JPH025990B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a heating/cooling switching device for an absorption refrigerator.

In particular, it is possible to easily switch between cooling and heating operations by operating a single cooling/heating switching valve, and is intended to prevent freezing of the refrigerant and crystallization of the absorption liquid during heating when the outside temperature is low.

Conventionally, in absorption chillers, during heating operation, hot water is taken out from the cooling water system of the absorber and condenser during cooling operation, so it is necessary to operate a large number of related cooling/heating switching valves on the machine's auxiliary equipment side. It was extremely complicated. Therefore, such a complicated cooling/heating switching valve is completely abolished and hot water is taken out from the evaporator's cold water system during cooling operation instead of the cooling water system.

That is, as shown in FIG. 1, the inside of the body 1 of the cylindrical body kept in a highly vacuum state is divided into upper and lower parts by a partition wall 2, and a low-temperature regenerator 5 is installed on the high-pressure side of the upper part.
and a condenser 6, and an absorber 3 and an evaporator 4 are housed on the lower low-pressure side, all of which are composed of a group of heat transfer tubes.

During cooling operation, the refrigerant sprayed onto the tube surface of the tube group of the evaporator 4 by the refrigerant liquid dispersion device 8 absorbs heat from the water flowing through the tubes of the evaporator 4 and evaporates.

This evaporated refrigerant vapor is absorbed by the concentrated absorption liquid that is sprayed onto the tube surface of the tube group of the absorber 3 by the absorption liquid distribution device 9. Due to this absorption action, the refrigerant in the evaporator 4 is continuously evaporated, and the water in the tube of the evaporator 4 is continuously cooled through the tube wall. Therefore, this cold water can be used for various cooling purposes.

The absorption liquid that has absorbed the refrigerant vapor is collected in the liquid reservoir 11 as a dilute absorption liquid. This diluted absorption liquid is absorbed by the absorption liquid pump 14.
The heat is passed through a pipe, passed through a low-temperature heat exchanger 12, heated by a high-temperature heat exchanger 13, and then guided to a high-temperature regenerator 7 through a pipe. This high-temperature regenerator 7 is filled with an absorption liquid until a predetermined liquid level is maintained. A group of heat transfer tubes is arranged to form a path for combustion gas, and when the absorption liquid is heated and boiled by the heat of combustion, a part of the water absorbed in the absorber 3 is evaporated and concentrated to become an intermediate concentration absorption liquid. This intermediate concentration absorption liquid flows out from the high temperature regenerator 7 into the pipe line, flows into the high temperature heat exchanger 13, where it exchanges heat with the dilute absorption liquid, and then is led to the low temperature regenerator 5, where it is The refrigerant is heated again by the refrigerant vapor flowing through the tube group, and the refrigerant evaporates and concentrates to become a highly concentrated absorption liquid. This high-concentration absorbent flows out from the low-temperature regenerator 5 and enters the low-temperature heat exchanger 12 through a pipe, where it exchanges heat with the dilute absorbent. It absorbs the refrigerant vapor from the evaporator 4, flows down to the liquid reservoir 11 again as a dilute absorption liquid, and repeats the reservoir circulation.

On the other hand, the refrigerant vapor evaporated in the high-temperature regenerator 7 flows through the pipe line into the tube group of the low-temperature regenerator 5, heats and concentrates the intermediate concentration absorption liquid from the high-temperature regenerator 7, and then flows into the condenser 6. It condenses and becomes a refrigerant liquid. This refrigerant liquid mixes with the refrigerant liquid accumulated in the refrigerant reservoir 10 and is dispersed from the refrigerant distribution device 8, and the refrigerant vapor that evaporates while flowing down the tube surface of the tube group of the evaporator 4 becomes an absorption liquid in the absorber 3. The absorbed but unevaporated refrigerant accumulates in the refrigerant reservoir 10.

The refrigerant liquid then passes through the pipe and is returned to the refrigerant distribution device 8 by the refrigerant pump 15 to repeat the circulation.

The above is the movement of refrigerant and absorption liquid during cooling in an absorption refrigerator.In order to extract hot water during heating, in this example, high-temperature refrigerant vapor is guided from the low-temperature regenerator 5 to the refrigerant reservoir in the condenser 6. The water is bypassed and supplied to the evaporator 4, and the water flowing through the pipes of the evaporator is heated and heated to generate hot water. Since the outside temperature is lower during heating operation than during cooling operation, there is a risk of crystallization of the absorption liquid and freezing of the refrigerant liquid accumulated in the refrigerant reservoir 10 at the bottom of the evaporator 4 when the operation is stopped.

