JPS63156995A - Heat exchanger - Google Patents

Abstract

PURPOSE:To keep a high thermal transfer rate and prevent a clogging caused by a frosting action by a method wherein non-symmetrical fins are alternatively arranged around a pipe and at the same time the cut and raised portions of slits arranged in the fins are arranged alternately. CONSTITUTION:Fins 1a and 1b having different length are placed it the right and left sides around a center of a pipe 2 of a heat exchanger. A gas flow advancing direction is indicated by an arrow F. Fins 1a and 1b are mounted alternately, and at the same time the fins 1a and 1b are provided with the cut and raised portions 7-10 of slits only in the same direction of the right and left sides of the pipe 2. With these arrangements, since there are some cut and raised portions 7-10 of the slit with respect to the gas flowing direction F, the heat transfer rate can be improved and maintained, and at the same time a fin pitch of the cut and raised portions 7-10 can be made the same as with the fin pitch (p), so that the occurence of clogging caused by the frosting can be reduced.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a heat exchanger, and particularly to a heat exchanger that has a high heat transfer coefficient and is suitable for preventing frost clogging.

[Conventional technology]

A conventional heat exchanger in which the fins are provided with cut-and-raised portions is disclosed in Japanese Patent Laid-Open No. 57-37696, and No. 3
As shown in the figure, 1 is a fin and 2 is a pipe. FIG. 4 is a sectional view of the heat exchanger at the pipe 2 portion of FIG. 3. Slits are cut into the surface of the fin 10 to provide raised cut and raised portions 3.4.5.6. Note that F indicates the direction of travel of the airflow. FIG. 5 is a sectional view taken along line B-B in FIG.
The fin 1 is provided with raised portions 3.4.5, 6. In this way, the heat exchanger provided with the cut and raised portions 3.4.5.6 formed by cutting slits into the fins 1 and raising them up has a short representative length in the airflow direction F, so the heat transfer coefficient is , becomes larger.

[Problem that the invention seeks to solve]

In the above conventional technology, because of the cut and raised parts, the gap between the fins is narrowed to about half of that without the cut and raised parts, so when frost forms on the fins 1, the wind stops flowing and the amount of heat transfer is reduced. The object of the present invention is to provide a heat exchanger that has a high heat transfer coefficient and is less likely to cause frost formation.

[Means for solving problems]

The above purpose is to arrange asymmetrical fins alternately around the pipe in a heat exchanger that combines fins and pipes, and to position the cut and raised portions of the slits provided in the fins at every other fin. This is achieved by

[Effect]

By placing fins with different lengths from the center of the pipe in the direction of airflow F, and creating slits and cut-outs in the extended areas of every other fin, the heat transfer coefficient on the fin surface can be increased. , performance can be improved. Also, every other fin has slits and cut-and-raised parts where the fin pitch doubles, so the fin pitch does not become narrower where the cut-and-raised parts are provided. (same as when no raised part is provided), even if frosting occurs, it is possible to prevent the occurrence of zero knots between the fins.

〔Example〕

An embodiment of the present invention will be described below with reference to FIGS. 1 and 2.

FIG. 1 is a sectional view of the main part of the heat exchanger, in which fins 1a and 1b of different lengths are placed on the left and right sides of the center of the pipe 2. F indicates the direction of air flow.

Figure 2 is a cross section taken along line A-A in Figure 1, with fins 1a and 1b.
are installed every other sheet, and 1a and 1b have slit cut-out portions 7,
8.9.10.

According to this embodiment, since the cut and raised portions 7.8.9.10 of the slit are provided in the direction of the airflow F, it is possible to maintain an improvement in the heat transfer coefficient, and the cut and raised portions 7.8.9, Since the fin pitch of IO can be made equal to the fin pitch P without cut and raised edges, it is possible to reduce the number of 0 knots due to frost formation.

(Effects of the Invention) According to the present invention, while maintaining the performance of the heat exchanger with a high heat transfer coefficient, the fin gap can be doubled compared to the conventional one even when used under conditions that cause frost formation. This has the effect of preventing zero binding and making the heat exchanger capable of long-term operation.

[Brief explanation of the drawing]

FIG. 1 is a front view of the main parts of the heat exchanger of the present invention, and FIG.
AA sectional view in the figure, Figure 3 is an external view of a conventional heat exchanger,
FIG. 4 is a front view of essential parts of a conventional heat exchanger, and FIG. 5 is a sectional view taken along line BB in FIG. 3. 1...Fin, 2...Pipe, 3.4.5.6.7
．． 8.9.10... Cut and raised portion, F... Airflow direction, P... Fin pitch. g i de; : 1 1... fin g+w Figure S + b 1 phi〉 P finhi 1 arrow

Claims (1)

[Claims] In a heat exchanger that combines fins and pipes, asymmetrical fins are arranged alternately around the pipe, and
A heat exchanger characterized in that cut and raised portions of the slits provided in the fins are located at every other fin.