JPH0712444A - Vehicle with gas engine equipped with refrigeration system - Google Patents

Abstract

(57) [Abstract] [Purpose] To provide a vehicle equipped with a gas engine equipped with a freezer that can stably maintain a cooling state even when the engine is stopped. [Configuration] Fuel gas supply path (1) from a fuel tank (6) having a heat insulating structure for storing low temperature liquefied gas to a gas engine (1)
Place the regenerator (8) in 2). The refrigerant liquid (9) stored inside the regenerator (8) and the low temperature liquefied gas passing through the regenerator (8) are heat-exchanged with each other to heat the vaporization of the low temperature liquefied gas to cause the refrigerant liquid (9).
Have a large amount of cold energy. Cooling energy held by the refrigerant liquid (9) is discharged from the radiator (4) arranged inside the freezer (2) into the freezer (2) to cool the inside of the freezer (2). The refrigerant liquid (9) is circulated between the regenerator (8) and the radiator (8).

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a vehicle equipped with a gas engine that uses a low temperature liquefied gas such as liquid hydrogen, liquefied natural gas, liquefied petroleum gas, etc. as a fuel, and more particularly to a gas engine refrigerating vehicle equipped with a freezer.

[0002]

2. Description of the Related Art A gas engine of this kind, for example, a hydrogen gas engine, has a characteristic that exhaust gas is clean and high output is obtained because it does not discharge a gas harmful to human body such as carbon monoxide or hydrocarbon during hydrogen combustion. In this hydrogen gas engine, liquid hydrogen in a fuel tank is vaporized into high-pressure hydrogen gas by a heat exchanger, and then this hydrogen gas is injected into a cylinder of the engine for combustion. Until now, air has been used as a medium for vaporizing liquid hydrogen into hydrogen gas in a heat exchanger, and the air that has become low temperature during vaporization is warmed by the atmosphere surrounding the heat exchanger and repeatedly used for vaporizing liquid hydrogen. It was

On the other hand, in a refrigerating vehicle or a vehicle with a car cooler that has been generally used in the past, by rotating a compressor attached to an engine, a gas as a refrigerant is compressed into a high temperature and high pressure gas, which is then condensed by a condenser. After making the liquid at room temperature and high pressure, this refrigerant is rapidly expanded to a low temperature and low pressure liquid, which is vaporized by an evaporator to remove heat from the surrounding air, thereby cooling the freezer and the passenger compartment.
Therefore, in a conventional vehicle with a freezer or a car cooler, the engine load for driving the compressor is large, and the vehicle weight increases due to the condenser and the evaporator, and
There was a problem that a large installation space was also required.

Therefore, the present applicants have previously proposed a vehicle for cooling a freezer or a passenger compartment by utilizing the heat of vaporization of liquefied gas.
(JP-A-5-104945). In this system, a heat exchanger that vaporizes the liquefied gas discharged from the liquefied gas tank is placed in the freezer or in the passenger compartment or in the intake system of the engine, and the air that has become cold when the liquefied gas is vaporized is supplied to the freezer or the passenger compartment. To cool the space or cool the intake air for engine combustion.

[0005]

However, in the vehicle with a cooling device proposed above, low temperature air that has exchanged heat with the liquefied gas used as the fuel of the engine in the heat exchanger is directly used as the cooling medium. Therefore, while the engine is stopped, the supply of fuel gas is stopped and the cooling itself is also stopped. Therefore, in the case of a refrigerating vehicle equipped with a freezer, the temperature inside the freezer may rise when the engine is stopped for a long time, and the rotation of the engine must be maintained to cool the inside of the freezer. Therefore, it was found that the fuel wasted in vain.

In addition, since heat is directly exchanged between the liquefied gas used as fuel for the engine in the heat exchanger and the air in the freezer, when flammable fuel leaks into the freezer,
It was predicted that there would be a risk of ignition and explosion in the freezer, and it was revealed that there was a safety problem. An object of the present invention is to provide a vehicle equipped with a gas engine, which is capable of stably maintaining a cooling state even when the engine is stopped and is equipped with a safe freezer.

