JPH11173728A - Constant temperature device for storage - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a constant temperature device for storage of agricultural products, etc., which can maintain the optimum storage temperature not only when the ambient temperature is higher than the optimum storage temperature but also when it is lower than that, and can also prevent the chilled air within a warehouse from flowing out upon opening and closing of the door. SOLUTION: In a constant temperature device for storage, the cooling means keeps the interior of a warehouse constant, by controlling a cooling system 2, based on the temperature detected by a thermistor 7 for detection of the temperature within the warehouse. Then, when the ambient temperature is lower than the objective temperature within the warehouse as in, for example, winter season, the heating system is operated to keep the temperature within the warehouse at objective temperature. A switch device 5 switches either the cooling system 2 or the heating system 4 to operate, based on the temperature detected by a thermistor 9 for detection of ambient temperature. Furthermore, this constant temperature device for storage is provided with a partition curtain inside the door for storage or takeout so as to prevent the leakage of chill or warm air when the door is opened.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a thermostatic device for storage, and more particularly, it can maintain an optimum storage temperature even when an ambient temperature is lower than the optimum storage temperature, and can reduce power consumption. The present invention relates to a thermostat for storing agricultural products and the like.

[0002]

2. Description of the Related Art A conventional low-temperature storage has a compressor-type cooling system, and by controlling this,
The storage was cooled and the target temperature was maintained. However, for example, under the condition that the ambient temperature is 5 ° C. or less in winter, the optimum storage temperature of potatoes and the like cannot be maintained at 10 to 15 ° C.

In a conventional low-temperature storage, as shown in FIG. 6, cold air in the storage flows out when the door is opened and closed.
Energy efficiency was poor. In particular, the low-temperature storage for agricultural products has a door with a large opening area, so that the loss of cold air leakage has been a problem.

[0004]

In the cold district or winter season, it is desired by agricultural producers to commercialize a thermostat for storing agricultural products which not only stores at a constant temperature but also temporarily stores harvested agricultural products. Was. Also, to prevent cold air from flowing out of the storage when opening and closing the door, to save power,
It was desired to reduce noise.

[0005] In view of the above, the present invention provides a constant temperature storage device for agricultural products or the like which can maintain the optimum storage temperature not only when the ambient temperature is higher than the optimum storage temperature but also when it is low. The purpose is to:

Another object of the present invention is to provide a constant temperature storage device for storing agricultural products and the like, which can prevent cold air from flowing out of the refrigerator when the door is opened and closed, thereby saving power.

[0007]

According to the present invention, there is provided a thermostat for storage comprising a cabinet, a door for storing and taking out, and a means for keeping the inside at a constant temperature, wherein the means for keeping the inside at a constant temperature is provided. Cooling means for controlling the inside of the thermostat to maintain the target temperature based on the detected temperature in the thermostat, and heating control of the interior of the thermostat to maintain the target temperature based on the detected temperature in the thermostat. Heating means, means for detecting an ambient temperature outside the thermostat, and operating the cooling means when the detected ambient temperature is equal to or higher than a set temperature, and heating when the detected ambient temperature is equal to or lower than the set temperature. Switching means for operating the means.

[0008] The cooling means corresponds to the cooling system 2 and the cooling system control device 1.
Controls the cooling system 2 including the cooling compressor based on the temperature detected by the in-compartment temperature detection thermistor 7 to maintain the inside of the compartment at a target constant temperature.
On the other hand, when the ambient temperature is lower than the target temperature in the refrigerator, for example, in winter, the present invention operates the heating means in order to keep the temperature in the refrigerator at the target temperature. That is, the heating means corresponds to the heating system 4 and the heating system control device 3, and the heating system control device 3 controls the heating system 4 based on the inside temperature detected by the inside temperature detection thermistor 8. , The interior of the refrigerator is maintained at a target temperature higher than the ambient temperature. The switching device 5 switches to operate either the cooling system 2 or the heating system 4 based on the temperatures detected by the ambient temperature detecting thermistor 9 and the ambient temperature detecting device 6.

