JP3283780B2 - Absorption cooling device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a cooling apparatus using an absorption refrigeration cycle, and more particularly to a technique for dilution operation when stopping the operation.

[0002]

2. Description of the Related Art As a cooling device using an absorption refrigeration cycle, for example, a technology for cooling a room is known. In the cooling operation, the absorbing liquid is heated to a high temperature (for example, 160 ° C.) by a heating means, a part of the heated absorbing liquid is vaporized by a regenerator, and the vaporized refrigerant is cooled and liquefied by a condenser. The liquefied refrigerant is evaporated under a low pressure by an evaporator, and the heat medium is cooled by cold generated when the liquefied refrigerant evaporates, and the cooled heat medium is guided to the indoor heat exchanger, and the air blown into the room is cooled. The room is cooled by exchanging heat with the heat medium.

When stopping the operation of the absorption refrigeration cycle,
Even if the heating of the absorbent in the regenerator by the heating means is stopped,
Heating of the absorbing solution continues due to the residual heat of the heating means, etc., causing a concentration difference in the absorbing solution in the absorption refrigeration cycle. When the absorbing solution is cooled as it is, crystallization of the high-concentration absorbing solution occurs. If crystallization of the absorbing solution occurs in the absorption refrigeration cycle, the crystallization of the absorbing solution during restarting hinders the circulation of the absorbing solution, and causes a problem that restarting is not possible.

Therefore, conventionally, in order to prevent crystallization of the absorbent, when the operation of the absorption refrigeration cycle is stopped, heating of the absorbent by the heating means is stopped, and a solution pump for circulating the absorbent is operated. The temperature of the absorbing liquid heated by the heating means (for example, the absorbing liquid in the regenerator) is the temperature at which the concentration difference disappears due to circulation (for example, 110
Until the temperature drops to (° C), a dilution operation is performed in which a solution pump for circulating the absorbing solution is operated.

[0005]

When the cooling operation is stopped, there are a high concentration portion and a low concentration portion in the absorption refrigeration cycle. Therefore, only the heating means is stopped and the solution pump is operated. The concentration of the absorbing solution is averaged, and the concentration of the absorbing solution in the regenerator is averaged in a relatively short time, resulting in a short dilution time.

After stopping the operation of the absorption refrigeration cycle,
In some cases, the absorption refrigeration cycle may be restarted within a relatively short time (for example, after the operation is stopped by the user's operation, the operation is restarted again by the user's operation, or when the indoor temperature is set. The operation may be restarted due to a change in the room temperature after the operation has been stopped automatically when the temperature has been reached.)

As described above, when the operation is restarted, the concentration of the absorbent in the regenerator is averaged by the dilution operation even if only a relatively short time has elapsed since the previous operation was stopped. , Because the temperature of the absorbing solution has dropped, it takes time to raise the temperature of the absorbing solution again,
As a result, there was a problem that it took time to restart cooling. Further, since the absorption liquid that has been cooled is both heated again by the dilution operation, wasteful heating energy is required, and the heat energy efficiency is low. Furthermore, the components that make up the regenerator have a retained amount of heat, and the components that make up the regenerator together with the absorbent are cooled by the dilution operation. Will reheat. In other words, unnecessary heating energy is required to reheat the components constituting the regenerator that has been bothersomely cooled together with the absorbing liquid, and this has also led to deterioration in thermal energy efficiency.

[0008]

SUMMARY OF THE INVENTION The present invention has been made in view of the above circumstances, and has as its object to operate an absorption refrigeration cycle in a short time when the operation is restarted within a relatively short time after the operation is stopped. It is an object of the present invention to provide an absorption cooling device which can suppress wasteful heating energy and has high heat energy efficiency.

[0009]

Means for Solving the Problems In order to achieve the above object, the absorption cooling device of the present invention employs the following technical means. (Means of Claim 1) The absorption type cooling device includes: a) a heating means for heating the absorption liquid; and b) a regenerator for vaporizing a part of the absorption liquid heated by the heating means. A condenser that cools and liquefies the vaporized refrigerant, an evaporator that evaporates the liquefied refrigerant liquefied by the condenser under low pressure to cool the heat medium, and an absorber that absorbs the vaporized refrigerant evaporated by the evaporator into an absorbent. An absorption refrigeration cycle including a solution pump for pumping the absorption liquid in the absorber to the regenerator; c) a timer for measuring the passage of time; and d) an environment for detecting the environmental temperature of the absorption refrigeration cycle. E) when an instruction to stop the operation of the absorption refrigeration cycle is given, start the timer, stop the heating of the absorbing solution by the heating means, and stop the operation of the solution pump, Thailand And a dilution operation means for starting the dilution operation by operating the solution pump after a predetermined time has elapsed by the timer, wherein the predetermined time by the timer is set according to the temperature detected by the environmental temperature sensor. It is characterized by the following.

(2) The absorption cooling device according to (1), wherein the dilution operation means stops the operation of the solution pump when an instruction to stop the operation of the absorption refrigeration cycle is given. Instead of the control, the solution pump is operated at a rotation speed lower than the rotation speed during the normal dilution operation to perform the low-speed dilution operation.