Based on the above requirements, as refrigerant vapor for heating operation,
A branch pipe 18 is provided branching from the pipe leading from the outlet of the low-temperature regenerator 5 to the refrigerant reservoir of the condenser 6, and the high-temperature refrigerant vapor is transferred from the regenerator to the evaporator 4 through this branch pipe, that is, the refrigerant vapor conduit. We are trying to supply it directly. On the other hand, in order to prevent crystallization of the absorption liquid and prevention of freezing of the refrigerant, a branch pipe 20 is branched from the discharge side pipe of the absorption liquid pump 14, and a liquid reservoir 1 at the lower part of the absorber 3 is provided.
A part of the dilute absorption liquid of 1 is transferred to the refrigerant reservoir 1 at the bottom of the evaporator 4.
By guiding the refrigerant to zero, a part of the refrigerant in the refrigerant reservoir 10 overflows and flows into the dilute absorption liquid reservoir 11, thereby preventing the concentration of the dilute absorption liquid from increasing. During heating operation, each branch pipe 18, 20
The valves were opened by operating the cooling/heating switching valves 19 and 21 provided in the air conditioner.

As described above, the conventional heating/cooling switching device requires two heating/cooling switching valves, which not only complicates switching operations but also causes mechanical failures due to erroneous operations.

The present invention eliminates all of the above-mentioned conventional drawbacks, and aims to provide a heating/cooling switching device for an absorption chiller that requires only one touch (one action) to operate and is free from erroneous operation by applying new innovations to the heating/cooling switching device. It is something to do.

The gist of this is that in an absorption refrigerator that extracts hot water during heating from an evaporator through which cold water flows during cooling, a dilute absorption liquid is placed in a liquid reservoir of absorption liquid in a refrigerant vapor conduit that supplies high-temperature refrigerant vapor from a regenerator to an evaporator. By connecting the dilute absorption liquid conduit that supplies the refrigerant reservoir of the evaporator to the refrigerant reservoir of the evaporator via a liquid pumping device, and by providing a cooling/heating switching valve in the refrigerant vapor conduit, it is possible to easily switch between cooling operation and heating operation. A heating/cooling switching device for an absorption refrigerator is characterized by the following.

The present invention will be explained below with reference to embodiments shown in FIGS. 2 and 3. Figure 2 shows a dual-effect absorption refrigerator.
Moreover, FIG. 3 shows a structural system diagram when each of these is applied to a single-effect absorption refrigerator. Components that are the same as those in the conventional FIG.

First, in FIG. 2, the refrigerant vapor evaporated in the high-temperature regenerator 7 is guided through a pipe to the low-temperature regenerator 5, and then to the condenser 6 via a pipe, but a refrigerant vapor pipe branches from the pipe. 28 is provided to supply high temperature refrigerant vapor to the evaporator 4. A liquid pumping device 23 is interposed at a required position of the refrigerant vapor conduit 28, and a dilute absorption liquid conduit 22 from the dilute absorption liquid reservoir 11 is connected to this. As a result, the dilute absorption liquid flowing through the dilute absorption liquid conduit 22 is smoothly transferred from the liquid reservoir 11 to the refrigerant reservoir by the liquid pumping means that utilizes the bubble pump in the liquid pumping device 23 or the injector effect of the refrigerant vapor flowing through the refrigerant vapor conduit 28. It is possible to flow to 10.

In the case of another embodiment shown in FIG. 3, the refrigerant vapor evaporated in the high temperature regenerator 7 is supplied to the evaporator 4 through the refrigerant vapor conduit 38 before flowing into the condenser 6. Other than being different from the embodiment shown in FIG. 2, other parts are the same. Reference numeral 19 in the refrigerant vapor conduit 28 in FIG. 2 and the refrigerant vapor conduit 38 in FIG. 3 is a cooling/heating switching valve.

Next, the effect will be explained.

In the case of the embodiment shown in FIG. 2, first, during cooling operation, the cooling/heating switching valve 19 is kept in a closed state. The circulation of the refrigerant and absorption liquid at this time is the same as in the conventional absorption refrigerator shown in Fig. 1, and the water flowing into the evaporator 4 from the pipe 24 is cooled and taken out as cold water from the pipe 25 for cooling. Served.

