JPS6153637B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a heat exchanger in which fins are formed on the outer surface of a refrigerant passage by cutting.

In recent years, heat exchangers in which fins are formed by cutting on one or both opposing surfaces of the outer surface of a refrigerant passage have been developed and are being applied to automobile air conditioners and the like. This type of heat exchanger usually has a structure as shown in FIG. The fin width in the direction of wind speed (in the direction of the arrow in Figure 1) is short and the temperature boundary layer cannot develop sufficiently, all of which contribute effectively to improving heat transfer performance. There is.

However, if you try to apply this heat exchanger to devices that are used with frost on the heat exchanger, such as refrigerators and heat pump air conditioners, the fins on the air inlet side will quickly become clogged with frost because the fin pitch P is small. This makes it unsuitable for actual use. If the fin pitch is made large enough to withstand frost formation, the entire heat exchanger becomes large, which not only significantly increases the cost, but also makes it impossible to install it in the limited storage space. Furthermore, it has disadvantages such as the difficulty of installing a suitable defrosting means, so it has not yet been used as an exchanger where frost may accumulate.

An object of the present invention is to eliminate the drawbacks of the prior art described above and to provide a heat exchanger suitable for use in a refrigerator equipped with a freezer compartment and a refrigerator compartment.

In order to achieve the above object, the present invention provides fins with high fin height and large fin pitch on one side of the refrigerant passage, and provides fins with low fin height and small fin pitch on the other side, A high-temperature, high-humidity air flow path and a low-temperature, low-humidity air flow path are separated by a refrigerant path. High fins with large fin pitch are arranged to create a flow path for low-temperature, low-humidity air.
That is, fins with low fin height and small fin pitch are arranged in the air flow path of the freezer compartment to prevent frost clogging of the heat exchanger.

The present invention will be explained below with reference to embodiments shown in FIGS. 2 to 5. FIG. 2 is a perspective view showing a heat exchanger used in the present invention, in which 1 is a refrigerant passage, and inside is formed a refrigerant passage 3 shown in FIG. 3, which is a sectional view taken along the line - has been done. Reference numeral 4 indicates a fin having a low height and is formed on one outer wall of the refrigerant passage 1 by cutting. Reference numeral 5 denotes a tall fin, which is formed on the other outer wall of the refrigerant passage 1 by cutting. These fins 4 and 5 have a short fin width in the direction of wind speed (in the direction of the arrow) and have an appropriate gap 6 in which a defrosting heater can be inserted. A defrosting heater 7 is installed in the gap 6 of the heat exchanger, densely on the high fin 5 side and sparsely on the low fin 4 side.

8 is a refrigerant inlet pipe, and 9 is a refrigerant outlet pipe.

4 and 5 are cross-sectional views showing an embodiment of the present invention, and FIG. 5 is a longitudinal cross-sectional view of a refrigerator.
Reference numeral 15 denotes an inlet portion for high-temperature and humid air, ie, refrigerator room air, and 16 denotes an inlet portion for low-temperature, low-humidity air, ie, freezer room air. 18 is a refrigerator main body, 19 is a freezer compartment door, and 20 is a refrigerator compartment door. A partition 21 divides the inside of the refrigerator into a freezing compartment 22 and a refrigerating compartment 23, and a heat exchanger and a blower 25 are built inside to generate cooling air.

The refrigerant passage 1 separates the flow passages for refrigerator room air and freezer room air.

In the refrigerator configured in this way, the refrigerator compartment 2
3, the hot and humid return air enters the high fin 5 side of the heat exchanger from the air inlet section 15 and is cooled, and then is discharged to the refrigerator compartment 23 and circulated. On the other hand, the low-temperature, low-humidity return air from the freezer compartment 22 is returned to the air inlet section 1.
6 to the low fin 4 side of the heat exchanger and cooled, it is discharged to the freezer compartment 22 and circulated. Therefore, the heat exchanger does not become clogged with frost due to return air from the refrigerator compartment, unlike in the conventional case.

As described in detail above, according to the present invention, one side of the fins formed by cutting on the outer surface of the refrigerant passage is made higher than the other side, and relatively hot and humid air is Since the height of the fins is high and the fin pitch is large, relatively low temperature and low humidity air is allowed to flow into the side where the fin height is low and the fin pitch is small, frost clogging is less likely to occur and the overall size of the heat exchanger is increased. Therefore, there is no increase in cost or increase in the number of storage rooms.

[Brief explanation of the drawing]

FIG. 1 is a perspective view showing a conventional heat exchanger, FIG. 2 is a perspective view showing a heat exchanger used in the present invention, FIG. FIG. 5 is a sectional view showing an embodiment of the present invention, and FIG. 5 is a longitudinal sectional view of a refrigerator. 1... Refrigerant passage, 4... Low height fin, 5
...Tall fins, 7...Defrost heater, 1
5...High temperature and high humidity air inlet section, 16...Low temperature and low humidity air inlet section.

Claims (1)

[Claims] 1. A refrigerant passage formed in a substantially plate shape with a refrigerant passage formed therein, and a first and a second facing outer surface of this refrigerant passage, which are integrally formed with the refrigerant passage by cutting. In a heat exchanger having a plurality of fins formed on the first outer surface, the height of the first group of fins formed on the second outer surface is equal to that of the second group of fins formed on the second outer surface. is formed higher than the height, and its fin pitch is formed larger than the fin pitch of the second group of fins,
This heat exchanger is disposed inside the partition of the refrigerator, and the partition is separated into a flow path for air in the refrigerator compartment and a flow path for air in the freezer compartment by the refrigerant passage. A heat exchanger characterized in that the fins are arranged in an air flow path of a refrigerator compartment, and the second group of fins are arranged in an air flow path of a freezer compartment.