[0011]

[0012]

[0013]

When an instruction to stop the operation of the absorption refrigeration cycle is given during the operation of the absorption refrigeration cycle,
The dilution operation means stops the heating of the absorbing solution by the heating means and stops the solution pump (in the invention of claim 2, the solution pump is operated at a rotation speed lower than the rotation speed during the normal dilution operation). As a result, since the dilution of the absorbent in the regenerator does not proceed (or is diluted slowly), the temperature of the absorbent in the regenerator decreases slowly.
Thereafter, when a predetermined time set according to the temperature detected by the environmental temperature sensor elapses, the dilution operation means activates the solution pump (in the invention of claim 2, the solution pump operates at the rotation speed during the normal dilution operation). Then, the dilution liquid is started by circulating the absorption liquid in the absorption refrigeration cycle.

[0014]

As described above, when an operation stop instruction is given to the absorption refrigeration cycle, the heating means and the solution pump are stopped (or operated at a low rotation speed), and the inside of the regenerator is stopped. The temperature of the absorbing solution drops slowly.
For this reason, when the start instruction of the absorption refrigeration cycle is given within a relatively short time after the operation stop instruction of the absorption refrigeration cycle is given, the temperature of the absorbent in the regenerator has not yet dropped so much. Therefore, the absorption-type refrigeration cycle starts up within a short time and exerts its ability.

Further, at the time of such a restart, since the temperature of the absorbent in the regenerator has not decreased so much, the heating energy for reheating the absorbent is small. That is, since the absorption refrigeration cycle can exert its ability with a small amount of heating energy, the heat energy efficiency is improved as compared with the related art. Further, at the time of the restart as described above, since the temperature of the components constituting the regenerator and the like does not drop so much, the heating energy when reheating the components constituting the regenerator and the like is small, and from this result, Also improves thermal energy efficiency. In particular, the effect is great when the amount of heat held by the components constituting the regenerator is large.

[0016]

[Configuration of Reference Example]

In this reference example, an absorption refrigeration system of the present invention is applied to an air conditioner. FIG. 1 is a schematic configuration diagram of an absorption air conditioner that performs indoor air conditioning, and FIG. 2 is a flowchart illustrating control of dilution operation means. 3 is a graph for explaining the operation.

A schematic configuration of the absorption type air conditioner 1 will be described.
In this example, a double effect type was used as an example of the absorption refrigeration cycle 2. The absorption type air conditioner 1 applied to the present embodiment is roughly divided into a double type using a combustion device 3 (corresponding to a heating means of the present invention) for heating an absorbing liquid (a lithium bromide aqueous solution in this embodiment). An effect-type absorption refrigeration cycle 2, an indoor air conditioner 4 for air-conditioning the room with cold / hot water (corresponding to a heat medium of the present invention, water in the present embodiment) cooled or heated by the absorption refrigeration cycle 2, Absorption refrigeration cycle 2
A cooling water cooling means 5 for cooling a cooling water used for cooling and liquefying a vaporized refrigerant (water vapor in this embodiment) in the inside, and a control device 6 for controlling each mounted electric functional component Be composed. The absorption refrigeration cycle 2 using the combustion device 3, the cooling water cooling means 5, and the control device 6
Is installed outdoors as an outdoor unit 7, and an indoor air conditioner 4 is disposed indoors.

(Explanation of Absorption Refrigeration Cycle 2) The combustion apparatus 3 of this embodiment uses a gas combustion apparatus that generates heat by burning gas as a fuel and heats the absorbing liquid by the generated heat. The gas burner 11 includes a gas burner 11 that burns gas, a gas supply unit 12 that supplies gas to the gas burner 11, a combustion fan 13 that supplies air for combustion to the gas burner 11, and the like. And gas burner 1
The boiler 14 of the absorption refrigeration cycle 2 is heated by the heat obtained by the gas combustion of No. 1 to heat the low-concentration absorption liquid (hereinafter, low liquid) supplied into the boiler 14. I have.

The absorption refrigeration cycle 2 includes the above-mentioned boiler 14, and the low liquid supplied into the boiler 14 is heated to vaporize (evaporate) the refrigerant (water) contained in the low liquid. ) By using a high-temperature regenerator 15 to be converted into a medium-concentration absorbing liquid (hereinafter referred to as “medium liquid”), and a pressure difference from the high-temperature regenerator 15 using the heat of condensation of the vaporized refrigerant in the high-temperature regenerator 15. The low-temperature regenerator 16 that heats the supplied middle liquid and vaporizes the refrigerant contained in the middle liquid to turn the middle liquid into a high-concentration absorbing liquid (hereinafter, high liquid), and the high-temperature regenerator 15 and the low-temperature regenerator 16 Condenser 17 that cools and liquefies the vaporized refrigerant (steam)
And an evaporator 18 for evaporating the liquefied refrigerant (water) liquefied in the condenser 17 under a pressure close to vacuum, and an evaporator 18
And an absorber 19 for absorbing the vaporized refrigerant evaporated in the high-temperature liquid obtained by the low-temperature regenerator 16.

(Explanation of the high temperature regenerator 15)
The boiler 14 is disposed in the combustion device 3, and the high-temperature regenerator 15 includes a boiling cylinder 21 extending upward from the boiler 14 in addition to the boiler 14. The vaporized refrigerant that has been boiled in the boiler 14 and the boiling cylinder 21 and vaporized from the low liquid is blown out from the boiling cylinder 21 into the cylindrical high-temperature regeneration container 22. The high-temperature vaporized refrigerant blown into the high-temperature regeneration container 22 is deprived of heat as vaporization heat at the time of evaporating the middle liquid in the low-temperature regenerator 16 through the wall of the high-temperature regeneration container 22, cooled, and cooled. (Water).

