JPH0798164A - Air conditioning system using absorption refrigerator - Google Patents

Abstract

(57) [Abstract] [Purpose] Evaporate all the refrigerant in the evaporator to maintain high efficiency. [Structure] The evaporator 10 is installed between an air intake duct 4 and a blower duct 3 that allow indoor air to pass therethrough. The regenerator 12 is heated by the burner 13 to separate the solvent water from the dilute solution. The control means (CPU) obtains the output of the blower fan 11 based on the set temperature and the room temperature from the sensor T1, calculates the evaporation amount in the regenerator 12 corresponding to this output, and further adapts to this evaporation amount. The combustion amount of the burner 13 is calculated to control the fuel. Therefore, the excess refrigerant is not supplied to the evaporator 10, and the operation with high efficiency can be maintained.

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, and more particularly to an air conditioner capable of maintaining good efficiency.

[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 to be evaporated. 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 cool the condenser and the absorber by an air cooling method instead of the water cooling method during the cooling operation, and the refrigerant is sent from the condenser to the evaporator without using a pump. A patent application has already been filed for an air conditioner having a cooling mode in which the evaporator is located in a passage through which the room air to be air-conditioned passes and the room air is cooled by directly contacting the outside of the evaporator with the pressure difference. (Japanese Patent Application No. 5-22351).

FIG. 4 shows an essential part of a modified example of an air conditioner using the single-effect absorption refrigerator proposed in the above application, and FIG.
Indicates the installation status of the air conditioner.

As shown in FIG. 5, the air conditioner includes an outdoor unit 1
The outdoor unit 1 is arranged outside the room 5 of the house to be air-conditioned with the configuration shown in FIG. 4, and the indoor unit 2 has only the outlet for cool air and the inlet for indoor air. It has and is arranged inside the chamber 5. The outdoor unit 1 and the indoor unit 2 are connected by a blower duct 3 for cold air and an intake duct 4 for indoor air. A blower fan 11 is provided at a predetermined place in the blower duct 3 or the intake duct 4. Reference numeral 6 denotes a remote controller for starting or stopping the operation of the air conditioner, setting or canceling automatic operation, setting the room temperature, setting the amount of cold air blown out, and the like.

The inside of the outdoor unit 1 has a structure as shown in FIG. 4, in which an aqueous lithium bromide solution is used as the absorbing liquid and water is used as the refrigerant.

The evaporator 10 is installed at a position where the blower duct 3 and the intake duct 4 are connected to each other. The inside of the evaporator 10 evaporates the refrigerant due to the depressurization action, and the latent heat of vaporization (vaporization heat) acts to cool it from the inside. I am supposed to receive it.

The regenerator 12 has a function of generating a refrigerant vapor by heating the absorbing solution (dilute solution) having a low concentration by absorbing the refrigerant by the burner 13 and concentrating the concentration of the absorbing solution. Fuel supply pipe 1 to burner 13
4, fuel gas is supplied, and the degree of combustion is adjusted by the fuel supply control valve 15.

The condenser 16 has a function of cooling the refrigerant vapor sent from the regenerator 12 by the air cooling fan 17 and liquefying it, and sending this liquefied refrigerant to the evaporator 10.

Reference numeral 18 denotes a refrigerant tank for controlling a total amount of the refrigerant circulating in the air conditioner and a part of the refrigerant for controlling the concentration of the dilute solution supplied to the regenerator 12. Yes, it is connected to the condenser 16 via the valve 5.

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 which has absorbed the refrigerant and has a low concentration is temporarily stored in the dilute solution tank 21.

Reference numeral 22 denotes heat for exchanging heat between the low-concentration low-concentration absorption liquid flowing from the dilute solution tank 21 to the regenerator 12 and the high-concentration high-temperature absorption liquid flowing from the regenerator 12 to the absorber 20. An exchanger, 23 is a pump that absorbs the refrigerant and sends out an absorbent having a low concentration from the dilute solution tank 21 to the regenerator 12, and 24 is one between the upstream side of the evaporator 10 and the downstream side of the condenser 16. A capillary provided between them or a pressure loss means corresponding thereto.

All of V1, V2, V3, V4 and V5 are regulating valves such as solenoid valves, and in particular V4 is a regulating valve having a check valve function.

