JPH0547764U - Radiator - Google Patents

Abstract

(57) [Summary] [Object] An object of the present invention is to reduce the ventilation resistance to the outside air without impairing the heat dissipation effect of the radiator. [Structure] The fins 2 located between a plurality of tubes 1 arranged in parallel in the horizontal direction have a coarse fin pitch on the ground side with respect to the top side.

Description

[Detailed description of the device]

[0001]

[Industrial applications]

 The present invention relates to an oil cooler cycle for cooling oil in a refrigeration cycle or a hydraulic system used in an air conditioner for an automobile, and particularly to improvement of a radiator used in this cycle.

[0002]

[Prior Art]

 In a conventional radiator of this type, as shown in Japanese Examined Patent Publication No. 3-45300, the refrigerant passage groups arranged in parallel are divided into a plurality of group rows, and one header has a plurality of refrigerant passage groups. The refrigerant is caused to flow to exchange heat with the outside air.

The refrigerant passage group is divided into three in the vertical direction, and the refrigerant is liquefied and the volume is reduced from top to bottom. This is because the high-pressure and high-temperature gaseous refrigerant radiates heat to the outside air and undergoes a phase change. In such a conventional radiator, heat radiation fins are arranged between the refrigerant passages in order to efficiently perform heat exchange.

[0004]

[Problems to be solved by the device]

 In the conventional fin arrangement, the fin pitch was the same at any position in the vertical direction of the heat exchanger (radiator). By the way, since there is no need to radiate the heat already in the ground side refrigerant passage where the refrigerant has been sufficiently cooled and liquefied, the fins provided in this part have almost no effect of promoting heat dissipation and become ventilation resistance of the outside air. There was a problem that it was wasted. In particular, in the case of a type in which this radiator is installed in front of a radiator that allows water for engine cooling of automobiles, we want to send as much outside air as possible to the radiator in the rear, but with the configuration described above , The outside air flowing to the radiator was reduced by the amount of ventilation resistance due to the fins on the ground side of the radiator, impairing the heat radiation effect of the radiator. This is not limited to the radiator of the refrigeration cycle, and the radiator of the oil cooler that cools the hydraulic oil has the same problem.

An object of the present invention is to reduce the ventilation resistance to the outside air as much as possible without impairing the heat dissipation effect of the radiator installed on the front surface of the radiator.

[0006]

[Means for Solving the Problems]

 The above object is achieved by making the fin pitch of the radiator rougher on the ground side than on the top side of the radiator.

[0007]

[Action]

 Refrigerant cooled by the radiator dissipates less heat in the refrigerant flowing in the ground side than in the refrigerant passage in the ceiling side, so the heat dissipation effect should be impaired even if the fin pitch for promoting heat dissipation becomes rough. There is no. On the other hand, the airflow resistance of the outside air is reduced by the amount of roughening the pitch of the fins, and the total amount of outside air flowing to the radiator arranged behind is increased, so that the heat dissipation effect (cooling effect) of the radiator is increased.

[0008]

【Example】

 As shown in FIG. 1, a radiator used in a refrigeration cycle of an air conditioner for a vehicle according to the present invention is arranged between a plurality of tubes 1 which are refrigerant passages arranged in parallel in a horizontal direction. It has a pair of headers 3 and 4.

The tube 1 and the fins 2 are made of aluminum, have substantially the same width, and are joined by brazing. The headers 3 and 4 are also made of aluminum and have a pipe shape. Both ends of the tube 1 are inserted into the headers 3 and 4, respectively, and joined by brazing. Further, caps 5 for closing are attached to both ends of the headers 3 and 4, respectively, while the right side An inlet pipe 6 is connected above the header 4, and an outlet pipe 7 is connected below the left header 3. In addition, 8 and 9 are side plates arranged on the outermost fin 2. By the way, each of the headers 3 and 4 on both sides is provided with one partition 9, which partitions the inside of each header 3 and 4 in the lengthwise direction, and is divided into upper and lower two chambers.

By installing the partition 9 as described above, all the refrigerant passages 10 (see FIG. 2) formed by the tube 1 group are provided with an inlet side passage group A and an outlet side each including a plurality of tubes 1. It is divided into three passage groups, a passage group C and an intermediate passage group B located in the middle of the passage groups, and the refrigerant is sequentially passed in a meandering manner around each passage group. Further, the intermediate passage group B includes a larger number of tubes than the outlet side passage group C, that is, the number of cooling medium passages, and the passage cross sectional area thereof is larger than that of the outlet side passage group C. The passage sectional area of the side passage group A is set to be larger than the passage sectional area of the intermediate passage group B.

