JPH04148162A - Absorption refrigerating machine - Google Patents

Abstract

PURPOSE:To prevent water hammer at the time of starting by providing a valve unit to be closed after an operation is stopped at least at one or both of a lowest position at the feeding side of an evaporator of a heat transfer medium feed tube and in the vicinity of the evaporator at the inlet side of the evaporator. CONSTITUTION:A flowout preventive solenoid valve 21 is disposed at the discharge side of a lowermost position of a heat transfer medium pump 19 near an evaporator 1. The pump 19 is stopped immediately after its operation is stopped, and a heat transfer medium supply tube 17 is blocked simultaneously or substantially simultaneously. The supply tube 17 is opened simultaneously or substantially simultaneously upon starting of the pump 19 immediately after the operation is started. In a room cooling operation of a room, heat transfer medium from a fan coil unit 12 is introduced into the evaporator 1 through a heat transfer medium inlet tube 18, and heat transfer medium cooled by the vaporization heat of the refrigerant in a cooling heat transfer unit 13 is supplied from the tube 17 into the unit 12. Since the valve 21 is closed after a cooler is stopped, reverse flows of the medium in the unit 12, the tubes 17, 18 from the tube 17 into the evaporator 1 are prevented, and generation of vapor space in the unit 12, the tubes 17, 18 can be prevented to eliminate water hammer at the time of starting.

Description

DETAILED DESCRIPTION OF THE INVENTION FIELD OF INDUSTRIAL APPLICATION The present invention particularly relates to an absorption refrigerator which can prevent water hammer during startup.

BACKGROUND ART There is an absorption type air conditioning system that sends refrigerant directly to a heat exchanger (fan coil unit) installed indoors. This absorption refrigerator uses a flash evaporator that flash-evaporates a refrigerant (for example, water) and drops a heat transfer medium to cool the refrigerant using the heat of vaporization of the refrigerant. For example, an absorber that absorbs lithium bromide (aqueous solution of lithium bromide), a regenerator that absorbs refrigerant vapor in this absorber and heats the diluted absorption liquid, and a regenerator that heats the diluted absorption liquid that is heated in this regenerator and separated from the liquid. A condenser condenses the refrigerant vapor, a concentrated absorption liquid transfer pipe that sends the concentrated absorption liquid that has been separated from the refrigerant vapor in the regenerator to the absorber, and a solution pump in the middle to reduce the concentration of the refrigerant vapor in the absorber. It consists of a dilute absorption liquid transfer pipe that sends the diluted absorption liquid to the regenerator. In this configuration, the indoor cooling operation is performed using the refrigerant evaporation Q
A refrigeration cycle of absorption φ regeneration Q condensation is performed, and the heat transfer medium on the indoor heat exchanger side is guided into the evaporator and cooled.

Problems to be Solved by the Invention According to the above configuration, during shutdown, the heat transfer medium in the heat transfer medium transfer pipe and the indoor heat exchanger (fan coil unit) flows out due to the height difference between the evaporator and the indoor heat exchanger. If a vapor space is created, water hammer will occur during startup,
The shock may cause leakage within the system or cause anxiety to the user. Additionally, if the heat transfer medium is discharged from the fan coil unit or heat transfer medium transfer pipe located in a high position to the evaporator after the operation is stopped, it may enter the absorption liquid from the evaporator through the diluted absorption liquid transfer pipe. This will dilute the absorbent solution excessively, and it will take a long time for the cooling function to take effect when restarted.

SUMMARY OF THE INVENTION An object of the present invention is to solve the above-mentioned problems and provide an absorption refrigerator that can prevent water hammer from occurring during startup and prevent the absorption liquid from becoming excessively diluted.

Means for Solving the Problems In order to solve the above problems, we have developed a flash-type evaporator that flash-evaporates the refrigerant and drips a heat transfer medium to cool the refrigerant using the heat of vaporization of the refrigerant. an absorber that absorbs the refrigerant vapor into an absorption liquid; a regenerator that absorbs the refrigerant vapor in this absorber and heats the diluted absorption liquid; a condenser for condensing the refrigerant vapor, a concentrated absorption liquid transfer pipe for sending the concentrated absorption liquid obtained by separating the refrigerant vapor in the regenerator to the absorber, and regenerating the diluted absorption liquid in the absorber. An absorption refrigerating machine equipped with a dilute absorption liquid transfer pipe for sending the diluted absorption liquid to the evaporator, and a heat transfer medium transfer pipe for circulating and transferring the heat transfer medium between the evaporator and a heat exchanger placed indoors, The first means is to provide a valve device that is closed after the operation is stopped at the lowest position of the heat transfer medium transfer pipe on the sending side of the evaporator and at least one or both near the evaporator on the introduction side to the evaporator. It is something.

