JPS63189794A - Heat exchanger - Google Patents

Abstract

PURPOSE:To make the wall thickness of a heat transfer pipe thin and improve the heat transfer coefficient in the pipe by providing a fin with holes like a net which has a section to make the air penetrate among concave grooves and headers respectively with a plurality of branch pipes which are inserted into and fixed to the inner circumferences at both ends of a flow channel with a groove. CONSTITUTION:A fin 2 with holes like a net consists of a in section 6 through which air can penetrate and concave groove 7 with a small diameter shaped like an arc, and the concave groove 7 has a thin-walled member in the flat plate shape formed in an arc in a small diameter circle with the inner diameter of about 4 mm. with its flat plane section at both ends 7a and 7b and its central section 7c with a groove. An inlet header 4 and outlet header 5 have their branch pipes 3 inserted into a heat transfer pipe 1 and those branch pipes are fixed on to the pipe 1 with an adhesive, etc. Air flows in the direction of F among the fins 2 with holes like a net and a heating medium flows in the flow channel 8 with groove of a heat transfer pipe 1. And, the heat exchange is carried out between the heating medium and air flow through the heat transfer pipe 1 and the fins 2 with holes like a net. In this heat exchange, because the heat transfer pipe 1 has the thin wall and the flow channel 8 of the small diameter with groove, the heat transfer coefficient in the pipe can be much raised, and on the other hand, on the side of the air, the fin 2 with holes like a with high heat conductivity is provided which is capable of increasing the capability of the heat exchanger because the surface area on the fins can be increased.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application The present invention relates to a finned heat exchanger used in room air conditioners and the like.

BACKGROUND OF THE INVENTION In recent years, the performance of finned heat exchangers has improved dramatically, and finned heat exchangers that combine thin heat exchanger tubes and mesh fins have been proposed.

The conventional heat exchanger as described above will be explained below with reference to the drawings.

FIG. 5 shows a perspective view of a conventional heat exchanger. In FIG. 5, reference numeral 11 denotes heat transfer tubes having an outer diameter d of 4 mm or less and arranged in parallel at a tube pitch P of 10 to 20 mm.

Reference numeral 12 denotes a mesh fi/, which is shaped like a panel through which air can flow, like a wire mesh. The mesh fin 12 has a sixth
As shown in the figure, a concave groove 13 for abutting the heat transfer tube 11 is formed, and two mesh fins 12 are formed as shown in FIG.
The heat exchanger B shown in FIG. 6 is constructed by positioning the heat transfer tubes 11 in the opposing grooves 13 and fixing them using brazing or adhesive.

The operation of the heat exchanger configured as above will be described below.

First, an air flow flows between the mesh fins 12 in the F direction,
A heat medium flows inside the heat exchanger tube 11 . And heat exchanger tube 1
1 and mesh fins 12, heat exchange takes place between the heating medium and the air stream. At that time, the mesh fins 12 are made of thin wire mesh, the heat transfer tubes 11 are made into thin tubes, and the tube pitch is set to 10 to 20 mm.
This makes it possible to improve the heat transfer coefficient while preventing a decrease in fin efficiency and an increase in ventilation resistance (for example, see Japanese Utility Model Application No. Sho F31-192185).

Problems to be Solved by the Invention However, in the above configuration, the heat transfer tube is made into a thin tube, so if an attempt is made to use a tube with internal grooves that can improve performance, the manufacturing cost of the heat transfer tube will increase significantly. ,
Since the fins are mesh-like, there is a problem in that the surface area of each fin cannot be increased.

In view of the above-mentioned problems, the present invention provides a high-performance heat exchanger that has a small diameter grooved flow path and can increase the fin surface area without using expensive heat exchanger tubes.

Means for Solving the Problems In order to solve the above problems, the heat exchanger of the present invention includes a thin flat plate with grooves in the center excluding both ends, and a concave groove formed in the shape of a small circular arc. a mesh fin having a plurality of fin portions arranged in parallel and allowing air to flow between the grooves;
A header having a small-diameter grooved flow path formed by making the grooves face each other and fixed, and a plurality of branch pipes that are inserted and fixed to the inner periphery of both ends of the narrow-diameter grooved flow path. It has a configuration that integrates both.

Effects of the present invention With the above-described configuration, the fins can form a grooved flow path with a small diameter, so that the groove thickness of the heat transfer tubes and the heat transfer coefficient within the tubes can be improved, thereby providing a low-cost, high-performance heat exchanger. can be obtained.

EXAMPLE Hereinafter, a heat exchanger according to an example of the present invention will be explained with reference to FIGS. 1 to 4.

FIG. 1 shows a perspective view of a heat exchanger in one embodiment of the present invention. FIGS. 2 to 4 show configuration diagrams of each component. A is a heat exchanger main body which is composed of a mesh fin 2 having a large number of heat transfer tubes 1 arranged in parallel, an inlet header 41 having a plurality of branch pipes 3, and an outlet header 6. As shown in FIG. 2, the mesh fin 2 is formed of a fin portion 6 like a wire mesh through which air can flow, and a concave groove 7 having a small diameter circular arc shape. The groove 7 has both ends 7a
, yb are flat portions, and the central portion 7C is a grooved thin plate-like member, which is formed into a small circular arc shape with an inner diameter of about 4ff. The heat exchanger tube 1 has four mesh fins 2 as shown in Fig. 3 and Fig. 4.
grooves 7A, 7A', 7B.