The above air conditioner basically controls the temperature by controlling the pressure difference between the containers, except that the pump 23 is used to deliver the absorbing liquid from the absorber 20 to the regenerator 12. The refrigerant is sent out by the pressure difference and circulated.

[0020]

By the way, in such an air-cooling type air conditioner, when the air volume sent from the air duct is automatically changed in order to maintain the indoor environment faithfully to the set desired condition. Alternatively, the user may arbitrarily reduce the air volume. When the blown air volume is changed in this way, the heat quantity of the evaporator taken away by the blown air is reduced, and a part of the refrigerant passing through the evaporator is not vaporized and flows into the absorber as a liquid. Occur. Then, there is a problem that the operation cannot be performed in the optimum state and the efficiency is deteriorated.

The present invention has been made in view of the above points, and an evaporator for vaporizing a refrigerant, an absorbing liquid for absorbing the refrigerant, and an absorbing liquid for absorbing the refrigerant vapor vaporized by the evaporator into the absorbing liquid. And an evaporator is disposed in a passage for introducing indoor air to be cooled, and the indoor air is directly cooled, and then the cooled air is blown directly into the room to cool the room. An object of the present invention is to provide an air conditioner using a machine so that even when the amount of airflow into the room is reduced, the evaporator does not generate unevaporated refrigerant and can be constantly operated with high efficiency.

[0022]

In order to achieve the above object, the present invention arranges an evaporator for evaporating a refrigerant in a passage for introducing indoor air to be cooled and directly cools the indoor air, In an air conditioner using an absorption refrigerator that cools air by blowing the cooled air directly into a room through a duct, a blower installed in the passage or the duct, and introduced into the passage provided in the passage. Detecting means for detecting the temperature of the indoor air, a regenerator for heating the absorbing liquid to generate a refrigerant vapor from the absorbing liquid, a burner for heating the regenerator, an input room set temperature and the The air volume of the blower is calculated based on the temperature detected by the detection means, and the required evaporation amount in the evaporator is calculated from this air volume, and then the required heat amount of the burner adapted to the required evaporation amount is calculated. It was constructed air conditioning apparatus using an absorption refrigerating machine and a control means for controlling the fuel supply amount of the burner.

[0023]

According to the input set temperature and the intake air temperature detected by the detecting means, the cooling capacity required to keep the room at the set temperature, in other words, the air conditioning load is calculated, and the blower fan corresponding to the air conditioning load is calculated. Is calculated. Once the air volume is determined, the evaporation amount of the refrigerant required for such air volume is calculated, and the fuel supply amount of the burner that heats the regenerator is controlled so that the amount of refrigerant that matches this evaporation amount is obtained. The excess refrigerant is not supplied to the evaporator and the refrigerant does not flow into the absorber without being evaporated, so that the efficiency does not decrease.

[0024]

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

FIG. 2 shows a main part of an embodiment of an air conditioner using a single-effect absorption refrigerator according to the present invention, and FIG.
As in the conventional example, the installation state of the air conditioner according to the present invention is shown.

The mechanical structure of the air conditioner according to the present invention is shown in FIG.
Since it is the same as that shown in FIG. 3, the description thereof will be omitted and an electric circuit required for controlling the air conditioner will be described.

In FIG. 2, T1 is a sensor for detecting the indoor 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.

Further, the receiving unit 2a of the indoor unit 2 receives the setting signal from the controller 30 including the CPU, the memory and the driving circuit and the remote controller 6 (see FIG. 5), and the receiving unit 2a
And a communication controller 31 for receiving a signal from the sensor T1, T2, T3, T4.
From the communication controller 31 and the signals from the communication controller 31 to control the operations of the blower fan 11, the air-cooling fan 17, and the pump 23.

Further, the controller 30 is provided with control means (not shown) for adjusting the amount of gas supplied to the burner 13. The control means compares the room temperature t1 from the sensor T1 with the input set temperature t0, determines the air flow rate of the air blower fan 11 from this air conditioning load, and determines the air flow rate thus determined and the new air flow rate. When the output of the blower fan 11 decreases due to the set blown air amount, the required amount of the refrigerant is obtained by adapting to the reduced amount, and the heating amount of the regenerator 12, that is, the burner 1 is obtained from the required amount of the refrigerant.
The fuel supply control valve 15 for adjusting the amount of fuel supplied to the fuel cell 3 is controlled.