In the high-temperature regenerating vessel 22, the medium liquid in the boiling cylinder 21 after the refrigerant in the low liquid is vaporized by being heated by the evaporator 14 and the liquefied refrigerant (water) stored around the heat insulating vessel are insulated. For this purpose, a heat insulating partition tube 24 is provided around the boiling tube 21. The heat insulating partition tube 24 has an upper end joined to the upper end of the boiling tube 21, a lower end provided with a gap from the boiling tube 21, and air for heat insulation between the boiling tube 21 and the heat insulating partition tube 24. Provided to penetrate. The liquefied refrigerant (water) liquefied in the high-temperature regeneration container 22 and separated outside the heat insulating partition tube 24 is guided to the condenser 17 through a liquid refrigerant pipe 25 connected to a lower portion.

(Explanation of the low-temperature regenerator 16)
Includes a cylindrical low-temperature regeneration container 31 covering the high-temperature regeneration container 22. On the other hand, the middle liquid in the boiling cylinder 21 is supplied to the low-temperature regenerator 16 through a middle liquid pipe 26 connected to a lower part of the boiling cylinder 21. The middle liquid pipe 26 is provided with a throttle means 27 such as an orifice. This aperture means 27
When the cooling / heating switching valve 53 described later is closed, the medium flows while maintaining the pressure difference between the high-temperature regenerator 15 and the low-temperature regenerator 16. Do not shed.

In the low-temperature regenerator 16, the middle liquid supplied through the middle liquid pipe 26 is injected toward the ceiling of the high-temperature regeneration container 22. Since the temperature in the low-temperature regeneration container 31 is lower than the temperature of the high-temperature regeneration container 22, the pressure in the low-temperature regeneration container 31 is lower than the pressure in the high-temperature regeneration container 22. Therefore, the middle liquid supplied from the middle liquid pipe 26 into the low-temperature regeneration container 31 is easily evaporated. Then, when the middle liquid is injected into the ceiling of the high temperature regeneration container 22, the middle liquid is heated by the wall of the high temperature regeneration container 22, and a part of the refrigerant contained in the middle liquid evaporates to become a vaporized refrigerant, Becomes high liquid.

The upper part of the low-temperature regeneration vessel 31 communicates with the upper side of the condensing vessel 32 in the shape of an annular vessel through a communicating part 33. Therefore, the vaporized refrigerant evaporated in the low-temperature regeneration container 31 is supplied into the condensation container 32 through the communication portion 33.
On the other hand, the high liquid falls to the lower part of the low temperature regeneration container 31 and is supplied to the absorber 19 through the high liquid pipe 34 connected to the lower part of the low temperature regeneration container 31. A ceiling plate 35 is provided above the low-temperature regeneration container 31, and a gap 36 through which the vaporized refrigerant passes is provided between the outer peripheral end of the ceiling plate 35 and the low-temperature regeneration container 31.

(Explanation of the Condenser 17) The condenser 17 is covered by an annular container-shaped condensing container 32. The condensing container 32 is provided so as to cover the periphery of the upper side of the low-temperature regenerating container 31. Inside the condensing container 32, a condensing heat exchanger 37 for cooling and liquefying the vaporized refrigerant in the condensing container 32 is arranged. ing. The condensing heat exchanger 37 is an annular coil through which cooling water flows. And the low-temperature regenerator 16
The vaporized refrigerant supplied into the condensing container 32 is cooled and liquefied by the condensing heat exchanger 37, and drops below the condensing heat exchanger 37.

On the other hand, a refrigerant is supplied to the lower side of the condensing container 32 from the high-temperature regenerator 15 through the liquid refrigerant pipe 25. When the supplied refrigerant is supplied into the condensing container 32, the pressure difference (the pressure inside the condensing container 32 is about 70 mmHg).
From low pressure), the mixture is reboiled, and supplied in a state where the vaporized refrigerant and the liquefied refrigerant are mixed. Further, a liquid refrigerant supply pipe 38 for guiding the liquefied refrigerant to the evaporator 18 is connected to the condensation container 32. The liquid refrigerant supply pipe 38 is provided with a refrigerant valve 39 for adjusting the supply amount of the liquefied refrigerant supplied from the condensation container 32 to the evaporator 18.

(Explanation of the evaporator 18) The evaporator 18 is provided together with the absorber 19 so as to cover the lower part of the condensing container 32, that is, the lower periphery of the low-temperature regenerating container 31. Evaporation absorption container 41 with annular shape around the periphery
Covered in. An evaporation heat exchanger 42 for evaporating the liquefied refrigerant supplied from the condenser 17 is disposed outside the inside of the evaporation absorption container 41. The evaporating heat exchanger 42 is an annular coil through which cold and hot water (heat medium) supplied to the indoor air conditioner 4 flows. And condenser 1
The liquefied refrigerant supplied from 7 via the liquid refrigerant supply pipe 38 is disposed above the evaporating heat exchanger 42,
It is sprayed onto the evaporating heat exchanger 42 from an annular refrigerant spraying tool 43 having a large number of spraying tubes.

