JPH0791767A - Air conditioner using absorption refrigerator - Google Patents

Abstract

PURPOSE:To prevent a reverse flow from a dilute solution tank to a refrigerant tank and to store a predetermined quantity of refrigerant by directly coupling the tank to a dilute solution tank via a passage, and equilibrating an internal pressure of the refrigerant tank with a pressure of an evaporator in the step of concentrating solution. CONSTITUTION:A regenerator 12 heats dilute solution in which water is absorbed to absorbent liquid containing lithium bromide solution as a main ingredient and generates refrigerator vapor. An evaporator 10 communicates with a condenser 16 for condensing the vapor through a capillary tube 24, and with a refrigerant tank 18 through a valve V5. On the other hand, a dilute solution tank 21 is connected between the regenerator 12 and an air-cooled type absorber 20. A directional tube 25 having a check valve V4 is connected between the tank 18 and the tank 21. In such a structure, the tank 18 is further directly coupled to the tank 21 via a passage 25, and an internal pressure of the tank 18 is equilibrated with a pressure of the evaporator 10 in the step of concentrating the solution.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an air conditioner using an absorption refrigerating machine for general houses and small buildings.

[0002]

2. Description of the Related Art At present, an air conditioner using an absorption chiller is mainly used for industrial or commercial facilities such as a building or a large store.

In a cooling system of an air conditioner using an absorption refrigerator, a refrigerant vapor evaporated in a regenerator is condensed in a water-cooled condenser, and the condensed refrigerant is guided to an evaporator for evaporation. The cooling heat medium (usually water) that circulates between the fan coil unit provided in the room to be cooled and the refrigerator is cooled by the latent heat of vaporization at that time. On the other hand, the evaporated refrigerant vapor is operated in a cycle in which a water-cooled absorber absorbs the concentrated solution (absorption liquid) and returns it to the regenerator.

In an air conditioner using this type of absorption refrigerator, the temperature of the cold heat medium circulated in the indoor fan coil unit is cooled to around 7 ° C. in the evaporator, and the cold heat medium is circulated in the indoor fan coil. It is circulated to cool the indoor air and return it to the evaporator at around 12 ° C. When using an aqueous lithium bromide solution as the absorbing liquid, it is necessary to maintain the temperature of the absorbing liquid in the absorber at around 40 ° C. To maintain this temperature, a cooling tower is installed on the rooftop or the like, and the water cooling circuit is installed. The method of cooling is adopted.

However, the conventional air conditioner using the absorption type refrigerating machine adopting such a water cooling system has the following problems.

(1) Since the temperature of the absorber is controlled by a water cooling system, the equipment becomes large and piping is required. Therefore, a lot of construction cost is required, which is a problem for general houses and small buildings. Not suitable for cooling.

(2) Since it is necessary to connect the fan coil unit and the refrigerator in the room to be cooled by the pipe for circulating the heating / cooling medium, the construction cost and equipment cost are high. The same applies to an ammonia absorption refrigerator that uses ammonia water as the absorbing liquid and the refrigerant.

Therefore, the present inventors carry out a cooling cycle operation in which the condenser and the absorber are cooled by an air cooling method instead of a water cooling method, and the air to be cooled is directly passed through an evaporator instead of using a cooling / heating medium. A patent application has already been filed for the air conditioner (Japanese Patent Application No. 5-22351).

[0009]

By the way, in this air-cooling type air conditioner, the pipe portion from the condenser to the refrigerant tank is branched into two systems, one of which leads from the condenser to the refrigerant tank and the other of which evaporates from the condenser. It is directly connected to the vessel. A valve is provided in the pipe that directly leads from this condenser to the refrigerant tank. This valve is opened when the solution is concentrated and the solution concentration is increased, such as when the air conditioner is started up, and controls to store the refrigerant in the refrigerant tank. However, when the valve on the opposite side of the refrigerant tank, that is, the valve between the refrigerant tank and the dilute solution tank, is closed, the refrigerant tank approaches a closed state, and the temperature and pressure maintain an equilibrium state. When the temperature of the refrigerant from the condenser rises, the pressure in the refrigerant tank also rises, making it difficult to obtain a pressure difference with the condenser. As a result, there is a problem that the refrigerant is no longer sent out from the condenser to the refrigerant tank, the refrigerant accumulates in the condenser, and finally the liquid level of the regenerator reaches the upper limit and the air conditioner stops.

