JP2963566B2 - Absorption type cold / hot water unit - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an absorption type chilled and heated water unit for general air conditioning, and more particularly to an absorption chilled and heated water unit capable of automatic switching operation of cooling and heating and capable of individually distributed air conditioning.

[0002]

2. Description of the Related Art FIG. 5 shows an absorption cooling / heating water unit having an automatic cooling / heating switching function (hereinafter referred to as an absorption cooling / heating water unit).
First, the cooling / heating operation cycle is as follows. During the cooling operation, the cooling / heating switching automatic valves 43 and 44 are closed by the switching operation electric signal. Further, the cooling water system piping 40 is filled with cooling water, with the cooling water system automatic draining valve 48 and the air bleeding automatic valve 49 both closed and the cooling water supply automatic valve 47 opened. By the way, the absorber 30
Solution diluted by the refrigerant (water) with the solution pump 31
Low temperature solution heat exchanger 32, high temperature solution heat exchanger 33
After that, the refrigerant is sent to the high-temperature regenerator 34, where it is heated and the refrigerant is evaporated and concentrated. Further, the low-temperature solution heat exchanger 32
The dilute solution branched from the outlet of the above and sent to the low temperature regenerator 35 exchanges heat with the refrigerant vapor generated from the high temperature regenerator 34 to generate and concentrate the secondary refrigerant vapor. High temperature regenerator 34
The concentrated solution concentrated in is passed through a high-temperature solution heat exchanger 33,
The solution concentrated in the low-temperature regenerator 35 passes through the low-temperature solution heat exchanger 32, and sensible heat is given to the dilute solution by the solution heat exchangers 32 and 33, and then dispersed in the absorber 30. On the other hand, each of the refrigerant vapors generated in the high-temperature regenerator 34 and the low-temperature regenerator 35 is condensed in the low-temperature regenerator 35 and the condenser 36, flows down into the evaporator 37 as a refrigerant liquid. here,
The refrigerant is sprayed into the evaporator by the refrigerant spray pump 38, obtains heat of evaporation from the cold / hot water in the cold / hot water return pipe 4, evaporates, and passes through the vapor passage connecting the evaporator 37 and the absorber 30 to the inside of the absorber. Is absorbed into the concentrated solution. The heat of condensation of the refrigerant generated in the absorber 30 is removed by the cooling water circulating through the cooling water pipe 40. Note that the cooling water circulates through the condenser 36 via the absorber 30 to take away the heat of condensation of the refrigerant vapor generated in the low-temperature regenerator 35,
These condensers are discharged to the outside air and cooled. The cooling water is circulated by the pump 41. In addition, 51 is a Raschig ring.

In the heating operation cycle, the cooling / heating switching automatic valve 4
3, 44 are opened. The automatic water supply valve of the cooling water system is closed, and after the automatic drainage valve 48 is opened to completely drain the cooling water, it is closed. The automatic air bleed valve 49 is closed. Now, the refrigerant vapor generated in the high-temperature regenerator 34 flows into the evaporator 37 via the valve 43 without passing through the low-temperature regenerator 35, and heats the cold / hot water to the cold / hot water return pipe 4 to condense. I do. The condensed refrigerant liquid is sent to the absorber 30 via the cooling / heating switching valve 44 by the refrigerant spray pump 38, where it dilutes the concentrated solution sent from the high temperature regenerator 34 and the low temperature regenerator 35 and sprayed in the absorber. Make a dilute solution and again use solution pump 3
At 1, it is sent to the high temperature regenerator 34 and the low temperature regenerator 35. In this heating cycle, the cooling water circulation pump 41 is stopped, and no heat exchange is performed in the absorber 30 and the condenser 36,
The operation of the cooling tower 42 is also stopped.
The automatic extraction device 45 is for discharging the non-condensable gas in the apparatus kept at the atmospheric pressure or less, and operates continuously or periodically mainly at the time of switching from the heating to the cooling cycle or at the time of the cooling cycle. To prevent a decrease in cooling capacity.

[0004]

When the cooling / heating cycle of such an absorption-type cooling / heating water unit is switched, the cooling water is supplied each time (when switching from the heating to the cooling cycle).
Or drainage (when switching from cooling cycle to heating cycle)
The switching operation requires a long time, and the cycle switching cannot be performed immediately. In addition, when the number of switching of the cycle is increased in the middle period of spring and autumn, there is a disadvantage that the amount of drainage of cooling water increases and water is wasted.

[0005] These drawbacks can be solved by always keeping the cooling water in the path regardless of whether it is cold or warm. However, if the cooling water is always kept in the path, some problems occur. That is, at the time of switching from the heating to the cooling cycle, in the heating operation, the cooling water staying in the absorber and the condenser is heated by the high-temperature refrigerant vapor and becomes high-temperature water. When the cooling water pump is operated, the high-temperature water is extruded as it is and flows down to the cooling tower, and there is a possibility that the plastic-molded Raschig ring 51 or the like in the cooling tower is heated and deformed. This means that the cooling water is frozen in winter.

