JPS63150565A - Heat exchanger - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application This invention relates to a heat exchanger used in, for example, an evaporator and a condenser provided in a refrigerator of a car air conditioner.

Conventional technology Conventionally, for example, a refrigerator for a car air conditioner consists of a liquid receiver containing high-pressure liquefied refrigerant, an expansion valve, an evaporator that performs the freezing action, a compressor that compresses the evaporated refrigerant gas, and a high-pressure refrigerant gas. Refrigerating machine oil was circulated through the cycle together with the refrigerant to lubricate, seal, and cool the mechanical friction parts of the compressor.

However, the presence of such oil along with the refrigerant
Inside the heat exchange tubes of the evaporator and condenser, oil adheres to the heat transfer walls or stays inside the heat exchange tubes, which impedes heat transfer and reduces the cooling performance of the evaporator or the heat dissipation performance of the condenser. As a result, the refrigerating capacity of the refrigerator decreases, and as oil accumulates in the heat exchange tubes of the evaporator and condenser, the absolute amount of water that returns to the compressor decreases, and the mechanical friction caused by oil decreases. There is a problem in that various functions such as lubrication, sealing, and cooling are not performed sufficiently, and in severe cases, seizure occurs in the friction parts, resulting in a decrease in the compression performance of the compressor.

Purpose of the Invention The purpose of the present invention is to solve the above-mentioned problems, and to separate the oil circulating together with the refrigerant in the refrigerator before introducing it into the heat exchange tubes of the evaporator and condenser, thereby allowing only the refrigerant to enter the heat exchange tubes. This makes it possible to maintain high thermal conductivity and greatly improve heat exchange efficiency. Furthermore, the separated oil can be remixed with the refrigerant after heat exchange and sent to the compressor. The functions of lubrication, sealing, and cooling of the mechanical friction parts in the refrigerator can be reliably performed with sufficient oil, thereby preventing seizure of the mechanical friction parts and, in turn, improving the refrigerating capacity and durability of the refrigerator. The purpose of the present invention is to provide a heat exchanger that can significantly improve performance.

SUMMARY OF THE INVENTION In order to achieve the above object, the present invention provides a heat exchange tube provided in a refrigerator in which oil is circulated together with a refrigerant and has a plurality of refrigerant passages, and both ends of the heat exchange tube. A heat exchanger having a refrigerant inlet header and a refrigerant discharge header attached to the refrigerant inlet header, and an oil separator installed at the end of the refrigerant inlet header or at the end of the refrigerant inlet pipe connected thereto. is provided, and the tip of the oil feed pipe connected to the bottom of the oil separator is connected to the end of the refrigerant discharge header or the end of the refrigerant discharge pipe connected thereto at the outlet portion of the header on the refrigerant discharge side. The main topic is heat exchangers.

Example Next, embodiments of the invention will be described based on the drawings.

In Figure 1, (1) is a refrigerator installed in a car air conditioner, and this is a liquid receiver (2) that contains high-pressure liquefied refrigerant.
, an expansion valve (3), an evaporator (4) that performs a refrigeration action, a compressor (5) that compresses evaporated refrigerant gas, and a condenser (6) that condenses high-pressure refrigerant gas. There is. A blower fan (7) is arranged on the - side of the evaporator (4), and a cooling fan (8) is arranged on the - side of the condenser (6).
) are arranged, and each evaporator (
4) and the refrigerant passages of the condenser (6).

The evaporator (4) is made of aluminum and is
As shown in the figure, a flat heat exchange tube (10) having a large number of refrigerant passages (11) and bent in a serpentine shape, and a heat exchange tube (
The refrigerant introduction side header (1
2) and a refrigerant discharge side header (13),
An oil separator (14) is provided at the wind pressure side end of the header (12) at the inlet of the refrigerant introduction side header (12), and an oil feed pipe (14) is connected to the bottom of the oil separator (14).
The tip of (5) is connected to the inflow side end of the refrigerant discharge header (13) at the outlet of the header (13).

