BG105182A - System and method for air cooling in transport vehicles using liquefied or compressed gas for fuel - Google Patents

Abstract

The system and the method are used in transport vehicles with gas systems for their combustion. They are used for cooling the air, without increasing the fuel consumption and without any impairment of the operation of the engine. By means of pipe connections and switching elements (1, 2, 3 and 4) and smooth adjustment of the discharge (motor valves, servo valves or thermostat valves) an additional circulation circuit is formed for the cooling agent between an additional evaporator (8) and radiator (6) of the heater. In this way normal operation of the engine (5) is ensured in any mode of operation (regardless of the momentary fuel consumption) without any cyclic freezing and defrosting of the evaporator. This is the result of the stable temperature mode of an additional evaporator (8) which is effected for the introduction of a feedback between the temperature in its heating volume and the ratio V1: V2 of mixing cold agent V1 from the additional circulation circuit and the hot agent from the engine (5) by making use of standard thermostatic valves (1 and 2). Their sensors are mounted in the additional circulation circuit and they continuously add hot agent of the required amount to ensure constant temperature. 3 claims, 2 figures

Description

Air cooling system and method for vehicles using liquefied or compressed gas

Technical field

The invention relates to the field of automotive gas systems and to the field of air conditioners. And there are also applications for cooling air in trucks, agricultural machinery and other vehicles that use liquefied or compressed gas.

©

BACKGROUND OF THE INVENTION

It is known that the air conditioning of vehicles requires warming in winter and cooling in summer. Warming is most often achieved through so-called. "Steam" - a radiator in which the engine coolant circulates, which is blown out of the cabin air and warms it up. The cooling is achieved by installing an entire refrigeration system - compressor, condenser element and evaporator element.

This system has the following disadvantages:

- high price - over $ 1000, which is why it is not fitted to all vehicles;

- energy intensity - increases fuel consumption by 1-1.5 liters per 100 km;

- takes away from the power of the engine, as a result of which, when the air conditioner is switched on, the vehicle's dynamic performance deteriorates.

The following patent solutions are also known:

IN USA:

2183452 Dec. 1939 Gibbs et al. 62/7.

2224740 Dec., 1940 Melcher 62/7.

2227927 Jan., 1941 Downs 62/7.

2753856 Jul., 1956 Rush 62/7.

3021681 Feb., 1962 Perry 62/238.

5314007 May., 1994 Christenson 165/43

5560212 Oct., 1996 Hansen 62/7

U.S. Pat. No. 5,560,212 describes an air cooler in vehicles using liquefied gas fuel, which includes a standard evaporator reducer mounted between the liquefied gas tank and the engine, valves and a reservoir for coolant accumulation in the auxiliary circulation circuit. A defrost cycle controlled by sensors and valves is introduced here.

Known priorities are described in the patent cited above. None of them include the system and method set out below.

SUMMARY OF THE INVENTION

One of the object of the invention is to make the cooling of the air in vehicles using liquefied gas fuel so cheap that the system will be fitted to all vehicles with gas appliances without significantly affecting their price.

Another object of the invention is the stable operation of the engine in all modes and simplicity of construction.

Another object of the invention is not to increase fuel consumption when operating the system.

Another object of the invention is not to impair the dynamic performance of the vehicle.

It is an additional object of the invention to make it possible to start a cold gas engine (without switching gasoline while the engine is warming up).

According to the invention, these objectives are achieved by the inclusion of an additional one-stage evaporator between the liquefied gas tank and the evaporator gearbox of the automobile gas device. Its heated volume is included in the additional circulation circuit with the radiator of the heater in the cabin. The fluid circulating in this circuit carries the heat needed for the phase transition or for the expansion of the compressed gas. This one-stage evaporator is a special construction providing heat exchange between the liquid gas and the liquid in the auxiliary circulation circuit, despite its significantly lower temperature. In order to "cool" the air in the cabin, the fluid in the auxiliary circulation circuit must be at a temperature of 12 - 20 ° C - significantly lower than 80 - 90 ° C - as much as the operating temperature of the coolant in the engine for which the gearbox is designed. evaporators of automotive gas appliances. According to the formula for the transfer of heat - Q between two media with a difference in temperature - ΔΤ, through a barrier with thickness - d, area S and a coefficient of thermal conductivity λ - (Q = S.AT.X / d). Therefore, ΔΤ is reduced by 5-6 times and in order to ensure the transfer of sufficient amount of heat to evaporate the liquid gas required for normal engine power in all operating modes, the area S of heat exchange (by ribbing) and the coefficient λ must be increased by use of materials with higher thermal conductivity - aluminum or copper.

