JPH04295558A - Absorption refrigerator - Google Patents

Abstract

PURPOSE:To provide an absorption refrigerator of a small capacity for domestic use or the like in which even dilution can obtained. CONSTITUTION:A refrigerant tank 7 ranging with a vaporizer 6, a regenerator 1 and float sensors 15 and 25 are provided, and a solution tank 18 is connected to the refrigerant tank 7 through a refrigerant circulation pump 16 and a main dilution valve 17. In addition, in a piping between the solution tank 18 and a solution heat exchanger 13, a solution circulation pump 20, a diluted solution valve 21 and a subsidiary dilution valve 22 are provided. The subsidiary dilution valve 22, the solution circulation pump 20, the refrigerant circulation pump 16, the main dilution valve 17, the float sensors 15 and 25 and an outdoor temperature sensor 23 are all communicated with a controller 24 so as to obtain a correct dilution.

Description

[Detailed description of the invention]

0001

BACKGROUND OF THE INVENTION 1. Field of the Invention This invention relates to a small-capacity absorption refrigerating machine for domestic or nearby use.

0002

[Prior Art] In a conventionally used absorption refrigerating machine consisting of an absorber, a regenerator, a condenser, and an evaporator, which is equivalent to 10 refrigeration tons, the solution circulation pump and refrigerant circulation pump are operated for a certain period of time after stopping. In many cases, the solution is diluted by continuing operation, reducing the concentration by absorbing refrigerant vapor in the absorber, and mixing and stirring a concentrated solution and a dilute solution.

0003

[Problem to be solved by the invention] However, in this case, the flow on the concentrated liquid side depends on the residual pressure difference, but in a small-capacity absorption refrigerator, the heat capacity is also small, so gas combustion is stopped by the shutdown operation. The pressure in the regenerator will drop quickly and it will be difficult for it to remain. For this reason, sufficient dilution cannot be expected, and the concentration after dilution also varies. In addition, as a conventional means of preventing abnormal operation, if the signal from the liquid level detector of the evaporator, absorber, or regenerator indicates that crystals are likely to occur during operation, the refrigerant or dilute solution is injected into the concentrated solution system. It is also known that a substance can be introduced to create a situation in which crystallization is not induced (see Japanese Patent Publication No. 17338-1973).

In view of the above circumstances, the present invention has been developed by discharging the refrigerant into the absorption liquid up to a predetermined level of the refrigerant in the refrigerant tank so that the solution does not crystallize during the stoppage, and keeping the concentration after dilution at a constant value. The above problem is solved by diluting the liquid by mixing and stirring in the same way as before, and then diluting it in the regenerator and solution heat exchanger for a predetermined period of time, and stirring so that the entire absorption liquid has a nearly uniform concentration. The purpose of this invention is to provide an absorption refrigerator that

[0005]

[Means for Solving the Problems] The present invention provides an absorption refrigerator comprising an absorber, a regenerator, a condenser, and an evaporator.
a solution tank that stores the dilute solution derived from the absorber;
It has a refrigerant tank that stores the refrigerant in the evaporator, and a dilution pipe line from the refrigerant tank to the solution tank is provided with a refrigerant circulation pump and a main dilution valve, and a dilution pipe line from the solution tank to the regenerator is provided. A solution pump is installed in the condensed solution line from the regenerator to the solution tank, and an auxiliary dilution valve is installed in the concentrated solution conduit from the regenerator to the solution tank. It is equipped with a controller for operating a refrigerant circulation pump, a main dilution valve, a solution pump, and a sub-dilution valve.

[0006]

[Operation] Due to the above configuration, when the operation stop signal is input at the end of operation, the refrigerant circulation pump continues operation if the liquid level in the refrigerant tank is above a predetermined value a (usually above a). The main dilute valve is opened and the refrigerant is sent to the solution tank and diluted. Furthermore, when the liquid level in the refrigerant tank falls below a, the refrigerant circulation pump stops and the main dilution valve closes. On the other hand, on the absorption liquid side, only the combustion device is stopped for S1 minutes after the stop, and the solution circulation pump and others continue to operate. The diluted solution in the solution tank is sent by a solution circulation pump and is sequentially diluted in the solution heat exchanger, regenerator, solution heat exchanger, absorber, and solution tank. However, during this time, the dilute solution valve is closed when the regenerator float sensor is a Hi signal, and opened when it is a Lo signal to control the flow rate. This solution circulation pump continues Hi operation.