SUMMARY OF THE INVENTION It is an object of the present invention to solve these problems by enabling constant storage of cooling water, which is a factor of prolonging the cooling / heating switching time and cooling at the time of switching which leads to waste of water. An object of the present invention is to provide an absorption-type cold / hot water system that does not require water supply / drainage.

According to the present invention, a bypass line is connected to a circulation line of cooling water, and an opening / closing control means for the bypass line is provided. The cooling water can be temporarily sent directly into the storage tank by a bypass pipe (claim 1).

The present invention further comprises temperature detecting means for detecting the temperature of the cooling water on the high temperature side, and when the temperature detected by the temperature detecting means is higher than a predetermined value when the operation mode is switched from heating to cooling. It is possible to control so as not to start the cooling operation (claim 2).

Further, the present invention further comprises a temperature detecting means for detecting the temperature of the cooling water on the high temperature side, and performs a heating operation when the detecting means of the temperature detecting means falls below a predetermined value. The control for circulating the cooling water is enabled (claim 3).

Further, according to the present invention, there is provided a water level detecting means for detecting a water level of the cooling water, and when the water level detected by the water level detecting means is equal to or lower than a predetermined value, the cooling water is not circulated. 4).

[0011]

As a treatment of the cooling water at the time of switching the cooling / heating cycle, the cooling water is conventionally drained at the time of heating, but is not drained at all and is kept in the system. At the time of switching from heating to the cooling cycle, high-temperature cooling water retained in the absorber and condensate during heating operation is diverted to the cooling tower by the bypass pipe, and cooling water cooled by outside air is stored. By taking the cooling tower directly into the storage tank, deformation of the cooling tower due to thermal shock is prevented (claim 1). After the high temperature state is eliminated by mixing with the cooling water in the storage tank, the cooling water is returned to the normal circulation state.

Further, according to the present invention, the temperature detecting means for detecting the temperature of the cooling water is provided on the high temperature side of the cooling water, and when the temperature detected by the temperature detecting means is higher than a predetermined value at the time of starting the cooling operation, the cooling operation is started. Is controlled so as not to be performed (claim 2).

Further, in the present invention, in order to prevent the cooling tower and the cooling water pump from being damaged by freezing of the cooling water in winter, a temperature detecting means for detecting the cooling water temperature is provided in the cooling water piping system to detect a decrease in the cooling water temperature. The heating operation and the circulation of the cooling water are performed to prevent freezing of the cooling water (claim 3). Then, in order to protect the cooling water pump, a water level detection level switch is provided in the cooling water piping system to monitor the water of the cooling water, thereby preventing idling due to insufficient water level (claim 4).

[0014]

FIG. 1 shows an embodiment of the present invention.
FIG. 3 shows a control sequence diagram, wherein F1 to F5 are control steps. The same numbers as those in FIG. 5 indicate the same components. Cooling tower 4 in cooling water piping system
2 is supplied by the ball tap valve 50, and the water level of the cooling tower storage tank is controlled so as to be always constant throughout the four seasons. Thus, the cooling water piping system is always maintained in a full state. In addition, the absorber 30, the condenser 3
6 and a bypass pipe 52 of the cooling tower 42 and an automatic valve 5
3 are provided. Then, when switching from the heating to the cooling operation, the automatic valve is opened at the same time when the cooling water pump 41 is operated (F1) (F2), and the cooling water is supplied to the bypass pipe 52.
Flows down to the storage tank 42S of the cooling tower, where it is mixed and cooled. After a certain time (F4),
With the automatic valve 53 closed (F5), the cooling water is passed to the cooling tower 42, and the operation shifts to a normal cooling operation. By performing such control, particularly when the operation is switched to the cooling operation immediately after the heating operation, the absorber 30 and the condenser 3
Since the cooling water in 6 is hot water of about 70 ° C., if this high-temperature water falls on the Raschig ring 51, it may be deformed and impair its function.
This can be avoided.

Another embodiment of the present invention will be described with reference to FIG. FIG. 4 shows a control sequence diagram, and F6 to F9 are control steps. Reference numeral 46 in FIG. 2 denotes temperature detecting means for detecting the temperature of the cooling water, which is disposed in the cooling water piping system. Only when the temperature detected by the temperature detecting means is equal to or lower than the heat-resistant temperature of the cooling tower, control for starting the cooling operation is performed. The location of the cooling water temperature detecting means is not affected by the high temperature side cooling water piping such as the vicinity of the condenser 36 in addition to the high temperature side of the cooling water near the absorber 30 shown in FIG. . The temperature detecting means includes a thermistor and a thermocouple. As a control method, there is an on / off control circuit driven by these output changes.

