JP2010196931A - Method of manufacturing heat exchanger - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a method of manufacturing a heat exchanger reducing manufacturing cost and the weight of the manufactured heat exchanger. <P>SOLUTION: The method is used for manufacturing the heat exchanger which includes aluminum header tanks 2, 3 each having brazing material layers formed on a pair of outer faces, and a plurality of aluminum heat exchange tubes 4 each arranged between both header tanks 2, 3, having both ends inserted into pipe insertion holes formed in the header tanks 2, 3 and brazed to the header tanks 2, 3. During brazing of the heat exchange pipes 4 to the header tanks 2, 3, an aluminum plate 26 with thickness 0.7-1.3 times thicker than the thickness of the peripheral walls of the header tanks 2, 3 is arranged in the vicinity of the heat exchange pipes 4 between both header tanks 2, 3. Due to this arrangement, a temperature difference between the header tanks 2, 3 and the heat exchange pipes 4 is maintained within 5°C until the temperature of the heat exchange pipes 4 reaches a brazing maximum temperature since it has reached 570°C. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a method for manufacturing a heat exchanger, and more particularly to a method for manufacturing a heat exchanger used as a condenser, an evaporator, a heater core, an automobile oil cooler, an automobile radiator, or the like of a car air conditioner.

  In this specification and claims, the term “aluminum” includes aluminum alloys in addition to pure aluminum. However, the notation using the element symbol “Al” naturally represents an element.

  In addition, in this specification and claims, the term “header tank” includes a necessary part of a plurality of members in addition to a finished product formed by brazing the necessary parts of a plurality of members. Including unfinished products from the previous stage. Further, in this specification and claims, the term “heat exchange tube” includes, in addition to those made of extruded shapes, bend a base plate into a flat hollow shape and braze a necessary part. In particular, in the latter case, an unfinished product in a previous stage for brazing a necessary portion is also included.

  As a heat exchanger for automobiles, a pair of aluminum header tanks spaced apart from each other and a distance between the header tanks in the length direction of the header tank, and both end portions of the header tank A plurality of aluminum flat heat exchange tubes inserted into the formed tube insertion holes and brazed to the header tank, and aluminum made between the adjacent heat exchange tubes and brazed to the heat exchange tubes The header tank comprises a cylindrical tank body having a brazing material layer on both inner and outer peripheral surfaces, and a closing member that is brazed to both ends of the tank body and closes the opening at both ends. Is widely used.

By the way, in recent years, heat exchangers for automobiles are required to have higher performance, lighter weight, etc., so that the wall of the heat exchange pipe will be made thinner or used as a material for forming the header tank. As a heat exchange pipe excellent in heat exchange efficiency that is used in the above-described automotive heat exchanger, the present applicant has first described a pair of flat walls facing each other, Two side walls provided across both side edges of the flat wall, and the first side wall is formed by combining a plurality of side wall forming portions integrally formed on the side edges of the two flat walls. 2 side walls are formed integrally with the two flat walls, the first side wall is formed at the side edge of the first flat wall and protrudes toward the second flat wall side, and the tip is at the height of the first side wall. Formed on the first side wall forming part located in the middle part and the side edge part of the second flat wall A second side wall forming portion that protrudes toward the first flat wall and has a tip positioned at an intermediate portion of the height of the first side wall and abutted against the tip of the first side wall forming portion; The first side wall forming portion is formed on the outer side portion of the heat exchange pipe in the width direction and protrudes to the second flat wall side, and the tip end is engaged with the side edge portion of the outer surface of the second flat wall. The tip portions of the first and second side wall forming portions, the outer surfaces of the first and second side wall forming portions and the third side wall forming portion, and the third side wall forming portion and the side edge portion of the second flat wall are brazed. And proposed a heat exchange pipe having an extremely shallow concave groove-like seam formed of a brazing portion and extending in the length direction between the second flat wall and the tip of the third side wall forming portion. (See Patent Document 1).

  The heat exchange tube described in Patent Literature 1 is entirely made of a single metal plate, and includes two flat wall forming portions, a connecting portion that integrally connects both flat wall forming portions and forms a second side wall, First and second side wall forming portions provided so as to protrude from the flat wall forming portion on the side edge opposite to the connecting portion in both flat wall forming portions, and a connecting portion in the first flat wall forming portion, The plate for manufacturing a heat exchange tube, which is provided with an extension for the third side wall forming portion provided by extending the opposite side edge, is bent into a hairpin shape on both sides of the connecting portion, and the first and The third side wall forming part is formed by abutting the end portions of the second side wall forming part, bending the third side wall forming part extension part so as to cover the outer surfaces of the first and second side wall forming parts, 3 At the side edge of the outer surface of the second flat wall forming part, the tip of the side wall forming part And making a heat exchange pipe made of a bent body, and the first side wall forming part and the second side wall forming part, the first and second side wall forming parts and the third side wall forming part, and the third side wall of the heat exchange pipe It is manufactured by simultaneously brazing the forming part and the second flat wall forming part. The heat exchange pipe of patent document 1 is the 1st side wall formation part and 2nd side wall formation part in the heat exchange pipe which consists of a bending body mentioned above at the same time as brazing of other parts at the time of manufacture of a heat exchanger, the 1st and The second side wall forming part and the third side wall forming part, and the third side wall forming part and the second flat wall forming part are simultaneously brazed.