Next, 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.

Turn on the operation button of the remote controller 6,
Desired temperature, or by setting the desired air volume, the valve opens V3 (F-1), the absorption liquid from the dilute solution tank 21 by the motor M ₂ is driven pump 23 is sent to the regenerator 12 (F-2) . The other valves remain as they are. At this time, the CPU of the controller 30 determines whether or not the liquid level of the regenerator 12 has reached the specified level by looking at the signal from the sensor T3 (F-3). When the liquid level has reached the specified level, the fuel supply 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 valve V1 is opened, while the valve 2 is closed (F-6), and the blower fan 11 and the air cooling fan 17 are rotated (F-7). As a result, the refrigerant vapor sent from the regenerator 12 is liquefied in the condenser 16, and the liquefied refrigerant is evaporated by the pressure difference between the condenser 16 and the evaporator 10.
Pour into. The refrigerant evaporates (vaporizes) inside the evaporator 10, and a cooling action occurs due to the heat of vaporization. As a result, the air blown from the room through the intake duct 4 by the blower fan 11 comes into direct contact with the outside of the evaporator 10 to be cooled. The cooled air is sent to the indoor unit 2 through the air duct 3 and is blown into the room 5 as cold air to cool the room 5 (F-8).

In this cooling operation, the refrigerant vaporized in the evaporator 10 to become vapor flows into the absorber 20 and is absorbed therein by the absorbing liquid. The absorbing liquid that has absorbed the refrigerant and has a reduced concentration once enters the dilute solution tank 21 and then exchanges heat with the high-concentration absorbing liquid that is sent from the regenerator 12 by the pump 23 through the valve V3 and the heat exchanger 22. And regenerator 1
Sent to 2. This is the steady mode of cooling operation. During this time, the valve V5 is repeatedly opened and closed as needed.

Here, the control of the amount of generated refrigerant when the amount of air blown by the blower fan 11 is reduced will be described with reference to the flowchart of FIG.

First, it is judged whether or not the air volume of the blower fan 11 is manually set by the user (G-1). If it is set, the process proceeds to G-5. If it is not set, G- Go to 2. Then, the room temperature t1 from the sensor T1 and the set temperature t0 are input (G-2), and t
The air conditioning load is calculated from the temperature difference between 0 and t1 (G-3).
Next, the air flow rate suitable for the obtained air conditioning load is calculated (G
-4), The amount of evaporation required for the evaporator 10 is calculated from this air flow (G-5). When the amount of evaporation is obtained by calculation, the amount of heat of the burner 13 required to generate the amount of refrigerant in the regenerator is calculated (G-6), and the fuel supply control valve 15 is provided so as to obtain that amount of heat. Open and close to adjust (G-7).

Specifically, for example, in automatic driving, the room temperature t1 detected by the sensor T1 is the room set temperature t0.
When it becomes necessary to weaken the cooling capacity by approaching, or when the user inputs and sets from the remote controller 6 or the like so as to reduce the air volume, the output of the blower fan 11 becomes the room temperature t1 and the set temperature t0. The air volume into the room is lowered automatically by the relationship of, or forcedly according to the set value input by the user. Then, the intake duct 4
A small amount of air passes through the inside, and the amount of air contacting the evaporator 10 decreases, and the evaporator 10 cools, that is, the amount of heat absorbed by the evaporator 10 decreases, and the cooling capacity of the evaporator 10 becomes excessive. become. If the refrigerant is sent to the evaporator 10 as it is, not all of it is evaporated, and a refrigerant that flows into the absorber 20 as a liquid is generated. Therefore, based on the decreased air flow rate, the evaporator 10 required for this air flow rate Is calculated, the amount of refrigerant required for the evaporator 10 is calculated from the required amount of cooling, and the amount of heating in the regenerator 12 required to generate such an amount of refrigerant is calculated. Then, the fuel supply control valve 15 for supplying the fuel to the burner 13 is controlled by the controller 30 so as to match the heating amount.