[0007]

In order to achieve the above object, the present invention has a regenerator arranged in a fuel gas supply path from a fuel tank to a gas engine, and the refrigerant liquid and the regenerator stored inside the regenerator. Cooling energy is stored in the refrigerant liquid by exchanging heat with the low-temperature liquefied gas passing through the refrigerator, and the refrigerant liquid storing this cooling energy is circulated to the radiator arranged inside the refrigerator to cool the inside of the refrigerator. It is characterized by being configured in.

[0008]

In the present invention, the regenerator is arranged in the fuel gas supply path from the fuel tank to the gas engine, and the heat exchange is performed between the refrigerant liquid stored in the regenerator and the low temperature liquefied gas passing through the regenerator. However, since the refrigerant liquid in the regenerator is circulated through the radiator arranged inside the freezer to cool the inside of the freezer, even if the gas supply to the engine is stopped, it is stored in the regenerator. The cold energy of the refrigerant liquid thus obtained acts as a cold heat source for cooling the inside of the freezer. As a result, it is not necessary to operate the engine to maintain the temperature in the freezer, which contributes to fuel saving. Moreover, since the combustible gas for fuel does not enter the freezer, the fuel gas does not leak into the freezer.

[0009]

FIG. 1 is a schematic configuration diagram of a liquefied gas supply system in a refrigeration vehicle to which the present invention is applied. This refrigeration vehicle is equipped with a hydrogen gas engine (1) as a drive engine and
A freezer (2) is mounted on the loading platform, and this freezer is
Inside the (2), a refrigeration system (5) composed of a fan (3) and a radiator (4) is arranged.

The hydrogen gas supplied to the hydrogen gas engine (1) is stored in the fuel tank (6) as liquid hydrogen. And the liquid hydrogen pump (7) for pumping liquid hydrogen from the fuel tank (6)
The liquid hydrogen pumped out at is guided to the regenerator (8), is heat-exchanged with the refrigerant liquid (9) in the regenerator (8) and is vaporized, and the vaporized high-pressure hydrogen gas is surge tank (10). Engine through
It is guided to the gas injector (11) attached to (1). In the fuel gas supply path (12) between the fuel tank (6) and the engine (1), at least the fuel tank (6) is connected to the regenerator.
Super-insulated pipes are used up to (8).

The fuel tank (6) is composed of a stainless steel double-structured tank body (13) and an outer case (14) covering the tank body (13). A vacuum is created between the walls to form a heat insulating layer (15). Further, a pipe (16) having a high thermal conductivity is wound around the outer wall surface of the tank body (13), and the gas component in the tank body (13) is circulated in the pipe (16) to allow the tank body (13) to flow. The heat input into the tank body (13) is suppressed by cooling the outer wall of (). A three-way valve (18) is arranged in the discharge path (17) for hydrogen gas flowing through the pipe (16), and one gas outlet pipe (19) led out from the three-way valve (18) is connected to the engine (1 ) Intake port (20)
The other gas outlet pipe (21) communicates with the stack (23) via the catalytic combustor (22).

The regenerator (8) is internally provided with a refrigerant liquid (9)
A 0% calcium chloride aqueous solution is stored, a liquid hydrogen conducting tube (24) is arranged in a coil shape, and the outer surface of the regenerator body is heat-insulated and coated with 100 mm urethane foam. The regenerator (8) is connected to the refrigerating device (5) in the freezer (2) by the refrigerant liquid delivery passage (25) and the refrigerant liquid return passage (26), and is connected to the refrigerant liquid delivery passage (25). Electric refrigerant liquid delivery pump (2
7) is arranged so that the refrigerant liquid in the regenerator (8) is circulated between the regenerator (8) and the refrigerating device (5). That is, the refrigerant liquid (9) in the regenerator (8) is transferred to the refrigerant liquid delivery pump (27).
Is supplied to the radiator (4) of the refrigeration system (5).
The refrigerant liquid after heat exchange with the air flow in the freezer generated by the fan (3) in (4) and heat dissipation in the freezer (2) is a regenerator.
It is designed to return to (8). And the refrigerant liquid delivery path
(25) is heat-insulated with urethane foam to enhance the cooling effect in the freezer (2).