The oil #I container (14) has a substantially cubic casing (16
) is provided with a deflector (18) that faces the refrigerant inlet (17) and is inclined upwardly away from the refrigerant inlet (17). - (18) lower end and refrigerant inlet (
17) The casing bottom wall (tea) between the side wall with
An oil discharge port (19) communicating with the oil feed pipe (15) is opened in the portion. Furthermore, corrugated fins (30) are interposed between the vertical straight pipe portions (10a) of the meandering flat heat exchange tubes (10).

The condenser (6) is also made of aluminum and has substantially the same construction as the evaporator (4), as shown in FIGS. 4 and 5. That is, four refrigerant passages (21)
It has a flat heat exchange tube (20) bent in a serpentine shape, and a refrigerant introduction side header (22) and a refrigerant discharge side header (23) attached to both ends of the heat exchange tube (20). An oil separator (24) is installed at the inlet end of the rudder (22) at the inlet of the refrigerant introduction header (22).
) is integrally provided, and the tip of the ura feed pipe (25) connected to the bottom of the oil separator (24) connects to the air inlet of the header (23) at the outlet of the refrigerant discharge side header (23). Connected to the side end.

The oil separator (24) includes a deflector disposed inside the refrigerant introduction header (22) in an inclined manner so as to face the refrigerant introduction port (27) and to move upward away from the refrigerant introduction port (27). - (28), and is equipped with a deflector - (28).
An oil discharge port (29) communicating with the oil feed pipe (25) is opened in the bottom wall (22a) of the header between the lower end of (28) and the side wall having the refrigerant inlet (27). Furthermore, corrugated fins (30) are interposed between the horizontal straight pipe portions (20a) of the meandering flat heat exchange tubes (20).

Next, the operation of the refrigerator (1) will be explained.

First, the high pressure liquefied refrigerant from the liquid receiver (2) passes through the expansion valve (3) and becomes low pressure. This refrigerant contains refrigeration oil, and the low-pressure mist of refrigerant and oil are transferred to the evaporator (4
), they hit the deflector (18), and the oils with higher specific gravity fall by themselves to the bottom of the casing (16) or fall down the inclined surface of the deflector (18). It flows down. This allows only low pressure refrigerant to flow from the inlet header (12) to the heat exchange tube (1
0) to exchange heat with the air. On the other hand, the ura separated by the deflector (18) flows out from the oil outlet (19) on the bottom wall (lea) of the casing (16), and is connected to the refrigerant discharge side header (
13), where it is mixed with the refrigerant gas vaporized in the heat exchanger (10). Therefore, no oil remains in the heat exchange tube (10) of the evaporator (4).A sufficient amount of oil is sent to the compressor (5) together with the refrigerant gas, so the The sliding, sealing, and cooling effects of mechanical friction parts are reliably performed by the oil, and seizure of mechanical friction parts does not occur at all.Furthermore, there is no oil in the heat exchange tube (10) of the evaporator (4). Since only the refrigerant is introduced, oil does not adhere to the heat transfer surface of the heat exchange tube (10), maintaining high thermal conductivity, and the evaporator (4) has extremely excellent cooling performance. It is something that exists.

The mixture of high pressure refrigerant gas and oil from the compressor (5) is then introduced into the oil separator (24) of the condenser (6) where, as in the evaporator (4) above, these mixtures are Upon hitting the deflector (28), the oil with a high specific gravity falls by itself to the bottom of the header (22) or flows down along the inclined surface of the deflector (28). As a result, only the high-pressure refrigerant is introduced into the heat exchange tube (20) of the condenser (6) to exchange heat with the air. On the other hand, the oil separated by the deflector (28) flows out from the oil outlet (29) on the bottom wall (22a) of the refrigerant introduction side header (22), and then flows from the oil feed pipe (25) to the refrigerant discharge side header ( 2
3), where it is fed into the benefactor end of the heat exchange tube (
20) is mixed with the liquefied refrigerant condensed in the refrigerant. Since only the refrigerant is introduced into the heat exchange tube (20), there is no risk of oil adhering to the heat transfer surface of the heat exchange tube (20) or remaining inside the heat exchange tube (20). The condenser (6) has excellent heat dissipation performance.

The high pressure liquefied refrigerant and oil are then sent to the receiver 'ri (2) and stored therein.

