KR970005543B1 - Showcase control device - Google Patents

Abstract

None.

Description

Low Temperature Showcase Control

1 is a convex view of a control device of a low temperature showcase of the present invention.

2 is a schematic longitudinal section of a low temperature showcase.

3 is a functional block diagram of a microcomputer.

4 is a functional block diagram of a control apparatus of a conventional low temperature showcase.

* Explanation of symbols for main parts of the drawings

1: insulation wall 2: cooler

3: inlet port 4: discharge port

5: cold air passage 6: blower

7: shelf height 8: shelf

9: wire rack 10: high internal lighting

11: microcomputer (control means) 12: illuminance setting switch

13: Reflector 14: High Light Switch

15: discharge cooler temperature setter (discharge cooler temperature setting means)

16: discharge cool air temperature sensor (discharge cool air temperature detection means)

18: Compressor 19: Electronic ballast (light intensity change means)

20: low temperature showcase 21: setting unit

22 measuring unit 23 comparing unit

24: output unit 26: the first decision

27: 2nd judgment board 28: setting temperature changing part (setting temperature changing means)

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a control apparatus for a low temperature show case for displaying and preserving food while cooling food.

Conventionally, this kind of low-temperature showcase is installed in a store such as a supermarket market, and displays goods while cooling the inside of the high-temperature structure constituted by a heat insulating wall to a low temperature by a cooling device.

In addition, such a showcase has a large invasion of heat load from the front opening, and it is extremely unstable to directly detect the internal temperature and perform temperature control, for example, in Japanese Patent Application Laid-Open No. 54-99256 (F 25 D 11). / 00) inserts a temperature sensor cylinder into the cold air passage, which is far from the inside where the goods are actually stored, and has a low temperature influence from the outside, detects the temperature of the discharged cold air discharged in the air, and compares the discharged cold with the set temperature. A configuration for controlling is proposed.

In such a low temperature showcase, the lights in the store are turned off at the same time as the lights in the store are turned off at the time of closing, such as at night, which is a non-business hours.

Therefore, after closing, the temperature rise due to the heat generation of the high-intensity light that becomes the load is eliminated, but the temperature of the discharged cold air detected by the temperature sensor box is the same as the opening time during the opening hours, etc. By the temperature rise by, the internal temperature of the refrigerator is lowered at the time of closing, the product is excessively cooled and the operation rate of the cooling device becomes higher than necessary, resulting in waste of power.

In particular, in recent years, food is preserved in a temperature zone where food is not frozen at 0 ° C or below, that is, in an ice temperature zone (about 0 ° C to -3 ° C), thereby preventing long-term preservation while preventing quality degradation caused by cell membrane destruction caused by freezing and thawing. The low temperature showcase is increasing, and in such a low temperature showcase, there is a problem in that food is easily frozen when supercooling occurs at the time of closing.

In the above publication, when the high-temperature lighting is turned off at the closing of the night or the like, the high-temperature temperature is controlled at the same temperature as the high-temperature lighting is turned on by changing the set temperature to a predetermined rise.

That is, the temperature control of such a conventional low temperature showcase will be described based on FIG.

4 shows a functional block of the control apparatus of the conventional low temperature showcase proposed in the above publication, wherein the set temperature TDS of the discharge cold air is input to the setting unit 100 and the discharge cold temperature TD described above. ) Is input to the measuring unit 101.

The comparing unit 102 sets the upper limit temperature and the lower limit temperature at a predetermined difference width above and below the setting temperature TDS based on the setting temperature TDS from the setting unit 100, and then measures the upper limit temperature and the lower limit temperature from the measuring unit 101. When the discharge cold air temperature TD reaches the above upper limit temperature, an output is generated at the output unit 103 to operate a compressor of a cooling device (not shown), or the electric valve for refrigerant flow control is opened, and the discharge cold air temperature TD is generated. Reaches the lower limit temperature, generates an output to the output unit 103 to stop the compressor or closes the electric valve for refrigerant flow control.

As a result, the discharge cooling air temperature TD is controlled to the set temperature TDS.

