JPH10141808A - Heat exchanger and its manufacture - Google Patents

Abstract

PROBLEM TO BE SOLVED: To improve efficiency of a heat exchanger and rationalize the cost by winding a metallic tube for flowing a heat medium closely around a cylindrical aluminum body, and welding both ends of the metallic tube to fixing metal fittings, and screwing the metal fittings to the aluminum body. SOLUTION: A copper tube 2 is wound closely around a cylindrical aluminum body 1 and conducts the heat of the aluminum body to a refrigerant. Copper metallic fittings 3 and 4 fix the ends on inlet side and the outlet side of the copper tube 2 and the aluminum body 1. The copper metal fittings 3 and 4 are screwed to the periphery of the aluminum body 1, and are brazed to the copper tube 2 so that the copper tube 2 may not loosen. The combustion gas generated by a burner 5 flows into the aluminum body 1, and the heat of combustion is conducted from a fin part 1a to the aluminum body 1. A refrigerant flows into the copper tube 2 from the high temperature side of the combustion gas, and flows to the downstream outlet of the combustion gas on low temperature side while absorbing heat. Hereby, the heat loss is small, and the heat efficiency is improved sharply.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a heat exchanger for transferring heat to a heat medium by exchanging heat of a combustion gas.

[0002]

2. Description of the Related Art In recent years, a refrigerant-heated air conditioner utilizing combustion heat of gas or oil has been put to practical use.

[0003] An example of a heat exchanger of the above-described refrigerant-heated air conditioner will be described below with reference to the drawings.

FIG. 4 shows a conventional heat exchanger for heating a refrigerant.
FIG. 5 is a sectional view of the same, and FIG. 6 is an enlarged sectional view of a copper tube fixing portion. 4 to 6, reference numeral 1 denotes an extruded aluminum body 1, which is provided with fins 1 a for absorbing heat from the combustion gas of the burner 5. A copper tube 2 for flowing a coolant is fixed to the copper tube supporting portion 1b from the inside at the outer peripheral portion of the aluminum main body 1, and the heat absorbed from the fin portion is transmitted to the coolant flowing in the copper tube. .

[0005]

However, in the heat exchanger constructed as described above, since the refrigerant alternately passes between the upstream side (high temperature) and the downstream side (low temperature) of the combustion gas, the heat loss is large and the efficiency is high. bad. Also, the number of parts of the copper tube 2 (straight tube part,
U-tube section). Further, in order to make the copper tubes 2 adhere to each other after the copper tube supporting portions 1b of the aluminum main body 1 are inserted, it is necessary to expand all the straight tube portions of each copper tube, and the number of manufacturing steps and brazing for connecting the copper tubes 2 to each other are required. Large manufacturing costs such as man-hours are required.

SUMMARY OF THE INVENTION The present invention has been made in view of the above problems, and provides a low cost and high heat efficiency combustion heat exchanger.

[0007]

SUMMARY OF THE INVENTION In order to solve the above-mentioned problems, the present invention provides a heat transfer medium on the outer periphery of a cylindrical aluminum body having fins for receiving heat from combustion gas therein and having both ends opened. The metal pipe to be flowed is tightly wound around the metal pipe, both ends of the metal pipe are welded to respective fixing brackets, and the fixing brackets are fixed to the aluminum body by screws. With the configuration of the heat exchanger, the efficiency of the heat exchanger can be improved and the cost can be rationalized.
Conventional problems can be solved.

[0008]

DETAILED DESCRIPTION OF THE INVENTION In order to solve the above-mentioned problems, the present invention provides a metal tube having a fin for receiving heat from a combustion gas therein and flowing a heat medium around an outer peripheral portion of a cylindrical aluminum body having both ends opened. Are tightly wound, and both ends of the metal tube are welded to respective fixing brackets, and the fixing brackets are fixed to the aluminum body by screws.

Further, according to the present invention, a fixing member 1 is screwed to an outer peripheral end portion of a cylindrical aluminum body having fins for receiving heat from a combustion gas and open at both ends. One end (entrance side) of the metal tube through which the heat medium flows is welded, the aluminum body is rotated to wind the metal tube in close contact with the outer periphery of the aluminum body, and wound to the other end (outlet side), and the outer periphery of the aluminum body The metal fitting 2 and the metal pipe are welded and fixed to the other end of the metal screw, and the outlet end of the metal pipe is cut to manufacture a heat exchanger.

[0010]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A heat exchanger according to an embodiment of the present invention will be described below with reference to the drawings. In the figure, the same components as those of the conventional example are denoted by the same reference numerals, and description thereof is omitted.

(Embodiment 1) In FIG. 1, (a) is a side view, (b) is a front view, and 1 has a fin for absorbing heat of a combustion gas on an inner surface, and is an extruded cylindrical shape. The aluminum body 2 is a copper tube which is wound tightly around the outer periphery of the aluminum body 1 and transfers the heat of the aluminum body to the refrigerant. The copper tubes 3 and 4 are used to fix the inlet and outlet ends of the copper tube to the aluminum body. Metal fittings. The copper fittings 3 and 4 are screwed to the outer peripheral portion of the aluminum body and fixed to the copper tube by brazing, so that the copper tube 2 is not loosened. Reference numeral 5 denotes a burner unit that generates combustion gas by combustion.