Included servo-valves, motor-valves or thermostatic valves, which constantly monitor the temperature in the one-stage evaporator and mix (as in a battery) cold coolant - VI from the new circuit and hot coolant -V2 from the engine, depending on the required amount of evaporated gas (according to the instantaneous fuel consumption of the engine). They maintain a constant feedback that results in the auxiliary evaporator operating in isothermal mode - at the temperature for which it was designed - without freezing and thawing cycle as in US Pat. No. 5560212 Oct., 1996 Hansen 62/7.

The system removes heat (cools) from the air in vehicles using LPG and uses it to heat a single-stage evaporator. Uses "hidden evaporation heat" (thermodynamic value - the amount of heat that must be brought into 1 kg of liquid heated to boiling temperature to convert to the same temperature as the phase transition energy) to cool the compartment . In the case of compressed gas, the one-stage evaporator (in this case the expander) is again cooled by the expansion of the gas (according to the equation of state - Clapeyron-Mendeleev's Law).

For the transfer of heat from the air into the compartment to a one-stage evaporator, a coolant is used, which circulates in the engine cooling system, in the evaporator reducer and in the radiator of the heater (steam). For this purpose, an additional circulation circuit is created only between the one-stage evaporator and the radiator of the heater. In another embodiment of the invention, the role of a single-stage evaporator 8 can be performed by a specially designed high-pressure reduction stage for a modified two- or three-stage reducer evaporator. Then the additional circulation circuit is formed between the heating volume of the reduction stage for the high pressure of the reducer evaporator and the radiator of the heater. Therefore, the heating volume of the reducer evaporator is divided into two separate volumes - a heated volume for a reduction stage of high pressure and a heated volume for a reduction stage of low pressure. In practice, this means that the two reduction stages are separated from each other in separate housings so that there is no heat exchange between them. This new circulation circuit is formed by two solenoid valves, thermostatic valves or motor valves operated by a thermostat according to the temperature in the heating volume of a high-pressure reduction stage. One of the valves is mounted on a pipeline for supplying fluid from the engine to the pre-heating volume of the reduction stage for the high pressure of the reducer evaporator and the radiator of the heater. The other is mounted on the conduit for removal of the fluid from the preheating volume of the reduction stage for the high pressure of the reducer evaporator and the radiator of the heater to the engine cooling system.

The technical effect is a result of the advantages of the invented system and method over existing models:

- ensures the engine is stable in all modes, providing constant feedback between the instantaneous fuel consumption (ie the amount of heat required to evaporate it, ie the temperature in the heating volume of an additional evaporator or the heating volume of a reduction stage for high pressure) and the mixing ratio of cold liquid - VI of the supplementary circuit and hot fluid - V2 of the engine cooling system, thus guaranteeing the evaporator operation at a predetermined constant temperature - exactly for which it was designed.

- as a result of the special design of the one-stage evaporator, it operates at a temperature of the heating fluid 12-20 ° C and it actually cools the air in the cabin,

- Economy - Utilizes the "evaporation energy" lost in existing models to cool the engine;

- does not take away from the engine power and does not impair the dynamic performance of the vehicle;

- makes it possible to start a cold gas engine as it does not allow the evaporator to freeze - it only takes 5 seconds before the engine starts to switch on;

- high reliability and maintainability (due to simplicity of construction);

- accessibility for mass use due to its low cost (when replacing the motor valve with thermostatic valves;

- the possibility of installing vehicles with standard automotive gas systems already in service.

These and other advantages of the invention are explained by the detailed description in connection with the attached figures.