If the refrigerant liquid (9) in the regenerator (8) becomes too cold, the fluidity will decrease and the refrigeration system (5) in the freezer (2) will
The refrigerant liquid (9) cannot be sent smoothly to the regenerator.
The inlet part and the outlet part of (8) are connected by a bypass passage (30) in which a flow path on-off valve (28) and a heat exchanger (29) are arranged, and a bypass at the inlet part of the regenerator (8). The inlet valve (31) is arranged closer to the regenerator (8) than the branch point. The flow passage opening / closing valve (28) and the inlet valve (31) are configured to be switched and controlled by the temperature of the refrigerant liquid or the temperature of hydrogen gas flowing out from the regenerator (8). That is, when the temperature of the refrigerant liquid (9) becomes lower than a predetermined temperature or the temperature of the hydrogen gas flowing out from the regenerator (8) becomes lower than the predetermined temperature, the flow passage opening / closing valve (28) of the bypass passage (30). Valve is closed, the inlet valve (31) of the regenerator (8) is closed, and liquefied hydrogen in the fuel tank (6) is caused to flow into the bypass passage (30). It is exchanged and vaporized, and the vaporized gas is sent to the surge tank (10). Further, when the temperature of the refrigerant liquid (9) is higher than a predetermined temperature, or when the temperature of the hydrogen gas flowing out from the regenerator (8) is higher than the predetermined temperature, the flow path opening / closing valve of the bypass passage (30) ( 28) closed and the inlet valve (31) of the regenerator (8)
Liquefied hydrogen in the fuel tank (6) is sent to the surge tank (10) via the regenerator (8).

In the figure, reference numeral (32) is a liquid hydrogen supply port to the fuel tank (6), (33) is a liquid level indicator for displaying the liquid amount in the fuel tank (6), and (34) is the fuel tank (6). ) Pressure gauge,
(35) is a gas vent passage from the inside of the fuel tank (6). The degassing passage (35) communicates with the stack (23). Also,
Reference numeral (36) is a temperature sensor arranged inside the ceiling wall of the freezer (2), (37) is a fan pump driver for controlling the fan (3) and the refrigerant liquid delivery pump (27), and (38) is a fan pump. Fan control lead wire derived from the driver (37), (3
9) is a lead wire for controlling the refrigerant liquid delivery pump derived from the fan pump driver (37), (40) is an injection pump that controls the opening and closing of the fuel injector (11), and (41) is the fuel injector (11). A working fluid storage container.

In the refrigerating vehicle having such a structure, the liquid hydrogen supplied to the engine (1) is passed through the regenerator (8) which stores the refrigerant liquid (9), whereby the liquid hydrogen and the refrigerant liquid (9) are separated from each other. Cooling energy is stored in the regenerator (8) by heat exchange, and the refrigerant liquid (9) cooled by the heat of vaporization of liquid hydrogen is supplied to the refrigerating device (5) in the freezer (2) to supply the refrigerant liquid ( Since the cold energy held in 9) is released into the freezer (2) to keep the inside of the freezer (2) at a low temperature, even if the extraction of liquid hydrogen is stopped when the engine is stopped, the cold storage is stopped. Since the refrigerant liquid in the container (8) retains a large amount of cold energy, the refrigerant liquid delivery pump (27) is operated by the power of the battery or the like while the engine is stopped, so that the refrigerant liquid (9) is frozen.
It can be circulated to the refrigeration system (5) of (2), and the cooling state can be maintained.

