JPH0765220A - Power saving device for vending machines - Google Patents

Abstract

(57) [Summary] [Purpose] Instead of simply setting the time with a timer, save electricity appropriately according to the actual sales situation. [Composition] A compressor (5), a valve (6) for guiding a refrigerant to an evaporator in a refrigerator, a heater (2), an inside temperature sensor (3), and an inside temperature are set to a preset ON temperature and OFF temperature. A power saving device for a vending machine comprising a drive control circuit (12) for controlling on / off of a compressor (5) or a heater (2) by comparison, which is a timepiece (8), the inside temperature sensor (3) and From the temperature and time in the refrigerator obtained from the clock (8), the temperature gradient detector (9) that detects the gradient of the temperature change in the refrigerator and the detected temperature gradient are compared with the value of the reference temperature gradient to determine the sales frequency. A sales frequency determination means (10) for determining whether the sales amount is small and an on / off temperature shift unit (11) for shifting the on temperature and the off temperature for power saving operation when it is determined that the sales frequency is low.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a device for saving power in a vending machine that heats and cools products with a heater or a compressor.

[0002]

2. Description of the Related Art As a conventional power saving device, the operation of a heater or a compressor is stopped at a preset time (for example, a midnight when there are few sales opportunities), or the ON temperature and In the compressor, the off temperature is shifted upward (downward for the heater) to shorten the operating time of the equipment and save electricity.

[0003]

However, in such a power saving method, even if there are frequent sales at night, the product is not in an appropriate temperature because of the power saving operation.
Even though there was no sales during the day, the products were heated and cooled more than necessary, so it was not possible to save electricity in line with the sales situation.

The present invention has been made to solve the above problems, and an object of the present invention is to provide a device capable of saving power suitable for an actual sales situation.

[0005]

According to the present invention, a compressor (5) for condensing a refrigerant, a valve (6) for guiding the condensed refrigerant to an evaporator in the refrigerator, a heater (2) for heating the inside of the refrigerator, Internal temperature sensor (3) for detecting internal temperature, drive for controlling on / off of compressor (5) or heater (2) by comparing internal temperature with preset on temperature Ton and off temperature Toff A power saving device for a vending machine comprising a control circuit (12), which comprises a timepiece (8) for measuring time, an in-compartment temperature and time obtained from the in-compartment temperature sensor (3) and the timepiece (8), Temperature gradient detection unit that detects the gradient of the temperature change in the refrigerator
(9), a sales frequency determination means (10) for determining whether the sales frequency is high or low by comparing the detected temperature gradient with the value of the reference temperature gradient, and when it is determined that the sales frequency is low,
An on-off temperature shift unit (11) for shifting the on-temperature Ton and the off-temperature Toff for power saving operation,
It is characterized by having.

[0006]

FIG. 1 is a diagram showing a temperature change in the refrigerator. The compressor (5) is operated until the inside temperature of the refrigerator initially at room temperature drops to the off temperature, and the compressor (5) is stopped. After that, the internal temperature gradually rises, and when the internal temperature rises, the compressor (5) is operated again. Where Δ
Kd / ΔTd is the falling temperature gradient ad during compressor operation.
And ΔKu / ΔTu is the rising temperature gradient au when the compressor is stopped.

FIG. 2 shows a temperature change when the sales frequency is relatively high, and FIG. 3 shows a case where the sales frequency is relatively low. It can be seen that during cooling, the cooling time t ′ ₁ from the ON temperature to the OFF temperature when the sales frequency is low is shorter than the time t ₁ when the sales frequency is high, and the descending temperature gradient ad is large.

On the other hand, at rest of the compressor (5), the time t _'2 from off temperature when less sales frequently up to on temperature is longer than the time t ₂ when a lot of sales frequency,
Therefore, it can be seen that the rising temperature gradient au is small.

Therefore, when the falling temperature gradient ad detected by the temperature gradient detecting section (8) is larger than the reference temperature gradient Xd, and when the rising temperature gradient au is smaller than the reference temperature gradient Xu. It can be judged that the sales frequency is low,
In that case, the ON temperature and the OFF temperature of the compressor (5) are shifted upward in order to save power.

