JP3225155B2 - Absorption air conditioner - Google Patents

Description

Description: BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an absorption cooling / heating machine,
The present invention relates to an absorption air conditioner and a heater suitable for controlling the amount of refrigerant sprayed on a refrigerant spray type evaporator. 2. Description of the Related Art Conventionally, absorption air-conditioners mainly use an aqueous solution of lithium bromide as an absorption solution and water as a refrigerant. However, water has a low steam pressure of several mmHg at the operating temperature of the absorption air conditioner,
The pressure increase due to the water depth has a disadvantageous effect on evaporation. Therefore, a liquid film spraying type evaporator which is advantageous for evaporation with a small pressure difference is usually used. [0003] In the evaporator of the liquid film spraying type, a refrigerant is dispersed in the evaporator and flows down on the evaporative heat transfer tube, and then the refrigerant that has not been completely evaporated is recirculated in the evaporator. After flowing into the evaporator and flowing down on the evaporative heat transfer tube,
There are two methods: a method in which the refrigerant that has not been completely evaporated flows out to the absorber without being recirculated. The former will be described with reference to FIG. 7, and the latter will be described with reference to FIG. FIG. 7 is a cycle diagram of a conventional absorption air conditioner, and FIG. 8 is a cycle diagram of another conventional absorption air heater. First, in FIGS. 7 and 8, 1 is a high temperature regenerator, 2 is a low temperature regenerator, 3 is a condenser, 4 is an evaporator, 5 is an absorber, 7 is a solution pump, 8 is an ejector, and 9 is a low temperature. A heat exchanger, 10 is a high-temperature heat exchanger, 11 is a boiler serving as a heat source of the high-temperature regenerator 1, 16 is a refrigerant vapor pipe connecting the high-temperature regenerator 1 and the low-temperature regenerator 2, and 15 is a refrigerant vapor pipe 16 The control valve 21 is a refrigerant spraying device in the evaporator 4, and 22 is
The solution spraying device 24 in the absorber 5 is a high-temperature regenerator 1
Vapor pipe connecting the evaporator 4 to the evaporator 4, 23 is a control valve of the refrigerant vapor pipe, 25 is a cold water pipe communicating with a heat transfer pipe of the evaporator 4, 26 is communicating with a heat transfer pipe of the absorber 5 and the condenser 3. Cooling water piping. [0005] In the conventional absorption air conditioner shown in FIG. 7, a refrigerant pump 44 is provided in a refrigerant pipe below the evaporator 4. That is, the refrigerant sprayed in the evaporator 4 is:
The refrigerant which has flowed down on the evaporative heat transfer tube 4a through which the cold water flows and has not been completely evaporated flows down the evaporative heat transfer tube 4a again through the refrigerant dispersion device 21 by the refrigerant pump 44. In this method, the amount of the refrigerant flowing down the evaporative heat transfer tube can be increased, the unevenness of the flow of the flowing down refrigerant in the axial direction of the heat transfer tube can be reduced, and the amount of the refrigerant flowing from the condenser 3 to the evaporator 4 can be reduced. There are advantages such as no need for control. [0008] In another conventional absorption air conditioner shown in FIG. 8, a refrigerant pipe connecting the condenser 3 and the evaporator 4 is provided with a flow control valve 19. The refrigerant whose flow rate has been adjusted by the flow control valve 19 flows into the evaporator 4, and is sprayed by the refrigerant spraying device 21 onto the evaporative heat transfer tube 4 a through which the cold water flows. At this time, the evaporation amount of the refrigerant is a function of the refrigeration load and the concentration of the absorbing solution, and is adjusted to a flow rate at which all of the refrigerant is supposed to evaporate. As it reaches the bottom of the evaporator 4 as it is, it flows into the absorber 5 as it is and is mixed with the absorbing solution. As described above, after flowing into the evaporator from the condenser and flowing down on the evaporative heat transfer tube, the refrigerant that has not been completely evaporated is recycled to the absorber without being recirculated. In the outflow method, the refrigerant flowing into the absorber is called an ineffective refrigerant, and the concentration of the absorbing solution in the absorber is reduced without exerting the refrigerating ability. [0008] The absorption cooling / heating machine exerts the refrigerating capacity by the energy of the difference in concentration between the refrigerant and the absorbing solution. As the amount of the ineffective refrigerant increases, the cooling efficiency of the entire absorption cooling / heating machine decreases. Further, the amount of the refrigerant evaporated in the evaporator differs depending on the magnitude of the cooling load at that time. If the amount of refrigerant sprayed is constant, if the cooling load is reduced, the amount of refrigerant that evaporates decreases, and the amount of ineffective refrigerant increases accordingly,
