JPH02238275A - Clogged filter sensing device in cooler in automatic vending machine - Google Patents

Abstract

PURPOSE:To enable a positive alarm to be attained when dusts or the like are accumulated and a filter is clogged by a method wherein a first temperature for sensing a temperature within a condensor, a second temperature sensor for sensing a surrounding temperature of an evaporator and an alarm lamp are provided. CONSTITUTION:This system is provided with a first temperature sensor 11 for sensing a temperature of a condenser 5, a second temperature sensor 12 for sensing a surrounding temperature of an evaporator and an alarm lamp 13 to be tuned on when the first temperature sensor 11 indicates a temperature more than a first set temperature and the second temperature sensor 12 is less than a second set temperature. In this case, during a normal cooling load operation in which a water temperature is lower than T2 deg.C, a contact point 12a is closed and at this time when dusts are accumulated and clogged in the filter, a temperature of the condensor 5 is increased more than T1 deg.C, the contact point 11a is closed and the alarm lamp 13 is turned on. With such an arrangement, the alarm lamp 13 enables a positive alarm of clogged state in the filter.

Description

[Detailed Description of the Invention] [Industrial Application Field] This invention relates to a cooling device installed in a vending machine,
The present invention relates to a filter clogging detection device for a filter provided at an outside air intake for cooling a condenser.

[Conventional technology]

Many vending machines are equipped with a cooling device to cool products or obtain cold water. This cooling device is an evaporator,
It is well known that a refrigeration cycle is configured by a compressor, a condenser, etc., and the products and water are cooled through the evaporator. Vending machines use air-cooled condensers that liquefy the naturalized refrigerant in the evaporator, and outside air, which has been filtered to remove dirt and dust, is used as the cooling air.

[Problem to be solved by the invention]

By the way, if dirt, dust, etc. accumulate in the filter, the ventilation of outside air will be obstructed, resulting in serious problems such as a decrease in the cooling efficiency of the cooling system, an increase in power consumption, and a shortening of the lifespan of some devices. occurs.

However, in conventional cooling devices, there is no means to detect when the filter is clogged and the ventilation of outside air is obstructed, and the filter must be regularly cleaned to prevent this problem.

SUMMARY OF THE INVENTION An object of the present invention is to provide a filter clogging detection device for a cooling device that accurately warns when a filter becomes clogged due to accumulation of dirt, dust, etc.

[Means to solve the problem]

In order to achieve the above object, according to the present invention, an evaporator and a condenser constituting a refrigeration cycle together with the evaporator are disposed in the machine, and the condenser is cooled by outside air taken in through a filter. In a cooling device for a vending machine, a first temperature sensor detects the temperature of the condenser, a second temperature sensor detects the ambient temperature of the evaporator, and the first temperature sensor has a first set temperature. A filter clogging detection device is configured by including the above and a warning light that lights up when the second temperature sensor is lower than the second set temperature, and this is installed in the cooling device.

[Effect]

When the filter becomes clogged, the temperature of the condenser increases due to less outside air for cooling, which is detected by the first temperature sensor. On the other hand, the temperature of the condenser also rises when the cooling load is extremely large, such as during the initial pull-down of the cooling system, but if the temperature rise is due to this, the second
Detected by temperature sensor. Therefore, a warning light provided to be lit when the first temperature sensor is above a certain temperature and the second temperature sensor is below a predetermined temperature will accurately notify that the filter is clogged.

〔Example〕

An embodiment of the present invention will be explained based on FIGS. 1 and 2 for the case of a cooling load that obtains cold water. In the figure, first, the cooling device will be explained.

1 is a cold water tank serving as a cooling load. Reference numeral 2 denotes a cooling device, which includes a compressor 4, a condenser 5, and an evaporator 6 connected by a refrigerant pipe 3 through which refrigerant flows in the direction of the arrow. In the cooling device i11!2, the refrigerant flowing through the evaporator 6 installed in the cold water tank 1 is vaporized to cool the water. The vaporized refrigerant is compressed to high temperature and pressure by compressor 4. The refrigerant is then cooled in the condenser 5 where it is flushed with cooling outside air sent through the illustrated filter, liquefies it again, and circulates within the refrigerant pipe 3 as shown by the arrow. Water temperature of the cold water tank 1 and condenser 5
As shown in Fig. 3, during the initial pull-down to cool the water temperature in the cold water tank 1 from room temperature to the required cooling temperature, the temperature of the condenser 5 decreases because the cooling load is extremely large. It rises significantly. After that, cooling device 2
The water temperature is maintained within a predetermined temperature range. As the filter becomes clogged and gets worse,
Although the condenser 5 liquefies and circulates the refrigerant to maintain the water temperature, the temperature gradually increases due to insufficient cooling air volume.