When the temperature sensor (36) inside the freezer detects that the temperature inside the freezer (2) is below a predetermined temperature, the fan / pump driver (37) sends a stop signal via the lead wire (38). Is sent, the fan (3) in the freezer (2) is stopped, and forced convection cooling is changed to natural convection cooling. Nevertheless, if the temperature in the freezer (2) drops below the specified temperature,
A pump stop signal from the lead wire (39) indicates that the refrigerant liquid delivery pump (2
7), and the refrigerant liquid delivery pump (27) stops. When the temperature reaches or exceeds the predetermined temperature, the reverse operation is performed and cooling is started.

In the above embodiment, the refrigerating vehicle equipped with the hydrogen gas engine was explained, but the present invention is also applied to the refrigerating vehicle equipped with the gas engine which uses a low temperature liquefied gas such as liquefied natural gas or liquefied petroleum gas. can do.

[0018]

As described above, according to the present invention, the low temperature liquefied gas to be supplied to the engine is passed through the regenerator storing the refrigerant liquid to exchange heat between the liquid hydrogen and the refrigerant liquid. Because cold energy is stored in the refrigerator and this refrigerant liquid is supplied to the refrigerating device in the freezer to keep the inside of the freezer at a low temperature, the freezer can be cooled even when the engine is stopped, and wasteful consumption of fuel is prevented. can do.

[Brief description of drawings]

FIG. 1 is a schematic configuration diagram of a liquefied gas supply system in a refrigeration vehicle showing an embodiment of the present invention.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Gas engine, 2 ... Freezer, 4 ... Radiator, 6 ... Fuel tank, 8 ... Regenerator, 9 ... Refrigerant liquid, 12 ... Fuel gas supply passage, 28 ... Flow passage opening / closing valve, 30 ... Bypass passage, 31 ... Inlet valve.

 ─────────────────────────────────────────────────── ─── Continuation of front page (72) Inventor Seiji Hikino 3-1-1 Hinodai, Hino-shi, Tokyo Inside Hino Motor Co., Ltd. (72) Inventor Masao Komatsu 2-7-1 Hatchobori, Chuo-ku, Tokyo Iwatani Industrial Co., Ltd. Tokyo Head Office (72) Inventor Tatsuhiko Hashimoto 2-7-1, Hatchobori, Chuo-ku, Tokyo Iwatani Industrial Co., Ltd. Tokyo Head Office (72) Inventor Yoshito Tsuruta 2-7 Hatchobori, Chuo-ku, Tokyo Iwatani Sangyo Co., Ltd. Tokyo Head Office (72) Inventor Goichi Inoue 1095 Katsube Town, Moriyama City, Shiga Prefecture Iwatani Sangyo Co., Ltd. Shiga Technical Center

Claims (2)

[Claims] 1. A fuel tank (6) having a heat insulating structure for storing low temperature liquefied gas, a gas engine (1) using the vaporized gas of the liquefied gas stored in the fuel tank (6) as a fuel, and a freezer.
In a vehicle equipped with a gas engine equipped with (2), the regenerator (8) is arranged in the fuel gas supply path (12) from the fuel tank (6) to the gas engine (1), and the regenerator (8) The refrigerant liquid (9) stored inside exchanges heat with the low temperature liquefied gas passing through the regenerator (8), and the refrigerant liquid (9) in the regenerator (8) is placed inside the freezer (2). Freezer by circulating it to the radiator (4)
(2) A vehicle equipped with a gas engine equipped with a refrigeration system configured to cool the inside. 2. A flow passage opening / closing valve (28) and an inlet valve to the regenerator (8), wherein the fuel gas inlet / outlet of the regenerator (8) is short-circuited by a bypass passage (30) and the bypass passage (30) is arranged. A gas engine-equipped vehicle equipped with the refrigeration system according to claim 1, wherein the opening / closing control of (31) is performed based on the temperature of the refrigerant liquid (9).