The cooling efficiency of the entire absorption air conditioner will be reduced. Therefore, it is indispensable to control the amount of the refrigerant sprayed on the evaporator. As a method of controlling the amount of refrigerant to be sprayed, for example,
As described in JP-A-3-211371, the temperature of the refrigerant in the evaporator is detected, and when the temperature is low, the amount of the refrigerant sprayed is increased. When the temperature is high, the amount of the refrigerant sprayed is reduced. Methods for reducing are known. But,
In this method, when the refrigerant load is large, the amount of refrigerant sprayed is increased, and when the refrigerant load is small, the amount of refrigerant sprayed can be controlled to be small, and the amount of ineffective refrigerant can be reduced to some extent. Depending on the conditions such as the temperature of the cooling water, the amount of the sprayed refrigerant may be insufficient or excessive, and therefore, the optimum control of the amount of the sprayed refrigerant may not be achieved. The present invention has been made in order to solve the above-mentioned problems of the prior art. Even if the amount of refrigerant evaporating in the evaporator changes depending on the state of the refrigeration load, the amount of ineffective refrigerant flowing into the absorber is reduced. It is an object of the present invention to provide a high-efficiency and low-cost absorption air conditioner that can minimize the temperature. [0011] To achieve the above object, a first aspect of the invention relating to an absorption air conditioner of the present invention comprises:
Having a liquid film spraying type evaporator, the refrigerant that could not evaporate is recirculated without recirculation or only part of it, and the refrigerant flows out of the evaporator as a liquid and is mixed with the absorbing solution The absorption cooling / heating machine is provided with a detecting means for detecting the flow rate of the outflowing refrigerant and a refrigerant spraying amount adjusting means for controlling the spraying amount of the refrigerant in the evaporator so as to keep the outflowing refrigerant flow rate constant . [0012] In order to achieve the above object, a second aspect of the invention relating to an absorption cooling / heating device of the present invention has a liquid film spraying type evaporator and does not recirculate the refrigerant that has not been completely evaporated. Or a part of the refrigerant is recirculated so that the refrigerant flows out of the evaporator in a liquid state and mixes with the absorbing solution. A detecting means for detecting the level of the liquid level of the refrigerant to be performed and a refrigerant spray amount adjusting means for controlling the refrigerant spray amount in the evaporator so as to keep the liquid level constant . The function of each of the above technical means is as follows. According to the first aspect, as components of the evaporator, detection means for detecting an outflow amount of the refrigerant that has not been completely evaporated in the evaporator, and refrigerant distribution amount adjusting means for controlling the refrigerant distribution amount in the evaporator By having
That the can the amount of the refrigerant flowing out so as to maintain constant, to minimize the amount of refrigerant wastefully flowing out from the evaporator
Wear. [0014] According to the second invention, as a component of the evaporator, a valve for a fixed amount of refrigerant flowing out from the evaporator, the liquid level of the refrigerant accumulated in the upper portion of the valve Detecting means, and a refrigerant spray amount adjusting means for controlling the spray amount of the refrigerant in the evaporator so as to keep the liquid level at a constant level. At this time, the refrigerant liquid level detecting means and the refrigerant spray amount If the adjusting means is constituted by a float valve, the control system can be simplified and the cost required for these can be reduced. Embodiments of the present invention will be described below with reference to FIGS. 1 to 6. First, an embodiment of the first invention will be described. Embodiment 1 FIG. 1 is a cycle diagram of an absorption air conditioner according to one embodiment of the present invention. In the figure, the same reference numerals as those in FIG. 7 indicate the same parts as those in the prior art. Note that arrows indicate the flow directions of the refrigerant, the absorbing solution, the chilled water, the chilled water, and the like, and the connection relationship of the electrical control system is indicated by a broken line. The absorption air conditioner shown in FIG. 1 includes a high-temperature regenerator 1, a low-temperature regenerator 2, a condenser 3, an evaporator 4, an absorber 5, a solution pump 7, an ejector 8, a low-temperature heat exchanger 9, a high-temperature heat exchange It comprises a vessel 10 and a piping system operatively connecting them. The cold water in the cold water pipe 25 flows through the evaporative heat transfer tube 4a in the evaporator 4. The cooling water of the cooling water pipe 26 flows through the heat transfer tubes 5 a and 3 a of the absorber 5 and the condenser 3. The absorption air conditioner of this embodiment has a different configuration as follows from the prior art shown in FIG. In FIG. 1, reference numeral 6 denotes a refrigerant receiver provided at the bottom of the evaporator 4;