Since the inside of the evaporative absorption container 41 is maintained at a substantially vacuum (for example, 6.5 mmHg), the boiling point is low, and the liquefied refrigerant sprayed to the evaporating heat exchanger 42 is very likely to evaporate. The liquefied refrigerant sprayed on the evaporating heat exchanger 42 evaporates by removing heat of vaporization from the heat medium flowing in the evaporating heat exchanger 42. As a result, the heat medium flowing in the evaporating heat exchanger 42 is cooled. Then, the cooled heat medium is guided to the indoor air conditioner 4 to cool the room.

(Explanation of the Absorber 19) The absorber 19 is covered with the evaporation absorption container 41 as described above. The absorber 19 is provided inside the evaporative absorption container 41 with the high liquid pipe 3.
An absorption heat exchanger 44 for cooling the high liquid supplied from 4 is provided. This absorption heat exchanger 44 is an annular coil,
Inside, cooling water for cooling the high liquid sprayed on the coil is supplied. After passing through the heat exchanger 44 for absorption, the cooling water passes through the heat exchanger 37 for condensation of the condenser 17 and is guided to the cooling water cooling means 5 to be cooled. Then, the cooling water cooled by the cooling water cooling means 5 is guided again to the absorption heat exchanger 44.

On the other hand, on the upper part of the absorption heat exchanger 44, there is arranged an annular absorbent dispersion device 45 for dispersing the high liquid supplied from the high liquid pipe 34 onto the absorption heat exchanger 44. The high liquid sprayed on the absorption heat exchanger 44 is supplied to the absorption heat exchanger 4.
While falling along the coil surface of No. 4 from the upper side to the lower side, the evaporating refrigerant generated by evaporation in the evaporating heat exchanger 42 is absorbed. As a result, the absorption liquid that has fallen to the bottom of the evaporative absorption container 41 becomes a low concentration liquid with a low concentration.

Inside the evaporative absorption container 41, a cylindrical partition wall 4 is provided between the evaporating heat exchanger 42 and the absorbing heat exchanger 44.
6 are arranged. This cylindrical partition wall 46 is used for the evaporator 1.
In order to guide the vaporized refrigerant generated in 8 into the absorber 19,
For example, the upper part is provided with an opening so as to communicate the evaporator 18 and the absorber 19.

A low liquid pipe 47 for supplying the low liquid at the bottom of the evaporative absorption container 41 to the boiler 14 is connected to the bottom of the evaporative absorption container 41. The low liquid pipe 47 is provided with a solution pump 48 for flowing the low liquid from the inside of the evaporation absorption container 41 in a substantially vacuum state toward the boiler 14.

(Description of other components in absorption refrigeration cycle 2) Reference numeral 51 shown in FIG.
A high-temperature heat exchanger 51 for exchanging heat between the medium liquid flowing from inside to the low-temperature regenerator 16 and the low liquid flowing from the absorber 19 to the boiler 14.
a, and a low-temperature heat exchanger 51b for exchanging heat between the high liquid flowing from the low-temperature regenerator 16 to the absorber 19 and the low liquid flowing from the absorber 19 to the boiler 14. The high-temperature heat exchanger 51a cools the middle liquid flowing from the boiling cylinder 21 to the low-temperature regenerator 16 and heats the low liquid flowing from the absorber 19 to the boiler 14. The low-temperature heat exchanger 51b cools the high liquid flowing from the low-temperature regenerator 16 to the absorber 19 and heats the low liquid flowing from the absorber 19 to the boiler 14.

The absorption refrigeration cycle 2 of this embodiment is provided with a heating operation means for performing a heating operation in addition to the cooling operation by the above-described operation. The heating operation means includes a heating pipe 52 for guiding the high-temperature absorbing liquid from the lower part of the boiling cylinder 21 to a lower part of the evaporator 18, and a cooling / heating switching valve 53 for opening and closing the heating pipe 52. The cooling / heating switching valve 53 opens during the heating operation to guide the high-temperature absorbing liquid into the evaporating / absorbing container 41 and heat the cold / hot water flowing in the evaporating heat exchanger 42 of the evaporator 18.

(Explanation of the indoor air conditioner 4)
An indoor heat exchanger 54 for exchanging heat between gas and liquid, forcibly heat-exchanges the cold and hot water passing through the evaporator 18 flowing through the indoor heat exchanger 54 with the room air, and converts the air after the heat exchange into the room An indoor fan 55 for blowing air to the air is provided.

A cold / hot water circuit 56 (corresponding to a heat medium circuit) for circulating cold / hot water is connected to the indoor heat exchanger 54, and a cold / hot water pump 57 for circulating cold / hot water is connected to the cold / hot water circuit 56. Is provided.

The cold / hot water circuit 56 is a water pipe that guides the cold / hot water that has passed through the evaporator 18 to the indoor heat exchanger 54 and guides the cold / hot water that has exchanged heat with the room air to the evaporator 18 again. Inside, the indoor heat exchanger 54 and the cold / hot water pump 57
In addition, a cistern 58 for storing cold / hot water and replenishing cold / hot water in the cold / hot water circuit 56 is provided while functioning as an expansion tank for heating.

