JPH0510970U - Refrigerator for cold storage vehicles - Google Patents

Abstract

(57) [Summary] [Purpose] Efficiently cool the cargo in the refrigerator according to the pre-cooling condition in the "refrigerator for cold storage vehicles". [Structure] A heat detection sensor 30, such as a thermopile infrared sensor, which detects a pre-cooling state of a package, which is recognized as a temperature difference between the temperature inside the package and the temperature of the package, is attached to a ceiling portion inside the luggage compartment 10. The CPU 32 retrieves desired air volume data from the storage unit 33 based on the output of the heat detection sensor 30, and the air flow rate control unit 35 reduces the air flow rate if the package is pre-cooled sufficiently, and increases the air flow rate if the package is not pre-cooled. Such a voltage is applied to the evaporator fan 13. [Effect] It is possible to efficiently cool the inside of the refrigerator and reduce the power consumption of the device.

Description

[Detailed description of the device]

[0001]

[Industrial applications]

 The present invention relates to a refrigerator for a refrigerating vehicle capable of efficiently cooling a load in the refrigerating compartment of the refrigerating vehicle according to the pre-cooling state.

[0002]

[Prior Art]

 Generally, fresh foods and the like need to be kept at the optimum temperature for their transportation, so cold trucks are used for transportation. As an example of this cold storage car, there is one disclosed in Japanese Patent Publication No. 62-210373, and a general structure of a general cold storage car is as shown in FIG.

A cooling unit 11 that constitutes a part of a refrigerator is provided in a luggage compartment 10 in which a cold-insulated product is mounted. In the cooling unit 11, an evaporator 12 that cools the air in the luggage compartment 10 and a blower 13 that circulates the air in the luggage compartment 10 through the evaporator 12 as shown in the figure are built in. The cooling unit 11 also has a built-in suction temperature sensor 14 that detects the temperature of the air immediately before it is sent to the evaporator 12. The temperature detected by this sensor 14 is the inside temperature of the inside of the operating chamber 15. It is input to the control device 16 arranged in. The control device 16 controls the operation of the compressor 17 which supplies the refrigerant to the evaporator 12 based on the internal temperature. The heat absorbed through the evaporator 12 is radiated by a heat radiating unit 18 provided outside the vehicle. A condenser 19 and a blower 20 are built in the heat dissipation unit 18. It should be noted that loading and unloading of luggage in the luggage compartment 10 is performed through the door 21.

FIG. 8 is a schematic configuration diagram of a cooling system and a control system of the refrigerator of the cold storage vehicle. The evaporator 12 and the condenser 19 are mutually connected via a compressor 17 and a flow control element 22 such as a liquid tank. The air cooled by the evaporator 12 is blown into the luggage compartment 10 by the evaporator fan 13 rotating at a constant air volume, that is, at a constant rotation speed. Heat dissipation from the condenser 19 is forcibly performed by the capacitor fan 20. The controller 16 controls on / off of the compressor 17 and operation control of the evaporator fan 13 and the condenser fan 20. For example, when the desired temperature in the luggage compartment 10 is set by the temperature setter 23 and the refrigerator start switch 24 is turned on, the evaporator fan 13 starts to rotate at a constant rotation speed, and the compressor 17 keeps the set temperature and the storage temperature. On-off control is performed based on the temperature difference from the internal temperature.

[0005]

[Problems to be solved by the device]

 However, in such a conventional refrigerator for a cold-insulated vehicle, the amount of air blown by the evaporator fan 13 is always constant regardless of the pre-cooling state of the luggage stored in the luggage compartment 10. There will be a problem.