Is a flow control valve provided in a refrigerant pipe connecting the condenser 3 and the evaporator 4. The flow control valve 19 controls the amount of refrigerant sprayed in the evaporator 4. Also, 20
Is a flow control valve provided in a refrigerant pipe connecting the condenser 3 and the absorber 5. 28 is a flow meter relating to a means for detecting the flow rate of the refrigerant flowing out of the evaporator 4, and 27 is an ejector. The ejector 27 controls the refrigerant flowing out of the evaporator 4 by the solution pump 7 at the outlet of the absorber 5. It functions as a suction mixing means for mixing with the discharged absorbing solution. Here, when the absorbing solution discharged from the absorber 5 by the solution pump 7 branches into one that flows into the regenerator and one that partially recirculates to the absorber, the evaporator 4 The position of the ejector 27 for mixing the outflowing refrigerant with the absorbing solution is provided on the regenerator side from this branch. Reference numerals 30a and 30b denote temperature sensors provided at the entrance and exit of the chilled water pipe 25 with respect to the evaporator 4, and 29 denotes flow control valves 19 and 20, a flow meter 28, and temperature sensors 30a and 30.
b, a controller electrically connected to the boiler 11 and the like of the high temperature regenerator 1 as shown by a broken line. The operation of the absorption air conditioner having such a configuration will be described. The refrigerant vapor generated in the high-temperature regenerator 1 and sent to the low-temperature regenerator 2 by the refrigerant vapor pipe 16 flows into the low-temperature regenerator 2 from the absorber 5 via the solution pump 7 via the solution spraying device 14. The refrigerant exchanges heat and condenses while evaporating the refrigerant vapor from the absorption solution. The refrigerant becomes a liquid refrigerant and is decompressed by the orifice 18 and flows into the condenser 3. The refrigerant vapor evaporated in the low-temperature regenerator 2 exchanges heat with the cooling water flowing in the condensing heat transfer tube 3a in the condenser 3, and condenses while heating the cooling water. The refrigerant condensed in the condenser 3 is supplied to the flow control valve 1
9, flows into the evaporator 4, is dispersed on the evaporative heat transfer tube 4 a by the refrigerant dispersing device 21, exchanges heat with cold water flowing in the evaporative heat transfer tube 4 a, evaporates while cooling the cold water, and absorbs as steam. Outflow into vessel 5. The refrigerant that has not been completely evaporated by the evaporator 4 is received by the refrigerant receiver 6, and then mixed with the absorbing solution as a liquid. The refrigerant vapor generated in the evaporator 4 is supplied to the absorber 5
Is absorbed by the absorbing solution flowing down on the absorption heat transfer tube 5a in the inside,
The absorption heat generated at this time is removed by the cooling water flowing in the absorption heat transfer tube 5a. The absorbing solution flowing down in the absorber 5 is
Low temperature heat exchanger 9 and high temperature heat exchanger 10 by solution pump 7
Is sent to the high-temperature regenerator 1 through the low-temperature heat exchanger 9 and to the low-temperature regenerator 2 via the low-temperature heat exchanger 9. A part of the absorption solution is recirculated to the absorber 5 through the ejector 8. The absorbing solution sent from the absorber 5 to the high-temperature regenerator 1 while the flow rate is adjusted by the float valve 12 in the float box 13 is heated by the boiler 11 in the high-temperature regenerator 1 and partly turns into refrigerant vapor. The concentrated absorption solution flowing into the low-temperature regenerator 2 is mixed with the concentrated absorption solution returned from the low-temperature regenerator 2 through the high-temperature heat exchanger 10 and sprayed through the low-temperature heat exchanger 9 and the ejector 8. A flow-down cycle is configured to the absorber 5 via the device 22. Among the functions of the absorption air conditioner, the features of the present embodiment will be further described. In the absorption cooler / heater shown in FIG. 1, in order to optimally control the amount of refrigerant sprayed in the evaporator 4, the refrigerant liquid is sprayed on the evaporative heat transfer tubes 4a and the evaporative heat transfer tubes 4a.
