JP3203139B2 - Vending machine cooling system - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a cooling device mounted on a vending machine for selling goods such as canned beverages and cooling the goods.

[0002]

2. Description of the Related Art Conventionally, a cooling device shown in FIG. 4 has been known as a cooling device mounted on a vending machine for selling products such as canned beverages. The cooling device 51 includes a compressor (compressor) 60, a condenser (condenser) 61, a distributor 58, solenoid valves 57a and 57b, capillaries (capillaries) 53a and 53b, and evaporators (evaporators) 54a and 54b. And the accumulator 59
And a refrigerant pipe 56 which connects these in series and forms a closed circuit refrigeration circuit.
A refrigerant such as freon is sealed in the refrigerant pipe 56,
It is circulating in this refrigeration circuit.

[0003] With the above configuration, the capacitor 61
The refrigerant condensed and liquefied in the above is sent to the distributor 58 through the refrigerant pipe 56 and is branched into two. The solenoid valves 57a and 57b are ON (open) / OFF (close) valves, and are controlled to open and close by a controller (not shown) or the like. The capillaries 53a and 53b are a kind of capillary, and are adjusted so that the refrigerant flows evenly to the evaporators 54a and 54b on the downstream side even if the amount of refrigerant flowing through one of the two branched refrigerant pipes 56a or 56b fluctuates. . The liquid refrigerant flowing into each of the evaporators 54a and 54b is decompressed and vaporized in each of the evaporators 54a and 54b, and at this time, the latent heat of the refrigerant is removed from the evaporator and the surroundings, thereby performing cooling. Each evaporator 54a
And 54b are discharged from accumulator 59 to 1
Into one tube and sent to the compressor 60. The refrigerant is compressed by the compressor 60 and becomes a high-temperature and high-pressure gas.
The high-temperature and high-pressure gaseous refrigerant is sent to the condenser 61 and cooled and liquefied by a heat-radiating fan or the like. The liquefied refrigerant is sent to the evaporators 54a and 54b again by the refrigerant pipe 56, and is used again for cooling.

[0004] In the vending machine in which the cooling device 51 is mounted, there are provided three commodity storages (not shown) partitioned by a heat insulating partition. One is a product storage dedicated to cooling, and the two product storages have a structure capable of both cooling and heating. For this reason, the above-mentioned one product storage dedicated to cooling does not have an evaporator and has a structure in which cool air or hot air can circulate, and the evaporator 54a is provided with one of the one product storage dedicated to cooling. To cool the goods in both these goods storages. Further, the evaporator 54b is installed inside the above-mentioned commodity storage for both cooling and heating,
The product in the cooling / heating dual-use product storage is cooled.

With such a configuration, for example,
In winter, the solenoid valve 57b is closed, the supply of refrigerant to the evaporator 54b in the above-mentioned cooling / heating product storage is stopped, and a heater (not shown) is operated instead to heat one product storage. In such a manner, the circulation in the cooling only storage is cut off, and heating is performed by the heater of the storage having no evaporator. On the other hand, during the summer, both solenoid valves 57a, 57
7b is opened to supply the refrigerant to both evaporators 54a and 54b, thereby cooling the inside of the three commodity storages.

[0006]

However, in the above-described conventional vending machine cooling device, cooling is performed by flowing a refrigerant into an evaporator 54b in a heating / cooling / heating product storage, which is not used in winter. Is restarted, there is a tendency that the refrigerant tends to flow toward the evaporator 54a that is already operating, and the cooling of the evaporator 54b does not proceed easily.

The present invention has been made to solve the above problems, and has as its object to provide a cooling device for a vending machine capable of rapid cooling.

[0008]

To solve the above object, according to an aspect of the cooling device for the automatic vending machine according to the serial mounting of the invention in claim 1, each of the plurality of commodity storage chamber, a portion of the refrigeration circuit A cooling system for a vending machine in which a plurality of commodity storages are cooled independently of each other by installing a constituent evaporator, sending a refrigerant to each of the evaporators, and evaporating the refrigerant in each of the evaporators. In the apparatus, an evaporator valve which is provided on an inlet side refrigerant pipe of each of the evaporators and can be opened or closed, a temperature sensor for detecting a temperature in each of the evaporators, and each of the evaporators detected by each of the temperature sensors The temperature difference between the evaporators is determined, and when the temperature difference between the evaporators becomes larger than a predetermined value, the evaporator valve connected to the lower temperature evaporator is closed for a first predetermined time , and Elapse of the first predetermined time
Thereafter, a period until the second predetermined time elapses is between the evaporators.
And control means for controlling so as to stop the determination of the temperature difference .