  By the way, since the heat capacity of the heat exchange pipe made of the bent body is smaller than the heat capacity of the header tank, the heating rate of the heat exchange pipe made of the bent body is increased during the heating at the time of manufacturing the heat exchanger. The temperature of the heat exchange pipe is higher, for example, about 10 ° C., when the temperature rises faster than the temperature increase rate of the tank body and the header tank temperature reaches 570 ° C., the temperature at which the brazing filler metal melts. As a result, when the brazing filler metal melts from the outer peripheral surface of the tank body of the header tank, the molten brazing filler metal flows to the heat exchange pipe side where the temperature is higher, and the third side wall forming portion of the heat exchange pipe is formed by capillary action. The width direction of the heat exchange tube flows along the joint between the tip portion and the outer surface of the second flat wall forming portion and is formed by a minute groove formed along the contact portion between the heat exchange tube and the corrugated fin. Flowing into. As a result, the brazing material used for brazing the header tank and the heat exchange pipe is insufficient. Therefore, in order to perform the brazing between the header tank and the heat exchange pipe satisfactorily, it is necessary to increase the amount of brazing material covering the outer surface of the tank body, which increases the material cost and, in turn, the manufacture of the heat exchanger. There is a problem that the cost increases and the weight of the heat exchanger increases.

  Moreover, even when a heat exchange tube made of an aluminum extruded shape is used, a fine groove called a die line may be formed on the outer peripheral surface of the heat exchange tube during extrusion processing. There is a problem similar to the case of the heat exchange tube of Patent Document 1 described above.

JP 2004-17861 A

  An object of the present invention is to provide a method of manufacturing a heat exchanger that can solve the above-described problems, reduce manufacturing costs, and reduce the weight of the manufactured heat exchanger.

  In order to achieve the above object, the present invention comprises the following aspects.

1) A pair of aluminum header tanks that are spaced apart from each other, and a pipe insertion that is spaced between the header tanks in the length direction of the header tank and that both ends are formed in the header tank A heat exchanger comprising a plurality of aluminum heat exchange tubes inserted into the holes and brazed to the header tank, and a header tank having a brazing material layer on an outer surface of at least a portion where the tube insertion holes are formed; Heat exchange including heat exchange pipe and brazing the heat exchange pipe to the header tank by heating both ends of the heat exchange pipe into the pipe insertion hole of the header tank and then heating to a predetermined temperature In the manufacturing method of the vessel,
At the time of brazing the heat exchange pipe to the header tank, the temperature difference between the header tank and the heat exchange pipe from when the temperature of the heat exchange pipe reaches 570 ° C. to the maximum brazing temperature is kept within 5 ° C. The manufacturing method of the heat exchanger characterized by the above-mentioned.

  In the manufacturing method of 1) above, the temperature difference between the header tank and the heat exchange tube from the time when the temperature of the heat exchange tube reaches 570 ° C to the maximum brazing temperature is limited to 5 ° C or less. This is because if the temperature is within 5 ° C., it is possible to prevent the molten brazing material melted from the outer peripheral surface of the header tank from flowing to the heat exchange pipe side.

  In the manufacturing method of 1) above, the temperature of the header tank and the heat exchange pipe from the time when the temperature of the heat exchange pipe reaches 570 ° C. until the maximum temperature of brazing is reached, the higher the temperature of the header tank is. preferable.

  2) When brazing the heat exchange pipe to the header tank, in the vicinity of the heat exchange pipe between the header tanks, an aluminum plate having a plate thickness that is 0.7 to 1.3 times the wall thickness of the peripheral wall of the header tank To maintain the temperature difference between the header tank and the heat exchange tube within 5 ° C. from the time when the temperature of the heat exchange tube reaches 570 ° C. until the maximum temperature of brazing is reached. Exchanger manufacturing method.

  In the manufacturing method of 2), the thickness of the aluminum plate disposed in the vicinity of the heat exchange pipe between the header tanks is 0.7 to 1.3 times the wall thickness of the peripheral wall of the header tank. If the temperature is less than 7 times, the temperature of the heat exchange pipe from the time when the temperature of the heat exchange pipe reaches 570 ° C to the maximum temperature of brazing becomes higher than the temperature of the header tank by more than 5 ° C, If it exceeds 1.3 times, the heat capacity of the aluminum plate becomes too large, and the heating capacity of the brazing furnace becomes excessively high, which may be uneconomical.

