JPS632790Y2 - - Google Patents

Description

[Detailed Description of the Invention] Industrial Application Field The present invention relates to a finch tube heat exchanger used in air conditioners, freezers, refrigerators, and the like.

Conventional structure and its problems A typical finch-tube heat exchanger consists of a large number of flat plate-shaped fins arranged in parallel, and refrigerant pipes that pass through these fins. In recent years, grooved pipes have been adopted for refrigerant pipes on the refrigerant side to improve heat exchange efficiency.
On the air side, the fins are treated with slit-like cuts and louver-like cuts. Each of these exhibits its effects individually, and for example, by forming the above-mentioned cut and raised portions on the fins, it is expected that the heat transfer coefficient and performance will be improved. However, many treatments on the surface of the fins obstruct the flow of ventilation air, and although the heat transfer coefficient and performance can be improved as described above when the airflow exceeds a certain level, the ventilation resistance increases and the airflow rate decreases. In other words, it is necessary to increase the capacity of the blower.
In the end, total energy (power consumption) loss is unavoidable. Moreover, it had the disadvantage that it was not possible to improve performance at low wind speeds.

For example, the first method for surface processing the fins is
As shown in FIGS. 1 to 3, a fin 1 having a large number of cut and raised pieces 2 and 2' on the surface thereof, which are spread out at a predetermined angle from side to side, is known. Reference numeral 3 shown in the figure is a hole through which a refrigerant pipe (not shown) is perpendicular to the fin 1. The cut and raised pieces 2, 2' are the fins 1
On the other hand, because they are cut up and spread out alternately,
Fin 1 is divided in places and due to the boundary layer leading edge effect,
In addition, due to the turbulent flow promotion effect caused by the cut and raised pieces 2 and 2' disturbing the flow of ventilation air,
Improved heat transfer coefficient can be measured. In other words, it was possible to measure ability improvement. However, the cut and raised pieces 2 and 2' of the fin 1 are widened in such a way as to block the flow of ventilation air, and the projected area in the flow direction of ventilation air becomes large, resulting in ventilation resistance as described above. The problem was that there was an extreme increase in the number of

Purpose of the invention The present invention aims to improve the heat transfer coefficient of the fins of a finch-tube heat exchanger, that is, to improve the capacity, and to suppress the accompanying increase in ventilation resistance as much as possible. The purpose is to measure the improvement of exchange performance.

Structure of the Device To achieve this objective, the device bends the cut and raised pieces spread out on the left and right sides of a plate-like fin so that the end surface of the surface facing the ventilation air is perpendicular to the surface of the plate-like fin. Alternatively, by curving, the heat transfer coefficient is improved due to the boundary layer leading edge effect and the turbulence promotion effect, that is, the capacity is improved, and the ventilation resistance is improved by preventing all surfaces facing the airflow from colliding directly with the airflow. This is to keep the increase in the amount to a small value.

DESCRIPTION OF EMBODIMENTS An embodiment of the present invention will be described below with reference to the accompanying drawings.

In FIGS. 4 to 6, reference numeral 10 denotes plate-shaped fins, and a large number of these fins 10 are arranged in parallel, and refrigerant pipes (not shown) are passed orthogonally through these fins to form a heat exchanger. Reference numeral 11 denotes a large number of holes through which refrigerant pipes pass, and are arranged in a grid pattern with respect to the fins 10. Reference numerals 12 and 12' designate cut-and-raised pieces that are alternately cut and raised left and right between the fin edges facing the airflow (indicated by arrow A in the figure) and adjacent holes 11, and spread out at a predetermined angle. This cut and raised piece 1
2 forms a first opposing surface 13 that faces the direction of the ventilation air flow and collides with the air flow. The cut and raised piece 12 is bent diagonally by 90 degrees at approximately the center thereof, forming a first bent side 14 and a second opposing surface 15 that has a smaller amount of collision with airflow than the first opposing surface 13. do. Furthermore, the front portion of this second opposing surface 15 is bent from the lower end of the first bending piece 14 to form a second bending side 1.
6 and the fin surface of the plate fin 10 form a non-opposing surface 17 that is perpendicular to the surface of the plate fin 10 and does not collide with the airflow A.

In the above configuration, since the fins 10 are divided by the cut and raised pieces 12 that cut and raise the fins 10, a boundary layer leading edge effect can be obtained. Further, since the cut and raised pieces 12 protrude into the flow of ventilation air, the flow of ventilation air is disturbed, and a turbulence promoting effect can be obtained. In addition, the tip of the cut and raised piece 12, that is, the non-opposed surface 17, is bent at right angles to the fin surface, so it is parallel to the direction of the ventilation air flow and blocks the ventilation air flow. Since it is designed so that it does not become a bulge, ventilation resistance can also be kept relatively small. Therefore, due to the boundary layer leading edge effect and the turbulence promotion effect, it is possible to improve the heat transfer coefficient, that is, improve the capacity, and also to suppress the increase in ventilation resistance to a small value. .

In the above embodiment, the cut and raised piece 12 is bent in two steps such as the first bent side 14 and the second bent side 16 to form the surface 17 that does not face the airflow, but the invention is not limited to this. A similar effect can be obtained by twisting and curving the tip to form a surface that does not face the airflow at the tip.

Effects of the invention As is clear from the above explanation, the present invention has a plate-like fin with a large number of cut and raised pieces spread out from side to side, and which is continuous with the surface of the cut and raised pieces facing the direction of the ventilation air flow. Since the tip of the surface is bent so that it is perpendicular to the plate fin surface, the increase in ventilation resistance is kept to a minimum, while
This improves the heat transfer coefficient and improves capacity, resulting in an overall improvement in performance.

[Brief explanation of the drawing]

Fig. 1 is a front view of the fins of a conventional plate tube heat exchanger, Fig. 2 is a side view of the fins, Fig. 3 is a plan view of the fins, and Fig. 4 is a heat exchanger according to an embodiment of the present invention. FIG. 5 is a plan view of the fin, and FIG. 6 is a partially enlarged perspective view of the cut-and-raised piece. 10...fin, 12...cut and raised piece, 17...
...Non-opposed surface (tip surface).

Claims (1)

[Scope of utility model registration request] Consisting of a large number of plate fins arranged in parallel and a refrigerant pipe passing through the fins, a cut and raised piece is formed on the plate fin that extends left and right with respect to the air flow direction, and a surface of the cut and raised piece facing the air flow is formed on the plate fin. A heat exchanger in which the distal end of the continuous surface is bent or curved in stages so that it is approximately perpendicular to the surface of the plate fins.