[0009]

[0010]

According to the first aspect of the present invention, the temperature sensor detects the temperature in each evaporator. The control means determines a temperature difference between the evaporators, which is a difference between the temperatures in the evaporators detected by the respective temperature sensors, and determines that the temperature is low when the temperature difference between the evaporators becomes larger than a predetermined value. A closing control signal is output to the evaporator valve connected to the other evaporator. The evaporator valve that has output the closing control signal is closed for a first predetermined time. As a result, no refrigerant is supplied to the evaporator connected to the closed evaporator valve, and cooling is not performed in the evaporator for at least the first predetermined time. control
The means may include a second predetermined time after the first predetermined time has elapsed.
Until the time elapses, the determination of the temperature difference between evaporators is stopped.
Stop. During this period, for example, normal cooling control is performed.
You. Then, after the first predetermined time has elapsed, the control means
If the specified time has elapsed, the determination of the temperature difference between evaporators
To resume.

[0011]

[0012]

An embodiment of the present invention will be described below with reference to the drawings.

As shown in FIG. 1, a vending machine 100 equipped with a cooling device 1 according to one embodiment of the present invention comprises three product storages 20a, 20b, 20c partitioned by a heat insulating partition.
It has.

A cooling device 1 shown in FIG.
, A refrigerant pipe 6 as a refrigerant pipe, evaporators 4a, 4b and 4c as three evaporators, and temperature sensors 5a and 5
b, 5c and a controller 3 as control means. Each evaporator 4a-4c is arrange | positioned inside each of each goods storage 20a-20c.

The cooling device main body 2 includes a compressor, a condenser, an electromagnetic valve, and the like, which will be described later, and supplies a liquid refrigerant for cooling. The liquid refrigerant supplied from the cooling device main body 2 is sent to each of the evaporators 4a to 4c by the refrigerant pipe 6, and evaporates in each of the evaporators 4a to 4c, thereby removing latent heat of the refrigerant from the evaporator and its surroundings to store each product storage. The product G which is cooled inside independently and stored inside
To cool. The temperature sensors 5a to 5c are provided in each of the evaporators 4a to 4c, detect the temperature TE in each of the evaporators 4a to 4c, and output to the controller 3 as a temperature signal. The controller 3 receives temperature signals from the temperature sensors 5a to 5c, monitors the temperatures TEa to TEc in the evaporators 4a to 4c, and outputs a control signal to the cooling device main body 2 according to each condition.

Two of the three commodity storages 20a to 20c, for example, the commodity storages 20a and 20b, are allocated to a commodity storage dedicated to cooling the commodity G such as a canned beverage and the other one. One product storage, for example, the product storage 20c, is assigned to a product storage that performs both cooling and heating. Therefore, for example, a heater (not shown) is provided inside the product storage 20c.

With such a configuration, for example,
Evaporator 4 in the above-mentioned commodity storages 20a and 20b
The coolant is supplied to the cooling device body 2 from the cooling device body 2 at all times to cool the products, and in winter, a control signal is output from the controller 3 to the cooling device body 2 so as to cool the product.
The electromagnetic valve 7c (see FIG. 2) described later in FIG. 2 is closed, the supply of the refrigerant to the evaporator 4c in the commodity storage 20c for both cooling and heating is stopped, and a heater (not shown) is operated instead. In the summer, the controller 3 outputs a control signal to the cooling device main body 2 to open a solenoid valve, for example, 7c (see FIG. 2) described later, in the cooling device main body 2 in the summer. Then, it is possible to switch to supply the refrigerant to the evaporator 4c and also cool the inside of the product storage 20c. This product storage 20c
The switching between the heating mode and the cooling mode is performed by a changeover switch (not shown) for controlling ON / OFF of the solenoid valve 7c.

Next, a more detailed configuration of the cooling device 1 will be described with reference to FIG. As shown in the figure,
The cooling device 1 includes a compressor (compressor) 10, a condenser (condenser) 11, an electronic expansion valve 12, a distributor 8, and solenoid valves 7a and 7 serving as evaporator valves.
b, 7c, evaporators 4a, 4b, 4c, temperature sensors 5a, 5b, 5c, accumulator 9, and refrigerant pipes 6, 6a, 6b, which connect these in series and constitute a closed-circuit refrigeration circuit. 6c and the controller 3
It is provided with. A refrigerant such as freon is sealed in the refrigerant pipe 6 and circulates through the refrigeration circuit. Here, the compressor 10, the condenser 11,
Electronic expansion valve 12, distributor 8, and solenoid valve 7
a to 7c, the accumulator 9, and the refrigerant pipes 6, 6a to 6c connecting these in series form the cooling device main body 2.

