JPS61191851A - Method of operating showcase - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method of operating a showcase for controlling the refrigeration device of a freezer or refrigerated showcase to maintain the temperature inside the refrigerator optimally and to save power. To properly manage the temperature of a showcase during non-business hours by smoothly changing the temperature when switching from the store business hours when the lights are turned on to the non-business hours when the lights are turned off.

The present invention will be explained in detail below with reference to the drawings.

Figure 1 (1) shows the opening (3) for storing and taking out products on the front.
A freezing or refrigerating showcase whose main body is composed of an insulating wall (2) formed with (
7), and an interior (11) equipped with a plurality of shelves (9) and a plurality of lights (10) such as fluorescent lights.
), and Suita and suction ports (12), (13), (14>(15)) of both the passages facing each other are formed at both upper and lower ends of the opening, and both the first and second passages (6) are formed. As shown by the arrows in (8), a two-layer air curtain (At) (A2) with different temperatures is formed in the opening (3) by the cold air flow and protective air flow circulated by the two wind losses (5) and (7), respectively. Inside the refrigerator (
11). Surrounded by a broken line (16
) is a refrigeration system, which includes a refrigerant compressor (17) and a condenser (18).
□ Liquid solenoid valve (19) □ Temperature expansion valve (20) □ Evaporator (
4) Compressors (17) are connected in a ring to form a known refrigeration cycle in which refrigerant is compressed, condensed, liquefied, decompressed, and evaporated.

(21) is a control device that controls the temperature inside the refrigerator (11);
A temperature sensor (22) that constantly detects the temperature of cold air in the showcase and a liquid electromagnetic valve (19) that controls the supply of liquid refrigerant to the evaporator (4) are connected to the device.

As shown in Figure 2, this device includes a power supply (23) and a processing section (24) that has built-in comparison and timer functions and compares each signal.
and a setting section (25) that stores each temperature setting value to be controlled and outputs a signal with a time width corresponding to the temperature inside the warehouse (11), and a setting section (25) that stores the temperature setting values to be controlled and outputs a signal with a time width corresponding to the temperature inside the warehouse (11), and a setting section (25) that outputs a signal with a time width corresponding to the temperature inside the warehouse (11). A day/night switching unit (26) that outputs a signal during non-business hours, the temperature sensor (22), and an output unit (2) that controls the opening/closing operation of the liquid electromagnetic valve (19) by turning on and off according to the signal from the processing unit.
7).

Next, the showcase (1) by the shaking control device (21)
Each temperature control will be explained with reference to FIGS. 3 to 5. In each figure, (L,) is the temperature curve of the circulating cold air detected by the temperature sensor (22), (L is the signal waveform of the output part (27) that controls the opening and closing of the liquid solenoid valve (19), and (L) is the temperature curve of the circulating cold air detected by the temperature sensor (22). , ) is the signal waveform of the day/night switching unit (26), (TS') is the lower limit setting value during business hours, (TD) is the upper limit setting value in the special sales number, (TN) is the lower limit setting value during non-business hours, ( TD'
) is the upper limit setting value during non-business hours, (6 lights) is the lighting (1 light)
0) shows the temperature range of automatic setting change at night when the lights are turned off.

Figure 3 shows the characteristics of both on/off and night setback control, and when the day/night switching signal (L,) is OFF, that is, during store business hours when the light (10) is on, the lower limit setting value ( 'I'S) turns the output signal (L, ) OFF, and the upper limit setting value turns the output signal (L, ) of the output section (27) OFF.
N and repeats on/off control, and when the day/night switching signal (Ll) turns on, the output signal (L,) is turned off to forcibly close the liquid solenoid valve (19), which is called automatic night setting change. Moving on to the night setback, lighting (10)
The lower limit setting value (IN
”) to turn off the output signal (L, ) and set the upper limit value (TD').
), the output signal (L, ) is turned on to perform on-off control.

Figure 4 shows the characteristics of on/off, night setback, and duty cycle control. During business hours, the timer of the processing unit (24) outputs the output signal (Lm ) during on/off control, forcibly closes the liquid solenoid valve (19) and performs daytime duty cycle control in which the supply of liquid refrigerant to the evaporator (4) is intermittently stopped; During non-business hours, the period (τ) is (τha((τ
s)> (τ3)), the output signal (L,) is set to 0FF1.
, on/off, night setback, and nighttime duty cycle control in which the liquid solenoid valve (19) is closed and the liquid refrigerant to the evaporator' (4) is intermittently stopped. Also in this control, when changing from business hours to non-business hours, the liquid solenoid valve (19) is closed, resulting in automatic setting change at night.

FIG. 5 shows the override characteristics in duty cycle control, where (I'R) shows the temperature width of the duty cycle, and (L4) shows the override signal waveform. During the cooling operation stop due to the duty cycle, the noodle skins in the showcase (1) rise as shown in the chain line, which has a negative impact on the product load. In this case, the temperature ((T
S) + (TR) or (TN) + (TR)), the output signal (L) is immediately turned ON and an override is performed to forcefully return to cooling operation. Operation stops due to temperature (TS)
or down to (TN) ((τ)-(τ,) or (at)-
It is carried out after (τui).

Therefore, according to the operating method of the showcase (1),
When the store is not open, when the light (10) is turned off and the heat generated by this light does not become a refrigeration load, the heat generated by the light (10) is lower than when the store is open. Since the refrigerator can be made lighter, the temperature inside the refrigerator during non-business hours can be set higher than the temperature inside the refrigerator during business hours, allowing for light-load operation of the refrigeration equipment (items). When transferring items during business hours, the evaporator (
4) By forcibly stopping the supply of liquid refrigerant to the refrigerator, the temperature inside the refrigerator will automatically rise and reach the set value for non-business hours, so switching from business to non-business hours will be possible. can be carried out smoothly, and the temperature of the showcase (1) can be easily controlled.゛According to the present invention described above, the temperature of the showcase can be controlled depending on whether the lights inside the warehouse are on during business hours or off when the lights are off, and it is possible to smoothly switch from business hours to non-business hours or vice versa. can be done.

[Brief explanation of drawings]

The drawings show an embodiment of the method of operating the showcase of the present invention,
FIG. 1 is a longitudinal sectional view of the showcase, FIG. 2 is a block diagram of the control device, and FIGS. 3 to 5 are characteristic diagrams showing the operation of the control device. (4)...Evaporator, (5)...Blower, (10
)...Lighting, (11)...Interior, (21)...
Control device, (22)...Temperature sensor, (24)
...Processing section, (25)...Setting section, (26)...
- Day/night switching section, (27)...output section. Applicant Sanyo Electric Co., Ltd. and 1 other representative Patent attorney Shizuka Sano Visit 1v! i Figure 2 Figure 3

Claims (1)

[Claims] 1. In a showcase where the cold air that has been heat exchanged with an evaporator is forcedly circulated by a blower to cool the inside of the store to a predetermined temperature, the temperature inside the store is set at a temperature higher than this set value during store business hours. A method of operating a showcase comprising forcibly stopping supply of liquid refrigerant to the evaporator when switching to a set value of the temperature inside the refrigerator.