  3) A stainless steel plate having a thickness of 0.2 to 1.0 times the wall thickness of the peripheral wall of the header tank in the vicinity of the heat exchange pipe between the header tanks when the heat exchange pipe is brazed to the header tank To maintain the temperature difference between the header tank and the heat exchange tube within 5 ° C. from the time when the temperature of the heat exchange tube reaches 570 ° C. until the maximum temperature of brazing is reached. Exchanger manufacturing method.

  In the manufacturing method of 3) above, the thickness of the stainless steel plate disposed in the vicinity of the heat exchange pipe between both header tanks is 0.2 to 1.0 times the wall thickness of the peripheral wall of the header tank. If the temperature is less than 2 times, the temperature of the heat exchange pipe from the time when the temperature of the heat exchange pipe reaches 570 ° C to the maximum temperature of brazing becomes higher than the temperature of the header tank by more than 5 ° C, If it exceeds 1.0 times, the heat capacity of the stainless steel plate becomes too large, and the heating capacity of the brazing furnace becomes excessively necessary, which may be uneconomical.

  4) A mounting tray having a plurality of receiving members is prepared, and a combination of a header tank and a heat exchange tube is placed so that the heat exchange tube contacts the receiving member and the header tank does not contact the receiving member. Including placing the header tank and the heat exchange pipe in this state and brazing the header tank and the heat exchange pipe, and the heat capacity of all the receiving members of the placement tray in contact with the heat exchange pipe is 0.5% of the heat capacity of both header tanks. The above 1) description in which the temperature difference between the header tank and the heat exchange pipe from the time when the temperature of the heat exchange pipe reaches 570 ° C. to the maximum temperature of brazing is kept within 5 ° C. Method of manufacturing a heat exchanger.

  In the manufacturing method of 4) above, the heat capacity of all receiving members of the mounting tray in contact with the heat exchange pipes is 0.5 to 2 times the heat capacity of both header tanks. The temperature of the heat exchange tube from the time when the temperature of the heat exchange tube reaches 570 ° C. until the maximum temperature of brazing is reached is higher than the temperature of the header tank by 5 ° C. This is because the heat capacity of the receiving member becomes too large, and the heating capacity of the brazing furnace is excessively high, which may be uneconomical.

  5) At the time of brazing the heat exchange pipe to the header tank, the portion of the heat exchange pipe existing between the two header tanks is covered with a metal foil having a reflectance of 50 to 99%, so that the temperature of the heat exchange pipe is 570. The method for producing a heat exchanger as described in 1) above, wherein the temperature difference between the header tank and the heat exchange tube from the time when the temperature reaches the maximum brazing temperature to the maximum brazing temperature is maintained within 5 ° C.

  In the manufacturing method of 5) above, the reflectance of the metal foil covering the portion existing between the two header tanks in the heat exchange pipe is 50 to 99%. If the reflectance is less than 50%, the temperature of the heat exchange pipe is The temperature of the heat exchange tube from the time when it reaches 570 ° C to the maximum brazing temperature is higher than the temperature of the header tank by more than 5 ° C, and when it exceeds 99%, the manufacturing cost of the metal foil increases. This is because it may be uneconomical.

  6) The header tank is formed of a material having a brazing filler metal layer containing zinc on its outer surface, and the heat exchange pipe is formed of a material having a layer containing zinc on its outer surface, The heat exchanger manufactured by the method according to any one of the above, wherein the difference between the zinc diffusion depth on the outer surface of the header tank and the zinc diffusion depth on the outer surface of the heat exchange pipe is 20 μm or less .

  According to the heat exchanger manufacturing method of 1) above, when the heat exchange pipe is brazed to the header tank, the header tank from the time when the temperature of the heat exchange pipe reaches 570 ° C. until the maximum temperature of brazing is reached. Since the temperature difference with the heat exchange pipe is kept within 5 ° C., the temperature difference between the header tank and the heat exchange pipe becomes small when the header tank temperature reaches 570 ° C., which is the temperature at which the brazing filler metal melts. Therefore, the molten brazing filler metal melted out of the header tank flows to the heat exchange pipe side and is prevented from flowing in a large amount along the concave groove of the heat exchange pipe due to capillary action. Therefore, there is no shortage of brazing material used for brazing between the header tank and the heat exchange pipe, the amount of brazing material covering the outer surface of the header tank can be reduced, the cost can be reduced, and the manufactured heat can be reduced. The weight of the exchanger can be reduced.

  According to the manufacturing method of the heat exchanger of 2) to 5) above, the temperature difference between the header tank and the heat exchange tube from when the temperature of the heat exchange tube reaches 570 ° C. until the maximum brazing temperature is reached, It can be kept within 5 ° C. relatively easily.