Next, the filter clogging detection device II10 will be explained. Reference numeral 11 denotes a temperature sensor (first temperature sensor) attached to the condenser 5, which is set to close its contact 11a when the temperature of the condenser 5 is equal to or higher than Tl°C (first set temperature). Reference numeral 12 denotes a temperature sensor (second temperature sensor) installed in the wall for detecting the water temperature of the cold water tank 1 in which the evaporator 6 is installed.
The contact 12a is set to close when the water temperature is below T,'C (second set temperature). 13 is a warning light; 14 is a relay serving as a self-holding circuit for the warning light 13; 14a is a contact for the relay 14; 15 is a reset switch for canceling the lighting; 17 is a control box that accommodates the relay 14°, the reset switch 15, etc. It is.

In the above configuration, when the temperature of the condenser 5 exceeds T,'C, the contact 11a closes. However, if this temperature rise is due to an excessive cooling load, that is, at the time of initial pulldown, the water temperature is T2°C or higher and the contact 12a does not close, so the warning light 13 does not light up. The water temperature is T! The contact 12a is closed during normal cooling load operation where the cooling temperature range is maintained at a range lower than ℃.If the filter becomes clogged with dirt and dust, the temperature of the condenser 5 rises above T1℃, and the contact 12a closes. 11a closes and the warning light 13 lights up. Therefore, the warning light 13 accurately warns of clogging of the filter. Furthermore, even if the compressor 4 stops and the temperature of the condenser 5 drops and the contact 11a opens, this warning light 13 continues to light up via the self-holding circuit, and the warning light 13 continues to be lit via the self-holding circuit, and the warning light 13 continues to light up through the self-holding circuit, and the warning light 13 continues to light up through the self-holding circuit even if the compressor 4 stops and the temperature of the condenser 5 drops and the contact 11a opens. Make sure to let people know that there is a blockage. Then the filter is cleaned and the reset switch 1
5 is pressed, the light goes out and the filter clogging detection device 10 returns to its original state.

〔Effect of the invention〕

According to the present invention, in the cooling device for a vending machine, an evaporator and a condenser constituting a refrigeration cycle together with the evaporator are disposed inside the machine, and the condenser is cooled by outside air taken in through a filter. a first temperature sensor that detects the temperature of the condenser; a second temperature sensor that detects the ambient temperature of the evaporator; and a warning light that lights up when the sensor is below the second set temperature,
Since a filter clogging detection device has been configured, by installing this filter clogging detection device, it is possible to accurately detect the filter clogging, and the cooling device can be operated with low power consumption and high cooling efficiency. . It is also possible to prevent the life of some of the components of the cooling device from becoming short.

[Brief explanation of drawings]

Fig. 1 is an electric circuit diagram of a filter clogging detection device showing an embodiment of the present invention, Fig. 2 is a system diagram of a cooling device equipped with a filter clogging detection device, and Fig. 3 is a diagram showing condenser temperature and cooling load. It is an explanatory diagram for explaining the relationship with the water temperature of a certain cold water tank. 2... Cooling device, 5... Condenser, 6... Evaporator,
DESCRIPTION OF SYMBOLS 10... Filter clogging detection device, 11... (1st) temperature sensor, lla... Contact point of temperature sensor 11, 12... (2nd) temperature sensor, 12a... Temperature sensor 12 contacts, 13... warning light, T,... set temperature of temperature sensor 11, T2... set temperature of temperature sensor l2 Fig. 1 Fig. 3 Fig. 2

Claims (1)

[Claims] 1) In a cooling device for a vending machine, in which an evaporator and a condenser that together with the evaporator constitute a refrigeration cycle are disposed inside the machine, and the condenser is cooled by outside air taken in through a filter, the temperature of the condenser is The first step is to detect
and a second temperature sensor for detecting the ambient temperature of the evaporator.
and a warning light that lights up when the first temperature sensor is above a first set temperature and the second temperature sensor is below a second set temperature. A filter clogging detection device for a cooling device in a vending machine.