Next, as a measure for preventing freezing of the cooling water piping system in winter, a cooling water temperature detecting means is provided in a pipe on the low temperature side of the cooling water, thereby performing an antifreezing operation. FIG. 4 shows the control flow. When the cooling water temperature falls below a certain temperature (F6), the heating operation is started (F7). Next, the cooling water pump 41 is operated under the condition that the level switch 55 is turned on (F8) and the cooling water piping system is sufficiently filled with the cooling water (F9). In the heating operation, the cooling water flows down the absorber 30 and the condenser 36, and receives the heat of condensation of the refrigerant vapor as described above. In the prior art, a heating operation for preventing freezing of the cold / hot water piping system 4 is generally performed, but in the present invention, this heating operation is also used for preventing freezing of the cooling water piping system at the same time. Therefore, the control can use the conventional freeze prevention circuit,
Energy can also be saved. As described above, according to the present invention, there is provided an easy-to-use absorption-type cooling / heating water unit that has a short switching time of the heating / cooling cycle and can save water.

[0017]

According to the present invention, it is possible to effectively prevent the cooling tower from being damaged by the high-temperature cooling water at the time of switching from heating to cooling, and to prevent the cooling water from freezing in winter, and to constantly store the cooling water. As a result, since the operation of supplying and draining the cooling water is not required, the time required for switching the cooling / heating cycle is reduced, and an easy-to-use absorption-type cold / hot water unit is provided.

[Brief description of the drawings]

FIG. 1 is a configuration diagram of an absorption-type cold / hot water unit according to an embodiment of the present invention.

FIG. 2 is a configuration diagram of an absorption-type cold / hot water unit according to another embodiment of the present invention.

FIG. 3 is a block diagram illustrating an operation in the embodiment of FIG. 1;

FIG. 4 is a block diagram illustrating an operation in the embodiment of FIG. 2;

FIG. 5 is a configuration diagram of a conventional absorption type cold / hot water unit. DESCRIPTION OF SYMBOLS 41 Cooling pump 42 Cooling tower 43 Cooling / heating switching automatic valve 44 Cooling / heating switching automatic valve 46 Cooling water temperature detecting means 50 Ball tap valve 51 Raschig ring 52 Bypass piping 53 Automatic valve 54 Cooling water temperature detecting means

──────────────────────────────────────────────────続 き Continuation of the front page (56) References Japanese Utility Model Sho 60-154793 (JP, U) Japanese Utility Model Sho 64-13466 (JP, U) Japanese Utility Model Hei 4-8055 (JP, U) Japanese Utility Model Hei 4- 33892 (JP, U) (58) Fields investigated (Int. Cl. ⁶ , DB name) F25B 15/00 306 F25B 15/00

Claims (4)

(57) [Claims] 1. An evaporator for cooling or heating cold and hot water by refrigerant vapor, an absorber containing a solution for absorbing refrigerant vapor in the evaporator, and a cooling water circulation line cooling water for cooling the inside of the absorber. A cooling tower for releasing heat to the outside, and at least a storage tank for storing cooling water passing through the cooling tower, an absorption type with an automatic cooling / heating switching function capable of switching a cooling or heating operation mode by a signal from the outside. In the cooling / heating water unit, a bypass pipe is connected to a circulation pipe of the cooling water, an opening / closing control means for the bypass pipe is provided, and the cooling water is temporarily bypassed when the operation mode is switched from heating to cooling. An absorption-type cold / hot water unit characterized in that it can be sent directly into the storage tank by road. 2. A refrigerant vapor for cooling or heating cold and hot water in an evaporator is absorbed by a solution in an absorber, and a refrigerant vapor is separated from a dilute solution having absorbed the refrigerant vapor in a regenerator. Refrigerant vapor is condensed by a condenser,
This is to be returned to the evaporator again, and the cooling water that has radiated heat in the cooling tower and cooled down is circulated in the absorber and the condenser for cooling,
In an absorption type cooling / heating water unit having an automatic cooling / heating switching function capable of switching a cooling or heating operation mode by an external signal, a temperature detecting means for detecting a temperature on a high temperature side of the cooling water is provided; An absorption type chilled / hot water unit characterized in that it is possible to control so as not to start the cooling operation when the temperature detected by the temperature detecting means at the time of switching from heating to cooling is equal to or higher than a predetermined value. 3. A refrigerant vapor for cooling or heating cold and hot water in an evaporator is absorbed by a solution in the absorber, and the refrigerant vapor is separated in a regenerator from the dilute solution having absorbed the refrigerant vapor. Refrigerant vapor condensed by a condenser,
This is to be returned to the evaporator again, and the cooling water that has radiated heat in the cooling tower and cooled down is circulated in the absorber and the condenser for cooling,
In an absorption type cooling / heating water unit having an automatic cooling / heating switching function capable of switching a cooling or heating operation mode by an external signal, a temperature detecting means for detecting a temperature on a low temperature side of the cooling water is provided; An absorption-type cold / hot water unit, wherein when the detected temperature of the means falls below a predetermined position, a heating operation is performed and control for circulating cooling water is enabled. 4. The cooling water system according to claim 3, wherein a water level detecting means for detecting a water level of the cooling water is provided, and when the water level detected by the water level detecting means is equal to or lower than a predetermined value, the cooling water is not circulated. Absorption type cold / hot water unit.