The oil separator (14) (24>) is joined together with heat exchanger manufacturing parts in a furnace when manufacturing the evaporator (4) and condenser (6), for example, by vacuum brazing. It is preferable that the oil feed pipes (15) (25) connected to the oil separators (14) (24) are placed on the benefactor side of the evaporator (4) and condenser (6), respectively. .

This is because even if refrigerant were to get mixed into the oil feed pipes (15) (25), it would be quickly heat exchanged with the air on the benefactor side and become steam, which would then be compressed from the tip of the oil feed pipes (15) (25). This is because the liquid is discharged toward the machine (5), so liquid return cannot occur.

In addition, in the above embodiment, the oil separator (14) (24
) is provided at the end of the refrigerant introduction side header (12) (22) of each heat exchanger of the evaporator (4) and condenser (6); It may be provided at the end of a series of refrigerant introduction pipes (the illustrated path). In addition, in the embodiment, the tip of the ura feed pipe (15) (25) connected to the bottom of the oil separator (14) (24) is connected to the refrigerant discharge side header (
13) Although it is connected to the end of (23), it may be connected to the end of a refrigerant discharge pipe (path shown) that continues to the header (13) (23).

Further, in the above embodiment, the case where the present invention is applied to a corrugated fin type evaporator (4) and condenser (6) is explained, but the present invention can be similarly applied to other types of heat exchangers. It is something to be admired.

Effects of the Invention As described above, the heat exchanger according to the present invention has a refrigerant introduction side header (12) (22) at the inlet portion thereof.
12) An oil separator (14) (24) is provided at the end of (22) or the end of the refrigerant introduction pipe connected thereto, and the ura feeder is connected to the bottom of this oil separator (14) (24). The tip of the pipe (15)<25) is connected to the refrigerant discharge side header (1
3) At the exit part of (23), the same header (13) (2
Since it is connected to the end of 3) or the end of the refrigerant discharge pipe connected to this, the ura that circulates together with the refrigerant in the refrigerator (1) is introduced into the heat exchange pipe (20) Heat exchange tubes (10) (20) that separate the refrigerant at the front
), thereby maintaining high thermal conductivity and greatly improving heat exchange efficiency. Moreover, the separated ura can be remixed with the refrigerant after heat exchange and sent to the compressor (5), so that a sufficient amount of lubrication, sealing and cooling of the mechanical friction parts in the compressor (5) can be carried out. This can be done reliably with oil, which can prevent seizing of mechanical friction parts, and can also prevent the freezing machine (1
) has the effect of significantly improving the refrigerating capacity and durability of

[Brief explanation of the drawing]

The drawings show an embodiment of the present invention, and FIG. 1 is a system diagram of a refrigerating machine cycle, FIG. 2 is an enlarged partially cutaway perspective view of an evaporator, and FIG. 3 is an oil separator portion of FIG. 2. Enlarged longitudinal cross-sectional view of
Figure 4 is a partially cutaway enlarged perspective view of the condenser, Figure 5 is the third
FIG. 3 is an enlarged vertical cross-sectional view of the oil separator portion shown in the figure. (1)... Refrigerator, (4)... Evaporator, (5)...
・Compressor, (6)...Condenser, (1G) (20)・
... Heat exchange tube, (11) (21) ... Refrigerant passage, (1
2) (22)... Refrigerant introduction side header, (13) (
23)... Refrigerant discharge side header, (14) (24)
...Oil separator, (15) (25)...Oil feed pipe.

Claims (1)

[Claims] A heat exchange tube (10) (20), which is provided in a refrigerator (1) in which oil is circulated together with a refrigerant and has a plurality of refrigerant passages (11) (21), and a heat exchange tube (10) ( 2
Refrigerant introduction side header (12) attached to both ends of
) (22) and a refrigerant discharge side header (13) (23), the refrigerant introduction side header (12)
At the entrance of (22), the same header (12) (22)
An oil separator (14) (24) is provided at the end of the refrigerant introduction pipe or the end of the refrigerant introduction pipe connected thereto, and the oil separator (14)
Oil feed pipe (15) connected to the bottom of (24) (25)
A heat exchanger whose tip end is connected to an end of the refrigerant discharge side header (13) (23) or an end of a refrigerant discharge pipe connected to the header (13) (23) at the outlet portion of the header (13) (23).