JP3121879B2 - Vending machine defrost control device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a vending machine (vending machine) in which a plurality of (up to two in this example) commodity storages can be switched and cooled by one cooler (evaporator, also simply referred to as evaporator). ) For controlling the defrosting of the cooler.

[0002]

2. Description of the Related Art FIG. 1 is a block diagram of a cooling system of a vending machine according to an embodiment of the present invention. Conventionally, the temperature detecting thermistors 5-1 and 5-2 shown in FIG. 1 are not provided.
FIG. 1 shows an example of a vending machine having four cooling or heating chambers (storage) for storing goods. That is, R1 to R4 are sequentially referred to as the inside of the left compartment, the inside of the middle compartment, the inside of the middle right compartment, and the inside of the right compartment in these four chambers. Next, 1 is a refrigerator (abbreviated as MC), 3-
Reference numerals 1 and 3-2 denote left and right evaporators as evaporators, respectively. 2-1 and 2-2 are refrigerators (MC) 1 respectively.
The solenoid valves open and close the refrigerant supplied to the left evaporator 3-1 and the right evaporator 3-2, and are also referred to as a left valve and a right valve, respectively.

A shutter 4-1 opens and closes an opening on a partition wall between the left compartment R1 and the middle compartment R2 by a solenoid (not shown), and a left engine 3-1 opens the left compartment when the shutter 4-1 is opened. The inner chamber R1 and the inner chamber R2 are cooled, and the shutter 4
At the time of closing -1, only the left compartment R1 is cooled. Similarly, 4-
Reference numeral 2 denotes a shutter for opening and closing the openings on the partition walls of the middle right inside R3 and the right inside R4.
, The two chambers R3 and R4 or only the chamber R3 are cooled, respectively. Reference numerals 7-1 to 7-4 denote thermistors for detecting the temperatures in the refrigerators R1 to R4, respectively. The interiors R1 to R4 are each provided with a heater (not shown) for heating the interior. Reference numeral 6 denotes a cooling / heating control device that controls the temperature of each of the compartments R1 to R4 to a predetermined temperature by using the above-described units.

When the operation of the evaporators 3-1 and 3-2 is continued, moisture in the air to be cooled is attached as frost to the evaporator as time passes.
Since the cooling capacity of the evaporator is reduced, in this example, the conventional cooling / heating control device 6 uses the cooling device 15 every 8 hours.
The frost prevention (defrosting) was performed by forcibly turning off the MC1 for a minute.

[0005]

In the conventional vending machine having the above-described structure, the evaporator defrosting control method assumes that if the refrigerator (MC) is turned off for 15 minutes every 8 hours, the evaporator can be defrosted. It was a control system. However, in this type of vending machine, the condition inside the refrigerator, which is the object of cooling of the evaporator, fluctuates greatly.
Just turning off C does not completely remove the defrost,
By the repetition of such defrosting, the eva was frozen in the end, and the inside of the refrigerator could not be cooled. Therefore, it is conceivable to increase the frequency of defrosting or to increase the OFF time of the refrigerator so that reliable defrosting can be performed irrespective of fluctuations in all refrigerator conditions. Problem arises. Therefore, an object of the present invention is to provide a defrosting control device for a vending machine which can solve such a problem.

[0006]

In order to solve the above-mentioned problems, a defrosting control device according to the present invention reduces the number of merchandise storages to be cooled by one evaporator (e.g., left evaporator 3-1). In a vending machine capable of changing the switching (via a shutter 4-1 or the like), a means (such as a thermistor 5-1) for detecting the temperature of the evaporator and the supply of the refrigerant to the evaporator are performed at predetermined time intervals (for example, every eight hours). A defrost command for starting the defrosting by the air inside the refrigerator is output, and it is determined whether a predetermined time (15 minutes or the like) has elapsed from the start of the defrosting. Control means for comparing the temperature with a predetermined value and continuing the defrosting when the detected temperature is equal to or lower than the predetermined value.

[0007]

A thermistor is provided for each evaporator to detect the evaporator temperature. The control temperature of the evaporator is set in advance. Then, for example, after the elapse of 15 minutes of defrosting every 8 hours, if the temperature of the evaporator is equal to or lower than the set temperature, the MC is continuously stopped and defrosting is performed.