On the other hand, the fins 2 are divided into three types according to the difference in fin pitch. The inlet side passage group A portion has fins 11 having the finest fin pitch, the outlet side passage group C portion has fins having the coarsest fin pitch, and the intermediate passage group B portion has fin pitches of fin 11. The fins 12 in the middle of the fins 13 are set so that the pitch of the fins is made coarser on the ground side than on the top side.

In the above structure, the refrigerant flowing from the refrigerant inlet pipe 6 in the upper portion of the right header 4 reaches the left header 3 through each tube 1 of the inlet side passage group A and then is inverted as shown in FIG. Flow through each passage of the intermediate passage group B to the right header 4, and further reverse to flow through each passage of the outlet side passage group C to the left header 3 and flow out of the radiator from the outlet pipe 7. Then, while flowing through each passage group, heat exchange is performed with the outside air flowing through the air flowing gap including the fins 2 formed between the tubes 1. The refrigerant passing through the inlet-side passage group A is still in a large gasification state, but since the passage cross-sectional area of the inlet-side passage group A is set large, the refrigerant-side heat transfer area is considered to be large. In addition, since the fins 11 having the finest fin pitch are installed, the heat transfer area on the air side is also large, and the condensation and heat exchange of the refrigerant are efficiently performed.

On the other hand, a part of the refrigerant passing through the intermediate passage group B is liquefied in the inlet side passage group A, so that it has a gas-liquid mixed state. Therefore, although the heat transfer area may be small, the passage cross-sectional area of the intermediate passage group B is set smaller than that of the inlet side passage group A, and the fin pitch is coarser than the fins 11. Since it is installed, it is possible to secure a refrigerant passage amount and an air-side heat transfer area for performing necessary and sufficient condensation and heat exchange. When passing through the outlet side passage group C, most of the refrigerant is already in a liquefied state and has a small volume, so the passage cross sectional area may be small. Accordingly, the outlet side passage group C has a small passage cross sectional area. Since it is set to be smaller than the intermediate passage group B, no space is wasted in passing the refrigerant. Also, the fin pitch is set to the coarsest fin 13, and it is only necessary to secure the minimum necessary air-side heat transfer area.

As described above, the fins 11 having the closest fin pitch are set in the inlet-side passage group A having a large refrigerant-side heat transfer area, and the air-side heat transfer area is also the largest. Therefore, efficient heat exchange is performed. Further, since the fins 12 and 13 having fin pitches corresponding to the amount of heat radiation are set in the intermediate passage group B and the outlet side passage group C, the ventilation resistance of the outside air flowing therethrough can be reduced without lowering the efficiency of heat radiation. It can be made smaller. That is, a large amount of outside air can be sent to the radiator, which is the same radiator installed behind the radiator, as much as the ventilation resistance is reduced. Therefore, the heat radiation effect (cooling effect) of the radiator is increased, which is particularly effective for a vehicle having severe heat resistance (for example, a turbo-charged engine vehicle).

In the above-described embodiment, the fin pitch is divided into three stages, but it may be divided into two or more stages.

[0016]

[Effect of the device]

 According to the present invention, since the fin pitch is made rough at the location where the refrigerant is sufficiently cooled and liquefied, that is, the refrigerant passage portion on the ground side where heat radiation is not necessary, the ventilation resistance of the outside air is reduced, The airflow can be increased and sent to the radiator located behind the radiator by the amount of reduced ventilation resistance without impairing the heat radiation effect of the radiator.

[Brief description of drawings]

FIG. 1 is an overall front view showing an embodiment of the present invention.

FIG. 2 is a circuit diagram showing a flow direction of a refrigerant.

FIG. 3 is a schematic diagram showing the pitch of fins.

[Explanation of symbols]

1 ... Tube, 2 ... Fin, 3, 4 ... Header, 11,
12, 13 ... Fins.

Claims (1)

[Scope of utility model registration request] 1. A pair of headers arranged in parallel on the left and right at a distance from each other, and a plurality of heat exchange tubes arranged horizontally and in parallel so that both ends communicate with the headers. A radiator provided with fins arranged in an air circulation gap between the tubes adjacent to the tubes, wherein the fin pitch is made coarser on the ground side than on the top side.