The above-mentioned solenoid valves 7a to 7c and electronic expansion valve 1
A signal line to which a control signal from the controller 3 is output is connected to 2. The refrigerant pipe 6 is branched into three branches at a distributor 8 downstream of the electronic expansion valve 12,
It becomes the refrigerant pipes 6a, 6b, 6c. Refrigerant pipe 6
a is connected to a solenoid valve 7a and an evaporator 4a in series, and a refrigerant pipe 6b is connected to a solenoid valve 7b and an evaporator 4b.
However, a solenoid valve 7c and an evaporator 4c are connected in series to the refrigerant pipe 6c. The three refrigerant pipes 6a, 6b, and 6c are joined to one refrigerant pipe 6 downstream of each of the evaporators 4a to 4c, and are connected to the accumulator 9. The compressor 10 and the condenser 1
Between 1, a refrigerant pipe (not shown) with a muffler for preventing overheating of the compressor 10 may be circulated.

With the above configuration, the capacitor 11
The refrigerant condensed and liquefied in the above is sent to the electronic expansion valve 12 through the refrigerant pipe 6. The electronic expansion valve 12 is a variable valve opening type expansion valve provided with, for example, a stepping motor, and the valve opening is digitally controlled by a control signal output from the controller 3. This control signal is constituted by, for example, a pulse signal, and the valve opening is increased or decreased according to the number of pulses, and the supply amount of the refrigerant to each of the evaporators 4a to 4c is adjusted here.

The refrigerant that has passed through the electronic expansion valve 12 is sent to the distributor 8, and is branched into three. The electromagnetic valves 7a to 7c on the downstream side are valves that are controlled so as to take either an ON (open) or OFF (closed) state, and are opened and closed by a control signal from the controller 3.

The liquid refrigerant flowing into each of the evaporators 4a to 4c is decompressed and vaporized in each of the evaporators 4a to 4c. At this time, the latent heat of the refrigerant is removed from the evaporator and its surroundings to perform cooling. Each evaporator 4a-4c
The refrigerant having flowed out of the refrigerant is combined into one refrigerant pipe 6 by the accumulator 9 and sent to the compressor 10. The refrigerant is compressed by the compressor 10 and becomes a high-temperature and high-pressure gas. The high-temperature and high-pressure gaseous refrigerant is sent to the condenser 11 and cooled and liquefied by a radiation fan or the like. The liquefied refrigerant is again supplied to the evaporator 4 by the refrigerant pipe 6.
a to 4c and used again for cooling.

The temperature sensors 5a to 5c are sensors composed of, for example, thermistors or the like, and detect the temperatures TEa to TEc in the evaporators 4a to 4c, convert the temperatures to electric signals, and output the electric signals to the controller 3. The controller 3 includes a microprocessor (not shown), a ROM and a RAM, and operates according to an external operation or a control program stored in the ROM.
The ON / OFF control of the solenoid valves 7a to 7c, the valve opening degree control of the electronic expansion valve 12, and the control of other parts of the cooling device are performed.

Next, a control procedure in the controller 3 of the cooling device 1 according to the present embodiment will be described with reference to a flowchart of FIG.

First, the temperature signals from the temperature sensors of each evaporator are compared with each other, and the temperature difference between each evaporator is obtained. That is, from the temperature TEi in the evaporator i output from each temperature sensor and the temperature TEj in the other evaporator j, the controller 3 determines the temperature difference ΔTij (= evaporator temperature difference) between the evaporators for each evaporator. | TEi−TEj |: general formula). Here, || indicates an absolute value symbol. In this embodiment, since there are three evaporators 4a, 4b, 4c, the temperature difference Δ
Tij is, for each evaporator, ΔTab = | TEa−T
Eb |, ΔTbc = | TEb−TEc |, ΔTca = | TEc−TEa
| Are respectively calculated.

Next, it is determined whether or not the temperature difference ΔTij between the evaporators thus obtained is larger than a predetermined value ΔTo (step S1). as a result,
If "NO", i or j is changed, and the same determination is repeated for a combination with another evaporator. "YE
If "S", the process moves to the next step S2. If the result of step S1 is "YES", it means that the temperature TEi in a certain evaporator i is larger than the temperature TEj in another evaporator j by a value larger than a predetermined value ΔTo or the temperature TEi in a certain evaporator i. Is smaller than the temperature TEj in the other evaporator j by a value larger than the predetermined value ΔTo.