FIGS. 4 and 5 show temperature changes during heating by the heater (2) when the sales frequency is high and when the sales frequency is low. The heating time t ′ ₁ from the ON temperature to the OFF temperature when the sales frequency is low is shorter than the time t ₁ when the sales frequency is high, and the rising temperature gradient au is large. When the heater (2) is at rest, the time t ′ ₂ from the off temperature to the on temperature when the sales frequency is low is longer than the time t ₂ when the sales frequency is high, and the falling temperature gradient ad is small.

Therefore, when the rising temperature gradient au is larger than the reference temperature gradient Xu, and the falling temperature gradient ad is
When the temperature gradient is smaller than the reference temperature gradient Xd, it can be determined that the sales frequency is low, whereby the ON temperature and the OFF temperature of the heater (2) can be shifted downward to save power.

Incidentally, in detecting the rising temperature gradient au and the falling temperature gradient ad, it is preferable to take an average value over a plurality of past times.

FIG. 6 and FIG. 7 show the temperature changes in the cooling box when the sales frequency is constant but the temperature difference between the inside temperature and the outside temperature is large and small. Also in this case, the same tendency as in FIGS. 2 and 3 appeared. That is,
When the temperature difference is small (FIG. 7), the falling temperature gradient ad is large and the rising temperature gradient au is small as compared with the case where the temperature difference is large (FIG. 6). Therefore, the temperature change depending on the sales frequency shown in FIGS. 2 and 3 is more remarkable when the temperature difference is large, and the descending temperature gradient ad is further large.
The rising temperature gradient au becomes smaller.

By the way, the temperature gradient detected by the temperature gradient detecting section (9) includes the influence of the temperature difference, and in order to know the accurate sales frequency, the influence of the temperature difference must be eliminated. I won't. Therefore, in the second invention, the reference temperature gradients Xd and Xu are changed to appropriate values based on the detected temperature difference, thereby further improving the power saving accuracy. Similar measures can be taken for the heating cabinet.

FIG. 8 and FIG. 9 show the temperature changes when the number of products remaining in the storage is large and when the number of products remaining is small. When both the gradient and the rising temperature gradient are small and the number of remaining products is small, the gradient becomes large on the contrary. Therefore, also in this case, in order to eliminate the influence of the number of remaining products, the second invention also changes the reference temperature gradients Xd and Xu to appropriate values according to the number of remaining products, thereby further improving the power saving accuracy. Is improving.

[0016]

FIG. 10 is a control block diagram of an automatic vending machine to which the control device of the first invention is applied. There are three product storages (1a, 1b, 1c), each of which has a heater 2a, 2b, 2c for heating, a storage temperature sensor 3a, 3b, and
3c, the evaporator 4a, 4b, 4c which is an evaporator is provided. 5 is a compressor for condensing the refrigerant, 6a,
Reference numerals 6b and 6c are valves that guide the refrigerant condensed in the compressor 5 to the evaporators 4a, 4b and 4c.

Reference numeral 7 is a temperature Ton for turning on the heater 2 and a temperature Toff for turning off the compressor 5 (Ton (H), Toff (H) for the heater, and Ton (for the compressor 5 C) and Toff (C)) is an on / off temperature setting unit for externally setting. Reference numeral 8 is a clock for measuring the time. 9 is a temperature gradient calculation unit,
On / off temperatures Ton, Tof from the on / off temperature setting unit 7
Based on f, the time from the clock 8, and the internal temperature from the internal temperature sensor 4, the average falling temperature of the internal temperature during the past n cycles (one operation cycle of the heater 2 and the compressor 5 is called one cycle) ad and average temperature rise au
Is calculated for each heating chamber and cooling chamber (
(H), au (H), and in a cooler are referred to as ad (C) and au (C)).