On the other hand, the on / off state of the high internal light on the basis of the switching operation of the high internal light switch (not shown) is input to the judging unit 104, where it is determined whether the high internal light is on or off and the set temperature (TDS) is turned on. ) Does not need to be changed, so it does not act on the lower setting unit 100.

Here, when the high internal lighting is turned off by the closing, a signal is transmitted from the determination unit 104 to the set temperature changing unit 105 (indicated by a dotted line in the drawing), and the set temperature changing unit 105 uses this signal to set the setting unit ( Command 100) to change the set temperature (TDS) to 3 to 6 ° C.

The setting unit 100 raises the setting temperature by such a command, for example, the above-described TDS + 3 ° C, whereby the comparison unit 102 moves above and below the elevated set temperature TDS + 3 ° C. Similarly, when the discharge cold air temperature TD from the measuring unit 101 reaches its upper limit temperature by newly setting the upper limit temperature and the lower limit temperature with a predetermined difference width, an output unit 103 generates an output to the cooling unit (not shown). Of the compressor or by opening the electric valve to reach the lower limit temperature of the discharged cold air temperature (TD), generating an output to the output unit 103 to stop the compressor or to close the electric valve.

As a result, the discharge cooling air temperature TD is raised by the decrease of the heat load in the furnace accompanied by the high internal light extinction, thereby preventing the occurrence of supercooling at the extinction.

By the way, in recent years, the illuminance of high-intensity illumination (fluorescent lamp) is changed by the electronic ballast comprised by the inverter which can change the power frequency applied to fluorescent lamp.

For example, when the daytime is clear, the interior lighting is made bright according to the brightness, and when it is cloudy, the interior lighting is darkened in accordance with the darkness of the outdoors, and the difference between the brightness of the outdoors is reduced and the products in the interior are more natural. It is intended to be visible to the customer in brightness.

However, since the amount of heat generated in the interior from the interior lighting is also changed by such a change in the illumination, when the interior lighting is reduced, there is a problem in that the interior temperature is unnecessarily lowered by the amount of the heat loss as in the case of the light-off described above. .

The present invention has been made to solve such a technical problem, and an object of the present invention is to provide a low temperature showcase control device capable of accurately controlling a high internal temperature even when a high internal light intensity is changed.

The control device of the low temperature showcase of the present invention is applied to a low temperature showcase for cooling by discharging cold air heat-exchanged with a cooler included in a cooling device in a room, and illuminating the inside of the high lighting and changing the illuminance of the high lighting. Change means, discharge cold air temperature detection means for detecting the temperature of the discharge cold air discharged into the chamber, control means for controlling the cooling apparatus based on the temperature detected by the discharge cold air temperature detection means and the set temperature of the discharge cold air; And setting temperature changing means for changing the set temperature of the discharge cold air, and the setting temperature changing means has a predetermined rise in the predetermined temperature range when the illuminance changing means is reduced by the illuminance changing means when the lighting is turned on. It characterized in that to change.

The control means controls the cooling apparatus based on the temperature of the discharge cold air detected by the discharge cold air temperature detecting means and the set temperature of the discharge cold air.

When the illuminance change means reduces the illuminance of the high illuminance at the time of illuminating the high illuminance light, the set temperature change means changes the set temperature of the discharged cold air to a predetermined rising width.

Thereby, the control means controls the cooling apparatus based on the elevated set temperature and the temperature of the discharged cold air, and the temperature of the discharged cold air is increased by the decrease of the amount of heat from the high internal lighting, and the high internal temperature is controlled as before the illuminance change. .

(Example)

Next, embodiments of the present invention will be described in detail with reference to the drawings.

FIG. 1 shows a block diagram of the control device C of the low temperature showcase 20, and FIG. 2 shows a schematic longitudinal sectional view of the low temperature showcase 20. As shown in FIG.

In FIG. 2, the low temperature showcase 20 is a so-called open showcase installed at a convenience store or a supermarket market, and a cooler 2 constituting a cooling device is provided at a lower portion of the heat insulation wall 1 having an open front surface. The cold air passage 5 is formed from the inlet port 3 installed at the lower part of the heat insulating wall 1 to the cooler 2 and the discharge port 4 provided at the upper side of the heat insulating wall 1 of the heat insulating wall 1. By circulating the cool air cooled by heat exchanger with the cooler 2 by the blower 6 as indicated by the arrows, the cool air is supplied to the interior 7 and the heat insulating wall from the discharge port 4 to the suction port 3 ( The air curtain is formed in the opening of 1), the goods displayed on the shelf 8 and the wire rack 9 for goods display in the inside of 7 are cooled, and the goods are kept at low temperature.