A water supply pipe 59 for supplying cold / hot water (tap water) to the inside is connected to the cistern 58. In this water supply pipe 59, supply of cold and hot water into the cistern 58,
A water supply valve 60 for stopping is provided. The cistern 58 includes a water level sensor (not shown).
To open and refill the cistern 58 with cold and hot water. Further, the cistern 58 is provided with overflow water supply means 59a for guiding the overflowed cold / hot water into a cooling water tank 65 described later.

(Description of Cooling Water Cooling Means 5) The cooling water cooling means 5 includes an evaporating cooling tower 61, a cooling water circuit 62 for circulating cooling water, and cooling for circulating and driving the cooling water in the cooling water circuit 62. A water pump 63 is provided. The cooling tower 61 allows the cooling water that has passed through the absorber 19 and the condenser 17 to flow downward from above, exchange heat with the outside air while flowing, and release heat, and partially evaporate while flowing. In this case, heat of vaporization is taken from the cooling water flowing at the time of evaporation to cool the flowing cooling water. The cooling tower 61 includes a cooling water fan 64 that generates an air flow and promotes evaporation and cooling of the cooling water.

The cooling water circuit 62 passes through the absorber 19 and the condenser 17, and supplies the cooling water whose temperature has risen to the cooling tower 61.
The cooling water cooled by the cooling tower 61 is sent to the absorber 19 and the condenser 17 again. In the cooling water circuit 62, the cooling water is supplied to the cooling tower 61 and the cooling water pump 63. Is provided with a cooling water tank 65 for storing the cooling water.

The cooling water tank 65 is installed below the cooling tower 61 and below the cistern 58,
The cooling water passing through 1 is supplied, and the water overflowing in the cistern 58 is supplied. The cooling water tank 65 is provided with a water level sensor (not shown). When the level of the cooling water in the cooling water tank 65 decreases, the water supply valve 60 is opened to overflow the water from the cistern 58, and the overflowed water is supplied to the overflow water supply means 59a.
To the cooling water tank 65 to supply the cooling water.

(Explanation of the control device 6) The control device 6 responds to an operation instruction from a controller (not shown) provided in the indoor air conditioner 4 or an input signal of each of a plurality of sensors provided. Electric functional components such as a valve 39, a solution pump 48, a cooling / heating switching valve 53, a cold / hot water pump 57, a water supply valve 60, a cooling water pump 63, a cooling water fan 64, and electric functional components of the combustion device 3 (the combustion fan 13, the gas It controls the amount control valve 66, the gas on-off valve 67, the ignition device 68, etc.) and controls the indoor fan 55 of the indoor air conditioner 4.

(Explanation of Cooling Operation) When the cooling operation is instructed by the controller of the indoor air conditioner 4, the control device 6 controls the combustion device 3, the cooling water cooling means 5, the solution pump 48, and the cold / hot water pump 57. While operating, the indoor air conditioner 4 instructed to cool turns on the indoor fan 55. In the absorption refrigeration cycle 2, when the combustion device 3 heats the low liquid in the high temperature regenerator 15, the vaporized refrigerant is taken out from the low liquid in the high temperature regenerator 15, and the low temperature regenerator 16 converts the medium refrigerant into the high liquid. The liquid is removed.

The vaporized refrigerant taken out by the high-temperature regenerator 15 and the low-temperature regenerator 16 is condensed and liquefied by the condenser 17 and then dispersed to the evaporator heat exchanger 42 of the evaporator 18 to be evaporated. The heat of vaporization is taken from the cold and hot water in 42 to evaporate. For this reason, the cooled hot and cold water that has passed through the evaporating heat exchanger 42 is supplied to the indoor heat exchanger 54 of the indoor air conditioner 4 via the cold and hot water circuit 56, and exchanges heat with the air blown into the room. It cools the room.

The vaporized refrigerant evaporated in the evaporator 18 flows into the absorber 19. On the other hand, in the absorber 19, the high liquid taken out by the low-temperature regenerator 16 is sprayed to the absorption heat exchanger 44 via the absorbing liquid spraying tool 45, and the high liquid evaporates from the evaporator 18. Coolant is absorbed. Note that the absorption heat generated when the vaporized refrigerant is absorbed by the high liquid is absorbed by the absorption heat exchanger 44, thereby preventing the absorption capacity from lowering. Then, the high liquid that has absorbed the vaporized refrigerant in the absorber 19 becomes a low liquid, is sucked by the solution pump 48, is returned into the boiler 14, and repeats the above cycle.

(Explanation of the operation of the heating operation) When the heating operation is instructed by the controller of the indoor air conditioner 4, the control device 6 operates the combustion device 3, the solution pump 48 and the cold / hot water pump 57, and the cooling / heating switching valve. 53 is opened, and the indoor control unit 6a of the indoor air conditioner 4 to which heating is instructed turns on the indoor fan 55. The combustion device 3 is a high temperature regenerator 15
Is heated, the heated high-temperature absorbing liquid is guided to the lower part of the evaporator 18 through the heating pipe 52,
The cold / hot water flowing in the evaporator heat exchanger 42 of the evaporator 18 is heated. For this reason, the cold and hot water heated by passing through the evaporating heat exchanger 42 is supplied to the indoor air conditioner 4 via the cold and hot water circuit 56.
And heat-exchanges with the air blown into the room to heat the room.

