JPH0399138A - Heat exchangers and air conditioner - Google Patents

Abstract

PURPOSE:To miniaturize further an air conditioner by installing a circuit for cold water including the first, second headers and the first tubes and a circuit for cold water or hot water including the third, fourth headers and the second tubes. CONSTITUTION:By supplying the cold water from cold water piping to the first and second headers 28a, 28b the space cooling capacity determined by the numbers of steps and rows in the first tubes 32 is exhibited. By supplying cold water or hot water to the third and fourth headers 30a, 30b the space cooling or heating capacity determined by the numbers of steps and rows in the second tubes 54, 56 is exhibited. In an air conditioner a heat exchanger 14 can be brought into space cooling operation by supplying cold water to the cold water piping and into space heating operation by supplying hot water to the cold and not water piping at the winter season. By supplying cold water to the cold water piping and the cold and hot water piping together the exchanger 14 is brought into space cooling operation at the summer time.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to heat exchangers and air conditioners, and in particular to so-called four-pipe air conditioners in which heating or cooling operation can be individually controlled for each air conditioner. This invention relates to a harmonizing device and a heat exchanger used therein.

[Prior art]

In the conventional four-pipe air conditioner shown in FIG. 7, each air conditioner 1 includes a cooling heat exchanger 2 and a heating heat exchanger 3. Chilled water from a cold heat source 4 is supplied to the cooling heat exchanger 2 of each air conditioning Ja1 from a cold water pipe 6 by a cold water pump 5, and to the heating heat exchanger 3 by a hot water pump 8 from a hot heat source 7. Hot water is supplied from hot water piping 9.

In the conventional air conditioner shown in FIG. 7, by controlling the control valves provided in relation to each air conditioner 1, each air conditioner can be operated for heating or cooling.

[Problems to be Solved by the Invention] However, the conventional air conditioner shown in FIG. 7 has the following problems. That is, each air conditioner 1
It is necessary to provide a cooling heat exchanger 2 and a heating heat exchanger 3 for each type of air conditioner, which increases the size of the air conditioner. In addition, generally in this type of air conditioner,
The maximum load amount is determined by the energy required for air conditioning operation in the summer. That is, the capacity of the cold water pump 5 and the cold water piping 6 is required to sufficiently handle the maximum load amount. Therefore, if the maximum load amount is considered, their capacity must necessarily be increased. Furthermore, hot water is not supplied from the heat source 7 to the hot water pipe 9 during the summer, and water is not passed through the hot water pipe 9 during the summer. Therefore, the water in the hot water pipe 9 is likely to rot, and foreign matter is likely to accumulate in the hot water pipe 9.

Therefore, the main object of the present invention is to provide a heat exchanger and an air conditioner that can make the air conditioner more compact.

Another object of the present invention is to provide an air conditioner that can further reduce the capacity of a cold water pump and cold water piping.

Another object of the present invention is to provide an air conditioner that can reduce as much as possible the spoilage of water in the pipes or the accumulation of foreign matter in the pipes.

[Means to solve the problem]

Simply put, the first invention includes a first tube connected between the first and second headers and the first and second headers, and having a first predetermined number of stages and a first predetermined number of rows. and a third and fourth header and a second tube connected between the third and fourth headers and having a second predetermined number of stages and a second predetermined number of rows. Alternatively, it is a heat exchanger equipped with a hot water circuit.

Simply put, the second invention provides an air conditioner including a heat exchanger having both a cold water circuit and a cold water or hot water circuit, a cold heat source, and a cold water source that supplies cold water to the cold water circuit of the heat exchanger. Cold water piping, hot and hot water sources, cold and hot water piping that supplies cold or hot water from the cold or hot water source to the cold or hot water circuit of the heat exchanger, and hot and cold water piping that supplies cold water from the cold or hot water source to This is an air conditioner equipped with a switching means for switching whether hot water is supplied.

[Effect]

In the heat exchanger, by supplying cold water from the cold water piping to the first and second headers, the cooling capacity determined by the number of stages and the number of rows (the number of buses) of the first tubes is exhibited. Furthermore, by supplying cold water and hot water to the third and fourth headers, the cooling capacity or heating capacity determined by the number of stages and rows (number of buses) of the second tubes is exhibited.