The present invention has been made in view of the above points. During the solution concentration process, the pressure inside the refrigerant tank is kept in equilibrium with the pressure in the evaporator, and the backflow from the dilute solution tank to the refrigerant tank is prevented. It is an object of the present invention to provide an air conditioner using an absorption refrigerating machine capable of accumulating a predetermined amount of refrigerant in a refrigerant tank regardless of the temperature of the refrigerant.

[0011]

In order to achieve the above object, the present invention generates a refrigerant vapor by heating a dilute solution obtained by absorbing water as a refrigerant in an absorbing solution containing an aqueous solution of lithium bromide as a main component. A regenerator to be made, a condenser that condenses the refrigerant vapor generated in the regenerator by air cooling, is arranged in a duct through which the air to be air-conditioned is circulated, and is connected to the condenser through a pressure loss member such as a capillary. An evaporator, an air-cooled absorber that reacts with an absorbing liquid that absorbs the refrigerant evaporated in the evaporator, a refrigerant tank that is in communication with the condenser via a valve, and the absorber and the regenerator A dilute solution tank connected in between, and a direct connection pipe having a check valve is connected between the refrigerant tank and the dilute solution tank to prevent backflow from the dilute solution tank to the refrigerant tank. Absorption refrigerator In the air conditioning apparatus using, characterized in that a passage directly connected with said dilute solution tank and the refrigerant tank for the pressure inside the refrigerant tank in the concentration process of the solution to equilibrate with the pressure of the evaporator.

[0012]

According to the present invention, since the pressure in the refrigerant tank and the pressure in the dilute solution tank are the same, the pressure in the refrigerant tank is balanced with the pressure in the evaporator during the refrigerant concentration process.
The refrigerant can be sent from the condenser to the refrigerant tank.

[0013]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below with reference to the drawings.

FIG. 1 shows an essential part of an embodiment of an air conditioner using a single-effect absorption refrigerator according to the present invention, and FIG. 2 shows an installed state of the air conditioner according to the present invention.

As shown in FIG. 2, the air conditioner according to the present invention comprises an outdoor unit 1 and an indoor unit 2, and the outdoor unit 1 has the structure as shown in FIG. The indoor unit 2 has only an outlet for cool air and an inlet for indoor air, and is disposed inside the chamber 5. The outdoor unit 1 and the indoor unit 2 are provided with a cool air blowing duct 3 and an indoor air intake duct 4
Connected with. Reference numeral 6 is a remote controller for starting or stopping the operation of the apparatus, setting the room temperature to a desired temperature, and adjusting the amount of cold air blown out.

The inside of the outdoor unit 1 is constructed as shown in FIG. 1, in which an aqueous lithium bromide solution is used as an absorbing liquid and water is used as a refrigerant.

The evaporator 10 is arranged in a portion of the joint between the air duct 3 and the intake duct 4 communicating with the indoor unit 2 in which the room air to be air conditioned flows, evaporates the refrigerant, and passes through it by the latent heat of vaporization. It has a function of cooling air and is communicated with the condenser 16 through a pressure loss member such as a capillary 24. A blower fan 11 is provided in the intake duct 4.

The regenerator 12 has a function of generating refrigerant vapor by absorbing the refrigerant and heating the absorbent having a reduced concentration by the burner 13 and concentrating the concentration of the absorbent. Fuel gas is supplied to the burner 13 from a fuel supply pipe 14, and the degree of combustion is adjusted by a combustion control valve 15.

The condenser 16 has a function of cooling and liquefying the refrigerant vapor sent from the regenerator 12 by the air cooling fan 17, and a part of the refrigerant is stored in the refrigerant tank 18 in order to adjust the concentration of the solution. store. The refrigerant tank 18 is connected to the condenser 16 via a valve V5.