(Explanation of Dilution Operation Control)
An indoor temperature signal of an indoor temperature sensor 70 provided near the air suction port of the indoor air conditioner 4 for detecting the indoor temperature, and a set temperature signal of a temperature setting device (not shown) provided in a controller of the indoor air conditioner 4 And a solution temperature signal of a solution temperature sensor 71 for detecting the temperature of the absorbing solution of the high-temperature regenerator 15 at least. The controller 6 stops the operation of the absorption refrigeration cycle when the room temperature detected by the room temperature sensor 70 reaches the set temperature by the temperature setting device, and when the difference between the room temperature and the set temperature becomes equal to or larger than the predetermined temperature difference ( Alternatively, an indoor temperature control means 6a for restarting the absorption refrigeration cycle 2 when a predetermined time has elapsed is provided.

The control device 6 operates in an absorption type when the operation stop instruction is given to the controller by the user's operation, or when the room temperature reaches the set temperature and the room temperature control means 6a generates the operation stop instruction. A dilution operation means 6b is provided to prevent crystallization of the absorbent in the refrigeration cycle 2. The dilution operation means 6b operates when stopping the operation of the absorption refrigeration cycle 2, and when an operation stop instruction is given, stops the combustion of the combustion device 3 and stops the operation of the solution pump 48. When the temperature of the absorbent in the high-temperature regenerator 15 is the first predetermined temperature (for example, the temperature at which crystallization starts when the temperature of the high
40 ° C., corresponding to the predetermined temperature of the present invention)
The solution pump 48 until the temperature drops to a second predetermined temperature (for example, 110 ° C. at which the absorption liquid in the cycle is homogenized).
Is operated.

The control by the dilution operation means 6b is described in FIG.
This will be described with reference to the flowchart of FIG. When stopping the absorption refrigeration cycle 2 by operating the controller or by operating the indoor temperature control means 6a (start), the combustion of the combustion device 3 is stopped, the operation of the solution pump 48 is stopped, and the indoor fan 55 is stopped. And the operation of the cold / hot water pump 57 is continued (step S1). By continuing the operation of the indoor fan 55 and the cold / hot water pump 57, indoor air conditioning is continued by the amount of heat of the cold / hot water in the cold / hot water circuit 56.

Next, it is determined whether or not the temperature of the absorbing solution in the high-temperature regenerator 15 detected by the solution temperature sensor 71 has dropped to 140 ° C. or lower (step S 2). The result of this judgment
If NO, the process returns to step S2. If the decision result in the step S2 is YES, it is determined that the temperature has decreased to a temperature at which crystallization may occur, and the solution is made uniform (diluted) in the absorption refrigeration cycle 2 in order to make the concentration of the absorption solution uniform. The pump 48 is operated (step S3).

Next, it is determined whether or not the temperature of the absorbing solution in the high-temperature regenerator 15 detected by the solution temperature sensor 71 has dropped to 110 ° C. or less (step S4). The result of this judgment
If NO, the process returns to step S4. If the determination result of step S4 is YES, it is determined that even if the absorption refrigeration cycle 2 is reduced to the outside air temperature, the absorption refrigeration cycle 2 is determined to be diluted by the time the crystallization does not crystallize. The operation is stopped (step S5), and the operation ends (end).

(Operation of Dilution Operation) The operation of the dilution operation means 6b will be described with reference to the graph of FIG. Note that a solid line A indicates a change in the temperature of the absorbing solution due to the operation of the present reference example, and a broken line B indicates the temperature of the absorbing solution in the high-temperature regenerator 15 after the operation stop instruction is given.
5 shows a temperature change of the absorbing solution caused by the operation of the solution pump 48 until the temperature of the absorbent pump decreases to a temperature of 10 ° C.

When an operation stop instruction is given during the operation of the absorption refrigeration cycle 2 (time t 1), the combustion of the combustion device 3 is stopped to stop the heating of the absorbing liquid and the solution pump 4
8 is stopped. In this embodiment, since the solution pump 48 does not operate, the absorption liquid in the absorption refrigeration cycle 2 is not stirred. For this reason, the temperature of the absorbing liquid in the high-temperature regenerator 15 is naturally radiated, and the temperature slowly decreases.

On the other hand, in the prior art, since the solution pump 48 is operated, the absorption liquid in the absorption refrigeration cycle 2 is stirred, and the temperature of the absorption liquid in the high-temperature regenerator 15 is relatively short. Lowers to 110 ° C. For this reason, in the prior art, the temperature of the absorbent in the high-temperature regenerator 15 drops to 110 ° C. in a relatively short time (time t1 to t2) after the operation stop instruction is given.

In the present embodiment, as described above, the temperature of the absorbing liquid in the high-temperature regenerator 15 decreases slowly due to natural heat radiation. Therefore, in this reference example, a relatively long time (time t1)
The temperature of the absorbing solution in the high-temperature regenerator 15 drops to 140 ° C. in the period from t 3). When the temperature of the absorbent in the high-temperature regenerator 15 drops to 140 DEG C. (time t3), the solution pump 48 is operated to stir the absorbent in the absorption refrigeration cycle 2.
For this reason, after the temperature of the absorbent in the high-temperature regenerator 15 has dropped to 140 ° C., the temperature of the absorbent in the high-temperature regenerator 15 drops to 110 ° C. in a relatively short time (time t3 to t4).