In the above configuration, the combustion gas generated by the burner 5 flows into the aluminum main body 1, and the combustion heat is transferred from the fin portion 1a to the aluminum main body 1. Refrigerant flows into the copper tube 2 from the high temperature side (right side in the front view) of the combustion gas and flows to the low temperature side combustion gas downstream side (left side) outlet while absorbing heat.

As is clear from the above embodiment, the heat exchanger of the present heat exchanger has a smaller heat loss and a lower heat efficiency than the heat exchanger shown in the conventional example because the refrigerant flows from the high temperature part to the low temperature part of the heat exchanger sequentially. Along with the dramatic improvement, the number of parts of the copper tube has been greatly reduced (one point is enough), and the number of processing steps for fixing the copper tube to the aluminum body can be greatly reduced. This has the effect.

The same effect can be obtained by using water, antifreeze, or the like as the heat medium flowing in the copper tube in addition to the refrigerant.

(Embodiment 2) FIG. 3 shows a method of manufacturing a heat exchanger according to the present invention. First, a copper extruded aluminum main body 1 having fins therein is provided with copper at an end of an outer peripheral portion thereof. The metal fitting 3 is screwed. Insert the copper tube 2 between the aluminum body 1 and the copper fitting, braze and fix one end of the copper tube. Then, while applying tension to the copper tube 2, place the aluminum body 1 around the cylindrical axis of the aluminum body 1. The copper tube is sequentially wound while being rotated and brought into close contact with the outer peripheral surface of the cylindrical portion. Then, at the time of winding to the other end, the copper fitting 4 is screwed to the aluminum body 1 so as to hold the copper pipe also at the multi-end, and then the copper fitting 4 and the copper pipe 2 are brazed to cut the copper pipe. . The heat exchanger shown in FIG. 1 is manufactured by the above method.

As is apparent from the above embodiment, in the method of manufacturing the present heat exchanger, one copper tube is directly wound around the aluminum body, so that the copper tube is expanded as in the heat exchanger shown in the conventional example. There is no need to adhere to the aluminum body or braze to connect the copper tubes, so that the number of manufacturing steps can be greatly reduced and the cost can be greatly reduced.

[0017]

As is apparent from the above embodiment, according to the first aspect of the present invention, a metal pipe for flowing a heat medium through an outer peripheral portion of a cylindrical aluminum body having fins for receiving heat from combustion gas therein. The heat medium flows sequentially from the high-temperature part to the low-temperature part by forming a heat exchanger in which both ends of the metal pipe are welded to the fixing bracket and the fixing bracket is fixed to the aluminum body with screws. Therefore, the thermal efficiency is greatly improved, the number of parts of the metal tube is significantly reduced (one point is sufficient), and it is possible to greatly reduce material costs.

Further, as in the second aspect of the present invention, a fixing bracket 1 is screwed to an outer peripheral end of a cylindrical aluminum body having fins for receiving heat from combustion gas, and heat is applied to the fixing bracket 1. One end (inlet side) of the metal tube through which the medium flows is welded, the aluminum body is rotated and the metal tube is wound around the outer circumference of the aluminum body while being in close contact with the outer circumference, and the other end (outlet side) is wound up. The metal fitting 2 is screwed to the other end, and the metal fitting 2 and the metal pipe are welded and fixed. Then, the metal pipe outlet end is cut and a heat exchanger is manufactured, so that the metal pipe is brought into close contact with the aluminum body. Processing man-hours and welding of metal pipes are not required, so that manufacturing man-hours can be significantly reduced and manufacturing costs can be greatly reduced.

[Brief description of the drawings]

FIG. 1 (a) is a heat exchanger outer side view showing a first embodiment of the present invention, and FIG. 1 (b) is a front view thereof.

FIG. 2 is a detailed sectional view of the copper pipe fixing portion.

FIG. 3 is a configuration diagram showing a method of winding a copper tube according to a second embodiment of the present invention.

FIG. 4 is a perspective view of a conventional heat exchanger.

FIG. 5 is a sectional view of the heat exchanger.

FIG. 6 is a detailed sectional view of the copper tube fixing portion.

[Explanation of symbols]

 1 Aluminum body 2 Copper tube 3, 4 Fixing bracket 6 Screw

Claims (2)

[Claims] 1. A metal tube for flowing a heat medium is wound tightly around the outer periphery of a cylindrical aluminum body having fins for receiving heat from combustion gas and open at both ends, and both ends of the metal tube are wound. A heat exchanger in which each fixture is welded to a fixture and the fixture is screwed to the aluminum body. 2. A first fixing bracket is screwed to an outer peripheral end of a cylindrical aluminum body having fins for receiving heat from combustion gas therein and having both ends opened, and a heat medium is supplied to the fixing bracket. One end of the flowing metal pipe is welded, the aluminum body is rotated, and the metal pipe is wound around the outer circumference of the aluminum body while being in close contact with the outer circumference of the aluminum body, and is wound up to the other end. A method for manufacturing a heat exchanger in which the second fixing fitting and the metal tube are fixed by welding, and then the outlet end of the metal tube is cut.