In an air conditioner, an air conditioner, that is, a heat exchanger, performs cooling operation by supplying cold water to a cold water pipe in the winter. In addition, heating operation is possible by supplying hot water to the cold and hot water pipes during the winter. In the summer, the air conditioner, ie, the heat exchanger, is operated for cooling by supplying cold water to both the cold water piping and the cold/hot water piping.

[Effect of the invention] According to this invention, since the heat exchanger is equipped with both a cold water circuit and a cold water or hot water circuit, only one heat exchanger is provided in each air conditioner, which is the same as the conventional four-pipe system. It is possible to operate in such driving modes. Therefore, the air conditioner can be made more compact than the conventional air conditioner which is provided with two heat exchangers.

In addition, in general, in this type of air conditioner, the cooling load in summer is greater than the heating load, and the maximum amount of cold water is about twice the maximum amount of hot water, but according to the present invention,
By supplying cold water to both the cold water pipe and the cold/hot water pipe, the capacity of the cold water pump and the cold water pipe can be reduced accordingly.

That is, in the conventional air conditioner shown in FIG. 7, the capacity of the cold water pump and cold water piping must be made large enough to handle the maximum amount of cold water, but according to the present invention, cold water can be added to the cold and hot water piping as needed. By supplying water, the capacity of cold water pumps, etc. can be reduced by that amount.

Further, according to the present invention, either cold water or hot water is supplied to the hot and cold water pipes, so that spoilage of water and accumulation of foreign matter in the pipes due to water not being supplied to the pipes is minimized.

The above objectives and other objectives of this invention. Features and advantages will become more apparent from the following detailed description of the embodiments with reference to the drawings.

(Example) Referring to FIGS. IA and IB, an air conditioner 10 of this example includes air conditioners 12A, 12B, etc. provided in each individual air conditioning area or room. Each of the air conditioners 12A, 12B, . Therefore, in each air conditioner 12A, 12B, . It is discharged into the room from the outlet 22. Therefore, when the cold water is supplied to the heat exchanger 14 from the cold water pipe 24, the air conditioner 12 is operated for cooling.
When cold water is supplied to the heat exchanger l4 from 6, cooling operation is performed, and when hot water is supplied, heating operation is performed.

Each air conditioner 12A, 1 shown in Figure IA and Figure IB
The heat exchanger 14 used for 2B, . . . is, for example,
It is constructed as shown in FIG. In FIG. 2, the heat exchanger 14 includes first and second headers 28a and 28b for cold water and third and fourth headers for cold or hot water.
headers 30a and 30b. left header 2
8a and 30a are configured as population headers, respectively, and right-hand headers 28b and 30b are configured as exit headers. Between the artificial header 28a for cold water and the outlet header 28'b, there are 8 rows of 3 tubes 32 with a pass number (number of times the heat transfer fluid goes back and forth between the headers) of 8.
Connected in stages. Similarly, between the inlet header 30a and the outlet header 30b for cold water or hot water, three stages of tubes (same as the above-mentioned tubes 32) with a path number of "8" and eight rows are connected.

And the first and second headers 28a of the heat exchanger 14
and 28b are connected to the cold water pipe 24 described above to form a closed loop. Similarly, the third and fourth headers 30a and 30b are
It is connected to the cold and hot water pipe 26 so as to form a closed loop.

A cold heat source 34 is connected to the cold water pipe 24, and a cold water pump 36 is provided downstream of the cold heat source 34. on the other hand,
The heat source 38 is included in the cold/hot water pipe 26, and the above-mentioned cold/heat source 34 is further connected to the cold/hot water pipe 26. A cold/hot water pump 40 is inserted downstream of the heat source 38 (cold heat source 34). A control valve 42 is interposed between the cold/hot water pump 40 and the cold/hot water pump 40, and a control valve 44 is connected between the heat source 38 and the connection point between the cold/hot water pump 40 and the control valve 42.