When the refrigerant exchanges heat with the cold water flowing in a and evaporates while cooling the cold water, the refrigerant that has not completely evaporated is collected by the refrigerant receiver 6, via the refrigerant pipe connected to the refrigerant receiver 6, and via the ejector 27, The solution is mixed with the absorbing solution discharged from the absorber 5 by the solution pump 7. The amount of the refrigerant mixed into the absorbing solution is measured by the flow meter 2
8 and the flow rate of the refrigerant is controlled by the flow control valve 19 so that the flow rate is constant. If this flow rate is determined to be, for example, about 1% of the total circulation amount of the refrigerant, the refrigeration efficiency of the absorption cooling / heating machine does not decrease by 1% or more. In addition, if the opening degree of the flow control valve 19 at this time is small, it can be considered that the refrigeration capacity is small, so that it is possible to control the output of the boiler 11 in the high temperature regenerator 1 to be small. Further, by comparing the chilled water temperature detected by the temperature sensors 30a and 30b provided in the chilled water pipe 25 with the valve opening of the flow control valve 19, the change in the flow rate of the chilled water can be indirectly measured. It becomes possible. The flow control valve 20 prevents accidents such as absorption solution crystals and refrigerant freezing by mixing the refrigerant with the absorption solution when the absorption cooling / heating machine is stopped or when the absorption solution is excessively concentrated. is there. According to the present embodiment, by performing the above control by the controller 29, even if the refrigerant evaporation amount in the evaporator changes due to the state of the refrigeration load of the absorption cooling / heating machine, the ineffective refrigerant amount is reduced. The amount of refrigerant circulating can be maintained at about 1%, and there is an effect of preventing the efficiency of the absorption cooling / heating machine from being reduced due to a change in the refrigeration load. Thus, it is possible to provide an absorption cooling / heating machine with higher efficiency than before. Embodiment 2 FIG. 2 is a cycle system diagram of an absorption cooling / heating machine according to another embodiment of the present invention (first invention). In the figure, those having the same reference numerals as those in FIG. 1 indicate the same parts as those in the first embodiment, and the description thereof will be omitted. The embodiment of FIG. 2 differs from the embodiment of FIG. 1 in that a refrigerant pipe connecting the condenser 3 and the absorber 5 with the flow control valve 20 is not provided. In the present embodiment, when the absorption cooler / heater is stopped, or when the absorption solution is excessively concentrated, the controller 31 controls the operation of mixing the refrigerant with the absorption solution in order to prevent accidents such as absorption solution crystals and refrigerant freezing. This is performed only by the flow control valve 19. According to this embodiment, the same effects as those of the first embodiment can be obtained. [Embodiment 3] FIG. 3 is a cycle system diagram of an absorption air conditioner according to still another embodiment of the present invention (first invention). In the figure, those having the same reference numerals as those in FIG. 1 indicate the same parts as those in the first embodiment, and the description thereof will be omitted. The embodiment of FIG. 3 differs from the embodiment of FIG. 1 in that, in order to mix the refrigerant flowing out of the evaporator 4 into the absorbing solution, the mixing point is set closer to the absorber 5 by the solution pump 7 at the outlet of the absorber 5. It is configured to be provided. In FIG. 3, reference numeral 50 denotes a refrigerant receiver 6.