[0008]

Next, an embodiment of the present invention will be described with reference to FIGS. In the present invention, a thermistor 5 for detecting the temperature of the evaporator is provided on each of the left evaporator 3-1 and the right evaporator 3-2 in FIG.
-1 and 5-2 are attached. In addition, the cooling of the present invention
The set temperature at the end of the defrosting of the eva is input to the heating control device 6 in advance. FIG. 2 shows a flowchart of the defrosting control for the left evaporator 3-1 of the cooling / heating control device 6 of the present invention. Next, FIG. 2 will be described with reference to FIG. Note that S1
Symbols S5 indicate steps in FIG. That is, the cooling / heating control device 6 receives a defrosting command to turn off the MC1 every eight hours for 15 minutes from the main control unit (not shown) of the vending machine, and turns off the MC1 (S1, S2). Then, when the defrost command is released after the elapse of 15 minutes, the cooling / heating control device 6 detects the temperature of the left evaporator 3-1 via the thermistor 5-1 (S3). If the temperature is equal to or lower than the set value (branch Y), the defrosting of the left evaporator has not yet been completely achieved, and the MC1 or the left valve 2-1 is subsequently turned off.
Then (S4), defrosting is continued (return to S3). When the evaporator temperature becomes equal to or higher than the set value (S3, branch N), it is determined that the defrost has been performed, the defrost is released, the MC1 and the left valve 2-1 are both turned on, and the operation returns to the normal operation (S5). Note that the above defrost control is similarly applied to the right eva 3-2.

[0009]

According to the present invention, there is provided a vending machine in which the number of merchandise storages to be cooled by one evaporator (such as the left evaporator 3-1) can be changed (via the shutter 4-1 or the like). Means for detecting the temperature of the evaporator (such as thermistor 5-1); and outputting a defrosting command for starting the defrosting by the air in the refrigerator by cutting off the supply of the refrigerant to the evaporator every predetermined time (for example, 8 hours). Then, it is determined whether a predetermined time (eg, 15 minutes) has elapsed from the start of the defrosting. If the predetermined time has elapsed, the temperature detected by the temperature detecting means is compared with a predetermined value. Is provided with a control unit for continuing the defrosting, so that the frost can be completely defrosted every eight hours.

[Brief description of the drawings]

FIG. 1 is a configuration diagram of a vending machine cooling system as a cooling / heating control device according to an embodiment of the present invention.

FIG. 2 is a flowchart of defrost control of the cooling / heating control device of FIG. 1;

[Explanation of symbols]

 R1 Left warehouse R1 Middle warehouse R1 Middle right warehouse R1 Right warehouse 1 Refrigerator (MC) 2-1 Left valve 2-2 Right valve 3-1 Left eva 3-2 Right eva 4-1 Shutter 4-2 Shutter 5-1 Left evaporator temperature detecting thermistor 5-2 Right evaporator temperature detecting thermistor 6 Cooling / heating control device 7-1 Left internal temperature detecting thermistor 7-2 Middle internal temperature detecting thermistor 7-3 Middle right 7-4 Thermistor for temperature detection in the right chamber

──────────────────────────────────────────────────続 き Continuation of the front page (56) References JP-A-61-217667 (JP, A) JP-A-63-41785 (JP, A) Fully open Showa 56-78961 (JP, U) Really open Showa 62- 164572 (JP, U) JP-A-58-179486 (JP, U) JP-A-1-102680 (JP, U) JP-B-43-4061 (JP, B2) (58) Fields surveyed (Int. Cl. ⁷ , DB name) F25D 21/00-21/02 F25D 21/06-21/12

Claims (1)

(57) [Claims] 1. A vending machine capable of changing the number of commodity storages to be cooled by one evaporator, wherein means for detecting the temperature of the evaporator, and supply of refrigerant to the evaporator is cut off at predetermined time intervals. And outputs a defrost command to start defrosting with the air in the refrigerator, determines whether a predetermined time has elapsed since the start of the defrost, and compares the detected temperature of the temperature detecting means with a predetermined value when the predetermined time has elapsed. And a control unit for continuing the defrosting when the detected temperature is equal to or lower than a predetermined value.