Therefore, the fuel of the burner 13 is controlled so that the regenerator 13 does not generate excess refrigerant and is not sent to the evaporator 10, and only the required amount of refrigerant is constantly generated. The amount can be made equal to the required amount of refrigerant, and efficient operation can be achieved.

Next, the temperature and pressure of the container, the absorbing liquid, and the refrigerant in each part of the system during the cooling operation will be exemplified.

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 13-20- Dilute solution: 35-40 Concentration: 61 % Concentrated solution: 90 Concentration: 64.8% Then, returning to the flowchart of FIG. 3, when the operation button of the remote controller 6 is turned off (F-9), the blower fan 1
1. The air-cooling fan 17 is stopped (F-10), during which the refrigerant in the refrigerant tank 18 and the absorbing liquid in the regenerator 12 all flow 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. After a short time delay, the pump 23 stops (F-11), and the flow of all liquids in the entire system stops.

As described above, according to the air conditioner of the present embodiment, even if the air volume of the blower fan 11 is reduced, the combustion amount of the burner 13 is controlled to a value suitable for the reduced amount, and the regenerator 12 is controlled. Since the amount of generated refrigerant in the refrigerant is adjusted, excess refrigerant is sent to the evaporator 10 and the refrigerant remains liquid and the refrigerant is absorbed in the absorber 2.
The air conditioner can be operated efficiently without flowing into zero.

In the above embodiment, the coolant is water and the absorbing liquid is lithium bromide as in the conventional example, but the present invention is not limited to this, and other substances having the same function may be used.

[0042]

As described above, according to the present invention,
In an air conditioner using an absorption refrigerating machine, when the air flow rate is reduced, the required amount of refrigerant suitable for the reduced air flow rate is calculated, and the calorie of the regenerator that generates this required amount of air flow is obtained. Since the amount of fuel supplied to the regenerator is controlled by the method, excessive refrigerant is not generated in the regenerator and sent to the evaporator, and an optimal amount of refrigerant is always sent to the evaporator. The refrigerant can be prevented from flowing into the absorber as a liquid, and the air conditioner can always be operated with high efficiency.

[Brief description of drawings]

FIG. 1 is a flow chart of an air conditioner according to the present invention.

FIG. 2 is a block diagram of a main part of an embodiment of an air conditioner according to the present invention.

FIG. 3 is a flowchart of a steady mode of operation of the air conditioner according to the present invention.

FIG. 4 is a block diagram showing an example of a conventional air conditioner.

FIG. 5 is a diagram showing an installation state of an air conditioner.

[Explanation of symbols]

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

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Hideki Furukawa 1-21-18 Inaridai, Sakura City, Chiba Prefecture (72) Kanako Nakayama 7-39-10 Kanagawa Nakamatsu City, Chiba Prefecture

Claims (2)

[Claims] 1. An evaporator for vaporizing a refrigerant, and an absorber for storing an absorbing liquid for absorbing the refrigerant and absorbing the refrigerant vapor vaporized by the evaporator into the absorbing liquid, wherein the air to be cooled is introduced. Necessary for an evaporator in an air conditioner using an absorption chiller that cools the indoor air directly by placing an evaporator in a passage and then blows the cooled air directly into the room through a duct. An air conditioner using an absorption refrigerating machine, comprising: a control means for controlling a heating amount of a regenerator for separating the refrigerant from a dilute solution based on the amount of the refrigerant. 2. An evaporator for evaporating a refrigerant, and an absorber for accumulating an absorbing liquid for absorbing the refrigerant and absorbing the refrigerant vapor vaporized by the evaporator into the absorbing liquid, and introducing cooling target room air. An air conditioner using an absorption refrigerating machine, in which an evaporator is arranged in a passage to directly cool the indoor air, and then the cooled air is blown directly into the room to cool the room. A blower installed inside, a detecting means provided in the passage for detecting the temperature of the indoor air introduced into the passage, a regenerator for heating the absorbing liquid to generate a refrigerant vapor from the absorbing liquid, A burner that heats the regenerator, calculates the air volume of the blower based on the input set temperature in the room and the detected temperature from the detection means, and calculates the required evaporation amount in the evaporator from the air volume, afterwards An air conditioner using an absorption refrigerating machine, comprising: a control unit for calculating a heat quantity of the burner adapted to the required evaporation amount and controlling a fuel supply quantity of the burner.