Refrigerant pipe having a flow meter 28 connected to the
The junction with the absorption solution pipe on the side of the absorber 5, that is,
This is the mixing point where the refrigerant that has not completely evaporated mixes into the absorbing solution. In the absorption cooler / heater shown in FIG. 3, when the refrigerant sprayed on the evaporative heat transfer tube 4a exchanges heat with the cold water flowing in the evaporative heat transfer tube 4a and evaporates, the refrigerant that has not been completely evaporated receives the refrigerant. The water is collected by the cooling medium 6, and is mixed with the absorbing solution discharged from the absorber 5 at the mixing point 50 through the refrigerant pipe connected to the cooling medium receiver 6. The amount of the refrigerant mixed into the absorbing solution is measured by the flow meter 28, and the amount of the refrigerant sprayed is controlled by the flow regulating valve 19 so that the flow rate becomes constant. Each control in the embodiment of FIG.
Done by According to this embodiment, the same effects as those of the first embodiment can be obtained, and there is an advantage that the ejector 27 shown in FIG. 1 becomes unnecessary. However, in the case of the present embodiment, the concentration of the absorbing solution that is recirculated and sprayed into the absorber 5 via the ejector 8 becomes thin, and the amount of heat exchange with the cooling water in the absorber 5 decreases. Must be taken into account. Next, an embodiment of the second invention will be described. Embodiment 4 FIG. 4 is a cycle diagram of an absorption air conditioner according to an embodiment of the present invention (second invention). In the figure, those having the same reference numerals as those in FIG. 1 indicate the same parts as those in the first embodiment, and the description thereof will be omitted. In FIG. 4, reference numeral 33 denotes a refrigerant tank provided on a refrigerant pipe connected to the refrigerant receiver 6 of the evaporator 4, and reference numeral 34 denotes a flow control valve provided below the refrigerant tank 33. In the absorption air conditioner shown in FIG. 4, a part of the refrigerant flowing out of the evaporator 4 without being completely evaporated in the evaporator 4 is temporarily stored in a refrigerant tank 33, and when the absorption air conditioner is stopped, or Is controlled to be mixed with the absorbing solution via the flow rate regulating valve 34 when excessively concentrated. Each control in the embodiment of FIG. 4 is performed by the controller 35. According to this embodiment, the same effects as those of the first embodiment can be obtained. In particular, when the absorption solution is excessively concentrated by stopping the absorption air conditioner or the partial load operation. Since the absorption solution can be diluted by mixing the refrigerant stored in the refrigerant tank 33 with the absorption solution, the ineffective refrigerant can be effectively used, and energy can be saved as a whole. [Embodiment 5] FIG. 5 is a cycle diagram of an absorption air conditioner according to another embodiment of the present invention (second invention). In the figure, those having the same reference numerals as those in FIG. 1 are the same as those in the absorption air conditioner of the first embodiment, and therefore the description thereof is omitted. In FIG.
36 is a float valve provided on the refrigerant receiver 6 of the evaporator 4;
Reference numeral 5 denotes a flow control valve provided in a refrigerant pipe connected to the refrigerant receiver 6, and the flow control valve 45 is for keeping the flow rate of the refrigerant flowing out constant. In the absorption cooler / heater shown in FIG. 5, the amount of the refrigerant to be sprayed can be adjusted by the float valve 36 so that the liquid level on the refrigerant receiver 6 becomes constant. Since the amount of refrigerant flowing out of the vessel 4 is made constant, the amount of ineffective refrigerant can be minimized. Each control in the embodiment of FIG. 5 is performed by the controller 37. According to this embodiment, the same effects as those of the first embodiment can be obtained, the control system can be simplified, and the cost for these can be reduced. The refrigerant flow control method of the present invention is applicable not only to a water-cooled absorption refrigerator but also to an air-cooled absorption refrigerator.