That is, conventionally, the compressor 17 is always operated at the maximum capacity and the evaporator fan 13 is also operated at the maximum air volume regardless of whether or not the load accommodated in the luggage compartment 10 is previously cooled. However, if the load is not pre-cooled, the temperature of the load can be reduced quickly by exerting the maximum freezing / freezing capacity of the refrigerator, but if the load is pre-cooled, the refrigerating capacity becomes excessive and power consumption is pointed out. I arrived. However, it has been clarified that the amount of external heat entering the luggage compartment 10 increases as the air flow increases, so even if the air flow rate is maximized, the cargo inside the warehouse is not necessarily cooled efficiently. Increasing the air volume more than necessary is a problem from the perspective of cooling efficiency. Furthermore, since the evaporator fan 13 is always operated at maximum capacity, it can be said that it has a great impact on its life. It can be said that the use of refrigerated vehicles is quite severe, unlike ordinary passenger cars, so it is important to solve the above problems.

The present invention has been made in order to solve the above problems of the prior art, and is for a cold-insulated vehicle capable of efficiently cooling the cargo in the luggage compartment according to its pre-cooling state. The purpose is to provide a refrigerator.

[0008]

[Means for Solving the Problems]

 The present invention for achieving the above object includes an evaporator for cooling air in a refrigerating compartment, a blower for circulating air in the refrigerating compartment through the evaporator, and a pre-cooling unit for detecting a pre-cooling state of luggage in the refrigerating compartment. An air flow rate for calculating an optimum air flow rate by the blower so that the load in the refrigerating compartment is efficiently cooled based on the state detecting means and the pre-cooling state of the load in the refrigerating compartment detected by the precooling state detecting means. And a calculation means.

[0009]

[Action]

 The present invention configured as described above operates as follows. When the pre-cooling state detecting means detects the pre-cooling state of the baggage in the refrigerating room, that is, the temperature deviation between the temperature in the refrigerating room and the temperature of the baggage, the air flow rate calculating means detects the baggage in the refrigerating room based on the pre-cooling state of the baggage. Calculate the optimum blow rate by the blower so that it can be cooled efficiently. Then, the blower is operated at a rotation speed capable of sending out this optimum amount of blown air.

Therefore, when the temperature deviation is large, the air flow amount is large, and when the temperature deviation is small, the air flow amount is small, and the air flow amount suitable for the pre-cooling state of the cargo in the refrigerating compartment is secured. Therefore, in addition to improving the cooling efficiency inside the refrigerator, it is possible to reduce power consumption and improve the durability of the blower.

[0011]

【Example】

 An embodiment of the present invention will be described below in detail with reference to the drawings. FIG. 1 is a schematic configuration diagram of a refrigerator for a refrigerating vehicle according to the present invention, FIG. 2 is a control block diagram around a controller of the refrigerator for a refrigerating vehicle, and FIG. 3 is a mounting position of a heat detection sensor. It is a figure. The same members as those shown in FIGS. 7 and 8 are designated by the same reference numerals, and the description thereof is partially omitted.

In the figure, the temperature setting device 23 is for setting the cooling temperature in the luggage compartment 10, and the signal from this is output to the CPU described later as a temperature setting signal. The suction temperature sensor 14 is provided in the cooling unit 11 and detects the air temperature immediately before being sucked into the evaporator 12, and the detected temperature is output to the CPU, which will be described later, as the internal temperature. The heat detection sensor 30 detects the pre-cooling state of the cargo in the luggage compartment 10, that is, the temperature difference (ΔT ₂ ) between the temperature inside the cargo compartment and the temperature of the luggage in the cargo compartment 10 as the pre-cooling state detecting means. As shown in Fig. 3, it is attached to the ceiling of the luggage compartment 10. The heat sensor 30 is preferably a so-called thermopile infrared sensor. This thermopile infrared sensor joins a hot junction that absorbs infrared rays and the temperature rises, and a cold junction that is at the ambient temperature, and generates a thermoelectromotive force between both junctions according to the temperature difference between them. The thermocouple is piled up to detect infrared rays emitted from an object having a temperature higher than its own ambient temperature. For example, if a luggage that has not been pre-cooled is stored in the luggage compartment 10, the hot junction of the sensor 30 detects infrared rays from the luggage and the temperature rises, while the cold junction is the ambient temperature of itself, that is, the inside of the warehouse. Because of the temperature, a potential difference commensurate with the temperature difference (ΔT ₂ ) between the temperature of the load and the temperature inside the refrigerator is generated between the two contacts. This voltage is output to the CPU, which will be described later, and is recognized as the pre-cooling state of the cargo in the luggage compartment 10. Depending on the case, a plurality of heat detection sensors 30 may be arranged in the luggage compartment 10 in order to improve the detection accuracy of the pre-cooling state of the cargo in the warehouse. The switch 24 is for starting the refrigerator.