It is a perspective view which shows the whole structure of the capacitor | condenser for car air conditioners manufactured by the method of Embodiment 1 of this invention. It is a perspective view which shows the whole structure of the state which mounted the combination body on the mounting tray in manufacturing the capacitor | condenser for car air conditioners by the method of Embodiment 1 of this invention. It is an AA line expanded sectional view of FIG. It is a graph which shows the temperature log | history of a header tank at the time of manufacturing the capacitor | condenser for car air conditioners of FIG. It is a perspective view which shows the whole structure of the state which mounted the combination body on the mounting tray in manufacturing the capacitor | condenser for car air conditioners by the method of Embodiment 2 of this invention. FIG. 6 is an enlarged sectional view taken along line BB in FIG. 5. It is a perspective view which shows the whole structure of the state which mounted the combination body on the mounting tray in manufacturing the capacitor | condenser for car air conditioners by the method of Embodiment 3 of this invention. FIG. 8 is an enlarged cross-sectional view taken along line CC in FIG. 7.

  Embodiments of the present invention will be described below with reference to the drawings. In this embodiment, the method for manufacturing a heat exchanger according to the present invention is applied to the manufacture of a condenser for a car air conditioner using a chlorofluorocarbon refrigerant.

  In the following description, the same parts and the same parts are denoted by the same reference symbols throughout the drawings, and redundant descriptions are omitted. Furthermore, illustration of the brazing material is omitted in all drawings.

Embodiment 1
This embodiment is shown in FIGS.

  FIG. 1 shows the overall configuration of a capacitor for a car air conditioner manufactured by the method of Embodiment 1 of the present invention. FIG. 2 shows the overall configuration of a state in which the combined body is placed on the mounting tray in the manufacture of a car air conditioner capacitor, and FIG. 3 shows the configuration of the main part thereof. FIG. 4 is a graph showing the temperature history of the header tank and the heat exchange pipe when the car air conditioner capacitor of FIG. 1 is manufactured.

  In the description of the car air conditioner capacitor shown in FIG. 1, the top, bottom, left and right in FIG. 1 are referred to as top and bottom, and left and right. The downstream side in the ventilation direction (the direction indicated by the arrow X in FIG. It will be later.

  In FIG. 1, a capacitor (1) for a car air conditioner includes a pair of aluminum header tanks (2) (3) extending vertically and spaced apart in the left-right direction, and both header tanks (2) ( 3) A flat heat made of a plurality of aluminum extruded sections with the width direction facing the ventilation direction and spaced apart in the vertical direction, and both ends brazed to both header tanks (2) (3) Aluminum corrugated fin brazed to the heat exchange pipe (4) between the exchange pipe (4) and the adjacent heat exchange pipes (4) and outside the heat exchange pipes (4) at both upper and lower ends (5) and an aluminum side plate (6) disposed outside the corrugated fins (5) at both upper and lower ends and brazed to the corrugated fins (5).

  The left header tank (2) is divided into two upper and lower header parts (2a) and (2b) by a partition member (7) above the central part in the height direction, and the right header tank (3) is The upper and lower header parts (3a) and (3b) are partitioned by a partition member (7) below the central part. A fluid inlet (not shown) is formed in the upper header portion (2a) of the left header tank (2), and an aluminum bare material inlet member (8) having a fluid inflow passage (8a) leading to the fluid inlet is connected to the upper header portion ( It is brazed to 2a). In addition, a fluid outlet (not shown) is formed in the lower header portion (3b) of the right header tank (3), and an outlet member (9) made of aluminum bare material having a fluid outflow passage (9a) communicating with the fluid outlet is provided in the lower header. It is brazed to the part (3b).

  The left and right header tanks (2) and (3) are made of an aluminum pipe having a brazing filler metal layer on at least the outer surface, for example, a base plate made of an aluminum brazing sheet having a brazing filler metal layer on both sides is formed into a cylindrical shape and both side edges A tank body (11) having a plurality of pipe insertion holes (10) which are partially overlapped and brazed to each other and which are long in the front-rear direction, and brazed to both ends of the tank body (11) And an aluminum closing member (12) which is attached and closes both ends of the opening. The brazing material constituting the brazing material layer of the base plate that forms the tank body (11) of the header tank (2) (3) contains zinc, and although not shown, the header tank (2) (3) A zinc diffusion layer is formed on both the inside and outside of the tank body (11).

  The left and right ends of the heat exchange pipe (4) are inserted into the pipe insertion holes (10) formed in the tank body (11) of the left and right header tanks (2) and (3). It is brazed to the tank body (11) of (3). In a state before the heat exchange pipe (4) is brazed to the tank body (11), a zinc sprayed layer is formed in advance on the outer surface of the aluminum extruded profile constituting the heat exchange pipe (4). A zinc diffusion layer is formed on the outer surface of the heat exchange tube (4) brazed to the main body (11). Here, the difference between the diffusion depth of the zinc diffusion layer of the heat exchange pipe (4) and the diffusion depth of the zinc diffusion layer of the tank body (11) of the header tanks (2) and (3) is preferably 20 μm or less. .