FIG. 6 shows the embodiment. Embodiment 6 FIG. 6 is a cycle system diagram of an air-cooled absorption air conditioner according to still another embodiment of the present invention. In the figure, those having the same reference numerals as those in FIG. 1 are the same as those in the absorption air conditioner of the first embodiment, and therefore the description thereof is omitted. In FIG. 6, reference numeral 38 denotes an air cooling fin constituting the air-cooled condenser 3A, and 39 denotes an air cooling fin 38.
, An air cooling fin provided in the absorption solution pipe of the air-cooled absorber 5A, 41 a fan for ventilating the air-cooled fin 40, 42 a solution spraying device in the air-cooled absorber 5A It is. The refrigerant receiver 6 provided in the evaporator 4, the flow meter 28 relating to the means for detecting the flow rate of the refrigerant flowing out of the evaporator 4, the refrigerant flowing out of the evaporator 4
The structure and operation of the ejector 27 and the like which function as suction mixing means for mixing with the absorbing solution discharged by the solution pump 7 at the outlet of the absorber 5 are the same as those in the embodiment of FIG. Each control in the embodiment of FIG. 6 is performed by the controller 43. According to the air-cooled absorption air conditioner shown in FIG.
In addition to obtaining the same effects as in the first embodiment, in the case of air cooling, the effect of the present invention is further enhanced as compared with water cooling, since the refrigeration cycle is particularly susceptible to changes in the outside air temperature. As described above in detail, according to the present invention, even if the refrigerant evaporation amount in the evaporator changes due to the state of the refrigerating load, the amount of the ineffective refrigerant flowing into the absorber is reduced. It is possible to provide a high-efficiency and low-cost absorption air conditioner that can be held down to a minimum.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a cycle diagram of an absorption air conditioner according to one embodiment of the present invention. FIG. 2 is a cycle system diagram of an absorption air conditioner according to another embodiment of the present invention. FIG. 3 is a cycle system diagram of an absorption air conditioner according to still another embodiment of the present invention. FIG. 4 is a cycle system diagram of an absorption air conditioner according to still another embodiment of the present invention. FIG. 5 is a cycle system diagram of an absorption air conditioner according to still another embodiment of the present invention. FIG. 6 is a cycle diagram of an air-cooled absorption air conditioner according to still another embodiment of the present invention. FIG. 7 is a cycle system diagram of a conventional absorption cooling / heating machine. FIG. 8 is a cycle diagram of another conventional absorption air conditioner. [Description of Signs] 1 ... High temperature regenerator, 2 ... Low temperature regenerator, 3 ... Condenser, 3A ...
Air-cooled condenser, 3a condensation heat transfer tube, 4 evaporator, 4a evaporation heat transfer tube, 5 absorber, 5A air-cooled absorber, 5a absorption heat transfer tube, 6 refrigerant receiver, 7 solution pump, 9 ... Low-temperature heat exchanger, 10 ... high-temperature heat exchanger, 19, 20, 34, 45 ...
Flow control valve, 21: refrigerant spraying device, 22, 42: solution spraying device, 25: cold water piping, 26: cooling water piping, 27: ejector, 28: flow meter, 33: refrigerant tank, 36: float valve, 38, 40: air cooling fins, 39, 41: fan, 50: mixing point.