In addition, each air conditioner 12A, 1 in the cold water pipe 24
Cold water outlet header 28b of heat exchanger 14 of 2B,...
Control valves 46A and 46B are provided on the downstream side of (Fig. 2), respectively.
,... are connected. In the cold/hot water piping 26, control valves 48A, 48B, . . . are provided downstream of the cold water or hot water outlet headers 30b (FIG. 2) of the heat exchangers 14 of the air conditioners 12A, 12B, .・is connected. The control valve 4 is further connected to a cold source 34 or a hot source 38 via a control valve 50 or 52. In addition,
There is no substantial problem even if the control valves 50 and 52 are not provided.

In this way, the cold water piping 24 is connected to cold or hot water. Heat exchanger 1 of JfA34 and each air conditioner 12A, 12B, ...
4 cold water circuit (inlet header 28a and outlet header 28
b) and the tubes connected therebetween), the cold and hot water piping 26 connects to the cold heat source 34 or the hot heat source 38 and the heat exchanger 14 of each air conditioner 12A, 12B,...
hot and cold water circuit (population header 30a and outlet header 30
b and the tubes connected between them) to form a cold/hot water (chilled or hot water) system. At this time, the control valve 42,
44, 50 and 52 act as switching means for cold water or hot water, ie cold source 34 or hot source 36.

Figure IA shows an example of winter operation, with the upper air conditioner 1
Consider a case where the air conditioner 2A is in heating operation and the lower air conditioner 12B is in cooling operation.

In this case, control valves 44 and 52 are opened and control valve 42
and 50 are closed. Hot water from the heat source 38 is supplied to the cold and hot water headers 30a and 30b (FIG. 2) of the air conditioner 12A. For that purpose, the control valve 46A
is closed, and control valve 48A is opened (controlled). However, since the lower air conditioner 12B performs cooling operation, the cold water is transferred to the first and second headers 28a and 28b.
(Figure 2). For this purpose, control valve 48B is closed and control valve 46B is opened (controlled).
Ru.

In this way, the heat exchanger 1 of the upper air conditioner 12A
Since the hot water circuit No. 4 is supplied with hot water from the heat source 38, the upper air conditioner 12A is operated for heating. On the other hand, the cold water circuit of the heat exchanger l4 of the lower air conditioner 12B is supplied with cold water from the cold heat source 34, so that the lower air conditioner 12 is operated for cooling.

Note that since this is a winter cooling operation, in this embodiment, cold water is supplied only to the cold water circuit of the heat exchanger l4 of the lower air conditioner 12B.
4, cooling operation will be performed with about half the heat exchange capacity. However, the cooling load in winter is not so large compared to that in summer, and generally the heat exchanger 14 shown in FIG. 2 can adequately handle the load. The case where the cooling load and heating load in winter are significantly different will be described later.

Next, consider the summer operation shown in FIG. IB, in which both air conditioners 12 are operated for cooling.

In this case, control valves 42 and 50 are opened and control valve 44
and 52 are closed. Therefore, hot water from the heat source 38 is not supplied to the heat exchanger 14 of any air conditioner [12A, 12B, . . . In addition, the control valve 46A.
48A, 46B and 48B are opened (controlled).

Therefore, the cold/hot water pump 40 functions as a cold water pump, and the heat exchanger 1 of each air conditioner 12A, 12B, .
Cold water from a cold heat source 34 is supplied to both the cold water circuit No. 4 and the cold/hot water circuit. Therefore, in this case, each of the air conditioners 12A, 12B, . . . is operated at its maximum capacity.

In this way, since the heat exchanger 14 of each air conditioner 12A, 12B, . By supplying cold water to the cold water circuit, and supplying hot water to the cold/hot water circuit for other air conditioners, the individual air conditioners 12A, 12B, . . . can be operated for either cooling or heating. . Furthermore, in the summer, cold water is allowed to flow through both the cold water circuit and the cold/hot water circuit of the heat exchanger 14, allowing all the air conditioners 12A, 12B, . . . to operate at their maximum capacity.

In summer operation, the control valves 48A and 48B of the chilled water circuit of each heat exchanger are adjusted according to the cooling load as necessary.
,... are fully opened, then the control valve 46A of the cold/hot water circuit is opened.
, 46B, . . . can be opened, improving controllability.