In the constant temperature storage device according to the present invention, the switching of the operation of the cooling unit and the heating unit by the switching unit is performed by switching a power supply to the cooling unit and the heating unit. .

Further, the storage constant temperature device of the present invention is characterized in that a partition curtain is provided inside the door to prevent leakage of cool air at the time of cooling or warm air at the time of heating when the door is opened. (Claim 3).

[0011]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS FIG. 1 shows an entire configuration of a thermostat for storing agricultural products to which the present invention is applied. In the figure,
1 is a cooling system control device, 2 is a cooling system, 3 is a heating system control device, 4 is a heating system, 5 is a switching device, 6 is an ambient temperature detecting device, 7 and 8 are thermistors for detecting the temperature inside the refrigerator, and 9 is a thermistor. 3 shows a thermistor for detecting an ambient temperature. Further, a cooling compressor, a heating device, a control device therefor, and the like can be provided at appropriate positions, but FIG.

The cooling system controller 1 controls the cooling system 2 including the cooling compressor based on the temperature detected by the temperature detecting thermistor 7 so as to maintain the inside of the refrigerator at a target constant temperature. I have. This is to keep the inside of the refrigerator at a constant temperature by cooling the refrigerator when the ambient temperature is higher than the target temperature T1 ° C. For example, control can be performed such that when the temperature detected by the thermistor 7 is higher than the set target temperature T1 ° C., the compressor of the cooling system is turned on, and when it is low, it is turned off.

On the other hand, when the ambient temperature is lower than the internal target temperature T2 ° C., for example, in winter, the present invention provides:
The heating system is operated to keep the temperature in the refrigerator at the target temperature T2 ° C. That is, the heating system control device 3 controls the heating system 4 based on the internal temperature detected by the internal temperature detecting thermistor 8 to maintain the internal temperature at the target temperature T2 ° C. higher than the ambient temperature. For example,
When the temperature detected by the thermistor 8 is lower than the set target temperature T2 ° C., it is possible to perform control such that the heating wire heater of the heating system is turned on, and when it is high, it is turned off. The thermistors 7 and 8 for detecting the temperature in the refrigerator can be used in common, but preferably, the thermistor 7 for detecting that the temperature in the refrigerator is higher than the set temperature is provided at the upper part of the refrigerator and at a lower temperature. The thermistor 8 to be detected is provided at a central portion or a lower portion in the refrigerator.

The switching device 5 switches to operate either the cooling system 2 or the heating system 4 based on the temperatures detected by the thermistor 9 for detecting the ambient temperature and the ambient temperature detecting device 6. In the illustrated example, the power supply is switched to connect the power supply to the cooling system 2 when the ambient temperature is higher than the set temperature T ° C. On the contrary, when the ambient temperature is lower than the set temperature T ° C., the power supply is supplied to the heating system 4. Connect. It is desirable that the set target temperature has a relationship of T2 ° C <T ° <T1 ° C in order to avoid frequent starting and stopping of the cooling system 2 and the heating system 4. For the same reason, it is preferable that the set temperature when operating the cooling system 2 based on the ambient temperature is set to, for example, 15 ° C., and the set temperature when operating the heating system is set to be higher than, for example, 10 ° C. .

FIG. 2 shows a cooling system 2 according to the ambient temperature.
FIG. 3 shows an example of an electric circuit for switching the heating system 4 in detail. After being stepped down by a transformer from a commercial power supply of AC100V, the voltage is rectified by a full-wave rectifier to be a pulsating DC voltage. After this DC voltage is smoothed by the capacitor C1, it is controlled to a constant voltage by the constant voltage circuit Reg.

This output voltage is applied to a Zener diode ZD, and a constant DC voltage is taken out from both ends thereof. This voltage is further divided by the ratio of resistors R6 and R3 to obtain a constant reference voltage. , Are applied to the + input of the comparator. On the other hand, a voltage obtained by dividing a constant DC voltage at both ends of the zener diode by a resistance ratio between the resistor R2 and the thermistor 9 is applied to the negative input of the comparator. The thermistor 9 is for detecting an ambient temperature, and may be any element other than the thermistor as long as its resistance value changes with a change in temperature.