[0007] The sub-dilution valve is kept open for S1 to S2 minutes after stopping. The absorption liquid is circulated through a solution tank, a solution heat exchanger, a regenerator, a solution heat exchanger, an auxiliary dilution valve, and a solution tank by a solution circulation pump to further equalize the concentration and dilute it. S2
After a few minutes, the sub-dilution valve will be open, so all the absorbent in the regenerator, solution heat exchanger, and piping will fall into the solution tank. Dilutions made during times other than the cooling season (for example, winter) and dilutions made during the cooling season have relatively high concentrations because the outside air temperature is high, making it difficult to crystallize, and to start the cooling operation sooner the next time. Perform dilution only to the extent that That is, since crystals will occur in winter if the concentration remains unchanged, further dilution is automatically performed as winter approaches, depending on the outside temperature.

In this case, when the outside air temperature t° C. is detected by the outside air temperature sensor, the refrigerant circulation pump is operated, the main dilution valve is opened, and the refrigerant is discharged and diluted into the solution tank until the refrigerant liquid level reaches l. On the other hand, on the absorption liquid side, the solution circulation pump is operated in Hi mode and the sub-dilution valve is left open to make the concentration uniform as described above.
Run for 3 minutes and then stop. Once you perform this operation, it will be remembered and you will never perform it again.

[0009]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be explained below based on drawings of embodiments.

FIG. 1 shows a refrigeration cycle system diagram of a small-capacity water-lithium salt absorption refrigerating machine for household use, in which the absorber and condenser are air-cooled or water-cooled. This is a regenerator that generates a concentrated solution and refrigerant vapor, with a combustion device 2 disposed at the bottom thereof, and a condenser 3 that uses refrigerant vapor as a refrigerant liquid is connected to the regenerator 1 via a pipe 4. The tip of a pipe 5 attached to the lower part of the evaporator 3 is connected to a refrigerant tank 7 provided at the lower part of the evaporator 6, and an absorber 9 is connected to the evaporator 6 through a pipe 8. On the other hand, a concentrated solution pipe 10 that guides the concentrated solution generated in the regenerator 1 has a concentrated solution valve 1 arranged in parallel.
1 and an orifice 12 to a solution heat exchanger 13, and the solution heat exchanger 13 is connected to the absorber 9 through a concentrated solution distribution device 14. 15 is a refrigerant float sensor provided in the refrigerant tank 7, which detects the liquid level a>h>l. The refrigerant circulation system includes a refrigerant circulation pump 16 and a main dilution valve 17 connected to a solution tank 18 serving as a dilute solution reservoir for guiding the dilute solution from the absorber 9, and a dilute solution piping 19 connected from the solution tank 18. The piping returns to the regenerator 1 via the solution circulation pump 20, the dilute solution valve 21, and the solution heat exchanger 13. 22 is a solution heat exchanger 13 and a solution tank 1
This is a sub-dilution valve installed in the pipe between the sub-dilution valve 22, the refrigerant float sensor 15, the refrigerant circulation pump 16, the main dilution valve 17, the solution circulation pump 20, and the pipe 4 facing the condenser 3. The outside air temperature sensors 23 are connected to a controller 24, and the whole becomes an absorption refrigerator. 25 is a regenerator float sensor provided on the side of the regenerator 1.

Next, to explain this effect, first, the regenerator 1
The diluted solution absorbed the refrigerant in the combustion device 2 is heated and boiled to produce a concentrated solution and refrigerant vapor. This concentrated solution passes through the concentrated solution piping 10 and the concentrated solution valve 11 and orifice 12 arranged in parallel in the same piping to the solution heat exchanger 13.
to go into. Further, the concentrated solution is distributed through the concentrated solution pipe 10 into the heat exchanger tube of the absorber 9 by the concentrated solution distribution device 14 . Absorber 9
The concentrated solution is evaporated in the evaporator 6, absorbs the refrigerant vapor introduced through the pipe 8, becomes a dilute solution, and enters the solution tank 18, which is a dilute solution reservoir, through the pipe 26. The dilute solution is passed through the dilute solution piping 19 and the solution circulation pump 2 installed in the middle.
0, passes through the dilute solution valve 21 and solution heat exchanger 13 and returns to the regenerator 1 again.