In the second method, a liquid sealing U-shaped tube is provided at the highest position on the introduction side of the heat transfer medium transfer tube to the evaporator.

According to the first means, after the operation is stopped, the valve device is closed on at least one side of the heat transfer medium transfer pipe on the evaporator side, thereby preventing the heat transfer medium from flowing into the evaporator from the heat transfer medium transfer pipe. Therefore, it is possible to prevent a vapor space from forming in the heat transfer medium transfer pipe, prevent water hammer from occurring at startup, and also prevent dilution of the absorption liquid.

In addition, the second means (according to which, after the operation is stopped, a U provided at the highest position on the introduction side from the indoor heat exchanger to the evaporator)
The double tube prevents the heat transfer medium from flowing out from the heat transfer medium transfer tube to the evaporator, thereby preventing the formation of a vapor space in the heat transfer medium transfer tube and preventing water hammer from occurring during startup. It is possible to prevent this and also to prevent dilution of the absorption liquid.

EXAMPLE A first example of an absorption refrigerator according to the present invention will be described below with reference to FIG.

The absorption refrigerator in this embodiment uses a refrigerant (for example, water)
A flash section 11 for flash evaporation of the refrigerant is arranged, and a heat transfer medium (for example, water) is dropped from the top to cool it by the heat of vaporization of the refrigerant and send it to the fan coil unit (heat exchanger) 12 installed indoors. Heat transfer part I3
an evaporator 1 in which the refrigerant vapor evaporated in the evaporator 1 is introduced through a communication part (for example, a communication pipe) and absorbed into an absorption liquid (for example, a lithium bromide aqueous solution).
, a regenerator 3 that absorbs refrigerant vapor in the absorber 2 and heats the diluted absorption liquid, and a gas that is heated in the regenerator 3 to separate the refrigerant vapor from the gas-liquid mixed liquid. A liquid separator 4, a condenser 5 for condensing the refrigerant vapor separated by the gas-liquid separator 4, and an absorber for separating the refrigerant vapor and converting the concentrated absorption liquid into an absorber. 2, a dilute absorption liquid transfer pipe 16 having a solution pump 15 on the way and sending the diluted absorption liquid from the absorber 2 to the regenerator 3, The cooling heat transfer unit I is connected between the cooling heat transfer unit 13 and the fan coil unit 12.
The heat transfer medium cooled in step 3 is transferred to a fan coil unit (heat exchanger) 12 installed indoors by a heat transfer medium pump 19.
a heat transfer medium supply pipe (heat transfer medium transfer pipe) 17 for feeding the heat transfer medium into the cooling heat transfer section 13 of the evaporator 1; (medium transfer pipe) 18.

In this first embodiment, an outflow prevention electromagnetic valve (an example of a valve device) 21 is interposed at the lowest position on the discharge side of the heat transfer medium pump 19 near the evaporator l of the heat transfer medium supply pipe 17,
The refrigerator control device (not shown) closes the heat transfer medium supply pipe 17 at the same time or before or after the heat transfer medium pump 19 stops immediately after the operation stops, and also starts the heat transfer medium pump 19 immediately after the operation starts. The heat transfer medium supply pipe 17 is opened at the same time or before or after.

In the above configuration, the indoor cooling operation is performed by performing the refrigeration cycle of evaporation φ absorption φ regeneration condensation of the refrigerant as in the conventional case, and also by introducing the heat transfer medium from the fan coil unit 12 through the heat transfer medium introduction pipe 18. A heat transfer medium that has been guided into the evaporator 1 and cooled by the heat of vaporization of the refrigerant in the cooling heat transfer section I3 is supplied to the fan coil unit 12 from a heat transfer medium supply pipe 17.

According to the above configuration, since the solenoid valve 21 is closed after the cooling machine is stopped, the heat transfer medium in the fan coil unit 12 and the heat transfer medium pipe lines 17 and 18 flows from the heat transfer medium supply pipe 17 into the evaporator 1. Backflow is prevented, and vapor spaces can be prevented from forming within the fan coil unit 12 and the heat transfer medium pipes 17 and 18.

Therefore, water hammer does not occur during startup, and the absorption liquid is not diluted.

FIG. 2 shows a second embodiment, in which, in addition to the electromagnetic valve 21 of the first embodiment, the heat transfer medium introduction pipe 18 is also connected near the evaporator 1 immediately after the operation is stopped. A solenoid valve 31 is interposed to close the heat transfer medium inlet pipe 18 and open the heat transfer medium introduction pipe 18 immediately after the start of operation.