  Hereinafter, a method for manufacturing the capacitor (1) will be described with reference to FIGS. In the description relating to FIG. 2 and FIG. 3, the top and bottom of FIG. 2 and FIG.

  First, the tank body (11) of the header tanks (2) and (3), the aluminum closing member (12), the aluminum-extruded heat exchange pipe (4), the aluminum corrugated fin (5), the aluminum side plate ( 6) An aluminum partition member (7), an aluminum bare material inlet member (8), and an aluminum bare material outlet member (9) are prepared. The tank main body (11) is formed by forming a base plate made of an aluminum brazing sheet having a brazing filler metal layer on both sides into a cylindrical shape and partially overlapping both side edges. A plurality of tube insertion holes (10) are formed in a portion of the tank body (11) opposite to the overlapping portion between the side edges of the base plate. The heat exchange pipe (4) has a minute groove extending in the length direction called a die line.

  Next, a pair of tank main bodies (11) having pipe insertion holes (10) are arranged at intervals, a closing member (12) is arranged at both ends of both tank main bodies (11), and a partition member (7 ) Is placed on the tank body (11). Further, the heat exchange tubes (4) and the fins (5) are alternately arranged, and both end portions of the heat exchange tubes (4) are inserted into the tube insertion holes (10) of the tank body (11). Further, a side plate (6) is disposed outside the corrugated fins (5) at both ends, and an inlet member (8) and an outlet member (9) are further disposed. Next, the tank body (11), closing member (12), heat exchange pipe (4), corrugated fin (5), side plate (6), inlet member (8) and outlet member (9) are temporarily fixed and combined. Create a body (15) and apply flux to the combination (15).

  Next, a mounting tray (20) is prepared, and the combined body (15) is placed on the mounting tray (20). The loading tray (20) is parallel to the rectangular frame (21), the columns (22) erected at the four corners of the frame (21), and the long sides of the frame (21). A support member (23) spanned on a pair of struts (22) located at both ends of the long side portion, and a plurality of strip plates attached detachably across the support members (23) Receiving bar (24) (receiving member). Each support member (23) has a plurality of receiving bar fitting notches (25) formed at intervals in the length direction. The receiving bar fitting notch (25) is inclined upward in one direction along the length of the support member (23). Both ends of the receiving bar (24) are detachably fitted in the receiving bar fitting notches (25) of both support members (23), and are inclined upward in one direction in the width direction. . Then, on the receiving bar (24), the combined body (15) is in line contact with the receiving bar (24) by the heat exchange pipe (4), and the tank body (11) of the header tank (2) (3) is The aluminum plate (26) is placed on the heat exchange pipe (4) of the combined body (15) so as not to contact the receiving bar (24). The plate thickness of the aluminum plate (26) is preferably 0.7 to 1.3 times the plate thickness of the base plate forming the tank body (11) of the header tanks (2) and (3). Also, the size of the aluminum plate (26) viewed from the plane can be placed between the header tanks (2) (3) of the combination (15), and all the heat exchange tubes (4) and corrugated fins It is preferable that the size covers (5). Here, the heat capacity of all the receiving bars (24) of the mounting tray (20) in contact with the heat exchange pipe (4) is less than 0.5 times the heat capacity of both header tanks.

  Thereafter, the mounting tray (20) on which the combined body (15) is placed is placed in a brazing furnace maintained at a predetermined temperature, for example, 600 ° C. to heat the combined body (15), and the closing member (12) and Brazing the partition member (7) to the tank body (11) to produce the header tank (2) (3), heat exchange pipe (4), header tank (2) (3), heat exchange pipe (4) And the corrugated fin (5), the corrugated fin (5) and the side plate (6), and the header tank (2) (3), the inlet member (8) and the outlet member (9) are brazed simultaneously. Thus, the capacitor (1) is manufactured.

  At the time of brazing, the aluminum plate (26) works to exchange heat with the header tank from the time when the temperature of the heat exchange tube (4) reaches 570 ° C until the maximum temperature of brazing is reached, as shown in FIG. The temperature difference from the tube (4) is kept within 5 ° C. As a result, when the temperature of the header tanks (2) and (3) reaches 570 ° C, which is the temperature at which the brazing filler metal melts, the temperature difference between the header tanks (2) and (3) and the heat exchange pipe (4) The brazing filler metal melted from the tank body (11) of the header tanks (2) and (3) flows to the heat exchange pipe (4) side, and the die line of the heat exchange pipe (4) due to capillary action It is prevented that a large amount flows along. Therefore, there is no shortage of brazing material used for brazing between the tank body (11) of the header tank (2) (3) and the heat exchange pipe (4), and the tank body of the header tank (2) (3). The amount of brazing material covering the outer surface of (11) can be reduced, the cost can be reduced, and the manufactured capacitor (1) can be reduced in weight.