On the other hand, the refrigerant is evaporated in the regenerator 1, passes through the pipe 4, is cooled in the condenser 3, and is liquefied to become a refrigerant liquid. This refrigerant liquid is transferred through a pipe 5 to a refrigerant tank 7 which is a refrigerant liquid reservoir.
to go into. The refrigerant liquid in the refrigerant tank 7 passes through the pipe 27 and is dispersed onto the heat transfer tubes of the evaporator 6 from the refrigerant distribution device 28 by the refrigerant circulation pump 16 . The refrigerant liquid evaporates on this heat transfer tube, cools the cold water coming in from the cold water inlet pipe 29, and sends it out from the cold water outlet pipe 30. This cold water is used for indoor air conditioning. The evaporated refrigerant vapor enters the absorber 9 through the pipe 8 and is absorbed.

The absorber 9 and condenser 3 are cooled by air cooling or water/air cooling. The absorber 9,
Cool the condenser 3. In the case of a water-air cooling system, the cooling water in the cooling tank 32 is sprayed by the cooling water pump 33 through the cooling water piping 34 from the cooling water distribution device 35 to the absorber 9 or the condenser 3 for cooling.

[0014] In this case, ■ Stop dilution in the cooling season is
The refrigerant circulation pump 16 in the refrigerant tank 75 reaches the liquid level a.
The main dilution valve 17 is opened to dilute the solution (the solution is diluted to an average of 57%). To prevent the concentration from dropping too much and start the next cooling operation quickly. However, the liquid level a indicates the cooling season dilution stop position, the liquid level h indicates the liquid level at which the refrigerant circulation pump starts operating, and the liquid level l indicates the liquid level at which the refrigerant circulation pump stops.

[0015] In times other than the cooling season, (1) Since it remains stopped during the cooling season (concentration 57%), it is further automatically diluted. When the outside air temperature drops to t°C (for example, 5°C), the refrigerant circulation pump 16 is operated until the liquid level l and the main dilution valve 17 is opened.
Dilute as diluted.

■After all stops, including stops due to power outages, drain all the dilute and concentrated solutions in each pipe and route into the solution tank 1.
Return by natural fall within 8. ■Control in case of stoppage (cooling season) The refrigerant circulation pump 16 is operated until the refrigerant liquid level ~a, and the main dilution valve 17 is opened. Solution circulation pump 20 for S1 minute after stopping
When the regenerator float sensor 25 issues a Hi signal, the dilute solution valve 21 is closed, and when the regenerator float sensor 25 issues a Lo signal, the dilute solution valve 21 is opened. For S1 to S2 minutes after stopping, regenerator float sensor 2
When the regenerator float sensor 25 issues a Hi signal, the solution circulation pump 20 is operated at Lo, and when the regenerator float sensor 25 issues a Lo signal, the solution circulation pump 20 is operated at Hi. It opens and stops after S2 minutes.

[0017]

Effects of the Invention As described above, in the absorption chiller of the present invention, the refrigerant circulation pump, the main dilution valve, and the liquid Since the pump and the sub-dilution valve are operated, there is no variation in the concentration after dilution, the dilution time can be shortened, excessive dilution can be avoided, and the overall efficiency can be improved.

[Brief explanation of drawings]

FIG. 1 is a schematic diagram showing an embodiment of the present invention.

[Explanation of symbols]

1 Regenerator 3. Condenser 6 Evaporator 7 Refrigerant tank 9 Absorber 13 Solution heat exchanger 15 Refrigerant float sensor 16 Refrigerant circulation pump 17 Main dilution valve 18 Solution tank 19 Dilute solution piping 20 Solution circulation pump 21 Dilute solution valve 22 Sub-dilution valve 23 Outside temperature sensor 25 Regenerator float sensor

Claims (1)

[Claims] Claim 1: An absorption refrigerator comprising an absorber, a regenerator, a condenser, and an evaporator, comprising: a solution tank for storing a dilute solution derived from the absorber; and a refrigerant tank for storing refrigerant in the evaporator. A dilution pipe line from the refrigerant tank to the solution tank is provided with a refrigerant circulation pump and a main dilution valve, a solution pump is provided in the dilute solution pipe line from the solution tank to the regenerator, and a regenerator A sub-dilution valve is installed in the concentrated solution pipeline leading from to the solution tank, and when cooling operation is stopped, the refrigerant circulation pump, main dilution valve, and solution pump are activated depending on the height of the liquid level in the refrigerant tank and regenerator and the outside air temperature. and a controller for operating the auxiliary dilution valve.