According to the second embodiment, in addition to the effects of the first embodiment, it is possible to prevent the heat transfer medium from flowing into the evaporator l due to the height difference between the fan coil unit h12 and the heat transfer medium introduction pipe 18, Fan coil unit I2 and heat transfer medium pipe line 17
．． It is possible to further reliably prevent the formation of a vapor space within 18. Therefore, water hammer does not occur during startup, and the absorption liquid is not diluted.

Note that in the second embodiment, only the solenoid valve 31 may be used.

FIG. 3 shows a third embodiment, in which a solenoid valve 3 of the second embodiment is shown.
1, a U-shaped pipe 41 for liquid sealing is interposed at the uppermost position near the evaporator l. According to this configuration, after the refrigerator is stopped, the U-shaped tube 41 at the uppermost position of the heat transfer medium introduction pipe 18 prevents the heat transfer medium from flowing toward the evaporator 1 side, and the fan coil unit 12 and heat transfer Media line 1
7.18 can be prevented from forming a vapor space. Therefore, water hammer does not occur during startup, and the absorption liquid is not diluted.

Effects of the Invention As described above, according to the first means of the present invention, after the operation is stopped, the valve device is closed at least on the evaporator side of the heat transfer medium transfer pipe, and the heat transfer medium is transferred to the heat transfer medium transfer pipe. Since it is prevented from flowing into the evaporator, it is possible to prevent a vapor space from forming in the heat transfer medium transfer pipe, and it is possible to prevent water hammer from occurring at startup, and also to prevent dilution of the absorption liquid.

Further, according to the second means, after the operation is stopped, the heat transfer medium is transferred from the heat transfer medium transfer pipe by the U-shaped tube provided at the highest position on the introduction side from the indoor heat exchanger to the cooling heat transfer section. Since it is prevented from flowing out to the evaporator side, it is possible to prevent a vapor space from forming in the heat transfer medium transfer pipe, and it is possible to prevent water hammer from occurring at startup, and also to prevent dilution of the absorption liquid.

[Brief explanation of drawings]

FIG. 1 is a block diagram showing a first embodiment of an absorption chiller according to the present invention, FIG. 2 is a block diagram showing a second embodiment, and FIG. 3 is a block diagram showing a third embodiment. be. DESCRIPTION OF SYMBOLS 1... Evaporator, 2... Absorber, liquid separator, 5... Condenser, 11 2... Fan coil unit, 14... Concentrated absorption liquid transfer pipe, l6 17... Transmission Heat medium supply pipe, 18 19... Heat transfer medium pump, 21 1... U-shaped tube. 3...Regenerator, 4...Air...Flash section, 1 13...Heat transfer section for cooling,...Dilute absorption liquid transfer pipe,...Heat transfer medium introduction pipe 1. 31... retaining valve, 4

Claims (1)

[Claims] 1. A flash type evaporator that flash-evaporates the refrigerant and drops a heat transfer medium to cool the refrigerant using the heat of vaporization of the refrigerant, and an absorption system that absorbs the refrigerant vapor evaporated by the evaporator into an absorption liquid. a regenerator that absorbs refrigerant vapor in the absorber and heats the diluted absorption liquid; a condenser that condenses the refrigerant vapor that has been heated in the regenerator and separated from the liquid; a concentrated absorption liquid transfer pipe that sends the concentrated absorption liquid that has been separated from the refrigerant vapor in the regenerator to the absorber; and a dilute absorption liquid transfer pipe that sends the diluted absorption liquid that has become diluted in the absorber to the regenerator;
In an absorption refrigerator equipped with a heat transfer medium transfer pipe that circulates and transfers a heat transfer medium between the evaporator and a heat exchanger arranged indoors, the minimum 1. An absorption refrigerating machine, characterized in that a valve device that is closed after the operation is stopped is provided in at least one or both of the position near the evaporator and the introduction side to the evaporator. 2. A flash type evaporator that flash-evaporates the refrigerant and drips a heat transfer medium to cool the refrigerant using the heat of vaporization of the refrigerant, an absorber that absorbs the refrigerant vapor evaporated by this evaporator into an absorption liquid, and this absorber. a regenerator that absorbs refrigerant vapor and heats the diluted absorption liquid, a condenser that condenses the refrigerant vapor that has been heated by the regenerator and separated from the liquid; a concentrated absorption liquid transfer pipe that sends the separated and concentrated concentrated absorption liquid to the absorber; a dilute absorption liquid transfer pipe that sends the diluted absorption liquid that has become diluted in the absorber to the regenerator;
In an absorption refrigerator equipped with a heat transfer medium transfer pipe that circulates and transfers a heat transfer medium between the evaporator and a heat exchanger arranged indoors, on the introduction side of the heat transfer medium transfer pipe to the evaporator. An absorption refrigerator characterized by having a U-shaped tube for liquid sealing at the highest position.