──────────────────────────────────────────────────続 き Continued on the front page (72) Inventor Tomihisa 502, Kandate-cho, Tsuchiura-shi, Ibaraki Pref. Machinery Research Laboratory, Hitachi, Ltd. (56) References JP-A-3-211371 (JP, A) Japanese Utility Model Application Sho 54-155656 (JP, U) Japanese Utility Model Application Utility Model Sho 52-150849 (JP, U) (58) Fields investigated (Int. . ^7, DB name) F25B 15/00 306

Claims (1)

(57) [Claims 1] A refrigerant having a liquid film spraying type evaporator, and without recirculating a refrigerant that has not completely evaporated, or by recirculating only a part thereof, In the absorption air conditioner, which flows out of the evaporator as a liquid and mixes with the absorbing solution, a detecting means for detecting the flow rate of the refrigerant flowing out, and controlling the amount of refrigerant sprayed in the evaporator so as to keep the flow rate of the refrigerant flowing out constant An absorption air conditioner comprising: 2. A liquid film dispersing type evaporator having a refrigerant that has not been completely evaporated without recirculating the refrigerant or recirculating only a part of the refrigerant so that the refrigerant flows out of the evaporator as a liquid. In an absorption air conditioner that mixes with an absorption solution, a valve for making the flow rate of the refrigerant flowing out constant, a detecting means for detecting a liquid level of the refrigerant stored in an upper portion of the valve, and a liquid level height for the refrigerant An absorption air-conditioning and heating machine comprising a refrigerant spray amount adjusting means for controlling a refrigerant spray amount in an evaporator so as to keep the refrigerant spray amount constant. 3. A regenerator for generating a refrigerant vapor, a condenser for condensing the refrigerant vapor generated by the regenerator, a liquid film spraying type evaporator for spraying the liquid refrigerant condensed by the condenser, and an evaporator. An absorber in which an absorbing solution that absorbs the refrigerant evaporated in the above is stored, a solution heat exchanger that preheats the absorbing solution, and a solution pump that is arranged in a pipe connecting the solution heat exchanger and a lower portion of the absorber. In the absorption air conditioner, the refrigerant that has not completely evaporated in the evaporator is absorbed by the absorbing solution without being returned to the evaporator, or only a part of the refrigerant is returned to the evaporator. A refrigerant receiver for collecting the refrigerant that could not be exhausted, a flow detecting means arranged near the refrigerant receiver for detecting the amount of the refrigerant that has not completely evaporated flowing into the refrigerant receiver, and an upstream or downstream side of the solution pump. At least The refrigerant pipe connected to the refrigerant receiver via the flow rate adjusting means for adjusting the flow rate of the refrigerant flowing into the evaporator from the condenser, which merges with the pipe on one side, and the evaporation detected by the flow rate detecting means could not be completed. A control unit for controlling the flow rate adjusting unit based on the amount of the refrigerant. A regenerator for generating a refrigerant vapor, a condenser for condensing the refrigerant vapor generated in the regenerator, a liquid film spraying type evaporator for spraying the liquid refrigerant condensed in the condenser, and an evaporator. An absorber in which an absorbing solution for absorbing the evaporated refrigerant is stored, a solution heat exchanger for preheating the absorbing solution, and a solution pump disposed in a pipe connecting the solution heat exchanger and a lower portion of the absorber. Wherein the refrigerant that has not completely evaporated in the evaporator is absorbed in the absorbing solution without being returned to the evaporator, or only a part of the refrigerant is returned to the evaporator. A refrigerant receiver that collects the refrigerant that did not exist, a refrigerant liquid level detecting unit that detects the amount of refrigerant that has flowed into the refrigerant receiver, and merges with at least one of the upstream and downstream pipes of the solution pump to evaporate from the condenser. Refrigerant flowing into the vessel A refrigerant pipe connected to the refrigerant receiver via a flow rate adjusting means for adjusting the amount, and a control means for controlling the flow rate adjusting means based on the amount of refrigerant that has not completely evaporated detected by the refrigerant liquid level detecting means. An absorption air conditioner, which is provided. 5. The absorption cooling / heating machine according to claim 3, wherein the junction forms an ejector. 6. A branching section for branching the absorbing solution discharged from the solution pump into the regenerator and the absorber, and the merging section is provided on the regenerator side from the branching section. The absorption cooling / heating machine according to claim 3 or 4. 7. The absorption air conditioner according to claim 3, wherein the refrigerant flowing out of the evaporator is mixed with the absorption solution in the absorber or between the absorber and the solution pump. 8. A refrigerant tank for storing the refrigerant flowing out of the evaporator, and the refrigerant stored in the refrigerant tank can be mixed with the absorption solution when the absorption cooling / heating unit is stopped or when the absorption solution is excessively concentrated. The absorption cooling / heating machine according to claim 3 or 4, further comprising a control valve for setting the temperature. 9. The absorption air conditioner according to claim 4, wherein said refrigerant liquid level detecting means and flow rate adjusting means are float valves.