(Operation of Restart Operation) After stopping the operation of the absorption refrigeration cycle 2, the absorption refrigeration cycle 2 may be restarted within a relatively short time. An example of the operation in this case will be described based on the graph of FIG. The dashed-dotted line C indicates the temperature change of the absorbing solution due to the reactivation of the present reference example, and the two-dot dashed line D indicates the temperature change of the absorbing solution due to the reactivating of the prior art.

After the operation stop instruction is given to the absorption refrigeration cycle 2 and the start instruction is given to the absorption refrigeration cycle 2 by the operation of the controller or the operation of the room temperature control means 6a (time ta), the absorption refrigeration cycle 2 is stopped. The refrigeration cycle 2 operates, and the combustion device 3 heats the absorbent. In the present reference example, when the start instruction is given, the temperature of the absorbent in the high-temperature regenerator 15 is maintained at a relatively high temperature. Operating temperature (eg, 160 ° C.) in a relatively short time (from ta to tb)
Can be

On the other hand, in the prior art, when a start instruction is given to the absorption refrigeration cycle 2 (at time t).
a) Since the temperature of the absorbent in the high-temperature regenerator 15 has decreased to 110 ° C. or less due to the dilution operation, the temperature of the absorbent in the high-temperature regenerator 15 becomes the operating temperature (for example, after the combustion device 3 is operated). , 160 ° C), it takes a relatively long time (time ta to tc).

[Effects of Reference Example] As shown in the above operation, when the operation stop instruction is given to the absorption refrigeration cycle 2, the heating of the absorbent is stopped by stopping the combustion device 3, Since the dilution operation by the operation of the solution pump 48 is not started until the temperature of the absorbent in the regenerator 15 decreases to 140 ° C., the temperature of the absorbent in the high-temperature regenerator 15 is increased to a high temperature for a relatively long time. Will be maintained. For this reason, after the operation stop instruction is given,
When the start instruction is given within a relatively short time, the absorption refrigeration cycle 2 can be operated within a short time,
Indoor air conditioning can be performed in a short time.

Further, at the time of restart, since the temperature of the absorbing solution in the high-temperature regenerator 15 has not decreased so much, the amount of gas when the absorbing solution is reheated to the operating temperature can be reduced. That is, indoor cooling or heating can be performed with a small amount of gas combustion, so that thermal energy efficiency is improved and energy can be saved. Furthermore, when restarting, the high-temperature regenerator 1
Also, the temperature of the cans constituting the low temperature regenerator 5 and the low temperature regenerator 16 and the like have not dropped so much. Since the can body is made of stainless steel and has a large amount of heat, once it cools it takes time and a large amount of heat to reheat, but when restarting, the temperature of the can body does not drop so much, so the can body is reheated In this case, less heating energy is required, and from this result, the thermal energy efficiency is improved.

[First Embodiment] An embodiment to which the present invention is applied will be described based on the above reference example. In the above-described reference example, an example is described in which the start time of the dilution operation after the operation is stopped is determined by the temperature in the absorption refrigeration cycle 2 (in the reference example, the temperature of the absorbent in the regenerator). In the example, a timer for measuring the passage of time is used to determine the start time of the dilution operation. That is, the controller 6 or the like is provided with a timer for measuring the elapse of a predetermined time, and the dilution operation means 6b is configured to stop the solution pump until a predetermined time elapses from the timer after the operation stop instruction is given to stop the heating means. Is provided.

The higher the environmental temperature in which the absorption refrigeration cycle 2 is installed, the more the temperature is lowered to the absorption liquid crystal deposition temperature.
For this reason, a predetermined time measured by a timer according to a temperature change is set. A specific example will be described. An outside air temperature sensor (an example of an environmental temperature sensor) that detects outside air in which the absorption refrigeration cycle 2 is installed may be provided, and a predetermined time by a timer may be changed according to the temperature detected by the outside air temperature sensor. Further, the predetermined time may be changed by combining the temperature of the absorbing liquid and the environmental temperature.

[Second Embodiment] In the first embodiment combined with the above-described reference example, when the operation of the absorption refrigeration cycle 2 is stopped, the temperature inside the regenerator is set to a predetermined temperature (in the embodiment, the first temperature). The solution pump 48 is stopped until the temperature drops to the predetermined temperature (140 ° C.).
However, in the second embodiment, the solution pump 48 is operated at a low speed (rotation speed lower than the rotation speed in the normal dilution operation) until the temperature in the regenerator decreases to a predetermined temperature after the operation stop instruction, and then slowly. It is provided to perform a dilution operation. With this provision, the temperature of the absorbent in the regenerator after the operation stop instruction is slightly lowered, but the possibility of crystallization can be eliminated.

[Modification] In the first and second embodiments combined with the above-mentioned reference example,
The one-stage dilution type in which the solution pump 48 is stopped (or operated at a low speed) for a certain period of time after the operation stop instruction (the period set by the absorption solution temperature or the timer) and the dilution operation is started after a certain period of time is shown. After the stop instruction, the solution pump 48 is stopped together with the heating means, and the temperature of the absorbing solution is lowered to a certain temperature (for example, 140 ° C.) (or the first
After a lapse of a predetermined time, the solution pump 48 is operated at a low speed to perform a slow dilution operation, and after the temperature of the absorbent decreases to a certain temperature (for example, 125 ° C.) (or after a lapse of the second predetermined time). ), The dilution step may be provided in a plurality of stages, such as performing the dilution operation by operating the solution pump 48 at the normal rotation speed of dilution.