Description of the figures

Figure 1 is a first embodiment of an air cooling system for vehicles using liquefied or compressed gas for fuel.

Figure 2 is a second embodiment of an air cooling system for vehicles using liquefied or compressed gas.

Examples of carrying out the invention

Example # 1

As shown in Figure 1, one embodiment of the invention includes an electromagnetic servo valve 1 operated by a thermostat according to the temperature in the heating volume 19 of a high-pressure reduction stage 13 mounted on a pipeline for supplying coolant from the engine 5 through pipeline 16 to the heating volume 19 of the high-pressure reduction stage 13 of the liquefied gas evaporator 7 and the radiator of the heater 6. For this purpose, the heating volume of the reducing evaporator 7 is divided by a thermal barrier 11 into two of Components - heated volume 19 of the high-pressure reduction stage 13 and heated volume 20 of the low-pressure reduction stage 14. In practice, this means that the two reduction stages are separated into separate housings and the high-pressure reduction stage 13 is designed for operation at a lower temperature of the warming liquid. And an electromagnetic servo valve 2 operated by a thermostat according to the temperature in the heating volume 19 of the high-pressure reduction stage 13 mounted on the pipeline to drain the coolant through the pipeline 18 from the heating volume 19 to the high-pressure reduction stage 13 of the gearbox- the liquefied gas evaporator 7 and the heater radiator 6 to the engine cooling system 5. The coolant enters the conduit 15 in the heating volume 20 of the reducing stage for low pressure 14 and is discharged via conduit 17 to the heater 5, thereby heating the already evaporated gas to the desired temperature and supplying it to a high-speed gas distributor (SRG) 12. The control is carried out with an electromechanical switch or an electronic control unit connected to the temperature regulator in the heating volume 19 of the high-pressure reduction stage 13 which do not form part of the invention and are not shown.

In the "off" position, the solenoid valves 1 and 2 are open and the heated coolant from the engine 5 heats the two reduction stages of the reducer 7.

When set to on, solenoid valves 1 and 2 reduce the flow of fluid from and to the motor 5, according to the heat consumption (with the possibility of interrupting this flow), the electric pump 9 being switched on and providing coolant circulation only through the radiator 6 of the heater and the heating volume 19 of the high-pressure reduction stage 13. The liquefied gas enters the tank 10 in the high-pressure reducing stage 13, there evaporating and cooling the coolant, which then goes to the radiator of the heater. 6 and cools it and through it the air in the compartment. As a result, cooled air enters the vehicle when the system is switched on and the vehicle is heated. Considering the lower coolant temperature in the radiator 6 of the heater (than the coolant temperature in the engine block 5), in order to avoid icing (to ensure that the amount of heat required for evaporation is transferred), a preheating volume 19 is required. the high-pressure reduction stage 13 be ribbed, the electric pump 9 to provide rapid circulation of the coolant and the servo valves 1 and 2 to pass a little warm coolant from the engine 5 as the thermostat through them maintains in the Greve volume 19 to a reduction degree of a high pressure 13 constant, predetermined temperature of 12-L of 20 ° C

Example 2

As shown in Figure 2, this embodiment of the invention includes an electromagnetic servo valve 1 mounted on the coolant supply line from the engine 5 and the evaporator reducer 7 to the radiator 6 of the heater. Solenoid valve 2 mounted on the conduit to drain the coolant from the radiator 6 of the heater to the reducer 7 and the cooling system of the engine 5. To the two conduits parallel to the radiator 6 of the heater and after the solenoid valves 1 and 2 (solenoid valves 1 and 2 ( seen from the engine 5) a group of one-stage evaporator 8 and an electric pump 9 connected in series are mounted thereto. It provides the fluid circulation in the additional circulation circuit "heater radiator 6 - one-stage evaporator. Arit 8 "when the electromagnetic servo-valves 1 and 2 are actuated by the thermostat.

Branches to the additional one-stage evaporator 8 are mounted on the pipeline from the reservoir 10 to the evaporator reducer 7. The solenoid valves 3 and 4 are mounted so that they either pass the liquid gas through the evaporator 8 and then through the evaporator 7 or it directly enters gearbox evaporator 7 (when system is not on). Control is carried out with an electronic unit in the passenger compartment, which is not part of the invention and is not shown.

