiment, an example in which the determination reference temperature θx is set by the above-mentioned equation (2) has been described. However, the determination reference temperature θx can be arbitrarily set as long as it is set to a temperature lower than the set upper limit temperature θa and higher than the set lower limit temperature θb.

Further, in the above-described embodiment, as the refrigerated showcase, the face-to-face refrigerated showcase 1 as shown in FIGS. 1 and 2 has been described as an example. However, the present invention is not limited to this, and the refrigerated showcase may be an open type refrigerated showcase 30 as shown in FIG. The refrigerated showcase 30 shown in FIG. 6 is not provided with the front surface 4 of the face-to-face refrigerated showcase 1 shown in FIGS. 1 and 2, and the display room 2 is opened forward. The sliding door 7 of the face-to-face refrigerated showcase 1 is not provided, and the display room 2 is covered with a rear wall 31 from the rear. The cold air cooled by the cooler 13a passes through a duct 32 provided behind the rear wall 31, and is displayed from the opening 33 provided in the rear wall 31 and the outlet 34 provided in the ceiling 5 to the display room 2. Supplied within. The products are displayed in the display room 2 and the products in the display room 2 are taken out from the front. Such an open type refrigerated showcase 30 has a temperature characteristic as shown in FIG. 3 because an air curtain, which is a flow of cold air, is formed in front of the display chamber 2. By operating in the intelligence mode described above, it is possible to suppress an increase in the power consumption of the refrigerator 13b even in the open type refrigerating showcase 30, and also to suppress an increase in the amount of heat exhausted from the refrigerator 13b. can do.

1 Refrigerator showcase 2 Display room 3 Base 4 Front part 5 Ceiling part 6 Side part 7 Sliding door 8 Display room bottom plate 9 Display shelf 10 Support 11 Lighting device 12 Fan 13 Cooling device 13a Cooler 13b Refrigerator 14 Suction port 15 Supply port 16 Cold air flow path 17 Drainage channel 18 Temperature sensor 19 Control unit 30 Refrigerator showcase 31 Rear wall 32 Duct 33 Opening 34 Blow-out part t1 to t5, t6a, t6b Continuous drive time ts Drive reference time tx Judgment reference time θa Set upper limit temperature θb Setting lower limit temperature θx Judgment reference temperature

Claims (8)

A refrigerated showcase that displays products while cooling them with cold air.
The display room where the products are displayed and
A circulation flow forming portion that circulates the cold air in the display chamber,
A cooler that cools the cold air with a refrigerant,
A refrigerant supply unit that supplies the refrigerant to the cooler,
A temperature measuring instrument that measures the temperature in the display room,
The refrigerant supply unit drives the refrigerant supply unit when the temperature in the display chamber is equal to or higher than the set upper limit temperature, and stops the refrigerant supply unit when the temperature in the display chamber is equal to or lower than the set lower limit temperature. With a control unit to control
The control unit sets a determination reference time based on the continuous drive time from driving the refrigerant supply unit to stopping the refrigerant supply unit.
When the determination reference time elapses without stopping after driving the refrigerant supply unit, the control unit has a temperature in the display chamber lower than the set upper limit temperature and higher than the set lower limit temperature. A refrigerating showcase that determines whether or not the temperature is below the determination reference temperature, and stops the refrigerant supply unit when the temperature in the display chamber is below the determination reference temperature. The refrigerated showcase according to claim 1, wherein the control unit calculates a drive reference time based on the plurality of continuous drive times, and sets the determination reference time to be longer than the drive reference time. The refrigerated showcase according to claim 2, wherein the drive reference time is an average value of a plurality of the continuous drive times. The refrigerated showcase according to claim 2 or 3, wherein when the determination reference time is tx, the drive reference time is ts, and tx = ts × α, α is 1.2 to 2.0. The refrigerated showcase according to any one of claims 1 to 4, wherein the determination reference temperature is lower than an intermediate value between the set upper limit temperature and the set lower limit temperature. The period from driving the refrigerant supply unit to being restarted after one stop is defined as one cycle.
When a plurality of the cycles are performed, the control unit determines that the temperature in the display chamber is the determination reference temperature for the cycle performed after the cycle corresponding to the continuous drive time for setting the determination reference time. The refrigerated showcase according to claim 1, which determines whether or not the following is true. The control unit calculates a drive reference time based on a plurality of continuous drive times including the continuous drive time in the cycle immediately before the cycle for determining whether or not the temperature is equal to or lower than the determination reference temperature, and the determination is made. The refrigerated showcase according to claim 6, wherein the reference time is set to be longer than the drive reference time. It is a method of operating a refrigerated showcase that displays products while cooling them with cold air.
A process of driving a refrigerant supply unit that supplies a refrigerant to a cooler that cools cold air when the temperature in the display room where the products are displayed rises to the set upper limit temperature.
A step of stopping the refrigerant supply unit when the temperature in the display chamber drops to the set lower limit temperature, and
A step of setting a determination reference time based on a continuous driving time from driving the refrigerant supply unit to stopping the refrigerant supply unit, and
When the determination reference time elapses without stopping after driving the refrigerant supply unit, the temperature in the display chamber is lower than the set upper limit temperature and higher than the set lower limit temperature below the determination reference temperature. A method of operating a refrigerated showcase, comprising a step of determining whether or not the refrigerant is present and stopping the refrigerant supply unit when the temperature in the display chamber is equal to or lower than the determination reference temperature.