  In the first embodiment, when the combination body (15) is placed on the mounting tray (20), the aluminum plate (26) is disposed only on the upper side of the combination body (15), but the aluminum plate is disposed only on the lower side. (26) may be arranged. Also in this case, the plate thickness of the aluminum plate is preferably 0.7 to 1.3 times the plate thickness of the base plate forming the tank body (11) of the header tanks (2) and (3). When the aluminum plate is disposed only on the lower side of the combination body (15), the aluminum plate is supported by the receiving bar (24) of the mounting tray (20), and the heat exchange tube (4) of the combination body (15). Is supported by the aluminum plate. Furthermore, when the combination body (15) is placed on the mounting tray (20), aluminum plates may be disposed on both upper and lower sides of the combination body (15). In this case, the total thickness of the two aluminum plates is 0.7 to 1.3 times the thickness of the base plate forming the tank body (11) of the header tanks (2) and (3). preferable.

  In the first embodiment, when the combination body (15) is placed on the mounting tray (20), the aluminum plate (26) is disposed on the upper side of the combination body (15). A stainless steel plate may be disposed on only one of the upper side and the lower side of the combination body (15). In this case, it is preferable that the plate thickness of the stainless steel plate is 0.2 to 1.0 times the plate thickness of the base plate forming the tank body (11) of the header tanks (2) and (3). Further, stainless steel plates may be arranged on both the upper and lower sides instead of arranging the stainless steel plates only on either the upper side or the lower side of the combination (15). In this case, it is preferable that the total plate thickness of both stainless steel plates is 0.2 to 1.0 times the plate thickness of the base plate forming the tank body (11) of the header tank.

Embodiment 2
This embodiment is shown in FIGS. 5 and 6, and is a method of manufacturing the car air conditioner capacitor shown in FIG. FIG. 5 shows the overall configuration of a state in which the combined body (15) is placed on the mounting tray (20) in the manufacture of a capacitor for a car air conditioner, and FIG. 6 shows the configuration of the main part.

  In the case of the second embodiment, the mounting tray (20) includes more receiving bars (24) than the mounting tray (20) of the first embodiment. The combined body (15) is placed directly on the mounting tray (20). Note that the aluminum plates (26) are not arranged on both the upper and lower sides of the combination (15). At this time, the heat exchange pipe (4) of the combined body (15) is received by the receiving bar (24). Here, the heat capacity of all the receiving bars (24) in contact with the heat exchange pipe (4) may be 0.5 to 2 times the heat capacity of both the header tanks (2) and (3) of the combined body (15). preferable.

  Then, the mounting tray (20) on which the combined body (15) is placed is placed in a brazing furnace maintained at a predetermined temperature, for example, 600 ° C., and the combined body (15) is heated, and the closing member (12) and Brazing the partition member (7) to the tank body (11) to produce the header tank (2) (3), heat exchange pipe (4), header tank (2) (3), heat exchange pipe (4) And the corrugated fin (5), the corrugated fin (5) and the side plate (6), and the header tank (2) (3), the inlet member (8) and the outlet member (9) are brazed simultaneously. Thus, the capacitor (1) is manufactured.

  At the time of brazing, the temperature of the heat exchange tube (4) is set to 570 as in the case of the first embodiment by the action of all the receiving bars (24) that come into contact with the heat exchange tube (4) of the mounting tray (20). The temperature difference between the header tank and the heat exchange pipe (4) from when the temperature reaches 0 ° C. until the maximum brazing temperature is reached is kept within 5 ° C. As a result, when the temperature of the header tanks (2) and (3) reaches 570 ° C, which is the temperature at which the brazing filler metal melts, the temperature difference between the header tanks (2) and (3) and the heat exchange pipe (4) The brazing filler metal melted from the tank body (11) of the header tanks (2) and (3) flows to the heat exchange pipe (4) side, and the die line of the heat exchange pipe (4) due to capillary action It is prevented that a large amount flows along. Therefore, there is no shortage of brazing material used for brazing between the tank body (11) of the header tank (2) (3) and the heat exchange pipe (4), and the tank body of the header tank (2) (3). The amount of brazing material covering the outer surface of (11) can be reduced, the cost can be reduced, and the manufactured capacitor (1) can be reduced in weight.

Embodiment 3
This embodiment is shown in FIGS. 7 and 8, and is a method of manufacturing the car air conditioner capacitor shown in FIG. FIG. 7 shows the overall configuration of a state in which the combined body (15) is placed on the mounting tray (20) in the manufacture of a car air conditioner capacitor, and FIG. 8 shows the configuration of the main part thereof.

  In the case of Embodiment 3, the total heat exchange pipe (4), all corrugated fins (5) and both side plates (6) of the combined body (15) are covered with aluminum foil (30), and in this state, the mounting tray (20) Place on top. The reflectance of the aluminum foil (30) is preferably 50 to 99%.

  Then, the mounting tray (20) on which the combined body (15) is placed is placed in a brazing furnace maintained at a predetermined temperature, for example, 600 ° C., and the combined body (15) is heated, and the closing member (12) and The partition member (7) is brazed to the tank body (11) to produce the header tank (2) (3), the heat exchange pipe (4), the header tank (2) (3), the heat exchange pipe (4) And the corrugated fin (5), the corrugated fin (5) and the side plate (6), and the header tank (2) (3), the inlet member (8) and the outlet member (9) are brazed simultaneously. Thus, the capacitor (1) is manufactured.

  At the time of brazing, due to the action of the aluminum foil (30), as in the case of Embodiment 1, the header tank from when the temperature of the heat exchange pipe (4) reaches 570 ° C. until reaching the maximum brazing temperature, The temperature difference with the heat exchange tube (4) is kept within 5 ° C. As a result, when the temperature of the header tanks (2) and (3) reaches 570 ° C, which is the temperature at which the brazing filler metal melts, the temperature difference between the header tanks (2) and (3) and the heat exchange pipe (4) The brazing filler metal melted from the tank body (11) of the header tanks (2) and (3) flows to the heat exchange pipe (4) side, and the die line of the heat exchange pipe (4) due to capillary action It is prevented that a large amount flows along. Therefore, there is no shortage of brazing material used for brazing between the tank body (11) of the header tank (2) (3) and the heat exchange pipe (4), and the tank body of the header tank (2) (3). The amount of brazing material covering the outer surface of (11) can be reduced, the cost can be reduced, and the manufactured capacitor (1) can be reduced in weight.

  Hereinafter, specific examples of the present invention will be described together with comparative examples.

Example 1
An aluminum brazing sheet having a thickness of 1.6 mm was used as a base plate for forming the tank body (11) of the header tanks (2) and (3). A brazing filler metal layer made of Al-8.7 wt% Si-1.2 wt% Zn was formed on both surfaces of the base plate. Further, a Zn sprayed layer was formed by spraying 8 g / m ² of Zn on the outer surface of the aluminum extruded profile forming the heat exchange tube (4). In addition to these tank body (11) and heat exchange pipe (4), closing member (12), corrugated fin (5), side plate (6), partition member (7), inlet member (8) and A combination body (15) was made using the outlet member (9). The size of the combined body (15), that is, the distance W between the outer surfaces of the header tanks (2) and (3) opposite to the heat exchange pipe (4) is 650 mm, and the header tanks (2) and (3) The length L was 450 mm (see FIG. 2).

  Next, as in the first embodiment, the combined body (15) is placed on the mounting tray (20), and an aluminum plate (26) having a thickness of 1.2 mm is placed on the upper side of the combined body (15). It was arranged so as to cover the total heat exchange pipe (4), all corrugated fins (5) and both side plates (6) of 15).

  Thereafter, the mounting tray (20) on which the combination (15) is placed is placed in a brazing furnace set at 600 ° C. to heat the combination (15), and the closing member (12) and the partition member (7) The header tank (2) (3) is manufactured by brazing the tank body (11), the heat exchange pipe (4), the header tank (2) (3), the heat exchange pipe (4) and the corrugated fin (5 ), Corrugated fin (5) and side plate (6), header tank (2) (3), inlet member (8) and outlet member (9) were respectively brazed at the same time to produce capacitor (1) .

Example 2
The capacitor (1) is the same as in Example 1 except that the thickness of the aluminum plate (26) disposed on the upper side of the combination (15) placed on the mounting tray (20) is 1.9 mm. ) Was manufactured.

Example 3
The same as in Example 1 above, except that a stainless steel plate having a thickness of 0.8 mm was placed instead of the aluminum plate (26) on the upper side of the combined body (15) placed on the mounting tray (20). A capacitor (1) was manufactured.

Example 4
Instead of placing the aluminum plate (26) on the upper side of the combined body (15) placed on the mounting tray (20), the total heat exchange tube (4 ), All the corrugated fins (5) and both side plates (6) were placed on the mounting tray (20) in a state of being covered with aluminum foil (30) having a reflectivity of 97%, except for the above embodiment The capacitor (1) was produced in the same manner as in 1.

Example 5
A capacitor was manufactured in the same manner as in Example 4 except that the reflectance of the aluminum foil was 50%.

Comparative Example A capacitor was manufactured in the same manner as in Example 1 except that the aluminum plate (26) was not disposed on the upper side of the combined body (15) placed on the mounting tray (20).

Evaluation test In Examples 1 to 5 and Comparative Example above, the temperature of the tank body (11) of the header tank (2) and (3) and the temperature of the heat exchange pipe (4) during brazing were measured using a thermocouple. When the temperature of the heat exchanger tube (4) reaches 570 ° C, the temperature of the tank body (11) of the header tank (2) (3) and the temperature of the heat exchanger tube (4) reach 600 ° C The temperature of the tank body (11) of the header tanks (2) and (3) was obtained. The results are shown in Table 1.

In addition, EPMA line analysis was performed for the diffusion depth of the Zn diffusion layer on the outer surface of the tank body (11) of the header tank (2) and (3) of the manufactured capacitor (1) and the outer surface of the heat exchange pipe (4). And measured. The results are also shown in Table 1.

  The ○ mark in the judgment column in Table 1 indicates the tank body of the header tank (2) (3) from when the temperature of the heat exchange pipe (4) reaches 570 ° C until it reaches the maximum brazing temperature of 600 ° C. It indicates that the temperature difference between (11) and the heat exchange tube (4) was kept within 5 ° C. Similarly, the X mark indicates that the temperature difference exceeded 5 ° C.

  The heat exchanger according to the present invention is suitably used for a refrigeration cycle constituting a car air conditioner.

(1): Capacitor (heat exchanger)
(2) (3): Header tank
(4): Heat exchange pipe
(10): Tube insertion hole
(20): Loading tray
(24): Receiving bar (receiving member)
(26): Aluminum plate
(30): Aluminum foil (metal foil)

Claims (6)

A pair of aluminum header tanks that are spaced apart from each other, and a pipe insertion hole that is spaced between the header tanks in the length direction of the header tank and both ends are formed in the header tank. A heat exchanger comprising a plurality of aluminum heat exchange tubes inserted and brazed to the header tank, and at least a header tank having a brazing material layer on the outer surface of the portion where the tube insertion hole is formed, and heat exchange Of the heat exchanger including brazing the heat exchange pipe to the header tank by preparing the pipe and inserting both ends of the heat exchange pipe into the pipe insertion hole of the header tank and then heating to a predetermined temperature. In the manufacturing method,
At the time of brazing the heat exchange pipe to the header tank, the temperature difference between the header tank and the heat exchange pipe from when the temperature of the heat exchange pipe reaches 570 ° C. to the maximum brazing temperature is kept within 5 ° C. The manufacturing method of the heat exchanger characterized by the above-mentioned. When brazing the heat exchange pipe to the header tank, an aluminum plate having a thickness that is 0.7 to 1.3 times the wall thickness of the peripheral wall of the header tank is disposed in the vicinity of the heat exchange pipe between the header tanks. 2. The heat exchanger according to claim 1, wherein the temperature difference between the header tank and the heat exchange pipe from the time when the temperature of the heat exchange pipe reaches 570 ° C. to the maximum brazing temperature is kept within 5 ° C. Manufacturing method. When brazing the heat exchange pipe to the header tank, a stainless steel plate having a thickness that is 0.2 to 1.0 times the wall thickness of the peripheral wall of the header tank is disposed in the vicinity of the heat exchange pipe between the header tanks. 2. The heat exchanger according to claim 1, wherein the temperature difference between the header tank and the heat exchange pipe from the time when the temperature of the heat exchange pipe reaches 570 ° C. to the maximum brazing temperature is kept within 5 ° C. Manufacturing method. A mounting tray having a plurality of receiving members is prepared, and a combination of a header tank and a heat exchange tube is combined so that the heat exchange tube contacts the receiving member and the header tank does not contact the receiving member. Including mounting the header tank and the heat exchange pipe in this state, and setting the heat capacity of all receiving members of the mounting tray in contact with the heat exchange pipe to 0.5 to 2 of the heat capacity of both header tanks. 2. The heat according to claim 1, wherein the temperature difference between the header tank and the heat exchange tube from the time when the temperature of the heat exchange tube reaches 570 ° C. to the maximum brazing temperature is maintained within 5 ° C. Exchanger manufacturing method. When brazing the heat exchange pipe to the header tank, the portion of the heat exchange pipe existing between the two header tanks is covered with a metal foil having a reflectance of 50 to 99%, so that the temperature of the heat exchange pipe becomes 570 ° C. The method for producing a heat exchanger according to claim 1, wherein a temperature difference between the header tank and the heat exchange pipe from the time of reaching the maximum brazing temperature to 5 ° C is maintained. The header tank is formed of a material having a brazing material layer containing zinc on the outer surface, and the heat exchange pipe is formed of a material having a layer containing zinc on the outer surface, A heat exchanger manufactured by the method according to any one of the above, wherein the difference between the zinc diffusion depth on the outer surface of the header tank and the zinc diffusion depth on the outer surface of the heat exchange tube is 20 μm or less.

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