The refrigerant tank 18 and the dilute solution tank 21 are provided in order to prevent backflow from the dilute solution tank 21 to the refrigerant tank 18.
A direct connection pipe 26 equipped with a check valve V4 is connected between and, and the pressures of the refrigerant tank and the dilute solution tank are made equal, and the pressure inside the refrigerant tank 18 is balanced with the pressure of the evaporator 10 in the refrigerant concentration process. A passage portion 25 that directly connects the refrigerant tank 18 and the dilute solution tank 21 is provided so that the refrigerant flows to the refrigerant tank 18.

The absorber 20 stores the absorbing liquid, has a function of absorbing the refrigerant evaporated in the evaporator 10 into the absorbing liquid, and is cooled by the same air cooling fan 17 as the condenser 16. The absorbing liquid whose concentration has been reduced by absorbing the refrigerant is temporarily stored in the dilute solution tank 21.

Reference numeral 22 denotes the regenerator 12 from the dilute solution tank 21.
The heat exchanger 23, which performs heat exchange between the low-temperature absorption liquid having a low concentration toward the absorber and the high-temperature absorption liquid having a high concentration toward the absorber 20 from the regenerator 12, absorbs the refrigerant to reduce the concentration. Replenished liquid from the dilute solution tank 21 to the regenerator 12
The pump 24 for delivering to the evaporator is a pressure loss member such as a capillary provided between the upstream side of the evaporator 10 and the downstream side of the condenser 16.

V1, V2, V3, V4 and V5 are valves, and particularly V4 is a valve having a check function.

The above components are piped as shown.

Next, an electric circuit for controlling the operation of the air conditioner will be described.

T1 is a sensor for detecting the room temperature provided on the upstream side of the evaporator 10, T2 is a sensor for detecting the temperature of the blown air, T3 is a sensor for detecting the liquid level of the regenerator, and T4.
Is a sensor for detecting the condenser temperature.

A controller 30 including a CPU, a memory, and a drive circuit, and a communication controller 31 that receives a setting signal from the remote controller 6 (see FIG. 2) at the receiving section 2a of the indoor unit 2 and receives a signal from the receiving section 2a. Is provided, and the controller 30 receives signals from the sensors T1, T2, T3, and T4,
Upon receiving a signal from the communication controller 31, the blower fan 11,
The operations of the air cooling fan 17, the pump 23, and the fuel control valve 15 of the fuel supply pipe 14 are controlled.

Next, an example of the operation of the cooling cycle will be described with reference to FIG.

Before the start of operation, the valves V1, V3 and V5 are closed and the valve V2 is open. The regenerator 12 is empty.

When the operation button of the remote controller 6 is turned on, the valve V3 is opened (F-1), the motor M2 is driven and the pump 23 sends the absorbing solution from the dilute solution tank 21 to the regenerator 12 (F-2). ). The other valves remain as they are. At this time, the CPU of the controller 30 uses the sensor T4
It is determined whether the liquid level of the regenerator 12 has reached the specified level by observing the signal from (F-3). When the liquid level has reached the specified level, the fuel control valve 15 is opened to supply the fuel gas from the fuel supply pipe 14 to ignite the burner 13 (F-4). Refrigerant vapor is generated in the regenerator 12 and the condenser 16
The temperature of the condenser 16 gradually rises. The CPU of the controller 30 uses the signal from the sensor T4 to determine the condenser 1
It is judged whether the temperature of 6 has reached a predetermined value (F-5),
When the predetermined value is reached, the valves V1 and V5 are opened, the valve V2 is closed (F-6), and the blower fan 11 and the air cooling fan 17 are rotated (F-7). As a result, in the condenser 16, the regenerator 12
The refrigerant vapor sent from is liquefied and flows into the refrigerant tank 18 (air-cooled by the air-cooling fan 17 at this time) when V5 is open, but the capillary 24 when V5 is closed.
Flow into the evaporator 10 and the refrigerant evaporates in the evaporator 10 to remove the latent heat of evaporation, whereby the blower fan 11
Thereby cools the air sent from the room through the intake duct 4. The cooled air is sent to the indoor unit 2 through the air duct 3 and blown into the room 5 as cold air.
Is cooled (F-8).