Numeral 10 is an on / off temperature shift section, and in the refrigerator, the falling temperature gradient ad (C) exceeds the reference falling temperature gradient Xd, and the rising temperature gradient au (C) is the reference rising temperature. Only when the gradient falls below the gradient Xu, the ON temperature Ton and the OFF temperature Toff supplied from the ON / OFF temperature setting unit 7 are shifted upward for power saving operation, and the ON temperature T'on and the OFF temperature T'off are output. In the heating chamber, the falling temperature gradient ad (H) is below the reference falling temperature gradient Xd, and the rising temperature gradient au (H) is the reference rising temperature gradient Xu.
The above-mentioned on temperature Ton and off temperature Toff
For the power saving operation, the ON temperature T'on and the OFF temperature T'off shifted downward are output. 12 is an on / off temperature To supplied from the on / off temperature shift unit 10.
n, Toff or shifted on / off temperature T'on, T'off
Is a drive control circuit that drives the heater 2, the compressor 5, and the valve 6 by comparing the temperature T in the inside temperature T from the inside temperature sensor 4.

The control operation in the refrigerator in the control device having the above-mentioned configuration will be described with reference to the flowchart of FIG. In step S1, the temperature change in the cold storage during the past n cycles of operation is detected, and in step S2, the n falling temperature gradients ad 'and the rising temperature gradient au' are calculated, and their respective averages are calculated. The average falling temperature gradient ad as a value
(C) and average rising temperature gradient au (C) are calculated. In step S13, it is determined whether or not the average falling temperature gradient ad (C) exceeds the reference falling temperature gradient Xd (C), and if it exceeds, the average rising temperature gradient au (C) is set as the reference in step S14. It is determined whether or not the temperature rise is lower than the rising temperature gradient Xu (C).
At, the on temperature Ton and the off temperature Toff are respectively shifted upward by, for example, 3 ° C. to perform the power saving operation.

On the other hand, steps S13 and S1
If even one of the judgment expressions in 4 does not hold, it is judged that the sales frequency is high, and in step S16, if the power saving operation is currently being performed, the shift of the on temperature Ton and the off temperature Toff is cleared to save the power. Stop driving.

FIG. 12 shows the operation in the case of a refrigerator, in which the average falling temperature gradient ad (H) is below the reference falling temperature gradient Xd (H) (step S13 '), and the average When the rising temperature gradient au (H) exceeds the reference rising temperature gradient Xd (H) (step S14 '), the on / off temperature is shifted downward for power saving operation (step S15').

FIG. 13 is a control block diagram of the device of the second aspect of the present invention, and is different from FIG. 10 in that an outside air temperature sensor 13 for detecting the outside air temperature is provided. The control operation will be described with reference to the flowchart of FIG.

In step S21, the temperature change in the cold storage and the outside air temperature during the past n cycles of operation are detected.
At 22, an average value T of the temperature difference between the outside temperature and the inside temperature is calculated. Then, in step S23, the average falling temperature gradient a
Calculate d (C) and average rising temperature gradient au (C).

In the next step S24, the sales frequency determination unit 10 'determines whether the average falling temperature gradient ad (C)> αT · Xd (C). α is a temperature coefficient, and αT · Xd (C) on the right side of this determination formula is the corrected reference falling temperature gradient.

When the above judgment formula is satisfied, further, in step S25, the average temperature rise gradient au (C) <αT · Xu (C).
If it is satisfied, it is determined that the sales frequency is low, and in step S26, each on / off temperature is shifted upward to perform the power saving operation. On the other hand, if even one of the upper and lower determination expressions is not satisfied, the process proceeds to step S27, and if the power saving operation is currently being performed, the power saving operation is ended. In the case of the heating chamber, the power saving operation can be performed in the same manner.

FIG. 15 is a control block diagram of the device according to the third aspect of the present invention, and is different from FIG. 10 in that a remaining product number detection unit 14 for detecting the number of stored products is provided, which is used in a refrigerator. The control operation will be described with reference to the flowchart of FIG. In this case, in step S31, the internal temperature change during the past n cycles of operation and the current number of remaining products are detected, and the average Z of the number of remaining products is calculated in step S32. Then, in step S33, the average falling temperature gradient ad (C) and the average rising temperature gradient au (C) are calculated.

In the next step S34, the sales frequency determination unit 10 "determines whether or not the average falling temperature gradient ad (C)> βZ · Xd (C). Β is a product inventory quantity coefficient. The right side of the judgment formula, βZ · Xd (C), becomes the corrected reference falling temperature gradient.