The output of the comparator is applied to the base of the transistor Tr through the resistor R4. Transistor Tr
Is connected to the coil of the relay, and the other is connected to the output of the constant voltage circuit Reg. Then, a relay coil induced voltage discharging diode is connected in parallel to the coil of this relay. The common side contact of this relay is connected to one of the AC 100V power supplies. The two contacts, which are switched in response to the operation of the relay and come and go with the common side contact, are connected to the compressor and the other to the heating device. The illustrated relay shows the time of relay operation.

In this circuit, the thermistor 9 has a negative temperature coefficient whose resistance value decreases substantially linearly with a rise in temperature. Further, the comparator functions as a determination circuit that determines whether the ambient temperature is lower or higher than the set temperature. Now, it is assumed that the ambient temperature is lower than the target temperature T ° C. set by adjusting the variable resistor R6. The resistance value of the thermistor 9 having a negative temperature coefficient is a large value. Therefore, the negative input of the comparator is larger than its positive input. Then, the output of the comparator is not output, the transistor Tr does not operate, and therefore, the relay does not operate. When the relay is not operated, the relay common contact is configured to be connected to the heating device side. Thereby, the power supply is connected to the heating device.

On the other hand, it is assumed that the ambient temperature is higher than the set target temperature T ° C. Thermistor 9
Becomes smaller, the minus side of the comparator becomes smaller than its plus side, and an output is generated from the comparator. This allows
The relay operates through the transistor Tr, and the AC power supply is connected to the compressor through the operating contact.

As an example of the cooling system shown in FIG.
For example, the one shown in FIG. 3 can be used.
In the figure, 15 is an electrically driven compressor, 16
Is a refrigerant pipe, 17 is a condenser, 18 is a decompression device, and 19 is an evaporator functioning as a cooler. The refrigerant compressed by the electrically driven compressor 15 flows through the refrigerant pipe 16, radiates heat in the condenser 17, expands in the pressure reducing device 18, and forms a refrigeration cycle in which heat is absorbed by the evaporator 19.

As an example of the heating system shown in FIG. 1, for example, a heating wire heater can be embedded in an inner wall or a floor of a refrigerator, or the air heated by the heating wire heater can be circulated by a fan. Alternatively, as shown in FIG. 4, a heat pump type in which a cooling system and a heating system are integrally combined can be used.

In FIG. 4, 15 is an electrically driven compressor, 18 is a decompression device, 19 is an evaporator, 20 is a heat exchanger, 21 and 22 are check valves, 23 is a radiator, and 24 is a four-way valve. . A four-way valve 24 is provided between the discharge side and the suction side of the compressor 15 so that the compressor 15
Is discharged by the four-way valve 24 to the heat exchanger 20 acting as a condenser, and from there,
Flows through the evaporator 19 and the check valve 22 via the pressure reducing device 18,
The flow returns to the compressor 15 via the four-way valve 24. Thus, at the time of cooling, it functions similarly to the cooling system shown in FIG. 3 described above.

At the time of heating, the refrigerant discharged from the compressor 15 flows toward the radiator 23 installed on the inner wall surface, the floor surface, etc. of the refrigerator by the four-way valve 24 to heat the interior of the refrigerator. It flows via the stop valve 21 to the pressure reducing device 18 and from there to the heat exchanger 20 which functions as an evaporator, and returns to the compressor 15 via the four-way valve 24.

As described above, the ambient temperature is set to the target temperature T.degree.
When the temperature is higher, the cooling system is operated, and when the temperature is lower, the heating system is operated, so that an appropriate temperature can be controlled.