Moreover, in the interior 7, in order to increase a display effect, the interior lighting 10 which consists of fluorescent lamps is provided in the vicinity of each shelf 8 and the discharge port 4, respectively.

In the control apparatus C of FIG. 1, reference numeral 11 denotes a general-purpose microcomputer as the control means, and the microcomputer 11 has an illuminance not shown in FIG. 2 for setting and turning the illuminance of the interior lighting 10 into light / dark. Temperature of the high temperature light switch 14 and the inside of the refrigerator 7 installed on the lower surface of the reflector 13 of the low temperature showcase 20 to switch the setting switch 12 and the lighting / lighting off of the above-mentioned high lighting 10. In order to set the temperature, the temperature of the discharge cold air temperature setter 15 and the discharge cold air flowing in the cold air passage 5 are actually detected as the discharge cold air temperature setting means for setting the temperature of the discharge cold air flowing in the cold air passage 5. Each output of the discharge cool air temperature sensor 16 as the discharge cool air temperature detection means is input.

The discharge cold air temperature setter 15 is provided in the reflector 13, and the handle thereof faces the lower surface of the reflector 13. As shown in FIG.

On the other hand, the compressor 18 and the blower 6 constituting the cooling device are connected to the output of the microcomputer 11, and an electronic ballast 19 as an illuminance changing means made of an inverter is connected. The internal lighting 10 mentioned above is connected to 19.

The microcomputer 11 controls to turn on or turn off the high internal light 10 based on the operation of the high internal light switch 14 described above by the user.

In addition, the microcomputer 11 changes the power supply frequency of the high internal lighting 10 generated by the electronic ballast 19 based on the operation of the illuminance setting switch 12 by the user, so that the high internal lighting 10 has a high frequency. That is, it controls the switching to the bright state and the low frequency, ie the dark state.

Next, the temperature control operation of the low temperature showcase 20 by the microcomputer 11 will be described using the functional block diagram of FIG.

FIG. 3 shows a functional block for temperature control of the microcomputer 11, wherein the set temperature TDS of the discharge cooler set as the discharge cooler temperature setter 15 is a setting unit as a function of the microcomputer 11; The discharge cool air temperature TD inputted at 21 and detected by the discharge cool air temperature sensor 16 is input to the measuring unit 22.

The comparison unit 23 as a function of the microcomputer 11 sets the upper limit temperature and the lower limit temperature at a predetermined difference width above and below the setting temperature TDS based on the setting temperature TDS from the setting unit 21. When the discharge cold air temperature TD from the measuring unit 22 reaches the above upper limit temperature, the output unit 24 generates an output to operate the compressor 18 (the blower 6 is operated continuously), and the discharge cold air is discharged. When the temperature TD reaches the lower limit temperature described above, the output unit 24 generates an output to stop the compressor 18.

As a result, the discharge cooling air temperature TD is controlled to the set temperature TDS.

In addition, when a plurality of low temperature showcases 20 are installed, and a condenser including the compressor 18 is separately installed and the refrigerant flow is controlled by the cooler 2 of each low temperature showcase 20 by an electric valve. The microcomputer 11 compares the above-mentioned temperature TD of the discharged cold air with the set temperature TDS, and performs opening / closing control of this electric valve.

On the other hand, the light / dark setting of the high interior lighting 10 based on the switching operation of the illuminance setting switch 12 is input to the first determination unit 26 as a function of the microcomputer 11, where the high interior lighting 11 is It is determined whether it is set to the bright state or the dark state.

In addition, the on / off state of the high internal light 10 based on the operation of the high internal light switch 14 is input to the second judging unit 27, where it is determined whether the high internal light 10 is turned on or off.

When the high internal lighting 10 is turned on and the illuminance is set to a bright state, it is not necessary to change the set temperature TDS. Therefore, it does not act on the lower setting unit 21 (in the middle of the third line). Indicates).