Furthermore, the above-mentioned heat exchanger 14 used in each air conditioner 12A, 12B, . . .
It may also be modified as shown in the figure.

The heat exchanger 14 shown in FIG.
The tube 54 with the number of passes of "4" is connected to the headers 28a and 28b of. On the other hand, tubes 56 having the same number of buses are connected between the third and fourth headers 30a and 30b for cold water or hot water. However, in the embodiment shown in FIG. 3, unlike the embodiment shown in FIG.
It is 6j. The example in FIG. 3 is effective when a larger amount of water is required than in FIG. 2.

In both of the embodiments shown in FIGS. 2 and 3, the total number of tube passes constituting the cold water circuit is the same as the total number of tube passes constituting the cold/hot water circuit. That is, 50% of the exchange capacity of the heat exchanger 14 was distributed to the cold water circuit and the cold/hot water circuit, respectively. However, such proportions can be changed arbitrarily.

That is, in the heat exchanger 14 of the embodiment shown in FIG. 4, the embodiment shown in FIG.
Tubes with the same number of passes were installed in two stages between a and 30b. Therefore, in the case of this embodiment, the exchange capacity ratio of the chilled water circuit is 2/3, and the ratio of the cold/hot water circuit is 1/3.

Similarly, the heat exchanger l4 of the embodiment shown in FIG. 5 is a modification of the embodiment shown in FIG. In the embodiment shown in FIG. 3, a tube 56 configured as a cold/hot water tube is connected between the headers 28a and 28b as a cold water tube. Therefore, in the embodiment shown in FIG. 5, the ratio of the cold water circuit is 3/4, and the ratio of the hot and cold water circuit is 1/4.

In the heat exchanger l4 shown in FIG. 6, a cold water circuit and a cold/hot water circuit are arranged in series with the flow path of the conditioned air.

That is, cold and hot water tubes with the number of passes of "4" were arranged on the upstream side of the air, and tubes with the same number of passes were arranged on the downstream side. In this case, the heat exchange efficiency during summer cooling will be somewhat lower than that of the heat exchanger shown in Figure 2 or Figure 3, but the ratio of the capacity of both the chilled water circuit and the cold/hot water circuit will be the same. It is 50%.

[Brief explanation of drawings]

FIG. IA and FIG. IB are circuit diagrams showing an air conditioner according to an embodiment of the present invention, with FIG. IA showing an example of winter operation, and FIG. IB showing an example of summer operation. FIGS. 2 to 6 are illustrative views showing different embodiments of the heat exchanger of the present invention. FIG. 7 is a circuit diagram showing an example of a conventional four-pipe air conditioner. In the figure, 10 is an air conditioner, 12A, 12B, .
... is an air conditioner, l4 is a heat exchanger, 24 is a cold water pipe,
26 is cold and hot water piping, 28a and 28b are headers for cold water (first and second), and 30a and 30b are headers for cold and hot water (third
and 4th) header, 32, 54.56 is tube, 3
4 is a cold heat source, 36 is a cold water pump, 38 is a hot heat source, 40 is a cold/hot water pump, 42, 44.46A, 46B, 48A,
48B, 50.52 indicates a control valve. Figure 1A large

Claims (1)

[Scope of Claims] 1. A first tube including first and second headers and a first tube connected between the first and second headers and having a first predetermined number of stages and a first predetermined number of rows. a cold water circuit, and a second tube connected between third and fourth headers and having a second predetermined number of stages and a second predetermined number of rows; or Heat exchanger with hot water circuit. 2. An air conditioner including a heat exchanger having both a cold water circuit and a cold water or hot water circuit, a cold heat source, cold water piping that supplies cold water from the cold heat source to the cold water circuit of the heat exchanger, a hot heat source, Cold and hot water piping that supplies cold water or hot water from the cold and hot sources to the cold water or hot water circuit of the heat exchanger, and cold and hot water piping that supplies cold water from the cold and hot water sources or from the hot heat source to the cold and hot water piping. An air conditioner equipped with a switching means for switching whether to supply hot water or not.