With the "off" position, the solenoid servo valves 1, 2 and valve 3 are open and the solenoid valve 4 is closed, the electric pump 9 is not running and the vehicle gas device is operating as intended, the gearbox evaporator 7 supplies evaporated gas to the gearbox gas distributor (GHG) - gas mixer (HS) 12, and from there into the engine 5.

When set to ON, solenoid valves 1 and 2 are actuated by the thermostat, valve 3 is closed and solenoid valve 4 is open. The liquid gas from the reservoir 10 through the solenoid valve 4 enters the additional one-stage evaporator 8 and the evaporator reducer 7 and from there into the engine 5.

As a result, cooled air enters the vehicle when the system is switched on and the vehicle is heated. The servo valves 1 and 2 can be motor valves (stellglied) controlled by the thermostat in the heating volume of a single stage evaporator 8. They can also be replaced by thermostatic valves which by supplying the required amount of hot fluid from the engine 5 maintain a preset temperature in. 0 the heating volume of the evaporator 8, thus protecting it from freezing even with the highest consumption of liquid gas (the busiest mode of the engine).

Application of the invention

The inventive air cooling system in vehicles using liquefied gas fuel can be installed together with the insertion of a "gas device" in the vehicle. And it can also be fitted to vehicles with already installed standard automotive gas systems already in use.

The only condition for it to work is to have liquefied gas from the engine, ie. engine to run. But existing air conditioners and air conditioners have the same requirement.

With the system off, the valves are open to the coolant flow on the existing highway.

At start-up, the valves reduce the flow of fluid from and to the engine so that it forms an additional circulation circuit in which a small electric pump provides rapid circulation of the coolant (since the volume of fluid in this circuit is many times smaller than the total amount of coolant and its the temperature is lower than that of the engine, so that in order to provide the heat exchange it is necessary to finalize the heating volume of a single-stage evaporator (or a high-pressure reduction stage). mode, mix coolant from the secondary circuit and hot fluid from the engine in different ratios V1: V2 to achieve a constant, predetermined optimum temperature for evaporation of the liquid gas in a single-stage evaporator or to a high-pressure reduction stage and thus protect them from freezing irrespective of engine mode - the need for a defrost cycle is eliminated.

One skilled in the art can readily accept many modifications to the preferred embodiment of the invention described in detail above. Therefore, the applicant intends to bind only by the scope of the attached claims.

Attachment: 2 figures

Claims (3)

1. Air cooling system for vehicles using liquefied gas or compressed gas, including: - Heater radiator 6 in the cab - Electric pump 9 included in the auxiliary circulation circuit - engine coolant - pipe connections between the elements, characterized in that it includes: - a specially designed one-stage evaporator 8 connected by tubular connections between the liquefied (compressed) gas tank 10 and the main standard reducer-evaporator 7 of the vehicle gas system, or the heating volume 19 of a high-pressure reduction stage 13 of a specially designed reducer 7 divided reduction stages for high and low pressure into two separate bodies for realization of the heat barrier 11, and - motor-valves, servo-valves or thermostatic valves 1 and 2, with smooth flow control. A system according to claim 1, characterized in that the one-stage evaporator 8 is connected via tubular connections between the liquefied (compressed) gas tank 10 and the main standard reducer-evaporator 7 of the car gas system, or the heating volume 19 of the reducing stage for high pressure 13 of specially designed gearbox evaporator 7 with separate reduction stages for high and low pressure in two separate bodies for realization of thermal barrier 11, are constructed with enlarged area S by ribbing and using materials with -high coefficient of thermal conductivity λ. 3. A method of cooling the air in vehicles using liquefied or compressed gas fuel, characterized in that it supplies the heat required to evaporate the liquefied gas or to expand the compressed gas from the air in the vehicle cab, as in the auxiliary Circulating circuit constantly mix cooled liquid VI from the radiator 6 of the heater and hot fluid V2 from the engine 5 in different proportions by means of motor valves, servo valves or thermostatic valves 1 and 2 with smooth flow control.