JPH09109664A - On-vehicle refrigerating device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an on-vehicle refrigerating device which is driven by a vehicle engine and utilizes an air refrigerating cycle. SOLUTION: A refrigerating truck is provided with a cooling chamber 30 in which loaded cargoes are kept at a specified low temperature, and the cooling chamber 30 is cooled by an air cycle refrigerating device. Also the outlet of the cooling chamber 30 is connected to a compressor 1 through a regenerator 4, and a heat exchanger 2 is connected to the outlet of a compressor 1. The heat exchanger 2 is connected to an air turbine 3 through the regenerator 4, and the inlet of the cooling chamber 30 is connected to the outlet of the air turbine 3. The compressor 1 is connected to the output shaft of a vehicle engine 5 through a step-up gear 6, a CVT 7, and a clutch 8, and the CVT 7 and clutch 8 are controlled based on the temperature of the cooling chamber 30 and the engine rotational speed so as to control the speed of the compressor 1.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a vehicle-mounted refrigeration system utilizing an air refrigeration cycle driven by a vehicle engine.

[0002]

2. Description of the Related Art Refrigerating apparatuses using a vapor compression refrigeration cycle using fluorochloro-substituted hydrocarbons as refrigerants have a large coefficient of performance and have been used in various refrigerators. However, recently, adverse effects on the ozone layer and the greenhouse effect have been discovered.

Further, there are the following refrigerating apparatuses. 1. It uses the latent heat of vaporization of liquid nitrogen. In the United States, refrigeration vehicles are used that utilize the latent heat of vaporization of liquid nitrogen produced as a by-product of liquid oxygen. But,
The disadvantage is the limited supply of liquid nitrogen. 2. It uses a Peltier element. It has been applied to refrigerant with a very small capacity, such as frozen transportation of human tissue. However, since the coefficient of performance is low, the coefficient of performance is limited to several tens of watts. 3. Livestock cooling type It uses the latent heat when the ice melts, and it is low cost. As with, there is a problem with the sustainability of the cold storage effect. 4. It uses an air refrigeration cycle. It compresses air, cools high-temperature and high-pressure air with a heat exchanger, and then expands it to near atmospheric pressure with an expander to obtain cold air. It is used for cooling, refrigerating and refrigerating aircraft.

The air refrigeration cycle has the following features as compared with the vapor compression refrigeration cycle.・ Because it is an open cycle, cold air can be obtained at the same time as the operation starts. -Since no refrigerant such as fluorochloro-substituted hydrocarbons is used, it is not necessary to consider high-pressure gas leakage. -The structure of the refrigeration system is simpler and less expensive than the vapor compression refrigeration cycle that requires a compressor, a condenser, an expansion valve, and an evaporator. -There is a possibility that the temperature distribution inside the freezer can be made uniform by increasing the air volume.・ The coefficient of performance is small.

[0005]

Conventionally, a refrigerating truck has been equipped with a refrigerating apparatus utilizing a vapor compression refrigerating cycle, and has the above-mentioned problems.

An object of the present invention is to provide a vehicle-mounted refrigeration system utilizing an air refrigeration cycle driven by a vehicle engine.

[0007]

The present invention is an air compressor,
A refrigeration system using an air refrigeration cycle that is equipped with a heat exchanger that cools compressed air and an expander that expands the cooled compressed air, and that is driven by a vehicle engine.
A transmission and a clutch are provided between the air compressor and the vehicle engine.

The transmission and the clutch may be controlled based on the temperature of the cooling chamber of the cargo provided in the vehicle and the engine speed.

As a result of the above, it is possible to give the air compressor a required number of revolutions with respect to the cooling load regardless of the variation in the number of revolutions of the vehicle engine. For example, even when the cooling load is large and the rotation speed of the vehicle engine is low, or when the cooling load is small and the rotation speed of the vehicle engine is high, the transmission apparatus is based on the temperature of the vehicle cooling chamber and the engine rotation speed. Is controlled so that an optimum rotation speed can be given to the air compressor. Also, when the cooling load is extremely small, the operation of the refrigeration system is stopped by disengaging the clutch.