Next, in step S2, it is determined whether or not the temperature TEi of a certain evaporator is lower than the temperature TEj of another evaporator. As a result, if “YES”, it means that the temperature TEi in a certain evaporator i is smaller than the temperature TEj in another evaporator j by a value larger than a predetermined value ΔTo. That is, in this case, the temperature TEi in a certain evaporator i is sufficiently cooled and lower than the temperature TEj in another evaporator j, and the temperature difference is larger than a predetermined value ΔTo. Hereinafter, the evaporator i cooled to the lowest temperature is referred to as “minimum cooling evaporator”. In this case, the process proceeds to the next step S3.

In step S3, the controller 3 outputs a closing control signal for closing a control valve (for example, the electromagnetic valve 7a) for controlling the amount of refrigerant to the sufficiently cooled minimum cooling evaporator i (for example, the evaporator 4a). . When the closing control signal is output, the control valve (for example, the solenoid valve 7)
a) is completely closed, and the supply of the refrigerant to the evaporator having the lowest temperature among the three evaporators is stopped.

Next, the controller 3 measures the elapsed time after closing the control valve (for example, the solenoid valve 7a) (step S4), and when the first predetermined time of 5 minutes has elapsed, The opening control signal is transmitted to the control valve (for example, the solenoid valve 7).
Output to a). When the opening control signal is output, the control valve (for example, the solenoid valve 7a) is completely opened (step S).
5). Therefore, the control valve (for example, the solenoid valve 7a) is completely closed for 5 minutes from when the closing control signal is output to when the opening control signal is output. As a result, no refrigerant is supplied to the lowest cooling evaporator i (for example, the evaporator 4a), and cooling is stopped in the evaporator i for at least the five minutes.

After the release control signal is output,
The refrigerant is supplied to the lowest cooling evaporator i (for example, the evaporator 4a), and the cooling in the evaporator i (for example, the evaporator 4a) is restarted.

Next, after a lapse of the first predetermined time of 5 minutes (that is, after opening the solenoid valve (eg, the solenoid valve 7a) to the evaporator i), the controller 3 sets the second predetermined time of 10 minutes. During the period until the minute elapses, the determination of the evaporator temperature difference ΔTij (see step S1) is not performed. During this period, for example, if the temperature inside the evaporator controlled by a certain internal temperature rises above a certain temperature (for example, the upper limit temperature TU), the solenoid valve connected to the evaporator is opened. If the temperature has dropped to another specific temperature (for example, the lower limit temperature TL), "normal cooling control" such as closing an electromagnetic valve connected to the evaporator is performed (step S6). In this “normal cooling control”, the controller 3 may output a control signal to the electronic expansion valve 12 as necessary to control the valve opening.

Next, the controller 3 measures the time, and after elapse of the first predetermined time of 5 minutes and then of the second predetermined time of 10 minutes (step S7), the controller 3 measures the temperature inside the evaporator. Monitoring and temperature difference ΔTij between evaporators
Is resumed. That is, the second predetermined time corresponds to a grace period until the re-determination of the inter-evaporator temperature difference ΔTij.

If the result of the determination in step S2 is "NO", the temperature TEj in the evaporator j is determined.
Is sufficiently cooled and lower than the temperature TEi in the other evaporator i, and the temperature difference is larger than the predetermined value ΔTo. Therefore, the electromagnetic valve (for example, the electromagnetic valve 7c) leading to the evaporator j (for example, the evaporator 4c) about,
A procedure similar to the procedure after step S3 is executed.

By performing the above-described control, a cooled evaporator which is more sufficiently cooled than other evaporators and which does not need further cooling is found, and the supply of the refrigerant to the cooled evaporator is performed by the first evaporator. Since the operation is stopped only for the predetermined time of 5 minutes, a sufficient refrigerant is supplied to an uncooled evaporator (for example, the evaporator 4c) that has not been sufficiently cooled, and the uncooled evaporator can be rapidly cooled. That is, the cooling is effectively and rapidly performed in an evaporator that is installed in a cooling / heating product storage and immediately after switching from the heating mode to the cooling mode, or an evaporator in which the cooling load suddenly increases and the cooling becomes difficult. It becomes possible.

The present invention is not limited to the above embodiment. The above-described embodiment is an exemplification, and has substantially the same configuration as the technical idea described in the claims of the present invention, and any device having the same function and effect can be realized by the present invention. It is included in the technical scope of the invention.

For example, in the above-described embodiment, an example in which the number of the product storages and the evaporators is three has been described. However, the present invention is not limited to this. Any number of two or more may be used.