If the above judgment formula is satisfied, then in step S35, the average temperature rise gradient au (C) <βZ · Xu (C).
If it is satisfied, it is determined that the sales frequency is low, and in step S36, the respective on / off temperatures are shifted upward to perform the power saving operation. On the other hand, if at least one of the upper and lower determination expressions is not satisfied, the process proceeds to step S37, and if the power saving operation is currently being performed, the power saving operation is ended.

[0029]

As described above, according to the present invention, it is determined that the sales frequency is high or low based on the detected temperature change in the refrigerator, and the power saving operation is performed when the sales frequency is low. It is possible to perform power saving operation according to the sales situation of. Further, the accuracy of the power saving operation can be further improved by appropriately correcting the inside temperature affected by the outside temperature and the remaining number of products.

[Brief description of drawings]

FIG. 1 is a diagram showing a temperature change in a refrigerator.

FIG. 2 is a diagram showing a change in temperature of a refrigerator when the sales frequency is high.

FIG. 3 is a diagram showing a change in temperature of a refrigerator when the sales frequency is low.

FIG. 4 is a diagram showing a temperature change in the heating chamber when the sales frequency is high.

FIG. 5 is a diagram showing a temperature change of the heating chamber when the sales frequency is low.

FIG. 6 is a diagram showing a temperature change in the cooling box when the temperature difference between the inside temperature and the outside air temperature is large.

FIG. 7 is a diagram showing a temperature change in the cooling box when the temperature difference between the inside temperature and the outside air temperature is small.

FIG. 8 is a diagram showing a temperature change in a refrigerator when a large number of products are stored.

FIG. 9 is a diagram showing a change in temperature of a refrigerator when the number of stored products is small.

FIG. 10 is a control block diagram showing one embodiment of the power saving device of the first invention.

11 is a flowchart showing the control operation of the refrigerator in the apparatus of FIG.

FIG. 12 is a flowchart showing the control operation of the heating chamber in the apparatus of FIG.

FIG. 13 is a control block diagram showing an embodiment of the power saving device of the second invention.

FIG. 14 is a flowchart showing the control operation of the refrigerator in the apparatus of FIG.

FIG. 15 is a control block diagram showing one embodiment of a power saving device of the third invention.

16 is a flowchart showing the control operation of the refrigerator in the apparatus of FIG.

[Explanation of symbols]

 1 Product Storage 2 Heater 3 Internal Temperature Sensor 4 Evaporator 5 Compressor 6 Valve 7 On / Off Temperature Setting Section 8 Clock 9 Temperature Gradient Calculation Section 10 Sales Frequency Determination Section 11 On / Off Temperature Shift Section 12 Drive Control Circuit 13 Outside Air Temperature Sensor 14 Out of Stock Number detector

Claims (3)

[Claims] 1. A compressor (5) for condensing a refrigerant, a valve (6) for guiding the condensed refrigerant to an evaporator in a refrigerator, a heater (2) for heating the inside of the refrigerator, and an inside for detecting the temperature inside the refrigerator. Temperature sensor
(3) By comparing the internal temperature with the preset ON temperature Ton and OFF temperature Toff, the compressor
(5) or drive control circuit for controlling heater (2) on / off
A power saving device for a vending machine comprising (12), wherein a clock (8) for measuring the time, and a refrigerator temperature and time obtained from the refrigerator temperature sensor (3) and the clock (8) A temperature gradient detecting section (9) for detecting a gradient of temperature change, and a sales frequency determining means for determining whether the sales frequency is high or low by comparing the detected temperature gradient with a reference temperature gradient value.
(10), when it is determined that the sales frequency is low, the above-mentioned ON temperature Ton
A power-saving device for a vending machine, comprising: an on-off temperature shift unit (11) for shifting an off-temperature Toff for power-saving operation. 2. The power saving device for a vending machine according to claim 1, further comprising an outside air temperature sensor (13) for detecting an outside air temperature, and based on a difference between the outside air temperature and the on temperature Ton and the off temperature Toff. A power saving device for a vending machine, which is characterized by correcting the reference temperature gradient. 3. The power saving device for a vending machine according to claim 1, further comprising a product remaining number detection unit (14) for detecting a product remaining number, and correcting the reference temperature gradient based on the product remaining number. Power saving device for vending machines.