The control device 31 is provided with a CPU 32 that mainly performs calculations related to the amount of air blown in the luggage compartment 10. The CPU 32 is provided with a storage unit 33. The storage unit 33 stores the temperature difference (ΔT ₁ ) between the set temperature and the internal temperature of the refrigerator, the compressor control data regarding the ON / OFF operation of the compressor 17, and the heat detection sensor 30. The output voltage and the air volume data relating to the air volume blown by the evaporator fan 13 are stored. Although the storage unit 33 is illustrated as being built in the CPU 32 in the figure, it may be connected to the CPU 32 as an independent storage device. Further, inside the control device 31, there are provided a condenser fan control unit 34, an air flow rate control unit 35, and a compressor control unit 36, which control the operation of an external device based on a signal from the CPU 32. The condenser fan control unit 34 controls the on / off operation of the condenser fan 20. The air flow rate control unit 35 controls the rotation speed of the evaporator fan 13 so as to realize the optimum air flow rate calculated by the CPU 32. Since it is preferable that the control of the rotation speed is performed steplessly, the current flowing through the fan 13 is controlled by a semiconductor control element such as a power transistor. The compressor control unit 36 controls on / off of the compressor 17 based on the temperature inside the cold storage detected by the suction temperature sensor 14. The air flow rate calculating means is composed of the CPU 32 and the air flow rate control unit 35.

The present apparatus having the above-described configuration operates as follows according to the flowchart shown in FIG. First, when the switch 24 is turned on and the program is activated, the CPU 32 causes the set temperature set by the temperature setter 23, the inside temperature detected by the suction temperature sensor 14 and the heat detection sensor 30, and the pre-cooling of the inside package to be pre-cooled. Each of the states is input (S 1). Next, the CPU 32 calculates a temperature deviation ΔT ₁ between the set temperature and the internal temperature (S2), and controls the compressor control unit 36 based on the compressor control data as shown in FIG. The on / off control of the compressor 17 is performed via the. That is, as shown in the figure, the compressor 17 is turned on when the temperature difference ΔT ₁ between the set temperature and the internal temperature exceeds + 1 ° C, and is turned off when it exceeds -1 ° C. By turning on and off in this way, the temperature inside the luggage compartment 10 is maintained near the set temperature (S3).