Further, in the above-described embodiment, an example in which the first predetermined time is set to 5 minutes and the second predetermined time is set to 10 minutes has been described. However, the present invention is not limited to this. The predetermined time and the second predetermined time may be a combination of other values. For example, an example in which the first predetermined time is 5 minutes and the second predetermined time is 5 minutes, an example in which the first predetermined time is 1 minute and the second predetermined time is 2 minutes, etc. Good .

Further, in the above-described embodiment, an example has been described in which an ON (open) / OFF (closed) control type solenoid valve is used as the evaporator valve. However, the present invention is not limited to this. An electronic expansion valve may be used. Alternatively, another type of variable opening type expansion valve may be employed instead of the stepping motor type electronic expansion valve.

Further, in the above embodiment, after the first predetermined time of 5 minutes has elapsed, the solenoid valve which is the valve for the evaporator, which has been closed for 5 minutes, is once opened (see step S5). ), But the present invention is not limited to this. For example, even if the first predetermined time has elapsed,
If the temperature inside the cooled evaporator, in which the solenoid valve is closed, is still lower than the upper limit temperature TU and cooling is unnecessary, even if the solenoid valve is once opened in step S5, the "normal cooling control" in step S6 immediately after step S6. In this case, it is irrational, and in such a case, control may be performed so that step S5 is not performed and the process proceeds to step S6.

[0040]

As described above, according to the present invention,
The control means in the cooling device stops the supply of the refrigerant to the evaporator which is more sufficiently cooled than the other evaporators for at least the first predetermined time. Sufficient refrigerant is supplied, enabling rapid cooling of the uncooled evaporator.

In addition, wasteful supply of the refrigerant to the evaporator which has already been sufficiently cooled is not performed, thereby saving energy.

When the determination is made based on the temperature in the product storage, the product storage has not yet been sufficiently cooled, but the temperature in the evaporator has been sufficiently cooled. Even if the cooling of the product storage proceeds after a lapse of time, useless cooling in the evaporator may be further promoted. In the case of the present invention, the temperature is determined based on the temperature in the evaporator. Therefore, such control does not occur and accurate control can be performed.

[Brief description of the drawings]

FIG. 1 is a block diagram showing the overall configuration of a vending machine equipped with a cooling device according to one embodiment of the present invention.

FIG. 2 is a detailed block diagram showing a configuration of a cooling device in the vending machine shown in FIG.

FIG. 3 is a flowchart showing a control procedure in a controller of the cooling device of the vending machine shown in FIGS. 1 and 2;

FIG. 4 is a block diagram showing a configuration of a conventional cooling device of a vending machine.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Cooling device 2 Cooling device main body 3 Controller 4a-4c Evaporator 5a-5c Temperature sensor 6,6a-6c Refrigerant pipe 7a-7c Solenoid valve 8 Distributor 9 Accumulator 10 Compressor 11 Capacitor 12 Electronic expansion valve 20a-20c Product storage 51 Cooling Equipment 53a, 53b Capillary 54a, 54b Evaporator 56, 56a, 56b Refrigerant pipe 57a, 57b Solenoid valve 58 Distributor 59 Accumulator 60 Compressor 61 Capacitor 100 Vending machine G Product

──────────────────────────────────────────────────続 き Continuation of the front page (72) Katsuyoshi Tajima 2-5-5 Keihanhondori, Moriguchi-shi, Osaka Sanyo Electric Co., Ltd. (56) Reference JP-A-5-258164 (JP, A) JP-A-3-172992 (JP, A) JP-A-57-48187 (JP, A) JP-A-4-113873 (JP, U) (58) Fields investigated (Int. Cl. ⁷ , DB name) F25D 11 / 00 101

Claims (1)

(57) [Claims] An evaporator constituting a part of a refrigeration circuit is installed in each of a plurality of commodity storages, and a refrigerant is sent to each of the evaporators to evaporate the refrigerant in each of the evaporators. In a cooling device of a vending machine configured to cool a plurality of product storages independently of each other, a valve for an evaporator, which is provided in an inlet side refrigerant pipe of each of the evaporators and can be opened or closed, a temperature sensor that detect the temperature of the determined temperature difference between the respective evaporators cross each temperature sensor detects a low temperature when the temperature difference between the evaporator is larger than a predetermined value The evaporator valve communicating with one of the evaporators is closed for a first predetermined time, and
The period until the second predetermined time elapses after the elapse of
A control means for controlling the determination of the temperature difference between the evaporators to stop.
Cooling device for an automatic vending machine, characterized in that it comprises a stage, a.