7B' are superimposed in the same direction, and the superimposed grooves 7A and 7A' and the grooves yB and yB' are brought into opposing contact with each other and pressed together using a jig C, and then heated with brazing or using an adhesive. It is constituted by a grooved channel 8 with a longitudinal diameter formed by fixing the grooves. For the inlet header 4 and outlet header 6, the branch pipes 3 are inserted into the heat transfer tubes 1 and fixed with adhesive or the like. The fin portions eA, eA', eB, and eB' of the mesh fins 2 are arranged uniformly at a pitch approximately equal to a rod of the outer diameter of the heat exchanger tube 1, leaving fixed portions at both ends of the grooves 7, 7'. is forming.

The operation of the heat exchanger configured as described above will be explained below. First, an air flow flows between the mesh fins 2 in the F direction, and a heat medium flows in the grooved flow passages 8 of the heat exchanger tubes 1. Then, heat exchange is performed between the heat medium and the air flow via the heat exchanger tubes 1 and the mesh fi/2. At this time, the heat transfer tube 1 has a thin-walled, small-diameter grooved flow path 8, which can greatly improve the heat transfer coefficient inside the tube.On the other hand, the air side has mesh-like fins 2 with a high heat transfer coefficient, and the surface area of the fins has been reduced. Since it can be made the same as the conventional method, the capacity of the heat exchanger can be greatly improved.

As described above, according to this embodiment, a plurality of concave grooves 7 are arranged in parallel, each of which is formed by forming a thin flat plate in the shape of a circular arc with a small diameter and having a groove 7C in the central portion excluding one both ends.

A plurality of mesh fins 2 made up of four or more pieces having fin portions 6 that allow air to flow between the grooves 7, and the grooves 7.
A small-diameter grooved flow path 8 formed by opposing and fixedly abutting a concave groove 7', and a plurality of grooved channels 8 inserted into and fixed to the inner periphery of the flat portions 7a and 7b at both ends of the grooved flow path 80. By integrally fixing a header having branch pipes, a heat exchanger with mesh fins having a thin-walled, inner-grooved, small-diameter heat exchanger tube can be constructed, thereby reducing the diameter and thinning of the heat exchanger tube 11. The mesh fin 2 has a high heat transfer coefficient while ensuring the surface area of the fin part 6 is the same as the conventional one.
Therefore, the capacity of the heat exchanger can be greatly improved.

Effects of the Invention As described above, the present invention has a thin flat plate with grooves in the center excluding both ends, and a plurality of concave grooves formed in a narrow arc shape are arranged in parallel, and a plurality of concave grooves are arranged in parallel between the concave grooves. A plurality of mesh-like fins arranged in parallel and having fin portions that allow air to flow between the grooves, and a groove with a small diameter formed by making the grooves opposing the grooves face each other and fixed to each other. By integrally fixing a grooved flow path and a header having a plurality of branch pipes that are inserted into and fixed to the inner periphery of both ends of the grooved flow path, a mesh-like structure having thin-walled, inner-grooved, small-diameter heat transfer tubes is formed. By constructing a heat exchanger with fins and making the heat exchanger tubes smaller in diameter and grooved on the inside, it is possible to make the heat exchanger tubes smaller in diameter and thinner, and improve the heat transfer coefficient inside the tubes. A finned heat exchanger can be obtained.

[Brief explanation of the drawing]

FIG. 1 is a perspective view of a heat exchanger in an embodiment of the present invention;
Figure 2 is a perspective view of the mesh fin in Figure 1 before assembly;
The figure is the A-A'vfr plane view of Fig. 1, and Fig. 4 is the B of Fig. 3.
Figure 5 is a perspective view of a conventional heat exchanger, Figure 6 is a perspective view of the mesh fin in Figure 6 before assembly, Figure 7 is B in Figure 6. -B/ is a sectional view. 1...Heat transfer tube, 2...Mesh fin,
3...Branch pipe, 4...Inlet header, 6
...Exit header, 7...Concave groove, 8.
...Grooved flow path. Name of agent: Patent attorney Toshio Nakao and 1 other person1-
--Irritating fever? ---Cross-cut fin 3-m-λ pipe 4-Inlet header 5-Outlet header Fig. 1 △ , =-11 100mm large fin Fig. 5

Claims (1)

[Claims] A plurality of meshes each having a plurality of concave grooves formed in a thin circular arc shape formed in a thin circular arc shape on a thin flat plate with grooves in the center excluding both ends and having fin portions that allow air to flow between the concave grooves. fins, a small diameter grooved flow path formed by opposing the grooves and the grooves facing each other and fixed to each other, and a plurality of branches inserted into and fixed to the inner periphery of both ends of the grooved flow path. A heat exchanger comprising: a header having a tube;