An air compressor may be coaxially connected to the expander. Since the rotational force recovered by the expander can be transmitted to the compressor side, the driving power of the compressor can be reduced.

Further, it is preferable to provide a regenerator for cooling the air flowing into the expander by utilizing the return air from the cooling chamber of the vehicle. Because the air flowing into the expander is cooled more,
The coefficient of performance can be improved.

[0012]

BEST MODE FOR CARRYING OUT THE INVENTION

(Embodiment 1) An embodiment of the present invention will be described with reference to FIG. The freezing truck is equipped with a cooling chamber 30 for holding cargo such as vegetables, fruits, or ice cream at a predetermined low temperature. The cooling chamber 30 is maintained at a predetermined low temperature by a refrigerating device using an air refrigeration cycle. It is supposed to be done.

A refrigerating apparatus using an air refrigerating cycle (hereinafter, also referred to as an air cycle refrigerating apparatus) will be described below.

The air cycle refrigerating apparatus has an air compressor 1, an air cooling heat exchanger 2, an air turbine 3 as an expander, and a regenerator 4. The air outlet of the cooling chamber 30 is connected to the inlet of the air compressor 1 via the regenerator 4, and the compressor 1 sucks the air in the cooling chamber 30 and turns it into high temperature and high pressure air. A turbo radial type compressor is used as the compressor 1. An air-cooled heat exchanger 2 is connected to the outlet side of the compressor 1 and is cooled by heat exchange with the outside air while the high temperature and high pressure air in the compressor 1 passes through the heat exchanger 2. It Since the cooling by the heat exchanger 2 is the cooling by the outside air, the temperature of the cooled air is limited to the outside air temperature.

The regenerator 4 is provided to further cool the high pressure air cooled by the heat exchanger 2. The regenerator 4 is a heat exchanger that cools using the return air in the cooling chamber 30, and the high-pressure air flowing from the air-cooling heat exchanger 2 into the air turbine 3 through the inside of the regenerator 4 is cooled by the cooling chamber 30. Is cooled by heat exchange with relatively low temperature return air flowing into the compressor 1 through the air outlet of the regenerator 4.

The high-pressure air cooled by the air-cooling heat exchanger 2 and the regenerator 4 flows into the air turbine 3 connected to the outlet of the regenerator 4 and expands to become low-temperature, low-pressure air. Cooling chamber 3 connected to the outlet of air turbine 3
It is returned to the cooling chamber 30 from the 0 air inlet. As the air turbine 3, a turbo radial type is used.

Next, the drive device of the air compressor 1 will be described. An air compressor 1 is coaxially connected to an air turbine 3, and an input shaft of the air compressor 1 is a CVT via a speed increaser 6.
(CONTINOUUSLY VARIABLE TR
(ANSMISSION) 7 is connected. CVT7
Is connected to the output shaft of the vehicle engine 5 via the clutch 8. The temperature detecting means 9 of the cooling chamber 30 and the engine speed detecting means 10 are provided, and the CVT 7 is provided.
The control unit 11 controls the pulley ratio in accordance with the detected temperature of the cooling chamber 30 and the engine speed, so that the compressor 1 is provided with a required speed. For example, the cooling load is large,
Even when the rotation speed of the vehicle engine 5 is low, or when the cooling load is small and the rotation speed of the vehicle engine 5 is high, the compressor 1 uses the CVT 7 based on the temperature in the cooling chamber 30 and the engine rotation speed. Gives the optimum number of rotations. Similarly, by the control means 11,
When the cooling load is extremely small, the operation of the refrigeration system is stopped by disengaging the clutch 8.

Since the air compressor 1 and the air turbine 3 are coaxially connected, the rotational force of the air turbine 3 is applied to the compressor 1.
Since it can be transmitted to the side, the power for driving the compressor 1 can be saved.