FIG. 5 is a diagram for explaining an improvement of a constant temperature storage for storing agricultural products to which such a temperature control device in a storage is applied.
In the figure, 13 is a constant temperature cabinet, 14 is a partition curtain, 11 is a curtain rail, 12 is a curtain hook, and 10 is a constant temperature cabinet door. In the cabinet, shelves and partitions can be provided for storing agricultural products, but are not shown. The cabinet is provided with a door 10. The constant temperature storage is provided with a partition curtain 14 for preventing cold air from leaking. The partition curtain 14 is provided immediately inside the door 10 when the door 10 is closed so that when the door 10 is opened for storing or removing agricultural products, the cool air (or the warm air generated during heating) in the cabinet does not leak. Provided. The partition curtain 14 can be mounted by means of a curtain rail 11 and a curtain hook 12 for mounting it and sliding it in the lateral direction. Alternatively, it can be detachably attached using an appropriate means such as a magnet or a hook. The curtain rail 11 is a cabinet 13
Is mounted on the front upper side so as not to disturb the opening and closing of the door 10. The storage and removal of agricultural products can be performed by dividing the partition curtain into left and right parts at the center, and folding the partition curtain from between or from below the curtain.

As the curtain material, any material can be used as long as it is a flexible sheet member. Preferably, a transparent or translucent plastic material, polyurethane, polyester, polyvinyl chloride or the like is used. it can.

[0027]

According to the present invention, in the constant temperature storage device, the cooling means is operated when the detected ambient temperature is higher than the set temperature, and the heating means is operated when the detected ambient temperature is lower than the set temperature. With this configuration, it is possible to maintain the optimum storage temperature not only when the ambient temperature is higher than the optimum storage temperature but also when it is low. Also,
By providing a partition curtain inside the door of the storage thermostat, it is possible to prevent the leakage of cool air during cooling or warm air during heating when the door is opened,
This has the effect of saving power and reducing noise.

[Brief description of the drawings]

FIG. 1 shows an overall configuration of a thermostat for storing agricultural products to which the present invention is applied.

FIG. 2 is a diagram illustrating an example of an electric circuit that switches between a cooling system 2 and a heating system 4 according to an ambient temperature.

FIG. 3 is a diagram illustrating a cooling system that can be used in the present invention.

FIG. 4 is a diagram exemplifying a heat pump type in which a cooling system and a heating system that can be used in the present invention are combined.

FIG. 5 is a diagram showing a configuration of a thermostat for storing agricultural products to which the present invention is applied.

FIG. 6 shows a prior art cold storage.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Cooling system controller 2 Cooling system 3 Heating system controller 4 Heating system 5 Switching device 6 Ambient temperature detecting device 7 Thermistor for detecting the temperature in a refrigerator 8 Thermistor for detecting the temperature in a refrigerator 9 Thermistor for detecting the ambient temperature 10 Door 11 Curtain rail 12 Curtain hook 13 Cabinet 14 Partition curtain 15 Compressor 16 Refrigerant piping 17 Condenser 18 Decompression device 19 Evaporator 20 Heat exchanger 21 Check valve 22 Check valve 23 Radiator 24 Four-way valve

Continued on the front page (72) Inventor Mikio Yoshino 3 Hayakawa, Hayakawa, Nitta-machi, Nitta-gun, Gunma Prefecture Inside the Nitta Plant of Sawafuji Electric Co., Ltd. No. 3 Sawafuji Electric Co., Ltd. Nitta Plant

Claims (3)

[Claims] 1. A constant temperature storage device comprising a cabinet, a door for storing and taking out, and a means for keeping the inside at a constant temperature, wherein the means for keeping the constant temperature is based on the detected temperature inside the constant temperature device. Cooling means for controlling the cooling of the inside of the constant temperature apparatus so as to maintain the target temperature; heating means for controlling the heating inside the constant temperature apparatus so as to maintain the target temperature based on the detected temperature in the constant temperature apparatus; Means for detecting an ambient temperature; and switching means for operating the cooling means when the detected ambient temperature is equal to or higher than a set temperature and operating the heating means when the detected ambient temperature is equal to or lower than the set temperature. A constant temperature storage device for storage. 2. The switching of the operation of the cooling unit and the heating unit by the switching unit is performed by switching a power supply to the cooling unit and the heating unit.
2. The storage thermostat according to claim 1. 3. The door according to claim 1, wherein a partition curtain is provided inside the door to prevent leakage of cool air at the time of cooling or warm air at the time of heating when the door is opened.
A storage thermostat as described.