Next, during heating operation, the cooling/heating switching valve 19 is kept open.

The refrigerant vapor evaporated and separated in the high-temperature regenerator 7 passes through the pipe line and inside the pipe group of the low-temperature regenerator 5, is guided to the refrigerant vapor pipe 28, bypasses the condenser 6, and enters the refrigerant reservoir 10 in the lower part of the evaporator 4. Supplied nearby. on the other hand,
The dilute absorption liquid flowing into the dilute absorption liquid conduit 22 from the liquid reservoir 11 at the lower part of the absorber 3 connected to the liquid pumping device 23 installed in the refrigerant vapor conduit 28 is entrained with the refrigerant vapor by the liquid pumping means. It is preferably supplied to the refrigerant reservoir 10. This refrigerant vapor is condensed in the evaporator 4, and the latent heat of condensation gives heat to the water flowing in the pipes of the evaporator 4, allowing hot water to be taken out for heating.

Further, a portion of the refrigerant overflows from the refrigerant reservoir 10 and flows into the dilute absorption liquid reservoir 11 to dilute the dilute absorption liquid. This dilute absorption liquid is sent to the high-temperature regenerator 7, where it is concentrated and evaporated into refrigerant vapor, which is repeatedly used as a heating medium for the evaporator 4 through the refrigerant vapor conduit 28. .

In the case of the embodiment shown in FIG. 3, during heating when the cooling/heating switching valve 19 is opened, the refrigerant vapor from the high-temperature regenerator 7 bypasses the condenser 6 and is transferred to the evaporator 4 via the refrigerant vapor conduit 38. The refrigerant is sent to the vicinity of the refrigerant reservoir 10 at the bottom of the
The refrigerant vapor is supplied along with the dilute absorption liquid flowing through the dilute absorption liquid conduit 22 from the dilute absorption liquid reservoir 11 connected to the evaporator 3 by a pumping means such as forming a bubble pump. The condensed refrigerant gives heat to the water flowing in the evaporator tube by the heat of condensation, and the condensed refrigerant accumulates in the refrigerant reservoir 10. In this case, the refrigerant and absorption liquid are circulated in the same manner as in the previous embodiment.

According to the present invention configured as detailed above,
A refrigerant vapor conduit is provided that bypasses the condenser and leads the refrigerant vapor to the evaporator, and the conduit is connected to a dilute absorption liquid conduit from a dilute absorption liquid reservoir via a liquid pumping device, and the refrigerant vapor conduit is connected to the diluted absorption liquid conduit through a liquid pumping device. Since the cooling/heating switching valve is provided, switching between cooling and heating can be performed in one operation, which simplifies the operation, and there is no risk of erroneous operation, and therefore, there is no risk of machine failure due to erroneous operation. Furthermore, since the diluted absorption liquid is guided to the refrigerant reservoir by the pumping means and caused to overflow, this invention is useful in preventing freezing of the refrigerant and crystallization of the absorption liquid, especially during heating operations at low outside temperatures.

[Brief explanation of drawings]

Figure 1 is a structural diagram of a conventional cooling/heating switching device for an absorption refrigerator, Figure 2 is a structural diagram showing an embodiment of the present invention applied to a dual-effect absorption refrigerator, and Figure 3 is a single-effect absorption refrigerator. It is a structural system diagram showing another example applied to a refrigerator. 3...Absorber, 4...Evaporator, 5...Low temperature regenerator, 6...Condenser, 7...High temperature regenerator, 10...
Refrigerant reservoir, 11...liquid reservoir, 22...dilute absorption liquid conduit,
23... Liquid pumping device, 28, 38... Refrigerant vapor conduit.

Claims (1)

[Claims] 1. In an absorption refrigerator that switches between cooling and heating to extract cold water or hot water from the evaporator, dilute absorption liquid is transferred from the absorber's liquid reservoir to the evaporator in the refrigerant vapor conduit that supplies high-temperature refrigerant from the regenerator to the evaporator. The dilute absorption liquid conduit that supplies the refrigerant reservoir is connected via a pumping device, and the refrigerant vapor conduit is provided with a cooling/heating switching valve, thereby making it possible to easily switch between cooling operation and heating operation. Features a heating/cooling switching device for absorption refrigerators.