The air compressor 1 is also configured to be driven by a land power motor 13 connected to the CVT 7 via a clutch 12.

According to the above-described embodiment, it is possible to provide a refrigerating apparatus, such as a refrigerating truck, which does not use a refrigerant of fluorochloro-substituted hydrocarbons. Regardless of the fluctuation of the engine speed, the refrigeration system
You can always drive in optimal conditions.

(Second Embodiment) FIG. 2 shows another embodiment of the present invention. The difference of the present embodiment from the above-described embodiment is that in the drive device of the air compressor 1,
Instead of the CVT, a variable hydraulic pump and a hydraulic motor are provided.

That is, the hydraulic motor 14 and the variable hydraulic pump 15 are connected between the speed increaser 6 and the clutch 8. The variable hydraulic pump 15 can change the pressure and the flow rate, and the working oil circulates between the variable hydraulic pump 15 and the hydraulic motor 14. And the cooling chamber 3
The pressure and flow rate of the hydraulic pump 15 are controlled by the control means 16 according to the temperature of the cooling chamber 30 and the engine speed detected by the temperature detection means 9 of 0 and the engine speed detection means 10, thereby controlling the hydraulic pressure. Motor 1
4 is provided with a required number of rotations, and is configured to give the compressor 1 an optimal number of rotations. Similarly, the control means 16 is configured to stop the operation of the refrigeration system by disengaging the clutch 8 when the cooling load is extremely small.

According to the second embodiment described above, in addition to the conditions described in the first embodiment, the installation location of the refrigeration system is not limited to the engine room, and the degree of freedom of the arrangement position is large.

The transmission is not limited to the CVT or the combination of the hydraulic motor and the variable hydraulic pump, but other gears such as a planetary gear can be used. When a two-speed transmission mechanism using a planetary gear device is used, the high speed change ratio and the low speed change ratio may be switched according to the cooling load and the engine speed, or the high speed change ratio and the low speed change ratio may be changed for a certain period of time. You may comprise so that it may switch by a ratio by turns.

[0025]

As described above, according to the present invention, it is possible to provide a vehicle-mounted refrigeration system that uses an air refrigeration cycle driven by a vehicle engine.

[Brief description of the drawings]

FIG. 1 is a configuration explanatory view showing an embodiment of the present invention.

FIG. 2 is a structural explanatory view showing another embodiment of the present invention.

[Explanation of symbols]

 1 Air Compressor 2 Air Cooling Heat Exchanger 3 Air Turbine 4 Regenerator 5 Vehicle Engine 6 Speed Booster 7 CVT 8 Clutch 9 Cooling Chamber Temperature Detecting Means 10 Engine Speed Detecting Means 11 Control Means 12 Clutch 13 Land Power Motor 14 Hydraulic motor 15 Variable hydraulic pump 16 Control means 30 Cooling chamber

Continuation of the front page (72) Inventor Kyosuke Sasaki 15-1 Fukucho-cho, Shinjuku-ku, Tokyo Hishiju Cold Chain Co., Ltd.

Claims (4)

[Claims] 1. A refrigeration system using an air refrigeration cycle driven by a vehicle engine, comprising an air compressor, a heat exchanger for cooling the compressed air, and an expander for expanding the cooled compressed air. A vehicle-mounted refrigeration system, wherein a transmission and a clutch are provided between the air compressor and the vehicle engine. 2. The in-vehicle refrigeration system according to claim 1, wherein the transmission and the clutch are controlled based on a temperature of a cargo cooling chamber provided in the vehicle and an engine speed. 3. The on-vehicle refrigeration system according to claim 1, wherein an air compressor is coaxially connected to the expander. 4. The vehicle-mounted refrigeration system according to claim 1, further comprising a regenerator that cools the air flowing into the expander by using the return air from the cooling chamber of the vehicle. .