Here, when the internal lighting 10 is turned off by the closing, a signal is transmitted from the second judging unit 27 to the setting temperature changing unit 28 as the setting temperature changing unit (indicated by a dotted line in FIG. 3). 28) instructs the setting unit 21 to change the set temperature TDS to a rise of 3 to 6 ° C by this signal.

The setting section 21 raises the set temperature by, for example, TDS + 3 ° C as described above, whereby the comparison section 23 above and below the elevated set temperature TDS + 3 ° C. The upper limit temperature and the lower limit temperature are newly set to a predetermined difference width as described above, and when the discharge cold air temperature TD from the measuring unit 22 reaches the upper limit temperature, an output is generated at the output unit 24 so that the compressor ( 18), when the discharge cold air temperature TD reaches its lower limit temperature, the output unit 2 generates an output to stop the compressor 18.

As a result, the discharge cooling air temperature TD is increased by the decrease of the heat load of the interior 7 accompanied by the extinguishing of the interior lighting 10, thereby preventing the occurrence of supercooling at the time of extinguishing.

Next, when the interior lighting 10 is turned on, for example, because the outdoor is dark, when the user sets the interior lighting 10 to a dark state by the illuminance setting switch 12, the first judgment unit 26 Signal is transmitted to the set temperature changing section 28 (indicated by a dashed line in FIG. 3), and the set temperature changing section 28 sets the set temperature TDS to the set section 21 by 0.5 DEG C. Command to change to rising range of.

The setting section 21 raises the set temperature by the command as the above-mentioned TDS + 0.5 deg. C, whereby the comparison unit 23 then sets the predetermined temperature as above and below the elevated set temperature TDS +0.5 deg. When the discharge cold air temperature TD from the measuring unit 22 reaches the upper limit temperature by newly setting the upper limit temperature and the lower limit temperature as the difference width, the compressor 18 is operated by generating an output to the output unit 24, When the discharge cold air temperature TD reaches its lower limit temperature, the output unit 24 generates an output to stop the compressor 18.

This raises the discharge cooling air temperature TD by the decrease (less than at the time of turning off) the heat load of the interior 7 accompanying the fall of the roughness of the interior lighting 10, and thereby prevents the occurrence of supercooling at the time of the roughness reduction. At the same time, the operation rate of the compressor 18 is lowered to reduce the power consumption.

In addition, in the above-described embodiment, the set temperature is changed in both the time of turning off the high illumination 10 and reducing the illuminance, but it is effective to carry out only when the high illumination 10 is reduced.

In addition, the value of each temperature shown in the Example is not limited to that, It cannot be overemphasized that it can change suitably based on the capability and the capacity | capacitance of the low temperature showcase 20. As shown in FIG.

According to the present invention as described above, when the illuminance of the low temperature showcase is turned on, when the illuminance is reduced, the set temperature of the discharge cold air is changed to a predetermined rising width, and thus the inner quantity due to the decrease in Young's quantity accompanying the illuminance decreases. By eliminating the supercooling of the temperature, it is possible to appropriately manage the low temperature showcase and at the same time reduce the power consumption.

Claims (1)

In the low temperature showcase 20 which cools by discharging the cold air heat-exchanged with the cooler 2 contained in a cooling apparatus to the inside of the inside of the inside of the inside of a refrigerator 7, The inside lighting 10 which illuminates the inside of the inside of the inside of the refrigerator 7, and its inside Illuminance changing means 19 for changing illuminance of the illumination 10, discharge cold air temperature detecting means 16 for detecting the temperature of the discharge cold air discharged into the inside of the refrigerator 7, and the discharge cold air temperature detecting means. Control means (11) for controlling the cooling device based on the temperature detected by (16) and the set temperature of the discharge cool air, and set temperature change means (28) for changing the set temperature of the discharge cool air; And the set temperature changing means 28 has a predetermined value when the illuminance of the above-mentioned high-temperature light 10 is reduced by the above-mentioned illuminance-changing means 19 at the time of lighting of the above-mentioned high-temperature light 10. Low temperature shokei, characterized in that for changing the set temperature in the rising range of Control device.