In this cooling operation, the refrigerant evaporated in the evaporator 10 to become vapor flows into the absorber 20 where it is absorbed by the absorbing liquid. The absorbing liquid, which has absorbed the refrigerant and becomes low in concentration, once enters the dilute solution tank 21 and then the pump 2
3 heat-exchanges with the concentrated high-temperature absorption liquid sent from the regenerator 12 in the heat exchanger 22 through the valve V3,
It is sent to the regenerator 12. This state is the steady mode of operation. During this time, if it is necessary to concentrate the solution, valve V
5 repeats opening and closing.

Here, the temperatures and pressures of the container, the absorbing liquid and the refrigerant in each part of the system during the cooling operation will be exemplified as follows.

Temperature (° C.) Pressure (Torr) Evaporator 10:10 to 20 10 to 20 Regenerator 12: 60 to 90 90 to 110 Condenser 16: 50 to 80 90 to 110 Absorber 20: 45 to 50 11 Refrigerant tank 18: 30-50 50-40 50 Dilute solution tank 21: 40-60 11 Heat exchanger 22: 35-40- Intake duct 4: 26- Blower duct 3: 13-20- Dilute solution: 35-40 Concentration : 61% concentrated solution: 90 concentration: 64.8% When the operation button of the remote controller 6 is turned off (F-9), the blower fan 11 and the air cooling fan 17 are stopped (F-1).
0), meanwhile, the refrigerant in the refrigerant tank 18 and the regenerator 12
Normally, all of the absorbing liquid inside flows into the dilute solution tank 21. This is to prevent the refrigerant tank 18 and the regenerator 12 from being corroded by the absorbing liquid while the apparatus is stopped. The pump 23 stops with a slight delay (F-1
1), the flow of all liquids in the entire system stops.

[0034]

As described above, according to the present invention,
In order to prevent the reverse flow from the dilute solution tank to the refrigerant tank, a direct connection pipe having a check valve is connected between the refrigerant tank and the dilute solution tank, and the pressure inside the refrigerant tank is increased during the concentration process of the solution. In order to equilibrate with the pressure of the evaporator, since the passage portion directly connecting the refrigerant tank and the dilute solution tank is provided, the refrigerant tank while the pressure inside the refrigerant tank is in equilibrium with the pressure of the evaporator during the concentration process of the solution. Since the refrigerant accumulates in the refrigerant, it is possible to accumulate a predetermined amount of refrigerant from the condenser in the refrigerant tank regardless of the temperature of the refrigerant, and to prevent the overflow of the refrigerant tank and prevent crystallization. can get.

[Brief description of drawings]

FIG. 1 is a block diagram of a main part of an embodiment of an air conditioner according to the present invention.

FIG. 2 shows an installed state of an air conditioner according to the present invention.

FIG. 3 shows a flow chart of a steady mode of operation of an air conditioner according to the present invention.

[Explanation of symbols]

 1 Outdoor unit 2 Indoor unit 3 Blower duct 4 Intake duct 5 Room 6 Remote control 10 Evaporator 11 Blower fan 12 Regenerator 13 Burner 16 Condenser 17 Air-cooling fan 18 Refrigerant tank 20 Absorber 21 Dilute solution tank 25 Passage part 26 Direct connection pipe 30 Controller 31 Communication controller T1, T2, T3, T4 Sensor V1, V2, V3, V4, V5 valve

Claims (1)

[Claims] 1. A regenerator for generating a refrigerant vapor by heating a dilute solution in which water as a refrigerant is absorbed in an absorption liquid containing an aqueous lithium bromide solution as a main component, and a refrigerant vapor generated in the regenerator by air cooling. A condenser that condenses, an evaporator that is arranged in a duct through which air to be conditioned in the room flows, and that is in communication with the condenser via a pressure loss member such as a capillary, and an absorbing liquid that absorbs the refrigerant evaporated in the evaporator. An air-cooled absorber for charging, a refrigerant tank communicated with the condenser via a valve, and a dilute solution tank connected between the absorber and the regenerator. In an air conditioner using a direct connection pipe equipped with a check valve between the refrigerant tank and the dilute solution tank to prevent backflow to the refrigerant tank, the refrigerant in the process of concentrating the solution In the tank An air conditioner using an absorption refrigerating machine, characterized in that a passage part is provided which directly connects the refrigerant tank and the dilute solution tank in order to equilibrate the pressure of the part with the pressure of the evaporator.