The first and second examples combined with the above reference example
In the embodiment, the double-effect absorption refrigeration cycle 2 is shown as an example of the absorption refrigeration cycle. However, a single-effect absorption refrigeration cycle may be used, or a triple-effect or multiple-effect absorption refrigeration cycle may be used. A refrigerating cycle may be used. In addition, low temperature regenerator 1
Although the example in which the middle liquid is injected into the inside 6 is shown from above the low-temperature regenerator 16, it may be injected from below.

Although the combustion device 3 for burning gas is used as the heating means, another combustion device such as an oil combustion device for burning oil may be used, or the absorption liquid is heated by the exhaust heat of the internal combustion engine. Other heating means such as a heating means and a heating means using an electric heater may be used. The example in which the condensing heat exchanger 37, the evaporating heat exchanger 42, and the absorbing heat exchanger 44 are provided in a coil shape has been described.
Other types of heat exchangers, such as a stacked heat exchanger, may be used.

Although an aqueous solution of lithium bromide has been described as an example of the absorbing solution, other absorbing solutions such as an aqueous ammonia solution using ammonia as a refrigerant and water as an absorbent may be used. As an example of the heat medium, tap water is used and shared with the cooling water in the cooling water circuit. However, other heat medium such as antifreeze or oil different from the cooling water in the cooling water circuit may be used.

The first and second examples combined with the above reference example
In the embodiment, as a means for stopping the dilution operation, when the temperature of the absorbing solution (the temperature of the absorbing solution detected by the solution temperature sensor 71 in the embodiment) decreases to a predetermined temperature (110 ° C. in the embodiment). The example in which the dilution operation was stopped because it was determined that the concentration of the absorbing solution was equalized and the high-concentration portion had disappeared was shown. The dilution operation may be stopped when a required time (for example, 6 to 7 minutes) has elapsed.

The first and second examples combined with the above reference example
In the embodiment, the absorption type air conditioner 1 in which one indoor air conditioner 4 is connected to one outdoor unit 7 is shown. However, the present invention is applied to a multi air conditioner in which a plurality of indoor air conditioners 4 can be connected to one outdoor unit 7. May be applied. When applied to a multi air conditioner, the operation of the absorption refrigeration cycle 2 is stopped when all the indoor air conditioners 4 are stopped, and any one of the indoor air conditioners 4 is stopped.
Is activated to start the absorption refrigeration cycle 2. For this reason, in the multi-air conditioner, the ratio at which the start instruction is given within a relatively short time after the operation is stopped increases, and the frequency of implementing the present invention increases. That is, the rate of restarting in a short time is increased, and the thermal energy efficiency is further improved.

[Brief description of the drawings]

FIG. 1 is a schematic configuration diagram of an absorption type air conditioner.

FIG. 2 is a flowchart illustrating control of a dilution operation unit.

FIG. 3 is a graph showing temperature change with time.

[Explanation of symbols]

 REFERENCE SIGNS LIST 1 Absorption air conditioner 2 Absorption refrigeration cycle 3 Combustion device (heating means) 4 Indoor air conditioner 6 Controller 6a Indoor temperature control means 6b Dilution operation means 15 High temperature regenerator 16 Low temperature regenerator 17 Condenser 18 Evaporator 19 Absorber 48 Solution pump 70 Room temperature sensor 71 Solution temperature sensor

Continuation of the front page (56) References JP-A-60-71867 (JP, A) JP-A-4-340066 (JP, A) JP-A-1-123960 (JP, A) JP-A-2-161264 (JP) , A) (58) Fields investigated (Int. Cl. ⁷ , DB name) F25B 15/00 306

Claims (2)

(57) [Claims] 1. A heating means for heating an absorbing liquid ; and b) a part of the absorbing liquid heated by the heating means is vaporized.
Regenerator, which cools the vaporized refrigerant generated by this regenerator
To reduce the pressure of the liquefied refrigerant liquefied by this condenser.
Evaporator that cools the heating medium by evaporation
Absorber that absorbs the generated vaporized refrigerant into the absorbing liquid.
Equipped with a solution pump for pumping the absorbent in the vessel to the regenerator
An absorption refrigeration cycle, c) a timer for measuring the passage of time, and d) an environment for detecting the environmental temperature of the absorption refrigeration cycle.
A temperature sensor, e) operation stop command of the absorption refrigerating cycle is given
When the timer is started, the heating
Of heating of absorbing solution by means and operation of the solution pump
Stop, and after the elapse of the predetermined time by the timer,
Dilution operation to start the dilution operation by operating the solution pump
And means, wherein the predetermined time by the timer, the environmental temperature sensor
An absorption type cooling device, which is set according to a temperature detected by the cooling device. 2. The absorption cooling apparatus according to claim 1, wherein said dilution operation means stops the operation of said absorption refrigeration cycle.
Stop operation of the solution pump when a stop instruction is given
The solution pump is rotated at a speed lower than the rotation speed during the normal dilution operation.
An absorption-type cooling device, which operates at a rotation speed to perform a low-speed dilution operation .