On the other hand, the CPU 32 determines the pre-cooling state of the cargo in the luggage compartment 10 detected by the heat detection sensor 30, that is, the temperature difference between the inside temperature corresponding to the output of the sensor 30 and the temperature of the inside cargo. The air volume is calculated based on ΔT ₂ . The calculation of the air volume is performed based on the air volume data stored in the storage unit 33. The air volume data stored in the storage unit 33 corresponds to the graph as shown in FIG. 6, and is for calculating the air volume based on the temperature deviation ΔT ₂ . As is clear from this figure, when the load is pre-cooled sufficiently and the difference between the temperature of the load and the temperature inside the refrigerator is 2 ° C or less, the evaporator fan 13 operates at the set minimum speed. Driven. If the difference is 5 ° C or more, the evaporator fan 13 is driven at the set maximum speed. When the temperature deviation ΔT ₂ is 2 ° C. or more and less than 5 ° C., the rotation speed of the fan 13 is increased / decreased in proportion to the value of the temperature deviation. The reason for controlling in this way is to save the power consumption of the compressor 17, the evaporator fan 13, etc. because the cargo can be sufficiently cooled without increasing the air volume when the luggage is sufficiently precooled. Moreover, in such a case, rather small air volume can reduce the amount of external heat intrusion, so that efficient cooling can be performed. On the other hand, if the load is not pre-cooled and the temperature difference from the internal temperature is large, it is necessary to cool the load quickly, so that the air volume is increased and the refrigerator capacity is increased to lower the temperature of the load rapidly. Yes (S4). In order to realize the optimum air volume calculated in this way, the CPU 32 calculates the voltage to be applied to the evaporator fan 13 and applies the voltage to the air blower controller 35 to the evaporator fan 13. To issue a command (S5). The air flow rate control unit 35 applies a voltage based on this command to the evaporator fan 13 to cool the inside of the refrigerator with a predetermined air flow (S6).

As described above, according to the present embodiment, the air volume in the refrigerator is changed according to the pre-cooling state of the cargo in the luggage compartment 10. Therefore, it is possible to always perform efficient cooling in the refrigerator. Further, it is possible to reduce the driving power of the evaporator fan 13 and the compressor 17. Further, since the evaporator fan 13 is not always driven at the maximum rotation speed, its durability is improved.

[0017]

[Effect of the device]

 As described above, according to the present invention, it becomes possible to always and efficiently cool the load in the refrigerating compartment in accordance with the pre-cooling state, and further reduce the power consumption of the device. become.

[Brief description of drawings]

FIG. 1 is a schematic configuration diagram of a refrigerator for cold storage vehicles according to the present invention.

FIG. 2 is a control block diagram around the control device of the refrigerator for the cold carrier vehicle of FIG.

FIG. 3 is a view showing a mounting position of the heat detection sensor of FIG.

FIG. 4 is an operation flowchart of the control device of FIG.

5 is a diagram for explaining ON / OFF control of a compressor controlled by the control device of FIG. 1. FIG.

FIG. 6 is a diagram for explaining a process of calculating an air volume calculated by the control device of FIG. 1.

FIG. 7 is a schematic configuration diagram of a conventional general cold storage vehicle.

FIG. 8 is a schematic configuration diagram of a cooling system and a control system of the refrigerator of the cold storage vehicle of FIG.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 10 ... Luggage compartment (refrigerator) 12 ... Evaporator 13 ... Evaporator fan (Blower) 14 ... Suction temperature sensor 17 ... Compressor 19 ... Condenser 20 ... Condenser fan 22 ... Flow control element 30 ... Heat detection sensor (precooling state detection means) 32 ... CPU (air flow rate calculation means) 35 ... Air flow rate control unit (air flow rate calculation means)

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Tsunemi Ikeda 5-24-15 Minamidai, Nakano-ku, Tokyo Calsonitz Co., Ltd. (72) Shunichi Yamanaka 5-24-15 Minamidai, Nakano-ku, Tokyo Calsonitz Co., Ltd. (72) Creator Yasuhisa Nakahara 5-24-15 Minamidai, Nakano-ku, Tokyo Calsonitz Co., Ltd.

Claims (1)

[Claims for utility model registration] [Claim 1] An evaporator (12) for cooling the air in the refrigerator compartment (10), and circulating the air in the refrigerator compartment (10) through the evaporator (12) A blower (13), a pre-cooling state detecting means (30) for detecting a pre-cooling state of the cargo in the refrigerating room (10), and the refrigerating room detected by the pre-cooling state detecting means (30)
Based on the pre-cooled state of the baggage in (10), the blower amount calculation means (32, for calculating the optimum blown amount by the blower (13) so that the baggage in the refrigerating room (10) can be efficiently cooled. 35) A refrigerating machine for a cold storage vehicle, comprising: